Education

Poor Grades Tied To Class Times That Don't Match Our Biological Clocks (berkeley.edu) 294

An anonymous reader shares a report: It may be time to tailor students' class schedules to their natural biological rhythms, according to a new study from UC Berkeley and Northeastern Illinois University. Researchers tracked the personal daily online activity profiles of nearly 15,000 college students as they logged into campus servers. After sorting the students into "night owls," "daytime finches" and "morning larks" -- based on their activities on days they were not in class -- researchers compared their class times to their academic outcomes. Their findings, published today in the journal Scientific Reports, show that students whose circadian rhythms were out of sync with their class schedules -- say, night owls taking early morning courses -- received lower grades due to "social jet lag," a condition in which peak alertness times are at odds with work, school or other demands. "We found that the majority of students were being jet-lagged by their class times, which correlated very strongly with decreased academic performance," said study co-lead author Benjamin Smarr, a postdoctoral fellow who studies circadian rhythm disruptions in the lab of UC Berkeley psychology professor Lance Kriegsfeld.
Space

An Up-Close Look At the Parker Solar Probe -- the Spacecraft That Will Skim the Sun's Surface (arstechnica.com) 121

schwit1 shares a report from Ars Technica, offering an up-close look at the Parker Solar Probe: This summer, NASA will launch the Parker Solar Probe, an impressively heat-resistant spacecraft destined to glide closer to the surface of the Sun than any spacecraft before it. It will fly within about 6 million kilometers of the searing surface, more than seven times closer than earlier craft. If all goes to plan, the craft will be hurtling at 724,205 km per hour and have its one-of-a-kind heat shield perfectly facing the surface as it makes those closest approaches. In about seven years, it will complete 24 orbits around the Sun and pass by Venus seven times. All the while, the Parker probe will collect a constellation of data to help answer scientists' burning questions -- and solve some sizzling mysteries -- about the orb of hot plasma that lights up our Solar System. Namely, it will try to help us finally understand why the Sun's atmosphere is 300 times hotter than its surface, which itself is a balmy 5,727C. This fact defies basic physics and to this day is unexplained. One of the leading hypotheses to account for the heat shift comes from famed physicist Eugene Parker, after whom the probe is named. In the mid-1950s, Parker theorized that the Sun's super-heated corona could be explained by a complex system of plasma, magnetic fields, and energetic particles that spark solar explosions called "nanoflares." Scientists are thirsty for close-up data on those potential explosions as well as the cascade of energy called solar wind. With that data, they can put their hypotheses to the test. And in addition to helping us understand coronal heat, data on these sunny phenomena could help clear up poorly understood space weather, which can wreak havoc on satellites and power lines here on Earth.
Math

Scientists Explain the Sound of Knuckle Cracking (bbc.com) 86

"The BBC reports on something sure to impress your next date -- and possibly your last -- when you explain it," writes Slashdot reader dryriver. From the report: Scientists have turned their attention to investigating that most annoying of human habits -- the sound made when you crack your knuckles. The characteristic pop can be explained by three mathematical equations, say researchers in the US and France. Their model confirms the idea that the cracking sound is due to tiny bubbles collapsing in the fluid of the joint as the pressure changes. Surprisingly, perhaps, the phenomenon has been debated for around a century. Science student Vineeth Chandran Suja was cracking his knuckles in class in France when he decided to investigate.

"The first equation describes the pressure variations inside our joint when we crack our knuckles," he told BBC News. "The second equation is a well-known equation which describes the size variations of bubbles in response to pressure variations. And the third equation that we wrote down was coupling the size variation of the bubbles to ones that produce sounds." The equations make up a complete mathematical model that describes the sound of knuckle cracking, said Chandran Suja, who is now a postgraduate student at Stanford University in California. "When we crack our knuckles we're actually pulling apart our joints," he explained. "And when we do that the pressure goes down. Bubbles appear in the fluid, which is lubricating the joint -- the synovial fluid. "During the process of knuckle cracking there are pressure variations in the joint which causes the size of the bubbles to fluctuate extremely fast, and this leads to sound, which we associate with knuckle cracking.''
The study has been published in the journal Scientific Reports.
Space

FCC Authorizes SpaceX's Ambitious Satellite Internet Plans 102

The Federal Communications Commission on Thursday approved an application by Elon Musk's SpaceX, allowing the aerospace company to provide broadband services using satellites in the U.S. and worldwide. "With this action, the Commission takes another step to increase high-speed broadband availability and competition in the United States," the FCC said in a statement. CNBC reports: This marks the first time the FCC has allowed a U.S.-licensed satellite constellation to provide broadband services through low-Earth orbit satellites. "We appreciate the FCC's thorough review and approval of SpaceX's constellation license. Although we still have much to do with this complex undertaking, this is an important step toward SpaceX building a next-generation satellite network that can link the globe with reliable and affordable broadband service, especially reaching those who are not yet connected," Gwynne Shotwell, President and Chief Operating Officer at SpaceX said in a statement.

SpaceX will begin launching the constellation it dubbed "Starlink" in 2019. The system will be operational once at least 800 satellites are deployed. Starlink will offer broadband speeds comparable to fiber optic networks.The satellites would offer new direct to consumer wireless connections, rather the present system's redistribution of signals, transforming a traditionally high-cost, low reliability service.
Science

X-ray 'Ghost Images' Could Cut Radiation Doses (sciencemag.org) 21

Sophia Chen, writing for Science magazine: On its own, a single-pixel camera captures pictures that are pretty dull: squares that are completely black, completely white, or some shade of gray in between. All it does, after all, is detect brightness. Yet by connecting a single-pixel camera to a patterned light source, a team of physicists in China has made detailed x-ray images using a statistical technique called ghost imaging, first pioneered 20 years ago in infrared and visible light. Researchers in the field say future versions of this system could take clear x-ray photographs with cheap cameras -- no need for lenses and multipixel detectors -- and less cancer-causing radiation than conventional techniques.

"Our system is much smaller and cheaper, and it could even be portable if you needed to take it into the field," says Wu Ling-An, a physicist at the Chinese Academy of Sciences in Beijing whose work with her colleagues was published on 28 March in Optica. The researchers' system still isn't ready to be used in medicine. But they have lowered the x-ray dose by about a million times compared with earlier attempts, says Daniele Pelliccia, who in 2015 made some of the first x-ray ghost images.

China

China, in Search of Water, is Building a Rain-Making Network Three Times the Size of Spain (scmp.com) 111

China is testing cutting-edge defence technology to develop a powerful yet relatively low-cost weather modification system to bring substantially more rain to the Tibetan plateau, Asia's biggest freshwater reserve. From a report: The system, which involves an enormous network of fuel-burning chambers installed high up on the Tibetan mountains, could increase rainfall in the region by up to 10 billion cubic metres a year -- about 7 per cent of China's total water consumption -- according to researchers involved in the project. Tens of thousands of chambers will be built at selected locations across the Tibetan plateau to produce rainfall over a total area of about 1.6 million square kilometres (620,000 square miles), or three times the size of Spain. It will be the world's biggest such project.

The chambers burn solid fuel to produce silver iodide, a cloud-seeding agent with a crystalline structure much like ice. The chambers stand on steep mountain ridges facing the moist monsoon from south Asia. As wind hits the mountain, it produces an upward draft and sweeps the particles into the clouds to induce rain and snow.

Science

Consumer Genetic Tests May Have a Lot of False Positives (theverge.com) 99

A new study, published in the journal Genetics in Medicine, found that consumer genetic tests bring up a lot of false positives. "In this case, 40 percent of the results from the consumer tests were false positives," reports The Verge, noting that the findings "cover a very small sample size and don't show that consumer tests always have a 40 percent false positive rate." From the report: The research was done by scientists at Ambry Genetics, a medical laboratory in California. By looking through their own database, they found that 49 people had been referred to them because of some worrying results from their consumer genetic tests. Still, scientists at Ambry were able to confirm only 60 percent of the results when they compared the raw data from consumer tests with more thorough genetic tests done by themselves and other clinical laboratories. So, 40 percent of variants in a variety of genes reported in DTC raw data were false positives, meaning that they said a genetic variant was there when it wasn't. (Most of these turned out to be variants linked to cancer.) Additionally, the authors write, some variants classified as "increased risk" were not only classified as "benign" by clinical laboratories, but they were actually common variants.
Space

Galaxy Without Any Dark Matter Baffles Astronomers (arstechnica.com) 200

A distant galaxy that appears completely devoid of dark matter has baffled astronomers and deepened the mystery of the universe's most elusive substance. The Guardian reports: The absence of dark matter from a small patch of sky might appear to be a non-problem, given that astronomers have never directly observed dark matter anywhere. However, most current theories of the universe suggest that everywhere that ordinary matter is found, dark matter ought to be lurking too, making the newly observed galaxy an odd exception. Dark matter's existence is inferred from its gravitational influence on visible objects, which suggests it dominates over ordinary matter by a ratio of 5:1. Some of the clearest evidence comes from tracking stars in the outer regions of galaxies, which consistently appear to be orbiting faster than their escape velocity, the threshold speed at which they ought to break free of the gravitational binds holding them in place and slingshot into space. This suggests there is unseen, but substantial, mass holding stars in orbit. In the Milky Way there is about 30 times more dark matter than normal matter. The latest observations focused on an ultra-diffuse galaxy -- ghostly galaxies that are large but have hardly any stars -- called NGC 1052-DF2. The team tracked the motions of 10 bright star clusters and found that they were traveling way below the velocities expected. The velocities gave an upper estimate for the galactic mass of 400 times lower than expected. The researchers described their discovery in the journal Nature.
AI

New Deep-Learning Software Knows How To Make Desired Organic Molecules (nature.com) 46

dryriver shares a report from Nature about a neural network-based, deep-learning software that is as good as trained chemists in figuring out what reagents and reactions may lead to the successful creation of a desired organic molecule: Chemists have a new lab assistant: artificial intelligence. Researchers have developed a "deep learning" computer program that produces blueprints for the sequences of reactions needed to create small organic molecules, such as drug compounds. The pathways that the tool suggests look just as good on paper as those devised by human chemists. The tool, described in Nature on March 28, is not the first software to wield artificial intelligence (AI) instead of human skill and intuition. Yet chemists hail the development as a milestone, saying that it could speed up the process of drug discovery and make organic chemistry more efficient. Chemists have conventionally scoured lists of reactions recorded by others, and drawn on their own intuition to work out a step-by-step pathway to make a particular compound. They usually work backwards, starting with the molecule they want to create and then analyzing which readily available reagents and sequences of reactions could be used to synthesize it -- a process known as retrosynthesis, which can take hours or even days of planning. The new AI tool, developed by Marwin Segler, an organic chemist and artificial-intelligence researcher at the University of Munster in Germany, and his colleagues, uses deep-learning neural networks to imbibe essentially all known single-step organic-chemistry reactions -- about 12.4 million of them. This enables it to predict the chemical reactions that can be used in any single step. The tool repeatedly applies these neural networks in planning a multi-step synthesis, deconstructing the desired molecule until it ends up with the available starting reagents.
Medicine

Meet the Interstitium, the Largest Organ We Never Knew We Had (thedailybeast.com) 208

An anonymous reader quotes a report from The Daily Beast: A study published in Scientific Reports on Tuesday suggests that a previously unknown organ has been found in the human body. More astonishingly, the paper puts forth the idea that this new organ is the largest by volume among all 80 organs -- if what the researchers found is, in fact, an organ. The new organ, [pathologist Neil Theise] explained, was a thin layer of dense connective tissue throughout the body, sandwiched just under our skin and within the middle layer of every visceral organ. The organ also made up all the fascia, or the thin mesh of tissue separating every muscle and all the tissue around every vein and artery, from largest to smallest. What initially seemed to be a solid, dense, connective tissue layer was actually a complex network of fluid-filled cavities that are strong and flexible, yet so tiny and undiscerning that they escaped the attention of the brightest scientific minds for generations. In fact, Theise expanded, this "interstitium" could explain many of modern medicine's mysteries, often dismissed by the establishment as either silly or explainable by other phenomena. Take acupuncture, Theise said -- that energetic healing jolt may be traced to the interstitium. Or perhaps the interstitium acted as a "shock absorber," something that protected other organs and muscles in daily function. Also, the space is in direct communication with the lymphatic system as the origin of lymph fluid -- which means the interstitium's system of fluid-filled backroads could explain the metastasis of cancer cells and their quick spread beyond the limits of the organ in which the cancer started.
NASA

James Webb Space Telescope, NASA's Next Hubble, Delayed Again (cnet.com) 83

NASA has been planning to launch a powerful new telescope that can see across the universe and perhaps to the beginning of time for many years now. But the launch of the James Webb Space Telescope (JWST) appears likely to have to wait at least two more. From a report: On Tuesday, NASA said it needs more time to test the $8 billion space observatory, pushing back the scheduled launch date to approximately May 2020 from the earlier plans of next year. "Webb is the highest priority project for the agency's Science Mission Directorate, and the largest international space science project in US history," Robert Lightfoot, NASA's acting administrator, said in a release. "All the observatory's flight hardware is now complete, however, the issues brought to light with the spacecraft element are prompting us to take the necessary steps to refocus our efforts on the completion of this ambitious and complex observatory."
Data Storage

Wind and Solar Can Power Most of the United States, Says Study (theguardian.com) 417

An anonymous reader writes: The Guardian reports of a recent paper, published in the journal Energy and Environmental Science, that helps explain how wind and solar energy can power most of the United States: "The authors analyzed 36 years of hourly weather data (1980-2015) in the U.S. They calculated the available wind and solar power over this time period and also included the electrical demand in the U.S. and its variation throughout the year. With this information, the researchers considered two scenarios. In scenario 1, they imagined wind and solar installations that would be sufficient to supply 100% of the U.S. electrical needs. In the second scenario, the installations would be over-designed; capable of providing 150% of the total U.S. electrical need. But the authors recognize that just because a solar panel or a wind turbine can provide all our energy, it doesn't mean that will happen in reality. It goes back to the prior discussion that sometimes the wind just doesn't blow, and sometimes the sun isn't shining. With these two scenarios, the authors then considered different mixes of power, from all solar to all wind. They also included the effect of aggregation area, that is, what sized regions are used to generate power. Is your power coming from wind and solar in your neighborhood, your city, your state or your region?

The authors found that with 100% power capacity and no mechanism to store energy, a wind-heavy portfolio is best (about 75% wind, 25% solar) and using large aggregate regions is optimal. It is possible to supply about 75-80% of U.S. electrical needs. If the system were designed with excess capacity (the 150% case), the U.S. could meet about 90% of its needs with wind and solar power. The authors modified their study to allow up to 12 hours of US energy storage. They then found that the 100% capacity system fared even better (about 90% of the country's energy) and the optimal balance was now more solar (approximately 70% solar and 30% wind). For the over-capacity system, the authors found that virtually all the country's power needs could be met with wind, solar, and storage."

Earth

More Than 75 Percent of Earth's Land Areas Are 'Broken,' Major Report Finds (vice.com) 145

Like a broken cell phone that can only text or take pictures, but not make a single call, more than 75 percent of the Earth's land areas have lost some or most of their functions, undermining the well-being of the 3.2 billion people that rely on them to produce food crops, provide clean water, control flooding and more. From a report: These once-productive lands have either become deserts, are polluted, or have been deforested and converted for unsustainable agricultural production. This is a major contributor to increased conflict and mass human migration, and left unchecked, could force as many as 700 million to migrate by 2050, according to the world's first comprehensive evidence-based assessment of land degradation, released today in MedellÃn, Colombia.

Land degradation -- including deforestation, soil erosion, and salinity and pollution of fresh water systems -- is also driving species to extinction and aggravating the effects of climate change, the report concludes. It was written by more than 100 leading experts from 45 countries for the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES). IPBES is the 'IPCC for biodiversity,' a scientific assessment of the status of non-human life that makes up the Earth's life support system.

Earth

Flat-Earther's Steam-Powered Rocket Lofts Him 1,875 Feet Up Into Mojave Desert (latimes.com) 410

An anonymous reader quotes a report from Los Angeles Times: "Mad" Mike Hughes, the rocket man who believes the Earth is flat, propelled himself about 1,875 feet into the air Saturday before a hard landing in the Mojave Desert. He told the Associated Press that outside of an aching back he's fine after the launch near Amboy, Calif. The launch in the sparsely populated desert town about 150 miles east of Los Angeles -- was originally scheduled in November. It was scrubbed several times due to logistical issues with the Bureau of Land Management and mechanical problems that kept popping up. The 61-year-old limo driver converted a mobile home into a ramp and modified it to launch from a vertical angle so he wouldn't fall back to the ground on public land. For months he's been working on overhauling his rocket in his garage. It looked like Saturday might be another in a string of cancellations, given that the wind was blowing and his rocket was losing steam. Ideally, they wanted it at 350 psi for maximum thrust, but it was dropping to 340. Sometime after 3 p.m. PDT, and without a countdown, Hughes' rocket soared into the sky. Hughes reached a speed that Stakes estimated to be around 350 mph before pulling his parachute. Hughes was dropping too fast, though, and he had to deploy a second one. He landed with a thud and the rocket's nose broke in two places like it was designed to do.
Medicine

Breakthrough Study Reveals How LSD Dissolves a Person's Sense of Self (newatlas.com) 119

New submitter future guy shares a report from New Atlas: A fascinating study led by scientists at the University of Zurich has uncovered key insights into the mechanisms behind how our brain generates our sense of self. The researchers administered lysergic acid diethylamide (LSD) to several participants in order to home in on where in the brain our sense of self is activated and what happens when a powerful psychedelic drug interferes with that process. The study administered 24 subjects either LSD, LSD in combination with ketanserin, or a placebo. Ketanserin is a compound that is known to inhibit many of the effects of LSD by blocking the serotonin 2A receptor (5-HT2A receptor). Each subject lay in an MRI scanner while undergoing a series of social interaction simulations with a virtual avatar. As well as the brain imaging, the subjects' eye movements were monitored to track when they were or were not following the gaze of the virtual avatar.

The study demonstrated LSD-altered brain activity in several regions previously identified as fundamental for developing coherent self-representation during social interaction, including the posterior cingulate cortex, medial prefrontal cortex and the angular gyrus. Most importantly though was the observation that ketanserin normalized the effects of LSD to the point where the group influenced by ketanserin and LSD displayed similar results to those under the effect of the placebo. These results strongly suggest that the 5-HT2A receptor plays a fundamental role in the development of self-awareness, and differentiation between the self and others. The value of this research is two-fold. As well as simply increasing our knowledge of how the brain functions under the influence of psychedelic drugs, it is suggested that different psychiatric conditions could be treated by manipulating the 5-HT2A receptor pathways.
The study has been published in the journal JNeurosci.
Open Source

Ask Slashdot: Can FOSS Help In the Fight Against Climate Change? 154

dryriver writes: Before I ask my question, there already is free and open-source software (FOSS) for wind turbine design and simulation called QBlade. It lets you calculate turbine blade performance using nothing more than a computer and appears compatible with Xfoil as well. But consider this: the ultimate, most efficient and most real-world usable and widely deployable wind turbine rotor may not have traditional "blades" or "foils" at all, but may be a non-propeller-like, complex and possibly rather strange looking three-dimensional rotor of the sort that only a 3D printer could prototype easily. It may be on a vertical or horizontal axis. It may have air flowing through canals in its non-traditional structure, rather than just around it. Nobody really knows what this "ultimate wind turbine rotor" may look like.

The easiest way to find such a rotor might be through machine-learning. You get an algorithm to create complex non-traditional 3D rotor shapes, simulate their behavior in wind, and then mutate the design, simulate again, and get a machine learning algorithm to learn what sort of mutations lead to a better performing 3D rotor. In theory, enough iterations -- perhaps millions or more -- should eventually lead to the "ultimate rotor" or something closer to it than what is used in wind turbines today. Is this something FOSS developers could tackle, or is this task too complex for non-commercial software? The real world impact of such a FOSS project could be that far better wind turbines can be designed, manufactured and deployed than currently exist, and the fight against climate change becomes more effective; the better your wind turbines perform, and the more usable they are, the more of a fighting chance humanity has to do something against climate change. Could FOSS achieve this?
AI

Hilarious (and Terrifying?) Ways Algorithms Have Outsmarted Their Creators (popularmechanics.com) 75

"Robot brains will challenge the fundamental assumptions of how we humans do things," argues Popular Mechanics, noting that age-old truism "that computers will always do literally, exactly what you tell them to." A paper recently published to ArXiv highlights just a handful of incredible and slightly terrifying ways that algorithms think... An AI project which pit programs against each other in games of five-in-a-row Tic-Tac-Toe on an infinitely expansive board surfaced the extremely successful method of requesting moves involving extremely long memory addresses which would crash the opponent's computer and award a win by default...

These amusing stories also reflect the potential for evolutionary algorithms or neural networks to stumble upon solutions to problems that are outside-the-box in dangerous ways. They're a funnier version of the classic AI nightmare where computers tasked with creating peace on Earth decide the most efficient solution is to exterminate the human race. The solution, the paper suggests, is not fear but careful experimentation.

The paper (available as a free download) contains 27 anecdotes, which its authors describe as a "crowd-sourced product of researchers in the fields of artificial life and evolutionary computation. Popular Science adds that "the most amusing examples are clearly ones where algorithms abused bugs in their simulations -- essentially glitches in the Matrix that gave them superpowers."
Biotech

Researchers Test Tooth-Mounted Sensor-Enabled Chips (go.com) 28

Researchers at Tufts University are testing tooth-mounted RFID chips which sense and transmit data on what goes in your mouth. ABC News reports: The sensors looks like custom microchips stuck to the tooth. They are flexible, tiny squares -- ranging from 4 mm by 4 mm to an even smaller size of about 2 mm by 2 mm -- that are applied directly to human teeth. Each one has three active layers made of titanium and gold, with a middle layer of either silk fibers or water-based gels. In small-scale studies, four human volunteers wore sensors, which had silk as the middle "detector" layer, on their teeth and swished liquids around in their mouths to see if the sensors would function. The researchers were testing for sugar and for alcohol.

The tiny squares successfully sent wireless signals to tablets and cell phone devices. In one of their first experiments, the chip could tell the difference between solutions of purified water, artificial saliva, 50 percent alcohol and wood alcohol. It would then wirelessly signal to a nearby receiver via radiofrequency, similar to how EZ Passes work. They demonstrated that different concentrations of glucose, a type of sugar, could be distinguished, even in liquids that had sugar concentrations like those found in fruit drinks.

Biotech

Can We Fight Drug-Resistant Bacteria With Non-Antibiotic Drugs? (economist.com) 62

Slashdot reader Bruce66423 shares what researchers learned by studying the effect of drugs on bacteria in the gut: The research reveals that it's not just antibiotics that have the effect of causing resistance to antibiotics. "Of the drugs in the study, 156 were antibacterials (144 antibiotics and 12 antiseptics). But a further 835, such as painkillers and blood-pressure pills, were not intended to harm bacteria. Yet almost a quarter (203) did....

"However, Dr Maier's study also brings some good news for the fight against antimicrobial resistance. Some strains she looked at which were resistant to antibiotics nevertheless succumbed to one or more of the non-antibiotic drugs thrown at them. This could be a starting point for the development of new antimicrobial agents which would eliminate bacteria that have proved intractable to other means."

Every drug the researchers tested has already been approved for human use -- which means they could all eventually be used as a second wave of antibiotics.
Medicine

British Scientists Develop Wearable MRI Scanner (wcax.com) 29

British scientists have invented a new type of brain scanner that patients can wear on their head allowing them to move while being tested. "Neuroscientists will be able to envisage a whole new world of experiments where we try to work out what a brain is doing but whilst a person is behaving naturally," said Matt Brookes, a physicist at the University of Nottinham. CBS reports: The device, which looks like a prop from a budget sci-fi movie or phantom of the opera, is in fact the latest thing in brain scanning. "I think in terms of mapping brain activity, brain function, this represents a step change," said Brookes. Because you can do this while wearing it -- play bat and ball, or even drink a cup of tea. It was at Nottingham University in the early 70s that the MRI was first developed. Now the wearable 'MEG' system has the potential to open a whole new field of brain scanning. The scanner records the magnetic field produced by brain activity and can show precisely where in the brain these movements are being controlled. The area of the brain shown in blue is where wrist and arm movements are controlled while playing bat and ball.

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