List of Science Talks (2018-19)

ST0017
Early Life on Earth

By Department of Earth Sciences
Level: F.4 – F.6
HKDSE Related Subject(s): Biology and Chemistry

The talk will describe recent findings on how life appeared and evolved during Earth’s early days and how tell-tale signs from some peculiar ancient rocks bear information on Earth’s early environment.

ST0115
Galapagos Evolution "Story" Takes a New Twist

By Department of Earth Sciences
Level: F.4 – F.6
HKDSE Related Subject(s): Biology and Geography

The animals and plants on the Galapagos Islands (eastern equatorial Pacific) provided Charles Darwin with fundamental insights into Natural Selection, the mechanism that is largely responsible for driving biological evolution. New research indicates that the evolutionary pathways of a majority of the land-bound animals on the island chain (racer snakes, leaf-toed geckos, lava lizards and iguanas) have been critically shaped by large-magnitude shifts in sea level over the last 700,000 years. The fluctuations resulted from a combination of climate change and various geodynamic processes. This talk will explain how we now think the Galapagos bio-laboratory "works".

ST0141
The Weird World of Ferns: The Ancient Plants that Revolutionised the Land

By Faculty of Science
Level: F.5 – F.6
HKDSE Related Subject(s): Biology

With more than 250 species in Hong Kong, ferns are a very important part of tropical rainforests. In this talk, you will learn about the amazing diversity of ferns, their weird biology and how to tell apart the ferns of Hong Kong.

ST0050
HKUtopia – a Chemistry-promoted Ideal House for a Better Living

By Department of Chemistry
Level: F.5 – F.6
HKDSE Related Subject(s): Chemistry

The presentation will be based on the Champion-winning project of the 22nd Hong Kong Chemistry Olympiad in 2011. The talk will discuss how state-of-the-art chemistry can make for better living in the foreseeable future with a chemistry-promoted eco-house named HKUtopia. It features self-sustainability, is pollution-free, highly luxurious and is ideal living for the future.

ST0078
Let There be Light: Chemistry of Luminescent Materials

By Department of Chemistry
Level: F.4 – F.6
HKDSE Related Subject(s): Chemistry and Liberal Studies

Converting invisible power into visible light has always fascinated mankind. Light can be generated from a heated object, which is called black body radiation. Emission of light can also be obtained as a result of a chemical/ biochemical reaction or electrical excitation, which is called luminescence. Scientists have harvested the principles of luminescence in various disciplines, such as display technology, forensics, and sensors. In this talk, we will briefly describe the principles of luminescence and the applications of luminescent molecules.

ST0014
Molecules for Liquid Crystal Displays

By Department of Chemistry
Level: F.5 – F.6
HKDSE Related Subject(s): Chemistry

In this talk, the basic working principles for different types of display devices, from the conventional cathode ray tube to the recently developed liquid crystal display (LCD) and light emitting diode (LED), will be presented. The molecules being used in these display devices will be presented. We will also present the trend in display technology for the future.

ST0004
Understanding Cancer

By School of Biomedical Sciences
Level: F.4 – F.6
HKDSE Related Subject(s): Biology

Cancer is a genetic disease caused by alterations in oncogenes and other related genes. This talk will first introduce the ground-breaking discovery of oncogenes that was awarded a Nobel Prize in 1989. How a normal gene might become an oncogene through mutations and the mechanisms will be introduced. Examples will be given to illustrate how our understanding of the function of oncogenes leads to a revolution in the design and development of highly specific and effective anti-cancer drugs that target oncogenes.

ST0067
Understanding Influenza Viruses

By School of Biomedical Sciences
Level: F.4 – F.6
HKDSE Related Subject(s): Biology

Influenza viruses cause thousands of deaths and enormous economic loss every year. In this talk, the life cycle of influenza viruses will be introduced. The speaker will use past examples to illustrate how pandemic influenza viruses arise. Finally, the talk will explain how our knowledge of influenza viruses can help the design and development of vaccines and antivirals. Particularly, new methods to make influenza vaccines will be described.

ST0122
Cryptography: Our Continued Effort to Hide Information from the Others

By Faculty of Science
Level: F.4 – F.6
HKDSE Related Subject(s): Physics and Mathematics

In this talk, we will go through some general principles in making secret codes. We will explore how our coding methods evolve in complexity as we accumulate knowledge in science and mathematics. Finally we will discuss how our understanding of quantum physics suggests a way to devise a theoretically "unbreakable" coding scheme.

 ST0120
Electrifying Bacteria and their Technological Applications

By Faculty of Science
Level: F.4 – F.6
HKDSE Related Subject(s): Physics, Chemistry and Biology

Microorganisms depend on continuous electron flow for the formation of electrochemical gradients that enable the synthesis of adenosine triphosphate (ATP) to sustain key cellular processes. Some anaerobic bacteria are able to transfer electrons extracellularly to insoluble, solid-state electron acceptors such as oxide minerals and synthetic surfaces such as electrodes. In this talk, we will explore how scientists discovered this so-called extracellular electron transfer (EET) ability of some bacteria and how this interesting ability can be employed for practical applications such as energy generation, wastewater treatment, bioremediation and materials synthesis.

ST0133
From Bits to Qubits and from Earth to Space:
An Unbreakable Way to Transmit Secret Information

By Department of Physics
Level: F.4 – F.6
HKDSE Related Subject(s): Physics

Measurement in the quantum world is an active process that could irreversibly change the state of a quantum bit (qubit). That is why quantum information processing is very different from classical information processing that it allows secure communications that relies only on the assumption that quantum physics is correct. This talk gives an overview on quantum cryptography and quantum information processing, highlighting recent advances in the field including the science behind the first ever quantum communication satellite "Micius" launched in China.

ST0132
Solar Energy

By Department of Physics
Level: F.4 – F.6
HKDSE Related Subject(s): Physics

Solar energy that reaches the Earth is several orders of magnitude higher than our energy needs. It is abundant, renewable and a clean source of energy. However, it is not well utilised at present due to high cost of solar cells needed for energy harvesting. In the talk, the speaker will give a brief overview of different solar energy technologies from silicon panels to organic materials. The challenges in reducing the cost and achieving wide scale applications will also be discussed, and a practical demonstration of making a solar cell will be conducted as well.

ST0112
Darwin in the City: Understanding Evolution in an Urban World

By Department of Earth Sciences
Level: F.4 – F.6
HKDSE Related Subject(s): Biology and Geography

We live in an increasingly urbanised world —— more than half of the human population now lives in cities. This talk will discuss how new urban environments change the evolution of urban-dwelling species, from plants to birds to humans. For example, we will discuss why mammals are often bigger in cities, why birds are becoming more and more active at night, and why cities are becoming more and more similar in terms of the species found in them.

ST0110
Noise Annoys: Understanding the Effects of Noise Pollution on Human and non-Human City Dwellers

By Department of Earth Sciences
Level: F.4 – F.6
HKDSE Related Subject(s): Biology and Geography

Cities are noisy environments, and this noise pollution has negative effects on all residents of a city, including humans. In this talk we will explore the greatest contributions to noise pollution in cities, the unique auditory environment that exists in modern cityscapes, and learn how this noise affects both humans and wildlife within the city boundaries.

ST0119
Scientific Health Risk Assessment of Persistent Organic Pollutants at Intensive Electronic Waste Recycling Sites

By School of Biological Sciences
Level: F.5 – F.6
HKDSE Related Subject(s): Biology, Chemistry and Liberal Studies

Electronic waste has become one of the emerging environmental issues to be tackled worldwide. Approximately 54 million tonnes of e-waste were produced in 2012. Despite increasingly strict international regulations and control programmes, a substantial part of e-waste generated in consumer societies is exported to developing countries, where it is often recycled through environmentally harmful methods or dumped in unprotected areas, causing severe environmental and health damage accompanied by a range of socio-cultural problems. In this talk, students will be able to learn the basic principles of conducting scientific health risk assessment of persistent organic pollutants, local and global issues of e-waste and the adverse impacts of primitive e-waste recycling in developing countries.

ST0111
The Anthropocene: Are We Causing the 6^th Mass Extinction Event?

By Department of Earth Sciences
Level: F.4 – F.6
HKDSE Related Subject(s): Biology, Geography and Liberal Studies

As the human population grows, our increasing need for resources leads to a major impact on the environment. In this talk, students will learn about how human activities are changing the processes and cycles of life on Earth and what effects these changes are having upon the Earth.

We will look specifically at the causes of the previous five mass extinction events and discuss whether human activities are causing animals to go extinct at equal rates, potentially leading to the 6^th mass extinction event.

ST0126
You are what you Eat–Food Chemistry for Everyone

By Faculty of Science
Level: F.4
HKDSE Related Subject(s): Biology and Chemistry

In recent years, it has not been uncommon to read news about food contamination by chemicals, be that from human error or natural disaster, in Hong Kong and its neighbourhood countries. The general public may become anxious when it comes to the term "chemical" in food. Indeed, we may fail to understand the nature of a chemical reaction. There is no good or bad in the nature of chemistry. A fine line between the positive and negative impact of chemistry in society exists in the choices we make regarding its application in our daily life. In this talk, students will also have an opportunity to create their own molecular gastronomy.

ST0138

Myths and Truths about Genetically Modified Organisms (GMOs)

By School of Biomedical Sciences
Level: F.4 - F.6
HKDSE Related Subject(s): Biology, Chemistry and Liberal Studies

GMOs are becoming a hot issue around the world. However, there are a lot of myths about their occurrence, production, safety, environmental impacts, etc. This talk aims to clarify some common beliefs about GMOs with scientific concepts and evidences. Different applications of GMOs will also be discussed.

 ST0137
Cosmic Fireworks

By Department of Physics
Level: F.4 – F.6
HKDSE Related Subject(s): Physics

Have you ever wondered where do elements on Earth come from? The heavy metals, including gold, iron, and even calcium in our bones are indeed star dusts released in supernova explosions when massive stars die. This talk introduces these most energetic events in the Universe, which do not only produce heavy elements, but also trigger new stellar formation, and could even have played an important role in the origin of life on Earth.

 ST0118
The Galactic Graveyard and the Ultimate Fate of Our Sun

By Faculty of Science
Level: F.5 - F.6
HKDSE Related Subject(s): Physics

This talk will introduce how stars live and die — sometimes dramatically for the heaviest stars in spectacular supernovae explosions. These cosmic fireballs enrich interstellar space with heavy metals generated in the explosion. This includes elements like gold. The remnant stellar core is now well on the way to becoming a so called white dwarf. These typically have the size of our own earth but with a mass over one half that of our sun. It is so dense that one small teaspoon of a whitedwarves matter would weigh several tons. The ejected glowing embers of these dying sun-like stars present a colourful and impressive array of shapes and forms and are collectively known as planetary nebula. In this talk, this fascinating but brief period in the death of low mass stars will be described.

ST0037
The Sun: Our Nearest Star

By Department of Physics
Level: F.5 - F.6
HKDSE Related Subject(s): Physics

This talk will introduce the properties of and recent observational results regarding the Sun –– our nearest star. The focus is on how astronomers find them out rather than simply a talk on "known facts".

ST0089
Why are Galaxies Strung in Space like Beads on a Spider Web?

By Department of Physics
Level: F.4 – F.6
HKDSE Related Subject(s): Physics

We live in the Milky Way Galaxy, around a star we call the Sun, which is but one of several hundred billion stars in our galaxy. There are many billions of galaxies like our Milky Way Galaxy, and in total many trillions of galaxies, in the Universe. Astronomers have found that the arrangements of galaxies in the sky resemble beads strung along the threads of a spider web, a pattern named Cosmic Web. This talk will show how astronomers measure the distribution of galaxies in the sky, and why a simple consideration of gravity on matter in the Universe produces the Cosmic Web.

 ST0145
Will Human Even Live on Mars?

By Department of Earth Sciences
Level: F.4 – F.6
HKDSE Related Subject(s): Biology, Chemistry and Physics

The first robots were sent into space just over 60 years ago. Since that time, humans have launched many robotic spacecraft into the Soalr System, and some even beyond. Through human missions, we have learned that the space environment is very challenging for the human body and min. But, looking forward the future, it seems inevitable that we will ahve an increasing presence in space. Will humans ever live on the Moon, on Mars or anywhere in space? Are there resources for us to use or mine in space? In fact, who owns property or material in space? Are there laws in space? This talk will touch on some of the history of space flight, a vision for the future, and some of the challenges we will likely face in terms of biology, technology, law and ethics.

ST0129
Ancient Models of the Universe: How Scientific Knowledge is Obtained

By Faculty of Science
Level: F.4 – F.6
HKDSE Related Subject(s): Physics

While early models of the cosmos and the universe may seem laughable to modern humans, they are in fact very useful and elegant for describing the motions of the sun and stars that would have been well-known to even the most uneducated members of ancient societies. This talk will introduce how humanity rejected the intuitive ideas of a flat-Earth fixed in the center of the universe and moved closer to our modern understanding.

ST0128
Conway's Game of Life: Complexity Born from Simplicity

By Faculty of Science
Level: F.4 – F.6
HKDSE Related Subject(s): Mathematics

The rules for Conway’s Game of Life are simple and easily understood. However, there is no limit to the complex behaviour that can be seen to arise from these simple rules. This talk will introduce this important cellular automaton as well as others in order to highlight how the complex and complicated nature we see around us could be born from sets of very simple rules.

ST0140
Calculus: Why should We Care?

By Faculty of Science
Level: F.5 – F.6
HKDSE Related Subject(s): Mathematics

Calculus is a subject that many secondary school students have to take (and dread!), but why we learn it is rarely discussed. From internet search engines to radio waves to modelling how diseases spread, calculus has significantly affected scientific understanding and applications throughout our recent history. We will take a look at some basic calculus concepts and discuss why they were crucial in the development of humankind. Prior understanding beyond secondary school mathematics is not required.

ST0117
Groups and Symmetry

By Department of Mathematics
Level: F.4 – F.6
HKDSE Related Subject(s): Mathematics

This talk will introduce the concept of a group through the study of the mathematics behind the idea of symmetry. As mentioned in the first sentence of the Preface of the book Groups and Symmetry by M A Armstrong: "Numbers measure size, groups measure symmetry ...," a group basically encodes the symmetry features of a geometric object. In this talk, the symmetries of some simple figures as motivation for the abstract mathematical definition of a group will be shown. The relation between groups and rearrangements (permutations) of objects will be shown also.

ST0088
In the World where Angle Sum of Triangle Does Not Equal to 180 Degrees

By Faculty of Science
Level: F.4 – F.6
HKDSE Related Subject(s): Mathematics

Can you imagine that two parallel lines can intersect? Is the sum of the interior angles of a triangle necessarily 180 degrees? If we do not follow the parallel postulate proposed by Euclid in his text Elements, we open the door of non-Euclidean Geometry. Development of non-Euclidean geometries since the 19th century has exerted a profound impact on the development of mathematics, introducing fundamental changes to the concept of space such as Einstein's Relativity.

ST0039
Interesting Things about Interest Rates

By Department of Statistics and Actuarial Science
Level: F.4 – F.6
HKDSE Related Subject(s): Mathematics

This talk will introduce some basic concepts and characteristics about the operation of interest rates. The speaker will also briefly look into the relationships between interest rates and other economic variables.

 ST0090
Is Mathematics Discovered or Invented?

By Faculty of Science
Level: F.4 – F.6
HKDSE Related Subject(s): Mathematics

It has been debated over centuries, whether mathematics already existed in nature and was gradually discovered by human, or if it was simply a human invention. The speaker will provide different examples and let us reflect on this question and look into the nature of mathematics.

ST0101
Misuses of Statistics

By Department of Statistics and Actuarial Science
Level: F.4 – F.6
HKDSE Related Subject(s): Mathematics

Statistics is used everywhere in our daily lives, from research reports and scientific articles to newspaper reports and magazines. Unfortunately, the misuse of statistics, either accidentally or purposely, is very common. This talk will discuss some real life examples on how statistics are misused, and how not to commit and not be misled by these misuses.

ST0144
The Mathematics of Sharing

By Department of Mathematics
Level: F.4 – F.6
HKDSE Related Subject(s): Mathematics

In daily life we often have to allocate resources to different parties. For instance kids may try to share a cake among themselves. When a group of friends ride a taxi home they may try to split the fare. In an election seats are allocated to different parties according to the number of votes. As we try to look for "fair" ways of allocation some interesting mathematical problems arise. In this talk we will try to investigate some of these problems.

ST0116
Probability and Phylogeny

By Department of Mathematics
Level: F.4 – F.6
HKDSE Related Subject(s): Mathematics

As Charles Darwin's theory of evolution became widely accepted in the scientific community, biologists started to discover the history of the evolution of a species. They wanted to answer questions like "what is the closest living organism to a species", "what is their common ancestor, and when did they diverge", etc. However, the evidence is very limited –– most of the common ancestors are extinct and very few of their remains can be found in fossils. This talk will introduce how mathematics is used to find those linkages hidden in the genes.

ST0041
Statistics: The Art of Scientific Reasoning

By Department of Statistics and Actuarial Science
Level: F.4 – F.6
HKDSE Related Subject(s): Mathematics

For over a century statistics has provided scientists, and practitioners alike, with an important tool for data analysis, for reasoning and for drawing inference. This talk will explore the wide range of applications of statistics through real-life examples.

ST0131
The Art of Mathematics: Funs and Applications

By Department of Mathematics
Level: F.4 – F.6
HKDSE Related Subject(s): Mathematics

Mathematics relies on both logic and creativity. Is mathematics an art or a science? For most of us, the essence of mathematics lies in its beauty and its intellectual challenge. In this talk, we will feel the beauty and elegance of mathematics through fun stories and applications.

ST0025
The Wonderful World of 0 and 1

By Department of Mathematics
Level: F.4 – F.6
HKDSE Related Subject(s): Mathematics

The wonderful world of 0 and 1 touches every aspect of our lives. You are probably familiar with the digital world through surfing on the internet with an iPad, making a phone call with Xiaomi Note, or chatting through WeChat, etc. This talk, however, will show you another face of this wonderful world. It turns out that mathematics provides solid underlying principles or different aspects, and nearly all branches in mathematics, such as, algebra, geometry, analysis, and so on, can find their applications in the world.

ST0102
Discovery of the "God Particle"— the Higgs Boson

By Department of Physics
Level: F.4 – F.6
HKDSE Related Subject(s): Physics

From the ancient ideas of Aristotle’s four elements to the concept of atoms, and to the existence of subatomic particles such as electrons, protons, and neutrons, scientists have made significant progress in the understanding of the fundamental structure of matter. The best current framework to explain all the particles and phenomena observed is known as the Standard Model. One of the last missing pieces of the puzzle to the Model, the Higgs boson, was discovered in 2012. This talk will present a brief history of humanity's quest to study the structure of matter, along with a brief description of the Standard Model, and the beautiful experiments that led to the discovery of the Higgs particle at CERN (the European Council for Nuclear Research).

ST0094
Neutrinos — The Ghost Particles that Penetrate Earth

By Department of Physics
Level: F.4 – F.6
HKDSE Related Subject(s): Physics

Neutrinos are one of the tiny fundamental particles that form our universe. They are highly penetrative with millions and millions of them every second passing through our body and even the Earth without being noticed. Because they are so difficult to be detected, neutrinos have been given the nickname of "ghost particles". There are 3 kinds of neutrinos and they can change from one kind to the other through a phenomenon called neutrino oscillation. Recently the Daya Bay Reactor Neutrino Experiment has successfully measured one of the neutrino oscillation parameters called theta-13. This result will enhance our understanding of some of the mysteries of our universe. This talk will introduce the properties of neutrinos and explain how they are measured in the Daya Bay Experiment.

ST0136
Symmetry

ST0134
The Four Nobel Prizes Associated with Neutrinos and Beyond

By Department of Physics
Level: F.4 – F.6
HKDSE Related Subject(s): Physics

Neutrinos are produced by rare nuclear processes such as the beta decay. These particles are very hard to study because they are electrically neutral, almost massless and interact very weakly with all matters. This talk summarises how physicists study the properties of neutrinos in the past 60 years so on by building larger and larger detectors, resulting in four Nobel Prize works so far –– and probably a few more to come! The speaker will also highlight Hong Kong's contribution in some of the recent neutrino physics experiments.

 ST0135
The World of Particles

By Department of Physics
Level: F.4 – F.6
HKDSE Related Subject(s): Physics

Particle physics aims at addressing the most fundamental questions in the universe. It is a worldwide frontier in physics. With the startup of the Large Hadron Collider (LHC) at the CERN lab in 2009, the world's largest and highest-energy particle accelerator, particle physics enters a new phase—the LHC era. Since then, great progress has been achieved. For example, the Higgs particle, was discovered at the LHC in 2012, about half a century after its existence was predicted by theorists. This progress marks a triumph of collaboration between theoretical and experimental particle physicists, and has been named 2012's "Breakthrough of the Year" by science. This talk will introduce how this discovery is made and why it is so important for us to have a deeper understanding of universe.