Physicists at the National Institute of Standards and Technology (NIST) have demonstrated the first "universal" programmable quantum information processor able to run any program allowed by quantum mechanics — the rules governing the submicroscopic world — using two quantum bits (qubits) of information. The processor could be a module in a future quantum computer, which theoretically could solve some important problems that are intractable today.

The NIST demonstration, described in Nature Physics, marks the first time any research group has moved beyond demonstrating individual tasks for a quantum processor — as done previously at NIST and elsewhere — to perform programmable processing, combining enough inputs and continuous steps to run any possible two-qubit program.

The NIST team also analyzed the quantum processor with the methods used in traditional computer science and electronics by creating a diagram of the processing circuit and mathematically determining the 15 different starting values and sequences of processing operations needed to run a given program. "This is the first time anyone has demonstrated a programmable quantum processor for more than one qubit," says NIST postdoctoral researcher David Hanneke, first author of the paper. "It`s a step toward the big goal of doing calculations with lots and lots of qubits. The idea is you`d have lots of these processors, and you`d link them together."

The NIST processor stores binary information (1s and 0s) in two beryllium ions (electrically charged atoms), which are held in an electromagnetic trap and manipulated with ultraviolet lasers. Two magnesium ions in the trap help cool the beryllium ions.

NIST scientists can manipulate the states of each beryllium qubit, including placing the ions in a "superposition" of both 1 and 0 values at the same time, a significant potential advantage of information processing in the quantum world. Scientists also can "entangle" the two qubits, a quantum phenomenon that links the pair`s properties even when the ions are physically separated.

With these capabilities, the NIST team performed 160 different processing routines on the two qubits. Although there are an infinite number of possible two-qubit programs, this set of 160 is large and diverse enough to fairly represent them, Hanneke says, making the processor "universal." Key to the experimental design was use of a random number generator to select the particular routines that would be executed, so all possible programs had an equal chance of selection. This approach was chosen to avoid bias in testing the processor, in the event that some programs ran better or produced more accurate outputs than others.

Ions are among several promising types of qubits for a quantum computer. If they can be built, quantum computers have many possible applications such as breaking today`s most widely used encryption codes, such as those that protect electronic financial transactions. In addition to its possible use as a module of a quantum computer, the new processor might be used as a miniature simulator for interactions in any quantum system that employs two energy levels, such as the two-level ion qubit systems that represent energy levels as 0s and 1s. Large quantum simulators could, for example, help explain the mystery of high-temperature superconductivity, the transmission of electricity with zero resistance at temperatures that may be practical for efficient storage and distribution of electric power.

The new paper is the same NIST research group`s third major paper published this year based on data from experiments with trapped ions. They previously demonstrated sustained quantum information processing and entanglement in a mechanical system similar to those in the macroscopic everyday world. NIST quantum computing research contributes to advances in national priority areas, such as information security, as well as NIST mission work in precision measurement and atomic clocks.

In the latest NIST experiments reported in Nature Physics, each program consisted of 31 logic operations, 15 of which were varied in the programming process. A logic operation is a rule specifying a particular manipulation of one or two qubits. In traditional computers, these operations are written into software code and performed by hardware.

The programs did not perform easily described mathematical calculations. Rather, they involved various single-qubit "rotations" and two-qubit entanglements. As an example of a rotation, if a qubit is envisioned as a dot on a sphere at the north pole for 0, at the south pole for 1, or on the equator for a balanced superposition of 0 and 1, the dot might be rotated to a different point on the sphere, perhaps from the northern to the southern hemisphere, making it more of a 1 than a 0.

Each program operated accurately an average of 79 percent of the time across 900 runs, each run lasting about 37 milliseconds. To evaluate the processor and the quality of its operation, NIST scientists compared the measured outputs of the programs to idealized, theoretical results. They also performed extra measurements on 11 of the 160 programs, to more fully reconstruct how they ran and double-check the outputs.

As noted in the paper, many more qubits and logic operations will be required to solve large problems. A significant challenge for future research will be reducing the errors that build up during successive operations. Program accuracy rates will need to be boosted substantially, both to achieve fault-tolerant computing and to reduce the computational "overhead" needed to correct errors after they occur, according to the paper.

As a non-regulatory agency of the U.S. Department of Commerce, NIST promotes U.S. innovation and industrial competitiveness by advancing measurement science, standards and technology in ways that enhance economic security and improve our quality of life.

Small amounts of oil leave a fluorescent sheen on polluted water. Oil sheen is hard to remove, even when the water is aerated with ozone or filtered through sand. Now, a University of Utah engineer has developed an inexpensive new method to remove oil sheen by repeatedly pressurizing and depressurizing ozone gas, creating microscopic bubbles that attack the oil so it can be removed by sand filters.

"We are not trying to treat the entire hydrocarbon [oil] content in the water — to turn it into carbon dioxide and water — but we are converting it into a form that can be retained by sand filtration, which is a conventional and economical process," says Andy Hong, a professor of civil and environmental engineering.

In laboratory experiments reported recently online in the journal Chemosphere, Hong demonstrated that "pressure-assisted ozonation and sand filtration" effectively removes oil droplets dispersed in water, indicating it could be used to prevent oil sheen from wastewater discharged into coastal waters.

Hong says the method — for which patents are pending — also could be used to clean a variety of pollutants in water and even soil, including:

• So-called "produced water" from oil and gas drilling sites on land. Such oily water normally is re-injected underground. "If we have technology to clean it, it could be put into beneficial uses, such as irrigation, especially in arid regions where oil and gas tend to be produced," says Hong.
• Water from mining of tar sands and oil shale.
• Groundwater contaminated by MTBE, a gasoline additive that reduces harmful vehicle emissions but pollutes water due to leaking underground gasoline storage tanks.
• "Emerging contaminants," such as wastewater polluted with medications and personal care products.
• Soil contaminated with polychlorinated biphenyls (PCBs, from electrical transformers) or polycyclic aromatic hydrocarbons (PAHs, from fuel burning). Water and contaminated soil would be mixed into slurry, and then treated with the new method.
• Heavy metals in soil. Instead of ozone, air and metal-grabbing chelating agents would be pressurized with a slurry of the contaminated material.
• Refinery wastewater and oil spills at refineries or on waterways. The spill could be vacuumed, and then treated with the new method on-site or on a barge.

Hong conducted the study with two University of Utah doctoral students — Zhixiong Cha, who has earned his Ph.D., and Chia-Jung Cheng — and with Cheng-Fang Lin, an environmental engineering professor at National Taiwan University.

Hong says his method uses two existing technologies — ozone aeration and sand filtration — and adds a big change to the former. Instead of just bubbling ozone through polluted water, Hong uses repeated cycles of pressurization of ozone and dirty water so the ozone saturates the water, followed by depressurization so the ozone expands into numerous microbubbles in the polluted water, similar to the way a carbonated beverage foams and overflows if opened quickly.

The tiny bubbles provide much more surface area — compared with larger bubbles from normal ozone aeration — for the oxygen in ozone to react chemically with oil. Hong says pollutants tend to accumulate on the bubbles because they are not very water-soluble. The ozone in the bubble attacks certain pollutants because it is a strong oxidant.

The reactions convert most of the dispersed oil droplets — which float on water to cause sheen — into acids and chemicals known as aldehydes and ketones. Most of those substances, in turn, help the remaining oil droplets clump together so they can be removed by conventional sand filtration, he adds.

In his study, Hong showed the new method not only removes oil sheen, but also leaves the treated water so that any remaining acids, aldehydes and ketones are more vulnerable to being biodegraded by pollution-eating microbes.

"These are much more biodegradable than the parent compounds," he says.

Hong says the water is clean enough to be discharged after the ozonation and sand filtration, but that some pollution sources may want to use conventional methods to biodegrade remaining dissolved organic material.

Hong conducted his experiments using a tabletop chemical reactor that contained about a quart of oily water made by mixing deionized water with crude oil from the Rangely oil field in northwestern Colorado.

Ozone was produced by passing dry air through a high-voltage field, converting oxygen gas, which has two oxygen atoms, into ozone, which has three.

The ozone was pressurized to 10 times atmospheric pressure, about 150 pounds per square inch, which compares with inflation pressures of about 100 PSI for Hong`s bicycle and 35 to 40 PSI for many automobile tires.

He found oily water was cleaned most effectively by pressurizing and depressurizing it with ozone gas 10 times, then filtering it through sand, then putting the water through 20 more pressurized ozone cycles, and then filtering it again through sand. That was at flow rates of 10 to 20 liters per minute [about 2.6 to 5.3 U.S. gallons per minute] in his laboratory apparatus.

Hong tested how well the ozonation worked by measuring chemical and biological oxygen demands of treated water samples. Both indirectly measure organic contents in the water. Hong also used mass spectrometry to identify what contaminants remained in the water.

He found that his most effective procedure removed 99 percent of the turbidity from the "produced water" — leaving it almost as clear as drinking water — and removed 83 percent of the oil, converting the rest to dissolved organic acids removable by biodegradation.

With success in the laboratory, Hong now plans for larger-scale pilot tests.

"It is economical and it can be scaled up," he says.

One such test will be done in Wuxi, China, where a prototype desk-sized device capable of treating 200 liters [53 U.S. gallons] at a time will be tested at three to five polluted industrial sites that the government vacated for redevelopment, Hong says.

Meanwhile, the University of Utah Research Foundation has entered into options to license the technology to Miracotech, Inc., of Albany, Calif., and 7Rev, L.P., a Salt Lake City venture capital group, so the companies can bring the technology to market.

Hong says other methods of treating oil well "produced water" have met with varying degrees of success. They include centrifuges, membranes, regular ozonation and air bubbles to float off contaminants. But all have drawbacks, such as inability to handle dissolved oil or high levels of oil, or susceptibility to quickly getting fouled by the oil.

Neither ozonation nor sand filtration alone has been able to effectively treat oily "produced water." Hong says long-chain oil molecules don`t react with ozone easily without his pressure treatment. And sand filters alone cannot remove oil.

Research at the Lund University Vision Group can now show that the color vision of birds stops working considerably earlier in the course of the day than was previously believed, in fact, in the twilight. Birds need between 5 and 20 times as much light as humans to see colors.

It has long been known that birds have highly developed color vision that vastly surpasses that of humans. Birds see both more colors and ultraviolet light. However, it was not known what amount of light is necessary for birds to see colors, which has limited the validity of all research on this color vision to bright sunlight only.

"Using behavioral experiments we can now demonstrate that birds lose their color vision in the twilight and show just how much light is needed for birds to be able to interpret color signals," says Olle Lind, a doctoral candidate at the Department of Cell and Organism Biology.

For humans and horses, color vision ceases to work after dusk, at light intensities roughly corresponding to bright moonlight. However, the light threshold is not the same for all vertebrates. Geckos, for instance, can see colors at night. In the experiments performed by the Lund University Vision Group, the color vision of birds stopped working at light intensities corresponding to what prevails shortly after the sun goes down. Birds need between 5 and 20 times as much light as humans to see colors. Among all the vertebrates tested thus far, birds are the first to lose their color vision in the twilight, even though they are the vertebrates that probably see colors best of all in the daylight.

With these findings it is now possible to start to draw conclusions about how birds use their color vision at dawn and dusk. The findings also direct our focus to previous research about how important color is when it comes to eggs or begging baby birds in enclosed nests. Inside enclosed nests it is dark even when the sun is bright outside.

"Against the background of our new discoveries, we should now re-evaluate earlier research about how birds perceive the color of their eggs and their young in the nest," says Olle Lind.

The research findings were recently published in Journal of Experimental Biology 2009, 212: pp. 3693-3699.

Plans to be discussed at the forthcoming UN climate conference in Copenhagen to cut deforestation in developing countries could save some species from extinction but inadvertently increase the risk to others, scientists believe.

A team of eleven of the world`s top tropical forest scientists, coordinated by the University of Leeds, warn that while cutting clearance of carbon-rich tropical forests will help reduce climate change and save species in those forests, governments could risk neglecting other forests that are home to large numbers of endangered species.

Under new UN Framework Convention on Climate Change (UNFCCC) proposals, the Reduced Emissions from Deforestation and Degradation (REDD) scheme would curb carbon emissions by financially rewarding tropical countries that reduce deforestation.

Governments implicitly assume that this is a win-win scheme, benefiting climate and species. Tropical forests contain half of all species and half of all carbon stored in terrestrial vegetation, and their destruction accounts for 18% of global carbon emissions.

However, in a paper published in the latest issue of Current Biology, the scientists warn that if REDD focuses solely on protecting forests with the greatest density of carbon, some biodiversity may be sacrificed.

"Concentrations of carbon density and biodiversity in tropical forests only partially overlap," said Dr Alan Grainger of the University of Leeds, joint leader of the international team. "We are concerned that governments will focus on cutting deforestation in the most carbon-rich forests, only for clearance pressures to shift to other high biodiversity forests which are not given priority for protection because they are low in carbon."

"If personnel and funds are switched from existing conservation areas they too could be at risk, and this would make matters even worse."

If REDD is linked to carbon markets then biodiversity hotspot areas — home to endemic species most at risk of extinction as their habitats are shrinking rapidly — could be at an additional disadvantage, because of the higher costs of protecting them.

According to early estimates up to 50% of tropical biodiversity hotspot areas could be excluded from REDD for these reasons. Urgent research is being carried out across the world to refine these estimates.

Fortunately, the UN Framework Convention on Climate Change is still negotiating the design of REDD and how it is to be implemented.

The team is calling for rules to protect biodiversity to be included in the text of the Copenhagen Agreement. It also recommends that the Intergovernmental Panel on Climate Change give greater priority to studying this issue, and to producing a manual to demonstrate how to co-manage ecosystems for carbon and biodiversity services.

"Despite the best of intentions, mistakes can easily happen because of poor design" said Dr Grainger. "Clearing tropical forests to increase biofuel production to combat climate change is a good example of this. Governments still have time at Copenhagen to add rules to REDD to ensure that it does not make a similar mistake. A well designed REDD can save many species and in our paper we show how this can be done."

Determining what triggers the death of retinal cells, called photoreceptors, could hold the key to stopping blinding disorders caused by a wide range of eye diseases, Yale School of Medicine researchers report in the November journal Investigative Ophthalmology & Visual Science.

Several blinding disorders are known to cause the breakdown of photoreceptors. Caroline Zeiss, associate professor of comparative medicine and ophthalmology at Yale School of Medicine, and her colleagues sought to identify a mechanism in photoreceptors that could be targeted to prolong their survival. Using preserved animal and human retinal tissue, they studied different diseases with a range of genetic mutations that caused photoreceptor death, such as age-related macular degeneration and retinal pigmentosa.

In the diseases Zeiss and her team studied, photoreceptors died from a variety of causes, but the team found that all of the diseases had one common element — activation of a family of molecules called CREB1/ATF1. It was unclear, however, whether CREB1/ATF1 contributed to photoreceptor loss, or was an attempt by photoreceptors to delay their death. To differentiate between these two possibilities, the team examined CREB1/ATF1 in retinas treated with a drug known to preserve photoreceptors. Protected photoreceptors expressed much higher amounts than unprotected retinas, suggesting that CREB1/ATF1 was part of the protective mechanism.

"Not only did we find that the drug activated the novel CREB1/ATF1 photoreceptor pathway, but we found that this activation was caused by stress," said Zeiss. "This suggests that CREB/ATF1 may be an innate protective response that could be used to achieve broad spectrum preservation of the retina."

"This is the first time that any protective signal within photoreceptors has been identified across such a broad range of eye diseases," Zeiss added. "By finding a common way in which photoreceptors react to stress, it may be possible to develop new therapies to preserve vision."

Zeiss said the next step in the research is to try to identify drug targets that could activate the CREB1/ATF1 pathway. The team could potentially screen thousands of compounds and look at their ability to turn on CREB1/ATF1 in retinal tissue.

Other authors on the study included William A. Beltran, Heather G. Allore, Elizabeth Johnson, Virginia Towle, Weng Tao, Gregory M. Acland and Gustavo D. Aguirre.

By matching children with rare or life-threatening diseases and modelling potential disease progression, researchers hope to find new routes forward.

Software tools are being developed that can search and compare patient data at hospitals across Europe to find children with closely matched conditions. The doctors can then study how the matched patients at other hospitals were treated and whether that treatment was successful. The information will greatly improve doctors` ability to choose the right path for their own patient.

The tools being developed within the Health-e-Child project can compare a vast range of structured and unstructured data, including genetic and clinical data, as well as images from CAT and MRI scans and other records.

The Health-e-Child system, protected by high security, links anonymised databases of patient information at hospitals in Paris, Genoa, Rome and London. There are plans to extend the network to 25 hospitals.

Health-e-Child researchers are working on tools for three complex paediatric diseases with at least partly unknown causes: heart diseases resulting from an overload of the right ventricle, juvenile idiopathic arthritis, and brain tumours (gliomas).

The EU-funded project has tackled fundamental data sharing infrastructural problems as well as ethical and data protection questions, data analysis and data mining issues. Both disease-specific and cross-disease tools have been developed.

For unstructured data such as images, the Health-e-Child project has created tools that translate visual information into machine-readable (and therefore machine-comparable) language. The project`s 3D registration tool for MRI scans, and its MRI `erosion scoring` system for juvenile idiomatic arthritis have been recognised as important advances in their fields.

Matching and modelling two in a million

Health-e-Child`s CaseReasoner tool enables clinicians to search thousands of disease diagnoses, treatments and outcomes to find a child similar to their own patients. The clinicians set the search parameters themselves. In the case of heart patients, clinicians could include factors they consider important, such as genetic markers, the age of the child, the heart rate — even the amount of exercise the child takes.

The results can be displayed as a `network` with cohorts of patients with similar diagnoses clustered together and colour-graded accorded to the level of similarity. Clinicians can then dive into the detailed data on any of the patients or clusters to better understand their diagnoses and the success of the procedures the patients have been through.

The CaseReasoner could also be used to search out the procedures that have been most successful, giving the clinician insights into the optimal path forward.

The AITION tool, being developed by Health-e-Child researchers at the University of Athens, seeks to go further. AITION will use semantic tools to search medical literature and interviews with clinicians as well as patient data. Drawing on well-established causal-probability algorithms, AITION will suggest probable disease development. Doctors using AITION will then be able to test their hypotheses on optimal treatment.

Other Health-e-Child researchers have combined a heart modelling tool called CardioWiz with MRI scan measurement software from Siemens, according to Siemens Healthcare`s Martin Huber, technical leader of the Health-e-Child project.

The combination can rapidly generate animated 3D models of a particular patient`s heart. The patient`s doctors can play with the models and simulate the effects of heart surgery or drug treatments to see how the heart would respond.

Child diseases under-researched

The lack of research into child disease adds to the significance of Health-e-Child, says Jörg Freund, from Siemens Healthcare and Health-e-Child project coordinator. Because the numbers of children suffering from these diseases are small, there is little incentive for commercial companies to research them. Some pharmaceutical companies calculate drug doses for children simply on weight — treating the child as a mini-adult. This fails to take account of important differences between children and adults. The most obvious difference is that children are growing.

Research on children can give important insights into the role of genetics in disease. Environmental factors can be less important in child diseases, simply because there has usually not been time in the child`s short life for the environment to have had much effect.

The Health-e-Child project received funding from the ICT strand of the EU`s Sixth Framework Programme for research.

To best detect early signs of life-threatening heart defects in young athletes, screening programs should include both popular diagnostic tests, not just one of them, according to new research from heart experts at Johns Hopkins.

Sudden cardiac death due to heart rhythm disturbances is blamed for more than 3,000 deaths a year in young people, especially athletes who have inherited tendencies to develop overly enlarged and thickened hearts, says Theodore Abraham, M.D., an associate professor at the Johns Hopkins University School of Medicine and its Heart and Vascular Institute. In some instances, top athletes have died from heart conditions while seemingly in peak physical form, something that can hide warning signs and allow many cases to go undiagnosed.

In a study to be presented Nov. 15 at the American Heart Association`s (AHA) annual Scientific Sessions in Orlando, Abraham and colleagues analyzed data from 134 top Maryland high school athletes that they screened at the 2008 track and field state championships. The researchers were looking for life-threatening cardiac abnormalities, such as hypertrophic cardiomyopathies. Doctors took a medical history, took weight and blood pressure measurements and listened for unusual heartbeats or murmurs. They also conducted an echocardiogram — a cardiac ultrasound, or ECHO — to measure heart size and pumping function and to check for faulty heart valves; and an electrocardiogram, or EKG, to assess the heart`s electrical rhythms.

None of the student athletes were found to have life-threatening heart defects, but abnormal findings were discovered in 36 athletes. Twenty-two of those abnormalities were found by EKG alone, nine by ECHO alone and five were picked up on both tests. Those with abnormalities — which included 19 with high blood pressure, 29 with elevated blood pressure in need of future monitoring, and five with low blood pressure readings — were referred for follow-up to their doctors.

"If you are going to screen, it has to be comprehensive," says Abraham, who spearheads the annual "Heart Hype" screening program run by Johns Hopkins, and designed to serve as a national model for other leading academic medical centers. Some screening programs just include EKGs and not ECHOs. "An EKG does show you a lot," he says, "but it doesn`t tell you the whole story. The advantage of a comprehensive screening is that it is holistic, rather than being pinpoint."

For example, if a doctor were screening for prostate cancer, "he wouldn`t ignore a large tumor on your head," Abraham says.

Lead study investigator Aurelio Pinheiro, M.D., a postdoctoral research fellow at Hopkins, says he wasn`t surprised that he and his colleagues didn`t find anyone with a life-threatening heart abnormality since it is estimated that one in 500 Americans has undiagnosed hypertrophic cardiomyopathy and the Hopkins team screened fewer than that. Still, he says, the screening program is not just designed to prevent deaths from sudden cardiac arrest, but also to raise awareness of the risks to young athletes.

Less pressing — but still serious — medical conditions also were found by the researchers, notably high blood pressure, which in teenagers, Pinheiro says, can lead to heart failure or kidney disease 10 or 15 years in the future if left untreated. He adds that two of the track stars examined were obese, which can lead to other health risks in the future if not taken care of.

During this year`s screening program, doctors found a serious undiagnosed valve disease in one athlete and found another suffering from a condition they didn`t know about that could likely mean a heart transplant in the future. The students had no symptoms.

In some nations, programs to screen teenage athletes and non-athletes for possible heart problems have been routine for years. In 2004, the International Olympic Committee recommended that all athletes be EKG-tested every two years for potential heart abnormalities, regardless of whether they have a history of cardiac trouble. The U.S. Olympic Committee offers voluntary cardiac screening.

Other screening programs have used just EKG and not ECHO, which the study suggests will miss some heart problems.

Some argue that doing expensive diagnostic tests such as the EKG and ECHO are not worth the costs since sudden cardiac death in young people is relatively rare and mass screenings are unlikely to turn up a large number of teens in immediate danger.

Abraham disagrees. "What is the price for a single life?" he asks. "We`re counting the costs upfront. We`re not counting the savings on the downstream end."

"They`re still teenagers. They think and feel like they`re at the top of the world," Abraham says. "Athletes and other teens should let someone know how they are feeling, especially if they have had chest pains, shortness of breath with activity or have fainted. This could save their life."

The other Johns Hopkins researchers involved in the study are Daniel Bernard; Veronica L. Dimaano; Saman Nazarian, M.D.; Richard George, M.D.; Reid Thompson, M.D.; and Joel Brenner, M.D. Deepti Bhandare, M.D., and Luis Afonso, M.D., both at Wayne State University in Detroit, were also involved.

A dangerous level of carbon dioxide and methane gas haunts Lake Kivu, the freshwater lake system bordering Rwanda and the Republic of Congo.

Scientists can`t say for sure if the volatile mixture at the bottom of the lake will remain still for another 1,000 years or someday explode without warning. In a region prone to volcanic and seismic activity, the fragility of Lake Kivu is a serious matter. Compounding the precarious situation is the presence of approximately 2 million people, many of them refugees, living along the north end of the lake.

An international group of researchers will meet Jan. 13-15 in Gisenyi, Rwanda, to grapple with the problem of Lake Kivu. A grant from the National Science Foundation won by Rochester Institute of Technology will fund the travel and lodging for 18 scientists from the United States to attend the three-day workshop. Anthony Vodacek, conference organizer and associate professor at RIT`s Chester F. Carlson Center for Imaging Science, is working closely with the Rwandan Ministry of Education to organize the meeting.

"Rwandan universities suffered greatly in the 1994 genocide and there are few Rwandan scientists performing significant work on the lake or within the rift system," Vodacek notes. "We will work with the government to identify interested researchers."

Vodacek is convening the workshop with Cindy Ebinger, an expert in East African Rift tectonics at the University of Rochester, and Robert Hecky, an expert in limnology — the study of lake systems — at University of Minnesota-Duluth. Core samples Hecky took in the 1970s initially brought the safety of Lake Kivu under question.

Addressing the lake as a whole system is a new concept for the workshop participants, who will bring their expertise in volcanology, tectonics and limnology to the problem. Vodacek`s goal is to prioritize research activities and improve communication between the North American, European and African collaborators.

"Most scientists are fairly in agreement that the lake is pretty stable; it`s not as if its going to come bursting out tomorrow," Vodacek says. "But in such a tectonically and volcanically active area, you can`t tell what`s going to happen."

One of the problems with Lake Kivu is that the 1,600-foot deep lake never breathes. The tropical climate helps stagnate the layers of the lake, which never mix or turn over. In contrast, fluctuating temperatures in colder climates help circulate lake water and prevent gas build up. Lake Kivu is different from both temperate and other tropical lakes because warm saline springs, arising from ground water percolating through the hot fractured lava and ash, further stabilize the lake. Scientists at the workshop will consider how these spring inputs may vary over time under changing climates and volcanic activity.

A number of catalysts could destabilize the gas resting at the bottom of Lake Kivu. It could be an earthquake, a volcanic explosion, a landslide or even the methane mining that has recently united Rwandan and Congolese interests.

Close calls occurred in 2008 when an earthquake occurred near the lake and in 2002 when a volcanic eruption destroyed parts of Goma in the Democratic Republic of Congo, only 11 miles north of Lake Kivu. Although scientists were alarmed, neither event sufficiently disturbed the gas.

Vodacek likens the contained pressure in the lake to a bottle of carbonated soda or champagne. "In the lake, you have the carbon dioxide on the bottom and 300 meters of water on top of that, which is the cap," he says. "That`s the pressure that holds it. The gas is dissolved in water."

When the cap is removed, bubbles form and rise to the surface. More bubbles form and create a column that drags the water and the gas up to the surface in a chain reaction.

"The question is, and what`s really unknown, is how explosive is that?" Vodacek says.

Through his own research Vodacek plans to simulate the circulation of Lake Kivu. Modeling the circulation patterns above the layers of carbon dioxide and methane will help determine the energy required to disrupt the gas and cause Lake Kivu to explode.

Structural biologists at the University of Pittsburgh School of Medicine have described the architecture of the complex of protein units that make up the coat surrounding the HIV genome and identified in it a "seam" of functional importance that previously went unrecognized. Those findings, reported today in Cell, could point the way to new treatments for blocking HIV infection.

The researchers used a combination of nuclear magnetic resonance and cryoEM, which are standard structural biology tools, to see both the overall shape and the atomic details of capsid protein (CA) assembly. It takes about 1,500 copies of CA to make the coat, or capsid, that surrounds the genome of the AIDS virus.

"This strategy allowed us to see both the forest and the trees," explained study co-author Peijung Zhang, Ph.D., assistant professor in the Department of Structural Biology, Pitt School of Medicine. "Knowing what the CA protein looks like and how the capsid is built will allow scientists to rationally design therapeutic compounds that interfere with assembly of the protein and affect its function."

Capsid proteins, and particularly the interfaces or seams where one connects to another, are very important for assembling and disassembling the HIV coat, said senior author Angela Gronenborn, Ph.D., chair, Department of Structural Biology, and director, University of Pittsburgh Center for HIV Protein Interactions. The study indicates that these seams provide the flexibility to dismantle the coat efficiently after viral entry into the host and to put it back together when new viruses emerge from the cell.

"Our lab experiments show that if we replace a few of the pivotal stitches in the seam by mutation, the resulting viruses are less infectious or even non-infectious," Dr. Gronenborn said. "The capsid, and therefore the virus, can no longer function properly."

Study co-authors include In-Ja L. Byeon, Ph.D., Xin Meng, Ph.D., Jinwon Jung, Ph.D., Gongpu Zhao, Ph.D., Jinwoo Ahn, Ph.D., and Jason Concel, all of the Department of Structural Biology, Pitt School of Medicine; and Ruifeng Yang, Ph.D., Jiong Shi, and Christopher Aiken, Ph.D., all of the Department of Microbiology and Immunology, Vanderbilt University School of Medicine.

The research was funded by the National Institutes of Health.

Can the mere thought of your loved one reduce your pain? Yes, according to a new study by UCLA psychologists that underscores the importance of social relationships and staying socially connected.

The study, which asked whether simply looking at a photograph of your significant other can reduce pain, involved 25 women, mostly UCLA students, who had boyfriends with whom they had been in a good relationship for more than six months.

The women received moderately painful heat stimuli to their forearms while they went through a number of different conditions. In one set of conditions, they viewed photographs of their boyfriend, a stranger and a chair.

"When the women were just looking at pictures of their partner, they actually reported less pain to the heat stimuli than when they were looking at pictures of an object or pictures of a stranger," said study co-author Naomi Eisenberger, assistant professor of psychology and director of UCLA`s Social and Affective Neuroscience Laboratory. "Thus, the mere reminder of one`s partner through a simple photograph was capable of reducing pain."

"This changes our notion of how social support influences people," she added. "Typically, we think that in order for social support to make us feel good, it has to be the kind of support that is very responsive to our emotional needs. Here, however, we are seeing that just a photo of one`s significant other can have the same effect."

In another set of conditions, each woman held the hand of her boyfriend, the hand of a male stranger and a squeeze ball. The study found that when women were holding their boyfriends` hands, they reported less physical pain than when they were holding a stranger`s hand or a ball while receiving the same amount of heat stimulation.

"This study demonstrates how much of an impact our social ties can have on our experience and fits with other work emphasizing the importance of social support for physical and mental health," Eisenberger said.

One practical piece of advice the authors give is that the next time you are going through a stressful or painful experience, if you cannot bring a loved one with you, a photo may do.

The study appears in the November 2009 issue of the journal Psychological Science.

Co-authors are Sarah Master, who earned her Ph.D. in psychology from UCLA; Shelley E. Taylor, UCLA distinguished professor of psychology; Bruce Naliboff, a clinical professor of psychiatry and biobehavioral sciences at the Semel Institute for Neuroscience and Human Behavior at UCLA; David Shirinyan, a postdoctoral scholar at the Semel Institute; and Matthew D. Lieberman, UCLA professor of psychology.