Physics Today Daily Edition
The Telegraph: Computationally modeling chemical processes from quantum mechanical principles has been a challenging task because of the large number of pieces and the large number of steps in interactions that need to be calculated. Now Peter Coveney, James Suter, and Derek Groen of University College London have developed an efficient way of modeling the behaviors of composites of clays and polymers from the quantum scale up. They were able to accurately model the characteristics of synthetic materials they'd created in the lab; they began the modeling with the behavior of the materials' electrons and then progressed to the atomic level and then to the molecular level. Their modeling system could be useful for predicting the behaviors of potential new materials, including new composites that contain molecules like graphene.
New York Times: On 12 December Congress approved the establishment of a new national historic park to preserve sites associated with the World War II secret Manhattan Project, which built the world's first atomic weapons. The park will encompass lands and buildings in New Mexico, Tennessee, and Washington, including the home of J. Robert Oppenheimer, the scientific director of the project, and buildings where much of the research and construction of the Trinity device and the Fat Man and Little Boy bombs took place. The effort to preserve the various sites was led by the Atomic Heritage Foundation. President Obama is expected to sign the legislation into law this week.
BBC: A 120 000 km2 area that accounts for just 3% of the Peruvian Amazon basin contains almost 50% of the basin's carbon stock. Freddie Draper of the University of Leeds, Katy Roucoux of the University of St Andrews, and their colleagues combined two years of measurements on peat depth, density, and carbon percentage with satellite imagery to reach that conclusion. The imagery revealed that the peatlands were more widespread than expected. The direct measurements of ground carbon revealed that the peat accounted for 90% of the area's carbon. Draper and Roucoux say that the peatlands are still mostly intact but that preservation efforts should be started now to prevent any damage to the ecosystems.
Earth Magazine: Sea-floor methane deposits are commonly found leaking gas in tectonically active areas or in areas rich in petroleum. They are considered to be a potentially significant contributor of greenhouse gases. Now Adam Skarke of Mississippi State University and his colleagues have found 570 methane seeps along the tectonically quiet and oil-poor East Coast of the US. Skarke's team used multibeam sonar, commonly used for producing 3D maps of the sea floor, to find the seeps. Previous scans of the region did not have a resolution capable of detecting the small bubbles up to 1.6 km below sea level. Despite the large number of seeps found, the amount of gas being released by them is quite small. However, the discovery suggests that the search for seeps should be expanded to areas that were not previously considered likely sites.
New York Times: FuelCell Energy has received a $2.5 million grant from the US Department of Energy for an experimental fuel cell it developed that can be used to capture carbon dioxide emissions from coal power plants. The fuel cell combines natural gas and air without combustion to produce CO2 and steam and to generate electricity. Then the mixture is easily cooled to −40 °C so that the CO2 can condense and separate out. When the fuel cell is fed waste air containing 13% CO2, about the level from a coal power plant, the additional CO2 is captured in the condenser. As an additional bonus, the fuel cell generates excess electricity that can be used by the power plant.
Ars Technica: The visible matter that makes up galaxies is primarily in the form of stars, but many galaxies have large clouds of molecular gas around them. How that gas got there is unclear because most theories about galaxy formation predict that the gas should have stayed in the galaxies and coalesced into stars. Now observations of a distant galaxy may provide some clues into the process. The observed galaxy, J0905, is extremely compact, with half of its star formation coming from a region just 100 parsecs in diameter. It is spewing gas outwards into space at a flow rate of 2 500 km/s, 10 times more than the average for other galaxies. Curiously, the mass of the gas lost each year is roughly equal to the mass of new stars that J0905 produces each year. Because of the galaxy's compactness, the combined radiation from the new stars appears to be the source of the "wind" driving the gas out of the galaxy.
New York Times: Ernie Button, a photographer in Phoenix, Arizona, saw the fine lines in the filmy residue of a glass of Scotch and turned it into art by shining colored lights through the films and taking pictures. Over time, he began detecting patterns and similarities between different types of whiskeys and other alcohols. So he reached out to Peter J. Yunker, who had published a paper explaining the uneven formation of coffee rings, but Yunker was unable to help him. Button then found Howard Stone of Princeton University by doing a Google search of "fluid mechanics" and "art." Stone and his colleagues began testing different liquors and their own alcohol mixes. They found that the patterns formed because of the different evaporation rates of ethyl alcohol and water. As the alcohol evaporates, the surface tension of the water left behind changes, which in turn affects the way the water flows and the particulate residue gets distributed. They also believe that whiskey contains a surfactant and polymers that their artificial water and alcohol mixes did not. The surfactant changes the surface tension of the water, and the polymers adhere to the glass, all of which affects the resulting patterns. Stone thinks that the work has practical applications, such as improved printer inks.
Nature: Rapid advances are being made in the field of brain–computer interface devices that connect with the central nervous system to restore motor control in patients with paralysis or amputation. Devices range from implants in the brain to electrodes and sensors placed on the scalp. The implants are the riskiest because they require surgery and it’s not known how long the electrodes can safely remain in the brain. As such devices will soon reach the point of being commercially viable, manufacturers are also working to ensure that they meet the safety regulations of the US Food and Drug Administration and to persuade health insurers to pay for them. The FDA recently held a workshop in Silver Spring, Maryland, to discuss and obtain public feedback on just such issues.
Ars Technica: Quasars, which are black holes at the center of galaxies, produce more light from their accretion disks than is produced by the rest of the stars in their parent galaxies combined. A survey of 93 extremely distant quasars by Damien Hutsemékers of the University of Liège in Belgium and his colleagues has revealed a possible connection between quasars and the universe's large-scale structure. The light from the quasars they looked at was produced when the universe was only one-third as old as it is now. The researchers noticed that some of the quasars' axes of rotation appeared to be aligned with each other despite being separated by billions of light-years. To determine just how closely aligned they were, Hutsemékers's team measured the polarization of the light from the quasars, which has previously been shown to correlate to the orientation of a quasar's accretion disk. Of the 93 quasars, 19 were highly polarized and had broad radiation spectra, a sign that the quasar is highly inclined with respect to Earth. By comparing those quasars with a map of the filamentary structure of the universe, the researchers show that the quasars are all aligned parallel to the filaments in which they are located. The researchers believe there is a less than 1% chance that this is a random distribution.
BBC: A recent study published in the Proceedings of the National Academy of Sciences confirms the hypothesis that the parts of the brain that develop last tend to be the first to show signs of age-related decline. Moreover, two common forms of dementia, Alzheimer’s disease and schizophrenia, appear to affect the same regions of the brain. The findings highlight the possible lifelong consequences of genetic and environmental factors that occur early in life. The information is encouraging, according to medical researchers, because a better understanding of the diseases' pathology could one day allow doctors to identify those most at risk and provide a means of treating them or possibly even preventing the diseases from ever developing.
NPR: As the world’s third largest producer of pistachios, Turkey has had to find ways to get rid of thousands of tons of leftover shells. Now the country proposes using its green waste to its advantage by turning the shells into biogas to power a new eco-city. Other green cities have been springing up around the world, each fueled by various renewable materials, including macadamia nuts in Australia and decaying garbage in Mexico. If the project is deemed feasible, construction on the new city would begin in the next two years.
New York Times: Raised from a shipwreck in 1901, the Antikythera mechanism has long puzzled scientists regarding its origins and maker. The clocklike device, with its numerous bronze gears and dials, appears to have been used to predict astronomical positions and eclipses. Hence it has sometimes been called the world’s first analog computer. Now Christián Carman of the National University of Quilmes in Argentina and James Evans of the University of Puget Sound in Washington have used the device’s eclipse predictor to more accurately date when the device was built. Based on the new information, they say the device was probably constructed around 205 BC, some 50–100 years earlier than previously believed. Although scientists have speculated that the Antikythera mechanism may be linked to the famed ancient Greek mathematician Archimedes, Evans said too little is known about ancient Greek astronomy to ascertain who could have come up with such a device.
New York Times: Despite yesterday’s deadline, no final agreement has been reached concerning Iran’s nuclear program. Leaders from the P5 + 1 nations (China, France, Russia, the UK, and the US, plus Germany) met with Iranian officials in Vienna to try to resolve the yearlong effort to get Iran to dismantle parts of its nuclear infrastructure and cut the number of centrifuges. Although the meeting ended with no breakthrough compromise, the US and its allies have decided to extend the deadline by seven months. US secretary of state John Kerry and Iranian foreign minister Mohammad Javad Zarif, who have met several times and developed a strong working relationship, both expressed optimism that the talks had made “real and substantial progress” and that a solution may well be found in the next few months.
Smithsonian: Mark Kelly and Scott Kelly, who have both worked as astronauts with NASA, are the only set of twins to have traveled in space. Although Mark retired three years ago, he is about to become part of a NASA study when identical twin Scott returns to space in 2015 to spend a year on board the International Space Station. No US astronaut has spent that long in space, so NASA will use the opportunity to study how the long-duration spaceflight affects Scott. The agency will look at such things as the effects of weightlessness, radiation, isolation, and confinement. Scott's results will be compared with those from tests conducted on Mark, who will remain on Earth. The results will be used to help prepare astronauts for longer space trips such as to Mars.