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Editor’s note (11/16/15): Following the terrorist attacks in Paris on November 13 and the ensuing debate about counterterrorism efforts and encrypted communications, Scientific American is republishing the following article. In the three months since Edward Snowden began his whistle-blowing campaign against the National Security Agency (NSA) the former government contractor has exposed the agency’s massive online eavesdropping efforts and attempts to circumvent encryption used to secure digital communications. The latest allegations indicate the NSA manipulated and weakened a cryptography standard the National Institute of Standards and Technology (NIST) had issued several years ago....

That New Year’s resolution to move more is one of the toughest to keep, and a group of scientists working with obese mice think they’re starting to understand why. Rather than our sedentary lives causing weight gain, says Alexxai Kravitz, the National Institutes of Health neuroscientist who led the study, changes in brain chemistry after we start gaining weight blunt our capacity to move. “Obese mice can move just fine,” says Kravitz, who published the work with his team on Thursday in Cell Metabolism....

STOCKHOLM (Reuters) - Seismic activity at Iceland’s Bardarbunga volcano eased slightly overnight after a series of large quakes and there were still no signs of an eruption, the country’s Met Office said early on Monday. Authorities have been on alert since increased movement at Iceland’s largest volcano system this month triggered memories of the eruption of the Eyjafjallajokull volcano in 2010 that shut down much of Europe’s airspace for six days....

Blood pressure news has set the national media pulse racing. Two weeks ago the National Institutes of Health halted a major clinical trial early because, as The New York Times explained, the study had already “conclusively answered a question cardiologists have puzzled over for decades: How low should blood pressure go?” A lot lower than many doctors had thought, apparently: At-risk older adults who reduced their systolic blood pressure (the top number in the blood pressure ratio) to 120, down from the recommended upper threshold of 140, also dropped their risk for heart attacks, heart failure, strokes and death....

OSLO, Nov 30 (Reuters) - Climate scientists are tracking an erupting volcano on the Indonesian holiday island of Bali for clues about a possible short-cut to curb global warming by injecting sun-dimming chemicals high above the Earth. Volcanoes are emerging as natural laboratories to mimic “geo-engineering”, the idea that governments could deliberately add a veil of sulphur dioxide high above the planet as an artificial sunshade to curb man-made global warming....

The long-standing quest to find a material that can conduct electricity without resistance at room temperature may have taken a decisive step forward. Scientists in Germany have observed the common molecule hydrogen sulfide superconducting at a record-breaking 203 kelvin (–70 C) when subjected to very high pressures. The result confirms preliminary findings released by the researchers late last year, and is said to be corroborated by data from several other groups....

As Olympians go for the gold in Vancouver, even the steeliest are likely to experience that familiar feeling of “butterflies” in the stomach. Underlying this sensation is an often-overlooked network of neurons lining our guts that is so extensive some scientists have nicknamed it our “second brain”. A deeper understanding of this mass of neural tissue, filled with important neurotransmitters, is revealing that it does much more than merely handle digestion or inflict the occasional nervous pang....

The rampant spread of technology-mediated learning has set off fits of hype and hand-wringing—yet the U.S.’s traditional centers of higher education have mostly failed to confront the pace of change and the implications for students. There is probably no way anyone can keep up with this transformation: the technology is simply evolving too rapidly. Nevertheless, we keep trying. Will these developments truly serve our goals for advanced education? We need to know urgently....

Taste is not what you think. every schoolchild learns that it is one of the five senses, a partner of smell and sight and touch, a consequence of food flitting over taste buds that send important signals—sweet or bitter, nutrient or poison?—to the brain. Were it so simple. In the past decade our understanding of taste and flavor has exploded with revelations of the myriad and complex ways that food messes with our consciousness—and of all the ways that our biases filter the taste experience....

Editor’s Note: This article first appeared in Spektrum der Wissenschaft, Scientific American’s sister publication, as “Digitale Demokratie statt Datendiktatur.” “Enlightenment is man’s emergence from his self-imposed immaturity. Immaturity is the inability to use one’s understanding without guidance from another.” —Immanuel Kant, “What is Enlightenment?” (1784) The digital revolution is in full swing. How will it change our world? The amount of data we produce doubles every year. In other words: in 2016 we produced as much data as in the entire history of humankind through 2015....

When I was a veterinary student years ago, I sometimes found a big orange cat sunning himself on my front porch at the end of my workday. He always ambled away as soon as he saw me—not a panicked dash, because he was used to humans—but he certainly was not going to let me get close enough to pet him. No one owned this cat, although my next-door neighbors sometimes fed him, and he clearly lived in the neighborhood; he and my dogs knew one another well, interacting loudly across the fence....

When searching for clues about the physics of the early universe, one has to aim high—and a balloon-borne telescope array known as Spider, set to soar over Antarctica this winter, may succeed where a highly publicized ground-based experiment fell short. Physicists working on that earthbound experiment, known as BICEP2, announced several months ago that they had found evidence for primordial gravitational waves—ripples in the fabric of space itself, dating back to the universe’s earliest moments....

Viruses can be thought of as hyperspeed shape-shifters, organisms that can adapt quickly to overcome barriers to infection. But recent research has been finding ancient traces of many viruses in animal genomes, DNA insertions that have likely been there for much longer than the viruses were previously thought to have existed at all. A new study describes evidence of a hepadnavirus (a virus group that includes hepatitis B, which infects humans as well as other mammals and ducks) hiding in the genomes of modern songbirds....

CRISPR is best known as being the basis of a powerful gene-editing tool. But first and foremost, it is a defense that bacteria use against viruses. Inspired by this delicate natural system, researchers have now created another scientific application for it—a tiny “tape recorder” that chronicles biological signals on strands of a bacterium’s DNA. The investigators believe this microbial recorder could eventually be used for sensing abnormalities in bodily functions such as digestion, for measuring pollutant levels in oceans or for detecting nutrient changes in soil....

President-elect Joe Biden’s transition team says the Trump administration has done more damage than anticipated to the government’s ability to address climate change. Potentially lowering expectations for the incoming president’s early climate efforts, Biden officials say their agency review teams have found deeper budget cuts, wider staff losses and more systematic elimination of climate programs and research than they realized. Some climate moves can’t happen until Biden officials remedy those deficiencies, a senior transition official said, because “those have been very carefully directed budget cuts to the very parts of the [EPA] that are going to be necessary to get rid of [Trump’s] outrageous rollbacks....

Science has a stark message for us all. In this decade, we could lose the fight for the Paris Agreement climate goals, with profound consequences for life on Earth, now and in the future. On our current emissions trajectory—with global heat-trapping emissions continuing to rise except for a brief dip due to last year’s economic crisis—we’re at grave risk of doing so. Global average temperatures keep increasing too, with 2020 ending the hottest decade on record....

In her widely celebrated 1978 book Illness as Metaphor Susan Sontag wrote that when medical experts attribute psychological causality to biological disease, they “assign to the luckless ill the ultimate responsibility both for falling ill and for getting well.” The latest salvo in the ongoing debate over the extent to which psychological factors can explain physiological outcomes comes from a study published today, which finds optimistic women are less likely to die of a variety of illnesses—from cancer to heart failure to infectious disease....

The origins of language have long been a mystery, but mounting evidence hints that our unique linguistic abilities could have evolved from gestural communication in our ancestors. Such gesturing may also explain why most people are right-handed. Researchers at the Yerkes National Primate Research Center recently ex­am­ined captive chimpanzees and found that most of them predominantly used their right hand when communicating with one another—for example, when greeting another chimp by extending an arm....

Ever since Japan’s battered Fukushima Daiichi reactor complex began emitting radiation in March, calls to abandon nuclear power have risen in the U.S. and Germany, among other countries. If only it were so simple. Nuclear contributes 20 percent of the U.S. power supply and a significant share in other developed countries. If we gave it up, what would replace it? Pollution from fossil-fueled power plants shortens the life span of as many as 30,000 Americans a year....

Key Concepts Electric Charge Polarity Attraction Repulsion Introduction Have you ever felt a shock when you tap someone on the shoulder or touch a car door? How about seen sparks when you comb your hair or rubbed a fleece blanket on a cold day? If you have, then you’ve felt the effects of static electricity! In this activity you’ll learn how to use static electricity to make bits of paper jump up and down....