Michigan State University

This Clear Solar Cell Could Turn Every Window Into A Power Source.

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Researchers from Michigan State University have developed a transparent solar cell capable of being used as a replacement for windows!

This Clear Solar Cell Could Turn Every Window Into A Power Source

This concept was once deemed impossible, due to the fact traditional solar panels absorb light and convert it into energy. Transparent surfaces are not capable of absorbing light. Researchers accomplished this feat by developing a system called transparent luminescent solar concentrator (TLSC), which is composed of organic salts which absorb non-visible wavelengths of infrared and ultraviolet light. This light is then focused towards a traditional solar cell which is capable of trapping the energy and turning it into electricity. This material has unbelievable potential. Not only can it be utilized for windows, but it could revolutionize displays on electronic devices, giving them a significantly longer battery life.

Ventilatory Support May Help Children With Cerebral Malaria

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Most deaths in children with cerebral malaria may be due to increased brain volume leading to raised intracranial pressure, according to research from Malawi.

Therefore, a therapeutic approach “that capitalizes on the fact that, in survivors, the brain swelling resolves over one to two days, would be to treat the effect of brain swelling, which is respiratory arrest,” Dr. Terrie E. Taylor, of Michigan State University in Lansing told Reuters Health by email.

In fact, she concluded, “It may be that providing ventilatory support would be enough to, in effect, tide the children over the vulnerable period.”

In a March 19 online paper in The New England Journal of Medicine, Dr. Taylor and colleagues note that case fatality rates among African children with cerebral malaria remain in the range of 15% to 25%.

Magnetic resonance imaging (MRI) became available in Malawi in 2009, and the team used it to investigate the role of brain swelling in 168 children with the disease.

In all, 25 (15%) of these children died, including 21 (84%) with evidence of severe brain swelling on MRI at admission. However, severe brain swelling was seen in only 39 (27%) of the 143 survivors. In addition, serial MRI scans showed evidence of decreasing brain volume in the survivors who had brain swelling initially.

“Among survivors, the volume increase was transient, and the long-term outcomes were similar to those observed in survivors with normal brain volumes, suggesting that interventions that decrease brain swelling or sustain respiration temporarily, while the brain is swollen, may reduce mortality without increasing morbidity,” the authors conclude.

Solar energy that doesn’t block the view

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Researchers have developed a new type of solar concentrator that when placed over a window creates solar energy while allowing people to actually see through the window. It is called a transparent luminescent solar concentrator and can be used on buildings, cell phones and any other device that has a flat, clear surface.
Solar power with a view: MSU doctoral student Yimu Zhao holds up a transparent luminescent solar concentrator module.
Credit: Yimu Zhao

A team of researchers at Michigan State University has developed a new type of solar concentrator that when placed over a window creates solar energy while allowing people to actually see through the window.

It is called a transparent luminescent solar concentrator and can be used on buildings, cell phones and any other device that has a clear surface.

And, according to Richard Lunt of MSU’s College of Engineering, the key word is “transparent.”

Research in the production of energy from solar cells placed around luminescent plastic-like materials is not new. These past efforts, however, have yielded poor results — the energy production was inefficient and the materials were highly colored.

“No one wants to sit behind colored glass,” said Lunt, an assistant professor of chemical engineering and materials science. “It makes for a very colorful environment, like working in a disco. We take an approach where we actually make the luminescent active layer itself transparent.”

The solar harvesting system uses small organic molecules developed by Lunt and his team to absorb specific nonvisible wavelengths of sunlight.

“We can tune these materials to pick up just the ultraviolet and the near infrared wavelengths that then ‘glow’ at another wavelength in the infrared,” he said.

The “glowing” infrared light is guided to the edge of the plastic where it is converted to electricity by thin strips of photovoltaic solar cells.

“Because the materials do not absorb or emit light in the visible spectrum, they look exceptionally transparent to the human eye,” Lunt said.

One of the benefits of this new development is its flexibility. While the technology is at an early stage, it has the potential to be scaled to commercial or industrial applications with an affordable cost.

“It opens a lot of area to deploy solar energy in a non-intrusive way,” Lunt said. “It can be used on tall buildings with lots of windows or any kind of mobile device that demands high aesthetic quality like a phone or e-reader. Ultimately we want to make solar harvesting surfaces that you do not even know are there.”

Lunt said more work is needed in order to improve its energy-producing efficiency. Currently it is able to produce a solar conversion efficiency close to 1 percent, but noted they aim to reach efficiencies beyond 5 percent when fully optimized. The best colored LSC has an efficiency of around 7 percent.

The research was featured on the cover of a recent issue of the journal Advanced Optical Materials.

Other members of the research team include Yimu Zhao, an MSU doctoral student in chemical engineering and materials science; Benjamin Levine, assistant professor of chemistry; and Garrett Meek, doctoral student in chemistry.

Story Source:

The above story is based on materials provided by Michigan State University. Note: Materials may be edited for content and length.

Journal Reference:

  1. Yimu Zhao, Garrett A. Meek, Benjamin G. Levine, Richard R. Lunt. Light Harvesting: Near-Infrared Harvesting Transparent Luminescent Solar Concentrators (Advanced Optical Materials 7/2014). Advanced Optical Materials, 2014; 2 (7): 599 DOI: 10.1002/adom.201470040

New neutrino cooling theory changes understanding of neutron stars’ surfaces.

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Massive X-ray superbursts near the surface of neutron stars are providing a unique window into the operation of fundamental forces of nature under extreme conditions.
X-ray nebula
A small, dense object only 12 miles in diameter is responsible for this beautiful X-ray nebula that spans 150 light years. At the center of this image made by NASA’s Chandra X-ray Observatory is a very young and powerful pulsar, known as PSR B1509-58 (B1509). The pulsar is a rapidly spinning neutron star which is spewing energy out into the space around it to create complex and intriguing structures, including one that resembles a large cosmic hand.
NASA
Massive X-ray superbursts near the surface of neutron stars are providing a unique window into the operation of fundamental forces of nature under extreme conditions.“Scientists are intrigued by what exactly powers these massive explosions, and understanding this would yield important insights about the fundamental forces in nature, especially on the astronomical–cosmological scale,” said Peter Moller of Los Alamos National Laboratory’s Theoretical Division.A neutron star is created during the death of a giant star more massive than the Sun, compressed to a tiny size but with gravitational fields exceeded only by those of black holes. And in the intense neutron-rich environment, nuclear reactions cause strong explosions that manifest themselves as X-ray bursts and the X-ray superbursts that are more rare and 1,000 times more powerful.The importance of discovering an unknown energy source of titanic magnitude in the outermost layers of accreting neutron star surfaces is heightened by the unresolved issue of neutrino masses, the recent discovery of the Higgs boson, and the fact that highly neutron-rich nuclei with low-lying states enable “weak interactions,” prominent in stellar explosions. The weak nuclear force is one of four fundamental sources, such as gravity, that interact with the neutrinos; it is responsible for some types of radioactive decay.These hitherto celestially operative nuclei are expected to be within the experimental reach of the Facility for Rare Isotope Beams (FRIB), a proposed user facility at Michigan State University (MSU) funded by the U.S. Department of Energy Office of Science.

Previously, a common assumption was that that the energy released in these radioactive decays would power the X-ray superburst explosions. This was based on simple models of nuclear beta decay, sometimes postulating the same decay properties for all nuclei. It turns out, however, that it is of crucial importance to develop computer models that realistically describe the shape of each individual nuclide since they are not all spherical.

At Los Alamos, scientists have carried out detailed calculations of the specific individual beta-decay properties of thousands of nuclides, all with different decay properties, and created databases with these calculated properties.

The databases are then used at MSU as input into models that trace the decay pathways with the passage of time in accreting neutron stars and compute the total energy that is released in these reactions.

The new unexpected result is that so much energy escapes by neutrino emission that the remaining energy released in the beta decays is not sufficient to ignite the X-ray superbursts that are observed. Thus the superbursts’ origin has now become a puzzle.

Solving the puzzle will require that scientists calculate in detail the consequences of shapes of neutron-rich nuclei, the authors said, and it requires that they simultaneously analyze the role played by neutrinos in neutron star X-ray bursts whose energetic magnitudes are exceeded only by explosions in the nova–supernova class.

The strong nuclear deformations that formed the basis for the neutrino cooling in neutron star crusts also play a role in a number of astrophysical settings and have been taken into account in studies of supernova explosions and subsequent collapses.

 

New formula for fast, abundant hydrogen production may help power fuel cells.

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Scientists in Lyon, a French city famed for its cuisine, have discovered a quick-cook recipe for copious volumes of hydrogen (H2).

The breakthrough suggests a better way of producing the  that propels rockets and energizes battery-like fuel cells. In a few decades, it could even help the world meet key energy needs—without carbon emissions contributing to the greenhouse effect and climate change.

It also has profound implications for the abundance and distribution of life, helping to explain the astonishingly widespread microbial communities that dine on hydrogen deep beneath the continents and seafloor.

Describing how to greatly speed up nature’s process for producing hydrogen will be a highlight among many presentations by Deep Carbon Observatory (DCO) experts at the American Geophysical Union‘s annual Fall Meeting in San Francisco Dec. 9 to 13.

The DCO is a global, 10-year international science collaboration unraveling the mysteries of Earth’s inner workings—deep life, energy, chemistry, and fluid movements.

Muriel Andreani, Isabelle Daniel, and Marion Pollet-Villard of University Claude Bernard Lyon 1 discovered the quick recipe for producing hydrogen:

In a microscopic high-pressure cooker called a diamond anvil cell (within a tiny space about as wide as a pencil lead), combine ingredients: aluminum oxide, water, and the mineral olivine. Set at 200 to 300 degrees Celsius and 2 kilobars pressure—comparable to conditions found at twice the depth of the deepest ocean. Cook for 24 hours. And voilà.

Dr. Daniel, a DCO leader, explains that scientists have long known nature’s way of producing hydrogen. When water meets the ubiquitous mineral olivine under pressure, the rock reacts with oxygen (O) atoms from the H2O, transforming olivine into another mineral, serpentine—characterized by a scaly, green-brown surface appearance like snake skin. Olivine is a common yellow to yellow-green mineral made of magnesium, iron, silicon, and oxygen.

The process also leaves hydrogen (H2) molecules divorced from their marriage with oxygen atoms in water.

The novelty in the discovery, quietly published in a summer edition of the journal American Mineralogist, is how aluminum profoundly accelerates and impacts the process.

Finding the reaction completed in the diamond-enclosed micro space overnight, instead of over months as expected, left the scientists amazed. The experiments produced H2 some 7 to 50 times faster than the natural “serpentinization” of olivine.

Over decades, many teams looking to achieve this same quick hydrogen result focused mainly on the role of iron within the olivine, Dr. Andreani says. Introducing aluminum into the hot, high-pressure mix produced the eureka moment.

Dr. Daniel notes that aluminum is Earth’s 5th most abundant element and usually is present, therefore, in the natural serpentinization process. The experiment introduced a quantity of aluminum unrealistic in nature.

Jesse Ausubel, of The Rockefeller University and a founder of the DCO program, says current methods for commercial hydrogen production for fuel cells or to power rockets “usually involve the conversion of methane (CH4), a process that produces the greenhouse gas carbon dioxide (CO2) as a byproduct. Alternatively, we can split water molecules at temperatures of 850 degrees Celsius or more—and thus need lots of energy and extra careful engineering.”

“Aluminum’s ability to catalyze hydrogen production at a much lower temperature could make an enormous difference. The cost and risk of the process would drop a lot.”

“Scaling this up to meet global energy needs in a carbon-free way would probably require 50 years,” he adds. “But a growing market for hydrogen in fuel cells could help pull the process into the market.”

“We still need to solve problems for a hydrogen economy, such as storing the hydrogen efficiently as a gas in compact containers, or optimizing methods to turn it into a metal, as pioneered by Russell Hemley of the Carnegie Institution‘s Geophysical Laboratory, another co-founder of the DCO.”

Deep energy, Dr. Hemley notes, is typically thought of in terms of geothermal energy available from heat deep within Earth, as well as subterranean fluids that can be burned for energy, such as methane and petroleum. What may strike some as new is that there is also chemical energy in the form of hydrogen produced by serpentinization.

At the time of the AGU Fall Meetings, Dr. Andreani will be taking a lead role with Javier Escartin of the Centre National de la Recherche Scientifique in a 40-member international scientific exploration of fault lines along the Mid-Atlantic Ridge. It is a place where the African and American continents continue to separate at an annual rate of about 20 mm (1.5 inches) and rock is forced up from the mantle only 4 to 6 km (2.5 to 3.7 miles) below the thin ocean floor crust. The study will advance several DCO goals, including the mapping of world regions where deep life-supporting H2 is released through serpentinization.

Aboard the French vessel Pourquoi Pas?, using a deep sea robot from the French Research Institute for Exploitation of the Sea (IFREMER), and a deep-sea vehicle from Germany’s Leibniz Institute of Marine Sciences (GEOMAR), the team includes researchers from France, Germany, USA, Wales, Spain, Norway and Greece.

Notes Dr. Daniel, until now it has been a scientific mystery how the rock + water + pressure formula produces enough hydrogen to support the chemical-loving microbial and other forms of life abounding in the hostile environments of the deep.

With the results of the experiment in France, “for the first time we understand why and how we have H2 produced at such a fast rate. When you take into account aluminum, you are able to explain the amount of life flourishing on hydrogen,” says Dr. Daniel.

Indeed, DCO scientists hypothesize that hydrogen was what fed the earliest life on primordial planet Earth—first life’s first food.

And, she adds: “We believe the serpentinization process may be underway on many planetary bodies—notably Mars. The reaction may take one day or one million years but it will occur whenever and wherever there is some water present to react with olivine—one of the most abundant minerals in the solar system.”

Enigmatic evidence of a deep subterranean microbe network

Meanwhile, the genetic makeup of Earth’s deep microbial life is being revealed through DCO research underway by Matt Schrenk of Michigan State University, head of DCO’s “Rock-Hosted Communities” initiative, Tom McCollom of the University of Colorado, Boulder, Steve D’Hondt of the University of Rhode Island, and many other associates.

At AGU, they will report the results of deep sampling from opposite sides of the world, revealing enigmatic evidence of a deep subterranean microbe network.

Using DNA, researchers are finding hydrogen-metabolizing microbes in rock fractures deep beneath the North American and European continents that are highly similar to samples a Princeton University group obtained from deep rock fractures 4 to 5 km (2.5 to 3 miles) down a Johannesburg-area mine shaft. These DNA sequences are also highly similar to those of microbes in the rocky seabeds off the North American northwest and northeastern Japanese coasts.

“Two years ago we had a scant idea about what microbes are present in subsurface rocks or what they eat,” says Dr. Schrenk. “Since then a number of studies have vastly expanded that database. We’re getting this emerging picture not only of what sort of organisms are found in these systems but some consistency between sites globally—we’re seeing the same types of organisms everywhere we look.”

“It is easy to understand how birds or fish might be similar oceans apart, but it challenges the imagination to think of nearly identical microbes 16,000 km apart from each other in the cracks of hard rock at extreme depths, pressures, and temperatures” he says.

A hydrogen bubble is quickly released as olivine meets water and aluminum oxide under extreme pressure and heat. Credit: Muriel Andreani, University of Lyon-1

“In some deep places, such as deep-sea hydrothermal vents, the environment is highly dynamic and promotes prolific biological communities,” says Dr. McCollom. “In others, such as the deep fractures, the systems are isolated with a low diversity of microbes capable of surviving such harsh conditions.”

“The collection and coupling of microbiological and geochemical data made possible through the Deep Carbon Observatory is helping us understand and describe these phenomena.”

How water behaves deep within Earth’s mantle

Among other major presentations, DCO investigators will introduce a new model that offers new insights into water / rock interactions at extreme pressures 150 km (93 miles) or more below the surface, well into Earth’s upper mantle. To now, most models have been limited to 15 km, one-tenth the depth.

“The DCO gives a happy twist to the phrase ‘We are in deep water’,” says researcher Dimitri Sverjensky of Johns Hopkins University, Baltimore MD.

Dr. Sverjensky’s work, accepted for publication by the Elsevier journal Geochimica et Cosmochimica Acta, is expected to revolutionize understanding of deep Earth water chemistry and its impacts on subsurface processes as diverse as diamond formation, hydrogen accumulation, the transport of diverse carbon-, nitrogen- and sulfur-fed species in the mantle, serpentinization, mantle degassing, and the origin of Earth’s atmosphere.

In deep Earth, despite extreme high temperatures and pressures, water is a fluid that circulates and reacts chemically with the rocks through which it passes, changing the minerals in them and undergoing alteration itself—a key agent for transporting carbon and other chemical elements. Understanding what water is like and how it behaves in Earth’s deep interior is fundamental to understanding the deep carbon cycle, deep life, and deep energy.

This water-rock interaction produces valuable ore deposits, creates the chemicals on which deep life and deep energy depend, influences the generation of magma that erupts from volcanoes—even the occurrence of earthquakes. Humanity gets glimpses of this water in hot springs.

Says Dr. Sverjensky: “The new model may enable us to predict water-rock interaction well into Earth upper mantle and help visualize where on Earth H2 production might be underway.”

The DCO is now in the 5th year of a decade-long adventure to probe Earth’s deepest geo-secrets: How much carbon is stored inside Earth? What are the reservoirs of that carbon? How does carbon move among reservoirs? How much carbon released from Earth’s deep interior is primordial and how much is recycled from the surface? Are there deep abiotic sources of hydrocarbons? What is the nature and extent of deep microbial life? And did deep Earth chemistry play a role in life’s origins?

The $500 million global collaboration is led by Dr. Robert Hazen, Senior Staff Scientist at the Geophysical Laboratory, Carnegie Institution of Washington.

Says Dr. Hazen: “Bringing together experts in microbes, volcanoes, the micro-structure of rocks and minerals, fluid movements, and more is novel. Typically these experts don’t connect with each other. Integrating such diversity in a single scientific endeavor is producing insights unavailable until the DCO.”

Ninety percent or more of Earth’s carbon is thought to be locked away or in motion deep underground, he notes, a hidden dimension of the planet as poorly understood as it is profoundly important to life on the surface.

 

Report Finds ‘Culture of Resistance’ on Youth Concussion.

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Young athletes in the United States face a “culture of resistance” to telling a coach or parent they might have a concussion, according to a new report from the Institute of Medicine and National Research Council. 

The 306-page report, “Sports-Related Concussions in Youth: Improving the Science, Changing the Culture,” was released during a briefing today at the National Academy of Sciences in Washington, DC.

“Even though there is an increased willingness to report a concussion, there is still the desire on the part of the athlete not to report it because they feel they are letting their teammates down; on the part of the coaches because it upsets the team they have on the field, or their own belief that, ‘I had these, I’m okay, it’s just part of the sport’; and on the part of the parents who want to see their children excel and be accepted,” said Robert Graham, MD, chair of the committee that wrote the report.

Attitude Adjustment

Efforts are needed to “change the culture,” said Dr. Graham, who is director of the National Program Office for Aligning Forces for Quality at George Washington University in Washington, DC.

Over 9 months, the committee did a comprehensive review of the literature on concussions in youth sports with athletes aged 5 to 21 years. 

“The findings of our report justify the concerns about sports concussions in young people,” said Dr. Graham. “However, there are numerous areas in which we need more and better data.  Until we have that information, we urge parents, schools, athletic departments, and the public to examine carefully what we do know, as with any decision regarding risk, so they can make more informed decisions about young athletes playing sports,” he added.

The reported number of individuals aged 19 and under treated in US emergency departments for concussions and other nonfatal sports- and recreation-related traumatic brain injuries (TBIs) increased from 150,000 in 2001 to 250,000 in 2009.

“This could possibly be due to an increase in awareness or reporting of concussions,” committee member Tracey Covassin, PhD, director of the undergraduate athletic training program at Michigan State University in East Lansing. “However, we do not know the true incidence of concussions as several concussions go unreported, as well as a lack of consistency in terminology with different studies that have reported different definitions of concussions.”

The committee found that the majority of research into concussions is at the high school and collegiate levels, with very few to no data reported below the high school level.

The committee also found a “shift” in the incidence of concussions, with more reported at the high school level than the collegiate level, Dr. Covassin said.

Football, ice hockey, lacrosse, wrestling, and soccer are associated with the highest rates of reported concussions for male athletes at the high school and college levels, while soccer, lacrosse, and basketball are associated with the highest rates of reported concussions for female athletes at these levels of play.

Limited Evidence Helmets Cut Risk

The committee found little evidence that current sports helmet designs cut the risk for concussions. 

“What the literature tells us is that diffuse brain injuries like concussion are caused by a combination of linear and rotational forces,” explained committee member Kristy Arbogast, PhD, engineering core director, Center for Injury Research and Prevention, Children’s Hospital of Philadelphia in Pennsylvania. “What we do know is that helmets reduce that linear portion. There is limited evidence that they can manage the rotational components of the impact. This is in part due to standards.”

The committee stressed, however, that properly fitted helmets, face masks, and mouth guards should still be used because they reduce the risk for other injuries.

The committee also examined the scientific literature on concussion recognition, diagnosis, and management. They found that the signs and symptoms of concussion are usually placed into 4 categories — physical, cognitive, emotional, and sleep — with patients having 1 or more symptoms from 1 or more categories. 

Most youth athletes with concussion will recover within 2 weeks of the injury, but in 10% to 20% of cases concussion symptoms persist for several weeks, months, or even years. 

Return to Play

The committee advises that a concussed athlete return to play only when he or she has recovered demonstrably and is no longer having any symptoms. An individualized treatment plan that includes physical and mental rest may be beneficial for recovery from a concussion, but current research does not suggest a standard or universal level and duration of rest needed, the committee notes.

Athletes who return to play before complete recovery are at increased risk for prolonged recovery or more serious consequences if they sustain a second concussion. “The evidence is pretty clear” on this, said committee member Arthur Maerlender, PhD, director of pediatric neuropsychological services at Dartmouth-Hitchcock Medical Center in Lebanon, New Hampshire.

The literature also suggests that single and multiple concussions can lead to impairments in the areas of memory and processing speed.  However, it remains unclear whether repetitive head impacts and multiple concussions sustained in youth lead to long-term neurodegenerative disease, such as chronic traumatic encephalopathy, the committee said.

It notes, however, that surveys of retired professional athletes provide some evidence that a history of multiple concussions increases risk for depression. In a survey of more than 2500 retired professional football players, approximately 11% reported having clinical depression. “Very little” research has evaluated the relationship between concussions and suicidal thoughts and behaviors, the committee notes.

In youth sports, several organizations have called for a “hit count” to limit the amount of head contact a player receives over a given amount of time. Although this concept is “fundamentally sound,” the committee found that implementing a specific threshold for the number of impacts or the magnitude of impacts per week or per season is without scientific basis.

The committee calls for establishing a national surveillance system to accurately determine the number of sports-related concussions, identify changes in the brain following concussions in youth, conduct studies to assess the consequences and effects of concussions over a life span, and evaluate the effectiveness of sports rules and playing practices in reducing concussions. 

To Stop Malaria, Infect the Mosquitoes.

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malaria

For thousands of years, mosquitoes have made people sick. But now humanity may have found a way to turn the tables. In a new study, researchers report that giving mosquitoes an infection of their own—with a strange bacterium that tinkers with the insects’ sex lives—may prevent mosquitoes from transmitting malaria.

The advance is being hailed by some as a milestone in medical entomology. “I’m quite jealous,” says entomologist Scott O’Neill of Monash University in Australia, who was not involved in the work. “We have all tried this for years and years and years.” The mosquito species in question, Anopheles stephensi, is a key malaria vector in South Asia and the Middle East, and the study offers the tantalizing possibility of ridding entire cities such as New Delhi and Calcutta of malaria, says Willem Takken of Wageningen University in the Netherlands, who was also not involved in the work. In the future, the same technique might also work for other malaria-carrying mosquitoes, such as A. gambiae, which predominates in Africa, Takken says.

Scientists have long dreamed of replacing disease-carrying mosquito populations with new ones that pose no threat to humans because they cannot transmit disease. In the past decade, a bacterium called Wolbachia has emerged as a promising ally in their work. These intracellular bacteria spread from insect mothers to their offspring and play some bizarre tricks on their hosts’ sex lives. For instance, by ensuring that infected males can’t reproduce with uninfected females—a phenomenon called cytoplasmic incompatibility—the bacteria can maximize the number of infected offspring in the next generation and sweep through populations in very little time.

Scientists’ initial idea was to introduce genes conferring resistance to human pathogens into mosquitoes, and then enlist Wolbachia to help these traits race through the population. The difficult part was infecting mosquitoes with Wolbachia in the first place; for some reason, they seemed not amenable to a long-term, stable infection. A landmark came in a 2005 Science paper, in which Xi Zhiyong, then at Johns Hopkins University in Baltimore, Maryland, and colleagues infected a mosquito species called Aedes aegypti, which is the main carrier for dengue fever, a debilitating viral disease that causes intense muscle and joint pains.

A few years later, O’Neill and others made a startling discovery: They didn’t even need to couple Wolbachia to infection resistance genes. The bacterium alone made Ae. aegypti unable to transmit the virus. Others have shown that the same was true for several other viruses and parasites.

It’s not clear exactly why this is; one hypothesis is that Wolbachia competes for resources with other intruders, such as the dengue virus. But that hasn’t stopped scientists from trying to make use of the phenomenon. In 2011, O’Neill’s group released Wolbachia-infected Ae. aegypti mosquitoes in Australia, where they found that the infection took hold and spread. Currently, experiments are also underway in Vietnam, where dengue is an important disease.

But dengue isn’t the biggest mosquito-borne killer; that’s malaria, which is responsible for the deaths of more than half a million people annually and is transmitted by Anopheles mosquitoes, a very different genus. They have proven even more difficult to infect with Wolbachia. The frustrating quest — and the fact that not a singleAnopheles species is known to be naturally infected with the bacteria — had led some researchers to question whether it was possible at all, O’Neill says.

But Xi, who now leads his own group at Michigan State University in East Lansing, has done it again. In a new study reported online today inScience, the researchers showed that they can infect A. stephensi withWolbachia, that the infection is passed down through at least 34 generations, and that it can take over entire populations in cages.

The secret? Part of it is luck, Takken says. The team worked with a strain called Wolbachia wAlbB that happened to catch on in this mosquito. Technical skill is another factor, says entomologist Jason Rasgon of Pennsylvania State University, University Park, who wasn’t involved in the work. Injecting mosquito eggs is “very much an art,” he says, and Xi “is probably the best person in the world to do it.”

The team had to inject thousands of embryos before they had success. Xi says part of the trick is to suck a minuscule amount of cytoplasm out of egg cells first to make room for the injected bacteria and prevent cells from bursting. Despite their horrendous death toll, Anopheles mosquitoes are delicate critters, he says.

Xi’s group also fed infected mosquitoes malaria parasites to test whether Wolbachia could block their life cycle inside the mosquito’s body. They showed that Wolbachia-infected mosquitoes didn’t become totally resistant to malaria, as hoped. Instead, the number of parasites in their saliva 14 days after their exposure went down only by about a factor of 3.4, which means the mosquitoes could still transmit the disease, although perhaps not as efficiently.

Another key issue is whether Wolbachia-infected mosquitoes can produce the same number of offspring as uninfected ones, Takken says. If they can’t, they won’t be able to outcompete wild populations, and the insects wouldn’t fly as a malaria control scheme. Xi says he plans to publish another paper on that issue. Studies are also needed to determine how many infected mosquitoes need to be released in the field to get results fast enough. There might be other Wolbachia strains that do the job better, Rasgon says. For now, what’s most important is that the researchers have succeeded in the first place, he says. He is inspired because his own group is trying to infect A. gambiae, the main malaria vector in Africa and an even more difficult target to infect. “It’s very good for me to see that it can actually be done,” he says. “We will keep pushing ahead.”

Source: sciencemag.org

California battle over GM labels.

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Voters in California will decide on a proposal next month that would require the labelling of most foods made with genetically modified ingredients.

Proposition 37 is supported by the organic industry but many major food suppliers oppose it saying it will drive up prices.

Around $40m is expected to be spent on campaigning with the majority coming from opponents.

But a recent opinion poll shows a clear majority in favour of the proposal.

There have been attempts in 18 states to change labelling laws on genetically modified foods via legislation. None have been successful.

But after a grassroots campaign that garnered more than a million signatures, the measure will be on the ballot paper in California for the first time next month.

If passed, the statute will require labelling on raw or processed food offered for sale to consumers if the food is made from plants or animals with genetic material changed in specified ways.

Foods containing these ingredients would be banned from using the word “natural”.

Supporters say that consumers have a right to know. More than 50 countries around the world require labelling. Why shouldn’t consumers in the US, the country with the largest proportion of their food containing GM?

“We already have food labels showing nutrition, allergy information and other facts consumers want to know. This measure simply adds information telling us if food is produced using genetic engineering,” said the Yes on 37 campaign group.

Those who oppose the measure say it is unfair to single out GM as something that requires labelling and not include antibiotics, pesticides or hormones used in production.

The No on 37 group is supported by farmers, business groups and food manufacturers. Their spokesperson Kathy Fairbanks told BBC News that the overall impact of will be higher prices.

“Proposition 37 is a poorly written law that gives inaccurate and misleading information and will raise grocery costs for California families by up to $400 a year,” she explained.

It is estimated that around $40m will be spent mainly on TV advertisements, in an attempt to convince people to vote for or against. The vast majority of the money, according to an analysis by independent researchers MapLight, comes from big biotechnology firms including Monsanto and Du Pont who, between them, have contributed around $12m.

Food is a complex and divisive issue in the United States. According to Dr Philip Howard from Michigan State University, labels don’t always tell the full story. Organic producers for instance have in many cases been taken over by big food manufacturers such as Kraft, Kellogg and PepsiCo.

“You can stroll through the shelves in the interior aisles of stores with all the processed products,” he told BBC News, “and well over half that are marked organic are going to be from big multinational companies.”

He says that confusingly, some of the money spent on food labelled organic will be going to fight the GM labelling proposition in California.

“People who are buying organic foods are not realising that the money is flowing to big corporations, and the donations to both sides of the campaign are illuminating the future of the food system people really want to support.”

Some commentators believe that the vote in California will have implications beyond the state. In an analysis of voter intentions that showed strong support for the measure, researchers at Oklahoma state university say the proposal could add to consumer confusion.

“Prop 37 could disrupt the flow of agricultural products to and from California and other parts of the United States and would lead to food companies having to deal with competing requirements in different parts of the country” the authors write.

Dr Philip Howard says that where California goes others will have to follow.

“As with other California labelling requirements, many manufacturers won’t go to the trouble and expense of having separate packaging for other states,” he said.

“Internationally the effect won’t be as direct, but it is likely to encourage governments that don’t already require labeling to adopt similar measures.”

The team will be mindful of the extreme difficulty a previous Mars mission, the Phoenix probe of 2008, had in getting material to go through its sample handling system.

“Phoenix had a relatively uncontrolled drop off capability; they had just the one scoop and that scoop had to do everything,” Mr Limonadi told BBC News.

“We use gravity and vibration to get things into little parts of Chimra that make very controlled volumes of portions for us to drop off.”

The rover has now driven at total of 484m (of about 1,590ft) since its 6 August landing on the floor of Gale Crater, a huge depression on Mars’ equator.

It still has about 176m to travel to get to a location dubbed Glenelg, a place satellite images have indicated is a junction between three different geological terrains.

It is at Glenelg where Curiosity will really get down to the business of investigating past environments in Gale.

Last week, scientists announced the robot had taken pictures of rocks that were clearly deposited in fast running water. The theory is that the rover is sitting at the head of an ancient alluvial fan where a network of streams cut across the crater floor billions of years ago.

Source:BBC

 

Save a bird: Turn off a light.

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It’s that time of the year when migratory birds do their thing, so today’s a good day to draw attention to an alarming article I read over the summer about an alleged hazard that could put an abrupt end to a feathery flight.

According to an article on the Michigan Radio website, birds are fatally smashing into communication transmission towers because the red warning lights confuse their navigation systems.

If this sounds like a, er, lark, get this: About 7 million misguided birds die annually in tower collisions in the U.S. and Canada, according to a study by the U.S. Fish and Wildlife Service. Among the most susceptible: neotropical songbirds that migrate at night. A Cornell University photo that accompanied the Michigan Radio article shows a number of deceased warblers among the birds that hit a TV tower near Elmira, N.Y. during 1999’s Hurricane Floyd.

Of course, those tower lights serve a purpose. They prevent pilots from smacking into the structures.

But at the same time, they can trip up the birds’ natural guidance system, which relies on the stars and the sun. On a cloudy or foggy night when the stars don’t show but the tower lights do, things can go disastrously haywire. Bye-bye blackbird.

Red and steadily burning lights – those that don’t blink – are the biggest culprits, according to Joelle Gehring, a senior conservation scientist at Michigan State University. She ran a test on Michigan State Police towers that reduced collisions by between 50 and 70 percent when the police turned of the constantly lit lights.

The Federal Aviation Administration says that on some towers, operators could turn off steady lights or replace them with blinkers without jeopardizing pilot safety – as long there were ample flashing lights, the article states.  Sounds like a solution that could fly.

Source: Smart Planet.