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In his new book, "The Double Helix and the Law of Evidence" (Harvard University Press), Kaye focuses on the intersection of science and law, and emphasizes that DNA evidence is merely information. "There's a popular perception that with DNA, you get results," Kaye said. "You're either guilty or innocent, and the DNA speaks the truth. That goes too far. DNA is a tool. Perhaps in many cases it's open and shut, in other cases it's not. There's ambiguity."

One of the book's key themes is that using science in court is hard to do right. "It requires lawyers and judges to understand a lot about the science," Kaye noted. "They don't have to be scientists or technicians, but they do have to know enough to understand what's going on and whether the statements that experts are making are well-founded. The lawyers need to be able to translate that information into a form that a judge or a jury can understand." Kaye also believes that lawyers need to better understand statistics and probability, an area that has traditionally been neglected in law school curricula. His book attempts to close this gap in understanding with several sections on genetic science and probability. The book also contends that scientists, too, have contributed to the false sense of certainty, when they are so often led by either side of one particular case to take an extreme position. Scientists need to approach their role as experts less as partisans and more as defenders of truth. Aiming to be a definitive history of the use of DNA evidence, "The Double Helix and the Law of Evidence" chronicles precedent-setting criminal trials, battles among factions of the scientific community and a multitude of issues with the use of probability and statistics related to DNA. From the Simpson trial to the search for the last Russian Tsar, Kaye tells the story of how DNA science has impacted society. He delves into the history of the application of DNA science and probability within the legal system and depicts its advances and setbacks.

By combining a hurricane model and coupled ocean-atmosphere general circulation model to investigate the early Pliocene, Emanuel, Brierley and co-author Alexey Fedorov observed how vertical ocean mixing by hurricanes near the equator caused shallow parcels of water to heat up and later resurface in the eastern equatorial Pacific as part of the ocean wind-driven circulation. The researchers conclude from this pattern that frequent hurricanes in the central Pacific likely strengthened the warm pool in the eastern equatorial Pacific, which in turn increased hurricane frequency — an interaction described by Emanuel as a “two-way feedback process.”�The researchers believe that in addition to creating more hurricanes, the intense hurricane activity likely created a permanent El Nino like state in which very warm water in the eastern Pacific near the equator extended to higher latitudes. The El Nino weather pattern, which is caused when warm water replaces cold water in the Pacific, can impact the global climate by intermittently altering atmospheric circulation, temperature and precipitation patterns.The research suggests that Earth’s climate system may have at least two states — the one we currently live in that has relatively few tropical cyclones and relatively cold water, including in the eastern part of the Pacific, and the one during the Pliocene that featured warm sea surface temperatures, permanent El Nino conditions and high tropical cyclone activity.Although the paper does not suggest a direct link with current climate models, Fedorov said it is possible that future global warming could cause Earth to transition into a different equilibrium state that has more hurricanes and permanent El Nino conditions. “So far, there is no evidence in our simulations that this transition is going to occur at least in the next century. However, it’s still possible that the condition can occur in the future.”�Whether our future world is characterized by a mean state that is more El Nino-like remains one of the most important unanswered questions in climate dynamics, according to Matt Huber, a professor in Purdue University’s Department of Earth and Atmospheric Sciences. The Pliocene was a warmer time than now with high carbon dioxide levels. The present study found that hurricanes influenced by weakened atmospheric circulation — possibly related to high levels of carbon dioxide — contributed to very warm temperatures in the Pacific Ocean, which in turn led to more frequent and intense hurricanes. The research indicates that Earth’s climate may have multiple states based on this feedback cycle, meaning that the climate could change qualitatively in response to the effects of global warming.

GPS jammers send out a radio signal that’s the same frequency as the satellite signal. Since GPS satellite signals are weak, a GPS jamming device that puts out approximately 2 watts is sufficient to disrupt a GPS signal in a vehicle that’s approximately within 10 feet of the device. This leaves the in-vehicle system unable to establish its position and report back to a GPS tracking center, where the vehicle is registered. There are also fears that terrorists can use these devices to disrupt air traffic and cause severe safety and economic damage to the US. More powerful jammers could disrupt GPS signals in close proximity of airports, causing safety concerns. Our military overseas use GPS extensively to record their position as well as the position of the enemy. With GPS jamming devices in the hands of our enemy, U.S. and allied forces can be severely impacted when launching ground and air-strikes.

Scanning electron micrograph of the nanofossil Chiasmolithus from about 60 million years ago. This genus arose after the Cretacious Paleogene boundary mass extinction. The size about 8 microns.

The darkness caused by the collision would impair photosynthesis and reduce nannoplankton reproduction. While full darkness did not occur, the effects in the north would have lasted for up to six months. However, with ample sunlight and large amounts of nutrients in the oceans, the populations should have bounced back, even in the North, but they did not. The researchers suggest that toxic metals that where part of the asteroid, heavily contaminated the Northern oceans and were the major factor inhibiting recovery. "Metal loading is a great potential mechanism to delay recovery," said Bralower. "Toxic levels in the parts per billions of copper, nickel, cadmium and iron could have inhibited recovery." On the one hand, the researchers considered an impact scenario causing perpetual winter and ocean acidification to explain the slow recovery, but neither explains the lag between Southern and Northern Hemispheres. Trace metal poisoning, on the other hand, would have been severe near the impact in the Northern Hemisphere. When the high temperature debris from the impact hit the water, copper, chromium, aluminum, mercury and lead would have dissolved into the seawater at likely lethal levels for plankton. Iron, zinc and manganese -- normally micronutrients -- would reach harmful levels shortly after the impact. Other metal sources might be acid-rain leached soils or the effects of wildfires. Metals like these can inhibit reproduction or shell formation. The toxic metals probably exceeded the ability of organic compounds to bind them and remove them from the system. Because nannoplankton are the base of the food chain, larger organisms concentrate any metals found in nannoplankton making the metal poisoning more effective. With the toxic metals remaining in the oceans and the lack of sunlight, the length of time for recovery might increase.

The researchers, led by professor of applied and engineering physics Harold Craighead, made a device just 200 nanometers thick and a few microns long with an oscillating cantilever hanging off one end. (A nanometer is one-billionth of a meter; a micron is one-millionth of a meter.) They identified exactly how to tune its sensitivity -- a breakthrough that could lead to advanced sensing technologies. The experiments detailed online Feb. 8 in Journal of Applied Physics show how these oscillators, which are nanoelectromechanical systems (NEMS), could one day be made into everyday devices by lining up millions of them and treating each cantilever with a certain molecule. "The big purpose is to be able to drive arrays of these things all in direct synchrony," said first author Rob Ilic, a research associate at the Cornell NanoScale Science and Technology Facility. "They can be functionalized with different chemistries and biomolecules to detect various pathogens -- not just one thing."