Dec 29, 2012

The Sceptical Award

The past years I've been giving away an Sceptical Award to someone(s) who has been working in the scientific or sceptical era and this year I was asking the readers of A Magical Journey if they could suggest anything but you didn't! This means that I had to deside for myself again!

This years winner is last years runner up is Arab Atheists!
They have been inspired by swedish sceptics and been recieving death threaths but survived and they deserve all the support they can get! All atheists and sceptics are all behind you! you are safe with us!

Danny Boston from A Magical Journey

Dec 28, 2012

Cave Dwelling Nettle Discovered in China

South West China, Myanmar and Northern Vietnam contain one of the oldest exposed outcrops of limestone in the world. Within this area are thousands of caves and gorges. It is only recently that botanists have sought to explore the caves for plants. This exploration is yielding many new species new to science, that are known only from these habitats.

The current study was published in the open access journal PhytoKeys.

Kew botanist and nettle expert Alex Monro says, "When my Chinese colleague Wei Yi-Gang from the Guangxi Institute of Botany first mentioned cave-dwelling plants to me, I thought that he was mis-translating a Chinese word into English. When we stepped into our first cave, Yangzi cave, I was spell-bound. It had an eerie moonscape look to it and all I could see were clumps of plants in the nettle family growing in very dark condition."

The plants do not grow in complete darkness but do grow in extremely low light levels, deep within the entrance caverns of the caves (sometimes, in as little as 0.04% full sunlight). The British and Chinese authors have been collecting plants from the Nettle family in this limestone landscape for several years and have just published a paper describing three new species, one from a cave and another two from deep gorges.

The cave-dwelling nettle species in question, was found growing in two caves in the Guangxi province of China. Of the species discovered in gorges, one is known from an unusual and striking rock mineral formation called petaloid travertine. Petaloid travertine is a form of limestone deposited by mineral springs that over time forms large petals of rock, in this case clinging to the vertical walls of a gorge.

Read more at Science Daily

Oldest Known Depiction of Pharaoh Found

The oldest known representation of a pharaoh has been found carved on rocks at a desert site in southern Egypt, according to new research into long forgotten engravings.

Found on vertical rocks at Nag el-Hamdulab, four miles north of the Aswan Dam, the images depict a pharaoh riding boats with attendant prisoners and animals in what is thought to be a tax-collecting tour.

"We don't know with certainty who the king represented at Hamdulab is. We can guess on paleographic and iconographic grounds," Maria Carmela Gatto, associate research scholar in Egyptology at Yale University and co-director of  thee Aswan-Kom Ombo archaeological project in Egypt, told Discovery News.

Indeed, the style of the carvings suggests that the images were made at a late Dynasty date, around 3200-3100 B.C. This would have been the reign of Narmer, the first king to unify northern and southern Egypt, thus regarded by many scholars as Egypt's founding pharaoh.

Dating back more than 5,000 years, the rock drawings appear to feature the earliest known depiction of a pharaoh, according to Gatto and colleagues.

"There are depictions of local rulers since the first half of the fourth millennium B.C., but Hamdulab seems by date to be the earliest datable representation of a king wearing one of the recognizable crowns of the ruler of all Egypt, engaged in a labeled royal ritual," John Darnell, professor of Egyptology at Yale University, told Discovery News.

 Discovered in the 1890s by the archaeologist Archibald Sayce, the carvings remained unnoticed for over a century. In the 1960s, Egyptian archaeologist Labib Habachi photographed Sayce's drawings of the rock images, but never published them.

When one of Habachi's pictures resurfaced in 2008, Gatto investigated the site, discovering an entire rock art gallery.

"Sayce's imperfect hand copy did not concern a single rock art scene, but was rather an excerpt from one of a number of scenes located at short distances from each other," Gatto, Darnell and Belgian archaeologist Stan Hendrickx, wrote in December's issue of the journal Antiquity.

The researchers investigated a total of seven carvings, which feature scenes depicting hunting, warfare, and nautical festival events.

The most extensive rock art picture, nearly 10 feet wide, shows five boats, one of which carries an anonymous king holding a long sceptre and wearing the White Crown, a conical shaped headpiece that symbolized rulership of southern Egypt.

The king is followed by a fan-bearer and preceded by a dog and two standard-bearers. A falcon standard appears below the king, while three of the boats boast a standard with bull horns.

"Both the falcon and the bull are royal symbols, emphasizing the royal character of the boats," the researchers wrote.

At the bottom of the tableau, another boat features a decorated vaulted cabin, which according to the researchers represents a shrine. The vessel is then transformed into a "divine boat," placing the tableaux in a religious context.

In front of the royal boat are four bearded persons holding a rope, likely representing people towing the ship.

"The entire scene depicts the moment that the religious procession of pre-Dynastic Egypt became the triumphant tour of a tax-collecting monarch," the researchers said.

A four-sign hieroglyphic inscription labeled the imagery as a "nautical following."

According to Gatto and colleagues, this is likely related to a royal and ritual event known as the "Following of Horus"-- a biennial tax-collection tour of the king and his court to demonstrate royal authority throughout the land.

Read more at Discovery News

Genesis II: Extraterrestrial Oceans Could Host Life

NASA's battle cry behind the small armada of orbiters, landers and rovers dispatched to Mars is "follow the water!" Where there's water, there could be life, which needs a solvent like water to assemble the complex macromolecules needed for living systems.

Mars is covered with geological evidence that it was once a soggy planet. But no longer. One of the most exciting findings to date from the roving field geologist, the Mars Science Laboratory Curiosity, was the detection of a dried up ancient stream where water once flowed billions of years ago.

The irony is that if you travel a couple hundred million miles beyond Mars' orbit you cross the solar system's frost line, the boundary beyond which there is plenty of water preserved from the planets' birth.

At least six outer moons have subsurface oceans that could potentially be cozy places for life: Europa, Ganymede, Callisto, Titan, Enceladus and Triton. Each of them could have as much if not more water than found in all of Earth’s oceans. In fact Earth is a comparatively dry world.

The idea of a stellar habitable zone, where water can remain stable on a planet's surface, was scientifically spelled out and popularized by Michael Hart in the late 1970s. Since such a zone is a narrow slice of the solar system's real estate, Hart used his widely cited research paper to support the Rare Earth hypothesis: that the evolution of complex life would be hard to replicate in the cosmos.

Today, the concept of a habitable zone is old fashioned says Ken Hand of NASA’s Jet Propulsion Laboratory. "The Goldilocks scenario is outdated. There are new ways to mediate habitability via tidal interactions."

This new paradigm is further bolstered by the emerging realization that there is a tremendous diversity of life on Earth in extreme environments. In fact, the so-called "exteremeophiles" were probably the first inhabitants of Earth -- and will be the last survivors 1 billion years from now.

Finding samples of life in extraterrestrial oceans is no small task. It requires burrowing through miles of a thick ice shell. But in actuality that would be far less difficult than sending an industrial drilling rig and astronaut crew to Mars to penetrate deep into subsurface aquifers.

More importantly, finding life in a Europa ocean would unequivocally prove that a Genesis II took place in the solar system. And that would mean that life is an inevitable spinoff of an evolving universe.

Even more profoundly, if Europan microbes incorporated RNA and DNA into their biological machinery it would demonstrate that the concept of convergent evolution beats out contingent evolution that favors a purely random sequence of events (as in the Rare Earth hypothesis).

Convergent evolution predicts that the universe defaults to the same molecular template for life regardless of the initial starting conditions and biological constraints. No doubt creationists would embrace such news as evidence for intelligent design.

Why can't finding Mars microbes lead us to the same solution? The problem is that if Martians were found to use DNA and RNA, it would be tempting to think that they are really our cousins. The early solar system may have seen planetary cross-fertilization via dispersal of hitchhiking microbes between Earth and Mars meteorites. Or, less likely, Mars may have been contaminated by poorly sterilized spacecraft from Earth.

This would not be the case for any of the outer solar system oceans that have been encapsulated for billions of years.

The Saturnian moon Enceladus is one of the most promising places to go "microbe fishing" though it is a staggering one billion miles away. The Enceladus ocean "jumped out at us," says Hand. Geyser-like plumes spewing off the moon from slush fill surface cracks contain water and organics. The moon is tidally heated and this has been brewing an ocean for billions of years.

At half Enceladus' distance, the Jovian moon Europa seems a better destination for astrobiology hunting. Europa has two to three times more water than Earth. Where Earth's oceans average a depth of a few miles, Europa's ocean is at least ten times deeper.

The European Space Agency's planned Jupiter Icy moons Explorer (JUICE) will tour all three Jovian ocean worlds, Europa, Ganymede and Callisto beginning in 2030. Looking beyond 2030 the mother of all sample returns would be to land on Europa and dispatch a nuclear-heated cryobot probe to melt its way though a thin portion of the ice shell. Ultimately, samples of the Europan ocean would be returned to Earth for study at a class 5 biocontamination lab.

Sterilization would be no problem because the probe would be irradiated in Jupiter’s seething radiation belts. The moon's hydrogen peroxide would further sterilize the probe as it burrowed through the ice.

Read more at Discovery News

Saber Toothed Cats Didn't Starve Into Extinction

The fearsome felines of the Ice Age in California don’t show signs of starving immediately before their extinction. Teeth of saber-toothed cats and the American lions didn’t have wear marks that would have suggested the cats were gnawing on bones in hunger near the time of the cats’ extinctions.

"Tooth wear patterns suggest that these cats were not desperately consuming entire carcasses, as was expected, and instead seemed to be living the 'good life' during the late Pleistocene, at least up until the very end," said lead author Larisa DeSantis of Vanderbilt University in a press release.

Tooth wear patterns did reveal previously unknown differences in the two cat species behavior. Saber-toothed cats, also known as Smilodon, appeared to have regularly crunched bones, and showed no increase in this dietary distinction toward the end of their reign, which spanned from 30,000 to 10,000 years ago. American lions however, were more finicky and seem to have avoided bones, much as modern cheetahs do.

The extinction of the predators remains a mystery. Some have suggested that the changing climate at the end of the last Ice Age along with an influx of animals from Asia, including the ferocious Homo sapiens, may have left Smilodon with nothing to grin about.

From Discovery News

Dec 27, 2012

Two New Species of Orchid Found in Cuba

Researchers from the University of Vigo, in collaboration with the Environmental Services Unit at the Alejandro de Humboldt National Park (Cuba), have discovered two new species of Caribbean orchid.

The Caribbean islands have been natural laboratories and a source of inspiration for biologists for over two centuries now. Suffice to say that the studies by Charles Darwin and Alfred Russel Wallace in the tropical archipelagos contributed to the emergence of the theory of evolution.

In this case, a Spanish research team from the University of Vigo has discovered two new species belonging to the orchid family (Orchidaceae: Laeliinae) in Cuba. They have been called Tetramicra riparia and Encyclia navarroi. The two plants were found in the eastern and western zones of the island respectively.

"The first species described, Encyclia navarroi, is an orchid with considerably large flowers. A year later we discovered the Tetramicra riparia species, with very small flowers. The latter is so named because it grows on the banks of stony streams in the mountains of Baracoa, one of the rainiest and least explored areas in Cuba," as Ángel Vale explained. Vale is a researcher at the University of Vigo and co-author of the studies published by the journals Systematic Botany and Annales Botanici Fennici.

Darwin was very much drawn to the orchid family, and used it to propose certain hypotheses about the importance of the relations between flowers and pollinators for biodiversity. Between 25,000 and 30,000 species of these plants are estimated to exist. However, the mechanisms that explain this amazing variety are only now being discovered.

"We could highlight their extraordinary capacity to interact with different types of pollinators. Contrary to most plants, many orchids do not produce nectar or other substances to compensate insects and birds that visit them," explained the researcher.

Orchids' deceit pollination

Despite this, floral visitors are attracted by orchids' colours and shapes, which enables the plants' sexual reproduction. This is known as deceit pollination.

The University of Vigo Plant Ecology and Evolution research team, which Vale belongs to, is studying the ecological and evolutionary consequences of deceit pollination in orchids that are endemic to the Greater Antilles: Cuba, Jamaica, Hispaniola and Puerto Rico. One of the mysteries they aim to solve is if the deceit orchids have a greater taxonomic and genetic diversity than other nectar-producing species.

Vale and his team are drawing up studies in the Antilles not only to reconstruct the evolutionary history of orchids but also to analyse the effect of pollinators in the reproduction of plants, and how this interaction has modelled the colourful aspect of these Caribbean flowers.

"Despite the fact that T. riparia's flowers have a complete central petal, just like other species that make up a subgenre endemic to Cuba; the way they grow is very similar to a more widespread group that seems to have diverged on the neighbouring island of Hispaniola. Our work provides molecular evidence of the greater relationship of T. riparia with these species on the neighbouring island. This is in consonance with the geological history of the Caribbean islands, according to which the eastern end of Cuba was in close contact with that land," pointed out Vale.

Scientists are currently trying to estimate how many millions of years ago this and other Caribbean species saw the light of day. This will enable them to test whether the ancestor of this species was already in Cuba, or if on the contrary, it evolved from an ancestor that colonised the island from neighbouring archipelagos.

Read more at Science Daily

Study Hints That Stem Cells Prepare for Maturity Much Earlier Than Anticipated

Unlike less versatile muscle or nerve cells, embryonic stem cells are by definition equipped to assume any cellular role. Scientists call this flexibility "pluripotency," meaning that as an organism develops, stem cells must be ready at a moment's notice to activate highly diverse gene expression programs used to turn them into blood, brain, or kidney cells.

Scientists from the lab of Stowers Investigator Ali Shilatifard, Ph.D., report in the December 27, 2012 online issue of Cell that one way cells stay so plastic is by stationing a protein called Ell3 at stretches of DNA known as "enhancers" required to activate a neighboring gene. Their findings suggest that Ell3 parked at the enhancer of a developmentally regulated gene, even one that is silent, primes it for future expression. This finding is significant as many of these same genes are abnormally switched on in cancer.

"We now know that some enhancer misregulation is involved in the pathogenesis of solid and hematological malignances," says Shilatifard. "But a problem in the field has been how to identify inactive or poised enhancer elements. Our discovery that Ell3 interacts with enhancers in ES cells gives us a hand-hold to identify and to study them."

In 2000, Shilatifard identified Ell3 as the third member of the Ell (for "Eleven-nineteen lysine-rich leukemia gene") family of elongation factors, proteins that increase the rate at which genes are expressed. "At the time, we didn't think much of Ell3 because it was highly expressed in testes," says Shilatifard, noting that then people thought that sperm were merely vessels used to carry paternal DNA to an egg and that associated factors would have little relevance to the regulation of future gene expression in the resulting embryo.

But a few years back, a curious Open University graduate student working in the Shilatifard lab, Chengqi Lin, started exploring a potential function for the neglected gene by initiating a global search for regions occupied by Ell3 in the genome of mouse embryonic stem cells. His search in collaboration with a bioinformatician in the Shilatifard lab, Alexander S. Garruss, revealed that Ell3 sits on more than 5,000 enhancers, including many that regulate genes governing stem cell maturation into spinal cord, kidney, and blood cells.

"What was interesting was that Ell3 marked enhancers that are active and inactive, as well as enhancers that are known as "poised," says Lin, referring to a transition state from inactive to active. "That indicated that Ell3's major function might be to prime activation of genes that are just about to be expressed during development."

The fact that silent genes can be "primed" for expression was no surprise: researchers knew that the enzymatic machine that copies DNA into the RNA blueprint for proteins -- a protein called Pol II -- often pauses at the start of a gene, presumably revving its engine in preparation to jump across the genetic start gate in response to a developmental signal. However, Shilatifard and colleagues showed several years ago that paused Pol II is not a prerequisite for rapid transcriptional induction.

The surprise came when researchers used a molecular trick to deplete mouse ES cells of Ell3 and then did a "genomic" survey. They found that paused Pol II vanished from the start sites of many genes in Ell3-deficient cells. This means that not only does Ell3 preferentially mark stem enhancers, but also that its presence there is necessary to keep an idling Pol II ready for action.

Most of the current study defines how, when the developmental time is right, enhancer-bound Ell3 cooperates with components of a big-boss elongation factor called the Super Elongation Complex to release Pol II from the start gate, allowing the expression of genes required for stem cell differentiation. Critical among those findings is their observation that mouse stem cells depleted of Ell3 failed to activate genes expressed in mature cell types.

These results alone are cause for any lab to start chilling the champagne, yet a surprising coda to the study, leaves readers with yet another revelation. Collaborating with Fengli Guo, Ph.D., head of the Stowers electron microscopy core, the team prepared highly magnified images of mouse sperm and observed that both Ell3 and Pol II were present, in sperm nuclei.

In mammals, gene expression regulated by Pol II, a process known as transcription, does not begin until the formation of a single-celled zygote, that is, well after the union of sperm and egg germ cells. "It is very significant that Ell3 and other factors that regulate transcription are found in sperm," says Lin, the study's first author. Lin is cautious in interpreting this finding, "but it would be very exciting to further investigate whether transcription factors found in sperm could contribute to the decondensation of sperm chromatin or even further gene activation after fertilization by serving as epigenetic markers."

Shilatifard is also cautious as questions remain to be explored, among them whether Ell3 and Pol II actually contact DNA inside sperm or whether similar processes occur in unfertilized eggs and function in this process. Nonetheless, he feels this finding has fundamental implications, not only for development, but also for where he's going next.

Read more at Science Daily

Mathematician's Century-Old Secrets Unlocked

While on his death bed, the brilliant Indian mathematician Srinivasa Ramanujan cryptically wrote down functions he said came to him in dreams, with a hunch about how they behaved. Now 100 years later, researchers say they've proved he was right.

"We've solved the problems from his last mysterious letters. For people who work in this area of math, the problem has been open for 90 years," Emory University mathematician Ken Ono said.

Ramanujan, a self-taught mathematician born in a rural village in South India, spent so much time thinking about math that he flunked out of college in India twice, Ono said.

But he sent mathematicians letters describing his work, and one of the most preeminent ones, English mathematician G. H. Hardy, recognized the Indian boy's genius and invited him to Cambridge University in England to study. While there, Ramanujan published more than 30 papers and was inducted into the Royal Society.

"For a brief window of time, five years, he lit the world of math on fire," Ono told LiveScience.

But the cold weather eventually weakened Ramanujan's health, and when he was dying, he went home to India.

It was on his deathbed in 1920 that he described mysterious functions that mimicked theta functions, or modular forms, in a letter to Hardy. Like trigonometric functions such as sine and cosine, theta functions have a repeating pattern, but the pattern is much more complex and subtle than a simple sine curve. Theta functions are also "super-symmetric," meaning that if a specific type of mathematical function called a Moebius transformation is applied to the functions, they turn into themselves. Because they are so symmetric these theta functions are useful in many types of mathematics and physics, including string theory.

Ramanujan believed that 17 new functions he discovered were "mock modular forms" that looked like theta functions when written out as an infinite sum (their coefficients get large in the same way), but weren't super-symmetric. Ramanujan, a devout Hindu, thought these patterns were revealed to him by the goddess Namagiri.

Ramanujan died before he could prove his hunch. But more than 90 years later, Ono and his team proved that these functions indeed mimicked modular forms, but don't share their defining characteristics, such as super-symmetry.

The expansion of mock modular forms helps physicists compute the entropy, or level of disorder, of black holes.

Read more at Discovery News

Growing Crystals in Microgravity

Japanese researchers have successfully grown helium crystals in a microgravity environment, using acoustic waves, providing an opportunity to study the dynamics of how such crystals form in much shorter time frames than can be done in terrestrial labs, and perhaps shed light on the underlying fundamental physics. Their results appeared earlier this month in the New Journal of Physics.

Airplanes have been used since 1959 to provide a nearly weightless environment -- mimicking the microgravity of space -- in which to train astronauts and conduct research. They have colorful nicknames like "Vomit Comet" or NASA's "Weightless Wonder."

Such an aircraft flies in a long parabolic arc, first climbing, then entering into a dive. By controlling the propulsion and steering, it's possible to cancel out any drag (air resistance), at least for about 25 seconds or so.

In that time, passengers on the craft feel as if they are free-falling in a vacuum -- as close to weightlessness as it is possible to achieve without venturing into space. And various experiments have been performed to study phenomena in this unique environment.

NASA has sponsored research in studying crystal formation in microgravity since the 1970s during the Skylab missions. Crystals are vital components in much of modern technology, including microchips, video cameras, radiation detectors, digital watches, and semiconductors.

But in order to be used in many of these applications, the crystals can't have too many defects. A better understanding of the processes by which they form would enable scientists to better control those growth conditions. Microgravity environments give scientists control over one important variable, gravity, so they can study how the process is altered under changing circumstances.

The Japanese researchers, from the Tokyo Institute of Technology, used a small jet plane provided by the Japan Aerospace Exploration Agency (JAXA) to perform eight experiments on crystals during a two-hour flight.

They used a common growth process called Ostwald ripening, in which larger crystals continue to grow at the expense of smaller crystals. It often occurs in ice cream, making the frozen treat become crunchier over time.

The TIT team built a special refrigerator for the plane with a windows so they could watch the crystal formation in action. Then they placed large helium crystals in the bottom of a vacuum chamber and increased the pressure. When the crystals were zapped with acoustic waves, they crumbled into tiny pieces.

Normally it takes a long time to form crystals via Ostwald ripening -- unless you have access to a superfluid. The crystal pieces were splashed with a helium-4 superfluid -- a special state of matter with no viscosity, meaning it can flow without friction.

Per the paper's lead author, Ryuji Nomura, "Helium crystals can grow from a superfluid extremely fast because the helium atoms are carried by a swift superflow, so it cannot hinder the crystallization process." The low temperatures and high pressure in a microgravity environment didn't hurt, either.

Read more at Discovery News

Dec 26, 2012

Fluctuating Environment May Have Driven Human Evolution

A series of rapid environmental changes in East Africa roughly 2 million years ago may be responsible for driving human evolution, according to researchers at Penn State and Rutgers University.

"The landscape early humans were inhabiting transitioned rapidly back and forth between a closed woodland and an open grassland about five to six times during a period of 200,000 years," said Clayton Magill, graduate student in geosciences at Penn State. "These changes happened very abruptly, with each transition occurring over hundreds to just a few thousand years."

According to Katherine Freeman, professor of geosciences, Penn State, the current leading hypothesis suggests that evolutionary changes among humans during the period the team investigated were related to a long, steady environmental change or even one big change in climate.

"There is a view this time in Africa was the 'Great Drying,' when the environment slowly dried out over 3 million years," she said. "But our data show that it was not a grand progression towards dry; the environment was highly variable."

According to Magill, many anthropologists believe that variability of experience can trigger cognitive development.

"Early humans went from having trees available to having only grasses available in just 10 to 100 generations, and their diets would have had to change in response," he said. "Changes in food availability, food type, or the way you get food can trigger evolutionary mechanisms to deal with those changes. The result can be increased brain size and cognition, changes in locomotion and even social changes -- how you interact with others in a group. Our data are consistent with these hypotheses. We show that the environment changed dramatically over a short time, and this variability coincides with an important period in our human evolution when the genus Homo was first established and when there was first evidence of tool use."

The researchers -- including Gail Ashley, professor of earth and planetary sciences, Rutgers University -- examined lake sediments from Olduvai Gorge in northern Tanzania. They removed the organic matter that had either washed or was blown into the lake from the surrounding vegetation, microbes and other organisms 2 million years ago from the sediments. In particular, they looked at biomarkers -- fossil molecules from ancient organisms -- from the waxy coating on plant leaves.

"We looked at leaf waxes because they're tough, they survive well in the sediment," said Freeman.

The team used gas chromatography and mass spectrometry to determine the relative abundances of different leaf waxes and the abundance of carbon isotopes for different leaf waxes. The data enabled them to reconstruct the types of vegetation present in the Olduvai Gorge area at very specific time intervals.

The results showed that the environment transitioned rapidly back and forth between a closed woodland and an open grassland.

To find out what caused this rapid transitioning, the researchers used statistical and mathematical models to correlate the changes they saw in the environment with other things that may have been happening at the time, including changes in the Earth's movement and changes in sea-surface temperatures.

"The orbit of the Earth around the sun slowly changes with time," said Freeman. "These changes were tied to the local climate at Olduvai Gorge through changes in the monsoon system in Africa. Slight changes in the amount of sunshine changed the intensity of atmospheric circulation and the supply of water. The rain patterns that drive the plant patterns follow this monsoon circulation. We found a correlation between changes in the environment and planetary movement."

The team also found a correlation between changes in the environment and sea-surface temperature in the tropics.

"We find complementary forcing mechanisms: one is the way Earth orbits, and the other is variation in ocean temperatures surrounding Africa," Freeman said. The researchers recently published their results in the Proceedings of the National Academy of Sciences along with another paper in the same issue that builds on these findings. The second paper shows that rainfall was greater when there were trees around and less when there was a grassland.

"The research points to the importance of water in an arid landscape like Africa," said Magill. "The plants are so intimately tied to the water that if you have water shortages, they usually lead to food insecurity.

Read more at Science daily

Death By Black Hole Firewall Incineration It Shall Be

Black holes are a perennial favorite among physics buffs, who by now have the usual facts about such objects down pat: Most black holes form when stars explode as supernovae; all that matter collapsing into a dense object from which nothing, not even light, can escape, because of the strong gravitational effects. Lurking deep within a black hole is a point that is infinitely small and dense called the singularity.

While nothing can escape a black hole once it crosses the event horizon, thanks to a peculiar quirk of the quantum vacuum, it evaporates over time, emitting radiation (Hawking radiation) in the process -- and how long it takes for the black hole to evaporate depends on its size (the bigger it is, the longer it takes to evaporate).

Oh, and if, say, an astronaut happened to accidentally cross the event horizon, he or she would technically be in freefall and thus wouldn't notice anything particularly unusual -- not at first. It's only as said astronaut approached the singularity that gravity would become so extreme, s/he would be "spaghettified."

Except now that might not be the case. There's a hypothesis currently being bandied about by theoretical physicists that, instead, the unfortunate astronaut would encounter a massive wall of fire as s/he tried to cross the event horizon and burn up before s/he got anywhere near the singularity.

Call it the 'Paradox of the Firewall.'

It started earlier this year at the Kavli Institute of Theoretical Physics in Santa Barbara, where string theorist Joe Polchinski is permanently ensconced. He'd been puzzling over a nagging suspicion that something wasn't quite right with the conventional picture of what happens at the event horizon for years, and was never quite able to put those misgivings to rest.

When Polchinski and a few colleagues started playing around with toy models, essentially running the argument for Hawking radiation in reverse, it brought a few salient issues into sharp focus.

The result was a controversial paper claiming that in order to not have a firewall at the event horizon, physicists would need to sacrifice another one of their cherished assumptions. Per a Simons Science News article (by yours truly):

At the heart of this particular puzzle lies a conflict between three fundamental postulates beloved by many physicists.

The first, based on the equivalence principle of general relativity, leads to the No Drama scenario: Because Alice is in free fall as she crosses the horizon, and there is no difference between free fall and inertial motion, she shouldn’t feel extreme effects of gravity.

The second postulate is unitarity, the assumption, in keeping with a fundamental tenet of quantum mechanics, that information that falls into a black hole is not irretrievably lost.
Lastly, there is what might be best described as “normality,” namely, that physics works as expected far away from a black hole even if it breaks down at some point within the black hole — either at the singularity or at the event horizon.

Want to get rid of the firewall? It'll cost you, per Polchinski et al., and that price is either conceding that information is lost (which should make Stephen Hawking and his collaborator Kip Thorne pretty happy, since they famously embraced this view in the 1990s), or modifying quantum field theory in some significant way.

Naturally, not everyone agrees. That paper spawned a flurry of others, many aimed at countering the controversial assertions, plus a couple of blog posts: one by Polchinski (over at Cosmic Variance) and another by Caltech physicist John Preskill. (There's also this latest take at Quantum Moxie.)

It's a complicated, multi-faceted problem, as the Simons Science News article makes clear, and much of the discussion is highly technical. But it's such an intriguing idea, it's worth sharing even just a few simple details.

Read more at Discovery News

Dec 25, 2012

Gene Variants Affect Pain Susceptibility in Children

At least two common gene variants are linked to "clinically meaningful" differences in pain scores in children after major surgery, reports a study in the January issue of Anesthesia & Analgesia, official journal of the International Anesthesia Research Society (IARS).

"[O]ur study is highly suggestive of a genetic component in pain response among children," concludes the study by Dr Chantal Mamie and colleagues of Geneva University Hospitals, Geneva, Switzerland. But an accompanying editorial question the relevance of this and previous studies of pain-related genes for management of pain in individual patients.

Gene Variants Influence Pain Scores after Surgery …

The study was designed to explore whether several "candidate" gene variants affected pain scores in a group of 168 children undergoing major surgery -- either abdominal or bone and joint operations. The children and their parents were tested for variant forms ("polymorphisms") of six different genes previously reported as having a possible impact on pain.

The genetic results were compared with the children's pain scores, as routinely monitored during the 24-hour recovery period after surgery. During that time, the children had access to patient- (or parent- or nurse-controlled) analgesia with strong opioid (morphine-related) pain relievers.

Variants of two genes were related to "clinically meaningful" increases in pain scores -- at least four "peak" scores higher than six (on a ten-point scale) during the 24 hours after surgery. After adjustment for other factors, the risk of elevated pain scores was 4.5 times higher for children with a specific variant of the gene ABCB1, which affects the transport of opioid drugs to the central nervous system.

Risk of elevated pain scores was 3.5 times higher for children with a certain variant of the gene OPRM, a key target receptor for opioid binding. The associations with ABCB1 and OPRM variants remained significant after adjustment for patterns of gene inheritance from parents. Variants of two additional genes affecting pain perception -- NTRK and COMT -- were linked to more subtle, "subclinical" effects on pain scores.

… But Have No Effect on Use of Pain Medications

Surprisingly -- even though the gene variants affected pain scores -- they were unrelated to the total dosage of opioid medications used. The dosage of patient-controlled analgesia provides an important objective measure of pain and pain control after surgery.

"The present results are plausible given the known functionality of the candidate genes, and are consistent with the findings in adults," Dr Mamie and colleagues write. Although there has been a wealth of research on the genetic basis of pain in adults, the researchers add, "This first but small cohort study provides clues to further explore the genetic foundations of pediatric pain."

In an accompanying editorial, Drs Debra Schwinn and Ruth Landau of University of Washington, Seattle, put the findings in perspective. A decade ago, researchers thought that the discovery of genes affecting pain perception and opioid responses would soon play an important role in "individualizing" pain control after surgery. Subsequent studies have shown that the situation is more complex, and that the inheritance of pain susceptibility and opioid responsiveness is "probably less straightforward and predictable than previously foreseen."

Read more at Science Daily

New Map of Earth's Animals

Alfred Russell Wallace was beaten to the punch in describing evolution by Charles Darwin, but Wallace’s contributions to biology have been just as long-lived. Wallace drew a map of the Earth divided into regions by where animals live. Now, his map is evolving too, with an update including a total of more than 20,000 mammals, birds and amphibians.

"Our study is a long overdue update of one of the most fundamental maps in natural sciences. For the first time since Wallace’s attempt we are finally able to provide a broad description of the natural world based on incredibly detailed information for thousands of vertebrate species,” said co-lead-author, Ben Holt of the University of Copenhagen, in a press release.

The global map data can be used to make regional maps on a smaller scale, not just the planetary scale shown above.The data can even be fed into Google Earth or a Geographic Information System program, the authors noted in the study published in Science Express.

The planetary map was divided into 11 realms, such as Neotropical and Sino-Japanese, and subdivided into 20 "zoogeograghic" regions. The unusual creatures of Madagascar got their own realm. Overall, the map data shows greater biological diversity in the Southern Hemisphere than in the Northern. Currently, only mammals, birds and amphibians are represented. Other classes of animals will be added as the data becomes available.

The new map made use of resources barely imaginable in Wallace’s time. Genetic analysis helped to define species in the modern map along with the classical anatomical descriptions Wallace used. It took 15 researchers and 20 years of data compilation to update Wallace’s original magnum opus of biological geography.

Developing a map of where species live may prove invaluable as a changing global climate, habitat loss and invasive species are rearranging animals’ home ranges.

Read more at Discovery News

Dec 24, 2012

How Excess Holiday Eating Disturbs Your 'Food Clock'

If the sinful excess of holiday eating sends your system into butter-slathered, brandy-soaked overload, you are not alone: People who are jet-lagged, people who work graveyard shifts and plain-old late-night snackers know just how you feel.

All these activities upset the body's "food clock," a collection of interacting genes and molecules known technically as the food-entrainable oscillator, which keeps the human body on a metabolic even keel. A new study by researchers at the University of California, San Francisco (UCSF) is helping to reveal how this clock works on a molecular level.

Published this month in the journal Proceedings of the National Academy of Sciences, the UCSF team has shown that a protein called PKCγ is critical in resetting the food clock if our eating habits change.

The study showed that normal laboratory mice given food only during their regular sleeping hours will adjust their food clock over time and begin to wake up from their slumber, and run around in anticipation of their new mealtime. But mice lacking the PKCγ gene are not able to respond to changes in their meal time -- instead sleeping right through it.

The work has implications for understanding the molecular basis of diabetes, obesity and other metabolic syndromes because a desynchronized food clock may serve as part of the pathology underlying these disorders, said Louis Ptacek, MD, the John C. Coleman Distinguished Professor of Neurology at UCSF and a Howard Hughes Medical Institute Investigator.

It may also help explain why night owls are more likely to be obese than morning larks, Ptacek said.

"Understanding the molecular mechanism of how eating at the "wrong" time of the day desynchronizes the clocks in our body can facilitate the development of better treatments for disorders associated with night-eating syndrome, shift work and jet lag," he added.

Resetting the Food Clock

Look behind the face of a mechanical clock and you will see a dizzying array of cogs, flywheels, reciprocating counterbalances and other moving parts. Biological clocks are equally complex, composed of multiple interacting genes that turn on or off in an orchestrated way to keep time during the day.

In most organisms, biological clockworks are governed by a master clock, referred to as the "circadian oscillator," which keeps track of time and coordinates our biological processes with the rhythm of a 24-hour cycle of day and night.

Life forms as diverse as humans, mice and mustard greens all possess such master clocks. And in the last decade or so, scientists have uncovered many of their inner workings, uncovering many of the genes whose cycles are tied to the clock and discovering how in mammals it is controlled by a tiny spot in the brain known as the "superchiasmatic nucleus."

Scientists also know that in addition to the master clock, our bodies have other clocks operating in parallel throughout the day. One of these is the food clock, which is not tied to one specific spot in the brain but rather multiple sites throughout the body.

The food clock is there to help our bodies make the most of our nutritional intake. It controls genes that help in everything from the absorption of nutrients in our digestive tract to their dispersal through the bloodstream, and it is designed to anticipate our eating patterns. Even before we eat a meal, our bodies begin to turn on some of these genes and turn off others, preparing for the burst of sustenance -- which is why we feel the pangs of hunger just as the lunch hour arrives.

Scientist have known that the food clock can be reset over time if an organism changes its eating patterns, eating to excess or at odd times, since the timing of the food clock is pegged to feeding during the prime foraging and hunting hours in the day. But until now, very little was known about how the food clock works on a genetic level.

What Ptacek and his colleagues discovered is the molecular basis for this phenomenon: the PKCγ protein binds to another molecule called BMAL and stabilizes it, which shifts the clock in time.

Read more at Science Daily

Tau Ceti e: Another Interstellar Target?

Tau Ceti recently crashed into the headlines after it was announced that a system of five worlds may be in orbit around the star. Although the exoplanets have yet to be confirmed, this discovery is profound in that one of the worlds, a "super-Earth" designated Tau Ceti "e" -- may be sitting inside the star's so-called habitable zone.

The habitable zone is considered the perfect location in a star's orbit for a world to support liquid water (it's not too hot and not too cold), a substance essential for the evolution of life as we know it.

If this world is proven to exist -- follow-up studies by other observatories are required to confirm its orbit and size -- the 4.3 Earth-mass world will become famous for being the smallest world discovered within the habitable zone of another star.

Within Reach?

Not only is Tau Ceti's "super-Earth" a curious objective for astronomers to seek out extraterrestrial life, the nearby star could be within the reach of a future interstellar mission.

Tau Ceti may well be in our proverbial "cosmic backyard," but it is still 12 light-years from Earth. The energies and speeds needed to make a hypothetical (unmanned) probe a reality aren't possible using current technologies, but according to Paul Gilster, co-founder of the Tau Zero Foundation and author of the book Centauri Dreams (and writer for the blog of the same name), such a feat may not remain "impossible" for too long.

"Pushing a 'lightsail' by beamed laser or microwave propulsion (leaving the 'fuel' at home) may be able to get us up to ten percent or so of the speed of light, which would give us a mission to Tau Ceti of a bit over a century," Gilster told Discovery News.

"Fusion prospects of the kind studied by Project Icarus (one of the projects managed by the non-profit organization Icarus Interstellar) are also an option, though sails have already been demonstrated in space and are further along in their development."

There's also the possibility of using antimatter to get "maximum bang for the buck," Gilster points out, but we have yet to develop a means of generating enough antimatter for it to be used as an interstellar fuel. And then there's the tricky matter (no pun intended) of storing the stuff and controlling the reactions inside a hypothetical antimatter engine.

But this is the reason why we should be researching multiple avenues of research when it comes to the possible modes of interstellar travel.

"The Tau Zero Foundation hopes to advance the human prospect for interstellar flight by defining the issues and keeping all the propulsion options on the table," Gilster points out. "It is simply too early to down-select to a single propulsion system.

"Instead, incremental advances across the spectrum of possibilities will help us, over time, learn which methods will offer the soundest prospects. We'd like to encourage and, when it becomes possible, assist in the funding of such research.

"A second goal is to keep the idea of interstellar flight in front of the public through education, so that the relevant research is not only highlighted but supported through both philanthropy and government."

Going Interstellar By Public Demand

The selection of propulsion methods is one thing, but interstellar advocates agree that when we do detect that bona fide habitable world -- with hints of a biosphere and presence of liquid water -- the public will demand further study.

And that means physically going there.

"In the event a habitable planet around a nearby star like Tau Ceti is confirmed, the best next step would be a space-based observatory specifically targeting nearby stars (Kepler's targets are much more remote in order to take the statistical pulse of the planet population)," said Gilster. (Targeted searches have been carried out by SETI, in the hope of detecting a radio signal from a hypothetical alien civilization in the Tau Ceti system -- but none have detected any artificial transmissions.)

"I have often imagined the day when scientists directly image an Earth-like extra-solar planet," Icarus Deputy Project Leader Robert Freeland told Discovery News during an interview in October after the discovery of a small exoplanet orbiting Alpha Centauri (a binary star located only 4.4 light-years away). "We would be able to determine the planet's atmosphere and surface temperature from its spectrum, and we would thus know whether it might be able to sustain life as we know it.

"I suspect that once such a discovery hits the news, people worldwide are going to demand that we send a probe to determine whether the planet has life (of any type) and/or could be suitable for human habitation," Freeland added.

"Tau Ceti is about 12 light-years away, and with the right instrumentation, we will be able to make a spectroscopic analysis of the atmospheres of planets there," Gilster said. "If we discover a biosignature indicating life is present, this will clearly make such a planet a priority for any future probes. A probe like this could get into space in the next two decades if funding emerges."

A New Era

By extrapolating the energy we produce today, Gilster is realistic that an interstellar probe may be a long way off. But that's not accounting for unforeseen, disruptive technologies that may rapidly enhance our ability of sending a robotic emissary (and eventually a human mission) to a nearby star.

We are truly in a new era of space exploration. Not only are we discovering a multitude of extra-solar planets, we are also advancing the role that robotics play in space. It's only a matter of time that these machines become so advanced that they will become fully autonomous -- humans will be cut out of the loop. For a robotic interstellar probe, this will be a necessity as the vast interstellar distances will quickly generate unworkable time lags of years to send and receive commands.

The speed of light will quickly become a frustrating barrier (after all, should a probe make it to Tau Ceti, it would take 12 years for us to receive the first images of any "habitable" exoplanet), the probe would be by itself, exploring in the name of humanity.

Read more at Discovery News