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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.

 »We’ll just have to wait for the results of the laboratory tests.« These words are familiar to many patients. It then usually takes several days for specimens to be sent to the laboratory and analyzed and for the doctor to receive the results. For many illnesses, however, a speedy diagnosis is crucial if the treatment is to be successful. In future, the patient might only have to sit in the waiting room for a few minutes until the results are ready. In a joint project, researchers from seven Fraunhofer institutes have developed a modular platform for in vitro diagnosis which enables various types of bioanalysis – of blood and saliva for example – to be conducted in the doctor’s surgery. »Thanks to its modular design our IVD platform is so flexible that it can be used for all possible bioanalytical tasks,« states Dr. Eva Ehrentreich-Förster from the Fraunhofer Institute for Biomedical Engineering (IBMT) in Potsdam-Golm.The core element of the mini-laboratory is a disposable cartridge made of plastic which can be fitted with various types of sensor. For an analysis the doctor fills the cartridge with reagents – binding agents which indicate the presence of certain substances such as antigens in the specimen material. Various tests or assays are available for different types of analysis. To perform an assay, the doctor only has to place the relevant substances in the cartridge and the test then takes place automatically. »We have optimized the assays so that up to 500 assay reactions can be conducted in parallel in a single analysis step,« explains Dr. Ehrentreich-Förster. Even in the case of complex analyses the doctor obtains a result within about 30 minutes. A new module on the reverse side of the cartridge also makes it possible to analyze the specimen material at DNA level.Once the cartridge has been prepared, the doctor places it in the measurement system. The results can be read out with either optical or electrochemical biosensors. The researchers have installed a readout window for both methods in the measurement system, which features a bypass through which the specimen is pumped.

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.