The giant impact believed to have formed the Earth-Moon system has long been accepted as canon. However, a major challenge to the theory has been that the Earth and Moon have identical oxygen isotope compositions, even though earlier impact models indicated they should differ substantially. In a paper published today in the journal Science online, a new model by Southwest Research Institute (SwRI), motivated by accompanying work by others on the early dynamical history of the Moon, accounts for this similarity in composition while also yielding an appropriate mass for Earth ...

It's a big claim, but Washington University in St. Louis planetary scientist Frédéric Moynier says his group has discovered evidence that the Moon was born in a flaming blaze of glory when a body the size of Mars collided with the early Earth. The evidence might not seem all that impressive to a nonscientist: a tiny excess of a heavier variant of the element zinc in Moon rocks. But the enrichment probably arose because heavier zinc atoms condensed out of the roiling cloud of vaporized rock created by a catastrophic collision faster than lighter zinc atoms, and the remaining ...

SANTA CRUZ, CA--Among the oddities of the outer solar system are the middle-sized moons of Saturn, a half-dozen icy bodies dwarfed by Saturn's massive moon Titan. According to a new model for the origin of the Saturn system, these middle-sized moons were spawned during giant impacts in which several major satellites merged to form Titan. Erik Asphaug, professor of Earth and planetary sciences at the University of California, Santa Cruz, will present this new hypothesis October 19 at the annual meeting of the Division for Planetary Sciences of the American Astronomical ...

It takes both teeth and jaws to make a pretty smile, but the evolutionary origins of these parts of our anatomy have only just been discovered, thanks to a particle accelerator and a long dead fish. All living jawed vertebrates (animals with backbones, such as humans) have teeth, but it has long been thought that the first jawed vertebrates lacked pearly gnashers, instead capturing prey with gruesome scissor-like jaw-bones. However new research, led by the University of Bristol and published today in Nature, shows that these earliest jawed vertebrates possessed teeth ...

DURHAM, N.C. – Researchers at the Duke-NUS Graduate Medical School in Singapore have identified numerous new subtypes of gastric cancer that are triggered by environmental factors. Reported in the Oct. 17, 2012, issue of the journal Science Translational Medicine, the findings are based on the science of epigenetics, a study of gene activity. The insights into the complexities of stomach cancer could lead to better treatment approaches for the second leading cancer killer in the world, behind lung cancer. "Gastric cancer is a heterogenous disease with individual patients ...

An Indiana University study that examined the effect of age and physical activity on lower leg muscle reflexes and coordination concluded that participation in physical activity was beneficial for lower leg muscle coordination across both sides of the body in both young and older study participants. Lower limb muscle communication is essential for everyday tasks, such as walking, balancing, and climbing stairs. "The results of this study suggest that participation in physical activity contributes to greater crossed-spinal reflex stability in both young and elderly subjects," ...

A mayfly trapped in 16-million-year-old-amber reveals a hitchhiking springtail, a wingless arthropod that is amongst the most commonly found bugs all over the world. The new research, published Oct 17 in the open access journal PLOS ONE led by David Penney from the University of Manchester, UK, is the first to show that springtails travelled on winged insects like mayflies, and only the second example of this mode of travel by springtails in the past or present. Springtails are among the most abundant group of arthropods, found in large numbers in soil all over the world. ...

Dolphins sleep with only one half of their brains at a time, and according to new research published Oct. 17 in the open access journal PLOS ONE, this trait allows them to stay constantly alert for at least 15 days in a row. Brian Branstetter from the National Marine Mammal Foundation and colleagues found that dolphins can use echolocation with near-perfect accuracy continuously for up to 15 days, identifying targets and monitoring their environment. The researchers studied 2 dolphins, one male and one female, and found that they were capable of this task with no signs ...

Men and women with autism spectrum conditions (ASC) may show subtle but significant differences in the cognitive functions impacted by the condition, according to new research published Oct 17 by Meng-Chuan Lai and colleagues from the Autism Research Centre at the University of Cambridge, UK in the open access journal PLOS ONE. Though individuals with autism show sex-specific differences in serum biomarkers, genetics and brain anatomy, little is known about any sex-dependent differences in cognition caused by ASC. Following their previous report on behavioral sex differences ...

Children with autism have difficulty identifying inappropriate social behavior, and even when successful, they are often unable to justify why the behavior seemed inappropriate. New brain imaging studies show that children with autism may recognize socially inappropriate behavior, but have difficulty using spoken language to explain why the behavior is considered inappropriate, according to research published Oct. 17 in the open access journal PLOS ONE by Elizabeth Carter from Carnegie Mellon University and colleagues. The authors say the results of their functional ...

Crows fed on prion-infected brains from mice can transmit these infectious agents in their feces and may play a role in the geographic spread of diseases caused by prions, such as chronic wasting disease or scrapie. The new research published Oct. 17 in the open access journal PLOS ONE by Kurt VerCauteren from the US Department of Agriculture (USDA) and other colleagues, shows that prions can pass through crows' digestive systems without being destroyed, and may be excreted intact after ingestion by the birds. According to the authors, their results demonstrate a potential ...

European astronomers have discovered a planet with about the mass of the Earth orbiting a star in the Alpha Centauri system — the nearest to Earth. It is also the lightest exoplanet ever discovered around a star like the Sun. The planet was detected using the HARPS instrument on the 3.6-metre telescope at ESO's La Silla Observatory in Chile. The results will appear online in the journal Nature on 17 October 2012. Alpha Centauri is one of the brightest stars in the southern skies and is the nearest stellar system to our Solar System -- only 4.3 light-years away. It is ...

Women whose first pregnancy is ectopic are likely to have fewer children in the following 20-30 years than women whose first pregnancy ends in a delivery, miscarriage or abortion, according to results from a study of nearly 3,000 women in Denmark. In addition, these women have a five-fold increased risk of a subsequent ectopic pregnancy. The first study to look at long-term reproductive outcomes in women whose first pregnancy was ectopic is published online today (Thursday) in Europe's leading reproductive medicine journal Human Reproduction [1]. Ectopic pregnancies ...

PHILADELPHIA - Changes in the ability to smell and taste can be caused by a simple cold or upper respiratory tract infection, but they may also be among the first signs of neurodegenerative disorders such as Alzheimer's disease and Parkinson's disease. Now, new research from the Perelman School of Medicine at the University of Pennsylvania has revealed an association between an impaired sense of smell and myasthenia gravis (MG), a chronic autoimmune neuromuscular disease characterized by fluctuating fatigue and muscle weakness. The findings are published in the latest edition ...

Men have borne the brunt of worsening mental health across the population of England since the start of the economic downturn in 2008, reveals research published in the online journal BMJ Open. But unemployment and a falling household income don't seem to be the culprits, prompting the authors to suggest that it is the threat of losing their jobs that has affected men's mental health. They base their findings on data taken from the national representative annual Health Survey for England for adults aged 25 to 64, between 1991 and 2010. Response rates during this ...

Bariatric surgery—restrictive gastric banding and other types of gastric bypass—can radically reduce risk factors for heart disease and stroke, and within a short period of time, indicates an analysis of the available evidence, published online in Heart. The impact is much greater and faster than drug treatments for weight management or diabetes, say the authors, and in some cases, could be life-saving. Being obese or overweight kills more than 2.6 million people every year. And the evidence shows that excess body fat produces harmful chemicals and skews gut hormones ...

BATON ROUGE – LSU's John Fleeger, professor emeritus in LSU's Department of Biological Sciences, is part of a multi-disciplinary national research group that recently discovered the impact of nutrient enrichment on salt marsh ecosystems is marsh loss and that such loss is seen much faster than previously thought. Globally between a quarter and half of the area of the world's tidal marshes has already been lost, and although multiple factors – sea-level rise, development, loss of sediment supply – are known to contribute to marsh loss, in some locations the causes have remained ...

Fresh examinations of lunar rocks gathered by Apollo mission astronauts have yielded new insights about the moon's chemical makeup as well as clues about the giant impacts that may have shaped the early beginnings of Earth and the moon. Geochemist James Day of Scripps Institution of Oceanography at UC San Diego and colleagues Randal Paniello and Frédéric Moynier at Washington University in St. Louis used advanced technological instrumentation to probe the chemical signatures of moon rocks obtained during four lunar missions and meteorites collected from the Antarctic. ...

An international consortium of scientists has published a high resolution draft of the barley genome. The research, published in the journal Nature, will help to produce new and better barley varieties that are vital for the beer and whisky industries. The UK team behind the research was led by Professor Robbie Waugh of Scotland's James Hutton Institute who worked with researchers at The Genome Analysis Centre, Norwich. Barley is the second most important crop in UK agriculture and malting barley underpins brewing and pub industries worth some £20 billion to the UK ...

As the climate changes, conservationists are divided over the most effective way to preserve animal and plant diversity because they cannot simply preserve the status quo. Ensuring species can shift to track the climate to which they are suited is a complex problem, especially when there are competing demands on land use. A simple prediction is that more habitat would help species to shift, but it is not obvious what the best spatial locations for habitat would be. A new study led by scientists at the University of York says that well placed habitat "stepping stones" would ...

Stunning images, including video footage, from a CT scan of amber have revealed the first evidence of any creature using an adult mayfly for transport. Researchers at the University of Manchester say this 16 million-year-old hitchhiker most likely demonstrates activity that is taking place today but has never previously been recorded. Entombed in amber the tiny springtail can be seen resting in a v-shaped depression at the base of one of the mayfly's wings. It appears to have secured itself for transport using its prehensile antennae. Dr David Penney and colleagues ...

New Rochelle, NY, October 17, 2012—Among adults who use social media such as Facebook, YouTube, Twitter, and blogs for political purposes, 42% are under the age of 30. A case study of the controversial Budget Repair Bill in Wisconsin explored whether young adults who use social media are more likely to engage in offline protests, and the results are published in an article in Cyberpsychology, Behavior, and Social Networking, a peer-reviewed journal from Mary Ann Liebert, Inc., publishers. The article is available free online on the Cyberpsychology, Behavior, and Social ...

A potential new treatment for traumatic brain injury (TBI), which affects thousands of soldiers, auto accident victims, athletes and others each year, has shown promise in laboratory research, scientists are reporting. TBI can occur in individuals who experience a violent blow to the head that makes the brain collide with the inside of the skull, a gunshot injury or exposure to a nearby explosion. The report on TBI, which currently cannot be treated and may result in permanent brain damage or death, appears in the journal ACS Nano. Thomas Kent, James Tour and colleagues ...

Scientists are reporting development of a new malaria drug that, in laboratory tests, has been twice as effective as the best current medicine against this global scourge and may fight off the disease with one dose, instead of the multiple doses that people often fail to take. A report on the drug appears in ACS' Journal of Medicinal Chemistry. Gary Posner and colleagues explain that malaria continues to kill almost 1 million people annually. The best existing treatment is so-called artemisinin combination therapy (ACT). It requires patients to take pills every day for ...

Leaves of the plant that yields carob — the substitute for chocolate that some consider healthier than chocolate — are a rich source of antibacterial substances ideal for fighting the microbe responsible for listeriosis, a serious form of food poisoning, according to a report in ACS' Journal of Agricultural and Food Chemistry. Nadhem Aissani and colleagues explain that the increase in antibiotic-resistant bacteria has fostered a search for new natural substances to preserve food and control disease-causing microbes. They cite a need for new substances to combat Listeria ...