Slashdot Mirror

A new study has revealed a "fast-acting neural circuit allowing gut cells to communicate with the brain in just seconds," reports New Atlas. Diego Bohorquez, senior author of the study, says "these findings are going to be the biological basis of a new sense. One that serves as the entry point for how the brain knows when the stomach is full of food and calories." He says it "brings legitimacy to [the] idea of the 'gut feeling' as a sixth sense." The study has been published in the journal Science. From the report: Remarkable new work from a team of researchers at Duke University has now revealed a previously unknown direct circuit between the gut and the brain that could allow for fast sensory communication that doesn't relay on laborious hormonal signaling. The research began with a big discovery in 2015 revealing that enteroendocrine cells, the cells in our gut thought to be the primary sensory receptor that communicate with the brain, actually contained nerve endings that seemed like they could directly synaptically communicate with vagal neurons and subsequently, the brain.

The new study first revealed that direct, and near instant, communication occurred between the gut and brain. A mouse was administered with a rabies virus that had been engineered with a green fluorescent tag. Tracing the signal of communication as the gut informed the brain of this virus revealed an immediate response in the vagus nerve. In under 100 milliseconds a single signal was seen to travel from the gut to the brainstem. In order to understand this new neural circuit, the team grew enteroendocrine cells in a lab dish alongside vagal nerve neurons. Not only did these two elements rapidly demonstrate communication, but it was discovered that glutamate, a foundational neurotransmitter, modulated the rate of transmission. What this experiment impressively revealed was that enteroendocrine cells don't solely signal to the brain via hormonal triggers, but also can directly communicate via neural synapses.

In a study published in Science Advances, researchers in Drexel's College of Engineering describe a method for spraying invisibly thin antennas, made from a type of two-dimensional, metallic material called MXene, that perform as well as those being used in mobile devices, wireless routers and portable transducers. Phys.Org reports: The researchers, from the College's Department of Materials Science and Engineering, report that the MXene titanium carbide can be dissolved in water to create an ink or paint. The exceptional conductivity of the material enables it to transmit and direct radio waves, even when it's applied in a very thin coating. Preserving transmission quality in a form this thin is significant because it would allow antennas to easily be embedded -- literally, sprayed on -- in a wide variety of objects and surfaces without adding additional weight or circuitry or requiring a certain level of rigidity.

Initial testing of the sprayed antennas suggest that they can perform with the same range of quality as current antennas, which are made from familiar metals, like gold, silver, copper and aluminum, but are much thicker than MXene antennas. Making antennas smaller and lighter has long been a goal of materials scientists and electrical engineers, so this discovery is a sizable step forward both in terms of reducing their footprint as well as broadening their application.

Gul Dolen, a neuroscientist at the Johns Hopkins School of Medicine who studies how the cells and chemicals in animal brains influence animals' social lives, gave ecstasy to octopuses and recorded her observations. The study, published in the journal Current Biology, suggests that the psychoactive drug that can make people feel extra loving toward others also has the same effect on octopuses. An anonymous reader shares the report from The Atlantic: [Dolen] and her colleague Eric Edsinger put five Californian two-spot octopuses individually into the middle of three connected chambers and gave them free rein to explore. One of the adjacent chambers housed a second octopus, confined inside an overturned plastic basket. The other contained an unfamiliar object, such as a plastic flower or a Chewbacca figurine. Dolen and Edsinger measured how long the main animal spent in the company of its peer, and how long with the random toy. The free-moving individuals thoroughly explored the chambers, and from their movements, Dolen realized that individuals of any sex gravitate toward females, but avoid males. Next, she dosed the animals with ecstasy. Again, there's no precedent for this, but researchers often anesthetize octopuses by dunking them in ethanol -- a humane procedure with no lasting side effects. So Dolen and Edsinger submerged their octopuses in an MDMA solution, allowing them to absorb the drug through their gills. At first they used too high a dose, and the animals "freaked out and did all these color changes," Dolen says. But once the team found a more suitable dose, the animals behaved more calmly -- and more sociably. "With ecstasy in their system, the five octopuses spent far more time in the company of the same trapped male they once shunned," the report continues. "Even without a stopwatch, the change was obvious. Before the drug, they explored the chamber with the other octopus very tentatively."

"They mashed themselves against one wall, very slowly extended one arm, touched the [other animal], and went back to the other side," Dolen says. "But when they had MDMA, they had this very relaxed posture. They floated around, they wrapped their arms around the chamber, and they interacted with the other octopus in a much more fluid and generous way. They even exposed their [underside], where their mouth is, which is not something octopuses usually do."

"An experiment has confirmed that quantum mechanics allows events to occur with no definite causal order," reports an article shared by long-time Slashdot readers UpnAtom and jd. Researchers at the University of Queensland in Australia believe this could link Einstein's general theory of relativity to quantum mechanics, according to Physics World: In classical physics -- and everyday life -- there is a strict causal relationship between consecutive events. If a second event (B) happens after a first event (A), for example, then B cannot affect the outcome of A. This relationship, however, breaks down in quantum mechanics because the temporal spread of a particles's wave function can be greater than the separation in time between A and B. This means that the causal order of A and B cannot be always be distinguished by a quantum particle such as a photon.

In their experiment, Romero, Costa and colleagues created a "quantum switch", in which photons can take two paths. One path involves being subjected to operation A before operation B, while in the other path B occurs before A. The order in which the operations are performed is determined by the initial polarization of the photon as it enters the switch.... The team did the experiment using several different types of operation for A and B and in all cases they found that the measured polarization of the output photons was consistent with their being no definite causal order between when A and B was applied. Indeed, the measurements backed indefinite causal order to a whopping statistical significance of 18 -- well beyond the 5 threshold that is considered a discovery in physics.
Science Magazine applauds the experiments for "obliterating our common sense notion of before and after and, potentially, muddying the concept of causality.

An anonymous reader quotes a report from Science Magazine: Frustrated with the slow transition toward open access (OA) in scientific publishing, 11 national funding organizations in Europe turned up the pressure today. As of 2020, the group, which jointly spends about $8.8 billion on research annually, will require every paper it funds to be freely available from the moment of publication. In a statement, the group said it will no longer allow the 6- or 12-month delays that many subscription journals now require before a paper is made OA, and it won't allow publication in so-called hybrid journals, which charge subscriptions but also make individual papers OA for an extra fee. The move means grantees from these 11 funders -- which include the national funding agencies in the United Kingdom, the Netherlands, and France as well as Italy's National Institute for Nuclear Physics -- will have to forgo publishing in thousands of journals, including high-profile ones such as Nature, Science, Cell, and The Lancet, unless those journals change their business model. Not everyone is pleased by the decision. A spokesperson for Springer Nature, which publishes more than 3,000 journals, said the plan "potentially undermines the whole research publishing system." A spokesperson for AAAS, Science's publisher, added: "Implementing such a plan, in our view, would disrupt scholarly communications, be a disservice to researchers, and impinge academic freedom."

schwit1 shares a report from Time: In a new paper published in Science, researchers led by Eric Olson, professor and chair of molecular biology at UT Southwestern Medical Center, reported that he and his team successfully used CRISPR to correct the genetic defect responsible for Duchenne muscular dystrophy in four beagles bred with the disease-causing gene. It's the first use of CRISPR to treat muscular dystrophy in a large animal. (Previous studies had tested the technology on rodents.) In varying degrees, the genetic therapy halted the muscle degradation associated with the disease. Duchenne is caused by mutations in the dystrophin gene, which codes for a protein essential for normal muscle function. People born with the disease are often eventually confined to wheelchairs as their muscles continue to weaken, and in the later stages, many rely on ventilators to breathe as their diaphragm muscles stop working. Eventually, they develop heart and respiratory failure.

Olson and his team "fixed" the mutated dystrophin gene in four dogs by splicing out an offending section of the gene using CRISPR. The gene editing technology, discovered in 2012, can cut out sections of DNA at precise locations (and also potentially introduce new DNA as well). In the case of Duchenne, says Olson, simply snipping out a section of the mutated dystrophin gene allows the gene to make enough of the proper protein that muscles need to function. The hope is that if those animal studies and human trials prove this technique is safe and effective, CRISPR could potentially lead to a cure for Duchenne, Olson says. "We are going for a cure, not a treatment," he says. "All of the other therapies so far for Duchenne muscular dystrophy have treated the symptoms and consequences of the disease. This is going right at the root cause of the genetic mutation."

Packing more energy into batteries is the key to delivering electric cars with longer range, smartphones that can last days -- and cheaper electronic products all around. Lithium-oxygen batteries represent one of the more promising paths toward that end. From a report: They could boost energy density by an order of magnitude above conventional lithium-ion batteries -- in theory, at least. In a paper published this week in Science journal, researchers at the University of Waterloo identified ways of addressing some of the major hurdles to converting that potential into commercial reality.

A critical problem has been that as a lithium-oxygen battery discharges, oxygen is converted into superoxide and then lithium peroxide, reactive compounds that corrode the battery's components over time. That, in turn, limits its recharging ability -- and any real-world utility. To get around the problem, researchers switched from a carbon cathode to one made of nickel oxide and supported by a stainless steel mesh. They also used molten salt for the electrolyte -- the part of the battery that allows positively charged ions to move between the electrodes -- and raised the battery's operating temperature to 150C. Those steps made it possible to achieve about three times the number of charging cycles as earlier lithium-oxygen efforts. The researchers also managed to increase the energy per unit of mass by more than 50 percent.

An anonymous reader quotes a report from The Guardian: The latest study provides new evidence that sleep deprivation has a direct influence on basic metabolism and the body's balance between fat and muscle mass. In the study, published in the journal Science Advances, 15 healthy volunteers each attended a testing session on two occasions, once after a normal night's sleep and once after staying up all night. During the visit, they gave samples of fat and muscle tissue and blood. After sleep deprivation, people's fat tissue showed changes in gene activity that are linked to cells increasing their tendency to absorb lipids and also to proliferate.

By contrast, in muscle the scientists saw reduced levels of structural proteins, which are the building blocks the body requires to maintain and build muscle mass. Previous epidemiological studies have also found shift workers and those who sleep less have lower muscle mass. This may be in part down to lifestyle factors, but the latest work shows that there are also fundamental biological mechanisms at play. The study also found an increase in inflammation in the body after sleep deprivation, which is a known risk factor for type 2 diabetes.

An anonymous reader quotes a report from Live Science: Scientists found that death travels in unremitting waves through a cell, moving at a rate of 30 micrometers (one-thousandth of an inch) every minute, they report in a new study published Aug. 10 in the journal Science. That means, for instance, that a nerve cell, whose body can reach a size of 100 micrometers, could take as long as 3 minutes and 20 seconds to die. Apoptosis -- or programmed cell death -- is necessary for clearing our bodies of unnecessary or harmful cells, such as those that are infected by viruses. It also helps shape organs and other features in a developing fetus.

To figure this out, Ferrell and his team observed the process in one of the larger cells present in nature: egg cells of Xenopus laevis, or African clawed frogs. They filled test tubes with fluid from the eggs and triggered apoptosis, which they watched unfold by tagging involved proteins with fluorescent light. If they saw fluorescent light, it meant apoptosis was taking place. They found that the fluorescent light traveled through the test tubes at a constant speed. If apoptosis had carried on due to simple diffusion (the spreading of substances from an area of high concentration to one of low concentration), the process would have slowed down toward the end, according to the study. Since it didn't, the researchers concluded that the process they observed must be "trigger waves," which they likened to "the spread of a fire through a field." The caspases that are first activated, activate other molecules of caspases, which activate yet others, until the entire cell is destroyed.

Five years ago, researchers set out to replicate experiments from 50 high-impact cancer biology papers. Now, due to various challenges relating to a lack of funding and expertise, the project only expects to complete just 18 studies. Science Magazine reports: The Reproducibility Project: Cancer Biology (RP:CP) began in October 2013 as an open effort to test replicability after two drug companies reported they had trouble reproducing many cancer studies. The work was a collaboration with Science Exchange, a company based in Palo Alto, California, that found contract labs to reproduce a few key experiments from each paper. Funding included a $1.3 million grant from the Laura and John Arnold Foundation, enough for about $25,000 per study. Experiments were expected to take 1 year.

Costs rose and delays ensued as organizers realized they needed more information and materials from the original authors; a decision to have the proposed replications peer reviewed also added time. Organizers whittled the list of papers to 37 in late 2015, then to 29 by January 2017. In the past few months, they decided to discontinue 38% or 11 of the ongoing replications, Errington says. (Elizabeth Iorns, president of Science Exchange, says total costs for the 18 completed studies averaged about $60,000, including two high-priced "outliers.") One reason for cutting off some replications was that it was taking too long to troubleshoot or optimize experiments to get meaningful results... So far, the project has published replication results for 10 of the 18 studies. "Five were mostly repeatable, three were inconclusive, and two studies were negative, but the original findings have been confirmed by other labs," reports Science Magazine. "In fact, many of the initial 50 papers have been confirmed by other groups, as some of the RP:CB's critics have pointed out."

Five years ago, researchers set out to replicate experiments from 50 high-impact cancer biology papers. Now, due to various challenges relating to a lack of funding and expertise, the project only expects to complete just 18 studies. Science Magazine reports: The Reproducibility Project: Cancer Biology (RP:CP) began in October 2013 as an open effort to test replicability after two drug companies reported they had trouble reproducing many cancer studies. The work was a collaboration with Science Exchange, a company based in Palo Alto, California, that found contract labs to reproduce a few key experiments from each paper. Funding included a $1.3 million grant from the Laura and John Arnold Foundation, enough for about $25,000 per study. Experiments were expected to take 1 year.

Costs rose and delays ensued as organizers realized they needed more information and materials from the original authors; a decision to have the proposed replications peer reviewed also added time. Organizers whittled the list of papers to 37 in late 2015, then to 29 by January 2017. In the past few months, they decided to discontinue 38% or 11 of the ongoing replications, Errington says. (Elizabeth Iorns, president of Science Exchange, says total costs for the 18 completed studies averaged about $60,000, including two high-priced "outliers.") One reason for cutting off some replications was that it was taking too long to troubleshoot or optimize experiments to get meaningful results... So far, the project has published replication results for 10 of the 18 studies. "Five were mostly repeatable, three were inconclusive, and two studies were negative, but the original findings have been confirmed by other labs," reports Science Magazine. "In fact, many of the initial 50 papers have been confirmed by other groups, as some of the RP:CB's critics have pointed out."

Five years ago, researchers set out to replicate experiments from 50 high-impact cancer biology papers. Now, due to various challenges relating to a lack of funding and expertise, the project only expects to complete just 18 studies. Science Magazine reports: The Reproducibility Project: Cancer Biology (RP:CP) began in October 2013 as an open effort to test replicability after two drug companies reported they had trouble reproducing many cancer studies. The work was a collaboration with Science Exchange, a company based in Palo Alto, California, that found contract labs to reproduce a few key experiments from each paper. Funding included a $1.3 million grant from the Laura and John Arnold Foundation, enough for about $25,000 per study. Experiments were expected to take 1 year.

Costs rose and delays ensued as organizers realized they needed more information and materials from the original authors; a decision to have the proposed replications peer reviewed also added time. Organizers whittled the list of papers to 37 in late 2015, then to 29 by January 2017. In the past few months, they decided to discontinue 38% or 11 of the ongoing replications, Errington says. (Elizabeth Iorns, president of Science Exchange, says total costs for the 18 completed studies averaged about $60,000, including two high-priced "outliers.") One reason for cutting off some replications was that it was taking too long to troubleshoot or optimize experiments to get meaningful results... So far, the project has published replication results for 10 of the 18 studies. "Five were mostly repeatable, three were inconclusive, and two studies were negative, but the original findings have been confirmed by other labs," reports Science Magazine. "In fact, many of the initial 50 papers have been confirmed by other groups, as some of the RP:CB's critics have pointed out."

An anonymous reader quotes a report from Phys.Org: Scientists at the Florida State University-headquartered National High Magnetic Field Laboratory have discovered a behavior in materials called cuprates that suggests they carry current in a way entirely different from conventional metals such as copper. The research, published today in the journal Science, adds new meaning to the materials' moniker, "strange metals." Cuprates are high-temperature superconductors (HTS), meaning they can carry current without any loss of energy at somewhat warmer temperatures than conventional, low-temperature superconductors (LTS). Although scientists understand the physics of LTS, they haven't yet cracked the nut of HTS materials. Exactly how the electrons travel through these materials remains the biggest mystery in the field.

For their research on one specific cuprate, lanthanum strontium copper oxide (LSCO), a team led by MagLab physicist Arkady Shekhter focused on its normal, metallic state -- the state from which superconductivity eventually emerges when the temperature dips low enough. This normal state of cuprates is known as a "strange" or "bad" metal, in part because the electrons don't conduct electricity particularly well. Scientists have studied conventional metals for more than a century and generally agree on how electricity travels through them. They call the units that carry charge through those metals "quasiparticles," which are essentially electrons after factoring in their environment. These quasiparticles act nearly independently of each other as they carry electric charge through a conductor. But does quasiparticle flow also explain how electric current travels in the cuprates? At the National MagLab's Pulsed Field Facility in Los Alamos, New Mexico, Shekhter and his team investigated the question. They put LSCO in a very high magnetic field, applied a current to it, then measured the resistance. The resulting data revealed that the current cannot, in fact, travel via conventional quasiparticles, as it does in copper or doped silicon. The normal metallic state of the cuprate, it appeared, was anything but normal.

Matt Kennedy from New Atlas reports of an all-optical Diffractive Deep Neural Network (D2NN) architecture that uses light diffracted through numerous plates instead of electrons. It was developed by Dr. Aydogan Ozcan and his team of researchers at the Chancellor's Professor of electrical and computer engineering at UCLA. From the report: The setup uses 3D-printed translucent sheets, each with thousands of raised pixels, which deflect light through each panel in order to perform set tasks. By the way, these tasks are performed without the use of any power, except for the input light beam. The UCLA team's all-optical deep neural network -- which looks like the guts of a solid gold car battery -- literally operates at the speed of light, and will find applications in image analysis, feature detection and object classification. Researchers on the team also envisage possibilities for D2NN architectures performing specialized tasks in cameras. Perhaps your next DSLR might identify your subjects on the fly and post the tagged image to your Facebook timeline. For now though, this is a proof of concept, but it shines a light on some unique opportunities for the machine learning industry. The research has been published in the journal Science.

Okian Warrior shares a report from Science Magazine: Hopes for an easier regulatory road for genetic engineering in European agriculture were dashed by the Court of Justice of the European Union. In a closely watched decision, the court ruled that plants created with new gene-editing techniques that don't involve transferring genes between organisms -- such as CRISPR -- must go through the same lengthy approval process as traditional transgenic plants. Many researchers had argued that regulators should take a lighter touch when evaluating products created with the new technologies, but environmental groups and their allies successfully argued that they should be subject to the same EU rules that apply to other genetically modified organisms.

The case focused on crops that have been made resistant to herbicides without transferring genes from other species. The French government had passed a law exempting these new gene-edited crops from regulation under the European Union's directive on genetically modified organisms (GMOs), which requires an assessment of risks to health and the environment, as well as labeling, tracking, and monitoring of the products. Confederation Paysanne, a French union in Bagnolet representing small farms, and eight other groups, sued and charged that the plants modified with gene-editing techniques should be regulated under the GMO directive, because they could cause significant harm. The court decided that gene-editing techniques are covered by the GMO directive because they "alter the genetic material of an organism in a way that does not occur naturally." (The court exempted conventional mutagenesis -- the unnatural use of chemicals or radiation to create mutations for plant breeding -- because it has "a long safety record.") It also said the new gene-editing techniques have risks that could be similar to those of transgenic engineering.

According to two complementary studies, sperm change their cargo as they travel the reproductive tract, which can have consequences on the viability of future offspring. Smithsonian reports: The legacy of a dad's behavior can even live on in his child if his epigenetic elements enter an embryo. For instance, mice born to fathers that experience stress can inherit the behavioral consequences of traumatic memories. Additionally, mouse dads with less-than-desirable diets can pass a wonky metabolism onto their kids. Upasna Sharma and Colin Conine, both working under Oliver Rando, a professor of biochemistry at the University of Massachusetts Medical School, were some of the researchers to report such findings in 2016. In their work, Sharma and Conine noted that, in mice, while immature testicular sperm contain DNA identical to that of mature sperm, immature sperm relay different epigenetic information. It turns out that sperm small RNAs undergo post-testes turnover, picking up intel on the father's physical health (or lack thereof) after they're manufactured, but before they exit the body. However, the exact pit stop at which these additional small RNAs hitch a ride remained unknown.

To solve the mystery, Sharma, who led the first of the two new studies, decided to track the composition of small RNAs within mouse sperm as they fled the testes and cruised through the epididymis. She and her colleagues isolated sperm of several different ages from mice, including those about to emerge from the testes, those entering the early part of the epididymis and those in the late part of the epididymis. Sharma was surprised to find that many small RNAs seemed to be discarded or destroyed upon entering the early epididymis; then, the newly vacated sperm reacquired epigenetic intel that reflected the father's state of being, boasting a full set by the time they left the late epididymis. There was only one possible source for the small RNA reacquisition: the cells of the epididymis -- which meant that cells outside of the sperm were transmitting information into future generations. [...] Colin Conine, who led the second of the two new studies, next tested if using immature sperm would have noticeable effects on the offspring of mice. He and his colleagues extracted sperm from the testes, early epididymis and late epididymis and injected them into eggs. All three types of sperm were able to fertilize eggs. However, when Conine transferred the resulting embryos into mouse surrogates, none derived from early epididymal sperm -- the intermediate stage devoid of most small RNAs -- implanted in the uterus. The least and most mature sperm of the bunch were winners -- but somehow, those in the middle were burning out, even though all their genes were intact. The only other explanation was that the defect was temporary. If this was the case, then perhaps, if fed the right small RNAs, the early epididymal sperm could be rescued.

An anonymous reader quotes a report from Science Magazine: For more than 20 years, a team of astronomers has tracked a single star whipping around the supermassive black hole at the center of our galaxy at up to 25 million kilometers per hour, or 3% of the speed of light. Now, the team says the close encounter has put Albert Einstein's theory of gravity to its most rigorous test yet for massive objects, with the light from the star stretched in a way not prescribed by Newtonian gravity. In a study announced today, the team says it has detected a distinctive indicator of Einstein's general theory of relativity called "gravitational redshift," in which the star's light loses energy because of the black hole's intense gravity. The star, called S2, is unremarkable apart from a highly elliptical orbit that takes it within 20 billion kilometers, or 17 light-hours, of the Milky Way's central black hole -- closer than any other known star. A team led by Reinhard Genzel at the Max Planck Institute for Extraterrestrial Physics (MPE) in Garching, Germany, has been tracking S2 since the 1990s, first with the European Southern Observatory's (ESO's) 3.6-meter New Technology Telescope in Chile's Atacama Desert and later with ESO's Very Large Telescope (VLT), made up of four 8-meter instruments. Ghez's team at UCLA also began to observe the star around the same time with the twin 10-meter Keck telescopes in Hawaii. In a paper published today in Astronomy & Astrophysics, Genzel's group reports seeing the combined action of the relativistic effects, with the black hole's gravity redshifting S2's radial velocity by 200 kilometers per second, a small fraction of its overall speed. The results match closely with the predictions of relativity and are inconsistent with Newtonian gravity.

For decades Mars has teased scientists with whispers of water's presence. Now they have some solid evidence. From a report: The Italian Space Agency announced Wednesday that researchers have detected signs of a large, stable body of liquid water locked away beneath a mile of ice near Mars' south pole. The observations were recorded by the Mars Advanced Radar for Subsurface and Ionosphere Sounding instrument -- Marsis for short. "Marsis was born to make this kind of discovery, and now it has," says Roberto Orosei, a radioastronomer at the National Institute for Astrophysics, who led the investigation. His team's findings, which appear in this week's issue of Science, raise tantalizing questions about the planet's geology -- and its potential for harboring life. CNN elaborates: Between May 2012 and December 2015, MARSIS was used to survey the Planum Australe region, which is in the southern ice cap of Mars. It sent radar pulses through the surface and polar ice caps and measured how the radio waves reflected back to Mars Express. Those pulses reflected 29 sets of radar samples that created a map of drastic change in signal almost a mile below the surface. It stretched about 12.5 miles across and looked very similar to lakes that are found beneath Greenland and Antarctic ice sheets on Earth. The radar reflected the feature's brightness, signaling that it's water. "We interpret this feature as a stable body of liquid water on Mars," the authors wrote in the study.

An anonymous reader quotes a report from IEEE Spectrum: Today, a team of researchers at Stanford, led by materials science and engineering associate professor Alberto Salleo and postdoctoral research fellow Onur Parlak, announced in Science Advances that they've developed a wearable patch that can determine how much cortisol someone is producing in seconds, using sweat drawn from the skin under the patch. [Cortisol, a steroid hormone, goes up when a person is under physical or emotional strain.] The stretchy patch pulls in the sweat through perforations to a reservoir. A membrane on top of the reservoir allows charged ions, like sodium and potassium, to pass through. Cortisol, which has no charge, can't pass, and instead blocks the charged ions. Signals sent from an electrical sensor in the patch can be used to detect these backups and determine how much cortisol is in the sweat.

The prototype cortisol detection patch channels sweat into a reservoir; a membrane selectively lets charged ions through, and the amount of these ions detected can be translated into a reading of cortisol levels in the sweat. Parlak tested the prototype on several runners, and reported that the cortisol levels detected by the wearable sensor patch matched those obtained by running samples of the runners' sweat through an ELISA (enzyme-linked immunosorbent assay) test that takes several hours.

An anonymous reader shares an excerpt from Ars Technica: D-Wave's hardware has always occupied a unique space on the computing landscape. It's a general-purpose computer that relies on quantum mechanical effects to perform calculations. And, while other quantum-computer makers have struggled to put more than a few dozen qubits together, D-Wave's systems have already scaled to more than 2,000 addressable bits. But the D-Wave systems don't perform calculations in the same way and, despite all those bits, haven't clearly demonstrated performance that can outpace even traditional computing hardware. But D-Wave has come out with a research paper in Science that suggests that the system can do interesting things even in its current state. The company's researchers have set it loose modeling a quantum system that closely resembles the bits used in the hardware itself, allowing them to examine quantum phase transitions. While this still isn't cutting-edge performance, it does allow researchers full control over the physical parameters of a relevant quantum system as it undergoes phase changes.

An anonymous reader shares a report: A research team at the University Medical Center Gottingen has created a cochlear implant that uses light to restore auditory responses in deaf gerbils. The study provides a proof-of-concept that combining optical stimulation with genetic manipulation can successfully restore sound perception, and could lead to a new generation of more accurate cochlear implants.

Approximately 360 million people worldwide have hearing impairment. Traditional cochlear implants can partially restore the ability to hear in many of these patients by stimulating ear cells with electrical signals. In such devices, however, the generated current tends to spread around each point of contact, activation of a large population of neurons and limiting the resolution and clarity of sound signals. Christian Wrobel and colleagues tackled this obstacle by designing a light-based cochlear implant. Optical stimulation promises spatially confined activation of neurons in the auditory nerve, potentially yielding spatially precise ear cell stimulation with limited spreading.

An anonymous reader quotes a report from Smithsonian: The science of longevity is surprisingly controversial, mainly because there are so few people of extreme old age -- defined at 110 years or older -- around to study. So researchers look to statistics to try and figure out how long people can live. [Ben Guarino reports via The Washington Post] that in 1825, actuary Benjamin Gompertz put forth the idea that the odds of dying grow exponentially as we age. Further research bears that out. Between the age of 30 and 80, the odds of dying double every 8 years. What happens after that, however, is not completely figured out. According to a controversial study released in 2016, which analyzed data from 40 different countries, the average person could make it to 115 with the right genes and interventions, and a few genetic superstars would be able to make it to 125. But that was it, they argued. There was a wall of mortality that medicine and positive thinking simply cannot overcome.

But not everyone is convinced by that data. That's why for the new paper in the journal Science, researchers looked at the lifespans of 3,836 people in Italy who reached the age of 105 or older between 2009 and 2015, with their ages verified by birth certificates. What they found is that the Gompertz law goes a little haywire around the century mark. According to a press release, a 90 year old woman has a 15 percent chance of dying in the next year, and an estimated six years left to live. At age 95, the chance of dying per year jumps to 24 percent. At the age of 105, the chance of dying makes another leap to 50 percent. But then, surprisingly, it levels off, even past 110. In other words, at least statistically, each year some lucky person could flip the coin of life, and if it comes up heads every time, they could live beyond 115 or 125.

Climate discussions typically center on the need to replace fossil-fuel power plants with technologies like wind turbines and solar panels. But a new paper in Science offers a stark reminder that there are still huge parts of the global energy system where we simply don't have affordable ways of halting greenhouse-gas emissions. MIT Technology Review: Air travel, long-distance transportation and shipping, steel and cement manufacturing, and remaining parts of the power sector account for 27 percent of global emissions from the energy and industrial sectors. And the authors say we need much more research, innovation, and strategic coordination to clean up these sources. "If we're really ambitious about meeting our climate targets, we need to be tackling these hard sectors now," says the paper's lead author, Steven Davis, an earth system scientist at the University of California, Irvine.

An anonymous reader quotes a report from Bloomberg: University of Georgia engineering professor Jenna Jambeck said that indeed, part of the reason China is now refusing to process American and European plastic is that so many people tossed waste into the wrong bin, resulting in a contaminated mix difficult or impossible to recycle. In a paper published last week in Science Advances, she and her colleagues calculated that between now and 2030, 111 million metric tons of potentially recyclable plastic will be diverted from Chinese plants into landfills.

Jambeck said that China used to turn a profit by importing the stuff from American and European recycling bins and turning it into useful material. But as other countries attempted to simplify things for consumers with "single stream" recycling -- think of one big blue bin for paper, plastic, metal and glass -- the material reaching China became too contaminated with nonrecyclable items. The instructions to put everything in one bin seemed appealing but made it much easier to do recycling wrong.

DeepMind, Google's artificial intelligence subsidiary in London, has developed a self-training vision computer that generates 'a full 3D model of a scene from just a handful of 2D snapshots," according to its chief executive. From a report: The system, called the Generative Query Network, can then imagine and render the scene from any angle [Editor's note: the link maybe paywalled; alternative source], said Demis Hassabis. GQN is a general-purpose system with a vast range of potential applications, from robotic vision to virtual reality simulation. Details were published on Thursday in the journal Science. "Remarkably, [the DeepMind scientists] developed a system that relies only on inputs from its own image sensors -- and that learns autonomously and without human supervision," said Matthias Zwicker, a computer scientist at the University of Maryland who was not involved in the research. This is the latest in a series of high-profile DeepMind projects, which are demonstrating a previously unanticipated ability by AI systems to learn by themselves, once their human programmers have set the basic parameters.

A new study published in the journal Science finds honeybees are able to understand the concept of zero numerosity, joining the ranks of dolphins, parrots, and primates. Sci-News.com reports: The study authors set out to test the honeybee on its understanding, marking individual honeybees for easy identification and luring them to a specially-designed testing apparatus. The bees were trained to choose an image with the lowest number of elements in order to receive a reward of sugar solution. For example, the bees learned to choose three elements when presented with three vs. four; or two elements when presented with two vs. three. When the scientists periodically tested the bees with an image that contained no elements versus an image that had one or more, the bees understood that the set of zero was the lower number -- despite never having been exposed to an "empty set."

Scientists say they have found evidence of dunes of frozen methane on Pluto, suggesting that the distant world is more dynamic than previously thought. The research has been published in the journal Science. BBC reports: The findings come from analysis of the startling images sent back by Nasa's New Horizons mission, which flew close to Pluto in July 2015. In their study, the researchers explain how they studied pictures of a plain known as Sputnik Planitia, parts of which are covered with what look like fields of dunes. They are lying close to a range of mountains of water ice 5km high. The scientists conclude that the dunes are 0.4-1km apart and that they are made up of particles of methane ice between 200-300 micrometers in diameter -- roughly the size of grains of sand. "The methane grains could have been lofted into the atmosphere by the melting of surrounding nitrogen ice or blown down from nearby mountains," the researchers write in the journal Science. "Understanding how dunes form under Pluto conditions will help with interpreting similar features found elsewhere in the solar system."

Doctors are now one step closer to deploying sensors that can travel to parts of a patient's body to diagnose hard-to-detect conditions. From a report: Researchers have devised a new way to get a sneak peek into what's going on deep in your digestive system, creating a swallowable sensor that, with the help of engineered bacteria and a tiny electrical circuit, can detect the presence of molecules that might be signs of disease and then beam the results to a smartphone app. The device, which scientists validated in pigs, remains a prototype and needs to be refined before it could be used in people. But the researchers, who reported their work Thursday in the journal Science, combined innovations in synthetic biology and microelectronics to create a modular platform that could be adapted to identify a wide range of molecules. "We want to try to illuminate and provide understanding into areas that are not easily accessible," said Dr. Timothy Lu, a bioengineer at the Massachusetts Institute of Technology and senior author of the paper.

travers_r writes: Superior Court Judge Elihu Berle affirmed last week that all coffee sold in California must come with a warning label stating that chemicals in coffee (acrylamide, a substance created naturally during the brewing process) are known to cause cancer and birth defects or other reproductive harm. But judges, journalists, and environmental advocates fail to recognize the critical difference between probably and certainly, which fuels the inaccurate belief that cancer is mostly caused by things in the environment. From a report at Undark: "IARC is one of the leading scientific bodies in the world, and it is also one of several expert panels on which California relies for scientific opinions in such cases. The IARC has concluded that while there is sufficient evidence to consider acrylamide carcinogenic in experimental animals, there is insufficient evidence for carcinogenicity in humans. Therefore, its overall evaluation is that 'acrylamide is probably carcinogenic to humans.'
[...]
Leading experts, in fact, believe that roughly two-thirds of all cancers are the result of mutations to DNA that are caused by natural bodily processes, not exposure to environmental chemicals. This is quite the opposite of the prevailing belief among the public that most cancers are caused by exogenous substances imposed on us by the products and technologies of the modern world. It's this belief -- this fear -- that prompted voters to pass Proposition 65 in 1986. It was a time when fear of hazardous waste and industrial chemicals was high, when chemophobia -- a blanket fear of anything having to do with the word 'chemicals' -- was being seared into the public's mind."

hackingbear writes from a report via Xinhua: Chinese scientists demonstrated the first two-dimensional quantum walks of single photons in real spatial space, which may provide a powerful platform to boost analog quantum computing. Scientists at Shanghai Jiaotong University reported in a paper published in the journal Science Advances a three-dimensional photonic chip with a scale up to 49x49 nodes, by using a technique called femtosecond direct writing. Universal quantum computers, under develop by IBM, Google, Alibaba and other American and Chinese rivals, are far from being feasible before error correction and full connections between the increasing numbers of qubits could be realized. In contrast, analog quantum computers, or quantum simulators, can be built in a straightforward way to solve practical problems directly without error correction, and potentially be able to beat the computational power of classical computers in the near future.

Paul Voosen, reporting for Science magazine: You can't manage what you don't measure. The adage is especially relevant for climate-warming greenhouse gases, which are crucial to manage -- and challenging to measure. In recent years, though, satellite and aircraft instruments have begun monitoring carbon dioxide and methane remotely, and NASA's Carbon Monitoring System (CMS), a $10-million-a-year research line, has helped stitch together observations of sources and sinks into high-resolution models of the planet's flows of carbon. Now, President Donald Trump's administration has quietly killed the CMS, Science has learned.

The move jeopardizes plans to verify the national emission cuts agreed to in the Paris climate accords, says Kelly Sims Gallagher, director of Tufts University's Center for International Environment and Resource Policy in Medford, Massachusetts. "If you cannot measure emissions reductions, you cannot be confident that countries are adhering to the agreement," she says. Canceling the CMS "is a grave mistake," she adds.

sciencehabit writes from a report via Science Magazine: On April 25, the European Space Agency released a data set gathered by the Gaia satellite containing the motions, and much more, of 1.3 billion stars. Astronomers have immediately sifted the data for fast-moving stars. They are prized as forensic tools: When rewound, their trajectories point back to the violent events that launched them. Last week, one team reported the discovery of three white dwarfs -- the dying embers of sunlike stars -- hurtling through the galaxy at thousands of kilometers per second, perhaps flung out from supernovae explosions. Another group reported more than two dozen fast-moving stars, some apparently kicked out by our galaxy's central black hole. And a third has confirmed that a star blazing through the outskirts of the Milky Way actually hails from another galaxy altogether, the Large Magellanic Cloud. The flood of discoveries has sent astronomers racing to their telescopes to check and classify the swift objects, says Harvard University astronomer James Guillochon. The findings have been reported in the journal Science.

sciencehabit writes from a report via Science Magazine: On April 25, the European Space Agency released a data set gathered by the Gaia satellite containing the motions, and much more, of 1.3 billion stars. Astronomers have immediately sifted the data for fast-moving stars. They are prized as forensic tools: When rewound, their trajectories point back to the violent events that launched them. Last week, one team reported the discovery of three white dwarfs -- the dying embers of sunlike stars -- hurtling through the galaxy at thousands of kilometers per second, perhaps flung out from supernovae explosions. Another group reported more than two dozen fast-moving stars, some apparently kicked out by our galaxy's central black hole. And a third has confirmed that a star blazing through the outskirts of the Milky Way actually hails from another galaxy altogether, the Large Magellanic Cloud. The flood of discoveries has sent astronomers racing to their telescopes to check and classify the swift objects, says Harvard University astronomer James Guillochon. The findings have been reported in the journal Science.

An anonymous reader quotes a report from Ars Technica: Alan Turing is rightly famed for his contributions to computer science. But one of his key concepts -- an autonomous system that can generate complex behavior from a few simple rules -- also has applications in unexpected places, like animal behavior. One area where Turing himself applied the concept is in chemistry, and he published a paper describing how a single chemical reaction could create complex patterns like stripes if certain conditions are met. It took us decades to figure out how to actually implement Turing's ideas about chemistry, but we've managed to create a number of reactions that display the behaviors he described. And now, a team of Chinese researchers has figured out how to use them to make something practical: a highly efficient desalination membrane.

To make this a true Turing-style system, the researchers dissolved a large molecule in water. This had the effect of making the water more viscous, which slowed the diffusion of the activator. In addition, the molecule was chosen so that the activator would stick to it, slowing things down even further. The end result was a system similar to the ones defined over a half-century ago. Imaging of the features show that rather than simply thickening the membrane, the membrane retained the same width in these areas; instead, it bulged out to form the structures. That's critical, as the amount of surface area exposed to a salt solution should influence how much water gets through the membrane. In fact, the researchers confirmed that more water was purified when the new membranes were used (the version with the stripes outperformed the dotted one). Unfortunately, the researchers don't compare this system to commercially available membranes. The report has been published in the journal Science.

Science magazine has interviewed David Eagleman, the scientific adviser for HBO's Westworld. Eagleman, a neuroscientist at Stanford University in Palo Alto, California, spoke with the publication about how much we should fear such an AI uprising. From the story, also spoiler alert for those who have not watched the show: Q: Has anything on the show made you think differently about intelligence?
A: The show forces me to consider what level of intelligence would be required to make us believe that an android is conscious. As humans we're very ready to anthropomorphize anything. Consider the latest episode, in which the androids at the party so easily fool the person into thinking they are humans, simply because they play the piano a certain way, or take off their glasses to wipe them, or give a funny facial expression. Once robots pass the Turing test, we'll probably recognize that we're just not that hard to fool.

Q: Can we make androids behave like humans, but without the selfishness and violence that appears in Westworld and other works of science fiction?
A: I certainly think so. I would hate to be wrong about this, but so much of human behavior has to do with evolutionary constraints. Things like competition for survival and for mating and for eating. This shapes every bit of our psychology. And so androids, not possessing that history, would certainly show up with a very different psychology. It would be more of an acting job -- they wouldn't necessarily have the same kind of emotions as us, if they had them period. And this is tied into the question of whether they would even have any consciousness -- any internal experience -- at all.

An anonymous reader quotes a report from The Guardian: The European Union will ban the world's most widely used insecticides from all fields due to the serious danger they pose to bees. The ban on neonicotinoids, approved by member nations on Friday, is expected to come into force by the end of 2018 and will mean they can only be used in closed greenhouses.

Bees and other insects are vital for global food production as they pollinate three-quarters of all crops. The plummeting numbers of pollinators in recent years has been blamed, in part, on the widespread use of pesticides. The EU banned the use of neonicotinoids on flowering crops that attract bees, such as oil seed rape, in 2013. fBut in February, a major report from the European Union's scientific risk assessors (Efsa) concluded that the high risk to both honeybees and wild bees resulted from any outdoor use, because the pesticides contaminate soil and water. This leads to the pesticides appearing in wildflowers or succeeding crops. A recent study of honey samples revealed global contamination by neonicotinoids. The ban on the three main neonicotinoids has widespread public support, with almost 5 million people signing a petition from campaign group Avaaz.

The National Weather Service is choosing automated launchers over human employees to deploy weather balloons in Alaska. From a report: Last Thursday, just before 3 p.m., things began stirring inside the truck-size box that sat among melting piles of snow at the airport in Fairbanks, Alaska. Inside, software ran checks on instruments to measure atmospheric temperature, humidity, and pressure; a tray slid into place; and a nozzle began filling a large balloon with gas. Finally, the roof of the box yawned open and a weather balloon took off into the sunny afternoon, instruments dangling. The entire launch was triggered with the touch of a button, 5 kilometers away at an office of the National Weather Service (NWS).

The flight was smooth, just one of hundreds of twice-daily balloon launches around the world that radio back crucial data for weather forecasts. But most of those balloons are launched by people; the robotic launchers, which are rolling out across Alaska, are proving to be controversial. NWS says the autolaunchers will save money and free up staff to work on more pressing matters. But representatives of the employee union question their reliability, and say they will hasten the end of Alaska's remote weather offices, where forecasting duties and hours have already been slashed. "The autolauncher is just another nail in their coffin," says Kimberly Vaughan, a union steward in Juneau.

Once deployed across the state, the $1.2 million machines, built by Finnish company Vaisala, will save about 8 hours of forecaster time a day -- and about $1 million a year at NWS, Susan Buchanan, an NWS spokesperson says.

An anonymous reader quotes a report from The Guardian: The cow could be left as the biggest land mammal on Earth in a few centuries, according to a new study that examines the extinction of large mammals as humans spread around the world. The spread of hominims -- early humans and related species such as Neanderthals -- from Africa thousands of years ago coincided with the extinction of megafauna such as the mammoth, the sabre-toothed tiger and the glyptodon, an armadillo-like creature the size of a car. "There is a very clear pattern of size-biased extinction that follows the migration of hominims out of Africa," the study's lead author, Felisa Smith, of the University of New Mexico, said of the study published in the journal Science on Thursday. Humans apparently targeted big species for meat, while smaller creatures such as rodents escaped, according the report, which examined trends over 125,000 years. In North America, for instance, the mean body mass of land-based mammals has shrunk to 7.6kg (17lb) from 98kg after humans arrived. If the trend continues "the largest mammal on Earth in a few hundred years may well be a domestic cow at about 900kg", the researchers wrote. That would mean the loss of elephants, giraffes and hippos. In March, the world's last male northern white rhino died in Kenya.

sciencehabit shares a report from Science Magazine: Although artificial intelligence systems may be able to beat humans at board games, we still have the upper hand when it comes to complicated manual tasks. But now, scientists have created robots that can do something even most humans struggle with: assemble an IKEA chair. Putting together a chair requires a combination of complex movements that, in turn, depends on such skills as vision, limb coordination, and the ability to control force. Until now, that was too much to ask of even a sophisticated robot. But researchers have finally broken the dexterity barrier by combining commercially available hardware, including 3D cameras and force sensors, to build two chair-building bots. To construct their IKEA masterpiece, the robots first took pictures to identify each part of the chair. An algorithm planned the motions the robots needed to manipulate the objects without causing any collisions; two robotic arms then performed those actions in concert. Feedback from force sensors also helped: When the robot needed to insert a pin into a hole, for example, it would slide the pin over the surface until it felt a change in force. The robots were able to put together the chair in a little over 20 minutes, which includes the 11 minutes and 21 seconds of planning time and 8 minutes and 55 seconds of actual assembly. The findings have been reported today in Science Robotics.

sciencehabit shares a report from Science Magazine: Although artificial intelligence systems may be able to beat humans at board games, we still have the upper hand when it comes to complicated manual tasks. But now, scientists have created robots that can do something even most humans struggle with: assemble an IKEA chair. Putting together a chair requires a combination of complex movements that, in turn, depends on such skills as vision, limb coordination, and the ability to control force. Until now, that was too much to ask of even a sophisticated robot. But researchers have finally broken the dexterity barrier by combining commercially available hardware, including 3D cameras and force sensors, to build two chair-building bots. To construct their IKEA masterpiece, the robots first took pictures to identify each part of the chair. An algorithm planned the motions the robots needed to manipulate the objects without causing any collisions; two robotic arms then performed those actions in concert. Feedback from force sensors also helped: When the robot needed to insert a pin into a hole, for example, it would slide the pin over the surface until it felt a change in force. The robots were able to put together the chair in a little over 20 minutes, which includes the 11 minutes and 21 seconds of planning time and 8 minutes and 55 seconds of actual assembly. The findings have been reported today in Science Robotics.

An anonymous reader shares a report: A new algorithm creates 3D models using standard video footage from one angle. The system has three stages. First, it analyzes a video a few seconds long of someone moving -- preferably turning 360-degree to show all sides -- and for each frame creates a silhouette separating the person from the background. Based on machine learning techniques -- in which computers learn a task from many examples -- it roughly estimates the 3D body shape and location of joints. In the second stage, it "unposes" the virtual human created from each frame, making them all stand with arms out in a T shape, and combines information about the T-posed people into one, more accurate model. Finally, in the third stage, it applies color and texture to the model based on recorded hair, clothing, and skin.

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.

An anonymous reader quotes a report from Gizmodo: Prosthetic hands have gotten increasingly sophisticated. Many can recreate the complex shape and detail of joints and fingers, while powered prostheses allow for independent, willful movement. But a new study published Wednesday in Science Translational Medicine offers a potential glimpse into the future of the technology: Artificial hands that actually feel like a living limb as they move. The researchers recruited people with amputations who had been given surgery that reconfigured certain muscle and sensory nerves surrounding the amputated limb, allowing them to control their prosthesis through intuitive brain signals (thoughts) sent to the repurposed nerves. Across a series of experiments involving three of these patients, the researchers attached devices that generated vibrations along specific muscles near the amputation site. When the device was turned on, these vibrations created an illusionary sense of kinesthesia -- an awareness of conscious self-movement -- in the prosthetic hand as the person performed tasks with it, both in a virtual stimulation and in the real world. The volunteers had amputations that extended just past their elbow as well as their whole arm. Not only did the experiment let them "feel" their hand as they opened and closed it, but the restored intuition allowed them to perform tasks without needing to constantly look at their hand. And coupled with vision, it gave them overall better motor control over their prosthesis.

sciencehabit writes: Small pockets of water exist deep beneath Earth's surface, according to an analysis of diamonds belched from hundreds of kilometers within our planet. The work, which also identifies a weird form of crystallized water known as ice VII, suggests that material may circulate more freely at some depths within Earth than previously thought. Geophysical models of that flow, which ultimately influences the frequency of earthquakes driven by the scraping of tectonic plates at Earth's surface, may need to be substantially tweaked, scientists say. Such models also help scientists estimate the long-term rates of heat flow through Earth's surface and into space.

An anonymous reader writes: San Francisco Bay Area residents have long been aware of the threat that sea level rise poses to their coastal existence -- but things suddenly look a lot more serious. A new study examines the simultaneous phenomena of rising sea levels and subsiding coastal land, and as Wired reports, the situation is pretty dire. Models that factor in just sea level rise predict that at least 20 square miles could be underwater by 2100. Once you add in subsiding land, that jumps to nearly 50 square miles, and could get as bad as 165 square miles. Or, put another way, by the end of the century, half of the runways and taxiways at San Francisco Airport could be submerged.

The study found that most of the Bay's coastline is sinking at a rate of less than 2 millimeters a year -- and while that may not sound like a lot, the millimeters can add up fast. "You talk to someone about, 'Oh the land is going down a millimeter a year,' and that can be kind of unimpressive," says William Hammond, a researcher at the University of Nevada Reno who studies subsidence (but was not involved in this particular project). "But we know as scientists that these motions, especially if they come from plate tectonics, that they are relentless and they will never stop, at least as long as we're alive on this planet."

A new study shows that people are the prime culprits when it comes to the propagation of misinformation through social networks. Tweets containing falsehoods reach 1,500 people on Twitter six times faster than truthful tweets, the research reveals. Science Magazine reports: The lead author -- Soroush Vosoughi, a data scientist at the Massachusetts Institute of Technology in Cambridge -- and his colleagues collected 12 years of data from Twitter, starting from the social media platform's inception in 2006. Then they pulled out tweets related to news that had been investigated by six independent fact-checking organizations -- websites like PolitiFact, Snopes, and FactCheck.org. They ended up with a data set of 126,000 news items that were shared 4.5 million times by 3 million people, which they then used to compare the spread of news that had been verified as true with the spread of stories shown to be false. They found that whereas the truth rarely reached more than 1000 Twitter users, the most pernicious false news stories routinely reached well over 10,000 people. False news propagated faster and wider for all forms of news -- but the problem was particularly evident for political news, the team reports today in Science. At first the researchers thought that bots might be responsible, so they used sophisticated bot-detection technology to remove social media shares generated by bots. But the results didn't change: False news still spread at roughly the same rate and to the same number of people. By default, that meant that human beings were responsible for the virality of false news.

A new study shows that people are the prime culprits when it comes to the propagation of misinformation through social networks. Tweets containing falsehoods reach 1,500 people on Twitter six times faster than truthful tweets, the research reveals. Science Magazine reports: The lead author -- Soroush Vosoughi, a data scientist at the Massachusetts Institute of Technology in Cambridge -- and his colleagues collected 12 years of data from Twitter, starting from the social media platform's inception in 2006. Then they pulled out tweets related to news that had been investigated by six independent fact-checking organizations -- websites like PolitiFact, Snopes, and FactCheck.org. They ended up with a data set of 126,000 news items that were shared 4.5 million times by 3 million people, which they then used to compare the spread of news that had been verified as true with the spread of stories shown to be false. They found that whereas the truth rarely reached more than 1000 Twitter users, the most pernicious false news stories routinely reached well over 10,000 people. False news propagated faster and wider for all forms of news -- but the problem was particularly evident for political news, the team reports today in Science. At first the researchers thought that bots might be responsible, so they used sophisticated bot-detection technology to remove social media shares generated by bots. But the results didn't change: False news still spread at roughly the same rate and to the same number of people. By default, that meant that human beings were responsible for the virality of false news.

Researchers find fake news reaches users up to 20 times faster than factual content -- and real users are more likely to spread it than bots. From a report: "Falsehood flies, and the truth comes limping after it," wrote Jonathan Swift in 1710. Now a group of scientists say they have found evidence Swift was right -- at least when it comes to Twitter. In the paper, published in the journal Science, three MIT researchers describe an analysis of a vast amount of Twitter data: more than 125,000 stories, tweeted more than 4.5 million times in total, all categorised as being true or false by at least one of six independent fact-checking organisations. The findings make for unhappy reading. "Falsehood diffused significantly farther, faster, deeper and more broadly than the truth in all categories of information," they write, "and the effects were more pronounced for false political news than for false news about terrorism, natural disasters, science, urban legends or financial information."

How much further? "Whereas the truth rarely diffused to more than 1,000 people, the top 1% of false-news cascades routinely diffused to between 1,000 and 100,000 people," they write. In other words, true facts don't get retweeted, while too-good-to-be-true claims are viral gold. How much faster? "It took the truth about six times as long as falsehood to reach 1,500 people, and 20 times as long as falsehood to reach a cascade depth of 10" -- meaning that it was retweeted 10 times sequentially (so, for example, B reads A's feed and retweets a tweet, and C then reads B's feed and retweets the same tweet, all the way to J).

The booming field of artificial intelligence (AI) is grappling with a replication crisis, much like the ones that have afflicted psychology, medicine, and other fields over the past decade. From a report: AI researchers have found it difficult to reproduce many key results, and that is leading to a new conscientiousness about research methods and publication protocols. "I think people outside the field might assume that because we have code, reproducibility is kind of guaranteed," says Nicolas Rougier, a computational neuroscientist at France's National Institute for Research in Computer Science and Automation in Bordeaux. "Far from it." Last week, at a meeting of the Association for the Advancement of Artificial Intelligence (AAAI) in New Orleans, Louisiana, reproducibility was on the agenda, with some teams diagnosing the problem -- and one laying out tools to mitigate it.

An anonymous reader quotes a report from The Guardian: Household cleaners, paints and perfumes have become substantial sources of urban air pollution as strict controls on vehicles have reduced road traffic emissions, scientists say. Researchers in the US looked at levels of synthetic "volatile organic compounds", or VOCs, in roadside air in Los Angeles and found that as much came from industrial and household products refined from petroleum as from vehicle exhaust pipes. The compounds are an important contributor to air pollution because when they waft into the atmosphere, they react with other chemicals to produce harmful ozone or fine particulate matter known as PM2.5. Ground level ozone can trigger breathing problems by making the airways constrict, while fine airborne particles drive heart and lung disease. Writing in the journal Science, De Gouw and others report that the amount of VOCs emitted from household and industrial products is two to three times higher than official US estimates suggest. The result is surprising since only about 5% of raw oil is turned into chemicals for consumer products, with 95% ending up as fuel.