Apr 30, 2011

Richard Dawkins and Dr Yan on genetic ancestry


From Bang Goes The Theory

History: Christmas Elements Have Pagan Roots

Roman Ship Emerges Near Ancient Port

A 2,000-year-old Roman ship in the middle of a plain near the ancient port of Rome has been unearthed by Italian archaeologists.

The wooden vessel was found at a depth of 13 feet during repair work on a bridge that links the modern town of Ostia with Fiumicino, where Rome's main airport is located.

Measuring 36 feet in length, the ship is the largest ever excavated near the ruins of Ostia Antica, a port city near the mouth of the Tiber River that rivals the riches of Pompeii.

So far, only the right side of the ship is visible. Remains of ropes, used by the ancient Roman sailors, are beginning to emerge.

“The bow and stern are still missing. From the way the ship is built, we can date it to the first imperial age,” Anna Maria Moretti, archaeological superintendent for Rome and Ostia, said.

A thick layer of clay has basically sealed the vessel, leaving the wood intact.

Described as "spine-tingling" by culture minister Giancarlo Galan, the discovery shows that when the ship sailed the Mediterranean, the coastline was some 2-2.5 miles farther inland than it is now.

Several Roman ships, now housed in a museum at Ostia, were discovered during the construction of the Fiumicino Airport in the 1950s. But experts believe that the newly found ship is much more important.

“It’s a unique find. At that depth, we have never found a ship," Moretti said.

The ship’s large size suggests that it might not be an isolated find. More vessels might be buried in the area, possibly indicating the exact location where the Roman empire's biggest fleet was stationed.

Read more at Discovery News

Apr 29, 2011

China Announces It Will Build Its Own Space Station Within 10 Years

On Monday, China unveiled its plan to build a manned space station in the next decade. This announcement comes from a space program whose development has been, well, skyrocketing; China launched its first astronaut into Earth orbitin 2003 and completed itsfirst spacewalk in 2008. If things go as planned, the station would be the third ever multi-module space station, after Russia’s Mir and the International Space Station.

The space station is currently dubbed Tiangong, meaning “heavenly palace,” but that moniker may not be permanent; China’s space agency is taking suggestions for new names via email.

Designed for a three-person crew, the space station will consist of one core module and two lab units for conducting experiments in astronomy, biology (particularly as it pertains to space radiation), and microgravity.

Weighing in at 60 tons, Tiangong is significantly smaller than its predecessors (the ISS weighs 419 tons; Mir weighed 137).

For the full article head to Discover Magazine

Apr 28, 2011

Why we stick to our own class – it's a meeting of minds

Researchers found that a part of our brain that controls motivation and emotion becomes more active when we meet people "like us".

The findings seem to turn on their head the idea that we are more excited about meeting people above our station and that we aspire to a higher class.

Dr Caroline Zink, at National Institute of Mental Health in Maryland, assessed the socioeconomic status of 23 individuals and then showed them information about someone of relatively higher, lower or similar social standing.

Using a functional magnetic resonance imaging (MRI) scanner they measured the activity in an area of the central brain known as the ventral striatum.

This area is known to be involved in deciding what motivates us and what stirs our emotions.

The researchers found that the closer the person we were looking at was to our own standing, the more area of the brain lit up with activity.

That means the brains of high social status people lit up when meeting other high social class individuals, and lower status individuals' brains lit up when they met others from the same background

The findings in humans are largely consistent with earlier observations in monkeys.

Researchers had shown that monkeys direct their attention to others of higher or lower status depending on their own position in the troop.

"The way we interact with and behave around other people is often determined by their social status relative to our own, and therefore information regarding social status is very valuable to us," said Dr Zink.

However Dr Zink said that as our social status changes, so would the people we associate with.

"As humans, we have the capacity to assess our surroundings and context to determine appropriate feelings and behaviour," Dr Zink said.

Read more at The Telegraph

Stem cell cures under threat from EU court

The academics said that a change in EU law could "wipe out" much of the biotechnology industry and halt work on revolutionary cures for conditions that affect millions of people.

At present Britain is a world leader in the use of stem cells thanks to investment from the private sector and the government.

Scientists are working on treatments for blindness, Alzheimer's, Parkinsons, strokes and spinal injuries as well as coming up with an alternative to testing new drugs on animals.

But scientists say all this work could be halted – and much of it moved to China and the US – if the European Court of Justice makes a new directive effectively outlawing the use of human embryos for any commercial purpose.

EU judges are considering a test case that could make it unlawful to patent applications using embryonic stem cells – or anything derived from them – on moral grounds.

The academics are concerned because the judges have been told that patenting any use of cells derived from human embryos breaches ethical principles.

That recommendation was given by French judge Yves Bot, the "advocate general" appointed to provide reasoned, independent guidance to the court.

He has a powerful voice, and although his opinion is not binding, the court follows his advice in eight out of 10 judgments.

A European legal ban on embryonic stem cell patents will have potentially catastrophic consequences for the multi-billion pound European biotech industry, the UK economy, and patients, according to the scientists.

It will lead to a withdrawal of funding and force patients to go abroad to get treatments initially developed in this country.

It could be potentially damaging to the health and wealth of the nation.

Such is the alarm that thirteen leading researchers have written to the journal Nature outlining their concerns.

They include clone pioneer and "Dolly the Sheep" creator Professor Ian Wilmut, chairman of the Scottish Centre for Regenerative Medicine in Edinburgh, and Professor Austin Smith, director of the Wellcome Trust Centre for Stem Cell Research in Cambridge.

Speaking at a press conference in London, Prof Smith said the advocate general's opinion, issued in a public statement, was "astonishing and shocking".

He said: "If the European Court of Justice was to follow this opinion then the reality ... is that all patents in Europe that involve human embryonic stem cells will be eliminated.

"Other patents will apply in the United States, China and Japan, so this will put Europe at a huge disadvantage. It will effectively wipe out the European biotech industry in this area."

The ruling could potentially have a massive impact on the provision of new treatments, said the scientists.

Read more at The Telegraph

Apr 27, 2011

The brain really can be half asleep, claims research

Researchers discovered that contrary to popular opinion the brain is not always entirely asleep or awake but parts of it can go "offline".

This they claim accounts for the feeling of being "half asleep" which causes forgetfulness and small errors such as misplacing keys or putting the milk in the cupboard or the cereal in the fridge.

The team at the University of Wisconsin, who measured electrical waves in the brain, discovered that some nerve cells in tired yet awake individuals can briefly go "offline".

Professor Chiara Cirelli, a psychiatrist and author of the study, said: "Even before you feel fatigued, there are signs in the brain that you should stop certain activities that may require alertness.

"Specific groups of neurons may be falling asleep, with negative consequences on performance."

Until now, scientists thought that sleep deprivation generally affected the entire brain. Electroencephalograms (EEGs), that measure electrical activity in the brain, show network can detect whether neurons in the brain are on or off.

Prof Cirelli said: "We know that when we are sleepy, we make mistakes, our attention wanders and our vigilance goes down.

"We have seen with EEGs that even while we are awake, we can experience shorts periods of 'micro sleep'."

She said periods of micro sleep were thought to be the most likely cause of people falling asleep at the wheel while driving.

However, the new research found that even before that stage, brains are already showing sleep-like activity that impairs them.

The researchers inserted probes into specific groups of neurons in the brains of freely-behaving rats. After the rats were kept awake for prolonged periods, the probes showed areas of "local sleep" despite the animals' appearance of being awake and active.

Prof Cirelli said: "Even when some neurons went offline, the overall EEG measurements of the brain indicated wakefulness in the rats."

She said there were behavioural problems caused by local sleep episodes.

"When we prolonged the awake period, we saw the rats start to make mistakes," she said.

Read more at The Telegraph

Apr 26, 2011

Cavemen, Cave Bears Battled Over Turf

Cavemen may have had to jostle with bears to settle into caves up to 32,000 years ago, as research shows cave bears lived in the same spaces coveted by prehistoric humans.

The new study on cave bears, which has been accepted for publication in the Journal of Archaeological Science, may also shed light on the age of cave art depicting these enormous animals and why the bears eventually went extinct.

A clue to the mysteries is that from 32,000 to 30,000 years ago, both humans and cave bears lived in two French caves, creating a likely man-versus-bear battle.

"Paleolithic humans used to kill large animals during their hunts, so they were able to kill cave bears," lead author Celine Bon told Discovery News.

While genetics show cave bears consumed a mostly vegetarian diet, "they might have been violent if they were disturbed during hibernation or if they felt frightened," added Bon, a researcher in the Institute of Biology and Technology at Saclay, France.

"In such a case, they may have been very dangerous because of their huge size and their impressive claws and canines (teeth)."

For the study, Bon and her colleagues performed radiocarbon dating, mitochondrial DNA analysis and isotope investigations of cave bear remains from Chauvet-Pont d'Arc and Deux-Ouvertures caves located along the Ardeche River in France. Both caves feature art on the walls, some of which shows cave bears.

The tests revealed that cave bears inhabited the Ardeche region from around 37,000 to 27,400 years ago, with the oldest samples from Chauvet dating to 29,000 years ago. For a while, the bears had few rivals for the caves

That changed when humans first began to use the natural shelters 32,000 to 30,000 years ago. The DNA analysis determined the cave bear population was small and isolated, and that the bears probably died out not long after humans came onto the scene.

"The cave bear population began to decline at the same time that modern humans arrived in Europe," Bon said. "Yet it is unclear if humans are responsible for the cave bear extinction because of competition over space or food resources, or if the extinction of cave bears is due to climatic and/or environmental changes.

"Our data favor both explanations because they show a small cave bear population size in caves occupied by humans."

She thinks it's doubtful the bears and humans ever lived together simultaneously in the caves. Despite the probable competition, there appears to have been a period where the bears occupied the caves during the winter while the humans took over the caves in the summer. There also might have been intervals lasting several years between cave occupations by either group.

Read more at Discovery News

Apr 25, 2011

Poison Key to Early Life

How baby Earth managed to keep hold of its organic matter after the clubbing it took by a Mars-sized object roughly 4.4 billion years ago has long puzzled scientists.

The throttling was so severe scientists believe Earth melted. Splatters that ended up in space eventually came together to form the moon. Lightweight materials, like water and carbon, would have vaporized. How then did the building blocks for life manage to survive?

Scientists think they have found the answer: The organics were locked in stable chains formed from formaldehyde, an ironic finding considering that formaldehyde ended up being poisonous to the very life it may have made possible.

"Formaldehyde is very interesting, very reactive. It can even react with itself and form complex polymers," George Cody, a senior scientist at the Carnegie Institution of Washington, told Discovery News.

Formaldehyde also is plentiful in molecular clouds in space, meaning ample quantities would have been around for incorporation into the solar system's population.

Two chains of evidence support this theory. First, organic solids have been found in meteorites and in comets. A sample from NASA's Stardust comet mission gave Cody and colleagues a sign they were on the right path.

"It was about the most chemically complex material I had ever seen in my life," Cody said.

Scientists then turned to lab work to reproduce the type of organic matter found in carbonaceous chondrites, a type of organic-rich meteorite, from formaldehyde. They found their formaldehyde-synthesized material was similar to what has been found in carbonaceous chondrites and from Comet Wild 2, which was sampled by NASA's Stardust probe.

The experiments also showed the organics would survive temperatures of up to 1,400 Centigrade (2,552 degrees Fahrenheit).

"The formaldehyde forms these little tiny organic balls," Cody said.

Other molecules found in space, such as hydrogen cyanide, also could polymerize with itself, but they fall apart in hot water, Cody added.

"Formaldehyde is almost unique in its tendency to hang out -- and hang on -- as the solar system got hotter and dryer," said Cody.

Also buttressing the team's findings is a related study showing that comets may be much more watery than previously thought.

Read more at Discovery News

Apr 24, 2011

Rumor: LHC Sees Hint of the Higgs Boson

A leaked internal memo from physicists working at the Large Hadron Collider near Geneva reports a whiff of the Higgs boson, the long-sought theoretical particle that could make or break the standard model of particle physics.

The preliminary note, which is still under review, was posted April 21 in an anonymous comment on physicist Peter Woit’s blog, “Not Even Wrong.” Four physicists claim that ATLAS, one of the LHC’s all-purpose particle hunting experiments, caught a Higgs particle decaying into two high-energy photons — but at a much higher rate than the standard model predicts.

“The present result is the first definitive observation of physics beyond the standard model,” the note says. “Exciting new physics, including new particles, may be expected to be found in the very near future.”

The word from CERN, which operates the LHC, is that the leaked note is not an official result, and hasn’t been backed up by the cast of thousands that makes up the rest of the ATLAS collaboration.

“It’s way, way too early to say if there’s anything in it or not,” said CERN spokesman James Gillies. “The vast majority of these notes get knocked down before they ever see the light of day.”

A member of the ATLAS collaboration who wished to remain anonymous noted that unexpected signals show up in the data pretty frequently, and turn out to be due to errors or biases that went uncorrected. The signal is much more likely to be a fluke than anything else.

The mood in the physics blogosphere is mixed between cautious excitement and outright denial.

“It may well turn out to be a false alarm … or it could be the discovery of the century … stay tuned,” wrote a blogger called Jester at R├ęsonaances, a blog that covers particle theory from Paris.

But graduate student Sarah Kavassalis at The Language of Bad Physics counters, “Until there is an official statement from the collaboration, or even one of the co-authors, this is just gossip. Don’t get excited. Seriously.”

This isn’t the first time a Higgs rumor has swept the physics community, either. A possible detection came from the CDF experiment at the Tevatron, a particle accelerator at Fermilab in Illinois, in July 2010. Blogger and physicist Tommaso Dorigo notes that CDF ought to have seen this new signal if it’s really there.

Whether the Higgs is there or not, the paper is real. Physicists with access to the paper say it begins, “It is the purpose of this Note to report the first experimental observation at the Large Hadron Collider (LHC) of the Higgs particle.”

“It’s exciting stuff if it’s true,” Gillies said.

Read more at Wired Science