hooligun shares a report from Phys.Org: To kill bacteria in the blood, our immune system relies on nanomachines that can open deadly holes in their targets. UCL scientists have now filmed these nanomachines in action, discovering a key bottleneck in the process which helps to protect our own cells. [...] For this study, the researchers mimicked how these deadly holes are formed by the membrane attack complex (MAC) using a model bacterial surface. By tracking each step of the process, they found that shortly after each hole started to form, the process stalled, offering a reprieve for the body's own cells. The team say the process pauses as 18 copies of the same protein are needed to complete a hole. Initially, there's only one copy which inserts into the bacterial surface, after which the other copies of the protein slot into place much more rapidly.

To film the immune system in action at nanometer resolution and at a few seconds per frame, the scientists used atomic force microscopy. This type of microscopy uses an ultrafine needle to feel rather than see molecules on a surface, similar to a blind person reading Braille. The needle repeatedly scans the surface to produce an image that refreshes fast enough to track how immune proteins get together and cut into the bacterial surface. The study has been published in the journal Nature Communications.

Researchers at the University of Washington have discovered that some microbes in the Pacific Ocean actively breath arsenic. "The discovery has implications for how life may adapt to a changing climate, as well as where we might find it on other planets," reports New Atlas. From the report: The discovery was made in water samples gathered in the Pacific Ocean off the coast of Mexico. After conducting genetic analyses on DNA from those samples, the team found two genetic pathways that are known to help organisms gain energy by converting one form of arsenic molecule into another, and back again. Arsenic-breathing microbes have previously been found in hot springs or lakes with high arsenic levels, but finding them in the ocean, where there isn't all that much arsenic to begin with, is quite strange.

"We've known for a long time that there are very low levels of arsenic in the ocean," says Gabrielle Rocap, co-author of the study. "But the idea that organisms could be using arsenic to make a living -- it's a whole new metabolism for the open ocean." That said, it does seem to be a very small population -- less than one percent of the microbes in these waters. They appear to be distantly related to the other arsenic-respiring species on land and in lakes, which may suggest that this survival strategy is a holdover from an ancient time, when the levels of arsenic were naturally much higher. The study has been published in the journal Proceedings of the National Academy of Sciences.

The International Space Station tweeted Sunday that a SpaceX Dragon cargo craft was expected to arrive early Monday morning. "Get up early and catch live coverage of the rendezvous and capture on nasa.gov/live beginning at 5:30 a.m. EDT."

But Teslarati reports that there's also good news about its booster rocket: SpaceX has safely returned Falcon 9 booster B1056 to port and lifted the rocket ashore after successfully supporting Cargo Dragon's 18th mission to the International Space Station. B1056's safe return is by no means a surprise, but it is still a relief after mild issues caused Falcon Heavy center core B1055 to topple over just a few weeks prior. SpaceX's robotic "Octagrabber" was visibly attached to newest Falcon 9 booster, taking advantage of compatibility not available to the Falcon Heavy core. According to NASA and SpaceX, the booster's recovery was weighing on the minds of both stakeholders thanks to interest in reusing B1056 on future Cargo Dragon launches....

SpaceX VP of Flight Reliability Hans Koenigsmann noted that SpaceX is moving to a concept of operations where booster recovery is just as important and just as necessary as any other technical aspect of launch. In other words, when SpaceX drone ship Of Course I Still Love You suffered a rare hardware failure that hobbled its redundant power supplies, NASA had no qualms with the company's decision to scrub the launch attempt. In fact, confirming educated speculation previously published on Teslarati, NASA had a "vested interest" in the successful recovery of B1056. According to NASA ISS manager Kenny Todd's comments, NASA unequivocally wants SpaceX to fly its next Cargo Dragon mission -- CRS-18, NET mid-July -- on the newly flight-proven booster. NASA is even open to flying on B1056 for a third time on CRS-19, pending the condition and availability of the booster.

Unique in SpaceX's Falcon 9 Block 5 fleet thanks to an exceptionally gentle reentry and recovery, B1056 should easily lend itself to multiple reuses in support of future NASA missions. In fact, of the three (up to as many as five) additional CRS1 Cargo Dragon missions still on contract, there is no immediate technical reason to assume that Falcon 9 B1056 can't be involved in a majority of those launches, if not all of them. NASA, of course, has the final say in which Falcon 9s their missions launch on, but the agency's apparent openness to launching on a twice-flown booster opens the door for thrice-flown boosters and beyond.

Dan Drollette calls our attention to America's Strategic National Stockpile for Biodefense, "a little-publicized $7 billion federal agency...key to defending the country from a biological attack."

"Its operators have to prepare for the unthinkable, such as what to do if 100,000 cases of some new disease with pandemic potential appears -- what global health officials have sometimes dubbed 'Disease X.'"

From the Bulletin of the Atomic Scientists: [O]ne of the most surprising features about the stockpile is that in all likelihood, it is probably incomplete. The reason for this is that although the stockpile includes what are presumed to be the best medical countermeasures for a broad range of potential biothreats -- we don't know the exact inventory because the identity of the contents are closely held -- there is an even broader range of potential biothreat agents that an adversary could use in an attack. And stockpiling countermeasures for every conceivable individual agent is currently not feasible because countermeasures for some biothreat agents do not even exist yet -- and even if they did, the continuous maintenance of copious countermeasures may not be logistically or financially feasible. There is also the possibility that an adversary could select or engineer an agent that is simply resistant to all-known medications.

To address this problem, future stockpiles may benefit from an emerging approach to disease treatment: shifting countermeasures from today's emphasis on protein-based vaccines and antitoxins to a new system primarily focused on nucleic acid (DNA and RNA) coding for genes that help the body protect itself from myriad infectious diseases and toxins. This approach offers the long-term prospect of a stockpile that could simultaneously be more comprehensive and vastly cheaper to establish and maintain. Such a future is conceivable because of the accelerated pace of molecular biology research and development of methods to safely transfer (or what specialists refer to as "deliver") synthetic genes into people.

DNA vaccines, for example, are based on the delivery of synthetic genes that code for individual proteins found on a bacteria or a virus -- instead of using the whole pathogen itself as a basis for the vaccine... Once the immune system has established a long-term memory of these recognizable markers, the next time the same pathogen protein appears (now in the context of an infection), the body can immediately identify it as foreign and begin producing large quantities of protective antibodies to fight it. More tantalizing for a future Strategic National Stockpile than improved vaccines -- which would still have a lag time of one-to-two weeks until protection -- is the possibility of bypassing the requirement for immune "education" entirely, and directly delivering genes that code for pathogen-specific antibodies, thereby achieving more rapid protection. The process involves determining the genetic sequence for an antibody that is known to offer protection against a pathogen and then delivering that gene to cells. The body's own cells re-use their existing protein production machinery and become antibody factories, a method termed "antibody gene transfer." It is a form of immunotherapy that has been garnering significant attention lately as a new approach for treating some chronic diseases, such as cancer.

The Guardian reports: An end to the Aids epidemic could be in sight after a landmark study found men whose HIV infection was fully suppressed by antiretroviral drugs had no chance of infecting their partner. The success of the medicine means that if everyone with HIV were fully treated, there would be no further infections...

"It's brilliant -- fantastic. This very much puts this issue to bed," said Prof Alison Rodger from University College London, the co-leader of the paper published in the Lancet medical journal.... Dr Michael Brady, the medical director at the Terrence Higgins Trust, said: "It is impossible to overstate the importance of these findings.

"The Partner study has given us the confidence to say, without doubt, that people living with HIV who are on effective treatment cannot pass the virus on to their sexual partners. This has incredible impact on the lives of people living with HIV and is a powerful message to address HIV-related stigma."

Long-time Slashdot reader nojayuk quotes World Nuclear News (a publication of the World Nuclear Association): The UK's National Nuclear Laboratory (NNL) and University of Leicester have generated usable electricity from the chemical element americium in what it believes to be a global first. The achievement is seen as a step towards potential use of americium in so-called space batteries, which may mean future space missions can be powered for up to 400 years.

Americium is an element not found in nature, but which is produced by the radioactive decay of plutonium -- which itself is produced during the operation of nuclear reactors. A team led by NNL has extracted americium from some of the UK's plutonium stocks, and used the heat generated from this highly radioactive material to generate electric current, which in turn lit up a small light bulb -- all within a specially shielded area of NNL's Central Laboratory in Cumbria, England.

The breakthrough means potential use of americium in radioisotope power systems for missions which would use the heat from americium pellets to power spacecraft heading into deep space or to challenging environments on planet surfaces where other power sources, such as solar panels, no longer function. In this way, NNL said, such space missions can carry on sending back vital images and data to Earth for many decades, far longer than would otherwise be possible.
Tim Tinsley, NNL's account director for the work, calls it "recycling something that is a waste from one industry into a significant asset in another," though he adds that the plutonium is not exactly being recycled. "We 'clean' the americium from it, which would have been a waste. With sufficient applications, all of the UK plutonium could be 'cleaned' of the americium. The returned plutonium is in a better condition, ready for further storage or reuse as nuclear fuel."

Blue Origin successfully performed another test launch of its New Shepard system today. Both the New Shepard rocket and capsule touched down safely back at the company's West Texas facility around 10 minutes after liftoff. The capsule reached about 346,000 feet, or more than 65 miles, eclipsing the recognized boundary of space. Some context: Before today, New Shepard has landed nine out of the 10 times it's flown, and the vehicle has proven that it can keep people safe even in emergency scenarios. However, there still isn't a solid timeline for when the first test passengers will fly on the vehicle, and the company has not started selling tickets to customers yet. The rocket flying this week is the third iteration of the New Shepard vehicle, and the company has built a fourth version that will take the first crews to space. That rocket is supposed to fly sometime this year, according to Blue Origin, but exactly when is still unclear.

Analysis of 30 leading institutions found that just 17% of study results had been posted online as required by EU rules. From a report: Many of Europe's major research universities are ignoring rules that require them to make public the results of clinical trials. A report published on 30 April found that the results of only 162 of 940 clinical trials (17%) that were due to be published by 1 April had been posted on the European Union's trials register. The 30 universities surveyed are those that sponsor the most clinical trials in the EU. Fourteen of these institutions had failed to publish a single results summary. If three high-performing UK universities are excluded from the figures, the results of just 7% of the trials were made public on time. Campaigners say the resulting lack of transparency harms patients by undermining the efforts of doctors and health authorities to provide the best treatments, slows medical progress and wastes public funds.

"Major universities in continental Europe are clearly not investing the effort required to meet their ethical, scientific and regulatory obligations," says report author Till Bruckner, of the UK-based transparency campaign group TranspariMED. A 2004 EU law that came into effect in 2014 requires study sponsors to publish summaries of a trial's results on the European Union Clinical Trials Register (EUCTR) site within 12 months of the trial's completion. Updated laws on clinical trials that are not expected to become legally binding until 2020 specify that there should be penalties for institutions that don't comply with the rules.

A metals manufacturer faked test results and provided faulty materials to NASA, causing more than $700 million in losses and two failed satellite launch missions, according to an investigation by the U.S. space agency. From a report: The fraud involved an Oregon company called Sapa Profiles, which falsified thousands of certifications for aluminum parts over 19 years for hundreds of customers, including NASA. The bad parts were used in the making of Taurus XL, a rocket that was supposed to deliver satellites studying the Earth's climate during missions carried out in 2009 and 2011. The launch vehicle's fairing, a clamshell structure that carries the satellite as it travels through the atmosphere, didn't fully open, causing the unsuccessful launch, according to a statement from NASA.

This week, as scientists work through an exercise simulating an imminent asteroid impact with Earth, NASA's administrator Jim Bridenstine warned the real-world threat should be taken seriously. From a report: Bridenstine acknowledged "the giggle factor," the dismissive response the topic has been met with in the past, at the start of his keynote remarks Monday at the International Academy of Astronautics Planetary Defense Conference in College Park, Maryland. "We have to make sure that people understand that this is not about Hollywood, it's not about movies," he said. "This is about ultimately protecting the only planet we know, right now, to host life and that is the planet Earth." As part of the conference activities, space agencies will also be live-tweeting a fictional exercise simulating what it might be like if such an asteroid were discovered on a collision course with our planet.

Indonesia has announced plans to build a new capital city as its current capital, Jakarta, struggles with pollution, traffic gridlock -- and the fact that the city is sinking. From a report: After a Cabinet meeting on Monday, planning minister Bambang Brodjonegoro said President Joko Widodo has decided to move the capital out of Indonesia's main island, Java. It's not clear exactly when this will happen, or where the new capital would be located. The idea has been out there for decades, though previous leaders have been unable to accomplish the ambitious plan. Earlier this month, Widodo secured another term in office, according to independent polling organizations. His challenger also declared victory, and official results have not yet been announced.

"The idea to move the capital city appeared long ago. ... But it has never been decided or discussed in a planned and mature manner," Widodo said before the meeting, according to The Associated Press. Jakarta faces massive challenges. As the BBC has reported, it's the fastest-sinking city in the world, with almost half of its area below sea level.

From a report on The Atlantic: In 2014, a few hackers realized that the security flaw in certain Medtronic pumps could be exploited for a DIY revolution. Type 1 diabetes is a disease where the pancreas is unable to produce insulin to control blood sugar. For years, Boss (the anecdote in the story who purchased used insulin pumps from some dealer on Craiglist) had counted, down to the gram, the carbohydrates in every meal and told his pump how much insulin to dispense. [...] By 2014, the hardware components of a DIY artificial pancreas -- a small insulin pump that attaches via thin disposable tubing to the body and a continuous sensor for glucose, or sugar, that slips just under the skin -- were available, but it was impossible to connect the two. That's where the security flaw came in. The hackers realized they could use it to override old Medtronic pumps with their own algorithm that automatically calculates insulin doses based on real-time glucose data. It closed the feedback loop.

They shared this code online as OpenAPS, and "looping," as it's called, began to catch on. Instead of micromanaging their blood sugar, people with diabetes could offload that work to an algorithm. In addition to OpenAPS, another system called Loop is now available. Dozens, then hundreds, and now thousands of people are experimenting with DIY artificial-pancreas systems -- none of which the Food and Drug Administration has officially approved. And they've had to track down discontinued Medtronic pumps. It can sometimes take months to find one. Obviously, you can't just call up Medtronic to order a discontinued pump with a security flaw. "It's eBay, Craigslist, Facebook. It's like this underground market for these pumps," says Aaron Kowalski, a DIY looper and also CEO of JDRF, a nonprofit that funds type 1 diabetes research. This is not exactly how a market for lifesaving medical devices is supposed to work. And yet, this is the only way it can work -- for now.

The number of measles cases in the United States has reached a 25-year peak, propelled by the spread of misinformation about the vaccine that can prevent the disease, federal health officials said on Monday. From a report: The U.S. Centers for Disease Control and Prevention reported 704 cases as of April 26, a 1.3 percent increase since the most recent tally of 695 reported on Wednesday. The vast majority of cases have occurred in children who have not received the measles-mumps-rubella vaccine, which confers immunity to the disease, officials said. "The suffering we are seeing today is completely avoidable," U.S. Health and Human Services Secretary Alex Azar said on Monday. "We know vaccines are safe because they're among some of the most studied medical products we have." A vocal fringe of U.S. parents refuse to vaccinate their children believing, contrary to scientific evidence, that ingredients in them can cause autism or other disorders.

Materials researchers use synthetic hydrogels which mimic the features of human muscles -- they''re strong, soft, full of water, and resistant to fatigue. Now researchers have discovered they mimic human muscles in another way, writes technology_dude: MIT researchers have found a way to give synthetic hydro gels human muscle characteristics: by taking the hyrdogels "to the gym"... The gym workout basically consisted of repeatedly stretching the material while in a water bath, [which] causes nanofibers to align "to produce a strong, soft, and hydrated material that resists breakdown or fatigue over thousands of repetitive movements," Phys.org reports.
The hydrogels can also be 3D-printed into different shapes, and the researchers believe the materials could one day be used for sensitive biomedical implants like heart valves, cartilage replacements, and spinal disks -- and for "soft robots."

An experimental psychologist at the University of Oxford argues that in two decades, "we will look back on the past 60 years -- particularly in biomedical science -- and marvel at how much time and money has been wasted on flawed research." [M]any researchers persist in working in a way almost guaranteed not to deliver meaningful results. They ride with what I refer to as the four horsemen of the reproducibility apocalypse: publication bias, low statistical power, P-value hacking and HARKing (hypothesizing after results are known). My generation and the one before us have done little to rein these in. In 1975, psychologist Anthony Greenwald noted that science is prejudiced against null hypotheses; we even refer to sound work supporting such conclusions as 'failed experiments'...

The problems are older than most junior faculty members, but new forces are reining in these four horsemen. First, the field of meta-science is blossoming, and with it, documentation and awareness of the issues. We can no longer dismiss concerns as purely theoretical. Second, social media enables criticisms to be raised and explored soon after publication. Third, more journals are adopting the 'registered report' format, in which editors evaluate the experimental question and study design before results are collected -- a strategy that thwarts publication bias, P-hacking and HARKing. Finally, and most importantly, those who fund research have become more concerned, and more strict. They have introduced requirements that data and scripts be made open and methods be described fully.

I anticipate that these forces will soon gain the upper hand, and the four horsemen might finally be slain.

The world's top asteroid experts are gathering on Monday, April 29 at the 2019 Planetary Defense Conference in Washington D.C. to take part in a hypothetical asteroid impact exercise that will test how Earth responds to the threat of a potentially devastating space rock. CNET reports: NASA's Planetary Defense Coordination Office developed the exercise along with the U.S. Federal Emergency Management Agency. "The point is to investigate how NEO observers, space agency officials, emergency managers, decision makers, and citizens might respond to an actual impact prediction and evolving information," NASA said. The ESA Operations Twitter account is now live-tweeting the entire scenario, from the discovery of the asteroid (named 2019PDC) to the increasingly grim odds it might hit Earth. The first tweet sounds innocuous. It's a casual mention of international news reports confirming the asteroid's discovery.

The team is appending each tweet with the all-caps hashtag #FICTIONALEVENT so no one will freak out. It's still sobering to follow the events, which recently worsened from a 1 in 250 chance of impact to 1 in 100. ESA Operations will continue to update the plot in the coming week. Participants will receive daily briefings and must role-play the responses from astronomers, space agencies and governments. In reality, we know of no imminent threats from asteroids, but NASA is constantly tracking their movements through space.

An anonymous reader quotes a report from The Wall Street Journal: Special agents from the Federal Bureau of Investigation searched the offices of lab-test startup uBiome Inc. on Friday morning (Warning: source paywalled; alternative source), according to a person with knowledge of the matter. The FBI is investigating uBiome's billing practices. An FBI spokeswoman said, "I can confirm that special agents from the FBI San Francisco Division are present at 360 Langton Street in San Francisco conducting court-authorized law-enforcement activity. Due to the ongoing nature of the investigation, I cannot provide any additional details at this time." According to public records, uBiome has a headquarters office at that address.

uBiome sells tests for the microbiome, which refers to the group of microorganisms that live in the digestive tract and other parts of the body, under names including Explorer and SmartGut. The company, which calls itself the "leading microbial genomics company," was one of the earliest firms in the microbiome testing field, launching in 2012 with a crowdfunding campaign that raised $350,000. Last year, uBiome said it had raised $83 million from firms including OS Fund and Y Combinator. uBiome describes its SmartGut and SmartJane tests as "an insurance-reimbursed test ordered by a health-care provider." "We are cooperating fully with federal authorities on this matter. We look forward to continuing to serve the needs of healthcare providers and patients," a spokeswoman for uBiome said Friday. In an interview last week that included questions about scrutiny of uBiome's billing practices, uBiome Chief Executive Jessica Richman said that "compliance is our highest value" and that uBiome's billing and other practices are proper.

Slashdot reader The Snazster shares a report from ScienceDaily, reporting on materials provided by Johns Hopkins University: New measurements from NASA's Hubble Space Telescope confirm that the Universe is expanding about 9% faster than expected based on its trajectory seen shortly after the big bang, astronomers say. The new measurements, published April 25 in the Astrophysical Journal Letters, reduce the chances that the disparity is an accident from 1 in 3,000 to only 1 in 100,000 and suggest that new physics may be needed to better understand the cosmos.

In this study, [Adam Riess, Bloomberg Distinguished Professor of Physics and Astronomy at The Johns Hopkins University, Nobel Laureate and the project's leader] and his SH0ES (Supernovae, H0, for the Equation of State) Team analyzed light from 70 stars in our neighboring galaxy, the Large Magellanic Cloud, with a new method that allowed for capturing quick images of these stars. The stars, called Cepheid variables, brighten and dim at predictable rates that are used to measure nearby intergalactic distances. The usual method for measuring the stars is incredibly time-consuming; the Hubble can only observe one star for every 90-minute orbit around Earth. Using their new method called DASH (Drift And Shift), the researchers using Hubble as a "point-and-shoot" camera to look at groups of Cepheids, thereby allowing the team to observe a dozen Cepheids in the same amount of time it would normally take to observe just one. [...] As the team's measurements have become more precise, their calculation of the Hubble constant has remained at odds with the expected value derived from observations of the early universe's expansion by the European Space Agency's Planck satellite based on conditions Planck observed 380,000 years after the Big Bang. "This is not just two experiments disagreeing," Riess explained. "We are measuring something fundamentally different. One is a measurement of how fast the universe is expanding today, as we see it. The other is a prediction based on the physics of the early universe and on measurements of how fast it ought to be expanding. If these values don't agree, there becomes a very strong likelihood that we're missing something in the cosmological model that connects the two eras."

An anonymous reader quotes a report from Phys.Org: The celestial phenomenon known as STEVE is likely caused by a combination of heating of charged particles in the atmosphere and energetic electrons like those that power the aurora, according to new research. In a new study, scientists found STEVE's source region in space and identified two mechanisms that cause it. Last year, the obscure atmospheric lights became an internet sensation. Typical auroras, the northern and southern lights, are usually seen as swirling green ribbons spreading across the sky. But STEVE is a thin ribbon of pinkish-red or mauve-colored light stretching from east to west, farther south than where auroras usually appear. Even more strange, STEVE is sometimes joined by green vertical columns of light nicknamed the "picket fence."

Authors of a new study published in AGU's journal Geophysical Research Letters analyzed satellite data and ground images of STEVE events and conclude that the reddish arc and green picket fence are two distinct phenomena arising from different processes. The picket fence is caused by a mechanism similar to typical auroras, but STEVE's mauve streaks are caused by heating of charged particles higher up in the atmosphere, similar to what causes light bulbs to glow. "Aurora is defined by particle precipitation, electrons and protons actually falling into our atmosphere, whereas the STEVE atmospheric glow comes from heating without particle precipitation," said Bea Gallardo-Lacourt, a space physicist at the University of Calgary and co-author of the new study. "The precipitating electrons that cause the green picket fence are thus aurora, though this occurs outside the auroral zone, so it's indeed unique."

UCLA professor Yang Yang's lab chock-full of coffee drinkers spent several years searching for a stability-enhancing additive to turn famously unstable perovskite PV cells into a useful product. Then, on a lark, Yang's graduate student Rui Wang suggested they try adding caffeine to the mix. To the team's surprise, caffeine produced longer lasting and more powerful solar cells. IEEE Spectrum reports: The work, completed with collaborators at Hong Kong-based PV firm Solargiga Energy Holdings and two Chinese universities, appears today in energy research journal Joule. Caffeine's calming effect starts during the creation of perovskite crystals. "Without caffeine, the crystallization process will just take 2 seconds, but with caffeine it will take 1 to 2 minutes," says Yang. The more deliberate growth process yields a perovskite material with larger grains of defect-free crystal. They are more stable mechanically and better at moving the charges created from incoming photons.

Caffeine also stabilizes perovskite PV cells during operation because each caffeine molecule can bind to two lead atoms at the boundaries of the crystal grains. This dual molecular lock ties the grains together and, Yang believes, hinders the movement of ions that threaten to reshape the crystal into a weaker pattern. The lab's best caffeine-treated cell captures incoming light with an efficiency of 19.8 percent, up from 17 percent for untreated cells, and retains 86 percent of its output after operating for 1,300 grueling hours at 85C. That's remarkable endurance compared with that of the lab's untreated cells, whose output plummeted by 40 percent after just 175 hours. Still, Yang says they need materials that hold it together through at least one to two years of accelerated testing to provide confidence that they can pump out power for several decades on a rooftop.