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This week, researchers reported evidence of a cosmic impact at classic Clovis archaeological sites. Biologists in Texas discovered a rare hybrid bird, the offspring of a blue jay and a green jay. And a suggests that low-dose aspirin halves the risk of recurrence after surgery for colon and rectal tumors with a particular genetic alteration.

All that, plus a fast new method to verify quantum computer results; the daily alcoholic consumption of chimpanzees (it's higher than you might think); and the mechanism behind exercise-induced weight loss:

Multidimensional checksum

Conventional analog computers are based on binary bits that represent either "1" or "0." Quantum computers use the superstate of particles to achieve multidimensional bits that exist simultaneously in multiple states. There are a range of problems that would take conventional computers millions of years to solve that could theoretically be calculated in seconds or minutes by a quantum computer. But once you've got that output, how do you determine whether it's correct? Using conventional computing to verify the results of a quantum calculation could take millions or billions of years.

Researchers at Swinburne University of Technology have developed new methods to validate the output of a specific type of quantum computer called a gaussian boson sampler, which uses photons to compute probabilities. Using their methods with a conventional laptop computer, the researchers were able to validate the results of an experiment that would take 9,000 years of calculation on contemporary supercomputers.

Researcher Alexander Dellios says, "A vital component of [quantum computing] is scalable methods of validating quantum computers, which increase our understanding of what errors are affecting these systems and how to correct for them, ensuring they retain their 'quantumness.'"

Making every hour happy hour

Fruit drops from a tree, hits the ground and over time, its sugars ferment into alcohol. What are you going to do? Not eat it? Chimpanzees do indeed eat fermented fruits, and over the course of an average day, likely consume a minimum of 14 grams of pure alcohol, according to a new study by researchers at the University of California-Berkeley.

They looked at 21 types of fruit at two chimpanzee study sites in Uganda and the Ivory Coast; fermented samples had an average alcohol content of .26%/wt. The chimpanzees who live in these sites eat an average of 10 pounds of fruit per day. Accounting for the approximate proportion of each fruit species in the chimpanzee diet, the researchers calculate that they consume the equivalent of two standard alcohol drinks per day. But this may be a low estimate.

Biologist Robert Dudley says, "If the chimps are randomly sampling ripe fruit ... then that's going to be their average consumption rate, independent of any preference for ethanol. But if they are preferring riper and/or more sugar-rich fruits, then this is a conservative lower limit for the likely rate of ethanol ingestion."

Exercise validated

Researchers at Baylor College of Medicine have uncovered a mechanism that causes weight loss in response to exercise. When you—or a mouse, or a racehorse—exercise, blood levels of a metabolite called Lac-Phe rise. Lac-Phe causes appetite suppression, leading to weight loss. In previous work, the researchers discovered that giving Lac-Phe to obese mice induced weight loss. In the , they identified how it works.

That mechanism is in the brain, specifically in two types of brain cells: One is called AgRP and the other is PVH. AgRP neurons in the hypothalamus stimulate hunger. PVH neurons in another hypothalamus region suppress hunger. Under normal conditions, AgRP neurons send signals that inhibit PVH neurons, thereby inducing hunger. When AgRP neurons are deactivated, PVH neurons become more active and reduce appetite. Lac-Phe directly inhibits AgRP neurons, thereby activating PVH neurons.

In mice, this caused weight loss. The researchers report that mouse behavior remained normal throughout the experiment, suggesting that there are no unpleasant side-effects of this exercise-induced appetite suppression.