Science – Page 70

Top Harvard Cancer researchers accused of scientific fraud; 37 studies affected

Dana Farber, fraud, Photoshop, research, Science, scientific fraud / Kris Guyer / January 22, 2024

Lazy —

Researchers accused of manipulating data images with copy-and-paste.

Beth Mole – Jan 22, 2024 10: 45 pm UTC

Enlarge / The Dana-Farber Cancer Institute in Boston.

The Dana-Farber Cancer Institute, an affiliate of Harvard Medical School, is seeking to retract six scientific studies and correct 31 others that were published by the institute’s top researchers, including its CEO. The researchers are accused of manipulating data images with simple methods, primarily with copy-and-paste in image editing software, such as Adobe Photoshop.

The accusations come from data sleuth Sholto David and colleagues on PubPeer, an online forum for researchers to discuss publications that has frequently served to spot dubious research and potential fraud. On January 2, David posted on his research integrity blog, For Better Science, a long list of potential data manipulation from DFCI researchers. The post highlighted many data figures that appear to contain pixel-for-pixel duplications. The allegedly manipulated images are of data such as Western blots, which are used to detect and visualize the presence of proteins in a complex mixture.

DFCI Research Integrity Officer Barrett Rollins told The Harvard Crimson that David had contacted DFCI with allegations of data manipulation in 57 DFCI-led studies. Rollins said that the institute is “committed to a culture of accountability and integrity,” and that “Every inquiry about research integrity is examined fully.”

The allegations are against: DFCI President and CEO Laurie Glimcher, Executive Vice President and COO William Hahn, Senior Vice President for Experimental Medicine Irene Ghobrial, and Harvard Medical School professor Kenneth Anderson.

The Wall Street Journal noted that Rollins, the integrity officer, is also a co-author on two of the studies. He told the outlet he is recused from decisions involving those studies.

Amid the institute’s internal review, Rollins said the institute identified 38 studies in which DFCI researchers are primarily responsible for potential manipulation. The institute is seeking retraction of six studies and is contacting scientific publishers to correct 31 others, totaling 37 studies. The one remaining study of the 38 is still being reviewed.

Of the remaining 19 studies identified by David, three were cleared of manipulation allegations, and 16 were determined to have had the data in question collected at labs outside of DFCI. Those studies are still under investigation, Rollins told The Harvard Crimson. “Where possible, the heads of all of the other laboratories have been contacted and we will work with them to see that they correct the literature as warranted,” Rollins wrote in a statement.

Despite finding false data and manipulated images, Rollins pressed that it doesn’t necessarily mean that scientific misconduct occurred and the institute has not yet made such a determination. The “presence of image discrepancies in a paper is not evidence of an author’s intent to deceive,” Rollins wrote. “That conclusion can only be drawn after a careful, fact-based examination which is an integral part of our response. Our experience is that errors are often unintentional and do not rise to the level of misconduct.”

The very simple methods used to manipulate the DFCI data are remarkably common among falsified scientific studies, however. Data sleuths have gotten better and better at spotting such lazy manipulations, including copied-and-pasted duplicates that are sometimes rotated and adjusted for size, brightness, and contrast. As Ars recently reported, all journals from the publisher Science now use an AI-powered tool to spot just this kind of image recycling because it is so common.

Top Harvard Cancer researchers accused of scientific fraud; 37 studies affected Read More »

Megalodon wasn’t as chonky as a great white shark, experts say

animals, Biology, extinct animals, megalodon, megaototh shark, paleontology, Science / Kris Guyer / January 22, 2024

Still a pretty impressive size —

Fresh evidence points to megalodon being longer, more slender than previous depictions.

Jennifer Ouellette – Jan 22, 2024 10: 20 pm UTC

These are the kinds of shark teeth discovered in burial sites and other ceremonial remains of the inland Maya communities. From left to right, there's a fossilized megalodon tooth, great white shark tooth, and bull shark tooth. — Enlarge / These are the kinds of shark teeth discovered in burial sites and other ceremonial remains of the inland Maya communities. From left to right, there’s a fossilized megalodon tooth, great white shark tooth, and bull shark tooth.

Antiquity

The megalodon, a giant shark that went extinct some 3.6 million years ago, is famous for its utterly enormous jaws and correspondingly huge teeth. Recent studies have proposed that the megalodon was robust species of shark akin to today’s great white sharks, only three times longer. And just like the great white shark inspired Jaws, the megalodon has also inspired a 1997 novel and a blockbuster film (2018’s The Meg)—not to mention a controversial bit of “docu-fiction” on the Discovery Channel. But now a team of 26 shark experts are challenging the great white shark comparison, arguing that the super-sized creature’s body was more slender and possibly even longer than researchers previously thought in a new paper published in the journal Paleontologia Electronica.

“Our study suggests that the modern great white shark may not necessarily serve as a good modern analogue for assessing at least certain aspects of its biology, including its size,” co-author Kenshu Shimada, a palaeobiologist at DePaul University in Chicago, told The Guardian. “The reality is that we need the discovery of at least one complete megalodon skeleton to be more confident about its true size as well its body form.” Thus far, nobody has found a complete specimen, only fossilized teeth and vertebrae.

As previously reported, the largest shark alive today, reaching up to 20 meters long, is the whale shark, a sedate filter feeder. As recently as 4 million years ago, however, sharks of that scale likely included the fast-moving predator megalodon (formally Otodus megalodon). Due to incomplete fossil data, we’re not entirely sure how large megalodons were and can only make inferences based on some of their living relatives, like the great white and mako sharks.

Thanks to research published last year on its fossilized teeth, we’re now fairly confident that it shared something else with these relatives: it wasn’t entirely cold-blooded and apparently kept its body temperature above that of the surrounding ocean. Most sharks, like most fish, are ectothermic, meaning that their body temperatures match those of the surrounding water. But a handful of species, part of a group termed mackerel sharks, are endothermic: They have a specialized pattern of blood circulation that helps retain some of the heat their muscles produce. This enables them to keep some body parts at a higher temperature than their surroundings. A species called the salmon shark can maintain a body temperature that’s 20° C warmer than the sub-Arctic waters that it occupies.

Megalodon is also a mackerel shark, and some scientists have suggested that it, too, must have been at least partially endothermic to have maintained its growth rates in the varied environments that it inhabited. The 2023 study measured isotope clumping—which can provide an estimate of the temperature at which a material formed—in mastodon teeth. They confirmed that the megalodon samples were consistently warmer, with an average temperature difference of about 7° C compared to cold-blooded samples.

Megalodon wasn’t as chonky as a great white shark, experts say Read More »

Archaeologists discover intact medieval gauntlet at Kyburg Castle

Archaeology, Science / Rejus Almole / January 20, 2024

Did Thanos drop something? —

The team also unearthed fragments of the glove’s companion, worn on the opposite hand.

Jennifer Ouellette – Jan 19, 2024 3: 52 pm UTC

Archaeologists announced this week that they have discovered an intact 14th-century medieval gauntlet during excavations around Switzerland’s Kyburg Castle—a rare find, given that only five other gauntlets from this period have been found in the region to date. It’s remarkably well-preserved, with many design and decorative details clearly visible. The team also unearthed fragments of the glove’s companion, worn on the opposite hand.

The origins of Kyburg Castle date back to around the late 10th century, with the first mention occurring in 1027 under the name Chuigeburg (translation: “cows-fort”). That suggests it was originally used to house livestock. The Holy Roman Emperor Conrad II destroyed that early fortification sometime between 1028 and 1030, but it was rebuilt and became a possession of the counts of Dillingen. It was partially destroyed again in 1079 as Pope Gregory VII and Henry IV (who would later become Holy Roman Emperor) engaged in a bitter conflict over which of them had the power to install bishops, monastery abbots, and even the pope himself (known as the Investiture Controversy).

That conflict didn’t resolve for a good 50 years, but Kyburg Castle endured, and by the 13th century, the counts of Kyburg (descendants of the Dillingen family) were among the most powerful noble families in the Swiss plateau. Kyburg Castle is one of the largest surviving castles in Switzerland, with its existing core dating back to the 13th century. In addition to the tower and great hall, there are several residential and commercial buildings as well as a chapel, all connected by a ring wall that encloses the courtyard. It has belonged to the Canton of Zurich since 1917 and is currently run by the Verein Museum Schloss Kyburg.

During the winter of 2021 and 2022, the archaeologists were excavating the area just southeast of Kyburg Castle in response to the discovery of a medieval weaving cellar, found during the construction of a new house. The cellar had been destroyed by fire sometime in the 14th century, and the team concluded that a blacksmith likely made use of the cellar, since researchers found about 50 metal objects on site: hammers, keys, and projectile points, in particular. But the intact gauntlet and the fragments of its twin were the most exciting and relevant finds.

The use of hand protection in battle dates back to the late 12th century, when the mail sleeves of knights’ mail vests (hauberks) were extended into something akin to a mitten, designed to be worn over a leather glove and including some mail to protect the fingers. Mail gauntlets with separated fingers appeared in the early 14th century, featuring plates that overlapped around finger and thumb joints, although only the thumb plates were articulated. The design evolved again in the late 14th and early 15th centuries to include more articulated plates attached to mail or leather gloves.

The latter is the style of the newly discovered gauntlet. It’s a right-hand glove with four fingers. The individual plates are stacked like scales and held into place with rivets. Additional rivets on the inside were used to attach the plates to the base material (likely leather), and this in turn was sewn onto a fabric finger glove. This is fairly intricate craftsmanship, judging by the still-visible manufacturing and decorative details.

Kyburg Castle will display a copy of the gauntlet as part of its permanent exhibition, along with a reconstruction of the rest of the armor the owner would have worn along with it. The original will be displayed for three weeks this September. In the meantime, archaeologists will set about learning more about who the gauntlet belonged to and hopefully determine why such finds are so rare. It’s possible that such metal objects were melted down and recycled rather than being preserved, but until more such gauntlets are found, it is difficult to reach a definitive conclusion.

Archaeologists discover intact medieval gauntlet at Kyburg Castle Read More »

DeepMind AI rivals the world’s smartest high schoolers at geometry

AI, AlphaGeometry, alphago, AlphaZero, deepmind, Science / Rejus Almole / January 20, 2024

Enlarge / Demis Hassabis, CEO of DeepMind Technologies and developer of AlphaGO, attends the AI Safety Summit at Bletchley Park on November 2, 2023 in Bletchley, England.

A system developed by Google’s DeepMind has set a new record for AI performance on geometry problems. DeepMind’s AlphaGeometry managed to solve 25 of the 30 geometry problems drawn from the International Mathematical Olympiad between 2000 and 2022.

That puts the software ahead of the vast majority of young mathematicians and just shy of IMO gold medalists. DeepMind estimates that the average gold medalist would have solved 26 out of 30 problems. Many view the IMO as the world’s most prestigious math competition for high school students.

“Because language models excel at identifying general patterns and relationships in data, they can quickly predict potentially useful constructs, but often lack the ability to reason rigorously or explain their decisions,” DeepMind writes. To overcome this difficulty, DeepMind paired a language model with a more traditional symbolic deduction engine that performs algebraic and geometric reasoning.

The research was led by Trieu Trinh, a computer scientist who recently earned his PhD from New York University. He was a resident at DeepMind between 2021 and 2023.

Evan Chen, a former Olympiad gold medalist who evaluated some of AlphaGeometry’s output, praised it as “impressive because it’s both verifiable and clean.” Whereas some earlier software generated complex geometry proofs that were hard for human reviewers to understand, the output of AlphaGeometry is similar to what a human mathematician would write.

AlphaGeometry is part of DeepMind’s larger project to improve the reasoning capabilities of large language models by combining them with traditional search algorithms. DeepMind has published several papers in this area over the last year.

How AlphaGeometry works

Let’s start with a simple example shown in the AlphaGeometry paper, which was published by Nature on Wednesday:

The goal is to prove that if a triangle has two equal sides (AB and AC), then the angles opposite those sides will also be equal. We can do this by creating a new point D at the midpoint of the third side of the triangle (BC). It’s easy to show that all three sides of triangle ABD are the same length as the corresponding sides of triangle ACD. And two triangles with equal sides always have equal angles.

Geometry problems from the IMO are much more complex than this toy problem, but fundamentally, they have the same structure. They all start with a geometric figure and some facts about the figure like “side AB is the same length as side AC.” The goal is to generate a sequence of valid inferences that conclude with a given statement like “angle ABC is equal to angle BCA.”

For many years, we’ve had software that can generate lists of valid conclusions that can be drawn from a set of starting assumptions. Simple geometry problems can be solved by “brute force”: mechanically listing every possible fact that can be inferred from the given assumption, then listing every possible inference from those facts, and so on until you reach the desired conclusion.

But this kind of brute-force search isn’t feasible for an IMO-level geometry problem because the search space is too large. Not only do harder problems require longer proofs, but sophisticated proofs often require the introduction of new elements to the initial figure—as with point D in the above proof. Once you allow for these kinds of “auxiliary points,” the space of possible proofs explodes and brute-force methods become impractical.

DeepMind AI rivals the world’s smartest high schoolers at geometry Read More »

Elizabeth Holmes barred from federal health programs for 90 years

Elizabeth Holmes, exclusion, federal health program, fraud, health, HHS, Science / Kris Guyer / January 19, 2024

Excluded —

The former Theranos CEO is barred from receiving payments from federal health program.

Beth Mole – Jan 19, 2024 11: 17 pm UTC

Theranos CEO and founder Elizabeth Holmes.

Elizabeth Holmes—the disgraced and incarcerated founder of the infamous blood-testing startup Theranos—is barred from participating in federal health programs for nine decades, according to an announcement from the health department Friday.

The exclusion means that Holmes is barred from receiving payments from federal health programs for services or products, which significantly restricts her ability to work in the health care sector. It also prevents her from participating in Medicare, Medicaid, and other federal health care programs. With a 90-year term, the exclusion is lifelong for Holmes, who is currently 39.

The exclusion was announced by Inspector General Christi Grimm of the Department of Health and Human Services’ Office of Inspector General.

Holmes is serving an 11-year, three-month sentence for defrauding investors of her blood-testing startup, Theranos, which she founded in 2003. At the time, Holmes claimed to have developed proprietary technology that could perform hundreds of medical tests using just a small drop of blood from a finger prick. The remarkable claim helped her drive the company’s valuation to a stunning $9 billion in 2014, and set up lucrative partnerships. But, in reality, the technology never worked. The company collapsed in 2018, and she was convicted of fraud in 2022.

In today’s announcement, the health department noted that the statutory minimum on exclusions for convictions like Holmes’ is just five years. But other factors are considered when determining the term, including how long the fraud took place, the length of the prison sentence, and the amount of restitution ordered. In addition to her 11-year prison sentence, Holmes was ordered to pay approximately $452,047,200 in restitution, the HHS-OIG noted.

“Accurate and dependable diagnostic testing technology is imperative to our public health infrastructure. False statements related to the reliability of these medical products can endanger the health of patients and sow distrust in our health care system,” Grimm said. “As technology evolves, so do our efforts to safeguard the health and safety of patients, and HHS-OIG will continue to use its exclusion authority to protect the public from bad actors.”

HHS-OIG also excluded former Theranos President Ramesh Balwani from federal health programs for 90 years. Balwani was also convicted of fraud and is serving a nearly 13-year sentence.

Elizabeth Holmes barred from federal health programs for 90 years Read More »

Big Pharma hiked the price of 775 drugs this year so far: Report

brand name drugs, drug pricing, health, merck, mounjaro, Ozempic, Pharmaceutical industry, sanders, Science / Kris Guyer / January 19, 2024

up and up —

Meanwhile, Senate to consider subpoenas to force pharma CEOs testify on prices.

Beth Mole – Jan 19, 2024 9: 58 pm UTC

Pharmaceutical companies have raised the list prices of 775 brand-name drugs so far this year, with a median increase of 4.5 percent, exceeding the rate of inflation, according to an analysis conducted for the Wall Street Journal.

Drugmakers typically raise prices at the start of the year, and Ars reported on January 2 that companies had plans to raise the list prices of more than 500 prescription medications. The updated analysis, carried out by 46brooklyn Research, a nonprofit drug-pricing analytics group, gives a clearer picture of pharmaceutical companies’ activities this month.

High-profile drugs Ozempic (made by Novo Nordisk) and Mounjaro (Eli Lilly), both used for Type II diabetes and weight loss, were among those that saw price increases. Ozempic’s list price went up 3.5 percent to nearly $970 for a month’s supply, while Mounjaro went up 4.5 percent to almost $1,070 a month. The annual inflation rate in the US was 3.4 percent for 2023.

The asthma medication Xolair (Novartis) and the Shingles vaccine Shingrix (GlaxoSmithKline) saw price increases above 7.5 percent, the Wall Street Journal noted. The highest prices were around 10 percent. For some drugs, the single-digit percentage increases can equal hundreds or even thousands of dollars. For instance, the cystic fibrosis treatment Trikafta (Vertex Pharmaceuticals) went up 5.9 percent to $26,546 for a 28-day supply. And the psoriasis therapy Skyrizi (AbbVie) saw an increase of 5.8 percent, bringing the price to $21,017.

Lawmakers’ responses

The list price is typically not the price that people and health insurance plans pay, and pharmaceutical companies say they sometimes don’t make more money from raising list prices. Instead, they argue that the higher list prices allow them to negotiate large discounts and rebates from pharmacy middle managers, whose revenue and dealings are opaque. Drugmakers who spoke with the Wall Street Journal attributed this year’s price hikes to market conditions, inflation, and the value the drugs provide. Overall, the tactics increase the cost of health care.

The hefty hikes come as the federal government is trying to crack down on the high prices of drugs in the US, which pays far more for prescription medications than other high-income countries. Last year, Medicare began, for the first time, negotiating the prices of 10 costly drugs. The negotiations were a provision of the 2022 Inflation Reduction Act. And a provision in 2021’s American Rescue Plan Act now forces drugmakers to pay Medicaid large rebates if their drug price increases outpace inflation.

But, it’s not enough to provide Americans with relief from high drug prices. On Thursday, Stat reported that Senate health committee chair Bernie Sanders (I-Vt) took steps to subpoena pharmaceutical CEOs regarding a Congressional investigation on high drug prices. Sanders invited Johnson & Johnson CEO Joaquin Duato, Merck CEO Robert Davis, and Bristol Myers Squibb CEO Chris Boerner to testify—but only Boerner agreed, and only on the condition that he would not be the only CEO testifying. The trio were invited to a hearing titled “Why Does the United States Pay, By Far, The Highest Prices In The World For Prescription Drugs?,” which was originally scheduled for January 25. Now, Sanders will hold a committee vote on January 31 on whether to issue subpoenas for the CEOs of Johnson & Johnson and Merck. If the committee votes in favor, it will be the first time it has issued a subpoena in more than 40 years.

All three companies have sued the federal government over the new regulations requiring them to negotiate prices with Medicare. J&J and Merck accused Sanders of calling them to testify as retribution for their legal action.

“You have opted not for the most effective way of securing information relevant to the Committee’s important work on drug prices, but for a broad-ranging public spectacle, with witnesses you can question on pending litigation you disagree with,” Merck wrote to Sanders.

Sanders called the two CEOs’ refusal to testify “absolutely unacceptable.”

Big Pharma hiked the price of 775 drugs this year so far: Report Read More »

Study finds bigfoot sightings correlate with black bear populations

bears, bigfoot, crytozoology, Science, zoology / Kris Guyer / January 19, 2024

Bearly believable —

The big conclusion: “If bigfoot is there, it could be a bear.”

John Timmer – Jan 19, 2024 8: 55 pm UTC

A black bear standing on its hind paws surrounded by greenery in a forest with a blurry background — Enlarge / Black bears will frequently stand on their hind legs, which may increase their misidentification.

The idea that North America is home to a completely unknown primate species just doesn’t seem to go away. Years after everyone started walking around with high-quality cameras in their phones, there still haven’t been any clear images of a bigfoot. But that hasn’t stopped a steady flow of purported sightings.

Now, someone named Floe Foxon has followed up on an earlier analysis and checked for factors that could influence the frequency of bigfoot sightings throughout North America. The results suggest that there’s a strong correlation between sightings and the local black bear population—for every 1,000 bears, the frequency of bigfoot sightings goes up by about 4 percent.

Big (foot) data

It’s easy to see how black bears and bigfoot could be mistaken for each other. Despite their name, the bears come in a wide range of colors, from a golden brown through to a deep reddish one, as well as their namesake black. They’re also large animals and will frequently stand on their hind legs to get a better view of their surroundings. They also frequent the forested areas that are supposedly bigfoot’s favored terrain. Foxon even quotes a reported bigfoot sighting as saying that pictures were obtained but, “One of the pictures looks like a bear.”

Earlier work had used data from the Pacific Northwest to show that the presence of bears correlated with the frequency of bigfoot sightings. But Foxon decided to expand the analysis, bringing in the rest of the US and Canada.

The most recent comprehensive, peer-reviewed data on black bear populations dates from 2006, so the analysis was performed using data from that year. Even so, a number of states and provinces had to be excluded. Sadly for Delaware, Hawaii, Illinois, Indiana, Iowa, Kansas, Nebraska, North Dakota and South Dakota, there were no known black bear populations in those states in 2006. And good population numbers weren’t available for Rhode Island, Texas, Wisconsin, Wyoming, Alberta, Newfoundland and Labrador, Northwest Territories, and Nova Scotia. So, while the work is more comprehensive than the Pacific Northwest-only analysis, there were still considerable gaps.

Data for sightings came from the Bigfoot Field Researchers Organization, which maintains a geo-tagged database of reported sightings. National census data was used to determine the human populations in these areas, and estimates of the amount of forested area were also obtained from the Canadian and US governments.

All of these were combined into two different models. In both models, a larger human population was expected to increase the probability of sightings simply due to increased opportunity. Since bigfoot sightings tend to occur in forested areas—and it’s hard to see how a large primate could hide in most other terrains—forests and sightings were also expected to correlate.

Where the bears are

The key difference between the models was whether they included the local black bear population or not. The model with a bear variable provided a much better fit to the data, suggesting that mistaken identity is a factor in bigfoot sightings.

Overall, Foxon found that, with forested areas and the human population taken into account, there’s about one bigfoot sighting for every 5,000 black bears. Each additional 1,000 bears raises the probability of a sighting by about 4 percent. Hence, the conclusion that “if bigfoot is there, it could be a bear.”

That’s not to say bears account for everything. Foxon notes that there are states without a known breeding population of bears that still have bigfoot sightings. And the human population levels could contribute as a source of mistaken identities in addition to raising the opportunity for sightings.

The paper also suggests that this finding could be helpful for bear conservation, as the frequency of bigfoot sightings may provide a proxy measure for the number of black bears present and thus could provide an independent method of tracking population changes.

Journal of Zoology, 2024. DOI: 10.1111/jzo.13148 (About DOIs).

Study finds bigfoot sightings correlate with black bear populations Read More »

Explaining why a black hole produces light when ripping apart a star

astronomy, astrophysics, black holes, Science, tidal disruption / Mike M. / January 17, 2024

Image of a multi-colored curve, with two inset images of actual astronomical objects. — Enlarge / A model of a tidal disruption, along with some observations of one.

Supermassive black holes appear to be present at the core of nearly every galaxy. Every now and again, a star wanders too close to one of these monsters and experiences what’s called a tidal disruption event. The black hole’s gravity rips the star to shreds, resulting in a huge burst of radiation. We’ve observed this happening several times now.

But we don’t entirely know why it happens—”it” specifically referring to the burst of radiation. After all, stars produce radiation through fusion, and the tidal disruption results in the spaghettification of the star, effectively pulling the plug on the fusion reactions. Black holes brighten when they’re feeding on material, but that process doesn’t look like the sudden burst of radiation from a tidal disruption event.

It turns out that we don’t entirely know how the radiation is produced. There are several competing ideas, but we’ve not been able to figure out which one of them fits the data best. However, scientists have taken advantage of an updated software package to model a tidal disruption event and show that their improved model fits our observations pretty well.

Spaghettification simulation

As mentioned above, we’re not entirely sure about the radiation source in tidal disruption events. Yes, they’re big and catastrophic, and so a bit of radiation isn’t much of a surprise. But explaining the details of that radiation—what wavelengths predominate, how quickly its intensity rises and falls, etc.—can tell us something about the physics that dominates these events.

Ideally, software should act as a bridge between the physics of a tidal disruption and our observations of the radiation they produce. If we simulate a realistic disruption and have the physics right, then the software should produce a burst of radiation that is a decent match for our observations of these events. Unfortunately, so far, the software has let us down; to keep things computationally manageable, we’ve had to take a lot of shortcuts that have raised questions about the realism of our simulations.

The new work, done by Elad Steinberg and Nicholas Stone of The Hebrew University, relies on a software package called RICH that can track the motion of fluids (technically called hydrodynamics). And, while a star’s remains aren’t fluid in the sense of the liquids we’re familiar with here on Earth, their behavior is primarily dictated by fluid mechanics. RICH was recently updated to better model radiation emission and absorption by the materials in the fluid, which made it a better fit for modeling tidal disruptions.

The researchers still had to take a few shortcuts to ensure that the computations could be completed in a realistic amount of time. The version of gravity used in the simulation isn’t fully relativistic, and it’s only approximated in the area closest to the black hole. But that sped up computations enough that the researchers could track the remains of the star from spaghettification to the peak of the event’s radiation output, a period of nearly 70 days.

Explaining why a black hole produces light when ripping apart a star Read More »

With fewer pollinators, plants are cutting back on nectar production

Biology, pansies, plant biology, pollen, pollinators, reproduction, Science / Mike M. / January 16, 2024

I can handle this myself —

Fewer pollinators means more self-pollination, less food for bees.

Dhananjay Khadilkar – Jan 16, 2024 5: 13 pm UTC

Image of a field of multi-colored flowers.

In a striking experiment, scientists from the French Centre Nationale de la Recherche Scientifique (CNRS) and the University of Montpellier have observed the impact of selective pressure on a flowering plant. By comparing the pansy flower variety of today that grows in the Paris region to those regrown from the seeds of the same variety collected in the 1990s and 2000s, the researchers have observed notable differences.

According to the study’s co-author, Pierre-Oliver Cheptou, the plant’s evolution over this period has resulted in a 25 percent increase in self-pollination (or selfing) in modern two plants. “We also noticed a 10 percent decrease in the flower size and a 20 percent reduction in the nectar production, which suggests the decrease in rewards for pollinators such as bumblebees,” he said.

To confirm this outcome, Cheptou and his colleagues conducted behavioral tests involving bumblebees “which preferred the ancestor plants,” Cheptou said.

He added that the study showed the impact of pollinators’ decline on the reproductive system in these plants.

When mom and dad are the same plant

Elaborating on the experiment techniques, the study’s lead author, Samson Acoca-Pidolle, said the researchers used “resurrection ecology,” which involved using plant seeds from the 1990s and 2000s that were picked from the fields in the Paris region and stored in fridges in two botanical conservatories. “In 2021, we went to the same fields to collect the seeds of the descendants of the same flowering plant,” he said. For the study, all the plants were cultivated in a greenhouse at the same time of year to ensure consistency.

Cheptou said that to determine the selfing rates of the ancestor and descendant varieties, the team used a classical molecular technique that involved measuring the frequency at which individual plants had stretches of chromosomes with identical versions of genes. This happens often in selfing since the maternal and paternal copies of a chromosome come from the same individual.

According to Acoca-Pidolle, the research team was surprised at the rapidity of the plant’s evolution in the natural environment. “It seems that the pollinators’ decline is already strong, and there is already selective pressure on this species. The other significance of the result is that we are currently observing the breakdown in the plant-pollinator interaction for this species,” he added.

Acoca-Pidolle said the study suggests that the decline of pollinators could become self-reinforcing. “If plants produce less nectar, we can predict that pollinators will have less food and this could increase the pollinator decline,” he said.

Everything is a trade-off

This adaptation may not necessarily turn out to be beneficial for the plant. “It depends on the time scale we are considering this adaptation as an answer to the selective pressure. In the long term, we know that selfing species have a higher extinction rate than out-crossing species,” he said.

Although this study was restricted to a single plant species, Cheptou suspects a similar evolutionary adaptation could be taking place in other species, too. “For plants that can practice at least a little selfing, we should expect this result. But this has to be checked by experiments,” he said.

According to Cheptou, future research should investigate if a similar pattern exists in this plant species elsewhere in Europe and see if a similar adaptation has occurred in other species.

“The other interesting aspect would be to see if plants’ future evolution could be reversible, which will again make them more attractive to the pollinators and practice less selfing,” Acoca-Pidolle said.

New Phytologist, 2023. DOI: 10.1111/nph.19422

With fewer pollinators, plants are cutting back on nectar production Read More »

Getting “forever chemicals” out of drinking water is expensive

drinking water, EPA, PFAS, Science, syndication / Kris Guyer / January 15, 2024

safe to drink —

Can water utilities meet the EPA’s new standard for PFAS?

Charles Schmidt, Undark Magazine – Jan 15, 2024 4: 51 pm UTC

Situated in a former sand and gravel pit just a few hundred feet from the Kennebec River in central Maine, the Riverside Station pumps half a million gallons of fresh groundwater every day. The well station processes water from two of five wells on either side of the river operated by the Greater Augusta Utility District, or GAUD, which supplies drinking water to nearly 6,000 local households. Most of them reside in Maine’s state capital, Augusta, just a few miles to the south. Ordinarily, GAUD prides itself on the quality of its water supply. “You could drink it out of the ground and be perfectly safe,” said Brian Tarbuck, GAUD’s general manager.

But in March 2021, environmental sampling of Riverside well water revealed trace levels of per- and polyfluoroalkyl substances (PFAS), or “forever chemicals,” as they’re better known. The levels at Riverside didn’t exceed Maine’s drinking water standard of 20 parts per trillion (ppt), which was a relief, Tarbuck said. Still, he and his colleagues at the utility were wary. PFAS have been linked to a variety of health problems, and Maine lawmakers at the time were debating an even stricter limit for the chemicals. Tarbuck knew a lower standard was coming someday. The only question was when.

As it turns out, a tougher standard is expected early this year. That’s when the US Environmental Protection Agency is set to finalize an enforceable cap on PFAS in drinking water that will require GAUD and thousands of other utilities around the country to update their treatment methods. The standard, which in regulatory terms is called a maximum contaminant level, or MCL, limits permissible amounts of the two most studied and ubiquitous PFAS compounds—PFOA and PFOS—to just 4 ppt in drinking water each. Roughly equivalent to a single drop in five Olympic-size swimming pools, this is the lowest concentration that current analytical instruments can reliably detect “within specific limits of precision and accuracy during routine laboratory operating conditions,” according to the EPA. Four other PFAS—PFHxS, PFNA, PFBS, and HFPO-DA (otherwise known as GenX Chemicals)—will be regulated by combining their acceptable levels into a single value. Utilities will have three to five years to bring their systems into compliance.

Agency officials estimate that between 3,400 and 6,300 water systems will be affected by the regulation, which is the EPA’s first ever PFAS standard and the first MCL set by the agency for any chemical in drinking water in over 25 years. PFOA and PFOS account for the majority of anticipated exceedances.

GAUD is now gearing up to spend $3 to 5 million on PFAS removal technology, according to Tarbuck, much of which will be passed on to its customers in the form of higher water bills. Nationally, the price tag of meeting the standard could top $37 billion in upfront costs, in addition to $650 million in annual operating expenses, according to the American Water Works Association, or AWWA, a nonprofit lobbying group representing water utilities. That’s far higher than the EPA’s cost estimate of $777 million to $1.2 billion and a significant burden for an industry already contending with other costly priorities, such as boosting cybersecurity and “replacing all those antiquated, leaking big water pipes that transport the water from the treatment plant to the service line” that connects to homes, said Marc Edwards, a professor of civil and environmental engineering at Virginia Tech. Chris Moody, the AWWA’s regulatory technical manager, said most of the money will be spent in the next several years, as utilities race to install PFAS removal systems and other infrastructure needed to meet compliance deadlines.

In proposing the limits, EPA officials said that they had leveraged the latest science to protect the public from PFAS pollution. Environmental groups welcomed the move as long overdue. But the standard has drawn widespread criticism from the water utility industry and some scientists who say that in many places, small drops in PFAS water levels will matter little for exposure or health. “There are other strategies that get us to safer, public health protective approaches to PFAS that don’t involve the really strict standard that EPA is putting forward,” said Ned Calonge, an associate dean for public health practice at the Colorado School of Public Health and chair of a 2022 National Academies of Sciences report on PFAS exposure, testing, and clinical follow-up.

EPA officials estimate that between 3,400 and 6,300 water systems will be affected by the regulation, which is the agency’s first-ever PFAS standard

A key issue, critics say, is that the standard ensnares too many utilities with very small PFAS exceedances. Roughly 98 percent of drinking water utilities in the country, including GAUD, have maximum PFOA and PFOS levels below 10 ppt, according to the AWWA. When the levels are already so low, further reductions of a few parts per trillion “is not going to have much effect on total exposure intake,” wrote Ian Cousins, an environmental chemist at Stockholm University and one of the world’s leading researchers on PFAS exposure, in an email to Undark.

Drinking water is only one among many different pathways by which people can be exposed to PFAS. The chemicals are also in agricultural produce, fish, meat, outdoor soil, household dust, nonstick cookware, cosmetics, fast-food wrappers, stain- and water-resistant fabrics, and other products. Just how much these sources each contribute to PFAS exposure is a subject of ongoing research. But the EPA estimates that Americans get 80 percent of their PFAS intake from sources other than drinking water, and according to Cousins, dietary contributions likely account for most human exposure. The US Food and Drug Administration has required the phase out of some PFAS in food packaging. But “food is contaminated via bioaccumulation in agricultural and marine food chains,” Cousins said. “We cannot clean up our food in the same way that we can add a treatment process to our drinking water.”

Getting “forever chemicals” out of drinking water is expensive Read More »

Daily Telescope: Life on Earth, and maybe in the heavens above, in a single photo

daily telescope, Science, Space / Kris Guyer / January 15, 2024

Life finds a way —

It is fun to contemplate all of the life on display in this image.

Eric Berger – Jan 15, 2024 1: 00 pm UTC

Enlarge / The Milky Way over the sea.

Alfonso Tamés

Welcome to the Daily Telescope. There is a little too much darkness in this world and not enough light, a little too much pseudoscience and not enough science. We’ll let other publications offer you a daily horoscope. At Ars Technica, we’re going to take a different route, finding inspiration from very real images of a universe that is filled with stars and wonder.

Good morning. It’s January 15, and today’s image comes to us from Playa Grande, Mexico.

I realize that some readers may be tiring of seeing the Milky Way Galaxy, but not me! I love photos of our galaxy and so they are regularly featured in the Daily Telescope. However, this photo is truly special, as it highlights not just the heavens above, but one of the wonders here on Earth.

Alfonso Tamés sent me this image, and I can’t get enough of it. The photo showcases both our galaxy and a bit of the Orion Nebula in the sky and bioluminescence in the ocean—that is light being emitted by marine life in the sea. One of the most amazing nights I’ve ever had is kayaking in a bioluminescent bay in Puerto Rico, such an eerie and otherworldly experience.

It is fun to contemplate all of the life on display in this image, both what is known in the ocean and what may exist around all those stars above. Have a great week, everyone.

Source: Alfonso Tamés

Do you want to submit a photo for the Daily Telescope? Reach out and say hello.

Daily Telescope: Life on Earth, and maybe in the heavens above, in a single photo Read More »

CDC reports dips in flu, COVID-19, and RSV—though levels still very high

annual flu shot, CDC, COVID-19, deaths, flu season, health, influenza, influenza-like illness, respiratory viruses, RSV, Science, vaccines / Kris Guyer / January 13, 2024

a break? —

The dips may be due to holiday lulls and CDC is monitoring for post-holiday increase.

Beth Mole – Jan 12, 2024 11: 34 pm UTC

Enlarge / The influenza virus from an image produced from an image taken with transmission electron microscopy. Viral diameter ranges from around 80 to 120 nm.

Key indicators of seasonal flu activity declined in the first week of the year, signaling a possible reprieve from the high levels of respiratory virus transmission this season—but the dip may only be temporary.

On Friday, the Centers for Disease Control and Prevention released its latest flu data for the week ending on January 6. Outpatient visits for influenza-like illnesses (ILI) were down that week, the first decline after weeks of rapid increases. Flu test positivity and hospitalizations were also down slightly.

Enlarge / Percent of outpatient visits for respiratory illnesses by week.

But transmission is still elevated around the country. Fourteen states have ILI activity at the “very high” level in the current data, down from 22 the week before. And 23 states have “high” activity level, up from 19 the week before. (You can see the week-by-week progression of this year’s flu season in the US here.)

The CDC says it is monitoring for “a second period of increased influenza activity that often occurs after the winter holidays.”

Flu isn’t the only virus that seems to be letting up a little in the data, at least for now. COVID-19 data also showed some dips, with the CDC reporting that “Despite test positivity (percentage of tests conducted that were positive), emergency department visits, and hospitalizations remaining elevated nationally, the rates have stabilized, or in some instances decreased, after multiple weeks of continual increase.”

The CDC speculates that some of the declines in indicators could be due to people not seeking medical care during the holidays as they would otherwise. COVID-19 wastewater activity levels remain “very high,” with all regions showing high or increasing levels. The South and Midwest have the highest levels in the latest data, but there are some early indications that rises in the Midwest and Northeast may be slowing down.

Meanwhile, RSV activity remains elevated, though some areas are starting to see declines.

The CDC notes that it’s not too late to get vaccinated against COVID-19, flu, and (for those ages 60 and over) RSV. So far, 21 percent of adults have received the 2023–2024 COVID-19 vaccine, including 41.5 percent of people ages 65 and up. Around 363,000 people have died from COVID-19 in the US since September.

For flu, about 47 percent of adults have received their annual shot, including 74 percent of people ages 65 and up. On Thursday, researchers in Canada published the first estimates of flu vaccine effectiveness this season, finding the current annual shots are 61 percent effective against the most common strain of flu circulating in the US (influenza A(H1N1)pdm09) and 49 percent effective against the less common influenza A(H3N2) and 75 percent effective against influenza B.

The CDC estimates that there have been at least 14 million flu cases, 150,000 hospitalizations, and 9,400 deaths from flu so far this season so far, the agency reported. In the first week of this year, 13 children died of flu, bringing this season’s total to 40.

CDC reports dips in flu, COVID-19, and RSV—though levels still very high Read More »