DiscoverMarch 2019的目錄

A DECADE AGO, Discover explored psychedelics’ potential to heal treatment-resistant psychiatric conditions. The May 2008 story, “Acid Test,” described the efforts of Charles Grob and a handful of other scientists to revitalize research on hallucinogens’ mind-altering properties to restore mental health. Evidence from the 1950s and ’60s suggested hallucinogen-induced mystical experiences could jump-start recovery from substance abuse and alleviate end-of-life angst. That work came to an abrupt halt in the 1970s after Congress banned the drugs to curb widespread recreational use. But a new generation of psychedelic researchers persisted, making “dramatic progress” on the hardest cases, Grob, a psychiatrist at the University of California, Los Angeles, told Discover in 2008. “We’re on the threshold of opening up an exciting new field.” His optimism was well placed. In 2011, Grob showed that…

Although it might not be obvious, a material like lead has multiple magnetic fields, one inside and another on its surface. Until recently, researchers could confidently measure only surface fields. Now, in a recent Nature Communications paper, materials scientists in Germany describe a way to create detailed maps of the direction and strength of magnetic fields inside bulky materials like those used in electric engines and high-efficiency transformers. The new method uses neutrons, neutrally charged subatomic particles that spin in the opposite direction of a magnetic field’s alignment. Because neutrons are so small and chargeless, they easily penetrate many materials. The team took advantage of these properties, scanning a sample of lead with neutrons that all had the same spin. When they hit a magnetic field inside the sample, their…

On a misty autumn morning in Australia’s Royal National Park, just south of Sydney, a peloton of nearly two dozen cyclists tackles a 3,740-foot ascent. When they reach the highest point of the day’s 45-mile ride — the first leg of a weeklong journey — they’re rewarded with cookies and candy from support staff, followed by a downhill glide along a sandstone escarpment. Far below them, waves of the Pacific barrel toward shore and explode in clouds of foam. The group is not training for an athletic event. Instead, the 21 cyclists and their support crew have united to promote an unconventional pain management approach. The team wants to start a revolution. The road ahead is a long one. Australian physical therapist and pain scientist Lorimer Moseley, 48, got the…

Aliens are serious science. The search for extraterrestrial intelligence, or SETI, constitutes major research projects at radio telescopes the world over, and it is championed by the non-profit institute that shares its name. Multiple experiments on the subject, and citizen science projects like SETI@home, have been going strong for decades. Every year, papers, conferences and initiatives discuss how best to seek out — and maybe even talk to — E.T. But it wasn’t always that way. While UFO sightings and depictions in movies and comics spiked during the 1950s, the topic of aliens was considered unprofessional among scientists. Only a handful of professionals would speculate on the possibility of alien life, and even they made sure it was only a small part of their research. So when a group of…

When Alvin arrived at the hospital, he believed he’d been sent there as a doctor working on behalf of the U.S. government. “Which patient do I need to see first?” he asked the triage nurse. Until recently, Alvin had been an ordinary economics graduate student. But somehow he’d become convinced that he was a trailblazing physician who needed to identify a rare strain of tuberculosis before it spread throughout campus. That morning, he arrived at his graduate school classroom with a stethoscope around his neck, a surgical mask over his face and a bag containing more masks and several thermometers. He began to practice medicine on his classmates. At first, his manner and physician attire made them think he was joking, as Halloween was just around the corner. But when…

The greatest mystery of modern radio astronomy comes down to just three letters: FRB. They stand for fast radio bursts, signals that continue to defy explanation. As the name implies, these bursts of radio waves last just a millisecond or two. They’re also incredibly strong, among the brightest radio sources in the sky. That’s despite traveling an incredible distance, up to billions of light-years. Do the math, and it’s clear how powerful these things are. One FRB can easily broadcast more energy in a moment than the sun produces in a day. Visible light is only a part of the electromagnetic spectrum, but if your eyes could see radio waves, you’d probably spot FRBs in the sky all the time — thousands of them a day, from all directions. Despite…

Pain Revolutionaries believe chronic pain can result from an injury oversensitizing the brain. Before the injury, the brain would send out pain cues only if an activity is about to cause actual tissue damage. After the injury, although the tissue may be at risk of reinjury, the threshold for the brain to feel the body is threatened — the protect-by-pain line — is disproportionally lower. BEFORE INJURY Initial tissue tolerance line Initial protect-by-pain line THE ROAD TO RECOVERY New tissue tolerance line Flare-up line Baseline New protect-by-pain line AFTER INJURY New tissue tolerance line New protect-by-pain line 1 For chronic pain sufferers, retraining the brain starts with careful, planned baseline activity. Individuals work above their artificially lowered protect-by-pain threshold, but aren’t at risk of actual tissue damage. 2 Individuals increase…

TWENTY THOUSAND LEAGUES UNDER THE SEA had Nemo’s Nautilus. Voyage to the Bottom of the Sea featured the Seaview. Fantastic Voyage even sent a submarine into the human body at the capable hands of Captain Bill Owens. Fiction often presages fact, and it seems that submarines may turn out to be the new hotness in planetary exploration, although their fearless skippers will remain back on Earth. The solar system is awash with oceans. Unlike the majority of Earth’s seas, these ubiquitous brines are locked away beneath ice crusts. But they’re there, lurking under the surfaces of Ganymede, Europa, Enceladus, and perhaps other worlds like Titan, Dione, and Pluto. These maritime sites may provide the best venues for life beyond Earth, but getting to them is the tricky part. In the…

The number of technologically advanced civilizations in the Milky Way. The rate of star formation in the galaxy. The fraction of those stars that have planetary systems. The number of planets within each solar system that have an environment suitable for life. The fraction of suitable planets that actually are home to life. The fraction of inhabited planets where intelligent life emerges. The fraction of civilizations capable of releasing detectable signs of their existence into space. The length of time such civilizations actually do release detectable signals into space.…

Greenland’s vast Helheim Glacier sprawls before oceanographer David Holland (left) and safety officer Brian Rougeux as they repair a solar panel array last summer. The setup powers a nearby seismometer that detects “icequakes” and helps researchers learn how the ice fractures. It’s part of a land-, sea- and air-based program led by NASA’s Jet Propulsion Laboratory, dubbed Oceans Melting Greenland. The effort will help scientists better understand the effect of rapidly warming deep ocean currents and how they melt Greenland’s coastal ice from below.…

THOMAS GARRISON pauses in the middle of the jungle. “That’s the causeway right there,” he says, pointing into a random patch of greenery in the Guatemalan lowlands. I squint, trying to make out features in the tangled rainforest undergrowth. There’s a small lump, rising no more than a foot or two from the forest floor. The Ithaca College archaeologist has spotted the buried remnants of a Maya road, a ribbon of limestone that once cut through the wrinkled landscape. We’re a full day’s walk from civilization, standing in the remains of a once-populous kingdom. The road before us is just one piece of a vast network leading to terraced fields, reservoirs, defensive fortifications and more, all sprawling invisibly throughout the forest. In the 1,000-plus years since the Maya society collapsed,…

While working with patients early in his career, Moseley observed that the attitudes health care providers displayed, and the language they used, could actually worsen their patients’ discomfort. Terms such as degenerated, desiccated, stuck, bone-on-bone, jammed, out of alignment, locked and twisted can color a patient’s self-perception of pain. Instead of describing pain with such daunting and imprecise language, says Moseley, it should be reframed as a smart, protective mechanism that sometimes goes off the rails. Pain is modulated by context, expectations and experience, so what the practitioner says to the patient makes a big difference.…

When Robert Hooke peered through a primitive microscope in the mid-17th century, he set in motion a revolution. Today’s understanding of the fundamental structure of living organisms began when he examined thin slices of cork and saw tiny walled compartments that looked like a monk’s dwelling: He called them cells. Subsequent advances over the centuries deepened our understanding of these structures, which we now know to be the basic unit of life. In the past decade alone, quantum leaps in technology have enabled scientists to explore the Lilliputian universe of the cells with unprecedented precision. The developments have sparked the creation of a massive scientific juggernaut that rivals the Human Genome Project in scope and importance. Called the Human Cell Atlas (HCA), the international research effort aims to create a…