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Hybrid Solar System Makes Rooftop Hydrogen

While roofs across the world sport photovoltaic solar panels to convert sunlight into electricity, a Duke University engineer believes a novel hybrid system can wring even more useful energy out of the sun's rays.

This is the hybrid system schematic. (Credit: Nico Hotz)

Instead of systems based on standard solar panels, Duke engineer Nico Hotz proposes a hybrid option in which sunlight heats a combination of water and methanol in a maze of glass tubes on a rooftop. After two catalytic reactions, the system produces hydrogen much more efficiently than current technology without significant impurities. The resulting hydrogen can be stored and used on demand in fuel cells.

For his analysis, Hotz compared the hybrid system to three different technologies in terms of their exergetic performance. Exergy is a way of describing how much of a given quantity of energy can theoretically be converted to useful work.

"The hybrid system achieved exergetic efficiencies of 28.5 percent in the summer and 18.5 percent in the winter, compared to 5 to 15 percent for the conventional systems in the summer, and 2.5 to 5 percent in the winter," said Hotz, assistant professor of mechanical engineering and materials science at Duke's Pratt School of Engineering.

The paper describing the results of Hotz's analysis was named the top paper during the ASME Energy Sustainability Fuel Cell 2011 conference in Washington, D.C. Hotz recently joined the Duke faculty after completing post-graduate work at the University of California-Berkeley, where he analyzed a model of the new system. He is currently constructing one of the systems at Duke to test whether or not the theoretical efficiencies are born out experimentally.

Hotz's comparisons took place during the months of July and February in order to measure each system's performance during summer and winter months.

Like other solar-based systems, the hybrid system begins with the collection of sunlight. Then things get different. While the hybrid device might look like a traditional solar collector from the distance, it is actually a series of copper tubes coated with a thin layer of aluminum and aluminum oxide and partly filled with catalytic nanoparticles. A combination of water and methanol flows through the tubes, which are sealed in a vacuum.

"This set-up allows up to 95 percent of the sunlight to be absorbed with very little being lost as heat to the surroundings," Hotz said. "This is crucial because it permits us to achieve temperatures of well over 200 degrees Celsius within the tubes. By comparison, a standard solar collector can only heat water between 60 and 70 degrees Celsius."

Once the evaporated liquid achieves these higher temperatures, tiny amounts of a catalyst are added, which produces hydrogen. This combination of high temperature and added catalysts produces hydrogen very efficiently, Hotz said. The resulting hydrogen can then be immediately directed to a fuel cell to provide electricity to a building during the day, or compressed and stored in a tank to provide power later.

The three systems examined in the analysis were the standard photovoltaic cell which converts sunlight directly into electricity to then split water electrolytically into hydrogen and oxygen; a photocatalytic system producing hydrogen similar to Hotz's system, but simpler and not mature yet; and a system in which photovoltaic cells turn sunlight into electricity which is then stored in different types of batteries (with lithium ion being the most efficient).

"We performed a cost analysis and found that the hybrid solar-methanol is the least expensive solution, considering the total installation costs of $7,900 if designed to fulfill the requirements in summer, although this is still much more expensive than a conventional fossil fuel-fed generator," Hotz said.

Costs and efficiencies of systems can vary widely depending on location -- since the roof-mounted collectors that could provide all the building's needs in summer might not be enough for winter. A rooftop system large enough to supply all of a winter's electrical needs would produce more energy than needed in summer, so the owner could decide to shut down portions of the rooftop structure or, if possible, sell excess energy back to the grid.

"The installation costs per year including the fuel costs, and the price per amount of electricity produced, however showed that the (hybrid) solar scenarios can compete with the fossil fuel-based system to some degree," Hotz said. 'In summer, the first and third scenarios, as well as the hybrid system, are cheaper than a propane- or diesel-combusting generator."

This could be an important consideration, especially if a structure is to be located in a remote area where traditional forms of energy would be too difficult or expensive to obtain.

Hotz's research was supported by the Swiss National Science Fund. Joining him in the study were UC-Berkeley's Heng Pan and Costas Grigoropoulos, as well as Seung H. Ko of the Korea Advanced Institute of Science and Technology, Daejon.

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Polar Dinosaur Tracks Open New Trail to Past

Paleontologists have discovered a group of more than 20 polar dinosaur tracks on the coast of Victoria, Australia, offering a rare glimpse into animal behavior during the last period of pronounced global warming, about 105 million years ago.

Photo of the tracks. (Credit: Anthony Martin)

The discovery, reported in the journalAlcheringa, is the largest and best collection of polar dinosaur tracks ever found in the Southern Hemisphere.

"These tracks provide us with a direct indicator of how these dinosaurs were interacting with the polar ecosystems, during an important time in geological history," says Emory paleontologist Anthony Martin, who led the research. Martin is an expert in trace fossils, which include tracks, trails, burrows, cocoons and nests.

The three-toed tracks are preserved on two sandstone blocks from the Early Cretaceous Period. They appear to belong to three different sizes of small theropods -- a group of bipedal, mostly carnivorous dinosaurs whose descendants include modern birds. Photos of the tracks, above and below, by Anthony Martin.

The research team also included Thomas Rich, from the Museum Victoria; Michael Hall and Patricia Vickers-Rich, both from the School of Geosciences at Monash University in Victoria; and Gonzalo Vazquez-Prokopec, an ecologist and expert in spatial analysis from Emory's Department of Environmental Studies.

The tracks were found on the rocky shoreline of remote Milanesia Beach, in Otways National Park. This area, west of Melbourne, is known for energetic surf and rugged coastal cliffs, consisting of layers of sediment accumulated over millions of years. Riddled with fractures and pounded by waves and wind, the cliffs occasionally shed large chunks of rock, such as those containing the dinosaur tracks.

One sandstone block has about 15 tracks, including three consecutive footprints made by the smallest of the theropods, estimated to be the size of a chicken. Martin spotted this first known dinosaur trackway of Victoria last June 14, around noon. He was on the lookout, since he had earlier noticed ripple marks and trace fossils of what looked like insect burrows in piles of fallen rock.

"The ripples and burrows indicate a floodplain, which is the most likely area to find polar dinosaur tracks," Martin explains. The second block containing tracks was spotted about three hours later by Greg Denney, a local volunteer who accompanied Martin and Rich on that day's expedition. That block had similar characteristics to the first one, and included eight tracks. The tracks show what appear to be theropods ranging in size from a chicken to a large crane.

"We believe that the two blocks were from the same rock layer, and the same surface, that the dinosaurs were walking on," Martin says.

The small, medium and large tracks may have been made by three different species, Martin says. "They could also belong to two genders and a juvenile of one species -- a little dinosaur family -- but that's purely speculative," he adds.

The Victoria Coast marks the seam where Australia was once joined to Antarctica. During that era, about 115-105 million years ago, the dinosaurs roamed in prolonged polar darkness. Earth's average temperature was 68 degrees Fahrenheit -- just 10 degrees warmer than today -- and the spring thaws would cause torrential flooding in the river valleys.

The dinosaur tracks were probably made during the summer, Martin says. "The ground would have been frozen in the winter, and in order for the waters to subside so that animals could walk across the floodplain, it would have to be later in the season," he explains.

Lower Cretaceous strata of Victoria have yielded the best-documented assemblage of polar dinosaur bones in the world. Few dinosaur tracks, however, have been found.

In the February 2006, Martin found the first known carnivorous dinosaur track in Victoria, at a coastal site known as Dinosaur Dreaming.

In May 2006, during a hike to another remote site near Milanesia Beach, he discovered the first trace fossil of a dinosaur burrow in Australia. That find came on the heels of Martin's co-discovery of the first known dinosaur burrow and burrowing dinosaur, in Montana. The two discoveries suggest that burrowing behaviors were shared by dinosaurs of different species, in different hemispheres, and spanned millions of years during the Cretaceous Period.

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New Eruption Discovered at Undersea Volcano, After Successfully Forecasting the Event

A team of scientists just discovered a new eruption of Axial Seamount, an undersea volcano located about 250 miles off the Oregon coast -- and one of the most active and intensely studied seamounts in the world.

The manipulator arm of the ROV Jason prepares to sample the new lava flow that erupted in April 2011 at Axial Seamount, located off the Oregon coast. (Credit: Photo courtesy of Bill Chadwick, Oregon State University; Copyright Woods Hole Oceanographic Institution)

What makes the event so intriguing is that the scientists had forecast the eruption starting five years ago -- the first successful forecast of an undersea volcano.

Bill Chadwick, an Oregon State University geologist, and Scott Nooner, of Columbia University, have been monitoring Axial Seamount for more than a decade, and in 2006 published a paper in the Journal of Volcanology and Geothermal Research in which they forecast that Axial would erupt before the year 2014. Their forecast was based on a series of seafloor pressure measurements that indicated the volcano was inflating.

"Volcanoes are notoriously difficult to forecast and much less is known about undersea volcanoes than those on land, so the ability to monitor Axial Seamount, and determine that it was on a path toward an impending eruption is pretty exciting," said Chadwick, who was chief scientist on the recent expedition, which was jointly funded by the National Oceanic and Atmospheric Administration and the National Science Foundation.

Axial last erupted in 1998 and Chadwick, Nooner and colleagues have monitored it ever since. They used precise bottom pressure sensors -- the same instruments used to detect tsunamis in the deep ocean -- to measure vertical movements of the floor of the caldera much like scientists would use GPS on land to measure movements of the ground. They discovered that the volcano was gradually inflating at the rate of 15 centimeters (six inches) a year, indicating that magma was rising and accumulating under the volcano summit.

When Axial erupted in 1998, the floor of the caldera suddenly subsided or deflated by 3.2 meters (10.5 feet) as magma was removed from underground to erupt at the surface. The scientists estimated that the volcano would be ready to erupt again when re-inflation pushed the caldera floor back up to its 1998 level.

"Forecasting the eruption of most land volcanoes is normally very difficult at best and the behavior of most is complex and variable," said Nooner, who is affiliated with the Lamont-Doherty Earth Observatory. "We now have evidence, however, that Axial Seamount behaves in a more predictable way than many other volcanoes -- likely due to its robust magma supply coupled with its thin crust, and its location on a mid-ocean ridge spreading center.

"It is now the only volcano on the seafloor whose surface deformation has been continuously monitored throughout an entire eruption cycle," Nooner added.

The discovery of the new eruption came on July 28, when Chadwick, Nooner and University of Washington colleagues Dave Butterfield and Marvin Lilley led an expedition to Axial aboard the R/V Atlantis, operated by the Woods Hole Oceanographic Institution. Using Jason, a remotely operated robotic vehicle (ROV), they discovered a new lava flow on the seafloor that was not present a year ago.

"It's funny," Chadwick said. "When we first arrived on the seafloor, we thought we were in the wrong place because it looked so completely different. We couldn't find our markers or monitoring instruments or other distinctive features on the bottom. Once we figured out that an eruption had happened, we were pretty excited.

"When eruptions like this occur, a huge amount of heat comes out of the seafloor, the chemistry of seafloor hot springs is changed, and pre-existing vent biological communities are destroyed and new ones form," Chadwick added. "Some species are only found right after eruptions, so it is a unique opportunity to study them."

The first Jason ROV dive of the expedition targeted a field of "black smoker" hot springs on the western side of the caldera, beyond the reach of the new lava flows. Butterfield has been tracking the chemistry and microbiology of hot springs around the caldera since the 1998 eruption.

"The hot springs on the west side did not appear to be significantly disturbed, but the seawater within the caldera was much murkier than usual," Butterfield said, "and that meant something unusual was happening. When we saw the 'Snowblower' vents blasting out huge volumes of white floc and cloudy water on the next ROV dive, it was clear that the after-effects of the eruption were still going strong. This increased output seems to be associated with cooling of the lava flows and may last for a few months or up to a year."

The scientists will examine the chemistry of the vent water and work with Julie Huber of the Marine Biological Laboratory to analyze DNA and RNA of the microbes in the samples.

The scientists recovered seafloor instruments, including two bottom pressure recorders and two ocean-bottom hydrophones, which showed that the eruption took place on April 6 of this year. A third hydrophone was found buried in the new lava flows.

"So far, it is hard to tell the full scope of the eruption because we discovered it near the end of the expedition," said Chadwick, who works out of OSU's Hatfield Marine Science Center in Newport. "But it looks like it might be at least three times bigger than the 1998 eruption."

The lava flow from the 2011 eruptions was at least two kilometers (1.2 miles) wide, the scientists noted.

"Five years ago, these scientists forecast this eruption, which has resulted in millions of square meters of new lava flows on the seafloor," said Barbara Ransom, program director in the National Science Foundation's Division of Ocean Sciences. "The technological advances that allow this research to happen will lead to a new understanding of submarine volcanoes, and of any related hazards."

The bottom-anchored instruments documented hundreds of tiny earthquakes during the volcanic eruption, but land-based seismic monitors and the Sound Surveillance System (SOSUS) hydrophone array operated by the U.S. Navy only detected a handful of them on the day of the eruption because many components of the hydrophone system are offline.

"Because the earthquakes detected back in April at a distance from the volcano were so few and relatively small, we did not believe there was an eruption," said Bob Dziak, an OSU marine geologist who monitors the SOSUS array. "That is why discovering the eruption at sea last week was such a surprise." Both Dziak and Chadwick are affiliated with the Cooperative Institute for Marine Resource Studies -- a joint NOAA/Oregon State University institute.

This latest Axial eruption caused the caldera floor to subside by more than two meters (six feet). The scientists will be measuring the rate of magma inflation over the next few years to see if they can successfully forecast the next event.

"The acid test in science -- whether or not you understand a process in nature -- is to try to predict what will happen based on your observations," Chadwick said. "We have done this and it is extremely satisfying that we were successful. Now we can build on that knowledge and look to apply it to other undersea volcanoes -- and perhaps even volcanoes on land."

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Study Builds On Plausible Scenario for Origin of Life On Earth

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.

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)

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.

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.

"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.

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

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).

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)

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.

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.

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.

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Deep Recycling in Earth Faster Than Thought

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.

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.)

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 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.

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.

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Multiple Sclerosis Research Doubles Number of Genes Associated With the Disease, Increasing the Number to Over 50

Dr. John Rioux, researcher at the Montreal Heart Institute, Associate Professor of Medicine at the Université de Montréal and original co-founder of the International Multiple Sclerosis Genetics Consortium is one of the scientists who have identified 29 new genetic variants linked to multiple sclerosis, providing key insights into the biology of a very debilitating neurological disease. Many of the genes implicated in the study are relevant to the immune system, shedding light onto the immunological pathways that underlie the development of multiple sclerosis.

Scientists have identified 29 new genetic variants linked to multiple sclerosis, providing key insights into the biology of a very debilitating neurological disease. Many of the genes ¬implicated in the study are relevant to the immune system, shedding light onto the immunological pathways that underlie the development of multiple sclerosis. (Credit: © Attila Németh / Fotolia)

The research, involving an international team of investigators led by the Universities of Cambridge and Oxford, and funded by the Wellcome Trust, was published August 10 in the journal Nature. This is the largest MS genetics study ever undertaken and includes contributions from almost 250 researchers as members of the International Multiple Sclerosis Genetics Consortium and the Wellcome Trust Case Control Consortium.

Multiple sclerosis is one of the most common neurological conditions among young adults, affecting around 2.5 million individuals worldwide. The disease results from damage to nerve fibres and their protective insulation, the myelin sheath, in the brain and spinal cord. The affected pathways -- responsible in health for everyday activities such as seeing, walking, feeling, thinking and controlling the bowel and bladder -- are prevented from 'firing' properly and eventually are destroyed. The new findings focus attention on the pivotal role of the immune system in causing the damage and help to explain the nature of the immune attack on the brain and spinal cord.

In this multi-population study, researchers studied the DNA from 9,772 individuals with multiple sclerosis and 17,376 unrelated healthy controls. They were able to confirm 23 previously known genetic associations and identified a further 29 new genetic variants (and an additional five that are strongly suspected) conferring susceptibility to the disease.

A large number of the genes implicated by these findings play pivotal roles in the workings of the immune system, specifically in the function of T-cells (one type of white blood cell responsible for mounting an immune response against foreign substances in the body but also involved in autoimmunity) as well as the activation of 'interleukins' (chemicals that ensure interactions between different types of immune cell). Interestingly, one third of the genes identified in this research have previously been implicated in playing a role in other autoimmune diseases (such as Crohn's Disease and Type 1 diabetes) indicating that, perhaps as expected, the same general processes occur in more than one type of autoimmune disease.

Previous research has suggested a link between Vitamin D deficiency and an increased risk of multiple sclerosis. Along with the many genes which play a direct role in the immune system, the researchers identified two involved in the metabolism of Vitamin D, providing additional insight into a possible link between genetic and environmental risk factors.

Dr. Alastair Compston from the University of Cambridge who, on behalf of the International Multiple Sclerosis Genetics Consortium, who led the study jointly with Dr. Peter Donnelly from the Wellcome Trust Centre for Human Genetics, University of Oxford, said: "Identifying the basis for genetic susceptibility to any medical condition provides reliable insights into the disease mechanisms. Our research settles a longstanding debate on what happens first in the complex sequence of events that leads to disability in multiple sclerosis. It is now clear that multiple sclerosis is primarily an immunological disease. This has important implications for future treatment strategies."

Dr. Donnelly added: "Our findings highlight the value of large genetic studies in uncovering key biological mechanisms underlying common human diseases. This would simply not have been possible without a large international network of collaborators, and the participation of many thousands of patients suffering from this debilitating disease."

Dr. John Rioux, holder of the Canada Research Chair in Genetics and Genomic Medicine, furthermore stated that "the integration of the genetic information emerging from studies of this and other chronic inflammatory diseases such as Crohn's disease, ulcerative colitis, arthritis and many others is revealing what is shared across these diseases and what is disease-specific. This is but one of the key bits of information emerging from these studies that will guide the research of disease biology for years to come and be the basis for the development of a more personalized approach to medicine."

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Genetically Modified 'Serial Killer' T-Cells Obliterate Tumors in Leukemia Patients

In a cancer treatment breakthrough 20 years in the making, researchers from the University of Pennsylvania's Abramson Cancer Center and Perelman School of Medicine have shown sustained remissions of up to a year among a small group of advanced chronic lymphocytic leukemia (CLL) patients treated with genetically engineered versions of their own T cells. The protocol, which involves removing patients' cells and modifying them in Penn's vaccine production facility, then infusing the new cells back into the patient's body following chemotherapy, provides a tumor-attack roadmap for the treatment of other cancers including those of the lung and ovaries and myeloma and melanoma.

The protocol, which involves removing patients' cells and modifying them in Penn's vaccine production facility, then infusing the new cells back into the patient's body following chemotherapy, provides a tumor-attack roadmap for the treatment of other cancers including those of the lung and ovaries and myeloma and melanoma. (Credit: Image courtesy of University of Pennsylvania School of Medicine)

The findings, published simultaneously in the New England Journal of Medicine and Science Translational Medicine on August 10, are the first demonstration of the use of gene transfer therapy to create "serial killer" T cells aimed at cancerous tumors.

"Within three weeks, the tumors had been blown away, in a way that was much more violent than we ever expected," said senior author Carl June, MD, director of Translational Research and a professor of Pathology and Laboratory Medicine in the Abramson Cancer Center, who led the work. "It worked much better than we thought it would."

The results of the pilot trial of three patients are a stark contrast to existing therapies for CLL. The patients involved in the new study had few other treatment options. The only potential curative therapy would have involved a bone marrow transplant, a procedure which requires a lengthy hospitalization and carries at least a 20 percent mortality risk -- and even then offers only about a 50 percent chance of a cure, at best.

"Most of what I do is treat patients with no other options, with a very, very risky therapy with the intent to cure them," says co-principal investigator David Porter, MD, professor of Medicine and director of Blood and Marrow Transplantation. "This approach has the potential to do the same thing, but in a safer manner."

Secret Ingredients

June thinks there were several "secret ingredients" that made the difference between the lackluster results that have been seen in previous trials with modified T cells and the remarkable responses seen in the current trial. The details of the new cancer immunotherapy are detailed in Science Translational Medicine.

After removing the patients' cells, the team reprogrammed them to attack tumor cells by genetically modifying them using a lentivirus vector. The vector encodes an antibody-like protein, called a chimeric antigen receptor (CAR), which is expressed on the surface of the T cells and designed to bind to a protein called CD19.

Once the T cells start expressing the CAR, they focus all of their killing activity on cells that express CD19, which includes CLL tumor cells and normal B cells. All of the other cells in the patient that do not express CD19 are ignored by the modified T cells, which limits side effects typically experienced during standard therapies.

The team engineered a signaling molecule into the part of the CAR that resides inside the cell. When it binds to CD19, initiating the cancer-cell death, it also tells the cell to produce cytokines that trigger other T cells to multiply -- building a bigger and bigger army until all the target cells in the tumor are destroyed.

Serial Killers

"We saw at least a 1000-fold increase in the number of modified T cells in each of the patients. Drugs don't do that," June says. "In addition to an extensive capacity for self-replication, the infused T cells are serial killers. On average, each infused T cell led to the killing of thousands of tumor cells -- and overall, destroyed at least two pounds of tumor in each patient."

The importance of the T cell self-replication is illustrated in theNew England Journal of Medicine paper, which describes the response of one patient, a 64-year old man. Prior to his T cell treatment, his blood and marrow were replete with tumor cells. For the first two weeks after treatment, nothing seemed to change. Then on day 14, the patient began experiencing chills, nausea, and increasing fever, among other symptoms. Tests during that time showed an enormous increase in the number of T cells in his blood that led to a tumor lysis syndrome, which occurs when a large number of cancer cells die all at once.

By day 28, the patient had recovered from the tumor lysis syndrome -- and his blood and marrow showed no evidence of leukemia.

"This massive killing of tumor is a direct proof of principle of the concept," Porter says.

The Penn team pioneered the use of the HIV-derived vector in a clinical trial in 2003 in which they treated HIV patients with an antisense version of the virus. That trial demonstrated the safety of the lentiviral vector used in the present work.

The cell culture methods used in this trial reawaken T cells that have been suppressed by the leukemia and stimulate the generation of so-called "memory" T cells, which the team hopes will provide ongoing protection against recurrence. Although long-term viability of the treatment is unknown, the doctors have found evidence that months after infusion, the new cells had multiplied and were capable of continuing their seek-and-destroy mission against cancerous cells throughout the patients' bodies.

Moving forward, the team plans to test the same CD19 CAR construct in patients with other types of CD19-positive tumors, including non-Hodgkin's lymphoma and acute lymphocytic leukemia. They also plan to study the approach in pediatric leukemia patients who have failed standard therapy. Additionally, the team has engineered a CAR vector that binds to mesothelin, a protein expressed on the surface of mesothelioma cancer cells, as well as on ovarian and pancreatic cancer cells.

In addition to June and Porter, co-authors on the NEJM paper include Bruce Levine, Michael Kalos, and Adam Bagg, all from Penn Medicine. Michael Kalos and Bruce Levine are co-first authors on the Science Translational Medicine paper. Other co-authors include June, Porter, Sharyn Katz and Adam Bagg from Penn and Stephan Grupp the Children's Hospital of Philadelphia.

The work was supported by the Alliance for Cancer Gene Therapy, a foundation started by Penn graduates, Barbara and Edward Netter, to promote gene therapy research to treat cancer, and the Leukemia & Lymphoma Society.

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Engineers Reverse E. Coli Metabolism for Quick Production of Fuels, Chemicals

In a biotechnological tour de force, Rice University engineering researchers this week unveiled a new method for rapidly converting simple glucose into biofuels and petrochemical substitutes. In a paper published online in Nature, Rice's team described how it reversed one of the most efficient of all metabolic pathways -- the beta oxidation cycle -- to engineer bacteria that produce biofuel at a breakneck pace.

Just how fast are Rice's single-celled chemical factories? On a cell-per-cell basis, the bacteria produced the butanol, a biofuel that can be substituted for gasoline in most engines, about 10 times faster than any previously reported organism.

"That's really not even a fair comparison because the other organisms used an expensive, enriched feedstock, and we used the cheapest thing you can imagine, just glucose and mineral salts," said Ramon Gonzalez, associate professor of chemical and biomolecular engineering at Rice and lead co-author of the Nature study.

Gonzalez's laboratory is in a race with hundreds of labs around the world to find green methods for producing chemicals like butanol that have historically come from petroleum.

"We call these 'drop-in' fuels and chemicals, because their structure and properties are very similar, sometimes identical, to petroleum-based products," he said. "That means they can be 'dropped in,' or substituted, for products that are produced today by the petrochemical industry."

Butanol is a relatively short molecule, with a backbone of just four carbon atoms. Molecules with longer carbon chains have been even more troublesome for biotech producers to make, particularly molecules with chains of 10 or more carbon atoms. Gonzalez said that's partly because researchers have focused on ramping up the natural metabolic processes that cells use to build long-chain fatty acids. Gonzalez and students Clementina Dellomonaco, James Clomburg and Elliot Miller took a completely different approach.

"Rather than going with the process nature uses to build fatty acids, we reversed the process that it uses to break them apart," Gonzalez said. "It's definitely unconventional, but it makes sense because the routes nature has selected to build fatty acids are very inefficient compared with the reversal of the route it uses to break them apart."

The beta oxidation process is one of biology's most fundamental, Gonzalez said. Species ranging from single-celled bacteria to human beings use beta oxidation to break down fatty acids and generate energy.

In the Nature study, Gonzalez's team reversed the beta oxidation cycle by selectively manipulating about a dozen genes in the bacteria Escherichia coli. They also showed that selective manipulations of particular genes could be used to produce fatty acids of particular lengths, including long-chain molecules like stearic acid and palmitic acid, which have chains of more than a dozen carbon atoms.

"This is not a one-trick pony," Gonzalez said. "We can make many kinds of specialized molecules for many different markets. We can also do this in any organism. Some producers prefer to use industrial organisms other than E. coli, like algae or yeast. That's another advantage of using reverse-beta oxidation, because the pathway is present in almost every organism."

The research was funded by Rice University.

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Narcissists Look Like Good Leaders, but They Aren't

ScienceDaily (Aug. 10, 2011) — 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 ofPsychological 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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Meteorites contain chemicals linked to life

Meteorites contain chemicals linked to life

Space rocks could have delivered DNA building blocks to Earth

By Alexandra Witze

Web edition : Wednesday, August 10th, 2011

  Text Size

ENLARGE

HINTS OF LIFEChemists have found that this meteorite, found in Antarctica and dubbed Lonewolf Nunataks 94102, contains nucleobases, the building blocks of DNA. The nucleobases probably originated in space, the scientists say.M. Callahan/NASA GSFC

Scientists have discovered life-related chemicals in nearly a dozen meteorites, the strongest evidence yet that space rocks contain the building blocks of DNA and could have delivered them to Earth.
Several of the chemicals are extremely rare on Earth, suggesting they really are from outer space instead of being just local contamination. “Everything points to these being indigenous to the meteorites,” says Michael Callahan, an analytical chemist at NASA’s Goddard Space Flight Center in Greenbelt, Md.
He and his colleagues published the findings online the week of August 8 in Proceedings of the National Academy of Sciences.
Researchers have spotted other extraterrestrial biological molecules in meteorites before, including amino acids, the building blocks of proteins. The new study looked instead at nucleobases, ring-shaped compounds used to store information in RNA and DNA molecules, which carry life’s genetic blueprints. Nucleobases are at least as important to life as amino acids, Callahan says, and, until now, no one had found nucleobases in meteorites that couldn’t potentially have been contaminants from Earth.
To tackle the question, Callahan’s team probed the chemistry of 12 meteorites, including nine that had been scooped up on the Antarctic ice sheet. Eleven contained at least one nucleobase, adenine, that is common on Earth. Others were more exotic. Two of the meteorites, known as Murchison and Lonewolf Nunataks 94102, turned out to host a wide variety of nucleobases, including three that are rare on Earth. These rare nucleobases are from a class called purines.
The researchers carefully analyzed the Antarctic ice, earthly soil and other control samples that could show whether terrestrial contamination was a problem. The team didn’t find the nucleobases anywhere but in the meteorites.
To figure out how the chemicals got there, the scientists mixed hydrogen cyanide, ammonia and water — common meteorite ingredients — in the laboratory. The resulting chemical reactions yielded the same kinds of nucleobases seen in the meteorites.
Callahan now wants to see whether he can find nucleobases in other space rocks.
The new study significantly bolsters the evidence that nucleobases can form in places other than Earth, says Alan Schwartz, a chemist at Radboud University Nijmegen in the Netherlands. Schwartz has looked for purines before in the Murchison meteorite, and the new study reported much lower levels of those chemicals than he did — suggesting that nucleobases, where they exist, might be spread patchily through the rock.
A second paper appearing online in Proceedings of the National Academy of Sciences the same week looks at the biological contents of meteorites from a different angle. A team led by George Cooper of NASA’s Ames Research Center in Moffett Field, Calif., discovered chemicals such as pyruvic acid and citric acid in several meteorites, including Murchison. On Earth, these chemicals are key players in the citric acid cycle, which cells need to respire and survive.
The papers both suggest that space rocks contain more of life’s ingredients than once thought.

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EDISON'S ANTI-GRAVITY UNDERWEAR AND OTHER WONDERS

While trolling through my RSS feeds last week, I came across a delightful blog post by John Ptak, who has a penchant for quirky historical oddities -- in this case, an 1879 issue of The London Punch crediting US inventor Thomas Edison with the invention of antigravity undergarments.

It's worth perusing just for the imaginative illustrations (see above), with museum goers floating aloft to view paintings hung near the ceiling, and parents tethering their levitating offspring to bicycles for an afternoon jaunt.

WATCH VIDEO: Dark energy seems to have an antigravity effect on the entire Universe.

SLIDE SHOW: Stupid Inventions of the Past

It wasn't real, of course, but at the time, Edison was just coming into his fame, and seemed like he could achieve any number of marvels previously thought impossible. He was even featured in an early science fiction novel by Garrett P. Serviss, Edison's Conquest of Mars (1898), which introduced numerous tropes of science fiction: alien abductions, spacesuits, and disintegrator rays, for example.

While that novel didn't feature antigravity underwear, HG Wells invented a fictional substance called "cavorite" for The First Men in the Moon, capable of blocking gravity. The concept is that, because cavorite shields the air above it from gravity, there is more air pressure below, shooting the lighter air outward. The material is used to build a spaceship and travel to the moon, but who says it couldn't also be used for underwear?

SEE ALSO: Henrietta Swan Leavitt Comes to Life on Stage

What about real-life antigravity schemes? Many of the young boys who devoured those early science fiction novels grew up to be fascinated by futuristic technologies. Some of them spent decades laboring over prototype inventions that never quite seemed to work. Whether they were crackpots or visionaries depends on who you ask, but here are five of the best known proponents of antigravity.

1. Roger Babson. Roger Babson was a successful businessman who went on to become the founder of Babson College. In 1948 he also founded the Gravity Research Foundation, devoted entirely to studying ways to reduce the effects of gravity -- or, at least, gaining a better understanding of this mysterious physical force.

One Foundation trustee, Agnew Bahnson, created the sister Insitute for Field Physics at the University of North Carolina, Chapel Hill, for the study of gravitation. When Babson died in 1967, the Foundation dissolved, although there is still an annual essay contest for groundbreaking insights into gravitational phenomena. Among the past winners is astrophysicist George Smoot, who went on to win the 2006 Nobel Prize in Physics.

SLIDE SHOW: Inventors Killed By Their Own Inventions

2. Thomas Townsend Brown. In a chain of events straight out of The X-Files, in 1955, a man named Thomas Townsend Browntraveled first to England, then to France, to work on a top-secret research project called Projet Mongolfier. Brown's previous work had been in high-voltage experiments, and 30 years before, he had developed a device he called a "gravitator." He claimed it produced anti-gravity effects simply by applying high voltages to materials with high dielectric constants.

He based the concept on his earlier work investigating the Biefeld-Brown effect, also known as electrogravitics, whichWikipedia describes as "an electrical effect that produces an ionic wind that transfers its momentum to surrounding neutral particles" -- in other words, it produces a kind of electric propulsion.

Brown endured his share of ridicule for his ideas, but by the 1950s, several aerospace firms were interested in studying this effect as part of a broad gravity propulsion research program in the US that lasted from 1955 to 1974. It is still the basis for so-called ionocraft, "lifters," or, more recently, EHD (electrohydrodynamics) thrusters. Numerous patents were issued during the 1960s -- several to Brown himself.

Brown's reputation took a beating in part because he believed the Biefeld-Brown effect could explain the maneuvering of UFOs. Yes, he was a diehard ufologist, and co-founder of the National Investigations Committee on Aerial Phenomena, although he resigned almost immediately after it was established. His work with Project Mongolfier no doubt added to his aura of mystique, although it seems his research may have ultimately lost support when it failed to produce the desired results.

SEE ALSO: Was Roswell 'Flying Saucer' Mystery a Soviet Plot?

3. Henry William Wallace. In the early 1970s, several patents for antigravity-type devices were granted to Henry William Wallace, an engineer at GE Aerospace in Pennsylvania.

He figured if you could build the device out of just the right materials (say disks of brass), and then spin it rapidly, it would generate its own energy field. Wallace dubbed it a "Kinemassic Forcefield." And if you could get that force field to undulate in turn, you could "neutralize" gravity. In short, it would create an anti-gravity field.

A 1980 article in New Scientist described his invention thusly:

"In one kinemassic machine a pair of wheels of brass alloy, like gyroscopes, are mounted in close-fitting air gaps between massive structural supports formed from steel. The wheels are driven to a high speed of rotation by jets of compressed air or nitrogen. The inventor claims that, at speeds of about 20,000 rpm, polarization of the spin nuclei of the alloyed metal occurs. If one wheel is balanced on a knife edge, it will start to oscillate under the influence of the other. If the spinning wheels are rotated abut another axis, a secondary gravitational field is created which reduces the wheels’ weight. If a sufficiently strong field is created, it can generate localized areas of gravitational shielding and thus provide an effective propulsion force."

4. Eric Laithwaite. Although many dismissed Wallace as a bit of a crank, an electrical engineer at Imperial College, London, named Eric Laithwaite, independently developed his own version of an anti-gravity device along similar lines.

Laithwaite started out working with linear induction motors, then went on to help create one of the first magnetic levitation systems. James Bond fans might recall a scene in The Spy Who Loved Me that featured Laithwaite's system levitating a tray across a table with sufficient speed to decapitate a dummy. (You can see some fascinating video footage of Laithwaite talking about both the maglev work and his work on gyroscopes here.)

Then he became fascinated by gyroscopes after an amateur inventor named Alex Jones showed him a prototype "reactionless propulsion drive." Laithwaite gave a 1974 talk at the Royal Institution in which he insisted that a spinning gyroscope weighs less than a motionless one, and that this could not be accounted for by Newton's laws of motion. Ergo, reactionless propulsion should be possible. His talk was not well-received. Indeed, it is the only time the Royal Institution has declined to publish an invited lecture.

Laithwaite backed off his "Newton was wrong" stance, but still thought a reactionless propulsion system was possible based on the behavior of gyroscopes. His perseverance paid off in 1999 when the US Patent Office granted him Patent # 5860317. But a working prototype never materialized.

5. Eugene (Yevgeny) Podkletnov. One of the more recent proposals for antigravity devices was contained in a paper that appeared in the peer-reviewed journal Physica C in 1992 by Russian engineer Eugene Podkletnov.

Podkletnov claimed that rotating a chilled superconducting disk very quickly would reduce the effects of gravity -- specifically, he reported a slight reduction in weight in any object suspended above the disk. (One of the many cool properties of superconductors is that they repel magnetic fields.)

That first paper didn't attract much notice, perhaps because the observed weight reduction was so tiny (0.3%). But in 1996, a longer paper appeared in theJournal of Physics D, reporting a more significant weight reduction of 2%. Then the Sunday Telegraphgot wind and ran an article proclaiming the achievement of "the world's first antigravity device."

To say the claim was controversial would be an understatement, even though Podkletnov insisted his claim was simply a reduction in gravity's effect -- not blocking it entirely. But it was enough to intrigue NASA sufficiently to embark on its own research program for an "antigravity shield." The research was fraught with problems, and Podkletnov himself proved to be of little help, saying he was "just a ceramics physicist" who had hired others to build the actual device.

In 1997 he retracted his second paper and left his position with the Tampere University of Technology in Finland to return to Moscow. That same year, he claimed to have built a new device capable of generating a "gravity repulsion beam." He envisioned making flying machines that could reflect gravity waves and maneuver like UFOs.

While Podkletnov claimed his work was reproduced by scientists in Toronto and Sheffield, none of them came forward with the results of those purported experiments. So let's just say the physics community remains skeptical about the real-world potential for true antigravity devices. Although antigravity underwear would still be really cool.

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