Research reveals genetic link to human intelligence

University of Manchester scientists, working with colleagues in Edinburgh and Australia, have provided the first direct biological evidence for a genetic contribution to people’s intelligence.

Previous studies on twins and adopted people suggested that there is a substantial genetic contribution to thinking skills, but this new study – published in the journal Molecular Psychiatry – is the first to find a genetic contribution by testing people’s DNA for genetic variations.

The team studied two types of intelligence in more than 3,500 people from Edinburgh, Aberdeen, Newcastle and Manchester. The paper, by Dr Neil Pendleton and colleagues, found that 40% to 50% of people’s differences in these abilities could be traced to genetic differences.

The study examined more than half a million genetic markers on every person in the study. The new findings were made possible using a new type of analysis invented by Professor Peter Visscher and colleagues in Brisbane. As well as the findings in people from Scotland and England, the team checked their results in a separate group of people from Norway.

Dr Pendleton, who led the Manchester team in the Centre for Integrated Genomic Research, said: “This is the first reported research to examine the intelligence of healthy older adults and, using a comprehensive genetic survey, we were able to show a substantial genetic contribution in our ability to think.

“The study confirms the earlier findings of the research in twins. However, that research could not show which genes were or were not contributing to cognitive ability. Our work demonstrates that the number of individual genes involved in intelligence is large, which is similar to other human traits, such as height.

“We can now use the findings to better understand how these genes interact with each other and the environment, which has an equally significant contribution. With our collaborators, we will take this work forward to find the biological mechanisms that could maintain our intellectual abilities and wellbeing in late life. ”

The study, in collaboration with Professor Ian Deary at the University of Edinburgh, was funded in Manchester by the Biotechnology and Biological Sciences Research Council.

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Scientists have new help finding their way around brain's nooks and crannies

Scientists have found a way to use MRI scanning data to map myelin, a white sheath that covers some brain cell branches. Such maps, previously only available via dissection, help scientists determine precisely where they are at in the brain. Red and yellow indicate regions with high myelin levels; blue, purple and black areas have low myelin levels. Credit: David Van Essen

Like explorers mapping a new planet, scientists probing the brain need every type of landmark they can get. Each mountain, river or forest helps scientists find their way through the intricacies of the human brain.

Researchers at Washington University School of Medicine in St. Louis have developed a new technique that provides rapid access to brain landmarks formerly only available at autopsy. Better brain maps will result, speeding efforts to understand how the healthy brain works and potentially aiding in future diagnosis and treatment of brain disorders, the researchers report in the Journal of Neuroscience Aug. 10.

The technique makes it possible for scientists to map myelination, or the degree to which branches of brain cells are covered by a white sheath known as myelin in order to speed up long-distance signaling. It was developed in part through the Human Connectome Project, a $30 million, five-year effort to map the brain's wiring. That project is headed by Washington University in St. Louis and the University of Minnesota.

"The brain is among the most complex structures known, with approximately 90 billion neurons transmitting information across 150 trillion connections," says David Van Essen, PhD, Edison Professor and head of the Department of Anatomy and Neurobiology at Washington University. "New perspectives are very helpful for understanding this complexity, and myelin maps will give us important insights into where certain parts of the brain end and others begin."

Easy access to detailed maps of myelination in humans and animals also will aid efforts to understand how the brain evolved and how it works, according to Van Essen.

Neuroscientists have known for more than a century that myelination levels differ throughout the cerebral cortex, the gray outer layer of the brain where most higher mental functions take place. Until now, though, the only way they could map these differences in detail was to remove the brain after death, slice it and stain it for myelin.

Washington University graduate student Matthew Glasser developed the new technique, which combines data from two types of magnetic resonance imaging (MRI) scans that have been available for years.

"These are standard ways of imaging brain anatomy that scientists and clinicians have used for a long time," Glasser says. "After developing the new technique, we applied it in a detailed analysis of archived brain scans from healthy adults."

As in prior studies, Glasser's results show highest myelination levels in areas involved with early processing of information from the eyes and other sensory organs and control of movement. Many brain cells are packed into these regions, but the connections among the cells are less complex. Scientists suspect that these brain regions rely heavily on what computer scientists call parallel processing: Instead of every cell in the region working together on a single complex problem, multiple separate teams of cells work simultaneously on different parts of the problem.

Areas with less myelin include brain regions linked to speech, reasoning and use of tools. These regions have brain cells that are packed less densely, because individual cells are larger and have more complex connections with neighboring cells.

"It's been widely hypothesized that each chunk of the cerebral cortex is made up of very uniform information-processing machinery," Van Essen says. "But we're now adding to a picture of striking regional differences that are important for understanding how the brain works."

According to Van Essen, the technique will make it possible for the Connectome project to rapidly map myelination in many different research participants. Data on many subjects, acquired through many different analytical techniques including myelination mapping, will help the resulting maps cover the range of anatomic variation present in humans.

"Our colleagues are clamoring to make use of this approach because it's so helpful for figuring out where you are in the cortex, and the data are either already there or can be obtained in less than 10 minutes of MRI scanning," Glasser says.

More information: Mapping human cortical areas in vivo based on myelin content as revealed by T1- and T2-weighted MRI. The Journal of Neuroscience, Aug. 10, 2011.

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Tanning bed users exhibit brain changes and behavior similar to addicts

 Psychology & Psychiatry 

People who frequently use tanning beds may be spurred by an addictive neurological reward-and-reinforcement trigger, researchers at UT Southwestern Medical Center have found in a pilot study.

This could explain why some people continue to use tanning beds despite the increased risk of developing melanoma, the most lethal form of skin cancer. The brain activity and corresponding blood flow tracked by UT Southwestern scientists involved in the study is similar to that seen in people addicted to drugs and alcohol.

"Using tanning beds has rewarding effects in the brain so people may feel compelled to persist in the behavior even though it's bad for them," said Dr. Bryon Adinoff, professor of psychiatry and senior author of the study available online and in a future print edition of Addiction Biology. "The implication is, 'If it's rewarding, then could it also be addictive?' It's an important question in the field."

About 120,000 new cases of melanoma are diagnosed in the U.S. each year, according to the Skin Cancer Foundation. People younger than 30 who use a tanning bed 10 times a year have eight times the risk of developing malignant melanoma. While public knowledge of these dangers has grown, so has the regular use of tanning beds.

In this study, participants used tanning beds on two separate occasions: one time they were exposed to ultraviolet radiation and another time special filters blocked exposure to ultraviolet radiation. Participants did not know on which session they received the real or the filtered ultraviolet exposure. At each visit, participants were asked before and after each session how much they felt like tanning. Participants were also administered a compound that allowed scientists to measure brain blood flow while they were tanning.

Dr. Adinoff, who also is a staff physician at the Veterans Affairs North Texas Health Care System, said the next step is to create technology to further study brain changes among frequent tanners.

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Narcissism may benefit the young, researchers report; but older adults? Not so much

 Psychology & Psychiatry 

We all know one, or think we do: the person whose self-regard seems out of proportion to his or her actual merits. Popular culture labels these folks "narcissists," almost always a derogatory term. But a new study suggests that some forms of narcissism are – at least in the short term – beneficial, helping children navigate the difficult transition to adulthood.

The study appears in the journal Social Psychological and Personality Science.

"Most people think of narcissism as a trait that doesn't change much across the lifespan," said postdoctoral researcher Patrick Hill, who conducted the study with University of Illinois psychology professor Brent Roberts. "But a lot of recent studies have shown that the developmental trajectory of narcissism goes upward in adolescence and what we call emerging adulthood – the late teens and early 20s, and then typically declines."

This reduction in narcissistic traits coincides with a decline in their usefulness, the researchers found.

Hill and Roberts surveyed 368 undergraduate college students and 439 of their family members to get a picture of the narcissistic traits of the students and of their mothers. (There were enough mothers but not other relatives in the study to provide a robust sample size for analysis.)

"We looked at three different forms of narcissism," Hill said. The first, an inflated sense of leadership or authority, is the belief "that you know a lot and people should come to you for advice," he said. The second is "grandiose exhibitionism," being pompous, wanting to show off, and having an exaggerated sense of one's capabilities and talents. The third is a sense of entitlement and a willingness to exploit others for personal gain.

In the study, young people who were high in the leadership and grandiose exhibitionism forms of narcissism were likely to report higher life satisfaction and well-being, while mothers who had the same traits were not.

A sense of entitlement or willingness to exploit others for personal gain predicted lower life satisfaction at every age, however.

In general, participants had a lower opinion of those with narcissistic traits. Narcissistic mothers, in particular, tended to be viewed as neurotic and low in conscientiousness, the researchers found. Students who were narcissistic were not generally judged to be neurotic, but they and their narcissistic mothers were more likely to be viewed as low in "agreeableness."

These negative judgments, particularly of older adults, "could have quite interesting negative ramifications for people's circumstances in middle and old age if they retain this rather grandiose sense of self," Roberts said.

"This study continues a line of research that shows that there is a fundamental developmental shift in both the amounts of narcissism that people have and also in the meaning of it as people age," Roberts said. An exaggerated belief in one's own capabilities and prospects may help young people "navigate adolescence and the turmoil involved in trying to find a sense of identity," he said. Later in life, however, those same traits "appear to be related to less life satisfaction and a poorer reputation."

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Comment:
But what if you really are brilliant?

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Think fast: The neural circuitry of reaction time

 Neuroscience 

The voluntary movements we make must be "prepared" in our brain before they are executed. However, be it perfect timing, a false-start, or a delayed reaction, the neural circuitry underlying movement preparation is not well understood. Now a new study provides intriguing insight into how a neural circuit forms a motor plan. The research, published by Cell Press in the August 11 issue of the journal Neuron, uses a new type of analysis to assess the moment-by-moment firing rate of neurons in the brain to accurately predict the reaction time for making an arm movement.

We often prepare movements in anticipation of events, such as pressing the accelerator in the car when a traffic light turns green, but our reaction time can be frustratingly variable. Sometimes we are too slow to react, while other times we perform the movement before we are fully ready. "What is the cause of this imprecision?" asks senior study author, Dr. Krishna V. Shenoy from Stanford University.

"Presumably, it is related to the neural operation of planning and executing movements." Based on earlier observation that neural activity follows a movement-dependent trajectory during preparation, Dr. Shenoy's group in collaboration with co-senior author Dr. Maneesh Sahani from University College London developed a hypothesis called the "initial condition hypothesis." It states that during movement preparation, the network firing activity in the motor system is brought to a suitable initial condition from which the sequence of neural commands that underlies a movement may be efficiently generated.

To test their new hypothesis, the researchers simultaneously recorded from tens to hundreds of neurons in the monkey premotor cortex, a part of the brain associated with the control of movement, while the animals were performing delayed-reach movements. The monkeys had extensive training in the movement and exhibited stereotypical neural activity trajectories, making it possible for the researchers to compare subtle differences in activity. "We found that the degree to which the neural activity had advanced, and the speed with which it had been advancing, along this trajectory at the time of the 'go' cue contributed substantially to determining reaction time," explains Dr Shenoy. "To our knowledge, the initial condition hypothesis leads to the best known trial-by-trial predictor of fluctuations in reaction time. Future studies are needed to determine whether reaction time can be predicted with similar accuracy under less-stereotypical conditions with untrained subjects."

More information: Afshar et al.: “Single-Trial Neural Correlates of Arm Movement Preparation” Neuron.

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Narcissists look like good leaders -- but they aren't

 Psychology & Psychiatry 

(Medical Xpress) -- Narcissists rise to the top. That's because other people think their qualities—confidence, dominance, authority, and self-esteem—make them good leaders.

Is that true? "Our research shows that the opposite seems to be true," says Barbora Nevicka, a PhD candidate in organizational psychology, describing a new study she undertook with University of Amsterdam colleagues Femke Ten Velden, Annebel De Hoogh, and Annelies Van Vianen. The study found that the narcissists' preoccupation with their own brilliance inhibits a crucial element of successful group decision-making and performance: the free and creative exchange of information and ideas. The findings will be published in an upcoming issue of Psychological Science, a journal of the Association for Psychological Science.

The study recruited 150 participants and divided them into groups of three. One person was randomly assigned to be the group's leader; all were told they could contribute advice, but that the leader was responsible for making the decision. Then they undertook a group task: choosing a job candidate. Of 45 items of information about the candidate, some were given to all three, and some to only one of the participants.

The experiment was designed so that using only the information all three were privy to, the group would opt for a lesser candidate. Sharing all the information, including what each possessed exclusively, would lead to the best choice. Afterwards, the participants completed questionnaires. The leaders' questions measured narcissism; the others assessed the leaders' authority and effectiveness. All checked off the items among the 45 that they knew—indicating how much the group had shared—and rated how well they'd exchanged information. Experimenters tallied the number of shared items, noted the objective quality of the decision, and analyzed these data in relation to the leader's narcissism.

As expected, the group members rated the most narcissistic leaders as most effective. But they were wrong. In fact, the groups led by the greatest egotists chose the worse candidate for the job. Says Nevicka, "The narcissistic leaders had a very negative effect on their performance. They inhibited the communication because of self-centeredness and authoritarianism."

Narcissism can sometimes be useful in a leader, says Nevicka. In a crisis, for instance, people feel that a strong, dominant person will take control and do the right thing, "and that may reduce uncertainty and diminish stress."

But in the everyday life of an organization, "communication—sharing of information, perspectives, and knowledge—is essential to making good decisions. In brainstorming groups, project teams, government committees, each person brings something new. That's the benefit of teams. That's what creates a good outcome." Good leaders facilitate communication by asking questions and summarizing the conversation—something narcissists are too self-involved to do.

Nevicka says the research has implications beyond the workplace—for instance, in politics. "Narcissists are very convincing. They do tend to be picked as leaders. There's the danger: that people can be so wrong based on how others project themselves. You have to ask: Are the competencies they project valid, or are they merely in the eyes of the beholder?"

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A little exercise may protect the aging brain from memory loss following infection

 Neuroscience 

Microglia -- the immune defense cells of the brain shown here -- become more reactive to infection during aging. Researchers found a small amount of exercise protected older rats from memory loss following infection and prevented the exaggerated response of microglia in the brain’s learning and memory center. Credit: Reprinted with permission: Milligan, et al., The Journal of Neuroscience 2001, 21(8):2808-19.

A small amount of exercise shields older animals from memory loss following a bacterial infection, according to a study in the August 10 issue of The Journal of Neuroscience. The findings suggest moderate exercise may lead to several changes in the brain that boost its ability to protect itself during aging — a period of increased vulnerability.

In the new study, researchers led by Ruth Barrientos, PhD, of the University of Colorado at Boulder, found running on an exercise wheel protected older rats from memory loss following an Escherichia coli (E. coli) infection. Wheel-running also blunted changes in the hippocampus — an area of the brain involved in learning and memory — that typically follow bacterial infection in aging animals. In humans, older adults are more likely than the young to suffer memory impairment following severe bacterial infection or injury.

"This is the first study to show that exercise reduces susceptibility to the cognitive impairments that follow infection in aging animals, and the changes taking place in the brain thought to underlie these impairments," Barrientos said.

Bacterial infections kick off a cascade of events that signal the brain that something is wrong. Barrientos and colleagues previously found older rats experienced memory loss following E. coli infection, an outcome not seen in young adult rats. They also found the microglia — immune defense cells in the brain — of older animals became more reactive to infection, releasing more chemicals involved in inflammation in the hippocampus, in contrast with younger animals.

In the current study, the researchers allowed unlimited access to a running wheel to determine if exercise could help block the events that follow E. coli infection in the aging animals. Although the old rats only ran an average of 0.43 miles per week (50 times less distance than the young rats), they performed better on a memory test than rats who only had access to a locked exercise wheel. Additionally, the runners performed as well on the memory test as rats that were not exposed to E. coli. The small amount of exercise performed by the aging rats also prevented the reactive response of microglia in the hippocampus.

"While many of us are hopeful about developing a pharmaceutical intervention to reverse the effects of aging, this study provides exciting evidence that a little moderate exercise is protective against age-related problems with health and immunity," said Jonathan Godbout, PhD, an expert on aging at Ohio State University, who was unaffiliated with the study.

More information: http://www.jneurosci.org/

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Heritability of Intelligence

A new study of thousands of people in Europe quantifies the genetic underpinnings of intelligence, finding that some 50 percent of smarts stems from genes.

By Tia Ghose | August 9, 2011

Human fetal neural stem cellsFlickr, GE Healthcare

In at least one population, about half of intelligence differences between individuals can be attributed to genetics—specifically, the sum of many small effects from hundreds or even thousands of genes. The study, published today (August 9) in Molecular Psychiatry, is the first to pin down the genetic influence on cognitive abilities.

“The value of this paper is that it is the first clear and empirical demonstration that part of intelligence comes down to something which is writ in DNA,” said Patrick Sullivan, a psychiatric geneticist at University of North Carolina Chapel Hill, who was not involved in the study.

For decades, scientists have fiercely debated how much of the variation in individual intelligence can be attributed to genes. Studies of identical twins have suggested that 60-80 percent of intelligence comes down to genes, but “the controversy in the past has been, ‘well, maybe there’s just no separating out nature and nurture,’” said study co-author Peter Visscher, a quantitative geneticist at the Queensland Institute of Medical Research in Australia.

In addition, aside from the Alzheimer’s-linked APOE4 gene, researchers who went looking for “intelligence genes” have been unable to find them. Furthermore, many studies purporting to look at the heritability of intelligence have been accused of using faulty methodology or tweaking the data to justify racist beliefs.

To tease out the genetic differences directly, Visscher and his colleagues analyzed roughly 500,000 single nucleotide polymorphisms (SNPs) in about 3,500 adults aged 18 to 90 from the United Kingdom and Norway. The subjects took an array of vocabulary, speed of processing, and reasoning tests designed to measure intelligence.

Not surprisingly, they didn’t find any specific genes that were associated with higher cognitive abilities. Given the complexity of the trait, a single gene is unlikely to have a large effect on intelligence, meaning researchers would need a much larger sample size to detect those minute effects.

Instead, they were able to use a statistical technique to analyze the overall effect of genetics on smarts. Specifically, they used all 500,000 SNP locations to determine how genetically similar each subject was to every other individual in the study. They found that people who tested higher on intelligence were more genetically similar to each other than to those who scored lower in intelligence, and that roughly half of the variation in intelligence between individuals could be attributed to underlying genes. The results suggest that hundreds or even thousands of genes may each contribute a small amount to intelligence. But what those genes are remains a mystery.

One way to find those genes would be to increase the sample size by pooling genetic data from all studies on intelligence, Visscher said.

The findings also have a number of other limitations, researchers said. First, the study participants were mostly older adults, born as early as 1921, and thus represented a biased population—those healthy enough to still be alive, said geneticist Dorret Boomsma, who leads the Netherlands Twins Register at the VU University in Amsterdam, and was not involved in the study. The study population is also inherently biased because the selection criteria make it a nonrandom sample.

In addition, some researchers have questioned the statistical methods used, said Greg Gibson, director of the Center for Integrative Genomics at Georgia Institute of Technology who was not involved in the study. Because the researchers sampled only a small subset of the SNPs in the human genome, most of which are not in the actual genes that may affect intelligence, its quantitative estimate is not predictive of the larger population, he said. So even though genetics predicted about half of the variation in intelligence within their sample population, what they found would only predict about 1 percent of the variance in intelligence across the wider population in Northern Europe, Gibson said.

Finally, the study is only applicable to intelligence in populations they studied, Gibson added. “This study says absolutely nothing about differences between groups,” such as people of different ethnicities.

Davies, G., et. al, “Genome-wide association studies establish that human intelligence is highly heritable and polygenic,” Molecular Psychiatry, doi: 10.1038/mp.2011.85, 2011.

Source: TheScientist
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Exotic Quantum Crystal Discovered: Researchers Discover Novel State of Crystal Matter

Density distribution of the quantum particles (excitons) in the plane of the quantum well. Yellow color corresponds to high density, red to lower, green to zero. From top left to bottom right the density is increased at constant temperature. (Credit: Michael Bonitz, ITAP, CAU Kiel)

Science Daily  — Nature knows two opposite types of solids: one that emerges upon compression from a liquid and a second that appears if the pressure on a liquid is reduced. While the former is typical for substances in our everyday life the latter occurs for example in a dense quantum liquid of electrons (such as in metals) or ions (in exotic white dwarf or neutron stars).

A team from Kiel University (Germany) consisting of Dr. Jens Bönning, Privatdozent Alexei Filinov and Prof. Michael Bonitz has performed extensive accurate computer simulations that shed light on the mysterious properties of this material.Now it has been shown that there exists yet a third form of matter that inherits both of these properties. This unusual behaviour has been predicted to exist in crystals of excitons -- hydrogen atom-like bound states of electrons and holes -- in a semiconductor quantum well placed in a strong electric field.

The results appear in the current issue of Physical Review B. There the authors present a simple explanation for the coexistence of the two seemingly contradicting melting behaviours.

The secret lies in the character of the forces acting between two excitons: at low pressure excitons repel each other via a dipole force and form a quantum liquid. Upon compression this fluid freezes into an exciton crystal. Further compression brings two excitons so close together that the quantum wave nature of their constituents (electrons and holes) starts to weaken the forces. As a consequence, further compression leads to an increasing overlap of the exciton quantum waves that is no longer balanced by the inter-exciton repulsion, and the crystal melts again.

The researchers have made precise predictions where to search for this exotic crystal of excitons (particularly well suited are zinc selenide or gallium arsenide quantum wells) -- it is now up to the experimentalists to find this new state of matter.

Study Builds On Plausible Scenario for Origin of Life On Earth

The natural enantiomer of the RNA precursor molecules formed a crystal structure visible to the naked eye. (Credit: Image courtesy of University of California - Merced)

Science Daily — A relatively simple combination of naturally occurring sugars and amino acids offers a plausible route to the building blocks of life, according to a paper published in Nature Chemistry.

Biological molecules, such as RNA and proteins, can exist in either a natural or unnatural form, called enantiomers. By studying the chemical reactions carefully, the research team found that it was possible to generate only the natural form of the necessary RNA precursors by including simple amino acids.

The study shows how the precursors to RNA could have formed on Earth before any life existed. It was authored by Jason E. Hein, Eric Tse and Donna G. Blackmond, a team of researchers with the Scripps Research Institute. Hein is now a chemistry professor with University of California, Merced.

"These amino acids changed how the reactions work and allowed only the naturally occurring RNA precursors to be generated in a stable form," said Hein. "In the end, we showed that an amazingly simple result emerged from some very complex and interconnected chemistry."

The natural enantiomer of the RNA precursor molecules formed a crystal structure visible to the naked eye. The crystals are stable and avoid normal chemical breakdown. They can exist until the conditions are right for them to change into RNA.

The study was led by Blackmond and builds on the work of John D. Sutherland and Matthew W. Powner published in 2009 and covered by outlets such as The New York Times and Wired. Sutherland is a chemist with Cambridge's Medical Research Council Laboratory of Molecular Biology. Powner is a post-doctoral scholar with Harvard University.

Solar Flares: What Does It Take to Be X-Class? Sun Emits an X-Class Flare On August 9, 2011

An X-class flare began at 3:48 AM EDT on August 9, 2011 and peaked at 4:05 AM. The flare burst from sun spot region AR11263, before it rotated out of view. The image here was captured by NASA's Solar Dynamics Observatory in extreme ultraviolet light at 131 Angstroms. (Credit: NASA)

Science Daily  — Solar flares are giant explosions on the sun that send energy, light and high speed particles into space. These flares are often associated with solar magnetic storms known as coronal mass ejections (CMEs). The number of solar flares increases approximately every 11 years, and the sun is currently moving towards another solar maximum, likely in 2013. That means more flares will be coming, some small and some big enough to send their radiation all the way to Earth.

C-class and smaller flares are too weak to noticeably affect Earth. M-class flares can cause brief radio blackouts at the poles and minor radiation storms that might endanger astronauts.The biggest flares are known as "X-class flares" based on a classification system that divides solar flares according to their strength. The smallest ones are A-class (near background levels), followed by B, C, M and X. Similar to the Richter scale for earthquakes, each letter represents a 10-fold increase in energy output. So an X is ten times an M and 100 times a C. Within each letter class there is a finer scale from 1 to 9.And then come the X-class flares. Although X is the last letter, there are flares more than 10 times the power of an X1, so X-class flares can go higher than 9. The most powerful flare measured with modern methods was in 2003, during the last solar maximum, and it was so powerful that it overloaded the sensors measuring it. The sensors cut out at X28.

The biggest X-class flares are by far the largest explosions in the solar system and are awesome to watch. Loops tens of times the size of Earth leap up off the sun's surface when the sun's magnetic fields cross over each other and reconnect. In the biggest events, this reconnection process can produce as much energy as a billion hydrogen bombs.

If they're directed at Earth, such flares and associated CMEs can create long lasting radiation storms that can harm satellites, communications systems, and even ground-based technologies and power grids. X-class flares on December 5 and December 6, 2006, for example, triggered a CME that interfered with GPS signals being sent to ground-based receivers.

NASA and NOAA -- as well as the US Air Force Weather Agency (AFWA) and others -- keep a constant watch on the sun to monitor for X-class flares and their associated magnetic storms. With advance warning many satellites and spacecraft can be protected from the worst effects.

On August 9, 2011 at 3:48 a.m. EDT, the sun emitted an Earth-directed X6.9 flare, as measured by the NOAA GOES satellite. These gigantic bursts of radiation cannot pass through Earth's atmosphere to harm humans on the ground, however they can disrupt the atmosphere and disrupt GPS and communications signals. In this case, it appears the flare is strong enough to potentially cause some radio communication blackouts. It also produced increased solar energetic proton radiation -- enough to affect humans in space if they do not protect themselves.

There was also a coronal mass ejection (CME) associated with this flare. CMEs are another solar phenomenon that can send solar particles into space and affect electronic systems in satellites and on Earth. However, this CME is not traveling toward and Earth so no Earth-bound effects are expected.

Deep Recycling in Earth Faster Than Thought

These are olivine crystals from Mauna Loa volcano, Hawaii, with a width of less than 1 mm. The brown ovals are solidified, glassy inclusions trapped as droplets of melt by the growing olivine crystal. They contain strontium isotope ratios which are inherited from 500-million-year-old seawater. (Credit: Sobolev, Max Planck Institute for Chemistry.)

Science Daily — The recycling of Earth's crust in volcanoes happens much faster than scientists have previously assumed. Rock of the oceanic crust, which sinks deep into the earth due to the movement of tectonic plates, reemerges through volcanic eruptions after around 500 million years. Researchers from the Max Planck Institute for Chemistry in Mainz obtained this result using volcanic rock samples. Previously, geologists thought this process would take about two billion years.

The chemical analysis of tiny glassy inclusions in olivine crystals from basaltic lava on Mauna Loa volcano in Hawaii has now surprised geologists: the entire recycling process requires at most half a billion years, four times faster than previously thought.Virtually all of the ocean islands are volcanoes. Several of them, such as Hawaii, originate from the lowest part of the mantle. This geological process is similar to the movement of coloured liquids in a lava lamp: hot rock rises in cylindrical columns, the so-called mantle plumes, from a depth of nearly 3000 kilometres. Near the surface, it melts, because the pressure is reduced, and forms volcanoes. The plume originates from former ocean crust which early in Earth's history sank to the bottom of the mantle. Previously, scientists had assumed that this recycling took about two billion years.

The microscopically small inclusions in the volcanic rock contain trace elements originally dissolved in seawater, and this allows the recycling process to be dated. Before the old ocean crust sinks into the mantle, it soaks up seawater, which leaves tell-tale trace elements in the rock. The age is revealed by the isotopic ratio of strontium which changes with time. Strontium is a chemical element, which occurs in trace amounts in sea water. The isotopes of chemical elements have the same number of protons but different numbers of neutrons. Mainz scientists developed a special laser mass spectrometry method which allowed the detection of isotopes of strontium in extremely small quantities.

To their surprise, the Max Planck researchers found residues of sea water with an unexpected strontium isotope ratio in the samples, which suggested an age of less than 500 million years for the inclusions. Therefore the rock material forming the Hawaiian basalts must be younger.

"Apparently strontium from sea water has reached deep in the Earth's mantle, and reemerged after only half a billion years, in Hawaiian volcano lavas," says Klaus Peter Jochum, co-author of the publication. "This discovery was a huge surprise for us."

Another surprise for the scientists was the tremendous variation of strontium isotope ratios found in the melt inclusions in olivine from the single lava sample. "This variation is much larger than the known range for all Hawaiian lavas," says Alexander Sobolev. "This finding suggests that the mantle is far more chemically heterogeneous on a small spatial scale than we thought before." This heterogeneity is preserved only by melt inclusions but is completely obliterated in the lavas because of their complete mixing.

Sobolev, Jochum and their colleagues expect to obtain similar results for other volcanoes and therefore be able to determine the recycling age the ocean crust more precisely

Baker's yeast protects against fatal infections

by Biomechanics 

Injecting mice with simple baker's yeast protects against the fatal fungal infection, aspergillosis, according to research published in the Journal of Medical Microbiology. The work could lead to the development of a human vaccine that protects immunocompromised people against a range of life-threatening fungal infections, for which current therapy often fails. 

Researchers from the California Institute for Medical Research, Santa Clara Valley Medical Center and Stanford University gave mice three injections of killed Saccharomyces (baker's yeast), one week apart. Vaccinated mice were able to survive high doses of Aspergillus – the fungus that causes aspergillosis. Mice that survived also showed a reduced infection load in their organs.

Aspergillosis is the leading fungal killer among immunocompromised individuals. It is an invasive infection that attacks the lungs, can disseminate to other organs, such as the brain, and can lead to kidney and liver failure. The disease currently has very high mortality as the current available therapy has a high failure rate. 

The research team used a simple yeast preparation as a vaccine against Aspergillus in mice. They found that unmodified yeast gave just as much protection against the development of aspergillosis as yeasts that had been engineered to display Aspergillus surface proteins. Dr. David A. Stevens, from Santa Clara Valley Medical Center, in whose laboratory the studies were performed, said, "Our results suggest that the protective component of the yeast is in the cell wall. What's more, the simple preparation we used has been shown by us to also protect against infection due to three other fungi that cause human disease –Candida, Cryptococcus and Coccidioides." 

Baker's yeast is being studied by other groups in human clinical trials for other purposes and appears to be safe. "Research to date, including our study, supports the development of a yeast vaccine against all pathogenic fungi that infect humans. Such a 'panfungal' vaccine would further reduce mortality in immunocompromised individuals," explained Dr. Stevens. "While vaccinating all individuals with impaired immune systems would be a formidable challenge, there are certain patient groups that might be the initial target of a vaccine effort. These include transplant candidates, leukemics following induction therapy and also patients diagnosed with solid tumours."