World update

At a recent conference held on the evolution of infectious diseases, pathologist Nissi Varki, University of California, San Diego ( UCSD), observed that humans suffer from a long list of fatal diseases — including typhoid fever, cholera, mumps, whooping cough, measles, smallpox, polio, and gonorrhea — that don't bother chimpanzees and most other mammals. Both these bacteria follow the same mechanism to get into our cells: they target sugar molecules called sialic acids. Hundreds of millions of these sugars study the outer surface of any cell in the human body — and human sialic acids differ from apes. Varki and an international research team have now studied how nature could have struggled to develop new defenses after molecular instability appeared in our distant ancestors. Through studying current human genomes and ancient DNA from our extinct ancestors, Neanderthals and Denisovans, the researchers found an evolutionary explosion of our immune cells that happened at least

China named a hard-line figure to lead Hong Kong 's newsecurity agency. Zheng Yanxiong is best known for his role in dealing with a land dispute protest in Wukan, southern China. The new organization, responding directly to Beijing, is set up in Hong Kong this week to implement a draconian security law. Regulation critics claim it erodes territorial freedoms. With up to life in prison, the law opposes secession, subversion and terrorism. Many leading pro-democracy activists have abandoned their positions and one of them, once student leader and local legislator Nathan Law, has fled the region. Separately, one of ten people arrested during demonstrations on Wednesday has been the first to be convicted under the new legislation. Hundreds were arrested in clashes. The motorcyclist was charged with promoting secession and extremism, accused of riding into a group of police while holding a banner calling for Hong Kong 's independence. Beijing has rejected critici