Nearly 42,000 years ago, when Earth's magnetic fields reversed, this triggered major environmental changes, extinction events, and long-term changes in human behavior, a new study reports. The findings, made possible by a new radiocarbon record derived from New Zealand's ancient kauri trees, raise important questions about the evolutionary impacts of geomagnetic reversals and excursions throughout the deeper geological record, the authors say. "Before this work," says author Chris Turney in a related video, "we knew there were a lot of things happening around the world at 42,000 years ago, but we didn't know precisely how... For the first time, we've been able to precisely date what happened when Earth's magnetic fields last flipped." Written in the geological ...

Few of Earth's freshwater areas remain untouched by humans. More than half of the planet's freshwater river basins have been heavily impacted by human activities, according to a new study, which presents a novel, multi-faceted approach for evaluating biodiversity change at a global scale. Although rivers and lakes cover less than 1% of the planet's surface, they support a substantial component of the planet's biodiversity, including a quarter of Earth's vertebrates. Further, freshwater systems support the functioning and stability of a variety of ecosystems, including those that contribute to human wellbeing. Centuries of human activity - overfishing, non-native species introductions, on-river development, ...

Scientists have used a technique to grow bile duct organoids - often referred to as 'mini-organs' - in the lab and shown that these can be used to repair damaged human livers. This is the first time that the technique has been used on human organs. The research paves the way for cell therapies to treat liver disease - in other words, growing 'mini-bile ducts' in the lab as replacement parts that can be used to restore a patient's own liver to health - or to repair damaged organ donor livers, so that they can still be used for transplantation. Bile ducts act as the liver's waste disposal system, and malfunctioning bile ducts are behind a third of adult and 70 per cent of children's liver transplantations, with no ...

Organoids grown from bile duct epithelial cells can be used to repair damaged bile ducts in transplanted human livers, researchers report. The results provide proof of concept for using ex vivo cell-based therapy to improve organ function before transplantation, which could ultimately increase the number of useable organs on the transplant waiting list. Bile produced in the liver is carried to the small intestine through a network of bile ducts formed by biliary epithelial cells known as cholangiocytes. While crucial for digestion, bile becomes toxic when it accumulates in the liver. As a result, chronic liver diseases that affect cholangiocytes often result in liver failure ...

CAMBRIDGE, MA -- Bacteria have many ways to evade the antibiotics that we use against them. Each year, at least 2.8 million people in the United States develop an antibiotic-resistant infection, and more than 35,000 people die from such infections, according to the U.S. Centers for Disease Control. Most of the mutations known to confer resistance occur in the genes targeted by a particular antibiotic. Other resistance mutations allow bacteria to break down antibiotics or pump them out through their cell membranes. MIT researchers have now identified another class of mutations that helps bacteria develop resistance. In a study of E. coli, they discovered that mutations to genes involved ...

The temporary breakdown of Earth's magnetic field 42,000 years ago sparked major climate shifts that led to global environmental change and mass extinctions, a new international study co-led by UNSW Sydney and the South Australian Museum shows. This dramatic turning point in Earth's history - laced with electrical storms, widespread auroras, and cosmic radiation - was triggered by the reversal of Earth's magnetic poles and changing solar winds. The researchers dubbed this danger period the 'Adams Transitional Geomagnetic Event', or 'Adams Event' for short - a tribute to science fiction writer Douglas Adams, who wrote in The Hitchhiker's Guide to the Galaxy that '42' was the answer to life, the universe, and everything. The findings are published today ...

"For decades, chemistry has been governed by two ambitions goals," says Professor Stefan Tautz, head of the Quantum Nanoscience subinstitute at END ...

Cygnus X-1, a binary star system first discovered in 1964, comprises one of the closest black holes to Earth. New observations of this black hole, the first ever detected, have led astronomers to question what they know about the Universe's most mysterious objects. An international team, including researchers from the National Astronomical Observatories of the Chinese Academy of Sciences (NAOC), recently found that the stellar-mass black hole in the Cygnus X-1 binary system has a mass 21 times the mass of the Sun and rotates at a speed close to the speed of light. The study was published in Science on Feb. 18. The researchers used the Very Long Baseline Array - a continent-sized radio ...

Engineers have developed a technique that allows them to precisely place microscopic devices formed from folded DNA molecules in not only a specific location but also in a specific orientation. As a proof-of-concept, they arranged more than 3,000 glowing moon-shaped nanoscale molecular devices into a flower-shaped instrument for indicating the polarization of light. Each of 12 petals pointed in a different direction around the center of the flower, and within in each petal about 250 moons were aligned to the direction of the petal. Because each moon only glows when struck by polarized light matching its orientation, the end result is a flower whose petals light up in sequence as the polarization of light shined upon it is rotated. The flower, which ...

Inhibitors based on approved drugs and designed to disrupt the SARS-CoV-2 viral protein Mpro display strong antiviral activity both in vitro and in a transgenic mouse model, a new study reports. While vaccines are an important tool in the fight against COVID-19, it remains a high priority to develop antiviral drugs, especially with the rise of variants that may partially evade vaccines. The viral protein Mpro is a protease that is required for cleaving precursor polyproteins into functional viral proteins. This essential function makes it a key drug target. Jingxin Qiao et al. designed 32 ...

The COVID-19 pandemic's heavy toll on older Americans highlights the need to strengthen the nation's safety net for people in need of long-term services and supports, an Oregon Health & Science University researcher and co-authors argue in a new report published by Milbank Quarterly. The report proposes a system of universal coverage to support the long-term care of all older Americans. "This approach would protect against financial catastrophe and end the current system that is based on the need to be financially destitute in order to access coverage via Medicaid," ...

BOSTON -- COVID-19, the source of the current pandemic, may be caused by a single virus, but it has a variety of presentations that make treatment difficult. Children, for example, almost exclusively experience mild or asymptomatic COVID-19, while adults can develop severe or even fatal COVID-19. But children who contract COVID-19 are at risk for a rare but serious syndrome called multisystem inflammatory syndrome in children (MIS-C). Severe cases of MIS-C can lead to cardiac disease and ventricular failure, and require hospitalization and intense medical support. Researchers Galit Alter, PhD, core member of the Ragon Institute of MGH, MIT and Harvard, and Lael Yonker, MD, ...

The effects of selective serotonin reuptake inhibitors (SSRIs) and other conventional antidepressants are believed to be based on their increasing the levels of serotonin and noradrenalin in synapses, while ketamine, a new rapid-acting antidepressant, is thought to function by inhibiting receptors for the neurotransmitter glutamate. Neurotrophic factors regulate the development and plasticity of the nervous system. While all antidepressants increase the quantity and signalling of brain-derived neurotrophic factor (BDNF) in the brain, the drugs have so far been thought to act on BDNF indirectly, through serotonin or glutamate receptors. A new study published this week in Cell demonstrates, however, that antidepressants bind directly to a BDNF receptor known as TrkB. This finding challenges ...

NEW YORK, NY (Feb. 18, 2021)--A new study from Columbia University Vagelos College of Physicians and Surgeons has found that suicide mortality can be reduced by a Federally coordinated approach employing scientifically proven options. Columbia researchers J. John Mann, MD, Christina A. Michel, MA, and Randy P. Auerbach, PhD, conducted a systematic review, determining which suicide prevention strategies work and are scalable to national levels. The study, "Improving Suicide Prevention Through Evidence-Based Strategies: A Systematic Review," was published online in the American Journal of Psychiatry. The researchers found that screening school children or the general population for those at risk for suicide--the ...

While the human brain has over 400 miles of total vasculature, little is known about the tiny capillaries that make up much of this intricate labyrinth of blood vessels critical for delivering oxygenated blood and nutrients to billions of brain cells. According to Dr. Andy Shih, a principal investigator in the Center for Developmental Biology and Regenerative Medicine at Seattle Children's Research Institute, understanding how this vast network regulates blood flow in the brain could hold the key to new treatments for neonatal and childhood neurologic conditions, such as stroke and hypoxia, and issues of aging like dementia and Alzheimer's disease. "Insufficient blood flow contributes to many of the common neurologic problems seen in children and adults," he said. "Yet, ...

Acres of asphalt parking lots, unshaded roads, dense apartment complexes and neighborhoods with few parks have taken their toll on the poor. As climate change accelerates, low-income districts in the Southwestern United States are 4 to 7 degrees hotter in Fahrenheit -- on average -- than wealthy neighborhoods in the same metro regions, University of California, Davis, researchers have found in a new analysis. This study provides the most detailed mapping yet of how summer temperatures in 20 urban centers in California, Nevada, Utah, Arizona, Colorado, New Mexico and Texas affected different neighborhoods between 2018 and 2020. The researchers found even greater heat disparities in California than in other states. The largest disparities showed ...

PHILADELPHIA (February 18, 2021) - With stressors mounting daily on the health care system due to the COVID-19 pandemic, a de-prioritization of the childbearing family has been noted. Their care has changed, resulting in mothers forced to go through labor and birth without their partners, parents barred from NICU visitation, and discharge of mothers and newborns early without enough expert lactation care. There is great concern that these changes in childbearing families' care may become permanent - to the detriment of the health of both mother and ...

American values, attitudes and activities have changed dramatically during COVID-19, according to a new study of online behavior. Researchers from UCLA and Harvard University analyzed how two types of internet activity changed in the U.S. for 10 weeks before and 10 weeks after March 13, 2020 -- the date then-President Donald Trump declared COVID-19 a national emergency. One was Google searches; the other was the phrasing of more than a half-billion words and phrases posted on Twitter, blogs and internet forums. The study is the lead research article in a special issue of the journal Human Behavior and Emerging Technologies ...

ORLANDO, Feb. 18, 2021 - University of Central Florida researchers are homing in on the cause of a major disease of sea turtles, with some of their latest findings implicating saltwater leeches as a possible factor. The disease, known as fibropapillomatosis, or FP, causes sea turtles to develop tumors on their bodies, which can limit their mobility and also their health by interfering with their ability to catch and eat prey. While the cause of FP isn't known, saltwater leeches have been suspected to play a role due to their frequent presence on areas of sea turtles where FP tumors often develop, such as on their eyes, mouths and ...

MALVERN, Pa. -- Doctors and healthcare workers may one day use a machine learning model, called deep learning, to guide their treatment decisions for lung cancer patients, according to a team of Penn State Great Valley researchers. In a study, the researchers report that they developed a deep learning model that, in certain conditions, was more than 71 percent accurate in predicting survival expectancy of lung cancer patients, significantly better than traditional machine learning models that the team tested. The other machine learning models the team ...

HOUSTON -- The first randomized Phase II clinical trial to report on single and combined neoadjuvant immune checkpoint inhibitor therapy in stage I-III non-small cell lung cancer (NSCLC) found combination therapy produced a significant clinical benefit, as assessed by major pathologic response (MPR) rate, as well as enhanced tumor immune cell infiltration and immunological memory. Researchers from The University of Texas MD Anderson Cancer Center published the study results today in Nature Medicine. The NEOSTAR trial tested combined neoadjuvant therapy of nivolumab plus ipilimumab, as well as neoadjuvant nivolumab monotherapy in patients with operable NSCLC. The trial met its prespecified primary endpoint efficacy threshold in ...

Throughout nature, there are instances of animals aiding one another and living together in mutually beneficial relationships that have helped shape the world's landscapes and biodiversity. These domesticator-domesticate relationships form when one species provides multigenerational support to another species in exchange for a resource or service that benefits both species. An example of this type of relationship is how early humans domesticated gray wolves. The wolves were attracted to the human encampments, which provided them with protection and resources, and the wolves, in turn, helped the humans increase their hunting proficiency. One area ...

Richer countries were more likely to see rates of COVID-19 fall faster during the first wave of the pandemic, according to new research published in the journal Frontiers in Public Health. The study by Anglia Ruskin University (ARU) professors Shahina Pardhan and Nick Drydakis examined economic indicators in 38 European countries, such as Gross Domestic Product (GDP) per capita, life expectancy, and public spending, and the number of new coronavirus cases per million of the population between 1 April and 31 May 2020, using data from Our World in Data based on the seven-day rolling average of new cases for each country. A significant negative correlation ...

UCLA RESEARCH ALERT FINDINGS UCLA Jonsson Comprehensive Cancer Center researchers have uncovered a potential new way to target pancreatic tumors that express high intratumoral interferon signaling (IFN). The team found that high type I IFN signaling is present in a subset of pancreatic tumors and it triggers a decrease in the level of NAD and NADH in pancreatic cancer cells, which are vital cofactors in critical metabolic processes. After the researchers delineated the mechanism by which the NAD depletion occurs, they demonstrated that cells with high IFN signaling were more sensitive to NAMPT inhibitors, which inhibit a major pathway ...

NEW YORK, NY (Feb. 18, 2021)--A research team at the Center of Prevention and Evaluation (COPE) at Columbia University Irving Medical Center and the New York State Psychiatric Institute, led by Drs. Gary Brucato and Ragy R. Girgis, found that, contrary to popular belief, serious mental illness was present in only 11% of all mass murderers and in only 8% of mass shooters. The study--the first published report on mass shootings from the Columbia Mass Murder Database--appeared online Feb. 17th in Psychological Medicine. The investigators sought to gain much-needed insight into the relationship between serious mental ...