By tinkering with yeast and sea slugs, scientists have found a surprising possible explanation for the way the human brain stores long-term memories. \nThese lowly creatures possess an unusual protein that exists in two shapes. In one shape, the protein is sluggish or inactive. In its second shape, the protein perpetuates itself indefinitely but can also harmlessly switch back to the inactive form. \nResearchers believe that in higher organisms the same protein may exploit this second shape to confer lasting stability to sites on brain cells, called synapses, that store the memories of a lifetime. \nSurprisingly, the shape-shifting protein in yeast and slugs has all the hallmarks of another protein, the infamous prion, found in humans and other animals. \nSuch prions also assume two shapes. One serves a normal function in the brain. The second sets into motion a runaway process that converts normal prions into a toxic form. As a result, deadly clumps of protein leave holes in the brain and cause disorders like mad cow disease. \nThe disease-causing prion and the memory-storage protein are not identical, said Eric Kandel, a neuroscientist at Columbia Uni-versity who shared the 2000 Nobel Prize in Physiology or Medicine for his research on memory formation. But they share attributes that make prion-like behavior a perfect mechanism for storing memories. \nWith experience and learning, new synapses are formed and others are strengthened, Kandel said. Indeed, mechanisms determining short- and long-term memories are formed have largely been worked out. But questions of how long-term memories are actually stored and what keeps synapses from losing their connectivity under the onslaught of cellular remodeling are outstanding mysteries in biology.
An uncrewed Chinese spacecraft has acquired imagery data covering all of Mars, including visuals of its south pole, after circling the planet more than 1,300 times since early last year, state media reported yesterday. The Tianwen-1 successfully reached the Red Planet in February last year on the country’s inaugural mission there. A robotic rover has since been deployed on the surface as an orbiter surveyed the planet from space. Among the images taken from space were China’s first photographs of the Martian south pole, where almost all of the planet’s water resources are locked. In 2018, an orbiting probe operated by the European
TRADE TALK: Xiao Qian said that Australia had fired the ‘first shot’ in deteriorating trade relations with China, but improvements were possible if Canberra takes action China’s new ambassador to Australia chided protesters who heckled him yesterday during a speech about the future of relations between the two countries. Xiao Qian (肖千), who has only been in the role since January, had just begun his speech at the University of Technology Sydney when the first protesters interjected, calling for freedom for Xinjiang, Tibet and Hong Kong. The ambassador was repeatedly interrupted by sign-wielding protesters, some criticizing China’s treatment of the Uighur people as well as the university for inviting Xiao to speak. “People who are coming again and again to interrupt the process, that’s not expression of freedom of
QUARANTINE SHORTENED: A new protocol detailing risk levels and local policy responses would be ‘more scientific and accurate,’ a health agency spokesman said China’s revised COVID-19 guidelines, which cut a quarantine requirement in half for inbound travelers, also create a standardized policy for mass testing and lockdowns when cases of the disease flare, showing that the country still has a zero-tolerance approach to the virus. Chinese President Xi Jinping (習近平) solidified the position during a trip to Wuhan, where the pathogen first emerged in 2019, saying that China is capable of achieving a “final victory” over the virus. The “zero COVID-19” policy is the most effective and economic approach for the country, Xi said during the trip on Tuesday, Xinhua news agency reported. The first
A former South Korean Navy SEAL turned YouTuber who risked jail time to leave Seoul and fight for Ukraine said it would have been a “crime” not to use his skills to help. Ken Rhee, a former special warfare officer, signed up at the Ukrainian embassy in Seoul the moment Ukrainian President Volodymyr Zelenskiy asked for global volunteers and was fighting on the front lines near Kyiv by early March. To get there, he had to break South Korean law — Seoul banned its citizens from traveling to Ukraine, and Rhee, who was injured in a fall while leading a special operations