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House appropriations subcommittee approves FY 2016 funding bill for NASA, NIST, NOAA, and NSF

18 May 2015
The bill was approved quickly and with little partisan rancor.

New lows for magnetic shielding

18 May 2015
Greater magnetic field attenuation over a larger volume is a boon for ultraprecise measurements.

Holographic 3D printing technique creates microbatteries

18 May 2015

Ars Technica: The continued miniaturization of electronic devices has recently been hindered by the difficulty in miniaturizing energy storage. The size of such batteries severely limits their storage capacity. Now Paul Braun of the University of Illinois at Urbana–Champaign and his collaborators have combined 3D holographic lithography with traditional photolithography to create a 2-mm-square, 10-µm-thick lithium-ion battery. The holographic lithography was used to create a regularly patterned 3D lattice. Photolithography was then used to apply 2D electrodes to the internal structure. The resulting battery has lithium manganese dioxide cathodes, nickel–tin anodes, and an energy density of 6.5 μWh cm−2 μm−1.

Strontium allows for mapping of salmon migrations

18 May 2015

New Scientist: Small calcium carbonate deposits called otoliths form in the inner ears of salmon as they age and collect trace amounts of other elements in the water. As otoliths grow, they create layers similar to tree rings. Sean Brennan of the University of Alaska Fairbanks and his colleagues have now used the strontium isotopes in those mineral records to map where individual Chinook salmon have been and for how long. Strontium, which lies below calcium in the periodic table, dissolves out of river rocks, and different regions have different isotope concentrations. Using water and other samples they took from the Nushagak River in Alaska, the researchers were able to determine the exact birthplaces of more than 400 salmon caught in 2011. They also found that 70% of the fish stayed in the same stream they were born in, with the rest migrating to other habitats.

Galaxies die slowly as they use up the gas needed to form new stars

18 May 2015

BBC: A massive comparison of dead and dying galaxies and active galaxies has provided clues to the late stages of galactic life. Yingjie Peng of the University of Cambridge and his colleagues combed through images collected by the Sloan Digital Sky Survey to examine 23 000 galaxies that are no longer producing stars and 4000 galaxies that are producing stars. In the unproductive galaxies, Peng's team detected significantly more heavier metals than in the productive galaxies. If the galaxies had stopped producing new stars due to the sudden loss of gas clouds, the metal concentration would not have continued to grow. That suggests that the death process is drawn out over time. And the images showed that the active, star-forming galaxies were, on average, 4 billion years younger than the inactive galaxies.

First joint ATLAS and CMS paper sets record with 5154 authors

18 May 2015

Nature: A 33-page paper published on 14 May in Physical Review Letters has only 9 pages of text about the experiment and data; the remaining pages list the 5154 contributors to the project. It is the first joint paper by the ATLAS and CMS teams at CERN's Large Hadron Collider. The two teams decided to publish together because their combined data narrowed the mass of the Higgs boson to within ±0.25%. Both teams have been listing all the scientists involved because they believe there is no fair way to split credit for the project. A CMS paper from 2008 was the first to surpass 3000 authors.

Oktay Sinanoglu

15 May 2015

Harvey Kaplan

15 May 2015

Microsoft adding stress management to its enhanced-reality headset

15 May 2015
BBC: Microsoft is developing a headset designed to immerse the wearer more fully in the cyberworld. The HoloLens, currently in development, includes a holographic computer that superimposes holograms on the user’s field of view. That so-called mixed reality is supposed to “unlock all-new ways to create, communicate, work, and play,” according to the company’s website. Besides turning one’s surroundings into a giant computer screen, the device is also being equipped with a biometric data sensor system to determine whether the user is becoming stressed and then take action to help relieve that stress. One example given was of a person trying to assemble a bookcase: If the HoloLens senses that the person is becoming frustrated, it may offer up a video with step-by-step assembly instructions. However, because of the complexities involved, including how to discern stress in different individuals and how to differentiate between positive and negative stress, it may be a while after launch before this feature becomes available.

Unexpected quartet of quasars

15 May 2015

Smithsonian: Quasars are massively bright, short-lived objects thought to be the result of material falling into supermassive black holes. Finding two of them near each other is unusual, but Joseph Hennawi of the Max Planck Institute for Astronomy in Germany and his colleagues were even more surprised to find four within 600 000 light-years of each other. The grouping was found as part of a survey of quasars using the Keck observatory in Hawaii. The images also revealed that all four are inside a large cold cloud of gas. Only about 10% of quasars are in similar clouds; hot clouds are much more common. That suggests current models of quasar formation may need to be adjusted. Hennawi's group thinks that the quasar quartet may represent the early stages of a galaxy cluster forming, because the region surrounding the collection has many more galaxies in it than does the average region of space.

Warm-blooded fish found in deep ocean

15 May 2015
Los Angeles Times: Although most fish are cold-blooded, one deep-ocean dweller has been found to be completely warm-blooded. Despite the coldness of the water where it lives, hundreds of meters beneath the ocean surface, the opah manages to keep its internal body temperature 5 °C warmer than its surroundings. Through the use of sensors mounted on the fish, researchers found that nets of blood vessels located near the fish’s gills operate as a heat exchanger; they use warm blood flowing to the gills to heat up the cold blood that has just passed through. The opah generates heat constantly by the almost nonstop flapping of its pectoral fins as it swims around. Because it preys on fast-moving animals such as squid, being warm-blooded helps the opah to see better and respond more quickly.

Twenty startups

15 May 2015
Young energy companies from around the world competed for cash in this week's Challenge Cup.

Graphene-coated nanodiamonds result in very low friction

15 May 2015

Ars Technica: Superlubricity is a phenomenon that occurs when the coefficient of friction between two surfaces is dramatically reduced to near 0. Until now, it had only been detected in small samples of pairs of incompatible crystalline surfaces. Now a team from Argonne National Laboratory has produced superlubricity on a larger scale. Initially working with graphene and diamond, they tested two surfaces, one covered in graphene and one covered in diamond. The coefficient of friction was low, but not to the point of superlubricity. They noticed, however, that the graphene splintered and created curls of material that then collapsed under the pressure. Adjusting the setup, they placed nanoscopic diamonds between the two surfaces, and the coefficient of friction dropped dramatically. Electron micrographs revealed that the curls of graphene wrapped themselves around the nanodiamonds, which acted like ball bearings.

Tentacle-like robotic arm uses the granularity of coffee

14 May 2015

BBC: A new robotic arm has been developed by Tommaso Ranzani of the Sant'Anna School of Advanced Studies in Pisa, Italy, and his colleagues. The device lacks a rigid skeleton, similar to the tentacles of octopi. Inflatable compartments surround a central tube filled with coffee grounds. As compartments are inflated and deflated to change the length and bend of the arm, suction is applied to the central tube, which causes the granular material to "jam" and the arm to become rigid. Ranzani's team hopes to develop the arm for use in surgical systems.

New technique diagnoses radiation exposure

14 May 2015

Science: Radiation exposure, even at life-threatening levels, can be hard to detect until a patient becomes symptomatic. Several studies have shown that an analysis of the microRNA that circulates in blood can reveal whether a person has been exposed to radiation. Now Dipanjan Chowdhury of Harvard Medical School and his colleagues have used microRNA to determine the level of exposure and predict survival. They exposed mice to a range of radiation levels, from mild to lethal, and compared microRNA analysis from the next day with blood and bone marrow samples taken at four later times. Out of 170 microRNAs identified, the concentrations of 5 of them varied markedly depending on the amount of radiation the mice received. From those concentrations, Chowdhury's group could determine how much radiation was received well before the bone marrow samples showed damage.

Longitudinal waves in piano strings

14 May 2015
At last, decades-old theoretical work meets empirical evidence—and survives the test.

Theoretical planet could have corkscrew orbit between binary stars

14 May 2015

New Scientist: Inspired by a rare molecule, Eugene Oks of Auburn University in Alabama has suggested the possibility of an unusual orbit for a planet in a binary star system. In Oks's proposed system, the planet follows a corkscrew path back and forth around a line between the two stars rather than circling both stars. Oks draws a comparison with the one-electron Rydberg quasimolecule in which the electron follows a similar corkscrew path due to electromagnetic forces. Although the presence of a planet in such systems could be found using current exoplanet detection techniques, distinguishing them from traditional orbits would be challenging.

Rare B-meson decays detected at LHC

14 May 2015
Los Angeles Times: Although the Large Hadron Collider (LHC) at CERN had until recently been shut down for repairs and upgrades, researchers sifting through data taken in 2011–12 have now reported evidence of certain B-meson decays, events that are exceedingly rare and can only be determined indirectly by studying the particular shower of particles into which they decay. Their detection is sought as a way of testing the standard model of particle physics, which has made fairly precise predictions concerning B-meson behavior. In a their paper published in Nature, researchers in the CMS (Compact Muon Solenoid) and LHCb (Large Hadron Collider beauty) collaborations say that the decay rate of the strange B meson matches that predicted by the standard model. However, the decay rate of the nonstrange B meson exceeded the standard-model prediction by almost fourfold, “albeit with a lower statistical significance than obtained for the strange B meson,” writes Daria Zieminska of Indiana University in a commentary on the research. Now that the LHC has been restarted, it is expected to be able to double the production rates of B mesons, which should lead to further fine-tuning of the standard model or even provide evidence for theories beyond the standard model, such as supersymmetry.

Japan works toward space-based solar plant

13 May 2015
Telegraph: The Japan Aerospace Exploration Agency (JAXA) and Japan Space Systems are working together on a space-based solar panel array to provide power on Earth. The Space Solar Power System (SPSS) would consist of a spacecraft with a screen of solar panels almost 2 km2 in size. A system comprising solar cells and antennas would convert the electricity generated into microwaves and then transmit the microwaves to Earth. The advantage of a space-based solar panel is that it would not be affected by weather and could be positioned to always face the Sun. One SPSS unit could generate about the same amount of energy as a nuclear reactor, according to Daisuke Goto of JAXA. The project presents challenges, however, and could take 30 years to launch.

Sugar structures in proteins poorly understood

28 April 2015
Science: Because proteins often come with carbohydrates attached, knowing the sugars’ structures is important for understanding the proteins' function. But unlike the proteins themselves, whose structures are routinely derived from x-ray crystallography, the sugars have proven much more difficult to map. After an examination of some 50 000 sugar structures recorded in two major protein databases, Kevin Cowtan of the University of York and his colleagues have determined that 25% of them are wrong and another 64% are questionable. Therefore, they say, the structural biology community needs to work to improve measurement tools and techniques in order to better understand the function of glycoproteins and take advantage of their potential beneficial effects.

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