Innholdsfortegnelse for July/August 2020 i Discover

SQUISHED SKULL Can’t quite make out what you’re seeing here? Look closer. This blur of beige is actually the flattened skull of a Neanderthal, compressed by millennia of sediment and falling rocks. The skull was part of a skeleton unearthed by a team of researchers at Iraq’s Shanidar Cave in 2017 — more than half a century after the skeletal remains of 10 other Neanderthals were found at the site. Those first finds gave scientists a rare glimpse at how our ancient ancestors lived. Among the finds: pollen near the bodies, which led archaeologists to conclude that Neanderthals had burial rites, like putting flowers on their dead. Now, researchers have used modern archaeological techniques to identify rocks placed with the remains, showing that this new find is yet another example…

Steven Jacobsen never planned on becoming a geophysicist. In fact, that might have been the furthest thing from his mind when he started college at the University of Colorado in the early 1990s, intent on majoring in music or business. But after he randomly chose a geology course to meet the school’s science requirement, he was inspired to follow a different path. “After all those days of playing outside as a kid and picking up rocks,” Jacobsen says, “I realized that this is what I wanted to do.” Now, he studies not just rocks, but the water hidden inside them. The more he and other researchers look, the more water they find all throughout Earth’s interior — even though it may not resemble the liquid we’re familiar with. Under the…

Over a century ago, scientists partitioned memory into short-term and long-term categories. Short-term memory, sometimes called working memory, refers to our ability to retain information or events from the recent past — but only for as long as about 20 seconds ago, sometimes even less. In other words, it’s the stuff that you’re actively holding in your head while performing other tasks — for example, remembering a phone number as you scroll around to plug it into your contacts list. In the 1990s, scientists analyzed high-resolution brain scans and found that these fleeting memories depend on neurons firing in the prefrontal cortex, the front part of the brain responsible for higher-level thinking. “They are temporary [memories],” says neuroscientist and author Dean Burnett. “It’s not meant to be for long-term storage,…

When we form episodic memories of things that happened to us, three areas of the brain are engaged: the hippocampus, the neocortex and the amygdala. The hippocampus takes the information from our memories and physically encodes it into the connections between neurons. Later, this data is sometimes transferred to the neocortex — the thin tissue that forms the brain’s outer layer — for long-term storage. But it is the amygdala, an almond-shaped mass of brain matter, that injects our memories with emotions like fear. “If an experience has a strong emotional component, the amygdala will squirt that into the newly forming memory,” says Burnett. “If someone has an active amygdala, they learn to be scared of things.” In recent years, scientists have learned a lot about the hardware in our…

Common risk factors like smoking and diabetes are more potent in women, and researchers are slowly understanding why. One common denominator is the rise in blood pressure, or hypertension, that these factors cause, says Susan Cheng, a cardiologist and population researcher at Cedars Sinai in Los Angeles. In a study published in 2020 in JAMA Cardiology, Cheng’s team analyzed repeated blood pressure data collected over 43 years in people ages 5 to 98. The researchers compared an individual’s blood pressure with their younger selves and tracked those changes over decades. Cheng compared women with women and men with men, something researchers hadn’t done before. The results showed that women’s blood pressure accelerates over their lifetimes faster than it does in men, and that acceleration starts earlier in life. “It was…

How’s your tummy feeling today? Odds are, not that great. A new study estimates that Americans spent $135.9 billion on treatment for gastrointestinal diseases in 2015, over the course of more than 54.4 million trips to the doctor. Irritable bowel syndrome (IBS) alone is thought to affect 10 to 15 percent of all people worldwide, many of whom are undiagnosed. Your digestive system achieves no small feat each and every day, as it turns things you eat into usable energy and nutrients for the rest of your body. It’s an incredibly complex system, which also means there’s incredible complexity in the ways things can get out of whack. But while gut issues are on the rise, so is our understanding of them. Researchers have made huge strides toward figuring out…

A Word of Warning (“Riding in Cars With Dogs,” Mar./Apr. 2020) I was interested to read the piece about dogs in cars, but I would like to offer a word of caution. About a year ago we had a scary moment when our Maremma, Dante, got his head trapped when he managed to hit the window button with his paw. We happened to be stopped at a traffic light at the time, so I was able to race around and wrench the door open to free him. If you are going to let your dog put his or her head out of the window, please be sure to engage the window lock on your vehicle. Mark Haviland, Belgrave, Australia You’ve Entered the Twilight Zone (“Seeking Binary Sunsets,” Mar./Apr. 2020) As…

WE WERE FLYING BLIND. The red alerts flashed from Wuhan to Lombardy to Seattle, yet the first COVID-19 cases in early March in New York City prompted an official reaction that suggested the virus had traveled by asteroid, not by human daisy chain. None of the patients in our emergency department had traveled to China or been around someone diagnosed with COVID-19. There was no clamor to broaden testing, no rush to rethink the model of contagion, no clarion to immediately shut down. Reality hit in stages, like a plane lurching through air pockets. First lurch: Coming onto a shift in mid-March, a colleague informed me, “Yesterday we had a middle-aged guy. Looked pretty good, decent oxygen saturation of 96 percent, then a few hours later, crumped [rapidly declined]. Crash…

The world has been upended in 2020, thanks to the novel coronavirus SARS-CoV-2. At Discover, we’ve been working diligently — from our homes — to continue to bring you the science that matters, so you can separate fact from fiction, make informed decisions and keep yourself and your loved ones safe and well. Here are just a few key things we think you should know during the COVID-19 pandemic. Visit DiscoverMagazine.com for more coverage. — ANNA FUNK HOW THE VIRUS HIJACKS YOUR BODY THE VIRUS THAT causes COVID-19 is transmitted through tiny, invisible droplets sent into the air when an infected person coughs or sneezes. Those droplets can then land on people nearby or surfaces that others touch. From there, these viral particles can pass from people’s hands to their…

There’s no question that human bodies are staggeringly complex and intricate machines, capable of astonishing feats. Even in antiquity, they captivated and mystified scholars and scientists. While we’ve come a long way in the centuries since, for many of us, the body is still shrouded in mystery. At a time when we’re learning just how completely threats to those bodies can disrupt our lives — and a time when the roar of pseudoscience can be deafening — truly understanding how we work may be more essential than ever. In this issue, we aim to provide a window into those workings, focusing on five major categories: the brain, gut, heart, and our muscular and immune systems. As we journey throughout the body, the functions that might seem mundane take on new…

Normally, oxygen flows into the lungs, through the bloodstream and into the heart. But when lungs are badly infected, less oxygen can make it past that first step, and the heart won’t have enough to pump throughout the body. This causes “incredible stress on the heart,” as it works harder and harder to make up for the lack of oxygen, says Peter Gulick, an infectious disease researcher at Michigan State University. “And then it causes people to have heart attacks and heart failure.” Our body’s attempt to fight the virus can wreak havoc on the heart as well. Once the immune system recognizes an invader, white blood cells rush into battle to rid it from the body, causing widespread inflammation responsible for symptoms like fevers and muscle aches. “The inflammatory…

As soon as I felt the plane nose toward Dhaka, Bangladesh, I started preparing. I pulled up my socks, rolled down my sleeves and fished a hat out of my bag. The temperature on the ground was in the upper 80s, but I tried to cover every slice of skin. Anything exposed — hands, neck, ears — got a healthy dose of 100 percent DEET. In the preceding weeks, reports of dengue fever had been mounting in this waterlogged country, and most were coming out of the crowded capital toward which I was descending. The outbreak had developed into the worst dengue epidemic in Bangladeshi history. It was even more dire in other parts of Southeast Asia. More than 91,000 people were infected between January and October 2019, nearly twice…

Impaired Gas Exchange When the immune system attacks the area of infection, it also kills healthy alveolar cells. This results in three things that hinder gas exchange: 1) The alveoli collapse due to loss of surfactant from Type II cells.2) Less oxygen enters the bloodstream.3) More fluid enters the alveolus. Gas Exchange Each sac of air, or alveolus, is wrapped with capillaries where red blood cells release carbon dioxide (CO2) and pick up oxygen (O2). Two types of alveolar cells facilitate gas exchange: Type I cells are thin enough that the oxygen passes right through, and Type II cells secrete surfactant — a substance that lines the alveolus and prevents it from collapsing. Viral Infection The spike proteins covering the coronavirus likely bind to ACE2 receptors on Type II alveolar…

FEW ACTIVITIES swell our carbon footprint quite like flying. A one-hour flight on a twin-engine jet aircraft burns almost 6,000 pounds of kerosene and adds almost 19,000 pounds of carbon dioxide to the atmosphere. The environmental impact of air travel is so stark that Swedes even have a term for it: flygskam, or flight shame. But what if flying could be made zero carbon? “We have developed a solar technology that is able to produce liquid fuels using just two ingredients: solar energy and ambient air,” says Aldo Steinfeld, a renewable energy expert at the Swiss Federal Institute of Technology. “These hydrocarbon fuels release only as much carbon dioxide during combustion as was previously extracted from the air.” It may seem like alchemy, but the solar refinery Steinfeld has helped…

Matt Kaeberlein’s search for the secret to a long life began, in part, with 560 unique strains of baker’s yeast. He noticed that some of the strains with the greatest longevity tended to divide in slow motion. And he found that this slowdown, which takes place in the molecular mechanisms controlling cell division, could be tinkered with artificially by feeding the yeast a drug called rapamycin. As he began publishing his results in 2006, other researchers were finding that the drug — most commonly used to prevent rejection of organ transplants in humans — had a similar anti-aging effect in worms and flies. Several years later, a landmark paper in Nature showed that rapamycin could increase the lifespan of middle-aged mice by 9 to 14 percent. By then a professor…

As soon as I read Aram’s email, my heart sank. My former undergraduate student wanted to discuss an emergency operation on his mother’s brain? Yikes. Later that night, Aram and I spoke on the phone. He explained that less than a week earlier, his 56-year-old mother, Flora, was driving to work when her left hand went numb and dropped from the wheel. Nonetheless, she continued her rounds as a social worker, faithfully visiting clients. Flora sought help eight hours later, thus beginning a series of visits to the hospital. A second MRI the next day showed that Flora’s irregular mass had nearly doubled in size. At first, she passed her physical with flying colors. The next night, she felt icy currents flow through her arm and went back for a…

Maybe it’s a hazy snapshot of your first time riding a bicycle. Or the ability to recite the Pythagorean theorem. It could be as simple as that phone number you scrawled on a napkin before it landed in the trash. Whatever shape they take, our memories help define who we are — and what it means to be human. While scholars have been musing on memory since the time of Socrates, new tech has helped today’s scientists learn much more about the neural and biological machinery behind our recollections. These breakthroughs have led to the discovery that our memories reside in specific clusters of brain cells. Some scientists are exploring how people store and retrieve memories as they move through a virtual reality environment. Others are studying how emotions like…

“Historically, the large majority of [memory studies] have been done with rats and mice running through mazes,” says Suthana. “A lot of what we know about the brain comes from those studies. And, in order for us to translate those and see if they’re really true for humans, we need something to connect between the two.” In two studies currently under peer review, Suthana and her colleagues worked with patients with deep-brain implants for treating epileptic seizures. The researchers put virtual reality headsets on the patients, whose permanent implants enabled the scientists to record brain waves during the experiment. Once the participants donned goggles and motion-capture bodysuits studded with reflective dots to track their movements, they then performed a series of tests on learning, memory and navigation in a simulated…

For years, Melanie Musson’s friends have marveled at her superpower: staying healthy no matter what germs are making the rounds. Colds and flu felled plenty of Musson’s dormmates in college, but the viruses always seemed to pass her by. “I never got sick once,” she says. “I got about five hours of sleep a night, I finished school in three years, and I worked 30 hours a week throughout. My best friends labeled me ‘the machine.’” Musson’s ironclad immune system also set her apart at her first job. While she was working at an assisted living facility, her co-workers succumbed to a stomach virus that was running rampant. Undaunted, Musson offered to cover their shifts. “There I was, the brand-new employee, getting as much overtime as I wanted. I wasn’t…

Three major arteries circulate blood to different regions of the heart muscle — two on the left side of the heart, and one on the right. Blockages in the coronary arteries on the left or right side of the heart bring different consequences, explains Nicholas Ruthmann, cardiologist at the Cleveland Clinic in Ohio. The left side of the heart is the powerhouse, pumping blood with fresh nutrients and oxygen to the entire body. Blockages here turn deadly, fast (and are often called a “widowmaker”). The smaller right side of the heart takes in blood that’s completed its journey traveling around the body. A blockage here makes it difficult for the heart to pump blood into the lungs to receive oxygen, decreasing the amount of blood pumped out by the left…

Misinformation and outdated science abound when it comes to attaining our fittest selves. Gyms, social media and infomercials throw around buzzwords and promote fad routines, leaving many of us bewildered about what will actually boost our bodies — and what’s just smoke and mirrors. “It’s embarrassing,” says San Diego State University physiologist Fabio Comana, who sees “misconceptions, built on hearsay and YouTube videos,” on a daily basis. He adds: “There’s a lack of evidence-based science, and people are misinformed.” In the interest of science and helping you achieve a better you, we asked exercise science experts to set us straight on five of the top myths about the biomechanics of working out. 1 DO I NEED TO COOL DOWN? If you last set foot in a gym in the early…