HKU Bulletin May 2022 (Vol. 23 No. 2)

CONTENTS Bursting Bubbles Crypto Meets the Real World Social Relations and Money Money and the State Money, Markets and the Rise of Modern China Material Values 02 04 06 08 10 12 Bursting Bubbles The Myths, Realities and Future of Money HKU scholars look into our psychological and social relationships with money and money’s role in the Russian Revolution and the emergence of modern China, while giving consideration to the contradictory promises of digital currency. 42 Fighting Back against COVID-19 14 32 02 food for thought all systems go Cover Story Research Teaching and Learning Knowledge Exchange Books 18 Rapid response something to chew on 22 Fighting Back against COVID-19 Rapid Response Sweet Deal for Songbirds Something to Chew on Diamonds Are a Tooth’s Best Friend The Public Knows Best China’s Jumpy Take on Tech Men Win out in Divorce in China All Systems Go Evaporation Revelation The Common Core Turns 10! Leaders of Tomorrow Early Detection to Beat Liver Disease Food for Thought Your Right to Technology Identity Dramas 14 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46

Money is shrouded in two myths – that it is a creation of markets, not the state, and that people use it in rational ways. HKU scholars have been poking holes in these ideas, focussing on our psychological and social relationships with money and money’s role in the Russian Revolution and the emergence of modern China. At the same time, they are giving consideration to the contradictory promises of digital currency, which could both free us from government oversight and empower greater oversight. Bursting Bubbles 03 COVER STORY 02 The University of Hong Kong Bulletin | May 2022

Fiat money, generally speaking, is money that is issued and backed by states who promise to uphold its value. But that has not stopped people from imagining a world where currencies are ‘denationalised’. About 50 years ago, when economist Friedrich Hayek speculated on this possibility, it was impossible to test out on a massive scale as the technology was not ready. Today, the advent of cryptocurrencies has changed all that. Companies and individuals can now create their own online ‘tokens’ or currencies that can be used to make transactions as sufficient users recognise the value. This has given rise to utopian ideals of an economy that is independent, decentralised and run by its users. Dr Yang You, Assistant Professor of the HKU Business School, has been studying different forms of cryptocurrencies, but he is not convinced they will change the world as proponents envision. “Technology can secure digital property rights, however, it cannot resolve everything. You still need to rely on a trusted party to provide information that connects the digital footnote to the real world, and you still need some centralised power or authority to enforce that,”he said. Nonetheless, there are ways in which the crypto world is starting to change our ideas of money and how it is controlled. A distinguishing feature of digital currency is that it can be programmed, which has attracted deep interest from central banks, he said. China, for instance, is interested in the traceability function which would make it possible to understand household behaviour or business practices better. Governments could also program digital money to be spent only on specified items, such as programming COVID-19 relief funds to be spent only on food and other necessities. “A key feature of conventional fiat money is that it is memory-less – you don’t know who owned it before or how they used it,”Dr You said. “Generally, there are a lot of possibilities to re-engineer fiat money now.” Online demand That would put a lot of information in government hands, but governments are not the only ones with the potential to develop digital currencies. There are signs of an emerging cyber economy where tokens that act like currencies could emerge from payment systems within platforms, such as the Steam gaming platform and YouTube. Viewers would use the tokens to enjoy activities online but have no physical product as such delivered. Big players like Facebook and Alibaba could also develop a currency for their users. Dr You sees more development in this area as young people spend substantial time with their phones and engage with their friends on social media rather than offline hangouts. “The time spent online can potentially create a real demand – I don’t see that as a fake thing,”he said – though it is more likely these currencies would be confined to use on specific platforms. His research has shown there are high issuance costs and pricing constraints to creating tokens that can be tradeable elsewhere. Bitcoin and cryptocurrencies Dr You also looks at digital currencies created beyond governments or companies. Bitcoin is the most famous example, but it is problematic because while it is created by ‘miners’ who supply the hardware and electricity to keep the network going, it is very slow and costly to use. “I think of Bitcoin kind of as a souvenir, beautiful but not very. The value comes from the limited supply, and the price only depends on consensus,” he said – unlike fiat currencies backed by governments, or even company-created tokens backed through the services they provide. He sees more potential in the cryptocurrency Ethereum, which can embed contracts and other applications into its blockchain. These ‘smart contracts’ secure transactions digitally and require each party to set up a digital wallet through which the contract payment is executed automatically on the due date. The hitch is that people are still needed to validate the conditions of the contract – in Ethereum’s case, miners are paid a ‘gas fee’ for their service, which is somewhat similar to a lawyer’s, but cheaper and less complicated. NFTs (non-fungible tokens) are another form of contracted digital currency which can track owners and, in the case of artworks, enable creators to earn a profit from their works. However, smart contracts currently can only handle very basic transactions. “There are a lot of possibilities, but I don’t want to overstate how powerful these can be because the real world is much more complicated and sophisticated than anything that can be coded in these contracts,”he said. As cryptocurrencies evolve, Dr You does not see them diverging from the real world. “They will merge, in a sense, because people spend so much time in the cyber world now and they care about their digital assets there,”he said. “The conventional money issuers, the governments, are trying to figure out what they can do to enhance their currencies, whether to recognise digital assets as real assets and how to collaborate with the cyber society.” CRYPTO MEETS THE REAL WORLD DR YANG YOU They will merge, in a sense, because people spend so much time in the cyber world now and they care about their digital assets there. Digital currencies promise contradictory things – from giving authorities the power to trace people’s spending to supporting a cyber economy that is free from government oversight. Dr Yang You’s research suggests that eluding the existing world order may be a pipe dream, but there is ample room for the cyber and the real to converge. COVER STORY 04 The University of Hong Kong Bulletin | May 2022 05

About a decade ago, Dr Tom McDonald of the Department of Sociology was studying media use in rural China. But the deeper he got into his topic, the more he realised something bigger was afoot. Money exchanges on different kinds of social media were aligning with different kinds of social relations –WeChat for close friends and family, QQ for gaming and distant acquaintances, and Alipay for third parties and businesses. Workers were spending large amounts of their free time on social media to collect virtual money convertible to tiny amounts of real-world money. “It became obvious that money in China was becoming social media and that you couldn’t study the media in China anymore without having an awareness of what money was and how media itself was increasingly becoming transactional,”he said. So he set out to learn more about money from an anthropological perspective, a journey that led him to develop a Common Core course on the topic and research further into the role of money in society. “Many economists believe that human beings are rational economic actors, that our use of money is primarily as a medium of exchange and that we act in self-interested ways. However, anthropologists look at the way people really use money out in society and it’s quite obvious that a lot of our monetary practices are deeply irrational,”he said. Emotional need Things like gambling and shopping sprees can be motivated by emotional need, social signalling or even just a feeling of satisfaction from the act of spending money. Stock market bubbles are also led by emotion. “When money seems to have this capacity to generate more money, people fear they are missing out and they pile into the stock market, further increasing the value. But when confidence changes, they want to turn their capital into cold hard cash. Suddenly, you get a crash,”he said. Contemporary understanding of money, debt and value is also changeable, he said. For example, the modern idea of debt allows creditors to earn money by charging interest, while in the past debt was seen as a straightforward exchange of favours between people. Physical money has changeable forms, from the kula shells still used for exchange in parts of Papua New Guinea to the SMS money transfers that proliferate in Haiti, where most people do not have bank accounts or identity documents. The monetary value attached to objects is also not fixed, as seen most explicitly in art auctions where auctioneers use various techniques to push the price of artworks to their highest possible value. All these issues are explored on the course with the aim of getting students to reflect on the role of money in their lives and in society, he said. Their output has included taking photos or videos that document the use of money in their communities, such as the monetary debt implied in filial obligations and the Apart from the Common Core course, Dr McDonald also recently completed a research project that highlights the human relations that remain pivotal to money exchange. Looking at cross-boundary transactions among people who travel regularly in the Greater Bay Area, he found they often rely on friends and family for crossboundary money exchange, for example, by transferring Hong Kong dollars to a friend through one account and being repaid by the friend in RMB through a different account. social signalling behind the city’s obsession with luxury watches (the results are at Students also compose essays in the form of letters outlining problems with money and future scenarios, such as writing to the World Bank about wiping out national debts and setting out the arguments on why children should receive pocket money. Crypto questions Dr McDonald said the topic was timely for students, not only because they will soon be making decisions about careers to pursue and how to spend their earnings, but because new forms of money are taking hold. “Students are fascinated by cryptocurrencies and NFTs [non-fungible tokens],”he said. “In the end, it’s important that they realise money is created by human beings and that it has not always been the way it is now. All these new technologies are re-drawing the possibilities of money and the relationships involved in money. For example, many cryptocurrencies cut out the traditional banking system and often the state. Is this desirable? Is this what we want?” This is cheaper and avoids the bureaucracy of regular banking. “Despite the promise of things like digital wallets and new virtual banks in Hong Kong, people often still fall back upon informal transactions,”he said. Visit the Hong Kong Money Museum SOCIAL RELATIONS AND MONEY Money is a form of exchange between humans. As such, it is used in ways that can be irrational, emotional and changeable. Dr Tom McDonald has been shining an anthropological lens on the nuances of our relationship to money. DR TOM MCDONALD In the end, it’s important that they realise money is created by human beings and that it has not always been the way it is now. COVER STORY 06 The University of Hong Kong Bulletin | May 2022 07

Money is different things to different people, none more so than economists and anthropologists. Economists often see money as an instrument that makes bartering in the market run smoother – it’s easier to trade dollars than lug around actual cows and bags of rice for exchange. But anthropologists and other social scientists increasingly argue that money precedes markets and in fact is created by states to create legitimacy and support their work. Dr Oscar Sanchez-Sibony came across these arguments as he was delving into the economic history of the Soviet Union. He wanted to understand why, after taking power in 1917, the Bolsheviks signed their country up to the gold standard, to which major capitalist economies of the day had pegged their currencies to make them more interchangeable. “The gold standard underpinned capitalism in the pre-WorldWar One era and was an institution designed to protect financial interests and capital, so it seemed very surprising that anti-capitalist revolutionaries would join the gold standard. This was why I started to look into theories of money and how it works and gets created,”he said. The theory that best fits the Soviet Union is that money is an instrument of the state to create social obligations that can be paid back in taxes. Money makes tax collection easier by obviating the need go to farms and take a share of produce to support state functions. Rebuilding bonds The Soviet Union was enlightening on this point because it did not have a stable currency until 1923 when they issued their own goldbacked rouble (chervonets) which, even then, did not take hold right away. For the first few years after 1917, the main forms of exchange were old imperial roubles and sacks of wheat – rather than moving actual sacks around, people recorded debts and payments in wheatsack terms. Acceptance of the Soviet rouble became important not only for practical reasons, but also because it meant the Soviet government could collect resources from people through taxes to rebuild the state and establish social cohesion. “The Bolsheviks were unpopular, especially in the countryside, and they were trying to create a new state after one of the most destructive civil wars ever, which was followed by famine. They were trying to rebuild bonds back up within society. Money is such a great instrument for doing that, among other things, because it creates markets,”he said. The adoption of the gold standard also had a political aim of showing bankers, investors, and ‘capital’ in general that the Bolsheviks were good financial stewards whose money would not suddenly devalue. This was necessary because all countries were trying to increase exports. “The Bolsheviks did that more than anybody by continuing to lower prices even at great pain to citizens.” The Soviet Union was also one of the few countries to pay off all its debts during the Great Depression and never declare bankruptcy (though it had defaulted on the Tsar’s debts in 1918), which Dr Sanchez-Sibony said was because the Bolsheviks still wanted international capital. “If you take the view that money is just an instrumental thing with no meaning, then you miss understanding why they paid off their debts at such a huge cost.” because the Soviets wanted to continue to export wheat and other commodities – collected from citizens even at gunpoint – to trade for industrial equipment and products. But that aim hit a bumpy road when the gold standard started crumbling in the late 1920s. Countries were forced to devalue their currencies and they began to undercut each other, leading to disruptions to trade and ultimately, the Great Depression. A small return The Soviets responded by collectivising farming to increase their acquisition of grain, a problem all governments faced at that time. Initially, 15 per cent of farms were targeted, but farmers were reluctant to sell to the state at low prices. When Joseph Stalin consolidated his leadership in the late 1920s, he ramped things up violently to the extent that the entire countryside was collectivised and famine and death ensued. It was a high price to pay for a small return. “It turned out that even as they seized this grain, they still weren’t able to export it for industrial inputs,”Dr Sanchez-Sibony said, Dr Sanchez-Sibony noted that the state-linked view of money continues to have relevance today because money continues to serve the state. For instance, after the 2008 financial crisis, US policy was to print money and save banks and the banks of its allies. Earlier, after the 1997 Asian financial crisis, many governments built up large reserves of US dollars to protect against future economic collapse. “Vladimir Putin learned the lesson well. To a large extent, he has been able to withstand a lot of pressure from the US precisely because of the large reserves Russia built after 1998 on the back of oil and gas,”he said. The chervonets was the gold-linked paper money the Bolsheviks produced in order to build credibility with their citizens and foreign investors. The name denotes a certain conservatism, recalling the 15th- century Russian name for the Dutch ducat, which in time came to refer to different foreign gold currencies. Red Globalization: The Political Economy of the Soviet Cold War from Stalin to Khrushchev (left) written by Dr Oscar Sanchez-Sibony and its recently translated Russian version (right). MONEY AND THE STATE What comes first, money or markets? Historian Dr Oscar Sanchez-Sibony’s investigation of the Soviet Union’s early years provides strong evidence that money comes first and that it is a creation of the state. DR OSCAR SANCHEZ-SIBONY If you take the view that money is just an instrumental thing with no meaning, then you miss understanding why they paid off their debts at such a huge cost. COVER STORY 08 The University of Hong Kong Bulletin | May 2022 09

Many factors lay behind China’s slowness to industrialise and gain control of its economy in the 19th and 20th centuries. But a key one was money: there was no unified currency and no capital markets in the country through which the government could raise money. Dr Ghassan Moazzin has been studying the situation, whose consequences reverberate today. In the 18th century, the Qing dynasty was at its height: China was a global superpower and its coffers were full. By the end of the next century, all that had changed. While other major regions, in particular Europe and North America, were industrialising, China lagged well behind. While there were many reasons for China’s weakness, recent research suggests that the lack of a unified currency and capital markets made it difficult for the country to emerge from the quagmire, according to economic historian Dr Ghassan Moazzin of the Hong Kong Institute for the Humanities and Social Sciences and the Department of History, who has written a book on foreign banking and international finance in China from 1870 to 1919 that is about to be published this summer. “The Chinese government before the 19th century did not really get involved in the Chinese economy all that much. Then they realised that the country had fallen behind and they needed to come in and help the economy somehow,”he said. “If you want to do that, you want to have control of the currency. You also want to have your own capital markets at home where you can borrow money.”China had neither of these things. On money, two kinds of currency circulated in the 19th century – copper coins issued by the government and used for everyday transactions, and silver, which was used for expensive purchases and, importantly, to pay taxes. The silver currency was imported mostly from Spanish America and each region within China had its own system of measuring and calculating the value of silver. “The government did not really have any control over the supply and circulation of silver in the economy and this led to important problems,”Dr Moazzin said. Affecting state development In the early 19th century, different factors led to the appreciation of silver, which in turn had a negative impact on the economy. The government made various attempts to deal with the problem, but it did not succeed until after 1927 when the Nationalists gained control. “They managed to do a quite successful currency reform in 1935 but then the SinoJapanese War came. It was only after 1949 that the Chinese government managed to properly reform the currency,”he said. “When we think about how different generations of Chinese political leaders and Foreign Banks and Global Finance in Modern China: Banking on the Chinese Frontier, 1870–1919 is forthcoming from Cambridge University Press. Bond for a Chinese government loan, 1898. (Image courtesy of Deutsche Bank AG, Historical Institute) reformers tried to build a Chinese nation, the monetary question and how to develop a unified Chinese currency system that the state has control over is not something that comes up much. But recent research by financial historians indicates that there is a thread that you can draw from the mid-19th century all the way to the mid-20th century.” The lack of capital markets also affected state development. Unlike Western powers, China could not turn to markets at the outset of its industrial revolution to help fund railways, trading companies, large factories and other major ventures. “For the Chinese state, it was just unthinkable that you would borrow money from your citizenry. If you had to do so, if your treasury was basically empty, it meant things were not going well,”Dr Moazzin said. Cautious about foreign banks To get funds for industrialisation projects, the government had to look abroad. Foreigners were happy to finance Chinese bonds because the return was better than many European government bonds. Other developing countries experienced the same phenomenon. “China could quite easily borrow money abroad, maybe a bit too easily, and later defaulted on a lot of that money,”he said. Foreign banks, such as the Hong Kong and Shanghai Banking Corporation, helped connect the country to foreign markets and played an important role in the Chinese economy. They also issued their own banknotes, which further complicated the currency problem (in Hong Kong, some of these banks still issue currency). While the government made some attempts to establish homegrown capital markets to borrow from Chinese investors, these did not really work until the 1920s – at which time it became more difficult to borrow from abroad. Since 1949, China has again gradually developed its own capital markets, but has at times also raised capital abroad. A possible legacy of all this is that China remains cautious about foreign banks and has restricted their activities in the country. “We can connect this to the experience of foreign banks being so powerful in the late 19th and early 20th centuries in China. After the 1980s, the government was quite cautious to make sure that doesn’t happen again.” DR GHASSAN MOAZZIN Postcard showing the Shanghai Bund, early 20th century. (Image courtesy of Ghassan Moazzin, private collection) MONEY, MARKETS AND THE RISE OF MODERN CHINA The government did not really have any control over the supply and circulation of silver in the economy and this led to important problems. COVER STORY 10 The University of Hong Kong Bulletin | May 2022 11

The best things in life are free But you can give them to the birds and bees I need money (That's what I want) These lyrics come from an old American pop tune that has been covered by the Beatles and many other popular bands. But that fondness for material over emotional desires also fascinates psychologists, including Professor Chen Zhansheng, who has been studying the way money shapes how we think, feel and behave, as well as exploring cross-cultural differences. “There is a long literature on materialism, which basically studies people’s values and how they think about money. Do you think money is the most important thing in life? How do you place money versus other things, for example your relationships and maybe your contributions to society?” he said. Common sense might suggest that ranking money, or materialism, highly will negatively influence how one relates to others. Professor Chen’s research has been providing the hard evidence of causal effects, ruling out other factors, and trying to explain why this might be. For instance, he has found that those high in materialism, as measured in questionnaires and experiments, tend to treat other people as instruments to facilitate goal achievement, such as networking for business connections. This makes them less able to empathise with others and follows on from other research that has found highly materialistic people can be more hostile and aggressive in the face of conflict. Public health concern Furthermore, people high in materialism also tend to unconsciously objectify themselves. “Such people are more likely to be very goal-oriented and spend a lot of effort and attention to sharpening their skills, staying motivated, and trying to create more wealth and gain more fame. In the meantime, they may lose touch or neglect qualities related to caring and compassion,” he said. “It may be that this will be problematic for public health. This is an area I want to pursue in future.” He has already done related research showing the COVID-19 pandemic may be harder on highly materialistic people. The study, done in early 2020, was motivated by the fact people had to stay home and their chances to make money were diminished. “At that stage, people with higher materialism tended to experience a high level of stress and anxiety,” he said. Another finding is that people with high materialism can also experience a small but significant effect on their expression of emotions. In one experiment, he had people read an article about the pros or cons of a money mindset. Those reading about the pros were subsequently more reserved about expressing emotions. “This is an implicit process and they are probably not aware of it – they may still internally feel these emotions, but they don’t want to show their emotions to minimise any potential impact on goal attainment.” Professor Chen noted high materialism is not always bad as it can make people more efficient at work and enable them to gain more financially. It also does not strongly correlate to generosity or helpful behaviours as people may donate or volunteer for reasons unrelated to materialism, such as tax write-offs or to gain a favourable opinion from others. a person lives. Professor Chen has ongoing studies on cross-cultural differences that show residents of urban financial centres like Hong Kong or economic powerhouses like the US and China tend to be more materialistic than residents in quiet rural areas, such as a village in Thailand. But comparisons of the US and China show they are more alike than different. “In terms of empathy and pro-social behaviours, we have found that the patterns are similar. There are bigger differences within a country or culture than between them,” he said. “The relationship between materialism and helping behaviour is complicated, but the relationship with empathy is quite clear,” he said. “It shapes how you interact with others and also how you process information and treat yourself. It is not such a good thing to have this high materialistic value, especially for personal well-being.” Cross-cultural comparisons While materialism could be considered a personality trait, it can fluctuate or intensify depending on factors such as age and where He points to the example of China, where people have been found in surveys to be among the most materialistic on Earth yet are strongly willing to support those closest to them without recompense. “People are very generous to their close kin – their kids, their parents and close relatives. It seems like they create a protective nutshell around them that is not so influenced by materialism. But when dealing with others outside these close bonds, then they become very materialistic,” he said. Our attitudes to money can influence our behaviour towards others and even impact our mental health, finds Professor Chen Zhansheng of the Department of Psychology. PROFESSOR CHEN ZHANSHENG It shapes how you interact with others and also how you process information and treat yourself. It is not such a good thing to have this high materialistic value, especially for personal well-being. MATERIAL VALUES COVER STORY 12 The University of Hong Kong Bulletin | May 2022 13

Current vaccines for SARS-CoV-2 have done well protecting people from severe illness and death, but some studies have shown that even vaccinated people may continue to carry quite high levels of the virus in their nose, a situation that may underlie asymptomatic transmission and re-infection. In response, HKU researchers have developed new vaccines that can address that problem and are both cheap and easy to manufacture. Professor Chen Honglin has drawn on his earlier work on a vaccine for influenza and coronaviruses to develop a nasal vaccine for COVID-19, while Professor Chen Zhiwei has adapted an HIV-AIDS vaccine he has been working on into an injectable COVID-19 vaccine. While work on their earlier vaccines is still going through the years-long process of pre-clinical and clinical trials, the urgency of COVID-19 has helped speed things up for the new vaccines and encouraged them to look at the effectiveness of combining the two. After multiple tests, they found that the injectable vaccine followed by a booster from the nasal vaccine could offer protection against the virus and reduce the viral load in the nose in animal trials. The findings were published late last year in The Lancet’s online journal EBioMedicine. “So far, this is the only vaccine combination able to block nasal infection and provide effective protection in both the upper and lower respiratory systems,” Professor Chen Honglin said. The nasal vaccine also has potential as a booster for people who have received Pfizer-BioNTech or other mRNA-based vaccines. Building expertise The origins of these vaccines date back two decades ago when, following the SARS outbreak in 2003, HKU began to build up expertise in infectious diseases. It is now a world leader in the field, hosting Post in April this year headlined, “The next leap in coronavirus vaccine development could be a nasal spray”. Professor Chen Zhiwei’s new vaccine is built on the model he developed for an HIV-AIDS vaccine. This DNA-based vaccine has been going through the conventional vaccine testing and approval process since 2013 and has a special way of delivering the antigen to antigenpresenting cells that induces potent antiviral immunity. For SARS-CoV-2, he swapped the HIV gene for the COVID-19 virus and has found that on its own, this vaccine can provide protection similar to that of mRNA vaccines while being cheaper and easier to manufacture. It can also be easily adapted to new variants. Hurdles to development The Lancet study reported on a variety of combinations using the two vaccines in animal models, with the best version being an injection among other things the State Key Laboratory of Emerging Infectious Diseases, which is led by Professor Chen Honglin and includes team member Professor Chen Zhiwei, who also is Director of the AIDS Institute at HKU. Before 2020, Professor Chen Honglin had been working on a vaccine candidate that showed potential for protection against both influenza and coronaviruses, by knocking out the NS1 gene from the NS segment in an influenza virus and inserting a receptor-binding-domain of the MERS (Middle East Respiratory Syndrome) coronavirus in its place. He quickly managed to replicate and insert SARS-CoV-2, which is also a coronavirus, and showed that it offered good protection against the virus. He also decided to focus on developing his findings into a nasal vaccine that provides ‘frontline’ protection where the virus can enter the body. Although a nasal form takes longer to develop than other vaccines, it is cheap and easy to deploy and has the potential to be a second-wave vaccine to boost immunity. There is also growing interest in this form of vaccine, as exemplified in an article in The Washington Researchers at HKU have been finding new ways to contain the COVID-19 virus and protect people from infection. Professor Chen Honglin and Professor Chen Zhiwei in the Medical Faculty have developed a novel vaccine strategy using an injection and nasal spray that may offer better protection and prevention against asymptomatic transmission of the virus. And engineers led by Professor Mingxin Huang have developed a new stainless steel that is COVID-resistant and effectively kills the virus. FIGHTING BACK AGAINST Professor Chen Honglin (left) has drawn on his earlier work on a vaccine for influenza and coronaviruses to develop a nasal vaccine for COVID-19. The nasal spray vaccine manufactured by Wantai BioPharm is currently in the third phase of trials in the Philippines, South Africa, Columbia and Vietnam. PROFESSOR CHEN HONGLIN So far, this is the only vaccine combination able to block nasal infection and provide effective protection in both the upper and lower respiratory systems. VACCINE BREAKTHROUGHS C VID-19 14 RESEARCH The University of Hong Kong Bulletin | May 2022 15

followed later by the nasal vaccine. However, they still must complete safety tests individually before they can be tested together in humans. The nasal vaccine is being developed with Wantai BioPharm, a Chinese pharmaceutical company, and is currently undergoing phase two and three clinical trials in the Philippines, South Africa, Columbia and Vietnam. The DNA-based vaccine has just finished a phase one trial that confirmed it is safe in humans. It is being developed in partnership with Immuno Cure Biotech Ltd in Hong Kong, which has worked with companies in the Mainland that have GMP [Good Manufacturing Practice] facilities for pre-clinical and clinical testing. Both professors said the lack of GMP manufacturing in Hong Kong had slowed down their vaccines’ development because they had to look elsewhere for partners and testing facilities. Professor Chen Zhiwei hopes the government will reconsider its investment in this area, especially as other viruses are likely to threaten in future. When the first COVID-19 vaccines appeared, the government had to turn to sources outside the city in competition with other governments. “We have the talent and expertise here with the State Key Laboratory and many scientists working on all kinds of viral diseases. Even when we can design a vaccine, the wait time from bench to human trial has been very long because of the disconnection in the middle and the lack of manufacturing capacity. I hope this situation can be changed so we can be prepared for future pandemics,” he said. Tuning stainless steel The team achieved inactivation of pathogen microbes (especially the SARS-CoV-2) on the stainless steel surface by tuning the chemical composition and microstructure of regular stainless steel. The research also found interesting points about Ag and Cu as the alloying elements to prepare anti-pathogen stainless steel, namely that stainless steel containing Ag is good at killing bacteria, but cannot inactivate the virus, while stainless steel with a high Cu content (10 per cent or above) can effectively kill bacteria and virus. Ordinary stainless steel has no inherent antimicrobial properties and studies have shown that the SARS-CoV-2 can remain stable and viable for as many as three days. Since crucial public areas such as hospitals and kitchens have myriad stainless steel surfaces, they also have a high possibility for virus transmission among people. Said Professor Poon: “Recent data suggests that Omicron is more stable than the original SARS-CoV-2 on different environmental surfaces. This suggests that Omicron has an increased likelihood to be transmitted by fomite (i.e. objects or materials likely to carry infection, such as clothes, surfaces, utensils and furniture). The stainless steel developed by us can reduce such risk.” Existing surfaces cannot be adapted to the new technology and would need to be replaced with the tuned stainless steel. Already there has been a lot of interest from the industry. “Many local Hong Kong, Mainland, international companies have contacted HKU for potential use of our anti-COVID-19 steel,” said Professor Huang. “HKU Technology Transfer Office is talking to several companies regarding potential licensing and costs. If the negotiations go well, we may be able to see real products in the near future. “The team has produced prototypes, including lift buttons made from the anti-COVID-19 stainless steel using mature powder metallurgy technologies. Its successful fabrication indicates a promising prospect for the production of future anti-COVID-19 stainless steel products.” As COVID-19 continues to maintain its hold on Hong Kong, the development of a virus resistant stainless steel whose surface kills SARS-CoV-2 has big implications for use on frequently-touched areas such as lift buttons, door handles and handrails. E. coli and the H1N1 virus can also be inactivated on the surface of this special stainless steel. The research, which was published in Chemical Engineering Journal, is a cross-disciplinary project led by Professor Mingxin Huang in the Faculty of Engineering’s Department of Mechanical Engineering, in collaboration with Professor Leo Lit Man Poon’s research team at the School of Public Health, HKUMed. Their work in this area began four years ago, before COVID had emerged. “We started studying antibacterial and anti-H1N1 stainless steel and successfully invented antibacterial stainless steel containing silver (Ag) in 2019,” said Professor Huang. “When the COVID-19 pandemic began in early 2020, we changed our focus to anti-COVID-19 stainless steel. At the beginning, we thought we would be able to use our antibacterial steel for anti-COVID-19 purposes. But it failed, so then we invented our new anti-COVID-19 stainless steel that contains 20 per cent copper (Cu). The virus is killed by the Cu ions released from the steel surface.” Existing technology It is also viable in terms of production technology. “The stainless steel can be tuned using existing powder metallurgy technology, so it is quite ready for mass production,” Professor Huang continued. Said Mr Litao Liu, the first author of the journal article and a PhD student supervised by Professor Huang: “Massive Cu-rich precipitates are permanently present in the stainless steel matrix. Thus, this antiCOVID-19 stainless steel can chronically inactivate pathogen microbes even though its surface is continuously damaged, meaning that even if the surface is scratched or dented, the inactivation of the virus microbes will continue.” Summing up, Professor Huang said: “This anti-COVID-19 stainless steel can replace some of the frequently-touched stainless steel products in public areas to reduce the risk of accidental infection and help fight the COVID-19 pandemic. In addition, the findings on Ag and Cu as the allying elements to obtain antiviral and antibacterial properties have provided useful information for the future development of other forms of anti-pathogen stainless steel.” Sample of the anti-COVID-19 stainless steel that can kill the severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2) on its surface. Professor Chen Zhiwei’s new injectable COVID-19 vaccine is built on the model he developed for an HIV-AIDS vaccine. The team has produced prototypes, including lift buttons made from the anti-COVID-19 stainless steel using mature powder metallurgy technologies. Its successful fabrication indicates a promising prospect for the production of future anti-COVID-19 stainless steel products. PROFESSOR MINGXIN HUANG PROFESSOR CHEN ZHIWEI The wait time from bench to human trial has been very long because of the disconnection in the middle and the lack of manufacturing capacity. I hope this situation can be changed. Developed in partnership with Immuno Cure Biotech Ltd in Hong Kong, the DNA-based vaccine has just finished a phase one trial that confirmed it is safe in humans. STEELING A MARCH 16 RESEARCH The University of Hong Kong Bulletin | May 2022 17

Increased ocean acidification (OA) in recent decades means that pH levels in the global oceans are predicted to decline to levels which may affect some marine fish. Knowing how it will affect growth, behaviour and even survival of various types of fish is essential to working out how to optimise their conservation and management. Dr Celia Schunter at HKU’s School of Biological Sciences and the Swire Institute of Marine Science, led the study, working with teams of researchers from Japan, Australia and New Caledonia in the natural laboratories of Papua New Guinea. “The most important discovery we made,” said Dr Schunter, “is that the difference in evolutionary rate (over millions of years) provides the fish which evolved more rapidly with the flexibility to acclimatise. They can rapidly adjust the expression in a larger number of genes, which provides certain species with an ability to respond to the environmental changes such as elevated pCO2 [partial pressure of carbon dioxide].” The team carried out their research in Papua New Guinea’s UpaUpasina seep. “Volcanic CO2 seeps in Papua New Guinea can be used as natural laboratories, where CO2 rises from the substratum and acidifies the surrounding seawater to levels similar to, or sometimes beyond, the projections for OA by the end of this century,” said Dr Schunter. “Despite these ‘future’ conditions, many species still live in these seeps and studying them can allow us a peek into future ecosystems. “While previous studies investigated the molecular response to elevated pCO2 in different species, these investigations were performed in controlled aquarium systems. This study is the first of its kind to compare across species in a natural setting.” Storm sparks discovery Nature also provided their work with another boost when a heavy storm rapidly changed the pH levels in the seep. “The storm brought many difficulties for sampling and complicated the field work,” said Dr Schunter. “But, at the same time, it also provided us with key evidence of the flexibility of the spiny damselfish species A. polyacanthus to adjust to pH changes.” In particular, A. polyacanthus lacks a larval dispersal phase, which leaves this species with a more pressing need to adapt to local conditions than species with a dispersive larval phase. “We see this as the species has many positively selected genes across its genome, which means that selective processes are at play to adjust its genome to better live in local environmental conditions,” said Dr Schunter. “Maintaining pH and ion transport homeostasis are key challenges for fishes when coping with elevated pCO2. This fish can adjust the expression of core circadian rhythm genes, which regulate the expression of the downstream gene related to intracellular pH regulation and ion transport.” Circadian rhythms are near-24-hour oscillations found in nearly all aspects of physiological processes in the vertebrate brain and body. The circadian clock also runs our daily lives and adjusts our metabolism to the time. Dr Schunter explained that you know the circadian rhythm is at play when you get tired in the evening or get hungry around the same time each day. In short, she said, A. polyacanthus has developed a molecular toolkit, which will enable it to cope better with pH variations. “Previously we didn’t understand why some species struggle with OA more than others. This time we saw that A. polyacanthus can regulate the pH levels within its cells through the gene expression changes in response to the environmental elevated pCO2 at the CO2 seep. We originally thought that an elevation in the pCO2 to end-of-century predictions would not be a large impact to fishes, as they know how to regulate the pH, however we see that these coral fish species induced significant expression changes in many genes. This underlines the need to regulate the cells in the brain in response to the CO2 levels in the ocean waters. Reversible changes The arrival of the storm, which lasted 24 hours at the remote reef, moved a lot of water of the CO2 seep site and increased the pH temporarily. “We were able to collect some spiny damselfish during this time and now see that all the cellular changes are reversible as they changed quickly back to the levels of what we see at the control reef with current-day CO2 levels.” However, although this particular species has coping mechanisms there is still cause for alarm at the pace of OA. Rapid environmental changes – caused by humans – are a threat for fishes, especially for slowly evolving fish species, said Dr Schunter. “Even for A. polyacanthus, it can be a problem if the environment changes faster than its ability to regulate the cellular activities. As such, it’s important for us humans to slow down the activities which accelerate the environmental changes.” The research continues with further studies underway. “These include other fish species from different ecosystems (but also from CO2 seeps) to understand the general applicability of our findings across all marine ecosystems (not just coral reefs),” she said. “Furthermore, as the circadian rhythm clearly plays an important role in the adjustment to changes in pH in fishes, we will investigate further the mechanisms and adaptive potential underlying this.” Rapid Response A study has shown that fish species which have evolved more rapidly in the past are equipped with better means to cope with increased ocean acidification across the globe. A. polyacanthus may possess evolved molecular toolkits to cope with future ocean acidification. DR CELIA SCHUNTER The storm brought many difficulties for sampling and complicated the field work. But, at the same time, it also provided us with key evidence of the flexibility of the spiny damselfish species A. polyacanthus to adjust to pH changes. 18 RESEARCH The University of Hong Kong Bulletin | May 2022 19

Many carnivorous animals do not have the ability to taste sweetness, and it was previously unclear if birds – which are descendants of meat-eating dinosaurs – could or not,” said Dr Simon Sin Yung-wa, Assistant Professor in the School of Biological Sciences and a member of the international team that did the research. Cues for survival It was important to find out because sensory systems evolve and adapt to allow animals to perceive cues important for survival. “The evolution of sensory receptors can affect the behaviours of a species and have profound ecological consequences,” said Dr Sin. “This may ultimately lead to speciation and adaptation radiation.” We are all familiar with the ubiquitous image of a hummingbird hovering in front of a flower as it drinks the nectar but scientists only proved they could in fact taste sweet in 2014. Now a new study has shown that songbirds are also able to distinguish sweet tastes but they evolved this ability in different ways to the hummingbird. “Birds are the most diversified terrestrial vertebrates, widely distributed on this planet and occupying different ecological niches,” he said. “The common ancestor of all birds, carnivorous dinosaurs, lost a subunit of the sweet taste receptor and hence the ability to taste sugar. However, we observed that many birds do eat sweet foods like nectar.” They did know that some songbirds, like the sunbirds, consume a lot of nectar, but wanted to find out if all of them could taste sugar, and if so when this ability evolved. “The evolution of a new taste sense could have a big implication in the evolution and radiation in this group of birds, which includes almost half of the extant bird species,” said Dr Sin. Twelve species of songbird were tested, including the warbling white-eye (Zosterops japonicus) which is a resident in Hong Kong and the carrion crow (Corvus corone) which, according to Dr Sin “was seen in Hong Kong but it’s only a vagrant”. The leader of the research team, evolutionary biologist Dr Maude Baldwin from the Max Planck Institute for Ornithology, was the researcher who elucidated the evolution and mechanism of sweet perception in hummingbirds. Dr Sin was in the same laboratory as Dr Baldwin while they were at Harvard and he joined her in studying the evolution of taste perception in the songbirds. “In hummingbirds, the umami receptor, which detects amino acids and is responsible for the savoury taste, evolved to become a sugar receptor,” said Dr Sin. “We found that songbirds are also able to taste sugar but we didn’t know how they are able to do that. Did their umami receptor also transform into a sweet receptor? If so, were the same or different mutations involved? Therefore, in this study we investigated the genetic basis and mechanism of sweet perception in the songbird to understand how different lineages of birds convergently evolved the same sensory ability.” Generating chimera Their methodology for identifying modifications to the umami taste receptor involved “a lot of experiments to generate chimera (for example between ancestral and current umami receptors) or introduce mutations to the receptors, and then test whether those receptors could be activated by sugar,” he explained. “By changing the composition of the umami receptors in this way we were able to identify the positions that are crucial for the transformation of the umami receptor to a sweet receptor.” They found that although both hummingbirds and songbirds re-gained their sweet perception through mutations in the umami receptor, the changes in songbirds and hummingbirds coincide only slightly, even though similar areas of the receptor were modified. “These distant bird groups converged on the same solution of re-purposing their umami taste receptors to sense sugar over evolutionary time,” said Dr Sin. “However, each group modified the receptors in distinct ways to achieve the same outcome.” The team was able to discover when this ability evolved by reconstructing the ancestral umami receptors at different locations on the songbird family tree, using the information of the umami receptors in extant species to test the receptor activity towards sugar. “It turns out that the early ancestors of songbirds evolved the ability to taste sugar, even before they radiated out of Australia [where most songbirds originated] and spread across the planet,” said Dr Sin. “We were very surprised by this result. While, in Australia, many different sugar sources are common, including insect secretions and tree sap, sugary food sources may have also helped songbirds spread to other continents and successfully occupy a variety of ecological niches.” Sweet deal for songbirds Scientists have discovered that songbirds evolved the ability to taste sweetness and believe that this has far-reaching implications for their subsequent evolution and radiation. A New Holland honeyeater (Phylidonyris novaehollandiae) feeding on Wilson’s grevillea (Grevillea wilsonii), a favourite honeyeater food endemic to Western Australia. (Image courtesy of Gerald Allen, Macaulay Library) A New Holland honeyeater (Phylidonyris novaehollandiae) perched on a banksia in Western Australia. (Image courtesy of Gerald Allen, Macaulay Library) DR SIMON SIN YUNG-WA Distant bird groups converged on the same solution of re-purposing their umami taste receptors to sense sugar over evolutionary time. However, each group modified the receptors in distinct ways to achieve the same outcome. 20 RESEARCH The University of Hong Kong Bulletin | May 2022 21