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Ars Technica: A history of Earth's average temperature over the last 12 000 years was recently created by using a wide range of local direct records and proxies for temperature. Zhengyu Liu of the University of Wisconsin and his colleagues compared that historical data with three climate-model simulations spanning the last 21 000 years. They found that, where the historical data showed a peak and then a brief drop in temperatures before continued increases, the models showed a continual temperature increase, albeit at a slower rate. The models based their simulations on variations in sunlight due to Earth's orbital changes and the known growth in greenhouse gases. A closer examination of the models and data revealed that some of the proxies likely indicated summer temperatures, not yearly averages. Adjusting the models to favor summer temperatures produced a closer fit to the historical data, but significant differences remained. It is likely that adjustments need to be made to both the model and the interpretation of the historical data.
BBC: Microorganisms have been discovered in samples collected from Lake Whillans, a body of liquid water buried some 800 m below the ice in West Antarctica. At those depths, there is little sunlight or organic material. Instead the tiny organisms appear to be fueled by inorganic compounds—such as ammonium, nitrate, and sulphides—found in the rock that makes up the lake bed. To ensure the samples were free of surface contamination, the Whillans Ice Stream Subglacial Access Research Drilling project took extensive precautions, including the use of ultraclean drilling methods. The discovery of life in such a forbidding Earth environment leads scientists to propose that similar life might also be found in the large volumes of liquid water lying beneath the icy crusts of some of the moons of Jupiter and Saturn and possibly other celestial bodies.
FuelFix: Siluria Technologies, based in San Francisco, California, is developing a process for converting methane into gasoline and ethylene. To date, it has received nearly $100 million in venture capital funding. Methane-to-gasoline conversion seemed promising in the 1980s but was abandoned in favor of the Fischer–Tropsch process, which converts a mixture of carbon monoxide and hydrogen into liquid hydrocarbons. Siluria claims to have identified a catalyst that makes its technique more efficient than Fischer–Tropsch. Of the funding the company has received, Siluria announced yesterday that $30 million came from Saudi Aramco, the Saudi Arabian state oil and gas company. Ed Dineen, Siluria's CEO, says that the company hopes to have the process commercialized and a plant running by 2017 or 2018. In the meantime, the company plans to install a demonstration unit in Houston, Texas, later this year.
Nature: Modern humans and Neanderthals probably coexisted for thousands of years, according to a new study published in Nature. Because that overlap occurred some 30 000–50 000 years ago, however, traditional radiocarbon dating techniques have proven unreliable for analyzing the organic remains. After 30 000 years, 98% of the carbon isotope has disappeared and younger carbon has started seeping in. Now Tom Higham of Oxford University and colleagues explain how they expelled the contaminating carbon and used accelerator mass spectrometry to measure the minuscule amounts of radiocarbon left in samples from 40 key archaeological sites across southern Europe. The technique has allowed them to verify that humans and Neanderthals lived contemporaneously for possibly as long as 5000 years. The long overlap would have provided plenty of time for cultural exchange and interbreeding, says Higham.
MIT Technology Review: Wirelessly networked traffic signals include sensors for detecting approaching vehicles, controllers that manage the lights, radios to communicate between intersections, and malfunction management units to reset the system if an error occurs. With official permission, a group of researchers from the University of Michigan led by J. Alex Halderman hacked into a local traffic-light network and discovered three major vulnerabilities, which they report result from a “systemic lack of security consciousness” in the networks’ design. Anyone with a computer that can transmit on the same wireless frequency as the network’s radios could gain complete control of the network, for example. Similar vulnerabilities have been known about for years in other devices as well, such as voting machines. Until hardware producers take security practices more seriously, the potential for damage from malicious or capricious access will continue to increase.
Nature: NASA’s Cassini spacecraft has provided the first measurement of the rate at which dust is falling into Saturn’s rings. During seven years of observations, researchers detected only 140 particles whose trajectories indicate they came from elsewhere in the solar system. That rate is 40 times lower than expected. Because of the current level of dustiness, the rings may be much older than previously estimated. It is possible that the rings formed 4 billion years ago, soon after the planet itself formed. The previously estimated rate of dust collection was so high because it wasn’t known that the amount of dust outside the asteroid belt, where Saturn is located, is much lower than the amount inside, where Earth is located. Based on Cassini‘s data, it appears that most of the detected dust particles came from the Kuiper belt, a collection of frozen bodies outside the orbit of Neptune that includes Pluto and at least two other dwarf planets.
BBC: Lacking claws or adhesive structures, snakes are forced to flex their muscles when climbing trees. Snakes move via what's called concertina locomotion, a strenuous process that requires some parts of the body to grip tightly to a surface while other parts are pulled or pushed in the direction of motion. A new study shows that most snakes, while making a vertical climb, actually hold on much more tightly than they need to. Researchers Greg Byrnes of Siena College in New York and Bruce Jayne of the University of Cincinnati monitored five different snake species as they climbed a special pipe equipped with pressure sensors. The researchers observed that all the snakes exerted more than three times the force necessary to support their own weight. That observation led the researchers to propose that snakes value safety over efficiency.
Voice of America: Because of intense seismic activity around Bardarbunga volcano since mid-August, Iceland’s Meteorological Office is preparing for a possible eruption and all the problems that can ensue. When Iceland’s Eyjafjallajökull volcano erupted in 2010, the event shut down much of Europe’s airspace for almost a week due to ash and smoke, which can reduce visibility and damage aircraft. So Iceland is monitoring the current situation closely. After a weekend of intense earthquake activity around the volcano, the Met Office has raised the aviation color warning code to orange, the fourth level on a five-grade scale. On Iceland itself, area roads have been closed in anticipation of possible flooding because Bardarbunga is located under a glacial ice cap.
Ars Technica: To better study biological networks, such as gene expression, which is essential to the development of living things, researchers have constructed a biochip containing an array of artificial cells. The cells are composed of bundles of DNA assembled on the surface of circular silicon compartments. The DNA was fed nutrients through thin capillaries, which allowed the genes to metabolize. To monitor how that complex process evolves as the cell develops and reacts to environmental changes, the researchers tracked the presence of green fluorescent protein expressed from the DNA. With the biochip, they were able to successfully demonstrate gene expression at the embryonic scale.
Nature: Although the injection of wastewater into the ground by hydraulic fracturing and other drilling projects has been known to cause earthquakes, the quakes tend to induce less shaking than natural quakes of the same magnitude, according to a recent study published in the Bulletin of the Seismological Society of America. One reason may be that the fluids injected into the ground “lubricate geological faults and allow them to slip more smoothly,” according to the paper’s author, Susan Hough of the US Geological Survey. Hough studied both manmade and natural earthquakes and compared the reported magnitude with what people said they felt. However, the finding only holds true for areas more than 10 km from the quake’s epicenter. The research may prompt restrictions on the location of such drilling efforts to keep them away from populated areas.
BBC: Inspired by the color-changing abilities of octopuses and other cephalopods, researchers have been developing a paper-thin flexible sheet composed of 1-mm-square cells containing a temperature-controlled dye. Just as octopus skin has a three-layer design, so, too, does the new material. A grid of photosensors is overlain with a layer of “actuators” that produce a current, which causes the temperature-sensitive pigment in the top layer to change from black to transparent. Although less efficient and having fewer color choices than the animals that inspired it, the new material nevertheless represents a first step toward a new class of material that could find use in the military and any number of other applications.
Houston Press: As the next generation of scientists and engineers interested in space exploration graduates from college, many are taking jobs with private space companies, such as SpaceX, rather than following the traditional route to NASA. In recent years, NASA has been plagued with problems, among them financial insecurity, lack of administrative direction, extensive bureaucracy, and cancellation of several major projects, such as the space shuttle program. As a result, young researchers are increasingly taking jobs with commercial launch companies, which they feel offer more autonomy in seeing projects through from start to finish and greater possibility for future space travel. NASA, however, maintains that space exploration has always depended on collaboration among government, academia, and the commercial sector. And with other nations planning Moon missions, such collaborations may become even more necessary to ensure the US’s place in space.
Christian Science Monitor: Federal wildlife investigators say that as many as 28 000 birds are being killed every year at the BrightSource Energy plant located in the Mojave Desert. The birds get burned by the intense heat from the 300 000 garage-door-sized mirrors that reflect the Sun’s rays onto three 40-story-high boiler towers. Although the US Fish and Wildlife Service has said that such power towers are the most lethal type of construction for wildlife, BrightSource is proposing to build another mirror field and a 75-story tower near the California–Arizona border. As the California Energy Commission considers the proposal, BrightSource is exploring the use of lights, sounds, or other means to divert the birds away from its plants.
New York Times: Because of the ever-increasing amounts of data being generated by the Web, smartphones, and other technologies, data scientists are having to wrangle with the vast output to pare it down and organize it into a usable format. “You spend a lot of your time being a data janitor, before you can get to the cool, sexy things that got you into the field in the first place,” said Matt Mohebbi, a data scientist and cofounder of Iodine, a new health startup. Several companies are writing computer software to automate the data-wrangling process. Among other challenges, the programs must be able to merge many different data formats. In much the same way that spreadsheets revolutionized data analysis in business and finance, machine-learning technology could help free data scientists from the more mundane sorting tasks so they can concentrate on the bigger picture.
New Scientist: Despite decades of research indicating that climate change is occurring, it's been difficult for scientists to persuade policymakers, the public, and institutions to implement techniques to minimize or slow down the effects. Some researchers, including Nobel Prize–winning economist Daniel Kahneman, believe there is no path to success on climate change. Others see climate change as an example of “perfect market failure.” George Marshall, writing in New Scientist, points out that it is the large indifference in the “middle” majority that is the stumbling block, and that one factor is an unwillingness to face mortality. Ironically, he says, the systems that govern our own attitudes "are just as complex as those that govern energy and carbon, and just as subject to feedbacks that exaggerate small differences between people."
NPR: As the most severe Ebola epidemic ever unfolds in West Africa, some researchers are studying it through the use of computer simulations. The goal is to see how the outbreak might spread and which public health measures could prove most effective in containing it. The effort is complicated by a number of factors, including the uncertainty in the total number of dead and infected people, how many infected people stay at home rather than go to hospitals, and how burial practices can spread the infection. Although the situation is too complex for computer models to come up with definitive answers on how many people will ultimately die and exactly when the epidemic will end, they do underscore the need to act quickly before the Ebola outbreak becomes too large to contain.
Climate Progress: Among the developed countries of the world, Germany is proving to be very successful at making the switch to renewable energy sources for its electricity production. That effort was reflected in the first half of 2014, when the country managed to generate one-third of its electrical power from renewables. That is a remarkable accomplishment in view of the fact that most renewables are inherently intermittent: The Sun only shines during the day, and the wind doesn’t always blow. Moreover, Germany's electrical power grid has proven to be very reliable: Since 2008 the average number of minutes that electricity was lost per customer each year has been less than 16—far less than in any other country in Europe or the US. However, the switch has not come without a price: Germans pay more for their electricity. Regardless, the country remains committed to getting 80% of its power from renewables by 2050.
BBC: Researchers have built a swarm of more than 1000 small robots that can shuffle around on three spindly legs to form two-dimensional shapes. Although the 3-cm-sized robots are fed the same computer program, they modify their movements based on what their neighbors are doing. Modeled on the swarm behavior of living organisms such as ants and birds, the so-called Kilobots could one day be used to develop self-assembling tools and structures. The tiny robots are not fast, however: Each shape can take 6 to 12 hours. "Actually watching the experiment run is like watching paint dry,” says Michael Rubenstein of Harvard University, coauthor of the group’s study published in Science.
Telegraph: NASA’s Stardust spacecraft was launched 15 years ago to collect dust samples from the coma of comet Wild 2 and from the outer reaches of space. Fitted with collectors made of a silica-based aerogel, Stardust returned to Earth in 2006 with at least a million particles in separate sets of detectors. One set was open when the craft passed through Wild 2 and then closed, the other closed through the comet's passage and kept open in a region of space suspected to have interstellar particles. To help sort the vast amounts of data, NASA turned to crowdsourcing, in which citizen scientists used their home computers to scan the collectors for the tracks left as particles hit the aerogel and became embedded. Scientists say that seven of the particles in the second set may be interstellar dust from outside our solar system.
MIT Technology Review: Being made of plastic, organic LEDs are intrinsically flexible. Although OLEDs could be used for displays that can be bent or rolled, it's challenging to protect the material from the few molecules of oxygen or water vapor that suffice to degrade performance. Kateeva, a startup in Menlo Park, California, has devised a solution to the protection problem. By using inkjet technology, the company can coat OLED displays faster and more cheaply than can current processes. Meanwhile, another startup, Canatu of Helsinki, Finland, has resolved a problem that besets flexible touch-sensitive displays. The flat, rigid screens of tablet computers and smartphones rely on tin-doped indium oxide, which is too brittle for use on a flexible screen. For its displays, Canatu replaces the oxide with a thin, flexible film covered with a layer of carbon nanobuds—that is, carbon nanotubes topped with spheres of carbon atoms.