NASA

NASA's Cassini Probe Begins Its 'Grand Finale' Through Saturn's Atmosphere (space.com) 33

An anonymous reader quotes Space.com: After orbiting Saturn for more than 13 years, NASA's Cassini spacecraft is getting ready to say goodbye. On Monday (August 14), Cassini made the first of five passes through Saturn's upper atmosphere, kicking off the last phase of the mission's "Grand Finale." After completing those five dives, Cassini will come back around again one last time, plunging into Saturn's atmosphere on September 15. This will be a suicide maneuver: Cassini will burn up in the ringed planet's thick air, turning into a meteor in the Saturn sky...

Cassini's radar will be able to look into the atmosphere and see features as small as 16 miles (25 km) wide, about 100 times smaller than what it could see from its usual orbital positions. The Grand Finale will include one final swing by Saturn's largest moon, Titan, on Sept. 11. Titan's gravity will slow Cassini's orbit around Saturn and bend its path to send the spacecraft toward its September 15 encounter with the planet... Cassini will keep sending back data on September 15 until it gets to an altitude where atmospheric density is about twice what it encountered during its final five passes, NASA officials said. At that point, mission controllers will lose contact with the probe because its thrusters won't be able to keep Cassini's antenna pointed toward Earth; there will simply be too much air to push against.

The second dip happens this weekend, and NASA has created a special web page tracking Cassini's current location for its final 28 days.
Communications

Atlas 5 Rocket Launches $400 Million NASA Satellite Into Space (spaceflightnow.com) 48

A new communications hub has been successfully deployed in space today thanks to the United Launch Alliance Atlas 5 rocket. "TDRS is a critical national asset have because of its importance to the space station and all of our science missions, primarily the Hubble Space Telescope and Earth science missions that use TDRS," said Tim Dunn, NASA's TDRS-M launch director. Spaceflight Now reports: With its main engine running at full throttle, the Atlas 5 booster lifted off at 8:29 a.m. EDT (1229 GMT) from Complex 41 at Cape Canaveral. The 191-foot-tall rocket, generating 860,000 pounds of thrust, aimed eastward and accelerated out of the atmosphere with NASA's TDRS-M spacecraft. Within just five minutes, the rocket had shed 92 percent of its liftoff weight and transitioned to the high-energy Centaur upper stage. An elliptical parking orbit was achieved within 18 minutes of takeoff, beginning a 90-minute quiescent coast higher through space to reach the optimum conditions for the second burn by Centaur. That minute-long boost over the Indian Ocean propelled the 7,610-pound payload into a customized high-perigee geosynchronous transfer orbit. The spacecraft was deployed by the launcher at T+plus 1 hour, 53 minutes to cheers and handshakes all around.

The $408 million TDRS-M was built and launched with the sole purpose to extend the useful life of NASA's constant communications infrastructure, supporting the astronauts around-the-clock aboard the International Space Station, supplying contact with the Hubble Space Telescope and transmitting the data from almost 40 science spacecraft studying Earth's environment and space.

Medicine

Memories of Fear Could Be Permanently Erased, Study Shows (theguardian.com) 37

A new study unpicks why certain sounds can stir alarming memories, and reveals a new approach to wiping such memories from the brain. The Guardian reports: Published in the journal Neuron by Cho and his colleague Woong Bin Kim, the research reveals how the team used genetically modified mice to examine the pathways between the area of the brain involved in processing a particular sound and the area involved in emotional memories, known as the amygdala. In the first part of the experiment the team played both a high pitched and low-pitched tone to mice. But, when the high-pitched sound was played, the researchers also gave the mice a small electric shock to their feet. When the high-pitched tone was subsequently played on its own, the mice froze in fear; no such response was seen when the alternative, low-pitched, tone was played. The team then looked to see if there were differences between the high-pitch and low-pitch tone pathways in the brains of the mice, revealing that, among the mice exposed electric shocks, the connections within the "high-pitched" pathway had become stronger, while the other pathway remained unchanged. The team found that when mice were subsequently repeatedly exposed to high-pitched sounds without the shocks they lost their fear -- a process known as fear extinction.

But the team discovered that using a technique called optogenetics, it was possible to truly erase the unpleasant memories. This technique involved the researchers using a virus to introduce genes into particular neurons in the brains of the mice that were involved in the "high-pitch" pathways. Once inside the cells, the genes result in the production of proteins which respond to light, allowing researchers to control the activity of the neurons. Taking mice with the fearful memories, the team exposed the neurons involved in the "high-pitch" pathway to low-frequency light -- an approach which weakens the connections between the neurons. The upshot was that the mice no longer appeared fearful when they heard the high-pitched tone.

Science

Self-sufficient Eclipse Chasers Hit the Road To 'Totality' (reuters.com) 40

An anonymous reader shares a report: Michael Zeiler packed his portable toilet then headed out on a 10-hour drive from New Mexico to Wyoming where, on Monday, he intends to mark the ninth time he has seen the moon pass in front of the sun in a total solar eclipse. Zeiler is a self-described "eclipse chaser," part of a group of avid astronomy buffs, telescope hobbyists and amateur photographers whose passion for such celestial events takes them to the far corners of the earth. For the first coast-to-coast total solar eclipse in the United States in almost a century, and the first visible anywhere in the Lower 48 states since 1979, Zeiler had only to drive some 650 miles (1,046 km) from the desert Southwest to the Rockies. He showed up prepared and early on Wednesday at his destination in Casper, Wyoming, within the "path of totality," the corridor over which the moon's 70-mile-wide shadow will be cast as it crosses the United States over 93 minutes. Along that path at the height of the eclipse on Aug. 21, the sun will be completely blotted out except for its outer atmosphere, known as the corona.
Medicine

New Immunotherapy Trial Cures Kids of Peanut Allergy For Up To Four Years (theguardian.com) 160

Using a new kind of immunotherapy treatment, Australian researchers have managed to cure a majority of the children in their study suffering from a peanut allergy. "The desensitization to peanuts persisted for up to four years after treatment," reports The Guardian. From the report: Tang, an immunologist and allergist, pioneered a new form of treatment that combines a probiotic with peanut oral immunotherapy, known as PPOIT. Instead of avoiding the allergen, the treatment is designed to reprogram the immune system's response to peanuts and eventually develop a tolerance. It's thought that combining the probiotic with the immunotherapy gives the immune system the "nudge" it needs to do this, according to Tang. Forty-eight children were enrolled in the PPOIT trial and were randomly given either a combination of the probiotic Lactobacillus rhamnosus with peanut protein in increasing amounts, or a placebo, once daily for 18 months. At the end of the original trial in 2013, 82% of children who received the immunotherapy treatment were deemed tolerant to peanuts compared with just 4% in the placebo group. Four years later, the majority of the children who gained initial tolerance were still eating peanuts as part of their normal diet and 70% passed a further challenge test to confirm long-term tolerance. The results have been published in the Lancet Child & Adolescent Health.
Earth

The Health Benefits of Wind and Solar Exceed the Cost of All Subsidies (arstechnica.com) 422

New submitter TheCoroner writes: A paper in Nature Energy suggests that the benefits we receive from moving to renewables like wind and solar that reduce air pollution exceed the cost of the subsidies required to make them competitive with traditional fossil fuels. Ars Technica reports: "Berkeley environmental engineer Dev Millstein and his colleagues estimate that between 3,000 and 12,700 premature deaths have been averted because of air quality benefits over the last decade or so, creating a total economic benefit between $30 billion and $113 billion. The benefits from wind work out to be more than 7 cents per kilowatt-hour, which is more than unsubsidized wind energy generally costs.

This study ambitiously tries to estimate the benefits from emissions that were avoided because of the increase in wind and solar energy from 2007 through 2015, and to do so for the whole of the U.S. Millstein and colleagues looked at carbon emissions, as well as sulphur dioxides, nitrogen oxides, and particulate matter, all of which contribute to poor air quality. There are other factors that also need to be considered. A rise in renewables isn't the only thing that has been changing in the energy sector: fuel costs and regulation have also played a role. How much of the benefit can be attributed to wind and solar power, and how much to other changes? The researchers used models that track the benefits attributable to renewable power as a proportion of the total reduction in emissions.

Science

Dilution of Whisky -- the Molecular Perspective (nature.com) 82

From a new published paper in Scientific Report by Bjorn C. G. Karlsson and Ran Friedman: Despite the growing knowledge of the nature of water-alcohol mixtures on a molecular level, much less is known on the interaction of water, alcohol and small solutes. In particular, the nature of the interaction between the solvent and taste-carrying molecules, such as guaiacol, is not known. To address this gap, we used MD simulations to study the distribution of guaiacol in water-alcohol mixtures of different concentrations. Our simulations revealed that guaiacol is present at the air-liquid interface at ethanol concentrations that correspond to the alcohol content of bottled or diluted whiskies. Because the drink is consumed at the interface first, our findings help to understand why adding water to whisky helps to enhance its taste. A molecular understanding of the nature of taste compounds in water-alcohol mixtures allows for optimizing the taste of alcoholic spirits. [...] Overall, there is a fine balance between diluting the whisky to taste and diluting the whisky to waste.
Google

Google Lunar X-Prize Extends Deadline Through March 2018 (space.com) 30

schwit1 writes: The Google Lunar X-Prize has announced that it has extended its contest deadline from the end of 2017 to the end of March 2018 for the finalists to complete their lunar rover mission and win the grand prize of $30 million. They also announced several additional consolation prizes that all of the remaining five contestants can win should they achieve lunar orbit ($1.75 million) or successfully achieve a soft landing ($3 million), even if they are not the first to do it. At least one team, Moon Express, will be helped enormously by the extra three months. This gives Rocket Lab just a little extra time to test its rocket before launching Moon Express's rover to the Moon.
United Kingdom

Deadly Drug-Resistant Fungus Sparks Outbreaks In UK (arstechnica.com) 146

An anonymous reader quotes a report from Ars Technica: More than 200 patients in more than 55 UK hospitals were discovered by healthcare workers to be infected or colonized by the multi-drug resistant fungus Candida auris, a globally emerging yeast pathogen that has experts nervous. Three of the hospitals experienced large outbreaks, which as of Monday were all declared officially over by health authorities there. No deaths have been reported since the fungus was first detected in the country in 2013, but 27 affected patients have developed blood infections, which can be life-threatening. And about a quarter of the more than 200 cases were clinical infections. Officials in the UK aimed to assuage fear of the fungus and assure patients that hospitals were safe. "Our enhanced surveillance shows a low risk to patients in healthcare settings. Most cases detected have not shown symptoms or developed an infection as a result of the fungus," Dr Colin Brown, of Public Health England's national infection service, told the BBC.

Yet, public health experts are uneasy about the rapid emergence and level of drug resistance the pathogen is showing. In a surveillance update in July, the U.S. Centers for Disease Control and Prevention said that C. auris "presents a serious global health threat." It was first identified in the ear of a patient in Japan in 2009. Since then, it has spread swiftly, showing up in more than a dozen countries, including the U.S., according to the CDC. So far, health officials have reported around 100 infections in nine U.S. states and more than 100 other cases where the fungus was detected but wasn't causing an infection.

Power

Australian Scientists Figure Out How Zinc-Air Batteries Can Replace Lithium-Ion Batteries (gizmodo.com.au) 117

Researchers at the University of Sydney has figured out how to solve one of the biggest problems standing in the way for zinc-air batteries to replace lithium-ion batteries. The reason zinc batteries are so sought after is because they're powered by zinc metal -- the 24th most abundant element in Earth's crust. Not only are they cheaper to produce than lithium-ion batteries, they can theoretically store five times more energy, are much safer and environmentally friendly. The problem with zinc batteries stems around them being difficult to charge because of the lack of electrocatalysts needed to reduce and generate oxygen during the discharging and charging of a battery. labnet shares a report from Gizmodo: "Up until now, rechargeable zinc-air batteries have been made with expensive precious metal catalysts, such as platinum and iridium oxide. In contrast, our method produces a family of new high-performance and low-cost catalysts." These new catalysts are produced through the simultaneous control of the composition, size and crystallinity of metal oxides of earth-abundant elements like iron, cobalt and nickel. They can then be applied to build rechargeable zinc-air batteries. Researcher Dr Li Wei, also from the University's Faculty of Engineering and Information Technologies, said trials of zinc-air batteries developed with the new catalysts had demonstrated "excellent rechargeability" -- including less than a 10 percent battery efficacy drop over 60 discharging/charging cycles of 120 hours. The research was published in the journal Advanced Materials.
Science

Tiny Robots Crawl Through Mouse's Stomach To Release Antibiotics (newscientist.com) 15

Tiny robotic drug deliveries could soon be treating diseases inside your body. For the first time, micromotors -- autonomous vehicles the width of a human hair -- have cured bacterial infections in the stomachs of mice, using bubbles to power the transport of antibiotics. From a report: "The movement itself improves the retention of antibiotics on the stomach lining where the bacteria are concentrated," says Joseph Wang at the University of California San Diego, who led the research with Liangfang Zhang. In mice with bacterial stomach infections, the team used the micromotors to administer a dose of antibiotics daily for five days. At the end of the treatment, they found their approach was more effective than regular doses of medicine. The tiny vehicles consist of a spherical magnesium core coated with several different layers that offer protection, treatment, and the ability to stick to stomach walls. After they are swallowed, the magnesium cores react with gastric acid to produce a stream of hydrogen bubbles that propel the motors around. This process briefly reduces acidity in the stomach. The antibiotic layer of the micromotor is sensitive to the surrounding acidity, and when this is lowered, the antibiotics are released.
Medicine

Energy Drinks May Trigger Future Substance Use, Says Study (medscape.com) 232

New research suggests persistent consumption of energy drinks may predispose young adults to substance use. "Investigators, led by Amelia M. Arria, PhD, School of Public Health, University of Maryland, College Park, found that college students who regularly drink highly caffeinated energy drinks were at increased risk for later use of alcohol, cocaine, or prescription stimulants," reports Medscape. From the report: The research included students enrolled in an ongoing longitudinal study that began in 2004 at a large public university. The analysis included 1099 participants (54% women; 72% non-Hispanic white) who completed at least one annual assessment in which patterns of energy drink consumption were assessed. In interviews, participants were asked which energy drinks they had consumed, and how often, in the past year. They were categorized into three patterns of use: Frequent (52 or more days); Occasional (12 - 51 days); Infrequent (1 - 11 days). The investigators found that sensation seeking, conduct problems, and behavioral dysregulation were all positively associated with a higher probability of energy drink consumption, with the nonuse group having the lowest and the persistent group the highest risk scores. The study was published in the journal Drug and Alcohol Dependence.
Medicine

Scientists Finally Unlock the Recipe For Magic Mushrooms (gizmodo.com) 131

An anonymous reader writes: Aside from being a schedule 1 drug, scientists haven't fully understood the chemistry behind how mushrooms produce the chemical psilocybin -- until now. A new study may finally lay the groundwork for a medical-grade psilocybin patients can take. Gizmodo reports: "Living things make molecules through a series of chemical reactions, similar to how car makers produce cars on assembly lines. Enzymes act as the workers/robots, speeding up the reactions by helping put the pieces together. Actually making psilocybin requires mapping the biological factory. A 1968 paper (obviously it was in 1968) offered a proposed order of events leading to a finished psilocybin molecule, by adding radioactive elements and watching what happened to them on the assembly line. The researchers thought that maybe tryptophan, the amino acid everyone wrongly says makes you sleepy, was the first piece, which then went through four successive steps to become the finished product. The new study shows that the 1968 paper got the order wrong, and introduces the responsible genes and enzymes, the workers that do the specific task to get the final product. This time around, mapping the factory required sequencing the genomes of two magic mushroom species, Psilocybe cubensis and Psilocybe cyanescens. Then, the researchers found exactly which genes produce the required enzymes and spliced them into E. coli bacteria. Using those enzymes, they were able to rebuild the factory and create their own psilocybin." The study has been published in the German journal Angewandte Chemie.
Medicine

Plants 'Hijacked' To Make Polio Vaccine (bbc.com) 59

Plants have been "hijacked" to make polio vaccine in a breakthrough with the potential to transform vaccine manufacture, say scientists. From a report: The team at the John Innes Centre, in Norfolk, says the process is cheap, easy and quick. As well as helping eliminate polio, the scientists believe their approach could help the world react to unexpected threats such as Zika virus or Ebola. Experts said the achievement was both impressive and important. The vaccine is an "authentic mimic" of poliovirus called a virus-like particle. Outwardly it looks almost identical to poliovirus but -- like the difference between a mannequin and person -- it is empty on the inside. It has all the features needed to train the immune system, but none of the weapons to cause an infection.

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