Thursday, 16 September 2010

Johnald's Fantastical Daily Link Splurge

Johnald's Fantastical Daily Link Splurge


Top Microphotos of Life Beginning

Posted: 16 Sep 2010 04:00 AM PDT

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Izpisua_17633_1

There are many things that look amazing, mysterious or beautiful under the microscope, but there are few things that beat a close-up look at life emerging.

Some of the winning images in this year's Nikon's Small World photomicrography contest capture some of the first moments inside the eggs of animals including starfish and butterflies.

I was lucky enough to be one of the judges for this year's competition, and among the most memorable of the 2,200 entries were images of the first few cells at the very beginning of an organism's life. I've gathered some of the best microphotographs of these early moments in this gallery.

The order of all the winning images won't be revealed until Oct. 13, but in the meantime, you can choose your favorite and help determine the winner of the public vote.

Mouse Embryo Stem Cells Surrounded by Trophectoderm Cells

Juan Carlos Izpisúa, Centre de Medicina Regenerativa de Barcelona

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EPA’s Pollution-Busting Cops Have Lost Focus, Say Watchdogs

Posted: 15 Sep 2010 12:53 PM PDT

The federal government's anti-pollution detectives have lost their focus, allege government watchdog group Public Employees for Environmental Responsibility.

According to documents obtained by Peer under the Freedom of Information Act, the Environmental Protection Agency's investigation unit is understaffed and referring fewer cases for federal prosecution than during the Bush administration.

"We've been contacted by special agents in the EPA's Criminal Investigation Division saying they feel that the program is headed in the wrong direction," said Peer executive director Jeff Ruch.

Peer's announcement, which came days before the 40th anniversary of the EPA's Clean Air Act, is the latest in a series of CID controversies.

During the Bush administration, when the EPA at large was under political pressure to skew many of its scientific decisions in favor of industry, CID investigators were assigned such environmentally-unrelated activities as providing security at Super Bowls and all-star games.

Rather than pursuing corporate wrongdoers, some of the agency's elite, badge-carrying agents became personal errand-runners for then-EPA chief Christie Todd Whitman, who used them to pick up laundry and walk her dogs.

Backlash sparked by attention from Peer and other activists prompted review, and the EPA under President Obama has — despite concerns over chief Lisa Jackson's industry ties and prior pollution enforcement record — been far truer to its mission.

But according to Peer, much work remains to be done.

"The overall point that agents are bringing to us is that the management of CID has lost focus on environmental prosecution as the purpose of the program," said Ruch. "Things are adrift."

Employment records released by the EPA to Peer show that in June, there were just 173 CID investigators (.pdf), well below the 200 required by the U.S. Pollution Protection Act of 1990 and fewer than the 180 investigators employed at the end of the Bush administration.

"You'd think that to the extent you're going to do more enforcement, having more investigators would be a good idea," said Ruch.

According to an EPA statement relayed by agency spokesperson Stacy Kika, those numbers were accurate when sent to Peer in June but no longer apply. "With recent hires, EPA currently has 192 agents in its Criminal Investigative Division and another 20 in the pipeline," said the EPA.

Peer's documents also show that CID referred only 339 cases for federal prosecution (.pdf) in 2009, well below the Bush administration average of 365 cases per year. The agency doesn't conduct prosecutions itself, but suggests candidates for legal action to the Department of Justice.

The EPA replied that it had opened 387 cases in 2009, the highest number in five years. But Ruch said that cases referred are a far more meaningful number.

"Opening a case just means that you've started an investigation, which may or may not be concluded, which may or may not be referred for prosecution," he said. "We're focusing on the number of cases that EPA took to the Justice Department and said, 'You should prosecute.'"

Stated the agency, "Special agents are carefully allocating our finite resources by going after the biggest, most serious offenders."

Peer will deliver further critiques of CID in coming months, said Ruch.

"What we're hearing, on an anecdotal basis, is that a lot of the focus is on bureaucratic minutiae, at the expense of putting polluters in jail," he said.

Image: Chemical waste on a beach in Lake Charles, Louisiana photographed in 1972 by Marc St. Gil as part of the EPA's Documerica project.

See Also:

Brandon Keim's Twitter stream and reportorial outtakes; Wired Science on Twitter. Brandon is currently working on an ecological tipping point project.

Glaciers Help Mountains Grow

Posted: 15 Sep 2010 10:53 AM PDT

Glaciers can help mountains grow by shielding them from erosion.

The finding contradicts the usual view of glaciers as icy razors that slowly scrape mountains away. But the new data, collected from rocks in the Andes Mountains in the Patagonia region of South America, shows glaciers can both protect and destroy.

"Usually glaciers are considered a powerful agent of erosion that carve mountains out, build deep valleys, and help destroy mountains," said geologist Stuart Thomson of the University of Arizona, lead author of the new study in the Sept. 16 issue of Nature. "But what we're finding in Patagonia is that the mountains haven't eroded at all."

Mountains are formed when two continental plates smash together, thrusting the crust upward. This process is ongoing in several of Earth's mountain ranges, including the Andes.

But when mountain glaciers appeared around 3 million to 5 million years ago, they started grinding away at the rocky peaks as they grew, and flowed slowly downhill, carving them into their present jagged shapes. A mountain's ultimate height and width is a balancing act between uplift from the Earth and wear-down from the ice.

The Andes were considered the textbook example of this effect, dubbed the "glacial buzzsaw." But some of Thomson's colleagues built computer models that suggested mountains could continue to grow under a glacier's protective cover.

"If you shut down erosion, stop the mountain from eroding away, the mountains all grow," Thomson said. "There were some papers a few years ago that postulated this idea. But no one had actually seen it in the real world."

To test the models, Thomson and colleagues journeyed through the fjords of Patagonia on small boats rented from local fishers. They sailed through the same channels that Charles Darwin traveled on the Beagle. Several landforms there are named for him and his crew.

Thomson and colleagues used hammers to break off football-sized slabs of granite. When the geologists got back to the lab, they ground the rocks up and picked out small crystals of a mineral called apatite, which is made of stuff similar to tooth enamel.

The researchers hand-picked 146 apatite crystals, each less than 0.1 millimeter long, and analyzed them for evidence of radioactive elements decaying within them. When uranium decays to lead, a natural process that happens at a steady rate, the split leaves a tiny track in the apatite that is visible under a microscope.

But these tracks are erased when the crystal is heated above 212 degrees Fahrenheit, the temperature of rock 2.5 miles deep in the Earth. Counting the number of tracks lets geologists back-calculate the last time that the rock was that hot, and therefore how long ago it emerged from the Earth.

"If the rocks are very old, erosion is very slow. It's taken a long time to come from 4 kilometers to the surface," Thomson said. "But a young age, around 1 million years, shows the erosion rate is very fast."

To check their calculations, the team used a similar dating technique that involved measuring the amount of helium in the crystals, a record of the last time the rocks were 158 degrees Fahrenheit.

Both methods gave nearly the same results: North of about 45 degrees latitude, the rocks showed that erosion started accelerating between 5 million and 7 million years ago, around the time when the Patagonian glaciers formed. This means the buzzsaw was active in the north.

But south of 45 degrees, where the mountains are about 3,000 feet higher, all the rocks were older than 10 million years. The buzzsaw somehow turned off.

"It was quite a surprising thing," Thomson said. "Our original motivation was to look at how the glaciers destroy the mountain. We were expecting to see lots of erosion in the south."

Whether glaciers cut or coddle the mountains below depends on climate, Thomson says. In the southern part of Patagonia, the climate is much colder, and the glaciers move much more slowly.

"We call this glacial armoring because it's actually protecting the mountains from erosion and allowing them to grow much higher than they would have normally," Thomson said.

Some models suggest that the glaciers actually stick to the rocks and don't move at all. Large ice sheets like those that covered North America and northern Europe during the last ice age were known to be frozen to the ground below, says geologist Jean Braun of Joseph Fourier University in Grenoble, France, who was not involved in the new work.

"However, that mountain glaciers (i.e., those usually fast flowing along and eroding mountainsides) would be frozen to the bedrock and thus protect mountain topography had never been demonstrated," he told Wired.com in an e-mail. The new study is "very important," he said, because it is "one of the best proof[s] to date that the link between climate and mountain-belts dynamics is real and quantifiable."

Images: 1) South flank of Cordillera Darwin (elevation 2,488 m), the highest point on Tierra del Fuego, Chile (photo taken from the Beagle Channel). Credit: Stuart Thomson. 2) Nature/Jean Braun. 3) Geologists transfer from research vessel "The Foam" to shore in a Zodiac in front of the north side of Cordillera Darwin. Credit: Stuart Thomson.

See Also:

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