Young mice transfused with blood from old mice became fatigued faster and ran shorter distances

A team of researchers from Korea University College of Medicine, the University of California and the Buck Institute for Research on Aging reports that transfusing young mice with blood from older mice makes them grow fatigued and unable to run long distances. The study is published in the journal Nature Metabolism. In 2005, a team of researchers at the University of California stitched pairs of old/young mice together to learn more about the aging process—in that effort, the mice were conjoined; they shared not only blood, but some organs. Testing of the older mice showed that the infusion of younger blood resulted in the reversal of some signs of aging. In this new effort, the researchers tested the process in reverse without resorting to conjoining. The work involved transfusing blood from an aged, two-year-old mouse into mice that were just three months old every day for a week, and then studying the young mice to measure the impact. Putting the mice on a treadmill and getting them to run showed that the young mice became fatigued faster and were not able to run as far as a control group (young mice transfused with blood from other young mice.) The young mice transfused with the blood of older mice showed markers for aging of the liver and kidney damage. The researchers also ran the experiment in reverse, giving old mice young blood, which resulted in reductions in fibrosis and lipids—and also fatigue. There was also an increase in endurance. The researchers suggest that it is likely that cells in the blood of older mice held a senescence-associated secretory phenotype, leading to muscle weakness, tissue damage and other signs of aging in the transfused younger mice. They suggest it also seems possible that cells in the blood from the older mice had ceased reproducing and were having an impact on the younger cells. The researchers also took an indirect approach to testing whether similar results might be observed in humans—they placed cells taken from an older person into plasma from a younger person. Six days later, they found biomarkers of aging.

Ok Hee Jeon et al, Systemic induction of senescence in young mice after single heterochronic blood exchange, Nature Metabolism (2022). DOI: 10.1038/s42255-022-00609-6

Pre-fertilization DNA transfer to avoid mitochondrial disease inheritance appears safe

Transferring the nuclear genome from one egg into the cytoplasm of a donor egg is a strategy to enable women carrying mutations in their mitochondrial DNA to have healthy babies. A new study  published August 16 in the open-access journal PLOS Biology, uses multiple "omics" techniques to show that this strategy, called spindle transfer, is likely to be safe, with little evidence of genetic or functional difference between the resulting embryos and healthy control in vitro fertilization (IVF) embryos. The results are likely to spur further adoption of spindle transfer for IVF when there is a risk of mitochondrial disease.

Mitochondria, the energy powerhouses of the cell, contain their own DNA, mutations in which can cause a variety of inherited diseases, including metabolic, muscular, and neurologic disorders. In human reproduction, only maternal mitochondria, contained in the egg, are inherited. To interrupt that inheritance, techniques have been developed to place parental nuclear DNA into cytoplasm from donor cells carrying healthy mitochondria, either just before fertilization (spindle transfer), or just after (pronuclear transfer).

The "spindle" refers to the division apparatus that holds the nuclear chromosomes in suspension until fertilization. During spindle transfer, the maternal spindle is removed from an unfertilized egg and placed into a donor egg that has had its own spindle removed. (Pronuclear transfer removes the pronucleus, containing both egg and sperm DNA, and places it in a donor embryo whose pronucleus has been removed.) Spindle transfer has been used clinically, but there remain questions about its safety.

To shed light on this question, the authors performed three different types of analyses on single cells from 23 blastocysts following spindle transfer and compared them to 23 control IVF blastocysts. (The blastocyst is the multicellular ball that forms about 5 or 6 days after fertilization, ready for implantation into the uterine wall.) They found no difference in DNA copy number, a measure of genomic integrity, between spindle transfer and control blastocysts. RNA expression profiles were also similar between the two blastocyst types, regardless of which layer of the blastocyst the cells were taken from.

The authors did find a small but significant reduction in the level of DNA demethylation in spindle transfer blastocysts in one layer, the trophectoderm, though not in two other layers. DNA demethylation is one of the processes used to increase gene expression during development, and their analysis suggested that the reduction was evidence of a slight delay in the process, rather than a permanent inability to upregulate the affected genes. It is quite possible that after the blastocyst stage, the spindle transfer embryos can catch up to complete DNA demethylation before implantation.

The researchers concluded that the spindle transfer seems generally safe and does not severely disturb embryonic development. However, given the limitation of the study, more dimensions and larger-scale evaluations are still needed to determine whether this technique can be applied to a wider set of clinical trials.

Single-cell multiomics analyses of spindle-transferred human embryos suggest a mostly normal embryonic development, PLoS Biology (2022). DOI: 10.1371/journal.pbio.3001741

**

Adults who, as children, had half their brain removed still able to score well with face and word recognition

A team of researchers at Carnegie Mellon University's Department of Psychology and Neuroscience Institute has found that adults who had a hemispherectomy as a child scored surprisingly well on face and word recognition tests. Their paper is posted on the bioRxiv preprint server. In epilepsy, abnormal brain activity results in chronic seizures. Some people respond well to medication and others due not; for example, some people experience seizures so often that they become incapacitating. Some young patients in these circumstances are given the option of undergoing a hemispherectomy, the complete removal of the left or right hemisphere of the brain. Prior research has shown that these procedures, when done at a very young age, allow most patients to retain their IQ and their ability to communicate and live relatively normal lives. In sharp contrast, damage to either hemisphere, much less removal of one or the other in adults, leads to severe symptoms or death. In this new effort, the researchers sought to learn more about the cognitive abilities of adults who had undergone a hemispherectomy. Forty subjects were shown grayscale pictures of human faces without hair for 750 milliseconds, followed by a pause of 150 milliseconds. Then another face was shown for 150 milliseconds after which the volunteer reported whether it was the same face or not. The whole process was then repeated several times with different faces. The researchers then repeated the entire exercise but used simple, four-letter words. The researchers expected that those volunteers who had only their right hemisphere would do well at face recognition but not as well at word recognition, since the right hemisphere is generally used to process images while the left hemisphere processes words; they expected the opposite results for those who still had just their left hemisphere. Instead, the researchers found that both groups performed nearly equally well and both were on average 86% accurate on the tests compared to a control group consisting of people who had not undergone an hemispherectomy, with average 96% accuracy. The researchers also conducted a nearly identical experiment in which the faces and words were shown off to the left or right; both groups still did surprisingly well—but there was one interesting difference. In comparing their results with the control group, those who had undergone a hemispherectomy did as well as the control group in identifying images or words in two instances—when a word was placed on the left side, or a face on the right.

Michael C. Granovetter et al, With Childhood Hemispherectomy, One Hemisphere Can Support—But is Suboptimal for—Word and Face Recognition (2020). DOI: 10.1101/2020.11.06.371823

Modern pesticides damage the brain of bees so they can't move in a straight line

The challenge to let people walk back and forth in a straight line isn't just used by police to test if drivers are intoxicated: it's also used by neurologists to diagnose neurological disorders like ataxia, where parts of the brain that coordinate movement are impaired. Now, researchers use an insect version of this challenge to show for the first time that modern pesticides damage the nervous system of honeybees so that it becomes hard for them to walk in a straight line. The results are published in Frontiers in Insect Science.

The commonly used insecticides like sulfoxaflor and the neonicotinoid imidacloprid can profoundly impair the visually guided behavior of honeybees. New research results are reason for concern because the ability of bees to respond appropriately to visual information is crucial for their flight and navigation, and thus their survival.

The results add to what the Food and Agriculture Organization of the United Nations and the World Health Organization have called the "rapidly growing body of evidence [which] strongly suggests that the existing levels of environmental contamination [from neonicotinoid pesticides] are causing large-scale adverse effects on bees and other beneficial insects."

The researchers also show with molecular techniques that pesticide-exposed bees tended to have elevated proportion of dead cells in parts of the brain's optic lobes, important for processing visual input. Likewise, key genes for detoxification were dysregulated after exposure.

Rachel H. Parkinson et al, Honeybee optomotor behaviour is impaired by chronic exposure to insecticides, Frontiers in Insect Science (2022). DOI: 10.3389/finsc.2022.936826

'Forever chemicals' destroyed by simple new method

PFAS, a group of manufactured chemicals commonly used since the 1940s, are called "forever chemicals" for a reason. Bacteria can't eat them; fire can't incinerate them; and water can't dilute them. And, if these toxic chemicals are buried, they leach into surrounding soil, becoming a persistent problem for generations to come.

Now chemists have done the seemingly impossible. Using low temperatures and inexpensive, common reagents, the research team developed a process that causes two major classes of PFAS compounds to fall apart, leaving behind only benign end products. The simple technique potentially could be a powerful solution for finally disposing of these harmful chemicals, which are linked to many dangerous health effects in humans, livestock and the environment.

Even just a tiny, tiny amount of PFAS causes negative health effects, and it does not break down. We can't just wait out this problem.

The secret to PFAS's indestructibility lies in its chemical bonds. PFAS contains many carbon-fluorine bonds, which are the strongest bonds in organic chemistry. As the most electronegative element in the periodic table, fluorine wants electrons, and badly. Carbon, on the other hand, is more willing to give up its electrons.

"When you have that kind of difference between two atoms—and they are roughly the same size, which carbon and fluorine are—that's the recipe for a really strong bond.

Scientists now  found a weakness. PFAS contains a long tail of unyielding carbon-fluorine bonds. But at one end of the molecule, there is a charged group that often contains charged oxygen atoms. Researchers targeted this head group by heating the PFAS in dimethyl sulfoxide—an unusual solvent for PFAS destruction—with sodium hydroxide, a common reagent. The process decapitated the head group, leaving behind a reactive tail.

That triggered all these reactions, and it started spitting out fluorine atoms from these compounds to form fluoride, which is the safest form of fluorine.

After discovering the PFAS degradation conditions, researchers also discovered that the fluorinated pollutants fall apart by different processes than generally assumed. A simulation showed that PFAS actually falls apart two or three carbons at a time—a discovery that matched the researchers' experiments. By understanding these pathways, researchers can confirm that only benign products remain. This new knowledge also could help guide further improvements to the method.

Brittany Trang et al, Low-temperature mineralization of perfluorocarboxylic acids, Science (2022). DOI: 10.1126/science.abm8868. www.science.org/doi/10.1126/science.abm8868

Swarms of microrobots could be solution to unblocking medical devices in body

Swarms of microrobots injected into the human body could unblock internal medical devices and avoid the need for further surgery, according to new research .

The study is the first-time scientists have developed magnetic microrobotics to remove deposits in shunts—common internal medical devices used to treat a variety of conditions by draining excess fluid from organs.

Shunts are prone to malfunctioning, often caused by blockages due to a build-up of sediment. The sediment not only narrows and obstructs liquid passing through the shunt, but it also affects the shunt's flexibility. This leads to patients needing repeated, invasive surgeries throughout their lives either to replace the shunt or use a catheter to remove the blockage.

However, this new research  has shown there could be a wireless, non-invasive alternative to clearing the blockage in a shunt. It has shown that a swarm of hundreds of microrobots—made of nano size magnetic nanoparticles—injected into the shunt could remove the sediment instead.

Once the magnetic microrobots are injected into the shunt they can be moved along the tube to the affected area using a magnetic field, generated by a powerful magnet on the body's surface. The swarm of microrobots can then be moved so they scrape away the sediment, clearing the tube.

"The non-invasive nature of this method is a considerable advantage to existing methods as it will potentially eliminate the risk of surgery and a surgery-related infection, thereby decreasing recovery time.

With each microrobot smaller than the width of a human hair, once the swarm has done its job, it can either be guided to the stomach via a magnetic field or bodily fluid, so they leave the body naturally. Because the microrobots have very high biocompatibility they will not cause toxicity.

The research also found a direct relation between the strength of the magnetic field and the success of scraping away the sediment in the shunt.

This is the first proof-of-concept experiment using microswarms for opening a blockage in a shunt.

A. Moghanizadeh et al, A novel non-invasive intervention for removing occlusions from shunts using an abrading magnetic microswarm, IEEE Transactions on Biomedical Engineering (2022). DOI: 10.1109/TBME.2022.3192807

Turning to the laws of physics to study how cells move

Scientists have long been concerned with trying to understand how cells move, for example in pursuit of new ways to control the spread of cancer. The field of biology continues to illuminate the infinitely complex processes by which collections of cells communicate, adapt, and organize along biochemical pathways.

Turning to the laws of physics, researchers have taken a fresh look at how cells move, revealing similarities between the behaviour of cell tissue and the simplest water droplets. They have taken a different perspective on how cell motion is determined by the properties of the tissues they're in rather than how they act individually.

Published in Physical Review Letters, the researchers’ initial experiments used mechanical techniques to measure the surface tension of a simple "ball" of cell tissue to reveal similarities with the thermo-dynamic properties of water droplets, but with noticeable differences.

With a water droplet the surface tension is constant and doesn't change with droplet size.

However, the scientists found that in the case of a "droplet" of cancer cells surface tension was size dependent—the smaller the tissue the higher the surface tension, and the higher the pressure within the tissue.

Next, they applied a surface tension gradient to show that cells within the tissue moved rapidly and collectively, much like the way the surface of water moves when detergent is added. Their findings were published in Physical Review Fluids.

This so called "Marangoni" effect occurs when the forces at the surface of a tissue drive the motion of cells inside.

To complete the puzzle, the scientists allowed the tissue to adhere to a surface, mimicking the way a tumor grows and spreads. Cells emerged from the ball of tissue like water droplets "wetting" a receptive—or hydrophilic—surface. In some conditions, the wetting increased the internal pressure of the tissue, helping to push cells out.

Published today in Physical Review X, these findings cast new light on the degree to which cells "migrate" or whether pressure from surface tension promotes cell movement.

This new work shows that the bulk properties of tissue, including the surface tension and pressure, matter when it comes to the ability of cells to migrate out of a model tumor.

M. S. Yousafzai et al, Active Regulation of Pressure and Volume Defines an Energetic Constraint on the Size of Cell Aggregates, Physical Review Letters (2022). DOI: 10.1103/PhysRevLett.128.048103

Vikrant Yadav et al, Gradients in solid surface tension drive Marangoni-like motions in cell aggregates, Physical Review Fluids (2022). DOI: 10.1103/PhysRevFluids.7.L031101

Muhammad Sulaiman Yousafzai et al, Cell-Matrix Elastocapillary Interactions Drive Pressure-Based Wetting of Cell Aggregates, Physical Review X (2022). DOI: 10.1103/PhysRevX.12.031027

Can a human with a spinal cord injury walk and run? Discovering clues with neuromorphic technology

 An international research team  has succeeded in recovering muscle movements in a model of paralyzed mice through organic artificial nerves. The result was published in Nature Biomedical Engineering.

The nerves, which are essential for life activities as well as having a significant impact on quality of life, are easily damaged by various causes such as physical injury, genetic causes, secondary complications, and aging. In addition, once nerves are damaged they are difficult to reconstruct, and some or all their bodily functions are permanently lost due to poor bio-signaling.

Among the various methods for rehabilitation in patients with neurological damage, Functional Electrical Stimulation (FES), which is currently actively used in clinical practice, uses computer-controlled signals. Through this setup, electrical stimulation is applied to muscles that are no longer arbitrarily controllable in patients with neuropathy to induce muscle contraction, resulting in functionally useful movements in the biological body even though they are confined in a specific space. However, this conventional approach has limitations that are not suitable for long-term use in patients' daily lives because they involve complex digital circuits and computers for signal processing to stimulate muscles, consuming a lot of energy and poor biocompatibility in the process.

To solve the problem, the research team succeeded in controlling the leg movement of mice only with artificial nerves without a complex and bulky external computer using stretchable, low-power organic nanowire neurormorphic devices that emulate the structure and function of bio nerve fibers. The stretchable artificial nerve consists of a strain sensor that simulates a proprioceptor which detects muscle movements, an organic artificial synapse that simulates a biological synapse, and a hydrogel electrode for transmitting signals to the leg muscles.

The researchers adjusted the movement of the mouse legs and the contraction force of the muscles according to the firing frequency of the action potential transmitted to the artificial synapse with a principle similar to that of the biological nerve, and the artificial synapse implements smoother and more natural leg movements than the usual FES.

In addition, the artificial proprioceptor detects the leg movement of the mouse and gives real-time feedback to the artificial synapse to prevent muscle damage due to excessive leg movement.

The researchers succeeded in allowing a paralyzed mouse to kick the ball or walk and run on the treadmill. Furthermore, the research team showed the applicability of artificial nerves in the future for voluntary movement by sampling pre-recorded signals from the motor cortexes of moving animals and moved the legs of mice through artificial synapses.

The researchers discovered a new application feasibility in the field of neuromorphic technology, which is attracting attention as a next-generation computing device by emulating the behavior of a biological neural network.

https://www.nature.com/articles/s41551-022-00918-x

https://www.eurekalert.org/news-releases/961673

How the brain gathers threat cues and turns them into fear

Scientists have uncovered a molecular pathway that distills threatening sights, sounds and smells into a single message: Be afraid. A molecule called CGRP enables neurons in two separate areas of the brain to bundle threatening sensory cues into a unified signal, tag it as negative and convey it to the amygdala, which translates the signal into fear.

The research, published in Cell Reports on August 16, 2022, may lead to new therapies for fear-related disorders such as post-traumatic stress disorder (PTSD) or hypersensitivity disorders such as autism, migraines and fibromyalgia.

The brain pathway researchers now discovered works like a central alarm system. The CGRP neurons are activated by negative sensory cues from all five senses—sight, sound, taste, smell and touch. Identifying new threat pathways provides insights into treating fear-related disorders.

Most external threats involve multisensory cues, such as the heat, smoke and smell of a wildfire. Previous research showed that different pathways independently relay sound, sight, and touch threat cues to multiple brain areas. A single pathway that integrates all these cues would be beneficial to survival, but no one had ever found such a pathway.

Previous research also showed that the amygdala, which initiates behavioral responses and forms fear memories to environmental and emotional stimuli, receives heavy input from brain regions that are laden with a chemical associated with aversion, the neuropeptide CGRP (calcitonin gene-related peptide).

Based on these two pools of research,  researchers now proposed that CGRP neurons, found especially in subregions of the thalamus and the brainstem, relay multisensory threat information to the amygdala. These circuits may both generate appropriate behavioral responses and help form aversive memories of threat cues.

The researchers conducted several experiments to test their hypotheses. They recorded CGRP neuron activity using single-cell calcium imaging while presenting mice with multisensory threat cues, enabling the researchers to pinpoint which sensory modality involved which sets of neurons. They determined the path the signals took after leaving the thalamus and brainstem using different colored fluorescent proteins. And they conducted behavioral tests to gauge memory and fear.

Taken together, their findings show that two distinct populations of CGRP neurons—one in the thalamus, one in the brainstem—project to nonoverlapping areas of the amygdala, forming two distinct circuits. Both populations encode threatening sights, sounds, smells, tastes and touches by communicating with local brain networks. Finally, they discovered that both circuits are necessary for forming aversive memories—the kind that tell you, "Stay away."

While mice were used in this study, the same brain regions also abundantly express CGRP in humans. This suggests that the circuits reported here may also be involved in threat perception-related psychiatric disorders.

https://www.cell.com/cell-reports/fulltext/S2211-1247(22)01039-7?_returnURL=https%3A%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS2211124722010397%3Fshowall%3Dtrue

Non-nutritive sweeteners affect human microbiomes and can alter glycemic responses

Since the late 1800s non-nutritive sweeteners have promised to deliver all the sweetness of sugar with none of the calories. They have long been believed to have no effect on the human body, but researchers publishing in the journal Cell on August 19 challenge this notion by finding that these sugar substitutes are not inert, and, in fact, some can alter human consumers' microbiomes in a way that can change their blood sugar levels.

In 2014 researchers found that non-nutritive sweeteners affected the microbiomes of mice in ways that could impact their glycemic responses. They were interested in whether these results would also be found in humans.

To address this important question, the researchers  carefully screened over 1,300 individuals for those who strictly avoid non-nutritive sweeteners in their day-to-day lives, and identified a cohort of 120 individuals. These participants were broken into six groups: two controls and four who ingested well below the FDA daily allowances of either aspartame, saccharin, stevia, or sucralose.

In subjects consuming the non-nutritive sweeteners, scientists could identify very distinct changes in the composition and function of gut microbes, and the molecules they secret into peripheral blood. This seemed to suggest that gut microbes in the human body are rather responsive to each of these sweeteners.

When they looked at consumers of non-nutritive sweeteners as groups, they found that two of the non-nutritive sweeteners, saccharin and sucralose, significantly impacted glucose tolerance in healthy adults. Interestingly, changes in the microbes were highly correlated with the alterations noted in people's glycemic responses.

To establish causation, the researchers transferred microbial samples from the study subjects to germ-free mice—mice that have been raised in completely sterile conditions and have no microbiome of their own.

The results were quite striking. In all of the non-nutritive sweetener groups, but in none of the controls, when the researchers transferred into these sterile mice the microbiome of the top responder individuals collected at a time point in which they were consuming the respective non-nutritive sweeteners, the recipient mice developed glycemic alterations that very significantly mirrored those of the donor individuals. In contrast, the bottom responders' microbiomes were mostly unable to elicit such glycemic responses. These results suggest that the microbiome changes in response to human consumption of non-nutritive sweetener may, at times, induce glycemic changes in consumers in a highly personalized manner.

The effects of the sweeteners will vary person to person because of the incredibly unique composition of our microbiome.

 Eran Elinav, Personalized microbiome-driven effects of non-nutritive sweeteners on human glucose tolerance, Cell (2022). DOI: 10.1016/j.cell.2022.07.016. www.cell.com/cell/fulltext/S0092-8674(22)00919-9

How Quinine Fights Malaria

Researchers discover a material that can learn like the brain

Researchers have discovered that Vanadium Dioxide (VO₂), a compound used in electronics, is capable of "remembering" the entire history of previous external stimuli. This is the first material to be identified as possessing this property, although there could be others.

A PhD student made a chance discovery during his research on phase transitions in Vanadium Dioxide (VO₂). VO₂ has an insulating phase when relaxed at room temperature, and undergoes a steep insulator-to-metal transition at 68 °C, where its lattice structure changes. Classically, VO₂ exhibits a volatile memory: "the material reverts back to the insulating state right after removing the excitation" . For his thesis, he set out to discover how long it takes for VO₂ to transition from one state to another. But his research led him down a different path: after taking hundreds of measurements, he observed a memory effect in the material's structure.

In his experiments, the student applied an electric current  to a sample of VO₂. The current moved across the material, following a path until it exited on the other side. As the current heated up the sample, it caused the VO₂ to change state. And once the current had passed, the material returned to its initial state.

He then applied a second current pulse to the material, and saw that the time it took to change state was directly linked to the history of the material. The VO₂ seemed to 'remember' the first phase transition and anticipate the next. The researchers didn't expect to see this kind of memory effect, and it has nothing to do with electronic states but rather with the physical structure of the material. It's a novel discovery: no other material behaves in this way.

The researchers went on to find that VO₂ is capable of remembering its most recent external stimulus for up to three hours. The memory effect could in fact persist for several days, but we don't currently have the instruments needed to measure that.

The research team's discovery is important because the memory effect they observed is an innate property of the material itself. Engineers rely on memory to perform calculations of all kinds, and materials that could enhance the calculation process by offering greater capacity, speed and miniaturization are in high demand. VO₂ ticks all three of these boxes. What's more, its continuous, structural memory sets it apart from conventional materials that store data as binary information dependent on the manipulation of electronic states.

The researchers performed a host of measurements to arrive at their findings. They also corroborated their results by applying the new method to different materials at other laboratories around the world. This discovery replicates well what happens in the brain, as VO₂ switches act just like neurons.

Mohammad Samizadeh Nikoo, Electrical control of glass-like dynamics in vanadium dioxide for data storage and processing, Nature Electronics (2022). DOI: 10.1038/s41928-022-00812-z. www.nature.com/articles/s41928-022-00812-z

Your Next Wooden Chair Could Arrive Flat, Then Dry Into a 3D Shape

Study shows 90% of marine species at risk of extinction by 2100 if greenhouse gas emissions are not curbed

An international team of researchers has found that approximately 90% of all marine life on Earth will be at risk of extinction by 2100 if greenhouse gas emissions are not curbed. In their paper published in the journal Nature Climate Change, the group outlines their study of thousands of marine species and how greenhouse gas emissions might impact them in the future.

Greenhouse gas emissions impact the world's climate in two ways. They raise the temperature of the atmosphere (and by extension, Earth's surfaces and bodies of water) by holding in heat, and in the case of CO₂ emissions, they make water more acidic, like carbonated soft drinks. And as emissions continue to be pumped into the atmosphere despite dire warnings from scientists around the world, more research is being conducted to learn about its possible impact. In this new effort, the researchers took a broad look at the impact of greenhouse gas emissions on ocean life.

The work involved estimating the impact of certain levels of greenhouse gas emissions on marine life in the future. They looked specifically at 25,000 species, including fish, bacteria, plants and protozoans living in the top 100 meters of the world's oceans. They found that under the worst scenario, in which emissions lead to global atmospheric temperature increases of 3 to 5 degrees Celsius, approximately 90% of all marine life will disappear. They also found that if emissions are cut to the extent outlined by the Paris Climate Agreement, which would keep global temperature increases to below 2 degrees Celsius, then the risk of extinction would be reduced by approximately 98%.

The researchers also found that larger top predators are more at risk than smaller predators, as are fish species  in areas where they are heavily fished by humans. Those at lowest risk, on the other hand, include small, short-lived species. Notably, Earth has not seen a die-off as great as these projections since the Great Dying 252 million years ago.

Daniel G. Boyce et al, A climate risk index for marine life, Nature Climate Change (2022). DOI: 10.1038/s41558-022-01437-y

Experiment on YouTube reveals potential to 'inoculate' users against misinformation

Fact-checkers can only rebut a fraction of the falsehoods circulating online. We need to teach people to recognize the misinformation playbook, so they understand when they are being misled.

https://phys.org/news/2022-08-youtube-reveals-potential-inoculate-m...

Here's what a black hole sounds like, according to NASA.

Data Sonification: Black Hole at the Center of the Perseus Galaxy Cluster (X-ray)

New research on the risks of lead exposure from bullets used in big game hunting

The lead in some bullets used for hunting deer, moose, and elk is toxic to the humans who eat the harvested meat and to scavenger animals that feast on remains left in the field.

Physicists entangle more than a dozen photons efficiently

.Physicists  have managed to entangle more than a dozen photons efficiently and in a defined way. They are thus creating a basis for a new type of quantum computer. 

The phenomena of the quantum world, which often seem bizarre from the perspective of the common everyday world, have long since found their way into technology. For example, entanglement: a quantum-physical connection between particles that links them in a strange way over arbitrarily long distances. It can be used, for example, in a quantum computer—a computing machine that, unlike a conventional computer, can perform numerous mathematical operations simultaneously. However, in order to use a quantum computer profitably, a large number of entangled particles must work together. They are the basic elements for calculations, so-called qubits.

Photons, the particles of light, are particularly well suited for this because they are robust by nature and easy to manipulate. Researchers  have now succeeded in taking an important step towards making photons usable for technological applications such as quantum computing: For the first time, a research team generated up to 14 entangled photons in a defined way and with high efficiency.

The trick to this experiment was that they used a single atom to emit the photons and interweave them in a very specific way. To do this, the researchers placed a rubidium atom at the center of an optical cavity—a kind of echo chamber for electromagnetic waves. With laser light of a certain frequency, the state of the atom could be precisely addressed. Using an additional control pulse, the researchers also specifically triggered the emission of a photon that is entangled with the quantum state of the atom.

They  repeated this process several times and in a previously determined manner.

In between, the atom was manipulated in a certain way—in technical jargon: rotated. In this way, it was possible to create a chain of up to 14 light particles that were entangled with each other by the atomic rotations and brought into a desired state.

Because the chain of photons emerged from a single atom, it could be produced in a deterministic way. This means: in principle, each control pulse actually delivers a photon with the desired properties.

 Philip Thomas et al, Efficient generation of entangled multiphoton graph states from a single atom, Nature (2022). DOI: 10.1038/s41586-022-04987-5

Eye movements in REM sleep mimic gazes in the dream world

When our eyes move during REM sleep, we’re gazing at things in the dream world our brains have created, according to a new study by researchers.

REM sleep — named for the rapid eye movements associated with it — has been known since the 1950s to be the phase of sleep when dreams occur. But the purpose of the eye movements has remained a matter of much mystery and debate. 

This new work showed that these eye movements aren’t random. They’re coordinated with what's happening in the virtual dream world of the mouse.This work gives us a glimpse into the ongoing cognitive processes in the sleeping brain and at the same time solves a puzzle that’s triggered the curiosity of scientists for decades.

some experts hypothesized that these REM movements may be following scenes in the dream world, but there was little way to test it, and the experiments that could be done (noting a dreamers’ eye direction and then waking them up to ask where they were looking in the dream) provided contradictory results. Many researchers wrote off REM movements as random actions, perhaps to keep the eyelids lubricated.

Given much more advanced technology, researchers now were able to look at “head direction” cells in the brains of mice, who also experience REM sleep. These cells act something like a compass, and their activity shows researchers which direction the mouse perceives itself as heading. 

The team simultaneously recorded data from these cells about the mouse’s heading directions while monitoring its eye movements. Comparing them, they found that the direction of eye movements and of the mouse’s internal compass were precisely aligned during REM sleep, just as they do when the mouse is awake and moving around.  

The research team found that the same parts of the brain — and there are many of them — coordinate during both dreaming and wakefulness, lending credence to the idea that dreams are a way of integrating information gathered throughout the day. 

How those brain regions work together to produce this generative ability is the mystery .

https://www.science.org/doi/10.1126/science.abp8852

A battery powered by moisture from the air

Autoimmune disorders increase risk of cardiovascular disease

About 5% of the population in the world suffer from multiple autoimmune disorders. Examples are rheumatoid arthritis, psoriasis, systemic sclerosis, lupus erythematosus and type I diabetes. Although earlier research has suggested associations between some of these disorders and a higher risk of cardiovascular disease, these studies were often too small and limited to selected autoimmune or selected cardiovascular conditions to draw conclusive evidence on the necessity of cardiovascular disease prevention among patients with autoimmune disease, until now.

An international research team now presented the outcome of a thorough epidemiological investigation into possible links between 19 of the most common autoimmune disorders and cardiovascular disease. The results of the study show that patients with autoimmune disease have a substantially higher risk (between 1.4 and 3.6 times depending on which autoimmune condition) of developing cardiovascular disease than people without an autoimmune disorder. This excess risk is comparable to that of type 2 diabetes, a well-known risk factor for cardiovascular disease. The research shows for the first time that cardiovascular risks affect autoimmune disease as a group of disorders, rather than selected disorders individually.

In the research paper, which will be published in The Lancet, the authors show that the group of 19 autoimmune disorders they have studied accounts for about 6% of cardiovascular events. Importantly, excess cardiovascular risk was visible across the whole cardiovascular disease spectrum, beyond classical coronary heart disease, including infection-related heart disorders, heart inflammation, as well as thromboembolic and degenerative heart disorders, suggesting the implications of autoimmunity on cardiovascular health are likely to be much broader than originally thought.

Furthermore, the excess risk was not explained by traditional cardiovascular risk factors such as age, sex, socioeconomic status, blood pressure, BMI, smoking, cholesterol and type 2 diabetes. Another noteworthy finding: the excess risk is particularly high among patients with autoimmune disorders under 55 years and suggests that autoimmune disease is particularly important in causing premature cardiovascular disease, with the potential to result in a disproportionate loss of life years and disability.

 Autoimmune diseases and cardiovascular risk: a populationbased study on 19 autoimmune diseases and 12 cardiovascular diseases in 22 million individuals in the UK, The Lancet (2022). DOI: 10.1016/S0140-6736(22)01349-6

How light and temperature work together to affect plant growth

Plants lengthen and bend to secure access to sunlight. Despite observing this phenomenon for centuries, scientists do not fully understand it. Now, Salk scientists have discovered that two plant factors—the protein PIF7 and the growth hormone auxin—are the triggers that accelerate growth when plants are shaded by canopy and exposed to warm temperatures at the same time.

The findings, published in Nature Communications on August 29, 2022, will help scientists predict how plants will respond to climate change—and increase crop productivity despite the yield-harming global temperature rise.

Right now, we grow crops in certain densities, but our findings indicate that we will need to lower these densities to optimize growth as our climate changes. Understanding the molecualr basis of how plants respond to light and temperature will allow us to fine-tune crop density in a specific way that leads to the best yields.

Part 1

During sprouting, seedlings rapidly elongate their stems to break through the covering soil to capture sunlight as fast as possible. Normally, the stem slows down its growth after exposure to sunlight. But the stem can lengthen rapidly again if the plant is competing with surrounding plants for sunlight, or in response to warm temperatures to increase distance between the hot ground and the plant's leaves. While both environmental conditions—canopy shade and warm temperatures—induce stem growth, they also reduce yield.

In this study, the scientists compared plants growing in canopy shade and warm temperatures at the same time—a condition that mimics high crop density and climate change. The scientists used the model plant Arabidopsis thaliana, as well as tomato and a close relative of tobacco, because they were interested to see if all three plant species were affected similarly by this environmental condition.

Across all three species, the team found that the plants grew extremely tall when simultaneously trying to avoid the shade created by neighboring plants and being exposed to warmer temperatures. On a molecular level, the researchers discovered that transcription factor PIF7, a protein that helps turn genes "on" and "off," was the dominant player driving the increased rapid growth. They also found that the growth hormone auxin increased when the crops detected neighboring plants, which fostered growth in response to simultaneous warmer temperatures. This synergistic PIF7-auxin pathway allowed the plants to respond to their environments and adapt to seek the best growing conditions.

A related transcription factor, PIF4, also stimulated stem elongation during warm temperatures. However, when shade and increased temperatures were combined, this factor no longer played an important role.

The researchers think that there is another player, yet to be discovered, that is boosting the effect of PIF7 and auxin. They hope to explore this unknown factor in future studies.

Global temperatures are increasing, so we need food crops that can thrive in these new conditions.

Scientists now  identified key factors that regulate plant growth during warm temperatures, which will help us to develop better-performing crops to feed future generations.

 PIF7 is a master regulator of thermomorphogenesis in shade, Nature Communications (2022). DOI: 10.1038/s41467-022-32585-6

Part 2

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OPEN Access: The US has ruled all taxpayer-funded research must be free to read.

Last week, the United States announced an updated policy guidance on open access that will substantially expand public access to science not just in America, but worldwide.

As per the guidance, all US federal agencies must put in place policies and plans so anyone anywhere can immediately and freely access the peer-reviewed publications and data arising from research they fund.

The policies need to be in place by the end of 2025, according to President Biden’s White House Office of Science and Technology Policy (OSTP).

https://www.whitehouse.gov/ostp/news-updates/2022/08/25/breakthroug...

Mars' Moon Phobos Eclipses the Sun, as Seen by Curiosity

This video clip shows the larger of the two moons of Mars, Phobos, passing directly in front of the sun, in an eclipse photographed by NASA's Mars rover Curiosity.

Khufu branch of Nile River once flowed close enough to Giza to carry the stones needed to build the pyramids

A team of researchers  has found evidence that shows the Khufu branch of the Nile River once ran so close to Giza that it could have been used to carry the stones that were used to build the famous pyramids. In their paper published in Proceedings of the National Academy of Sciences, the group describes their study of fossilized pollen grains found in the sediments around Giza and what it showed them about the history of the Khufu branch.

In their work, the researchers obtained core sediment samples that have been collected from several sites in and around Giza over the years and then took a close look at the fossilized pollen grains trapped in them for thousands of years.

By combining results from prior studies that involved studying the rock layers surrounding the pyramids, they found that they were able to reconstruct the history of the Khufu branch as it flowed and ebbed in the area over the prior 8,000 years. Then, looking at the timeline and flow of the branch, they found its levels were high enough that it reached nearly all the way to Giza—7 kilometers from the Nile—during the times when three of the major pyramids (Menkaure, Khafre and Khufu) were built—approximately 4,000 years ago.

The researchers note that the pollen grain fossils they found were mostly from flowering grasses like the ones that line the Nile River today. They also found evidence of a few marsh plants, which typically grow on the edges of lakes—and that showed that the Khufu branch remained at high levels in the area long enough for nature to consider it permanent.

The researchers also found that not long after the reign of King Tutankhamun, levels of the branch began to drop, leading to a much more arid environment. Other studies of bones and teeth from mummies of the time also showed the area becoming much drier. The researchers suggest that others using the same techniques could learn more about how changing river flow impacted other ancient civilizations.

 Hader Sheisha et al, Nile waterscapes facilitated the construction of the Giza pyramids during the 3rd millennium BCE, Proceedings of the National Academy of Sciences (2022). DOI: 10.1073/pnas.2202530119

Breakthrough results in developing an oral insulin tablet

A team of researchers working on developing oral insulin tablets as a replacement for daily insulin injections have made a game-changing discovery.

Researchers have discovered that insulin from the latest version of their oral tablets is absorbed by rats in the same way that injected insulin is.

These exciting results show that scientists are on the right track in developing an insulin formulation that will no longer need to be injected before every meal, improving the quality of life, as well as mental health, of more than nine million type 1 diabetics around the world.

Researchers  are now seeing nearly 100 percent of the insulin from their tablets go straight into the liver. In previous attempts to develop a drinkable insulin, most of the insulin would accumulate in the stomach.

Even after two hours of delivery, researchers did not find any insulin in the stomachs of the rats they tested now. It was all in the liver and this is the ideal target for insulin—it's really what they wanted to see.

The team developed a different kind of tablet that isn't made for swallowing, but instead dissolves when placed between the gum and cheek.

This method makes use of the thin membrane found within the lining of the inner cheek and back of the lips (also known as the buccal mucosa). It delivered all the insulin to the liver without wasting or decomposing any insulin along the way.

Similar to the rapid-acting insulin injection, this new oral delivery tablet absorbs after half an hour and can last for about two to four hours long.

Now human trials are awaited. 

Yigong Guo et al, Production of high loading insulin nanoparticles suitable for oral delivery by spray drying and freeze drying techniques, Scientific Reports (2022). DOI: 10.1038/s41598-022-13092-6

Living in timber cities could avoid emissions, without using farmla...

Housing a growing population in homes made out of wood instead of conventional steel and concrete could avoid more than 100 billion tons of emissions of the greenhouse gas CO2 until 2100, a new study by the Potsdam Institute for Climate Impact Research shows. These are about 10% of the remaining carbon budget for the 2°C climate target. Besides the harvest from natural forests, newly established timber plantations are required for supplying construction wood. While this does not interfere with food production, a loss of biodiversity may occur if not carefully managed, according to the scientists. The study is the first to analyze the impacts of a large-scale transition to timber cities on land use, land-use change emissions, and long-term carbon storage in harvested wood products.

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Researchers reveal how salt may play into climate warming

A team of Skoltech researchers has published a series of three papers dealing with various aspects of how salt from the ocean water and other salts penetrate into frozen soil that contains gas hydrates—icelike crystals composed of water and gas, mostly methane. This so-called salt migration affects the rate at which permafrost melts as global warming advances. Taking that process into account is therefore necessary for accurate climate change modeling. The research findings are reported in papers dated June 27 and July 9 in the journal Geosciences, and in the July 5 paper in Energy & Fuels.

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Shape of coronavirus affects its transmission, study finds

Since the start of the COVID-19 pandemic, images of the coronavirus, SARS-CoV-2, have been seared in our minds. But the way we picture the virus, typically as a sphere with spikes, is not strictly accurate. Microscope images of infected tissues have revealed that coronavirus particles are actually ellipsoidal, displaying a wide variety of squashed and elongated shapes.

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Compound found in trees has potential to kill drug-resistant bacteria

University of Portsmouth researchers have found a naturally occurring compound, known as hydroquinine, has bacterial killing activity against several microorganisms.

New research in mice offers clues into how the brain processes sensory information from internal organs

Most of us think little of why we feel pleasantly full after eating a big holiday meal, why we start to cough after accidentally inhaling campfire smoke, or why we are hit with sudden nausea after ingesting something toxic. However, such sensations are crucial for survival: they tell us what our bodies need at any given moment so that we can quickly adjust our behavior.

Yet historically, very little research has been devoted to understanding these basic bodily sensations—also known as internal senses—that are generated when the brain receives and interprets input from internal organs.

Now, a team led by researchers at Harvard Medical School has made new strides in understanding the basic biology of internal organ sensing, which involves a complicated cascade of communication between cells inside the body.

In a study conducted in mice and published Aug. 31 in Nature, the team used high-resolution imaging to reveal spatial maps of how neurons in the brain stem respond to feedback from internal organs.

They found that feedback from different organs activates discrete clusters of neurons, regardless of whether this information is mechanical or chemical in nature—and these groups of neurons representing different organs are topographically organized in the brain stem. Moreover, they discovered that inhibition within the brain plays a key role in helping neurons selectively respond to organs.

The research is only a first step in elucidating how internal organs communicate with the brain. However, if the findings are confirmed in other species, including humans, they could help scientists develop better therapeutic strategies for diseases such as eating disorders, overactive bladder, diabetes, pulmonary disorders, and hypertension that arise when internal sensing goes awry.

Stephen Liberles, A brainstem map for visceral sensations, Nature (2022). DOI: 10.1038/s41586-022-05139-5. www.nature.com/articles/s41586-022-05139-5

Researchers find spaceflight may be associated with DNA mutations, increased risk of heart disease and cancer

Astronauts are at higher risk for developing mutations—possibly linked to spaceflight—that can increase the risk of developing cancer and heart disease during their lifetimes, according to a first-of-its kind study from the Icahn School of Medicine at Mount Sinai.

A team of researchers collected blood samples from National Aeronautics and Space Administration (NASA) astronauts who flew space shuttle missions between 1998 and 2001. They discovered DNA mutations, known as soamtic mutations, in the blood-forming system ( hematopoietic stem cells)  in all 14 astronauts studied.

Their findings, published in the August issue of Communications Biology, suggest that spaceflight could be associated with these mutations and emphasize the importance of ongoing blood screening of astronauts throughout their careers and during their retirement to monitor their health.

Somatic mutations are mutations that occur after a person is conceived and in cells other than sperm or egg cells, meaning they cannot be passed on to offspring. The mutations identified in this study were characterized by the overrepresentation of blood cells derived from a single clone, a process called clonal hematopoiesis (CH).

Such mutations are frequently caused by environmental factors, such as exposure to ultraviolet radiation or certain chemicals, and may be a result of cancer chemo- or radiotherapy. There are few signs or symptoms associated with CH; most patients are identified after genetic testing of their blood for other diseases. Although CH is not necessarily an indicator of disease, it is associated with a higher risk for cardiovascular disease and blood cancer.

Astronauts work in an extreme environment where many factors can result in somatic mutations, most importantly space radiation, which means there is a risk that these mutations could develop into clonal hematopoiesis. Given the growing interest in both commercial spaceflights and deep space exploration, and the potential health risks of exposure to various harmful factors that are associated with repeated or long-duration exploration space missions.

 Agnieszka Brojakowska et al, Retrospective analysis of somatic mutations and clonal hematopoiesis in astronauts, Communications Biology (2022). DOI: 10.1038/s42003-022-03777-z

Excessive blue light from our gadgets may accelerate the aging process

Too much screen use has been linked to obesity and psychological problems. Now a new study has identified a new problem—a study in fruit flies suggests our basic cellular functions could be impacted by the blue light emitted by these devices. These results are published in Frontiers in Aging.

Excessive exposure to blue light from everyday devices, such as TVs, laptops, and phones, may have detrimental effects on a wide range of cells in our body, from skin and fat cells, to sensory neurons. 

This work is the first to show that the levels of specific metabolites—chemicals that are essential for cells to function correctly—are altered in fruit flies exposed to blue light. This study suggests that avoidance of excessive blue light exposure may be a good anti-aging strategy. 

Highlights of this work:

Blue light exposure caused significant differences in the levels of metabolites measured by the researchers in the cells of fly heads. In particular, they found that the levels of the metabolite succinate were increased, but glutamate levels were lowered.

Succinate is essential for producing the fuel for the function and growth of each cell. High levels of succinate after exposure to blue light can be compared to gas being in the pump but not getting into the car.

Another troubling discovery was that molecules responsible for communication between neurons, such as glutamate, are at the lower level after blue light exposure.

The changes recorded by the researchers suggest that the cells are operating at suboptimal level, and this may cause their premature death, and further, explain their previous findings that blue light accelerates aging.

"LEDs have become the main illumination in display screens such as phones, desktops and TVs, as well as ambient lighting, so humans in advanced societies are exposed to blue light through LED lighting during most of their waking hours. The signaling chemicals in the cells of flies and humans are the same, so the there is potential for negative effects of blue light on humans too, according to researchers.

Jun Yang et al, Chronic blue light leads to accelerated aging in Drosophila by impairing energy metabolism and neurotransmitter levels, Frontiers in Aging (2022). DOI: 10.3389/fragi.2022.983373

Scientists eavesdrop on communication between fat and brain

For years, it was assumed that hormones passively floating through the blood were the way that a person's fat—called adipose tissue—could send information related to stress and metabolism to the brain. Now,  Research scientists report in Nature that newly identified sensory neurons carry a stream of messages from adipose tissue to the brain.

The discovery of these neurons suggests for the first time that your brain is actively surveying your fat, rather than just passively receiving messages about it. The implications of this finding are profound.

This is yet another example of how important sensory neurons are to health and disease in the human body.

In mammals, adipose tissue stores energy in the form of fat cells and, when the body needs energy, releases those stores. It also controls a host of hormones and signaling molecules related to hunger and metabolism. In diseases including diabetes, fatty liver disease, atherosclerosis and obesity, that energy storage and signaling often goes awry. Researchers have long known that nerves extend into adipose tissue, but suspected they weren't sensory neurons that carry data to the brain. Instead, most hypothesized that the nerves in fat belonged mostly to the sympathetic nervous system—the network responsible for our fight-or-flight response, which switches on fat-burning pathways during times of stress and physical activity. Attempts to clarify the types and functions of these neurons have been difficult; methods used to study neurons closer to the surface of the body or in the brain don't work well deep in adipose tissue, where nerves are hard to see or to stimulate.

Part 1

The experiments revealed that when the brain doesn't receive sensory messages from adipose tissue, programs triggered by the sympathetic nervous system—related to the conversion of white fat to brown fat—become overly active in fat cells, resulting in a larger than normal fat pad with especially high levels of brown fat, which breaks down other fat and sugar molecules to produce heat. Indeed, the animals with blocked sensory neurons—and high levels of sympathetic signaling—had increased body temperatures.

The findings suggest that the sensory neurons and sympathetic neurons might have two opposing functions, with sympathetic neurons needed to turn on fat burning and the production of brown fat, and sensory neurons required to turn these programs down.

This tells us that there's not just a one-size-fits-all instruction that brain sends adipose tissue. It's more nuanced than that; these two types of neurons are acting like a gas pedal and a brake for burning fat.

Li Ye, The role of somatosensory innervation of adipose tissues, Nature (2022). DOI: 10.1038/s41586-022-05137-7. www.nature.com/articles/s41586-022-05137-7

Part 2

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How the brain generates rhythmic behaviour

Many of our bodily functions, such as walking, breathing, and chewing, are controlled by brain circuits called central oscillators, which generate rhythmic firing patterns that regulate these behaviours.

neuroscientists have now discovered the neuronal identity and mechanism underlying one of these circuits: an oscillator that controls the rhythmic back-and-forth sweeping of tactile whiskers, or whisking, in mice. This is the first time that any such oscillator has been fully characterized in mammals.

The research team found that the whisking oscillator consists of a population of inhibitory neurons in the brainstem that fires rhythmic bursts during whisking. As each neuron fires, it also inhibits some of the other neurons in the network, allowing the overall population to generate a synchronous rhythm that retracts the whiskers from their protracted positions.

 Shwetha Srinivasan et al, Ligand-induced transmembrane conformational coupling in monomeric EGFR, Nature Communications (2022). DOI: 10.1038/s41467-022-31299-z

Climate change: 

This Hot Summer Is One of the Coolest of the Rest of Our Lives

Heat waves broke temperature records around the world this past summer, but it will still be one of the coolest summers of the next few decades!

Physicists on Earth are experimenting with matter which is about 3 billion times colder than deep space!

Physicists have used atoms about 3 billion times colder than interstellar space to open a portal to an unexplored realm of quantum magnetism.

Unless an alien civilization is doing experiments like these right now, anytime this experiment is running at Kyoto University, Japan,  it is making the coldest fermions in the universe. Fermions are not rare particles. They include things like electrons and are one of two types of particles that all matter is made of.

Fermions are not rare particles. They include things like electrons and are one of two types of particles that all matter is made of.

Researchers used lasers to cool its fermions, atoms of ytterbium, within about one-billionth of a degree of absolute zero, the unattainable temperature where all motion stops. That's about 3 billion times colder than interstellar space, which is still warmed by the afterglow from the Big Bang.

The payoff of getting this cold is that the physics really changes. The physics starts to become more quantum mechanical, and it lets you see new phenomena.

 Shintaro Taie, Observation of antiferromagnetic correlations in an ultracold SU(N) Hubbard model, Nature Physics (2022). DOI: 10.1038/s41567-022-01725-6. www.nature.com/articles/s41567-022-01725-6

Mice grow bigger on the rainier sides of mountains: It might be a new rule of nature.

Scientists studying mice from the Andes Mountains in Patagonia noticed something they couldn't explain: the mice from the western side of the mountains were bigger than the ones from the east, but DNA said that they were all from the same species. The researchers examined the skulls of 450 mice from the southern tip of South America, and found that existing biological laws didn't explain the size differences. Instead, in a new paper in the Journal of Biogeography, the scientists put forth a new hypothesis: the mice on the western slopes were bigger because that side of the mountain range gets more rain, which means there's more plentiful food for the mice to eat.

There are a bunch of ecogeographic rules that scientists use to explain trends that we see again and again in nature. With this paper, researchers might have found a new one: the rain shadow effect can cause changes of size and shape in mammals.

Some individuals of the mice species were really big, and some were really small. Researchers thought they were different species. But their mitochondrial DNA suggested that they were one species, even though they're so different.

Part 1

There are lots of "rules" of nature explaining patterns that we see in life. For instance, Bergmann's rule explains why animals of the same species are bigger in higher latitudes. White-tailed deer in Canada are larger and bulkier than their skinny Floridian cousins. Bergmann's rule explains that this is because having a thicker body in relation to your surface area helps you retain heat better, the same way that big pieces of food take longer to cool down than smaller bites.

To try to find a pattern to explain the differences in size, the researchers used statistical analyses to compare measurements of 450 mouse skulls. They then tried to map their findings onto different biological rules to see if any fit. Bergmann's rule didn't work; there wasn't a strong correlation between mouse size and how far north or south the specimen lived. Other rules emphasize the role of temperature or precipitation, with mixed results for different groups and situations. This team did not find that latitude, or one of 19 other bioclimatic, temperature, or precipitation variables, best described the mice's varying shapes and sizes. However, there did seem to be a pattern with longitude— how far east or west the mice lived.

This might be related to what biologists call the "resource rule." This rule suggests that where there are more resources, individuals from the same species tend to be larger than where there are fewer resources. For instance, some deer mice that are found in deserts and other habitats tend to be smaller in drier portions of their habitats. Another hypothesis suggests that some animals tend to be smaller in mountains versus adjacent plains in North America. This new study found a mixed result of these rules.

 Noé de la Sancha et al, Andean rain shadow effect drives phenotypic variation in a widely distributed Austral rodent, Journal of Biogeography (2022).

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Carbon dioxide should cost 3.6 times more than US price, study says

Each ton of carbon dioxide that exits a smokestack or tailpipe is doing far more damage than what governments take into account, researchers conclude in a scientific paper published recently. 

Major hurricanes pack more rain, while extremes of wildfire, drought and downpours are all happening more often and with more intensity due to climate change, causing loss of communities, homes and lives all over the world. But what is the actual cost in dollar terms of the carbon emissions driving climactic change?

That's what researchers from a variety of fields—science, economics, medicine—are trying to figure out through a metric called the social cost of carbon, a price that represents the total climate damage caused to society through carbon emissions. It's been used in the past to justify tougher limits on carbon emissions and more spending on climate solutions, like transitioning to renewable energy and natural flood protection.

Currently, the United States government uses a price of $51 per ton of carbon dioxide emitted, but the researchers wrote in the journal Nature that the price should be $185 per ton—3.6 times higher than the current U.S. standard.

David Anthoff, Comprehensive Evidence Implies a Higher Social Cost of CO₂, Nature (2022). DOI: 10.1038/s41586-022-05224-9. www.nature.com/articles/s41586-022-05224-9

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Europe's fiery summer: a climate 'reality check'? Wildfires and storms. Rivers at record lows. Parched crops withering in the fields. For many Europeans, this year's scorching summer means climate change is increasingly hard to ignore.

Circadian rhythm disruption found to be common among mental health disorders

Anxiety, autism, schizophrenia and Tourette syndrome each have their own distinguishing characteristics, but one factor bridging these and most other mental disorders is circadian rhythm disruption, according to a team of neuroscience, pharmaceutical sciences and computer science researchers .

In an article published recently in the Nature journal Translational Psychiatry, the scientists hypothesize that CRD is a psychopathology factor shared by a broad range of mental illnesses and that research into its molecular foundation could be key to unlocking better therapies and treatments.

Circadian rhythms regulate our bodies' physiological activity and biological processes during each solar day. Synchronized to a 24-hour light/dark cycle, circadian rhythms influence when we normally need to sleep and when we're awake. They also manage other functions such as hormone production and release, body temperature maintenance and consolidation of memories. Effective, nondisrupted operation of this natural timekeeping system is necessary for the survival of all living organisms.

Circadian rhythms are intrinsically sensitive to light/dark cues, so they can be easily disrupted by light exposure at night, and the level of disruption appears to be sex-dependent and changes with age. One example is a hormonal response to CRD felt by pregnant women; both the mother and the fetus can experience clinical effects from CRD and chronic stress.

Circadian rhythms play a fundamental role in all biological systems at all scales, from molecules to populations. This new work analysis found that circadian rhythm disruption is a factor that broadly overlaps the entire spectrum of mental health disorders.

The telltale sign of circadian rhythm disruption—a problem with sleep—was present in each disorder.While  the focus was on widely known conditions including autism, ADHD and bipolar disorder, researchers argue that the CRD psychopathology factor hypothesis can be generalized to other mental health issues, such as obsessive-compulsive disorder, anorexia nervosa, bulimia nervosa, food addiction and Parkinson's disease. The researchers found ample evidence of the connection by thoroughly examining peer-reviewed literature on the most prevalent mental health disorders.

Amal Alachkar et al, The hidden link between circadian entropy and mental health disorders, Translational Psychiatry (2022). DOI: 10.1038/s41398-022-02028-3

Researcher unlocks mystery of 'chemo-brain,' identifies possible treatment

Though chemotherapy can be lifesaving, the cancer treatment often leaves patients suffering from debilitating side effects, including cognitive impairments in processing speed, memory, executive function and attention. Dubbed "chemo brain," these lingering symptoms can dramatically impact patients' quality of life long after they have completed their cancer treatments.

This is the first evidence that chemotherapy alters an important cellular pathway called sphingolipid metabolism in critical areas of the brain linked to cognitive function.

Currently, there are no FDA-approved drugs to mitigate these deficits. In breakthrough findings, researchers have uncovered some of the molecular events that happen when chemotherapy drugs cause these deficits. More promising still, they've found that an already-approved FDA drug designed to treat multiple sclerosis also appears to work to reduce chemotherapy-related cognitive impairment (CRCI).

 Silvia Squillace et al, Sphingosine-1-phosphate receptor 1 activation in the central nervous system drives cisplatin-induced cognitive impairment, Journal of Clinical Investigation (2022). DOI: 10.1172/JCI157738

Study finds enzyme in the brain is a 'metastat' for body weight

An enzyme found in the brain acts as a major regulator of body weight,  researchers have discovered. In a new study, they found that removing the enzyme from neurons in a part of the brain known as the hypothalamus led mice to gain weight and burn less fat. This finding, they say, suggests that the enzyme could be a target for treating metabolic disease.

The findings were published Aug. 31 in Science Advances.

Dysregulated metabolism is implicated in a host of metabolic disorders, including obesity and diabetes. The hypothalamus region of the brain is essential for metabolic control and the area known as the ventromedial hypothalamus is known to regulate body weight, eating, and glucose balance. How the ventromedial hypothalamus does this, however, is less clear.

For the study,  researchers focused on an enzyme called O-linked b-D-N-acetylglucosamine transferase, or OGT. Though researchers have a partial understanding of the enzyme’s role in other parts of the body — such as mediating nutritional and hormonal regulation in different organs and tissues — what it does in the brain is largely unknown.

As a first step, researchers observed what happened to OGT in neurons of the ventromedial hypothalamus when food intake was adjusted. They found that when mice consumed less food, OGT levels went up.

This suggested that OGT plays an important role as a nutrient sensor in this neuron population.

To better understand this role, researchers bred mice that lacked OGT in neurons of the ventromedial hypothalamus. They found that the mice gained weight very quickly on a normal diet, becoming much heavier than typical mice even though they were eating the same amount of food and were just as physically active.

A key difference was that the mice without OGT expended less energy than their counterparts.

Just sitting at rest, you burn energy because you need to maintain the vital functions of the body, such as breathing, digestion, and brain activity. And though the mice lacking OGT weren’t less physically active, they burned less energy at this basal level.

They also responded differently to fasting. When the body has adequate amounts of food, its preferred fuel is glucose. But when you fast, your glucose runs out quickly. The body then taps into its fat stores in order to meet energy demands.

But in the study, mice lacking OGT didn’t burn fat as much as other mice when food was restricted.

The problem had to do with glucose-sensing, said the researchers. The ability to sense glucose is essential for keeping it at the level the body needs. If neurons can’t sense glucose properly, they won’t make necessary metabolic adjustments, such as telling the body to burn fat. In the study, neurons without OGT didn’t sense glucose as well as those with the enzyme.

Without OGT, the body can’t sense that less food is coming in, and then it doesn’t tell its fat tissues to burn fat. Researchers liken OGT to a thermostat, or a “metastat,”  since OGT is crucial for metabolic homeostasis.


And that set point will be different from individual to individual.

Because of this, OGT could be a target for treating metabolic diseases. It’s possible that, in the future, a drug could be used to target OGT in ventromedial hypothalamus neurons to fine-tune a person’s body weight set point, adjusting it if it’s too high or too low.

One day we might be able to reprogram a person’s metastat to achieve desired body weight, the researchers think.

https://news.yale.edu/2022/08/31/study-finds-enzyme-brain-metastat-...

Your blood type could predict your risk of having a stroke before age 60, new study suggests

A person's blood type may be linked to their risk of having an early stroke, according to a new meta-analysis done by researchers. Findings were published today in the journal Neurology. The meta-analysis included all available data from genetic studies focusing on ischemic strokes, which are caused by a blockage of blood flow to the brain, occurring in younger adults under age 60.

The number of people with early strokes is rising. These people are more likely to die from the life-threatening event, and survivors potentially face decades with disability. Despite this, there is little research on the causes of early strokes.

Researchers conducted the study by performing a meta-analysis of 48 studies on genetics and ischemic stroke that included 17,000 stroke patients and nearly 600,000 healthy controls who never had experienced a stroke. They then looked across all collected chromosomes to identify genetic variants associated with a stroke and found a link between early-onset stroke—occurring before age 60—and the area of the chromosome that includes the gene that determines whether a blood type is A, AB, B, or O.

The study found that people with early stroke were more likely to have blood type A and less likely to have blood type O (the most common blood type)—compared to people with late stroke and people who never had a stroke. Both early and late stroke were also more likely to have blood type B compared to controls. After adjusting for sex and other factors, researchers found those who had blood type A had an 16 percent higher risk of having an early stroke than people with other blood types. Those who had blood type O had a 12 percent lower risk of having a stroke than people with other blood types.

The researchers emphasized that the increased risk was very modest and that those with type A blood should not worry about having an early-onset stroke or engage in extra screening or medical testing based on this finding.

Genetic Contributions to Early and Late Onset Ischemic Stroke, Neurology (2022). dx.doi.org/10.1212/WNL.0000000000201006

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The physics of walking: For multi-legged creatures, it's a lot like slithering

New polar ring galaxy discovered

Astronomers report the detection of a new polar ring galaxy using the data obtained with the Subaru Telescope as part of the Hyper Suprime-Cam Subaru Strategic Program (HSC-SSP). 

The so-called polar ring galaxies (PRGs) are systems composed of an S0-like galaxy and a polar ring, which remain separate for billions of years. In general, these outer polar rings, composed of gas and stars, are aligned roughly in a perpendicular orientation with respect to the major axis of the central host galaxy.

However, although more than 400 PRG candidates have been discovered to date, only dozens of them have been confirmed as real polar ring galaxies by follow-up spectroscopic observations.

Minoru Nishimura, Kazuya Matsubayashi, Takashi Murayama, Yoshiaki Taniguchi, A New Polar Ring Galaxy Discovered in the COSMOS Field. arXiv:2208.12388v1 [astro-ph.GA], arxiv.org/abs/2208.12388

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Training astronauts to be scientists on the moon

Astronauts with their sights on the moon are receiving world-class geology training during the fifth edition of ESA's Pangaea campaign. From choosing landing sites for a future Artemis mission, to designing science operations for the lunar surface, the course challenges space explorers to become field scientists.

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It's raining diamonds across the universe, research suggests It could be raining diamonds on planets throughout the universe, scientists suggested Friday, after using common plastic to recreate the strange precipitation believed to form deep inside Uranus and Neptune. -- Soil temperature can predict pest spread in crops A new study from North Carolina State University shows soil temperature can be used to effectively monitor and predict the spread of the corn earworm (Helicoverpa zea), a pest that ravages corn, cotton, soybeans, peppers, tomatoes and other vegetable crops. The ability to better monitor the pest and make predictions about where it will appear could help farmers control the pest more effectively, which would reduce the financial and environmental impacts of pesticide use. -- Bees use patterns, not just colors, to find flowers Honeybees rely heavily on flower patterns—not just colors—when searching for food, new research shows.

Breakthrough in addressing glioblastoma, a deadly brain cancer

Researchers capture live footage of virus infecting cell

In a first, scientists have captured on video all the steps a virus follows as it enters and infects a living cell in real time and in three dimensions.

Scientists achieved the feat by using advanced imaging called lattice light sheet microscopy as well as chemical and genetic manipulation.

The first part of the video shown here follows a virus engineered to sprout SARS-CoV-2 spike proteins (labeled pink) as it is captured at a cell surface and engulfed by a cellular compartment called an endosome. The virus then fuses with the endosome membrane and injects its genetic material (labeled blue) inside the cell—the steps necessary to kick off a cycle of viral infection and replication.

The second part of the video shows many such viruses inside the cell. The video covers 4 minutes of activity, with snapshots taken every 4 seconds.

The findings, published Sept. 1 in PNAS, provide new insights into the fundamental mechanics of viral infection and could point the way to new methods for intervening before the onset of COVID-19.

The researchers' work reveals that viruses can't fuse with the membrane and release their genomes unless they're bathed in a slightly acidic environment. Experiments indicated that the pH must fall between 6.2 and 6.8, just shy of neutral and on par with bodily fluids such as saliva and urine. Endosomes have such acidity, and the team's measurements confirmed that this is also the pH range inside a typical human nose, where SARS-CoV-2 infection often begins.

https://hms.harvard.edu/news/breaking-entering

Webb Captures A Cosmic Tarantula

Watch this special Space Sparks episode to learn more about the stellar nursery called 30 Doradus, as captured by the NASA/ESA/CSA James Webb Space Telescope.

Researchers discover toxin that kills bacteria in unprecedented ways

Researchers  have discovered a previously unknown bacteria-killing toxin that could pave the way for a new generation of antibiotics.

The study shows that the bacterial pathogen Pseudomonas aeruginosa, known to cause hospital-acquired infections such as pneumonia, secretes a toxin that has evolved to kill other  species of bacteria.

The key aspect of his discovery is not just that this toxin kills bacteria, but how it does so.This research is significant, because it shows that the toxin targets essential RNA molecules of other bacteria, effectively rendering them non-functional. It's a total assault on the cell because of how many essential pathways depend on functional RNAs. This toxin enters its target, hijacks an essential molecule needed for life, and then uses that molecule to disrupt normal processes.

Researchers say that this development holds great potential for future research that could eventually lead to new innovations that combat infection-causing bacteria.

They think the newly-discovered vulnerability can be exploited for future antibiotic development.

An ADP-ribosyltransferase toxin kills bacterial cells by modifying structured non-coding RNAs, Molecular Cell (2022).