Image of the Week: Simulations Reveal Unusual Death for Stars
Massive primordial stars, between 55,000 and 56,000 times the mass of our Sun, may have died unusually. In death, these objects — among the universe’s first generation of stars — would have exploded as supernovae and burned completely, leaving no remnant black hole behind.
Astrophysicists at the UC Santa Cruz and the Univ. of Minnesota came to this conclusion after running a number of supercomputer simulations at the Department of Energy’s (DOE) National Energy Research Scientific Computing Center (NERSC) and Minnesota Supercomputing Institute. They relied extensively on CASTRO, a compressible astrophysics code developed at the DOE’s Lawrence Berkeley National Laboratory’s (Berkeley Lab’s) Computational Research Division (CRD). Their findings were recently published in the Astrophysical Journal (ApJ).
Listeria are extremely undemanding bacteria. In low amounts they are present almost everywhere, including soil and water. In order to better understand how Listeria spread, a group of scientists from the Institute of Milk Hygiene at the Univ. of Veterinary Medicine, Vienna collected soil and water samples throughout Austria. Their study revealed a higher detection of Listeria in soil and water samples during periods of flooding. The researchers also found antibiotic-resistant strains of Listeria in soil samples. The data were published in the journal Applied Environmental Microbiology.
The literature describes Listeria as ubiquitous bacteria with widespread occurrence. Yet they only become a problem for humans and animals when they contaminate food processing facilities, multiply and enter the food chain in high concentrations. An infection with Listeria monocytogenes can even be fatal for humans or animals with weakened immune systems.
The key to creating a material that would be ideal for converting solar energy to heat is tuning the material’s spectrum of absorption just right. It should absorb virtually all wavelengths of light that reach Earth’s surface from the sun — but not much of the rest of the spectrum, since that would increase the energy that is reradiated by the material, and thus lost to the conversion process.
Now, researchers at MIT say they have accomplished the development of a material that comes very close to the “ideal” for solar absorption. The material is a two-dimensional metallic dielectric photonic crystal, and has the additional benefits of absorbing sunlight from a wide range of angles and withstanding extremely high temperatures. Perhaps most importantly, the material can also be made cheaply at large scales.
Dolphins are sensitive to magnetic stimuli and they behave differently when swimming near magnetized objects, according to Dorothee Kremers and her colleagues at Ethos unit of the Université de Rennes. They work appears in Springer’s journal Naturwissenschaften – The Science of Nature. Their research, conducted in the delphinarium of Planète Sauvage in France, provides experimental behavioral proof that these marine animals are magnetoreceptive.
Magnetoreception implies the ability to perceive a magnetic field. It is supposed to play an important role in how some land and aquatic species orientate and navigate themselves. Some observations of the migration routes of free-ranging cetaceans, such as whales, dolphins and porpoises, and their stranding sites suggested that they may also be sensitive to geomagnetic fields.
Droplets are simple spheres of fluid, not normally considered capable of doing anything on their own. But now, researchers have made droplets of alcohol move through water. In the future, such moving droplets may deliver medicines.
To be able to move on your own – to be self-moving – is a feature normally seen in living organisms. But also non-living entities can be self-moving, report researchers from Univ. of Southern Denmark and Institute of Chemical Technology in Prague, Czech Republic.
The number of days an expectant mother was deprived of electricity during Quebec’s 1998 Ice Storm predicts the epigenetic profile of her child, a new study found.
Scientists from the Douglas Mental Health Univ. Institute and McGill Univ. have detected a distinctive “signature” in the DNA of children born in the aftermath of the massive Quebec ice storm. Five months after the event, researchers recruited women who had been pregnant during the disaster and assessed their degrees of hardship and distress in a study called Project Ice Storm.
Brisbane researchers have developed a blood test that can accurately detect one of the commonest causes of hay fever, paving the way for new treatments.
The research, by The Univ. of Queensland and Sullivan Nicolaides Pathology, promises relief to the sufferers who endure the annual misery of sneezing, runny noses and itchy eyes when the pollen count climbs.
The nation’s largest tobacco companies are challenging court-ordered advertisements requiring the cigarette makers to say they lied about the dangers of smoking.
The so-called corrective statements are part of a case the government brought in 1999 under the Racketeer Influenced and Corrupt Organizations Act. U.S. District Judge Gladys Kessler ruled in 2006 that the nation’s largest cigarette makers concealed the dangers of smoking for decades and has since ordered them to pay for the statements in various advertisements in newspapers, as well as on TV, websites and cigarette pack inserts.
Young Women Don’t Recognize Cervical Cancer Symptoms
New research led by King’s College London suggests that many women under 30 with cervical cancer are diagnosed more than three months after first having symptoms. In many cases, this was because they did not recognize the symptoms as serious. The study is published today in the British Journal of General Practice.
Approximately one in 134 women will get cervical cancer at some point in their lives. It is most common in women in their thirties. Cervical cancer is nearly always caused by the Human Papillomavirus (HPV). HPV infection is very common, especially in young women, but for most, the infection resolves completely on its own and does not lead to cervical cancer. In England, the NHS offers screening to prevent cervical cancer to women aged 25-64.
Genome from Southern Africa Sheds Light on Human Origins
What can DNA from the skeleton of a man who lived 2,330 years ago in the southernmost tip of Africa tell us about ourselves as humans? A great deal when his DNA profile is one of the earliest diverged – oldest in genetic terms – found to-date in a region where modern humans are believed to have originated roughly 200,000 years ago.
The man’s mitochondrial DNA was sequenced to provide clues to early modern human prehistory and evolution. Mitochondrial DNA provided the first evidence that we all come from Africa, and helps us map a figurative genetic tree, all branches deriving from a common “Mitochondrial Eve.”
Teen girls who have sex should use IUDs or hormonal implants — long-acting birth control methods that are effective, safe and easy to use, the nation’s most influential pediatricians’ group recommends.
In an updated policy, the American Academy of Pediatrics says condoms also should be used every time teens have sex, to provide protection against sexually transmitted diseases that other forms of birth control don’t provide, and to boost chances of preventing pregnancy.
Greenland More Vulnerable to Climate Change than Thought
A new model developed by researchers at the Univ. of Cambridge has shown that despite its apparent stability, the massive ice sheet covering most of Greenland is more sensitive to climate change than earlier estimates have suggested, which would accelerate the rising sea levels that threaten coastal communities worldwide.
In addition to assessing the impact of the increasing levels of melt water created and spilled into the ocean each year as the climate continues to warm, the new model also takes into account the role that the soft, spongy ground beneath the ice sheet plays in its changing dynamics.
Using ecstasy significantly affects a person’s ability to detect faces, shapes and patterns, research has found.
The study, published in the Journal of Psychopharmacology, discovered ecstasy users were poorer than matched controls at detecting patterns through global form processing, a mechanism that helps the brain to detect visual information.
Years before they show any other signs of disease, pancreatic cancer patients have very high levels of certain amino acids in their bloodstream, according to a new study from MIT, Dana-Farber Cancer Institute and the Broad Institute.
This find, which suggests that muscle tissue is broken down in the disease’s earliest stages, could offer new insights into developing early diagnostics for pancreatic cancer, which kills about 40,000 Americans every year and is usually not caught until it is too late to treat.
Scientists looking at 16 cases of wild weather around the world last year see the fingerprints of man-made global warming on more than half of them.
Researchers found that climate change increased the odds of nine extremes: heat waves in Australia, Europe, China, Japan and Korea, intense rain in parts of the U.S. and India and severe droughts in California and New Zealand. The California drought, though, comes with an asterisk.