An anonymous reader quotes a report from The Guardian: Writing in the Journal of Neuroscience, Peters and colleagues describe how they recruited 32 healthy men aged between 19 and 33 and gave all of them the same dinner of pasta and veal, an apple and a strawberry yoghurt. Participants were then either sent home to bed wearing a sleep-tracking device, or kept awake in the laboratory all night with activities including parlor games. All returned the next morning to have their hunger and appetite rated, while 29 of the men had their levels of blood sugar measured, as well as levels of certain hormones linked to stress and appetite. Participants also took part in a game in which they were presented with pictures of 24 snack food items, such as chocolate bars, and 24 inedible items, including hats or mugs, and were first asked to rate how much they would be willing to pay for them on a scale. During a functional magnetic resonance imaging (fMRI) scan, they were asked to choose whether or not they would actually buy the object when its price was fixed -- an experiment that allowed researchers to look at participants' brain activity upon seeing pictures of food and other items. A week later, the experiment was repeated, with the participants who had previously stayed up allowed to sleep, and vice versa.

The results showed that whether sleep-deprived or not, participants were similarly hungry in the morning, and had similar levels of most hormones and blood sugar. However, when participants were sleep-deprived, they were willing to pay more for a food snack than when rested, and had higher levels in their blood of a substance called des-acyl ghrelin -- which is related to the "hunger hormone" ghrelin, though its function is not clear. The fMRI results showed that when sleep-deprived, participants had greater activity in the brain's amygdala (where food rewards are processed) when food images were shown, and a stronger link between the price participants would pay for food and activity in the hypothalamus (which is involved in regulating consumption). Interactions between these two regions increased compared with when participants had slept.

Lab-grown meat is becoming closer to a reality. But this new technology poses new questions for people who typically avoid meat for religious or ethical reasons. An anonymous reader shares a report: Lab-grown meat has sparked a debate among rabbis in Israel about whether cell-cultured is the same as conventional meat and should fall under the same guidelines for keeping kosher. "There is a disagreement about it and there is a conversation. Also, definitely, there are new questions about lab-meat," says Rabbi Yuval Cherlow, an expert on kosher tradition and bioethics. WSJ has posted a video in which you can hear more from Rabbi Cherlow.

dmoberhaus writes: An investigation into the decline of America's peyote, a hallucinogenic cactus that is critically important to the rituals of the Native American Church, the largest pan-tribal religious organization in the U.S. Motherboard spoke with Dawn Davis, a researcher using satellite data to track the destruction of peyote's habitat, as well as Salvador Johnson, one of only four people who is licensed to harvest and sell peyote in the U.S. by the DEA. "In 2011, Davis traveled to the peyote gardens for the first time and met with Johnson," reports Motherboard. "Davis said that Johnson was following many conservation best practices, such as cycling through the areas where peyote is harvested, but this hadn't slowed the steady decrease in the size and quantity of peyote buttons in his harvests. Today, the biggest threats to peyote continue to be rapid land development, poaching, and rooting by feral pigs -- problems that responsible harvesting by peyoteros can't solve."

While there has been an increase in the number of indigenous people growing peyote in greenhouses, this is only a temporary solution to the conservation crisis. Davis is advocating for conservation easements or tax breaks for landowners to encourage the protection of peyote. She also said it will be necessary to push for the DEA to reschedule peyote, which is still considered a Schedule I substance that has "no currently accepted medical use." This makes it exceedingly hard for individuals to become licensed peyoteros.

On Sunday night, a comet that orbits between Jupiter and the sun will make its closest approach to Earth in centuries. According to Tony Farnham, a research scientist in the astronomy department at the University of Maryland, the comet will appear as a bright, fuzzy ball with a greenish-gray tint. "You've got a one-kilometer solid nuclear in the middle, and gas is going out hundreds of thousands of miles," says Tony. The comet glows green because the gases emit light in green wavelengths. The New York Times reports: The ball of gas and dust, sometimes referred to as the "Christmas comet," was named 46P/Wirtanen, after the astronomer Carl Wirtanen, who discovered it in 1948. It orbits the sun once every 5.4 years, passing by Earth approximately every 11 years, but its distance varies and it is rarely this close. As the comet passes by, it will be 30 times farther from Earth than the moon, NASA said. The proximity of 46P/Wirtanen provides an opportunity to research the tail of the comet and see farther into the nucleus.

The comet is visible now but it will shine even brighter on Sunday as it reaches its closest approach, 7.1 million miles from Earth. That may sound really far, but it is among the 10 closest approaches by a comet in 70 years, NASA said. Only a few of those could be seen with the naked eye. Don't worry if you miss the comet on Sunday. It should be just as visible for a week or two because its appearance will change gradually. After it moves on, it won't be this close to Earth again for hundreds, if not thousands, of years. Online charts can help pinpoint its location.

"Nearly 200 countries overcame political divisions late on Saturday to agree on rules for implementing a landmark global climate deal," reports Reuters. "After two weeks of talks in the Polish city of Katowice, nations finally reached consensus on a more detailed framework for the 2015 Paris Agreement, which aims to limit a rise in average world temperatures to 'well below' 2 degrees Celsius (3.6 degrees Fahrenheit) above pre-industrial levels." From the report: Before the talks started, many expected the deal would not be as robust as needed. The unity which underpinned the Paris talks has fragmented, and U.S. President Donald Trump intends to pull his country - one of the world's biggest emitters - out of the pact. At the 11th hour, ministers managed to break a deadlock between Brazil and other countries over the accounting rules for the monitoring of carbon credits, deferring the bulk of that discussion to next year, but missing an opportunity to send a signal to businesses to speed up their actions. Still, exhausted ministers managed to bridge a series of divides to produce a 156-page rulebook - which is broken down into themes such as how countries will report and monitor their national pledges to curb greenhouse gas emissions and update their emissions plans.

Not everyone is happy with everything, but the process is still on track and it is something to build on, several ministers said. Some countries and green groups criticized the outcome for failing to urge increased ambitions on emissions cuts sufficiently to curb rising temperatures. Poorer nations vulnerable to climate change also wanted more clarity on how an already agreed $100 billion a year of climate finance by 2020 will be provided and on efforts to build on that amount further from the end of the decade.

schwit1 shared this article from Bloomberg: Brain scans of adolescents who are heavy users of smartphones, tablets and video games look different from those of less active screen users, preliminary results from an ongoing study funded by the National Institutes of Health show, according to a report on Sunday by "60 Minutes." That's the finding of the first batch of scans of 4,500 nine- to 10-year-olds. Scientists will follow those children and thousands more for a decade to see how childhood experiences, including the use of digital devices, affect their brains, emotional development and mental health.

In the first round of testing, the scans of children who reported daily screen usage of more than seven hours showed premature thinning of the brain cortex, the outermost layer that processes information from the physical world.... Early results from the $300 million study, called Adolescent Brain Cognitive Development (ABCD), have determined that children who spend more than two hours of daily screen time score lower on thinking and language tests. A major data release is scheduled for early 2019.
The study's director cautions that "It won't be until we follow them over time that we will see if there are outcomes that are associated with the differences that we're seeing in this single snapshot."

The study will ultimately follow over 11,000 nine- to 10-year-olds for a decade.

Researchers at the University of Geneva Switzerland have used NASA's Hubble telescope to find an exoplanet that's evaporating. The exoplanet, GJ 3470b, shows signs of losing hydrogen in its atmosphere, causing it to shrink. USA Today reports: The study is part of exploration into "hot Neptunes," planets that are the size of Neptune, sit very close to their star, and have atmospheres as hot at 1,700 degrees Fahrenheit, says NASA. Finding a "hot Neptune" is rare because they sit so close to their star and tend to evaporate more quickly. In the case of GJ 3470b, scientists classify it as a "warmer" Neptune because it sits farther away from its star. The exoplanet discovered by astronauts is losing its atmosphere at a rate 100 times faster than a previous "warmer" Neptune planet discovered a few years before, according to a study published Thursday in the journal "Astronomy & Astrophysics." The planet sits 3.7 million miles from its star. For comparison, Earth is 92.9 million miles from the sun. Researchers say these "hot Neptune" planets shrink in size and morph into "Super Earths," versions of our planet that are massive and more rocky.

NASA's Juno mission to the gas giant Jupiter has reached its halfway mark and has revealed new views of cyclones at the poles. The BBC reports: As it orbits the planet every 53 days - Juno performs a science-gathering dive, speeding from pole to pole. Its sensors take measurements of the composition of the planet, in an effort to decipher how the largest world in our Solar System formed. Mapping the magnetic and gravity fields should also expose Jupiter's structure.

But images from JunoCam -- a camera that was intended to capture images that could be shared with the public -- has already given us some surprising insights. "When we made our first pass over the poles, we knew we were seeing a territory on Jupiter we had never seen before," said Dr Candice Hansen, from the Planetary Science Institute in Arizona. "What we did not expect was that we would see these orderly polygons of cyclones; huge storms - twice the size of Texas."

"The Register has an article on the possibility that a supernova or a series of them could explain a mass die-off of marine animals around 2.6 million years ago," writes Slashdot reader KindMind. From the report: A gigantic supernova explosion may have triggered mass extinctions for creatures living in Earth's prehistoric oceans some 2.6 million years ago, according to new research published in Astrobiology. Marine animals like the megalodon [...] suddenly disappeared during the late Pliocene. Around the same time, scientists [...] noticed a peak in the iron-60 isotope in ancient seabeds. "As far back as the mid-1990s, people said, "Hey, look for iron-60. It's a telltale because there's no other way for it to get to Earth but from a supernova.' Because iron-60 is radioactive, if it was formed with the Earth it would be long gone by now. So, it had to have been rained down on us" explained Adrian Melott, lead author of the paper and a physics and astronomy professor at the University of Kansas.

The team believes that a supernova located 150 light years away set of a chain of supernovae bursts and covered the Earth in a shroud of deadly cosmic ray radiation. This was amplified, Melott said, because the Solar System is right on the edge of an area of the interstellar medium called the Local Bubble. The Local Bubble extends about 300 light years across and contains the two main clouds of dust and gas: Local Interstellar Cloud and the G-Cloud. As the supernovae ejected cosmic rays, these beams of energetic particles would have repeatedly bounced off the clouds to create a "cosmic-ray bath" that could have lasted 10,000 to 100,000 years. Some of that radiation such as cosmic ray muons would have leaked onto Earth, and over time it could have led to genetic mutations and cancers [that would have caused animals like the megalodon to die off prematurely].

An anonymous reader quotes a report from The Guardian: Surgical instruments used in brain operations should be treated to ensure they are not contaminated with proteins linked to Alzheimer's disease, according to scientists who found evidence that they may be spread by certain medical procedures. The researchers urged doctors to decontaminate neurosurgical tools more thoroughly as a precautionary measure to reduce the potential risk of spreading abnormal proteins known to build up in the brains of Alzheimer's patients. Prof John Collinge, director of the Medical Research Council prion unit at University College London, said that while Alzheimer's disease was not contagious, there was a slim risk that harmful proteins that drive the disease could spread through brain surgery and other rare procedures.

The latest test flight by Sir Richard Branson's Virgin Galactic successfully rocketed to space and back. From a report: The firm's SpaceShipTwo passenger rocket ship reached a height of 82.7km, beyond the altitude at which space is said to begin. It marked the plane's fourth test flight and followed earlier setbacks in the firm's space programme. Sir Richard is in a race with Elon Musk and Jeff Bezos to send the first fee-paying passengers into space. He founded the commercial spaceflight company in 2004, shortly after Mr Musk started SpaceX and Jeff Bezos established Blue Origin. In 2008, Virgin Galactic first promised sub-orbital spaceflight trips for tourists would be taking place "within 18 months". It has since regularly made similar promises to have space flights airborne in the near future.

According to a new report released on Tuesday by the U.S. National Oceanographic and Atmospheric Administration, the Arctic had its second-hottest year on record in 2018. "Arctic air temperatures for the past five years have exceeded all previous records since 1900," according to the annual NOAA study, the 2018 Arctic Report Card, which said the year was second only to 2016 in overall warmth in the region. Reuters reports: The study said the Arctic warming continues at about double the rate of the rest of the planet, and that the trend appears to be altering the shape and strength of the jet stream air current that influences weather in the Northern Hemisphere. "Growing atmospheric warmth in the Arctic results in a sluggish and unusually wavy jet-stream that coincided with abnormal weather events," it said, noting that the changing patterns have often brought unusually frigid temperatures to areas south of the Arctic Circle. Some examples are "a swarm of severe winter storms in the eastern United States in 2018, and the extreme cold outbreak in Europe in March 2018 known as 'the Beast from the East.'"

Chemists have found a material that can display superconducting behavior at a temperature warmer than it currently is at the North Pole. The work brings room-temperature superconductivity tantalizingly close.

From a report: The work comes from the lab of Mikhail Eremets and colleagues at the Max Planck Institute for Chemistry in Mainz, Germany. Eremets and his colleagues say they have observed lanthanum hydride (LaH10) superconducting at the sweltering temperature of 250 K, or -23C. That's warmer than the current temperature at the North Pole.

"Our study makes a leap forward on the road to the room-temperature superconductivity," say the team. (The caveat is that the sample has to be under huge pressure: 170 gigapascals, or about half the pressure at the center of the Earth.)

"South Australia, which has a history with space events long ago, is set to become the base for the Australian space industry," writes Slashdot reader Badooleoo. ABC News reports: Prime Minister Scott Morrison has announced Adelaide will be the home of Australia's new space agency. South Australia beat strong competition from other states to secure the headquarters, after enlisting homegrown NASA astronaut Andy Thomas to help with its campaign. The agency will be based at Lot Fourteen, the former Royal Adelaide Hospital site, which is being transformed into an innovation precinct. The Prime Minister said South Australia was an ideal home for the new agency and was already a key hub for the space and technology industry. "This agency is going to open doors for local businesses and Australian access to the $US345 billion global space industry," Prime Minister Scott Morrison said. "Our Government's $41 million investment into the agency will act as a launching pad to triple Australia's space economy to $12 billion and create up to 20,000 jobs by 2030."

The Earth is far more alive than previously thought, according to "deep life" studies that reveal a rich ecosystem beneath our feet that is almost twice the size of that found in all the world's oceans. From a report: Despite extreme heat, no light, minuscule nutrition and intense pressure, scientists estimate this subterranean biosphere is teeming with between 15bn and 23bn tonnes of micro-organisms, hundreds of times the combined weight of every human on the planet. Researchers at the Deep Carbon Observatory say the diversity of underworld species bears comparison to the Amazon or the Galapagos Islands, but unlike those places the environment is still largely pristine because people have yet to probe most of the subsurface.

"It's like finding a whole new reservoir of life on Earth," said Karen Lloyd, an associate professor at the University of Tennessee in Knoxville. "We are discovering new types of life all the time. So much of life is within the Earth rather than on top of it." The team combines 1,200 scientists from 52 countries in disciplines ranging from geology and microbiology to chemistry and physics. A year before the conclusion of their 10-year study, they will present an amalgamation of findings to date before the American Geophysical Union's annual meeting opens this week.

The Voyager 2 probe, which left Earth in 1977, has become the second human-made object to leave our Solar System. From a report: It was launched 16 days before its twin craft, Voyager 1, but that probe's faster trajectory meant that it was in "the space between the stars" six years before Voyager 2. The news was revealed at the American Geophysical Union (AGU) meeting in Washington. And chief scientist on the mission, Prof Edward Stone, confirmed it.

He said both probes had now "made it into interstellar space" and that Voyager 2's date of departure from the Solar System was 5 November 2018. On that date, the steady stream of particles emitted from the Sun that were being detected by the probe suddenly dipped. This indicated that it had crossed the "heliopause" -- the term for the outer edge of the Sun's protective bubble of particles and magnetic field. And while its twin craft beat it to this boundary, the US space agency says that Voyager 2 has a working instrument aboard that will provide "first-of-its-kind observations of the nature of this gateway into interstellar space".

In a space no longer than 500 metres, researchers say they recorded at least 195 different species of corals. From a report: A team of researchers says it has discovered the most diverse coral site ever recorded on the Great Barrier Reef. Great Barrier Reef Legacy, a non-profit organisation that conducts research trips on the reef, and scientist Charlie Veron, known as the godfather of coral, have identified the site on the outer reef. In a space no longer than 500 metres, the researchers say they recorded at least 195 different species of corals on a research expedition last month. The group first stumbled upon the site on a voyage last year, and returned in November to conduct studies.

"I've spent eight years working on the Great Barrier Reef in just about every nook and cranny," Veron said. "I thought there would be nothing new for me on the Great Barrier Reef." Veron returned with the group to record the corals and will write a paper on the site. He said it was located in a general area that had been affected by widespread coral bleaching and coral mortality and it would take further work to assess why this particular spot had survived so far. It also appeared to have been unaffected by cyclones and other factors such as crown of thorns that threaten coral health.

Salts that de-ice roads, parking lots and sidewalks keep people safe in winter. But new research shows they are contributing to a sharp and widely rising problem across the U.S. From a report: At least a third of the rivers and streams in the country have gotten saltier in the past 25 years. And by 2100, more than half of them may contain at least 50 percent more salt than they used to. Increasing salinity will not just affect freshwater plants and animals but human lives as well -- notably, by affecting drinking water. Sujay Kaushal, a biogeochemist at the University of Maryland, College Park, recounts an experience he had when visiting relatives in New Jersey. When getting a drink from the tap, "I saw a white film on the glass." After trying to scrub it off, he found, "it turned out to be a thin layer of salt crusting the glass."

When Kaushal, who studies how salt invades freshwater sources, sampled the local water supply he found not just an elevated level of the sodium chloride, widely used in winter to de-ice outdoor surfaces, but plenty of other salts such as sodium bicarbonate and magnesium chloride. He also found similar concentrations of these chemicals in most rivers along the east coast, including the Potomac, which provides drinking water for Washington, D.C. Where did all of it come from? De-icing salts, Kaushal determined, are part of the problem, slowly corroding our infrastructure.

"Strange waves rippled across earth and only one person spotted them," reported Forbes, noting that the seismologist then "quickly put out an alert to see if other systems detected the same unusual wave."

"Seismographs picked up the waves as they traveled as far as New Zealand, Chile, Hawaii and Canada. In total, the waves were detected as far as 11,000 miles from their origin, ringing for 20 minutes or more minutes as they passed... As these waves rippled across the globe there were surprisingly no reports of anyone feeling the rumbling."

The Weather Channel now reports that "There was no earthquake large enough to have started these low-frequency signals. Scientists believed a magma shift caused the rumblings," citing a recent interview with Stephen Hicks, a seismologist at the University of Southampton. The Guardian reports: Hicks believes magma may suddenly have drained from a volcanic chamber about 10 miles under the seafloor near Mayotte, setting off the deep rumble that spread around the world. While strong enough to be picked up by sensitive seismometers, the vibrations would have been minuscule: far smaller than a millimetre. "It's something that you wouldn't perceive," he said. Pierre Briole, a geoscientist at Ecole Normale Superieure in Paris, has reached a similar conclusion. He believes that a third of a cubic mile of magma may have drained from a volcanic chamber under the seafloor, unleashing deep vibrations when its roof collapsed.

Much of the seismic sleuthing played out on social media with professional and amateur scientists working together. "Overall, [it has been] a fascinating demonstration of open science on Twitter and engagement between scientists and citizen seismologists," said Hicks.

An anonymous reader quotes a report from The Guardian: Rapid global warming caused the largest extinction event in the Earth's history, which wiped out the vast majority of marine and terrestrial animals on the planet, scientists have found. The mass extinction, known as the "great dying," occurred around 252m years ago and marked the end of the Permian geologic period. The study of sediments and fossilized creatures show the event was the single greatest calamity ever to befall life on Earth, eclipsing even the extinction of the dinosaurs 65m years ago. Up to 96% of all marine species perished while more than two-thirds of terrestrial species disappeared. The cataclysm was so severe it wiped out most of the planet's trees, insects, plants, lizards and even microbes.

The researchers used paleoceanographic records and built a model to analyze changes in animal metabolism, ocean and climate conditions. When they used the model to mimic conditions at the end of the Permian period, they found it matched the extinction records. According to the study, this suggests that marine animals essentially suffocated as warming waters lacked the oxygen required for survival. The great dying event, which occurred over an uncertain timeframe of possibly hundreds of years, saw Earth's temperatures increase by around 10C (18F). Oceans lost around 80% of their oxygen, with parts of the seafloor becoming completely oxygen-free. Scientists believe this warming was caused by a huge spike in greenhouse gas emissions, potentially caused by volcanic activity.