New O'Micron variants BA.4 and BA.5 are spreading rapidly in South Africa, faster than BA.2. | Global science news

? Novel coronavirus?

New O'Micron mutants BA.4 and BA.5 are spreading rapidly in South Africa.

New Omicron variants BA.4 and BA.5, first detected by the South African Genome Monitoring Network in mid-December 2021 and January 2022, are spreading rapidly in South Africa, according to Nature's website. According to Science News, from 17 April to 7 May, the number of new cases per day in South Africa increased rapidly from about 1000 to 10,000. At present, these two seed variants have been found in more than a dozen countries (mainly in Europe). BA.4 and BA.5 spread slightly faster than Omicron's BA.2 sublineage, while BA.2 was more contagious than the first Omicron variant BA.1.

Studies have shown that both BA.4 and BA.5 spike proteins carry the amino acid mutation site F486V related to the bond, which may help them block the neutralization reaction of antibodies. On the other hand, BA.4, BA.5 and the Omicron variant BA.2.12.1, which is spreading rapidly on the east coast of the United States, also have a key amino acid mutation site L452Q (also present in the Delta mutant), which is located in the receptor binding domain of the spike protein of the virus, which may help it escape from the attack of the immune system. In addition, another study analyzed the sera of 156 vaccinated and boosted subjects and found that patients infected with the Omicron variant BA.1 had weak ability to neutralize BA.4, BA.5 and BA.2.12.1 in their blood. It is not clear whether BA.4 and BA.5 will increase the hospitalization rate.

? Paleontology?

The longest-tailed swollen dinosaur found in China

Recently, a research team led by researchers from the Institute of Vertebrate Paleontology and Paleoanthropology of the Chinese Academy of Sciences reported on a new genus and species of marine reptiles named Honghesaurus longicaudalis. The fossil was found in the early Middle Triassic marine strata in Luxi County, Honghe Prefecture, Yunnan Province, about 244 million years ago. According to the study, the long-tailed red river dragon has 121 vertebrae, including 69 tail vertebrae, which is the largest known total number of vertebrae and the longest tail (one of the fin dragons). Because the long-tailed red river dragon has a slender trunk and slender limbs, the researchers speculate that it moves mainly through lateral swinging in a shallow sea environment, while an extra-long tail may improve its movement efficiency.

After the mass extinction event at the end of Permian, some reptiles re-entered the ocean and evolved marine reptiles such as ichthyosaurs, ichthyosaurs and fin dragons. The earliest named marine reptile in China belongs to the cladosaurus, which is Keichousaurus hui. The discovery of the long-tailed Honghe dragon is 4 million years earlier than that of Hu's Guizhou dragon, which is the oldest fossil evidence of calylosaurus in China. (science and Technology Daily)

? Environment?

The Tonga volcano eruption affected the upper atmosphere.

In January this year, an undersea volcano in Tonga erupted, triggering a violent explosion and a massive tsunami. The impact of Tonga's volcanic eruption reached Earth's ionosphere, according to a study published recently in the journal KuaiBao of Geophysical Research. The ionosphere refers to the region of the atmosphere that is partially ionized from an altitude of about 60 km to thousands of kilometers. the researchers analyzed data from NASA's ionospheric sounding satellite ICON and the European Space Agency (ESA) swarm (Swarm) satellite and found that severe wind and current disturbances appeared in the ionosphere within hours of Tonga volcano eruption.

The researchers say violent atmospheric fluctuations from volcanic eruptions form strong winds, which are faster in a thinner atmosphere at the top. ICON satellite data show that winds at the top of the ionosphere can reach 724km per hour. At the same time, under the influence of strong ionospheric wind, the charged particles in the ionosphere form an eastward current disturbance, which is called equatorial current collector. Swarm satellite data show that after the Tonga volcano erupted, the equatorial current concentration soared to five times the normal intensity, and there was a brief reverse current concentration to the west. The discovery enhances scientists' understanding of how geological events on the surface affect the ionosphere.

? Physics?

The first three-dimensional quantum spin liquid

Quantum spin liquids have nothing to do with everyday liquids such as water, but with magnets and the way electrons in them rotate. In an ordinary magnet, when the temperature falls below a certain temperature, the electrons will stabilize and form a magnetic solid material. In quantum spin liquids, electrons are unstable when cooled, do not form solids, and are constantly changing and fluctuating, like liquids. In the past, scientists have only realized quantum spin liquids in computer simulations, but in a recent study published in npj Quantum Materials, researchers found evidence of the existence of quantum spin liquids in real materials.

The researchers carried out inelastic neutron scattering experiments on a cerium-zirconium pyrochlore Ce2Zr2O7 and measured the spin-excited continuum at a temperature of 35 nm, which is a sign of quantum spin liquid. Then the researchers use the computer model to calculate the spin dynamics of the material, and obtain a number of key parameters, all of which match the experimental observations. The researchers say the study opens a theoretical understanding of cerium pyrochlore materials and helps physicists understand octupole quantum spin liquids.

? Epidemiology?

Novel coronavirus is a thousand times more likely to spread through the air or a thousand times the contact surface.

Scientists at the University of Michigan used air pumps and swabs to collect samples at different locations on closed campuses between August 2020 and April 2021, according to an article published in the Journal of exposure Science and Environmental Epidemiology. and tested novel coronavirus in the environment. In total, they collected more than 250 air samples, of which 1.6 per cent tested positive for novel coronavirus and 1.4 per cent of the more than 500 surface samples.

Research shows that the most dangerous environment is the gym, where 75% of the air samples and 50% of the surface samples tested positive, of which the water cooler buttons are the most vulnerable to contamination, while the samples taken from the fitness equipment are not positive. In addition, samples taken from office or computer keyboards, light switches, desktops, microwave ovens, refrigerator handles or student desk surfaces are much less likely to be positive. Then, the researchers compared the positive samples with the actual cases of COVID-19 on campus, and found that the probability of infecting novel coronavirus through air transmission was about 100, 000, while the probability of contacting the contaminated surface to infect novel coronavirus was 100, 000. in other words, people are 1000 times more likely to infect novel coronavirus from the air they breathe than from the contact surface. (science and Technology Daily)

? Meteorology?

Climate models overestimate the future rainfall of the Asian-African summer monsoon

Climate forecasting is essential for adaptation and mitigation of climate change. The results of the latest round of International coupled Model comparison Program (CMIP6) have been widely used in climate prediction. However, a new study published in Nature Communications recently suggests that due to biases caused by current global warming, the latest CMIP6 climate model may overestimate future rainfall and runoff of the Asian-African summer monsoon (AfroASM, including the West African, South Asian and East Asian monsoons).

Large-scale monsoon circulation is driven by interhemispheric hot pressure deviation (ITC), and the trend of ITC over the past 30