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Russia Unveils Model of Proposed Space Station After Leaving ISS

Mar, 16/08/2022 - 02:00
The Russian space agency has unveiled a physical model of what a planned Russian-built space station will look like, suggesting Moscow is serious about abandoning the International Space Station (ISS) and going it alone. The Guardian reports: Russia wants to reduce its dependency on western countries and forge ahead on its own, or cooperate with countries such as China and Iran, after sanctions were imposed by the west as a result of the invasion of Ukraine. Roscosmos presented a model of the space station, nicknamed "Ross" by Russian state media, on Monday at a military-industrial exhibition outside Moscow. Roscosmos said its space station would be launched in two phases, without giving dates. For the first phase a four-module space station would start operating. That would be followed by two more modules and a service platform, it said. That would be enough, when completed, to accommodate up to four cosmonauts and scientific equipment. Roscosmos has said the station would afford Russian cosmonauts a much wider view by which to monitor Earth than their current segment. Although designs for some of the station exist, design work is still under way on other segments. Russian state media have suggested the launch of the first stage is planned for 2025-26 and no later than 2030. Launch of the second and final stage is planned for 2030-35, they have reported. The space station, as currently conceived, would not have a permanent human presence but would be staffed twice a year for extended periods. Dmitry Rogozin, the previous head of Roscosmos and a hardliner known for his tough statements against the west, has suggested the new space station could fulfil a military purpose if necessary.

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An Eye Implant Engineered From Proteins In Pigskin Restored Sight In 14 Blind People

Lun, 15/08/2022 - 20:25
According to a new study published in the journal Nature Biotechnology, researchers implanted corneas made from pig collagen to restore sight in 20 people who were blind or visually impaired. "Fourteen of the patients were blind before they received the implant, but two years after the procedure, they had regained some or all of their vision," notes NBC News. "Three had perfect vision after the surgery." From the report: The patients, in Iran and India, all suffered from keratoconus, a condition in which the protective outer layer of the eye progressively thins and bulges outward. "We were surprised with the degree of vision improvement," said Neil Lagali, a professor of experimental ophthalmology at Linkoping University in Sweden who co-authored the study. Not all patients experienced the same degree of improvement, however. The 12 Iranian patients wound up with an average visual acuity of 20/58 with glasses; functional vision is defined as 20/40 or better with lenses. Nonetheless, Dr. Marian Macsai, a clinical professor of ophthalmology at the University of Chicago who wasn't involved in the study, said the technology could be a game changer for those with keratoconus, which affects roughly 50 to 200 out of every 100,000 people. It might also have applications for other forms of corneal disease. To create the implant, Lagali and his team dissolved pig tissue to form a purified collagen solution. That was used to engineer a hydrogel that mimics the human cornea. Surgeons then made an incision in a patient's cornea for the hydrogel. "We insert our material into this pocket to thicken the cornea and to reshape it so that it can restore the cornea's function," Lagali said. Traditionally, human tissue is required for cornea transplants. But it's in short supply, because people must volunteer to donate it after they die. So, Lagali said, his team was looking for a low-cost, widely available substitute. "Collagen from pigskin is a byproduct from the food industry," he said. "This makes it broadly available and easier to procure." After two years, the patients' bodies hadn't rejected the implants, and they didn't have any inflammation or scarring. But any experimental medical procedure comes with risk. In this case, Soiberman said, a foreign molecule like collagen could induce an immune reaction. The researchers prescribed patients an eight-week course of immunosuppressive eyedrops to lower the risk, which is less than the amount given to people who receive cornea transplants from human tissue. In those cases, patients take immunosuppressive medicine for more than a year, Lagali said. "There's always a risk for rejection of the human donor tissue because it contains foreign cells," he said. "Our implant does not contain any cells ... so there's a minimal risk of rejection." The procedure itself was also quicker than traditional cornea transplants. The researchers said each operation took about 30 minutes, whereas transplants of human tissue can take a couple of hours. [...] It's not yet clear whether the surgery would work for patients who have other forms of corneal disease aside from keratoconus.

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The US Could See a New 'Extreme Heat Belt' By 2053

Lun, 15/08/2022 - 14:20
An "extreme heat belt" reaching as far north as Chicago is taking shape, a corridor that cuts through the middle of the country and would affect more than 107 million people over the next 30 years, according to new data on the country's heat risks. From a report: The report, released Monday by the nonprofit research group First Street Foundation, found that within a column of America's heartland stretching from Texas and Louisiana north to the Great Lakes, residents could experience heat index temperatures above 125 degrees Fahrenheit by 2053 -- conditions that are more commonly found in California's Death Valley or in parts of the Middle East. The projections are part of First Street Foundation's new, peer-reviewed extreme heat model, which shows that most of the country will have upticks in the number of days with heat index temperatures above 100 degrees over the next 30 years as a result of climate change. The heat index represents what a temperature feels like to the human body when humidity and air temperature are combined. It is commonly referred to as the "feels like" temperature. "Everybody is affected by increasing heat, whether it be absolute increases in dangerous days or it's just a local hot day," said First Street Foundation's chief research officer, Jeremy Porter, a professor and the director of quantitative methods in social sciences at the City University of New York.

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Science is Getting Closer To a World Without Animal Testing

Lun, 15/08/2022 - 13:40
Academics and pharmaceutical companies hope that technology based on human cells will help them phase mice and monkeys out of their labs. From a report: The umbrella term for the new field is microphysiological systems or MPS, which includes tumoroids, organoids and organs-on-a-chip. Organoids are grown from stem cells to create 3D tissue in a dish resembling miniature human organs; heart organoids beat like the real thing, for example. Organs-on-a-chip are plastic blocks lined with stem cells and a circuit that stimulates the mechanics of an organ. "We need to move away from animals in a systematic way," says Salim Abdool Karim, South Africa's leading infectious disease expert. "Thatâ...âinvolves regulators being given the data to show that non-animal biological systems will give us compatible, if not better, information." Nathalie Brandenburg co-founded Swiss start-up Sun Bioscience in 2016 to create standard versions of organoids, which makes it easier to trust that results are comparable, and convince scientists and regulators to use them. "When we started we had to tell people what organoids were," she says, referring to the early stage of her research journey. In the past two years, and particularly as scientists emerged from lockdowns -- when many had time to read up on the technology -- demand from large pharmaceutical companies for Sun's products has soared, she says. Companies are becoming more interested in reducing their reliance on animals for ethical reasons, says Arron Tolley, chief executive of Aptamer Group, which creates artificial antibodies for use in diagnostics and drugs. "People are becoming more responsible now, from a corporate governance point of view, and looking to remove animal testing when necessary," he says. Using larger animals, such as monkeys, is particularly problematic, Tolley adds. "The bigger and cuter they get, the more people are aware of the impact." Rare diseases are especially fertile ground for models based on human tissues, says James Hickman, chief scientist at Hesperos, an organ-on-a-chip company based in Florida. "There are 7,000 rare diseases and only 400 are being actively researched because there are no animal models," Hickman says. "We're not just talking about replacing animals or reducing animals, these systems fill a void where animal models don't exist."

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A Desert Nation Turns To Hydroponics To Make Feed for Its Livestock

Lun, 15/08/2022 - 10:22
The United Arab Emirates is turning to vertical farming and hydroponics to produce food for local livestock as the desert nation tries to reduce its reliance on imports and shield itself from disruptions to global supply chains. From a report: Abu Dhabi-based startup World of Farming will begin building on-site operations at local farms later this year to provide fodder for meat and dairy producers that currently rely on imports for as much as 80% to 90% of their animal feed, said Faris Mesmar, chief executive officer of Hatch & Boost Ventures, a venture capital firm that launches and scales its own startups. "This region doesn't have a lot of arable land and the dependency on imports is becoming an issue for all local privately held and commercial farms," said Mesmar in an interview. Local livestock producers "find themselves with no consistent access with food to feed their animals." Land or resource-scarce countries from the Middle East to Asia are increasingly seeking to insulate themselves against food shocks and global supply chain disruptions caused by the pandemic, politics and extreme weather. Russia's invasion of Ukraine has disrupted supplies from one of the world's top grain exporters, while heat waves have been wilting crops in Europe and the US. Techniques such as hydroponics, drip irrigation and enclosed cultivation allow desert nations such as the UAE to reduce costly imports of high-value fresh produce. Dubai-based airline Emirates opened what it says is the world's largest hydroponics farm in July to supply leafy greens for in-flight meals. Hydroponic, vertical farms typically grow plants indoors without soil, irrigating the crops with a water-based nutrient solution and often use artificial light.

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Researchers: It's 'Unlikely' There's Water- or Ice-Saturated Layers Below InSight Mars Lander

Dom, 14/08/2022 - 20:48
Did Mars ever support life? One clue might be quantifying just how much ice (and other minerals) are lurking just below the planet's surface, a team of researchers argued this month. "If life exists on Mars, that is where it would be," they said in a news release this week. "There is no liquid water on the surface," but in a contrary scenario, "subsurface life would be protected from radiation." Locating ice and minerals has another benefit too, they write in the journal Geophysical Research Letters: to "prepare for human exploration." And fortunately, there's a tool on the InSight lander (which touched down in 2018) that can help estimate the velocity of seismic waves inside the geological crust of Mars — velocities which change depending on which rock types are present, and which materials are filling pores within rocks (which could be ice, water, gas, or other mineral cements). That's the good news. But after running computer models of applied rock physics thousands and thousands of times, the researchers believe it's unlikely that there's any layers saturated with water (or ice) in the top 300 meters (1,000 feet) of the crust of Mars. "Model results confirm that the upper 300 meters of Mars beneath InSight is most likely composed of sediments and fractured basalts." The researchers reached a discouraging conclusion, reports Space.com "The chances of finding Martian life appear poor at in the vicinity of NASA's InSight lander." The subsurface around the landing zone — an equatorial site chosen especially for its flat terrain and good marsquake potential — appears loose and porous, with few ice grains in between gaps in the crust, researchers said.... The equatorial region where InSight is working, in theory, should be able to host subsurface water, as conditions are cold enough even there for water to freeze. But the new finding is challenging scientists' assumptions about possible ice or liquid water beneath the subsurface near InSight, whose job is to probe beneath the surface. While images from the surface have suggested there might be sedimentary rock and lava flows beneath InSight, researchers' models have uncertainties about porosity and mineral content. InSight is helping to fill in some of those gaps, and its new data suggests that "uncemented material" largely fills in the region blow the lander. That suggests little water is present, although more data needs to be collected. It's unclear how representative the InSight data is of the Martian subsurface in general, but more information may come courtesy of future missions. NASA is considering a Mars Life Explorer that would drill 6 feet (2 meters) below the surface to search for possible habitable conditions. Additionally, a proposed Mars Ice Mapper Mission could search for possible water reservoirs for human missions. And of course, as the researchers point out in their announcement, "big ice sheets and frozen ground ice remain at the Martian poles."

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Nuclear Fusion Breakthrough Confirmed: California Team Achieved Ignition. Research Continues

Sáb, 13/08/2022 - 20:34
"A major breakthrough in nuclear fusion has been confirmed a year after it was achieved at a laboratory in California," reports Newsweek: Researchers at Lawrence Livermore National Laboratory's National Ignition Facility (NIF) recorded the first case of ignition on August 8, 2021, the results of which have now been published in three peer-reviewed papers.... Ignition during a fusion reaction essentially means that the reaction itself produced enough energy to be self-sustaining, which would be necessary in the use of fusion to generate electricity. If we could harness this reaction to generate electricity, it would be one of the most efficient and least polluting sources of energy possible. No fossil fuels would be required as the only fuel would be hydrogen, and the only by-product would be helium, which we use in industry and are actually in short supply of.... This landmark result comes after years of research and thousands of man hours dedicated to improving and perfecting the process: over 1,000 authors are included in the Physical Review Letters paper. This week the laboratory said that breakthrough now puts researchers "at the threshold of fusion gain and achieving scientific ignition," with the program's chief scientist calling it "a major scientific advance in fusion research, which establishes that fusion ignition in the lab is possible at the National Ignition Facility." More news from this week's announcement by the Lawrence Livermore National Laboratory: Since the experiment last August, the team has been executing a series of experiments to attempt to repeat the performance and to understand the experimental sensitivities in this new regime. "Many variables can impact each experiment," Kritcher said. "The 192 laser beams do not perform exactly the same from shot to shot, the quality of targets varies and the ice layer grows at differing roughness on each target...." While the repeat attempts have not reached the same level of fusion yield as the August 2021 experiment, all of them demonstrated capsule gain greater than unity with yields in the 430-700 kJ range, significantly higher than the previous highest yield of 170 kJ from February 2021. The data gained from these and other experiments are providing crucial clues as to what went right and what changes are needed in order to repeat that experiment and exceed its performance in the future. The team also is utilizing the experimental data to further understanding of the fundamental processes of fusion ignition and burn and to enhance simulation tools in support of stockpile stewardship. Looking ahead, the team is working to leverage the accumulated experimental data and simulations to move toward a more robust regime — further beyond the ignition cliff — where general trends found in this new experimental regime can be better separated from variability in targets and laser performance. Efforts to increase fusion performance and robustness are underway via improvements to the laser, improvements to the targets and modifications to the design that further improve energy delivery to the hotspot while maintaining or even increasing the hot-spot pressure. This includes improving the compression of the fusion fuel, increasing the amount of fuel and other avenues. "It is extremely exciting to have an 'existence proof' of ignition in the lab," said Omar Hurricane, chief scientist for the lab's inertial confinement fusion program. "We're operating in a regime that no researchers have accessed since the end of nuclear testing, and it's an incredible opportunity to expand our knowledge as we continue to make progress." Thanks to long-time Slashdot reader hesdeadjim99 for sharing the news.

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Are Space Scientists Ready For Starship - the Biggest Rocket Ever?

Sáb, 13/08/2022 - 18:10
Slashdot reader sciencehabit shared this thought-provoking anecdote from Science magazine: NASA's Lunar Crater Observation and Sensing Satellite mission was brutish and short. It began on 9 October 2009, when the hull of a spent Centaur rocket stage smashed into Cabeus crater, near the south pole of the Moon, with the force of about 2 tons of TNT. And it ended minutes later, when a trailing spacecraft flew through and analyzed the lofted plume of debris before it, too, crashed. About 6% of the plume was water, presumably from ice trapped in the shadowed depths of the crater, where the temperature never rises above -173ÂC. The Moon, it turned out, wasn't as bone dry as the Apollo astronauts believed. "That was our first ground truth that there is water ice," says Jennifer Heldmann, a planetary scientist at NASA's Ames Research Center who worked on the mission. Today, Heldmann wants to send another rocket to probe lunar ice — but not on a one-way trip. She has her eye on Starship, a behemoth under development by private rocket company SpaceX that would be the largest flying object the world has ever seen. With Starship, Heldmann could send 100 tons to the Moon, more than twice the lunar payload of the Saturn V, the workhorse of the Apollo missions. She dreams of delivering robotic excavators and drills and retrieving ice in freezers onboard Starship, which could return to Earth with tens of tons of cargo. By analyzing characteristics such as the ice's isotopic composition and its depth, she could learn about its origin: how much of it came from a bombardment of comets and asteroids billions of years ago versus slow, steady implantation by the solar wind. She could also find out where the ice is abundant and pure enough to support human outposts. "It's high-priority science, and it's also critical for exploration," Heldmann says. When SpaceX CEO Elon Musk talks up Starship, it's mostly about human exploration: Set up bases on Mars and make humans a multiplanetary species! Save civilization from extinction! But Heldmann and many others believe the heavy lifter could also radically change the way space scientists work. They could fly bigger and heavier instruments more often — and much more cheaply, if SpaceX's projections of cargo launch costs as low as $10 per kilogram are to be believed. On Mars, they could deploy rovers not as one-offs, but in herds. Space telescopes could grow, and fleets of satellites in low-Earth orbit could become commonplace. Astronomy, planetary science, and Earth observation could all boldly go, better than they ever have before. Of course, Starship isn't real yet. All eyes will be on a first orbital launch test, expected sometime in the coming months. Starship would've made it easier to deploy the massive James Webb Space Telescope, the article points out, while in the future Starship's extra fuel capacity could make it easier to explore Mercury, earth's outermost planets, and even interstellar space. In fact, Heldmann and colleagues have now suggested that NASA create a dedicated funding line for missions relying on Starship. Heldmann argues that "We on the science side need to be ready to take advantage of those capabilities when they come online." The article notes that at an event in February, Elon Musk "explained how a single Starship, launching three times per week, would loft more than 15,000 tons to orbit in a year — about as much as all the cargo that has been lifted in the entire history of spaceflight."

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Ransomware Causes 'Major', Long-Lasting Outage for UK Health Service's Patient Notes

Sáb, 13/08/2022 - 16:54
The Independent reports that the UK's National Health System is experiencing a major outage "expected to last for more than three weeks" after a third-party supplying the NHS's "CareNotes" software was hit by ransomware. Unfortunately, this leaves doctors unable to see their notes on patients, and the mental health trusts that provide care "across the country will be left unable to access patient notes for weeks, and possibly months." Oxford Health NHS Foundation Trust has declared a critical incident over the outage, which is believed to affect dozens of trusts, and has told staff it is putting emergency plans in place. One NHS trust chief said the situation could possibly last for "months" with several mental health trusts, and there was concern among leaders that the problem is not being prioritised. In an email to staff, Oxford Health NHS Foundation Trust chief executive Nick Broughton, said: "The cyberattack targeted systems used to refer patients for care, including ambulances being dispatched, out of hours appointment bookings, triage, out of hours care, emergency prescriptions and safety alerts. It also targeted the finance system used by the trust.... An NHS director said: "The whole thing is down. It's really alarming...we're carrying a lot of risk as a result of it because you can't get records and details of assessments, prescribing, key observations, medical mental health act observations. You can't see any of it...Staff are going to have to write everything down and input it later." They added: "There is increased risk to patients. We're finding it hard to discharge people, for example to housing providers, because we can't access records." "'Weeks' is an unreasonable period," argues Slashdot reader Bruce66423, wondering why it couldn't be resolved with a seemingly simple restore from backups? And Alan Woodward, a professor of cybersecurity at Surrey University, warns the Guardian that "Even if it was ransomware ... that doesn't mean data was not stolen."

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Researchers Pinpointed Covid-19's Origin to Within a Few Metres

Sáb, 13/08/2022 - 15:40
Australia's public broadcaster interviewed a virologist who "played a key role in mapping the evolution of COVID-19" (and was also "the first person to release the sequence of SARS-CoV-2 to the world.") But interestingly, this Australian virologist also visited the Wuhan market in 2014, "and recognised the risk of virus transmission between animals and humans and suggested taking some samples." "While I was there, I noticed there were these live wildlife for sale, particularly raccoon dogs and ... muskrats" he said. "I took the photographs because I thought to myself: 'God, that's, that's not quite right'." Raccoon dogs had been associated with the emergence of a different coronavirus outbreak, SARS-CoV-1, in 2002-04, which became known worldwide as the SARS virus. Even in 2014, Professor Holmes believed the market could become a site of virus transmission between animals and humans. The monitoring that Professor Holmes suggested never took place but, in the early days of COVID-19, he was still convinced that a market like the one in Wuhan was the logical origin of the virus. "They are the kind of engine room of [this sort] of disease emergence ... because what you're doing is you're putting humans and wildlife in close proximity to each other," he said. The professor also describes the theory that the virus some how leaked from a Chinese lab as "horrendous, blame-game finger-pointing," noting that the nearest lab is miles away. And he cites other reasons the market is where the virus originated: Aside from the geographic clustering, he also points to the fact that two different strands emerged almost simultaneously in humans, something that is much more likely if the virus had already been mutating in animals. "They're sufficiently far apart that they were probably independent jumps. "It means there was a pool of infected animals in the market and it's mutated amongst them before it jumped to humans." All of this has led Professor Holmes to conclude that the question of how COVID-19 emerged is settled. "I'm extremely confident that the virus is not from a laboratory. I think that's just a nonsensical theory," he said. Detailed mapping of where samples were detected inside the Huanan seafood wholesale market allowed Professor Holmes and his colleagues to even pinpoint to a few square metres where COVID-19 was likely to have jumped between humans and animals. "It's extraordinary," he said. "And I took a photo in 2014 of one of the stalls that was the most positively tested in the whole market."

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Polio Has Been Detected In New York City Wastewater, Officials Say

Vie, 12/08/2022 - 22:30
An anonymous reader quotes a report from The New York Times: Polio has been detected in New York City wastewater, suggesting that the virus that causes the disease is probably circulating in the city, the health authorities said on Friday. The announcement came three weeks after a man in Rockland County, N.Y., north of the city, was diagnosed with polio thatleft him with paralysis. Health officials fear that the detection of polio in New York City's wastewater could precede other cases of paralytic polio. The spread of the virus poses a risk to unvaccinated people, but a three-dose course of the vaccine provides at least 99 percent protection. Most adults in the United Stateswere vaccinated against polio as children. In New York City, the overall rate of polio vaccination among children 5 and under is 86 percent. Still, insome city ZIP codes, fewer thantwo-thirds of children in that group have received a full regimen, a figure that worries health officials. (The citywide vaccination rate dipped amid the pandemic, as visits to pediatricians were postponed.) Although many people who become infected with polio do not develop symptoms, about 4 percent will get viral meningitis and about 1 in 200 will become paralyzed, according to the health authorities. Parents of children who have not yet been fully vaccinated should see that they are immediately, officials said. "While the polio virus had previously been detected in wastewater samples in Rockland and neighboring Orange Counties, the announcement on Friday was the first sign it had been found in New York City," adds the report. "The city's health department did not provide details about where exactly in the five boroughs polio had been found in the wastewater, nor did officials provide dates for when the virus was detected or say how many samples had tested positive." Further reading: Vaccine-Derived Polio Is On the Rise

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How Thinking Hard Makes the Brain Tired

Vie, 12/08/2022 - 13:01
An anonymous reader shares a report: Physical labour is exhausting. A long run or a hard day's sweat depletes the body's energy stores, resulting in a sense of fatigue. Mental labour can also be exhausting. Even resisting that last glistening chocolate-chip cookie after a long day at a consuming desk job is difficult. Cognitive control, the umbrella term encompassing mental exertion, self-control and willpower, also fades with effort. But unlike the mechanism of physical fatigue, the cause of cognitive fatigue has been poorly understood. Previous accounts were incomplete. One of the most widely known, the biological one, draws from what is known about muscular fatigue. It posits that exerting cognitive control uses up energy in the form of glucose. At the end of a day spent intensely cogitating, the brain is metaphorically running on fumes. The problem with this version of events is that the energy cost associated with thinking is minimal. One analysis of previous studies suggests that cognitively overworked and "depleted" brains use less than one-tenth of a Tic-Tac's worth of additional glucose. If cognitive fatigue is not caused by a lack of energy, then what explains it? A team of scientists led by Antonius Wiehler of Pitie-Salpetriere University Hospital, in Paris, looked at things from what is termed a neurometabolic point of view. They hypothesise that cognitive fatigue results from an accumulation of a certain chemical in the region of the brain underpinning control. That substance, glutamate, is an excitatory neurotransmitter that abounds in the central nervous systems of mammals and plays a role in a multitude of activities, such as learning, memory and the sleep-wake cycle. In other words, cognitive work results in chemical changes in the brain, which present behaviourally as fatigue. This, therefore, is a signal to stop working in order to restore balance to the brain. In their new paper in Current Biology, the researchers describe an experiment they undertook to explain how all this happens.

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New Research Reveals the Circadian Clock Influences Cell Growth, Metabolism, and Tumor Progression

Vie, 12/08/2022 - 08:00
An anonymous reader quotes a report from Phys.Org: In a new University of California, Irvine-led study, researchers define how the circadian clock influences cell growth, metabolism and tumor progression. Their research also reveals how disruption of the circadian clock impacts genome stability and mutations that can further drive critical tumor-promoting pathways in the intestine. In this study, researchers found that both genetic disruption and environmental disruption of the circadian clock contribute to the mutation of the adenomatous polyposis coli (APC) tumor suppressor, which is found in the vast majority of human colorectal cancers (CRC). APC point mutations, deletions, and loss of heterozygosity (LOH) events have been reported in approximately 80 percent of human CRC cases, and it is these mutations that drive the initiation of intestinal adenoma development. "As a society, we are exposed to several environmental factors that influence our biological clock, including night shift work, extended light exposure, changes in sleep/wake cycles and altered feeding behavior," said Selma Masri, Ph.D., assistant professor of biological chemistry at UCI School of Medicine. "Strikingly, we have seen an alarming increase in several young-onset cancers, including colorectal cancer. The underlying cause of this increased incidence of cancer in adults in their 20s and 30s remains undefined. However, based on our findings, we now believe that disruption of the circadian clock plays an important role." The study has been published in the journal Science Advances.

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DOE Digs Up Molten Salt Nuclear Reactor Tech, Los Alamos To Lead the Way Back

Vie, 12/08/2022 - 02:00
After more than 50 years, molten salt nuclear reactors might be making a comeback. The US Department of Energy (DoE) has tapped Los Alamos National Laboratory (LANL) to lead a $9.25 million study into the structural properties and materials necessary to build them at scale. The Register reports: "The US needs projects like this one to advance nuclear technologies and help us achieve the Biden-Harris administration's goals of clean energy by 2035 and a net-zero economy by 2050," said Asmeret Asefaw Berhe, director of the office of science, in a statement. The study, conducted as part of the Scientific Discovery though Advanced Computing (SciDAC) program, seeks to gain a better understanding of the relationship between corrosion and irradiation effects at the atomic scale in metals exposed to molten salt reactors through simulation. This isn't the first time the DoE has explored this reactor tech. In the middle of last century, Oak Ridge National Laboratory (ORNL) took the lessons learned from the Aircraft Reactor experiment to build a functional nuclear aircraft power source and began construction of a molten salt test reactor. The experiments, conducted between 1957 and 1969, utilized a mixture of lithium, beryllium, zirconium, and uranium fluoride salts. Cooling was also achieved using a fluoride salt mixture, but it lacked the uranium and zirconium found in the fuel. The experiments proved promising, as molten salt reactors were generally smaller and considered safer compared to the pressurized water reactors still used today. But both proved too heavy for powered flight or materials design. Because cooling was achieved by circulating molten salt through a heat exchanger as opposed to water, the risk of a steam explosion is effectively nonexistent. However, as the Oak Ridge National Laboratory found during the Molten Salt Reactor Experiment, fluoride salts are incredibly corrosive and required hardened materials to safely contain them. "ORNL's Molten Salt Reactor Experiment utilized specialized materials fabricated from Hastelloy-N -- a nickel-molybdenum alloy developed by the lab with a high resistance to corrosion even at high temperatures," adds the reports. "The research program announced this week will revisit the material choices and examine a variety of metals using higher-performance compute resources to simulate how they'll perform at scale in these reactors."

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A New Study Overturns 100-Year-Old Understanding of Color Perception

Jue, 11/08/2022 - 22:30
An anonymous reader quotes a report from Phys.Org: A new study corrects an important error in the 3D mathematical space developed by the Nobel Prize-winning physicist Erwin Schrodinger and others, and used by scientists and industry for more than 100 years to describe how your eye distinguishes one color from another. The research has the potential to boost scientific data visualizations, improve TVs and recalibrate the textile and paint industries. [...] "Our original idea was to develop algorithms to automatically improve color maps for data visualization, to make them easier to understand and interpret," [said Roxana Bujack, a computer scientist with a background in mathematics who creates scientific visualizations at Los Alamos National Laboratory and lead author of the paper]. So the team was surprised when they discovered they were the first to determine that the longstanding application of Riemannian geometry, which allows generalizing straight lines to curved surfaces, didn't work. To create industry standards, a precise mathematical model of perceived color space is needed. First attempts used Euclidean spaces -- the familiar geometry taught in many high schools; more advanced models used Riemannian geometry. The models plot red, green and blue in the 3D space. Those are the colors registered most strongly by light-detecting cones on our retinas, and -- not surprisingly -- the colors that blend to create all the images on your RGB computer screen. In the study, which blends psychology, biology and mathematics, Bujack and her colleagues discovered that using Riemannian geometry overestimates the perception of large color differences. That's because people perceive a big difference in color to be less than the sum you would get if you added up small differences in color that lie between two widely separated shades. Riemannian geometry cannot account for this effect. "We didn't expect this, and we don't know the exact geometry of this new color space yet," Bujack said. "We might be able to think of it normally but with an added dampening or weighing function that pulls long distances in, making them shorter. But we can't prove it yet." The findings appear in the journal Proceedings of the National Academy of Science.

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China Overtakes the US In Scientific Research Output

Jue, 11/08/2022 - 17:02
An anonymous reader quotes a report from The Guardian: China has overtaken the US as the world leader in both scientific research output and "high impact" studies, according to a report published by Japan's science and technology ministry. The report, which was published by Japan's National Institute of Science and Technology Policy (NISTP) on Tuesday, found that China now publishes the highest number of scientific research papers yearly, followed by the US and Germany. The figures were based on yearly averages between 2018 and 2020, and drawn from data compiled by the analytics firm Clarivate. The Japanese NISTP report also found that Chinese research comprised 27.2% of the world's top 1% most frequently cited papers. The number of citations a research paper receives is a commonly used metric in academia. The more times a study is cited in subsequent papers by other researchers, the greater its "citation impact." The US accounted for 24.9% of the top 1% most highly cited research studies, while UK research was third at 5.5%. China published a yearly average of 407,181 scientific papers, pulling ahead of the US's 293,434 journal articles and accounting for 23.4% of the world's research output, the report found. China accounted for a high proportion of research into materials science, chemistry, engineering and mathematics, while US researchers were more prolific in research into clinical medicine, basic life sciences and physics. "China is one of the top countries in the world in terms of both the quantity and quality of scientific papers," Shinichi Kuroki of the Japan Science and Technology Agency told Nikkei Asia. "In order to become the true global leader, it will need to continue producing internationally recognized research."

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CDC Drops Quarantine, Distancing Recommendations For COVID-19

Jue, 11/08/2022 - 16:42
The nation's top public health agency relaxed its COVID-19 guidelines Thursday, dropping the recommendation that Americans quarantine themselves if they come into close contact with an infected person. The Centers for Disease Control and Prevention also said people no longer need to stay at least 6 feet away from others. The Associated Press reports: The changes, which come more than 2 1/2 years after the start of the pandemic, are driven by a recognition that an estimated 95% of Americans 16 and older have acquired some level of immunity, either from being vaccinated or infected, agency officials said. "The current conditions of this pandemic are very different from those of the last two years," said the CDC's Greta Massetti, an author of the guidelines. Perhaps the biggest education-related change is the end of the recommendation that schools do routine daily testing, although that practice can be reinstated in certain situations during a surge in infections, officials said. The CDC also dropped a "test-to-stay" recommendation, which said students exposed to COVID-19 could regularly test -- instead of quarantining at home -- to keep attending school. With no quarantine recommendation anymore, the testing option disappeared too. Masks continue to be recommended only in areas where community transmission is deemed high, or if a person is considered at high risk of severe illness.

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Some Firefly Species Await a Night That Never Comes

Jue, 11/08/2022 - 16:25
A study found that while some fireflies shrugged off light pollution, members of other species failed to mate even when males and females could find each other. From a report: As dusk deepens the shadow at the forest's edge, a tiny beacon lights up the gloom. Soon, the twilight is full of drifting lights, each winking a message in peculiar semaphore: "Male seeks female for brief union." This courtship plays out on summer nights the world over among beetles of the Lampyridae family, commonly known as fireflies. The darkness in which fireflies have always pursued their liaisons, however, has been breached by the glare of artificial lights. Humans' love affair with illumination has led to much of the Earth's habitable surfaces suffering light pollution at night. In recent years, scientists who study fireflies have heard from people who are worried that the insects may be in decline, said Avalon Owens, an entomologist at Tufts University. "There's this sense of doom. They seem to not be in places where they used to be," she said. So little is known about how fireflies live that it is hard to assess whether they are in danger -- and if so, why, said Dr. Owens. But in a study published Wednesday in the journal Royal Society Open Science, she and Sara Lewis, a professor of biology at Tufts University, shone some light on how fireflies respond to artificial illumination. Experiments in forests and fields as well as the lab showed that while some North American fireflies would mate with wild abandon, regardless of illumination, others did not complete a single successful mating under the glare of the lights. Fireflies seem to rely primarily on flashes of light to find each other, which means light pollution could threaten their ability to see mates. In the four common species the study examines, the females hide on the ground and observe as males wander the skies. When a female responds to a male's flashing with her own, the two enter into a dialogue that can end in a meeting, and eventually mating.

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The Search For an AC That Doesn't Destroy the Planet

Jue, 11/08/2022 - 14:22
An anonymous reader shares a report: Technology to build cleaner, more efficient air conditioners does exist. Two major AC manufacturers, Daikin and Gree Electric Appliances, shared the top award at last year's Global Cooling Prize, an international competition focused on designing climate-friendly AC tech. Both companies created ACs with higher internal performance that used less environmentally damaging refrigerants; the new units could reduce their impact on the climate by five times. [...] Another strategy is to double down on heat pumps, which are air conditioners that also work in reverse, using vapor compression to absorb and move heat into a home, instead of releasing it outside. Heat pumps usually cost several thousand dollars, though the Inflation Reduction Act includes a proposal for a significant heat pump rebate, and President Joe Biden has invoked the Defense Production Act to ramp up production. Experts have argued installing heat pumps is critical to another important climate goal: transitioning away from fossil fuel-powered furnaces, which are an even bigger source of emissions than cooling. The holy grail of HVAC would be a heat pump that could provide both heating and cooling but isn't dependent on vapor compression. [...] Another challenge, though, is that heat pumps are not the easiest appliance to install, especially for renters, who don't necessarily have the money or ability to invest in bulky HVAC systems. To address this problem, a company called Gradient has designed a heat pump that easily slides over a windowsill -- it doesn't block light -- and currently uses a refrigerant called R32, which is supposed to have a (comparatively) low global warming potential. Gradient recently won a contract to install its units in New York City public housing.

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Arctic Warming Is Happening Faster Than Described, Analysis Shows

Jue, 11/08/2022 - 13:41
The rapid warming of the Arctic, a definitive sign of climate change, is occurring even faster than previously described, researchers in Finland said Thursday. From a report: Over the past four decades the region has been heating up four times faster than the global average, not the commonly reported two to three times. And some parts of the region, notably the Barents Sea north of Norway and Russia, are warming up to seven times faster, they said. The result is faster melting of the Greenland ice sheet, which leads to greater sea-level rise. But it also affects atmospheric circulation in North America and elsewhere, with impacts on weather like extreme rainfall and heat waves, although some of the impacts are a subject of debate among scientists. While scientists have long known that average temperatures in the Arctic are increasing faster than the rest of the planet, the rate has been a source of confusion. Studies and news accounts have estimated it is two to three times faster than the global average. Mika Rantanen, a researcher at the Finnish Meteorological Institute in Helsinki, said he and his colleagues decided to look at the issue in the summer of 2020, when intense heat waves in the Siberian Arctic drew a lot of attention. The new findings are bolstered by those of another recent study, led by scientists at Los Alamos National Laboratory, which found similar rates of warming, although over a different time span.

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