How Hormone Puts a Kick in the Sperm's Tail
|10:56:18 AM, Thursday, March 17, 2011|
"It's exhausting being a sperm. Having made the long-distance swim up the fallopian tube, a sperm must then rev up its tail to propel itself through the thick jelly-like coating of the egg. The female hormone progesterone, released by the egg, prompts the tail to switch from a smooth swimming motion to a frantic flicking, but exactly how has been puzzling. Researchers have now shown that the hormone acts directly on a sperm surface protein, a discovery that may suggest new nonhormonal contraceptives.
For 10 years, researchers have suspected that progesterone, which the egg releases in huge quantities, is responsible for the asymmetrical, whiplike tail movements that give sperm enough torque to penetrate the ovum. Because sperm respond to progesterone within seconds, scientists reasoned that the hormone must bind to a surface protein and not one within the cells, which would take longer for the progesterone to reach.
In 2001, researchers hoped they had found the progesterone receptor when they discovered that infertile men and mice sometimes had mutations that disrupted a protein, called CatSper, which ferries calcium ions in and out of sperm. This so-called calcium channel is found exclusively within sperms' tails, but working out whether it responds to progesterone proved a thornier exercise than expected. Sperm are not easy cells to work with—for one thing, they don't stay still.
Now, two research teams have finally connected progesterone to CatSper by inserting a tiny electrode into individual sperm, a technique usually reserved for measuring the electrical signals in neurons. In independent studies appearing online in Nature today, the groups have documented the change in current inside a sperm as progesterone causes positively charged calcium ions to pass into the cell. And because a working ion channel produces a characteristic electrical fingerprint, the researchers were able to use their electrodes to demonstrate that CatSper was responsible for letting in the calcium..."
The Known Universe by American Museum of Natural History
|12:07:38 AM, Thursday, March 17, 2011|
-- And this is based on a data that is dated! In December of '10 ALONE a new estimation proved that there are at least three times more stars in the universe that previously thought....
Squirrel Attacking Residents of Vt. Neighborhood
|8:05:43 PM, Wednesday, March 16, 2011|
"BENNINGTON, Vt. – A Vermont neighborhood is being stalked by a renegade gray squirrel.
Several people in Bennington say they've been attacked by a squirrel over the last few weeks.
Kevin McDonald tells the Bennington Banner he was shoveling snow when the squirrel jumped onto him. He says he threw the animal off, but it twice jumped back onto him. A game warden says there have been other reports, too.
One woman is being treated for exposure to rabies, but Vermont Public Health Veterinarian Robert Johnson says there's never been a case of a squirrel passing rabies to a human.
Johnson says it's possible the squirrel was raised as a pet and lost its fear of humans. He says the squirrel might "go ballistic" when it encounters people it doesn't recognize."
-- Today, it's a squirrel terrorizing the neighborhood, tomorrow, it's a group of gang-affiliated kittens.
|7:12:18 PM, Wednesday, March 16, 2011|
Speed Demon Creates a Shock
|11:57:51 AM, Wednesday, March 16, 2011|
“Just as some drivers obey the speed limit while others treat every road as if it were the Autobahn, some stars move through space faster than others. NASA's Wide-field Infrared Survey Explorer, or WISE, captured this image of the star Alpha Camelopardalis, or Alpha Cam, in astronomer-speak, speeding through the sky like a motorcyclist zipping through rush-hour traffic. The supergiant star Alpha Cam is the bright star in the middle of this image, surrounded on one side by an arc-shaped cloud of dust and gas -- a bow shock -- which is colored red in this infrared view.
Such fast-moving stars are called runaway stars. The distance and speed of Alpha Cam is somewhat uncertain. It is probably somewhere between 1,600 and 6,900 light-years away and moving at an astonishing rate of somewhere between 680 and 4,200 kilometers per second (between 1.5 and 9.4 million mph). It turns out that WISE is particularly adept at imaging bow shocks from runaway stars. Previous examples can be seen around Zeta Ophiuchi , AE Aurigae, and Menkhib. But Alpha Cam revs things up into a different gear. To put its speed into perspective, if Alpha Cam were a car driving across the United States at 4,200 kilometers per second, it would take less than one second to travel from San Francisco to New York City!
Astronomers believe runaway stars are set into motion either through the supernova explosion of a companion star or through gravitational interactions with other stars in a cluster. Because Alpha Cam is a supergiant star, it gives off a very strong wind. The speed of the wind is boosted in the forward direction the star is moving in space. When this fast-moving wind slams into the slower-moving interstellar material, a bow shock is created, similar to the wake in front of the bow of a ship in water. The stellar wind compresses the interstellar gas and dust, causing it to heat up and glow in infrared. Alpha Cam's bow shock cannot be seen in visible light, but WISE's infrared detectors show us the graceful arc of heated gas and dust around the star.
JPL manages and operates the Wide-field Infrared Survey Explorer for NASA's Science Mission Directorate, Washington. The principal investigator, Edward Wright, is at UCLA. The mission was competitively selected under NASA's Explorers Program managed by the Goddard Space Flight Center, Greenbelt, Md. The science instrument was built by the Space Dynamics Laboratory, Logan, Utah, and the spacecraft was built by Ball Aerospace & Technologies Corp., Boulder, Colo. Science operations and data processing take place at the Infrared Processing and Analysis Center at the California Institute of Technology in Pasadena. Caltech manages JPL for NASA. “
Nuclear Powerhouse: Now Is The Time For The Next Atomic Boom
|10:35:39 PM, Tuesday, March 15, 2011|
“France’s most powerful businesswoman believes now is the time for the next atomic boom.
The Middle East is in turmoil, oil prices have skyrocketed, the cost of gas is through the roof. All of which is good news—if you’re Anne Lauvergeon.
Lauvergeon may be the world’s most effective proselytizer for nuclear energy. “Atomic Anne,” as she’s known, heads France’s Areva, the largest builder of nuclear reactors on the planet. The 51-year-old executive, a perennial member of the Forbesmost-powerful-women list (recently outranking Melinda Gates, Meg Whitman, and Queen Elizabeth, though trailing Lady Gaga), has been the guiding force behind her country’s massive push into nuclear energy, which today fuels 75 percent of all its electricity. And now, she believes, nuclear’s next big global moment has arrived. “The cheap price of oil and gas is over for the future,” she tells NEWSWEEK. “Nuclear isn’t the only solution, but it is part of the solution.”
The world may still need convincing.
While a handful of countries rely primarily on nuclear power—tiny Lithuania is 85 percent nuclear—resistance remains strong elsewhere. In the U.S., which is just 20 percent nuclear-powered, President Obama has championed it as a way to wean the country off fossil fuels, devoting $36 billion of his latest budget to nuclear projects. But despite somewhat successful efforts to rebrand nuclear as a clean-energy source, the industry hasn’t fully outgrown the stigma of the 1979 Three Mile Island disaster.
If Lauvergeon is correct that now is a turning point, the timing couldn’t be better for her. The hard-charging CEO has morphed from a media darling in her home country (“You can’t fire me. I am an icon in this country,” she reportedly told a minister who criticized her) to an embattled titan, following missteps that included the loss of a $40 billion nuclear project in Abu Dhabi. She has until June, when her current mandate expires, to turn things around—or she will be removed from the government-controlled Areva by French President Nicolas Sarkozy, who has been a major supporter but appears to have soured on her. “We have transformed this company,” she says in her defense, pointing to major expansion into the U.S., China, Japan, India, and the Middle East…”
'Mario' - Live Action Film Trailer
|3:48:59 PM, Tuesday, March 15, 2011|
-- Incontestably the best movie to come out this year. Brilliance.
Mushroom Cloud Play/Tree House
|1:42:04 PM, Tuesday, March 15, 2011|
-- ""We experience a contradiction between what our eyes enjoy and what our mind knows."- Dietrich Wegner
At first glance, this happy-go-lucky playhouse could look like any child's dream. But then, the shape reminds us of a mushroom cloud and we're left feeling a little uneasy...
"In Playhouse, I combine an atomic bomb’s mushroom cloud, with one of the safest places one can go, their childhood playhouse," artist Dietrich Wegner tells us. "The playhouse is a place of escape, imagination, and comfort. Often we have used bombs to preserve our playhouse, causing us to be stuck in limbo, between comfort and fear. I question how mindful we are of the consequences of our actions. I search for images that articulate the confusion between the intentions, outcomes and ideals of my nation, while focusing on the spaces between beauty, fantasy, and reality.
"I make my statement from confusion with what I see around me. I want to make images that help me think around my world, so I can, in the end, know what I see a little better. I hope my work helps people think about our collective fears, our innocence and the decisions we make to be safe. My hope is that we climb above our terror enough to think about the reality and consequences of our actions."
When asked what kind of reaction Playhouse has received, here's what Wegner said. "Unfortunately, at least judging from blog reactions to Playhouse , people just seem to think it is cool fun and cozy and I am not sure internet viewers get farther than that.""
China’s Highly Unequal Economy
|1:35:06 PM, Tuesday, March 15, 2011|
"Double-digit growth can’t hide the fact that China’s state-controlled economy is leaving the vast majority of citizens behind.
During a round table with business leaders during Chinese President Hu Jintao’s visit to the United States in January, US President Barack Obama stated optimistically that ‘With China’s growing middle class, I believe that over the coming years, we can more than double our exports to China and create more jobs here in the United States.’ To be sure, that is a reasonable expectation. When other Asian economies like Japan and Korea grew toward the GDP per capita level of $10,000, sizable middle class populations did indeed emerge.
However, when looking under the bonnet at China’s economic engine, it’s clear that a growing middle class with rising disposable income and consumption is missing. Instead, there’s an economy that is still dominated by state owned firms and state-led investment, as well as by rapidly rising inequality. Instead of an enlarging urban middle class, China is increasingly splitting into a small upper class that spends freely on luxury goods, and a remaining population whose earnings and savings are eroded by inflation and state confiscation.
The underlying dynamics are clear in a recent statistical release by the government. First, real urban disposable income rose a comparatively tepid 7.8 percent in 2010, despite economic growth of nearly 10 percent. However, urban retail sales of consumer goods grew 14.5 percent. While the growth of consumption is good for China's economy, the pattern of this growth suggests rising inequality.
The biggest growth in consumption included jewellery (46 percent), furniture (37 percent), cars (34 percent) and construction material (34 percent). Essentially, these are items related to the spending of the upper class. These ‘consumer’ goods also made up 33 percent of all retail consumption in China. The large size and strong growth in luxury items implies that grey income was substantial in 2010, as suggested by a Credit Swiss report authored by Prof. Wang Xiaolu.
In this report, released last year and based on a survey of urban households in 2009, Wang found nearly 1.5 trillion dollars in grey income unreported in the official household income numbers. He further found that over 60 percent of this grey income accrued to the top 10 percent of households. The latest numbers also suggest that while income of normal households likely grew at around 8 percent, the top 10 percent of households may have seen income growth above 25 percent.
A growing middle class is also absent among recent college graduates. According to the Ministry of Education, only 68 percent of college graduates in 2010 were able to find permanent employment. Even among those who found employment, wages were often no better or sometimes even worse than those for migrant workers in factories. Unlike the rest of the world, however, China enjoyed a spectacular 10 percent growth rate. This impressive growth, however, didn’t translate to high paying jobs for college graduates. In major cities, many college graduates live as an ‘ant tribe,’ packed tightly in small dormitory rooms with four or more roommates..."
Trike Drifting Documentary
|12:57:43 AM, Tuesday, March 15, 2011|
Libya Fight Photos
|12:39:38 AM, Tuesday, March 15, 2011|
Japan Earthquake: Before and After Aerial Photos
|11:44:00 PM, Monday, March 14, 2011|
-- "Aerial photos taken over Japan have revealed the scale of devastation across dozens of suburbs and tens of thousands of homes and businesses."
5,300-Year-Old Iceman Mummy Gets a Makeover
|11:00:32 PM, Monday, March 14, 2011|
“Iceman, a 5,300-year-old mummy also called Ötzi and discovered in the Alps, is showing a new face to the world at the Italian museum where he resides.
The South Tyrol Museum of Archaeology commissioned two reconstruction artists, Dutch brothers Adrie and Alfons Kennis, to recreate the mummy's face using both art and forensic science, including three-dimensional images of his skull.
The finished face reveals a man with deep-set eyes, a long nose, weathered skin and hair that appears to be on its way to dreads.
Ötzi was discovered in 1991 by hikers in the Ötztal Alps along the Austrian-Italian border. Since then, researchers have mined his remains, the artifacts buried with him and his burial site for clues about his life (he lived sometime between 3350 and 3100 B.C.), death and descendants.
Over the years, research has added many details, putting his age at 46, a long life for a man in the Copper Age. Scientists have also pinpointed his cause of death as blood loss caused by an arrow wound to his left shoulder. However, the question "What did he look like?" has remained elusive, according to the museum.
As such, Ötzi has inspired many reconstructions and artistic interpretations. These include a work by the British artist Marilène Oliver, who translated a CT scan of the body into point plots. She drilled them into acrylic sheets, which she layered and fused to create a ghostlike 3-D representation.
The new reconstruction is part of the exhibit currently on view at the museum – "Ötzi20 - Life. Science. Fiction. Reality" – celebrates the first 20 years of the iceman's second life. It includes an exploration of media coverage and images of Ötzi, according to a press release.”
Astronomy Picture of the Day: NGC 1499, The California Nebula
|9:12:53 PM, Monday, March 14, 2011|
-- "What's California doing in space? Drifting through the Orion Arm of the spiral Milky Way Galaxy, this cosmic cloud by chance echoes the outline of California on the west coast of the United States. Our own Sun also lies within the Milky Way's Orion Arm, only about 1,500 light-years from the California Nebula. Also known as NGC 1499, the classic emission nebula is around 100 light-years long. On many images, the most prominent glow of the California Nebula is the red light characteristic of hydrogen atoms recombining with long lost electrons, stripped away (ionized) by energetic starlight. In the above image, however, hydrogen is colored green, while sulfur is mapped to red and oxygen mapped to blue. The star most likely providing the energetic starlight that ionizes much of the nebular gas is the bright, hot, bluish Xi Persei, just outside the right image edge. A regular target for astrophotographers, the California Nebula can be spotted with a wide-field telescope under a dark sky toward the constellation of Perseus, not far from the Pleiades."
Solar Power Breakthrough Claimed By Stanford Researchers
|9:04:27 PM, Monday, March 14, 2011|
“It’s the Holy Grail at clean energy research labs all over the world and something which could address long term energy issues domestically and beyond: more efficient photovoltaic solar. We’ve told you about scientists studying full-spectrum cells, using textured substrates, trying self-regenerating nanomaterials – we’ve even reported on an anti-reflective film inspired by a coating found in moth eyes. Now a Stanford team is claiming a breakthrough in making cheaper, more efficient panels by adding a single layer of organic molecules to solar cells.
The researchers studied this technique on a fairly new type of solar cell that uses tiny particles of semiconductors called quantum dots. Quantum dot solar cells are cheaper to produce than traditional silicon cells, but they haven’t caught on due to their relative inefficiency.
For Stacey Bent, a chemical engineering professor at Stanford, this represented something of a challenge. She knew that solar cells made of a single material have a maximum efficiency of about 31 percent, a limitation of the fixed energy level they can absorb, and that quantum dot solar cells didn’t share this limitation. “Quantum dots can be tuned to absorb a certain wavelength of light just by changing their size,” the Stanford report on her research says. “And they can be used to build more complex solar cells that have more than one size of quantum dot, allowing them to absorb multiple wavelengths of light.”
So Bent and her team coated a titanium dioxide semiconductor in their quantum dot solar cell with a very thin single layer of organic molecules. They found that just that single layer, less than a nanometer thick, was enough to triple the efficiency of the solar cells.
Even with this breakthrough, there’s still work to do: Bent said the cadmium sulfide quantum dots she’s been using aren’t ideal for solar cells, so her group plans to try other molecules for the organic layer, while also tinkering with the solar cell increase light absorption.
Her theory is, said Stanford, that once the sun’s energy creates an electron and a hole, the thin organic layer helps keep them apart, preventing them from recombining and being wasted. The group has yet to optimize the solar cells, and they have currently achieved an efficiency of, at most, 0.4 percent. But the group can tune several aspects of the cell, and once they do it is said, the threefold increase caused by the organic layer would be even more significant.”
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