News

From Bread to Beer - Rescuing Leftover Bread From Landfill

  Would you be surprised to know that by opting for a beer made from excess bread, you could be protecting the planet just as you unwind with a refreshing beverage? This is the concept behind Alaric HUI, our alumnus of Master of Science in Environmental Management. His Bread-to-Beer project innovatively adopts the circular economy model to upcycle surplus bread by brewing them into beer. This waste management project saves these baked goods from ending up in landfills.   Upcycling the under-valued staple While pursuing his Master’s degree in Environmental Management at HKU, Alaric and his teammate Tiffany opted to conduct a research project, using it as an opportunity to apply their classroom-learnt theories to real life. After months of brainstorming, an idea finally clicked as he was reminded of this food waste problem from his days working at Cathay Pacific Catering Services (CPCS). As a waste-conscious person and a beer lover himself, Alaric was then inspired by a UK brewing company’s upcycling solution, which dawned on him to actualise the Bread-to-Beer idea in Hong Kong’s market.   From idea to implementation The duo invested hours into conducting background research. They even stood outside numerous small and chain bakeries at the end of the working day, and carried the to-be-discarded bread back home to be counted and made their own statistical estimates. Though, the biggest challenge was yet to come. They struggled to convince breweries to help produce a prototype batch without any tangible proof of their idea. Finally, they tried their luck by reaching out to their instructor of the home-brewing course they signed up together earlier.  Little did they know that the instructor was actually the founder of hEROES Beer Co., a locally renowned craft brewery. ‘Funny enough, without any hesitation, he just said yes. Fast forward to a month and a half later, the beer was successfully made, and he sent me 12 bottles of it,’ laughed Alaric at his lucky chance encounter.   Collaboratively produced by Cathay Pacific Catering Services and hEROES Beer Co., the VHHX beer was named as a tribute to the old Kai Tak airport, where VHHX stands for the International Civil Aviation Organization (ICAO) airport code.   Creating a more sustainable society Consolidating his idea into a practically-applicable proposal using insights gained from the MSc programme, he successfully persuaded his then employer CPCS to give the green light to implement his project. This gave birth to the VHHX Vienna Lager, completing his own circular journey of giving back to the place from where he got his inspiration. After thanking his supervisor Dr Janet CHAN of the School of Biological Sciences, Alaric wished to impart the essence of being altruistic to future students. ‘Think about how a project can benefit society, not only you. Because you will already benefit a lot from the process of doing the project itself,’ he emphasised. ‘I think the outcome of what you and your teammates have done can go beyond what you initially imagined,’ he reiterated as he looks forward to branching out into the industry on the back of this triumphant pilot project.       ‘I realised that there was a great impact created by human activities on our surroundings, especially problems like pollution and waste that are prevalent in Hong Kong. Learning this triggered me to want to do something focused on this area,   Alaric Shun Yuen HUI Co-founder of VHHX Vienna Lager 2018 - 2020 Master of Science in Environmental Management, The University of Hong Kong  

NEWS DETAIL

HKU-Harvard physicists predict the novel entangled states on programmable quantum simulators

Quantum science has not only deepened human understanding of the structure of matter and its microscopic interactions, but also introduced a new paradigm of computing and information science — quantum computing and quantum simulation. Quantum informatics research has won the 2022 Nobel Prize in Physics. Among many quantum computing and simulation platforms, Rydberg Atom Arrays is considered the most promising system to show quantum superiority among many programmable quantum simulator platforms in recent years due to its largest number of qubits and highest experimental accuracy. Such optical lattices consist of individual neutral alkaline-earth atoms with significant dipole moments trapped in arrays of microscopic dipole traps, that can be optically moved at will to make desired lattice geometry. Each atom can be excited to its Rydberg state, and a pair of excited states interact through their dipole moments via a long-range interaction (see Fig.2). Such Rydberg atom arrays are believed by many to be the system with the highest level of experimental precision and number of qubits in recent years within all platforms for programmable quantum simulators. The observations of quantum phase transitions and the signature of topological orders from Rydberg atom arrays have been reported with tremendous speed. Figure 2. Quantum innovations using Rydberg atoms. Photo courtesy: Caltech However, the long-range interaction and the Rydberg blockade mechanism in these optical lattices can have both pros and cons. On the one hand, they give rise to the high precision of experimental quantum control, as mentioned above. Still, on the other hand, they enforce the constraints on modelling the system. Such quantum-constrained many-body systems are among the hardest to study from theoretical and numerical perspectives. Without a precise theoretical understanding of the complete phase diagrams and novel quantum phases, future experiments will have no guidance to continue. Such an apparent conundrum, faced by all scientists in the field, is partially and substantially solved by a joint effort of Research Assistant Professor Zheng YAN and Associate Professor Zi Yang MENG from the Department of Physics, The University of Hong Kong (HKU) and the renowned physicist Professor Subir SACHDEV (member of American Academy of Arts and Sciences) from Harvard University and his then student Dr Rhine SAMAJDAR now Postdoctoral fellow at Princeton University and Dr Yan-Cheng WANG (Researcher) from Beihang Hangzhou Innovation Institute Yuhang at Hangzhou. Their research work has been published in the recent issue of the high-profile, multidisciplinary scientific journal Nature Communications. They designed a new triangular lattice quantum dimer model with soft constraints to be as close as possible to experiment conditions and developed the sweeping cluster algorithm for quantum Monte Carlo simulations that could solve such soft-constrained quantum many-body systems efficiently. Their simulations and theoretical analysis successfully map out the expected phase diagram of Rydberg arrays on the Kagome lattice (as shown in Fig.3). They found not only the expected and conventional nematic and stagger types of the solid phases but also the exotic highly entangled Z2 quantum spin liquids (QSL) with large parameter regimes in the phase diagram.   Figure3. The obtained phase diagram in this work. Within different phases, the even Z2 quantum spin liquid (QSL) and odd Z2 QSL are topological ordered novel states of matter that are expected to exist in the Rydberg atom array experiments on Kagome lattices. They identify these novel phases by designing non-local measurements of string operators and other physical observables in the quantum Monte Carlo simulations. As shown in Fig.4, the difference between QSL and trivial paramagnetic phase is distinguished successfully. The most exciting thing is that a path connecting odd Z2 QSL, trivial paramagnetic (PM) phase, and even QSL and solid phases has been revealed, which is very useful in guiding the Rydberg arrays experiment. In addition, they have also studied the dynamics and interactions of the fractional quasiparticles (visons) in the Z2 QSL to give more experimentally probable evidence. Figure 4. Distinguishing the topological orders and trivial phases by designed measurements. Illustration: Phase transitions between QSLs and the PM phase. Data along the QSL–PM–QSL path, indicated by the dashed line at V = 0.9 in Fig. 2. (a) The energy density is smooth with increasing µ. (b) The polarization Mx reveals the first-order phase transition between the PM phase and the two Z2 QSLs. (c) The dimer filling changes continuously in the PM phase, and the filling also exhibits a first-order phase transition between the PM phase and QSLs. (d) The string operator is zero in the trivial PM phase but positive (negative) in the even (odd) Z2 QSL. Illustration: Phase transitions between QSLs and the PM phase. Data along the QSL–PM–QSL path, indicated by the dashed line at V = 0.9 in Fig. 2. (a) The energy density is smooth with increasing µ. (b) The polarization Mx reveals the first-order phase transition between the PM phase and the two Z2 QSLs. (c) The dimer filling changes continuously in the PM phase, and the filling also exhibits a first-order phase transition between the PM phase and QSLs. (d) The string operator is zero in the trivial PM phase but positive (negative) in the even (odd) Z2 QSL.   These results highlight the richness of their constrained models derived for Rydberg array systems and exploit various new phases induced by the long-range interactions and Rydberg blockade mechanism. Their work will become the guiding information for future developments in the field. More details can be found in the journal paper.  The work was supported by the Research Grants Council of HKSAR, the Areas of Excellence “2D Materials Research: Fundamentals Towards Emerging Technologies”, the Seed Funding Quantum-Inspired explainable-AI at the HKU-TCL Joint Research Centre for Artificial Intelligence. We thank the HPC2021 system under the Information Technology Services at the University of Hong Kong and the Tianhe-II platform at the National Supercomputer Center in Guangzhou for their technical support and a generous allocation of CPU time.

NEWS DETAIL

HKU Stephen Hui Geological Museum Curating an Exhibition on Poland’s Distinctive Landforms In Celebration of the International Geodiversity Day

In celebrating the UNESCO International Geodiversity Day (October 6, 2022), the Stephen Hui Geological Museum at The University of Hong Kong (HKU) is showcasing a special exhibition entitled “On the Geology Trail” from that day for two months (till December 6, 2022), presenting a series of beautiful photos of Poland’s geological landforms. The exhibition is a collaboration between the HKU Stephen Hui Geological Museum and the Consulate General of the Republic of Poland in Hong Kong. An opening ceremony took place at the museum yesterday with the attendance of the Consul General of the Republic of Poland in Hong Kong Dr Aleksander DAŃDA, HKU Dean of Science (Interim) Professor Vivian Wing-Wah YAM, Head of HKU Department of Earth Sciences Dr Man Hoi LEE and other consuls from various countries. Postglacial Landscape - The valley of Five Polish lakes is one of the most beautiful valleys in the whole Tatras. Thirteen thousand years ago, along with the warming of the climate and disappearance of the glaciers, the forms created as a result of both erosion and accumulative activity of the glacier, were exposed here. Glacial niches widened and deepened under the influence of erosive activity of the glacier, and after the glacier retreated they transformed into cirque lakes. Photo credit: Łukasz Chełmiński Geodiversity is broadly defined as a variety of geological environments, natural landscapes and landforms that are formed and shaped by rocks, minerals, fossils, sediments and soils with natural processes. Connecting human activities, landscapes and cultures, geodiversity is an integration of human communities and nature, and it plays essential roles because human well-being is based on the diversity of geological resources. Scientific knowledge about how geological and geomorphological processes occur in nature contributes to understanding past climate changes, and this knowledge can be applied to understand how climate may change in the future, and is very important for natural disaster prevention. Initiated by Poland, Portugal and the United Kingdom, UNESCO established the International Day of Geodiversity, aiming to raise the awareness of societies about the importance of our planet's inanimate natural resources, as geodiversity is the foundation of communities and an intrinsic part of humanity’s relationship with nature. HKU Stephen Hui Geological Museum is showcasing a special exhibition entitled “On the Geology Trail”, presenting a series of beautiful photos of Poland’s geological landforms.   This joint special exhibition showcases a series of photos of Poland's unique geological landforms, in conjunction with the museum’s permanent collections “Hong Kong Geological History”, and other exhibits including minerals, rocks and fossils. This provides visitors with an excellent opportunity to appreciate the geological resources and geodiversity of Poland and Hong Kong. The aim of this event, as well as other events at the museum, is to disseminate scientific knowledge to the public and encourage the public to explore different local geological resources. “October 6 is an excellent opportunity to raise the awareness of Earth Sciences. Today we celebrate the International Geodiversity Day which was established in 2021 by UNESCO (on the initiative of Poland, Great Britain and Portugal). The aim of establishing the International Geodiversity Day was to raise public awareness of the importance of inanimate nature – and today, together with our friends from The University of Hong Kong, we are doing exactly that: bringing unique Poland’s geological landscapes to the attention of Hong Kong’s audiences,” said Dr Aleksander Dańda, Consul General of the Republic of Poland. “A greater scientific knowledge about the diversity of geological resources would provide us with a better understanding of climate change, which demands swift action. We are pleased to support the International Geodiversity Day by curating this exhibition to raise the public awareness of the importance of geodiversity and its linkage to all forms of life,” said Professor Vivian Wing-Wah Yam, Dean of Science (Interim) and Philip Wong Wilson Wong Professor in Chemistry and Energy. “We are excited to collaborate with the Consulate General of the Republic of Poland on this exhibition of the diverse geological landforms of Poland. It fits perfectly with the mission of the Stephen Hui Geological Museum to engage visitors of all ages on the nature and evolution of our planet and to inspire an appreciation of the dynamic natural world of Earth Sciences and its application to daily life,” said Dr Man Hoi Lee, Head of Department of Earth Sciences. Details of the Exhibition - On the Geology Trail Language: English and Polish Date: October 6 to December 6, 2022 Venue: 1/F display cabinet, Stephen Hui Geological Museum, The University of Hong Kong Opening Hours:  Mon – Fri, 1pm to 6pm (Closed on Saturdays and Sundays, University and Public Holidays) Entrance fee: Free Admission General Enquiry: shmuseum@hku.hk   Photo on the left: From the left - Dr Aleksander DAŃDA , Consul General of the Republic of Poland in Hong Kong; Dr Man Hoi LEE, Head of HKU Department;  Mrs Dorota DAŃDA of Financial, Cultural and Educational Affairs at Consulate General of Poland in Hong Kong; Professor Vivian Wing-Wah YAM, Dean of Science (Interim). Photo on the right: An opening ceremony took place at HKU Stephen Hui Geological Museum yesterday with the attendance of various consuls general in Hong Kong and other friends of the museum.  

NEWS DETAIL

HKU Initiates Global Ant Census, At Least Twenty Quadrillion Ants Dominate The Global Ecosystems

Ants are one of the most successful and dominant groups of organisms. Their high degree of social organisation enables them to colonise nearly all ecosystems and regions around the globe. Over millions of years of co-evolution, they have developed tight interactions with a plethora of organisms ranging from plants, to fungi, to other insects or even larger vertebrates. Some regard ants as foes, others as vital partners or as a food resource. Simply put, ants are everywhere. But how many are there? What is their total weight? What is their percentage relative to other organisms, including us, humans? What about the distribution of ant abundance around the globe? Is it homogenous, or does it fluctuate between different biomes or habitats, like some regions of the world host more species than others? Ultimately, can we thus observe areas where ant abundance is especially high, with potential implications for other organisms as well? While these questions may appear trivial at first, they have enormous implications for our understanding of natural processes since ants are such key players in most ecosystems and have numerous and complex interactions with other organisms. These questions have been addressed by a team from the Insect Biodiversity and Biogeography Laboratory of the School of Biological Sciences (SBS) at The University of Hong Kong (HKU) in a recent publication in the Proceedings of the National Academy of Sciences of the USA (PNAS). The researchers used a novel approach to attempt counting every ant on Earth. While ants may appear insignificant to many of us at first glance, this study shows that their combined number is, in fact, substantial and that further investigation and understanding of their abundance patterns may help in the preservation of ecosystems and species around the globe. Dr Patrick SCHULTHEISS, a lead author of the new study and then a Postdoctoral Fellow at SBS, explains: “For decades, ant researchers have been incredibly busy studying ant communities the world over. They have collected thousands of ant samples to identify the species and often counted all the ants as well when publishing their results in scientific articles. We were able to compile such data from nearly 500 different studies from all over the world and written in many different languages. In this way, we have been able to quantify the density of ants in various parts of the globe, and also to estimate the total number of ants on Earth.” Previous estimates, including one from famous biologists Bert Hölldobler and Ed Wilson, had ranged from 1015 to 1016 individuals. These were essentially educated guesses, as a global, representative dataset was unavailable at the time. In this new study, the total number of ants on Earth is estimated to be 2 to 20 times that number. “Our estimate of the global ant population is 20 x 1015 individuals,” says co-lead author Dr Sabine NOOTEN, former Postdoctoral Fellow at SBS. “That’s a 20 with 15 zeroes, which is difficult to appreciate. In terms of biomass, all the ants on Earth weigh more than all the wild birds and mammals combined, or about 20% of human biomass.” The study also found that ants are unevenly distributed over the global land surface. As a general pattern, tropical regions harbour more ants than non-tropical regions, but this also depends on the local ecosystem. “Ants are particularly abundant in forests, and surprisingly, in arid regions but become less common in human-made habitats, with potential consequences for the ecological services (e.g. decomposition, pest control) they may provide,” explains Dr Nooten. The study also highlights major gaps in our understanding of global patterns of biodiversity. Dr Benoit GUÉNARD, head of the Insect Biodiversity and Biogeography Laboratory of HKU SBS and senior author of the study adds: “As global efforts to synthetise hundreds of years of research on insect biodiversity come to fruition, we begin to realise how little we know and how scarce data are for numerous and vast regions of the world. This is very worrisome as the world is changing rapidly, and scientists are lacking baseline information on how biodiversity may be changing in these regions. Societies and governments need to be more proactive about this and make important efforts and investments to fill these gaps. Counting ants is not a difficult exercise, and citizens from all over the world, with the right methodology, could be involved in providing a more profound understanding of the changes that are happening over time and space.” The journal paper can be accessed here. 

NEWS DETAIL

HKU geologist proposes the number of ancient martian lakes might have been dramatically underestimated by scientists

Lakes are bodies of water fed by rainfall, snowmelt, rivers and groundwater, through which, Earth is teeming with life. Lakes also contain critical geologic records of past climates. Though Mars is a frozen desert today, scientists have shown that Mars contains evidence of ancient lakes that existed billions of years ago, which could contain evidence for ancient life and climate conditions on the red planet. Through a meta-analysis of years of satellite data that shows evidence for lakes on Mars, Dr Joseph MICHALSKI, a geologist in the Department of Earth Sciences, The University of Hong Kong (HKU) proposed that scientists might have dramatically underestimated the number of ancient Martian lakes that once existed. Michalski and the international team recently published their results in Nature Astronomy, which describe a global analysis of ancient Martian lakes. “We know of approximately 500 ancient lakes deposited on Mars, but nearly all the lakes we know about are larger than 100 km2,” explains Michalski. “But on Earth, 70% of the lakes are smaller than this size, occurring in cold environments where glaciers have retreated. These small-sized lakes are difficult to identify on Mars by satellite remote sensing, but many small lakes probably did exist. It is likely that at least 70% of Martian lakes have yet to be discovered.” Scientists monitor these small lakes on Earth in order to understand climate change. The missing small lakes on Mars might also contain critical information about past climates. The recent paper also reports that most known Martian lakes date to a period 3,500 to 4,000 million years ago, but each of the lakes might have lasted only a geologically short time (10,000 to 100,000 years) during this time span. This means that ancient Mars was probably mostly cold and dry as well, but it warmed episodically for short periods of time. Michalski adds, “Because of the lower gravity on Mars and the pervasive, fine-grained soil, lakes on Mars would have been very murky and might not have allowed light to penetrate very deeply, which could present a challenge to photosynthetic life, if it existed.” Pingualuit crater lake in Canada is a modern-day example of a cold impact crater-hosted lake on Earth analogous to ancient crater lakes on Mars.Credit: Google Earth Lakes contain water, nutrients and energy sources for possible microbial life, including light for photosynthesis. Therefore, lakes are the top targets for astrobiological exploration by Mars Rovers such as NASA’s Perseverance rover now on Mars. But Michalski warns, “Not all lakes are created equal. In other words, some Martian lakes would be more interesting for microbial life than others because some of the lakes were large, deep, long-lived and had a wide range of environments such as hydrothermal systems that could have been conducive to the formation of simple life.” From this point of view, it might make sense to target large, ancient, environmentally diverse lakes for future exploration. “Earth is host to many environments that can serve as analogs to other planets. From the harsh terrain of Svalbard to the depths of Mono Lake - we can determine how to design tools for detecting life elsewhere right here at home. Most of those tools are aimed at detecting the remains and residues of microbial life,” said Dr David BAKER, an ecologist at HKU School of Biological Sciences who is well-informed about the Earth’s microbial systems in lakes. China successfully landed its first lander, Zhurong, on Mars in May this year. Zhurong is currently roving the plains of Utopia Planitia, exploring mineralogical and chemical clues to recent climate change. China is also planning a sample return mission likely to occur at the end of this decade, which could target one of the interesting lake deposits. Dr Joseph Michalski is an Associate Professor in the Department of Earth Sciences and Deputy Director of the Laboratory for Space Research at HKU. He worked with colleagues from Canada, USA, and the UK on the research, which is funded by the Research Grants Council in Hong Kong.   Click here to learn more about his reasearch.  The journal paper can be accessed from here. 

NEWS DETAIL

Ecologists find evidence that pet and medicine trades Bring tokay geckos from across Asia into Hong Kong Impacting resident gecko populations and highlighting local and global conservation needs

Tokay geckos are one of the most charismatic reptile species in Asia and the second largest gecko species in the world. They also are one of the most heavily traded reptiles, with millions exported every year from Southeast Asia, mostly as dried goods in Traditional Chinese Medicine (TCM), but also live for the pet trade. In Hong Kong, tokay geckos can be found in the wild, where they benefit from a protected status since 2021*, but also in pet shops and TCM markets. However, little is known about the impacts of the trade on local tokay populations nor the extent to which the TCM market impacts tokay geckos across its distribution. New research from the Conservation Forensics Lab in the School of Biological Sciences at The University of Hong Kong (HKU) has been investigating the origins of tokay geckos in Hong Kong, both the wild ones and those sold in TCM shops. The findings were just published in the Proceedings of the Royal Society B: Biological Sciences. Dr Pauline DUFOUR, a then PhD student and now in a postdoctoral position at HKU, led the research advised by Dr Timothy BONEBRAKE (HKU), Dr Caroline DINGLE (HKU), and Yik-Hei SUNG (Lingnan University). The team working in the field, taking measurements and samples from a tokay gecko. Credits to Tsz Chun SO. The team working in the field, taking measurements and photographs of a tokay gecko. Credits to Tsz Chun SO.   The project The project aimed at answering three main questions: (i) Where do TCM tokay geckos sold in Hong Kong originate? (ii) In which conditions were they raised? and (iii) Where do Hong Kong wild tokays originate? To answer those questions, the research team used a combination of field and lab approaches. They first collected tissue samples from wild tokay geckos across Hong Kong, and from dried individuals sold in TCM shops. Using phylogenetic analysis, they compared their DNA sequences to sequences from all over Asia. They found that TCM tokays nearly all originated from Southeast Asia and not from Hong Kong wild populations. These results were confirmed via stable isotope analysis investigating their food source. However, the results revealed the poor traceability of tokays throughout the supply chain, with individuals sold as pairs originating from two different locations and a single label. This was further complemented by interviews of shopkeepers throughout Hong Kong. This study also revealed that two subspecies of tokay geckos are present at the same time in Hong Kong: Gekko gecko gecko and Gekko gecko reevesii. The latter group included most of individuals observed and were genetically closer to populations in Southern Mainland China. However, two populations in Hong Kong were more closely related to populations in Southeast Asia (G. gecko gecko), likely indicating at least two separate events of introduction of Southeast Asian tokay geckos and establishment in Hong Kong, potentially through the pet trade. Tokay gecko (Gekko gecko reevesii) holding on a stick in the field. Credits to Tsz Ching KONG. Details of the heads of dried tokay geckos. Credits to Sam WEBSTER. Details of dried tokay geckos sold as TCM. Credits to Sam WEBSTER.   Consequences for conservation With millions of tokay geckos being traded every year and only a very recent (2019) listing on CITES Annex II, this species is more vulnerable than its historic abundance might suggest. While farming has been proposed as a potential solution to overharvesting, recent reports have demonstrated the unlikeliness of operating large-scale farms, practically or sustainably. “Events of poaching, at large or small scales, can have major implications on the long-term survival of small populations as they decrease genetic diversity and arbitrarily remove adaptive potential, which is extremely important for species facing multiple challenges. In similar ways, events of release can also trigger short- and long-term perturbations on the genetic diversity at the local and global scale, which is why knowledge of population genetics is crucially needed for evaluating the status of this species, and the appropriate conservation measures throughout its range,” said Dr Pauline DUFOUR, the first author of the study.   Dr Yik-Hei SUNG, an Assistant Professor from Lingnan University, herpetologist, and co-author on the paper further stated that “this study highlights the need for more stringent control of mercy/abandoned pet release”. Indeed, the pet trade is the leading cause of the introduction of exotic reptiles in the world. Dried tokay geckos on stick for sale in Hong Kong. Credits to Pauline DUFOUR.  Funding This project was supported by Ocean Park Conservation Fund (2020-2021) and Hong Kong Postgraduate Fellowship (2017-2021).   Article Citation Dufour PC, Miot EF, So TC, Tang SL, Jones EJ, Kong TC, Landry Yuan F, Sung YH, Dingle C, & Bonebrake TC. 2022. Home and hub: pet trade and traditional medicine impact reptile populations in source locations and destinations. Proc. R. Soc. B 289: 20221011. https://doi.org/10.1098/rspb.2022.1011   * Hong Kong Protection of Endangered Species of Animals and Plants Ordinance (Amendment of Schedules 1 and 3) Order 2021

NEWS DETAIL

Three academics from the Faculty of Science have been selected for Research Grants Council’s Senior Research Fellow Scheme and Research Fellow Scheme

NEWS DETAIL

Discovery of the oldest visible planetary Nebula hosted by a 500-million- year-old Galactic cluster – a rare beauty with a hot blue heart

An international team of astronomers led by members of the Laboratory for Space Research (LSR) and Department of Physics at The University of Hong Kong (HKU), have discovered a rare celestial jewel–a so-called Planetary Nebula (PN) inside a 500 million-year-old Galactic Open Cluster (OC) called M37 (also known as NGC2099). This is a very rare finding of high astrophysical value. Their findings have just been published in the prestigious open-access paper Astrophysical Journal Letters. PNe are the ejected, glowing shrouds of dying stars that shine with a rich emission line spectrum and display, as a result, their distinct colours and shapes that make them photogenic magnets for public interest. It was no coincidence that one of the first James Webb Space Telescope (the largest optical telescope in space) images released to the public was a PN! Figure 2. Fig. 2a left panel: An enhanced 6.5 x.5 arcminute colour-composite RGB image of PN IPHASX J055226.2+323724 from the IPHAS survey (Drew et al. 2005) that we confirm as a physical member of the Galactic open cluster M37. Red = Hα, Green = broad band red and Blue = broad band ‘i’. The CSPN is circled in blue; Fig. 2b right panel: 190 x145 arcsecond RGB image created from SDSS with red = i, green = r and blue = g-band. These data clearly shows the faint CSPN (arrowed) at the centre. North is top and East is to the left in both images.   The PN, with the rather ungainly name of “IPHASX J055226.2+323724”, is only the 3rd example of an association between a PN and an OC out of the ~4,000 PNe known in our Galaxy. It also appears to be the oldest PN ever found. The small team led by Professor Quentin PARKER, Director of the HKU LSR, have determined some interesting properties for their discovery: the authors found the PN has a “kinematic age” of 70,000 years. This estimate is based on how fast the nebula is expanding, as determined from the PN emission lines, and assuming this speed has remained effectively the same since the beginning, and is the time elapsed since the nebular shell was first ejected by the host, a dying star. This compares to typical PN ages of 5,000-25,000 years. It is truly a grand old dame in PN terms but of course a mere “blink of the eye” in terms of the life of the original star itself that runs to hundreds of millions of years. Because this “grand old dame” lives in a stellar cluster, this environment enables the team to determine powerful additional parameters not possible for the general Galactic PN population. These include estimating the mass of the PN’s progenitor star when it turned off the stellar main sequence, as derived from the observed properties of the thousands of stars in the cluster when plotted in a so-called colour-magnitude diagram. The team can also estimate the residual mass of the central star that ejected the PNe via theoretical isochrones and observed properties of the hot, blue central star. As a result, they figured how massive the star was that ejected the PN gaseous shell when it was born and how much mass is now left in its residual, contracting hot core (which is already a so-called ‘White Dwarf’ star). Fresh “Gaia” data for the hot blue, PN central star also provide a good distance estimate allowing the PN’s actual size at this extreme age to be determined as 3.2pc (parsec, an astronomical unit of measure for interstellar space with 1pc equals to 3.26 light-years) in diameter – unsurprisingly perhaps also at the extreme end of known PN physical sizes.   Figure 3. A combined 1-d continuum subtracted example PN spectrum from March 4th 2022 for IFU pointings a, b, c and d from the paper. The 5 visible PN emission lines are labeled. Figure 4. Cluster Gaia DR3 CMD (B versus B-R) diagram fitted with a Padova theoretical isochrone (Bressan et al. (2012), Marigo et al. (2013) for adopted cluster parameters (age = 470 +/- 50 Myrs, reddening E(B−V ) = 0.26 +/-0.04, distance = 1.49 +/- 0.13 kpc and metallicity [Fe/H] = 0.03 +/- 0.28). The CSPN is indicated by the red filled symbol. Stars with >80% probability (Cantat-Gaudin et al. 2018) of being a cluster member, where cross-correlated with Gaia DR3 and are plotted as green dots. The CMD includes all stars with pmRA =0 to 4 and pmDec = −8 to −2 mas/yr (most probable cluster members based on mean proper motions) within 15 arcminutes from the cluster’s apparent center.   Figure 5. A plot from the known sample of cluster white dwarfs for the latest IFMR estimates and semi-empirical ‘PARSEC’ fit (Cummings et al. 2018) together with our estimated point for PN IPHAS J055226.2+323724 plotted as a red circle. The other two points from known open-cluster PNe are plotted as a yellow circle (PHR 1315-6555 (Fragkou et al. 2019a) and (Parker et al. 2011)) and green circle (BMP J1613-5406 - Fragkou et al. (2019c)). The errors attached to our point reflect the errors in the adopted cluster parameters and the spread of the estimated central-star magnitudes. Former HKU PhD student Dr Vasiliki FRAGKOU, the first author of the study stated, “I am so excited to be able to work on these fascinating rare cases of OC-PN associations because they keep turning up important science results, like all three cases we have found are butterfly (bi-polar) PN in terms of shape, all are very faint and highly evolved, and all have Type-I chemistry according to their emission lines, and of course all have intermediate to high progenitor masses.” Corresponding author Professor Quentin Parker said, “This is only the third example of a PN found in a Galactic open star cluster, and my group has found all three confirmed examples. They are incredibly rare but also very important as these beautiful objects allow us to independently determine points on the so called initial to final mass relation (IFMR) for stars – an important astrophysical relation –  independent of the traditional method of using white dwarfs in clusters.  Intriguingly, all our points lie just below the empirical IFMR trend currently established but add to the “kink” in this relation found recently in the 2-3 Solar mass range for the original progenitor mass by Marigo et al in the Nature Astronomy journal. Our OC-PN points fortuitously are found in currently sparsely populated regions of the IFMR, making them even more valuable.” Co-author Professor Albert ZILJSTRA, Hung Hing Ying Distinguished Visiting Professor in Science and Technology at HKU LSR from the University of Manchester commented on the PN visibility lifetimes which have previously been much shorter in the general Galaxy. “This new result implies that the location of a PN in an OC provides an environment suitable for allowing the PNe to expand and fade without disruption by the ambient ISM (which is typically much weaker in an OC) and not as would be the case in the Galaxy.”   About LSR The LSR is well situated in a dynamic region of Asia to foster links with the astrophysics, space and planetary sciences community in China and globally. The LSR’s interdisciplinary research launches various bids to exploit and access the emerging Mainland funding and research environment. We have developed multilateral and strategic partnerships with world-leading universities, space science institutes and participate in large, international, high-impact space missions. 

NEWS DETAIL

Four young scientists awarded the National Excellent Young Scientists Fund 2022

NEWS DETAIL

Distinguished HKU mathematician Professor Ngai-Ming MOK awarded the 2022 Future Science Prize in Mathematics and Computer Science

NEWS DETAIL

New global map of ant biodiversity reveals areas that may hide undiscovered species

Ants are essential for the functioning of ecosystems as they play vital roles, from aerating soil to dispersing seeds and nutrients to scavenging and preying on other species. Yet a global view of their diversity is lacking.  Dr Benoit GUÉNARD of The School of Biological Sciences (SBS) of The University of Hong Kong (HKU) in collaboration with an international team of researchers from the Okinawa Institute of Science and Technology Graduate University (OIST), Japan, and multiple institutes around the world, has developed the first high-resolution map in the world that combines existing knowledge with machine learning to estimate and visualise the global diversity of ants. The study provided a ‘treasure map’ as a guide to explore new species and help conserve the global diversity of ants. The maps and dataset are presented in an article published in Science Advances.    An ant (species: Ectatomma tuberculatum) photographed in Costa Rica. Ants make up a large fraction of the total animal biomass in most terrestrial ecosystems, but researchers say that an understanding of their global diversity is lacking. This new study provides a high-resolution map that estimates and visualizes the global diversity of ants. Photo credit: Dr Benoit Guénard They are hunters, farmers, harvesters, gliders, herders, weavers, and carpenters. They are ants, and they are a big part of our world, comprising over 14,000 species and a large fraction of animal biomass in most terrestrial ecosystems. Like other invertebrates, ants are important for the functioning of ecosystems. However, a global view of their diversity is lacking, which led to difficulties in identifying high diversity centres of invertebrates for future research. As the co-first author, Dr Benoit Guénard from HKU SBS started this decade-long project with Professor Evan ECONOMO of OIST to create a database of occurrence records for different ant species from online repositories, museum collections, and around 10,000 scientific publications. Researchers around the world contributed and helped identify errors. More than 14,000 species were considered, which varied dramatically in the amount of data available. ‘The diversity of insects is phenomenal, representing more than half of all species on Earth. We thus needed to include insects into our global understanding of biodiversity and not to limit ourselves to vertebrate groups which are conspicuous and popular, but from which questioning existed about their representativeness of biodiversity more generally. For several reasons, ants were an ideal group for this’ said Dr Benoit Guénard of HKU SBS.  ‘This study helps to add ants, and terrestrial invertebrates in general, to the discussion on biodiversity conservation,’ said Professor Evan Economo, who leads the Biodiversity and Biocomplexity Unit. ‘We need to know the locations of high diversity centres of invertebrates so that we know the areas that can be the focus of future research and environmental protection.’ Professor Economo added that the resource would also serve to answer a number of biological and evolutionary questions, such as how life diversified and how patterns in diversity arose. However, while containing a description of the sampled location, the vast majority of these records did not have the precise coordinates needed for mapping. To address this, the team built a computational workflow to estimate the coordinates from the available data, which also checked all the data for errors, and they also made different range estimates for each ant species depending on how much data was available. For species with less data, they constructed shapes surrounding the data points. For species with more data, the researchers predicted the distribution of each species using statistical models that they tuned for optimal complexity. The researchers brought these estimates together to form a global map, divided into a grid of 20 km by 20 km squares, that showed an estimate of the number of ant species per square (called the species richness). They also created a map that showed the number of ant species with very small ranges per square (called the species rarity). In general, species with small ranges are particularly vulnerable to environmental changes.  However, there was another problem to overcome—sampling bias. So, the researchers utilised machine learning to predict how their diversity would change if they sampled all areas around the world equally and, in doing so, identified areas where they estimated many unknown, unsampled species exist.  A map highlighting species rarity—the areas with many ant species with very small ranges. The colored areas all indicate important regions for ant species with small ranges. Red indicates areas that are relatively more studied than other areas, which could artificially boost their importance.  Purple areas are both important based on current knowledge and are likely to remain so after future sampling. Blue areas are predicted by machine learning to harbor concentrations of undiscovered, small-ranged ant species, giving scientists a treasure map to guide future exploration. This image is an edited version of figures that appear in the paper.     This map highlights ant biodiversity centers in Asia—areas that harbor many ant species with small ranges. The different colors indicate how the importance of each region may change with future research around the globe. Red areas are predicted to decrease in importance, purple areas will remain among the most important regions even after more areas are studied, and blue indicates areas that should be targets for exploration as they are predicted to harbor hidden diversity. This is a modified version of a figure in the paper.   Professor Economo said, ‘This gives us a kind of treasure map, which can guide us to where we should explore next and look for new species with restricted ranges. When the researchers compared the rarity and richness of ant distributions to the comparatively well-studied amphibians, birds, mammals, and reptiles, they found that ants were about as different from these vertebrate groups as the vertebrate groups were from each other, which was unexpected given that ants are evolutionarily highly distant from vertebrates. This is important as it suggests that priority areas for vertebrate diversity may also have a high diversity of invertebrate species. But, at the same time, it is necessary to recognise that ant biodiversity patterns have unique features. For example, the Mediterranean and East Asia show up as diversity centres for ants more than vertebrates, and these are very important region for conducting future surveys and research. Finally, the researchers looked at how well-protected these areas of high ant diversity are. They found that it was a low percentage—only 15% of the top 10% of ant rarity centres had some sort of legal protection, such as a national park or reserve, which is less than existing protection for vertebrates. ‘This work focused on the species already described, meaning known by Science, however, it is likely that as many ant species remain unknown to this day. Supporting research and infrastructures like museums that facilitate and accelerate the descriptions of this fully unknown part of diversity should be perceived as a top priority, especially within tropical regions where most of biodiversity is concentrated.’ concluded Dr Benoit Guénard. This article was adapted from the original drafted by the Okinawa Institute of Science and Technology (OIST), Japan.  

NEWS DETAIL

HKU marine scientists unveil sea urchin's secret to surviving marine heatwaves

Heliocidaris population in Sydney, Australia. Sea urchins play a key role in maintaining the function of ecosystems, but the fate of future populations is under threat due to increases in the occurrence of marine heatwaves. Photo credit: Dr Maria Byrne Global ocean temperatures are increasing due to climate change, exposing ecosystems to extreme temperatures called marine heatwaves (MHWs), which can increase the temperature of marine waters by 5°C higher than normal in summer. MHWs can last several months and cause devastating effects on marine organisms. Dr Bayden D. RUSSELL from The Swire Institute of Marine Science (SWIMS) and The School of Biological Sciences (SBS) at The University of Hong Kong (HKU), along with his research group, in collaboration with Dr Maria BYRNE, from the Sydney Institute of Marine Science, The University of Sydney (USyd), experimentally assessed whether adult sea urchins (Heliocidaris erythrogramma) that are exposed to marine heatwaves could pass beneficial protective mechanisms onto their offspring, thus ensuring the survival of the next generation. The findings indicated that adult sea urchins could pass on this heatwave resistance to the next generation. However, the study also identified that these carryover effects may not remain effective throughout the development and growth of juvenile urchins. The findings have been published in Global Change Biology.   Sea urchins are both economically and ecologically valuable. They maintain the structure and function of benthic marine ecosystems by eating algae that would otherwise take over these systems in the absence of urchins, making the ecosystem simpler and less biodiverse. This role is particularly important in ecosystems stressed by human activities like nutrient pollution or marine heatwaves, which benefit fast-growing algae that replace critical habitats like coral reefs or larger seaweed forests (e.g., kelp forests). Therefore, the continued survival of sea urchins under global heating is key to the continued function of many marine ecosystems. This current research identified that the ability of urchins to survive extreme conditions through physiological adaptation, and pass on this resistance to the next generation fundamentally depends on their heat tolerance limits. When exposed to thermal stress, some urchin species have the ability to pass on protective mechanisms to their offspring as a means of defence should the offspring come up against the same type of stress as their parents. However, whether these ‘carryover effects’ remain effective throughout the development and growth of  juvenile urchins and therefore allow them to survive till adulthood, can vary widely. Importantly, the research identified that different life stages can have very different abilities to cope with thermal stress; so, the responses seen in offspring may be different to that observed in their parents. The research exposed adult sea urchins to different strengths of marine heatwaves and then spawned the adults under these conditions. The offspring were then reared across a range of temperatures, and their development was tracked to assess for carryover effects from the parents to their offspring. Surprisingly, heatwave-conditioned parents produced faster growing, larger and more heat tolerant offspring. If heatwaves continued, however, there was high mortality in offspring. ‘If a MHW occurs at any time during the spawning period of the urchins, these carryover effects could lead to increased survival of the juveniles under what would normally be stressful temperatures. But, if the heatwave continues throughout the larval development, these short-term physiological responses may lead to higher mortality and ultimately reduce the survival of the next generation,’ said Dr Jay MINUTI, the lead author of the study and postdoctoral researcher at HKU SWIMS & SBS. Therefore, as these types of extreme events become more frequent and intense under climate change, the beneficial carryover effects of parental conditioning to MHWs will only protect the more sensitive juvenile stage and enhance survival if ocean conditions return promptly to normal temperatures. ‘These findings are key for our understanding of what some marine ecosystems might look like under climate change,’ said Dr Bayden Russell. ‘Sea urchins play a key role in maintaining the function of ecosystems, so if the parents can help their offspring survive the extreme temperatures in marine heatwaves, then this may help overall ecosystem function. Unfortunately, it is clear that the only way to stop heatwaves from becoming worse is to reduce the effects of climate change by reducing carbon emissions. If we don’t, then it is becoming clear that heatwaves will devastate marine ecosystems which are important for human society.’ ‘The species of urchin that we used, Heliocidaris erythrogramma, is native to Australia and is ecologically important in near-shore areas,’ said Professor Maria Byrne at USyd, who uses Heliocidaris as a model species to investigate climate change impacts. ‘Its fast development is key to its success in nature, but also provides opportunities for trans-generational research to understand how marine species might adapt to climate change.’ With many species of Heliocidaris urchins being ecologically and economically important worldwide (including Hong Kong), this research provides a first key insight into how the next generation could be protected by their parents from the negative effects of extreme temperatures caused by climate change. The journal paper can be accessed from here.   

NEWS DETAIL

Distinguished Mathematician Professor Ngai-Ming MOK being awarded the Chern Prize

NEWS DETAIL

Professor Vivian Wing-Wah YAM earned another signature accolade: The InnoStars Award

NEWS DETAIL

HKU Laboratory for Space Research put a positive spin on the Buckyball ‘C60’: Its potential for high level ionisation and as the origin for some of the Mysterious Unidentified Infrared Emission Bands seen in the Universe

Is there now at long last some plausible theoretical basis for the molecular origins and carriers of at least some of the most prominent so called ‘UIE’ (unidentified Infrared Emission) bands that have mystified astronomers for decades?   The theoretical astrophysicists and astrochemists at the Laboratory for Space Research (LSR) and Department of Physics at The University of Hong Kong (HKU) seem to think so (at least in theory) in a peer-reviewed paper just published in the prestigious ‘The Astrophysical Journal.’   A team led by Dr SeyedAbdolreza SADJADI, member of the LSR, and Professor Quentin PARKER, Director of the LSR in the Department of Physics, has now placed some interesting theoretical work into the mix. It identifies highly ionised species of the famous football shaped ‘Buckminster’ fullerene C60 molecule as plausible carriers of at least some of the most prominent and enigmatic UIE bands that have challenged astronomers since they were first discovered and studied over 30 years ago.   First, Dr Sadjadi and Professor Parker proved theoretically that C60 could survive, in stable states, from being ionised up to +26 (i.e. 26 of the 60 electrons in the buckyball being removed) before the buckyball disintegrates (Sadjadi & Parker 2021). Now they have shown, via applying first principles quantum chemical calculations, what theoretical mid-infrared signatures of these ionised forms of fullerene can be expected. The results are extremely interesting and provocative and may at last point the way forward to at least a partial resolution of this enduring astrophysical mystery.   Professor Parker said, ‘I am extremely honoured to have played a part in the astonishingly complex quantum chemistry investigations undertaken by Dr Sadjadi that have led to these very exciting results. They concern first the theoretical proof that Fullerene–Carbon 60–can survive to very high levels of ionisation and now this work shows the infrared emission signatures from such species are an excellent match for some of the most prominent Unidentified Infrared Emission features known. This should help re-invigorate this area of research.’   The HKU lead team found that some of these positively charged fullerenes show strong emission bands that match extremely well the position of key astronomical UIE emission features at 11.21, 16.40 and 20-21 micrometers (μm). This makes them key target species for identification of the currently unidentified UIE features and provides strong motivation for future astronomical observations across the mid infrared wavelength range to test these theoretical findings. They also found that the IR signatures of the group of these C60 cations with q = 1 − 6 are well separated from the 6.2 μm bands, that are associated with free/isolated aromatic hydrocarbon molecules (so called PAH’s, another potential carrier of UIE). This significantly aids in their identification from other potential carriers. This finding is particularly important for discrimination and exploration of the coexistence of complex hydrocarbon organics and fullerenes in astronomical sources.   Dr Sadjadi said, ‘In our first paper we showed theoretically that highly ionised fullerenes can exist and survive the harsh and chaotic environment of space. It is like asking how much air you can push out of a football ball and the ball still maintains its shape. In this paper we worked with two other leading astrophysicists and planetary scientists Professor Yong ZHANG and Dr Chih-Hao HSIA , both ex-HKU staff but still affiliated to the LSR, to determine the molecular vibrational notes of a celestial symphony, ie the spectral features that these ionised buckyballs would play/produce. We then hunted for them in space showing their notes/signatures are easily distinguishable from PAHs.’   The journal paper can be accessed here: https://iopscience.iop.org/article/10.3847/1538-4357/ac75d5   Captions:   Solar system illustration of the C60 and some of its highly positively charged cations, representing theoretically calculated normal modes vibration motions and relative molecular sizes (volumes). C6010+, the little bucky, is the only charged fullerene inherited from the symmetry of C60. The bottom right corner is the theoretically predicated IR fingerprint of this exotic species (brown profile), overlapped onto the astronomically observed emission spectrum of Tc1 planetary nebula within the same wavelength region. Image Credit: SeyedAbdolreza Sadjadi and Quentin Andrew Parker   Reference: 1. It remains a cage: ionisation tolerance of C60 fullerene in planetary nebulae Sadjadi, SeyedAbdolreza ; Parker, Quentin Andrew  in Fullerenes, Nanotubes and Carbon Nanostructures, vol. 29, issue 8, pp. 620-625; Pub Date:August 2021

NEWS DETAIL

Renowned Chemist Professor Vivian Wing-Wah YAM being awarded the Silver Bauhinia Star

NEWS DETAIL

Dr Joseph Michalski elected as a Fellow of the Geological Society of America 2022

NEWS DETAIL

HKU physicists found signatures of highly entangled quantum matter

A research team from the Department of Physics, The University of Hong Kong (HKU), discovered the clear evidence to characterise a highly entangled quantum matter—the quantum spin liquid (QSL) (a phase of matter that remains disordered even at very low temperatures) from large-scale simulations on supercomputers. This pivotal research work has recently been published in one of the leading journals in quantum materials—npj quantum materials. QSLs were proposed by P. W. Anderson—the Nobel Physics Laureate of 1977—in 1973, which had the potential to be used in topological quantum computing to bring the computing power of computers to a new stage, and to help understand the mechanism of high temperature superconductors, that could greatly reduce the energy cost during electricity transport owing to the absence of electrical resistance in superconductors.   The QSL is termed a liquid due to its lack of conventional order in the matter. QSLs have a topological order that originates from long-range and strong quantum entanglement, while the detection of this topological order is a very tough task due to the lack of materials that can perfectly achieve the many model systems that scientists propose to find a topological order of QSL and prove its existence. Thus, there has not been firmly accepted concrete evidence showing QSLs exist in nature. Under this context, Mr Jiarui ZHAO, Dr Bin-Bin CHEN, Dr Zheng YAN, and Dr Zi Yang MENG from HKU Department of Physics, successfully probed this topological order in a phase of the Kagome lattice quantum spin model, which is a two-dimensional lattice model with intrinsic quantum entanglement and proposed by scientists that have Z2 (a cyclic group of order 2) topological order, via a carefully designed numerical experiment on supercomputers. Their unambiguous results of topological entanglement entropy strongly suggest the existence of QSLs in highly entanglement quantum models from a numerical perspective. ‘Our work takes advantage of the superior computing power of modern supercomputers, and we use them to simulate a very complicated model which is thought to possess topological order. With our findings, physicists are more confident that QSLs should exist in nature,’ said Mr Jiarui Zhao, the first author of the journal paper and a PhD student at the Department of Physics. ‘Numerical simulations have been an important trend in scientific research of quantum materials. Our algorithms and computations could find more interesting and novel quantum matter and such efforts will surely contribute to the development of both practical quantum technology and the new paradigm in fundamental research.’ Dr Zi Yang Meng, Associate Professor in the Department of Physics remarked. The research The team designed a numerical experiment on the Kagome spin model (Kagome is a two-dimentional lattice structure that shows a similar pattern to a traditional Japanese woven bamboo pattern in the shape of hexagonal latticework) in the proposed QSL phase, and the schematic plot of the experiment is illustrated in Figure 2. The entanglement entropy (S) of a system can be obtained by measuring the change of the free energy of the model during a carefully designed nonequilibrium process. The topological entropy (γ), which characterises long-range topological order, can be extracted by subtracting the short-range contribution, which is proportional to the length of the entanglement boundary (l) from the total entanglement entropy(S), by fitting the data of entanglement entropy of different entanglement boundary length to a straight line (S=al-γ).   The schematic plot of the numerical experiment.   As shown in Figure 3, the team conducted the experiment on two kinds of lattices with different ratios of length and width to ensure the reliability of the results. We use a straight line to fit the relation between the entanglement entropy with the length of the entanglement boundary so that the topological entropy should equal the intercept of the straight line. Our results give the value of topological entropy to be 1.4(2), which is consistent with the predicted value of topological entropy of a Z2 quantum spin liquid, which is 2ln (2). Our findings confirm the existence of QSLs from a numerical perspective.   The lattice types of the Kagome quantum spin model and the corresponding results of topological entropy.   About the research team This research is a collaborative effort between the three authors—Mr Jiarui Zhao, Dr Bin-Bin Chen, and Dr Zheng Yan from HKU Department of Physics, under the supervision of Dr Zi Yang Meng from the same affiliation. The work was supported by the Research Grants Council of HKSAR, the Areas of Excellence ‘2D Materials Research: Fundamentals Towards Emerging Technologies’, the Seed Funding Quantum-Inspired explainable-AI at the HKU-TCL Joint Research Centre for Artificial Intelligence. We thank the Information Technology Services and the HPC2021 supercomputer in HKU, and the National Supercomputer Centre in Guangzhou (Tianhe-II supercomputer) for their technical support and for providing generous HPC resources that have contributed to the research results reported within this paper.   The journal paper can be accessed here: https://www.nature.com/articles/s41535-022-00476-0

NEWS DETAIL

PhD student of HKU Chemistry won the Langmuir Best Oral Presentation Award (3rd place)

PhD student Dengping LYU of HKU Chemistry was awarded the Langmuir Best Oral Presentation Award (3rd place), at the 96th ACS Colloid and Surface Science Symposium (CSSS), a top international conference in the field held from 10-13 July at Colorado School of Mines, USA. The prestigious award, sponsored by the ACS journal Langmuir and the ACS Division of Colloid and Surface Chemistry, aims to recognise excellence in research of postgraduate students as manifested in oral presentations.   In her presentation, titled “Introducing Patchy MOF Particles for Precise, Hierarchical, and Reconfigurable Colloidal Self-Assembly”, Dengping demonstrated the synthesis of a new type of low-symmetry, anisotropic particles by exploiting the emerging metal-organic frameworks, which can spontaneously assemble into colloidal superstructures with unprecedented precision. This paves the way for creating smart functional materials with precise control over their architectures at various length scales.     Dengping is a member in the research group led by Dr Yufeng WANG. Another key contributor of this work Mr Wei Xu, is also a HKU PhD student and a member in the same research group.  The work has been recently published in the top Chemistry Journal Angewandte Chemie International Edition: “Low‐Symmetry MOF‐Based Patchy Colloids and Their Precise Linking via Site‐Selective Liquid Bridging to form Supra‐Colloidal and Supra‐Framework Architectures”. Angew. Chem. Int. Ed. 61, e202115076, 2022. 

NEWS DETAIL

HKU Chemist Professor Zheng Xiao GUO Awarded HK$43.011 Million in Theme-based Research Scheme to Achieve Carbon Neutrality

A research project coordinated by Professor Zheng Xiao GUO from Department of Chemistry, was awarded funding of HK$43.011 million in the Theme-based Research Scheme (TRS) 2022/23 (twelfth round) launched by Research Grants Council (RGC), which aims to channel academic research efforts of UGC-funded universities into strategic important areas that promote the long-term development of Hong Kong.   The research takes a multi-disciplinary approach that will help achieve carbon neutrality worldwide by developing technologies that could transform earth-abundant molecules into clean fuels and chemicals.   Professor Guo expressed his delight in being awarded of the funding and described the support came timely and encouraging. ‘It is timely because of the urgent need to combat climate change and achieve carbon-neutrality in coming decades, which requires concerted and focused actions. It is encouraging because our proposal to turn the global challenge to “glocalised” opportunities in Hong Kong has been well recognised for its scientific quality, local relevance, team excellence, and management robustness.’ He also thanked all team members for their collaborative spirit and hard work in securing the award, ‘Of course, the real hard work begins now – we look forward to working together, to contribute to Hong Kong’s social-economic-technological pathways to net-zero.’ More about the project:  Project title: Towards Carbon Neutrality: Catalysing Water and Carbon Dioxide to Green Resource Carriers Achieving carbon neutrality is a global mission. This project contributes by providing carbon-negative technologies that could help reach carbon neutrality targets around the world. The developed technologies could transform earth-abundant molecules, such as (sea) water and carbon dioxide, into clean fuels and chemicals, such as hydrogen and alcohol, utilising renewable solar or wind energy during the conversion. The project also sets the scientific foundation for future research, making it possible to turn molecules in the air into fuels, fertilisers, fabrics, and even food. The research takes a multi-disciplinary approach that could make Hong Kong become a “Green Resources Carriers Hub”.  Click here for more details.

NEWS DETAIL

Experts Predict Top Impacts on Ocean Biodiversity Over Next Decade: Lithium Extraction from the Deep Sea, Overfishing of Deeper-Water Species, and the Unexpected Ocean Impacts of Wildfires on Land are Among Fifteen Issues Experts Warn We Ought to be Addre

An international team of experts including Dr Moriaki YASUHARA from the School of Biological Sciences, The Swire Institute of Marine Science, and Institute for Climate and Carbon Neutrality of The University of Hong Kong (HKU), has produced a list of 15 issues they believe are likely to have a significant impact on marine and coastal biodiversity over the next five to ten years. Their ‘horizon scanning’ technique focuses on identifying issues that are not currently receiving widespread attention, but are likely to become important over the next decade. The aim is to raise awareness and encourage investment into full assessment of these issues now, and potentially drive policy change, before the issues have a major impact on biodiversity. The final 15 issues identified by the team of experts. Image of brine pool courtesy of the NOAA Office of Ocean Exploration and Research, Gulf of Mexico 2014.   The issues include the impacts of wildfires on coastal ecosystems, the effects of new biodegradable materials on the marine environment, and an ‘empty’ zone at the equator as species move away from this warming region of the ocean. “Marine and coastal ecosystems face a wide range of emerging issues that are poorly recognised or understood, each having the potential to impact biodiversity,” said Dr James HERBERT-READ in the University of Cambridge’s Department of Zoology, joint first author of the paper. He added, “By highlighting future issues, we’re pointing to where changes must be made today – both in monitoring and policy – to protect our marine and coastal environments.” The horizon scan involved 30 experts in marine and coastal systems from 11 countries in the global north and south, from a variety of backgrounds including scientists and policy-makers. The results are published today in the journal Nature Ecology and Evolution. Dr Moriaki Yasuhara of HKU School of Biological Sciences said, some of these issues are critically relevant to Hong Kong or Southeast Asia broadly, “For example, the decline of tropical biodiversity due to global warming and resulting in the moving away of tropical species to a higher latitude, may substantially erode the biodiversity of the Coral Triangle, Southeast Asian region of Philippines, Hong Kong to the North, Indonesia to the west, and Papua New Guinea to the east, where are known as the places of highest marine biodiversity in the world. Fancy seafood trades such as fish maw are a serious conservation issue, especially in Hong Kong as the global hub of such trades and Mainland China as the main consumer. So, this marine horizon scan clearly highlighted the importance of conducting more research in Southeast and East Asia, where tend to be understudied.” Several of the issues identified are linked to exploitation of ocean resources. For example, deep sea ‘brine pools’ are unique marine environments home to a diversity of life and have high concentrations of salts containing lithium. The authors warn that rising demand for lithium for electric vehicle batteries may put these environments at risk. They call for rules to ensure biodiversity is assessed before deep-sea brine pools are exploited. While overfishing is an immediate problem, the horizon scan looked beyond this to what might happen next. The authors think there may soon be a move to fishing in the deeper waters of the mesopelagic zone (a depth of 200m – 1000m), where fish are not fit for human consumption but can be sold as food to fish farms. “There are areas where we believe immediate changes could prevent huge problems arising over the next decade, such as overfishing in the ocean’s mesopelagic zone,” said Dr Ann THORNTON in the University of Cambridge’s Department of Zoology, joint first author on the paper. She added, “Curbing this would not only stop overexploitation of these fish stocks, but reduce the disruption of carbon cycling in the ocean, because these species are an ocean pump that removes carbon from our atmosphere.” The report also highlights the potential impact of new biodegradable materials on the ocean. Some of these materials are more toxic to marine species than traditional plastics. Herbert-Read said, “Governments are making a push for the use of biodegradable materials – but we don’t know what impacts these materials may have on ocean life.” The authors also warn that the nutritional content of fish is declining as a consequence of climate change. Essential fatty acids tend to be produced by cold-water fish species, so as climate change raises ocean temperatures, the production of these nutritious molecules is reduced. Such changes may have impacts on both marine life and human health. Not all of the predicted impacts are negative. The authors think the development of new technologies, such as soft robotics and better underwater tracking systems, will enable scientists to learn more about marine species and their distribution. This, in turn, will guide the development of more effective marine protected areas. But they also warn that the impacts of these technologies on biodiversity must be assessed before they are deployed at scale. Early identification of these issues, and their potential impacts on marine and coastal biodiversity, will support scientists, conservationists, resource managers, policy-makers and the wider community in addressing the challenges facing marine ecosystems. While there are many well-known issues facing ocean biodiversity, including climate change, ocean acidification and pollution, this study focused on lesser-known emerging issues that could soon have significant impacts on marine and coastal ecosystems. This horizon scanning process has previously been used by researchers from the Department of Zoology at Cambridge University to identify issues that have later come to prominence, for example, a scan in 2009 gave an early warning that microplastics could become a major problem in marine environments. The United Nations has designated 2021-2030 as the ‘UN Decade of Ocean Science for Sustainable Development.’ In addition, the fifteenth Conference of the Parties (COP) to the United Nations Convention on Biological Diversity will conclude negotiations on a global biodiversity framework in late 2022. The aim is to slow and reverse the loss of biodiversity, and establish goals for positive outcomes by 2050. This research was funded by Oceankind. This press release was adapted from the original version drafted by the University of Cambridge. Reference: Herbert-Read, J.E. et al. A global horizon scan of issues impacting marine and coastal biodiversity conservation. Nature Ecology and Evolution, July 2022. The journal paper can be accessed here.    Supplementary information The full list of issues identified by the report includes: Ecosystem impacts Wildfire impacts on coastal and marine ecosystems Coastal darkening Increased toxicity of metal pollution due to ocean acidification Equatorial marine communities becoming depauperate (lacking variety) due to climate migration Altered nutritional content of fish due to climate change Resource exploitation Untapped potential of marine collagens and their impacts on marine ecosystems Impacts of expanding trade for fish swim bladders on target and non-target species Impacts of fishing for mesopelagic (middle-depth) species on the biological ocean pump Extraction of lithium from deep-sea brine pools Novel technologies Co-location of marine activities Floating marine cities Trace element contamination compounded by the global transition to green technologies New underwater tracking systems to study non-surfacing marine animals Soft robotics for marine research Effects of new biodegradable materials in the marine environment  

NEWS DETAIL

HKU marine scientists join hands with local oyster industry to set up the first oyster hatchery in Hong Kong, cultivating native seeds to sustain oyster aquaculture

Oysters have been an important commodity in Hong Kong for more than 700 years. While serving as a tasty and highly nutritious food source, oysters have also helped to clean and enrich our seawater, and their reefs provide habitat and nursery grounds for many native species that are otherwise lost from our shores. However, the local oyster agriculture in Lau Fau Shan and the surrounding waters of Deep Bay has been severely hindered by coastal modification, the seasonal shift in temperature and salinity due to climate change, pollution and emerging pathogens in the recent years, which not only leads to huge summer and winter mortality of oysters (as high as 80%), but also has affected the livelihood for thousands of growers around the area. As demand for sustainable supply of this precious seafood is rapidly growing, there is an urgency to identify an oyster strain with relatively high-stress tolerance and immune resistance power to overcome at least some of these novel human-induced environmental constraints. In view of this, Marine Scientists at School of Biological Sciences and The Swire Institute of Marine Science (SWIMS) of The University of Hong Kong (HKU),  join hands with the local oyster industry to set up the Hong Kong Oyster Hatchery & Innovation Research Unit, which aims to develop innovative hatchery technology in partnership with growers and industry that re-establishes high-quality natural resources and delivers superior oyster seeds for sustainable coastal aquaculture particularly in South China and Hong Kong. The facility will commence operation in July 2022. On 27th May, 2022, the hatchery and aquaculture experts from the northern, middle and southern part of mainland China gathered at HKU to discuss the oyster hatchery and its relevance for sustainable aquaculture with Hong Kong’s oyster growers, government agency, industry, NGOs, researchers, and other stakeholders, in order to identify ways through which the proposed oyster hatchery could be integrated with national effort to develop sustainable oyster aquaculture with a global perspective. The project received 5.28 million funding from the Sustainable Fisheries Development Fund (SFDF) of the Agriculture, Fisheries and Conservation Department (AFCD), and 3 million generous donation from Lee Kum Kee Company Limited. Under their support, an oyster hatchery at a research scale will be set up at HKU campus, using novel hatchery technologies to enhance oyster seed production. After the settlement of the oyster spat, the final stage of seed production will be taken place at the laboratory of SWIMS, which is located in the Cape D’Aguilar marine reserve, where the seeds will be maintained and monitored for few weeks before supplying to local growers. The laboratory set up at The Hong Kong Oyster Hatchery The hatchery at HKU Campus contains an Algal Culture area to supply adequate food for the nursery culture of both oyster larvae and spats in the hatchery room. A Larval Culture area made the major part of the hatchery, which has its own re-circulation facility for over 2000L of seawater and supports larval settlement and spat culture facility. A significantly large Chemical Lab area for studying oyster meat quality and food safety parameters.   The project aims to produce oyster seeds of three local oyster species: Crassostrea hongkongensis (Hong Kong oysters), Crassostrea ariakensis (Suminoe oysters) and Crassostrea angulata (Portuguese oysters), and estimates to produce 10,000 strings of oyster seeds, with each string holding 200 good quality oysters approximately per year. The trial seed production will start in summer 2022, and full-scale seed production is expected to be done by summer 2023. Local stakeholders, including oyster growers, will adopt the technology for their oyster production by the year 2024. Building these innovative tools would help local growers and government authorities to modernise the oyster aquaculture industry in the region, hoping to have a direct impact, particularly in South China and Hong Kong. Mr CHOW Wing Kuen, Senior Fisheries Officer (Aquaculture Fisheries) of the AFCD noted, “Oyster hatchery will demonstrate the feasibility and economic viability of local oyster seeds production, which ensures faster growth of disease-resistant local strains, and improve the livelihood of local oyster farmers.” Mr CHUNG Shiu Cheong, General Manager of Oyster Hatchery (China) said on behalf of Lee Kum Kee Company Limited, that the company would continue to seize every opportunity to contribute to the society, “We are honoured to have this opportunity to collaborate with the research team at HKU which specialises in oceanology and marine science. We truly believe it will lead the local oyster industry to a bright and successful future.” Professor Vivian Wing-Wah YAM, HKU Dean of Science (Interim) and Philip Wong Wilson Wong Professor in Chemistry and Energy appreciated the collaboration between HKU Marine Scientists and the industry, “I am delighted to have representatives from local oyster growers, the government, industry, NGOs and student entrepreneurs gathering to develop a strong interlined network of collaborations and knowledge exchange involving all stakeholders and importantly, local industry and to discuss and identify ways to tackle and overcome the challenges.” Dr Thiyagarajan VENGATESEN of HKU School of Biological Sciences and The Swire Institute of Marine Science, who took the lead in setting up the Hong Kong Oyster Hatchery & Innovation Research Unit said, the hatchery was designed not only for oyster seed production but also as a platform for research, education, and knowledge exchange, “We hope that this oyster hatchery will foster interdisciplinary research to modernise the green carbon neutral oyster aquaculture industry, as well as networking with global leaders to identify quality breed that contains trait of interest using big data and machine learning tools.” At the kick-off meeting of The Hong Kong Oyster Hatchery and Innovation Research Unit, the hatchery and aquaculture experts, local oyster industry, government agency and other stakeholders gathered to discuss the sustainability of Oyster aquaculture in Hong Kong. From the left: Mr CHUNG Shiu Cheong, General Manager of Oyster Hatchery (China), Mr Brian LEE (Director of Manufacturing) and Mrs Elizabeth MOK (Technical Service Director) of Lee Kum Kee Company Limited; Professor Vivian Wing-Wah YAM, HKU Dean of Science (Interim) and Philip Wong Wilson Wong Professor in Chemistry and Energy; Mr CHOW Wing-Kuen, Senior Fisheries Officer (Aquaculture Fisheries) of Agriculture, Fisheries and Conservation Department; Dr Thiyagarajan VENGATESEN of HKU School of Biological Sciences and The Swire Institute of Marine Science; Mr Fung CHAN of Hong Kong Oyster Company Limited.  

NEWS DETAIL

HKU Astrophysicist Professor Quentin Parker and His Collaborators Awarded the 2022 Gemini Prize

Professor Quentin A PARKER, Director of the Laboratory for Space Research (LSR) at The University of Hong Kong, together with his collaborator, Pascal Le Dû, amateur astronomer and 2SPOT association President, as well as amateur astronomers and members of the 2SPOT association Thomas Petit, Lionel Mulato and Olivier Garde, are awarded Le Prix Gemini 2022 (the 2022 Gemini Prize) co-organised by La Société astronomique de France (SAF) and Société Française d’ Astronomie et d’Astrophysique (SF2A), for their project ‘Search for and Confirmation of Planetary Nebulae Candidates’. ‘I feel honoured and humbled to receive this international recognition of the importance of our professional astronomical work with our French amateur colleagues in the discovery and confirmation of a significant new sample of Galactic Planetary Nebulae (the beautiful glowing shrouds of low mass dying stars). This “prix Gemini” is a fitting reward for the more than a decade of work of many of my close French amateur colleagues, led by Pascal Le Dû, in this incredible pro-am endeavour of scientific discovery, and I am proud to have played a role in their great pursuit,’ said Professor Parker. The prize (medal, diploma and cash award), which is set up to reward outstanding collaboration between professionals and amateurs in astronomy and related sciences, will be delivered during the SF2A Symposium to be held in Besancon, France, on June 10, 2022. A talk will be given by the awardees during the Gemini Pro-Am workshop on the same day. The project also has an opportunity to publish a paper in a coming issue of L’Astronomie magazine, an edition of Société astronomique de France, by the year end of 2022. About the Project This prestigious award results from an intensive and coordinated ten-year observational pro-am program designed to uncover and confirm Galactic Planetary Nebulae (PNe). This has been undertaken by a dedicated group of largely French amateur astronomers led by Pascal Le Dû in collaboration with professional colleagues led by Professor Quentin Parker. This group has so far uncovered 209 spectroscopically confirmed Galactic PNe. These discoveries represent ~5% of all 3831 Galactic PNe currently known according to the HASH (Hong Kong AAO Strasbourg H-alpha Planetary Nebula) PNe database. This award recognises the power and value of the amateur community in undertaking a coordinated and focused program such as this with their professional counterparts. About Professor Quentin Parker and Laboratory for Space Research Quentin Parker joined The University of Hong Kong in 2015 and is currently Director of the Laboratory for Space Research (LSR, see https://www.lsr.hku.hk). Research activities are mainly associated with Wide Field Astronomy, and he has discovered more Planetary Nebulae (PNe) than anyone in history. He has also extensive experience as an astrophysics instrumentalist and has published 571 papers/articles, of which 278 are refereed. These have more than 23475 citations with a h-index of 71. Quentin also has a long-term interest in Chinese Bronze artefacts and cultural heritage, interdisciplinary studies and science pedagogy. More recently, Quentin has been engaged in promoting STEM education from a Space and entrepreneurial direction (see https://cubesat.hku.hk) and is currently Vice Chairman of OASA – the Orion Astropreneur Space Academy (https://www.oasahk.org). He is also an active newspaper opinion piece contributor.

NEWS DETAIL

HKU Conservation Forensics Lab develops novel environmental DNA monitoring method for identifying rare and endangered fish species sold in Hong Kong wet markets

In a paper recently published in Methods in Ecology and Evolution, researchers in the Conservation Forensics Lab at The University of Hong Kong have outlined a powerful new tool for monitoring trade of rare and endangered fish species in Hong Kong wet markets. Using environmental DNA (eDNA) present in the drain runoff water of fish markets, researchers were able to extract and sequence enough DNA to identify over 100 species of fish that had passed through the market. Various types of vulnerable or endangered species were detected by the eDNA method in the study, including Epinephelus fuscoguttatus, a type of brown marbled grouper which is listed as vulnerable and decreasing according to The International Union for Conservation of Nature (IUCN), and three eel species including Anguilla japonica and Anguilla rostrata, which are listed as endangered by IUCN, as well as CITES(Convention on International Trade in Endangered Species of Wild Fauna and Flora)-listed European eel, Anguilla anguilla. Two types of bream were detected including the golden threadfin bream (Nemipterus virgatus) which is listed as vulnerable by the IUCN, and the Okinawa seabream (Acanthopagus sivicolus), listed as vulnerable and decreasing by the IUCN. Metabarcoding Allows Identification of Species At Once Barcoding is a common method of species identification, wherein certain regions of an organism’s genome are sequenced and used to identify the organism in question. Each species has its own unique ‘barcode’, which can provide a more reliable form of identification than traditional morphology-based methods. This technique can be expanded to identifying many species at once (known as metabarcoding) thanks to advanced high-throughput sequencing technology. Even the small amounts of DNA shed from plants and animals into the environment (eDNA) are sufficient for metabarcoding which enables identification of mixed communities of species that may have been present in the area. In this study, researchers in the Conservation Forensics Lab aimed to develop a method for identifying fish species traded in Hong Kong markets that does not rely on having fish taxonomy experts spend hours visually identifying every fish on sale. Further, many fish vendors are often reluctant to permit lengthy inspections of their wares, as endangered fish species can often be found for sale in Hong Kong markets. The method outlined in the paper compared the two most common types of eDNA capture: filtration and precipitation. In the filtration method, one litre of water collected from the drains in three wet markets was collected and passed through a fine filter, which captured tissue, blood, and other cellular debris holding enough DNA to make an identification of the fish species that shed it. The precipitation method used even less water, enabling identification of fish species present by chemical precipitation of eDNA present in cellular debris from 45 ml of drain runoff. After the drain water was collected, eDNA was extracted and sequenced and fish species present in the three wet markets investigated over a 5-day period were identified. To confirm the results, an expert fish taxonomist performed a visual survey, and the overlap of species detections were compared. High Reliability and Easy to Adapt While it is impossible to be 100% certain in identifying every single species present with either method, the advantages of a DNA-based survey method are numerous. Chiefly, DNA-based IDs can be more reliable than morphological IDs, and this is especially true when fish are sold butchered or belong to certain similar-looking genera and families. The DNA extraction method outlined in the paper is also very simple and can easily be executed by anyone with basic molecular lab training of several hours. Visual surveys require hours and hours of extensive work by multiple expert taxonomists, which has been a factor holding back rollout of regular surveys in Hong Kong. ‘We hope that our method will not only encourage local authorities to adopt more high-tech solutions to monitoring and combatting the illegal wildlife trade in Hong Kong, but also help expand the use of eDNA and metabarcoding further into urban contexts,’ said John L RICHARDS, co-author of the journal paper. About HKU Conservation Forensics Lab Working towards the conservation of illegally traded wildlife in Hong Kong, members of the Conservation Forensics Lab at HKU are trained in various tools and techniques for identifying the legality of seized species. In order to support government and conservation efforts in curbing the trade of threatened species, the lab provides a platform for interdisciplinary scientific research and education to the general public. For more information about the Lab, please visit: https://www.ccf-hku.com Link of journal paper: https://besjournals.onlinelibrary.wiley.com/doi/10.1111/2041-210X.13842

NEWS DETAIL

HKU Biologists Reveal a Novel Macrophages-mediated Mechanism that Promotes Peritoneal Metastasis of Ovarian Cancer, Providing Important Insights into Its Therapeutic Strategy

The research discovers that Wnt/b-catenin signalling in metastatic cells upregulates the expression of cancer cells metadherin and communicates with macrophages through CEACAM1. Image modified from original illustration of Adv. Sci. (Weinh) 2022; e21   A research team at the School of Biological Sciences, The University of Hong Kong (HKU), has revealed novel cellular and molecular interactions between cancer cells and tumour-associated macrophages that promote peritoneal metastasis of ovarian cancer. These findings provide important insights into the therapeutic strategy of ovarian cancer and are now published in Advanced Science, a leading interdisciplinary open-access journal.    Background Ovarian cancer is the leading cause of deaths among all gynaecological cancers. Over 70% of patients are diagnosed at an advanced stage with metastatic diseases. Peritoneal metastasis is very difficult to treat due to tumour heterogeneity and the dynamic interactions of cancer cells with the tumour microenvironment. The lack of suitable experimental models has been one significant obstacle to study the cellular and molecular mechanisms of this critical process, and the distinct interactions among different cancer cell subclones and tumour microenvironment are largely unknown using traditional bulk measurement.   Research methods and findings Key findings: In metastatic ovarian cancer cells, Wnt/b-catenin signalling upregulates the expression of metadherin, which communicates with macrophages through CEACAM1, a carcinoembryonic antigen expressed by macrophages, suggesting that blockade of macrophage-tumour communications (by inhibiting either metadherin or CEACAM1) could greatly reduce peritoneal metastasis.   Based on tumour heterogeneity, the research team has previously established an isogenic model that mimics spontaneous ovarian cancer metastasis. Using this model, an upregulation of Wnt/β-catenin signalling was found in the metastatic cells by gene profiling and bioinformatic analyses. Wnt/β-catenin signalling is known to play critical roles in embryonic development, tissue homeostasis and cancer development, since its upregulation increases oncogene expression and facilitates cancer metastasis.   Macrophages play key roles in both the innate and adaptive immunity to orchestrate the concerted immune responses and are the most abundant immune cells in the ovarian cancer tumour microenvironment. Observation of cellular behaviours using single-cell time-lapse microscopy reveals that in the presence of macrophages, a subset of the metastatic cells shows selective advantage of becoming polyploidy, a phenotype that duplicates entire genomes, could promote tumour aggressiveness and therapeutic resistance. On the other hand, the metastatic cells polarise macrophages to a tumour-associated phenotype that reinforces the polyploid phenotype. Further molecular analyses suggest that b-catenin signalling upregulates cancer cell surface metadherin, which communicates through CEACAM1 expressed by macrophages.    The clinical relevance of these scientific findings were further validated by tumour xenografts in mice and patients’ clinical samples. Blocking macrophage-tumour communications via the inhibition of metadherin or CEACAM1 greatly reduced peritoneal metastasis in humanised mouse models which have human immune cells. Since metadherin and CEACAM1 are accessible on the outer surface of cells, they represent highly suitable candidates for tumour cell tracking and clinical targeting.   Research significance The team has made a key discovery of a potential driving mechanism for cancer cell polyploidy and genomic instability, which is initiated through direct interaction with macrophages. Targeting components of the molecular cascade identified in the study holds great therapeutic potential to disrupt polyploidisation of the cancer subclones that drive metastasis.   ‘Our findings are intriguing because few factors that regulate cancer polyploidy have been identified to date, and we have also provided a mechanistic rationale for targeting b-catenin or its downstream signalling molecules to decrease peritoneal dissemination associated with poor prognosis,’said Professor Alice WONG, Director (Interim) of the School of Biological Sciences, who led the research. The team plans to explore in more detail the signalling mechanisms that drive polyploidy in the metastatic cells, as this would greatly enhance the understanding of the genomically unstable disease.    About the research team The research was co-led by Professor Alice Sze Tsai WONG (Director (Interim) of School of Biological Sciences, HKU), and Dr Jue SHI (Associate Professor, Department of Physics, Hong Kong Baptist University (HKBU)). Dr Sally Kit Yan TO (Postdoctoral Fellow, School of Biological Sciences, HKU), was the first author, with the assistance of Dr Maggie Kei Shuen TANG (Postdoctoral Fellow, Laboratory for Synthetic Chemistry and Chemical Biology, InnoHK; Honorary Research Associate, School of Biological Sciences, HKU) and Dr Yin TONG (Postdoctoral Fellow, Department of Pathology, HKU). Other collaborators include Dr Jiangwen ZHANG (Associate Professor, School of Biological Sciences, HKU), Dr Karen Kar Loen CHAN, Clinical Associate Professor, Department of Obstetrics and Gynecology, HKU), and Dr Philip Pun Ching IP (Clinical Associate Professor, Department of Pathology, HKU).   Acknowledgements This work was supported by the Hong Kong Research Grant Council grants (17104820, 17141216, C4041-17G and C2006-17E) and ‘Laboratory for Synthetic Chemistry and Chemical Biology’ under the Health@InnoHK Program launched by Innovation and Technology Commission, HKSAR. Professor Alice WONG is a recipient of the Croucher Foundation Senior Research Fellowship.   Link of journal paper can be accessed from here: https://doi.org/10.1002/advs.202103230   More information about Professor Alice WONG’s work and her research team: https://www.awonglab.com/

NEWS DETAIL

Secondary School Students team up to simulate production of “CubeSat” prototypes to unfold business opportunities in the “NewSpace” era

The Business & Economy in Space Technology (BEST) programme, the first-of-its-kind Space Technology initiative in Hong Kong for secondary school students, has come to an end with roaring success.  "BEST" is a guided, STEM-based, hands-on and immersive, interdisciplinary educational experience with a strong entrepreneurial edge. It is based around a CubeSat concept & a design programme that has resulted in an astonishing level of quality and ideas from participating schools.   The programme was co-organised by the HKU Academy for the Talented1, the HKU Laboratory for Space Research2 and the Orion Astropreneur Space Academy (OASA)3, with an aim to nurture the next generation of  STEM “Astropreneur.”. Participants attended a two-semester series of educational talks and workshops with professional mentorship guidance to learn how Space Technology and Space Data can bring immense business opportunities in the "New Space”4 era.   A total of 22 school teams participated in the programme, including Carmel Pak U Secondary School, Shung Tak Catholic English College, Queen's College, St. Stephen’s Girl’s College, Victoria Shanghai Academy, and Chinese International School etc. The teams applied Space Technology to design a “CubeSat” that can tackle critical issues and imminent challenges under the United Nations’ 17 Sustainable Development Goals. Their projects yielded some exciting business opportunities in the “New Space” Era that can contribute to the future development of Hong Kong, the GBA and mankind.   “The judging panel for the final competition is comprised of industry professionals, including Mr Howard Cheng, the Chief Operating Officer of Cyberport, and Professor Quentin Parker, the Director of HKU Laboratory of Space Research. The “BEST Overall Award” was awarded to Victoria Shanghai Academy's project “QBE Agricultural Monitoring”. The team proposed the use of a remote sensing CubeSat as a real-time crop monitoring system for farmers that can expand production and maximise yields. One of the team members, Nicole Tse, said: “I got to explore Space Economy and gained hands-on experiences, and this really inspired me to consider studying related programmes in the future.” Team captain Michael Tong also said: “Our mentors guided us throughout our journey and were really helpful. They pointed out our blind spots and provided us with new perspectives, we have learnt a lot from this project.”   The “The BEST Astropreneurship Award” was won by St. Stephen's Girls' College. Its project “spASH” worked on a meaningful initiative that allows people to commemorate deceased loved ones in a special way. They proposed an affordable commemoration service by sending small samples of cremated ashes into earth orbit with a CubeSat. The in-orbit camera can send back pictures of earth, and the CubeSat also allows people to send commemorating messages to Space. Ms. Yau, a teacher from St. Stephen’s Girls’ College said: “Students can truly explore interdisciplinary STEM topics when choosing their project topic. In the process of building a CubeSat, students have to ensure that their final project is technically feasible and that their marketing plan could be carried out. It was truly an unforgettable STEM learning experience for the school team.”   The judging panel appreciated the ideas and designs of all the projects and praised the teams for coming up with innovative CubeSat concepts that are very innovative and even better than many similar competitions The teams put forward specific solutions targeting global issues, while at the same time taking into account the commercial and technical aspects of the project. The overall plans are comprehensive and feasible, and are comparable to the designs from students in tertiary institutions and start-up companies.   Professor Bennett Yim, Director of Undergraduate Admissions and International Student Exchange, said that he was delighted to see the outstanding performance of all teams. The global Space Economy is one of the main areas of development in today’s digitalized world. HKU hopes that through this programme, secondary school students can gain a deeper understanding of such cutting-edge scientific knowledge and technology, and join the new generation of Space Economy entrepreneurs.   Below are the details of the winning teams: Award Awarded Team Awarded Project The BEST Overall Award Victoria Shanghai Academy QBE Agricultural Monitoring While over one-quarter of the world’s agricultural land resides in Sub-Saharan Africa, only 5% of Sub-Saharan soil is currently being irrigated. In view of this, the team has proposed the use of a remote sensing CubeSat as a real-time crop monitoring system that can help expand production and maximise yields. The BEST Astropreneurship Award St. Stephen's Girls' College spASH The team aimed to provide an alternative commemoration method. Many samples of cremated ashes can orbit the Earth within a CubeSat to provide a novel service for loved ones. The BEST STEM Award Li Po Chun United World College of Hong Kong Seatellite By equipping CubeSat with calibrated infrared sensors, global oil spills can be accurately detected, providing a more economical and sustainable way to help manage oil spill pollution issues. The Most Liked Project Award Chinese International School Team 1 Soil Salinity The team simulated a CubeSat on board hyperspectral camera to provide Red, Green and Blue (RGB) image values that can be converted into a salinity index to indicate the amount of salt stress within the soil. The project targets underlying problems from the rapidly growing population that has been putting food security at risk.   Check out the winning school team videos from the BEST programme (5mins each): https://cubesat.hku.hk/school-teams   The Business & Economy in Space Technology (BEST) programme The Business & Economy in Space Technology (BEST) programme is supported by the HKU Academy for the Talented, the HKU Laboratory for Space Research and the Orion Astropreneur Space Academy (OASA). It is the first-of-its-kind Space Technology initiative in Hong Kong for secondary school students that is aimed at nurturing the next generation of “Astropreneur.” Participants attend workshops with professional mentorship guidance to learn how Space Technology and Space Data can bring immense business opportunities in the "New Space” era.   Professor Quentin Parker, Director of the HKU Laboratory for Space Research and the Business and STEM Mentors offer professional guidance to the St. Stephen's Girls' College team on their project “spASH". The school team from Li Po Chun United World College of Hong Kong provides a more economical and sustainable way to solve oil spill pollution issues by equipping CubeSat with infrared sensors that accurately detect the scope of oil spills.   Notes: 1The Academy for the Talented, established in 2011 at the University of Hong Kong, is a membership-based programme that brings together global students from diverse backgrounds. The unique programme challenges members to better understand their intellectual potential and advance their academic and personal development (talented.hku.hk). 2The HKU Laboratory for Space Research (LSR) is an interdisciplinary research entity that strives to play an important role in strategically positioning astrophysics, space, and planetary research of both HKU and Hong Kong SAR to a higher level (www.lsr.hku.hk). and to take advantage of the burgeoning global space and planetary science ecosystem. 3OASA, or The Orion Astropreneur Space Academy (Hong Kong) Limited, is an NGO that has been established to accelerate talents and start-ups for NewSpace opportunities throughout the world, starting from the international city of Hong Kong.  OASA works closely with all universities, mindful employers and help them establish STEAM programs where youths can learn how to build their own careers in the NewSpace era and improve ESG.  (www.oasahk.org). 4“NewSpace” is a term coined to refer to the recent commercialisation of the space sector.  

NEWS DETAIL

A Start-up Co-founded by Graduates from School of Biological Sciences was Funded by Innovation and Technology Commission (ITC) to Provide Testing Services for Food Products

Food production went through a long and complex manufacturing supply chain that could span continents and involve third-party vendors at each step of the way, giving rise to food fraud. The issue drained a huge amount of money from the food industry by substituting high-quality food with cheaper alternatives, often from unknown, unsecured sources. Making matters worse, substitutions are often undetectable in final products.  In view of this, PhD graduates Dr Colin Chung-Lim LUK(on the left) and Dr Inga Elizabeth CONTI-JERPE from School of Biological Sciences, co-founded a start-up business ‘isoFoodtrace’ to provide testing services for food products by using stable isotope technology, which helps detect food fraud and ensure food safety. In collaboration with the Stable Isotope Laboratory at School of Biological Sciences, its scientific testing service can trace food products’ origin and farming/rearing method (grass-fed, wild-caught, free-ranged or organic) with half the cost of existing services and require only a small amount (1 gram) of sample for each test.  This start-up business has been awarded HK$200,000 by Technology Start-up Support Scheme for Universities (TSSSU) 2022-2023 exercise under the Innovation and Technology Commission.  

NEWS DETAIL

HKU Science ‘Earth Day Lecture’ Series Imposing Public Awareness of Environmental Challenges

Destructive environmental change is already happening — acting now can reduce the risks of climate moving to ever greater extremes. Earth Day (April 22) is the day for us to remember the significance of protecting our planet Earth. To heed conservation calls and to raise awareness of environmental challenges on this particular day, the Faculty of Science of The University of Hong Kong (HKU) specially presented the ‘Earth Day Lecture’ series, hoping to bring new insights into both the academic arena and the general public through lectures delivered by our Distinguished Visiting Scholar and our own renowned environmental scientists, respectively. Professor Peng GONG, HKU Vice-President and Pro-Vice-Chancellor (Academic Development) expressed his gratitude to Professor John CHERRY of the University of Waterloo, as well as Dr David BAKER and Dr Alice HUGHES from HKU, for delivering these inspiring seminars. ‘HKU has a long tradition of excellent research on a wide range of issues related to our mother Earth. This Earth Day Lecture series marks a new level of recognition of Earth-related instruction and research by many Faculty members and students on campus. We will continue to organise such meaningful lectures to celebrate progress in science, technology, and governance toward reaching harmony between humans and nature,’ said Professor Gong. Environmental challenges associated with groundwater One of the dominant narratives in popular press accounting for the overriding crisis of climate change is no doubt anthropogenic greenhouse gas emissions. Still, scientists have been urgently reminding the community that groundwater is also immensely important to the well-being of humanity and ecosystems. Initiated by HKU Department of Earth Sciences, Distinguished Emeritus Professor John CHERRY from the University of Waterloo, also the leader of The Groundwater Project at the University of Guelph, was invited to share his views at the lecture ‘The Condition of the Planet and Humanity Concerning Freshwater and Food; A Groundwater Viewpoint’, elaborating how groundwater serves as an essential global commodity for food security, for human health and well-being, for sustaining environmental diversity, and for adaptation given the downward projections for humanity in the context of climate change. Professor Cherry suggested that we must acknowledge our inability to communicate the importance of groundwater. ‘The Planet is facing a freshwater crisis with groundwater at its heart. In some regions, aquifers supporting irrigation are going dry, causing rising food insecurity in the globalised economy. Elsewhere, two billion people live in water poverty desperately need more wells to extract water from under-utilised aquifers. Large global financial resources are now directed at reducing greenhouse gases with little directed at the water crisis to reduce immense human suffering, worsening as drought spreads and more than a billion people are added to the global population,’ said Professor Cherry. Dr Man Hoi LEE, Head of HKU Earth Sciences, thanked our distinguished speaker and said, ‘We are honoured to host Professor Cherry, who is widely recognised for his work in groundwater research, protection and management, for his lecture on a vital but often underappreciated component of the Earth's water cycle: groundwater, which contains 99% of the world's fresh liquid water.’ Data driven solutions for environmental challenges Science cannot stand alone. Bridging the gap between science and society helps in constructing the way for a sustainable future. The public seminars under ‘Data-driven Solutions for Environmental Challenges’ organised by HKU School of Biological Sciences, covered the topic beyond the scope of scientific research – how we bridge science with enterprise and how to utilise biodiversity data for developing effective conservation policy and management.  ‘Developing the most effective solutions relies on a holistic understanding of data gaps and the limits of the application of our knowledge so we can have confidence in our proposed solutions, and translate them into a context where they work within the bounds of society and can translate into real-world action,’ said one of the speakers Dr Alice HUGHES. ‘Earth Day is an opportune time to reflect on our collective impacts on nature. There is an old paradigm that economic development and conservation are mutually exclusive, and incompatible. Today, we are opening our eyes to a new future where conservation and sustainability are compatible, and profitable. To achieve this, we must face head-on the challenge of subverting greenwashing and that requires well trained scientists and engineers to provide solutions and careful accounting,’ another speaker Dr David BAKER added. In addition to the seminar series, this year we also launched an ‘Environmental Science Chalk Talk’, which served as a very interactive way to engage our undergraduate students to communicate science and discuss their potential career paths in environmental science and sustainability. The organiser Dr Caroline DINGLE commented that the Chalk Talks were designed to help students learn about the many different ways that scientific knowledge could be applied to tackle complex environmental problems. ‘Whether students pursue careers as practising environmental scientists, or whether they use scientific data to make evidence-based decisions in other fields, having a good understanding of the scientific process will help them to evaluate and apply scientific evidence in the future.’

NEWS DETAIL

HKU Biologists Find a New Protective Factor against Excessive Lipid Accumulation in the Liver of Obese Mouse Providing a Potential Treatment for Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD), commonly known as fatty liver disease, is a prevalent disease frequently seen in obese people. Having high fat content in the liver is detrimental as it is strongly associated with severe health problems like diabetes, high blood pressure, and liver cancer. A research team led by Dr Chi Bun CHAN, Assistant Professor from the School of Biological Sciences, Faculty of Science, The University of Hong Kong (HKU), uncovers a new protective mechanism against this disorder. The research findings have recently been published in the world-leading scientific journal Hepatology. Three keywords of the research: SBK1 protein - serves to control lipid accumulation in the liver. Nur77 - a well-established transcriptional factor in liver cells to control the expression of genes for lipid synthesis.  FGF21 - a metabolic hormone fibroblast growth factor 21 in the liver cell, which impairs the communication between the liver and other organs. The liver is the vital organ that orchestrates the overall glucose and fat metabolisms in the human body. Disruption of the fat metabolism in the liver will eventually result in hyperglycemia and hyperlipidemia, which are strong risk factors for developing diabetes, hyperlipidemia, and liver cancer. It is predicted that the number of NAFLD patient will increase from 80 million in 2015 to 100 million in 2030. While the outcomes of fat accumulation in the liver have been well established, it remains unclear if the liver possesses any defensive mechanism to work against the damage. To answer this question, Dr Chan’s team examined the expression of genes in the liver of high fat diet-induced obese mouse and found a protein, SH3 domain binding kinase (SBK1), was exclusively elevated in the obese mouse liver. SBK1 is a protein kinase first discovered in 2001, but no follow-up study has been performed to determine its functions in mammals. Hence, the functions of this novel protein remain unknown.  For the first time, Dr Chan’s team found that fatty acid accumulation is an inducer of SBK1 in the mouse liver. They also observed that the mice without the SBK1 gene in their liver, called ‘LSKO (liver-specific SBK1 knockout)’ mice, have higher lipid accumulation and fibrosis in this tissue. Moreover, the LSKO mice displayed uncontrolled hepatic glucose output and higher blood glucose level, and are less sensitive to insulin stimulation than their control cohort, which are strong indicators of diabetes development. In addition to the animal studies, Dr Chan’s team also utilised cultured cell models to answer how SBK1 gene controlled the lipid metabolism in the liver. They found that SBK1 phosphorylated and enhanced the activity of Nur77, a well-established transcriptional factor, in liver cells to control fatty acid uptake and lipid synthesis. When the SBK1 protein activity was abolished in the liver cells, they took up more fatty acids and developed excessive lipid accumulation that interfered the insulin signaling. Surprisingly, another metabolic hormone in the liver cells, fibroblast growth factor 21 (FGF21), was also reduced when the SBK1 protein was abolished in the cultured liver cells and the LSKO mice. Since FGF21 is an important hormone from the liver to communicate with other peripheral organs like white adipose tissues, the reduced FGF21 hormone production in the LSKO liver thus impairs the communication between the liver and other organs, leading to the development of insulin resistance in other tissues. To extend their findings to therapeutic application, the research team further tested if manipulating the SBK1 protein activity in the liver could rescue the damaging effect of obesity. Using adenovirus-mediated gene delivery, they transiently increased the amount of SBK1 protein in the mouse's liver with fructose diet-induced fatty liver disease and found pathological symptoms like liver steatosis, inflammation, etc. hyperlipidemia, and hyperglycemia were all alleviated.  ‘Our findings clearly show that SBK1 protein is an important regulator of the lipid metabolism that was neglected before,’ said Dr Chan. ‘We are very excited to see that increasing its activity effectively alleviates the health problems caused by fatty liver. But we still need more studies to fully depict its functional activity so that we can develop SBK1 activator as a new treatment agent for this common liver disease,’ Dr Chan further added. This work was supported by the Hong Kong Research Grant Council, the Health and Medical Research Fund, and HKU Seed Fund for Basic Research. The journal paper can be accessed from here. Key findings on the liver protective factor SBK1: Fatty acid accumulation will induce SBK1 protein in the mouse liver, which serves to control lipid accumulation and fibrosis in the liver. SBK1 protein phosphorylates and enhances the activity of Nur77, a well-established transcriptional factor, in liver cells to control the expression of genes for lipid synthesis.  If the activity of SBK1 is inhibited, the Nur77-controlled gene expression will be interfered, leading to more fatty acid uptake and lipid accumulation. Insufficient SBK1 protein decreases the production of a metabolic hormone fibroblast growth factor 21 (FGF21) in the liver cell, which impairs the communication between the liver and other organs, leading to the development of insulin resistance in other tissues. About the research team Led by Dr Chi Bun CHAN of the School of Biological Sciences, the project was conducted by a team of international scientists including: Dr Chi Wai LEE from School of Biomedical Sciences, Lee Ka Shing Faculty of Medicine, HKU; Dr Kenneth King Yip CHENG from the Department of Health Technology and Informatics, the Hong Kong Polytechnic University, Dr Leo Tsz On Lee of Faculty of Health Sciences, University of Macau, Professor Baowei JIAO of the Chinese Academy of Science Kunming Institute of Zoology and Dr Xiuying YANG of Institute of Materia Medica of Peking Union Medical College. Dr Palak AHUJA, Ms Xinyi BI, Dr. Chun Fai NG, Dr Wing Suen CHAN, Mr Brian Pak Sing PANG, Ms Miaojia HANG, Ms Elsie Chit Yu IU [School of Biological Sciences (SBS)], and Dr Margaret Chui Ling TSE [School of Biomedical Sciences (SBMS)] of HKU are the major contributors of the study. Click here for more information about Dr Chi Bun CHAN’s work and his research team. 

NEWS DETAIL

HKU Science excels in QS World University Rankings by Subject 2022

According to the QS World University Rankings by Subject 2022, HKU Science continues to excel in a wide array of science disciplines. The rankings symbolise the relentless effort of all Faculty members, and we will not be complacent but devote to achieve teaching and research excellence, creating knowledge and impacts.  Ranking summary: Biological Sciences: #62 Chemistry: #41 Earth & Marine Sciences: #51-100 Environmental Sciences: #31 Geology: #51-100 Life Sciences & Medicine: #49 Materials Science: #53 Mathematics: #56 Natural Sciences: #57 Physics & Astronomy: #67 Statistics & Operational Research #47

NEWS DETAIL

Research Assistant Professor Won 2021 International Organization of Chinese Physicists and Astronomers Outstanding Dissertation Award

Dr Wenyuan WANG, Research Assistant Professor at the Department of Physics, has recently been presented with the 2021 International Organization of Chinese Physicists and Astronomers (OCPA) Outstanding Dissertation Award for his outstanding contribution to the studies of a wide spectrum of quantum key distribution (QKD) protocols including the standard decoy-state BB84 protocol and the more recent measurement-device-independent (MDI)-QKD protocol and twin-field (TF)-QKD protocol. About Dr Wang and his Research Work Dr Wang received his BSc in Physics & Computer Science (double major) from The University of Hong Kong (HKU) in 2015, and PhD in Physics from the University of Toronto in 2020 under the supervision of Professor Hoi-Kwong LO. He worked at the University of Waterloo as a postdoctoral fellow for one year, and re-joined HKU in 2021 as a Research Assistant Professor collaborating with Professor Hoi-Kwong Lo. Dr Wang’s main research interest is quantum communication, especially the design and optimisation of quantum key distribution (QKD) protocols, quantum networks, as well as the combination of novel computational techniques (e.g. machine learning and semi-definite programming) with QKD. Having re-joined the Physics Department at his alma mater, Dr Wang hopes to contribute by addressing practical problems in quantum communication and pushing its boundaries, as well as bringing in new perspectives in the field by utilizing cross-disciplinary computational approaches. About the Outstanding Dissertation Award The International Organization of Chinese Physicists and Astronomers (OCPA) is a non-political, not-for-profit organisation aiming to promote physics and astronomy research in general and especially the achievements by ethnic Chinese physicists and astronomers. Its membership includes Nobel Laureates, a Field Medalist, members of the National Academy as well as many outstanding leaders of physics/astronomy research today. The Outstanding Dissertation Award is awarded each year by OCPA to PhD recipients of Chinese ethnicity who obtained their degree in the past two years. Candidates are nominated by their PhD supervisor, and up-to-four recipients world-wide are selected each year for the award by a committee of distinguished physicists and astronomers, in recognition of the significant contributions to the field made by the awardee during their PhD studies. For details of the award, please visit here.   

NEWS DETAIL

In Loving Memory of Professor Douglas Payne

It is with deep sadness that we mourn for the passing away of Professor Douglas PAYNE on March 6, 2022 at his advanced age of 97 in London. We honour the memory of Professor Payne in many aspects, be it his contributions for the Faculty development as the Dean of Science (1968-1974), or his relentless commitment in advancing the Department of Chemistry as our longest serving Head (1966-1982). Professor Payne’s passing is a great loss to the HKU community. As one of our most respected, beloved and influential teachers in the Faculty, he was loved by generations of students – the establishment of the Douglas Prizes in Chemistry for undergraduate students by his former students in early 1990s was the best proof for that. We believe the Prizes will have ongoing influence in the academic realm and Professor Payne’s spirit will continue to ignite our young bright students.  We honour the memory of Professor Payne for his dedication and contributions to both the Faculty of Science and Department of Chemistry. He will be dearly missed by all whose lives he touched, and we offer our deepest condolences to his family. 

NEWS DETAIL

New Uses of Old Drugs: Silver Nitrate with More Than 2,000 Years Antimicrobial History Can Re-sensitise the Last-line Antimicrobial Colistin in Combination Therapy against Superbugs

Drug-resistant superbugs pose a huge threat to human health. Currently, colistin is regarded as the last-line antimicrobial against extensively drug resistant (XDR) bacterial infections caused by pathogens, such as Salmonella, Pseudomonas aeruginosa, Klebsiella pneumoniae, Escherichia coli, Shigella and Acinetobacter baumannii. Unfortunately, the efficacy of colistin has been seriously compromised in the regular treatment of lethal bacterial infections, owing to the emergence of mobilized colistin resistance gene-1 (mcr-1) firstly identified in 2015. To cope with the serious challenge in the post-antibiotic era, scientists try to re-sensitise the resisted antibiotic against pathogens by using combination therapy between antibiotic and antibiotic- resistance breaker (ARB) to overcome antibiotics-resistance, which will open a window to treat these clinical infections caused by multidrug-resistant pathogens. A research team led by Professor Hongzhe SUN, Chair Professor from the Department of Chemistry, Faculty of Science, in collaboration with Dr Pak-Leung HO, Director of the HKU Carol Yu Centre for Infection from the Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong (HKU), discovered that an ancient antimicrobials drug, i.e., silver nitrate (AgNO3), can re-sensitise colistin against these multidrug resistant superbugs. Silver nitrate has a long antimicrobial history (more than 2,000 years) and is used to be applied in these external bacterial infections, such as skin infection. The ground-breaking findings on antimicrobial resistance (AMR) are now published in a leading multidisciplinary science journal Proceedings of the National Academy of Sciences of the United States of America (PNAS). The study is an extension of their past studies on antibiotics-resistance (Note 1). The research team previously discovered an anti-rheumatic agent, auranofin, as a dual-inhibitor to re-sensitise colistin and β-lactam antibiotics, of which the findings were published in Nature Communications in 2020. “Considering the well-recorded safety history of silver nitrate as ancient antimicrobial drugs applied in external infection, silver nitrate can work with auranofin to reinforce each another in treating the infections caused by mcr-positive multidrug resistant superbugs, which provides a new hope to overcome antibiotics-resistance crisis in the post-antibiotic era,” said Professor Sun.   Background Antimicrobial resistance (AMR) occurs when bacteria mutate or adjust in response to the misuse or overuse of antimicrobial. As a result, antimicrobial cannot kill bacteria or inhibit its growth any more. AMR has become one of the biggest public health challenges in this era. According to a report from World Health Organization (WHO), by 2021, the number of people worldwide suffering from antibiotics-resistance will be 9% more than the previous year. Indeed, it also predicted that the total number of people infected by multidrug resistant superbugs will up to tens of millions by 2050, which may even exceed the number of people suffering from cancer. Under the special situations of the current pandemic, antimicrobial resistance caused by improper use of antibiotics has a worsening trend. The Hong Kong’s Department of Health has pointed out that a study found that up to 71% of COVID-19 patients had received antibiotic treatment, and only 4% of them had bacterial infection (Note 2). Colistin, a polymyxin E family antimicrobial, is regarded as the last-line antimicrobial against extensively drug resistant (XDR) gram-negative bacteria infections. Unfortunately, scientists have first identified the emergence of mobilised colistin resistance gene-1 (mcr-1) in 2015, which has seriously compromised in the efficacy of colistin in regular treatment of lethal bacterial infections. Worse still, owing to the rapid evolution rate of mcr, other family members have also been identified, and each has its own sub-types. These plasmid-borne resistances can cross-spread rapidly via horizontal gene transfer between bacterial strains and species, resulting in emergence of multiple drug resistant superbugs. As said by Dr Tedros Adhanom Ghebreyesus, Director-General of WHO, “As we gather more evidence, we see more clearly and more worryingly how fast we are losing critically important antimicrobial medicines all over the world.” Thus, in clinical practice, common infections with these “superbugs” may soon be untreatable, which will severely endanger the public health system and leave patients with virtually no therapeutic options.   Key findings The research team found that silver (Ag+) including silver nanoparticles can restore colistin efficacy against mcr-positive bacteria. By using X-ray crystallography method (a X-ray to observe the distribution of electron density in crystal), they confirmed that silver inhibited the activity of MCR-1 enzyme via substitution of Zn2+ (a key factor to result in colistin resistance) in the active site as well as forming a tetra-silver cluster in the active-site pocket of MCR-1. The tetra-silver center effectively inhibits the activity of MCR-1 enzyme, leading to the dysfunction of MCR-1. The study further showed that silver effectively slows down the development of higher-level resistance and reduces mutation frequency. In the mouse-skin infection model, the combination therapy composed of AgNO3 and colistin is also highly effective in relieving the dermonecrotic lesions and reducing the bacterial load. In conclusion, the great combination effect in vitro and in vivo undoubtedly offers a promising strategy to overcome antimicrobial resistance in post-antibiotic era.   About the research team The research was conducted by a team led by Professor Hongzhe SUN, Norman & Cecilia Yip Professor in Bioinorganic Chemistry, The University of Hong Kong. Drs. Qi ZHANG and Runming WANG from the same affiliation are co-first authors. Other HKU scientists contributing to the research included Dr Chunjiao LIU, Postdoctoral fellow (Department of Microbiology, Li Ka Shing Faculty of Medicine), Dr Mohamad Koohi-Moghadam, Research Assistant Professor (Faculty of Dentistry), Dr Haibo WANG, Postdoctoral fellow (Department of Chemistry, Faculty of Science), Dr Pak-Leung HO, Director of the HKU Carol Yu Centre for Infection (Department of Microbiology, Li Ka Shing Faculty of Medicine ), and Dr Hongyan LI, Research Assistant Professor (Department of Chemistry and State Key Laboratory of Synthetic Chemistry, Faculty of Science). Dr Minji WANG, Associate Professor from Department of Chemistry and Molecular Engineering, East China Normal University, has also contributed a lot. The work was supported by Research Grants Council of Hong Kong, Health and Medical Research Fund and Seed Fund for Basic Research and The University of Hong Kong.   About Professor Hongzhe SUN Professor Hongzhe SUN is a Norman & Cecilia Yip Professor in Bioinorganic Chemistry and Chair Professor in the Department of Chemistry at The University of Hong Kong. His research focuses on metalloproteins, medicine chemistry (discovery of antimicrobial agents), and inorganic chemical biology. Professor Sun has published a series of well-recognized work in overcoming antimicrobial resistance against superbugs, developing anti-coronavirus agent, and understanding the functions of metalloproteins. More information about Professor Hongzhe SUN and his research group can be found in their group's webpage: https://www.bioinorg-chem.hku.hk   About the research paper: https://www.pnas.org/doi/full/10.1073/pnas.2119417119   Note 1: (Press Release) HKU scientists reveal an anti-rheumatic metallodrug can resurrect “last- resort” antibiotics to kill multi-drug resistant superbugs https://www.scifac.hku.hk/press/release/press-release-antirheumatic-metallodrug Note 2: Antimicrobial Resistance - Frequently Asked Questions hhttps://www.chp.gov.hk/files/pdf/amr_faqs_eng.pdf (Source: Centre for Health Protection, Department of Health)   Captions for the images:  Cartoon of active-site pocket of MCR-1-S enzyme with cofactor Zn2+ shown as the blue sphere (upper left) and the novel tetra-nuclear silver center in the active-site pocket of Ag-MCR-1-S (upper right). Ag+ shown as wheat spheres are bridged in a narrow pocket by either coordination bonds (red solid lines) or hydrogen bond (red dash line).The substitution of Zn2+ from MCR-1-S by Ag+ and inhibition of substrate (phosphorylethanolamine, pEtN) bound to MCR-1-S enzyme result in the loss of enzyme activity, which is reflected by the recovered membrane potential (middle right). Growth curves of MCR-1-J53, a pathogen carrying mcr-1 gene, treated with different drugs in vitro (lower right) and bacterial load in abscess area on day 7 in the skin of Balb/c mice infected with mcr-1 positive K. pneumoniae 9607 and received single dose of vehicle, mono-therapy of colistin, AgNO3, or their combination (i.e. AgNO3+colistin) (middle left). Resistance acquisition curves of MCR-1-J53 during 16 passages with the sub-inhibitory concentrations of colistin alone or combination of colistin and AgNO3 (lower left). The inset shows the normalized expression level of MCR-1 in MCR-1-J53 receiving different treatments.

NEWS DETAIL

The First Edge Computing AI Chip in Hong Kong for Real-time Video Analytics in Child Protection and Patient/Elderly Risks Monitoring during Omicron Outbreak

The society recently raised extra concerns about child safety after the alleged abuse and neglect reporting incidents at a children’s caring home, demanding better monitoring and enforcement of the law. Meanwhile, the Omicron outbreak also placed a heavy burden on public health care and isolation facilities, where we saw a surge of infection cases. Video monitoring appears to be an alternative to ease the shortage of healthcare staff at both clinical and elderly facilities during the pandemic situation. Nevertheless, security and privacy are some concerns of video monitoring that have to be resolved. In light of this, the Data Science Lab at Department of Statistics and Actuarial Science (SAAS), The University of Hong Kong (HKU) has developed several real-time video analytics apps using the first Hong Kong-made edge computing AI chip donated by Marvel Digital AI Limited, making it able to detect human body’s movements (e.g. walking, falling, leaving room, etc.) and facial expression (e.g. crying, yelling, etc.).  Fire alarming detection and door open detection.    Applying the techniques of bounding box detection, object detection, and motion classification, the team built the app with “ResNet-32”, a Deep Learning Neural Network specified in image recognition, and “Flasks”, the framework of programming language Python, for video analysis, and used over 5,000 images on average collected from Internet to train each model. Densifying the data centre network, the edge computing AI chip allows faster computing, better data security, and efficient control over the continuous operation – it is ten times faster than the market edge-based AI chip in terms of computation power. Since the video analysis are done in the AI chip itself, it does not require running the apps in a cloud computing platform, thus overcoming the security and privacy concerns of video transmission on the Internet. In addition, the AI chip can be implemented in any device such as robotic pet, surveillance camera, etc.  It can be used in the homecare/childcare/elderly care centres, offices, shopping malls, or hotels for risk detection and personal care monitoring. In the case of child abuse at children’s caring home, the video analytics apps can be deployed for childcare monitoring. Also, the apps can assist nurses in monitoring patient risks in isolation wards, alerting them if patients leave the ward, asking for helping or deliberately self-extubate their endotracheal tubes, and helping elderly homes to detect elderly care risks such as falling and yelling for help, etc. Baby’s movement detection: walking & crawling   “It is the first edge computing AI chip developed by our company in Hong Kong.  Thanks to Data Science Lab for deploying our newly invented AI chip with their real-time novel video analytics apps that overcome the security and privacy concerns on video analytics and surveillance,” said Dr Patrick MA, CEO of Marvel Digital AI Limited. Other than security and safety monitoring, the AI chip can also be used in processing and analysing big data in finance and medicine, for investment and disease diagnosis decision-making, virtual reality, robot automation, smart home, physical and cognitive training, drug and gene discover. “Data Science Lab is currently researching on a novel parallel and distributed AI algorithm and is planning to deploy it in an environment of clustered edge computing AI chips. In this way, a real-time big data analytics with a supercomputing power can be done and is a breakthrough in AI development,” said Dr Adela LAU, Deputy Director of the HKU SAAS Data Science Lab.   About HKU SAAS Data Science Lab The project team of Data Science Lab at HKU comprises Head of Department of Statistics and Actuarial Science (SAAS) Professor Guosheng YIN, Director of the SAAS Data Science Lab Dr Eddy LAM, Deputy Director Dr Adela LAU, as well as undergraduate and taught postgraduate students in the Department. From left to right: Dr Patrick MA (CEO of Marvel Digital AI Limited), Professor Guosheng YIN (HKU Head of Department of Statistics and Actuarial Science), Dr Herbert LEE (Chairman of Marvel Digital AI Limited) and Dr Adela LAU (Deputy Director of SAAS Data Science Lab An overview of system design for the real-time Edge Computing AI Chip.    The Edge Computing AI Chip (with desktop machine) developed by Marvel Digital AI Limited.

NEWS DETAIL

Distinguished Chemist Professor Vivian Wing-Wah YAM Elected as next President of The International Organization for Chemical Sciences in Development (IOCD)

NEWS DETAIL

Rapid evolution fuels transcriptional plasticity in fish species to cope with ocean acidification

A research team led by Dr Celia SCHUNTER at School of Biological Sciences (area of Ecology and Biodiversity) & The Swire Institute of Marine Science, The University of Hong Kong (HKU), in collaboration with researchers from The University of Adelaide, James Cook University in Australia, IRD Institute in New Caledonia, and Okinawa Institute of Science and Technology Graduate University in Japan, revealed the basis to variability across different fish species and uncovered that some species evolve more rapidly, providing them with evolved molecular toolkits and allowing them able to cope with future ocean acidification. The journal paper was recently published in Global Change Biology. Global ocean surface pH is projected to decline with the ongoing uptake of anthropogenic atmospheric CO2 by the oceans, a process termed ocean acidification (OA). A decade of laboratory experiments indicate that predicted OA conditions affect some marine fishes’ physiological performance, growth, survival, and crucial behaviours for the survival of the fish. To test how marine life will respond and whether adaptation to this rapid acidification is possible, researchers went to a remote place on this planet to study in situ exposure to elevated partial pressure of carbon dioxide (pCO2, the amount of carbon dioxide dissolved in water) and be able to predict how in the wild fish can cope with these environmental conditions predicted to exist across the globe by the end of this century. With rapidly changing environments due to human activities, it is crucial to be able to predict what will happen to marine organisms and in particular fish populations to optimise our conservation and management efforts. The study here indicated some fish species that evolve more rapidly may have a flexible way to cope with OA, which should be helpful for these species to maintain their population size and biodiversity. However, for some other species evolving slowly, OA will be difficult for them once the OA level is beyond their tolerance levels. Natural laboratories with elevated pCO2    Volcanic CO2 seeps can be used as natural laboratories where CO2 rises from the substratum and acidifies the surrounding seawater to levels similar to, or sometimes beyond, the projections for ocean acidification by the end of this century. Six adult coral reef fish species including damselfishes and a cardinalfish species from a reef within the Upa-Upasina CO2 seep in Papua New Guinea (pH 7.77, pCO2 846 µatm) and an adjacent reef (500 m distance) with ambient pCO2 (pH 8.01, pCO2 443 µatm) were sampled, tissues were extracted, analysed and sequenced for their cellular response to elevated CO2 in their brains. The six fish species in this study are common coral reef fish but exhibit slightly different ecologies including differences in parental care and being active during the day or night, and therefore we can, to a certain extent, extrapolate the found patterns also to other fishes. Common responses to OA across species Elevated pCO2 induced common molecular responses related to circadian rhythm as well as the immune system several of the species, revealing that these are important processes that are affected by elevated CO2 for many species. Circadian rhythms are the drivers of our 24-h biological clocks and exist in human, other animals and plants. They drive our sleep patterns and also our metabolism, and this shows that the circadian rhythm core genes affect many other downstream functions and can also affect behaviour. The adjustment here of the Circadian genes with elevated CO2 seemed to drive gene expression changes of other genes in the brain, which may allow the fish to flexibly react to the CO2. Immune regulation appears to further be an important function involved in the response to elevated pCO2. Interestingly, while this was the case across numerous species of reef fish, the nocturnal species exhibited an elevation in immune genes, whereas other species supressed the immune genes with elevated CO2. This is a phenomenon not previously studies and hint to the fact that nocturnal and diurnal species may respond differently and this warrant further study. A fish species possessing evolved molecular toolkits to cope with future OA The spiny damselfish, A. polyacanthus, can regulate the pH levels within its cells through the gene expression changes to respond the environmental elevated pCO2 at the CO2 seep. We originally thought that an elevation in the pCO2 to end-of-century predictions would not be a large impact to fishes, as they know how to regulate the pH, however we see that these coral fish species induced significant expression changes in many genes, especially A. polyacanthus, hence showing the need to regulate the cells in the brain in response to the CO2 levels in the ocean waters. For a brain to function properly and signalling to occur in the brain, providing the different neurons with essential information, ions such as calcium, sodium, potassium and chloride need to be transported. Here we found that such transporter genes changed their expression, especially for A. polyacanthus when living in the seeps, which shows that neural signal transductions needs to be altered in response to elevated CO2. Interestingly, during our sample collection at the remote reef a storm arose for 24 hours, which moved a lot of water of the CO2 seep site and increased the pH temporarily. We were able to collect some spiny damselfish during this time and now see that all the cellular changes are reversible as they changed quickly back to the levels of what we see at the control reef with current day CO2 levels. These results indicated A. polyacanthus may be able to switch their gene expression to respond rapidly changing pH levels. The spiny damselfish species, A. polyacanthus, evolve more rapidly than the other species over the past 15 million years, which leaves this species with an enhanced potential to adapt to changing environmental conditions. In particular, the genes seen to be important in the response to living in elevated pCO2, such as genes involved in intracellular pH regulation, circadian rhythm (can adjust the expression of many other genes), and ion transport (have impact on the neural signal transduction), also indicated an increased evolutionary rate. This can lead to increased gene expression alteration accordingly to environmental change namely transcriptional plasticity — to ocean acidification in A. polyacanthus. As such, this species may possess evolved molecular toolkits to cope with future ocean acidification. “It has been quite puzzling why some species struggle more than others with ocean acidification conditions. Our expedition to this remote CO2 vent site allowed us to look at many fish species that live naturally in these elevated CO2 conditions and complete parts of the puzzle,” Dr Celia Schunter remarked, “we see that possibly limited by slow evolution, some fish species may not be flexible when responding to elevated CO2 conditions and struggle more.” “Species that evolve more rapidly may have a flexible way to cope with ocean acidification, which should be helpful for these species to maintain their population size and biodiversity. However, for some other species evolving more slowly, ocean acidification will be difficult for them once the pH level beyond their abilities to maintain their acid-base balance. Previously we did not understand why some species struggled and others didn’t as much and understanding why some may be ‘winners’ or ‘losers’ is important so we can protect especially the ones that will not be able to cope and to keep the balance in the ecosystem,” added Dr Schunter. This study uncovered that some wild fish species may be equipped with inherent molecular tools via rapid evolution to cope with elevated pCO2 predicted to occur by the end of this century. The next goal for the research team is to validate if other ecosystems exhibit the same findings. Meanwhile, ocean acidification still is a threat for the fish species evolving slowly once the level of ocean acidification rises beyond their regulation ability. As such, slowing the decreasing global pH is key to maintaining high biodiversity of fish. The journal paper can be accessed from here.      

NEWS DETAIL

Reconstructing How Dinosaurs Fed and Grew

  Fion Wai Sum MA 2019 - present PhD candidate in Earth Sciences (Palaeobiology), University of Birmingham 2017 - 2018 Master by Research in Palaeontology and Geobiology, The University of Edinburgh 2013 - 2017 Bachelor of Science, double major in Geology and Ecology & Biodiversity, HKU   Vertebrate palaeontology research   Vertebrate palaeontology is more than digging up and describing bones, but the study of total biodiversity and transitions in the history of life.   More than 99% of the species ever lived on Earth are extinct. However, these extinct organisms are exceedingly important to our understanding of the total biodiversity and transitions in the history of life. As a researcher in vertebrate palaeontology, Fion Wai Sum MA uses fossil record to study evolutionary processes in vertebrate history. Non-avian dinosaurs are ideal models for studying macroevolutionary changes. They dominated the global terrestrial ecosystems for over 150 million years before they went extinct ~66 million years ago. One of Fion’s major lines of research is the dietary evolution of vertebrate animals. In a recent study, she used digital modelling and biomechanical analysis to study the feeding mechanics of theropod dinosaurs. Theropods are a group of dinosaurs that started off as carnivores and underwent significant dietary changes ¾ from carnivory to more specialised carnivory and herbivory. The team compared the feeding adaptations of carnivores and herbivores, and revealed that the jaws of all study groups became structurally stronger as they evolved through time.   Baby Yingliang measures 10.6 in (27 cm) long from head to tail and rests inside a 6.7 inch-long egg at the Yingliang Stone Nature History Museum in China.   Dinosaur embryo was about to hatch! Recently Fion co-led an international team to study the oviraptorosaur ‘Baby Yingliang’ ¾ one of the best-preserved dinosaur embryos ever discovered. Oviraptorosaurs are theropod dinosaurs closely related to birds and thus are instrumental in tracing the origin of modern avian features. The team suggested that the bird-like posture of ‘Baby Yingliang’ may indicate a similar prehatching behaviour in oviraptorosaur and modern bird embryos, and that the avian tucking behaviour could have originated among dinosaurs. Again, this shows that the features previously thought unique to modern birds, could have first evolved among their dinosaurian ancestors.   Fion applied digital modelling and functional analysis to study the feeding mechanics of theropod dinosaurs. Credit: Gabriel Ugueto. With her background in CT-scan-based imaging and 3D reconstruction, Fion has been collaborating with pterosaur specialists to study the fossils from northeastern China. In 2021, the international team named two new species of pterosaurs from the Jurassic, namely Sinomacrops bondei and Kunpengopterus antipollicatus. The latter, dubbed ‘Monkeydactyl’, represents the oldest record of an opposed thumb in the Earth’s history.   Hong Kong-born palaeontologist ‘hatched’ from HKU Science   During her time as an undergraduate at HKU, Fion was supported by a Summer Research Fellowship and an Overseas Research Fellowship to gain her first research experience. For two summers, Fion was under the supervision of palaeontologist Dr Michael PITTMAN.  She conducted research locally and at the Institute of Vertebrate Paleontology and Paleoanthropology (IVPP), Chinese Academy of Sciences. ‘I still remember how excited I was when I first entered the IVPP in Beijing. There were so many dinosaur fossils in the storage and I was delighted to be given the chance to study some of them,’ she said. With growing interest in this field, Fion decided to pursue postgraduate study and work towards becoming a vertebrate palaeontologist. After PhD graduation, Fion would like to continue her research career and use new techniques to further explore topics on vertebrate dietary evolution and dinosaur growth. ‘Vertebrate palaeontology is more than digging up and describing bones. This field is rapidly changing and increasingly interdisciplinary. As a palaeontologist, I need to keep track of the latest development in palaeontology, as well as the technological advances in other fields such as ecology, engineering and medical and veterinary sciences.’ By applying complementary techniques, Fion hopes to address palaeontological questions from new perspectives and contribute to our understanding of the history of life. Regarding the future plan, she admits palaeontology is an uncommon subject area with limited career opportunities in academia. ‘Sometimes I do feel uncertain about my career path, but I try to be open to possibilities, be proactive and equip myself for any arising opportunities,’ she added. As a Hong Kong-born palaeontologist, Fion hopes to come back to Hong Kong for research development if there is an opportunity. ‘Hong Kong would serve as a great base station for my research because East Asia is home to many vertebrate fossils, especially dinosaurs, and I have ongoing collaborations with several institutions in China,’ she said. The diversity of local universities provides a good platform for intra- and inter-institutional, cross-disciplinary collaboration. The high connectivity of Hong Kong with the other parts of the world also facilitates overseas fieldwork and museum visits. Although no dinosaur fossils are known, Fion wishes to study the fossils of Hong Kong alongside her research on vertebrate palaeontology. ‘I hope to study local palaeontology and stratigraphy by conducting fieldwork. Hong Kong has a geological history of over 400 million years with diverse fossils, including vertebrates, invertebrates, plants and microfossils. And I would like to contribute to enriching it,’ she added.  Video interview with BBC news

NEWS DETAIL

Scientists awarded Environmental and Conservation Fund to explore green solutions

Striving for green solutions has always been a core research focus among scientists. In the latest announcement of the Environmental and Conservation Fund (ECF) of the HKSAR Government, the Faculty of Science has secured HK$5.4million under the funding scheme “Environmental Research, Technology Demonstration and Conference Project 2021”, paving ways for our researchers to explore effective means to protect the environment and natural resources. A summary of the approved fund is appended below:   Project Coordinator Department/ School Project Title Approved Fund Project Duration Dr Louise Amy ASHTON Biological Sciences Establishing the Diversity and Status of Hong Kong’s Wasps HK$1,526,040 36 months Professor Aleksandra DJURIŠIĆ  Physics Photocatalytic Degradation of Microplastics HK$1,526,040 24 months Professor Zheng Xiao GUO Chemistry Clean Photocatalytic Re-solutioning of Precious Elements from eWaste and Re-use as Single-Atom Catalysts HK$1,281,360 36 months Dr Simon Yung Wa SIN Biological Sciences Assessment of the Population Status of the Endangered Hong Kong Cascade Frog (Amolops Hongkongensis) HK$794,080 30 months Dr Ho Yu AU YEUNG Chemistry Photoluminescent Carbon Dots Converted from Biomass for VOCs Sensing HK$498,000 30 months  

NEWS DETAIL

HKU Earth Scientists simulated the future: restored forests in the tropics survive climate change, prioritisation and targeting is the key to success

Replanting previously forested landscapes in the tropics is a nature-based solution that can play a role in removing carbon dioxide from the atmosphere, but whether those new forests will withstand the impacts of future climate change was a big uncertainty. There is reason to be hopeful that tropical forests restored today will survive until the end of the century, earth scientists from Department of Earth Sciences, The University of Hong Kong concluded in a new study published in Nature Climate Change. Solutions to combat global warming require reductions in human-caused emissions of carbon dioxide and other greenhouse gases. But in most cases, we also need to take active steps to remove excess CO2 from the atmosphere. Restoration of previously deforested landscapes may be one of the cheapest and most reliable ways of removing CO2 and safely storing it for centuries as the carbon is incorporated into wood and soils. Over the next decade, large investments are likely be made in forest restoration projects. To plan these projects it is crucial to know if the carbon stored in restored forests will be preserved when subjected to future climate change. Heat, drought, and wildfires all influence how tropical forests will fare in the future. By performing hundreds of computer simulations with a dynamic global vegetation model driven by a range of future climate scenarios and ecophysiological responses to CO2 concentrations,  the researchers found that carbon accumulated in regrowing tropical forests will remain in these forests even under the most severe future climate change scenarios. The researchers further examined hypothetical scenarios where only half of the available land is restored and sites are selected either by lowest cost of land, or the potential to accumulate the most carbon, or both. “Unsurprisingly selecting the cheapest available land results in the lowest carbon drawdown but climate change widens the gap between the scenarios even further,” says Dr Alexander KOCH, who conducted the simulations while a postdoctoral fellow in the Department of Earth Sciences. Restoring all potential tropical forest areas is likely not feasible for multiple reasons, hence prioritisation of forest restoration is needed. Using simulations of forests under future climate change also helps to point to places where climate change impacts are less severe and better suited for concentrating replanting efforts. “Our computer simulations demonstrate that in many parts of the tropics including the natural areas of Hong Kong and southern China, restoring degraded landscapes is worth it because these new forests will continue to accumulate carbon until the end of the century,” says Dr Jed KAPLAN, co-author and Associate Professor in the Department of Earth Sciences and the Institute for Climate and Carbon Neutrality at HKU. The authors note that even in Hong Kong, many protected areas contain landscapes that are suitable for forest restoration, for example in Lam Tsuen, Pat Sin Leng, and Lantau South Country Parks. “Large-scale tree planting won’t be enough to avoid climate disaster, but it can play a role. And if done with biodiversity and the people who call these forests a home in mind, forest restoration can have multiple benefits,” Dr Koch emphasizes. He adds, “So far we have only been able to look at carbon, but other aspects such as biodiversity in restored forests is also impacted by climate change. Assessing those impacts will be the next step.” Research on the impacts of climate change on biodiversity and ecosystem services in tropical forests is currently underway in HKU’s Faculty of Science. The journal paper can be accessed from here  

NEWS DETAIL

HKU physicists make a stride closer in the quest for quantum materials through better measurement of quantum entanglement

A research team from the Department of Physics, the University of Hong Kong (HKU) has developed a new algorithm to measure entanglement entropy, advancing the exploration of more comprehensive laws in quantum mechanics, a move closer towards actualisation of application of quantum materials. This pivotal research work has recently been published in one of the most prestigious journals in physics – Physical Review Letters. Quantum materials play a vital role in propelling human advancement. The search for more novel quantum materials with exceptional properties has been pressing among the scientific and technology community. 2D Moire materials such as twisted bilayer graphene are having a far-reaching role in the research of novel quantum states such as superconductivity which suffers no electronic resistance. They also play a role in the development of “quantum computers” that vastly outperforming the best supercomputers in existence. But materials can only arrive at “quantum state” , i.e. when thermal effects can no longer hinder quantum fluctuations which trigger the quantum phase transitions between different quantum states or quantum phases, at extremely low temperatures (near Absolute Zero, -273.15°C) or under exceptional high pressure. Experiments testing when and how atoms and subatomic particles of different substances “communicate and interact with each other freely through entanglement” in quantum state are therefore prohibitively costly and difficult to execute. The study is further complicated by the failure of classical LGW (Landau, Ginzburg, Wilson) framework to describe certain quantum phase transitions, dubbed Deconfined Quantum Critical Points (DQCP). The question then arises whether DQCP realistic lattice models can be found to resolve the inconsistencies between DQCP and QCP. Dedicated exploration of the topic produces copious numerical and theoretical works with conflicting results, and a solution remains elusive. Mr Jiarui ZHAO, Dr Zheng YAN, and Dr Zi Yang MENG from the Department of Physics, HKU successfully made a momentous step towards resolving the issue through the study of quantum entanglement, which marks the fundamental difference between quantum and classical physics. The research team developed a new and more efficient quantum algorithm of the Monte Carlo techniques adopted by scientists to measure the Renyi entanglement entropy of objects. With this new tool, they measured the Rényi entanglement entropy at the DQCP and found the scaling behaviour of the entropy, i.e. how the entropy changes with the system sizes, is in sharp contrast with the description of conventional LGW types of phase transitions. “Our findings helped confirm a revolutionised understanding of phase transition theory by denying the possibility of a singular theory describing DQCP. The questions raised by our work will contribute to further breakthroughs in the search for a comprehensive understanding of unchartered territory,” said Dr Zheng Yan.  “The finding has changed our understanding of the traditional phase transition theory and raises many intriguing questions about deconfined quantum criticality. This new tool developed by us will hopefully help the process of unlocking the enigma of quantum phase transitions that has perplexed the scientific community for two decades,” said Mr Zhao Jiarui, a PhD who came up with the final fixes of the algorithm. “This discovery will lead to a more general characterisation of the critical behaviour of novel quantum materials, and is a move closer towards actualisation of application of quantum materials which play a vital role in propelling human advancement.” Dr Meng Zi Yang remarked. Quantum entanglement entropy and quantum materials  A quantum system with subsystem A and its compliment B. For a quantum state, particles in subsystem A are entangled with particles in subsystem B through quantum entanglement. The quantum entanglement entropy is to measure how much particles in a subsystem A are entangled with the rest of particles in the system. Quantum entanglement is a universal feature for quantum materials and thus can be regarded as a fingerprint for various of quantum materials. The models To test the efficiency and superior power of the algorithm and demonstrate the distinct difference between the entanglement entropy of normal QCP between DQCP, the research team chose two representative models —the J1-J2 model hosting normal O(3) QCP and the J-Q3 model hosting DQCP, as shown in Image 2. The two lattice models: (a) For J-Q3 model, the Q term characterises the strength of the six-site plaquette correlation (pink-shaded area), and the J term characterises the strength of nearest neighbour correlation. (b) For J1-J2 model, J1 and J2 separately identify the correlation strength between two kinds of nearest neighbours. , The J-Q3 model hosts a DQCP when adjusting the ratio of Q term and J term, and the J1-J2 model hosts a O (3) QCP as the ratio of J1 and J2 is appropriately tuned.   Nonequilibrium increment algorithm Based on previous methods, the research team created a highly paralleled increment algorithm. As illustrated in Image 3, to the main idea of the algorithm is to divide the whole simulation task into many smaller tasks and uses massive CPUs to parallelly execute the smaller tasks thus greatly decreasing the simulation time. This improved method helped the team to simulate the two models previously mentions with high efficiency and better data quality. The schematic diagram of the QMC diagram and the nonequilibrium increment method.   Findings With the nonequilibrium increment method, the research team successfully obtain the second Rényi entanglement entropy SA2 at QCP and DQCP of the two models for different system sizes. The data is shown in Image 4, and one can find from the insets that when deducting the leading term(area law contribution from the entanglement boundary) the signs of the sub-leading term clearly distinguish the QCP (negative in J1-J2 model,) and DQCP (positive in J-Q3 model). This finding rules out the possibility of  the description of DQCP based on a unitary assumption and raises several intriguing questions about the theory of DQC. This discovery is likely to lead to a more general characterisation of the critical behaviour of novel quantum materials. Second Rényi entanglement entropy SA2 for (a) J1-J2 antiferromagnetic columnar dimer model at QCP and (b) J-Q3 model which hosts DQCP. The insets of (a) (b) show the subleading log-corrections acquires a opposite sign for the two cases.   About the research Mr Jiarui ZHAO is the first author of the journal paper. He is a PhD student from the Department of Physics, HKU, under the supervision of Dr Zi Yang Meng. The work was supported by the Research Grants Council of HKSAR, the Areas of Excellence “2D Materials Research: Fundamentals Towards Emerging Technologies”, the Seed Funding Quantum-Inspired explainable-AI at the HKU-TCL Joint Research Centre for Artificial Intelligence. We thank the Computational Initiative at the Faculty of Science and the Information Technology Services at HKU, and the National Supercomputer Centres in China for their technical support and for providing generous HPC resources that have contributed to the research results reported within this paper. The journal paper can be accessed from here.         

NEWS DETAIL

An HKU biologist-led team of international plant scientists reveals how guard cell chloroplasts obtain energy

Whether Guard Cells (GCs) carry out photosynthesis has been debated for decades. Earlier studies suggested that guard cell chloroplasts (GCCs) cannot fix CO2 but later studies argued otherwise. Until recently, it has remained controversial whether GCCs and/or GC photosynthesis play a direct role in stomatal movements. Dr Boon Leong LIM, Associate Professor of the School of Biological Sciences of the University of Hong Kong (HKU), in collaboration with Dr Diana SANTELIA from ETH Zürich, discovered GCs’ genuine source of fuel and untangled the mystery. The findings were recently published in prestigious journal Nature Communications. The paper was selected as a Featured Article by the journal’s editor. In the morning, sunlight triggers stomata, which are tiny pores on plant leaves, to open. This let CO2 in and O2 out to boost photosynthesis. The opening of stomata consumes a large amount of adenosine triphosphate (ATP), the cellular energy currency, but the sources of ATP for stomata opening remained obscure. Some studies suggested that GCCs carry out photosynthesis and export ATP to the cytosol to energise stomata opening. In mesophyll chloroplasts, ATP and NADPH (nicotinamide-adenine dinucleotide phosphate) are generated from photosystems, which are used as fuel for fixing CO2. By employing in planta fluorescence protein sensors, the team of Dr Boon Leong Lim at HKU was able to visualise real-time production of ATP (Note 1) and NADPH (Note 2) in the mesophyll cell chloroplasts (MCCs) of a model plant, Arabidopsis thaliana. “However, we could not detect any ATP or NADPH production in GCCs during illumination. Puzzled by this unexpected observation, we contacted an expert in guard cell metabolism, Dr Diana Santelia from ETH Zürich, for a collaboration,” Dr Lim said. Over the past decade, the Santelia lab provided deep and important insights into starch and sugar metabolism in the guard cells (GCs) surrounding the stomatal pores on the leaf surface.   Model of the coordination of stomatal function with starch and malate metabolism in guard cells.   In joint efforts, the team shows that unlike mesophyll cells (MCs), GC photosynthesis is poorly active. Sugars synthesised and supplied by MCs are imported into GCs and consumed by mitochondria to generate ATP for stomatal opening. Unlike MCCs (Note 1), GCCs take up cytosolic ATP via the nucleotide transporters (NTTs) on chloroplast membrane to energise starch synthesis in daytime. At dawn, while MCs start to synthesise starch and export sucrose, GCs degrade starch into sugars to supply energy and increase turgor pressure for stomatal opening. Hence, the function of GCCs to serve as a store of starch is important for stomatal opening. While MCs fix CO2 in chloroplasts via the Calvin–Benson–Bassham (CBB) cycle, CO2 fixation in the cytosol is the main pathway of CO2 assimilation in GCs, where the downstream product malate, is also an important solute to increase turgor pressure for stomatal opening. In conclusion, GCs behave more like a sink (receive sugars) than a source (provide sugars) tissue. Their function is tightly correlated with that of MCs to efficiently coordinate CO2 uptake via stomata and CO2 fixation in MCs. “I was very excited when Dr Lim contacted me asking to collaborate on this project,” Dr Diana Santelia said. “We have been trying to clarify these fundamental questions using molecular genetics approaches. Combining our respective expertise has been a winning strategy,” she continued. Dr Sheyli LIM, the first author of the article and a former PhD student of Lim’s group remarked: “The in planta fluorescence protein sensors we developed are powerful tools in visualising dynamic changes of the concentrations of energy molecules in individual plant cells and organelles, which allow us to solve some key questions in plant bioenergetics. I am happy to publish our discoveries in two manuscripts in Nature Communications using this novel technology”. Note 1: past press release on how chloroplasts maintain energy efficiency (Oct 2018) Note 2: past press release on energy flow in photosynthetic plant cells (Jun 2020)  The research paper can be accessed here.   Chinese version 中文版本 Media highlights in Chinese - TOPick 港大研究揭保衛細胞助植物儲糖及澱粉兼協調二氧化碳吸收和固定      

NEWS DETAIL

The AI Robotics Vision and Automation Technology Challenges Competition 2021 identified talented students in the area of statistics, AI, and data science

The Data Science Lab (DSL) of the Department of Statistics and Actuarial Science (SAAS) at The University of Hong Kong (HKU) has successfully organised the “AI Robotics Vision and Automation Technology Challenges Competition 2021” in collaboration with various companies and corporate sponsors, including Marvel Digital AI Limited, PricewaterhouseCoopers (PwC Mainland China and Hong Kong), Power Hub Ltd, Vision Real Capital Limited, Kinth Technology Ltd, etc. Being held for the first time, the competition provided students with real industrial problems to which they have to develop innovative AI (Artificial Intelligence) and IoT (The Internet of Things) solutions by integrating science, AI technology, engineering, statistics and mathematics. There were two categories of contestants, one for students of HKU Master of Data Science and Master of Statistics programmes, another one for students of local secondary schools in STEM education. With the mentoring from the academic staff in the Data Science Lab, industrial partners, and education leaders of the Association of I.T. Leaders in Education, there were a total of 30 groups of contestants participated in the Competition with very high quality proposals and outcomes. After the Competition, Dr Danny HA of the Academy of Professional Certification will offer a mentorship workshop to the winning teams on how to set up a start-up and look for potential funds. The DSL will continue to mentor these students on their innovative entrepreneurship journey. “Our Data Science Lab promotes education through applied research and company consultancy. We teach our students through (i) accelerated learnings (e.g. competition, capstone projects, internship, and consultancy), (ii) company and multi-disciplinary collaborations and innovations (STEMIP - Science, Technology, Engineering, Mathematics, Innovation, Practical), and (iii) applying theories to real practices to create values and impacts to our society,” said Dr Eddy LAM, Director of HKU SAAS Data Science Lab. “Studying should not aim at the grades. Ability to put theories and knowledge into practise is more important.” said Professor Guosheng YIN, Head of HKU Department of Statistics and Actuarial Science. “The HKU’s (3+1)Is strategy integrates Internationalisation, Innovation and Interdisciplinarity to create collective Impact. Our Data Science Lab adds a novel STEMIP education model to the HKU (3+1)Is strategy to put the conceptual ideas into practice.” said Dr Adela LAU, Deputy Director of HKU SAAS Data Science Lab. For more details about the winning proposals and the Competition, please visit here.    The winning team of the university category, with Dr Eddy Lam, Director of the HKU SAAS Data Science Lab (second from the right) and Dr Adela Lau, Deputy Director of the HKU SAAS Data Science Lab (fourth from the right). The winning team of the secondary school category, with Professor Guosheng Yin, Head of HKU Department of Statistics and Actuarial Science (leftmost), Dr Eddy Lam, Director of HKU SAAS Data Science Lab (rightmost), Dr Adela Lau, Deputy Director of HKU SAAS Data Science Lab (second from the right), and Mr Tung-Shek Wong, STEM teacher of Heung To Secondary School – Tseung Kwan O (third from the right).   Winning Project of University Group:   AI in Behavioural Intelligence - Artificial Intelligence Video Interview Analyser By Dr Adela LAU (Mentor), Jason Jin An CHAN, Si Man TONG, Tsin Wai YAU, and Tsz Hin CHAN from the MSc in Statistics Program of Department of Statistics and Actuarial Science of HKU The Master of Statistics programme of the HKU SAAS Department developed an Artificial Intelligence Video Interview Analyser to analyse the facial expression of the candidates during interview, to assess the candidate’s job knowledge with written assessment, and to calculate and visualise the candidate’s overall performance respectively, which can help the interviewees to achieve better performance at job interviews.   STEMIP Junior Nurture Program and Winner of Secondary School Group:  AI in Smart City - Driver Drowsiness Detection System By Tung Shek WONG (Mentor), Ho Shun Louisa LOUIE, Lo Yi Tiffany WONG, Chun Ting Issac WONG, Hin Wing Max TIN, Chung Ho Danny TSANG from Heung To Secondary School – Tseung Kwan O The system can detect and analyse drivers’ drowsiness by simple arithmetic operation. Transport companies can then analyse the statistics and schedule the rest time of the drivers to ensure that no driver works in a fatigue status. The experimental results showed that the system is able to detect the driver’s drowsiness with 95% accuracy, even when the driver wears a mask or glasses.           

NEWS DETAIL

HKU scientists reveal orally administrated bismuth drug together with N-acetyl cysteine as a potential broad-spectrum anti-coronavirus cocktail therapy

A research team led by Professor Hongzhe SUN, Norman & Cecilia Yip Professor in Bioinorganic Chemistry from the Department of Chemistry, Faculty of Science, the University of Hong Kong (HKU), in collaboration with Dr Shuofeng YUAN, Assistant Professor from the Department of Microbiology, Li Ka Shing Faculty of Medicine, discovered that orally administrated bismuth drug colloidal bismuth subcitrate (CBS) together with N-acetyl cysteine (NAC) could be a broad-spectrum anti-coronavirus cocktail therapy. Oral administration of the cocktail suppresses the replication cycle of the virus, reduces viral loads in the lung and ameliorates virus-induced pneumonia in a hamster infection model. Not only could NAC stabilise bismuth-containing metallodrugs at stomach-like conditions but also enhance the uptake of bismuth drugs in tissues (e.g. lung) and antiviral potency through oral administration. Bismuth subsequently suppressed virus replication of a panel of clinically relevant coronaviruses, including Middle East respiratory syndrome-related coronavirus (MERS-CoV), Human coronavirus 229E (hCoV-229E) and Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its alpha variant (B.1.1.7) by inactivating multiple essential viral enzymes. The findings provided insights into the development of inorganic pharmaceutics and a new therapeutic approach for viral infections. The ground-breaking findings have been published in a leading chemical journal, Chemical Science and a related patent has been filed in the US.   Background SARS-CoV-2 is the causative agent of the Coronavirus Disease 2019 (COVID-19) pandemic which leads to around five million confirmed cases, including 323,000 deaths globally. Although several vaccines have been approved for emergency use worldwide, increasing cases of people getting infected with COVID-19 are reported despite being fully vaccinated. The emergence of SARS-CoV-2 variants like Omicron and Delta variants associated with enhanced transmissibility and reduced sensitivity to vaccine-induced protection poses a continuous threat to global health. There is an urgent need for safe and effective therapeutic options for COVID-19 which remain scarce. Remdesivir was the first drug approved by the US Food and Drug Administration (FDA) for the treatment of COVID-19. However, patients can only receive remdesivir treatment via intravenous route as in-patients as the oral formulation of this drug is still not available. For most COVID-19 patients with mild to moderate disease, an orally available anti-SARS-CoV-2 drug would help to facilitate out-patient treatment and reduce the burdens of healthcare facilities. Even though the US FDA issued emergency use authorisation for the oral tablet-form candidates from pharmaceutical giants Pifzer and Merck which reported significant reduction of the risk of hospitalisation or death, their antiviral efficacy, long-term safety and worldwide availability spark uncertainties. Therefore, it is of utmost urgency for renewed efforts to evaluate the existing repertoire of FDA-approved drugs on a wider scale and by a novel strategy.   Key findings The research team previously screened a set of metallodrugs and related compounds and identified ranitidine bismuth citrate (RBC, commercial name: Pylorid), a drug in clinical use for the treatment of Helicobacter pylori infection, as a potent anti-SARS-CoV-2 agent both in vitro and in vivo. Pylorid exhibited low cytotoxicity and protected SARS-CoV-2-infected cells with a high selectivity index which demonstrated the high clinical potential of bismuth(III)-drugs or other metallodrugs for the treatment of SARS-CoV-2 infection. The related works were published in Nature Microbiology in 2020. RBC, as well as other related bismuth drug(s), e.g., colloidal bismuth subcitrate (CBS) and bismuth salicylate (BSS), acts to precipitate in gastric juice and form a protective coating on the gastric wall, which leads to a hindered absorption in gastrointestinal tract. The findings revealed that NAC could prevent the hydrolysis of CBS in simulated gastric juice buffer (pH 1.2) and sodium bicarbonate buffer (pH 9.2), which form a highly stable and water-soluble Bi(III) thiolate complex, [Bi(NAC)3]. The combined use of NAC could significantly enhance the permeability of bismuth in parallel artificial membrane model, the human intestinal epithelial cancer cell line (Caco-2) model, and a modified ex vivo everted rat gut sac model. The thiolated bismuth could undergo fast thiol exchange with thiol groups in glycoproteins, which potentially increase both the lipophilicity and membrane permeability of bismuth, thus further enhancing the oral absorption of bismuth drugs. The in vivo pharmacokinetics data also consistently demonstrate that compared with the administration of CBS in the absence of NAC, the co-administration of CBS with NAC led to a remarkably improved bismuth uptake profile in both blood and lung tissues. The studies demonstrated the oral efficacy of CBS+3NAC as well as BSS+3NAC on the suppression of SARS-CoV-2 replication in vivo as evidenced by the substantial reduction of viral loading in the lungs based on viral RNA genome copy number and the ameliorated virus-associated lung pathology after oral administration of CBS+3NAC. The therapeutic dosage of drugs induced only reversible nephrotoxicity and no systematic toxicities. More importantly, CBS+3NAC inhibits the replication of a broad range of epidemic and seasonal CoVs, including SARS-CoV-2 (B.1.1.7), MERS-CoV, and hCoV-229E. The pan-inhibitory activity of bismuth drugs against various CoVs may stem from their abilities to target multiple key viral cysteine enzymes in the viral replication cycles, including papain-like protease (PLpro), main protease (Mpro), helicase (Hel) and angiotensin-converting enzyme 2 (ACE2).   Image 1. Combinatorial CBS and NAC exhibit broad-spectrum anti-CoVs potency both in vitro and in vivo. (A) Scheme depicting the therapeutic treatment via oral administration of vehicle, CBS (300 mg/kg) or BSS (300 mg/kg), NAC (370 mg/kg) and CBS (300 mg/kg)+3NAC (370 mg/kg) or BSS (300 mg/kg)+3NAC (405 mg/kg), given at Day -2, -1, 0 and 1 and the hamsters were challenged by virus at Day 0; Tissue samples were collected at two days after infection. (B) Viral yield in lung tissue of hamster receiving treatment of vehicle, CBS, NAC, and CBS+3NAC. (C) Viral yield in lung tissue of hamster receiving treatment of vehicle, BBS, and BSS+3NAC. (D) Cytokine IL-6 gene expression level. (E) CBS+3NAC suppressed replication of human-pathogenic coronaviruses in human cellular models in a dose-dependent manner, specifically for SARS-CoV-2 in Vero E6 cells; SARS-CoV-2 (B.1.1.7 variant) in Vero E6 cells; MERS-CoV in Vero E6 cell and HCoV-229E in HELF cell.   Image 2. Proposed mechanism of action for orally administrated colloidal bismuth subcitrate together with N-acetyl cysteine as a broad-spectrum anti-coronavirus cocktail therapy. The pan-inhibitory activity of bismuth drugs against various CoVs may stem from their abilities to target multiple viral enzymes in the viral replication cycles. CBS as well as related metallodrugs could inactivate the viral cysteine protease through either targeting the key cysteine residue in the active site (PLpro and Mpro) or structural zinc-finger domain (PLpro and Hel) or even other zinc metalloproteins in human cells (ACE2) that are tightly associated with viral entry.   Image 3. Professor Hongzhe SUN (Norman & Cecilia Yip Professor in Bioinorganic Chemistry and Chair Professor of Chemistry) and his research team. From the right: Miss Suyu WANG (PhD student, Department of Chemistry); Dr Hongyan LI (Senior Research Assistant, Department of Chemistry); Professor Hongzhe SUN, Dr Runming WANG (Postdoctoral Fellow, Department of Chemistry); Dr Shuofeng YUAN (Assistant Professor, Department of Microbiology, HKUMed); Dr Jasper Fuk-Woo CHAN (Clinical Associate Professor, Department of Microbiology, HKUMed).   About the research team The research was conducted by a team led by Professor Hongzhe SUN, Chair Professor of Chemistry, Department of Chemistry. Professor Hongzhe SUN and Dr Shuofeng YUAN, Assistant Professor from the Department of Microbiology, Li Ka Shing Faculty of Medicine are co-corresponding authors. Postdoctoral fellow Dr Runming WANG, Clinical Associate Professor Jasper Fuk-Woo CHAN and Miss Suyu WANG are co-first authors. Other HKU scientists contributing to the research included Dr Hongyan Li, Senior Research Assistant (Chemistry), Postdoctoral fellow Dr Jiajia Zhao (Pharmacy, CUHK), Miss Tiffany Ka-Yan Ip, PhD student (Chemistry), Professor Joan Zhong ZUO, Professor (Pharmacy, CUHK), Professor Kwok-Yung YUEN, Chair Professor (Department of Microbiology, HKUMed). The work was supported by Innovation Research Commission, Research Grants Council, Health and Medical Research Fund of Hong Kong SAR,  and The University of Hong Kong. About Professor Hongzhe SUN and Dr Shuofeng Yuan Professor Hongzhe SUN is a Norman & Cecilia Yip Professor in Bioinorganic Chemistry and Chair Professor of Chemistry at The University of Hong Kong. His research focuses on metalloproteins, the discovery of antimicrobial agents, and inorganic chemical biology.  More information about Professor Hongzhe SUN and his research group can be found from their group’s webpage:  https://chemistry.hku.hk/staff/hzsun/labPage/index.html Dr Shuofeng Yuan is an Assistant Professor at the Department of Microbiology and State Key Laboratory of Emerging Infectious Diseases, The University of Hong Kong. More information about Dr Shuofeng Yuan, and his research group can be found from their group’s webpage:   http://www.microbiology.hku.hk/02_HKU_Staff_Dr_SY_Yuan.html About the research paper:https://doi.org/10.1039/D1SC04515F  

NEWS DETAIL

Faculty of Science scoops four awards in 2021/22 Collaborative Research Fund (CRF) Group Research Projects

In the latest announcement of the Research Grants Council (RGC) in the 2021/22 funding exercise, the Faculty of Science has secured exceptional results under the Collaborative Research Fund (CRF). Established by the University Grants Committee (UGC), the award of CRF Group Research Projects is to encourage and support multi-investigators in diverse disciplines to engage in more creative and high-quality cross-disciplinary projects. Among the 25 CRF Group Research Projects funded by the RGC, HKU has been funded with seven projects as coordinating institution, in which four led by the Faculty have secured a funding of over HK$24.8 Million. Among the four awarded projects, two are from Department of Chemistry, one from Earth Sciences and the other one from Physics. Details of the awarded projects are appended below: Department Project Title Project Coordinator RGC  Fund Approved Project Period Chemistry Functional supramolecular and metallosupramolecular materials and biomaterials — From synthetic challenges to controlled supramolecular assembly, functions and application studies 超分子和金屬超分子功能材料及生物材料  - 從合成挑戰到超分子可控組裝、功能及應用研究 Professor Vivian Wing Wah YAM HK$7,480,000 3 years Chemistry Active fluid for enhanced thermal transport and energy harvesting 活性流體在傳熱和能源回收中的應用 Dr Jinyao TANG HK$4,559,740 3 years Earth Sciences Characterisation of ancient lake basins on Mars using advanced topographic modelling and innovative spectroscopic techniques 基於先進地形建模與創新光譜技術的火星老湖泊盆地特徵研究 Dr Joseph MICHALSKI   HK$4,621,350   3 years Physics Transport and dynamics of correlated quantum matter 關聯量子物態中的輸運和動力學 Professor Shunqing  SHEN HK$8,160,000 3 years   HKU Vice-President and Pro-Vice-Chancellor (Research) Professor Max Shen congratulated all successful applicants and their research teams. He said: “The grants are clear demonstration of the research competitiveness of the University’s faculties and investigators. Their success in obtaining funding further recognised the University’s excellent performance in teaching, learning, and research, and our researchers’ outstanding achievements and strengths. I hope HKU members will continue to address important problems in their fields with innovative ideas, so as to elevate the University’s research in a wide range of areas to world leading levels.” For more details about the funding results, please click here .

NEWS DETAIL

HKU scientists discover activation mechanisms in soybean for adaptation to saline soil in hope of improving agriculture productivity

Farmlands are turning more saline due to climate change, rising sea levels, expanding drylands, and groundwater depletion. This crisis is exacerbated by unsustainable farming practices. The resulting loss in crop yield threatens malnourished populations across the globe. Therefore, scientists are finding ways to boost crop resilience to salt stress to safeguard food security on this planet. Professor Mee-Len CHYE, Wilson and Amelia Wong Professor in Plant Biotechnology, and Dr Terry Shiu-Cheung LUNG, Research Assistant Professor, from the School of Biological Sciences at the University of Hong Kong (HKU) have unveiled the molecular mechanisms activating salt-induced adaptive changes in soybean, bringing hope in providing possible solutions for saline agriculture. The findings, published in the prestigious scientific journal The Plant Cell, offer new strategies to help plants combat soil salinity.   Background Plants as sessile organisms strive for survival upon salt-induced stress by prompting actions including the modification of root architecture, generation of ion pumps, and production of specific metabolites. Acclimation requires numerous stress signalling molecules such as those belonging to two important lipid classes, termed ‘phosphatidic acid’ and ‘oxylipins’. Earlier, Professor Chye’s research team had shown that the generation of phosphatidic acid signals could be facilitated by a Class II acyl-CoA-binding protein (ACBP). ACBPs are highly conserved in eukaryotes and bind acyl-CoA esters, the activated form of fatty acids in lipid metabolism. However, the processes that trigger the synthesis of oxylipins, the oxygenated derivatives of polyunsaturated fatty acids, and crosstalk between phosphatidic acid and oxylipin signals had remained elusive until now.   Key findings When Professor Chye’s team examined soybean roots in a salt solution, surprisingly Class II ACBP3 and ACBP4 variant proteins smaller than the native forms emerged during the first few hours of treatment. “These proteins were truncated because their pre-mRNAs were cut and rejoined in an atypical way, commonly known as ‘alternative splicing’. Luckily, we caught them at the right moment to discover this phenomenon never before seen in plant ACBPs,” commented Professor Chye. Her research team found that the overexpression of the native and truncated ACBP4 rendered soybean hairy roots more salt-sensitive and salt-tolerant than the control, respectively (see Figure 1). Similarly, transgenic Arabidopsis overexpressing truncated ACBP3 were more salt-tolerant than the control, while transgenic Arabidopsis overexpressing native ACBP3 and ACBP4 were more salt-sensitive (see Figure 2). From microscopy, molecular and biochemical analyses, a model (see Figure 3) was formulated to illustrate the mechanistic role of ACBP3 and ACBP4 in activating the generation of oxylipin signals, as well as crosstalk between oxylipins and phosphatidic acid during signalling. Professor Chye briefly explained, “Oxylipin signals are generated by lipoxygenases. Under normal conditions, the enzymes are inactive when they complex reversibly with ACBPs and acyl-CoAs. Under salinity, the enzymes are activated when phosphatidic acid and truncated ACBPs compete for binding with the components of this complex, which eventually dissociates.” Professor Chye hopes to unveil other components in the oxylipin signalling mechanism to further understand the salinity response. Apart from that, her team is currently exploring the potential of enhancing salt tolerance in soybean and other plant crops by a genetic engineering approach. If this innovation is successfully implemented, crop yield will be less impacted by soil salinity to promote food production in view of climate change. Professor Chye also expressed that there is no greater honour than receiving an endowed professorship established with a generous donation from Dr Wilson and Mrs Amelia Wong for using plant biotechnology to ensure food supply for a sustainable future.   Figure 1. Overexpression of truncated ACBP4 variant promotes salt tolerance in soybean hairy roots. Soybean hairy roots overexpressing the native (bottom middle) and truncated (bottom right) forms of ACBP4 were more salt-sensitive and salt-tolerant than the vector-transformed control (bottom left), respectively. Under normal conditions, the hairy roots of all genotypes grew similarly (top panels). Scale bar = 1 cm.   Figure 2. Overexpression of truncated ACBP3 variants promotes salt tolerance in Arabidopsis. Transgenic Arabidopsis overexpressing the native Class II ACBPs and truncated ACBP3 variants were more salt-sensitive and salt-tolerant than the vector-transformed control, respectively. Scale bar = 1 cm.     Figure 3. Model for ACBP3/ACBP4-regulated generation of oxylipin signals during the salinity response. Under normal conditions, ACBP binding with acyl-CoAs (C18:2 and C18:3-CoAs) facilitates sequestration of an inactive lipoxygenase. High salinity triggers dissociation of this complex by a dual mechanism. First, phosphatidic acid signals compete with acyl-CoAs for ACBP binding. Second, pre-mRNAs are cut and rejoined in an unusual way (known as alternative splicing) to produce ACBP variants lacking the lipoxygenase-interacting domain. Thus, the lipoxygenase is activated to generate oxylipin signals for adaptive responses.   About the research team The research team was led by Professor Mee-Len CHYE, Wilson and Amelia Wong Professor in Plant Biotechnology from the School of Biological Sciences at HKU. This project was conducted in collaboration with Professor Hon-Ming LAM, Choh-Ming Li Professor of Life Sciences at The Chinese University of Hong Kong and Director of the State Key Laboratory of Agrobiotechnology (CUHK). Dr Terry Shiu-Cheung LUNG, Research Assistant Professor from the School of Biological Sciences at HKU, is the first and co-corresponding author of the journal paper. Other HKU scholars who contributed to this research include Ms Sze Han LAI, Dr Haiyang WANG, Ms Xiuying ZHANG, Dr Ailin LIU, and Dr Ze-Hua GUO. This work was supported by the Wilson and Amelia Wong Endowment Fund, Hong Kong Research Grants Council Areas of Excellence Scheme (AoE/M-403/16), and Innovation and Technology Fund (Funding Support to State Key Laboratory of Agrobiotechnology).   About the paper The journal paper entitled “Oxylipin signaling in salt-stressed soybean is modulated by ligand-dependent interaction of Class II acyl-CoA-binding proteins with lipoxygenase” was published by Shiu-Cheung Lung, Sze Han Lai, Haiyang Wang, Xiuying Zhang, Ailin Liu, Ze-Hua Guo, Hon-Ming Lam and Mee-Len Chye in The Plant Cell. The full text of this paper is open for free access from here.  For details on Wilson and Amelia Wong Professorship in Plant Biotechnology, please visit here.             

NEWS DETAIL

Three Faculty members received awards under the HKU Outstanding Researcher Awards Scheme 2020 - 21

Congratulations to our academics for their receiving of the University’s awards for research excellence under the Outstanding Researcher Awards Scheme 2020-21, in which Professor Guochun ZHAO was awarded the highest honour ‘Distinguished Research Achievement Award (DRAA)’ for his exceptional contributions in his research in precambrian geology, metamorphic geology and supercontinents in Earth’s history. The list of award recipients is appended as follows:  Distinguished Research Achievement Award (DRAA) - Professor Guochun ZHAO, Department of Earth Sciences Outstanding Young Researcher Award (OYRA) - Dr Zhiwen ZHANG, Department of Mathematics  Research Output Prize (ROP) - Faculty of Science - Dr Alex WEBB, Department of Earth Sciences *Details of the awarded journal paper: 'Breaking Earth's shell into a global plate network', Nature Communications, 2020, Vol. 11, 3621 by C.A. Tang, A.A.G. Webb*, W.B. Moore, Y.Y. Wang, T.H. Ma, T.T. Chen. Professor Max SHEN, the Vice-President and Pro-Vice-Chancellor (Research) of HKU extended his heartfelt congratulations to the award recipients on their outstanding achievements, 'They are role models for all academics of HKU while we are gearing for excellence, quality and impact in the research, innovation and knowledge transfer endeavours.'  The Outstanding Researcher Awards scheme aims to recognise, honour and reward exceptional work in research by staff of the University. The scheme includes the Distinguished Research Achievement Award (DRAA), Outstanding Researcher Award (ORA), Outstanding Young Researcher Award (OYRA), Outstanding Research Student Supervisor Award (ORSSA), and Research Output Prize (ROP). The DRAA, ORA and OYRA are awards made to recognise individuals for their outstanding research accomplishments. The ORSSA is to recognise exemplary and effective supervisory guidance and support to their research postgraduate students. The ROP is a Faculty-based award to honour the best research output from each Faculty.  

NEWS DETAIL