"As the legs unfurl to power the jump," Burrows says, "both have to move at exactly the same time. If they didn't, the animal would start to spiral out of control." Larger animals, whether kangaroos or NBA players, rely on their nervous system to keep their legs in sync when pushing off to jump—using a constant loop of adjustment and feedback. But for the issus, their legs outpace their nervous system. By the time the insect has sent a signal from its legs to its brain and back again, roughly 5 or 6 milliseconds, the launch has long since happened. Instead, the gears, which engage before the jump, let the issus lock its legs together—synchronizing their movements to a precision of 1/300,000 of a second.

A team of Japanese and German researchers have carried out the largest-ever simulation of neural activity in the human brain, and the numbers are both amazing and humbling. § The hardware necessary to simulate the activity of 1.73 billion nerve cells connected by 10.4 trillion synapses (just 1 percent of a brain’s total neural network) for 1 biological second: 82,944 processors on the K supercomputer and 1 petabyte of memory (24 bytes per synapse). That 1 second of biological time took 40 minutes, on one of the world’s most-powerful systems, to compute.

Thank the Maillard reaction (which occurs when the surface temperature of food is more than 300 degrees Fahrenheit) and caramelization (which kicks in at about 320 F). These chemical reactions not only bring about a color change, they also produce hundreds of flavor compounds that create the rich, savory notes and appetizing aromas we associate with roasted, grilled, and seared dishes—notes and aromas that are noticeably absent from foods cooked by wet methods like steaming, boiling, and poaching.

Scientists had struggled to find the trigger for so-called Colony Collapse Disorder (CCD) that has wiped out an estimated 10 million beehives, worth $2 billion, over the past six years. Suspects have included pesticides, disease-bearing parasites and poor nutrition. But in a first-of-its-kind study published today in the journal PLOS ONE, scientists at the University of Maryland and the US Department of Agriculture have identified a witch’s brew of pesticides and fungicides contaminating pollen that bees collect to feed their hives. The findings break new ground on why large numbers of bees are dying though they do not identify the specific cause of CCD, where an entire beehive dies at once.

People often think that the big city is a dangerous place: they worry that they might get murdered, for instance. Being killed on purpose is more likely in town, according to new research, but it is so rare compared to dying in an accident of some type that in fact you would be much more likely to die unexpectedly in the countryside - in America, anyway.

I studien har man undersökt 27.000 män mellan 45 och 82 år under sexton års tid. Den visar att även om man räknar bort faktorer som fysisk aktivitet, sömn, matvanor och vikt så ökar risken dö i hjärtinfarkt eller någon annan hjärtsjukdom med 27 procent om man hoppar över frukosten.

In the study, 10 untrained Goffin’s cockatoos faced a puzzle box showing a nut behind a transparent door secured by a series of five different interlocking devices, each one jamming the next along in the series. To retrieve the nut the birds had to first remove a pin, then a screw, then a bolt, then turn a wheel 90 degrees, and then shift a latch sideways. § One bird, called Pipin, cracked the problem unassisted in less than two hours, and several others did it after being helped either by being presented with the series of locks incrementally or being allowed to watch a skilled partner doing it.

In this post I will describe one small but important part of the theory of causal inference, a causal calculus developed by Pearl. This causal calculus is a set of three simple but powerful algebraic rules which can be used to make inferences about causal relationships. In particular, I’ll explain how the causal calculus can sometimes (but not always!) be used to infer causation from a set of data, even when a randomized controlled experiment is not possible. Also in the post, I’ll describe some of the limits of the causal calculus, and some of my own speculations and questions.

We study fifteen months of human mobility data for one and a half million individuals and find that human mobility traces are highly unique. In fact, in a dataset where the location of an individual is specified hourly, and with a spatial resolution equal to that given by the carrier's antennas, four spatio-temporal points are enough to uniquely identify 95% of the individuals. We coarsen the data spatially and temporally to find a formula for the uniqueness of human mobility traces given their resolution and the available outside information. This formula shows that the uniqueness of mobility traces decays approximately as the 1/10 power of their resolution. Hence, even coarse datasets provide little anonymity. These findings represent fundamental constraints to an individual's privacy and have important implications for the design of frameworks and institutions dedicated to protect the privacy of individuals.

The levels of exposure to radiation following the leaks and explosions at the earthquake-damaged Fukushima Daiichi nuclear power station in 2011 were so low that they led today to this important conclusion from experts convened in Vienna by the United Nations Scientific Committee on the Effect of Atomic Radiation: It is unlikely to be able to attribute any health effects in the future among the general public and the vast majority of workers.

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