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How Slight Sleep Deprivation Could Add Extra Pounds
By Katherine Harmon
Getting seven to eight solid hours of sleep each night might seem an almost impossible luxury to many people. But not getting enough sleep is known to impair mental function and increase the risk for heart disease, among other ill effects. Accumulating evidence also suggests that even short-term, partial sleep deprivation could pave the way for weight gain and other negative metabolic consequences.
More than 28 percent of adults in the U.S. report that they get less than six hours of sleep a night, with this cumulative deprivation becoming more common in the past three decades. And now that more than 35 percent of U.S. adults are currently obese, researchers have been searching for potential links between the two conditions, in hopes of reducing the increasing health and economic burden of obesity. Establishing lack of sleep as a risk factor for weight gain could have important clinical and public health effects, possibly allowing people to make simple lifestyle changes to improve their metabolic health.
A new report, published online October 24 in the Journal of the Academy of Nutrition and Dietetics, reviews 18 carefully controlled laboratory studies that tested human subjects' physiological and behavioral responses to sleep deprivation as they relate to metabolic health.
Reena Mehra, an associate professor of medicine who studies sleep and health at Case Western Reserve University School of Medicine and who was not involved in the new analysis, notes that the new paper is "a well done review of the experimental data."
more
http://www.scientificamerican.com/article.cfm?id=sleep-deprivation-obesity
Easter Island Statues Might Have Been "Walked" Out of Quarry
By Ewen Callaway of Nature magazine
Easter Island’s gargantuan stone statues walked. That is the controversial claim from archaeologists who have demonstrated the feat with a 4.4-tonne model of one of the baffling busts. They describe their work in the Journal of Archaeological Science.
Nearly 1,000 statues litter Easter Island's 163 square kilometers, with the largest weighing 74 tons and standing 10 meters tall. Much about the megaliths is mystery, but few of the enigmas are more perplexing than how the statues were shuttled kilometers from the rock quarries where they were carved.
Archaeologists have proposed that the Polynesians who settled Easter Island 800 years ago or more laid the statues (called moai) prone and rolled them along on logs. That idea supports the theory that the settlers, known as Rapa Nui, became so obsessed with statue-building that they denuded the island of its forests. In his book Collapse (Viking, 2005), Jared Diamond, a geographer at the University of California, Los Angeles, touted Easter Island as the poster child for a civilization that blew through its natural resources and folded.
more with video
http://www.scientificamerican.com/article.cfm?id=easter-island-statues-might-have-been-walked-out-of-quarry
Too Big To Handle
WASHINGTON, DC – In the discussion of whether America’s largest financial institutions have become too big, a sea change in opinion is underway. Two years ago, during the debate about the Dodd-Frank financial-reform legislation, few people thought that global megabanks represented a pressing problem. Some prominent senators even suggested that very large European banks represented something of a role model for the United States.
In any case, the government, according to the largest banks’ CEOs, could not possibly impose a cap on their assets’ size, because to do so would undermine the productivity and competitiveness of the US economy. Such arguments are still heard – but, increasingly, only from those employed by global megabanks, including their lawyers, consultants, and docile economists.
Everyone else has shifted to the view that these financial behemoths have become too large and too complex to manage – with massive adverse consequences for the wider economy. And every time the CEO of such a bank is forced to resign, the evidence mounts that these organizations have become impossible to manage in a responsible way that generates sustainable value for shareholders and keeps taxpayers out of harm’s way.
Wilbur Ross, a legendary investor with great experience in the financial services sector, nicely articulated the informed private-sector view on this issue. He recently told CNBC,
more
http://www.project-syndicate.org/commentary/the-growing-consensus-against-big-banks-by-simon-johnson
The Laschamp Event- Rapid magnetic reversal only 41,000 years ago
About 41,000 years ago, a complete and rapid reversal of the geomagnetic field occurred. Magnetic studies of the GFZ German Research Centre for Geosciences on sediment cores from the Black Sea show that during this period, during the last ice age, a compass at the Black Sea would have pointed to the south instead of north. Moreover, data obtained by the research team formed around GFZ researchers Dr. Norbert Nowaczyk and Prof. Helge Arz, together with additional data from other studies in the North Atlantic, the South Pacific and Hawaii, prove that this polarity reversal was a global event. Their results are published in the latest issue of the scientific journal "Earth and Planetary Science Letters".
What is remarkable is the speed of the reversal: "The field geometry of reversed polarity, with field lines pointing into the opposite direction when compared to today's configuration, lasted for only about 440 years, and it was associated with a field strength that was only one quarter of today's field," explains Norbert Nowaczyk. "The actual polarity changes lasted only 250 years. In terms of geological time scales, that is very fast."
During this period, the field was even weaker, with only 5% of today's field strength. As a consequence, the Earth nearly completely lost its protection shield against hard cosmic rays, leading to a significantly increased radiation exposure.
This is documented by peaks of radioactive beryllium (10Be) in ice cores from this time, recovered from the Greenland ice sheet. 10Be as well as radioactive carbon (14C) is caused by the collision of high-energy protons from space with atoms of the atmosphere.
http://www.rdmag.com/news/2012/10/laschamp-event-earth’s-brief-geomagnetic-reversal-found
World’s most advanced mirror for giant telescope completed
Scientists at the University of Arizona and in California have completed the most challenging large astronomical mirror ever made.
For the past several years, a group of optical scientists and engineers working at the UA Steward Observatory Mirror Laboratory underneath the UA’s football stadium have been polishing an 8.4-m (27 ½ feet) diameter mirror with an unusual, highly asymmetric shape.
By the standards used by optical scientists, the “degree of difficulty” for this mirror is 10 times that of any previous large telescope mirror. The mirror surface matches the desired prescription to a precision of 19 nm—so smooth that if it were the size of the continental U.S., the highest mountains would be little more than a half-inch high.
This mirror, and six more like it, will form the heart of the 25-m Giant Magellan Telescope, providing more than 380 square meters, or 4,000 square feet, of light-collecting area. The Giant Magellan Telescope will lead a next generation of giant telescopes that will explore planets around other stars and the formation of stars, galaxies and black holes in the early universe.
Buell Jannuzi, director of the UA Steward Observatory and professor of astronomy, said, “Making this first GMT mirror required all the expertise and experience that the University has built up over 25 years of making telescope mirrors and a great deal of innovation to push beyond previous limits in optical fabrication and testing. In achieving this remarkable milestone, the team built and demonstrated all the equipment and techniques that will lead to efficient production of the remaining mirrors for the GMT.”
more
http://www.rdmag.com/news/2012/10/world’s-most-advanced-mirror-giant-telescope-completed
MIT Has Created The Most Slippery Surface By A Factor Of 10,000
MIT scientists have created a new kind of hydrophobic material that is incredibly slippery, beating existing hydrophobic surfaces by a factor of 10,000.
The key to the improved hydrophobic (water-shedding) surface is a combination of microscopic patterning—a surface covered with tiny bumps or posts just 10 um across, about the size of a red blood cell—and a coating of a lubricant, such as oil. The tiny spaces between the posts hold the oil in place through capillary action, the researchers found.
The team discovered that droplets of water condensing on this surface moved 10,000 times faster than on surfaces with just the hydrophobic patterning. The speed of this droplet motion is key to allowing the droplets to fall from the surface so that new ones can form, increasing the efficiency of heat transfer in a power plant condenser, or the rate of water production in a desalination plant.
With this new treatment, "drops can glide on the surface," Varanasi says, floating like pucks on an air-hockey table and looking like hovering UFOs—a behavior Varanasi says he has never seen in more than a decade of work on hydrophobic surfaces. "These are just crazy velocities."
more
http://www.technovelgy.com/ct/Science-Fiction-News.asp?NewsNum=3795
http://www.rdmag.com/news/2012/10/better-way-shed-water
Amazing Photo Captures 84 Million Stars in Our Milky Way Galaxy
Astronomers have catalogued 84 million stars at the heart of the Milky Way galaxy using an enormous cosmic photo snapped by a telescope in Chile, a view that is billed as the largest survey ever of the stars in our galaxy's core.
The staggering 9-gigapixel picture was created with data gathered by the Visible and Infrared Survey Telescope for Astronomy (VISTA), an instrument at the European Southern Observatory's Paranal Observatory in northern Chile. The zoomable image is so large that it would measure 30 feet long by 23 feet tall (9 by 7 meters) if printed with the resolution of a typical book, researchers said.
The catalogue derived from the new image contains 10 times more stars than previous studies have provided. It should help astronomers better understand the structure and evolution of our home galaxy, researchers said.
"By observing in detail the myriads of stars surrounding the center of the Milky Way we can learn a lot more about the formation and evolution of not only our galaxy, but also spiral galaxies in general," study lead author Roberto Saito, of the Pontificia Universidad Católica de Chile, Universidad de Valparaíso and The Milky Way Millennium Nucleus, said in a statement.
http://www.space.com/18193-milky-way-photo-84-millions-stars.html
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