Melting Arctic Sea Ice Drives Walruses onto Land

Fast-melting Arctic sea ice appears to be pushing walruses to haul themselves out onto land, and many are moving around the area where oil leases have been sold, the U.S. Geological Survey reports.

By Deborah Zabarenko, Environment Correspondent

WASHINGTON (Reuters) – Fast-melting Arctic sea ice appears to be pushing walruses to haul themselves out onto land, and many are moving around the area where oil leases have been sold, the U.S. Geological Survey reports.

Walruses are accomplished divers and frequently plunge hundreds of feet (meters) to the bottom of the continental shelf to feed. But they use sea ice as platforms to give birth, nurse their young and elude predators, and when sea ice is scarce or non-existent, as it has been this summer, they come up on land.

Last September, the loss of sea ice caused an estimated 10,000 to 20,000 walruses to venture onto land, and as sea ice melts reached a record last month, U.S. government scientists are working with Alaskan villagers to put radio transmitters on some of the hauled-out walruses to track their movements around the Chukchi Sea.

“The ice is very widely dispersed and there is little of it left over the continental shelf,” researcher Chad Jay of the U.S. Geological Survey said in a statement on Wednesday. “Based on our tracking data, the walruses appear to be spreading out and spending quite a bit of time looking for sea ice.”

The loss of sea ice puts Pacific walruses at risk, according to the U.S. Fish and Wildlife Service, but other, higher-priority species will get attention first. In February, the wildlife service listed Pacific walruses as candidates for protection, though not protection itself.

Walruses are protected under the Marine Mammal Protection Act, which means these animals cannot be harvested, imported, exported or be part of interstate commerce.

Polar bears, which also use sea ice in the Chukchi Sea as platforms for hunting, have been designated as threatened under the U.S. Endangered Species Act because of declining sea ice in the Arctic.

Compared to last year’s massive haul-out, there are few walruses on land, and there is no solid count, Jay said.

“There is a lot less ice than there used to be on the continental shelf this time of year,” he said. “So we might be headed into a new normal.”

Transmissions from the radio-tagged walruses offer a good picture of where these creatures are in the Chukchi Sea in a U.S. Geological Survey graphic updated approximately weekly.

SHRINKING ARCTIC SEA ICE
Available online at http://alaska.usgs.gov/science/biology/walrus/2011animation_Norseman.html, the graphic shows where the walruses were when they were first tagged (shown as red Xs) and how they moved around the water (shown as yellow dots).

The graphic also shows changes in sea ice cover in the far north, indicating nearly ice-free conditions in areas where the walruses are moving. Many are within the boundaries of an oil lease sale area that stretches along the northwestern Alaska coast and far into the Chukchi Sea.

Royal Dutch Shell, ConocoPhillips and Statoil hold leases in the Chukchi Sea, though no drilling has started.

Last month saw Arctic sea ice drop to its lowest extent — meaning that it covered the smallest area — for any July since satellite records began in 1979, according to the U.S. National Snow and Ice Data Center. Typically, Arctic sea ice hits its lowest extent for the year in September.

This record-low ice extent for July is lower than July ice extent in 2007, when ice extent shrank in September to its smallest area in the satellite record.

(Editing by Sandra Maler)

IBM produces first ‘brain chips’

IBM's processors replicate the system of synaptic connections found in the human brain.

IBM has developed a microprocessor which it claims comes closer than ever to replicating the human brain.

The system is capable of “rewiring” its connections as it encounters new information, similar to the way biological synapses work.

Researchers believe that by replicating that feature, the technology could start to learn.

Cognitive computers may eventually be used for understanding human behaviour as well as environmental monitoring.

Dharmendra Modha, IBM’s project leader, explained that they were trying to recreate aspects of the mind such as emotion, perception, sensation and cognition by “reverse engineering the brain.”

The SyNAPSE system uses two prototype “neurosynaptic computing chips”. Both have 256 computational cores, which the scientists described as the electronic equivalent of neurons.

One chip has 262,144 programmable synapses, while the other contains 65,536 learning synapses.

Man machine
In humans and animals, synaptic connections between brain cells physically connect themselves depending on our experience of the world. The process of learning is essentially the forming and strengthening of connections.

A machine cannot solder and de-solder its electrical tracks. However, it can simulate such a system by “turning up the volume” on important input signals, and paying less attention to others.

IBM's processor replicates the synaptic connections between neurons found in the brain.

IBM has not released exact details of how its SyNAPSE processor works, but Dr Richard Cooper, a reader in cognitive science at Birkbeck, University of London said that it likely replicated physical connections using a “virtual machine”.

Instead of stronger and weaker links, such a system would simply remember how much “attention” to pay to each signal and alter that depending on new experiences.

“Part of the trick is the learning algorithm – how should you turn those volumes up and down,” said Dr Cooper.

“There’s a a whole bunch of tasks that can be done just with a relatively simple system like that such as associative memory. When we see a cat we might think of a mouse.”

Some future-gazers in the cognitive computing world have speculated that the technology will reach a tipping point where machine consciousness is possible.

However, Dr Mark Bishop, professor of cognitive computing at Goldsmiths, was more cautious.

“[I] understand cognition to be something over and above a process simulated by the execution of mere computations, [and] see such claims as verging on the magical,” he said.

IBM’s work on the SyNAPSE project continues and the company, along with its academic partners, has just been awarded $21m (£12.7m) by the US Defense Advanced Research Projects Agency (DARPA).

What’s the age of the moon? It could be waning

the full moon rises behind the ancient temple of Posseidon (AP Photo/Petros Giannakouris)


WASHINGTON (AP) — That old moon might not be as antique as we thought, some scientist think. They say it’s possible that it isn’t a day over 4.4 billion years old.

But other astronomers disagree with a new study’s conclusions. They think the moon is up to its typical age-defying tricks and is really pushing 4.6 billion as they have suspected all these years.

Either way, the new analysis of an important moon rock brought back by the Apollo 16 mission is showing that the moon isn’t ready to give up its true age and origins quite yet, even though scientists thought they had it all figured out a decade or two ago.

“It’s not as ancient as we might think,” said study chief author Lars Borg, a geochemist at the Lawrence Livermore National Lab. His study appears online Wednesday in the journal Nature.

The study uses new techniques and radioactive isotopes of lead and other elements to date the moon rock at 4.4 billion years old. What’s key is that this is a special type of rock that would have floated up to the moon’s crust soon after its theorized ocean of molten rock cooled. That supposedly happened soon after the moon formed as a result of a spectacular crash between Earth and a planet. The chunks that broke off formed the moon.

That means there are two possibilities, Borg said. Either the moon is 200 million years younger or the accepted theory of a molten rock ocean on the moon is wrong, he said.

Borg acknowledges that some moon rocks have been dated at nearly 4.6 billion years old. But those conclusions could be wrong because of weaker rock dating techniques used in the past, he said.

Outside scientists said Borg did good work coming up with a date for the Apollo 16 rock but may have jumped to the wrong conclusion on lunar age or origins. They said it’s possible that the rock is from a smaller molten rock ocean or was created when the moon was bombarded by space debris which was much more common a few billion years ago.

Borg’s conclusion “is a little bit fancy for my taste,” said Erik Asphaug of University of California, Santa Cruz, who recently published a theory that Earth used to have a second smaller moon until it crashed into the bigger one.

MIT astronomer Maria Zuber called the study in Nature “very puzzling.”

Caribbean Coral Catch Disease From Sewage

Healthy elkhorn coral is found on Sombrero Reef in the Florida Keys National Marine Sanctuary. In the past 15 years, almost 90 percent of elkhorn populations in the Florida Keys have died, landing this once-common coral on the endangered species list.

Human beings occasionally get diseases from animals, such as swine flu, rabies and anthrax. A new study finds that humans can also spread disease to wildlife, with grim results. A bacterium from our guts is now rampaging through coral reefs in the Caribbean.

Those reefs were already in slow decline, but they took a huge hit starting in 1996, when a disease called white pox appeared in the Florida Keys.

“Since that time, elkhorn coral — the species it affects — has declined 88 percent in the Florida Keys,” says Kathryn Sutherland, a reef ecologist at Rollins College in Florida. “And we’ve seen similar declines elsewhere in the Caribbean.”

The coral is named for its resemblance to elk antlers, and is among the most important reef-building species in the Caribbean. Sutherland and her colleagues soon found a culprit for the die-off — a bacterium called Serratia marcescens. It also happens to cause disease in human beings, notably hospital infections. But the scientists couldn’t prove cause and effect.

“In 2002, we could only speculate that human waste was the source of the pathogen because the pathogen is also found in the guts of other animals,” such as deer, Sutherland says.

So she and some colleagues exposed the coral in the laboratory to bacteria extracted from sewage. As they report in the journal PLoS ONE, the coral got the pox within days.

“That gave us definitive evidence that white pox disease is caused by a pathogen found in human sewage.”

An ‘Evolutionary Triple Jump’
Traditionally, we think of diseases moving from animals to us, but “this is almost a man-bites-dog story,” says James Porter at the University of Georgia, a co-author of the study.

“This is a very rare and unusual evolutionary triple jump,” Porter says. The bacterium “went from humans to the lower invertebrates — coral. It went from the terrestrial environment to the marine environment. And then it went from the anaerobic [low oxygen] conditions of our stomach to the fully oxygenated conditions on the reef.”

Porter says they are still trying to explain exactly how the bacterium makes coral sick, and why white pox appeared so suddenly and viciously. The good news is those answers aren’t needed to protect coral. You can just keep the germ away. And, happily, that’s been happening along the Florida Keys.

Jay Gewin, utilities manager in the city of Key West, says residents there voted to upgrade their leaky sewer system. It was not done to save coral per se, but to get rid of health warnings that were keeping the tourists away.

“In the early 2000s when this was such a problem, every single beach in the city of Key West would have an advisory,” Gewin says.

Those health warnings on the beach are now rare, thanks to a sophisticated new wastewater system that cost the city more than $70 million.

“The wastewater is treated to the highest level in the state of Florida, and then it goes into a deep injection well, where the treated final water product is sent thousands of feet down into the ground,” Gewin says.

Eventually it may seep back up into the ocean, but he says by then it’s clean. The biologists say that since the new system was installed, there haven’t been any further die-offs of elkhorn coral around Key West. Other towns along the Keys are now in the process of cleaning up their act, too.

“But this is a problem Caribbean-wide,” Sutherland says, “and there’s a widespread lack of wastewater treatment in the wider Caribbean region.”

And that’s bad news for the elkhorn coral. Due largely to the disease spreading from humans, it’s been tagged as vulnerable on the endangered species list.

Critters moving away from global warming faster

This is a photograph of a comma butterfly, which has moved north 135 miles in just 21 years in Great Britain. (AP Photo/Butterfly Conservation, Jim Asher)...

WASHINGTON (AP) — Animals across the world are fleeing global warming by heading north much faster than they were less than a decade ago, a new study says.

About 2,000 species examined are moving away from the equator at an average rate of more than 15 feet per day, about a mile per year, according to new research published Thursday in the journal Science which analyzed previous studies. Species are also moving up mountains to escape the heat, but more slowly, averaging about 4 feet a year.

The species — mostly from the Northern Hemisphere and including plants — moved in fits and starts, but over several decades it averages to about 8 inches an hour away from the equator.

“The speed is an important issue,” said study main author Chris Thomas of the University of York. “It is faster than we thought.”

Included in the analysis was a 2003 study that found species moving north at a rate of just more than a third of a mile per year and up at a rate of 2 feet a year. Camille Parmesan of the University of Texas, who conducted that study, said the new research makes sense because her data ended around the late 1990s and the 2000s were far hotter.

Federal weather data show the last decade was the hottest on record, and 2010 tied with 2005 for the hottest year on record. Gases from the burning of fossil fuel, especially carbon dioxide, are trapping heat in the atmosphere, warming the Earth and changing the climate in several ways, according to the overwhelming majority of scientists and the world’s top scientific organizations.

As the temperatures soared in the 2000s, the species studied moved faster to cooler places, Parmesan said. She pointed specifically to the city copper butterfly in Europe and the purple emperor butterfly in Sweden. The comma butterfly in Great Britain has moved more than 135 miles in 21 years, Thomas said.

It’s “independent confirmation that the climate is changing,” Parmesan said.

One of the faster moving species is the British spider silometopus, Thomas said. In 25 years, the small spider has moved its home range more than 200 miles north, averaging 8 miles a year, he said.

Stanford University biologist Terry Root, who wasn’t part of this study but praised it as clever and conservative, points to another species, the American pika, a rabbitlike creature that has been studied in Yellowstone National Park for more than a century. The pika didn’t go higher than 7,800 feet in 1900, but in 2004 they were seen at 9,500 feet, she said.

For Thomas, this is something he notices every time he returns to his childhood home in southern England. The 51-year-old biologist didn’t see the egret, a rather warm climate bird, in the Cuckmere Valley while growing up. But now, he said, “All the ditches have little egrets. It was just a bizarre sight.”

Thomas plotted the movement of the species and compared it to how much they would move based on temperature changes. It was a near perfect match, showing that temperature changes explain what’s happening to the critters and plants, Thomas said. The match wasn’t quite as exact with the movement up mountains and Thomas thinks that’s because species went north instead or they were blocked from going up.

Thomas found that the further north the species live, the faster they moved their home base. That makes sense because in general northern regions are warming more than those closer to the equator..

Conservation biologist Mike Dombeck, a former U.S. Forest Service chief, said changes in where species live — especially movements up mountains — is a problem for many threatened species.

Thomas said what he’s studied isn’t about some far off problem.

“It’s already affected the entire planet’s wildlife,” Thomas said in a phone interview. “It’s not a matter that might happen in the lifetime of our children and our grandchildren. If you look in your garden you can see the effects of climate change already.”

The Darkest World: Scientists Discover ‘Darth Vader’ Planet

The distant exoplanet TrES-2b, shown here in an artist's conception, is darker than the blackest coal. It refuses to give back light. Why? That's a mystery

The polarities of darkness and light have been central to human cultural imaginings since our origins.

In the 5th century B.C. there was Zoroastrian religion, based on the eternal battle between darkness (evil) and light (spiritual purity). In the modern world we have the mythic conflict between Luke Skywalker in his white tunic and his black-shrouded, fallen father, Darth Vader. Given our penchant for pulling the world apart into this kind of dichotomy, it is, perhaps, no wonder that the recent discovery of the darkest of dark planets has made news.

A few weeks ago, two astronomers announced the discovery of TrES-2b via the Kepler spacecraft. The planet is a so-called “Hot Jupiter” — a large gas giant orbiting extremely close to its sun-like star (the whole system is about 750 light years away from us).

What makes TrES-2b so remarkable is its refusal to give back light. The scientific word for reflectivity is albedo. The Earth reflects about 37 percent or 0.37 of the light it receives from the sun. That is why we present such a beautiful bright blue face to the universe.

TrES-2b is another story entirely. It bounces back less than 1 percent (0.01) of the light it receives from its star. That means the planet is blacker than coal. Seen from space, TrES-2b would barely be visible.

It is not clear yet why TrES-2b is so dark. It may be that the intense heat from the nearby star has formed strange, light-absorbing compounds in the planet’s atmosphere.

“It’s a mystery as to what’s causing it to be so dark,” co-discover David Kipping told Space.com. “There’s a good chance it’s a chemical we haven’t even thought of yet.”

A world darker than coal, darker than night and darker than the heart of wickedness. You can provide your own metaphor, analogy or back story if you want.

One of the great beauties of science is the way it lets us discover how much richer the world is than our imagination might have conceived. Then our imaginations find their own uses for these discoveries, making the world we find our own.

You can keep up with more of what Adam Frank is thinking on Facebook.

New Mechanism of Genomic Instability Revealed

ScienceDaily (Aug. 18, 2011) — Researchers at NYU School of Medicine have discovered the cellular mechanisms that normally generate chromosomal breaks in bacteria such as E. coli. The study’s findings are published in the August 18 issue of the journal Cell.

“This study provides a new explanation on how bacteria generate mutations and adapt to stressors like antibiotics. The study is quite unusual as it touches on several different fields of molecular biology at the same time: replication, transcription, translation and DNA repair,” said Evgeny Nudler, PhD, Julie Wilson Anderson Professor of Biochemistry, NYU School of Medicine and co-author of the study.

The study examines the collision of three major cellular moving “machines”: replisome — a protein complex responsible for DNA synthesis, RNA polymerase — an enzyme responsible for RNA synthesis, and ribosome — a molecular structure responsible for protein synthesis. Collisions between replisome and RNA polymerase occur frequently in cells because the two machineries share the same DNA track, but the speed of the replisome is much faster than that of RNA polymerase. However, the consequences of such collisions remained unknown.

Researchers designed an experimental system to directly monitor co-directional and head-on collisions between the replisome and RNA polymerase in living cells under various conditions of growth.

Researchers found co-directional collisions lead to DNA double strand breaks (DSBs) or mutations. Importantly, however, such DSBs appear only if the replisome collides with backtracked RNA polymerase.

Backtracking, or backward sliding of RNA polymerase along RNA and DNA, is an intrinsic property of all cellular RNA polymerases from bacteria to humans. Multiple anti-backtracking mechanisms that employ various transcription factors exist in bacteria and nucleus-containing cells, including human cells.

Researchers demonstrated that the cooperation between translating ribosomes and RNA polymerase is central in the maintenance of genomic stability because it prevents backtracking.

The implication of these findings is significant as the ribosome is the primary sensor of cellular metabolism and stress. It has been well established that stress-induced mutagenesis is activated in response to adverse conditions, such as starvation or antibiotics. The development of mutations depends on error-prone DSB repair, which accelerates adaptation to environmental changes, such as acquisition of resistance to antibiotics. In this respect, the backtracking-based mechanism of DSB may account for stress-driven evolution in bacteria.

“Because the organization of replisomes and RNA polymerase is preserved in evolution, the phenomena of backtracking-driven genome instability for E.coli could occur in other organisms as well. It may potentially explain, for example, some cases of chromosomal fragility associated with certain human diseases” said Dr. Nudler.

New bionic leg – powered knee and ankle joints provide natural gait

Professor Michael Goldfarb, right, with amputee Craig Hutto who is wearing the new bionic leg developed at Vanderbilt. Credit: John Russell, Vanderbilt University

A new lower-limb prosthetic developed at Vanderbilt University allows amputees to walk without the leg-dragging gait characteristic of conventional artificial legs.

The device uses the latest advances in computer, sensor, electric motor and battery technology to give it bionic capabilities: It is the first prosthetic with powered knee and ankle joints that operate in unison. It comes equipped with sensors that monitor its user’s motion. It has microprocessors programmed to use this data to predict what the person is trying to do and operate the device in ways that facilitate these movements.

“When it’s working, it’s totally different from my current prosthetic,” said Craig Hutto, the 23-year-old amputee who has been testing the leg for several years. “A passive leg is always a step behind me. The Vanderbilt leg is only a split-second behind.”

The bionic leg is the result of a seven-year research effort at the Vanderbilt Center for Intelligent Mechatronics, directed by Michael Goldfarb, the H. Fort Flowers Professor of Mechanical Engineering. The project was initially funded by a seed grant from the National Science Foundation, followed by a development grant from the National Institutes of Health. Key aspects of the design have been patented by the university, which has granted exclusive rights to develop the prosthesis to Freedom Innovations, a leading developer and manufacturer of lower limb prosthetic devices.

“With our latest model, we have validated our hypothesis that the right technology was available to make a lower-limb prosthetic with powered knee and ankle joints,” said Goldfarb. “Our device illustrates the progress we are making at integrating man and machine.”

The Vanderbilt prosthesis is designed for daily life. It makes it substantially easier for an amputee to walk, sit, stand, and go up and down stairs and ramps. Studies have shown that users equipped with the device naturally walk 25 percent faster on level surfaces than when they use passive lower-limb prosthetics. That is because it takes users 30 to 40 percent less of their own energy to operate.

“Going up and down slopes is one of the hardest things to do with a conventional leg,” said Hutto. “So I have to be conscious of where I go because I can get very tired walking up and down slopes. But that won’t be a problem with the powered leg because it goes up and down slopes almost like a natural leg.”

Recent technological advances have allowed the Vanderbilt engineers to produce a device that weighs about nine pounds – less than most human lower legs – and can operate for three days of normal activity, or 13 to 14 kilometers of continuous walking, on a single charge. They have also dramatically reduced the amount of noise that the latest model makes, although it is slightly louder than they would like.

One of the latest capabilities that the engineers have added is an anti-stumble routine. If the leg senses that its user is starting to stumble, it will lift up the leg to clear any obstruction and plant the foot on the floor.

In order to incorporate all the improvements, the prosthetic’s hardware design has gone through seven versions and its electronics board has been redone 15 times.

According to Goldfarb, it was tough to make the prosthetic light and quiet enough. In particular, it was difficult to fit the powerful motors and drive train that they needed into the volume available. The biggest technical challenge, however, was to develop the control system.

“As you add greater capability, you are also adding greater liability,” he said. “Not only does the controller have to perform individual operations reliability, but it has to perform several operations at the same time and not get confused.”

The Center for Intelligent Mechatronics is also developing an anthropomorphic prosthetic arm project and an advanced exoskeleton to aid in physical therapy.