Accelerator physicists at SLAC have started commissioning the world’s most compact photoinjector – a device that spits out electrons when hit by light. Photoinjectors are used to generate electrons for free-electron lasers (FELs) like the Linac Coherent Light Source, among other things, and this development could enable much more compact FELs, as well as other types of accelerator-based facilities. The device is just one facet of X-band research at SLAC, which aims to find ways to accelerate electrons with “X-band” microwaves rather than the S-band waves that currently boost electrons in the linear accelerator to relativistic speeds....

Researchers from the Universities of Warwick, Cambridge, and Fudan University analyzed neuroimaging data from more than 30,000 adults in the UK Biobank data set to examine how social isolation and loneliness were connected to eventual dementia. The gray matter volumes of the parts of the brain responsible for memory and learning were shown to be lower in socially isolated people. The findings of the study were recently published in the journal Neurology....

Seeking a view of the Sun’s north and south poles, Solar Orbiter will journey out of the ecliptic plane — the belt of space, roughly in line with the Sun’s equator, through which the planets orbit. Slinging repeatedly past Venus in order to draw near the Sun and climb higher above the ecliptic, the spacecraft bounds from the Sun and back toward the orbit of Earth throughout its mission. “Although Solar Orbiter goes quite close to the Sun, it also goes quite far away,” said Anne Pacros, the payload manager at the European Space Agency’s, or ESA’s, European Space Research and Technology Centre in the Netherlands....

For more information about the launch, read on. A SpaceX Dragon cargo spacecraft is on its way to the International Space Station after launching at 12:29 p.m. EST December 5, 2019. Dragon will deliver more than 5,700 pounds of NASA cargo and science investigations, including studies of malting barley in microgravity, the spread of fire, and bone and muscle loss. The spacecraft launched on a Falcon 9 rocket from Space Launch Complex 40 at Cape Canaveral Air Force Station in Florida and is scheduled to arrive at the orbital outpost on Sunday, December 8....

Woolly mammoths were one of the most abundant, cold-adapted species on earth before the conclusion of the Pleistocene (~11,700 years ago). The end of this period was marked by dramatic climate fluctuations that eventually gave way to Holocene — which saw the near complete loss of cold and dry steppe tundra, (also known as the Mammoth steppe). This change caused the extinction of many species, including cave bears, cave hyenas, the woolly rhinoceros, and the continental population of woolly mammoths....

The precise regulation of cerebral blood flow is critical for normal brain function, and its disruption underlies many neuropathologies. Using optical imaging, researchers from Yale University found that capillary pericytes in mice and humans do not express smooth muscle actin and are morphologically and functionally distinct from adjacent precapillary smooth muscle cells (SMCs). An investigation of blood flow network in the brain has revealed some surprising behavior of vessels during stroke, according to Yale researchers....

A SpaceX Falcon 9 rocket stands poised for liftoff at Vandenberg Space Force Base’s Space Launch Complex-4 East in California, ready to send SWOT on the first mission to observe nearly all water on the Earth’s surface. NASA’s Launch Services Program, based at the agency’s Kennedy Space Center in Florida, is managing the launch. This will be LSP’s 42nd primary mission to launch from Vandenberg, and the program’s 101st full end-to-end mission....

University of Bristol paleontologist Professor Mike Benton identifies in the journal Gondwana Research that the ancestors of both mammals and birds became warm-blooded at the same time, some 250 million years ago, in the time when life was recovering from the greatest mass extinction of all time. The Permian-Triassic mass extinction killed as much as 95 percent of life, and the very few survivors faced a turbulent world, repeatedly hit by global warming and ocean acidification crises....

Liquid water is indispensable for life as we know it, yet many of its properties do not conform with the way other fluids behave. Some of these anomalies, such as water’s maximum density at 4°C and its large heat capacity, have important implications for living organisms. The origin of these features has sparked fierce debates in the scientific community since the time of Röntgen. Now, researchers at The University of Tokyo have utilized a two-state model that posits the dynamical coexistence of two types of molecular structures in liquid water....

The researchers found that, in aging, there is an overload of the protein SPT and others, all of which are needed to convert fatty acids and amino acids to ceramides. “The sphingolipids and ceramides are complex yet very interesting fat class, and there is high potential to further study their role in aging, as they perform many diverse functions,” says Dr. Pirkka-Pekka Laurila, a medical doctor and the lead author of the study....

The space between stars is not empty. It contains copious but diffuse amounts of gas and dust. In fact, about 5-10% of the total mass of our Milky Way galaxy is in interstellar gas. About 1% of the mass of this interstellar material, quite a lot in astronomical terms, is in the form of tiny dust grains made predominantly of silicates (sand too is made of silicates), though some grains are also composed of carbon and other elements....

The scientists published their findings in the Proceedings of the Royal Society B: Biological Sciences.[1] Training with backward running is quite different than usual running. As expected, it was discovered that runners struck the ground near the back of their feet when going forward, and rolled onto the front of their feet for takeoff. When they were going backward, they landed near the front of their feet and took off from the heels....

Predator and prey maintain a close relationship to each other: if one evolves, the other must keep pace. Such coevolution and its accompanying selection pressure lead to mutual adaptation of the two species. In their experiments, Lutz Becks and his fellow Plön-based researchers from Plön, London, and Finland held bacteria and ciliates together for many weeks and traced their evolution. Here, they observed how the microbes protect themselves against the gluttony of the ciliates when, after a few days, the bacterial cells, normally living in isolation, began to grow in larger associations as a slimy “biofilm....

According to new research from Cornell University, Johns Hopkins University, and international partners, the United States food production could reduce its agricultural carbon footprint by between 2.5% and 13.5% by embracing meat protein alternatives, primarily by reducing the number of cows required for beef production by two to 12 million. The researchers noted that although taking steps to slow climate change is important, technology disruption may have a variety of economic repercussions, both good and bad, affecting issues like livelihoods, working conditions, human rights, fair wages, and health equity....

The United States may have set itself up for the spread of a pandemic without even knowing it. According to new research from the McKelvey School of Engineering at Washington University in St. Louis, pollution may bear part of the blame for the rapid proliferation in the United States of SARS-CoV-2, the virus responsible for the spread of COVID-19. The research, from the lab of Rajan Chakrabarty, associate professor in the Department of Energy, Environmental & Chemical Engineering, was published online ahead of print in the journal Science of The Total Environment....

One survivor — a 20-year-old Marine — recounted seeing shark fins swimming around them, hearing blood-curdling screams, watching bodies get sucked under, and seeing empty life vests pop back up to the surface. It’s impossible to know how many died by shark attack but rough estimates range from a few dozen to 150 people. Many consider this the largest shark attack in history. And it took a toll on Navy morale....

Researchers call for routine monitoring of vaccine effectiveness as the COVID-19 pandemic continues to evolve. mRNA vaccines are highly effective in preventing COVID-19 associated hospital admissions related to the alpha, delta, and omicron variants. But three doses are needed to achieve a similar level of protection against omicron that two doses provide against the delta and alpha variants, finds a large US study published by The BMJ today (March 9, 2022)....

The answer to that question has long eluded scientists, but new research from McGill University has uncovered a molecular mechanism that may be a key piece of the puzzle. The discovery could provide new targets for treating a wide range of diseases. Fighting off infections depends largely on our bodies’ capacity to quickly recognize infected cells and destroy them, a job carried out by a class of immune cells known as CD8+ T cells....

Now researchers led by Penn biologist Joshua B. Plotkin and the University of Houston’s Alexander J. Stewart have identified another impediment to democratic decision-making, one that may be particularly relevant in online communities. In what the scientists have termed “information gerrymandering,” it’s not geographical boundaries that confer a bias but the structure of social networks, such as social media connections. Reporting in the journal Nature, the researchers first predicted the phenomenon from a mathematical model of collective decision-making, and then confirmed its effects by conducting social network experiments with thousands of human subjects....