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The miniature size of the device is possible due to the short wavelength of terahertz radiation. “Terahertz-based accelerators have emerged as promising candidates for next-generation compact electron sources,” explains Franz Kärtner, Lead Scientist at DESY and head of the CFEL group that built the device. Scientists have successfully experimented with terahertz accelerators before, which could enable applications where large particle accelerators are just not feasible or necessary. “However, the technique is still in an early stage, and the performance of experimental terahertz accelerators has been limited by the relatively short section of interaction between the terahertz pulse and the electrons,” says Kärtner....

Researchers used gene editing to turn off a specific molecule in the plant’s genome which increased provitamin D3 in both the fruit and leaves of tomato plants. It was then transformed into vitamin D3 through exposure to UVB light. Vitamin D is created in our bodies after our skin is exposed to UVB light, but the major source is food. This new biofortified crop could help millions of people with vitamin D insufficiency, a growing issue linked to an increased risk of cancer, dementia, and many leading causes of mortality....

Some areas of the adult brain contain quiescent, or dormant, neural stem cells that can potentially be reactivated to form new neurons. However, the transition from quiescence to proliferation is still poorly understood. A team led by scientists from the Universities of Geneva (UNIGE) and Lausanne (UNIL) has discovered the importance of cell metabolism in this process and identified how to wake up these neural stem cells and reactivate them....

Professor Kyong-Tai Kim and Ph.D. candidate Kyung Won Jo, from the Department of Life Sciences at the Pohang University of Science & Technology (POSTECH), have found that the gossypetin in hibiscus activates microglia, the immune cells in the brain. Their research also showed that these microglia can scavenge amyloid-beta in the brain to improve cognitive function in individuals with Alzheimer’s disease. AD begins as Aβ and Tau protein aggregates form deposits in the brain tissue....

An international team of researchers, led by Philippe Schmitt-Kopplin from the Technical University of Munich and Helmholtz Munich and including Andrew Steele from Carnegie, has discovered a vast diversity of organic compounds in the Martian meteorite Tissint. Their findings have recently been published in the journal Science Advances. Tissint, a Martian meteorite that impacted Earth over 11 years ago and crash-landed in Morocco, is one of only five such meteorites that have been observed while falling to our planet....

Suppose in front of you there is a container filled with an unknown liquid. Your goal is to find out by how much the particles in it (atoms or molecules) move back and forth randomly due to their thermal energy. However, you do not have a microscope with which you could visualize these position fluctuations known as “Brownian motion”. It turns out you do not need that at all: You can also simply tie an object to a string and pull it through the liquid....

The research group observed that the greenhouse gas nitrous oxide is released into the atmosphere not only by the forest soil, but also by pine, birch, and spruce, the trees of the northern boreal zone. The group has previously demonstrated (Machacova et al., 2016; Scientific Reports) that the stems and canopies of pine trees in the northern boreal zone are sources of N2O. This recent study indicated that also birches and spruces release the gas into the atmosphere....

Cancer cells produce large numbers of exosomes, which contribute to tumor progression in many different ways. They can transfer cancer-causing oncogenes to neighboring cells to increase their proliferation; they can contain proteins that reorganize the cancer cells’ surroundings and allow them to spread to other tissues; and they can contain signaling factors that disrupt the body’s ability to mount an immune response against the tumor. A team led by Thomas F....

Cells like to stick together and no matter how hard he tried, he could never ensure that he had a single cell to work with. Eventually, he started using chemicals to dissolve the outer layers of cells and release the nuclei. Then, the nuclei were separated using an automated cell sorter and their DNA was extracted. This process was repeated for 100 cells and the obtained sequences revealed how the tumor had evolved from a few rogue cells into a complex mixture of genetically distinct ones....

Australians desperate for solutions to raging wildfires might find them 8,000 miles (13,000 kilometers) away, where a new Stanford-led study proposes ways of overcoming barriers to prescribed burns – fires purposefully set under controlled conditions to clear ground fuels. The paper, published on January 20, 2020, in Nature Sustainability, outlines a range of approaches to significantly increase the deployment of prescribed burns in California and potentially in other regions, including Australia, that share similar climate, landscape, and policy challenges....

The nutrient, called ergothioneine or EGT, is an antioxidant that protects bacteria from oxidative stress — an imbalance in the body between reactive oxygen species, known as free radicals, and antioxidants — which is a hallmark of many disease-causing infections. These findings may provide insights into the development of new drugs to combat a range of infectious diseases in humans. When the immune system produces oxygen-containing molecules called free radicals to kill harmful bacteria, it can lead to an imbalance in the body known as oxidative stress....

A computer simulation suggests that there are many single stars that were born as two separate suns, which eventually merged into a single star during the first million years of their existence. The scientists published their findings in the journal Astronomy and Astrophysics. Double stars, like Sirius, are quite common. Studies of star-forming regions suggest that binary stars start off with a uniform distribution of orbital periods – the number of binaries younger than a few million years that orbit each other every 1–10 years, 10–100 years, 100–1,000 years, and so on, is about the same, – but older binaries show a different pattern....

Most American children receive recommended vaccines protecting them from dangerous illnesses like measles and whooping cough. But doctors sometimes care for children whose parents refuse vaccines against providers’ recommendations. And that is not news many parents of vaccinated children want to hear, suggests the C.S. Mott Children’s Hospital National Poll on Children’s Health at the University of Michigan. Three in 10 parents polled say that their child’s primary care office should ask parents who refuse all vaccines to find another health provider....

The group led by Professor Martina Havenith, Chair of Physical Chemistry II, and Professor Dominik Marx, Chair of Theoretical Chemistry, from Ruhr-Universität Bochum, together with the team led by Dr. Britta Redlich from Radboud University, Nijmegen, describes the results in the journal Science Advances, published online in advance on 7 June 2019. Understanding how complex molecules were formed If hydrochloric acid comes into contact with water molecules under normal conditions, such as at room temperature, the acid immediately dissociates: it releases its proton (H+), one chloride ion (Cl-) remains....

The molecule, dubbed NGI-1, was identified by co-author Joseph Contessa, M.D., an associate professor of therapeutic radiology and of pharmacology at Yale School of Medicine. In collaboration with Stanford researchers, Contessa’s team investigated whether NGI-1 could prevent replication of the viruses in host cells. In experiments, the research team infected human cells with either dengue or Zika viruses and treated the cells with NGI-1. They found that the molecule treatment significantly limited replication of the viruses as well as infection in cells....

Atmospheric pollution is a growing problem, particularly in urban areas and in less developed countries. According to the World Health Organization, one out of every nine deaths can be attributed to diseases caused by air pollution. Organic pollutants, such as nitrogen oxides and volatile compounds, are the main cause of this, and they are mostly emitted by vehicle exhausts and industry. To address the problem, researchers are continually on the hunt for new ways to remove more pollutants from the atmosphere, and photocatalysts such as titania are a great way to do this....

More than 50 species of tree snail in the South Pacific Society Islands were wiped out following the introduction of an alien predatory snail in the 1970s, but the white-shelled Partula hyalina survived. Now, thanks to a collaboration between University of Michigan biologists and engineers with the world’s smallest computer, scientists understand why: P. hyalina can tolerate more sunlight than its predator, so it was able to persist in sunlit forest edge habitats....

With the spacecraft on its path home, the astronauts will settle in for an eight-hour sleep period. While they’re asleep, a six-minute departure phasing burn at 1:48 a.m. Sunday, August 2 will set the Dragon Endeavour on the proper orbital path to a planned splashdown in the Gulf of Mexico off the coast of Pensacola, Florida. NASA’s live coverage of the crew’s return home to Earth continues through the night....

Jupiter’s atmosphere is famous for its characteristic multicolored vortices. However, it is also unexpectedly hot. In fact, it is hundreds of degrees hotter than models predict. After all, the giant planet receives under 4% of the amount of sunlight compared to Earth, due to its orbital distance of 483 million miles (778 million km) from the Sun. Therefore its upper atmosphere should theoretically be a frigid -70 degrees Celsius (-100 degrees Fahrenheit)....

Watching starbirth isn’t easy: tens of millions of years are needed to form a star like our Sun. Much like archeologists who reconstruct ancient cities from shards of debris strewn over time, astronomers must reconstruct the birth process of stars indirectly, by observing stars in different stages of the process and inferring the changes that take place. Studies show that half of the common stars, including our Sun, formed in massive clusters, rich with young stars, from which they eventually escape....