Physics Today Daily Edition
Sydney Morning Herald: Two different groups of researchers have written computer algorithms that can not only pick out individual objects in an image but also describe the entire scene. Both groups, one at Google and the other at Stanford University, were inspired by the neural networks found in the brain. They incorporated two types of networks: one that recognizes images and one that focuses on human language. The researchers trained the artificial-intelligence software by exposing it to images that had descriptive sentences written by humans. Once it learned to pick out patterns in the pictures and descriptions, the researchers tried it out on unfamiliar images. A few of the sentences the software generated included "man in black shirt is playing guitar" and "girl in pink dress is jumping in air." Although still nowhere as accurate as humans, the new system is much more advanced than previous designs. Possible uses include sifting through the billions of images and video online to better catalog and describe them, helping people who are visually impaired to navigate on their own, and monitoring public spaces for illegal activity and alerting the police.
MIT Technology Review: A series of boxes spaced 10 km apart, each of which pairs an IR laser with a directional millimeter-wave radio transmitter, may soon provide wireless internet access. Developed by a company called AOptix, the paired signals each transmit the same data at 2 GB/s, which provides redundancy in case conditions prevent one signal from reaching the next box. Chandra Pusarla, the company's senior vice president of products and technology, says the redundancy guarantees the system will experience only five minutes or less of downtime per year. It is currently undergoing tests by three US wireless carriers and is already being used in Mexico and Nigeria. The technology is useful both in urban environments, where upgrading copper wiring to fiber optics can be costly, and in rural environments, which lack any fiber-optic infrastructure.
Nature: Synthetic biology creates cells that perform logic operations through gene expression. To truly function as computers, those cells need a way to store and access data, but most attempts to achieve that goal have been limited. Now, MIT's Timothy Lu and Fahim Farzadfard have developed a way to use DNA for data storage that can take multiple inputs simultaneously and also keep a record of the accumulation of data over time. The technique, which they call Synthetic Cellular Recorders Integrating Biological Events (SCRIBE), uses a cellular structure known as a retron, which produces single-strand DNA. Lu and Farzadfard created a culture of Escherichia coli in which the retrons responded to the presence of a certain chemical by making the bacteria resistant to antibiotics. The amount of chemical introduced altered the proportion of the bacteria that became resistant. Used that way, the distributed system can store information in a range instead of in a binary state. Lu and Farzadfard also showed that the process is reversible, can be triggered by light, and can "record" the influence of multiple triggers.
New York Times: An electrical device that attaches to the scalp has been shown to slow the growth of brain tumors. Produced by Novocure, a company in the UK, the device consists of four pads that are glued to a patient’s shaved scalp and connected by wires to an operating system and power supply. The system delivers low-intensity, alternating electric fields, called tumor-treating fields, that disrupt cell division. The device is being tested on people with glioblastoma, the most aggressive and malignant type of brain tumor. Early results show that the device extended patients’ lives by three months, and some have survived more than two years. The company next plans to test the device on other types of cancer.
Ars Technica: At 90 km long and 40 km wide, the Markagunt gravity slide in southwest Utah is a manifestation of the largest known landslide on Earth. During the event, which happened about 21 million to 22 million years ago, rocks up to 2.5 km2 and 200 m thick were sent sprawling some 30 km or more. Because the debris field is so large, geologists had thought that it represented a series of individual landslides. In a recent paper published in Geology, however, a group of researchers propose that it was the result of a single, catastrophic event. Over time, they say, volcanic eruptions may have built up a thick wedge of material on top of the clay-rich sedimentary soil, which is structurally weaker. Pressure from the underlying magma then pushed the surface upward, which in turn put stress on the rocks and created faults and fractures. A violent eruption or earthquake could have then set the whole thing in motion. The researchers say the site could provide insights into the potential hazards of such catastrophic collapse.
Science: Since 2005 the US Census Bureau has been conducting an annual 72-question survey to collect housing and demographic information from some 3.5 million people. The survey supplements the decennial census required by the US Constitution. Some members of Congress, however, have objected on the grounds that it poses an unnecessary burden on the public and that the government has no business asking some of the questions. This year the Census Bureau conducted an extensive review of each survey question to determine two criteria: whether a law required the collection of that information and how much time it takes the respondents to answer. As a result, seven questions may get dropped. Social science researchers are unhappy with the proposal to drop question 12, which asks survey takers to identify their college major. The researchers say the information is essential for science and technology policy planning. Next follows a 60-day comment period, during which the statistical community hopes to persuade the Obama administration to reverse the decision.
Los Angeles Times: Astronomers believe that Uranus does not have a warm core and that heating from the Sun drives the formation of the planet's storms. Therefore, storm activity on the planet should peak during equinoxes. But recent observations have revealed a spate of storms at a rate much higher than during the most recent equinox, seven years ago. In August, Imke de Pater of the University of California, Berkeley, and her colleagues, with the help of amateur astronomers and time on the Hubble Space Telescope, spotted eight storms at various altitudes. One of those storms was the brightest ever at the 2.2-µm wavelength. That height puts the storm just below Uranus's tropopause. The researchers are uncertain what could have been driving the storms, but they know that whatever the cause, it will require revising theories about Uranus.
New York Times: Two independent studies ordered by the Pentagon have revealed wide-ranging problems with the management of the US Air Force's and US Navy's nuclear weapons, facilities, and ships. The probes were initiated following the uncovering of academic cheating and several incidents of misbehavior by senior officers. The problems include blast doors that failed to seal and the fact that only a single wrench existed for attaching nuclear warheads to missiles. That one wrench was being shipped via FedEx between the facilities that manage the warhead stockpiles. The emergency repairs and equipment replacements are expected to add several billions of dollars to the Department of Defense's expenses over the next five years. The two studies' investigators—senior Pentagon officers conducted one study, and two retired officers ran the other—visited all the military's nuclear installations and interviewed nearly 1500 personnel. Both investigations found that the problems were rooted in staffing shortages, long-standing cultures of micromanagement that ignored larger issues, personnel management practices that degraded morale and favored test scores over effectiveness, and the age of many of the systems.
BBC: A nearly 50% increase in the number of yearly lightning strikes is expected between 2000 and 2100 if current predictions for global temperatures are correct. A study by David Romps of the University of California, Berkeley, and his colleagues found a new method for relating temperature and lightning by estimating the amount of energy available to drive lightning storms. They found that every 1 °C of temperature increase corresponds to a 12% increase in the number of lightning strikes. Romps's team compared that prediction with data from the US National Lightning Detector Network and found it matched. An increase in lightning strikes will also cause an increase in wildfires, which contribute to air pollution. Lightning also causes chemical reactions in the upper atmosphere that already account for the majority of the nitrogen oxide greenhouse gases present there.
BBC: Jean-Claude Juncker, the new president of the European Commission, has decided to close the Bureau of European Policy Advisers, which includes the EU Chief Scientific Adviser (CSA). The position has been filled since 2012 by Anne Glover, the former chief scientist of Scotland. Glover had faced criticism for her support of genetically modified organisms in agriculture, and several groups opposing her wrote a letter to Juncker asking him to eliminate the CSA position. British members of the European Parliament have spoken out against Juncker's decision, which they said came after he promised he would maintain the office. They also raised concerns that the EU will no longer have access to scientific advice necessary to make decisions on a wide range of political issues. However, there are rumors that Juncker may select a panel of new advisers covering a range of topics.
New Scientist: When a remotely controlled drone crashes and cannot be recovered, the wreckage can be looted, can let someone know that they are being spied on, and pollutes the environment. Now, Lynn Rothschild of NASA's Ames Research Center in California and her colleagues have created a quadcopter drone from materials that are almost all biological or biodegradable. The body was grown into shape using a root-like fungus called mycelium and then covered in protective sheets of cellulose soaked in a protein used by paper wasps to waterproof their nests. The electrical circuits were printed using silver nanoparticle ink. In the drone's first test flight, the motors, propellers, battery, and control systems were the only non-biodegradable parts. The team's next step is to grow biological sensors for the craft.
MIT Technology Review: Just like fingerprints, every person's iris has a unique pattern, which is why the iris has been used for identification and security purposes for some time. Now, a company called EyeLock has created Myris, a peripheral device that can be plugged into a computer and used as an alternative to typing a password. Myris scans the user's iris and stores the information in encrypted form. It can be configured not just for use for logging into the computer but also to specific programs or websites. The company is already in the process of working with several computer manufacturers to have the device built into their machines.
Nature: Yesterday, the European Space Agency's Philae lander separated from the Rosetta spacecraft and successfully landed on comet P67/Churyumov–Gerasimenko. This is the first time that any spacecraft has landed on a comet. There were some bumps, literally: The lander's harpoon system misfire resulted in Philae's bouncing twice before finally settling into position. The lander maintained power and established contact with the Rosetta orbiter. The final position appears to be partially in a shadow, which reduces the amount of light available for the lander's solar panels. However, the first science mission is planned to run entirely off of the craft's batteries for the next two days. The lander is already taking pictures and beginning to run other tests, including drilling into the comet's surface. After the initial science mission is complete, Philae will enter hibernation. As the comet approaches the sun, if the lander receives enough sunlight, it will recharge the batteries for further observations.