Boy Trouble

Boys have biological reason to be troublesome

Children with ADHD have less activity in parietal brain areas while performing attention-demanding problem-solving tasks. Credit: UQ
Children with ADHD have less activity in parietal brain areas while performing attention-demanding problem-solving tasks. Credit: UQ

A team of researchers working with UQ's Queensland Brain Institute (QBI) has discovered more compelling evidence that attention-deficit disorder in young boys is substantially attributable to brain development.

UQ neuroscientist, Dr Ross Cunnington said there appeared to be a biological difference in young boys that made them more susceptible to attention deficit hyperactivity disorder, combined type (ADHD-CT).

“ADHD affects about three-to-five per cent of primary school aged children,” Dr Cunnington said.

“It is the most common neurodevelopmental disorder in children and causes significant delay in educational and social development.”

In a study of boys aged eight-to-twelve, Dr Cunnington and a team of scientists from The University of Queensland and research centres in Victoria used functional magnetic resonance imaging (fMRI) to map the brain activity of each of the boys as they performed a mental rotation task.

The study focused on imaging the parietal lobe, a region of the brain known to become active when something distracts a person from performing or completing a given task.

“We're looking at the interaction that occurs in the brain between the pre-frontal and parietal lobes,” Dr Cunnington said.

“Interactions between these brain areas are crucial for maintaining and focusing attention.

“ADHD can be a problem for young boys because it means they don't do well at school, and there are often serious social consequences as well.

“Severe ADHD could at times lead to a young person becoming alienated from their friends and classmates – which can lead to low self-esteem and further disruptive behaviour.

“Overall, there is strengthening evidence that ADHD has a biological cause. It's not all bad parenting.”

The good news for parents is that most cases of ADHD reduce with age and there are already several effective therapeutic treatments which help control the condition's symptoms.

The Cunnington group's research "Right parietal dysfunction in children with attention deficit hyperactivity disorder, combined type: a functional MRI study" was published in a recent edition of Molecular Psychiatry.

Dr Cunnington established his laboratory at The University of Queensland in January 2007, where he is a Principal Research Fellow and works jointly in the School of Psychology and the Queensland Brain Institute.

Source: University of Queensland

More on Ice 9

Harvard physicists have shown that specially treated diamond coatings can keep water frozen at body temperature, a finding that may have applications in future medical implants.

Doctoral student Alexander Wissner-Gross and Efthimios Kaxiras, physics professor and Gordon McKay Professor of Applied Physics, spent a year building and examining computer models that showed that a layer of diamond coated with sodium atoms will keep water frozen up to 108 degrees Fahrenheit.

In ice, water molecules are arranged in a rigid framework that gives the substance its hardness. The process of melting is somewhat like a building falling down: pieces that had been arranged into a rigid structure move and flow against one another, becoming liquid water.

The computer model shows that whenever a water molecule near the diamond-sodium surface starts to fall out of place, the surface stabilizes it and reassembles the crystalline ice structure.

Simulations show that the process works only for layers of ice so thin they’re just a few molecules wide — three nanometers at room temperature and two nanometers at body temperature. A nanometer is a billionth of a meter.

The layer should be thick enough to form a biologically compatible shield over the diamond surface and to make diamond coatings more useful in medical devices, Wissner-Gross said.

The work is not the first showing that water can freeze at high temperatures. Dutch scientists had shown previously that ice can form at room temperature if placed between a tiny tungsten tip and a graphite surface. Kaxiras and Wissner-Gross’s work shows that ice can be maintained over a large area at body temperature and pressure.

Device manufacturers have been considering using diamond coatings in medical implants because of their hardness. Concerns have been raised, however, because the coatings are difficult to get absolutely smooth, abrasion of the tissue surrounding the implant could result, and that diamond might have a higher chance of causing blood clots than other materials.

Wissner-Gross said a two-nanometer layer of ice would just fill the pits in the diamond surface, smoothing it out and discouraging clotting proteins from attaching to the surface.

“It should be just soft enough and water-friendly enough to smooth out diamond’s disadvantages,” Wissner-Gross said.

Wissner-Gross and Kaxiras are planning experiments to confirm the computerized findings in the real world. Wissner-Gross said they expect results within a year.

“We’re reasonably confident we’ll be able to realize the effect experimentally,” Wissner-Gross said.

Wissner-Gross, who has been a doctoral student at Harvard since 2003, said the research grew out of an interest in the physical interaction of nanostructured surfaces with molecules that are biologically relevant, such as water. Diamond films are growing cheaper, Wissner-Gross said, and as their cost declines the array of possible uses of the material grows wider.

“We both had this notion that it would be very interesting to combine theory with respect to diamond surfaces with what’s going on in cryobiology,” Wissner-Gross said. “We were thinking about how we could leverage this long-term trend [of declining prices] to do something interesting in the medical field.”

The work has won Wissner-Gross the 2007 Dan David Prize Scholarship from Tel Aviv University and the 2007 Graduate Student Silver Award from the Materials Research Society.

Wissner-Gross, who expects to graduate in June 2008, said he plans to continue work not only on this project, but on other efforts concerning the physics of surfaces that have novel properties.

Source: Harvard University, by Alvin Powell

Don't Forget: Drink a Beer—Or Two—Daily!

Study in rats suggests long-term, moderate consumption of alcohol improves recall of both visual and emotional stimuli

You may be hard-pressed to recall events after a night of binge drinking, but a new report suggests that low to moderate alcohol consumption may actually enhance memory.

"There are human epidemiological data of others indicating that mild [to] moderate drinking may paradoxically improve cognition in people compared to abstention," says Maggie Kalev, a research fellow in molecular medicine and pathology at the University of Auckland in New Zealand and a co-author of an article in The Journal of Neuroscience describing results of a study she and other researchers performed on rats. "This is similar to a glass of wine protecting against heart disease, however the mechanism is different."

Kalev and Matthew During, a professor of molecular virology, immunology and medical genetics at The Ohio State University College of Medicine and a principal investigator of gene therapy at Auckland, initially set out to study the role of N-methyl-D-aspartic acid (NMDA) receptors in the neuronal processes of normal and diseased animals. (NMDA receptors are critical to memory, because they regulate the strength of synapses (spaces) between nerve cells through which the cells communicate.) But during their research, they discovered that memory was enhanced when one of its subunits, known as NR1, was strengthened in the hippocampus (a central brain region implicated in episodic memory). They then reviewed previous experiments, which had turned up a link between alcohol consumption and NR1 activity.

"We decided to study if beneficial effects of low-dose alcohol drinking already shown by others," Kalev says, "could be mediated through the mechanism of increasing NR1 expression. We thought it was worth pursuing, since ethanol drinking is such a common pattern of human behavior."

The researchers created two strains of transgenic rats, one that had an abundance of NR1 subunits in their hippocampi and one in which it was suppressed. A group of normal rats and those with the suppressed NR1 action were fed a diet consisting of 0, 2.5 or 5 percent ethanol.

According to Kalev, it is hard to relate the alcohol the rats consumed to human quantities, but "based on their blood alcohol levels, the 2.5 percent ethanol diet was equivalent to a level of consumption that does not exceed [the] legal driving limit. This may be approximately one to two drinks per day for some people or two to three for others, depending upon their size, metabolism or genetic background."

The rats stayed on these diets for eight weeks; behavioral testing to assess cognitive function began after four weeks. One test involved novel object recognition, where rats were placed in a cage with two small objects inside multiple times over a two-day period. Then, one object was swapped for a new toy and rats were scored based on how quickly they explored the unfamiliar piece. In a second paradigm, rats were trained to expect a shock when they crossed from a white compartment to a black one inside a cage; a day after training, the rats were put back in the cage to see if they remembered that the black side was dangerous.

Among the normal rats, the animals that consumed moderate amounts of alcohol fared better on both tests compared with the teetotalers. Rats on a heavy alcohol diet did not do well on object recognition (and, in fact, showed signs of neurotoxicity), but they performed better than their normal brethren on the emotional memory task.

"People often drink to 'drown sorrows,'" Kalev says. "Our results suggest that this could actually paradoxically promote traumatic memories and lead to further drinking, contributing to the development of alcoholism."

Doctors learn to control their own brains' pain responses to better treat patients

Doctors learn to control their own brains' pain responses to better treat patients

Physicians apparently learn to “shut off” the portion of their brain that helps them appreciate the pain their patients experience while treating them and instead activate a portion of the brain connected with controlling emotions, according to new research using brain scans at the University of Chicago.

Because doctors sometimes have to inflict pain on their patients as part of the healing process, they also must develop the ability to not be distracted by the suffering, said Jean Decety, Professor in Psychology and Psychiatry at the University and co-author of “Expertise Modulates the Perception of Pain in Others,” published in the Oct. 9 issue of Current Biology and available Thursday at noon on-line.

“They have learned through their training and practice to keep a detached perspective; without such a mechanism, performing their practice could be overwhelming or distressing, and as a consequence impair their ability to be of assistance for their patients” said Decety, who conducted the study with Yawei Cheng of the Institute of Neuroscience, National Yang-Ming University in Taipei, and colleagues there.

Previous research, including work from Decety’s lab, has shown that the neural circuit that registers pain, is activated if a person sees another person in pain. The response in this circuit, which includes the anterior insula, periaqueducal gray and anterior cigulate cortex, is automatic and may reflect a panic response developed evolutionally as a means of avoiding danger.

The research by Decety and the Taiwanese team shows for the first time that people can learn to control that automatic response.

The team performed its research in Taiwan with two groups of evenly matched men and women with a mean age of 35 and similar socio-economic and educational levels-- a group of 14 physicians and 14 people with no experience in acupuncture. They were tested using a functional MRI.

Brain responses were recorded as individuals from the two groups looked at short video-clips in which people were pricked with acupuncture needles in their mouth regions, hands, and feet. They also watched as the patients were touched with Q-tips. The images appeared in random order.

Among the control group, the scan showed that the pain circuit, which comprises somatosensory cortex, anterior insula, periaqueducal gray and anterior cigulate cortex, was activated when members of that group saw someone touch with a needle but not activated when the person was touched with a Q-tip.

Physicians registered no increase in activity in the portion of the brain related to pain, whether they saw an image of someone stuck with a needle or touched with a Q-tip. However, the physicians, unlike the control group, did register an increase in activity in the frontal areas of the brain--the medial and superior prefrontal cortices and the right tempororparietal junction. That is the neural circuit that is related to emotion regulation and cognitive control.

They also asked the two groups to rate the level of pain they felt people were experiencing while being pricked with needles. The control group rated the pain at about 7 points on a 10-point scale, while the physicians said the pain was probably at 3 points on that scale.

Those findings reflected the prediction the scholars had going into the study.

“It would not be adaptive if this automatic sharing mechanism for pain was not modulated by cognitive control. Think, for instance, of the situations that surgeons, dentists, and nurses face in their everyday professional practices. Without some regulatory mechanism, it is very likely that medical practioners would experience personal distress and anxiety that would interfere with their ability to heal,” the researchers write.

For Decety, this new study also casts light on the mechanisms involved in empathy and empathic concern. The former relies on our capacity to share emotions and feelings with others. If there is too much of an overlap between others and self, such an overlap (reflected by similar neural circuits that automatically and unconsciously resonate between self and other) it could lead to personal distress, which is an aversive reaction. Empathic concern necessitates to regulate our implicit sharing mechanism and frees up processing capacity to act for the sake of the other.

Source: University of Chicago

We All Cuhrazay -whether we look it or not...

Schizophrenia candidate genes affect even healthy individuals

Do gene variants that convey risk for schizophrenia affect apparently healthy individuals? Although these genes are present in every human, individuals may have different versions of these genes, called alleles. While many people who possess these “risk alleles” do not end up with schizophrenia, this does not mean they are unaffected by the presence of the risk allele.

In the largest study of its kind to date, scheduled for publication in the October 1st issue of Biological Psychiatry, researchers sought to examine the impact of a few particular genes, known to be associated with a diagnosis of schizophrenia, on a healthy population.

Stefanis and colleagues recruited more than 2000 young men and measured dimensions of their cognitive abilities that tend to be impaired in individuals diagnosed with schizophrenia. The authors also measured schizotypal personality traits, which represent behaviors that are associated with schizophrenia, such as atypical behaviors and beliefs, suspiciousness or paranoia, and discomfort in social situations.

They then genotyped these volunteers in relation to the four most prominent schizophrenia candidate genes: Neuregulin1 (NRG1), Dysbindin (DTNBP1), D-amino-acid oxidase activator (DAOA), and D-amino-acid oxidase (DAAO).

According to Nicholas Stefanis, the lead author on the paper, their study showed “that apparently normal individuals who posses several risk alleles within these susceptibility schizophrenia genes, have indeed minute decrements in cognitive ability such as decreased attentional capacity and worse performance on memory tasks, and alterations in schizotypal beliefs and experiences.” In other words, they found that the healthy individuals who possessed the risk variants within the DNTBP1, NRG1, and DAAO genes exhibited small reductions in their cognitive performance and had atypical experiences that might be associated with schizophrenia.

John H. Krystal, M.D., Editor of Biological Psychiatry and affiliated with both Yale University School of Medicine and the VA Connecticut Healthcare System, notes: “The genetics of schizophrenia is turning out to be a complicated story involving many so-called “risk gene variants” that are actually commonly present in the general population, i.e., people who do not have schizophrenia and will never develop this disorder.

It is striking that these genes all effect the glutamate system in the brain. Glutamate is the main excitatory chemical messenger used by the cerebral cortex. Thus, this paper highlights a role for glutamate in the development of schizophrenia-like symptoms, attention deficits, and memory problems. This genetic information adds to a growing body of evidence that highlights the potential importance of glutamate systems as a target for new medications for the treatment of schizophrenia.”

Dr. Stefanis, explaining the importance of this study, comments that “these findings support the notion that even at the general population level, the genetic liability to psychosis may be expressed as minute and ‘undetected to the naked eye’ alterations in brain information processing capacity and behavior.” Dr. Krystal adds, “Consistent with a growing body of evidence, this study suggests that there may be subtle cognitive impairments that are present when these common risk gene variants are present in the general population.” Clearly, these findings will have an important impact on the future genetic work in this area.

Source: Elsevier

Splitting Water with Sunlight

Hydrogen is one of the most important fuels of the future, and the sun will be one of our most important sources of energy. Why not combine the two to produce hydrogen directly from solar energy without any detours involving electrical current? Why not use a process similar to the photosynthesis used by plants to convert sunlight directly into chemical energy?

Researchers from the German Max Planck Institute have now developed a catalyst that may do just that. As they report in the journal Angewandte Chemie, titanium disilicide splits water into hydrogen and oxygen. And the semiconductor doesn’t just act as a photocatalyst, it also stores the gases produced, which allows an elegant separation of hydrogen and oxygen.

“The generation of hydrogen and oxygen from water by means of semiconductors is an important contribution to the use of solar energy,” explains Martin Demuth (of the Max Planck Institute for Bioinorganic Chemistry in Mülheim an der Ruhr). “Semiconductors suitable for use as photocatalysts have been difficult to obtain, have unfavorable light-absorption characteristics, or decompose during the reaction.”

Demuth and his team have now proposed a class of semiconductors that have not been used for this purpose before: Silicides. For a semiconductor, titanium disilicide (TiSi2) has very unusual optoelectronic properties that are ideal for use in solar technology. In addition, this material absorbs light over a wide range of the solar spectrum, is easily obtained, and is inexpensive.

At the start of the reaction, a slight formation of oxide on the titanium disilicide results in the formation of the requisite catalytically active centers. “Our catalyst splits water with a higher efficiency than most of the other semiconductor systems that also operate using visible light,” says Demuth.

One aspect of this system that is particularly interesting is the simultaneous reversible storage of hydrogen. The storage capacity of titanium disilicide is smaller than the usual storage materials, but it is technically simpler. Most importantly, significantly lower temperatures are sufficient to release the stored hydrogen.

The oxygen is stored as well, but is released under different conditions than the hydrogen. It requires temperatures over 100°C and darkness. “This gives us an elegant method for the easy and clean separation of the gases,” explains Demuth. He and his German, American, and Norwegian partners have founded a company in Lörrach, Germany, for the further development and marketing of the proprietary processes.


Citation: Martin Demuth et al., A Titanium Disilicide Derived Semiconducting Catalyst for Water Splitting under Solar Radiation—Reversible Storage of Oxygen and Hydrogen, Angewandte Chemie International Edition 2007, 46, No. 41, 7770–7774, doi: 10.1002/anie.200701626

Source: Angewandte Chemie

synesthetic birds

Migrating birds may "see" Earth's magnetic field
Wed Sep 26, 2007 1:20am EDT

By Ben Hirschler

LONDON (Reuters) - Migrating birds, it seems, can "see" the Earth's magnetic field which they use as a compass to guide them around the globe.

Specialized neurons in the eye, sensitive to magnetic direction, have been shown for the first time to connect via a specific brain pathway to an area in the forebrain of birds responsible for vision, German researchers said on Wednesday.

Scientists have known for many years, from behavioral experiments, that birds use an internal magnetic compass to navigate on their epic annual journeys. But exactly how the system works has been a mystery.

Now work by Dominik Heyers and colleagues at the University of Oldenburg in Germany has started to unravel the mechanism at a neuroanatomical level -- and it shows the eye is key.

Magnetic sensing molecules in the eye, known as cryptochromes, appear to stimulate photoreceptors depending on the orientation of the magnetic field.

This strongly suggests migratory birds perceive the magnetic field as a visual pattern, the researchers said.

"It's a pity we cannot ask them, but what we imagine is that it is like a shadow or a light spot on the normal vision of the bird," Heyers said in a telephone interview.

The German team, which published their findings in the online Public Library of Science journal PLoS ONE, based their research on laboratory studies of the garden warbler, a highly migratory bird.

Warblers from Germany and Russia were held in captivity and their nerve patterns traced and analyzed to establish the direct functional link between cells in the retina and the Cluster N forebrain region.

Garden warblers, which are estimated to number around 10 million worldwide, breed in northern Europe and spend the winter in Africa.

See-Through Frog

See-Through Frog Bred in Japan

September 28, 2007—For high school students everywhere, this revealing amphibian may be a cut above regular frogs.

That's because the see-through frog does not require dissection to see its organs, blood vessels, and eggs.

Masayuki Sumida, a professor at the Institute for Amphibian Biology at Japan's Hiroshima University, bred the frog to be a humane learning tool.

"You can watch organs of the same frog over its entire life, as you don't have to dissect it," Sumida told the news agency Agence France-Presse. The scientist announced his research last week at an academic meeting.

Dissecting animals for science has sparked controversies worldwide, even prompting some companies to create computer simulations as cruelty-free alternatives.

Researchers bred the sheer creature—a type of Japanese brown frog—for two recessive genes that make it pale.

Though not yet patented, the frog is the first four-legged, see-through animal to be bred by scientists. Some fish species are also clear.

Only 1 in 16 frogs end up see-through, and Sumida's team has not yet figured out how to pass on the transparent trait to offspring.

—Christine Dell'Amore

The Star Sailors

Polynesian voyage
Adzes form the first hard evidence of two-way travel between Hawaii and Tahiti.


Brendan Borrell




An adze from the Cook Islands
Jane Willcock, Anthropology Museum, The University of Queensland
The discovery of an adze fashioned from Hawaiian basalt on a Tuamotu atoll in French Polynesia provides the first material evidence that ancient voyagers made an 8,000-kilometre round trip from the South Pacific to Hawaii and back again.

More than 2,000 years ago, seafarers from Samoa and Tonga ventured eastward to settle on more remote archipelagos in the Pacific Ocean, including the Cook Islands, Tahiti, and the Marquesas Islands, colonizing most of these places by 900 AD. Eventually, the travellers set foot on Hawaii.

Scientists have long thought that these journeys must have been accidental or one-time events, but recent research has hinted that these peoples were capable of greater feats of navigation than previously suspected. Despite this, there has been debate about how much travel and trade took place among these remote islands in eastern Polynesia during the early years of their colonization; did those settlers who made it to Hawaii ever travel back again?

Hawaiian oral histories point to voyages to and from Tahiti, but in the absence of evidence these feats have remained the stuff of legends.

Volcanic origins

Kenneth Collerson and Marshall Weisler at the University of Queensland, Australia realized that one way to test this possibility was to trace the origins of 19 adzes — axe-like tools made from stone that were used for carving canoes and other wooden objects — that had been recovered from coral atolls in the Tuamotus in the late 1930s.



Click here to view a larger image.
U.S. Central Intelligence Agency
Because the adzes are fashioned from basalt — an igneous rock — they must have been transported from one of the many volcanic island chains in the region, possibly even Hawaii. Because the Tuamotus rose from the sea only after 1200 AD, the adzes provide a record of travel from after that time.

Collerson, a geochemist who studies mantle processes, knew that basalts from different types of islands have a distinctive signature in their trace elements and isotope chemistries. So the team took centimetre-wide chunks from the adzes and compared them to a database they had compiled from sites throughout the Pacific.

Although the Society Islands would have been the nearest source for basalt, the team identified adzes from the Marquesas, Pitcairn, and the Austral islands, indicating extensive travel in the region. One adze had been fashioned from hawaiite, specifically from the island of Kaho'olawe. Collerson says that "the only other possible location on the planet where it could have come from is one of the islands in the middle of the Atlantic" — an extremely unlikely prospect. They checked their result twice over two years before finally submitting their paper to Science, where it appears this week1.

Lonely Journey

Collerson and Weisler's study adds to a growing consensus among scientists about the impressive navigational capacities of ancient Polynesians. "They've really shown how wide a spread or distribution this trading network really had," says Patrick Kirch, an archaeologist at the University of California at Berkeley. "The clincher, of course, is the one from Hawaii."

Earlier this year, another group reported on the presence of Polynesian chicken bones in Chile, confirming that these voyagers made it as far as the New World sometime between 700 and 1390 AD.

The adze finding is also welcome evidence to Geoffrey Irwin, an anthropologist at the University of Auckland, who became a major proponent of the theory that Polynesians systematically colonized the Pacific after following the settlement route himself in a sailboat. He points out that a group of anthropologists have also made the 1-month voyage from Tahiti to Hawaii navigating via celestial clues alone2.

The tip of Hawaii's Kaho'olawe Island is today known as Lae o Kealaikahiki, which means 'cape or headland on the way to Tahiti'. Collerson suggests that rock from this cape in particular may have been taken as a memento by travellers commemorating their long and arduous journey.
Top
References

1. Collerson, K. D. & Weisler, M. I. Science 317, 1907-1911 (2007).
2. Finney, B. R. Science 196, 1277-1285 (1977). | ISI |

The Damn Quantum Weirdness

Katharine Sanderson



When does taking one thing away give you more than what you started with? When quantum mechanics gets involved.

Researchers have shown that removing a photon from a laser beam can lead to it containing more photons than it had before1. This result, along with a few other mathematical tricks, is the first practical demonstration of one of the basic principles of quantum physics — the quantum non-commutative effect — and it is leading the way towards controlling light at the quantum level, and to quantum cryptography.

The commutative law states that when you add one object to a group, and then remove an object from that same group, the final number of objects will be the same as what you started with. That works for apples, oranges and other everyday objects. But when applied to photons, the fundamental quantum particles of light, this law doesn't hold.

To describe a property such as the momentum or position of a photon, researchers use basic mathematical operations. The most basic of these are addition and subtraction.

Researchers have shown theoretically that in quantum physics, performing these quantum operations in different orders will lead to different answers. The operations do not commute — adding and subtracting photons will give very different results depending on the order in which they are done.

It's so weird

The Heisenberg uncertainty principle provides a glimpse of this non-commutative quantum strangeness. The principle says that you can't know with certainty both the exact position and the momentum of a particle, because to measure such things you have to nudge the particle, thereby changing its properties. The mathematical expression of this principle has written into it that measuring position and momentum in different orders produces different results.

"You are working at the quantum level," explains Marco Bellini from the National Institute of Applied Optics in Florence, Italy. "If you did it with ping-pong balls it wouldn't work this way," he says.

Bellini and his colleagues have now shown these odd mathematical quirks experimentally. They shone a laser beam through a spinning glass plate, which adds an element of chaos to the ordered, directional laser light to make it behave like ordinary sunlight. The exact number of photons in the beam isn't known, but the mean number of photons in the light can be determined.

Watch it happen

Bellini then used a quantum-state detector to measure the mean number of photons in that beam, and then tinkered with the light. Using techniques that have been demonstrated previously, he first added then subtracted a photon from the beam before measuring the final mean number of photons. He then did the reverse: subtracting then adding a photon.

The mean number of photons in the resulting beam differed in each case. In fact, under some conditions, subtracting a photon actually changed the quantum state of the beam to the extent that the mean number of photons went up.

"It's the most direct demonstration of lack of commutativity that I am aware of," says Robert Boyd, from the Institute of Optics, University of Rochester, New York.

And it's useful

The technique could in principle be used to 'engineer' light in any desired quantum state. "You can start with normal light, and by adding or subtracting photons you can generate any sort of light you want," says Bellini. This would be incredibly useful for encrypting information through quantum means.

"This allows you to produce different quantum states at will," agrees Boyd.

"This experiment is beautiful," he adds. "Maybe it is even of practical importance."

Visit our newsblog to read and post comments about this story.

Top
References

1. Parigi, V. , Zavatta, A. , Kim, M. & Bellini, M. Science 317, 1890-1893 (2007).

Sixty pint beer binge leads to four-week hangover

It may be the longest hangover in the history of binge beer drinking. When a 37-year old man walked into a hospital emergency room in Glasgow, Scotland last October complaining of "wavy" vision and a non-stop headache that had lasted four weeks, doctors were at first stumped, the British journal The Lancet reported Friday.

The unnamed patient "had no history of head injury or loss of consciousness; his past medical record was unremarkable, and he was taking no medications," Zia Carrim and two other physicians from Southern General Hospital said in a case report.

Body temperature and blood pressure were both normal, and a neurological exam scanned negative.

But when an eye specialist was called in, the fog began to clear, at least for the doctors.

The patient, said the ophthalmologist, had swollen optical discs, greatly enlarged blind spots and what eye doctors call "flame haemorrhages," or bleeding nerve fibres.

"We sought a more detailed history" from the patient, noted Zia drly.

That is when the man revealed he had consumed some 60 pints -- roughly 35 litres -- of beer over a four day period, following a domestic crisis.

Severe dehydration caused the alcohol, the doctors guessed, had led to a rare condition called cerebral venous sinus thrombosis (CVST). A scan of the brain's blood vessels confirmed the diagnosis.

CVST -- which can cause seizures, impaired consciousness, loss of vision and neurological damage -- strikes three or four people per million, mainly children, every year in Britain. The cause is generally unknown.

It took more than six months of long-term blood-thinning treatment to restore the man's normal vision -- and to get rid of the headache, the doctors reported.

Dragonflies

(Credit: iStockphoto/Alan Goulet)

Solving A Dragonfly Flight Mystery

Science Daily — Dragonflies adjust their wing motion while hovering to conserve energy, according to a Cornell University study of the insect's flight mechanics. The revelation contradicts previous speculation that the change in wing motion served to enhance vertical lift.

Dragonflies have two pairs of wings, which sometimes move up and down in harmony. At other times the front set of wings flap out of sync with the back set.
The Cornell physicists came to their conclusions after analyzing high speed images of dragonflies in action. The insects have two pairs of wings, which sometimes move up and down in harmony. At other times the front set of wings flap out of sync with the back set.

The physicists found that dragonflies maximized their lift, when accelerating or taking off from a perch, by flapping both sets of wings together. When they hover, however, the rear wings flap at the same rate as the front, but with a different phase (imagine two people clapping at the same speed, but with one person's clap delayed relative to the other).

The physicists' analysis of the out-of-sync motion showed that while it didn't help with lift, it minimized the amount of power they had to expend to stay airborne, allowing them to conserve energy while hovering in place.

The research will be detailed in a forthcoming issue of Physical Review Letters. The authors are Z. Jane Wang and David Russell.

Note: This story has been adapted from a news release issued by American Physical Society.

Who cares what your name is?

Hormone Therapy Boosts Sexual Interest But Not Memory, Study Suggests Science Daily — Hormone therapy in early post-menopause increases sexual interest, but does not improve memory, according to a new study. "Contrary to what we predicted, hormone therapy did not have a positive affect on memory performance in younger mid-life women," said Pauline Maki, associate professor of psychiatry and psychology at the University of Illinois at Chicago, who led the study. "If women want to improve hot flashes and night sweats -- the primary reason most women seek menopausal relief -- and they want to improve their sexual focus and interest, then this may be a formulation for them." Maki and her colleagues enrolled 180 women between the ages of 45 and 55 whose last menstrual cycle was in the past one to three years. The women were randomly assigned to receive either a placebo or a combination of estrogen and progesterone, also known as Prempro, for four months. The study evaluated memory, attention, cognitive function, emotional status, sexuality and sleep. No significant changes in cognitive function were identified in the newly menopausal women taking hormone therapy compared to the placebo group. Although previous smaller studies have suggested that estrogen provides cognitive benefits in recently menopausal women, Maki said that progestin may counteract these positive effects. Women treated with hormone therapy reported a 32 percent increase in sexual thoughts and a 44 percent increase in sexual interest when compared to women taking placebo, according to the researchers. The study also found that women with vasomotor symptoms, such as hot flashes and night sweats, showed a reduction in symptoms and an improvement in overall quality-of-life when taking hormone therapy versus placebo. The study, which is the largest randomized trial to date examining hormone therapy and memory in midlife women, was stopped early due to declining enrollment that coincided with results of the Women's Health Initiative, which found that the associated health risks of the therapy outweighed the benefits. This research is published in the Sept. 25 issue of the journal Neurology. The study was funded by Wyeth Pharmaceuticals. In recently published related research, Maki has found that testosterone decreases verbal memory and neuronal activation in brain areas involved in memory in older men, suggesting possible detrimental effects of testosterone supplementation, particularly with higher doses.

Plasma (physics) - Wikipedia, the free encyclopedia

Plasma (physics) - Wikipedia, the free encyclopedia

In physics and chemistry, a plasma is typically an ionized gas. Plasma is considered to be a distinct state of matter, apart from gases, because of its unique properties. "Ionized" refers to presence of one or more free electrons, which are not bound to an atom or molecule. The free electric charges make the plasma electrically conductive so that it responds strongly to electromagnetic fields.

Plasma typically takes the form of neutral gas-like clouds (e.g. stars) or charged ion beams, but may also include dust and grains (called dusty plasmas).[1] They are typically formed by heating and ionizing a gas, stripping electrons away from atoms, thereby enabling the positive and negative charges to move more freely.
Contents
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* 1 History
* 2 Common plasmas
* 3 Plasma properties and parameters
o 3.1 Definition of a plasma
o 3.2 Ranges of plasma parameters
o 3.3 Degree of ionization
o 3.4 Temperatures
o 3.5 Potentials [This is a link to part of http://en.wikipedia.org/wiki/Plasma_%28physics%29]
o 3.6 Magnetization
o 3.7 Comparison of plasma and gas phases [This is a link to part of http://en.wikipedia.org/wiki/Plasma_%28physics%29]
* 4 Complex plasma phenomena
o 4.1 Filamentation
o 4.2 Shocks or double layers
o 4.3 Electric fields and circuits
o 4.4 Cellular structure
o 4.5 Critical ionization velocity
o 4.6 Ultracold plasma
o 4.7 Non-neutral plasma
o 4.8 Dusty plasma and grain plasma
* 5 Mathematical descriptions [This is a link to part of http://en.wikipedia.org/wiki/Plasma_%28physics%29]
o 5.1 Fluid model
o 5.2 Kinetic model
* 6 Fields of active research
* 7 Footnotes
* 8 See also
* 9 External links

First International Poetry Festival of Paris

1er Festival International de la Poésie à Paris

Synaesthesia

Grapheme-color synaesthesia

Grapheme-color synaesthesia
Medical Research News
Published: Wednesday, 19-Sep-2007
Print - Grapheme-color synaesthesia Printer Friendly Email - Grapheme-color synaesthesia

A psychological phenomenon known as "grapheme-color synaesthesia" describes individuals who experience vivid colors whenever they see, hear, or think of ordinary letters and digits.

A hallmark of synaesthesia is that individuals tend to be idiosyncratic in their experiences, though these experiences are consistent for synaesthetes throughout their lifetime.

But new research appearing in the September issue of Psychological Science, a journal of the Association for Psychological Science, adds to a growing body of evidence suggesting that a particular commonality exists across synaesthetes, who otherwise have very distinctive experiences.

Psychologist Daniel Smilek and his colleagues at the University of Waterloo have found that a relationship exists between how frequently a synaesthete uses a given digit and the brightness of synaesthetic color experiences That is, the more often letters or digits are used in everyday life, the more luminous the synaesthetic colors.

Interestingly, the researchers also found that this relationship is not limited to synaesthetic color experiences. When non-synaesthetes were asked to select a colors to associate with each letter of the alphabet and the digits 0-9, the non-synaesthetes also selected more luminous colors for digits and letters used more frequently.

The relationship between letter and digit frequency, and color luminance was much weaker for non-synaesthetes than synaesthetes, however. Smilek writes "the evidence suggests the possibility that the unusually strong grapheme-color associations made naturally in synaesthesia may more closely reflect normal cognitive processes than previously thought."

http://www.psychologicalscience.org/

Grok this

San Jose Mercury News - UC-Santa Cruz to put novelist Robert Heinlein's archive online

UC-Santa Cruz to put novelist Robert Heinlein's archive online
By Lisa M. Krieger
Mercury News
Article Launched: 09/20/2007 01:33:30 AM PDT

The complete archive of renowned American science-fiction writer Robert Heinlein will be made available online, thanks to an unusual partnership of the University of California-Santa Cruz and the Heinlein Prize Trust.

Heinlein, who lived in Santa Cruz for two decades, was one of the grand masters of science fiction. He became a pop icon in the 1960s with the publication of "Stranger In A Strange Land," one of the most successful science-fiction novels ever published. He died in 1988.

The entire contents of the Robert A. and Virginia Heinlein Archive - housed in the UC-Santa Cruz Library's Special Collections since 1968 - have been scanned in an effort to preserve the contents digitally while making the collection easily available to both academics and the general public. The digitization project was the brainchild of Art Dula, director of the Heinlein Prize Trust.

The first collection released includes 106,000 pages, consisting of Heinlein's complete manuscripts - including files of all his published works, notes, research, early drafts and edits of manuscripts. The documents offer a window into Heinlein's creative process and provide background and context for his work.

Other collections soon to be added to the online archive will feature Robert and Virginia Heinlein's business and personal correspondence, scrapbooks, photo albums, and unpublished works, including communications with Heinlein's editor and agent.

Sustained by the Sun

Scientific American: Sunny Outlook: Can Sunshine Provide All U.S. Electricity?

Large amounts of solar-thermal electric supply may become a reality if steam storage technology works—and new transmission infrastructure is built


In the often cloudless American Southwest, the sun pours more than eight kilowatt-hours* per square meter of its energy onto the landscape. Vast parabolic mirrors in the heart of California's Mojave Desert concentrate this solar energy to heat special oil to around 750 degrees Fahrenheit (400 degrees Celsius). This hot oil transfers its heat to water, vaporizing it, and then that steam turns a turbine to produce electricity. All told, nine such mirror fields, known as concentrating solar power plants, supply 350 megawatts of electricity yearly.

In the face of mounting concern about climate change, alternatives to coal and natural gas combustion such as these never seemed more attractive. And with the bounty of the sun waiting to be captured near fast-growing major centers of electricity consumption—Las Vegas, Los Angeles and Phoenix, among others—interest in such solar thermal technology is on the rise. The first such plant to be built in decades started providing 64 megawatts of electricity to the neon lights of Vegas this summer.

But physicist David Mills, chief scientific officer and founder of Palo Alto, Calif.–based solar-thermal company Ausra, has bigger ideas: concentrating the sun's power to provide all of the electricity needs of the U.S., including a switch to electric cars feeding off the grid. "Within 18 months, with storage, we will not only reduce [the] cost of [solar-thermal] electricity but also satisfy the requirements for a modern society," Mills claims. "Supplying [electricity] 24 hours a day and effectively replacing the function of coal or gas."

The company insists it can do this at a cost of just 10 cents per kilowatt-hour, analogous to the price of electricity from burning natural gas in California if a cost was imposed for the emission of carbon dioxide, the leading greenhouse gas (as the state's Public Utilities Commission is considering).

Ausra will rely on a different type of concentrating solar power plant to deliver on this promise. French physicist Augustin Fresnel showed in the 19th century that a large lens, like the parabolic troughs of the existing solar-thermal plants, can be broken down into smaller sections that deliver the same focus. Applying this, Mills's design—a compact linear Fresnel reflector—allows for greater ground coverage, lower weight and greater durability than precision-shaped parabolic mirrors. "You can drop stones on it and they bounce off," Mills says. "We would be able to build these in Florida in the hurricane zone."

This Fresnel solar thermal plant also eliminates oil, directly heating water to a lower temperature of roughly 535 degrees F (280 degrees C) at a higher pressure, about 50 bars, or 50 times atmospheric pressure. Then, it uses the resultant steam to turn the same low-temperature turbines as those employed in nuclear reactors.

The amount of electricity produced is simply a function of the sun's bounty and the number of mirrors. "We're moving from 80- to 100-megawatt designs to 700 megawatts and above," says John O'Donnell, Ausra's executive vice president.

The key will be proving performance. Thus far, the company has exactly one solar array, hooked to a coal-fired power plant in Australia to provide extra steam that improves its efficiency at burning the dirty rock. At present, the Ausra mirrors produce just an additional 12 megawatts of extra heat, but there are plans to boost that as high as 38 megawatts thermal.

"The issue of the linear Fresnel concept is proof of performance of a large system, not just a prototype system in the field," says Mark Mehos, concentrating solar power program manager at the National Renewable Energy Laboratory (NREL) in Golden, Colo. Ausra and other companies that employ the same technology, such as New York City–based SkyFuel and Solar Power Group in Munich, Germany, "are making large claims," he says, "without testing in the field."

If those claims stand up, however, solar-thermal plants could provide a significant chunk of the Southwest's—and potentially the nation's—electricity. "The maximum you can get into the grid is about 25 percent from solar," including photovoltaics, Mills says. But "once you have storage, it changes from this niche thing to something that could be the big gorilla on the grid equivalent to coal."

Ausra claims to have solved the storage problem without using molten salts or other expensive means of conserving heat. In fact, the company estimates that the price of its electricity will drop to roughly 8¢ per kilowatt hour if it can store heat for 16 hours. "Thermal storage is generally considered to be quite a bit cheaper than electrical storage," says Nate Blair, a senior analyst at NREL. "There isn't a lot of power generation combined with storage systems that can take advantage of that. [Concentrated solar power] has a leg up on storage in the grid or flow batteries or even ultracapacitors."

The system will employ pressure and a steam accumulator to accomplish the trick. "You allow some of the steam to recondense," O'Donnell explains. "It flashes back to steam when you reduce the pressure just by opening the valve to the turbine."

Such long-term steam storage, however, is unproved. "Steam storage is currently feasible at small levels, for example, one hour or so," NREL's Mehos notes. "Due to large volumes and high pressures involved with steam storage, scaling up steam storage to baseload applications is very high risk."

Assuming that their storage system works, Mills and his colleagues calculated in a paper presented today at the Solar Energy Society World Congress in Beijing that such solar-thermal power plants could match the electricity needs of both California and Texas. And, by combining a system that would meet the needs of California and Texas, solar-thermal plants could supply 96 percent of the national electricity demand. "The entire energy use of 2006, the current technology including storage would use a patch of land 92 miles by 92 miles," O'Donnell says. "Ten percent of the [Bureau of Land Management] land in Nevada is enough."

Even adding a transition to electric-powered vehicles did not alter the sunny picture. "You have to generate more electricity," Mills says. But "it doesn't destroy the correlation" between solar output and electricity demand for things like air conditioning.

Such a solar-dominated grid could also tolerate intermittent resources like wind energy, as long as storage systems worked. "A lot of the [winter] heating load correlates with wind [resources]," Mills adds, and the fickle supply of wind generation can be smoothed with hydropower and solar, he argues.

Such a solar solution to the nation's energy needs would require a host of other investments, including high-energy, long-distance, direct current transmission lines from areas like the Southwest or Southeast with fewer clouds to areas like the Northwest and Northeast with too many. "To do it in the East would drive up the cost because the solar resource isn't as good," NREL's Blair says. "Or you could build some kind of massive transmission system to try and get that power up to the East."

But that technology already exists. "There's no new technology on the transmission side, there are megavolt transmission lines around the world today," O'Donnell says. "It is the cost of building electricity transmission compared to the cost and liability of nuclear waste disposal or cost and liability of long-term carbon sequestration."

Ausra hopes to announce several partnerships this fall and has already acquired the land to build one such solar-thermal plant at an undisclosed location in southern California. If its storage system works and proves cost-effective, Ausra might just help usher in a solar revolution. "We have the ability to transition to a zero-carbon electricity future without moving the electricity price around," O'Donnell says. "That hasn't been part of anybody's conventional wisdom."

How to have sex and survive

Researchers have discovered that even the gruesome and brutal lifestyle of the Evarcha culicivora, a blood gorging jumping spider indigenous to East Africa, can’t help but be tempted by that ‘big is beautiful’ mantra no matter what the costs. A study recently published in Ethology found that despite the inherent risk of sexual cannibalism, virgin females were attracted to bigger males when losing their virginity before opting for the safer smaller male as a longer term mate choice.

It is quite common for male spiders to fall victim to female sexual partners once they have mated as the female is more often than not bigger than her mate. In the case of E. culicivora, the gender roles and the size ranges of both sexes are different from the norm and this is important in understanding the evolution of their mate choice behaviour. Large males are more cannibalistic towards smaller females than vice versa.

Consequently, virgin females prefer larger males as mates, in spite of the increased risk of cannibalism, but once the females have mated they change tact and prefer smaller males. In contrast, males make the same choice regardless of whether they are virgins or not and prefer larger females as mates overall.

Dyslexia: the cure?

Having the right timing 'connections' in brain is key to overcoming dyslexia

Using new software developed to investigate how the brains of dyslexic children are organized, University of Washington researchers have found that key areas for language and working memory involved in reading are connected differently in dyslexics than in children who are good readers and spellers.

However, once the children with dyslexia received a three-week instructional program, their patterns of functional brain connectivity normalized and were similar to those of good readers when deciding if sounds went with groups of letters in words.

"Some brain regions are too strongly connected functionally in children with dyslexia when they are deciding which sounds go with which letters," said Todd Richards, a UW neuroimaging scientist and lead author of a study published in the current issue of the Journal of Neurolinguistics. "We had hints in previous studies that the ability to decode novel words improves when a specific brain region in the right hemisphere decreases in activation. This study suggests that the deactivation may result in a disconnection in time from the comparable region in the left hemisphere, which in turn leads to improved reading. Reading requires sequential as well as simultaneous processes."

Richards and co-author Virginia Berninger, a neuropsychologist, said temporal connectivity, or the ability of different parts of the brain to "talk" with each other at the same time or in sequence, is a key in overcoming dyslexia.

Berninger, who directs the UW's Learning Disabilities Center, compared dyslexia to an orchestra playing with an ineffective conductor who does not keep all the musicians playing in synchrony with each other.

"You have all of the correct instruments but, if the conductor is not doing his or her job of coordination, the right instruments are playing at the wrong time," she said. "This all goes away once the conductor finds a way to signal to the musicians to play at the proper times."

The UW researchers used functional Magnetic Resonance Imaging, or fMRI, to explore brain connectivity. This type of imaging typically shows which parts of the brain are activated but does not indicate how they are connected. However, software developed by Richards, a professor of radiology, enabled the researchers to see brain activity in a specific region, the left inferior front gyrus. This region may serve as the "orchestra conductor" for language. The software also provided a look at how this brain area was connected to a similar region in the right hemisphere. The software and the focus on language centers allowed the researchers to collect data that was not related to the children's heartbeat or breathing.

To explore brain connectivity, the researchers worked with 18 dyslexic children (5 girls and 13 boys) and 21 children (8 girls and 13 boys) who were good readers and spellers. All of the children were of normal intelligence and were in the fourth through sixth grades.

The children had to judge whether groups of pink highlighted letters in pairs of nonsense words could or could not represent the same sound. For example, the letters ea and ee in "pleak" and "leeze" could have the same sound but the ea and eu in "pheak" and "peuch" could not. The children's brains were scanned and then those with dyslexia participated in a three-week program that taught the children the code for connecting letters and sounds with an emphasis on timing. Then the children's brains were scanned again.

Following the treatment, the fMRI scans showed that the patterns of temporal connectivity in brains of the dyslexic children had normalized and were similar to those of the good readers and spellers. In particular, the researchers found that connectivity appeared to be normal between the left inferior frontal gyrus and the right inferior frontal gyrus. The left inferior frontal gyrus is believed to control the functional language system, especially for spoken words, while the right inferior frontal gyrus may be involved in controlling the processing of letters in written words. Prior to the treatment these two areas were overconnected and the left inferior frontal gyrus also was overconnected to the middle frontal gyrus, which is involved in working memory that requires temporal coordination.

"These results might mean that after special teaching the children with dyslexia activated letters in written words first and then switched to sounds in spoken words rather than simultaneously activating both letters and sounds," said Richards. "The overconnection between the language conductor and working memory at the same time may be a signal that working memory is overtaxed. When language processing is more efficient after treatment, working memory does not have to work as hard.

"There is this myth that English is an irregular language," added Berninger. "That's not true. We have a set of alternative ways of spelling the same sounds but this is not taught explicitly. The way phonics is often taught over focuses on single letters and not the letter groups that go with sounds as well. Teaching children with dyslexia to read requires a different approach, one that stresses knowledge of spelling-sound relationships with a twist that tweaks the letter and sound processes to get connected in time in the brain."

The researchers caution that the intervention treatment is not a cure for dyslexia. They said it makes children better readers during specialized instruction, but has not been proven over a long period of time, something they hope to do in the future.

"We have shown that gains can maintain for up to two years with behavior measures, but much research is needed before it can be demonstrated that functional brain connectivity can be maintained," said Berninger.

Source: University of Washington

The Chemistry of Immortality

O, how shall summer's honey breath hold out

Against the wreckful siege of battering days,

When rocks impregnable are not so stout,

Nor gates of steel so strong, but Time decays?

O fearful meditation! where, alack,

Shall Time's best jewel from Time's chest lie hid?

Or what strong hand can hold his swift foot back?

Or who his spoil of beauty can forbid?

O, none, unless this miracle have might,

That in black ink my love may still shine bright.
William Shakespeare

Pathway to cell death redefined in landmark study

A new study led by investigators from the University of Pittsburgh School of Medicine demonstrates that the process of necrosis, long thought to be a chaotic, irreversible pathway to cell death, may actually be triggered as part of a regulated response to stress by a powerful protein, SRP-6, that can potentially halt necrosis in its path. Further, the research team realized that this protein might be harnessed to direct some cells -- those in cancerous tumors, for instance -- to die, while saving others, such as degenerating neural cells responsible for Alzheimer’s and Parkinson’s diseases. The work appears on the Sept. 21 cover of the journal Cell.

This remarkable molecular trigger, SRP-6, is a serine protease inhibitor or serpin, and targets the cell’s digestive center, the lysosome. The authors report that the family of intracellular serpins may help cells survive in the face of stressors by protecting against lysosomal injury and its cellular consequences.

“For years, we believed that cell death related to a catastrophic insult such as a stroke or heart attack that deprives tissue of oxygen couldn’t really be treated, so we focused on strategies to prevent further damage by restoring blood flow as quickly as possible with clot busters and surgery,” said Gary A. Silverman, M.D., Ph.D., chief of newborn medicine in the department of pediatrics at the Pitt School of Medicine and the study’s senior author. “But our research indicates that necrosis can be interrupted and possibly repaired, even after the injury process is well underway. This insight has exciting implications for the management of heart disease, stroke and neurological illnesses.”

Representing more than five years of study, the Cell publication is the result of a chance observation made by primary author Cliff J. Luke, Ph.D., assistant professor of pediatrics at Pitt and an investigator at the university-affiliated Magee-Womens Research Institute. Drs. Luke, Silverman and colleagues have been studying how a certain class of proteins called proteases, when uncontrolled, can kill cells. In the process, they discovered that another group of proteins, the serpins, might block, or inhibit, these destructive proteases and protect cells from injury. SRP-6 is among a vast family of pro-survival serpins, which are key regulatory molecules in many complex biologic processes, including blood cell coagulation, inflammation, tumor growth and cell death. Although previous research has shown that bloodstream serpins, including antithrombin and alpha-1 antitrypsin, control protein degradation, little is known about the role of serpins that function within cells, especially in a living organism.

Enter serendipity. When collecting specimens of a microscopic worm called Caenorhabditis elegans in water, rather than in a saline solution as is more common, Dr. Luke noticed that an extraordinarily large number of the animals were dying. “My worm yield was way down,” he said. When he examined the dying worms, he determined that they were genetic “knock-outs” that had been modified to be deficient in SRP-6. The normal worms were just fine.

A frequently studied animal model because of its 1,000-cell structure, transparency and easily visible development, C. elegans is a primitive organism whose complete genetic code has been sequenced and is well known to scientists. The worm typically lives in soil, flourishes in water and exists to eat bacteria and reproduce. The investigators were using a “reverse genetic” approach in which they hoped, by studying the relatively limited intracellular serpin repertoire of C. elegans, they could gain insights that might be applicable to serpin function in higher organisms, including humans.

“Serpin proteins are critical,” said Dr. Silverman, a neonatologist and a senior investigator at the Magee-Womens Research Institute. “For example, we know that in patients who have a certain type of skin cancer, those whose tumors express a lot of intracellular serpins don’t do as well. Now we know that SRP-6 is a crucial pro-survival mechanism that can protect cells from injury, initiate repair after injury, or, if absent, lead to a cascade of cell death.”

With further investigation, it may be possible to use this knowledge to deprive cancer cells of their serpin protectors and target them for death. Alternatively, physicians might be able to boost serpin activity to stop cells from dying – for example, intestinal cells affected by the bacterial infection necrotizing enterocolitis (NEC), a major cause of death and illness in fragile, premature infants.

“We still treat NEC the same way we did 30 years ago, with supportive care, antibiotics and surgery to remove dead portions of intestine,” said Dr. Silverman. “We can’t stop the mucosal lining from dying. But with these worms as models, we can do drug screens to search for compounds that can block necrosis.”

Drs. Silverman, Luke and colleagues have dramatically illustrated the devastating consequences of cellular stress in C. elegans when the crucial protector SRP-6 is missing. A cascade of cell necrosis begins in SRP-6-deficient animals exposed to a number of different stressors, including water, heat and lack of oxygen. In the case of water exposure, the SRP-6 knock-outs move a bit but soon become immobile. Finally, the worms’ organs are violently expelled through their bodily openings, resulting in what the authors refer to as a “grim fate.”

“Animals with normal genetic sequences are fine in water, but the knock-out animals usually die rapidly,” said Dr. Luke, explaining that this observation led him to realize the importance of SRP-6 in protecting the lysosome, an internal cell structure enclosed in its own protective membrane that acts as the cell’s garbage disposal. Powerful enzymes within the lysosome digest old, worn out proteins, carbohydrates, lipids, DNA, RNA, other damaged cell structures and even invading bacteria and viruses. But if the lysosome becomes damaged and leaky, these enzymes can turn against the cell and possibly overcome the serpin defense – useful if the cell is part of a cancerous tumor.

The investigators determined that SRP-6 staves off necrosis by protecting the lysosome membrane from damage caused by the calpain family of cysteine proteases and by neutralizing other cysteine proteases released from injured cellular structures called organelles as they are being digested by the lysosome. As part of their study, Drs. Silverman, Luke and colleagues labeled enzymes within the lysosomes of SRP-6-deficient animals with a fluorescent biomarker to observe how these enzymes reacted after an injury to the critical structure.

“The lysosomes popped, released their contents into the cell and these digestive enzymes began to activate, making the whole animal fluoresce,” said Dr. Silverman. “Again, this experiment showed the importance of SRP-6 in management of the necrosis pathway.”

“There are a lot of diseases associated with cell necrosis, such as stroke, neurodegenerative diseases and NEC, and now we know that the pathway to necrosis is much more systematic than we once thought it was,” said Dr. Luke. “With further study, we may be able to identify targets of intervention to halt the necrotic progression in some of these diseases and possibly even prevent them.”

Source: University of Pittsburgh

Just in case you thought we already knew everything

Dr. Arend Schwab en ir. Jodi Kooijman investigate the behavior of a moving bicycle. Credit: Sam RentmeesterFMAX

Researchers unravel the working of the bicycle


Dr. Arend Schwab en ir. Jodi Kooijman investigate the behavior of a moving bicycle. Credit: Sam Rentmeester/FMAX

For nearly 150 years, scientists have been baffled by the bicycle. How is it possible that a moving bicycle can, all by itself, be so stable?

Researchers of the Delft University of Technology (Netherlands), working with colleagues from Cornell University and the University of Nottingham, UK, believe they have now found the ultimate model of the bicycle. The researchers discuss their findings in the new edition of Delft Outlook, the science magazine of TU Delft.

'Bicycle manufacturers have never been able to say precisely how a bicycle works', explains Dr Arend Schwab of the Faculty of Mechanical, Maritime and Materials Engineering (3mE). 'They have always had to refine their designs purely through experimentation. In our model, they can enter into the computer all of the various factors that influence the stability and handling of their bicycle. The model then calculates how the bicycle will react at specific speeds.' The model has recently been published in the science magazine Proceedings of the Royal Society, Series A.

Because the model has the ability to indicate whether a design will deliver a jittery bicycle, or indeed a stable one for seniors, the bicycle industry is highly interested in the findings. The head of product development at the Dutch bicycle manufacturing company Batavus, Rob van Regenmortel, is following the research being conducted by Arend Schwab and his fellow researcher Jodi Kooijman very closely.

Van Regenmortel: ‘In designing our bicycles, for years we have worked with three parameters: The overall geometry, the distance between the axles and the angle at which the fork points downwards. These choices were once made by all bicycle makers and have been rarely deviated from because the bicycle appeared to work properly. However, with the new model, we soon hope to be able to design bicycles that are much better oriented toward specific target groups.'

Rob Van Regenmortel hopes to collaborate with Arend Schwab and Jodi Kooijman on a follow-up project to study the human control. The ultimate goal of the bicycle research is to study the interaction between bicycle and rider in order to determine the handling quality of the bicycle. 'In this way, we can – in theory – create a customised bicycle for every rider', says van Regenmortel. 'Individuals who have trouble maintaining their balance, for example, would then no longer be restricted to a tricycle.'

Source: Delft University of Technology

And still more, Horatio, than has ever been dreamt in your philosophy

September 18, 2007—This unusual species of flying fox was recently discovered in the Philippines not long after it was deemed not to exist.

Jake Esselstyn, a biologist with the University of Kansas, was among a team of researchers that found the animal, a type of fruit bat, last year while surveying forest life on the island of Mindoro (see Philippines map).

"When we first arrived on Mindoro, a local resident that we hired as a guide described the bat to me in great detail, and he asked me what it was called," Esselstyn said.

"I politely told him that there was no such bat. I was wrong."

Several days into the survey, the scientists accidentally captured a creature in a net that fit the guide's description: a large flying fox with bright orange fur and distinctive white stripes across its brow and jaw.

"Our guide's description of the animal was quite accurate, and I had to apologize for not believing him," Esselstyn said, adding that the animal is now known as the Mindoro stripe-faced fruit bat.

In his own defense, the scientist pointed out that the species' closest known relative lives some 750 miles (1,200 kilometers) away on an island in Indonesia.

"It makes you wonder if there are other related species on islands between [the two]," he said.

"It also makes you realize how there are probably many more species which have yet to be discovered—in the Philippines and elsewhere," Esselstyn added.

"This discovery emphasizes the need for a great deal more basic biodiversity inventory research."

—Blake de Pastino

•

Atlantis revisited

Julian Ryall in Tokyo
for National Geographic News
September 19, 2007


Submerged stone structures lying just below the waters off Yonaguni Jima are actually the ruins of a Japanese Atlantis—an ancient city sunk by an earthquake about 2,000 years ago.

That's the belief of Masaaki Kimura, a marine geologist at the University of the Ryukyus in Japan who has been diving at the site to measure and map its formations for more than 15 years.

Each time he returns to the dive boat, Kimura said, he is more convinced than ever that below him rest the remains of a 5,000-year-old city.

"The largest structure looks like a complicated, monolithic, stepped pyramid that rises from a depth of 25 meters [82 feet]," said Kimura, who presented his latest theories about the site at a scientific conference in June.

But like other stories of sunken cities, Kimura's claims have attracted controversy.

"I'm not convinced that any of the major features or structures are manmade steps or terraces, but that they're all natural," said Robert Schoch, a professor of science and mathematics at Boston University who has dived at the site.

"It's basic geology and classic stratigraphy for sandstones, which tend to break along planes and give you these very straight edges, particularly in an area with lots of faults and tectonic activity."

And neither the Japanese government's Agency for Cultural Affairs nor the government of Okinawa Prefecture recognize the remains off Yonaguni as an important cultural property, said agency spokesperson Emiko Ishida.

Neither of the government groups has carried out research or preservation work on the sites, she added, instead leaving any such efforts to professors and other interested individuals.

Ruins Point

Yonaguni Jima is an island that lies near the southern tip of Japan's Ryukyu archipelago, about 75 miles (120 kilometers) off the eastern coast of Taiwan (see map).

A local diver first noticed the Yonaguni formations in 1986, after which a promontory on the island was unofficially renamed Iseki Hanto, or Ruins Point.

The district of Yonaguni officially owns the formations, and tourists and researchers can freely dive at the site.

Some experts believe that the structures could be all that's left of Mu, a fabled Pacific civilization rumored to have vanished beneath the waves.

On hearing about the find, Kimura said, his initial impression was that the formations could be natural. But he changed his mind after his first dive.

"I think it's very difficult to explain away their origin as being purely natural, because of the vast amount of evidence of man's influence on the structures," he said.

(Related: "Pyramid in Bosnia—Huge Hoax or Colossal Find?" [May 12, 2006].)

For example, Kimura said, he has identified quarry marks in the stone, rudimentary characters etched onto carved faces, and rocks sculpted into the likenesses of animals.

"The characters and animal monuments in the water, which I have been able to partially recover in my laboratory, suggest the culture comes from the Asian continent," he said.

"One example I have described as an underwater sphinx resembles a Chinese or ancient Okinawan king."

(See pictures of the "Japanese Atlantis" formations.)

Whoever created the city, most of it apparently sank in one of the huge seismic events that this part of the Pacific Rim is famous for, Kimura said.

The world's largest recorded tsunami struck Yonaguni Jima in April 1771 with an estimated height of more than 131 feet (40 meters), he noted, so such a fate might also have befallen the ancient civilization.

Kimura said he has identified ten structures off Yonaguni and a further five related structures off the main island of Okinawa. In total the ruins cover an area spanning 984 feet by 492 feet (300 meters by 150 meters).

The structures include the ruins of a castle, a triumphal arch, five temples, and at least one large stadium, all of which are connected by roads and water channels and are partly shielded by what could be huge retaining walls.

Kimura believes the ruins date back to at least 5,000 years, based on the dates of stalactites found inside underwater caves that he says sank with the city.

And structures similar to the ruins sitting on the nearby coast have yielded charcoal dated to 1,600 years ago—a possible indication of ancient human inhabitants, Kimura added.

But more direct evidence of human involvement with the site has been harder to come by.

"Pottery and wood do not last on the bottom of the ocean, but we are interested in further research on a relief at the site that is apparently painted and resembles a cow," Kimura said.

"We want to determine the makeup of the paint. I would also like to carry out subsurface research."

Natural Forces

Toru Ouchi, an associate professor of seismology at Kobe University, supports Kimura's hypothesis.

Ouchi said that he has never seen tectonic activity having such an effect on a landscape either above or below the water.

"I've dived there as well and touched the pyramid," he said. "What Professor Kimura says is not exaggerated at all. It's easy to tell that those relics were not caused by earthquakes."

Boston University's Schoch, meanwhile, is just as certain that the Yonaguni formations are natural.

He suggests that holes in the rock, which Kimura believes were used to support posts, were merely created by underwater eddies scouring at depressions.

Lines of smaller holes were formed by marine creatures exploiting a seam in the rock, he said.

"The first time I dived there, I knew it was not artificial," Schoch said. "It's not as regular as many people claim, and the right angles and symmetry don't add up in many places."

He emphasizes that he is not accusing anyone of deliberately falsifying evidence.

But many of the photos tend to give a perfect view of the site, making the lines look as regular as possible, he said.

Schoch also says he has seen what Kimura believes to be renderings of animals and human faces at the site.

"Professor Kimura says he has seen some kind of writing or images, but they are just scratches on a rock that are natural," he said.

"He interprets them as being manmade, but I don't know where he's coming from."

But Kimura is undeterred by critics, adding that the new governor of Okinawa Prefecture and officials from the United Nations Educational, Scientific, and Cultural Organization have recently expressed interest in verifying the site.

"The best way to get a definitive answer about their origins is to keep going back and collecting more evidence," he continued.

"If I'd not had a chance to see these structures for myself, I might be skeptical as well."

The Mommy Gene

Is there really a 'mommy' gene in women?

Basic principles of biology rather than women’s newfound economic independence can explain why fewer of them are getting married and having children, and why the trend may only be temporary, says a Queen’s researcher.

“Only in recent times have women acquired significant control over their own fertility, and many are preferring not to be saddled with the burden of raising children,” says Lonnie Aarssen, a Biology professor who specializes in reproductive ecology. The question is whether this is just a result of economic factors and socio-cultural conditioning, as most analysts claim, or whether the choices that women are making about parenthood are influenced by genetic inheritance from maternal ancestors that were dominated by paternal ancestors.”

In a paper published in the current issue of Oikos – an international journal of ecology – Dr. Aarssen suggests that because of inherited inclinations, many women when empowered by financial independence are driven to pursue leisure and other personal goals that distract from parenthood.

“The drive to leave a legacy through offspring can be side-tracked by an attraction to legacy through other things like career, fame, and fortune – distractions that, until recently, were only widely available to men”.

Dr. Aarssen speculates that the now widespread incidence of childlessness in developed countries will subside, not because of cultural evolution but because of biological evolution.

The women who leave the most descendants will be those with an intrinsic drive for motherhood. The ones who would rather forego parenthood in order to have a career, lavish vacations and leisurely lifestyles will of course leave no descendants at all. Over time those genetic traits that influence women away from motherhood will necessarily be ‘bred out.’

In this way future generations of women will inherit a stronger genetic predisposition for mating and having children as a priority in their lives. Dr. Aarssen predicts that an increased desire for marriage and having children, in both men and women, will be an inevitable product of evolution within the next few generations.

“The bottom line from a biology viewpoint is: in order to have your genes live on, you’ve got to have kids. If you don’t, then they’re going to disappear,” says Dr. Aarssen.

Source: Queen's University

Farmer Grows Pumpkins with Human Faces (Jan, 1938)

Modern Mechanix » Farmer Grows Pumpkins with Human Faces

What do ya do with a drunken sailor?

International Talk Like a Pirate Day - Wikipedia, the free encyclopedia

International Talk Like a Pirate Day

International Talk Like a Pirate Day (ITLAPD) is a parodic holiday invented in 1995 by John Baur ("Ol' Chumbucket") and Tim Laugel ("Cap'n Slappy"), of the United States, who proclaimed September 19 each year as the day when everyone in the world should talk like a pirate.[1] For example, an observer of this holiday would greet friends not with "Hello," but with "Ahoy, me haarrty!" The date was selected because it was the birthday of Summers' ex-wife and consequently would be easy for him to remember.
The holiday is of particular importance to Pastafarians (those who follow the teachings of the Church of the Flying Spaghetti Monster) who consider pirates to be absolute divine beings and the original Pastafarians.^[8]

Lift the skin up, and put into the bunt the slack of the clews (not
too taut), the leech and foot-rope, and body of the sail; being careful
not to let it get forward under or hang down abaft.
Then haul your bunt well up on the yard, smoothing the skin and
bringing it down well abaft, and make fast the bunt gasket round the mast, and the jigger, if there be one, to the tie.

—Richard Henry Dana, Jr., The Seaman's Manual (1844)

If the ship go before the wind, or as they term it, betwixt two sheets, then he who conds uses these terms to him at the helm: Starboard, larboard, the helm amidships... If the ship go by a wind, or a quarter winds, they say aloof, or keep your loof, or fall not off, wear no more, keep her to, touch the wind, have a care of the lee-latch. all these do imply the same in a manner, are to bid him at the helm to keep her near the wind.

—former pirate Sir Henry Mainwaring (see Harland (1984) p.177

Needles and Pins

Needles and pins,

Needles and pins,

Sew me a sail

To catch me the wind.

Sew me a sail

Strong as the gale,

Carpenter, bring out your

Hammers and nails.

Hammers and nails,

Hammers and nails,

Build me a boat

To go chasing the whales.

Chasing the whales,

Sailing the blue

Find me a captain

And sign me a crew.

Captain and crew,

Captain and crew,

Take me, oh take me

To anywhere new.

-Shel Silverstein

Kryptonite?

Villagers in southern Peru were struck by a mysterious illness after a meteorite made a fiery crash to Earth in their area, regional authorities said Monday.
Around midday Saturday, villagers were startled by an explosion and a fireball that many were convinced was an airplane crashing near their remote village, located in the high Andes department of Puno in the Desaguadero region, near the border with Bolivia.

Residents complained of headaches and vomiting brought on by a "strange odor," local health department official Jorge Lopez told Peruvian radio RPP.

Seven policemen who went to check on the reports also became ill and had to be given oxygen before being hospitalized, Lopez said.

Rescue teams and experts were dispatched to the scene, where the meteorite left a 100-foot-wide (30-meter-wide) and 20-foot-deep (six-meter-deep) crater, said local official Marco Limache.

"Boiling water started coming out of the crater and particles of rock and cinders were found nearby. Residents are very concerned," he said.

Make an offer

Internet auction website eBay on Monday withdrew an unusual second-hand sale item, the country of Belgium, which had attracted an offer of 10 million euros (13.9 million dollars).

"Belgium, a kingdom in three parts" was posted on the Belgian ebay site as offering "plenty of choice" despite the caveat that it comes with "300 billion of National Debt."

Offered in three parts -- Flanders, Brussels and Wallonia -- the accompanying blurb said the kingdom "can be bought as a whole (not recommended)."

The vendor also included as added extras "the king and his court (costs not included)."

Ebay spokesman Peter Burin said the site could not host the sale of anything virtual or "unrealistic," the Belga news agency reported.

The 'vendor' was named as a former journalist, Gerrit Six. Offering his lot at an initial price of one euro, he saw 26 subsequent bids culminating in the 10 million euro offer on Monday before the auction was halted.

Waves -the water kind

BBC NEWS | UK | England | Cornwall | Wave hub gets planning go-ahead

Wave hub gets planning go-ahead


The government has given planning approval for the world's first large-scale wave project off the coast of north Cornwall.

Sited 10 miles (16km) out to sea off Hayle, the hub - which would collect energy from wave turbines - could generate electricity for 14,000 homes.

It should deliver electricity to the national grid by 2009.

It is hoped the project could generate £330m for the regional economy over 25 years.


We look forward to using the same energy we've used to ride waves to light up our homes as well
Andy Cummins, Surfers Against Sewage

The official consent announcement will be made on Monday by John Hutton, Secretary of State for Business, Enterprise and Regulatory Reform.

The Wave Hub - a seafloor "socket", will connect wave energy machines to the mainland.

The proposed power station will involve up to 20 sets of machines, with pumps, pistons and turbines, about 10 miles (16km) out to sea off St Ives Bay, generating electricity for 14,000 homes.

There was some objection to the scheme among surfers who were worried the farm would reduce wave height on the beaches.

Pelamis: Ocean Prospect Ltd
Up to 10 Pelamis devices could be tested

But Dr Kerry Black, a New Zealand-based physical oceanographer, concluded in June that the impact on wave height would be less than 5% - far less than the 11% feared previously by some surfers.

The environmental campaign group, Surfers Against Sewage (SAS), has welcomed the project.

Andy Cummins, SAS Campaigns Officer, said: "Wave hub's government approval is good news for Cornwall and for the future of renewable energy generation in the UK.

"We look forward to using the same energy we've used to ride waves to light up our homes as well."

The implications of the project for the region's economy are considerable according to Claire Gibson from the South West RDA.

"It's a really exciting project for the region," she said.

"It's really going to position us as the place to be."

Four wave device developers have already been chosen for the scheme which will also be a testing site, allowing companies that develop wave energy technology to test their devices.

Up to 30 wave energy devices are expected to be deployed at the Wave Hub and will float on the surface of the sea.