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The entries below include some highlights; see “More to Explore” for related references. A fuller bibliography is at www.ifp.uiuc.edu/koetter/NWC/ –M.E., R.K. and M.M. 2000: Concept introduced. In a landmark paper, Rudolf Ahlswede, Ning Cai, Shuo-Yen Robert Li and Raymond W. Yeung showed the potential power of network coding in multicast networks, where all receivers get identical information. They proved that good (informative) codes exist, although they did not describe a method for designing them....

DNA tests have made it clear that many innocent people have been sent to prison after a witness picked them out of a lineup. Between 1989 and 2016, more than 70 percent of the 337 wrongful convictions identified in the U.S. had been influenced by misidentification from eyewitnesses, according to the Innocence Project. Researchers recently reported, however, that a simple procedure could help reduce the risk of misidentification: ask the eyewitnesses about their confidence level whenthey pick someone from a lineup....

If you are like many people, navigating the complexities of everyday life depends on an array of cards and passwords that confirm your identity. But lose a card, and your ATM will refuse to give you money. Forget a password, and your own computer may balk at your command. Allow your cards or passwords to fall into the wrong hands, and what were intended to be security measures can become the tools of fraud or identity theft....

The Road to Relativity: The History and Meaning of Einstein’s “The Foundation of General Relativity” by Hanoch Gutfreund and Jürgen Renn Princeton University Press, 2015 (($35)) Any devotee of Einstein will relish the chance to parse this annotated facsimile of the physicist’s original manuscript on general relativity. The authors provide a full English translation and painstakingly explain, page by page, Einstein’s text and equations, which lay out his theory and the path he took to derive it....

The sky is always changing. The planets move overhead as they trace their paths around the sun, and the moon rotates through the heavens as it circles our own world. Though the stars that provide their backdrop stay fixed in relation to one another, they too spin above as Earth makes its daily revolution and its yearly passage around the sun. To appreciate this ever-changing view, grab these sky maps, go outside at night, and look up!...

DENVER—Suppose you have an idea for a cleaner, simpler and more energy-efficient internal combustion engine for trucks and cars. It was inspired by the engine design for Nazi Germany’s World War II bombers, the last of which—the Amerika—was being built to bomb the United States when the war ended. You scale the engine down so it can fit in a car or a truck and you give your car company an obscure name—Achates Power—derived from Greek and Roman mythology....

Astronomers have filled in more details in the picture of the Milky Way Galaxy, unveiling five previously unknown planets outside our solar system that were detected via early data from NASA’s planet-seeking Kepler spacecraft. A team of researchers reported the planet findings Monday at a meeting of the American Astronomical Society and in a paper to be published online Thursday in Science. Kepler launched in March to seek out worlds like our own—terrestrial planets orbiting sunlike stars at a temperate distance where liquid water could persist....

After people realize the facts have been fudged, they do their best to set the record straight: judges tell juries to forget misleading testimony; newspapers publish errata. But even explicit warnings to ignore misinformation cannot erase the damage done, according to a new study from the University of Western Australia. Psychologists asked college stu­dents to read an account of an ac­cident involving a busload of elderly passengers. The students were then told that, actually, those on the bus were not elderly....

HIV/AIDS is a primary cause of death in sub-Saharan Africa. It is no longer always a death sentence, thanks to lifelong antiretroviral therapy, but getting treatment to patients is a challenge. Now researchers have conducted one of the most geographically specific analyses to date of HIV prevalence in 47 sub-Saharan countries. The study could help authorities better target treatment and prevention efforts. “We hope that it will be useful to people on the ground who are in one particular area and add to what they already know about their community,” says lead author Laura Dwyer-Lindgren, an assistant professor of health metrics sciences at the University of Washington....

One of the biggest fears Joseph E. LeDoux had when he was growing up was of getting stuck in Eunice, La. His small hometown sits among creeks and rice fields, and its Cajun country roots give it a certain charm. It is hard to swing a possum without hitting a good gumbo restaurant. An old theater downtown hosts the weekly Rendezvous des Cajun radio show, a yipping version of Prairie Home Companion, only with dancing, and anyone can join the live studio audience for a mere $5....

Sunlight is speeding up the conversion of Arctic soil carbon into carbon dioxide, raising the possibility that future warming could occur at a much faster pace, according to a new study. Scientists generally agree that higher temperatures increase the likelihood of collapses of long-frozen Arctic ground, or permafrost, creating large holes in the tundra and landslides. But there has been less understanding of how long-buried carbon in the permafrost behaves when suddenly exposed to the sun’s rays after such collapses, which are caused by the melting of ice-rich soils....

SEPTEMBER 7–10 Neuroimaging techniques have revolutionized our understanding of how the brain works. A recent study, for instance, used functional MRI to show that physical and emotional pain, such as feelings of rejection after a breakup, activate the same pathways in the brain. At the four-day International Society for Neuroimaging in Psychiatry conference, researchers will focus on how to use imaging techniques to visualize both normal changes that occur during a person’s life and the effect of age-related diseases, such as schizophrenia or dementia, on brains over time....

The U.S. elected Donald Trump president just two days after United Nations climate talks began in Marrakech, Morocco—a conference meant to turn the December 2015 Paris climate agreement into national action plans. The election results stunned negotiators, and raised questions for everyone at the two-week conference about what a Trump administration means for the agreement, which entered into legal force last week. Still, observers at the 22nd Conference of Parties (COP 22) say the international community remains strongly committed to fighting climate change—with or without Trump’s cooperation....

In the summer of 2012, a series of punishing heat waves roasted a large portion of the U.S. with record-breaking temperatures that helped spawn one of the most widespread and costliest droughts to hit the country in decades. Combined, the blistering temperatures and drought cost some $31.5 billion and led to dozens of deaths. The heat was so intense that it melted roads and airport runways. In May of that year, when the National Oceanic and Atmospheric Administration issued its forecast for the summer, it had predicted normal temperatures for the Midwest and Northeast — a forecast that clearly fell short....

America’s Endangered Species Act—which protects more than 2,000 plant, animal and insect species at risk of extinction—is under renewed attack from Republican politicians. But policy experts say that their efforts face an uphill battle, even though Republicans control the White House and both chambers of Congress. On 19 July, the US Fish and Wildlife Service (FWS) and the National Marine Fisheries Service (NMFS) proposed policy changes that would make it easier to delist species and harder to add new ones, among other things....

By Lisa Rapaport (Reuters Health) - As soccer has soared in popularity in recent decades, injury rates for youth players have also surged, a U.S. study suggests. The injury rate for youth soccer players aged 7 to 17 more than doubled over the 25-year period ending in 2014, according to an analysis of children treated in U.S. hospitals. Even though concussions accounted for just 7 percent of these injuries, the annual rate of concussions surged by almost 1,600 percent during the same period....

There are no gas stations in space. To send affordable, lightweight spacecraft on long-range missions, NASA and several aerospace companies are seeking ways to exploit the power of sunlight. Possibilities include reflective “sails” billowed by the sun’s rays, as well as next-generation solar electric propulsion. In the coming months a privately backed project called LightSail 2 plans to launch a lunch box–size craft into orbit, where it will deploy a Mylar sail about as big as two parking spaces....

From its perch outside the International Space Station (ISS), the Alpha Magnetic Spectrometer (AMS) has spent the past 8.5 years collecting charged cosmic rays that move through space at nearly the speed of light. Unlike particle detectors on Earth, AMS is not attached to an accelerator but instead studies its quarries as they exist in the vacuum of space, unadulterated by interactions with our planet’s atmosphere. The experiment aims to tackle some of the universe’s biggest quandaries, such as what makes up the missing dark matter that seems to dominate the cosmos and why it contains more matter than antimatter....

The long-awaited results from a NASA satellite sent up to test Einstein’s theory of gravity will have to wait a few months longer. Although researchers have spotted one of the two spacetime-bending effects they were looking for with the Gravity Probe B (GP-B) relativity mission, they are still working to pry the second, fainter effect from the data. Researchers gave their colleagues a peek at the analysis this weekend at the annual meeting of the American Physical Society....

T. rex may have been a highly successful predator, but it would have been terrible at licking stamps, lollipops or popsicles, thanks to a tongue that was likely fixed to the bottom of its mouth. A new study calls into question artists’ renditions of T. rex and other dinosaurs that show them with their tongues protruding from gaping jaws—a pose that is commonly seen in modern lizards. But even though lizards are tops at tongue waving, dinosaurs probably couldn’t stick out their tongues, researchers recently discovered....