Silencing brain cells with yellow and blue light

Neuroscientists at the Massachusetts Institute of Technology have developed a powerful new class of tools to reversibly shut down brain activity using different colors of light. When targeted to specific neurons, they could potentially lead to new treatments for abnormal brain activity associated with disorders including chronic pain, epilepsy, brain injury and Parkinson’s disease.

Such disorders could best be treated by silencing, rather than stimulating abnormal brain activity. These new tools, or ‘super silencers,’ exert exquisite control over the timing in which overactive neural circuits are shut down –an effect that is not possible with existing drugs or other conventional therapies.

The National Science Foundation’s division of mathematical sciences supports the research through a grant to the Cognitive Rhythms Collaborative, which is comprised of four research groups in the Boston area focused on questions in neuroscience. The collaborative brings together researchers with expertise ranging from experimental design to mathematical modeling. The research paper, “High-Performance Genetically-Targetable Optical Neural Silencing by Light-Driven Proton Pumps,” appears in the Jan. 7 issue of the journal Nature.

“Silencing different sets of neurons with different colors of light allows us to understand how they work together to implement brain functions,” explains Ed Boyden, senior author of the study. “Using these new tools, we can look at two neural pathways and study how they compute together,” he says.

The tools promise to help researchers understand how to control neural circuits, leading to new understandings and treatments for brain disorders. Boyden, the Benesse Career Development Professor in the MIT Media Lab and an associate member of the McGovern Institute for Brain Research at MIT, calls brain disorders “some of the biggest unmet medical needs in the world.”

Boyden’s ‘super silencers’ derive from two genes found in different natural organisms such as bacteria and fungi. These genes, referred to as Arch and Mac, are light-activated proteins that help the organisms make energy. When Arch and Mac are placed within neurons, researchers can inhibit their activity by shining light on them. Light activates the proteins, which lowers the voltage in the neurons and safely and effectively prevents them from firing. Arch is specifically sensitive to yellow light, while Mac is activated with blue light.

“In this way the brain can be programmed with different colors of light to study and possibly correct the corrupted neural computations that lead to disease,” explains co-author Brian Chow, postdoctoral associate in Boyden’s lab.

“Multicolor silencing dramatically increases the complexity with which you can study neural circuits,” says co-author Xue Han, another postdoctoral researcher in Boyden’s lab. “We will use these tools to parse out the neural mechanisms of cognition.” …

via Silencing brain cells with yellow and blue light.

Scientists reveal Milky Way’s magnetic attraction

An international research project involving the University of Adelaide has revealed that the magnetic field in the centre of the Milky Way is at least 10 times stronger than the rest of the Galaxy.

The evidence is significant because it gives astronomers a lower limit on the magnetic field, an important factor in calculating a whole range of astronomical data.

Researchers from the Max-Planck-Institute for Nuclear Physics, the University of Adelaide, Monash University and the United States have published their findings in Nature this week.

Dr Roland Crocker, the lead author, and Dr David Jones both worked on the project while based at Monash University and the University of Adelaide’s School of Chemistry and Physics. The two physicists are now based at the Max-Planck-Institute for Nuclear Physics in Heidelberg, Germany.

“This research will challenge current thinking among astronomers,” Dr Crocker says. “For the last 30 years there has been considerable uncertainty of the exact value of the magnetic field in the centre of the Milky Way. The strength of this field enters into most calculations in astronomy, since almost all of space is magnetised,” he says.

Dr Jones says the findings will affect diverse fields, from star formation theory to cosmology.

“If our Galactic Centre’s magnetic field is stronger than we thought, this raises additional questions of how it got so strong when fields in the early universe are, in contrast, quite weak. We know now that more than 10% of the Galaxy’s magnetic energy is concentrated in less than 0.1% of its volume, right at its centre,” he says.

Dr Jones completed his PhD at Adelaide, studying the Galactic Centre magnetic field under the supervision of Dr Raymond Protheroe, Associate Professor of Physics at the University of Adelaide, and Dr Crocker, a former postdoctoral researcher at the University.

“The Milky Way just glows in radio waves and in gamma-rays produced by collisions of energetic particles, and is brightest near its centre. Knowing the magnetic field there helps us understand the source of the radio and gamma-rays better,” says Dr Protheroe.

via Scientists reveal Milky Way’s magnetic attraction.

Related from 2007:

The Black Hole in the Center of the Milky Way Is an Accelerator of Gamma Rays
A new theory rejecting the decaying matter theory
Astronomers have found that the supermassive black hole located in the center of the Milky Way generates the mysterious gamma-ray emission detected in the center of our galaxy.

The mobile magnetic fields around the hole produce high-speed collisions that emit the gamma rays.

Extremely powerful gamma rays, with charges in the tens of tera-electronvolts (1 TeV means 1012 eV) have been picked up recently by ground-based gamma-ray observatories.

Some researchers have proposed them as the result of dark matter particles decaying, but not everybody agrees with this explanation.

The new research comes with

//

the idea that the gamma rays are expelled by the most powerful naturally occurring particle accelerator, better than the best atom smashers used by researchers on Earth. The team made calculations based on the particle accelerator scenario, in which protons around the supermassive black hole are constantly hit by the hole’s magnetic fields. These magnetic interactions speed up the protons so much that they are thrown into surrounding gas clouds.

The hole’s magnetic field extends even farther away, so it keeps on  kicking the protons to even increased speeds as they travel outwards. “Some of the protons could reach energies of 1000 TeV this way,” said team member Fulvio Melia of the University of Arizona, in Tucson, US. …

via  softpedia

A negative phys ed teacher can cause a lifetime of inactivity

Humiliation in physical education class as a child can turn people off fitness for good, according to a University of Alberta researcher.

Billy Strean, a professor in the U of A’s Faculty of Physical Education and Recreation, says a negative lifelong attitude towards physical activity can be determined by either a good or a bad experience, based on the personal characteristics of the coach or instructor. For example, negative experiences may come from a teacher who has low energy, is unfair and/or someone who embarrasses students.

During his research, Strean heard from individuals who opened up about negative experiences with coaches and instructors, some from many years ago.

One study participant wrote, “I am a 51-year-old-woman whose childhood experiences with sports, particularly as handled in school, were so negative that even as I write this my hands are sweating and I feel on the verge of tears. I have never experienced the humiliation nor felt the antipathy toward any other aspect of life as I do toward sports.”

Strean hopes to raise awareness of such experiences so those who instruct children in sport will realize they have the ability to create either a fun and playful experience or an experience of humiliation.

Strean has tips for coaches and teachers, including putting attention on fun, connecting with friends and learning, and, until kids enter their teens, minimizing attention on outcomes.

Strean also found study participants had better experiences from minimally organized games such as street hockey, compared to the more organized activities. He suggests adults try not to over-organize sports and allow the children to explore sporting activities on their own, with minimal rules and no scorekeeping.

via A negative phys ed teacher can cause a lifetime of inactivity.

I was very motivated by getting the presidential physical fitness awards in school.

Iraq inquiry: British firms ‘did pretty well’ out of overthrowing Saddam

British companies have benefited from the award of oil contracts in Iraq because of the decision to help to overthrow Saddam Hussein, Gordon Brown’s chief foreign policy adviser told the Chilcot inquiry yesterday.

Simon McDonald said British companies had “done pretty well” in a recent auction of oil rights and that Britain had “privileged access” to the Government of Nouri al-Maliki, the Prime Minister.

“I do think we have privileged access and I do think that they take account of our views in reaching sovereign decisions,” Mr McDonald told the inquiry.

“I think they have also given us credit when making key commercial decisions — so in the recent auction of oil rights British firms did pretty well.” Mr McDonald said Britain was praised in Iraq for helping the country at a crucially important time and that there would be “lasting benefits for that”.

But he revealed that London had not been informed of the Iraqi Army’s operation in March 2008 to remove Shia militias from Basra, which had been controlled by British Forces.

Mr McDonald said the operation, called Charge of the Knights, had delayed plans to reduce the number of British troops in Iraq from 4,000 to 2,500 until the end of 2008.

“[The Iraqi operation] did take us by surprise and we were not happy at the time in our initial reaction,” Mr McDonald told the inquiry.

“But we quickly reflected and concluded that this an example of the Prime Minister of Iraq taking charge of the vital business of Iraq. So we decided, with the Americans, it was in our collective interest to support it.” The inquiry will hear evidence in secret about a “ceasefire” agreed earlier between British military commanders and the militias, which had allowed troops to withdraw to Basra airport.

Mr McDonald said he believed that Britain’s reputation in the Middle East had been enhanced by the invasion of Iraq.

“It is a part of the world that respects a country which is prepared to put its forces where its mouth is,” he said. “Our key strategic relation is with the United States, and what we did in Iraq has helped that relationship.”

Earlier the inquiry heard that Downing Street called the British Ambassador to Iraq almost daily to demand that the country be stabilised after the invasion so that troops could be transferred to Afghanistan.

Sir William Patey, Ambassador to Baghdad in 2005-06, said that for the first time in his career he received instructions directly from the Prime Minister. But he said that there was a “disconnect” between Tony Blair’s politically motivated demands and the situation faced by British Forces fighting an insurgency in Basra and the south of the country.

“The politics here demanded instant results,” he told the inquiry, “[It was] the first time I have ever had instructions as an ambassador directly from the prime minister … to help get a constitution that the Iraqis would vote positively for, the formation of a new government, create the conditions for the withdrawal of British troops. It was quite simple.”

He added: “They were quite reasonable instructions, provided you realised that they weren’t in my gift or solely in the gift of the British Government.

“There was a tension between the desire for instant results and the realities on the ground. What you could achieve in the sort of timescales that London needed for political reasons — there was a disconnect.”

Sir William said that he was horrified by reports of the Iraqi Interior Ministry operating “death squads” to murder rivals and of the discovery of brutal government detention centres.

There was a breakdown of the rule of law, with the police controlled by political militias or criminal gangs. Military action was required to free three British soldiers who had been seized by police in Baghdad and handed over to a militia.

Sir William, who is now Ambassador to Saudi Arabia, said military commanders faced political pressure to “get quick fixes” while also having to create long-term stability for the country.“I don’t think the tensions ever reached breaking point,” he said.

“I understood the frustration. I was quite frank back about the level of ambition and achievement. There was a healthy balance — them pushing for us to achieve more and us explaining the reality.“There was a sense, obviously, if we were able to reduce our presence in Iraq there would be headroom to reinforce our forces in Afghanistan.”

Sir William said that British forces in Basra would have liked more helicopters to deal with the worsening security situation but they had not beenwere not available.

“It would have been nice to have had more helicopters for the military, but, as you have seen elsewhere, you can’t just conjure up helicopters very easily,” he said.

Sir William said in particular he had been under pressure from Downing Street to engage with the radical Shia cleric Moqtada al-Sadr, who was leading an insurgency against international coalition forces.

“There was rarely a day went by when I did not have a phone call from No 10,” he said. “I was encouraged by No 10 to reach out to the Sadrists to give them the message that we felt they had a place in the political system.”

But he acknowledged that his efforts had had only limited success. “Moqtada refused to see me throughout my time there and every Sadrist I did see seemed to lose their job very soon afterwards,” he said.

Vice-Admiral Charles Style, who was the Deputy Chief of Defence Staff (Commitments), told the inquiry that the “tremendous appetite” from Whitehall for detailed information about what was happening on the ground made it difficult to take a long-term strategic view of the situation.

“It was not so much a question of micro-management, but there was an awful lot of inquisitive concern and interest in a great deal of detail in terms of attempting to understand exactly what was going on almost minute by minute,” he said.

General Sir Nick Houghton, who was Chief of Joint Operations, said that from 2006 there was pressure to wind down British force levels in Iraq to concentrate on the new mission in Afghanistan. “We did not have the means to deliver on the objectives [in Afghanistan],” he said.

“The imperative that came out of the military strategy demands of my superior headquarters was to rebalance in order to gain strategic coherence in Afghanistan.”

The inquiry continues.

via Iraq inquiry: British firms ‘did pretty well’ out of overthrowing Saddam – Times Online.

Drugs May Aid Only Severe Depression, Analysis Says

Some widely prescribed drugs for depression provide relief in extreme cases but are no more effective than placebo pills for most patients, according to a new analysis released Tuesday.

The findings could help settle a longstanding debate about antidepressants. While the study does not imply that the drugs are worthless for anyone with moderate to serious depression — many such people do seem to benefit — it does provide one likely explanation for the sharp disagreement among experts about the drugs’ overall effectiveness.

Taken together, previous studies have painted a confusing picture. On one hand, industry-supported trials have generally found that the drugs sharply reduce symptoms. On the other, many studies that were not initially published, or were buried, showed no significant benefits compared with placebos.

The new report, appearing in The Journal of the American Medical Association, reviews data from previous trials on two types of drugs and finds that their effectiveness varies according to the severity of the depression being treated. …

via Drugs May Aid Only Severe Depression, Analysis Says – NYTimes.com.

Is Plato’s map carved onto a stone in Knowth?

A four-feet granite stone basin in the Eastern passage of Knowth may be engraved with a map of the city of Atlantis, as Plato described it. The three concentric circles match the three concentric lakes of Atlantis. A copy of the stone is displayed in the Boyne Valley visitor centre (see photo).

The similarity was noted by Dr. Ulf Erlingsson, who visited Knowth last month. His book Atlantis from a Geographer’s Perspective: Mapping the Fairy Land will be released in Europe September 30 th (16.95). Plato described an inner island 5 stadia in diameter, surrounded by a circular lake 1 stade wide.

Continuing out, there was a circular island and another lake, each 2 stadia wide. Finally there was another island and lake, each 3 stadia wide. A stade equals 100 fathoms, or 200 yards. Dr Erlingsson suggests in his book that the megalithic yard should be used, which translates to a stade of 166 m.

Says Dr. Erlingsson, “The similarity is near-perfect, but only near: One of the 6 shorelines does not match up between the map and the stone basin. I would definitely like to examine the original.” The original stone basin is inaccessible for visitors, inside the grave mound where it has been for over five thousand years—twice as long as the time since Plato wrote about Atlantis.

Even if this might not actually be a map, it is still striking how common concentric circles are on Ireland, not at least at Tara. Tara is associated in myth with a racetrack, and Plato wrote that Atlantis’ city contained a racetrack. But there is no water in Tara, how to explain that? “One might speculate,” says Dr. Erlingsson, “that Tara, too, is a map, a copy, of another place, created by the mythical Thuata de Danaan.”

via Is Plato’s map carved onto a stone in Knowth?.

How Algal Biofuels Lost a Decade in the Race to Replace Oil

From organism to oil

Turning pond scum into oil isn’t easy, but as a hypothetical energy system, it’s elegant. The theory is that algae will produce more burnable fuel on less land than regular crops, perhaps something like a thousand gallons of oil per acre instead of a few dozen from conventional plants. The food-versus-fuel debates that plague biofuels like corn-based ethanol would disappear. Plus, it’s possible the algae could be engineered to make high-energy fuels suitable even for airplanes. It’s these possibilities that sold the Carter administration’s energy officials.

Phycologists, the people who study algae, discovered that under certain circumstances, some algae start cranking out far more oil than normal. Restrict their nutrients, and for some reason they start producing lots of oil. But they also stop growing. If the scientists could keep the algae multiplying and pull the “lipid trigger” anyway, they’d be in fat city. But their understanding of the biology was incomplete, and the task wasn’t easy. It would take some time and effort to know if and when their the process would become cheap enough to compete with crude. …

Another challenge was getting the algae to keep growing without injecting a lot of energy into the system. They installed large open ponds near Roswell, New Mexico, and began trying to produce tiny algae at oil tanker scales. It worked, but there were problems. Again, it would take some time and effort to know if and when everything would work together.

The program did not get time or the money to find out. By the time Bill Clinton took office, funding for the program had dwindled to a trickle, and in 1996, the Department of Energy abandoned the program to focus all its biofuel efforts on ethanol. A dark decade fell upon the field of algal biofuel. There wasn’t even money available to take care of the algal collection that had been so painstakingly created.

In an effort to salvage some of the science, a few hundred strains of algae were sent to the University of Hawaii, but the refuge proved less than ideal. When a National Science Foundation grant ran out in 2004, it became difficult to continue the laborious work of maintaining the collection. The organisms sit in rows of test tubes living and reproducing. Every two months, they have to be transferred, “passaged,” to a new nutrient-rich tube. Random genetic mutations can enter a population and lead to permanent genetic changes. The algae can die.

It’s not exactly clear how it happened, but a review released earlier this year found that more than half the genetic legacy (.pdf) of the program had been lost. Only 23 of the 51 strains that were extensively studied during the program remain alive and extant. The losses to the rest of the algal cultures in the collection have been even worse.

“The really bloody shame is that of those 3,000, there are maybe 100 to 150 strains that remain at the University of Hawaii,” said Al Darzins, who heads up the resurgent algal biofuels research program at the National Renewable Energy Laboratory.

On January 2, 2008, oil hit $100 a barrel for the first time. Despite some ups-and-downs, the price of oil remains substantially higher than it was through much of the 1990s. As a result, more than 50 companies are now at work on some aspect of biofuel production from algae. …

via How Algal Biofuels Lost a Decade in the Race to Replace Oil | Wired Science | Wired.com.

China’s last tiger is eaten + Battle to save tigers intensifies with only 3,200 left on Earth

The man was sentenced to 12 years in jail, local media reported. Kang Wannian, a villager from Mengla, Yunnan Province, met the tiger in February while gathering freshwater clams in a nature reserve near China’s border with Laos. He claimed to have killed it in self-defence.

The only known wild Indochinese tiger in China, photographed in 2007 at the same reserve, has not been seen since Kang’s meal, the Yunnan-based newspaper Life News reported earlier this month.

The paper quoted the provincial Forestry Bureau as saying there was no evidence the tiger was the last one in China.

A local court sentenced Kang to 10 years for killing a rare animal plus two years for illegal possession of firearms, the local web portal Yunnan.cn reported. Prosecutors said Kang did not need a gun to gather clams.

Four villagers who helped Kang dismember the tiger and ate its meat were also sentenced from three to four years for “covering up and concealing criminal gains”, the report said.

The Indochinese tiger is on the brink of extinction, with fewer than 1,000 left in the forests of Laos, Vietnam, Cambodia, Thailand and Myanmar.

via China’s last tiger is eaten – Telegraph.

Related:

Battle to save tigers intensifies with only 3,200 left on Earth

Conservationists say there are just 3,200 tigers left in the world as the future of the species is threatened by poachers, destruction of their habitat and climate change.

The world population of tigers has fallen by 95 per cent in the past century.

The WWF said it intends to intensify pressure to save the Panthera tigris by classifying it as the most at risk on its roster of 10 critically endangered animals.

It hopes to increase patrols and work with politicians to eradicate poaching and thwart illegal trade of tiger skins and body parts.

The wildlife charity also aims to work with governments to encourage more responsible forest management and compensation for farmers whose livestock are killed by tigers to avoid them being hunted.

Diane Walkington, head of species programme for the WWF in Britain, said: “This year has been designated the International Year of Biodiversity by the United Nations and so we have created a list of 10 critically important endangered animals that we believe will need special monitoring over the next 12 months.

“This year will also be the Chinese Year of the Tiger, and so we have put it at the top of our list. It will have special iconic importance. – telegraph

Insanity? Virtual space station auctioned off for $330,000 in real money

Sold: One virtual space station for $330,000 in real money. It may sound insane, but the buyers and sellers here clearly believe there’s gold in the virtual world of Planet Calypso.

The virtual space station was built by The First Planet Company, a part of MindArk, a Swedish online virtual world maker that operates the Project Entropia Universe, which includes Planet Calypso. A player going by the name of Buzz “Erik” Lightyear paid 3.3 million Project Entropia Dollars for the Crystal Palace, a fully functional space station. Project Entropia Dollars can be exchanged for real money at an exchange rate of 10 to 1.

The purchase isn’t without precedent, as noted by Fatfoogoo’s blog. In 2004, David Storey paid $26,500 for a plot of undeveloped land in Project Entropia. And in 2005, Jon Jacobs spent $100,000 on a virtual night club inside Project Entropia. There’s some real investor speculation going on here, backed by real money. We’ve noted that MindArk’s central bank has been officially sanctioned by the government of Sweden.

The 10-year-old Entropia platform has been developed over the past decade at a cost of $40 million. It was launched in 2003. The Planet Calypso world within the universe has been generating a profit since 2004 and has more than 820,000 registered users in 200 countries. The user-to-user transactions within Entropia Universe exceeded $420 million in 2008.

This may be another indicator of the rise of the virtual goods business model, where players play an online game for free but pay for the digital objects inside it. Players can buy and sell goods inside the worlds, giving them a chance to make real money. Hence, Lightyear’s purchase might not look so crazy a few years from now, if the Project Entropia Universe continues to grow. Lightyear, if he so chooses, can operate a business on the space station, which is depicted in the video below …

via Insanity? Virtual space station auctioned off for $330,000 in real money | VentureBeat.

Related

Virtual goods such as weapons or digital bottles of champagne traded in the US could be worth up to $5bn in the next five years, experts predict.

In Asia, sales are already around the $5bn mark and rapidly growing.

For many, virtual goods are one of the hottest trends in technology and are fuelling huge growth in the social gaming sector.

“This is just an exploding part of the gaming business right now, said venture capitalist Jeremy Liew.

“It is the most exciting area in gaming,” he said.

Mr Liew, whose firm Lightspeed Venture Partners has invested $10m in virtual goods companies, said the rapid growth of the sector was unprecedented.

“We have seen companies go from nothing in the last 18-24 months to tens and hundreds of millions of dollars in revenue.” …

Playfish’s Mr Sarris said that is the main reason people are willing to purchase products that do not exist.

“The way we look at it is it’s no different from paying money to go and see a movie or rent a dvd. What you are paying for is the experience and that notion of entertainment.” …

Central to the early growth of this virtual goods revolution have been social networks like Facebook, MySpace and Bebo.

Users of these networks can also pay for virtual goods, such as digital birthday cards, champagne or flowers.

“Increasingly as people’s relationships migrate online, your interactions occur there,” said Lightspeed’s Mr Liew.

“That makes it more natural for those acknowledgements of how important someone is to us to occur there also. Buying something like virtual champagne or a birthday card is telling someone they are important to you.” …

Nova Scotia’s church star map mystery

An attempt to restore a Nova Scotia church has revealed a mysterious arrangement of stars:

Parishioners at one of Canada’s oldest Anglican churches will be puzzled by an enduring enigma when they gaze heavenward this Christmas.

…

The conundrum emerged after the church, built in 1754, burned on Halloween night in 2001 as a result of arson. The parish sought to reconstruct the building’s interior as closely as possible, and it brought in parishioner Margaret Coolen in 2004 to re-create the ceiling over the altar.

But the church didn’t have a complete set of photographs of the original star pattern, so Coolen, hoping the pattern reflected the actual alignment of heavenly bodies in the night sky, sought the help of astronomer David Turner of Saint Mary’s University in Halifax.

That’s when the first mystery emerged.

Turner recognized the constellation Perseus in the photos of the eastern part of the chancel ceiling. But Perseus, seen from Lunenburg, always lies in the northern part of the sky and never due east.

“We looked at them and didn’t recognize any of the star groups,” Coolen explained of the constellations’ positions. “It looked like they might just simply be put up at random, but it didn’t seem like someone would go to that trouble to put just random stars on the ceiling.”

Coolen suggested that Turner instead look at the stars’ alignment around 2,000 years ago — on Christmas Eve in the year of Jesus’ birth.

Then, using software that plots the positions of heavenly bodies throughout history, Turner had a revelation: The chancel ceiling’s pattern indeed reflected quite closely how the night sky would have looked from Lunenburg all those years past, when constellations appeared in somewhat different locations than today.

“I set the scene for sunset, and bingo! I found myself looking at Perseus in the eastern sky,” he said.

via Damn Data ¦ Nova Scotia’s church star map mystery | Cabinet of Wonders.