60-year-old limit to lasers overturned by quantum researchers

A team of Australian quantum theorists has shown how to break a bound that had been believed, for 60 years, to fundamentally limit the coherence of lasers.

The coherence of a laser beam can be thought of as the number of photons (particles of light) emitted consecutively into the beam with the same phase (all waving together). It determines how well it can perform a wide variety of precision tasks, such as controlling all the components of a quantum computer.

Now, in a paper published in Nature Physics, the researchers from Griffith University and Macquarie University have shown that new quantum technologies open the possibility of making this coherence vastly larger than was thought possible.

It 's shown now that  the true limit imposed by quantum mechanics is that the coherence cannot be greater than the fourth power of the number of photons stored in the laser.

 Travis J. Baker et al. The Heisenberg limit for laser coherence, Nature Physics (2020). DOI: 10.1038/s41567-020-01049-3

https://phys.org/news/2020-10-year-old-limit-lasers-overturned-quan...

**'Fireball' meteorite contains pristine extraterrestrial organic compounds

O n the night of January 16, 2018, a fireball meteor streaked across the sky over the Midwest and Ontario before landing on a frozen lake in Michigan. Scientists used weather radar to find where the pieces landed and meteorite hunters were able to collect the meteorite quickly, before its chemical makeup got changed by exposure to liquid water. And, as a new paper in Meteoritics & Planetary Science shows, that gave scientists a glimpse of what space rocks are like when they're still in outer space—including a look at pristine organic compounds that could tell us about the origins of life.

This meteorite is special because it fell onto a frozen lake and was recovered quickly. It was very pristine. Researchers could see the minerals weren't much altered and later found that it contained a rich inventory of extraterrestrial organic compounds. These kinds of organic compounds were likely delivered to the early Earth by meteorites and might have contributed to the ingredients of life.

Scientists aren't sure how the organic (carbon-containing) compounds responsible for life on Earth got here; one theory is that they hitched their way here on meteorites. That doesn't mean that the meteorites themselves contain extraterrestrial life; rather, some of the organic compounds that help make up life might have first formed in an asteroid that later fell to Earth.

As soon as the thing lands, it gets covered with microbes and life from Earth. We have meteorites with lichens growing on them. So the fact that this meteorite was collected so quickly after it fell, and that it landed on ice rather than in the dirt, helped keep it cleaner.

https://phys.org/news/2020-10-fireball-meteorite-pristine-extraterr...

Researchers break magnetic memory speed record

Spintronic devices are attractive alternatives to conventional computer chips, providing digital information storage that is highly energy efficient and also relatively easy to manufacture on a large scale. However, these devices, which rely on magnetic memory, are still hindered by their relatively slow speeds, compared to conventional electronic chips.

Now an international team of researchers has reported a new technique for magnetization switching—the process used to "write" information into magnetic memory—that is nearly 100 times faster than state-of-the-art spintronic devices. The advance could lead to the development of ultrafast magnetic memory for computer chips that would retain data even when there is no power.

In the study, the researchers report using extremely short, 6-picosecond electrical pulses to switch the magnetization of a thin film in a magnetic device with great energy efficiency. A picosecond is one-trillionth of a second.

 Kaushalya Jhuria et al. Spin–orbit torque switching of a ferromagnet with picosecond electrical pulses, Nature Electronics (2020). DOI: 10.1038/s41928-020-00488-3

https://techxplore.com/news/2020-10-magnetic-memory.html?utm_source...

Researchers link poor memory to attention lapses and media multitasking

Scientists are now able to predict whether an individual will remember or forget something based on their neural activity and pupil size.

As we navigate our lives, we have these periods in which we're frustrated because we're not able to bring knowledge to mind, expressing what we know. Fortunately, science now has tools that allow us to explain why an individual, from moment to moment, might fail to remember something stored in their memory.

To monitor attention lapses in relation to memory, 80 study subjects between the ages of 18 to 26 had their pupils measured and their brain activity monitored via an electroencephalogram (EEG) - specifically, the brain waves referred to as posterior alpha power—while performing tasks like recalling or identifying changes to previously studied items.

Increases in alpha power in the back of your skull have been related to attention lapses, mind wandering, distractibility and so forth. Constrictions in pupil diameter—in particular before you do different tasks—are related to failures of performance like slower reaction times and more mind wandering.

This work demonstrates a correlation, not causation. You can't say that heavier media multitasking causes difficulties with sustained attention and memory failures, though we are increasingly learning more about the directions of the interactions. 

one direction that the field as a whole has been heading in is a focus on what happens before learning or, as in this case, before remembering even occurs. That's because memory heavily depends on goal-directed cognition—we essentially need to be ready to remember, have attention engaged and a memory goal in mind—in order to retrieve our memories.

"While it's logical that attention is important for learning and for remembering, an important point here is that the things that happen even before you begin remembering are going to affect whether or not you can actually reactivate a memory that is relevant to your current goal.

conscious awareness of attentiveness, readiness to remember and limiting potential distractions allow individuals to influence their mindsets and alter their surroundings to improve their memory performance."Hacking" memory. While these relatively straightforward strategies can be applied now, the researchers note that there may eventually be targeted attention-training exercises or interventions that people can employ to help them stay engaged. These are referred to as "closed-loop interventions" and are an active area of research.

 advances in measuring attentional states and their impacts on the use of goals to guide remembering also hold promise for a better understanding of disease or health conditions that affect memory.

More information: Memory failure predicted by attention lapsing and media multitasking, Nature (2020). DOI: 10.1038/s41586-020-2870-z , www.nature.com/articles/s41586-020-2870-z

https://medicalxpress.com/news/2020-10-link-poor-memory-attention-l...

Researchers examine the decline in average body temperature among healthy adults over the past two decades

Why human body temperatures are decreasing among healthy adults over the past two decades

In the nearly two centuries since German physician Carl Wunderlich established 98.6°F (37 C) as the standard "normal" body temperature, it has been used by parents and doctors alike as the measure by which fevers—and often the severity of illness—have been assessed.

In more recent years, lower body temperatures have been widely reported in healthy adults. A 2017 study among 35,000 adults in the United Kingdom found average body temperature to be lower (97.9°F / 36.6 C), and a 2019 study showed that the normal body temperature in Americansis about 97.5°F (36.4 C). Several similar reports from around the world have been noticed in recent times.

In less than two decades we're seeing about the same level of decline as that observed in the U.S. over approximately two centuries. Researchers’ analysis is based on a large sample of 18,000 observations of almost 5,500 adults, and adjust for multiple other factors that might affect body temperature, such as ambient temperature and body mass.

Declines might be due to the rise of modern health care and lower rates of lingering mild infections now as compared to the past. It could be that people are in better condition, so their bodies might be working less to fight infection. Or greater access to antibiotics and other treatments means the duration of infection is shorter now than in the past. Consistent with that argument, Researchers found that having a respiratory infection in the early period of the study led to having a higher body temperature than having the same respiratory infection more recently.

It's also possible that greater use of anti-inflammatory drugs like ibuprofen may reduce inflammation, though the researchers found that the temporal decline in body temperature remained even after their analyses accounted for biomarkers of inflammation.

Another possibility is that our bodies don't have to work as hard to regulate internal temperature because of air conditioning in the summer and heating in the winter.

While Tsimane body temperatures do change with time of year and weather patterns, the Tsimane still do not use any advanced technology for helping to regulate their body temperature. They do, however, have more access to clothes and blankets.

The researchers were initially surprised to find no single "magic bullet" that could explain the decline in body temperature. "It's likely a combination of factors—all pointing to improved conditions.

 M. Gurven el al., "Rapidly declining body temperature in a tropical human population," Science Advances (2020). advances.sciencemag.org/lookup … .1126/sciadv.abc6599

https://phys.org/news/2020-10-decline-average-body-temperature-heal...

Judges' decisions in sport focus more on vigour than skill

Judges' decisions are an integral part of combat sports, from boxing and wrestling to mixed martial arts (MMA). However, a new study suggests the rate at which competitors fight is more likely to result in judges awarding victory than the skill with which they attack their opponents.

They analysed almost 550 men's and women's mixed martial arts contests, taking place between February 2019 and March 2020, using data collated for the Ultimate Fighting Championship (UFC).

That data included the percentage of significant strikes landed that land firmly on the target (a measure of skill), the number of strikes attempted per second (a measure of vigour), the outcome of the fight and whether it was determined by knockout or judges' decision.

The results showed that in all fights, winners fought more vigorously than losers but this performance trait was more important for fights resolved via judges' decisions compared with those ending as a result of a knockout or technical knockout.

Fighting skilfully (landing more significant strikes) also increased their chance of winning—with skilful fighting even enhancing the effect of vigour on success—but despite this, the rate of attack was consistently the dominant factor determining success in fights evaluated by judges.

Perceived and actual fighting ability: Determinants of success via decision, knockout or submission in human combat sports, Biology Letters (2020). royalsocietypublishing.org/doi … .1098/rsbl.2020.0443

https://phys.org/news/2020-10-decisions-sport-focus-vigour-skill.ht...

Researchers develop artificial cell on a chip

Researchers have developed a precisely controllable system for mimicking biochemical reaction cascades in cells. Using microfluidic technology, they produce miniature polymeric reaction containers equipped with the desired properties. This 'cell on a chip' is useful not only for studying processes in cells, but also for the development of new synthetic pathways for chemical applications or for biological active substances in medicine.

In order to survive, grow and divide, cells rely on a multitude of different enzymes that catalyze many successive reactions. Given the complexity of processes in living cells, it is impossible to determine when specific enzymes are present at what concentrations and what their optimum proportions are relative to one another. Instead, researchers use smaller, synthetic systems as models in order to study these processes. These synthetic systems simulate the subdivision of living cells into separate compartments.

developed a new strategy for producing these synthetic systems. Writing in the journal Advanced Materials, the researchers describe how they create various synthetic miniature reaction containers, known as vesicles, which—taken as a whole—serve as models of a cell.

"Unlike in the past, this is not based on the self-assembly of vesicles. "Rather, we've developed efficient microfluidic technology in order to produce enzyme-loaded vesicles in a controlled manner." The new method allows the researchers to tweak the size and composition of the different vesicles so that various biochemical reactions can take place inside them without influencing one another—like in the different compartments of a cell.

In order to manufacture the desired vesicles, the scientist feed the various components into tiny channels on a silicon-glass chip. On this chip, all of the microchannels come together at a junction. If the conditions are configured correctly, this arrangement produces an aqueous emulsion of uniformly sized polymer droplets that are formed at the point of intersection.

 Elena C. Santos et al. Combinatorial Strategy for Studying Biochemical Pathways in Double Emulsion Templated Cell‐Sized Compartments, Advanced Materials (2020). DOI: 10.1002/adma.202004804

https://phys.org/news/2020-10-artificial-cell-chip.html?utm_source=...

Physicists circumvent centuries-old theory to cancel magnetic fields

A team of scientists including two physicists has found a way to circumvent a 178-year old theory which means they can effectively cancel magnetic fields at a distance. They are the first to be able to do so in a way which has practical benefits.

The work is hoped to have a wide variety of applications. For example, patients with neurological disorders such as Alzheimer's or Parkinson's might in future receive a more accurate diagnosis. With the ability to cancel out 'noisy' external magnetic fields, doctors using magnetic field scanners will be able to see more accurately what is happening in the brain.

"Earnshaw's Theorem" from 1842 limits the ability to shape magnetic fields. The team were able to calculate an innovative way to circumvent this theory in order to effectively cancel other magnetic fields which can confuse readings in experiments.

Rosa Mach-Batlle et al, Tailoring Magnetic Fields in Inaccessible Regions, Physical Review Letters (2020). DOI: 10.1103/PhysRevLett.125.177204

https://phys.org/news/2020-10-physicists-circumvent-centuries-old-t...

Weak equivalence principle violated in gravitational waves

The Weak equivalence principle (WEP) is a key aspect of classical physics. It states that when particles are in freefall, the trajectories they follow are entirely independent of their masses. However, it is not yet clear whether this property also applies within the more complex field of quantum mechanics. In new research published in EPJ C, James Quach at the University of Adelaide, Australia, proves theoretically that the WEP can be violated by quantum particles in gravitational waves—the ripples in spacetime caused by colossal events such as merging black holes.

James Q. Quach, Fisher information and the weak equivalence principle of a quantum particle in a gravitational wave, The European Physical Journal C (2020). DOI: 10.1140/epjc/s10052-020-08530-6

https://phys.org/news/2020-10-weak-equivalence-principle-violated-g...

Scientists discover 500-meter-tall coral reef in the Great Barrier ...

Scientists have discovered a massive detached coral reef in the Great Barrier Reef–the first to be discovered in over 120 years, Schmidt Ocean Institute announced today. Measuring more than 500m high–taller than the Empire State Building, the Sydney Tower and the Petronas Twin Towers–the reef was discovered by Australian scientists aboard Schmidt Ocean Institute's research vessel Falkor, currently on a 12-month exploration of the ocean surrounding Australia.

Solved: the mystery of how dark matter in galaxies is distributed

The gravitational force in the Universe under which it has evolved from a state almost uniform at the Big Bang until now, when matter is concentrated in galaxies, stars and planets, is provided by what is termed 'dark matter." But in spite of the essential role that this extra material plays, we know almost nothing about its nature, behavior and composition, which is one of the basic problems of modern physics. In a recent article scientists have shown that the dark matter in galaxies follows a 'maximum entropy' distribution, which sheds light on its nature.

To say that the distribution of dark matter is organized according to maximum entropy (which is equivalent to 'maximum disorder' or 'thermodynamic equilibrium') means that it is found in its most probable state. To reach this 'maximum disorder' the dark matter must have had to collide within itself, just as gas molecules do, so as to reach equilibrium in which its density, pressure, and temperature are related. However, we do not know how the dark matter has reached this type of equilibrium.

Unlike the molecules in the air, for example, because gravitational action is weak, dark matter particles ought hardly to collide with one another, so that the mechanism by which they reach equilibrium is a mystery. However if they did collide with one another this would give them a very special nature, which would partly solve the mystery of their origin.

The maximum entropy of dark matter has been detected in dwarf galaxies, which have a higher ratio of dark matter to total matter than have more massive galaxies, so it is easier to see the effect in them. However, the researchers expect that it is general behavior in all types of galaxies.

The study implies that the distribution of matter in thermodynamic equilibrium has a much lower central density that astronomers have assumed for many practical applications, such as in the correct interpretation of gravitational lenses, or when designing experiments to detect dark matter by its self-annihilation.

The central density also is very important for the experiments which try to detect dark matter using its self-annihilation. Two dark matter particles could interact and disappear in a process which is highly improbable, but which would be characteristic of their nature. For two particles to interact they must collide. The probability of this collision depends on the density of the dark matter; the higher the concentration of dark matter, the higher is the probability that the particles will collide.

"For that reason, if the density changes so will the expected rate of production of the self-annihilations, and given that the experiments are designed on the prediction of a given rate, if this rate were very low the experiment is unlikely to yield a positive result," says Sánchez Almeida.

Finally, thermodynamic equilibrium for dark matter could also explain the brightness profile of the galaxies. This brightness falls with distance from the center of a galaxy in a specific way, whose physical origin is unknown, but for which the researchers are working to show that it is the result of an equilibrium with maximum entropy.

Jorge Sánchez Almeida et al, The principle of maximum entropy explains the cores observed in the mass distribution of dwarf galaxies, Astronomy & Astrophysics (2020). DOI: 10.1051/0004-6361/202039190

https://phys.org/news/2020-10-mystery-dark-galaxies.html?utm_source...

Apple developing search engine to compete with Google: report

https://techxplore.com/news/2020-10-apple-google.html?utm_source=nw...

Electronic skin patches could restore lost sensation and detect disease

Researchers across Europe are making rapid progress towards developing elastic membrane patches that mimic the human  either in looks, functionality, or both.

Electronic skin (e-skin) is categorised as an 'electronic wearable' – that is, a smart device worn on, or near, the surface of the skin to extract and analyse information relating to the wearer. A better-known electronic wearable is an activity tracker, which typically senses movement or vibrations to give feedback on a user's performance. More advanced wearables collect data on a person's heart rate and blood pressure.

 E-skins developers' aim is to produce stretchy, robust, flexible membranes that incorporate advanced sensors and have the ability to self-heal. The potential implications for medicine and robotics are immense.

Already in circulation are skin-like membranes that adhere to the surface of the body and detect pressure, strain, slip, force and temperature. Others are being created to recognise biochemical changes that signal disease. A number of projects are working on skins that will envelop robots or human prosthetics, giving these machines and instruments the ability to manipulate objects and perceive their environments with a high degree of tactile sensitivity. And the dream, of course, is to develop an e-skin that can connect with the central nervous system of the wearer (someone who is paralysed, for instance), thereby restoring sensation that has been lost through disease or trauma.

https://cordis.europa.eu/project/id/875586

https://techxplore.com/news/2020-10-electronic-skin-patches-lost-se...

Scientists who talk up their own expertise risk undermining their influence, one of the world's best known science communicators says.

Scientists who talk up their own expertise risk undermining their influence, while they must also “speak persistently” to politicians “based on the science” rather than altering their message in pursuit of impact, according to  Anthony Fauci.

The purpose of your communication is not to impress people about how smart you are. The purpose is to get them to understand what the heck you’re talking about. Scientists sharing podiums with politicians “should never be afraid to tell somebody something that they may not like to hear”, added Dr Fauci, who heads the National Institute of Allergy and Infectious Diseases in Maryland. “One of the traps that some scientists get into is that they like the idea of having impact…and sometimes they might hesitate to say something that is not popular to the politician.
https://www.timeshighereducation.com/news/anthony-fauci-scientists-...

Immuneering: Silencing gene expression to cure complex diseases

Immuneering is applying bioinformatics to forge a new approach to drug discovery, develop transformative medicines and help others make the most of their data.

Rather than focusing on the DNA and proteins involved in a disease, Immuneering focuses on disease-associated gene signaling and expression data. Researchers are trying to cancel out those signals like a pair of headphones blocks out unwanted background noise.
The approach is guided by Immuneering’s decade-plus of experience helping large pharmaceutical companies understand the biological mechanisms behind some of their most successful medicines.

Researchers started noticing some common patterns in terms of how these very successful drugs were working, and eventually they realized they could use these insights to create a platform that would let them identify new medicine. The idea is to not just make existing medicines work better but also to create entirely new medicines that work better than anything that has come before.

In keeping with that idea, Immuneering is currently developing a bold pipeline of drugs aimed at some of the most deadly forms of cancer, in addition to other complex diseases that have proven difficult to treat, like Alzheimer’s. For instance some leading drug candidates target a protein signaling pathway associated with many human cancers. trials will begin in an year in this direction.

It’s the first of what Immuneering hopes will be a number of clinical trials enabled “disease-canceling technology,” which analyzes the gene expression data of diseases and uses computational models to identify small-molecule compounds likely to bind to disease pathways and silence them.
Immuneering uncovered some of the mechanisms behind an early cancer immunotherapy. In another, the workings of Teva Pharmaceuticals’ drug for multiple sclerosis were studied.

Today the drug pipelines focuses around oncology, immune-oncology, and neuroscience. Its disease-canceling technology allows Immuneering to launch new drug programs about twice as fast and with about half the capital as other drug development programs.

As long as scientists have a good gene-expression signature from human patient data for a particular disease, they will find targets and biological insights that let them go after them in new ways. It’s a systematic, quantitative, efficient way to get those biological insights compared to a more traditional process, which involves a lot of trial and error. Therefore , the success rates can be very effective.

https://news.mit.edu/2020/immuneering-gene-expression-1026

https://researchnews.cc/news/3273/Silencing-gene-expression-to-cure...

SOFIA Discovers Water on a Sunlit Surface of the Moon

Cancer cells mediate immune suppression in the brain

Cancer cells mediate immune suppression in the brain
Scientists have long thought that the brain protects itself from an aggressive immune response to keep down inflammation. However, that evolutionary control may work against it when a cancer cell attempts to spread to the brain, researchers have discovered.

In newly published research in the journal Cell, researchers showed that one type of cell important for immunity, called a myeloid cell, can suppress the immune response which has the effect of allowing breast cancer cells to metastasize to the brain to form secondary tumour cells there.

https://news.nd.edu/news/cancer-cells-mediate-immune-suppression-in...

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Better “artificial bone” coating to make implants safer and more effective

Superior coating performance achieved compared to existing clinical products, allowing better artificial bone synthesis and coating on the surface of metal and polymer materials.

Seung‐Hoon Um, et al. Robust Hydroxyapatite Coating by Laser‐Induced Hydrothermal Synthesis, Advanced Functional Materials (2020). DOI: 10.1002/adfm.202005233

https://www.advancedsciencenews.com/better-artificial-bone-coating-...

Would Your Dog Eat You if You Died? Get the Facts.

Directly observing intracellular nanoparticle formation with nano-computed tomography

It is currently challenging to directly observe the formation of intracellular nanostructures in the lab. In a new report, a research team in chemistry, life sciences, medical engineering and science and technology, used a rationally designed small molecule abbreviated NBC-Iod-CBT (short for 4-nitrobenzyl carbamate–Cys(SEt)-Asp-Asp-Phe(iodine)–2-cyano-benzothiazole) and directly observed intracellular nanoparticle formation with nanocomputed tomography (nano-CT).

During the experiments, the glutathione (GSH) reduction and nitroreductase (NTR) cleavage mechanisms caused NBC-Iod-CBT molecules to undergo a click condensation reaction and self-assemble nanoparticles (NPs) as Iod-CBT-NPs. When the team conducted nano-CT imaging of NBC-Iod-CBT treated, nitroreductase-expressing HeLa cells in the lab, they showed the existence of self-assembled Iod-CBT-NPs in their cytoplasm. The new strategy is now published on Science Advances and will assist life scientists and bioengineers to understand the formation mechanisms of intracellular nanostructures.

Miaomiao Zhang et al. Directly observing intracellular nanoparticle formation with nanocomputed tomography, Science Advances (2020). DOI: 10.1126/sciadv.aba3190

Hak Soo Choi et al. Design considerations for tumour-targeted nanoparticles, Nature Nanotechnology (2009). DOI: 10.1038/nnano.2009.314

Xiaohu Gao et al. In vivo cancer targeting and imaging with semiconductor quantum dots, Nature Biotechnology (2004). DOI: 10.1038/nbt994

https://phys.org/news/2020-10-intracellular-nanoparticle-formation-...

New 'epigenetic' clock provides insight into how the human brain ages

While our circadian body clock dictates our preferred rhythm of sleep or wakefulness, a relatively new concept—the epigenetic clock—could inform us about how swiftly we age, and how prone we are to diseases of old age.

People age at different rates, with some individuals developing both characteristics and diseases related to aging earlier in life than others. Understanding more about this so-called 'biological age' could help us learn more about how we can prevent diseases associated with age, such as dementia. Epigenetic markers control the extent to which genes are switched on and off across the different cell-types and tissues that make up a human body. Unlike our genetic code, these epigenetic marks change over time, and these changes can be used to accurately predict biological age from a DNA sample. Now, scientists at the University of Exeter have developed a new epigenetic clock specifically for the human brain. As a result of using human brain tissue samples, the new clock is far more accurate than previous versions, that were based on blood samples or other tissues. The researchers hope that their new clock, published in Brain and funded by Alzheimer's Society, will provide insight into how accelerated aging in the brain might be associated with brain diseases such as Alzheimer's disease and other forms of dementia.

Recalibrating the epigenetic clock: implications for assessing biological age in the human cortex, Brain (2020). academic.oup.com/brain/article … 0.1093/brain/awaa334

https://medicalxpress.com/news/2020-10-epigenetic-clock-insight-hum...

**Identifying biomolecule fragments in ionising radiation

When living cells are bombarded with fast, heavy ions, their interactions with water molecules can produce randomly scattered 'secondary' electrons with a wide range of energies. These electrons can then go on to trigger potentially damaging reactions in nearby biological molecules, producing electrically charged fragments. So far, however, researchers have yet to determine the precise energies at which secondary electrons produce certain fragments. In a new study published in EPJ D, researchers in Japan led by Hidetsugu Tsuchida at Kyoto University define for the first time the precise exact ranges in which positively and negatively charged fragments can be produced.

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**Study shows comets impacted start of life on earth

The Big Bang may have started the universe, but it's likely that littler bangs played a key role in life on Earth, say Albion College Physics Professor Nicolle Zellner and Chemistry Professor Vanessa McCaffrey. They (along with former student Jayden Butler, '17) share their fascinating findings on the interspace dispersal of glycolaldehyde (GLA) in an article recently published by the journal Astrobiology.

CRISPR turns normal body fat into a type that burns energy

Metabolic conditions linked to obesity could be treated by removing fat from a person, turning it into energy-burning “beige fat” using CRISPR gene editing and then implanting the altered fat back into the body, animal studies suggest.

It would be a personalised therapy for metabolic disease

 https://www.newscientist.com/article/2257655-crispr-turns-normal-bo...

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The spooky and dangerous side of black licorice

Black licorice may look and taste like an innocent treat, but this candy has a dark side. On Sept. 23, 2020, it was reported that black licorice was the culprit in the death of a 54-year-old man in Massachusetts. How could this be? Overdosing on licorice sounds more like a twisted tale than a plausible fact.

The unfortunate man who recently succumbed to excessive black licorice consumption is not alone. There are a smattering of similar case reports in medical journals, in which patients experience hypertension crisis, muscle breakdown or even death. Adverse reactions are most frequently seen in people over the age of 40 who are eating far more black licorice than the average person. In addition, they are usually consuming the product for prolonged periods of time. In the most recent case, the Massachusetts man had been eating a bag and a half of black licorice every day for three weeks.

Glycyrrhizin (also called glycyrrhizic acid) is the chemical in black licorice that gives the candy its signature flavor, but it also leads to its toxic effects.

https://theconversation.com/the-spooky-and-dangerous-side-of-black-...

New system uses floor vibrations to detect building occupants

Many buildings, manufacturing sites, shopping malls and other public spaces are equipped with occupant detection systems. These systems generally rely on cameras or occupants’ mobile phones. Such technologies infringe on privacy and may not function in emergencies such as fires. Scientists at ENAC’s Applied Computing and Mechanics Laboratory (IMAC) have developed an alternative approach. By installing sensors in a building’s floor slabs, we can measure the vibrations created by footsteps. That lets us calculate the number of people in the building as well as where they are located and their trajectory. The signals the sensors record can vary considerably depending on the person’s anatomy, walking speed, shoe type, health and mood.

This method uses advanced algorithms – or more specifically, support vector machines – to classify the signals recorded by the sensors. Some interpretation strategies were inspired by the convolutional neural networks often employed in pixel-based image recognition, and can identify the footstep characteristics of specific occupants.

https://techxplore.com/news/2020-10-floor-vibrations-occupants.html...'%20mobile%20phones.

https://researchnews.cc/news/3304/New-system-uses-floor-vibrations-...

A Triple Threat Against Cancer
A three-in-one approach combining immune checkpoint inhibition, tumor microenvironment targeting and chemotherapy drugs could help tackle difficult-to-treat tumors.

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Tube-dwelling anemone toxins have pharmacological potential, mappin...

Researchers based in Brazil and the United States have completed the first-ever mapping exercise to profile the toxins produced by tube-dwelling anemones, or cerianthids, a family of marine animals belonging to the same phylum (Cnidaria) as sea anemones, jellyfish and corals. The analysis revealed that the toxins that can act on the nervous system, cardiovascular system, and cell walls, among other functions, paving the way to the discovery of novel medications.

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Scientists explain the paradox of quantum forces in nanodevices

Researchers from the Peter the Great St. Petersburg Polytechnic University (SPbPU) have proposed a new approach to describe the interaction of metals with electromagnetic fluctuations (i.e., with random bursts of electric and magnetic fields). The obtained results have applications in both fundamental physics, and for creating nanodevices for various purposes. The article was published in the European Physical Journal C.

Explaining dark matter without hypothetical undiscovered particles and without changing physical laws

https://sciencex.com/news/2020-10-dark-hypothetical-undiscovered-pa...

To survive asteroid impact, algae adopted Mixotrophy

Modern relatives of the ancient algae also have chloroplasts, which enable them to use sunlight to make food from carbon dioxide and water. This ability to survive both by feeding on other organisms and through photosynthesis is called mixotrophy. Examples of the few land plants with this ability include Venus flytraps and sundews.

Mixotrophy was both the means of initial survival and then an advantage after the post-asteroid darkness lifted because of the abundant small pretty cells, likely survivor cyanobacteria. Tiny, seemingly harmless ocean plants survived the darkness of the asteroid strike that killed the dinosaurs by learning a ghoulish behaviour—eating other living creatures.

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Vast amounts of debris, soot, and aerosols shot into the atmosphere when an asteroid slammed into Earth 66 million years ago, plunging the planet into darkness, cooling the climate, and acidifying the oceans. Along with the dinosaurs on the land and giant reptiles in the ocean, the dominant species of marine algae were instantly wiped out—except for one rare type.

Researchers found that once the post-asteroid darkness cleared, these mixotrophic algae expanded from coastal shelf areas into the open ocean where they became a dominant life form for the next million years, helping to quickly rebuild the food chain. It also helped that larger creatures who would normally feed on these algae were initially absent in the post-extinction oceans.

Only much later did the algae evolve, losing the ability to eat other creatures and re-establishing themselves to become one of the dominant species of algae in today's ocean.

"Algal plankton turn to hunting to survive and recover from end-Cretaceous impact darkness" Science Advances (2020). advances.sciencemag.org/lookup … .1126/sciadv.abc9123

https://phys.org/news/2020-10-survive-asteroid-impact-algae.html?ut...

Researchers develop a new way to create a spectrum of natural-looking hair colours

We been warned of the risks of dyeing hair at home and in salons. Products used can cause allergies and skin irritation—an estimated 1% of people have an allergy to dye. Furthermore, repeated use of some dyes has been linked to cancer.

But there soon may be a solution for the growing list of salons and hair colour enthusiasts searching for natural alternatives to dyes and cosmetics.

Researchers have developed a new way to create a spectrum of natural-looking hair colours, ranging from blond to black, by using enzymes to catalyze synthetic melanin.

Melanin is an enigmatic and ubiquitous material often found in the form of brown or black pigment. 

In the new process,  researchers dye hair by combining mushroom enzymes with an amino acid, causing a process that mimics reactions that naturally occur in the body. Preliminary studies revealed potential for the coloured layer to persist through several washes.

The research  identifies four key advantages to using synthetic melanin instead of traditional dyes:

• Synthetic melanin avoids the use of ammonia as a base layer.
• The precursors to treating hair with melanin are less toxic.
• The process uses safer, more scalable chemicals.
• There is vast potential in future cosmetic translations of synthetic melanin.

Claudia Battistella et al. Bioinspired Chemoenzymatic Route to Artificial Melanin for Hair Pigmentation, Chemistry of Materials (2020). pubs.acs.org/doi/10.1021/acs.chemmater.0c02790

https://phys.org/news/2020-10-spectrum-natural-looking-hair.html?ut...

Mothers pass on allergies to offspring, preclinical study shows

Mothers can pass allergies to offspring while they are developing in the womb, researchers  reported this week .

The research on mice shows that the key antibody responsible for triggering allergic reactions, immunoglobulin E (IgE), can cross the placenta and enter the fetus. When inside the fetus, the antibody binds to fetal mast cells, a type of immune cell that releases chemicals that trigger allergic reactions, from runny noses to asthma. After birth, newborn mice develop allergic reactions to the same type of allergen as their mothers at the time of first exposure—unlike adult mice, which require two exposures. Studies in the laboratory also showed that maternal IgE can bind to human fetal mast cells, indicating they might cross the placenta in humans in a similar way.

Rasha Msallam et al. Fetal mast cells mediate postnatal allergic responses dependent on maternal IgE, Science (2020). DOI: 10.1126/science.aba0864

https://medicalxpress.com/news/2020-10-mothers-allergies-offspring-...

First night bees recorded foraging in darkness

 A new study has identified two species of bees that have adapted their vision for night-time conditions for the first time.

The study by a team of ecology researchers has observed night time foraging behaviour by a nomiine (Reepenia bituberculata) and masked (Meroglossa gemmata) bee species, with both developing enlarged compound and simple eyes which allow more light to be gathered when compared to their daytime kin.

James B. Dorey et al, Morphometric comparisons and novel observations of diurnal and low-light-foraging bees, Journal of Hymenoptera Research (2020). DOI: 10.3897/jhr.79.57308

https://phys.org/news/2020-10-australian-night-bees-foraging-darkne...

Research shows whipping horses doesn’t make them run faster, straighter or safe

the use of the whip to “encourage” horses to run faster and straighter has been shown to potentially be both painful and dangerous. It was found whips make no difference to horse steering, jockey safety, or even a horse’s speed.

https://theconversation.com/research-shows-whipping-horses-doesnt-m...

Mapping extreme microbes in the Amazon’s Boiling River

Deep in the Peruvian Amazon, biochemist Rosa Vásquez Espinoza investigates the medicinal properties of microbes flowing in a sacred boiling river.

Scientists gravitate towards microbes living in extreme environments, like the Boiling River, due to their medicinal value. 

Extremophiles are not exclusive to the Boiling River. They exist in other extreme environments, like in the hot springs in Yellowstone National Park. But Yellowstone’s hot springs are highly acidic. The Boiling River has a different geochemical profile, and the mineral composition is also constantly changing—which makes the microbial ecology unique.

https://massivesci.com/articles/amazon-boiling-river-peru-microbes-...

GaToroid: revolutionizing the future of cancer treatment?

Hadron therapy is of great interest to the medical community as a pioneering radiation therapy that makes use of charged particles to deliver a highly localized dose to a tumor. Unlike traditional radiotherapy, because it minimizes radiation to any neighboring tissue, it may cause fewer side effects and avoid the generation of secondary tumors.

However, because a hadron is made up of charged particles, a magnetic field is needed to ensure that it goes to exactly the right place in the patient. This requires a complex assembly of magnets in giant machines. It also needs to rotate around the patient with 0.5 mm (5 human hairs!) of precision, making it an incredibly complex piece of engineering. Currently, there are only two facilities in the world, at Heidelberg in Germany where the machine is around 13 meters tall, 25 meters in length and weighing more than 600 tons, and Chiba in Japan, where it is 11 meters tall, 13 meters in length and 250 tons in weight, because it is superconductive.

Enter GaToroid, which aims not just to reduce the size of hadron therapy machines but also their complexity, using toroidal superconducting magnets, the idea of GaToroid is to have a machine that looks like an MRI, so instead of a gigantic rotating magnetic arm that moves around the patient, we have something circular that is in a steady state with the patient inside. This has enabled us to make the machine much smaller. However, unlike an MRI, the patient is not immersed in the magnetic field, but it is confined by the coils around them. The idea is that this technology will make hadron therapy far more accessible as it won’t require machines the size of a four-story building.

https://actu.epfl.ch/news/gatoroid-revolutionizing-the-future-of-ca...

https://researchnews.cc/news/3310/GaToroid--revolutionizing-the-fut...

Paracetamol poisonings up

Paracetamol is the most widely used painkiller in the world. “It is a very safe drug, but only for short-​term pain relief and as long as the daily dosage does not go above the recommended range. For adults, the recommended maximum daily dosage is 4,000 milligrams (4 grams), which equates to a maximum of four of the high-​dose tablets or eight of the lower-​dose tablets. When overdosed, paracetamol can cause severe poisoning, even resulting in liver failure with fatal outcomes or the need for liver transplantation.

One problem with paracetamol is that it is not effective for all patients or against all forms of pain. If the drug doesn’t help to ease someone’s symptoms, they may be tempted to increase the dosage without consulting a medical professional. That’s the real problem. This is also where the size of the tablets comes into play. It’s very easy to exceed the maximum daily dosage by taking just a few extra of the 1,000 milligram tablets, whereas, with the lower-​dose 500 milligram tablets, the risk of accidental overdose isn’t as great.

Experts advocate for a critical review of how the 1,000 milligram tablets are prescribed and dispensed. At the very least, packs of the 1,000 milligram tablets should contain a smaller number of tablets. As evidence grows that paracetamol is not suitable for chronic pain management, there is little need to have pack-​sizes of 40 or 100 tablets.  Physicians should prescribe the lower 500 milligram dose, which can be dose adjusted to reach the 1,000 milligrams by taking two tablets when necessary. This could minimize the risk of accidentally exceeding the daily limit.

By reducing the availability of the high-​dose formulation, experts think that some of the poisoning cases could be avoided. In the meantime, she says pharmacists can help draw attention to the dangers of exceeding the daily maximum when providing these the high-​dose tablets to patients.

https://ethz.ch/en/news-and-events/eth-news/news/2020/10/paracetamo...

https://researchnews.cc/news/3306/Paracetamol-poisonings-up#.X5zxQY...

A color-changing material inspired by chameleon skin

Sci-com: What a link between chocolate and Nobel prizes reveals

https://theconversation.com/what-a-link-between-chocolate-and-nobel...

--

**Mouth Bacteria Have Been Linked to Severe Forms of Inflammatory Bowel Disease

A genetic analysis of more than a dozen strains of one common bacterium, Campylobacter concisus, has uncovered a short sequence of DNA that might explain why this guy is a law-abiding citizen when at home in the mouth, but a potential terrorist in the gut.

"Oral bacteria enter the digestive system every day when we swallow food or saliva. Most of the bacteria are killed by acids in the stomach, but some can survive and colonise in the intestines. The bacteria might not have colonised for long, but the mouth keeps bringing a constant supply of new bacteria – that's the problem.

Generally speaking, many microbes in the genus Campylobacter are bad news for the human digestive system. If you've ever had a gut-wrenching stomach bug that's sent you running for the bathroom while on an overseas holiday, there's a good chance this tiny horror was behind it.

Since such disease-causing species are typically at home in other animals' intestines, we tend to pick them up by consuming contaminated meat or water.

C. concisus isn't quite like its more pathogenic cousins. This species we can call our own, living happily under an ocean of spit in virtually all healthy humans.

But in recent years, medical researchers have suspected C. concisus might not always be the peaceful citizen we'd expected it to be. Bacterial markers associated with the microbe are suspiciously linked with active incidences of the intestinal condition Crohn's disease, for example.

Together with ulcerative colitis, Crohn's falls into a category of IBD characterised by a serious inflammation of the gut wall and surrounding tissue. The result is anything from diarrhoea and discomfort to blood in the stool, agonising pain, and weight loss.

In the cases where drugs or lifestyle changes do little to help, surgical 

intervention can be necessary, making it one serious illness to contend with.

Exactly what sets these inflammatory bowel diseases off in the first place isn't entirely clear. Diet and stress are thought to merely aggravate symptoms, with genetics, medications, and environment all playing a potential role in their development.

https://www.sciencealert.com/your-mouth-bacteria-might-be-behind-se...

The Science of Nerdiness

It’s a neurotransmitter thing

Do you get excited and energized by the possibility of learning something new and complex? Do you get turned on by nuance? Do you get really stimulated by new ideas and imaginative scenarios?

If so, you may have an influx of dopamine in your synapses, but not where we traditionally think of this neurotransmitter flowing.

https://www.scientificamerican.com/article/the-science-of-nerdiness...

Artificial intelligence model detects asymptomatic Covid-19 infections through cellphone-recorded coughs

Asymptomatic people who are infected with Covid-19 exhibit, by definition, no discernible physical symptoms of the disease. They are thus less likely to seek out testing for the virus, and could unknowingly spread the infection to others.

But it seems those who are asymptomatic may not be entirely free of changes wrought by the virus. MIT researchers have now found that people who are asymptomatic may differ from healthy individuals in the way that they cough. These differences are not decipherable to the human ear. But it turns out that they can be picked up by artificial intelligence.

In a paper published recently in the IEEE Journal of Engineering in Medicine and Biology, the team reports on an AI model that distinguishes asymptomatic people from healthy individuals through forced-cough recordings, which people voluntarily submitted through web browsers and devices such as cellphones and laptops.

The researchers trained the model on tens of thousands of samples of coughs, as well as spoken words. When they fed the model new cough recordings, it accurately identified 98.5 percent of coughs from people who were confirmed to have Covid-19, including 100 percent of coughs from asymptomatics — who reported they did not have symptoms but had tested positive for the virus.

https://news.mit.edu/2020/covid-19-cough-cellphone-detection-1029

https://researchnews.cc/news/3340/Artificial-intelligence-model-det...

The pseudo-science of phrenology

https://www.thecourier.co.uk/fp/nostalgia/from-the-archives/1668244...

Insects Play a Key (And Also Icky Role) in Decomposition by Turning Corpses Into Bones

Life after death: How insects rise from the dead and transform corpses into skeletons

While skeletons are universally considered symbols of death, the process of turning a newly dead animal into a bony skeleton relies on an explosion of life that ushers in the process of decomposition. Much of this transformative process is performed by wriggling, scuttling, scurrying insects.

Estimating risk of airborne COVID-19 with mask usage, social distancing

The continued increase in COVID-19 infection around the world has led scientists from many different fields, including biomedicine, epidemiology, virology, fluid dynamics, aerosol physics, and public policy, to study the dynamics of airborne transmission.

Employing basic concepts of fluid dynamics and the known factors in airborne transmission of diseases, the researchers propose the Contagion Airborne Transmission (CAT) inequality model. While not all factors in the CAT inequality model may be known, it can still be used to assess relative risks, since situational risk is proportional to exposure time.

Using the model, the researchers determined protection from transmission increases with physical distancing in an approximately linear proportion.

If you double your distance, you generally double your protection. This kind of scaling or rule can help inform policy."

The scientists also found even simple cloth masks provide significant protection and could reduce the spread of COVID-19.

 Any physical activity that increases the breathing rate and volume of people will increase the risk of transmission. These findings have important implications for the reopening of schools, gyms, or malls.

Rajat Mittal et al, A mathematical framework for estimating risk of airborne transmission of COVID-19 with application to face mask use and social distancing, Physics of Fluids (2020). DOI: 10.1063/5.0025476

https://phys.org/news/2020-10-airborne-covid-mask-usage-social.html...

Mythbusting: Five common misperceptions surrounding the environmental impacts of single-use plastics

Five misperceptions surrounding the environmental impacts of single-use plastic.

• Plastic packaging is the largest contributor to a product's environmental impact. In reality, the product inside the package usually has a much greater environmental impact.
• The environmental impacts of plastics are greater than any other packaging material. Actually, plastic generally has lower overall environmental impacts than single-use glass or metal in most impact categories.
• Reusable products are always better than single-use plastics. Actually, reusable products have lower environmental impacts only when they are reused enough times to offset the materials and energy used to make them.
• Recycling and composting should be the highest priority. Truth be told, the environmental benefits associated with recycling and composting tend to be small when compared with efforts to reduce overall consumption.
• "Zero waste" efforts that eliminate single-use plastics minimize the environmental impacts of an event. In reality, the benefits of diverting waste from the landfill are small. Waste reduction and mindful consumption, including a careful consideration of the types and quantities of products consumed, are far larger factors dictating the environmental impact of an event.

https://phys.org/news/2020-10-mythbusting-common-misperceptions-env...

Five misperceptions surrounding the environmental impacts of single-use plastic, Environmental Science & Technology (2020). pubs.acs.org/doi/10.1021/acs.est.0c05295

Microplastics in groundwater (and our drinking water) present unknown risk

Microplastics (plastics <5mm) and their negative health impacts have been studied in oceans, rivers, and even soils, and scientists are beginning to grapple with the myriad human health impacts their presence might have. One understudied, but critical, link in the cycle is groundwater, which is often a source of drinking water.
While microplastics in groundwater likely affect human health, only a handful of studies have examined the abundance and movement of microplastics in groundwater. This gap means the potential for adverse health effects remains largely unknown.
Microplastics pose multiple physical and chemical risks to the ecosystems where they're present, and those risks are exacerbated by plastics' longevity in natural environments. Since they're plastic, they're very durable which is why plastic is great. But it doesn't degrade easily. Microplastics' ability to linger in their environments for decades or longer likely has cumulative detrimental effects on both the organisms and quality of the ecosystem. Their chemical threat stems largely from their ability to transport harmful compounds on their surfaces; when organisms at the base of the food chain ingest microplastics, they ingest the toxins, too. As larger organisms consume the smaller ones, the toxins can build up (a process called bioaccumulation), eventually resulting in responses like organ dysfunction, genetic mutation, or death. Cave ecosystems are known for being super fragile to begin with. All the cave organisms—salamanders, blind fish—are sensitive, so any contaminants that are introduced could damage those ecosystems.
Groundwater can stay in the same aquifer for tens to hundreds of years, or even longer. Combining that long residence time with plastics' resistance to degradation means that those chemical effects could effectively build up in the water and in any organisms within it, increasing the likelihood of toxic bioaccumulation. Together, these could result in long-term contamination of water sources with poorly-understood health effects and ecosystem damage.
Researchers found that while microplastics do increase in groundwater during a flood event, there's also a second peak in microplastics after the flooding has begun to wane. Their explanation is that there are two sources of microplastics for groundwater: those that are already in the subsurface, and those that are newly delivered from the surface. Finding so much plastic later on in the flood, thinking that it could be coming from the surface... is important to understand the sourcing of microplastics in the groundwater. Knowing where the plastic is coming from could help mitigate future contamination.

Paper 23-1: Quantifying microplastic debris sourcing and transport for a karst aquifer
Abstract Link: gsa.confex.com/gsa/2020AM/meet … app.cgi/Paper/355066

https://phys.org/news/2020-10-microplastics-groundwater-unknown.htm...

**How to figure out what you don't know

Increasingly, biologists are turning to computational modeling to make sense of complex systems. In neuroscience, researchers are adapting the kinds of algorithms used to forecast the weather or filter spam from your email to seek insight into how the brain's neural networks process information.

Testing various computational models of the nervous system, researchers have found that just because a model can make good predictions about data does not mean it reflects the underlying logic of the biological system it represents. Relying on such models without carefully evaluating their validity could lead to wrong conclusions about how the actual system works.

By building and comparing several models of neural signaling, Engel and Genkin found that good predictive power does not necessarily indicate that a model is a good representation of real neural networks. They found that the best models were instead those that were most consistent across multiple datasets. This approach won't necessarily work for all situations, however, and biologists may need alternative methods of evaluating their models. Most importantly, Genkin said, "We shouldn't take anything for granted. We should check every assumption we have."

Genkin, M., Engel, T.A. Moving beyond generalization to accurate interpretation of flexible models. Nat Mach Intell (2020). doi.org/10.1038/s42256-020-00242-6

https://techxplore.com/news/2020-10-figure-dont.html?utm_source=nwl...

Researchers Decipher The Secret Ingredients of Ancient Egyptian Ink

An analysis of 12 ancient papyrus fragments has revealed some surprising details about how the Egyptians mixed their red and black ink – findings which could give us a lot more insight into how the earliest writers managed to get their words down on the page.

Ancient Egyptians were using inks to write at least as far back as 3200 BCE. However, the samples studied in this case were dated to 100-200 CE and originally collected from the famous Tebtunis temple library – the only large-scale institutional library known to have survived from the period.

Using a variety of synchrotron radiation techniques, including the use of high-powered X-rays to analyse microscopic samples, the researchers revealed the elemental, molecular, and structural composition of the inks in unprecedented detail.

The red inks, typically used to highlight headings, instructions, or keywords, were most likely coloured by the natural pigment ochre, the researchers say – traces of iron, aluminium, and hematite point to this being the case.

More intriguing was the discovery of lead-based compounds in both the black and the red inks, without any of the traditional lead-based pigments used for colouring. This suggests the lead was added for technical purposes. Lead-based driers prevent the binder from spreading too much, when ink or paint is applied on the surface of paper or papyrus.

As well as explaining how the ancient Egyptians kept their papyrus smudge-free, it also suggests some pretty specialised ink manufacturing techniques. The fact that the lead was not added as a pigment but as a drier infers that the ink had quite a complex recipe and could not be made by just anyone.

Insights into the composition of ancient Egyptian red and black inks on papyri achieved by synchrotron-based microanalyses

https://www.pnas.org/content/early/2020/10/22/2004534117

https://www.sciencealert.com/chemical-analysis-has-revealed-the-adv...

The Mystery of The Platypus Deepens With The Discovery of Its Biofluorescent Fur

Scientists are seeing the  platypus in a whole new light. Under an ultraviolet lamp, this bizarre-looking creature appears even more peculiar than normal, glowing a soft, greenish-blue hue instead of the typical brown we're used to seeing.

https://www.sciencealert.com/the-australian-platypus-is-the-latest-...

Doubts over a ‘possible sign of life’ on Venus show how science works

Further searches for reported hints of phosphine have been turning up empty

It was one of those “big, if true” stories. In September, scientists reported that Venus’ atmosphere seems to be laced with phosphine, a possible sign of life.

Now there’s increasing emphasis on the “if.” As scientists take fresh looks at the data behind the Venus announcement, and add other datasets to the mix, the original claim of inexplicable amounts of phosphine is being called into doubt. And that’s a good thing, many scientists say.

It’s exactly how science should work.

On September 14, astronomer Jane Greaves of Cardiff University in Wales and colleagues reported that they had seen signs of phosphine in Venus’ clouds using two different telescopes (SN: 9/14/20). The phosphine seemed to be too abundant to exist without some kind of source replenishing it. That source could be strange microbes living in the clouds, or some weird unknown Venusian chemistry, the team said.

Greaves and colleagues first spotted phosphine with the James Clerk Maxwell Telescope in Hawaii and followed up with the powerful ALMA telescope array in Chile. But those ALMA data, and particularly the way they were handled, are now being called into question.

The key Venus observations were spectra, or plots of the light coming from the planet in a range of wavelengths. Different molecules block or absorb light at specific wavelengths, so searching for dips in a spectrum can reveal the chemicals in a planet’s atmosphere.

Phosphine showed up as a dip in Venus’ spectrum at about 1.12 millimeters, a wavelength of light that the molecule was thought to be absorbing. If Venus’ spectrum could be drawn as a straight line across all wavelengths of light, phosphine would make a deep valley at that wavelength.

But real data are never that easy to read. In real life, other sources — from Earth’s atmosphere to the inner workings of the telescope itself — introduce wiggles, or “noise,” into that nice straight line. The bigger the wiggles, the less scientists believe that the dips represent interesting molecules. Any particular dip might instead be just a random, extra-large wiggle.

That problem gets even worse when looking at a bright object such as Venus with a powerful telescope like ALMA

“The reason those bumps and wiggles are here at all is because of the intrinsic brightness of Venus, which makes it difficult to get a reliable measurement,” Cordiner says. “You could think of it as being dazzled by a bright light: If there’s a bright light in your vision, then your ability to pick out fainter details becomes diminished.”

So astronomers do a few different things to smooth out the data and let real signals shine through.

https://www.sciencenews.org/article/venus-phosphine-possible-sign-l...

I.A.G. Snellen et al. Re-analysis of the 267-GHz ALMA observations of Venus: No statistic.... arXiv:2010.09761. Posted October 19, 2020.

T. Encrenaz et al. A stringent upper limit on the PH₃ abundance at the cloud top of Venus. Astronomy & Astrophysics, in press, 2020. doi:10.1051/0004-6361/202039559.

**Nylon finally takes its place as a piezoelectric textile

Saleem Anwar et al. Piezoelectric Nylon‐11 Fibers for Electronic Textiles, Energy Harvesting and Sensing, Advanced Functional Materials (2020). DOI: 10.1002/adfm.202004326

https://phys.org/news/2020-10-nylon-piezoelectric-textile.html?utm_...

New insight into how brain neurons influence choices

When you are faced with a choice—say, whether to have ice cream or chocolate cake for dessert—sets of brain cells just above your eyes fire as you weigh your options. Animal studies have shown that each option activates a distinct set of neurons in the brain. The more enticing the offer, the faster the corresponding neurons fire.

Now, a study in monkeys by researchers has shown that the activity of these neurons encodes the value of the options and determines the final decision. In the experiments, researchers let animals choose between different juice flavours. By changing the neurons' activity, the researchers changed how appealing the monkeys found each option, leading the animals to make different choices.

A detailed understanding of how options are valued and choices are made in the brain will help us understand how decision-making goes wrong in people with conditions such as addiction, eating disorders, depression and schizophrenia.

Values encoded in orbitofrontal cortex are causally related to economic choices, Nature (2020). DOI: 10.1038/s41586-020-2880-x , www.nature.com/articles/s41586-020-2880-x

https://medicalxpress.com/news/2020-11-insight-brain-neurons-choice...