In January 1861 John Tyndall, a physicist at London’s Royal Institution, submitted a paper to the Philosophical Transactions of the Royal Society of London. The paper bore the title “On the absorption and radiation of heat by gases and vapours, and on the physical connexion of radiation, absorption, and conduction.” After testing the heat-retaining properties of several gases, Tyndall had concluded that some were capable of trapping heat, and thus he became one of the first physicists to recognize and describe that basis for the greenhouse effect. A month after its submission, the paper was read aloud at a meeting of the society, and several months after that, a revised version of the paper was in print.

That path from submission to revision and publication will sound familiar to modern scientists. However, Tyndall’s experience with the Philosophical Transactions—in particular, with its refereeing system—was quite different from what authors experience today. Tracing “On the absorption and radiation of heat” through the Royal Society’s editorial process highlights how one of the world’s most established refereeing systems worked in the 1860s. Rather than relying on anonymous referee reports to improve their papers, authors engaged in extensive personal exchanges with their reviewers. Such a collegial approach gradually lost favor but recently has undergone something of a resurgence.

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We probably cannot slow the rate at which we get older, because of biological constraints, an unprecedented study of lifespan statistics in human and non-human primates has confirmed.  

The study set out to test the ‘invariant rate of ageing’ hypothesis, which says that a species has a relatively fixed rate of ageing from adulthood. An international collaboration of scientists from 14 different countries, including José Manuel Aburto from Oxford’s Leverhulme Centre for Demographic Science, analysed age-specific birth and death data spanning centuries and continents. 

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Post-traumatic stress disorder (PTSD) presents a major public health problem for which currently available treatments are modestly effective. We report the findings of a randomized, double-blind, placebo-controlled, multi-site phase 3 clinical trial (NCT03537014) to test the efficacy and safety of 3,4-methylenedioxymethamphetamine (MDMA)-assisted therapy for the treatment of patients with severe PTSD, including those with common comorbidities such as dissociation, depression, a history of alcohol and substance use disorders, and childhood trauma. After psychiatric medication washout, participants (n = 90) were randomized 1:1 to receive manualized therapy with MDMA or with placebo, combined with three preparatory and nine integrative therapy sessions. PTSD symptoms, measured with the Clinician-Administered PTSD Scale for DSM-5 (CAPS-5, the primary endpoint), and functional impairment, measured with the Sheehan Disability Scale (SDS, the secondary endpoint) were assessed at baseline and at 2 months after the last experimental session. Adverse events and suicidality were tracked throughout the study. MDMA was found to induce significant and robust attenuation in CAPS-5 score compared with placebo (P < 0.0001, d = 0.91) and to significantly decrease the SDS total score (P = 0.0116, d = 0.43). The mean change in CAPS-5 scores in participants completing treatment was −24.4 (s.d. 11.6) in the MDMA group and −13.9 (s.d. 11.5) in the placebo group. MDMA did not induce adverse events of abuse potential, suicidality or QT prolongation. These data indicate that, compared with manualized therapy with inactive placebo, MDMA-assisted therapy is highly efficacious in individuals with severe PTSD, and treatment is safe and well-tolerated, even in those with comorbidities. We conclude that MDMA-assisted therapy represents a potential breakthrough treatment that merits expedited clinical evaluation.

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Jun 14

As its name suggests, dark matter – material which makes up about 85% of the mass in the universe – emits no light, eluding easy detection. Its properties, too, remain fairly obscure. Now, a theoretical particle physicist have shown how theories positing the existence a new type of force could help explain dark matter’s properties.

A subatomic particle has been found to switch between matter and antimatter, according to Oxford physicists analyzing data from the Large Hadron Collider. It turns out that an unfathomably tiny weight difference between two particles could have saved the universe from annihilation soon after it began.

If you could peer into a particle physicist’s daydream, you might spy a vision of a giant lunar particle accelerator. Now, researchers have calculated what such an enormous, hypothetical machine could achieve.

A particle collider encircling the moon could reach an energy of 14 quadrillion electron volts, physicists report June 6 at arXiv.org. That’s about 1,000 times the energy of the world’s biggest particle accelerator, the Large Hadron Collider, or LHC, at CERN near Geneva.

It’s not an idea anyone expects will become reality anytime soon, says particle physicist James Beacham of Duke University. Instead, he and physicist Frank Zimmermann of CERN considered the possibility “primarily for fun.” But physicists of future generations could potentially build a collider on the moon, Beacham says.

Such a fantastical machine would probably be buried under the moon’s surface to avoid wild temperature swings, the researchers say, and could be powered by a ring of solar panels around the moon.

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From the biggest bridges to the smallest medical implants, sensors are everywhere, and for good reason: The ability to sense and monitor changes before they become problems can be both cost-saving and life-saving.

To better address these potential threats, the Intelligent Structural Monitoring and Response Testing (iSMaRT) Lab at the University of Pittsburgh Swanson School of Engineering has designed a new class of materials that are both sensing mediums and nanogenerators, and are poised to revolutionize the multifunctional material technology big and small.

The research, recently published in Nano Energy, describes a new metamaterial system that acts as its own sensor, recording and relaying important information about the pressure and stresses on its structure. The so-called “self-aware metamaterial” generates its own power and can be used for a wide array of sensing and monitoring applications.

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The visible surface of the sun, or the photosphere, is around 6,000°C. But a few thousand kilometers above it—a small distance when we consider the size of the sun—the solar atmosphere, also called the corona, is hundreds of times hotter, reaching a million degrees celsius or higher.

This spike in temperature, despite the increased distance from the sun’s main energy source, has been observed in most stars, and represents a fundamental puzzle that astrophysicists have mulled over for decades.

In 1942, the Swedish scientist Hannes Alfvén proposed an explanation. He theorized that magnetized waves of plasma could carry huge amounts of energy along the sun’s magnetic field from its interior to the corona, bypassing the photosphere before exploding with heat in the sun’s upper atmosphere.

The theory had been tentatively accepted—but we still needed proof, in the form of empirical observation, that these waves existed. Our recent study has finally achieved this, validating Alfvén’s 80 year-old theory and taking us a step closer to harnessing this high-energy phenomenon here on Earth.

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May 29

As part of preparing for an experiment aboard the International Space Station, researchers explored new ways to culture living heart cells for microgravity research. They found that cryopreservation, a process of storing cells at -80°C, makes it easier to transport these cells to the orbiting lab, providing more flexibility in launch and operations schedules. The process could benefit other biological research in space and on Earth.

The investigation, MVP Cell-03, cultured heart precursor cells on the space station to study how microgravity affects the number of cells produced and how many of them survive. These precursor cells have potential for use in disease modeling, drug development, and regenerative medicine, such as using cultured heart cells to replenish those damaged or lost due to cardiac disease.

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A prominent French microbiologist has filed a criminal complaint against a world-renowned research-integrity specialist after she publicly flagged concerns about his published work, including papers suggesting that the drug hydroxychloroquine was effective at treating COVID-19, a claim that has now been refuted.

The complaint was filed on 29 April to a prosecutor in Marseille, France, by a lawyer acting on behalf of Didier Raoult, along with his colleague structural biologist Eric Chabriere, both at the city’s Hospital-University Institute Mediterranean Infection (IHU). It accuses Elisabeth Bik — a microbiologist turned research integrity consultant, based in California — of aggravated moral harassment, attempted blackmail and attempted extortion.

Bik — whose work scrutinizing images in research papers has earned her a worldwide following and has led to more than 170 retractions — denies these allegations, and says that her comments about the pair’s work are standard scientific critiques.

More than 1,000 scientists have rallied to support her in an open letter that claims the case could have a “chilling effect” on scholarly criticism.

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May 28

The speed of light may not necessarily be constant. Light travelling through a plasma can appear to move at speeds both slower and faster than what we refer to as “the speed of light” – 299,792,458 metres per second – without breaking any laws of physics.

Clément Goyon at Lawrence Livermore National Laboratory in California and his colleagues accomplished this using a pair of lasers fired into a jet of hydrogen and …

Microfluidic chips speed up biological and chemical experiments. Researchers made them more efficient by using cleverly designed ‘traffic circles’ to direct the flow of fluids.

A few days ago, millions of tons of super-heated gas shot off from the surface of the sun and hurtled 90 million miles toward Earth.

The eruption, called a coronal mass ejection, wasn’t particularly powerful on the space-weather scale, but when it hit the Earth’s magnetic field it triggered the strongest geomagnetic storm seen for years. There wasn’t much disruption this time—few people probably even knew it happened—but it served as a reminder the sun has woken from a yearslong slumber.

While invisible and harmless to anyone on the Earth’s surface, the geomagnetic waves unleashed by solar storms can cripple power grids, jam radio communications, bathe airline crews in dangerous levels of radiation and knock critical satellites off kilter. The sun began a new 11-year cycle last year and as it reaches its peak in 2025 the specter of powerful space weather creating havoc for humans grows, threatening chaos in a world that has become ever more reliant on technology since the last big storms hit 17 years ago. A recent study suggested hardening the grid could lead to $27 billion worth of benefits to the U.S. power industry.

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A pair of researchers at the University of Kent has found that tardigrades are able to survive impacts at speeds of up to 825 meters per second. In their paper published in the journal Astrobiology, Alejandra Traspas and Mark Burchell describe experiments they conducted that involved firing canisters containing tardigrades at high speeds at sand targets.

Tardigrades are tiny eight-legged animals, on the order of 0.1 centimeter in length, of the phylum Tardigrada—they have been given the name “water bear” due to their appearance. Tardigrades have made the news in recent years due to their hardiness. They were the first known animal to survive the rigors of outer space; they are able to go without water for up to 10 years; they can survive extreme pressures and temperatures (including boiling water) and levels of UV radiation that are lethal to most other animals. To achieve these feats, the tiny creatures curl up into a ball and enter a sleep-like state. In this new effort, the researchers wanted to know if they could also survive high-speed impacts.

To find out, the research pair obtained 20 tardigrade specimens and put them in a deep freeze to induce their sleep-like state. They then placed them in groups of two or three into thin cylinders filled with water. The cylinders were then placed inside of a larger cylinder that served as an ammunition shell for a two-stage light gas gun. The gun was placed inside of a vacuum chamber where its shell was fired at a target made of sand. Shots were fired from the gun at different speeds to see what impact each would have on the passenger tardigrades.

The researchers found that the tardigrades shot from the gun at speeds up to 825 meters per second could be resuscitated after removal from the cylinder. Those experiencing higher-speed impacts were torn apart and did not survive.

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Astronomers have known that galaxies across the universe are behaving badly. Some are spinning too fast, while others are just way too hot and still others glommed into super structures too quickly.

But they don’t know why. Perhaps some new hidden particle, like dark matter, could explain the weirdness. Or perhaps gravity is acting on these coalescing clusters of stars in a way scientists hadn’t expected.

For decades, astronomers have debated the possibilities. While most astronomers believe that dark matter exists, some still think that we need to modify our theory of gravity. However, new research has found a critical flaw in modified gravity theories: They allow for effects to occur without causes and for information to travel faster than the speed of light. This is bad … for modified gravity.

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In a ground-breaking study, Swedish scientists have shown that people can detect nano-scale wrinkles while running their fingers upon a seemingly smooth surface. The findings could lead such advances as touch screens for the visually impaired and other products.

The findings were, to say the least, shocking: A researcher in New Zealand claimed that Google searches about violence against women soared during the early months of the Covid-19 pandemic — raising the prospect that quarantines were leading to a surge in intimate partner violence and similar crimes. 

Shocking, yes, but now retracted because the methodology of the study was “catastrophically wrong,” in words of some critics. 

The paper, “COVID-19, suicide, and femicide: Rapid Research using Google search phrases,” was written by Katerina Standish, of the University of Otago’s National Centre for Peace and Conflict Studies and appeared online in January 2021 in the Journal of General Psychology.  

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Papers in leading psychology, economic and science journals that fail to replicate and therefore are less likely to be true are often the most cited papers in academic research, according to a new study by the University of California San Diego’s Rady School of Management.

Published in Science Advances, the paper explores the ongoing “replication crisis” in which researchers have discovered that many findings in the fields of social sciences and medicine don’t hold up when other researchers try to repeat the experiments.

The paper reveals that findings from studies that cannot be verified when the experiments are repeated have a bigger influence over time. The unreliable research tends to be cited as if the results were true long after the publication failed to replicate.

“We also know that experts can predict well which papers will be replicated,” write the authors Marta Serra-Garcia, assistant professor of economics and strategy at the Rady School and Uri Gneezy, professor of behavioral economics also at the Rady School. “Given this prediction, we ask ‘why are non-replicable papers accepted for publication in the first place?’”

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In 2018, Cornell researchers built a high-powered detector that, in combination with an algorithm-driven process called ptychography, set a world record by tripling the resolution of a state-of-the-art electron microscope.

As successful as it was, that approach had a weakness. It only worked with ultrathin samples that were a few atoms thick. Anything thicker would cause the electrons to scatter in ways that could not be disentangled.

Now a team, again led by David Muller, the Samuel B. Eckert Professor of Engineering, has bested its own record by a factor of two with an electron microscope pixel array detector (EMPAD) that incorporates even more sophisticated 3D reconstruction algorithms.

The resolution is so fine-tuned, the only blurring that remains is the thermal jiggling of the atoms themselves.

The group’s paper, “Electron Ptychography Achieves Atomic-Resolution Limits Set by Lattice Vibrations,” published May 20 in Science. The paper’s lead author is postdoctoral researcher Zhen Chen.

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There’s some really interesting CRISPR news out today, and it’s likely to be a forerunner of much more news to come. A research team has demonstrated what looks like robust, long-lasting effects in a primate model after one injection of the CRISPR enzymatic machinery. There have been plenty of rodent reports on various forms of CRISPR, and there are some human trials underway, but these is the first primate numbers that I’m aware of.

The gene they chose to inactivate is PCSK9, which has been a hot topic in drug discovery for some years now. It’s a target validated by several converging lines of evidence from the human population (see the “History” section of that first link). People with overactive PCSK9 have high LDL lipoproteins and cholesterol, and people with mutations that make it inactive have extremely low LDL and seem to be protected from a lot of cardiovascular disease. There are several drugs and drug candidates out there targeting the protein, as well there might be.

It’s a good proof-of-concept, then, because we know exactly what the effects of turning down the expression of active PCSK9 should look like. It’s also got the major advantage of being mostly a liver target – as I’ve mentioned several times  on the blog already, many therapies aimed at gene editing or RNA manipulation have a pharmacokinetic complication. The formulations used to get such agents intact into the body (and in a form that they can penetrate cells) tend to get combed out pretty thoroughly by the liver – which after all, is (among other things) in the business of policing the bloodstream for weird, unrecognized stuff that is then targeted for demolition by hepatocytes. Your entire bloodstream goes sluicing through the liver constantly; you’re not going to able to dodge it if your therapy is out there in the circulation. It happens to our small-molecule drugs all the time: hepatic “first pass” metabolism is almost always a factor to reckon with.

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May 20

In the early days of research on black holes, before they even had that name, physicists did not yet know if these bizarre objects existed in the real world. They might have been a quirk of the complicated math used in the then still young general theory of relativity, which describes gravity. Over the years, though, evidence has accumulated that black holes are very real and even exist right here in our galaxy.

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Created on Jun 17, 2020
By @gurlic
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