New Scientist: Patent trolls are companies that buy the rights for patents that, in some overly broad cases, shouldn’t have been granted at all. The trolls then assert those rights by threatening lawsuits against businesses that infringe the patents—often settling out of court, with the targets agreeing to pay crippling licensing fees. The vast majority—70% to 90%—of the patents such companies hold are software or business practices and they target not just manufacturers but technology users. Now the White House has called for Congress to require the US Patent and Trademark Office to institute several policies to reduce patent-troll lawsuits. The White House has also instituted policies of its own that it hopes will reduce the estimated $29 billion spent each year fighting patent trolls and will hold those companies accountable for frivolous lawsuits.
Nature: Nearly half of Antarctica’s ice shelves—the portions of the ice sheet that extend over the ocean—are thinning due to warming ocean currents, according to new monitoring data and computer modeling. In fact, some ice sheets are losing more ice from such basal melting than from the calving—or breaking off—of icebergs, once thought to be the primary factor in ice-shelf dynamics. Eric Rignot of the University of California, Irvine, and colleagues, whose paper has been published in Science, also found that about half of the total meltwater comes from just 10 small ice shelves along the southeast Pacific coastline. Despite those losses, other ice shelves are thickening or maintaining equilibrium. Rignot and coworkers’ findings point up the difficulty of projecting long-term ice-sheet evolution because of the many factors involved, including sea-floor topography and ocean circulation, which change over time.
MIT Technology Review: Optical cloaking has recently been demonstrated to work on large scales. Taking invisibility in an entirely different direction, a new paper from Jeng Yi Lee and Ray-Kuang Lee of the National Tsing-Hua University in Taiwan suggests it may be possible to hide objects from quantum mechanical interactions at the nanoscale. They say that the same concepts that allow invisibility to the electromagnetic spectrum can be applied to quantum effects by using Schrödinger’s equation instead of Maxwell’s equations. The goal would be to construct a device that reduces to zero the probability distribution of the presence of a specific quantum effect within the shielded area. However, it would only be effective for specific versions of the equation, so one shield could hide an object from the quantum properties of electrons but nothing else. Although the paper is theoretical, the researchers suggest that current technologies are advanced enough to create real versions of their theorized nanoshells.
Nature: The ability of rocks to flow is behind a range of phenomena, including plate tectonics and the convection of the mantle. To better understand rock flow, Hongzhan Fei of the University of Bayreuth in Germany and his colleagues examined individual crystals of olivine, one of the common minerals in Earth’s mantle, under pressures and temperatures similar to those at depths of 100 km to 200 km. They found that silicon was the mineral’s slowest moving atom, which the team believes is the limiting factor in the rocks’ ability to flow. The researchers found that increasing the water content did not significantly increase the silicon atoms’ movement rate, contrary to some previous studies. And it still is not clear whether silicon is actually the determining factor in rock viscosity.
BBC: China’s Shenzhou-10 capsule successfully docked with the country’s orbital laboratory Tiangong-1. The capsule is carrying three astronauts—Nie Haisheng, Zhang Xiaoguang, and Wang Yaping, who is the second Chinese woman in space. In the 12 days they will be aboard Tiangong-1, the astronauts will perform various experiments and hold live video classes for Chinese students. They will also practice manually docking with the lab, which will require separating the capsule before flying it around the lab and reconnecting. This is China’s fifth manned space mission, and the third to the Tiangong-1 lab, which has been in orbit for more than 600 days. It will also be the last visit to the lab, which will run out of supplies for astronauts. The Chinese space agency has announced that the lab will be deorbited and crashed into the Pacific Ocean, but it has not said when that will occur. A replacement lab, Tiangong-2, will likely be launched in the next few years.
Science: Although cheetahs are the fastest land animals on Earth, it turns out that for hunting, their ability to stop and turn is more important than their speed. Alan Wilson of the Royal Veterinary College in London and his colleagues developed a collar equipped with GPS, accelerometers, gyroscopes, and other sensors to record the movements of cheetahs when they hunt. To extend the collars’ recording ability, the researchers also included solar-powered battery chargers and sensors that activated the collars only when the cheetah moved at the times of day when it was known to hunt. When operating, the collars record data 300 times a second and relay them to the researchers. Over 18 months, five cheetahs wore the collars, which recorded 367 hunts. The data showed that the animals usually maxed out at 60% of the recorded top speed of 106 kph, and they usually only reached that speed for one to two seconds. The key to the cheetahs’ hunting ability is that they can rapidly slow down in a single stride and then turn and accelerate again with four times as much power as the fastest human sprinters. They also found that the animals often hunted in nongrassland areas and throughout the day, not just at dawn and dusk.
Science News: Computers store data in two different ways: short-term, capacitor-based dynamic random access memory (DRAM) and long-term, magnetic-disk or solid-state drives. Unlike the latter, the former stores data only while the computer is on. But DRAM is significantly faster to read from and write to and doesn’t degrade from overwriting the way long-term media do. For decades, researchers have been developing alternative data storage technologies that blend the capabilities of the two types. One of the alternatives is ferroelectric RAM, which applies a voltage to read individual bits. Because the process destroys the data, it then has to immediately rewrite it. This destructive reading procedure limits the lifespan of the media. Ramamoorthy Ramesh of the University of California, Berkeley, and his colleagues at Nanyang Technological University in Singapore have developed an alternative FRAM that uses a nondestructive reading process: The device shines a light at individual bits and reads the current across them. The process increased the lifespan of the material to hundreds of millions of rewrites. FRAM is still faced with lower data densities and higher costs than solid state media, however, so it remains far from being ready for widespread commercial use.
Ars Technica: As global temperatures increase, sea levels are predicted to rise, more severe weather events could occur, and agriculture and animal habitats may be disrupted, all of which will cause problems for humans. In an effort to limit world temperature rise to no more than 2 °C by 2020, the International Energy Agency (IEA) has proposed a four-step plan of action: accelerate the phasing out of fossil fuels, limit the construction and use of the least efficient coal plants, capture more of the methane generated before it enters the atmosphere, and improve the efficiency of buildings, vehicles, and industrial processes. Despite the reasonableness of the proposal, similar efforts in the past have been met by opposition from countries and companies because of the initial costs and potential loss of income from not developing their fossil-fuel reserves.
Nature: Thanks to their ability to switch on and off and amplify signals, transistors are a key component of electrical devices. Several projects have demonstrated the possibility of creating transistors that are controlled by photons instead of electrical signals. The most recent, created by Wenlan Chen of MIT and her colleagues, relies on only a single photon to achieve this functionality. The proof-of-concept project uses a cooled cloud of cesium atoms and a principle called electromagnetically induced transparency in which a photon with a specific energy switches the cloud of cesium atoms between excited and ground states. When the atoms are in ground states, they allow light to pass through the cloud. Neither Chen’s transistor nor other optical transistors are likely to replace traditional ones any time soon, however, as the size and energy costs are significantly greater.
BBC: From images captured by NASA’s Mars Reconnaissance Orbiter, researchers have observed long, closely packed grooves on Mars’s surface. Unlike anything seen on Earth, the linear gullies were probably formed by the movement of dry ice rather than by liquid water flow, according to Serina Diniega, a planetary scientist at NASA’s Jet Propulsion Laboratory and lead author of a paper published in the journal Icarus. Diniega and her colleagues base their theory on evidence of pits at the bottom of the gullies. In debris flows, water carries sediment downhill and deposits it in a fan shape; in linear gullies, material is not transported but pushed to the sides. To test their theory, the researchers slid blocks of dry ice down sand dunes in the western US. Despite differences in temperature and pressure from those on Mars, they found that as the melting blocks of ice slid down the dunes, they divided the sand into sections, similar to the features seen on Mars.