An anonymous reader quotes a report from Motherboard: Scientists have discovered a bacteria with cells that measure a full centimeter in length, an astonishing size that makes it by far the largest bacterial species ever found and even “challenges our concept of a bacterial cell,” reports a new study. Bacteria are an extraordinarily diverse group of organisms that have inhabited Earth for billions of years and have evolved to occupy a dizzying variety of niches. Still, almost all of these microbes are composed of simple cells that measure about two microns in diameter, which is about 40 times smaller than a strand of human hair.

Thiomargarita magnifica, a bacteria discovered on sunken red mangrove leaves in Guadeloupe, Lesser Antilles, has blown this standard scale out of the water. The species has evolved filamentary cells that are “larger than all other known giant bacteria by ~50-fold,” making them “visible to the naked eye,” according to a study published on Thursday in Science.
Scientists led by Jean-Marie Volland, a marine biologist who holds joint appointments at the Laboratory for Research in Complex Systems and the Joint Genome Institute (JGI), a U.S. Department of Energy office at Lawrence Berkeley National Laboratory, suspect that this record-breaking adaptation is partly due to the astonishing number of duplicated genes wielded by T. magnifica, an ability that is known as polyploidy. […]

The results revealed that these bacteria contain DNA clusters in their cells, which are located in compartments bordered by membranes that the team called “pepins.” These organized pepins provide a stark contrast to the free-floating DNA seen in the cells of most bacteria. In addition, the team’s genetic sequencing revealed that T. magnifica contains hundreds of thousands of genome copies that are dispersed across the cell, adding up to about three times the number of genes in most bacteria, which is an extreme example of polyploidy. “These cellular features likely allow the organism to grow to an unusually large size and circumvent some of the biophysical and bioenergetic limitations on growth,” Volland and his colleagues said.

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A new breakthrough has allowed physicists to create a beam of atoms that behaves the same way as a laser, and that can theoretically stay on “forever.” ScienceAlert reports: At the root of the atom laser is a state of matter called a Bose-Einstein condensate, or BEC. A BEC is created by cooling a cloud of bosons to just a fraction above absolute zero. At such low temperatures, the atoms sink to their lowest possible energy state without stopping completely. When they reach these low energies, the particles’ quantum properties can no longer interfere with each other; they move close enough to each other to sort of overlap, resulting in a high-density cloud of atoms that behaves like one ‘super atom’ or matter wave. However, BECs are something of a paradox. They’re very fragile; even light can destroy a BEC. Given that the atoms in a BEC are cooled using optical lasers, this usually means that a BEC’s existence is fleeting.

Atom lasers that scientists have managed to achieve to date have been of the pulsed, rather than continuous variety; and involve firing off just one pulse before a new BEC needs to be generated. In order to create a continuous BEC, a team of researchers at the University of Amsterdam in the Netherlands realized something needed to change. “In previous experiments, the gradual cooling of atoms was all done in one place. In our setup, we decided to spread the cooling steps not over time, but in space: we make the atoms move while they progress through consecutive cooling steps,” explained physicist Florian Schreck. “In the end, ultracold atoms arrive at the heart of the experiment, where they can be used to form coherent matter waves in a BEC. But while these atoms are being used, new atoms are already on their way to replenish the BEC. In this way, we can keep the process going — essentially forever.” The research has been published in the journal Nature.

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Aiming to produce environmentally friendly alternatives to plastic food wrap and containers, a Rutgers scientist has developed a biodegradable, plant-based coating that can be sprayed on foods, guarding against pathogenic and spoilage microorganisms and transportation damage. From a report: Their article, published in the science journal Nature Food, describes the new kind of packaging technology using the polysaccharide/biopolymer-based fibers. Like the webs cast by the Marvel comic book character Spider-Man, the stringy material can be spun from a heating device that resembles a hair dryer and “shrink-wrapped” over foods of various shapes and sizes, such as an avocado or a sirloin steak. The resulting material that encases food products is sturdy enough to protect bruising and contains antimicrobial agents to fight spoilage and pathogenic microorganisms such as E. coli and listeria.

The research paper includes a description of the technology called focused rotary jet spinning, a process by which the biopolymer is produced, and quantitative assessments showing the coating extended the shelf life of avocados by 50 percent. The coating can be rinsed off with water and degrades in soil within three days, according to the study. […] The paper describes how the new fibers encapsulating the food are laced with naturally occurring antimicrobial ingredients — thyme oil, citric acid and nisin. Researchers in the Demokritou research team can program such smart materials to act as sensors, activating and destroying bacterial strains to ensure food will arrive untainted. This will address growing concern over food-borne illnesses as well as lower the incidence of food spoilage […].

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A retracted paper highlights chemistry’s history of trying to avoid the expensive, toxic — but necessary — catalyst. From a report: It’s hard to find a place on Earth untouched by palladium. The silvery-white metal is a key part of catalytic converters in the world’s 1.4 billion cars, which spew specks of palladium into the atmosphere. Mining and other sources add to this pollution. As a result, traces of palladium show up in some of the most remote spots on Earth, from Antarctica to the top of the Greenland ice sheet. Palladium is also practically indispensable for making drugs. That’s because catalysts with palladium atoms at their core have an unmatched ability to help stitch together carbon –carbon bonds. This kind of chemical reaction is key to building organic molecules, especially those used in medications.

“Every pharmaceutical we produce at some point or another has a palladium-catalysed step in it,” says Per-Ola Norrby, a pharmaceutical researcher at drug giant AstraZeneca in Gothenburg, Sweden. Palladium-catalysed reactions are so valuable that, in 2010, their discoverers shared a Nobel prize. But despite its versatility, chemists are trying to move away from palladium. The metal is more expensive than gold, and molecules that contain palladium can also be extremely toxic to humans and wildlife. Chemical manufacturers have to separate out all traces of palladium from their products and carefully dispose of the hazardous waste, which adds extra expense. Thomas Fuchb, a medicinal chemist at the life-sciences company Merck in Darmstadt, Germany, gives the example of a reaction to make 3 kilograms of a drug molecule for which the ingredients cost US$250,000. The palladium catalyst alone adds $100,000; purifying it out of the product another $30,000.

Finding less-toxic alternatives to the metal could help to reduce environmental harm from palladium waste and move the chemicals industry towards ‘greener’ reactions, says Tianning Diao, an organometallic chemist at New York University. Researchers hope to swap palladium for more common metals, such as iron and nickel, or invent metal-free catalysts that sidestep the issue altogether. Several times in the past two decades, researchers have reported finding palladium-free catalysts. But in what has become a recurring pattern for the field, each heralded discovery turned out to be a mistake.

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Keeping people out of rip currents is more about reading human behavior than reading warning signs. From a report: Worldwide, rips cause hundreds of drownings and necessitate tens of thousands of rescues every year. In Australia, where 85 percent of the population lives within an hour’s drive of the coast, rips cause more fatalities than floods, cyclones, and shark attacks combined. In 1938, one of the country’s most popular beaches, Sydney’s Bondi Beach, was the site of an infamous rip-current tragedy: within minutes, roughly 200 swimmers were swept away by a rip, leaving 35 people unconscious and five dead. More often, however, rips take one life at a time, garnering little media attention. For many casual beach visitors, the toll of rip currents goes unnoticed. […] Although almost three-quarters of beach users said they knew what a rip current is, only 54 percent could correctly define it. In addition, only half of the people she surveyed remembered seeing either the warning signs or the colored flags denoting surf conditions that were posted on or near the main access point to each beach. An even smaller percentage could recall what color the flags had been — green for calm, yellow for moderate, or red for dangerous conditions. “I was genuinely shocked,” Locknick says.

[…] Part of the challenge of preventing rip-related drownings stems from the lack of a simple method to escape them. Rip currents form when waves pile water near the shoreline. The water then gushes back out to sea, taking the path of least resistance. It might flow along channels carved in between sandbars or next to solid structures, such as jetties or rocky headlands. These types of rips can stick around year after year. Others are more erratic, creating fleeting bursts of seaward-flowing water on smooth, open beaches. People often mislabel rip currents as undertows or rip tides. Rip currents are not caused by tides, however, and undertows are a different, weaker current, formed when water pushed onto the beach moves back offshore along the seabed. Some telltale signs of a rip include a streak of churned-up, sandy water or a dark, flat gap between breaking waves.

It’s not surprising that rip currents are often misunderstood by the public because, for decades, beach-safety experts also had an oversimplified perception of their mechanics. In some of the earliest research on rips in the mid-20th century, American scientists watched sticks, pieces of kelp, and volleyballs float out to sea and described lanes of flowing water extending more than 300 meters offshore. This work formed the basis for the popular view of rip currents as jets flowing perpendicular to the beach, shooting out past the surf. To escape the river of current, experts recommended that bathers swim parallel to the beach — a message once broadcast through education campaigns and warning signs in the United States and Australia. As it turns out, that approach may not always work.

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Researchers have found that being outside drastically reduces the risk of developing short-sightedness. From a report: In the early 1980s Taiwan’s army realised it had a problem. More and more of its conscripts seemed to be short-sighted, meaning they needed glasses to focus on distant objects. “They were worried that if the worst happened [ie, an attack by China] their troops would be fighting at a disadvantage,” says Ian Morgan, who studies myopia at Australian National University, in Canberra. An island-wide study in 1983 confirmed that around 70% of Taiwanese school leavers needed glasses or contact lenses to see properly. These days, that number is above 80%. But happily for Taiwan’s generals, the military disparity has disappeared. Over the past few decades myopia rates have soared across East Asia (see chart 1 in the linked story). In the 1960s around 20-30% of Chinese school-leavers were short-sighted. These days they are just as myopic as their cousins across the straits, with rates in some parts of China running at over 80%.

Elsewhere on the continent things are even worse. One study of male high-school leavers in Seoul found 97% were short-sighted. Hong Kong and Singapore are not far behind. And although the problem is worst in East Asia, it is not unique to it. Reliable numbers for America and Europe are harder to come by. But one review article, published in 2015, claimed a European rate of between 20% and 40% — an order of magnitude higher than that which people working in the field think is the “natural,” background rate. For most of those affected, myopia is a lifelong, expensive nuisance. But severe myopia can lead to untreatable vision loss, says Annegret Dahlmann-Noor, a consultant ophthalmologist at Moorfields Eye Hospital, in London. A paper published in 2019 concluded that each one-dioptre worsening in myopia was associated with a 67% increase in prevalence of myopic maculopathy, an untreatable condition that causes blindness. (A dioptre is a measure of a lens’s focusing power.) In some parts of East Asia, 20% of young people have severe myopia, defined as -6 dioptres or worse (see chart 2 in linked story). “This is storing up a big problem for the coming decades,” says Kathryn Rose, head of orthoptics at the University of Technology, Sydney.

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The “use-by” and “best-by” dates printed on milk cartons and gallon jugs may soon become a thing of the past, giving way to more accurate and informative QR codes. Phys.Org reports: A new Cornell University study finds that consumers will use the QR codes to better depict how long the milk is drinkable and create substantially less agricultural and food waste. In the U.S., dairy products are among the top three food groups with the largest share of wasted food, said Samantha Lau, a doctoral student in food science who works in the lab of Martin Wiedmann, the professor of food safety in the College of Agriculture and Life Sciences.

In the early spring semester, Lau, also working with Cornell’s Milk Quality Improvement Program, connected with the Cornell Dairy Bar, which sells fluid milk in addition to ice cream on campus. She wanted to assess consumer acceptance for QR code technology that may one day replace the static best-by or sell-by dates commonly found on food products. Customers had a choice: purchasing milk with printed best-by dates, or buying containers with QR codes, which when scanned by a smart phone, would display the best-by date.

In the same Cornell Dairy Bar study, Lau placed a dynamic pricing element where consumers were encouraged to purchase milk with a shorter remaining shelf life — by offering a price discount as the best-by date approached. “During two-month study, over 60% of customers purchased the milk with the QR code, showing a considerable interest in using this new technology,” Lau said. “This revealed that the use of QR codes on food products can be an innovative way to address the larger issue of food waste.” Wiedmann says the technology also exists where smart milk cartons could communicate with smart refrigerators to inform a household of the need for fresh milk.

The study has been published in the Journal of Dairy Science.

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After 10 years of careful analysis and scrutiny, scientists of the CDF collaboration at the U.S. Department of Energy’s Fermi National Accelerator Laboratory announced today that they have achieved the most precise measurement to date of the mass of the W boson, one of nature’s force-carrying particles. Phys.Org reports: Using data collected by the Collider Detector at Fermilab, or CDF, scientists have now determined the particle’s mass with a precision of 0.01% — twice as precise as the previous best measurement. It corresponds to measuring the weight of an 800-pound gorilla to 1.5 ounces. The new precision measurement, published in the journal Science, allows scientists to test the standard model of particle physics, the theoretical framework that describes nature at its most fundamental level. The result: The new mass value shows tension with the value scientists obtain using experimental and theoretical inputs in the context of the standard model. If confirmed, this measurement suggests the potential need for improvements to the standard model calculation or extensions to the model.

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Researchers at the University of Nevada, Las Vegas were trying to understand how water might behave under the high pressures inside distant planets.
But along the way the team discovered a new form of ice, reports Phys.org, “redefining the properties of water at high pressures.”

Solid water, or ice, is like many other materials in that it can form different solid materials based on variable temperature and pressure conditions, like carbon forming diamond or graphite. However, water is exceptional in this aspect as there are at least 20 solid forms of ice known to us.

A team of scientists working in UNLV’s Nevada Extreme Conditions Lab pioneered a new method for measuring the properties of water under high pressure. The water sample was first squeezed between the tips of two opposite-facing diamonds — freezing into several jumbled ice crystals. The ice was then subjected to a laser-heating technique that temporarily melted it before it quickly re-formed into a powder-like collection of tiny crystals. By incrementally raising the pressure, and periodically blasting it with the laser beam, the team observed the water ice make the transition from a known cubic phase, Ice-VII, to the newly discovered intermediate, and tetragonal, phase, Ice-VIIt, before settling into another known phase, Ice-X….

While it’s unlikely we’ll find this new phase of ice anywhere on the surface of Earth, it is likely a common ingredient within the mantle of Earth as well as in large moons and water-rich planets outside of our solar system. The team’s findings were reported in the March 17 issue of the journal Physical Review B…. The work also recalibrates our understanding of the composition of exoplanets, UNLV physicist Ashkan Salamat added. Researchers hypothesize that the Ice-VIIt phase of ice could exist in abundance in the crust and upper mantle of expected water-rich planets outside of our solar system, meaning they could have conditions habitable for life.

Thanks to long-time Slashdot reader fahrbot-bot for sharing the story…

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“Exposure to even moderate ambient lighting during nighttime sleep, compared to sleeping in a dimly lit room, harms your cardiovascular function during sleep and increases your insulin resistance the following morning,” announced Northwestern Medicine, citing a new study recently published in the Proceedings of the National Academy of Sciences.

The Washington Post reports:
Researchers at Northwestern University had two groups of 10 young adults sleep in differently lit rooms. One group slept in rooms with dim light for two nights; the other slept one night in a room with dim night and the next in a room with moderate overhead light — about the equivalent of an overcast day. Participants wore heart monitors at night. In the morning, they did a variety of glucose tests.

Both groups got the same amount of sleep but their bodies experienced very different nights. Both groups responded well to insulin the first night, when they both slept in dim lighting. On the second night, however, the group sleeping in brighter lighting didn’t respond as well to insulin. The dim light sleepers’ insulin resistance scores fell about 4 percent on the second night, while the bright sleepers’ rose about 15 percent. Their heart rates were faster on the bright night, too.

“[J]ust a single night of exposure to moderate room lighting during sleep can impair glucose and cardiovascular regulation, which are risk factors for heart disease, diabetes and metabolic syndrome,” concludes senior study author Dr. Phyllis Zee. “It’s important for people to avoid or minimize the amount of light exposure during sleep.”
From Northwestern’s announcement:
There is already evidence that light exposure during daytime increases heart rate via activation of the sympathetic nervous system, which kicks your heart into high gear and heightens alertness to meet the challenges of the day. “Our results indicate that a similar effect is also present when exposure to light occurs during nighttime sleep,” Zee said….

An earlier study published in JAMA Internal Medicine looked at a large population of healthy people who had exposure to light during sleep. They were more overweight and obese, Zee said. “Now we are showing a mechanism that might be fundamental to explain why this happens. We show it’s affecting your ability to regulate glucose,” Zee said.

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