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Statistical validation of results, as Shaffer described it, simply involves testing the null hypothesis: that the pattern you detect in your data occurs at random. If you can reject the null hypothesis—and science and medicine have settled on rejecting it when there's only a five percent or less chance that it occurred at random—then you accept that your actual finding is significant. The problem now is that we're rapidly expanding our ability to do tests. Various speakers pointed to data sources as diverse as gene expression chips and the Sloan Digital Sky Survey, which provide tens of thousands of individual data points to analyze. At the same time, the growth of computing power has meant that we can ask many questions of these large data sets at once, and each one of these tests increases the prospects than an error will occur in a study; as Shaffer put it, "every decision increases your error prospects." She pointed out that dividing data into subgroups, which can often identify susceptible subpopulations, is also a decision, and increases the chances of a spurious error. Smaller populations are also more prone to random associations. In the end, Young noted, by the time you reach 61 tests, there's a 95 percent chance that you'll get a significant result at random. And, let's face it—researchers want to see a significant result, so there's a strong, unintentional bias towards trying different tests until something pops out. Young went on to describe a study, published in JAMA, that was a multiple testing train wreck: exposures to 275 chemicals were considered, 32 health outcomes were tracked, and 10 demographic variables were used as controls. That was about 8,800 different tests, and as many as 9 million ways of looking at the data once the demographics were considered.

The site that yielded the snake — dubbed Sanajeh indicus, or "ancient-gaped one from India" — was located near a village in Gujarat in western India. It was a rich nesting ground for sauropods known as titanosaurs, with evidence for hundreds of egg clutches, each containing about six to 12 round, spherical eggs. Two other instances of fossil snakes found with these clutches suggest the newly described serpent species made its living plundering nests for young dinosaurs. "It would have been a smorgasbord," said researcher Jason Head, a paleontologist at the University of Toronto at Mississauga. "Hundreds or thousands of defenseless baby sauropods could have supported an ecosystem of predators during the hatching season." The dinosaur eggs likely were laid along the sandy banks of a small, quiet tributary and covered afterward by the mother with a thin layer of sediment. These dinosaurs did not seem to look after their young — no evidence for adults has been found at the site. The fact the bones and delicate structures, such as eggshells and the snake's skull, are arranged in anatomical order (as they would appear in real life) points to quick entombment of a serpent caught in the act, as opposed to them all getting washed together after they died. "Burial was rapid and deep," said researcher Shanan Peters, a geologist at the University of Wisconsin. "Probably a pulse of slushy sand and mud released during a storm."

 »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.

By reworking a theory first proposed by physicists in the 1920s, the researchers discovered a new way to predict important characteristics of a new material before it's been created. The new formula allows computers to model the properties of a material up to 100,000 times faster than previously possible and vastly expands the range of properties scientists can study. "The equation scientists were using before was inefficient and consumed huge amounts of computing power, so we were limited to modeling only a few hundred atoms of a perfect material," said Emily Carter, the engineering professor who led the project. "But most materials aren't perfect," said Carter, the Arthur W. Marks '19 Professor of Mechanical and Aerospace Engineering and Applied and Computational Mathematics. "Important properties are actually determined by the flaws, but to understand those you need to look at thousands or tens of thousands of atoms so the defects are included. Using this new equation, we've been able to model up to a million atoms, so we get closer to the real properties of a substance." By offering a panoramic view of how substances behave in the real world, the theory gives scientists a tool for developing materials that can be used for designing new technologies. Car frames made from lighter, strong metal alloys, for instance, might make vehicles more energy efficient, and smaller, faster electronic devices might be produced using nanowires with diameters tens of thousands of times smaller than that of a human hair.