Physics Today Daily Edition
Nature: Much of the pay gap between men and women with PhDs comes about because women tend to pursue degrees in less lucrative fields, a new analysis has found. But even after controlling for field of study, women still earned an average of 11% less than men in their first year. That difference emerged because married women with children earned significantly less than their counterparts. Unmarried, childless women earned the same annual salary as men with a PhD in the same field. The analysis, by Bruce Weinberg of the Ohio State University in Columbus and his colleagues, examined about 1200 graduates of PhD programs in the US. The analysis did not identify any specific factors explaining why married women with children earn less than their colleagues.
New York Times: Donald Trump's comments about climate change and energy policy, until now mostly restricted to Twitter, suggest he does not accept global warming. A briefing prepared by Representative Kevin Cramer (R-ND) for Trump has provided a bit more insight on Trump's potential plans for energy policy. In the briefing, Cramer suggests that Trump could eliminate a federal rule to protect waterways and wetlands, an EPA regulation setting methane emissions standards, and the Clean Power Plan. Describing the briefing in an interview, Cramer said that any energy policy would incorporate all forms of energy, without punishing coal, oil, and natural gas production. Further details are expected in a speech by Trump at an oil conference on Thursday. Both Republicans and environmental groups are concerned over Trump's unclear position.
NPR: In 1965 NIST in Gaithersburg, Maryland, built a machine that uses a stack of stainless steel plates to apply up to 1 million pounds (4.4 million N) of force to test materials' physical properties. It was then, and still is, the largest machine of its kind in the world. Over the past year-and-a-half, the machine underwent refurbishment for the first time. The weights, which accumulated damage over the years, were repaired, and the entire machine was taken apart and then put back together and recalibrated. Earlier this month the machine returned to operation and is working through a backlog of measurement requests.
New Scientist: Asteroids and comets more than 1 km across could devastate Earth if they were to hit the planet. However, Desireé Cotto-Figueroa of Arizona State University in Tempe and her colleagues say that we may not have as much to worry about from asteroids as we thought. Cotto-Figueroa's team tested centimeter-sized cubes from meteorites recovered on the ground. By crushing the samples, the researchers found that the asteroids were nearly as brittle as concrete, which means they are much weaker than most Earth rocks. The researchers extrapolated their measurements of the samples up to much larger scales to calculate the break-up rate for different sizes and types of meteorites. The calculations suggest that rocky asteroids are much more likely to break apart in Earth's atmosphere and turn into a spray of fireballs instead of remaining whole and creating large impacts.
Economist: Each year in the US alone, more than 3500 people—primarily children—swallow button-cell batteries, which can burn holes in the stomach. Removing the batteries generally requires surgery. Now Daniela Rus and Shuhei Miyashita of MIT have developed a magnet-containing robot that can be placed inside a capsule and swallowed. Once the capsule dissolves, the robot unfolds itself and can be moved via magnetic fields from outside the body. After the robot latches onto the battery, the robot tows its haul to the intestine, from which the battery and robot are later excreted. A second robot can then be swallowed and moved to the location where the battery was found to deliver medication that speeds healing of any burns incurred. The team, which tested the robots in a transparent artificial stomach system, now plans to try them out on live pigs, a procedure that will require additional imaging systems to locate the battery and maneuver the robots.
Nature: In the US, the average yearly salary for a postdoc is about $45 000, and many postdocs work much more than 40 hours per week. A new rule finalized by the US Department of Labor, which takes effect on 1 December, will make overtime pay mandatory for many postdoctoral researchers who make less than $47 476 per year. In the US, overtime pay is 1.5 times the normal hourly wage; that rate is triggered when a worker exceeds 40 hours at a single job in a week. Many institutions and funders of postdoc positions will likely opt to increase salaries above the minimum level. However, other positions may get eliminated to compensate. The overtime rule does not apply to postdoctoral positions for which the primary duty is teaching, which means that many humanities postdocs will not benefit.