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Skull of the early-diverging oviraptorosaurian pennaraptoran Incisivosaurus. This specimen IVPP V13326 is ~10cm long. Later-diverging oviraptorosaurians lost their teeth and evolved a beak. Image credit: Xing Xu & Waisum Ma

24 Aug 2020

Landmark HKU-led volume on past progress and new frontiers in the study of early birds and their close relatives

The origins of birds and their flight was a major event in the history of life. A wealth of spectacular fossils has demonstrated that birds are theropod dinosaurs, with Pennaraptora being the most relevant subgroup to transition from non-avian dinosaurs to birds. Here we announce the publication of a landmark journal volume on pennaraptoran theropods (Figure 1) edited by HKU Research Assistant Professor Dr. Michael Pittman (Vertebrate Palaeontology Laboratory, Division of Earth and Planetary Science & Department of Earth Sciences) and Prof. Xing Xu of the Institute of Vertebrate Paleontology and Paleoanthropology (IVPP) and the Chinese Academy of Sciences Center for Excellence in Life and Paleoenvironment (Beijing, China), who both specialise in these animals (see Notes). Pennaraptora comprises of birds as well as the pennaceous feathered dromaeosaurids (‘raptors’), troodontids, scansoriopterygids and oviraptorosaurians (Figures 2 and 3). Fossils and insights from living birds and crocodilians show that many important avian traits originated deep within theropod evolutionary history, accumulating over a significant period of time and portion of the evolutionary tree, often in a complex mosaic way. These traits include ‘warm-bloodedness’, unique reproductive strategies as well as flight itself. Key features necessary for flight appeared among pennaraptoran theropods including: a long, robust and sideways-facing arm; a refined “flight-ready” brain; and large, vaned flight feathers. Proxies for modern flight capability, modelling work and functional morphology support flight and near-flight capabilities among paravian pennaraptorans, with powered flight evolving independently multiple times. Breaking new ground in the field To deepen our understanding of avian and flight origins as well as other important pennaraptoran evolutionary events, the International Pennaraptoran Dinosaur Symposium (IPDS) was held at The University of Hong Kong between March 29 and April 1, 2018, to make substantial advances in our understanding of pennaraptoran palaeobiology and evolution (see Notes). These efforts culminated in a special volume just published in the prestigious journal Bulletin of the American Museum of Natural History, entitled ‘Pennaraptoran Theropod Dinosaurs: Past Progress and New Frontiers’, edited by Dr. Pittman and Prof. Xu. “The volume documents past progress, works toward consensus on key unresolved issues, breaks new ground in the field and identifies priority areas for future research”, said Dr. Pittman. Asked about who was involved, Prof. Xu replied, “The volume involved 49 experts from more than 10 countries whose views cover much of the current discussion on pennaraptoran palaeobiology and evolution.” The volume is made up of 14 chapters organised in three sections: Section 1. Fossil Record, Systematics, and Biogeography surveys the pennaraptoran fossil record and draws attention to what new discoveries would help to answer pressing questions in the field. It also presents the current state of pennaraptoran evolutionary relationships (Figure 2), providing the context needed to understand pennraptoran evolution. This section includes the first quantitative analysis of the spatial distribution of coelurosaurian theropods through time (palaeobiogeography; Figure 3), which allowed key tectonic drivers of their evolution to be identified. Section 2. Anatomical Frontiers focuses on recent discoveries in pennaraptoran anatomy, particularly of the hand and head (Figure 4). It explores the implications this knowledge has and will have on our understanding of pennaraptoran palaeobiology and evolution. These discoveries involve a wide range of adopted approaches, including geometric morphometrics, mechanical advantage calculations, and evo-devo approaches as well as the evolutionary context provided in section one. Section 3. Early Flight Study: Methods, Status, and Frontiers begins by detailing the methods currently available for studying early theropod flight and discusses the priorities to address in future methodological development work. Then recent advances in soft-tissue imaging are married with quantitative methods of early flight study to create a new framework on which to build (Figure 5). This section also covers recent efforts to identify the small pennaraptorans that first took to the skies, what their flight capabilities were and how their flight might have been acquired. A new broader context is proposed for flight behaviour as part of a functional landscape. Wing-assisted incline running (WAIR), a behaviour seen in modern birds that is proposed as an early stage of flight development, is argued as a later innovation based on a study of modern ostriches. Asked about the significance of the volume, contributor Dr. Daniel J Field of Cambridge University (Department of Earth Sciences) said, “This is a landmark volume that advances our understanding of pennaraptoran dinosaurs and identifies key areas to address in the years ahead.” Contributor Dr. T Alexander Dececchi of Mount Marty University (Department of Biology) added, “The volume is of particular interest to dinosaur palaeontologists and ornithologists, but its findings will also excite the general public.” The volume is published in the Bulletin of the American Museum of Natural History and can be accessed here: http://digitallibrary.amnh.org/handle/2246/7237 Figure 1. ‘Pennaraptoran Theropod Dinosaurs: Past Progress and New Frontiers’, a landmark volume on the biology and evolution of early birds and their close relatives. The volume comprises of 14 chapters authored by 49 authors from more than 10 countries. Fossil pennaraptorans come in a huge array of shapes and sizes and lived in a range of habitats. However, they shrank drastically in their successful conquest of the skies. Today, they are only survived by the birds. Image credit: Bulletin of the American Museum of Natural History & Julius T Csotonyi. Figure 2. Evolutionary tree of pennaraptoran theropods. Pennaraptora comprises of oviraptorosaurians, scansoriopterygids, birds and their closest relatives, the dromaeosaurids (‘raptors’) and troodontids. Image credit: Pittman et al. 2020. Figure 3. Pennaraptoran fossil localities through time. Pennaraptorans became globally widespread before the end of the Cretaceous and lived in a range of habitats including hot deserts and temperate forests. Image credit: Pittman et al. 2020. Figure 4. Skull of the early-diverging oviraptorosaurian pennaraptoran Incisivosaurus. This specimen IVPP V13326 is ~10cm long. Later-diverging oviraptorosaurians lost their teeth and evolved a beak. Image credit: Xing Xu & Waisum Ma. Figure 5. The early short-tailed fossil bird Sapeornis. Under Laser-Stimulated Fluorescence, the feathers and other soft tissues preserved around the fossil skeleton become clear. This new information is used to refine the reconstruction of its soaring abilities. This specimen STM 15-15 is ~30cm long. Image credit: Serrano et al. 2020. Notes: Most close relatives of birds neared the potential for powered flight but few crossed its thresholds (Aug 2020): https://www.hku.hk/press/press-releases/detail/21405.html Ancient birds out of the egg running(May 2019): https://www.hku.hk/press/press-releases/detail/19256.html HKU imaging technology shows first discovered fossil feather did not belong to iconic bird Archaeopteryx (Feb 2019): https://www.hku.hk/press/press-releases/detail/19063.html HKU hosts international symposium on the origins of birds and flight and presents related display in the Stephen Hui Geological Museum (March 2018): https://www.hku.hk/press/press-releases/detail/17687.html HKU palaeontologist discovers new bird-like dinosaur with flight associated feathers - Jianianhualong tengi (May 2017): https://www.hku.hk/press/news_detail_16295.html Major breakthrough in knowledge of dinosaur appearance HKU palaeontologist reconstructs feathered dinosaurs in the flesh with new technology (March 2017): https://www.hku.hk/press/press-releases/detail/15989.html Scientists reveal how dinosaurs became able to shake their tail feathers (May 2013): https://www.hku.hk/press/press-releases/detail/9693.html

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The origins of powered flight potential in theropod dinosaurs. Image credit: Julius T Csotonyi / Michael Pittman.

10 Aug 2020

Most close relatives of birds neared the potential for powered flight but few crossed its thresholds

Uncertainties in the evolutionary tree of birds and their closest relatives have impeded deeper understanding of early flight in theropods, the group of dinosaurs that includes birds. To help address this, an international study led by HKU Research Assistant Professor Dr. Michael Pittman (Vertebrate Palaeontology Laboratory, Division of Earth and Planetary Science & Department of Earth Sciences) and co-first-authored by his former Postdoctoral Fellow Dr. Rui Pei (now an Associate Professor at the Institute of Vertebrate Paleontology and Paleoanthropology, Beijing), produced an updated evolutionary tree of early birds and their closest relatives to reconstruct powered flight potential, showing it evolved at least three times. Many ancestors of the closest bird relatives neared the thresholds of powered flight potential, suggesting broad experimentation with wing-assisted locomotion before flight evolved. The ten-man five-country team published their findings in the prestigious high-profile journal Current Biology. “Our revised evolutionary tree supports the traditional relationship of dromaeosaurid (‘raptors’) and troodontid theropods as the closest relatives of birds. It also supports the status of the controversial anchiornithine theropods as the earliest birds”, said Dr. Pei. With this improved evolutionary tree, the team reconstructed the potential of bird-like theropods for power flight, using proxies borrowed from the study flight in living birds. The team found that the potential for powered flight evolved at least three times in theropods: once in birds and twice in dromaeosaurids. “The capability for gliding flight in some dromaeosaurids is well established so us finding at least two origins of powered flight potential among dromaeosaurids is really exciting”, said Dr. Pittman. Crucially, the team found that many ancestors of bird relatives neared the thresholds of powered flight potential. “This suggests that theropod dinosaurs broadly experimented with the use of their feathered wings before flight evolved, overturning the paradigm that this was limited to a much more exclusive club”, added Dr. Pittman. This study is the latest in the Vertebrate Palaeontology Laboratory’s long-term research into the evolution of early birds and their closest relatives (see Notes). Asked about future plans, Dr. Pittman replied, “We have helped to better constrain the broader functional landscape of theropods just before flight evolved and in its earliest stages. We plan to now focus on the dromaeosaurids and early birds that we have shown to have the potential for powered flight to improve our understanding of what it took to fly and why.” Access the paper here View video summary of the study View a shorter no audio video summary Graphical abstract showing a simplified version of the revised evolutionary tree of birds (Avialae) and their closest relatives (non-avialan theropod dinosaurs) and the many ancestors that came close to powered flight potential (orange) but the few that achieved it (green; at least three times: once in early birds and twice among the dromaeosaurids (‘raptors’). Image credit: Michael Pittman and co-authors.

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A structurally complex foundation for coral attachment with additional elements to aid the removal of sediments from the corals. (Photo Credit: AFCD)

04 Aug 2020

HKU architects and marine scientists co-develop novel 3D printed ‘reef tiles’ to repopulate coral communities and conserve biodiversity in Hong Kong

Architects and marine scientists at the University of Hong Kong (HKU) have jointly developed a novel method for coral restoration, making use of specially designed 3D printed artificial ‘reef tiles’ for attachment by corals to enhance their chance of survival in the Hoi Ha Wan Marine Park in Hong Kong waters. The restoration project was commissioned by the Agriculture, Fisheries and Conservation Department (AFCD) as part of the active management of coral communities in the Marine Park. Architects from the Robotic Fabrication Lab, under the Fabrication and Material Technologies Lab of the Faculty of Architecture, and marine scientists from the Swire Institute of Marine Science (SWIMS) of the Faculty of Science at HKU collaborated to produce reef tiles tailored for coral attachment and monitor the development of the coral community in the Marine Park. To help corals survive and thrive The Marine Park is a local biodiversity hotspot accounting for more than three-quarters of reef-building corals in Hong Kong and more than 120 fish species. However, in recent years, gradual deterioration of the coral habitat, a process known as bioerosion, coupled with coral bleaching and mass mortality events in 2015-2016, are putting the future of the coral community at risk. Under the project, 3D printed terracotta ‘reef tiles’, designed and developed by the Robotic Fabrication Lab, covering roughly 40m2 in total, were deployed in July 2020 at three selected sites within the Marine Park, including Coral Beach, Moon Island, and a sheltered bay near the WWF Marine Life Centre. The artificial reef tiles are specially designed to aid coral restoration by providing a structurally complex foundation for coral attachment and to prevent sedimentation, one of the major threats to corals. They provide anchors for corals of opportunity, i.e. dislodged coral fragments that are unlikely to survive on their own, giving them a second chance to thrive. The tiles, seeded with coral fragments, were outplanted in July 2020. Three coral species historically common in the Marine Park, namely Acropora, Platygyra and Pavona, were selected for the study. They have different growth forms, representing the branching ‘staghorn’, massive ‘brain’, and foliose ‘plating’ colony forms, creating a diverse habitat for other marine species. Marine scientists at SWIMS will investigate the success of restoration using the mono-, mix- and polyculture of the three coral species, while researchers will monitor the performance of corals on the tiles for the next one and a half years. The 128 pieces of reef tile with a diameter of 600mm were printed through a robotic 3D clay printing method with generic terracotta clay and then fired at 1125 degrees Celsius. The design was inspired by the patterns typical to corals and integrated several performative aspects addressing the specific conditions in Hong Kong waters. In addition to the novel design of the tiles, the materials used are more eco-friendly than the conventional use of concrete and metal. The tiles were printed in clay and then hardened to terracotta (ceramic) in a kiln. The team plans to expand their collaboration to new designs with additional functions for seabed restoration in the region. The researchers hope that this new method for artificial reef tiles will help to restore corals and conserve biodiversity more effectively, and become a vital contribution to the ongoing global efforts to save the degraded coral reef systems. A structurally complex foundation for coral attachment with additional elements to aid the removal of sediments from the corals. (Photo Credit: Vriko Yu) A 3D designed reef tile was printed through a robotic 3D clay printing method with generic terracotta clay and then fired at 1125 degrees Celsius. (Photo credit for both photos: Christian J. Lange) The 3D printed reef tiles covering roughly 40 sqm in total. (Photo credit: Christian J. Lange)

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The Lobster Eye X-ray Satellite undergoing final tests before launch.

27 Jul 2020

Successful launch of the world’s first soft X-ray satellite with “Lobster-Eye” imaging technology: The Dark Matter Hunter

On July 25, 2020, the “Lobster-Eye X-ray Satellite” was successfully launched into orbit at the Taiyuan Launch Center with the first signal received, riding the Long March 4B lift rocket. The “Lobster-Eye X-ray Satellite” is co-led by Nanjing University (NJU), the Laboratory for Space Research (LSR) of The University of Hong Kong (HKU), the 508 Institute of the Fifth Academy of China Aerospace Science and Technology Corporation (CASC), and Shanghai ASES Spaceflight Technology Co. Ltd. also under the 805 Institute of the Eighth Academy of CASC. It was successfully developed by five years of joint effort by the above outstanding teams. The satellite is equipped with an internally developed “Lobster-Eye” focused X-ray detector and a small high-precision payload platform. During the satellite’s long-term orbit operation, it will verify the ultra-large X-ray field-of-view within the X-ray energy regime and complete several important space X-ray detection experiments. This especially includes carrying out dark matter signal detection research within the X-ray energy regime under earth orbit environment. Based on the “Lobster-Eye” focusing light theory, the X-ray imaging technology was first proposed in the 1970s, with advantages of large field-of-view, small size, light weight and easy assembly, etc., making it highly suitable for space payload applications. The “Lobster-Eye X-ray Satellite” will be the world’s first in-orbit space exploration satellite equipped with such Lobster-Eye focused X-ray imaging technology. Its core payload was technically guided by Nanjing University and jointly manufactured by the 508 Institute of CASC and China Building Materials Academy (CBMA). The satellite launch provides an exciting and new platform to continue these highly effective collaborations for the planned up-coming series of satellites. All the participating research teams and units will endeavour to contribute more efforts in core payload technology breakthrough and enhancing our nation’s independent innovation capabilities in space astronomy, deep space exploration and space remote sensing fields. “I hope this project will lead to important scientific advances that reflect well on our two great universities of HKU and NJU and that will provide additional impetus and incentive for greater and deeper collaborations in the future with the Mainland Space programme and emerging space economy,” said Professor Quentin Parker, Director of HKU LSR. Its successful launch marks an important milestone in the hoped-for the emergence of space science research in the Greater Bay Area and encouraging more scientists in the community to engage in nationwide space science projects. The LSR hopes this iconic scientific endeavour may inspire young minds in the HKSAR and beyond to pursue their space dreams and get involved in Science, Technology, Engineering and Mathematics (STEM). About LSR The LSR is well situated in a dynamic region of Asia to foster links with the space science community in China and globally as is already occurring. The LSR’s interdisciplinary research launches various bids to exploit and access the emerging Mainland funding and research environment. We plan to develop multilateral and strategic partnerships with world-leading space science institutes, and participate in large, international, high-impact space missions. We see this as an effective means to better position the LSR, the Departments of Physics and Earth Sciences and the newly established Research Divisions of the Faculty of Science and so HKU, as a serious node of knowledge, expertise and capacity in space science and related disciplines. The “Lobster-Eye X-ray Satellite” was successfully launched, riding the Long March 4B lift rocket. View video of rocket launch Notes: LSR: www.lsr.hku.hk CASC: https://www.cast.cn/english# The 508 Institute of CASC: https://www.cast.cn/news/4072 Nan Jing University: https://www.nju.edu.cn/EN/ Shanghai ASES Spaceflight Technology Co.Ltd.: http://www.asesspace.com CBMA: http://www.cbma.com.cn/en/about-us/index.jsp

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$Figure 1. A snapshot of a model from the new work, showing the late stages of growth and coalescence of a new global fracture network. Fractures are in black / shadow, and colors show stresses (pink color denotes tensile stress, blue color denotes compres$

19 Jul 2020

“Breaking” news! A new idea on how Earth’s outer shell first broke into tectonic plates

The activity of the solid Earth – for example, volcanoes in Java, earthquakes in Japan, etc – is well understood within the context of the ~50-year-old theory of plate tectonics. This theory posits that Earth’s outer shell (Earth’s “lithosphere”) is subdivided into plates that move relative to each other, concentrating most activity along the boundaries between plates. It may be surprising, then, that the scientific community has no firm concept on how plate tectonics got started. This month, a new answer has been put forward by Dr Alexander Webb of the Division of Earth and Planetary Science & Laboratory for Space Research at The University of Hong Kong, in collaboration with an international team in a paper published in Nature Communications. Dr Webb serves as corresponding author on the new work. Dr Webb and his team proposed that early Earth’s shell heated up, which caused expansion that generated cracks. These cracks grew and coalesced into a global network, subdividing early Earth’s shell into plates. They illustrated this idea via a series of numerical simulations, using a fracture mechanics code developed by the paper’s first author, Professor Chunan Tang of the Dalian University of Technology. Each simulation tracks the stress and deformation experienced by a thermally-expanding shell. The shells can generally withstand about 1 km of thermal expansion (Earth’s radius is ~6371 km), but additional expansion leads to fracture initiation and the rapid establishment of the global fracture network (Figure 1). Although this new model is simple enough – Earth’s early shell warmed up, expanded, and cracked – superficially this model resembles long-discredited ideas and contrasts with basic physical precepts of Earth science. Before the plate tectonic revolution of the 1960’s, Earth’s activities and the distribution of oceans and continents were explained by a variety of hypotheses, including the so-called expanding Earth hypothesis. Luminaries such as Charles Darwin posited that major earthquakes, mountain-building, and the distribution of land-masses were thought to result from the expansion of the Earth. However, because Earth’s major internal heat source is radioactivity, and the continuous decay of radioactive elements means that there is less available heat as time moves forward, thermal expansion might be considered far less likely than its opposite: thermal contraction. Why, then, do Dr Webb and his colleagues think that early Earth’s lithosphere experienced thermal expansion? “The answer lies in consideration of major heat-loss mechanisms that could have occurred during Earth’s early periods.” says Webb. “If volcanic advection, carrying hot material from depth to the surface, was the major mode of early heat-loss, that changes everything.” Dominance of volcanism would have an unexpectedly chilling effect on the Earth’s outer shell, as documented in Dr Webb and co-author Dr William Moore’s earlier work (published in Nature in 2013). This is because new hot volcanic material taken from Earth’s depths would have been deposited as cold material at the surface – the heat would be lost to space. The evacuation at depth and piling up at the surface would have eventually required that the surface material sank, bringing cold material downwards. This continual downward motion of cold surface material would have had a chilling effect on the early lithosphere. Because Earth was cooling overall, the heat production and corresponding volcanism would have slowed down. Correspondingly, the downwards motion of lithosphere would have slowed with time, and thus even as the overall planet cooled, the chilled lithosphere would have been increasingly warmed via conduction from hot deep material below. This warming would have been the source of the thermal expansion invoked in the new model. The new modeling illustrates that if Earth’s solid lithosphere is sufficiently thermally expanded, it would fracture, and the rapid growth of a fracture network would divide the Earth’s lithosphere into plates. Dr Webb and his colleagues continue to explore the early development of our planet, and of the other planets and moons in the solar system, via integrated field-based, analytical, and theoretical studies. Their field-based explorations bring them to far-flung sites in Australia, Greenland, and South Africa; their analytical research probes the chemistry of ancient rocks and their mineral components; and their theoretical studies simulate various proposed geodynamic processes. Together, these studies chip away at one of Earth and planetary science’s greatest remaining mysteries: how and why did Earth go from a molten ball to our plate tectonic planet? The paper is published in Nature Communications and can be accessed here: https://www.nature.com/articles/s41467-020-17480-2

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15 Jul 2020

New Intensive Major in Biological Sciences for 6901 BSc students

Adding to the existing 6 Intensive Majors in 6901 BSc Programme, we are glad to announce that one more accredited major - Biological Sciences has been adapted into Intensive Major. Major in Biological Sciences (Intensive) is accredited by the Royal Society of Biology, and it requires students to take 144 credits in order to fulfill programme requirement. Intensive Major programmes allow students to specialise in a science discipline with enriched subject knowledge, preparing those who intend to pursue research in science with adequate disciplinary expertise in both depth and breadth. With the listing of specialisation in transcript, graduates generally enjoy an advantage at job application and when seeking a chartered degree. Details about Biological Sciences MajorMore about Intensive Majors

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Light and confocal images of Symbiodinium cells living in a host cell. (Photo Credit: Allisonmlewis / CC BY-SA)

08 Jul 2020

HKU study reveals the hidden fight within corals

Researchers from the School of Biological Sciences and Swire Institute of Marine Science at The University of Hong Kong are working to understand how the coral symbiosis may respond to global warming through changes in their microbiome, specifically their symbiotic algae. Using a newly developed method they revealed , which may be a determining factor in the sucthe metabolic function of algae changes in response to competition with other speciescess or failure of certain host-symbiont combinations. The research, published in The ISME Journal, used single-celled algae (dinoflagellates) which were isolated from reef-building corals to understand how hotter ocean temperatures might influence their ability to compete against each other within their coral host. The work builds on decades of research which has honed in on certain types of algal species which confer heat resistance to their host. Why these heat-tolerant species are not more widespread has remained a mystery, until now. “We know that the ability of corals to withstand warming oceans is related to their microbiome. You could say we are asking the same types of questions as a physician: Can we manipulate the host microbiome to improve coral health? Our paper demonstrates that the efficacy of probiotic treatments or assisted evolution might depend on how these microbes interact with each other” explains postdoctoral fellow Dr Shelby McIlroy who co-led the study with PhD student Jane Wong. The experiments were conducted at two temperatures; a heated treatment to simulate a coral bleaching event and an unheated control. The researchers found that the heat-tolerant algae were poor competitors at both temperatures and adopted a “shelter-in-place” strategy by storing more fats and carbohydrates to persist through times of stress. At normal temperatures, the thermally sensitive species grew similarly whether the other species was present or not. However, with warming competition triggered a marked increase in resource consumption, essentially restricting the availability of growth resources to its competitors. What the researchers suggest is that thermally tolerant algae have failed to become more widespread because they are outcompeted in most scenarios and simply the “last-man standing” under conditions unsuitable for other species. The researchers combined three established methods - Fluorescent In-Situ Hybridization (FISH), Flow Cytometry (Flow), and Stable Isotope Analysis (SIA) - to differentiate two species of algae from one another that were grown together in a mixed culture. After introducing isotopically labeled nutrients, the team allowed the cells to assimilate carbon and nitrogen prior to separating them for isotope analysis. In this way they could see if one species was obtaining more resources for growth and reproduction than the other - evidence of competition. They called the method FFS. “FFS is an exciting marriage of established methods. We applied it to an interesting question related to corals, but it can be adapted for any microbial community - such as the human gut. In doing so we can begin to assign metabolic functions to certain bacteria which are known to be present and may express certain genes but whose actual function remains unknown.” said Dr David Baker, Associate Professor of School of Biological Sciences and Swire Institute of Marine Science who supervised the study. This research was funded by the Research Grants Council Hong Kong General Research. About the journal paper Citation: McIlroy S.E., Wong J.C.Y., Baker D.M. (2020). Competitive traits of coral symbionts may alter the structure and function of the microbiome. ISME J. https://doi.org/10.1038/s41396-020-0697-0

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29 Jun 2020

Revisiting energy flow in photosynthetic plant cells

By developing innovative methods to visualize energy changes in subcellular compartments in live plants, the team of Dr Boon Leong LIM, Associate Professor of the School of Biological Sciences of The University of Hong Kong, after showing how chloroplasts optimizes its energy efficiency 2 years ago, recently solved a controversial question in photosynthesis: what is the source of NADH (Reduced Nicotinamide adenine dinucleotide) for mitochondria to generate ATP (Adenosine triphosphate)? The results were just published in the journal Nature Communications. Photosynthesis utilizes light as an energy source for plant chloroplasts to synthesize carbohydrates from water and CO2 molecules. ATPplays an important role in this process, as it promotes plant growth and supply energy for various cellular activities. It had been a general belief that mature plant chloroplasts can import ATP from cytosol since 1969, but it was shown to be untrue by Dr Lim and his team in 2018 (Note 1), through introducing a novel ATP sensor in the subcellular compartments of a C3 model plant, Arabidopsis thaliana. This finding has revised our understanding on chloroplast bioenergetics during daytime and nighttime and how mature chloroplasts optimize energy efficiency. Another unresolved problem in photo-energy is that the source of NADH as a fuel for mitochondria (the major ATP synthesizing organelle in cells) to produce ATP during photosynthesis is unclear. Some researchers suggested that excess reducing equivalents carried by surplus NADPH (Reduced Nicotinamide adenine dinucleotide phosphate) can be exported to the cytosol in the form of malate, which can then enter mitochondria through the malate-OAA shuttle, and converted into OAA and NADH in the mitochondrial matrix. On the other hand, some researchers proposed that during photorespiration glycine decarboxylase generates a large amount of NADH in mitochondria for ATP production and surplus reducing equivalents carried by NADH is exported by the mitochondrial malate-OAA shuttle to the cytosol. In the above two pathways, the directions of the malate-OAA shuttle across the mitochondrial membrane during photosynthesis are opposite to each other and therefore this issue had been a matter of debate. To study this problem, Dr Lim’s group introduced two novel sensors that measure real-time dynamic changes in NADPH levels and NADH/NAD+ ratios (this ratio reflects the reduction/oxidation status of the cellular compartments) in Arabidopsis thaliana. The conventional detection methods require extraction and purification of plant metabolites and determination by chemical methods. These methods have a few drawbacks: in planta measurement and real-time dynamic measurement not feasible; incapable of measurement the energy molecules in different cell types or different subcellular compartments. “Our novel technique solves all of the problems above. By employing these energy sensors, we found that photorespiration supplies a large amount of NADH to mitochondria during photosynthesis, which exceeds the NADH-dissipating capacity of the mitochondria. Consequently, the surplus NADH must be exported from the mitochondria to the cytosol through the mitochondrial malate-OAA shuttle. (see figure)”, said Ms Sheyli Lim, a PhD student and the first author of a manuscript published in Nature Communications. “Solving this question allows us to understand more about the energy flow between chloroplasts and mitochondria during photosynthesis, which could help us to booth the efficiency of photosynthesis in the future”. “We are the first group to introduce these three novel energy sensors in plants. They will have wide applications in researches regarding plant bioenergetics. Now we are employing them to study bioenergetics of guard cells, pollen tube growth and C4 plants with international collaborators,” said Dr Lim. “It is a great satisfaction to revisit and clarify some general believes in my field. I wish our findings can eventually help humans to boost agriculture production,’ he added. Note 1: press release (Oct 2018): https://www.hku.hk/press/press-releases/detail/c_18582.html The paper is published in Nature Communications and can be accessed here: https://www.nature.com/articles/s41467-020-17056-0 7-day-old seedlings with NADPH sensor in plastids

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23 Jun 2020

HKU-codeveloped automated laser-scanning ‘hunter drone’ seeks out fossils, minerals and biological targets

Science fiction has machine-intelligent hunter drones and they have now become science fact with a new HKU-codeveloped autonomous ‘hunter drone’ that seeks out targets at night using a scanning laser (Figure 1). This technique - Laser-Stimulated Fluorescence (LSF) - was codeveloped at HKU and has been highly successful in palaeontology, making fossil bones glow and revealing otherwise invisible details like skin and cartilage (note 1). The application of LSF to an aerial system is possible because of the laser’s ability to project over great distances with little loss in power. HKU Research Assistant Professor Dr Michael Pittman (Vertebrate Palaeontology Laboratory, Division of Earth & Planetary Science and Department of Earth Sciences) and his colleague Thomas G Kaye of the Foundation for Scientific Advancement made this a reality by developing a fully autonomous LSF drone system. “Nicknamed ‘Laser Raptor’, this system is designed to more efficiently seek out fossils exposed on the surface in the field”, said Dr Pittman. Loaded with pre-programmed flight paths during the day, this prototype was launched at night in the badlands of Arizona and Wyoming, USA to search for fossils (Figure 1). Laser Raptor flies rapidly to search locations using its on-board navigation and then descends and maintains an altitude of 4 metres above ground so it can ‘mow the lawn’ in search of glowing targets as small as a thumbnail. After each “mission” is complete, a video of the laser scan is processed to find hot spots that are investigated the next day (Figure 2), leading to the recovery of new fossil specimens (Figure 3). Fluorescence is extremely sensitive to differences in mineral composition. Although Laser Raptor was designed to locate fossils, it is ready to seek out a whole range of fluorescent targets including minerals e.g. to study rare and unusual geology or in search of mining materials like gemstones, certain organisms like scorpions, shellfish and cyanobacteria, and even archaeological artefacts and structures. Asked about future plans, Thomas Kaye replied, “As members of HKU’s Laboratory of Space Research, Dr Pittman and I are currently working to develop LSF applications for the study of geologic landscapes beyond Earth.” Note 1 press release (March 2017): https://www.hku.hk/press/press-releases/detail/15989.html The paper is published in Methods in Ecology and Evolution and can be accessed here: https://besjournals.onlinelibrary.wiley.com/doi/full/10.1111/2041-210X.13402 Please visit the video at here. Figure 2. Hot spot on laser ‘scan strip’ produced by the Laser Raptor drone system is ~2cm wide fragment of a fossil mammal tooth. Image Credit: Thomas G Kaye & Michael Pittman. Figure 3. ~2cm wide fragment of a fossil mammal tooth found using the Laser Raptor drone system. The tooth belongs to a brontothere which lived in ancient Wyoming, USA ~35 million years ago. Scale is 5mm. Image Credit: Thomas G Kaye & Michael Pittman.

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22 Jun 2020

Professor Vivian W W Yam has been bestowed with the most prestigious Porter Medal 2020

Professor Vivian Wing-wah Yam has been bestowed with the most prestigious The Porter Medal 2020. Professor Yam obtained both her BSc(Hons) and PhD from The University of Hong Kong, and is currently the Philip Wong Wilson Wong Professor in Chemistry and Energy and Chair Professor of Chemistry at The University of Hong Kong. She is an elected Member of the Chinese Academy of Sciences, Foreign Associate of US National Academy of Sciences, Foreign Member of Academia Europaea, Fellow of TWAS and Founding Member of Hong Kong Academy of Sciences. She was Laureate of the 2011 L'Oréal-UNESCO For Women in Science Award. Her research interests include inorganic/organometallic chemistry, supramolecular chemistry, photophysics and photochemistry, and metal-based molecular functional materials. She has contributed to the advancement of photochemistry, especially in the area of inorganic and organometallic photochemistry, luminescent metal-ligand coordination complexes and supramolecular assemblies, and photofunctional materials for sensing, organic optoelectronics and solar energy research. Congratulations to Professor Yam! About The Porter Medal The Porter Medal is named after the late George Porter FRS, Nobel Laureate; and is awarded bi-annually to the scientist who has contributed to the science of photochemistry with particular emphasis on more physical aspects, reflecting George Porter’s own interests. Visit the official website

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A Pocillopora damicornis nubbin at the at the coral nursery ground of the InterContinental Moorea Resort & Spa (Moorea, French Polynesia) (Credit: Dr Isis Guibert)

22 Jun 2020

Dimethylsulfoniopropionate concentration in coral reef invertebrates varies according to species assemblages

New research highlights the effect of benthic assemblages on the sulfur metabolism of coral and giant clam species. The research was conducted at CRIOBE and ENTROPIE research units, with the collaboration of the Swire institute of Marine Science of The University of Hong Kong (SWIMS, HKU), Paris-Saclay UVSQ University, The Cawthron Institute (New Zealand) and The University of French Polynesia. The findings were recently published in the journal Scientific Reports. To better understand how benthic species assemblages could influence their respective fitness, the researchers created artificial benthic assemblages using two coral species (Pocillopora damicornis and Acropora cytherea) and one giant clam species (Tridacna maxima) and measured the dimethylsulfoniopropionate (DMSP) concentration in each species using Nuclear Magnetic Resonance (NMR) spectroscopy. DMSP, produced in large quantities in coral reefs, is a key compound that plays a central role in the marine sulfur cycle and climate regulation as major precursor of the volatile compound Dimethylsulfide (DMS). While DMSP has been found in terrestrial and marine organisms, only few species are able to produce it, among them marine algae such as dinoflagellates and corals. Numerous ecological studies have focused on DMSP concentrations in corals, which led to the hypothesis that increases in DMSP levels might be a general response to stress. “We submitted our different assemblages of one, two or three co-occurring species to a thermal stress and measured the DMSP concentration in each species. Interestingly, we demonstrated that the concentration of DMSP in A. cytherea and T. maxima is modulated according to the complexity of species assemblages”, explains Dr Isis Guibert. Coral and giant clams are holobionts living in association with symbiotic algae, Symbiodiniaceae, as well as a large bacterial community. Both, Symbiodiniaceae and bacteria are able to produce DMSP. To determine whether giant clams might also contribute to DMSP production, the team explored transcriptomes of T. maxima for genes encoding enzymes involved in the DMSP biosynthesis. “For the first time, we revealed the existence of homologous genes involved in DMSP production in giant clam genome” said Dr Gaël Lecellier, who supervised the study. “Taken together, our results suggest that DMSP concentration in the holobiont is influenced by their neighboring species, modifying the metabolism of the sulfur pathway”. The findings of this study offer new perspectives for future global sulfur cycling research. The open-access study, led by Dr Gaël Lecellier (Paris-Saclay UVSQ University and ENTROPIE) and postdoctoral fellow Dr Isis Guibert (SWIMS, The University of Hong Kong) was supported by Labex Corail and CNRS fundings. Dr I Guibert received a PhD grant from Sorbonne University. About the journal paper Citation: Guibert I, Bourdreux F, Bonnard I, Pochon X, Dubousquet V, Raharivelomanana P, Berteaux-Lecellier V, Lecellier G (2020) Dimethlysulfoniopropionate concentration in coral reef invertebrates varies according to species assemblages. Scientific Reports. www.nature.com/articles/s41598-020-66290-5 About the research team Dr Isis Guibert is a postdoctoral researcher in the Division of Ecology & Biodiversity and Swire Institute of Marine Science at HKU. She spearheaded the work as part of her PhD at Sorbonne University, in the CRIOBE and ENTROPIE research units. Flavien Bourdreuxis a chemistry engineer at Paris-Saclay UVSQ University. Dr Isabelle Bonnard is a professor associate at Perpignan University at CRIOBE. Dr Xavier Pochon is a science leader at the Cawthron Institute and University of Auckland, New Zealand. Dr Vaimiti Dubousquet is a scientific and technological innovation officer at the Government of French Polynesia. Dr Raharivelomanana Phila is a professor at The University of French Polynesia. Dr Véronique　Berteaux-Lecellier is a CNRS researcher at ENTROPIE research unit. Dr Gael Lecellier is an associate professor at Paris-Saclay UVSQ University at ENTROPIE research unit. An Acropora Cytherea nubbin at the at the coral nursery ground of the InterContinental Moorea Resort & Spa (Moorea, French Polynesia) (Credit: Dr Isis Guibert) Polyps of Pocillopora damicornis (Credit: Dr Isis Guibert) Giant clam Tridacna maxima at the at the coral nursery ground of the InterContinental Moorea Resort & Spa (Moorea, French Polynesia) (Credit: Dr Isis Guibert) Dr. Isis Guibert inspecting a coral nubbin (Credit: Taylor Bogar) Coral and giant clams nursery site at the InterContinental Resort & Spa Moorea in French Polynesia (Credit: CRIOBE) Coral nursery ground of the InterContinental Moorea Resort & Spa (Moorea, French Polynesia) (Credit: Dr Isis Guibert)

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Figure 1. Spin texture and vortex in quantum magnet TMGO when the material is inside the topological KT phase.

15 Jun 2020

Quantum Material research connecting physicists in Hong Kong, Beijing and Shanghai Facilitates discovery of better materials that benefit our society

A visit of Dr Meng (third from the left) from HKU Physics visiting Tianhe-2 supercomputers at the National Supercomputer Center in Guangzhou. A joint research team from The University of Hong Kong (HKU), Institute of Physics at Chinese Academy of Science, Songshan Lake Materials Laboratory, Beihang University in Beijing and Fudan University in Shanghai, provide a successful example of modern era quantum material research. By means of the state-of-art quantum many-body simulations, performed on the world’s fastest supercomputers (Tianhe-I and Tianhe-III protype at National Supercomputer Center in Tianjin and Tianhe-II at National Supercomputer Center in Guangzhou), they achieve accurate model calculations for a rare-earth magnet TmMgGaO4 (TMGO). They found that the material, under the correct temperature regime, could realize the the long-sought-after two-dimensional topological Kosterlitz-Thouless (KT) phase, which completes the pursuit of identifying the KT physics in quantum magnetic materials for half a century. The research work is recently published in Nature Communications. Quantum materials are becoming the cornerstone for the continuous prosperity of human society. From the next-generation AI computing chips that go beyond Moore’s law (the law is the observation that the number of transistors in a dense integrated circuit doubles about every two years, our PC and smartphone are all based on the success of it. Nevertheless, as the size of the transistors are becoming smaller to the scale of nanometer, the behaviour of electrons are subject to quantum mechanics, the Moore’s law is expecting to breakdown very soon), to the high speed Maglev train and the topological unit for quantum computers, investigations along these directions all belong to the arena of quantum material research. However, such research is by no means easy, the difficulty lies in the fact that scientists have to solve the millions of thousands of the electrons in the material in a quantum mechanical way (hence quantum materials are also called quantum many-body systems), this is far beyond the time of paper and pencil, and requires instead modern quantum many-body computational techniques and advanced analysis. Thanks to the fast development of the supercomputing platforms all over the world, scientists and engineers are now making great use of these computation facilities and advanced mathematical tools to discover better materials to benefit our society. The research is inspired by the KT phase theory avocated by J Michael Kosterlitz, David J Thouless and F Duncan M Haldane, laureates of the Nobel Prize in Phyiscs 2016. They were awarded for their theoretical discoveries of topological phase and phase transitions of matter. Topology is a new way of classifying and predicting the properties of materials in condensed matter physics, and is now becoming the main stream of quantum material research and industry, with broad potential applications in quantum computer, lossless transmission of signals for information technology, etc. Back to 1970s, Kosterlitz and Thouless had predicted the existence of topological phase, hence named after them as the KT phase, in quantum magnetic materials. However, although such phenomena have been found in superfluids and superconductors, KT phase has yet been realized in bulk magnetic material. The joint team is led by Dr Zi Yang Meng from HKU, Dr Wei Li from Beihang Univeristy and Professor Yang Qi from Fudan University. Their joint effort has revealed the comprehensive properties of the material TMGO. For example, in Figure 2 (see below), by self-adjustable tensor network calculation, they computed the properties of the model system at different temperature, magnetic field, and by comparing with the corresponding experimental results of the material, they identify the correct microscopic model parameters. With the correct microscopic model at hand, they then performed quantum Monte Carlo simulation and obtained the neutron scattering magnetic spectra at different temperatures (neutron scattering is the established detection method for material structure and their magnetic properties, the closest such facility to Hong Kong is the China Spallation Neutron Source in Dongguan, Guangdong). As shown in Figure 3 (see below), the magnetic spectra with its unique signature at the M point is the dynamical fingerprint of the topological KT phase that has been proposed more than half-a-century ago. Figure 2. Thermodynamic measurements and tensor network fittings to experimental results. Figure 3. Quantum Monte Carlo computed magnetic spectra of TMGO at finite temperatures with comparison with experimental results. “This research work provides the missing piece of topological KT phenomena in the bulk magnetic materials, and has completed the half-a-century pursuit which eventually leads to the Nobel Physics Prize of 2016. Since the topological phase of matter is the main theme of condensed matter and quantum material research nowadays, it is expected that this work will inspire many follow-up theoretical and experimental researches, and in fact, promising results for further identification of the topological properties in quantum magnet have been obtained among the joint team and our collaborators,” said Dr Meng. Dr Meng added: “The joint team research across Hong Kong, Beijing and Shanghai, also sets up the protocol of modern quantum material research, such protocol will certainly lead to more profound and impactful discoveries in quantum materials. The computation power of our smartphone nowadays is more powerful than the supercomputers 20 years ago, one can optimistically foresee that with the correct quantum material as the building block, the personal devices in 20 years can certainly be more powerful than the fastest supercomputers right now, with minimal energy cost of everyday battery.” About the team Dr Zi Yang Meng is the world leading expert in developing and employing large scale quantum Monte Carlo simulation upon quantum many-body systems, and have recently made breakthrough in quantum metal research (Breakthrough in Understanding Quantum Metals: https://www.hku.hk/research/stories/20645/); Dr Wei Li is the developer of state-of-art tensor network approach that could compute the temperature and magnetic field response of quantum many-body systems; Professor Yang Qi performed the quantum field theory analysis of the numerical results and make sense of it all. About the Tianhe Supercomputers Tianhe-1 and Tianhe-2 are the large supercomputers in China, they are among the world fastest supercomputer and were the No.1 in 2010 and 2014 in the TOP500 list https://www.top500.org/. Tianhe-3 supercomputer is expected to be in usage in 2021 and will be world first exaFLOPS scale supercomputer. The quantum Monte Carlo and tensor network simulations performed by the joint team make use of the Tianhe supercomputers and requires the parallel simulations for thousands of hours on thousands of CPUs, it will take more than 20 years to finish if performed in common PC. The work was supported by the Research Grants Council of HKSAR, the Ministry of Science and Technology of China and the National Science Foundation of China. The joint team would in particular like to thank the Computational Initiative at the Faculty of Science and the Information Technology Services at The University of Hong Kong, for their understanding, support and promotion of the large-scale computational oriented researches. Link of journal paper: https://www.nature.com/articles/s41467-020-14907-8

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A model for the antagonism between the HSP and the UPS for controlling the stability of key signaling molecules.

10 Jun 2020

An unexpected heat shock to neurons: HKU scientists and collaborators uncovered a new mechanism for balancing protein stability during neuronal development

Dr Chaogu Zheng’s research team at the School of Biological Sciences of The University of Hong Kong A research team led by Dr Chaogu Zheng from the School of Biological Sciences at The University of Hong Kong (HKU), in collaboration with a team led by Professor Martin Chalfie (2008 Nobel Laureate in Chemistry) from the Department of Biological Sciences at Columbia University, recently discovered an unexpected role of the heat shock proteins (HSPs), also known as the molecular chaperones, during neuronal differentiation, which refers to the process a neuron takes to acquire its shape and function. HSPs are mostly known to protect cells from various stresses, e.g. extreme temperatures, toxins, and mechanical damage, and to safeguard tissue development; this new study, however, suggests that the Hsps can also play an inhibitory role in neuronal differentiation by destabilizing the cytoskeleton of the neurons. The research findings were recently published in a leading international journal in the developmental biology – Development. Protein quality control is important for normal development in human cells, and its dysregulation leads to a range of neurodevelopmental disorders. Inside cells, the Hsps and other chaperones promote protein folding and stability, while the ubiquitination-proteasome system (UPS) targets proteins for degradation. The HSPs and UPS pathways often collaborate to eliminate irreparable proteins in some cellular contexts, but their interaction in developing neurons is not well understood. Using neurons from a model organism called Caenorhabditis elegans, which can be easily genetically manipulated, the research team discovered that when the UPS system is compromised in genetic mutants, a major part of the cytoskeleton called microtubules is destabilized, leading to defects in the axonal growth (axons are the projections of neurons). Surprisingly, through a genetic screen, the team found that deleting the HSPs and co-chaperones can fully rescue the defects caused by the compromised UPS, suggesting that the two systems counter each other during development. Furthermore, a protein kinase called DLK-1 was found to be stabilized by the HSPs and degraded by the UPS. The overabundance of DLK-1 caused instable microtubules and neuronal growth defects. Thus, by regulating the same target proteins, HSPs and UPS can fine-tune the level of critical signaling molecules and create a tightly controlled balance between protein stability and degradation. The discovery of this mechanisms can help understand the molecular basis of neurodevelopmental diseases, nerve regeneration, and neurodegenerative diseases. “This research identifies a previously underappreciated role of HSPs in neuronal development and suggests that HSPs may not be always protective of cellular morphology and functions,” said Dr Zheng. At the same time, this research also opens up a new direction to understand the antagonism between the HSPs and the UPS system in maintaining a balance between protein stabilization and turnover. In the further, Dr Zheng suggests the research will be focused on identifying the common targets of the two HSPs and UPS pathways, which will be the critical control point of not only neuronal development but also neuronal regeneration. Dr Zheng envisions that a complete understanding of the relationship between chaperoning and degradation of proteins can help identify the key therapeutic targets of many neurological diseases. About the research paper The paper is published in Development can be accessed here: “Opposing effects of an F-box protein and the HSP90 chaperone network on microtubule stability and neurite growth in Caenorhabditis elegans” Link: https://dev.biologists.org/content/early/2020/05/24/dev.189886 This work is supported by funding from The University of Hong Kong, Research Grant Council of Hong Kong, and The Institute of Health of United States.

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Mangroves are amongst the most valuable of natural ecosystems, supporting coastal fisheries and biodiversity. (Photo courtesy：Nicole Khan)

05 Jun 2020

Mangroves at risk of collapse if emissions not reduced by 2050, international scientists predict

An international research team comprising scientists from The University of Hong Kong,　the Nanyang Technological University, Singapore (NTU Singapore), Macquarie University and the University of Wollongong (Australia) as well as Rutgers University (USA) has predicted that mangroves will not be able to survive with rising sea-level rates reached by 2050, if emissions are not reduced. The team’s findings were recently published in one of the world's top peer-reviewed academic journal Science. Using sedimentary archives from the Earth’s past, researchers estimated the probability of mangrove survival under rates of sea-level rise corresponding to two climate scenarios – low and high emissions. When rates of sea-level rise exceeded 6 mm per year, similar to estimates under high emissions scenarios for 2050, the researchers found that mangroves very likely (more than 90% probability) stopped keeping pace. In contrast, mangroves can survive sea-level rise by building vertically when the rise remains under 5 mm per year, which is projected for low emissions scenarios during the 21st century. The threshold of 6 mm per year is one that can be ‘easily surpassed’ on tropical coastlines – if society does not make concerted efforts to cut carbon emissions, said lead investigator of the study, Professor Neil Saintilan, from the Department of Earth and Environmental Sciences at Macquarie University. Professor Saintilan said, “We know that sea-level rise is inevitable due to climate change, but not much is known about how different rates of sea-level rise affect the growth of mangroves, which is an important ecosystem for the health of the earth.” "Most of what we know about the response of mangroves to rising sea level comes from observations over the past several years to decades when rates of rise are slower than projected for later this century. This research offers new insights because we looked deeper into the past when rates of sea-level rise were rapid, reaching those projected under high emissions scenarios," said Dr Nicole Khan, Assistant Professor of Department of Earth Sciences, The Unviersity of Hong Kong. Why mangroves matter With their iconic roots that rise from under the mud, mangrove stands grow in a process called vertical accretion. This feature is crucial to the ecosystem as it helps to soak up greenhouse gas emissions (carbon sequestration) at densities far greater than other forests, and provides a buffer between the land and sea - helping protect people from flooding on land. The study, which covered 78 locations over the globe, explores how mangroves responded as the rate of sea-level rise slowed down from over 10 mm per year 10,000 years ago to nearly stable conditions 4,000 years later. The drawdown of carbon as mangrove forests expanded over this time period contributed to lower greenhouse gas concentrations. The study found that mangroves will naturally encroach inland if its ability to vertically accrete is hindered. “Our results underscore the importance of adopting coastal management and adaptation measures that allow mangroves to naturally expand into low-lying coastal areas to protect these valuable ecosystems," said Dr Khan. Professor Benjamin Horton, Chair of the Asian School of the Environment at NTU Singapore, who co-authored the paper, said, “In 30 years, if we continue upon a high-emissions trajectory, essentially all mangroves, including those across southeast Asia, will face a high risk of loss.” “This research therefore highlights yet another compelling reason why countries must take urgent action to reduce carbon emissions. Mangroves are amongst the most valuable of natural ecosystems, supporting coastal fisheries and biodiversity, while protecting shorelines from wave and storm attack across the tropics,” Professor Horton added. Paper titled “Thresholds of mangrove survival under rapid sea-level rise”, published in Science, June 5 2020. Dr Nicole Khan (right) and her colleague investigating the growth of mangroves. (Photo courtesy：Nicole Khan) Mangroves along the river side of West Alligator, Australia. (Photo courtesy：Kerrylee Rogers) This mangrove roots help to soak up greenhouse gas emissions at densities far greater than other forests. (Photo courtesy：Nicole Khan)

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The architecture of the proposed lesion-attention deep neural networks.

02 Jun 2020

Statisticians have developed an online diagnostic system with AI technologies based on COVID-19 chest CT dataset for screening suspected cases

From the left: Professor Guosheng YIN, Head of Department of Statistics and Actuarial Science, The University of Hong Kong, and Dr Bin LIU, Assistant Professor of Centre of Statistical Research, School of Statistics, Southwestern University of Finance and Economics (currently Post-doctoral Fellow at HKU). A research team led by Professor Guosheng YIN, Head of Department of Statistics and Actuarial Science, The University of Hong Kong, and Dr Bin LIU, Assistant Professor of Centre of Statistical Research, School of Statistics, Southwestern University of Finance and Economics (currently Post-doctoral Fellow at HKU) has been focusing on the related research and study in order to facilitate the testing for COVID-19 based on chest CT scans. A publicly available online COVID-19 diagnostic system has been developed by the team, and this freely accessible diagnostic system would allow individuals to understand the probability of contracting the disease. The following are the features of the online COVID-19 diagnostic system (https://www.covidct.cn): Fast - Require only chest CT image to show the diagnostic result immediately Accurate - Accuracy: 88%, AUC (performance measurement for binary classification model): 93%, Sensitivity: 86%, Specificity: 90% (See Note 1) Easy to Use - Online web with user-friendly interface Open Source - All codes and data are freely available (https://github.com/xiaoxuegao499/LA-DNN-for-COVID-19-diagnosis) With years of research experience in Biostatistics and Clinical Trials, Professor Guosheng Yin and his team have been actively extending the applications of AI technologies to medical fields in recent years. Meanwhile, the use of chest CT scans for screening suspected cases has been common in the research study of different diseases. “The main reason that we decided to perform the diagnosis based on chest CT scans is because we have accumulated research experiences in the field of Computer Vision. Moreover, there are still many issues with the RT-PCR testing for COVID-19 in terms of false negatives and time lag for diagnosis. The RT-PCR testing usually takes a swab from nose or throat where the coronavirus may gather, and sometimes it requires several tests to make a final confirmation. This would put patients at a great disadvantage, as they cannot be diagnosed in a fast way and be provided with the necessary quarantine and treatment at an early stage.” said Professor Yin. As discovered in radiological research, CT scanning may serve effectively in testing for COVID-19, particularly amongst those with no symptom or minimal symptoms. “This is because the coronavirus will typically first attack the lungs and cause lesions after it enters the body. Therefore, by integrating AI technologies, we can make use of the patients’ chest CT images for early diagnosis. However, since most of the chest CT datasets of COVID-19 patients are not publicly shared, we need to spend much time to search for publicly available samples and tag them,” added Professor Yin. Building this digital platform substantiates again that Radiography and Computer Vision can be perfectly integrated, actualizing the practical use of AI technologies in medical fields. In the early study of CT scanning for COVID-19 diagnosis, the prediction as published in some of the peer researchers’ papers could not achieve the clinical standards. It is believed that, besides a small sample size, it is mainly because the rich annotations associated with the CT images have not been fully utilized. The major difference between this batch of CT images and the traditional medical imaging dataset is that each of the CT samples is collected from a research preprint. In these papers, clinical experts have comprehensively annotated the chest CT images of the COVID-19 patients with detailed lesion descriptions. By leveraging on these text reports from 760 research papers, the research team at HKU has further analyzed and pinpointed five different lesions in association with COVID-19 and each of the confirmed patients is identified with at least one of the five lesions or more. These five lesions are the distinctive features that differentiate COVID-19 from the general pneumonia or other lung diseases. In this regard, the research team at HKU has designed a lesion-attention deep neural network (LA-DNN) model based on the CT images. Whilst the proposed data-driven LA-DNN model focuses on the primary task of binary classification for COVID-19 diagnosis, an auxiliary multi-label learning task is implemented simultaneously to draw the model’s attention to the five lesions of COVID-19. As both tasks are trained synchronously while it shows that the auxiliary task promotes the primary task to focus its attention on the lesion areas and, as a result, the diagnostic accuracy of COVID-19 can be improved drastically. After launching the online COVID-19 diagnostic system, the research team will continue to collect new samples and improve the training model periodically. With regard to the future direction of the applied work, Professor Yin and Dr Liu said, “We hope that medical staff battling with the disease can make use of the system and share their local patients’ image data, in order to initiate collaborative research and accommodate the urgent demands for COVID-19 testing. At the moment, most of the research papers do not share the data and the computer codes, and this does not facilitate knowledge exchange and disease prevention around the globe, yet our online system, data and computer codes are all publicly and freely available for everyone in the world.” Note 1: Sensitivity and specificity are terminologies used in medical diagnosis. Sensitivity, the so-called true-positive rate, measures the percentage of actual positives which are correctly identified. The larger the sensitivity, the better the diagnostic testing for identifying patients. Specificity, the so-called true-false rate, measures the percentage of actual negatives which are correctly identified. Likewise, the larger the specificity, the better the diagnostic testing for confirming negative cases. With regard to COVID-19, we emphasized sensitivity more in order not to misidentify any real COVID-19 patients.

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28 May 2020

Study shows that sea level could rise more than 1m by 2100 if emission targets are not met

An international study found that global mean sea-level rise could exceed 1m by 2100 and 5m by 2300 with unchecked emissions. The study, published in npj Climate and Atmospheric Science, was led by Nanyang Technological University, Singapore, in collaboration with researchers from The University of Hong Kong, Maynooth University (Ireland), Durham University (UK), Rowan University and Tufts University (USA), and the Potsdam Institute for Climate Impact Research (Germany). The study solicited projections of global mean sea-level change under two climate scenarios from more than 100 sea-level experts, who were chosen objectively by identifying a pool of the most active publishers of scientific sea-level studies from the leading publication database. Because projecting sea-level rise comes with many uncertainties, such as glacier and ice cap melting, use of water for irrigation, etc, different modelling approaches can yield significantly different answers as to how much sea levels may change in the future. By surveying leaders in the field, the study offers more broad-based assurance on the ranges of future sea-level rise. In a scenario where warming is limited to 2ºC above pre-industrial levels, experts predicted ~0.5m of rise by 2100 and 0.5–2m by 2300. In a high-emissions scenario with 4.5ºC of warming, experts predicted a correspondingly larger rise of 0.6–1.3m by 2100 and 1.7–5.6m by 2300. These projections exceed those from the Intergovernmental Panel on Climate Change (IPCC). The IPCC increased its sea-level projections by ~60% between its 2007 and 2014 assessment reports, and again in its 2019 Special Report on the Oceans and Cryosphere, given new data on the instability of ice sheets and the fact that sea levels are already rising faster than expected. Nevertheless, even the latest IPCC projections appear to be conservative in the eyes of many sea-level experts. Professor Benjamin Horton, Chair of the Asian School of the Environment at Nanyang Technological University, who led the new survey, said that sea-level rise projections and knowledge of their uncertainties are vital to make informed mitigation and adaptation decisions. “There are numerous sources of global mean sea-level projections which can lead to confusion among policymakers and in decision-making. As an alternative to models of physical processes, sea-level rise may be estimated by surveying experts. This study shows the pressing risks of climate change, and how nations have to act now to secure a future for generations to come,” said Professor Horton. “Sea-level rise is already causing problems on many coastlines with frequent nuisance flooding and more severe storm surges. That is after just 0.2m rise since the late 19th Century,” said Professor Stefan Rahmstorf, Head of Earth System Analysis at the Potsdam Institute. “With increasing ice loss from the major ice sheets, we are about to commit the world to a multi-meter rise that will force us to give up major coastal cities.” Dr Nicole Khan, Assistant Professor of Earth Sciences at The University of Hong Kong, who identified and liaised with experts, as well as developed and conducted the survey, informed that Hong Kong will likely be impacted. “Hong Kong and the Greater Bay Area has considerable population and infrastructure that occur in vulnerable, low-lying areas in Hong Kong that will be increasingly exposed to the effects of sea-level rise and coastal flooding if emissions targets are not met,” said Dr Khan. In response to open-ended questions, the experts surveyed identified the Greenland and Antarctic Ice Sheets as the greatest sources of uncertainty. These ice sheets are an important indicator of climate change and driver of sea-level rise. Satellite-based measurements show the ice sheets are melting at an accelerating rate. However, the surveyed experts also remarked that the magnitude and impacts of sea-level rise can be limited through successful reduction of emissions. “We know that the planet will see additional sea-level rise in the future,” said Dr Andra Garner, Assistant Professor of Environmental Science at Rowan University. “Yet there are stark differences in the amount of sea-level rise experts project for low emissions compared to high emissions futures. This provides a great deal of hope for the future, as well as a strong motivation to act now to avoid the more severe impacts of rising sea levels.”

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27 May 2020

Science student's team Hollo wins 2020 Microsoft Imagine Cup World Champion

Cameron van Breda, who majors in Biotechnology and minor in Science Entrepreneurship, formed the team Hollo with his teammates and won the 2020 Microsoft Imagine Cup World Champion with a mental health companion web application leveraging Azure analytics and AI services to advance youth therapy practices. This is the first team from Hong Kong to have won the World Champion since the launch of the Microsoft Imagine Cup in 2003. Cameron van Breda met his teammates Ajit Krishna Namakkal Raghavendran and Piyush Jha met at HKU. The team noticed that mental health aid was not reaching the younger generations in their communities effectively and envision a future of tech-based, accessible, and comprehensive mental health management tools. With this in mind, Team Hollo developed an interactive mobile app for users and a comprehensive case management dashboard for therapists & NGOs; it also presents a collaborative and scalable mental health platform which aims to cut the heavy cost of mental health care for youth and make support more accessible. Team member Cameron van Breda said, “The experience of mental health is felt by everyone… being able to win Imagine Cup and support the awareness of mental health and be able to work on it with technology is something that’s really needed in the world.” Over 28,000 students from more than 200 countries registered to take part in the Microsoft Imagine Cup and only 10 teams were selected for the Asia Regional Final. Earlier in February this year, Hollo had won the title of World Finalist in the Asia Regional Final with their impactful solution. In winning the World Champion, the team won USD100,000, a mentoring session with Microsoft CEO Satya Nadella, and USD50,000 in Azure grants. The Microsoft Imagine Cup aims to empower students to use their imagination and passion for technology to develop innovative and inclusive solutions that tackle key societal issues. Held online this year due to the pandemic, it is the first time a Hong Kong team took home the Cup, often called the "Olympics of student tech competitions." HKU Chief Innovation Officer Dr Yiwu HE congratulates Team Hollo: “It demonstrated the growing culture of innovation and entrepreneurship on campus among both academics and students here at HKU. We should think not only in terms of pursuing a new idea or concept for discovery, but to facilitate excellent research that results in products that impact the world. we hope HKU will incubate many successful companies with innovative products to help grow the high-tech industry and provide the younger generation with more opportunities in Hong Kong.”

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27 May 2020

HKU mourns the loss of Dr Stanley Ho

The University of Hong Kong community is deeply saddened at the passing of Dr Stanley Ho, our distinguished alumnus. Our thoughts are with his family as we mourn the loss of our loyal friend. Dr Ho studied science at HKU in 1939 until the war broke out in 1941, and was a proud resident of Ricci Hall. He was conferred the Doctor of Social Sciences honoris causa by his alma mater in 1987. For decades the HKU family has been blessed by his loyalty, leadership and generosity. He famously said: "All my life, I never said 'No' to challenges. So when HKU approached me for support, my answer was a straight 'Yes'." From the Flora Ho Sports Centre on Pokfield Road to the Stanley Ho Sports Centre at Sandy Bay; and from his unending support of Ricci Hall and student sports games to his dedicated service as the Founding Chairman and later Honorary Lifetime Chairman of the HKU Foundation for Educational Development and Research, Dr Ho's contributions to the University all bear witness to his passion for education and commitment to future generations. His vision to create a tradition of alumni giving was realised with the internationally acclaimed "Stanley Ho Alumni Challenge" which is now heralded as a milestone in philanthropy. Dr Ho will be fondly remembered for his exceptional devotion and love for the University. He will remain forever part of the HKU legacy.

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26 May 2020

HKU ecologists and international team discovered ongoing and future tropical diversity decline

How can patterns in the marine biodiversity of the past help us to understand how it may change in the future? A recent research by Drs Moriaki Yasuhara and Timothy C Bonebrake (School of Biological Sciences and Swire Institute of Marine Science, The University of Hong Kong) and numerous international collaborators finds that the tropical diversity decline now seen in the ocean is not purely human induced, but nonetheless will worsen considerably if we do not limit anthropogenic climate warming. The research, published in Proceedings of the National Academy of Sciences of the United States of America, used fossil records to reconstruct global oceanic biodiversity patterns of the last ice age (~20,000 years ago) and the pre-industrial period (before 1800s), and used these to build ecological models for projecting global marine biodiversity in the near future (2090s). Using fossil protozoan foraminifera (Images 1, 2) as a "window" to see into past pelagic ecosystems through their rich fossil records, the authors discovered an equatorial "dip" in diversity during the pre-industrial period and projected for the end of this century, but not during the last ice age (Image 3). “Biodiversity is usually high in the tropics and low at the poles. We call this important pattern the ‘latitudinal diversity gradient’. Yet, recent studies have found that global marine biodiversity patterns often show an equatorial 'dip' of diversity. We wanted to explore what caused this, and whether it was a recent pattern,” said lead author Dr Moriaki Yasuhara. The modern decline of tropical diversity likely started during post-ice-age warming around 15,000 years ago. However, the magnitude of decline is projected to be amplified by anthropogenic warming. By the end of the 21st century, tropical diversity may decrease to levels not seen for millions of years if our future aligns with the "business-as-usual" CO2 emission scenario. “By using fossil records we discovered that the diversity ‘dip’ in equatorial regions of the ocean is caused by species distribution shifts driven by post-ice-age ocean warming," continued co-lead author Dr Chih-Lin Wei, Associate Professor at Institute of Oceanography, National Taiwan University. The pelagic ocean covers the vast majority of Earth's surface and is the largest ecosystem on Earth (Images 4, 5). It is home to planktons that play a key role in food chain, top predators and economically important species that are increasingly under threat from climate change. "These clear links between warming and reduced tropical biodiversity mean that by the end of this century, oceanic diversity at the equator may dip to a level unprecedented in human history,” co-author Dr Derek P Tittensor, Associate Professor at Dalhousie University, concluded. About the journal paper Citation: Moriaki Yasuhara, Chih-Lin Wei, Michal Kucera, Mark J. Costello, Derek P. Tittensor, Wolfgang Kiessling, Timothy C. Bonebrake, Clay Tabor, Ran Feng, Andrés Baselga, Kerstin Kretschmer, Buntarou Kusumoto, and Yasuhiro Kubota (2020) Past and future decline of tropical pelagic biodiversity. Proceedings of the National Academy of Sciences of the United States of America. Link of journal paper: http://www.eurekalert.org/s/pio/pnas Image 1: A living planktonic foraminifera, Globigerinoides sacculifer. Photo credit: Katsunori Kimoto. Image 2: Scanning electron microscopy image of a planktonic foraminifera species, Globigerinella adamsi. Photo credit: Briony Mamo. Image 3: Biodiversity patterns with latitudes in three different time periods. Note the equatorial "dip" in the pre-industrial time (green) and 2090s (red), but not in the last ice age (blue). Image 4: An example of pelagic ocean ecosystem 1. Photo by Max Gotts on Unsplash Image 5: An example of pelagic ocean ecosystem 2. Photo by Jet Kim on Unsplash

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25 May 2020

Brilliant “BISME” Bonaza Benefits Bright HKU students via many new prestigious MSc Scholarships in the field of Space Science

To celebrate the upcoming launch of the NJU-HKU No.1 satellite and their MoU with HKU Laboratory for Space Research, the famous Beijing Institute of Space Mechanics and Electricity (BISME) confirmed it was making available at least 300,000RMB annually to establish a minimum of six scholarships at The University of Hong Kong (HKU) for the exciting new Taught Postgraduate Master of Science (MSc) programme in Space Science hosted by the Physics department beginning in September 2020. Up to 6 scholarships (50,000RMB each) shall be awarded annually to students entering the Master of Science in the field of Space Science programme based on academic excellence and academic potential. Students with financial hardship will also be given priority in considering 4 of these scholarships. On top of this there is a further elite scholarship programme of 100,000RMB for approval of any number of outstanding joint projects undertaken by the MSc students within the BISME-HKU Laboratory for Space Research (LSR) . Professor Quentin Parker, the MSc programme director and LSR director said “BISME is a key, strategically vital partner of the LSR at HKU. They have been the lead institute involved in the design and manufacture of our Lobster-eye X-ray telescope. This is due for launch in late July 2020 as the “NJU-HKU No.1 satellite” with the main science mission to look for clues to the origin of dark matter.” Fan Bin (deputy director of BISME) said “I believe that the programme is a timely one and will be helpful to better prepare students. I strongly support this Taught Postgraduate MSc programme in Space Science and hope it can provide a steady stream of talent resources for Space Science research.” “BISME have been a truly excellent partner for the LSR at HKU and we look forward to many years of fruitful collaboration for this first HKU satellite and indeed several others. These scholarships also demonstrate the high value BISME is placing on our new MSc in Space Science in the support of bright young minds entering this exciting and elite programme which is the first of its kind in HK SAR and indeed the entire Greater Bay Area. Their confidence in us and their investment in young minds through this generous scholarship programme is a tremendous example of co-operation and mutual benefit for now and the future, ” added Professor Parker. Dr Lee George Lam, Chairman of Cybeport where the LSR is located said "This new programme is going to open up a new channel for STEM students as well as digital tech-savvy professionals to embark on an exciting career in data-driven innovation fields relevant to the fast-emerging Space Economy. I believe that this programme will complement and bring out the untapped potential of our younger generation and inspire and prepare them well for the Space Economy." Finally, BISME are also offering up to 10 annual internship posts at BISME for HKU Space Science MSc students over the summer with strong prospects for future employment opportunities. MSc in the field of Space Science Department of Physics Beijing Institute of Space Mechanics and Electricity (BISME) Laboratory for Space Research (LSR)

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24 May 2020

HKU marine ecologists reveal larvicidal oil for mosquito control threatens coastal marine life and pollutes sea environment

Application of larvicidal oil (LO) to stagnant waters is the most common practice in Hong Kong to prevent mosquito-borne diseases and protect human health. The Hong Kong SAR Government regularly applies LO to tree holes, ponds, marshy areas and construction sites as a mosquito control measure. However, the oil will eventually make its way into the coastal marine environment due to rainfall and surface runoff. In 2016, former Legislative Council member Mr. Yung-Kan Wong, who represented the agriculture and fisheries sector, invited a team from the School of Biological Sciences and the Swire Institute of Marine Science of the University of Hong Kong (HKU) to investigate fish kills and occasional instances of oil pollution in Shing Mun River and Tolo Harbour, which he had noticed for years and suspected a possible cause was the large quantity of LO being discharged to the sea. In that year alone, local consumption of LO was high at 131,461 litres, according to Food and Environmental Hygiene Department (FEHD) figures. Under the supervision of Professor Kenneth Leung Mei Yee, PhD student Miss Katie Yeung Wan Yee collected water samples at 15 coastal sites from east to west over Hong Kong waters (Image 1) during the summer of 2016 and 2017 to analyse the content of LO. The toxicity of LO was tested with five different marine species (Image 2) which are widely used as model species for laboratory toxicity tests. The team concluded that LO is toxic to marine organisms. Elevated levels of LO were commonly detected in Hong Kong’s coastal seawater, posing moderate-to-high ecological risks to marine organisms in 9 out of 15 coastal sites (i.e., 60%) over Hong Kong waters. It is the world’s first comprehensive assessment of toxicity and ecological risk posed by larvicidal oil. The findings have recently been published in the international journal Marine Pollution Bulletin. In the study, the team analysed the larvicidal oil purchased from the Government’s supplier and found a composition similar to petroleum with a mixture of aliphatic hydrocarbons. Petroleum could lead to the death of fishes and birds due to smothering and toxicity. Of the five marine species tested, waterborne exposure to LO prohibited the growth of the two microalgae (Isochrysis galbana and Chaetoceros gracilis), which are primary producers and the fundamental food source for marine life; and caused mortality to small crustaceans (the brine shrimp and the marine copepod) and the marine medaka fish, which are primary and secondary consumers respectively up the food chain. The microalgae were the most sensitive to LO, with growth inhibition at low concentration of LO. The copepod was comparatively less sensitive to LO. Based on the toxicity results of the study, the safety threshold for LO (PNEC) was determined as 0.29 mg/L, and a hazard quotient (HQ = Measured LO Concentration/PNEC) greater than 1 indicates a potential ecological risk to marine life where adverse effects such as growth inhibition, abnormal development and lethality may occur. Of the nine sites with HQs greater than 1 (red circles in Image 1), four sites, including three in Tolo area recorded high concentrations of LO with HQs > 2 (high risk level), i.e., over two times above the safety threshold. They are Fung Wong Wat (A2) at the outer part of Tolo Channel; and Sam Mun Tsai (A3) and Yim Tin Tsai (A4) inside Tolo Harbour. The other site with high HQ > 2 is Stanley Bay (southern water of Hong Kong Island) (A9). Sites showing an HQ > 1 (medium risk level) include Sai Keng (A1) in Tolo area, Cyberport (A7), Aberdeen (A8), Sai Kung (A13) and Tuen Mun (A14). The six sites with HQ < 1 are Yung Shue O (A5; Tolo area), Sham Shui Kok (A6; Lantau Island), Yuen Long (A12: New Territories) and three sites in Kowloon (i.e., Kwun Tong (A10), Lai Chi Kok (A11) and Tsuen Wan (A15). Professor Kenneth Leung believed that the higher concentrations of LO in general found in Tolo area is probably due to the hydrological conditions in the area. Given that Tolo Harbour is a semi-enclosed body of water, there is a relatively slow water current and low water exchange rate, leading to accumulation of pollutants in Tolo Harbour and Channel. He said: “Our findings confirmed the suspicion of Mr Wong. It is evident that larvicidal oil is toxic to marine organisms. In particular, the oil’s concentrations were found to exceed the safety limit in four out of five sites in Tolo area, its potential ecological risk cannot be ignored. In the coastal environments with moderate-to-high ecological risks of LO, the primary production from marine algae may be inhibited while larvae and juvenile of marine organisms like fishes and crustaceans may experience sub-lethal toxic effects, potentially leading to reduction in their growth, reproduction and survival.” “It is important to ensure its concentration is below the safety limit of 0.29 mg/L in our coastal waters. To do so, the use of the oil should be optimised so as to reduce its negative environmental impact,” added Professor Leung. Miss Katie Yeung remarked: “Our results call for replacing larvicidal oil with a more sustainable and environmentally friendly biocide with a view to minimising the impact to the marine environment. The government could also explore other means to control mosquito larvae such as the use of biological larvicide (e.g. Bacillus thuringiensis) in aquatic environments.” Research background and findings Dengue fever, malaria, yellow fever and Zika are all transmitted to human by mosquitoes which are regarded as one of the deadliest animals in the world. According to World Health Organization, malaria alone globally caused 480,000 deaths in 2015, and all mosquito-borne diseases jointly caused millions of deaths every year (https://www.who.int/neglected_diseases/vector_ecology/mosquito-borne-diseases/en/). In Hong Kong, application of larvicidal oil (LO) to stagnant waters is the most common practice to prevent mosquito-borne diseases and protect human health. In the study, the levels of LO in the seawater samples were quantified using GC-MS (Image 3). Based on the results of the toxicity of LO, a predicted no-effect concentration (PNEC) was determined using the species sensitivity distribution approach. For each study site, ecological risk of LO to marine life was assessed by determining a hazard quotient (HQ = Measured Concentration/PNEC); when the HQ is greater than 1, there is ecological risk to marine life. Concentrations of LO in different coastal seawater samples (Images 3 - 4) Sites with HQ > 1 (i.e., concentration greater than the effect threshold at 0.29 mg/L): Tolo Harbour and Channel Area [HQs: 1.603-2.294]: Sai Keng (A1), Fung Wong Wat (A2), Sam Mun Tsai (A3), and Yim Tin Tsai (A4) [Mean LO concentrations: 0.464-0.664 mg/L] Hong Kong Island [HQs: 1.214-2.158]: Cyberport (A7), Aberdeen (A8) and Stanley (A9) [Mean LO concentrations: 0.351-0.624 mg/L] New Territories [HQs: 1.172-1.479]: Sai Kung (A13), and Tuen Mun (A14) [Mean LO concentrations: 0.339-0.428 mg/L] Sites with HQ < 1 (i.e., concentration lower than the effect threshold at 0.29 mg/L): Yung Shue O (A5; Tolo area), Sham Shui Kok (A6; Lantau Island), Yuen Long (A12: New Territories) and three sites in Kowloon (i.e., Kwun Tong (A10), Lai Chi Kok (A11) and Tsuen Wan (A15)) [Mean LO concentrations: 0.076-0.242; HQs: 0.261-0.837] Results of the toxicity tests Five marine species studied are widely used as model species for laboratory toxicity tests. Their trophic position and toxicity endpoint to LO are given below: Primary producers (microalgae, Isochrysis galbana and Chaetoceros gracilis; median growth inhibition concentration (EC50) of LO at 1.92 and 2.90 mg/L, respectively) Primary consumers (copepod, Tigriopus japonicus; brine shrimp, Artemia franciscana; mortality lethal concentration (LC50) of LO at 8.10 and 3.19 mg/L, respectively) Secondary consumers (medaka fish, Oryzias melastigma; LC50 of LO at 4.39 mg/L) Image 1 Map of Hong Kong indicating the locations (A1 – A15) of collecting seawater samples in this study (A1: Sai Keng; A2: Fung Wong Wat; A3: Sam Mun Tsai; A4: Yim Tin Tsai; A5: Yung Shue O; A6: Sham Shui Kok; A7: Cyberport; A8: Aberdeen; A9: Stanley; A10: Kwun Tong; A11: Lai Chi Kok; A12: Yuen Long; A13: Sai Kung; A14: Tuen Mun; A15: Tsuen Wan). Red circles indicate sites with the hazardous quotient (HQ) > 1, whereas Blue circles indicate sites with the HQ < 1. Image 2 The five test marine organisms used in this study: (A) the microalga Isochrysis galbana, (B) the microalga Chaetoceros gracilis, (C) the brine shrimp Artemia franciscana, (D) the copepod Tigriopus japonicus and (E) the marine medaka fish Oryzias melastigma. Sources of the pictures: (A) alchetron.com; (B) baralgae.com; (C) joelsartore.com; (D) Seo et al. (2006) Aquatic Toxicology 80: 281-289, and (E) from the HKU team. Image 3 Concentrations of larvicidal oil (mean + SE) in seawater samples collected at each of the 15 sampling coastal locations in Hong Kong during wet season in 2017. The number on each bar shows its mean concentration. The horizontal red line is the PNEC value (i.e., 0.29 mg/L). Image 4 Concentrations of larvicidal oil hazard quotients (HQs) (mean + SE) in seawater samples collected at each of the 15 sampling coastal locations in Hong Kong during wet season in 2017. The HQs were computed based on the measured environmental concentration of the larvicidal oil and its predicted no-effect concentration (PNEC) determined in this study. The number on each bar shows its mean concentration. The horizontal red line is at HQ = 1. Image 5 PhD student Katie Yeung was filling up the bottles with collected seawater in Aberdeen.

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15 May 2020

Metagenomics reveals distinct microbiotypes in the giant clams Tridacna maxima

New research conducted at CRIOBE and ENTROPIE research units, with the collaboration of the Swire institute of Marine Science of The University of Hong Kong, The Cawthron Institute and James Cook University, highlights the impacts of benthic species assemblages on the giant clams Tridacna maxima. The findings were recently published in the journal Microbiome. The researchers explored for the first time the influence of benthic species-assemblages on giant clams health, with or without increasing temperature. To do so, they created artificial benthic assemblages using two coral species (Pocillopora damicornis and Acropora cytherea) and one giant clam species (Tridacna maxima). The results showed that the health status of giant clams depended on the neighbouring species. Moreover, using cutting-edge DNA multiplexing-metabarcoding technology adapted by Dr. Xavier Pochon, the team studied the microbial community of the giant clams. The researchers newly discovered distinct microbiotypes (group of specific bacteria) in the studied T. maxima population, one of which was linked to clam mortality. Giant clams are less studied by scientists, yet they are important members of coral reefs and play numerous ecological roles. They are the largest living bivalves and serve as food for fish and human. Like coral, they contribute to primary production through photosynthesis by hosting unicellular algae. They also host a large community of bacteria as well as animals such as shrimps or crabs. However, all of the 12 currently recognised species are under threat and more than 50% of the wild population are either locally extinct or severely depleted. “For decades we have been focusing on the effect of climate change on single species but this doesn’t reflect what could happen within coral reef as a whole. This is why we decided to explore the effect of neighbouring species on the giant clam. We were extremely surprised to discover that the presence of some corals, particularly Acropora cytherea, led to an acute sensitivity of giant clams to increasing temperature which therefore exhibited a high death rate.” explains Dr. Isis Guibert. Microbiomes are an integral part of multicellular organisms, contributing to their health and physiological performance. The scientists noted that despite a surge of interest in this research focus, very few invertebrate microbiomes have been studied. The microbiome of giant clams is particularly interesting because clams are exposed to an extreme abundance and diversity of microbes through filter feeding. The discovery of specific microbiome structure, detectable from the genus level, is the first description of microbiotypes in invertebrates. “The results of our study suggest that, similarly to humans, genetic factors might drive the microbiotype of a giant clam.” said Dr. Isis Guibert. Interestingly, the clams with compromised health were characterised by a prominence of vibrio and therefore a distinct microbiome. “The relative proportion of Vibrionaceae could be used as an early indicator of clam health in natural populations.” explains Dr.Véronique Berteaux-Lecellier, who supervised the study, “We hypothesise that A. cytherea could secrete metabolites that might have weakened the clams’ defenses against Vibrio infection; future research should explore this possibility.” The findings of this study suggest that the composition of the coral reef benthos, together with increasing water temperatures, could negatively impact the health of giant clams and potentially other reef organisms. Therefore, the findings support the idea that, like terrestrial conservation and restoration, taking account of the entire benthic assemblages should be the goal of marine conservation strategies. The open-access study, led by Dr. Veronique Berteaux-Lecellier (CNRS, New-Caledonia) and postdoctoral fellow Dr. Guibert Isis (SWIMS, The University of Hong Kong) was supported by Labex Corail and CNRS fundings. Dr. Guibert Isis also received funding from Sorbonne University. About the journal paper Citation: Guibert I, Lecellier G, Torda G, Pochon X, Berteaux-Lecellier V (2020) Metabarcoding reveals distinct microbiotypes in the giant clam Tridacna maxima. Microbiome https://doi.org/10.1186/s40168-020-00835-8 Short link to the article: https://rdcu.be/b3HJO Video download: https://youtu.be/wZ3Weg4CMKE About the research team Dr. Guibert Isis is a postdoctoral researcher in the Division of Ecology & Biodiversity and Swire Institute of Marine Science at HKU. She spearheaded the work as part of her PhD at Sorbonne University, in the CRIOBE and ENTROPIE research units. Dr. Gael Lecellier is a professor at Paris-Saclay University (UVSQ) at ENTROPIE research unit. Dr. Gergely Torda is a joint Postdoctoral Research Fellow at the ARC Centre of Excellence for Coral Reef Studies of the James Cook University. Dr. Xavier Pochon is a senior researcher at Cawthron institute and the University of Auckland. Dr. Veronique Berteaux-Lecellier is a CNRS researcher at ENTROPIE research unit. 1. Different assemblages of corals and giant clams (Credit: Dr. Lauric Thiault) 2. Dr. Isis Guibert controlling the light intensity for each aquarium. 3. Dr. Isis Guibert looking at a Pocillopora damicornis nubbin (Credit: Dr. Lauric Thiault) 4. Giant clam Tridacna maxima (Credit: Dr. Lauric Thiault) 5 & 6. An Acropora Cytherea nubbin at the coral nursery ground of the InterContinental Moorea Resort & Spa (Moorea, French Polynesia) (Credit: Dr. Isis Guibert) 7. Giant clam Tridacna maxima at the coral nursery ground of the InterContinental Moorea Resort & Spa (Moorea, French Polynesia) (Credit: Dr. Isis Guibert) 8. Dr. Isis Guibert cleaning the nubbins at the coral nursery ground of the InterContinental Moorea Resort & Spa (Moorea, French Polynesia)

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06 May 2020

Four students from Department of Chemistry received Croucher awards for further studies at renowned universities

Four outstanding students from the Department of Chemistry have been awarded postdoctoral research fellowship and scholarships by the Croucher Foundation to pursue doctoral studies and postdoctoral research at world-class universities. Dr Chin Ho LEE is awarded the Croucher Fellowship for Postdoctoral study in the University of California, Berkeley (UC Berkeley). His postdoctoral study will focus on the development of novel synthetic methodology based on gold catalysis. From the perspective of a synthetic chemist, the success of a particular synthesis relies heavily on the availability of suitable synthetic methods and the corresponding substrate scopes. Being able to manipulate the fundamental steps to change the reaction outcome to favour the formation of the desired products is what chemists in the catalysis field are trained for, which is also the reason for Chin Ho to pursue research in catalysis. Together with the knowledge he acquired in PhD study regarding the photophysical properties of the gold complexes, he would like to extend further on the studies on the catalytic aspect of this class of complexes. With availability of supervisor who is one of the pioneers in the field of gold catalysis and state-of-the-art instruments and facilities, Chin Ho wishes to exchange with brilliant minds from all over the world and achieve ground-breaking research. He also hopes that he could learn more regarding catalysis research, as it will be one of his future research directions, and be equipped for taking up an academic position in the future. Three students are awarded the Croucher Scholarship for Doctoral Study: Miss Melanie HALIM will be going to Massachusetts Institute of Technology (MIT) for PhD study. Her research, in light of the ever-growing antimicrobial drug resistance, aims to use chemical strategies to answer fundamental biological questions, ultimately to develop new classes of narrow-spectrum antimicrobials that target multi drug-resistant pathogens. Melanie became interested in chemical biology after an undergraduate Chemistry course, where she learnt about how chemistry can be utilised to investigate biological systems when classic biological methods fell short. A deeper appreciation of how biology works is crucial for effectively modulating it. Being able to control biological systems would be extremely useful in the context of healthcare, environment, industry and other endless possibilities. Her undergraduate research also fostered her interest in understanding the world. Research and learning from inspiring mentors and faculty members gave her a deeper appreciation for the wonder of chemistry. “Chemistry is both magical and powerful. It has clearly and will continue to revolutionise our world,” Melanie expressed. Mr Kevin Wang Yeuk KONG will do his PhD study at the University of Calfornia, Davis (UC Davis). His HKU supervisor was Professor Pauline Chiu from the Department of Chemistry. During his undergraduate study, he conducted research on synthetic methodology ((4+3) cycloaddition) and relevant computational studies on the chemical system. His PhD research will be in theoretical organic chemistry. It was found that Potential Energy Surfaces for chemical systems could process Post-transition state Bifurcations (PTSBs) where reaction pathway is split after the transition state. Such effects affect reaction selectivity as it is now controlled by dynamics on potential energy surface instead of relative energetics of competing transition states. His research aims to propose efficient measures to quantify the effect of PTSBs as well as study such phenomenon in large chemical systems. “The good environment (both in terms of living and research) is a pulling factor for me to go to UC Davis for PhD studies. I believe that it is important to be able to guide experimental studies with theory, for better understanding and to enable more room for rational designs. This project hopefully could help to bridge theoretical results with experiments by addressing one out of many possible reasons that theory does not match well with experimental results,” Kevin said. Mr George Yin Pok WONG will be going to the University of California, Los Angeles (UCLA) for PhD study. He was inspired by recent discoveries on switchable catalysis, which led him to pursue his study in redox-switchable polymerization catalyst for the synthesis of biodegradable multiblock copolymers. By switching between multiple catalytic states through the addition of redox reagents, it would be possible to conveniently form a multiblock copolymer within one pot. After developing this synthetic method, the self-assembly properties of the resulting multiblock copolymers can be subsequently studied, which is important for forming multicomponent micelles with various physical and chemical properties. The development of multicompartment micelles can pave the way for applications in organic drug transportation within aqueous medium. With a desire to conduct research in redox-switchable catalysis, George was attracted to a research group in UCLA who was working in this field. Located in South California, UCLA is a leader in cutting-edge research over a broad range of research fields. With a diverse pool of students from across the world, George will be able to engage with an international community of scientists while pursuing a rigorous postgraduate degree. “I am incredibly grateful for receiving this prestigious scholarship, and I am also very much looking forward to my research pursuit in the upcoming years,” said George.

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15 Apr 2020

HKU study unlocks the secret of corals’ tolerance to climate change: their diet

Researchers at School of Biological Sciences and Swire Institute of Marine Science, The University of Hong Kong have developed a new method for determining what corals eat, and demonstrated that reliance on certain nutritional sources underpins their bleaching susceptibility in warming oceans. The research, published in the prestigious journal Science Advances, solves a conundrum scientists have struggled with for decades; determining the diet of a coral involves measuring how much prey it captures with stinging tentacles as well as how much food is provided by the photosynthetic algae inside their cells. To overcome this challenge, the team, led by Dr Inga Conti-Jerpe, compared the stable isotope “fingerprint” of hundreds of corals collected in Hong Kong to that of their associated algae. The results showed that some corals have isotopic fingerprints that match that of their algae, indicating the two partners share nutrients. Other corals have fingerprints distinct from their algae due to a diet based on the capture and consumption of prey particles in the water. The researchers found that more predatory corals had significantly larger polyps (an individual coral unit – much like an anemone) than corals more dependent on photosynthesis, a previously contentious relationship first proposed in 1974. “We knew that polyp size is a factor that affects the surface area to volume ratio of a coral, a trait that other scientists have observed might be linked to delayed bleaching in the field. We decided to run a warming experiment with our Hong Kong corals to see if their diet accurately predicted how long they could withstand elevated temperatures without bleaching – and it did.” explains Dr Conti-Jerpe. These results have implications for how coral reefs will change as climate change progresses. Corals dependent on photosynthesis bleach faster while predatory corals can withstand warming temperatures longer. “The results of our study help predict which coral species are more likely to survive as oceans warm. Unfortunately, what we found is that the most susceptible species are those that are commonly used in coral reef restoration efforts. To ensure the long-term success of reef rehabilitation, restoration initiatives should shift their focus to bleaching-resistant species.” said Dr David Baker, Associate Professor of School of Biological Sciences and Swire Institute of Marine Science who supervised the study. While predatory nutrition can confer protection from bleaching, the scientists note that given sustained elevated temperatures, all the species in the study eventually bleached. “Capturing a lot of food doesn’t save corals from bleaching,” explains Dr Conti-Jerpe, “it just buys them a little more time – time that they desperately need.” The findings of this study will help scientists, conservationists and policy makers anticipate which corals will disappear first and how this will change reef ecosystems overall, including the services they provide. Stable isotope data are an established tool for investigating diet – they are derived from measuring the different forms of common elements, such as carbon and nitrogen that have the same function biologically but differ ever so slightly in mass. For instance, nitrogen – an essential building block for DNA and protein – comes in a common ‘light’ isotope (14N) and a rare ‘heavy’ isotope (15N). When it comes to diet, animals accumulate 15N if they are sitting higher on the food chain – a carnivore will have more 15N than an herbivore. The corals in this study that had stable isotope values different from that of their algae had more 15N and thus must be more predatory. This research was funded by the Research Grants Council Hong Kong Early Career Scheme (No. 789913) and the Research Grants Council Hong Kong General Research Fund (No. 17100014). About the journal paper Citation: I. E. Conti-Jerpe, P. D. Thompson, C. W. M. Wong, N. L. Oliveira, N. N. Duprey, M. A. Moynihan, D. M. Baker, Trophic strategy and bleaching resistance in reef-building corals. Sci. Adv. 6, eaaz5443 (2020). About the research team Dr Inga Conti-Jerpe spearheaded the work as part of her PhD in the Division of Ecology & Biodiversity and Swire Institute of Marine Science at HKU. She is now a postdoctoral associate in the same department. Dr Phil Thompson is a Research Technician in the Division of Ecology & Biodiversity and Swire Institute of Marine Science at HKU. Mr. Martin Wong contributed to the work during his MPhil degree in the Division of Ecology & Biodiversity and Swire Institute of Marine Science at HKU. Dr Nara Oliveira contributed as a visiting scholar at HKU during her PhD at the Universidade Estadual de Santa Cruz (State University of Santa Cruz, Ilhéus, Brazil). Dr Nicolas Duprey, formally a Postdoctoral Associate at HKU, is currently a Postdoctoral Researcher at the Max Planck Institute for Chemistry (Mainz, Germany). Ms. Molly Moynihan is currently a PhD student at the Earth Observatory of Singapore and Asian School of the Environment at Nanyang Technological University (Singapore). Dr David Baker is an Associate Professor in the School of Biological Sciences and the Swire Institute of Marine Science at The University of Hong Kong (www.thelifeisotopic.com). Dr. Inga Conti-Jerpe, along with other lab members, overlooks corals recovering from bleaching in the coral farm at the Swire Institute of Marine Science, The University of Hong Kong. A close up of a large-polyped coral (Platygyra sp.) The results of this study show that corals with larger polyps and larger mouths are more reliant on energy from food, while corals with smaller polyps and mouths are more reliant on energy from photosynthesis, performed by symbiotic algae that live inside the coral. These differences in diet were then linked to resistance to bleaching under warming temperature: corals with smaller polyp bleached first, while corals with larger polyps took longer to bleach. Coral fragments incubating in a ten-week warming experiment. Some coral species have begun to exhibit bleaching, or a loss of color due to prolonged unusually warm conditions. Video 1: HK coral community Video 2: Porites polyps

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07 Apr 2020

HKU joins International Universities Climate Alliance

Climate research universities unite to accelerate action The University of Hong Kong (HKU) has joined as a member of the International Universities Climate Alliance (IUCA), established to help communicate research insights on the most effective means to meet the unprecedented global challenge of climate change. UNSW Sydney is facilitating the establishment of the Climate Alliance in its first year and to date has invited 40 of the world's leading universities on climate research to join the Alliance. Alliance members are to work together to identify the most effective ways to communicate research-based facts related to climate change to the public. Members will engage in work across climate change science, impact, mitigation strategies and adaptation. Membership comprises a global network of universities, united by their dedication to producing critical climate research. The Climate Alliance benefits from a multi-disciplinary research focusing on the most important research themes to enable greater engagement with policymakers, educators and business leaders looking to apply the latest research findings to accelerate climate action. UNSW Sydney's President and Vice Chancellor Professor Ian Jacobs initiated the creation of the Climate Alliance because of the vital role universities play in advancing the science and solutions in this field, saying "This new Alliance will be at the forefront of the international conversation addressing climate change." Professor Xiang Zhang, President and Vice-Chancellor of the University of Hong Kong, is most delighted to see HKU joining this international alliance. He regards the consortium a long-term capacity-building platform for researchers to exchange information concerning climate change and join hands to formulate solutions for this critical issue. "In HKU, we have very active research in ecology and biodiversity, in which the impacts driven by global warming are one of the key fields of study, in addition to our study on past climates and the phenomenon of climate change today in the field of Earth and planetary science. Our applied work on environmental change will definitely contribute to the research of this area, this is especially important in Southeast Asia where the situation is very acute," said Professor Zhang. "The University of Hong Kong supports the IUCA as a vehicle for promoting research into climate change and its effects. Our climate recognises no borders and so an international effort harnessing the innovative research of our universities to tackle critical issues such as greenhouse gas emissions is needed," said Professor Matthew Evans, Dean of Science and Professor of Ecology, HKU. Notwithstanding current urgencies around the coronavirus pandemic, the members decided not to delay formation of the Alliance due to the pressing and ongoing need to accelerate climate action. Professor Matthew England, academic lead of the UNSW Climate Change Grand Challenge, hopes this alliance will encourage a new era in engagement between researchers and the public; "Worldwide interest to act on climate change is strong but the pace of action has been far too slow. The Alliance aims to accelerate the global response by being a leading voice for scientifically based mitigation and adaptation strategies. More information about the Climate Alliance can be found on www.universitiesforclimate.org. Video on HKU joins International Universities Climate Alliance

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01 Apr 2020

Distinguished Visiting Professor Dr John Cherry has won the 2020 Stockholm Water Prize

Distinguished Visiting Professor Dr John Cherry from Department of Earth Sciences has won the 2020 Stockholm Water Prize – the first groundwater expert receiving this honour. Dr Cherry is named the Laureate for discoveries that have revolutionised our understanding of groundwater vulnerability. Being a world-renowned hydrogeologist and a leading authority on the threats to groundwater from contamination, Dr Cherry is the creator of the academic field contaminant hydrogeology who has changed the scientific paradigms of groundwater research. His research has raised awareness of how groundwater contamination is growing across the world and has led to new and more efficient methods to tackle the problem. The Stockholm International Water Prize Nominating Committee said, “with the Stockholm Water Prize, John Cherry is recognised for his contributions to science, education, practice and for translating his well-earned stature into a passionate and highly effective advocacy for groundwater science to inform current and future policies, laws and collective deliberations that governments must establish to protect water, our most essential and yet most imperilled resource.” Contaminant hydrogeology studies how chemicals and waste leaches into the groundwater. A geological engineer by training, Dr Cherry has pioneered in-depth systematic approaches, including measurement tools and deep insights into groundwater transport processes. Through highly collaborative field experiments, he has developed new ways to monitor, control and clean up contaminated groundwater. Stockholm International Water Institute’s (SIWI) Executive Director Torgny Holmgren commented, “Dr Cherry has made us aware of how much we depend on groundwater and that it is all too often threatened by contamination. We are very grateful for his invaluable contributions in helping us understand how we can protect the world’s groundwater from the threats it faces”. More about Stockholm Water Prize The Stockholm Water Prize is an international water award presented annually since 1991. For 30 years, the world’s most prestigious water award, the Stockholm Water Prize, has honoured women, men and organizations for extraordinary water-related achievements. Stockholm Water Prize is awarded by SIWI in cooperation with the Royal Swedish Academy of Sciences and presented by the Swedish King H.M King Carl XVI Gustaf, the official patron of the Prize.

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The Theme-based Research Team (4th from the right: Prof. X.Y. Li, the leader of this project; 1st from the right: Prof. Kenneth Leung)

29 Mar 2020

HKU researchers develop novel wastewater treatment process to effectively remove health hazardous chemical contaminants

Globally, there is a growing concern regarding the presence of trace emerging contaminants such as retinoids and oestrogenic endocrine disrupting chemicals (EDCs) in aquatic environments. Retinoids such as retinoic acids and their metabolites, which are the derivatives of vitamin A, can cause abnormal morphological development in amphibians, fish, and snails at elevated levels. Oestrogenic EDCs like alkylphenols and bisphenol A are environmental oestrogens that can induce feminization of male fish and abnormal development in aquatic organisms. Sewage effluents are a significant source for the continuous input of these contaminants into the aquatic environment. High levels of these chemical contaminants are commonly found in sewage effluents discharged from conventional sewage treatment plants (STPs). An interdisciplinary team led by the University of Hong Kong (HKU) has developed a novel wastewater treatment system that can effectively remove conventional pollutants, and recover valuable resources such as phosphorus and organic materials (i.e., carbon fibres and volatile organic acids). This novel system combines chemically enhanced primary sedimentation (CEPS) of sewage with acidogenic fermentation of sludge in tandem (Image 1). A series of laboratory experiments were conducted to prove that this novel system can effectively remove trace emerging chemical contaminants from wastewater and is more cost effective compared with conventional wastewater treatment systems. The results of this study have been recently published in Water Research and Environment International. Moreover, in collaboration with the Nanshan Sewage Treatment Plant in Shenzhen, a pilot wastewater treatment system adopting the novel treatment process has been under construction in Shenzhen since 2019. It will come into operation and testing by this summer if the COVID-19 outbreak subsides (Image 2). Background In the past few years, Professor Xiao-Yan Li of the Department of Civil Engineering who led the interdisciplinary research project, has been collaborating with Professor Kenneth Leung from HKU School of Biological Sciences and the Swire Institute of Marine Science to examine the levels and removal efficiencies of retinoids and oestrogenic EDCs from wastewater by the novel wastewater treatment process developed by the research team, and to compare that with the conventional STPs. The research team first examined the levels and removal efficiencies of retinoids and oestrogenic EDCs in Shatin, Stanley and Stonecutters Island STPs in Hong Kong by collecting wastewater and sludge samples from different stages of the treatment process, and analyzing the samples for retinoids and oestrogenic EDCs using liquid chromatography with tandem mass spectrometry (LC-MS/MS). Secondly, a series of laboratory experiments were conducted using a small-scale pilot plant of the novel wastewater treatment process. Samples of wastewater and sludge were taken for the chemical analysis using the protocols developed by Professor Leung’s team. Key Findings The results indicated that the three STPs can only remove an average of 57% of retinoids (range: 41-82%) and an average of 54% of oestrogenic EDCs (range: 31-79%) from wastewater influents (this work was published in Environment International). Using the novel treatment system operated under laboratory conditions, the CEPS process alone was demonstrated to be 16 - 19% more effective in removing retinoids and EDCs than the conventional STPs. 65 - 80% of retinoids and 72 – 73% of EDCs can be removed from the CEPS process (Image 3). After acidogenic fermentation of the CEPS sludge, 50 – 58% of retinoids and 47 – 50% of EDCs were further removed from the supernatants of sludge (this work has been recently published in Water Research). Compared to the conventional STPs, the novel treatment system integrating CEPS with acidogenic fermentation of sludge is comparatively more efficient in removing emerging chemical contaminants from wastewater, and hence could reduce their environmental impacts. In terms of cost effectiveness, the CEPS process has been shown, by other studies, to be more cost-effective than the conventional wastewater treatment process. For instance, the cost of CEPS for wastewater treatment is less than a half of that of the secondary wastewater treatment (i.e., activated sludge process). On one hand, acidogenic fermentation of CEPS sludge can further reduce the treatment cost by recovering organic carbon and phosphate resources from the sludge as the harvested organic carbon and phosphate can be utilized to produce carbon fibers and fertilizers respectively. On the other hand, the acidogenic fermentation of CEPS sludge can provide additional removal of pollutants. The novel treatment process, therefore, offers win-win outcomes. The Way Forward Professor Li, who led the study, said: “When the pilot wastewater treatment system in Shenzhen comes into operation and testing, we hope to demonstrate that this innovative technology will use less energy, generate cleaner effluent and recover more useful materials from the sludge.” Professor Leung said, “We are very pleased to gather evidence for supporting our hypothesis that our novel sewage treatment system can effectively remove the emerging chemical contaminants. With the scaled-up pilot plant in Shenzhen, we will further investigate the removal efficiency of other classes of common pollutants by this novel treatment system.” Regarding its potential application in Hong Kong, Professor Li added, “Our system can be easily retrofitted onto the existing STPs in Hong Kong, like add-on units. For instance, the pilot system will be connected to the existing Nanshan STP in Shenzhen to test its performance. If successful, this will pave the way for advancing wastewater treatment in China and beyond.” This innovative research is funded by Theme-based Research Scheme of Research Grants Council of the Hong Kong SAR. The published articles: Zhou G.J., Lin L., Li X.Y., Leung K.M.Y. 2020. Removal of emerging contaminants from wastewater during chemically enhanced primary sedimentation and acidogenic sludge fermentation. Water Research 175: 115646. Link to the article: https://www.sciencedirect.com/science/article/pii/S0043135420301822 Zhou G.J., Li X.Y., Leung K.M.Y. 2019. Retinoids and oestrogenic endocrine disrupting chemicals in saline sewage treatment plants: Removal efficiencies and ecological risks to marine organisms. Environment International 127:103-113. Link to the article: https://www.sciencedirect.com/science/article/pii/S0160412018327570 Image 1: The novel wastewater treatment system developed by the Theme-based research team led by HKU: Fe-based CEPS with side-stream sludge acidogenesis in relation to the conventional wastewater treatment process. Image 2: The HKU research team’s pilot wastewater treatment plant adopting the novel treatment process under construction in Shenzhen, including the control system, a CEPS tank, an acidogenic fermenter and a moving bed biofilm reactor (MBBR) and carriers. Image 3: The novel wastewater treatment process and removal of emerging contaminants during this process. Image 4: Prof. X.Y. Li (Left) and Prof. Kenneth Leung (Right) taking this picture with the HKU Distinguished Visiting Professor John Giesy from Canada.

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27 Mar 2020

Pathway to HKU Science Series - Live lectures on ZOOM

Two live lectures were delivered via ZOOM by Dr George AKOM and Dr Evan PICKETT on March 27, 2020. Around 270 secondary school students joined the lectures, interacting and learnt from our teachers. Missed the lectures? Here comes the recap and the video: Lecture abstract: 1. Science, Technology and Us - by Dr George AKOM (Lecturer of Faculty of Science) Scientific principles are widely applied to address social issues around us. Scientific knowledge, therefore, is important not only to scientists but to the community. In this talk, we will examine a common compound (chemical) and try to understand how the science behind a common reaction (behaviour) of this compound can be applied to affect our lives in a dramatic way. 2. Animal Voices: What can we learn when we listen to nature? - by Dr Evan PICKETT (Lecturer of Faculty of Science) Animals make sounds for a variety of reasons: to communicate, to warn family of nearby predators, to attract mates. In this talk, we will explore the world of animal communication, what we learn from this chatter and how new technologies allows us to better understand our animal cousins.

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Professor Che Chi Ming receives First Class Award of 2019 Shenzhen Science and Technology Prize from the Shenzhen Science and Technology Innovation Commission (SZSTI)

22 Mar 2020

HKU chemical scientist Professor Che Chi Ming receives First Class Award of 2019 Shenzhen Science and Technology Prize

Professor Che Chi Ming Professor Che Chi Ming, Chair Professor and Zhou Guangzhao Professorship in Natural Sciences at the Department of Chemistry of Faculty of Science, the University of Hong Kong (HKU) has received the First Class Award of 2019 Shenzhen Science and Technology Prize from the Shenzhen Science and Technology Innovation Commission (SZSTIC). Professor Che specialises in synthesis of inorganic and organic chemistry, inorganic and metal organic photochemistry, photocatalysis and bioinorganic medicine, and has significant achievements in the studies of high-valent metal ligand multiple bond complex, inorganic and metal organic light emitting materials, photo-induced electrons and atom transfer reaction, as well as asymmetric olefin epoxidation. Professor Che thanks his research team members including Dr Cheng Gang, Dr To Wai Pong, Dr Lok Chun Nam and Dr Zou Taotao for their dedicated hard work to make the research a success. Professor Che has made innovative discoveries in inorganic photochemistry, electron transfer in multinuclear compounds and atom transfer chemistry. In particular, his outstanding contribution to the study in reactive metal-ligand multiple bonded complexes won him the First Class prize of the State Natural Science Award in 2007. He is the first Hong Kong scientist to have received the honour. The Shenzhen Science and Technology Prize was established in accordance with the Shenzhen Science and Technology Prize Incentives and related implementing rules. It is seen as the important window for the scientific and technological development in Shenzhen, which provides the essential motivation for the realisation of innovative breakthroughs in the city. Professor Che is the first HKU scholar to receive the award. Professor Che was elected to the Chinese Academy of Sciences as academician in 1995, the US National Academy of Sciences as foreign associate in 2013, the Hong Kong Academy of Sciences as founding member and vice president in 2015. Professor Che is now the Director of the Synthetic Chemistry State Key Laboratory, HKU-CAS Joint Laboratory on New Materials and Shanghai-Hong Kong Joint Laboratory in Chemical Synthesis. He also serves the editorial board for Chemical Review and other internationally recognised academic journals.

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With elevated temperatures during a marine heatwave this cardinalfish species (Cheilodipterus quinquelineatus) shows the least changes in gene expression and appears to be more tolerant.

20 Mar 2020

HKU marine biologist and international team unveil impacts of heatwave on reef fishes

A coral bommie filled with a variety of coral reef fish species with differential effects with increased sea temperatures during marine heatwaves. The marine heatwave of 2016 was one of longest and hottest thermal anomalies recorded on the Great Barrier Reef in Australia, influencing multiple species of marine ectotherms, including coral reef fishes. Dr Celia Schunter from School of Biological Sciences and the Swire Institute of Marine Science (SWIMS), The University of Hong Kong (HKU) and a team of international scientists conducted a study attempting to understand the molecular response of five species to the 2016 heatwave conditions that killed a third of the Great Barrier Reef corals. This is the world-first study tracking how wild fish populations respond to a severe marine heatwave. The results of the study were published in the journal Science Advances. Marine heatwaves (MHWs) are elevated extreme temperatures in the oceans for an extended period of time, similar to an atmospheric heatwave. These elevated temperatures can have a significant impact on marine life, possibly pushing the thermal limits of many organisms. With the frequency and intensity of heatwaves predicted to increase in the future, this could have greater impacts on the performance of ectotherms, when compared to slight thermal increments over years or decades. “To understand the challenges fish face under such conditions we used a molecular approach to evaluate how acute warming events directly affect reef fish communities in nature,” said Dr Celia Schunter. “We chose to work with five different species which are commonly found on the reef to be able to understand differences in reactions among fish species with different life histories to get a broader overview of the reaction and impact.” “Our study shows that reef fishes are directly affected by heatwaves, but their responses vary greatly among species,” said co-author Associate Professor Jodie Rummer from the ARC Centre of Excellence for Coral Reef Studies at James Cook University (Coral CoE at JCU). Dr Rummer was part of the international team that studied changes in the expression of thousands of different genes in five species of coral reef fish, collected at different points before, during and after the 2016 heatwave. “Changes in gene expression can tell us how an animal responds physiologically to an environmental shock, such as a heatwave,” said Dr Celia Schunter from HKU School of Biological Sciences and SWIMS, one of the lead authors in the study. “We measured RNA levels in livers in the fish. This can control when proteins are made and in what amount, and these proteins dictate how the cells of the body function. We saw many genes change expression levels across the timepoints of a heatwave revealing important functions such as cellular stress response and changes in metabolic functions.” Through these genetic analyses, the team identified species-specific physiological responses to the heightened temperatures. “Fast water warming causes an increase of the metabolic demands in fishes, which are similar to what happens to an athlete doing intense exercises. When water temperature increases, fishes have a higher demand for energy and oxygen, which leaves a signal that is measurable with genetic techniques. This higher energy demand at warming can affect their reproduction, swimming and development, and that is why it is important to understand the response to warming.” said Dr Moisés A Bernal, co-author of the study from Auburn University. Interestingly, “these patterns of gene expression also changed with the duration of the heatwave,” said Dr Rummer. “This suggests that the physiological mechanisms the fish use to cope with the warmer waters changed as the heatwave progressed. The results suggest fish populations are influenced by both the intensity of a heatwave and how long it lasts.” This signals potential long-term consequences for the health of fish populations as extreme heat events increase in frequency, duration and magnitude under human-induced climate change. At a species level, Dr Rummer says the responses varied in intensity. Some fish struggled less than others. “The spiny damselfish responded strongly to the warmer conditions, with changes in the expression of thousands of genes, suggesting it is particularly sensitive to heatwaves. Other species appear to be more tolerant, with fewer changes in gene expression.” said Dr Rummer. Two of the five studies species studied can also be found in waters around Hong Kong and Southern China as well as many more closely related fish species providing also some context for possible effects for waters around Hong Kong. The study provides a possible approach for predicting which fish species are most at risk under repeated heatwave conditions, said another co-author Professor Timothy Ravasi, from the Marine Climate Change Unit at the Okinawa Institute of Science and Technology Graduate University (OIST). “This has ramifications for policy makers and for the fishing industry, because not all species will be equally affected. We need to screen a large number of species to predict which will be sensitive and which will be more tolerant to warming waters and heatwaves.” “Over time, the fish may adapt to rising temperatures, or even migrate to cooler waters,” Professor Ravasi said. “But these heatwaves are happening now, and it’s necessary to understand and consider the immediate consequences.” In 2015 the South China Sea experienced a heatwave of a similar magnitude than the heatwave on the Great Barrier Reef studied here. The coastal waters of Hong Kong and the South China Sea are predicted to experience more frequent and intense marine heatwave events as seen on the global scale. It is now clear that these extreme events can have far-reaching effects on marine fishes, but also economic implications on aquaculture and fishing industries. Dr Celia Schunter urges the need for more research into the impacts of such events in the marine waters of Hong Kong to avert the potential collapse in the marine ecosystem and the industries relying on it. The paper: ‘Species-specific molecular responses of wild coral reef fishes during a marine heatwave.’ in Science Advances by Moisés A Bernal, Celia Schunter, Robert Lehmann, Damien J Lightfoot, Bridie J M Allan, Heather D Veilleux, Jodie L Rummer, Philip L Munday and Timothy Ravasi. Link of journal paper: https://advances.sciencemag.org/content/6/12/eaay3423 For more information about Dr Celia Schunter’s research, please visit: www.celiaschunter.com/

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13 Mar 2020

HKU scientists find high concentrations of toxic phenyltin compounds in local Chinese white dolphins and finless porpoises

For years Professor Kenneth Leung Mei Yee from the HKU School of Biological Sciences and the Swire Institute of Marine Science and his research team, have been dedicated to the monitoring of toxic substances tribuyltin (TBT) and triphenyltin (TPT) compounds in our marine environment. Globally, organotin compounds such as tribuyltin (TBT) and triphenyltin (TPT) have been widely used as antifouling agents on ship hulls and submerged mariculture facilities over the past decades. Hence, they are often detected in seawater, sediment and biota samples collected from coastal marine environments of urbanised coastal cities worldwide. At very low concentrations, these compounds can cause endocrine disruption or even death in marine organisms. The International Maritime Organisation (IMO) of the United Nations has implemented a global ban on the use of organotin compounds on the hull of sea-going vessels since 2008. Together with their collaborators, Professor Leung's research team discovered that despite a decline of TBT concentration in our marine environment in recent years, the levels of TPT contamination remained serious with an increasing trend. In addition to TPT contamination in seafood, the team's recent research has also confirmed the occurrence of biomagnification of TPT compounds along the marine food chain, resulting in very high concentrations of TPT in two top predators, the Chinese white dolphin and the finless porpoises. This is the first study in the world to confirm the trophic magnification of TPT in food webs of cetacean species, and the findings were recently published in Environment International. Background TBT and TPT are highly toxic biocides which can cause growth inhibition to marine algae and mortality to many marine invertebrates and fishes at 1-50 μg/L*. At very low concentrations (1-10 ng/L**), these compounds can cause endocrine disruption in marine organisms such as growth retardation and shell thickening in oysters, and abnormal development of male sex organs on females of gastropods. TBT and TPT accumulate along the food chain in larger organisms such as fish, and may have an adverse effect on health when consumed by humans. Professor Kenneth Leung and his research team have been monitoring organotin pollution in the marine environment of Hong Kong since 2004. They discovered that TPT contamination remained serious with an increasing trend. TPT had been found in our seafood and in some case, their concentrations (e.g. those in tonguefishes) exceeded the food safety limit for human consumption. In 2017, the Government of the Hong Kong Special Administrative Region finally established a new legislation (Cap. 413, section 3) to support the IMO's global ban of using organotin compounds on vessels, and enhance the control of their release. Methodology In order to fully understand the extent of the contamination, Professor Leung and his team have recently completed a follow-up research in collaboration with Xiamen University and the State Key Laboratory of Pokfulam Road, Hong Kong Tel: (852) 3917 2683 Fax: (852) 2858 4620 E-mail: science@hku.hk Website: https://www.scifac.hku.hk/ Marine Pollution, to investigate the extent of TPT contamination in marine food webs in Hong Kong, and verify whether TPT and its degradation products (i.e., mono- and di-phenyltin; MPT and DPT) can be biomagnified through the food chain, leading to very high concentrations in local Chinese white dolphins (Sousa chinensis) and finless porpoises (Neophocaena phocaenoides). The Chinese white dolphins prefer the inner estuary of the Pearl River Delta, while the porpoises have a greater home range from the southwest to the southeast waters of Hong Kong. Between 2015 and 2017, the study team obtained samples of stranded dolphins and porpoises from the Ocean Park Conservation Fund Hong Kong and collected samples of marine molluscs, crustaceans and fishes from waters at the northwest (i.e., inner estuary) and southwest (i.e., outer estuary) of Lantau Island, respectively. Muscle tissues of all biota samples were analysed for MPT, DPT and TPT using gas chromatography-mass spectrometry, and used for determination of trophic levels using a stable isotope ratio mass spectrometer. Research findings Research findings showed that TPT was the predominant phenyltin compound in the marine mammals, indicating that contamination is an on-going issue. High concentrations of TPT were recorded in the muscle tissue of the Chinese white dolphins and the finless porpoises, with an average of 1,893.8 ng/g w. w. and 1,477.6 ng/g w. w. recorded respectively, even higher than the highest concentration of TPT ever reported in marine mammals the false killer whale worldwide (the false killer whale in Japan with 649 ng/g w. w.[1]). The highest concentration of TPT detected in an adult Chinese white dolphin in this study (3,476.6 ng/g w. w.) was five times higher than that of the false killer whale. At elevated concentrations, TPT can lead to sublethal adverse effects to the immune, nervous, cardiovascular and reproductive systems of mammals, resulting in a negative impact on the population fitness of these local dolphins and porpoises in the Pearl River Delta. Alarmingly, this study also found that the highest TPT concentration in a juvenile finless porpoise (3,455.6 ng/g w. w.) was ten times higher than the highest value (310 ng/g w. w.) recorded in the same species collected from Hong Kong in 2003[2], indicating a worsening situation of TPT contamination. Based on the results of stable isotope and chemical analyses, tissue concentrations of both DPT and TPT significantly increased with increasing trophic level of marine organisms in the food web of the Chinese white dolphins (i.e., inner estuary) while only TPT tissue concentration showed a positive relationship with the trophic level of the biota in the food web of the finless porpoises. For the Chinese white dolphins, trophic magnification factors (TMF) of DPT and TPT were found to be 6.03-11.48 and 2.45-3.39, respectively. For the finless porpoises, the TMF of TPT was found to be 2.51-3.47. When a TMF is greater than 1, it indicates that the chemical compound can be biomagnified through the marine food chain. The results of the study suggest that high trophic organisms including humans are likely to be vulnerable to the exposure of DPT and TPT compounds via dietary intake due to the high trophic magnification potential of these chemicals. Therefore, environmental and human health risks of these compounds should be assessed with consideration of their biomagnification potentials along the food chain. Regarding ways to reduce the health risk of TPT exposure, Professor Leung said, "The public should avoid and minimise the consumption of very large fishes such as sharks and Reeve's croakers, and also benthic fish species such as the flathead and tongue sole fishes, as they probably contain high concentrations of TPT and other persistent organic pollutants in their tissues. Instead, they can consume crustaceans (e.g. shrimps and crabs), shellfishes (e.g. mussels, clams and oysters), and small fishes as an effective way to reduce the intake of TPT and other chemical contaminants." Dr James Lam Chung Wah, an environmental toxicologist and Assistant Professor at the Department of Science and Environmental Studies of the Education University of Hong Kong, who was not involved in the study, commented, "This interesting and impactful study led by HKU provided solid evidence of such a significant biomagnification of TPT along the marine food chain of marine mammals. Their results also highlight the greater impact of TPT on top predators in the sea and in humans through seafood consumption." He also added, "To improve the current situation of organotin contamination, we must reduce their use and release at the source. Around the world, every government needs to play a part in strengthening the regulation and control of the use of toxic chemicals (like TPT compounds) in order to minimise their release into the environment." *1 μg/L is like putting 2.5 g of sugar grains in a standard Olympic-size swimming pool (2,500,000L) **1 ng/L is like putting 4 tiny grains (a grain = 0.00065 g) of sugar in a standard Olympic-size swimming pool Cited References: [1] Harino et al. 2007. Accumulation of organotin compounds in tissues and organs of stranded whales along the coasts of Thailand. Arch. Environ. Contam. Toxicol. 53: 119-125. [2] Nakayama et al. 2009. Temporal and spatial trends of organotin contamination in the livers of finless porpoises (Neophocaena phocaenoides) and their association with parasitic infection status. Sci. Total Environ. 407: 6173-6178. The paper: “Occurrence and trophic magnification profile of triphenyltin compounds in marine mammals and their corresponding food webs”, Environment International (link to the article: https://www.sciencedirect.com/science/article/pii/S0160412019332635)

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13 Mar 2020

Dr Jason Ali achieved unique research quadruple – symbolising interdisciplinary research accomplishment

Dr Jason Ali, Associate Professor of Department of Earth Sciences, achieved a unique research quadruple. He has landed first/correspondence author papers in the frontline journals of four of the Burlington House's learned societies: Geological Society of London (Geology), Royal Astronomical Society (Astronomy and Geophysics), Society of Antiquaries (History and Pre-history) and the Linnean Society (Biology), with his research of redrawing global map of land life. The famous Victorian biologist, Alfred Russel Wallace (1823–1913), spent much of his time looking at how and why land animals were distributed around the planet. He divided the Earth into six continental-scale bio-realms. In the Indonesian island chain he placed the boundary between the Australasian and Asian animal suites – to the east the marsupials and monotremes of Australia. The divide, which soon after became known as the “Wallace Line”, has since been recognised as one of Earth’s most significant biogeographical barriers. However, newly published research led by Dr Jason Ali, together with his colleagues Professor Jonathan Aitchison (University of Queensland) and Professor Shai Meiri (University of Tel Aviv), adds a dramatic twist to the story. Researching the geological development of Australia’s Christmas Island, which lies 1,100 km to the west of the Wallace Line, they discovered that the bulk of its land-mammal and land-reptile species are in fact “Australian”. “Initially, we were interested in establishing when the Christmas Island atoll re-emerged from the depths of the Indian Ocean, which was around 5 million years ago, as that was the instant when lifeforms could begin colonising the landmass. What we had not anticipated was that most of the animal species on Christmas Island have their origins on the eastern side of the Wallace Line. As such, it represents a huge anomaly. The only logical solution is to redraw the Wallace Line to accommodate this finding,” Dr Ali elaborated. Publication of the work marks an impressive accomplishment. Its appearance in the Biological Journal of the Linnean Society achieves a unique quadruple of interdisciplinary research, in the fields of archaeology-history, geology, geophysics, and biology. Dr Ali is now the lead-author of papers in four of the frontline journals of the learned societies that are housed at Burlington House, London (Linnean Society, Geological Society, Royal Astronomical Society, and Society of Antiquaries). Such achievement is unique as only a few people, including Charles Darwin, had done the “Double”; and Dr Ali managed to achieve the first “Triple” twenty years ago. Pulling off the ‘Quadruple’, is very special as no one else is close to matching it. Dr Ali express that “my feeling is that if you are inquisitive and motivated, you can investigate many interesting things and phenomena. You should not be mentally bound to the specialty area you trained in as a young academic. You need to be intellectually receptive and willing to put in the hard-yards”. Research paper “Redrawing Wallace’s Line based on the fauna of Christmas Island, eastern Indian Ocean” on Biological Journal of the Linnean Society

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10 Mar 2020

HKU Paleontologists Discovered a Solid Evidence of Formerly Elusive Abrupt Sea-level Jump

Meltwater pulses (MWPs) known as abrupt sea-level rise due to injection of melt water are of particular interests to scientists to investigate the interactions between climatic, oceanic and glacial systems. Eustatic sea-level rise will inevitably affect cities especially those on coastal plains of low elevation like Hong Kong. A recent study published in Quaternary Science Reviews presented evidence of abrupt sea level change between 11,300–11,000 years ago in the Arctic Ocean. The study was conducted by Ms Skye Yunshu Tian, PhD student of School of Biological Sciences and Swire Institute of Marine Science, the University of Hong Kong (HKU) during her undergraduate final year project in the Ecology & Biodiversity Major, solving the puzzle of second largest meltwater pulse (labelled as “MWP-1B” next to the largest and already well understood MWP-1A). During the last deglaciation, melting of large ice sheets in the Northern hemisphere had contributed to profound global sea level changes. However, even the second largest MWP-1B is not well understood. Its timing and magnitude remain actively debated due to the lack of clear evidence not only from tropical areas recording near-eustatic sea-level change, but also from high-latitude areas where the ice sheets melted. The research study, led by Ms Tian under the supervision of Dr Moriaki Yasuhara, Associate Professor of School of Biological Sciences, HKU and Dr Yuanyuan Hong, Postdoctoral Fellow of School of Biological Sciences, HKU, and in collaboration with scientists in HKU and UiT The Arctic University of Norway, discovered a robust evidence of formerly elusive abrupt sea-level jump event during the climatic warming from the last ice age to the current climate state. The study presented evidence of abrupt sea level change between 11,300–11,000 years ago of 40m–80m in Svalbard, the Arctic Ocean. High time-resolution fossil records indicate a sudden temperature rise due to the incursion of warm Atlantic waters and consequent melting of the covering ice sheets. Because of the rebound of formerly suppressed lands underneath great ice load, the sedimentary environment changed from a bathyal setting (having deep-sea species shown in Image 1) to an upper-middle neritic setting (having shallow-marine species shown in Image 2) at the study sites. This is the first solid evidence of relative sea-level change of MWP-1B discovered in ice-proximal areas. The research group used fossil Ostracoda preserved in two marine sediment cores as a model organism to quantitatively reconstruct the water depth changes in Svalbard in the past 14,000 years, as this small (usually <1 mm) aquatic crustacean is very sensitive to water conditions. Faunal turnovers also reveal temperature and salinity changes associated with the MWP-1B. All ostracode shells in the samples were picked and identified under the microscope, and then the faunal assemblage and species diversity were computed. More than 5,000 specimens and 50 species were recorded in two sediment cores from Storfjorden, Svalbard, where the environment is sensitive to both Arctic and North Atlantic influences. Abrupt sea level event caused by ice-sheet melting is crucial for us to understand Earth climate system influencing and being influenced by glacial conditions. "Future eustatic sea-level rise may be discontinuous and abrupt, and different from smooth and continuous global warming projected, known as "hockey stick" curve. This has serious implications for our society, especially for cities on coastal plains of low elevation, like our Great Bay area on the Pearl River Delta. Even small sea-level rise can substantially increase damages from typhoons, for example," Dr Yasuhara said. The paper ‘Deglacial–Holocene Svalbard paleoceanography and evidence of Melt Water Pulse 1B” is published in Quaternary Science Reviews. URL: https://www.sciencedirect.com/science/article/pii/S0277379119309485?dgcid=coauthor Image 1: Scanning Electron Microscopy image of typical deep-sea (bathyal) ostracod species from the study sites. Image 2: Scanning Electron Microscopy image of typical shallow-marine (neritic) ostracod species from the study sites.

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Retail eel products found in local grocers, convenient stores and supermarkets.

05 Mar 2020

Endangered species on supermarket shelves: HKU’s Conservation Forensics Lab reveals the surprising prevalence of European Eel in Hong Kong’s food supply

Researchers studying samples of juvenile eels Far far away, behind the word mountains, far from the countries Vokalia and Consonantia, there live the blind texts. Separated they live in Bookmarksgrove right at the coast of the Semantics, a large language ocean. A small river named Duden flows by their place and supplies it with the necessary regelialia. It is a paradisematic country, in which roasted parts of sentences fly into your mouth. Even the all-powerful Pointing has no control about the blind texts it is an almost unorthographic life One day however a small line of blind text by the name of Lorem Ipsum decided to leave for the far World of Grammar. The Big Oxmox advised her not to do so, because there were thousands of bad Commas, wild Question Marks and devious Semikoli, but the Little Blind Text didn’t listen. She packed her seven versalia, put her initial into the belt and made herself on the way. When she reached the first hills of the Italic Mountains, she had a last view back on the skyline of her hometown Bookmarksgrove, the headline of Alphabet Village and the subline of her own road, the Line Lane. Pityful a rethoric question ran over her cheek, then Imagine purchasing products from your local grocer, only to find out that those products are comprised of critically endangered species! That's what a team from the University of Hong Kong, Division of Ecology and Biodiversity has recently discovered on Hong Kong supermarket shelves. A team led by Dr David Baker from the University's Conservation Forensics laboratory, has recently published the results from an investigation into European eel products on sale in Hong Kong supermarkets. The study, published in Science Advances, found that nearly 50% of retail eel products, ranging from fillets to snack items from grocers and convenience stores, contained a critically endangered species of fish. According to the IUCN, The European eel (Anguilla anguilla) is at risk of extinction. For this reason, trade in European eels and their food product derivatives is subject to international regulation under the Convention for the International Trade of Endangered Species (CITES). CITES is meant to ensure that permits are required for their import and export in an effort to regulate trade and foster conservation. Eel, extremely popular in East Asia and particularly Japan, has traditionally been fished from East Asian populations of the Japanese eel (Anguilla japonica). However, overexploitation due to growing demand from Mainland China and a combination of threats ranging from rising ocean temperatures, parasites, and dammed rivers have led to dramatic declines in eel populations. This is true not only for European and Japanese species, but also for their American and Indo-Pacific relatives. To satisfy demand for eel in East Asia, juvenile eels (known as glass eels) are caught while swimming upstream in their native range spanning Europe and North Africa, and smuggled to Asia to be raised to maturity. To date, captive breeding of eels has not been economically viable; wild-caught glass eels are thus used to "seed" eel farms. In recent years the illegal trade has been highlighted by a number of high-profile investigations and increasing prosecutions. "The illegal export of glass eels from Europe to Asia has now been recognised as one of the world's greatest wildlife crimes and Europol has estimated the scale of over 300 million eels (2018 data) annually. The next step is to investigate the global consumer markets to identify where these trafficked eels are eventually consumed. The numbers from Hong Kong are very alarming and reflect the huge amounts of European eels that are being farmed in Asia. It is now up to individual countries to investigate the scale of European eels entering their national food chains illegally." -Florian Stein, Sustainable Eel Group The international trade in glass eels is incredibly lucrative. One kilogram of glass eels can contain up to 3,500 individuals and has been recorded selling for over HKD$50,000 on the black market. This highly profitable trade has attracted the attention of international criminal syndicates, who smuggle glass eels in suitcases from Europe to Asia for resale. In their juvenile stages, eels are extremely difficult to identify to the species level. The two most common cousins of the endangered European eel (the Japanese and American eel) are not listed in CITES, therefore no permit is required for their trade. Because of the challenges in visual identification, endangered European eels can be laundered along with their legally traded relatives. Already, the existence of Europe-Asia smuggling routes has been documented, but the ultimate destination of the smuggled eels remained elusive. Originally conceived as an undergraduate project looking at seafood mislabeling, the investigation into European eel took off when students noticed a surprising amount of European eel present in supermarket products. "The eel project is the most exciting thing I have done during my undergraduate study in HKU. I once thought research was only for postgraduates and professors, but it turns out I, even as a student, was able to do meaningful research that actually made an impact in illegal trading. This has made me more determined to continue work in environmental fields." -Haze Chung, Year 4 Undergraduate Researcher The study covered a wide range of Hong Kong supermarkets and convenience stores across all districts. Surprisingly, almost 50% of the eel products surveyed were determined to be European eel. The results from this study suggested that large scale smuggling networks trafficking European eels are interwoven with local supplier chains, resulting in endangered species ending up on supermarket shelves, totally unbeknownst to consumers. For the paper in Science Advances: https://advances.sciencemag.org/content/6/10/eaayS0317

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04 Mar 2020

HKU Science excels in QS World University Rankings by Subject 2020

According to the QS World University Rankings by Subject 2020, HKU Science continues to excel in a wide array of science disciplines. The rankings symbolisess 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: Life Sciences & Medicine: #50 Natural Sciences: #49 Biological Sciences: #51 Chemistry: #42 Earth & Marine Sciences: #50 Environmental Sciences: #51 Materials Science: #51 Mathematics: #43 Physics & Astronomy: #51 Statistics & Operational Research #50

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A crab resting on the mangrove in Ting Kok, Tai Po. (Photo credit: The Swire Institute of Marine Science and School of Biological Sciences, The University of Hong Kong)

25 Feb 2020

A team of international mangrove forest experts suggesting optimistic cause for global mangrove conservation

More than a decade ago, a team of mangrove experts warned that mangrove forests were being lost faster than almost any other ecosystem, including coral reefs and tropical rainforests. Nonetheless, the situations are getting better now. An international team of 22 researchers led by National University Singapore (NUS) from 24 institutes including Dr Stefano Cannicci from The Swire Institute of Marine Science and School of Biological Sciences, the University of Hong Kong (HKU), found that there is now cause for optimism, with the global loss rate of mangrove forests less alarming than previously suggested. After studying various earlier presented works, the team found that globally, mangrove loss rates have reduced by almost an order of magnitude between the late 20th and early 21st century - from what was previously estimated at 1% to 3% per year, to about 0.3% to 0.6%. The drastic drop in the loss rate is attributed greatly to the successful mangrove conservation efforts. This heightens conservation optimism amongst broader projections of environmental decline. A commentary summarising the team's findings was published in the scientific journal Current Biology. This international effort was the result of the Fifth International Mangrove Macrobenthos and Management conference (MMM5), the world's largest mangrove conference which was held for the first time in Singapore last year. "The team deduced that the reduction in mangrove global loss rates has resulted from improved monitoring and data access, changing industrial practices, expanded management and protection, increased focus on rehabilitation, and stronger recognition of the ecosystem services provided by mangroves," explained Associate Professor Daniel Friess from the Department of Geography of NUS. Dr Cannicci from HKU said: "I am very proud of being one of the academics who warned about world mangrove loss a decade ago, since I think that the paper published at that time contributed to a turn the tide on mangrove degradation. There are still dangers and we still have to manage and preserve mangroves worldwide, but the perception about their importance for humankind has definitely changed. In particular, a recent survey held in Hong Kong by me showed that mangroves area in Hong Kong has increased in the last 20 years and that these ecosystems are huge reservoirs of crab, mollusca and insect diversity." Dr Cannicci said the data discussed in the present paper strongly support the need to implement good practices in conservations, also for Hong Kong mangroves. He remarked: "Although small and limited in size, HK mangroves harbour a magnificent diversity of plant and animal species. Eight species of trees, 53 species of crabs and 42 species of snails have been recorded in these forests, which is more than is known for the mangrove forests of the whole African continent." After years of degradation, mangroves in Hong Kong now cover about 350 ha (Hong Kong Island has an area of about 7859 ha). Distributed across about 40 forests, they represent the largest remaining mangrove patch within the Pearl River Delta, with the largest one distributed along the coast of Deep Bay. There are also many small, but pristine patches in the North East New territories and a small one located on Hong Kong Island. Positive change in mangrove conservation Mangrove forests occur along the shorelines of more than 100 countries and are incredibly important as they offer numerous critical benefits to people, including protection from coastal erosion and storm as well as cyclone damage, natural filters for pollution and sediment, carbon sequestration which helps to mitigate climate change, and provide millions of people with products such as fuelwood, construction materials and fisheries resources, since mangroves act as nursing grounds for many coastal fishes. "There is strong evidence that positive conservation change is occurring. Mangrove conservation has gained substantial momentum, with greater public and government awareness leading to investment and on-the-ground action. However, despite recent mangrove conservation successes, tempered optimism is necessary, as conservation gains are not evenly spread, nor guaranteed into the future," cautioned Associate Professor Friess. Mangroves under threat in emerging deforestation frontiers The team found that mangroves continue to be threatened by aquaculture, agriculture and urban development across the world, particularly for new deforestation frontiers that are emerging throughout parts of Southeast Asia and West Africa. Southeast Asia is a traditional hot spot of mangrove deforestation as mangroves are cut down to make space for aquaculture ponds, cleared for rice paddy cultivation, and reclaimed for industrial and port development. "Emerging deforestation frontiers need to be addressed early. Improved environmental governance and increased public intervention can help secure positive conservation outcomes in these locations. We need to take decisive steps to improve the success and scale of mangrove rehabilitation, and increase the resilience of mangroves to sea-level rise to maintain the current progress in mangrove conservation," commented Dr Candy Feller from the Smithsonian Environmental Research Center, one of the contributors to the study. Maintaining current progress in mangrove conservation Even mangrove rehabilitation is lauded as a method to offset historical as well as ongoing losses and can yield long-term ecosystem service provision, the team found that successful rehabilitation is still a challenge to achieve at scale. Current mangrove rehabilitation projects around the world can fail because key ecological thresholds and rehabilitation best practices are ignored - for instance, planting in low-intertidal locations that are not suitable for mangrove growth and using non-native species that can quickly become invasive, which gives rise to myriad ecological impacts on the intertidal zone. "Ensuring that mangrove conservation gains are not short-lived will require continued research, policy attention, and renewed efforts to improve the success of mangrove rehabilitation at a scale that will be ecologically impactful," said Dr Erik Yando, Research Fellow at the NUS Department of Geography. To ensure that the mangrove conservation gains are not short-lived, continued research, policy attention, and renewed efforts to improve the success of mangrove rehabilitation at a scale are required. The international team will continue to monitor mangrove deforestation and conduct studies to assess the benefits and values of mangroves in Southeast Asia. The article: “Mangroves give cause for conservation optimism, for now” in Current Biology To view the article For more information about Dr Stefano Cannicci’s research, please visit: https://www.imeco-lab.com/ The international team found now cause for optimism for global mangrove conservation. (Photo credit: The Swire Institute of Marine Science and School of Biological Sciences, The University of Hong Kong)

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24 Feb 2020

HKU Science student's startup being selected as the Asian Champion in the Microsoft Imagine Cup

Congratulations to HKUiDendron Team Hollo for winning the Asian Champion in Microsoft Imagine Cup! Cameron van Breda, studying Biotechnology and Science Entrepreneurship, has established startup Hollo with his teammates Piyush Jha and Natalie Lee, who study computer science and psychology respectively at HKU. Hollo, being a social tech enterprise based in Hong Kong, aims to develop a comprehensive tool for NGOs, therapists, and youth living with mental illness to advance therapy practices using technology such as Big Data and AI. The startup equips youths living with mental illnesses, who cannot capture their experiences consistently, with a smart CBT-compliant companion app; provides low cost self-help and journaling process to aid their own journey. Hollo also equips therapists (and their NGOs), who don’t have consistent, quality patient feedback to aid retentive treatment, with a back-end platform equipped with empirical and actionable findings on their patients; using the data analysis to enhance time efficiency, and construct predictive models. The Microsoft Imagine Cup is designed to inspire students to use their imagination and passion for technology to create innovative solutions that tackle some of the world’s biggest social, environmental, and health challenges. After all, Hollo will be representing Hong Kong in the Seattle Global Final to compete for the Imagine Cup trophy in May! All the best to them! About Hollo About the Microsoft Imagine Cup

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21 Feb 2020

Professor Chi Ming CHE being awarded the Luigi Sacconi Medal 2020

Professor Chi Ming CHE, Zhou Guangzhao Professor in Natural Sciences of Department of Chemistry, was awarded the Luigi Sacconi Medal 2020 for his achievements in Inorganic Chemistry have been of top quality during all his scientific career. The Luigi Sacconi Medal is awarded by The Inorganic Chemistry Division of the Italian Chemical Society and the Luigi Sacconi Foundation every year to a scientist who has obtained outstanding results in Inorganic Chemistry. Congratulations to Professor Che for receiving the honour! More about Professor Che's researchMore about the award

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11 Feb 2020

Congratulations to our teachers for their receiving of the University's awards

Congratulations to our teachers Dr David Li, Dr David Baker and Professor Wai Ki Ching for their receiving of the University's awards, which are to recognise their dedications to research and imparting of research knowledge to students . We are proud of their outstanding achievements. To know more about information about the awardees, plese visit the following websites: Dr David Xiang LI Research Output Prize 2018-19 Dr David BAKER Outstanding Young Researcher Award 2019 Professor Wai Ki CHING Outstanding Research Student Supervisor Award 2019

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Researcher(s) drilling coral under water.

09 Feb 2020

HKU marine ecologists and international team unveils the historical impacts of development on coral reef loss in the South China Sea, suggesting possible coral restoration in Hong Kong

New research led by The University of Hong Kong, Swire Institute of Marine Science in collaboration with Princeton University and the Max Planck Institute for Chemistry highlights the historical impacts of development on coral reef loss in the South China Sea. The findings were recently published in the journal Global Change Biology. Using cutting-edge geochemical techniques pioneered by their Princeton collaborators, the team extracted minute quantities of nitrogen from coral skeletons, which grow in observable layers of growth similar to tree rings. Although more than 99% of the skeleton is calcium carbonate, the coral secretes a protein scaffolding upon which the minerals are attached. In this way, corals can control their calcification which increases in productive summer months and decreases in cool winter months leading to a tell-tale alternation of high and low density bands. Those bands were observed and measured using x-ray equipment at the Ocean Park veterinary hospital. Using coral cores archived at The University of Hong Kong, and spanning research laboratories at HKU, Princeton, and the Max Planck Institute, the team, led by SWIMS postdoctoral fellow Dr Nicolas Duprey extracted skeletal material from each band to reconstruct a nearly 200-year time-series of change in the Pearl River Delta that pre-dated British colonization. The coral – still living as of 2007, had continuously recorded the conditions of its environment during that period of time by utilizing resources from seawater to build new skeleton. Nitrogen, a key component of the protein scaffolding, is one such element derived from the corals diet. Coincidentally, nitrogen also bears tell-tale signs of human disturbance through the increasing prevalence of sewage pollution and a rapidly changing landscape in the Pearl River catchment within Guangdong Province. The well-documented collapse of southern Hong Kong coral communities in the 1980-1990s remained a mystery for the scientific community until now. The authors report that during the coral’s lifespan, the human population within the multi-city megalopolis sky-rocketed some 3,000% to today’s ~100 million people. Modern records showed that especially in the 1980s-1990s, during Hong Kong’s rapid development and the reclamation of Victoria Harbour, water quality deteriorated substantially which coincided with severe losses of local coral reefs, especially in western waters. “The precise detective work that our team has led over the last 5 years allowed us to identify the main culprit of this loss: water quality! This is a very interesting find because often time global warming is pointed out as the cause of coral decline worldwide; we often feel helpless facing this scenario because it involves changing drastically everybody’s lifestyle on the planet to fix the problem. However, in the Pearl River Delta, the threat is different and originates from our poor handling of waste water treatment locally. Paradoxically, this is a good news because it implies that the solution to this problem is in our hands. Indeed, the improvement in waste water treatment in the 2000’s was recorded in our coral skeleton, indicating that these efforts must be continued if we want corals to come back in Hong Kong, ” said lead author Dr Nicolas Duprey. Moreover, the coral skeleton revealed that in that specific timeframe a major anomaly in the nitrogen isotope ratio occurred. This was an indication that the source of nitrogen the coral used to build its skeletal scaffolding became was replaced by pollution. To verify this, the researchers also measured the isotope values from museum specimens held by the Smithsonian Institution and Yale Peabody Museum that were collected in Hong Kong in the 1800s during some of the first global biodiversity expeditions. The open-access study, led by Associate Professor Dr David Baker and SWIMS postdoctoral fellow Dr Nicolas Duprey was funded by the Environment and Conservation Fund. NN Duprey, XT Wang, T Kim, JD Cybulski, HB Vonhof, PJ Crutzen, GH Haug, DM Sigman, A MartínezGarcía, DM Baker (2019) Megacity development and the demise of coastal coral communities: evidence from coral skeleton δ15N records in the Pearl River Estuary. Global Change Biology. To view the paper Figure 1: The urban development on the world's coastlines is a rising threat for coral reefs. (a) The map shows the population density (source: CIESIN, 2017), the world's megacities (source: UN, 2018), coral reefs (source: UNEP‐WCMC, WorldFish Centre, WRI, TNC, 2010), and the world's hotspot of coral biodiversity, the Coral Triangle (Veron et al., 2011). (b) Detail map of the Pearl River Delta region showing the eight major cities composing the megacity and the Hong Kong Special Administrative Region (HKSAR) and their populations. The four sites sampled for this study are indicated with outlined symbols. The coral communities having experienced a major decline are highlighted in color. Maps were made with the geographic information software QGIS (www.qgis.com) Image 3a & b: The museum specimens from the Smithsonian Institution and Yale Peabody Museum that were used for comparison of isotope values of coral skeleton. These specimens were collected in Hong Kong in the 1800s during some of the first global biodiversity expeditions.

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A community of deep-sea animals (Photo credit: Lisa Levin)

05 Feb 2020

HKU marine ecologist and international team identifies areas of top priority for deepsea monitoring and conservation through a survey of world’s leading deep-sea scientists

To classify the most important ecological and biological components of the deep sea, an international team including Professor Roberto Danovaro from Stazione Zoologica Anton Dohrn Napoli, Italy and Dr Moriaki Yasuhara from The Swire Institute of Marine Science (SWIMS) and School of Biological Sciences, The University of Hong Kong (HKU) sent a questionnaire-based survey to the world’s leading deep-sea scientists around the world. They then analysed the responses received from 112 scientists so as to create an expert-led list of priorities covering all aspects of deep-sea monitoring, conservation and management. The results of the survey are presented in a Perspective in the leading journal Nature Ecology & Evolution, identifying key areas on which future conservation and management strategies should be focused. The article highlights priorities for monitoring, including large animals and habitat-forming species like deep-sea corals, and the impact of human activities such as mining on this vulnerable ecosystem. The deep sea (defined here as below 200-metre depth) represents the largest, but least explored, type of environment, or biome, on Earth. It is home to many ecologically rare, unique and unknown species that are increasingly under multiple threats from industrial deep-sea mining, deep-sea fishing, climate change and plastic pollution. The results of the survey indicated that habitat-forming species such as deep-sea corals were considered the most important area for conservation efforts. Large and medium-bodied organisms were considered the top priority for biodiversity monitoring in deep-sea habitats. Other equally significant factors for monitoring the deep-sea environment include habitat degradation and recovery as a measure of ecosystem health, and classification of the food-web structure of deep-sea communities to monitor the functioning of whole ecosystems. Identifying shifts in the depth ranges of different species was also a priority for monitoring responses to climate change. “People tended to think deep sea is immune from human impacts or climate changes but scientific studies have been proving that it is untrue. Indeed, a better and standardised monitoring framework to prepare and manage for future is needed,” said Dr Yasuhara. South China Sea is, of course, not an exemption from the threats. SWIMS is an Asian hub of marine conservation and contributes to global deep-sea issues, for example, through this global collaborative paper and also through the ongoing 2nd World Ocean Assessment led by United Nations. “The results are useful as a guideline for future deep-sea research, conservation and monitoring. The endorsements and adoptions of the proposed deep-sea essential ecological variables by industry, governments and non-governmental organisations would also help guide more sustainable management of oceans,” the authors concluded. Image 1: Fishing line tangled (left back) in a mussel bed at a methane seep off Costa Rica. (Photo credit: Lisa Levin and Schmidt Ocean Institute) The paper: 'Ecological variables for developing a global deep-ocean monitoring and conservation strategy' in Nature Ecology & Evolution by Roberto Danovaro and collaborators including Moriaki Yasuhara. Link to the journal paper

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07 Jan 2020

Professor Vivian Yam being conferred the Foundation Lectureship Award 2019

Professor Vivian YAM (Chemistry) has been conferred the Foundation Lectureship Award 2019 by the Federation of Asian Chemical Societies (FACS) which comprises over 30 chemical societies across Asia. With one Foundation lectureship awarded every two years among many brilliant chemistry academics across Asia, the fellowship is naturally competitive and prestigious. More about Profesor Vivian Yam: Philip Wong Wilson Wong Professor in Chemistry and Energy BSc(Hons), PhD, CSci, CChem, FRSC, BBS, JP Member of the Chinese Academy of Sciences Foreign Associate of the National Academy of Sciences, USA Fellow, TWAS, The World Academy of Sciences Foreign Member of Academia Europaea (MAE) Founding Member, The Hong Kong Academy of Sciences Congratulations for Professor Yam's outstanding achievements!

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HKU receives a large donation of 3D kinematics software for geoscience research

Bird beak revealed by HKU-codeveloped laser imaging Informs early beak form, function, and development

Seven HKU young scientists awarded China's Excellent Young Scientists Fund 2020

HKU receives a large donation of 3D kinematics software for geoscience research

Bird beak revealed by HKU-codeveloped laser imaging Informs early beak form, function, and development

Seven HKU young scientists awarded China's Excellent Young Scientists Fund 2020

A joint team of astronomers including a member of HKU’s Laboratory for Space Research, captured stellar winds in unprecedented detail

Member of HKU’s Laboratory for Space Research Co-discovers the first planet found around white dwarf star

Professor Zheng Xiao GUO elected Member of Academia Europaea

Landmark HKU-led volume on past progress and new frontiers in the study of early birds and their close relatives

Most close relatives of birds neared the potential for powered flight but few crossed its thresholds

HKU architects and marine scientists co-develop novel 3D printed ‘reef tiles’ to repopulate coral communities and conserve biodiversity in Hong Kong

Successful launch of the world’s first soft X-ray satellite with “Lobster-Eye” imaging technology: The Dark Matter Hunter

“Breaking” news! A new idea on how Earth’s outer shell first broke into tectonic plates

New Intensive Major in Biological Sciences for 6901 BSc students

HKU study reveals the hidden fight within corals

Revisiting energy flow in photosynthetic plant cells

HKU-codeveloped automated laser-scanning ‘hunter drone’ seeks out fossils, minerals and biological targets

Professor Vivian W W Yam has been bestowed with the most prestigious Porter Medal 2020

Dimethylsulfoniopropionate concentration in coral reef invertebrates varies according to species assemblages

Quantum Material research connecting physicists in Hong Kong, Beijing and Shanghai Facilitates discovery of better materials that benefit our society

An unexpected heat shock to neurons: HKU scientists and collaborators uncovered a new mechanism for balancing protein stability during neuronal development

Mangroves at risk of collapse if emissions not reduced by 2050, international scientists predict

Statisticians have developed an online diagnostic system with AI technologies based on COVID-19 chest CT dataset for screening suspected cases

Study shows that sea level could rise more than 1m by 2100 if emission targets are not met

Science student's team Hollo wins 2020 Microsoft Imagine Cup World Champion

HKU mourns the loss of Dr Stanley Ho

HKU ecologists and international team discovered ongoing and future tropical diversity decline

Brilliant “BISME” Bonaza Benefits Bright HKU students via many new prestigious MSc Scholarships in the field of Space Science

HKU marine ecologists reveal larvicidal oil for mosquito control threatens coastal marine life and pollutes sea environment

Metagenomics reveals distinct microbiotypes in the giant clams Tridacna maxima

Four students from Department of Chemistry received Croucher awards for further studies at renowned universities

HKU study unlocks the secret of corals’ tolerance to climate change: their diet

HKU joins International Universities Climate Alliance

Distinguished Visiting Professor Dr John Cherry has won the 2020 Stockholm Water Prize

HKU researchers develop novel wastewater treatment process to effectively remove health hazardous chemical contaminants

Pathway to HKU Science Series - Live lectures on ZOOM

HKU chemical scientist Professor Che Chi Ming receives First Class Award of 2019 Shenzhen Science and Technology Prize

HKU marine biologist and international team unveil impacts of heatwave on reef fishes

HKU scientists find high concentrations of toxic phenyltin compounds in local Chinese white dolphins and finless porpoises

Dr Jason Ali achieved unique research quadruple – symbolising interdisciplinary research accomplishment

HKU Paleontologists Discovered a Solid Evidence of Formerly Elusive Abrupt Sea-level Jump

Endangered species on supermarket shelves: HKU’s Conservation Forensics Lab reveals the surprising prevalence of European Eel in Hong Kong’s food supply

HKU Science excels in QS World University Rankings by Subject 2020

A team of international mangrove forest experts suggesting optimistic cause for global mangrove conservation

HKU Science student's startup being selected as the Asian Champion in the Microsoft Imagine Cup

Professor Chi Ming CHE being awarded the Luigi Sacconi Medal 2020

Congratulations to our teachers for their receiving of the University's awards

HKU marine ecologists and international team unveils the historical impacts of development on coral reef loss in the South China Sea, suggesting possible coral restoration in Hong Kong

HKU marine ecologist and international team identifies areas of top priority for deepsea monitoring and conservation through a survey of world’s leading deep-sea scientists

Professor Vivian Yam being conferred the Foundation Lectureship Award 2019