Posts

Astronomers have discovered more than 200 distant variable stars known as RR Lyrae stars in the Milky Way’s stellar halo. The most distant of these stars are more than a million light-years from Earth, almost half the distance to our neighboring galaxy, Andromeda, which is about 2.5 million light-years away. The characteristic pulsations and brightness of RR Lyrae stars make them excellent “standard candles” for measuring galactic distances. These new observations allowed the researchers to trace the outer limits of the Milky Way’s halo....

On April 27, a blast of light from a dying star in a distant galaxy became the focus of astronomers around the world. The explosion, known as a gamma-ray burst and designated GRB 130427A, tops the charts as one of the brightest ever seen. A trio of NASA satellites, working in concert with ground-based robotic telescopes, captured never-before-seen details that challenge current theoretical understandings of how gamma-ray bursts work. This animation shows the most common type of gamma-ray burst, thought to occur when a massive star collapses, forms a black hole, and blasts particle jets outward at nearly the speed of light....

The first experimental observation of a quantum mechanical phenomenon that was predicted nearly 70 years ago holds important implications for the future of graphene-based electronic devices. Working with microscopic artificial atomic nuclei fabricated on graphene, a collaboration of researchers led by scientists with the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California (UC) Berkeley have imaged the “atomic collapse” states theorized to occur around super-large atomic nuclei....

47 studies were included in the analysis, which was published in the Journal of the American Geriatrics Society. A 23% greater likelihood of cognitive decline and a 21% higher risk of dementia was linked to poor periodontal health (indicated by periodontitis, tooth loss, deep periodontal pockets, or alveolar bone loss). Tooth loss alone was associated with a 23% increased risk of cognitive deterioration and a 13% increased chance of dementia....

Infectious diseases spilling over from wildlife are not new — as of 2008, approximately 70 percent of all known emerging diseases are thought to have originated from wild animals. In the last 50 years, several viruses, such as Ebola, Marburg, Severe Acute Respiratory Syndrome (SARS), Hendra, swine flu, and Nipah have appeared in areas with close human-animal contact. Tropical areas where hunted wildlife often supplements the locals’ meager diets — such as in Africa, South and Southeast Asia — are hotspots for pathogen spillovers....

Researchers published their findings in the journal PLoS ONE. During pregnancy, mammal mothers and fetuses exchange DNA as well as cells. Previous work has shown that fetal cells can linger in a mother’s blood and bone for decades. This is called fetal microchimerism. This lingering fetal DNA could benefit the mother’s health, by promoting tissue repair and improving the immune system, but it may also cause adverse effects, such as autoimmune reactions....

Researchers at The Ohio State University found that children with bipolar disorder had higher blood levels of a protein associated with vitamin D compared to children without mood disorders. Finding a blood test to confirm bipolar disorder could improve care and cut the current 10-year average lag time between onset and diagnosis, said Ouliana Ziouzenkova, the study’s lead author and an associate professor of human nutrition at Ohio State. In the study of 36 young people, levels of the vitamin D binding protein were 36 percent higher in those with bipolar disorder than in those without a mood disorder....

The brain’s ability to clear a protein closely linked to Alzheimer’s disease is tied to our circadian cycle, according to research published recently in PLOS Genetics. The research underscores the importance of healthy sleep habits in preventing the protein Amyloid-Beta 42 (AB42) from forming clumps in the brain, and opens a path to potential Alzheimer’s therapies. “Circadian regulation of immune cells plays a role in the intricate relationship between the circadian clock and Alzheimer’s disease,” said Jennifer Hurley, an expert in circadian rhythms, and associate professor of biological science at Rensselaer Polytechnic Institute....

Researchers at Yale were able to profile for the first time both microRNA and messenger RNA (mRNA) in the same individual cell. By doing so, they discovered new mechanisms that lead to the heterogeneity – that is, the many variations – of gene expression. The results are published today in Nature Communications. The research is a collaboration between the laboratories of Rong Fan, associate professor of biomedical engineering, and Jun Lu, an associate professor of genetics at the Yale Stem Cell Center....

Study in Science of more than 780,000 Veterans is the first to compare waning protection rates across all three vaccine types available to most Americans and to directly report death rates after breakthrough infection. A new study in the leading journal Science reviewed COVID-19 breakthrough infections among 780,225 Veterans, finding that vaccine protection declined from 87.9% to 48.1% during the 2021 Delta surge in the U.S. The researchers from PHI, the Veterans Affairs Medical Center and the University of Texas Health Science Center found a dramatic decline in effectiveness for the Janssen (Johnson and Johnson) vaccine, from 86....

A new strategy to reduce the spread of COVID-19 employs a mobile robot that detects people in crowds who are not observing social-distancing rules, navigates to them, and encourages them to move apart. Adarsh Jagan Sathyamoorthy of the University of Maryland, College Park, and colleagues present these findings in the open-access journal PLOS ONE on December 1, 2021. Previous research has shown that staying at least two meters apart from others can reduce the spread of COVID-19....

But as computing and information processing microdevices get ever smaller and more powerful, they are running into some fundamental limits imposed by the laws of quantum physics. Because of this, the future of the field may lie in photonics—the light-based parallel to electronics. Photonics is theoretically similar to electronics but substitutes photons for electrons. They have a huge potential advantage in that photonic devices may be capable of processing data much faster than their electronic counterparts, including for quantum computers....

However, key aspects of touch, such as how the spinal cord and brainstem are involved in receiving, processing, and transmitting signals, remain unknown. Now, two studies from Harvard Medical School researchers provide significant new understandings of how the spinal cord and brainstem contribute to the sense of touch. The study found that the spinal cord and brainstem, which were previously assumed to just be relay centers for touch information, are actively engaged in the processing of touch signals as they travel to higher-order brain regions....

A new study has revealed how fast some distant, rapidly growing supermassive black holes are spinning.The material around of one these black holes is spinning at greater than about 70% of the speed of light.Astronomers used Chandra to study the accretion disks of material around the black holes that are superheated and glow in X-rays.The researchers used gravitational lensing that produces multiple images of a background object due to the bending of space-time....

Platinum works well as a catalyst in hydrogen fuel cells, but it has at least two drawbacks: It is expensive, and it degrades over time. Brown chemists have engineered a cheaper and more durable catalyst using graphene, cobalt, and cobalt-oxide — the best nonplatinum catalyst yet. There’s a new contender in the race to find an inexpensive alternative to platinum catalysts for use in hydrogen fuel cells. Brown University chemist Shouheng Sun and his students have developed a new material — a graphene sheet covered by cobalt and cobalt-oxide nanoparticles — that can catalyze the oxygen reduction reaction nearly as well as platinum does and is substantially more durable....

“This is the first paper documenting induction/stimulation of pollen germination by non-plants,” said Christensen, a doctoral candidate in the Microbiology Graduate Group who joined the Vannette lab in January 2019. “Nectar-dwelling Acinetobacter bacteria, commonly found in flowers, stimulate protein release by inducing pollen to germinate and burst, benefitting Acinetobacter.” The article, “Nectar Bacteria Stimulate Pollen Germination and Bursting to Enhance Microbial Fitness,” is online and will be in print in the October 11th edition of the journal Current Biology....

Clonidine, a medication commonly used to treat high blood pressure and attention deficit hyperactivity disorder (ADHD), is also being explored as a potential treatment for post-traumatic stress disorder (PTSD). This is because clonidine acts on adrenergic receptors in the brain, best known for their key role in the “fight or flight” response, a heightened state of awareness that helps protect us in dangerous situations. These receptors are thought to be activated in PTSD and to have a role in consolidating a traumatic memory....

Researchers at the Department of Microbiology of The University of Hong Kong (HKU) have found that the COVID19 virus can cause acute testicular damage, chronic asymmetric testicular atrophy, and hormonal changes in hamsters despite a light pneumonia. “In managing convalescent COVID-19 males, it is important to be aware of possible hypogonadism (low sex drive) and subfertility,” said Chair of Infectious Diseases Professor Kwok-yung Yuen, who led the research effort. “COVID-19 vaccination can prevent this complication....

Cislunar Autonomous Positioning System Technology Operations and Navigation Experiment (CAPSTONE) is a microwave oven-sized satellite, weighing just 55 pounds, that will be the first CubeSat to fly to and operate at the Moon. It serves as a pathfinder for Gateway, a Moon-orbiting space station that is part of NASA’s Artemis program. CAPSTONE’s mission will help reduce risk for future spacecraft, including Orion, by validating innovative navigation technologies and verifying the dynamics of a type of halo-shaped orbit that has never been flown before....

NASA’s Mars Rover Curiosity on Sol 82 (October 29, 2012) used its Mars Hand Lens Imager (MAHLI) to photograph the diverse rocks in the “Rocknest” area and prepared for an overnight analysis of a soil sample by the Chemistry and Mineralogy (CheMin) instrument. On the preceding sol, the rover completed its third round of using vibration of scooped Martian soil to scrub the interior surfaces of the sample-processing mechanisms on the rover’s arm....