Sep 25, 2010

Building Language Skills More Critical for Boys Than Girls, Research Suggests

“Developing language skills appears to be more important for boys than girls in helping them to develop self-control and, ultimately, succeed in school, according to a study led by a Michigan State University researcher. Thus, more emphasis should be placed on encouraging boy toddlers to “use their words” — instead of unruly behavior — to solve problems, said Claire Vallotton, MSU assistant professor of child development. “It shouldn’t be chalked off as boys being boys,” Vallotton said. “They need extra attention from child-care providers and teachers to help them build language skills and to use those skills to regulate their emotions and behavior.”

The study, co-authored by Catherine Ayoub from Harvard Medical School, is the first to suggest language skills have a bigger impact on boys’ self-regulation than on girls’. The findings will appear in an upcoming issue of the journal Early Childhood Research Quarterly.
The researchers examined data on children as they aged from 1 to 3 and their mothers who participated in the National Early Head Start Research and Evaluation study. As with previous research, Vallotton and Ayoub found that language skills — specifically the building of vocabulary — help children regulate their emotions and behavior and that boys lag behind girls in both language skills and self-regulation.

What was surprising, Vallotton said, was that language skills seemed so much more important to the regulation of boys’ behavior. While girls overall seemed to have a more natural ability to control themselves and focus, boys with a strong vocabulary showed a dramatic increase in this ability to self-regulate — even doing as well in this regard as girls with a strong vocabulary.”
Read more at Science Daily

Sep 23, 2010

Why Does a Star Explode?

Nothing lights up the cosmos like a supernova. When a star dies in such a spectacular fashion, its demise releases colossal quantities of mass and energy, but why does a star explode to begin with?

Only a few varieties of stars end their lives this way and astronomers sort the explosions into two basic categories: type Ia supernovae and type II supernovae. While the exact self-destruction process varies with each type, all stellar explosions ultimately depend on the star's enormous mass.

When a Star Collapses
Type II supernovae are also known as core-collapse supernovae. These explosions only occur with stars at least eight times the size of our own (eight solar masses).

To understand exactly what takes place, you have to see a thriving star as a balance of inward and outward forces. The star's own mass exerts an inward pull of gravity, while the nuclear fusion reactions in its core apply an outward push of pressure. One force tries to expand the star; the other tries to crush it.

"Stars spend their life fusing various elements by nuclear reactions into heavier elements," says author and astrophysicist Mario Livio of the Space Telescope Science Institute. "For example, our own sun fuses hydrogen atoms into helium atoms, and that's the source of its energy."

Yet a star can only carry on this balancing act to a point. Eventually, the star's core turns to iron and without the outward push of fusion, the star collapses in on itself. Core temperature skyrockets under this intense pressure, breaking down the iron nuclei and causing the core itself to break down.

"The core collapses down to stupendous density," says Livio, "at which point there is something that is called a bounce. It's like when something hits a brick wall. The core collapses up to a point where it becomes extraordinarily hard to squeeze it anymore."

The bounce takes the form of a powerful shock wave, which blasts the entire steller envelope (several solar masses worth of material surrounding the core) away at a speed of 10,000 miles (16,093 kilometers) per second.

Read more at Discovery News

Einstein's theory of relativity works on a human scale: the higher you are, the faster you age

Researchers have demonstrated one of Einstein's theories of relativity - that the further away from the Earth you are, the faster time passes works even on a human scale.

That means – even though the differences are tiny – you really will age faster if you live on the top floor of a skyscraper than in a bungalow.

The discovery, made by scientists in the US, confirms a theory first proposed by Einstein – that clocks run faster the further away from the ground they are.

Although the concept has been accepted for many years, now the difference can be measured for the first time with astonishing accuracy.

Using a pair of the world's most precise clocks, physicists at the National Institute of Standards and Technology, Colorado, discovered that simply going upstairs will make you age faster.

If one of the clocks was moved just a foot higher, then it ran a little bit faster – albeit by a tiny fraction of a second.

So, taking just a couple of steps upwards will remove 90 billionths of a second to a 79-year lifetime.

By moving about 10 feet to the top of the stairs, you would age quicker by 900 billionths of a second.

And if you were to spend your life at the top of the 102-storey Empire State Building (1250 feet) you would lose 104 millionths of a second, said one of the researchers, James Chin-Wen Chou.

The experiments used "quantum logic" atomic clocks which can keep time to within one second over 3.7 billion years.

They prove the theory that clocks at higher elevations run faster because they are subject to less gravitational force.

Read more at The Telegraph

Sep 22, 2010

Budget cuts force CERN to shut accelerators for year

“Europe’s particle research center CERN unveiled budget cuts Friday that will force it to temporarily close its accelerators for a year in 2012, but said its flagship “Big Bang” machine will mainly be unaffected.

Announcing the trimmed-down budget, in which governments will provide 135 million Swiss francs ($133.4 million) less over a five-year period to 2015, CERN said its high-profile drive to study the origins of the cosmos would continue as planned.

It said it would delay upgrades to the Large Hadron Collider’s beam intensity by one year, achieving this in 2016 instead of 2015, meaning scientists will have to wait longer for experiments to gather data at a faster rate.

A particle accelerator is a machine that propels a beam of sub-atomic particles at high speed. Physicists use the machines to create high-energy collisions so they can study the properties of the fundamental building-blocks of matter.

CERN operates a network of accelerators, including the world’s biggest, the Large Hadron Collider (LHC), which opened two years ago to test predictions of high-energy physics.

CERN had previously announced that the LHC would not run in 2012 “for purely technical reasons.” It said it would now also shut down all of its other accelerators in 2012 as it focuses its resources on the most critical research.

“The whole CERN accelerator complex will now join the LHC in a year-long shutdown,” the institute said in a statement. “CERN management considers this a good result for the laboratory given the current financial environment.”

Scientists and technical staff staged a protest outside CERN’s main building on the French-Swiss border near Geneva last month over the possibility of budget cuts.”

Read more at Reuters

Speak, Memory: Language and the Brain

“In the field of neuroscience, we know far less about language than about other brain mechanisms like emotion, memory, or sensation. The inherent difficulty of studying language is that it is so closely linked to thought. There are certainly parts of the brain in which language is concentrated, but it is hard to differentiate these areas from those involved in non-language cognitive processes. Language areas also appear to be quite fluid, occupying different parts of the brain among different individuals. And because language is a strictly human phenomenon, researchers can’t use animal studies to investigate brains at the neuron level.

Paradoxically, language-specific areas were the first localized areas to be discovered in the brain. As discussed earlier in our Going Mental series, French physician Paul Broca and German neurologist Carl Wernicke independently discovered two important language areas in the 1860s. Based on their brain damage studies, a cohesive picture of language processing emerged: stimuli from the auditory cortex (speech) or the visual cortex (reading) travel to Wernicke’s area in the left posterior temporal lobe, where it is processed and comprehended. From there, a bundle of nerves called the arcuate fasiculus connects to Broca’s area in the frontal lobe, which is responsible for language production. From there, the message is sent to the motor cortex for translation either into speech or writing. This succinct language circuit was the prevailing model for over a century; the only problem is that new tests show it to be inaccurate.

“Neither nature nor the brain always fits into discrete boxes,” writes Dr. John Ratey, author of “A User’s Guide to the Brain.” “Recent MRI and PET studies and highly specific clinical tests of language abilities and impairments show that the ability to move the face and tongue in the sequence necessary to produce speech sounds like ‘da’ and ‘ta’ and the ability to hear and decode the same sounds are in Broca’s area of the brain. This indicates that speech production and comprehension are not independent systems,” he says. ”

Read more at Big Think

First Habitable Exoplanet Could Be Discovered by May

“A new mathematical analysis predicts the first truly habitable exoplanet will show itself by early May 2011.
Well, more or less. “There is some wiggle room,” said Samuel Arbesman of the Harvard Institute for Quantitative Social Science, lead author of a new paper posted online and to be published in PLoS ONE Oct. 4. His calculations predict a 50 percent probability that the first habitable exoplanet will be discovered in May 2011, a 66 percent chance by the end of 2013 and 75 percent chance by 2020.
“This is, as far as we can tell, right around the corner,” said exoplanet expert Greg Laughlin of the University of California, Santa Cruz, co-author of the paper.
Astronomers have found 490 planets outside our solar system to date, and those planets have been getting steadily smaller and more Earth-like. But none so far actually resemble Earth in its most important property: the ability to support life.
So Arbesman and Laughlin devised a mathematical way to define habitability using the techniques of scientometrics, the scientific study of science itself.”
Read more at Wired

Sep 20, 2010

Ancient Samaritan Synagogue Unearthed In Israel

Israeli archaeologists have uncovered the ruins of a 1,500-year-old synagogue near the city of Beit Shean in the Jordan Valley, the Israel Antiquities Authority announced on Monday.

The remains consist of a five- by eight-meter (16- by 26-foot) rectangular prayer hall whose walls featured five rectangular recesses built into them. Most likely, they housed wooden benches.

On the floor, the archaeologists found a colorful mosaic, decorated with a geometric pattern. In the center, a Greek inscription proclaimed: “This is the temple.”

According to Leah Di Segni, the scholar at the Hebrew University of Jerusalem who translated the inscription, the plan of the building, the orientation and the content of the inscription are in keeping with a Samaritan synagogue.

Indeed, the prayer hall faced southwest toward Mount Gerizim, a mound sacred to the Samaritans, people believed to have originated in the ancient northern kingdom of Israel.

Mentioned by Jesus in the parable of the Good Samaritan (Luke 10:25-37), the Samaritans, whose religion shares many similarities with Judaism, numbered around a million in the late Roman Empire.

Under the leadership of the high priest Baba Rabbah, they were granted national sovereignty. At the end of the reign of the Emperor Justinian in 529, however, following an unsuccessful revolt, they ceased to exist as a nation.

Today, the Samaritans are the smallest religio-ethnic group in existence.

Read more at Discovery News

Genocide Wiped Out Native American Population

Crushed leg bones, battered skulls and other mutilated human remains are likely all that's left of a Native American population destroyed by genocide that took place circa 800 A.D., suggests a new study.

The paper, accepted for publication in the Journal of Anthropological Archaeology, describes the single largest deposit to date of mutilated and processed human remains in the American Southwest.

The entire assemblage comprises 14,882 human skeletal fragments, as well as the mutilated remains of dogs and other animals killed at the massacre site -- Sacred Ridge, southwest of Durango, Colo.

Based on the archaeological findings, which include two-headed axes that tested positive for human blood, co-authors Jason Chuipka and James Potter believe the genocide occurred as a result of conflict between different Anasazi Ancestral Puebloan ethnic groups.

"It was entirely an inside job," Chuipka, an archaeologist with Woods Canyon Archaeological Consultants, told Discovery News.

"The type of event at Sacred Ridge is on the far end of the conflict spectrum where social relations completely melt down," he added, mentioning that the Sacred Ridge "occupants were targeted to take the blame."

Chuipka and Potter analyzed objects excavated at Sacred Ridge, which was a multiple habitation site of 22 pit structures, some of which may have operated as communal ritual facilities for a population that extended beyond the immediate site inhabitants. This suggests the residents at one point exerted some social control in the area.

The unearthed bones and artifacts indicate that when the violence took place, men, women and children were tortured, disemboweled, killed and often hacked to bits. In some cases, heads, hands and feet appear to have been removed as trophies for the killers. The attackers then removed belongings out of the structures and set the roofs on fire.

"I think that the major event was preceded by social stress within the community that may have been exacerbated by a period of drought," Chuipka said. "The scale of the mutilations suggests that it was planned and organized in the preceding days or weeks, and that the violence took place in a relatively short period of time -- a few days."

Read more at Discovery News

Sep 19, 2010

Blood test to predict diabetes 10 years earlier

The test can identify around half of people who will develop type 2 diabetes said researchers speaking at the British Science Festival in Birmingham.

It works by detecting levels of a genetic molecule in their blood, it was claimed.

The same molecule, called a microRNA (MiR), could help pinpoint sufferers at high risk of heart and artery disease.

Amongst the two million people in Britain who already have diabetes, the test can also distinguish between those who will and will not go on to develop some of the complications of diabetes caused by damage to blood vessels, such as heart attack, stroke and poor circulation.

The lead scientist Dr Manuel Mayr, from King's College London, said he expected the MiR test to be used in conjunction with conventional methods. It is likely to cost around £2.

Its biggest advantage was that it directly assessed the damage diabetes was causing to blood vessels.

"It's very important for doctors to define those diabetic patients that are at the highest risk of developing cardiovascular complications," said Dr Mayr.

"We hope that this new class of blood markers may give additional insight that we're currently not getting from other clinical tests."

Being able to identify which people with diabetes are particularly at risk of having a heart attack or stroke should allow doctors to begin early treatment with cholesterol and blood pressure lowering drugs and target it at those who are most likely to benefit.

Treating diabetes costs the NHS £9bn a year.

One type of micro-RNA, known as MiR-126, protects blood vessels from damage.

Healthy blood vessel cells are able to release substantial MiR-126 in to the blood stream.

However, when they become damaged, they need to keep the MiR-126 for themselves and shed less in to the blood.

Dr Mayr studied 822 adults aged between 40 and 79 living in northern Italy.

Of the two types of diabetes, type 2, or adult onset, diabetes is much more common.

Read more at The Telegraph