MIT Technology Review: The tissues of the heart possess a set of properties that has been hard to reproduce in the lab. The muscles are mechanically tough and electrically conductive, and they maintain a constant rhythm of motion. Researchers have been growing cardiac cells in various polymers and gels, but the resulting materials don’t have the same level of conductivity or the ability to sustain continued movement. Ali Khademhosseini, of the Harvard–MIT Division of Health Sciences and Technology in Cambridge, Massachusetts, and his colleagues believe they’ve found a solution: adding carbon nanotubes to their gels. The nanotubes are conductive, and their fibrous nature gives the material a great deal of mechanical strength and durability. Before the material can be used for any sort of medical purposes, though, the safety of the carbon nanotubes and of the material in general would have to be demonstrated. But the material could still find uses in biomechanical applications as parts of robots used to explore areas that are toxic or dangerous to humans.
Daily Archives: February 13, 2013
Iran says it has converted enriched uranium into reactor fuel
New York Times: Iran is preparing for two meetings with international negotiators regarding its nuclear energy program. In the face of North Korea’s apparent nuclear weapons test, Foreign Ministry spokesman Ramin Mehmanparast indicated that Iran was in the process of converting some of its weapons-grade uranium into reactor fuel. Iran has been the target of sanctions due to international suspicions that the nation is trying to develop nuclear weapons of its own, and it has rejected requests from the International Atomic Energy Agency (IAEA) to inspect its nuclear facilities. If it is true that Iran has converted uranium into reactor fuel, that uranium can no longer be easily used in nuclear weapons. Some analysts are saying that it may just be a ploy on Iran’s part to keep its weapons-grade stockpiles below a level that might trigger a response by Israel. However, it does not appear that Iran will allow inspectors from the IAEA to visit the Parchin military site, which international inspectors believe is developing nuclear technology.
Satellite shows significant decline of Arctic ice volume in autumn
BBC: The European Space Agency’s Cryosat satellite has collected two years of data on Arctic ice thickness that show a significant decline from previous data. The satellite uses radar to measure the difference in height between the top of the ice and the surface of the water. Scientists then calculate the ice’s total volume. Katharine Giles of University College London and her team compared the data they collected from 2010 to 2012 with similar data collected by NASA’s Icesat from 2003 to 2008. They found that the total volume of ice during the autumn months had decreased by one-third from the previous measurements. The decline during winter months was only 9%, but that was mostly because of the increased area of ice coverage, not an increase in ice thickness. Giles and her team determined that the sea ice north of Greenland and in the Canadian archipelago had lost a significant volume, despite not shrinking much in area. Their findings match well with simulations and independent collections of similar data.
Missouri state legislator tries to redefine science
Ars Technica: State legislatures in the US are responsible for defining the educational curricula of the state school systems. It is not unusual for legislators to introduce bills that would promote criticism of established science such as climate change or evolution. However, a bill presented in the Missouri House of Representatives by Rick Brattin takes science education legislation to a new level. Brattin’s bill begins by redefining several terms: Scientific theory is described as “an inferred explanation of incompletely understood phenomena about the physical universe based on limited knowledge, whose components are data, logic, and faith-based philosophy”; hypothesis is defined as “a scientific theory reflecting a minority of scientific opinion which may lack acceptance because it is a new idea, contains faulty logic, lacks supporting data, has significant amounts of conflicting data, or is philosophically unpopular.” Using those definitions, the bill then explicitly equates the legitimacy of evolution with intelligent design, says that both topics must be given equal time in classrooms, and even mandates that textbooks have an approximately equal number of pages devoted to each. The bill isn’t likely to make much progress in the legislature, but it is an interesting development in the attempt to legislate scientific principles.