Medicine

Apple Watch Can Accurately Assess Frailty, Finds Stanford Study (macrumors.com) 15

The Apple Watch can accurately determine a user's "frailty," according to the findings of a recently-published study from Stanford University. MacRumors reports: Frailty can be determined using a six-minute walking test (6MWT), and the metric is a general standard used to evaluate the functional mobility and exercise capacity of a patient. Higher scores indicate "healthier cardiac, respiratory, circulatory, and neuromuscular function," according to Apple. Conducted by Stanford University researchers and funded by Apple, the study provided 110 Veterans Affairs patients with cardiovascular disease with an iPhone 7 and Apple Watch Series 3. Patients conducted regular at-home six-minute walking tests, which were then compared to their standard in-clinic 6MWT performance.

The study found that an Apple Watch was able to accurately assess frailty with a sensitivity of 90 percent and specificity of 85 percent when supervised in a clinical setting. When assessed in an unsupervised setting at home, the Apple Watch was able to accurately assess frailty with a sensitivity of 83 percent and specificity of 60 percent. The findings indicate that passive activity data gathered by the Apple Watch is an accurate predictor of in-clinic 6MWT performance.

Security

'Incompetent Developers' Blamed For NZ Patient Privacy Breach of COVID-19 Vaccine Booking Systems (stuff.co.nz) 54

An anonymous reader writes: The New Zealand Ministry of Health has launched a "sweeping review" of the nation's COVID vaccine-booking system, after a data breach led to exposure of personal information for more than 700 patients. A whistleblower reported over the weekend that they could access information about other patients, which was "readily accessible within the public-facing code of the website" -- apparently hard coded.

As a response, the Ministry of Health has ordered a review of all systems made by the developer, Valentia Technologies, which also makes software used by the Ambulance service, many GP practices, and the managed isolation and quarantine system.
"It is not a coding error. It is incompetence. The developer who developed this is incompetent ... This is basic stuff," said the man who spotted the booking system problem.

"The source code of the website, flagged a few concerning features, including someone's name, and an NHI number hard coded into the website, for what reason? I don't know," he said. "We could see everyone's details. We skimmed through, we didn't look at names, but their names, dates of birth, NHI numbers for those who entered them, contact details, where they were getting their vaccinations, what time they were vaccinated."

He said it appeared that Canterbury DHB had used a modified internal system to create the booking system. "You can tell by the source code, this was never meant to be a public facing website. This was only for people to use on like iPads, in doctors' surgeries, it was not supposed to be for this."
Medicine

Stanford Scientists Reverse Engineer Moderna Vaccine, Post Code On Github (vice.com) 111

An anonymous reader quotes a report from Motherboard: Stanford scientists saved drops of the COVID-19 vaccine destined for the garbage can, reverse engineered them, and have posted the mRNA sequence that powers the vaccine on GitHub for all to see. The GitHub post is four pages long. The first two are an explanation by the team of scientists about the work, the second two pages are the entire mRNA sequence for the Moderna COVID-19 vaccine. "RNA vaccines have become a key tool in moving forward through the challenges raised both in the current pandemic and in numerous other public health and medical challenges," the scientists said on GitHub. "Despite their ubiquity, sequences are not always available for such RNA. Standard methods facilitate such sequencing."

According to Stanford scientists Andrew Fire and Massa Shoura, this isn't technically "reverse-engineering" a vaccine. "We didn't reverse engineer the vaccine. We posted the putative sequence of two synthetic RNA molecules that have become sufficiently prevalent in the general environment of medicine and human biology in 2021," they told Motherboard in an email. "As the vaccine has been rolling out, these sequences have begun to show up in many different investigational and diagnostic studies. Knowing these sequences and having the ability to differentiate them from other RNAs in analyzing future biomedical data sets is of great utility." [...] According to Shoura and Fire, the FDA cleared the Stanford project's decision to share the sequence with the community. "We did contact Moderna a couple of weeks ago to indicate that we were hoping to include the sequence in a publication and asking if there was anything that we should reference with respect to this... no response or objection from them, so we assume that everyone is busy doing important work."

China

WHO Report Says Animals Likely Source of COVID (apnews.com) 287

A joint WHO-China study on the origins of COVID-19 says that transmission of the virus from bats to humans through another animal is the most likely scenario and that a lab leak is "extremely unlikely," The Associated Press reported Monday, citing a draft copy. From the report: The findings offer little new insight into how the virus began to spread around the globe and many questions remain unanswered, though that was as expected. But the report did provide more detail on the reasoning behind the researchers' conclusions. The team proposed further research in every area except the lab leak hypothesis. The report's release has been repeatedly delayed, raising questions about whether the Chinese side was trying to skew the conclusions to prevent blame for the pandemic falling on China. A World Health Organization official said late last week that he expected it would be ready for release "in the next few days."

The AP received a copy on Monday from a Geneva-based diplomat from a WHO-member country. It wasn't clear whether the report might still be changed prior to release, though the diplomat said it was the final version. A second diplomat confirmed getting the report too. Both refused to be identified because they were not authorized to release it ahead of publication. The researchers listed four scenarios in order of likelihood for the emergence of the coronavirus named SARS-CoV-2. Topping the list was transmission from bats through another animal, which they said was likely to very likely. They evaluated direct spread from bats to humans as likely, and said that spread through "cold-chain" food products was possible but not likely. Bats are known to carry coronaviruses and, in fact, the closest relative of the virus that causes COVID-19 has been found in bats. However, the report says that "the evolutionary distance between these bat viruses and SARS-CoV-2 is estimated to be several decades, suggesting a missing link."

Medicine

'No Evidence' to Support Trump CDC Director's Theory about Coronavirus Origin (cbsnews.com) 469

While President Trump's former CDC director says he still thinks SARS-Cov-2 somehow originated from a lab in China, "a team of experts from the World Health Organization, Dr. Anthony Fauci, and a number of virology experts have said the evidence to support such a claim just isn't there," reports CBS News: Redfield, a virologist who headed the CDC under President Trump, stressed several times that this is just his opinion, not a proven fact. "I'm allowed to have opinions now," he said... Dr. Anthony Fauci addressed Redfield's comments at Friday's COVID-19 response briefing and suggested that most public health officials disagree.... Kristian G. Andersen, director of the infectious disease genomics, translational research institute at Scripps Research, told CBS News that "none of (Redfield's) comments" on the lab theory are "backed by available evidence."

"It is clear that not only was he the most disastrous CDC director in U.S. history where he utterly failed in his sworn mission to keep the country safe, but via his comments, he also shows a complete lack of basic evolutionary virology," Andersen said.

Andersen was the lead author of a study published in Nature Medicine last year which found that the virus was a product of natural evolution. Furthermore, through analysis of public genome sequence data, the scientists "found no evidence that the virus was made in a laboratory or otherwise engineered," according to a press release from Scripps. "By comparing the available genome sequence data for known coronavirus strains, we can firmly determine that SARS-CoV-2 originated through natural processes," Andersen said at the time. W. Ian Lipkin, a study co-author with Andersen and the director of the Center for Infection and Immunity at Columbia's Mailman School of Public Health, said that while there's still a lot we don't know about the virus, including exactly how long it's been circulating, there is "no evidence" to suggest that it was created in a lab...

Andersen noted that "We know that the first epidemiologically linked cluster of cases came from the Huanan market and we know the virus was found in environmental samples — including animal cages — at the market," he said. "Any 'lab leak' theory would have to account for that scenario — which it simply can't, without invoking a major conspiracy and cover up by Chinese scientists and authorities."

His scathing conclusion: "Redfield has no idea what he's talking about — plain and simple. It's no surprise given his disastrous tenure as CDC director."

Medicine

Trump's Former CDC Director Says He Still Thinks SARS-CoV-2 Originated In a Lab (axios.com) 236

Beeftopia shares a report from Axios: Former CDC Director Robert Redfield told CNN on Friday that he believes the coronavirus "escaped" from the Wuhan Institute of Virology, and that it was spreading as early as September or October of 2019 -- though he stressed that it was his "opinion." "I'm of the point of view that I still think the most likely etiology of this pathology in Wuhan was from a laboratory. Escaped. Other people don't believe that. That's fine. Science will eventually figure it out," Redfield told CNN's Sanjay Gupta... "That's not implying any intentionality. It's my opinion, right...?"
Axios calls it "a stunning assertion, offered with little evidence," even though Redfield "is a career virologist," argues Slashdot reader Beeftopia. "He received his medical degree from Georgetown University before conducting his residency at the Walter Reed Army Medical Center as a US Army officer. Both of his parents were scientists at the National Institutes of Health. Before starting his position as the director of the CDC, Redfield was a professor at the University of Maryland School of Medicine and was once one of the US Army's leading AIDS researchers. He does have a controversial incident regarding an AIDS vaccine on which his lab was working." In fact, Kaiser Health News reports Redfield had been the principal investigator for clinical trials of a treatment vaccine: "Either he was egregiously sloppy with data or it was fabricated," said former Air Force Lt. Col. Craig Hendrix, a doctor who is now director of the division of clinical pharmacology at Johns Hopkins University School of Medicine. "It was somewhere on that spectrum, both of which were serious and raised questions about his trustworthiness...." Washington Senator Patty Murray, the ranking Democrat on the health committee, cited the research controversy as an example of a "pattern of ethically and morally questionable behavior" by Redfield that should prompt the president to reconsider the appointment.
Earlier this month, a member of the WHO investigative team said wildlife farms in southern China are the most likely source of the COVID-19 pandemic. Peter Daszak, a disease ecologist with EcoHealth Alliance and part of the WHO delegation that traveled to China earlier this year, told NPR that the Chinese government thought those farms were the most probable pathway for a coronavirus in bats in southern China to reach humans in Wuhan.
Medicine

Biden Sets New Covid Vaccine Goal of 200 Million Shots Within His First 100 Days (cnbc.com) 198

President Joe Biden on Thursday announced a new goal of having 200 million Covid vaccination shots being distributed within his first 100 days in office. From a report: "I know it's ambitious -- twice our original goal -- but no other country in the world has come close ... to what we're doing," Biden told reporters as he opened his first news conference as president. "I believe we can do it." As of Friday, 100 million coronavirus vaccinations had been given since Biden was inaugurated. That benchmark -- which Biden set as his original target Dec. 8 -- was reached on his 59th day in office. After a slower-than-expected rollout under former President Donald Trump, the pace of vaccinations in the United States has rapidly increased and has been averaging about 2.5 million doses per day in the past week. If that vaccination rate is maintained, Biden's 200-million-dose target would be hit in about five weeks, or around April 23 -- a full week before Biden would mark 100 days in the White House. The federal government has a deal with Johnson & Johnson for delivery of 200 million doses. The first half of that order expected by the end of June. Merck is helping to make J&J's shot, which is a single-dose vaccination.
Math

The Solution of the Zodiac Killer's 340-Character Cipher (wolfram.com) 46

Sam Blake, writing at Wolfram Blog: The Zodiac Killer (an unidentified American serial killer active during the 1960s and 70s) sent numerous taunting letters to the press in the San Francisco area with regard to a local murder spree. In these letters, the killer took responsibility for the crimes and threatened to commit further murders. He also included three ciphers, each containing one-third of a 408-character cryptogram. The killer claimed that this cryptogram would reveal his identity when deciphered. The killer sent the fourth and final cipher (discussed in the linked post) to the San Francisco Chronicle after the 408-character cryptogram, deciphered in 1969, did not reveal the killer's identity.

In 2020, Melbourne, Australia, had a 112-day lockdown of the entire city to help stop the spread of COVID-19. The wearing of masks was mandatory and we were limited to one hour a day of outside activity. Otherwise, we were stuck in our homes. This gave me lots of time to look into interesting problems I'd been putting off for years. I was inspired by a YouTube video by David Oranchak, which looked at the Zodiac Killer's 340-character cipher (Z340), which is pictured below. This cipher is considered one of the holy grails of cryptography, as at the time the cipher had resisted attacks for 50 years, so any attempts to find a solution were truly a moonshot.

Science

Atomic Clocks Compared With Astounding Accuracy (nature.com) 33

The remarkable accuracy of atomic clocks makes them excellent instruments for timekeeping and other precision measurements. From a report: Writing in Nature, the Boulder Atomic Clock Optical Network (BACON) Collaboration reports extremely accurate comparisons of three world-leading clocks in Boulder, Colorado, housed at the National Institute of Standards and Technology (NIST) and the JILA research institute. The authors show how their clock comparisons provide insights into fundamental physics and represent substantial progress towards redefining the second in the International System of Units (SI). Atomic clocks 'tick' at a rate determined by the frequency of light that is emitted or absorbed when an atom changes from one energy state to another. Clocks based on different atoms run at different rates, and the term 'optical clock' refers to one that runs at an optical frequency. Three of the worldâ(TM)s best optical clocks are the aluminium-ion and ytterbium clocks at NIST and the strontium clock at JILA. The measured frequencies of all three clocks are estimated to be correct to within a fractional uncertainty of 2 parts in 10^18 or better.

This level of uncertainty could, in principle, allow the clocks to keep time so accurately that they would gain or lose no more than one second over the age of the Universe. Such optical clocks would be 100 times more accurate than caesium clocks. There is therefore a desire to redefine the SI second in terms of an optical-clock frequency and to move away from the current definition based on caesium. But before such a redefinition is possible, scientists must build confidence in the reproducibility of optical clocks through a series of clock comparisons. The target accuracy for these comparisons is at the level of parts in 10^18 to clearly demonstrate the superiority of optical clocks over caesium clocks.

Science

Venus Flytraps Have Magnetic Fields Like the Human Brain (vice.com) 33

An anonymous reader shares a report from Motherboard (Editor's note: the article was written last week based on findings published in January): [F]or the first time in history, a group of mavericks out of Switzerland have detected a magnetic signal in a plant. Using a highly sensitive magnetometer, an interdisciplinary team of researchers have measured signals from a Venus flytrap of up to .5 picotesla. To make matters even more mind-blowing, this signal is roughly equivalent to the biomagnetic field strength of the human brain. The full report is here.

The Venus flytrap boasts three trigger hairs that serve as mechanosensors. When a prey insect touches a trigger hair, an Action Potential is generated and travels along both trap lobes. If a second touch-induced Action Potential is fired within 30 seconds, the energy stored in the open trap is released and the capture organ closes. This is the plant-insect equivalent of a repeat offender. Imprisonment ensues. Crucial to making these findings was the fact that this electrical activity doesn't carry into the stalk of traps, which allowed the researchers to isolate the lobe by slicing it from the rest of the plant. Biologically intact, it was then placed on to a sensor. [...] The discovery is as huge for biomagnetism in plants as it is for electro-physiology in general. We now have proof of a pathway for long-distance signal propagation between plant cells.
"[I]n the future, magnetometry may be used to study long-distance electrical signaling in a variety of plant species, and to develop noninvasive diagnostics of plant stress and disease," the report says. Crops could be scanned for temperature shifts, chemical changes, or pests without having to damage the plants themselves.
Science

Scientists Discover How Humans Develop Larger Brains Than Other Apes (phys.org) 77

fahrbot-bot shares a report from Phys.org: A new study is the first to identify how human brains grow much larger, with three times as many neurons, compared with chimpanzee and gorilla brains. The study, led by researchers at the Medical Research Council (MRC) Laboratory of Molecular Biology in Cambridge, UK, identified a key molecular switch that can make ape brain organoids grow more like human organoids, and vice versa. The study, published in the journal Cell, compared "brain organoids" -- 3-D tissues grown from stem cells which model early brain development -- that were grown from human, gorilla and chimpanzee stem cells.

During the early stages of brain development, neurons are made by stem cells called neural progenitors. These progenitor cells initially have a cylindrical shape that makes it easy for them to split into identical daughter cells with the same shape. The more times the neural progenitor cells multiply at this stage, the more neurons there will be later. As the cells mature and slow their multiplication, they elongate, forming a shape like a stretched ice-cream cone. Previously, research in mice had shown that their neural progenitor cells mature into a conical shape and slow their multiplication within hours. They found that in gorillas and chimpanzees this transition takes a long time, occurring over approximately five days.

Human progenitors were even more delayed in this transition, taking around seven days. The human progenitor cells maintained their cylinder-like shape for longer than other apes and during this time they split more frequently, producing more cells. This difference in the speed of transition from neural progenitors to neurons means that the human cells have more time to multiply. This could be largely responsible for the approximately three-fold greater number of neurons in human brains compared with gorilla or chimpanzee brains.

Mars

'Wright Brothers Moment': NASA To Fly Ingenuity Mars Helicopter in Early April (bbc.com) 19

The US space agency says it expects now to fly the first helicopter on Mars in early April. From a report: The little chopper was carried to the Red Planet by the Perseverance rover, which made its dramatic landing in Jezero Crater just over a month ago. Called Ingenuity, the 1.8kg, twin-rotor aircraft will attempt a series of short hops in Mars' rarefied air. If successful, it would represent something of a "Wright Brothers moment", says Nasa. This is a reference of course to Orville and Wilbur Wright, who in 1903 conducted the historic first heavier-than-air, powered aircraft flight here on Earth. And to mark the connection, the agency revealed that a postage stamp-sized piece of fabric from a wing of the brothers' plane has been taped to Ingenuity.

At the moment, the chopper is still attached to Perseverance, to its belly. A protective covering was released at the weekend and in the coming days the craft will be lowered to the ground. Engineers have identified a 10m by 10m area in Jezero that they're calling the "airfield". This is at one end of a 90m "flight zone", inside which perhaps five sorties will be performed. Perseverance will endeavour to record everything on camera. "We are going to do our very best to capture Ingenuity in flight," said Nasa engineer Farah Alibay. "We're going to be taking images, we're hoping to take video." This will be challenging, she cautioned. Both rover and helicopter function autonomously and carry separate clocks. The timing devices will need to be in sync for the photography to catch the action.

Robotics

Researchers Found a Way To Send Tiny Robots Into Mouse Brains (gizmodo.com) 22

An anonymous reader quotes a report from Gizmodo: In a mind-bending development, a team of researchers in China have managed to treat brain tumors in mice by delivering drugs to the tissues using microscopic robots. The robots jumped from the mice's bloodstreams into their brains by being coated in E. coli, which tricked the rodents' immune systems into attacking them, absorbing the robots and the cancer-fighting drugs in the process. The team's research was published today in the journal Science Robotics. It comes on the heels of previous research by members of the same team, which saw liquid-coated nanorobots remotely propelled through the jelly-like fluid of the eye. Besides being an obvious recipe for an episode of "The Magic School Bus," the research had obvious applications for ophthalmological research and medical treatments.

The crafts are magnetic, and the researchers use a rotating magnetic field to pull them around remotely. On microscales -- we're talking incremental movements about 1% the width of a hair -- the researchers were able to make the hybrid bio-bots wend paths like in the video game Snake. They're dubbed "neutrobots" because they infiltrate the brain in the casing of neutrophils, a type of white blood cell. It ultimately took Wu's team eight years to actualize the microscopic robot swarms capable of bridging the gap between the rodent bloodstream in the animal's tail, where the bots were injected, and its brain, where gliomas -- tumors that emerge from the brain's glial cells -- resided. Part of the issue is that the mice's white blood cells didn't dig the flavor of the magnetic robots. To overcome that issue, Wu's team coated the bots in bits of E. coli membrane, which the white blood cells easily recognize as a unwelcome invader. That made the robots much more palatable, and the white blood cells enveloped them. From inside those cells, the robots were then able to roll the cells toward the brain; a Trojan horse for the 21st century (in this case, one that benefits the residents of Troy). The neutrobots made it into the brains and were able to deliver the drug directly to the targeted tumors.

News

Suez Canal Blocked After Giant Container Ship Gets Stuck (nytimes.com) 135

Trying to convey the sheer scale of the nearly quarter-mile-long container ship that has been stuck in the Suez Canal since Tuesday evening, some news outlets compared it to the length of four soccer fields. Others simply called it gigantic. From a report: But the main thing to know was this: After powerful winds forced the ship aground on one of the canal's banks, it was big enough to block nearly the entire width of the canal, producing a large traffic jam in one of the world's most important maritime arteries. By Wednesday morning, more than 100 ships were stuck at each end of the 120-mile canal, which connects the Red Sea to the Mediterranean and carries roughly 10 percent of worldwide shipping traffic. Only the Panama Canal looms as large in the global passage of goods. "The Suez Canal is the choke point," said Capt. John Konrad, founder of the shipping news website gCaptain.com, noting that 90 percent of the world's goods are transported on ships. It "could not happen in a worse place," he said, "and the timing's pretty bad, too."

The potential fallout is vast. The vessels caught in the bottleneck or expected to arrive there in the coming days include oil tankers carrying about one-tenth of a day's total global oil consumption, according to Kpler, a market research firm, to say nothing of the rest of the cargo now waiting to traverse the canal. And if the ship is not freed within a few days, it would add one more burden to a global shipping industry already reeling from the coronavirus pandemic, creating delays, shortages of goods and higher prices for consumers. The ship, the Ever Given, was heading from China to the port of Rotterdam in the Netherlands. It ran aground amid poor visibility and high winds from a sandstorm that struck much of northern Egypt this week, according to George Safwat, a spokesman for the Suez Canal Authority. The storm caused an "inability to direct the ship," he said in a statement.

Science

Why Airlifting Rhinos Upside Down is Critical To Conservation (cnn.com) 14

Swinging above the African savannah, an upside-down rhino suspended from a helicopter looks comically surreal. But for the black rhino, flying to new territory is no laughing matter -- it's about survival. From a report: Most rhino translocations are carried out with trucks, but some remote locations can't be reached by road. So ten years ago, conservationists began using helicopters, on an occasional basis, to move rhinos to and from inaccessible terrain. The rhino is either placed on its side on a stretcher, or hung upside down by its legs. Conservationists like the upside-down airlift because it's faster, easier and less expensive than the stretcher option, but until now it hasn't been clear how being flipped affects the rhinos. Seeking to find out, the Namibian government asked a research team at Cornell's College of Veterinary Medicine to look into the practice. The results, published in January, were surprising. "We were anticipating that the rhinos would fare worse hanging upside down," says Robin Radcliffe, a senior lecturer in wildlife and conservation medicine. Instead, Radcliffe and his team found that although it looks like an uncomfortable experience, upside-down flying is the better option for rhino health. [...] Radcliffe says the upside-down position allows the spine to stretch which helps to open the airways. Additionally, the team found that when lying on their side, rhinos have a larger "dead space" -- the amount of air in each breath that does not contribute oxygen to the body. The difference between the two postures was small, but because the strong anaesthetic used on the rhino causes hypoxemia -- low oxygen levels in the blood -- even a minor improvement makes a difference to the rhino's welfare.
Space

Detailed Image of a Black Hole's Magnetic Field May Explain How Matter Fuels Powerful Jets (sciencemag.org) 8

The team that in 2019 brought you the first image of a black hole is now offering a new twist on that iconic view. From a report: The thin lines spiraling toward the central black hole shadow in the image above show emissions with different polarizations -- the direction in which light waves vibrate. Light is polarized if it passes through a magnetic field, so the spiraling lines point to the twisting magnetic field lines near the black hole's event horizon. As the Event Horizon Telescope (EHT) team describes today in a pair of papers in Astrophysical Journal, the new picture uses the same data as in the original image, produced from a series of observations in 2017 of the supermassive black hole at the core of nearby galaxy M87, using the combined collecting power of eight radio observatories across the world. To extract the polarization information, the data have gone through many months of additional analysis.

Seeing the magnetic field will help astrophysicists solve an enduring mystery: how matter, sucked in from a swirling disk around the black hole's equator, can sometimes feed a powerful jet of matter and energy spewing from its poles. M87's black hole has a jet that extends 5000 light-years away from the galaxy. The EHT team says the orientation of the magnetic field lines suggests they help push matter outward, against the pull of the black hole's gravity, a process that may funnel some of it toward the jet.

Space

Astronomer Makes Navigation System For Interstellar Space Travel (sciencealert.com) 68

rushtobugment shares a report from ScienceAlert: Using the positions and shifting light of stars, both near and far, astronomer Coryn A.L. Bailer-Jones has demonstrated the feasibility of autonomous, on-the-fly navigation for spacecraft traveling far beyond the Solar System. "When traveling to the nearest stars, signals will be far too weak and light travel times will be of order years," Bailer-Jones wrote in his paper, which is currently available on the preprint server arXiv, where it awaits peer review from the astronomy community. "An interstellar spacecraft will therefore have to navigate autonomously, and use this information to decide when to make course corrections or to switch on instruments. Such a spacecraft needs to be able to determine its position and velocity using only onboard measurements."

With a catalog of stars, Bailer-Jones was able to show that it's possible to work out a spacecraft's coordinates in six dimensions -- three in space and three in velocity -- to a high accuracy, based on the way the positions of those stars changes from the spacecraft's point of view. "As a spacecraft moves away from the Sun, the observed positions and velocities of the stars will change relative to those in a Earth-based catalog due to parallax, aberration, and the Doppler effect," he wrote. "By measuring just the angular distances between pairs of stars, and comparing these to the catalog, we can infer the coordinates of the spacecraft via an iterative forward-modeling process."

Bailer-Jones tested his system using a simulated star catalog, and then on nearby stars from the Hipparcos catalog compiled in 1997, at relativistic spacecraft speeds. Although this is not as accurate as Gaia, that's not terribly important - the aim was to test that the navigation system can work. With just 20 stars, the system can determine the position and velocity of a spacecraft to within 3 astronomical units and 2 kilometers per second (1.24 miles per second). This accuracy can be improved inverse to the square root of the number of stars; with 100 stars, the accuracy came down to 1.3 astronomical units and 0.7 kilometers per second. [...] The system hasn't taken stellar binaries into consideration, nor has it considered the instrumentation. The aim was to show that it could be done, as a first step towards actualizing it. It's even possible that it could be used in tandem with pulsar navigation so that the two systems might be able to minimize each other's flaws.

Science

The LHC Finds a Tantalizing Hint of New Physics (bbc.com) 64

ytene writes: As reported by the BBC, a team at the Large Hadron Collider (LHC) are reporting a hint of new physics thanks to analysis of results from exploring the so-called beauty quark. Results from the LHCb are currently standing at three-sigma -- offering a roughly one-in-one-thousand chance that the measurements reported are a statistical coincidence, still considered short of the so-called "gold-standard" of five-sigma [in which there is a one in 3.5 million chance of the result being a fluke]. If further analysis and experiments confirm these results, they might point the way to an as-yet undiscovered particle, hints of something beyond the Standard Model.
Medicine

US Health Officials Question AstraZeneca Vaccine Data and Efficacy (thehill.com) 171

whh3 writes: The NIAID issued a statement early Tuesday saying that they had concerns about the data that AstraZeneca included in their Monday-morning release touting the effectiveness of their Covid-19 vaccine. Slashdot reader phalse phace has shared additional information via The Hill. They write: U.S. health officials from the Data and Safety Monitoring Board issued an unusual statement that it was "concerned by information released by AstraZeneca on initial data from its COVID-19 vaccine clinical trial." This comes less than 24 hours after AstraZeneca said its vaccine had an "efficacy of 79% at preventing symptomatic COVID-19 and 100% efficacy at preventing severe disease and hospitalization" and a week after several countries suspended dosing of the vaccine due to concerns of dangerous blood clots.

The Data and Safety Monitoring Board "expressed concern that AstraZeneca may have included outdated information from that trial, which may have provided an incomplete view of the efficacy data." As an oversight committee, the Data and Safety Monitoring Board helps regulate and evaluate clinical trials of new medicines to ensure accuracy and adherence to protocols. In a statement released early Tuesday morning, AstraZeneca said the interim results it announced on Monday were current as of Feb. 17. The latest development could throw a wrench in AstraZeneca's plan to seek the U.S. Food and Drug Administration's emergency use authorization for its vaccine.
Additional coverage: The New York Times
Science

India Battles a Second Covid-19 Wave and Vaccine Skepticism (nytimes.com) 111

An anonymous reader shares a report: India is racing to contain a second wave of the coronavirus, but its vaccination campaign is running into doubters like Akbar Mohamed Patel. A resident of Mumbai's densely populated slum area of Dharavi, Mr. Patel survived a severe bout of the coronavirus in May. The first wave prompted Mumbai officials to seal off his housing complex, confining thousands of people for nearly two months. Still, the current campaign has been marred by a slow initial government rollout, as well as skepticism and apathy from people like Mr. Patel and his neighbors. "On social media we come to know this is all a big game to make money," Mr. Patel said. Of the vaccine, he said, "many things have been hidden." The coronavirus, once seemingly in retreat, is again rippling across India. Confirmed infections have risen to about 31,600 daily from a low of about 9,800 in February. In a recent two-week period, deaths shot up 82 percent.

The outbreak is centered on the state of Maharashtra, home to Mumbai, the country's financial hub. Entire districts of the state have gone back into lockdown. Scientists are investigating whether a new strain found there is more virulent, like variants found in Britain, South Africa and Brazil. Officials are under pressure from Prime Minister Narendra Modi to aggressively ramp up testing and vaccination, especially in Mumbai, to avoid disruptions like last year's dramatic nationwide lockdown and resulting economic recession. "I am very categorical that we should stop it, contain it, just here," said Dr. Rahul Pandit, a critical care physician at a private hospital in Mumbai and a member of the Maharashtra Covid-19 task force. India's vaccination campaign could have global consequences. Last week, Prime Minister Boris Johnson said that an expected drop in Britain's Covid-19 vaccine supplies stemmed from a nearly monthlong delay in delivery of five million doses of the Oxford-AstraZeneca vaccine being manufactured in India. The reasons for the delay are not clear, but the manufacturer, Serum Institute of India, has said shipments will depend in part on domestic Indian needs.

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