Παρασκευή 21 Φεβρουαρίου 2014

ScienceDaily: Top Science News

ScienceDaily: Top Science News


Food packaging chemicals may be harmful to human health over long term

Posted: 19 Feb 2014 05:52 PM PST

The synthetic chemicals used in the packaging, storage, and processing of foodstuffs might be harmful to human health over the long term, warn environmental scientists. This is because most of these substances are not inert and can leach into the foods we eat, they say. Despite the fact that some of these chemicals are regulated, people who eat packaged or processed foods are likely to be chronically exposed to low levels of these substances throughout their lives. And far too little is known about their long term impact.

Nothing so sweet as a voice like your own, study finds

Posted: 19 Feb 2014 02:48 PM PST

Have you ever noticed that your best friends speak the same way? A new study finds we prefer voices that are similar to our own because they convey a soothing sense of community and social belongingness.

Whole genome analysis speeds up: 240 full genomes in 50 hours

Posted: 19 Feb 2014 02:31 PM PST

Although the time and cost of sequencing the human genome has plummeted, analyzing the 3 billion base pairs of genetic information can take months. Researchers working with Beagle —- one of the world's fastest supercomputers devoted to life sciences —- report they can analyze 240 full genomes in 50 hours.

The musical brain: Novel study of jazz players shows common brain circuitry processes both music, language

Posted: 19 Feb 2014 02:31 PM PST

The brains of jazz musicians engrossed in spontaneous, improvisational musical conversation showed robust activation of brain areas traditionally associated with spoken language and syntax, which are used to interpret the structure of phrases and sentences. But this musical conversation shut down brain areas linked to semantics -- those that process the meaning of spoken language, according to results of a novel study.

Seal evolution: Sexual dimorphism in pinnipeds arose around 27 million years ago as climate changed

Posted: 19 Feb 2014 01:04 PM PST

Modern pinnipeds (the group that includes seals, sea lions and walruses) show a range of sexual dimorphism (large differences in size between males and females) and mating systems that span the extremes of modern mammals. A new study using the fossil record establishes that sexual dimorphism in pinnipeds, marked by harem-like behavior, arose around 27 million years ago in association with changing climatic conditions. Taken in the modern context of climate change, this research has major implications for the future of the species.

Brain signals move paralyzed limbs in new experiment

Posted: 19 Feb 2014 11:32 AM PST

To help people suffering paralysis from injury, stroke or disease, scientists have invented brain-machine interfaces that record electrical signals of neurons in the brain and translate them to movement. Usually, that means the neural signals direct a device, like a robotic arm. Researchers are now bringing brain-machine interfaces to the next level: Instead of signals directing a device, they hope to help paralyzed people move their own limb, just by thinking about it.

Using holograms to improve electronic devices

Posted: 19 Feb 2014 11:26 AM PST

Scientists have demonstrated a new type of holographic memory device that could provide unprecedented data storage capacity and data processing capabilities in electronic devices.

Cell therapy shows remarkable ability to eradicate cancer in clinical study

Posted: 19 Feb 2014 11:25 AM PST

The largest clinical study ever conducted to date of patients with advanced leukemia found that 88 percent achieved complete remissions after being treated with genetically modified versions of their own immune cells. "These extraordinary results demonstrate that cell therapy is a powerful treatment for patients who have exhausted all conventional therapies," said a senior author. "Our initial findings have held up in a larger cohort of patients, and we are already looking at new clinical studies to advance this novel therapeutic approach in fighting cancer."

Astronomers get first peek into core of supernova, using NuSTAR telescope

Posted: 19 Feb 2014 10:33 AM PST

Astronomers have peered for the first time into the heart of an exploding star in the final minutes of its existence. The feat by the high-energy X-ray satellite NuSTAR provides details of the physics of the core explosion inaccessible until now, says team member Steven Boggs of UC Berkeley. NuSTAR mapped radioactive titanium in the Cassiopeia A supernova remnant, which has expanded outward and become visible from Earth since the central star exploded in 1671.

The ups and downs of early atmospheric oxygen

Posted: 19 Feb 2014 10:33 AM PST

The period of extended low oxygen spanning from roughly two to less than one billion years ago was a time of remarkable chemical stability in the Earth's ocean and atmosphere. Biogeochemists report that oxygen was much lower than previously thought during this important middle chapter in Earth history, which likely explains the low abundances and diversity of eukaryotic organisms and the absence of animals.

Switch That Says It's Time to Sleep Identified

Posted: 19 Feb 2014 09:47 AM PST

The switch in the brain that sends us off to sleep has been identified in a study in fruit flies. The switch works by regulating the activity of a handful of sleep-promoting nerve cells, or neurons, in the brain. The neurons fire when we're tired and need sleep, and dampen down when we're fully rested. Although the research was carried out in fruit flies, or Drosophila, the scientists say the sleep mechanism is likely to be relevant to humans.

Dangers of ... sitting? Regardless of exercise, too much sedentary time is linked to major disability after 60

Posted: 19 Feb 2014 09:47 AM PST

If you're 60 and older, every additional hour a day you spend sitting is linked to doubling the risk of being disabled -- regardless of how much exercise you get, reports a new study. The study is the first to show sedentary behavior is its own risk factor for disability, separate from lack of moderate vigorous physical activity. In fact, sedentary behavior is almost as strong a risk factor for disability as lack of exercise.

Workings of working memory revealed

Posted: 19 Feb 2014 09:47 AM PST

Cognitive scientists have identified specific brain regions that work together to allow us to choose from among the options we store in working memory. Keep this in mind: Scientists say they've learned how your brain plucks information out of working memory when you decide to act. Say you're a busy mom trying to wrap up a work call now that you've arrived home. While you converse on your Bluetooth headset, one kid begs for an unspecified snack, another asks where his homework project has gone, and just then an urgent e-mail from your boss buzzes the phone in your purse. During the call's last few minutes these urgent requests -- snack, homework, boss -- wait in your working memory. When you hang up, you'll pick one and act.

Newly developed chemical restores light perception to blind mice

Posted: 19 Feb 2014 09:47 AM PST

Progressive degeneration of photoreceptors -- the rods and cones of the eyes -- causes blinding diseases such as retinitis pigmentosa and age-related macular degeneration. While there are currently no available treatments to reverse this degeneration, a newly developed compound allows other cells in the eye to act like photoreceptors. The compound may be a potential drug candidate for treating patients suffering from degenerative retinal disorders.

Clouds seen circling supermassive black hole

Posted: 19 Feb 2014 09:46 AM PST

Astronomers see huge clouds of gas orbiting supermassive black holes at the centres of galaxies. Once thought to be a relatively uniform, fog-like ring, the accreting matter instead forms clumps dense enough to intermittently dim the intense radiation blazing forth as these enormous objects condense and consume matter.

NASA satellites see Arctic surface darkening faster

Posted: 19 Feb 2014 08:51 AM PST

The retreat of sea ice in the Arctic Ocean is diminishing Earth's albedo, or reflectivity, by an amount considerably larger than previously estimated, according to a new study that uses data from instruments that fly aboard several NASA satellites.

Endangered black-footed ferret and its plague-impacted prey need new conservation approaches

Posted: 19 Feb 2014 07:22 AM PST

The black-footed ferret is one of the most endangered mammals in North America, but new research suggests that these charismatic critters can persist if conservationists think big enough.

Most of us have made best memories by age 25

Posted: 19 Feb 2014 06:53 AM PST

By the time most people are 25, they have made the most important memories of their lives, according to new research.

Dreams, déjà vu and delusions caused by faulty 'reality testing,' research shows

Posted: 19 Feb 2014 06:53 AM PST

New research has delved into the reasons why some people are unable to break free of their delusions, despite overwhelming evidence explaining the delusion isn't real.

How stick insects honed friction to grip without sticking

Posted: 19 Feb 2014 04:54 AM PST

When they're not hanging upside down, stick insects don't need to stick. In fact, when moving upright, sticking would be a hindrance: so much extra effort required to 'unstick' again with every step.

Gecko-inspired adhesion: Self-cleaning and reliable

Posted: 19 Feb 2014 04:52 AM PST

Geckos outclass adhesive tapes in one respect: Even after repeated contact with dirt and dust do their feet perfectly adhere to smooth surfaces. Researchers have now developed the first adhesive tape that does not only adhere to a surface as reliably as the toes of a gecko, but also possesses similar self-cleaning properties. Using such a tape, food packagings or bandages might be opened and closed several times.

Family problems experienced in childhood and adolescence affect brain development

Posted: 19 Feb 2014 04:52 AM PST

New research has revealed that exposure to common family problems during childhood and early adolescence affects brain development, which could lead to mental health issues in later life. The study used brain imaging technology to scan teenagers aged 17-19. It found that those who experienced mild to moderate family difficulties between birth and 11 years of age had developed a smaller cerebellum, an area of the brain associated with skill learning, stress regulation and sensory-motor control. The researchers also suggest that a smaller cerebellum may be a risk indicator of psychiatric disease later in life, as it is consistently found to be smaller in virtually all psychiatric illnesses.

Rife with hype, exoplanet study needs patience and refinement

Posted: 18 Feb 2014 12:38 PM PST

Despite many trumpeted results, few 'hard facts' about exoplanet atmospheres have actually been collected, and most of these data are of 'marginal utility,' according to a review of exoplanet research by an astrophysicist. The dominant methods for studying exoplanet atmospheres are not intended for planets trillions of miles from Earth. Instead, the future of exoplanet study should focus on the more difficult but comprehensive method of spectrometry.

Evolution stuck in slime for a billion years

Posted: 18 Feb 2014 11:33 AM PST

Researchers are providing a new explanation as to why life remained as little more than slime for a billion years, before rapidly diversifying in the 'Cambrian explosion of life'. Using a new technology originally developed for mineral exploration, the team has shown how varying levels of oxygen and biologically-important elements in the ancient oceans might have triggered the major evolutionary events that brought us here today.

When a black hole shreds a star, a bright flare tells the story

Posted: 18 Feb 2014 11:32 AM PST

A new study explains what happens during the disruption of a normal sun-like star by a supermassive black hole. The study shows why observers might fail to see evidence of the hydrogen in the star, casting doubt on a 2012 report of the disruption of an exotic helium star.

Hubble watches stars' clockwork motion in nearby galaxy

Posted: 18 Feb 2014 11:22 AM PST

Using the sharp-eyed NASA Hubble Space Telescope, astronomers have for the first time precisely measured the rotation rate of a galaxy based on the clock-like movement of its stars. According to their analysis, the central part of the neighboring galaxy, called the Large Magellanic Cloud (LMC), completes a rotation every 250 million years.

Stretchable, bendable electronics: A stretchable highway for light

Posted: 18 Feb 2014 08:07 AM PST

Electronics that bend and stretch have been demonstrated, but similar work in optics has lagged behind. Particularly difficult to engineer have been optics that stretch, lengthening when someone wearing body sensors bends to tie their shoe, or when a robotic arm twists through a full range of motion. Now scientists report the first optical circuit that uses interconnections that are not only bendable, but also stretchable.

Increase in Arctic cyclones is linked to climate change

Posted: 18 Feb 2014 07:07 AM PST

Winter in the Arctic is not only cold and dark; it is also storm season when hurricane-like cyclones traverse the northern waters from Iceland to Alaska. These cyclones are characterized by strong localized drops in sea level pressure, and as Arctic-wide decreases in sea level pressure are one of the expected results of climate change, this could increase extreme Arctic cyclone activity, including powerful storms in the spring and fall. A new study uses historical climate model simulations to demonstrate that there has been an Arctic-wide decrease in sea level pressure since the 1800's.

Δεν υπάρχουν σχόλια:

Δημοσίευση σχολίου