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Nearly 60 years ago computer scientist Ruth Weiss of Bell Labs published a pioneering algorithm to turn three-dimensional objects into two-dimensional drawings from any angle. But she ran into a problem with depicting outlines—an issue that has remained a computational geometry riddle for decades. With the ubiquity of computer animation today, this “hidden line problem” is now even more pressing. The trickiest part of rendering a 3-D model in 2-D, a crucial step in computer animation, is the deceptively simple matter of the contour: the 2-D visual outline of the 3-D object....

Discoveries of extreme life here on Earth often provoke speculation about what might lurk in other worlds. And so it was, when I reported on January 21 that fish were found living in an isolated corner of the ocean beneath 740 meters of ice in Antarctica: People asked what this might mean for finding life on distant worlds such as Europa, a moon of Jupiter that very likely harbors an ocean of liquid water beneath a crust of ice....

Dear EarthTalk: What are the primary environmental concerns in the aftermath of the big earthquake in Haiti? —Frank Dover, Portland, Ore. As would be the case after any natural disaster, water-borne illness could run rampant and chemicals and oil could leak out of damaged storage facilities as a result of the magnitude 7.0 earthquake that ripped apart Haiti on January 12. Surprisingly, no large industrial spills have been found during initial post-quake rescue efforts, but of course the focus has been on saving human lives and restoring civil order....

The immune systems of men and women respond very differently to infection—and scientists are taking notice. Research presented last week at a microbiology meeting in Boston, Massachusetts, suggests that the split could influence the design of vaccination programmes and lead to more targeted treatment of illness. Hints that men and women deal with infection differently have been around for some time. In 1992, the World Health Organization hastily withdrew a new measles vaccine after it was linked to a substantial increase in deaths of infant girls in clinical trials in Senegal and Haiti....

By analyzing satellite images, oceanographers have found that small oil spills in the heavily drilled northern Gulf of Mexico are often much larger than reported. The researchers presented their results last week at the Gulf of Mexico Oil Spill and Ecosystem Science Conference in New Orleans, Louisiana. Small oil spills — ranging from oil-drilling mishaps to ships discharging fuel — occur with surprising regularity, and tend to escape the public’s attention that follows big spills....

Alan Eugene Miller, who killed three men in workplace shootings in 1999, was scheduled to be the first person executed by nitrogen hypoxia—a new method never before used for the death penalty—on September 22. But a week before his execution, the state of Alabama admitted it was not prepared to go forward with the procedure and would use lethal injection instead. On September 19 the U.S. District Court for the Middle District of Alabama issued a preliminary injunction barring the state from killing Miller by any means other than nitrogen hypoxia, essentially amounting to a stay of execution until the state was ready to administer the new method....

“Women and lowly men are so hard to handle. If you let them too close to you, they become disobedient. But if you keep them at a distance, they become resentful,” Confucius is quoted as saying in the Analects, a collection dating back to the fifth century B.C. Confucius did not invent gender bias, of course, nor did he devise its systemic expression in patriarchy. But the answer to when the concentration of social power in men first arose, and why, may lie in the bones of his ancestors....

Human activity was responsible for two-thirds of glacial melt, which increased sea levels by 69 millimeters across the world in the past two decades, according to a new study published in Science yesterday. The rest of the observed glacial melt was due to natural causes. This is the first time scientists have attributed a certain portion of the glacial melt and the resulting sea-level rise to humans. As such, the study is a landmark as well as a preliminary effort; the scientists are just 85 percent confident of their values....

EASING KIDS’ STRESS Kudos for the special report on “How to Raise a Happy Child.” Authors Jerry Bubrick, Ingrid Wickelgren and Emily Laber-Warren do an excellent job of explaining the intrapersonal and interpersonal dynamics between parents and children with fragile emotions and challenging behaviors. I plan to use these articles to jump-start discussions among school psychologists in various programs for which I consult. As a pediatric clinical neuropsychologist who has written about the impact of stress on learning (in particular, for kids with attention-deficit/hyperactivity disorder and learning disorders), I believe that most, if not all, of the behaviors addressed in the programs described are caused by the predictable reaction of a child who is under stress....

From Quanta Magazine (find original story here). String theory was devised as a way to unite the laws of quantum mechanics with those of gravity, with the goal of creating the vaunted “theory of everything.” Subir Sachdev is taking the “everything” literally. He’s applying the mathematics of string theory to a major problem at the other end of physics — the behavior of a potentially revolutionary class of materials known as high-temperature superconductors....

The following essay is reprinted with permission from The Conversation, an online publication covering the latest research. Should you always do what other people tell you to do? Clearly not. Everyone knows that. So should future robots always obey our commands? At first glance, you might think they should, simply because they are machines and that’s what they are designed to do. But then think of all the times you would not mindlessly carry out others’ instructions—and put robots into those situations....

It hasn’t been this hot in the Southwest in June for 110 years. Sure, the mercury got close to Sunday’s record in 1994, but the last time it was this hot in California was in 1902, in a little town called, appropriately enough, Volcano. The National Weather Service officially declared Sunday (June 30) the hottest June day in the United States ever, at 129 degrees Fahrenheit (54 degrees Celsius) in Death Valley, tying the record from 1902....

Adult jumping spiders are littler than a fingernail, but their vision is as clear as a small dog’s. And the babies, with heads a hundredth the size of their parents’, may see in almost as much clarity. Researchers have now discovered a mechanical secret behind this remarkable hatchling ability. “Even arachnophobic people find these little jumping spiders to be compelling—they dance, they sing vibratory songs to each other,” says Nathan Morehouse, a co-author of the study published in July in Vision Research....

Tim Peake of the European Space Agency completed the 2016 London Marathon on Sunday (April 24), running the 26.2 miles (42.2 km) while circling the Earth about two and half times at an altitude of 250 miles (400 km) high. Peake, who traded the traditional course around the River Thames for a treadmill on the International Space Station, crossed the finish line after three hours, 35 minutes and 21 seconds. [Most Extreme Human Spaceflight Records of All Time] “Running the fastest marathon in space on the only day off from his grueling schedule is a fantastic accomplishment,” stated Marco Frigatti, head of records for Guinness World Records....

SHANGHAI—China has a long and successful track record of scaling up its industrial growth by hitching it to a continent-size home market. This strategy turned China’s wind turbine sector from barely existent to a global leading force in five years. But when it comes to clean cars, the story appears to be different. A program designed to boost China’s transition to electric cars and plug-in hybrids has been stymied. Even with generous government support, cities here have added fewer cars than promised....

Over the last 30 years, the number of twin births has nearly trebled. This rise seems to have followed the introduction of in vitro fertilization and a preference for having children later in life. But in the mid-1990s, doctors began limiting the number of embryos transferred in the course of in vitro fertilization and still the proportion of twin births rose. Now new research seems to show that bovine growth hormone in the food supply may be responsible....

By Declan ButlerLascaux, a cave in southwestern France that holds a dazzling gallery of ice-age paintings, is under siege again. Recent blunders in conservation efforts at the cave have altered its microclimate, and its paintings are again threatened by fungi. But with this month marking the 70th anniversary of the cave’s discovery, scientists are hoping that a newly independent scientific board and fresh management will bring a more robust, research-based approach to conserving the fragile, 18,000-year-old rock art....

We hear every day about the need to conserve freshwater. That goal seems sensible—although knowing if humankind is making any progress could be impossible without a reliable way to quantify how much water nations use. To find out, engineers Arjen Hoekstra and Mesfin Mekonnen at the University of Twente in the Netherlands calculated the water footprint of the world’s countries as well as per capita water consumption in those nations....

In an age when hacking increasingly threatens national security and private companies alike, the possibility of quantum computing looks more and more attractive. By harnessing the special properties of atoms and subatomic particles ruled by the laws of quantum mechanics, physicists hope to design quantum computers that can calculate at speeds unheard of for today’s machines that would enable a whole new type of cryptography. The promise of quantum computers offers a double-edged sword, however, argues quantum scientist Michele Mosca of the Institute for Quantum Computing at Perimeter Institute for Theoretical Physics in Ontario, because such computers could likely crack most conventional cryptography easily, but also create their own unbreakable codes....

Federal health officials said Thursday they are reconsidering a moratorium on the funding of research in which human tissues are transplanted into early, nonhuman embryos—creating organisms known as chimeras. The proposed rule changes, which the National Institutes of Health announced in a blog post, would allow the agency to pay for experiments that incorporate human tissue into early-stage animal embryos, except for those of primates like monkeys and chimps. The NIH put a moratorium on funding early-stage embryonic chimeras in September because of ethical concerns....