The Review 2008

28 29 patterns. They focused specifically on a proper ty in bacteria thatmakes it constantly tumble.Theyprogrammed whenthe bacteriamoved in relation toother cells,and in what direction. Initially they made the bacteria form a single blue ring then they quickly moved on to multiple rings and even hexagons as seen on a football. A control dish of bacteria that was not programmed spread out into a grey blob.The results were repeatable and videotaped to record the pattern formation. Dr Huang Jiandong of Biochemistry, one of the scholars overseeing the project together with Professor Chen Guanhua of Chemistry, Chair Professor Zhang Fuchun of Physics and Distinguished Visiting Professor Terry Hwa from the University of California, San Diego, said the results helped to fuel interest among students at a time when the University is trying to build up research exper tise in synthetic biology. “We’re trying to use this project as an educational tool.We ultimately want to conver t sunlight into energy and for that you need good scientists who understand the biology and the physics. This is as much about the project as it is training up the right people,” he said. The students are studying physics, chemistry,biology and biochemistry.The results of their project are likely to be published, but the work has already earned them a Bronze Medal in the International Genetically Engineered Machine (IGEM) competition at the Massachusetts Institute of Technology. 2008 was the first year HKU had entered the annual event and the students were up against 84 international teams. “This is now not only a project for a competition but a scientific project,” biochemistry PhD student Liu Chenli said. “It’s the first repor t in the world of making bacteria move into cer tain patterns, and we have discovered the mechanism underlying it.” Language and Perception Does language influence our perception of the world, or is it the other way around? That question is no longer solely the domain of philosophers. Science has stepped in, and research at HKU has recently provided insight on how language and perception interact. Scholars here focused on the perception of colours in the brain in relation to language processing. Evidence from elsewhere had suggested language might have an influence. For example, English speakers judge colours straddling the boundary between blue and green as less similar than speakers of Tarahumara, a Mexican language that uses a single word for these colours. But until now there has been little evidence to measure these differ- ences in the brain. In exper iments carr ied out in our State Key Laborator y of Brain and Cognitive Science, HKU researcher s hooked subjects up to neuro-imaging technology to monitor brain activity as they performed an activity on language and colour. The subjects were asked to decide whether two squares were of the same colour. Some of the squares were filled with easy to name colours, such as red and blue, and others with harder to name ones. Significantly, no actual use of colour language was required. Both kinds of colours engaged the same cor tical regions associated with colour vision. But when it came to easy-to-name colours, there was also strong activity in two other areas of the brain responsible for word searching. This suggested a close link between language processing and colour perception. “These findings represent a major breakthrough on this research topic by providing neuro-physiological evidence in suppor t of the hypothesis that language may affect thought and perception,” Professor Tan Li-Hai of the Depar tment of Linguistics said. The findings, which also involved input from colleagues at the University of California, Berkeley and were published in March 2008 in the Proceedings of the National Academy of Sciences , open up new oppor tunities for studying the human mind. Fur ther research could also shine a light on how to enhance the effectiveness of foreign language learning. The project was funded by HKU, China’s National Strategic Basic Research Programme and the US National Institutes of Health. A World First for Student Researchers A team of students at HKU has made a new discovery in the emerging field of synthetic biology, for the first time programming bacteria to form regular patterns by controlling their movement. Synthetic biology involves applying physics, chemistry, engineering, maths and other disciplines to biology to control the patterns and behaviour of cells. The hope is that this can eventually be used to devise bacteria to treat cancer and conver t solar energy into biofuels. A team of undergraduates, working with a postgraduate student, have been able to control communication between cells to make them form The Review 2008 • Research Students programmed bacteria to produce patterns in Petrie dishes.