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Key concepts Chemistry Acids Bases Maillard reactions Introduction When we put toast in the toaster or add marshmallows to the top of our sweet potatoes for a baked holiday dish we expect them to turn brown and to develop a sweet, caramelized flavor. Although we expect it to happen, do you know why certain foods take on these new colors and flavors as they are toasted? In this activity you will explore the reaction that creates these tasty, toasty treats and experiment with speeding up and slowing down the process....

Longer wind turbine blades over the last decade have allowed wind developers to produce more power without making turbines taller and could continue to drive future growth in the industry. But it may not do much to placate locals who are upset about the increasing visibility of those turbines. The increase in average blade size is a main determinant of what scientists refer to as a turbine’s “swept area”—essentially, the size of the circular path traveled by the blades....

Efforts to drastically slash automobile emissions and fuel use within 40 years don’t stand a chance without subsidies, technology improvements and more stringent government standards, according to a report by a panel of experts released Monday. Congress in 2010 directed the National Research Council to assess the feasibility of reducing both gasoline use and greenhouse gas emissions in cars and light trucks by 80 percent by 2050. The council concluded that goal would be “extremely challenging....

Ocean oddities called mixoplankton are organisms that can get energy both through photosynthesis and by eating other microbes. Now new research published in Nature Communications suggests that one such species, Prorocentrum cf. balticum, displays a bizarre and clever hunting technique—one that significantly contributes to the crucial cycling of carbon through land, atmosphere and oceans. Study lead author Michaela Larsson, a marine biologist at the University of Technology Sydney, and her colleagues were studying marine mixoplankton in the laboratory when they noticed the creatures twisting and turning as they exuded mucus....

Dear EarthTalk: If train travel is so much less polluting than driving or flying, why are passenger rail options in the U.S. so limited compared to Europe? And is anything being done to shift more travelers over to American rail lines from cars and planes? – Jeffrey Orenstein, Bradenton, Fla. It’s true that train travel is one of the lowest impact ways to get from point to point short of walking, jogging or bicycling....

The proliferation of radio-frequency identification (RFID) devices over the past decade has been nothing short of remarkable. But one of the most sweeping promises of the RFID revolution—that the devices will replace the ubiquitous bar code—has not yet come to pass because of their cost. So researchers have been striving to build RFIDs from a cheaper material: plastic. In 2005 a group of engineers at IMEC, a company based in Leuven, Belgium, overcame a major hurdle by constructing a diode made of pentacene, an organic compound that has semiconducting properties....

As a leading climate scientist, Paola Arias doesn’t need to look far to see the world changing. Shifting rain patterns threaten water supplies in her home city of Medellín, Colombia, while rising sea levels endanger the country’s coastline. She isn’t confident that international leaders will slow global warming or that her own government can handle the expected fallout, such as mass migrations and civil unrest over rising inequality. With such an uncertain future, she thought hard several years ago about whether to have children....

December 1966 Noise “The noises of our daily life have been blamed variously for the high divorce rate, social conflict, indigestion and other organic disabilities, nervous breakdown, high blood pressure, heart failure and even insanity. Most of these allegations arise from overvivid imaginations. Studies of the annoyance effect have been conducted among people living in noisy areas: in central London, near the London airport and in several U.S. cities, some of them near military air bases....

Between 1957 and 1986 Martin Gardner wrote the Mathematical Games column for this magazine, with a total of 297 installments. During that time he became the world’s most prolific and best-known popularizer of recreational mathematics. His fans still revere him as a kind of sorcerer who conjured up an endless feast of puzzles, games and riddles built on mathematical ideas that often turned on counterintuitive twists. He may have lived as he wrote: after visiting Gardner’s office, in the attic of the writer’s home, the late mathematician John Horton Conway remarked that “it was filled with puzzles, games, mechanical toys, scientific curiosities, and a host of other intriguing objects, exactly like a wizard’s den....

Disrupted sleep, lower life satisfaction and poor self-esteem are just a few of the negative mental health consequences that researchers have linked to social media. Somehow the same platforms that can help people feel more connected and knowledgeable also contribute to loneliness and disinformation. What succeeds and fails, scientists say, is a function of how these platforms are designed. Amanda Baughan, a graduate student specializing in human-computer interaction at the University of Washington, studies how social media triggers what psychologists call dissociation, or a state of reduced self-reflection and narrowed attention....

Over the past century, many notable viruses have emerged from animals to cause widespread illness and death in people. The list includes the pathogens behind pandemic influenza, Ebola, Zika, West Nile fever, SARS and now COVID, brought on by the virus SARS-CoV-2. For all of these microbes, the animal species that served as the original source of spillover was hard to find. And for many, that source still has not been conclusively identified....

Editor’s note (4/2/2017): This week marks the 100-year anniversary of the U.S. entry into the First World War. Scientific American, founded in 1845, spent the war years covering the monumental innovations that changed the course of history, from the first tanks and aerial combat to the first widespread attacks with chemical weapons. To mark the centennial, we are republishing the article below and many others. For full access to our archival coverage of the Great War sign up for an All Access subscription today....

Each year hundreds of the best and brightest researchers gather in Lindau, Germany, for the Nobel Laureate Meeting. There, the newest generation of scientists mingles with Nobel Prize winners and discusses their work and ideas. The 2013 meeting is dedicated to chemistry and will involve young researchers from 78 different countries. In anticipation of the event, which will take place from June 30 through July 5, we are highlighting a group of attendees under 30 who represent the future of chemistry....

Remember the first time you asked someone out? Whether it was in middle school or well into adulthood, I bet it was at least a little bit nerve-wracking. What if they say no? Worse, what if they make fun of you or show pity? What if they make it seem like it was ridiculous for you even to ask? These hypothetical nightmare scenarios make even the bravest of us fear rejection....

Most people consider smell their least important sense, surveys suggest. Dogs, however, feel their way through the world with their noses. Humans already employ the animals’ olfactory acuity for contraband and explosives detection. More recently it has also proved uncannily good at sensing cancers, diabetes—and even COVID-19. Exactly how dogs detect diseases is a mystery, but that has not stopped researchers from mimicking this prowess with an artificial-intelligence-based noninvasive diagnostic tool....

U.S. astronaut Gene Cernan, who as the commander of the final Apollo lunar landing mission in 1972 became known as the “last man on the moon,” died on Monday (Jan. 16). He was 82. NASA confirmed Cernan’s death on its website and social media channels, noting he was surrounded by his family at the time he died. The cause of death was not stated, but he was known to have been ill in recent months....

For 6-year-old Macey, lunchtime at school is not so much a break from reading and math as it is an hour rife with frustration. Here’s how Macey’s mother, Victoria, describes Macey’s typical lunch break: In her special-education classroom an hour north of San Francisco, Macey’s classmates gather at a big square table, chattering away and snatching one another’s food. Macey, meanwhile, is sequestered away at a small white table in a corner, facing a bookshelf....

As the world hurtles toward 2 billion cars, an increasingly important issue for the climate will be this: How will China’s citizens get to work? With their rising incomes and access to freshly paved roads, many will be tempted to emulate Americans and buy cars. Some will ride the gleaming rail networks funded by Beijing. But in the past two years, China has also become the world’s fastest-growing market for high-speed city buses....

The US’s rapidly growing cannabis industry—medical and recreational—desperately needs chemists. That was the conclusion of a session at the American Chemical Society’s spring conference in Denver, Colorado, on 23 March. ‘We need chemists to tell us what we have,’ said Chloe Villano, founder of the Colorado-based cannabis business consulting company Clover Leaf. She said a better understanding of the science behind cannabis is essential to providing safer and better products, which include oils, extracts and edibles....

A key ingredient in chili peppers, chased with a local anesthetic, could be just the ticket for ending pain in the dentist’s chair and on the operating table without the potentially dangerous side effects and all-numbing aftermath of traditional anesthesia, says a new Harvard Medical School study. Researchers report in Nature that a combination of capsaicin (the ingredient that gives chili peppers their bite) and QX-314, a derivative of lidocaine (a local anesthetic used by dentists and to relieve inflamed, itchy skin), effectively silences pain-sensing nerve cells without disturbing other neurons that control motor function and other sensations....