Parthenogenesis is a form of asexual reproduction during which unfertilized eggs begin to develop as if they had been fertilized. It occurs naturally in many plants and a few invertebrate (some bees, scorpions, parasitic wasps) and vertebrate animals (some fish, reptiles, and amphibians), but does not occur naturally in mammals. In 2007, researchers were able to chemically induce human egg cells to undergo parthenogenesis. The resulting parthenogenote has properties similar to an embryo, but cannot develop further. In this issue of the Journal of Clinical Investigation, ...

Washington, DC (February 19, 2013) – Parents know that one day they will have to talk to their children about drug use. The hardest part is to decide whether or not talking about ones own drug use will be useful in communicating an antidrug message. Recent research, published in the journal Human Communication Research, found that children whose parents did not disclose drug use, but delivered a strong antidrug message, were more likely to exhibit antidrug attitudes. Jennifer A. Kam, University of Illinois at Urbana-Champaign and Ashley V. Middleton, MSO Health Information ...

Los Angeles, CA (February 22, 2013) Studies report that since 2004, suicides rates in the U.S. Army have been on the rise. While researchers debate the cause, a new study finds that among suicide cases from 2007 – 2010, young white males were more at risk than any other demographic. This study, out today, will be published in Armed Forces & Society, a SAGE journal published on behalf of the Inter-University Seminar on Armed Forces and Society. Army Research Psychologists James Griffith and Mark Vaitkus analyzed data from the Army National Guard's (ARNG) personnel data ...

National Science Foundation- (NSF) funded researchers at Amherst College in Massachusetts and the University of Texas at Austin have described a new technique based in particle physics that might one day reveal, in more detail than ever before, the composition and characteristics of the deep Earth. There's just one catch: the technique relies on a fifth force of nature that has not yet been detected, but some particle physicists think it might exist. The fifth force would be in addition to gravity, the weak and strong nuclear forces and electromagnetism. Physicists ...

The study combines the cycles of sulphur, nitrogen and carbon in the ecosystem, as it shows that the molecular clusters need sulphuric acid, amines and oxygenated organics for growth. When the clusters reach a size of 1.5-2 nm, their growth increases considerably. The measurements were conducted at the University of Helsinki SMEAR II (Station for Measuring Forest Ecosystem-Atmosphere Relations) measurement station in Hyytiälä, southern Finland, which is among the most comprehensive stations in the world for atmosphere and biosphere research. During the last five years, ...

When fruit flies sense parasitic wasps in their environment, they lay their eggs in an alcohol-soaked environment, essentially forcing their larvae to consume booze as a drug to combat the deadly wasps. The discovery by biologists at Emory University is being published in the journal Science on Friday, February 22. "The adult flies actually anticipate an infection risk to their children, and then they medicate them by depositing them in alcohol," says Todd Schlenke, the Emory evolutionary geneticist whose lab led the research. "We found that this medicating behavior ...

This press release is available in German. Silicon nanocrystals have a size of a few nanometers and possess a high luminous potential. Scientists of KIT and the University of Toronto/Canada have now succeeded in manufacturing silicon-based light-emitting diodes (SiLEDs). They are free of heavy metals and can emit light in various colors. The team of chemists, materials researchers, nanoscientists, and opto-electronic experts presents its development in the "Nano Letters" journal (DOI: 10.1021/nl3038689). Silicon dominates in microelectronics and photovoltaics ...

Our ancestors evolutionarily split from those of rhesus monkeys about 25 million years ago. Since then, brain areas have been added, have disappeared or have changed in function. This raises the question, 'Has evolution given humans unique brain structures?'. Scientists have entertained the idea before but conclusive evidence was lacking. By combining different research methods, we now have a first piece of evidence that could prove that humans have unique cortical brain networks. Professor Vanduffel explains: "We did functional brain scans in humans and rhesus monkeys ...

Researchers at Umeå University in Sweden conclude that public opposition to dam removal is not based on knowledge deficiency, as is sometimes argued in dam removal science. It is instead a case of different understandings and valuation of the environment and the functions it provides. The findings are now published in the journal Ecology and Society. Dam removal is an increasingly common practice as old splash dams and small hydropower dams have become obsolete. Although the removal of these dams has ecological benefits by restoring rivers to their former courses, local ...

PITTSBURGH—At a time when the U.S. government is contemplating changes to federal guidelines governing research with humans, serious questions are being raised about the role of Institutional Review Boards (IRBs) in overseeing such research. Particularly, vocal critics have cited lost time, money and even lives under a system that they claim consumes scarce resources and stifles academic freedom. In response, defenders of the IRB system point to the need to protect research participants from abuse. Carnegie Mellon University's Alex John London, an internationally renowned ...

Despite years of research, the genetic factors behind many human diseases and characteristics remain unknown. The inability to find the complete genetic causes of family traits such as height or the risk of type 2 diabetes has been called the "missing heritability" problem. A new study by Princeton University researchers, however, suggests that missing heritability may not be missing after all — at least not in yeast cells, which the researchers used as a model for studying the problem. Published in the journal Nature, the results suggest that heritability in humans ...

State supreme court justices who don't face voters are generally more effective than their elected counterparts, according to research led by Princeton University political scientists. The research combines data about almost 6,000 state supreme court rulings nationwide between 1995 and 1998 with a new theoretical model to reach the conclusions that appointed justices generally bring a higher quality of information to the decision-making process, are more likely to change their preconceived opinions about a case, and are less likely to make errors than elected justices. "Judges ...

WASHINGTON, DC – With only one week left before sequestration is to take effect, America's research community sustained its call for an end to the across-the-board cuts to discretionary spending that will severely restrict the nation's ability to invest in the basic scientific research that drives innovation and produces economic growth. Sequestration will reduce federal funding for scientific research by nearly $95 billion over the next nine years, which will result in a reduction of U.S. GDP by at least $203 billion. The net impact will be 200,000 fewer jobs per year ...

BEER-SHEVA, Israel, February 21, 2013 -- Rocket attacks in Sderot, Israel significantly increase the likelihood of miscarriages, according to a new study by Ben-Gurion University of the Negev (BGU) researchers. The study, published in the January issue of Psychosomatic Medicine Journal of Bio-behavioral Medicine, compared 1,341 pregnancies of women (exposed group) who resided in Sderot, an area exposed to frequent rocket fire, with 2,143 pregnancies of women who lived in Kiryat Gat (unexposed group), which is out of range of missiles. Among women residing in the exposed ...

A new climate model predicts an increase in snowfall for the Earth's polar regions and highest altitudes, but an overall drop in snowfall for the globe, as carbon dioxide levels rise over the next century. The decline in snowfall could spell trouble for regions such as the western United States that rely on snowmelt as a source of fresh water. The projections are the result of a new climate model developed at the National Oceanic and Atmospheric Administration (NOAA) Geophysical Fluid Dynamics Laboratory (GFDL) and analyzed by scientists at GFDL and Princeton University. ...

This press release is available in Spanish. Studies at the U.S. Department of Agriculture (USDA) are shedding some light on the microbes that dwell in cattle manure—what they are, where they thrive, where they struggle, and where they can end up. This research, which is being conducted by Agricultural Research Service (ARS) scientists at the agency's Agroecosystems Management Research Unit in Lincoln, Neb., supports the USDA priority of ensuring food safety. ARS is USDA's chief intramural scientific research agency. In one project, ARS microbiologist Lisa Durso ...

Highlights Dialysis patients using catheters to access the blood have the highest risks for death, infections, and cardiovascular events compared with patients using other types of vascular access. Higher quality studies are needed to determine the true safety of different types of vascular access used for hemodialysis. Worldwide, more than 1.5 million people are treated with hemodialysis. Washington, DC (February 21, 2013) — Dialysis patients using catheters to access the blood have the highest risks for death, infections, and cardiovascular events compared with ...

Highlights Certain mutations and combinations of mutations in immune-related genes affect individuals' risk of developing a rare but serious kidney condition. These mutations also affect patient prognosis following different treatments.About half of patients with the condition, called atypical hemolytic uremic syndrome, develop kidney failure. Washington, DC (February 21, 2013) — Certain gene mutations affect individuals' risk of developing a serious kidney condition, as well as their prognosis after being diagnosed with the disease, according to a study appearing in ...

VIDEO: Penn's Dennis Discher explains how his lab designed a protein that acts a "passport " for the body's immune system. Nanoparticles equipped with this passport last longer in the bloodstream than... Click here for more information. PHILADELPHIA — The body's immune system exists to identify and destroy foreign objects, whether they are bacteria, viruses, flecks of dirt or splinters. Unfortunately, nanoparticles designed to deliver drugs, and implanted devices ...

In the first human study of its kind, researchers activated heart failure patients' stem cells with gene therapy to improve their symptoms, heart function and quality of life, according to a study in the American Heart Association journal Circulation Research. Researchers delivered a gene that encodes a factor called SDF-1 to activate stem cells like a "homing" signal. The study is unique because researchers introduced the "homing" factor to draw stem cells to the site of injury and enhance the body's stem cell-based repair process. Generally, researchers extract and ...

Flowers' methods of communicating are at least as sophisticated as any devised by an advertising agency, according to a new study, published today in Science Express by researchers from the University of Bristol. The research shows for the first time that pollinators such as bumblebees are able to find and distinguish electric signals given out by flowers. However, for any advert to be successful, it has to reach, and be perceived by, its target audience. Flowers often produce bright colours, patterns and enticing fragrance to attract their pollinators. Researchers ...

GAINESVILLE, Fla. --- Malaria does not have to be eradicated globally for individual countries to succeed at maintaining elimination of the disease, according to research from the University of Florida's Emerging Pathogens Institute and department of geography, to be published in the journal Science Feb. 22. Researchers Andrew Tatem and Christina Chiyaka found that those countries that have eliminated malaria have maintained their malaria-free states with remarkable stability, going against traditional theory. Between 1945 and 2010, 79 countries eliminated malaria and ...

Researchers from Amherst College and The University of Texas at Austin have described a new technique that might one day reveal in higher detail than ever before the composition and characteristics of the deep Earth. There's just one catch: The technique relies on a fifth force of nature (in addition to gravity, the weak and strong nuclear forces and electromagnetism) that has not yet been detected, but which some particle physicists think might exist. Physicists call this type of force a long-range spin-spin interaction. If it does exist, this exotic new force would ...

A new class of influenza drug has been shown effective against drug-resistant strains of the flu virus, according to a study led by University of British Columbia researchers. Published online today in the journal Science Express, the study details the development of a new drug candidate that prevents the flu virus from spreading from one cell to the next. The drug is shown to successfully treat mice with lethal strains of the flu virus. In order to spread in the body, the flu virus first uses a protein, called hemagglutinin, to bind to the healthy cell's receptors. ...

Researchers have successfully applied a novel method of vaccine creation for Chikungunya virus (CHIKV) using a technique called large scale random codon re-encoding. Using this approach, a group from the UMR_D 190, Emerging viruses Department in Marseille, France in collaboration with the University of Sydney, Australia, demonstrated that the engineered viruses exhibit a stable phenotype with a significantly decreased viral fitness (i.e., replication capacity), making it a new vaccine candidate for this emerging viral disease. This new report publishes on February 21 in ...