Experts discover how zebra stripes work to thwart horsefly attacks

According to this new discovery, stark black-white distinctions and small dark patches are particularly effective in thwarting horsefly attack. These characteristics specifically eliminate the outline of large monochrome dark patches that are attractive to horseflies at close distances.

 A team of researchers theorized that the thin back stripes serve to minimize the size of local features on a zebra that are appealing to the biting flies.

We knew that horseflies are averse to landing on striped objects—a number of studies have now shown this, but it is not clear which aspects of stripes they find aversive. Is it the thinness of the stripes? The contrast of black and white? The polarized signal that can be given off objects? So researchers  set out to explore these issues using different patterned cloths draped over horses and filmed incoming horseflies. 

The team found that tabanid horseflies are attracted to large dark objects in their environment but less to dark broken patterns. All-gray coats were associated with by far the most landings, followed by coats with large black triangles placed in different positions, then small checkerboard patterns in no particular order. In another experiment, they found contrasting stripes attracted few flies whereas more homogeneous stripes were more attractive.

This suggests that any hoofed animal that reduces its overall dark outline against the sky will benefit in terms of reduced ectoparasite attack.

Tim Caro et al, Why don't horseflies land on zebras?, Journal of Experimental Biology (2023). DOI: 10.1242/jeb.244778

Scientists make stunning discovery, find new protein activity in telomeres

Once thought incapable of encoding proteins due to their simple monotonous repetitions of DNA, tiny telomeres at the tips of our chromosomes seem to hold a potent biological function that's potentially relevant to our understanding of cancer and aging.

Reporting in the Proceedings of the National Academy of Sciences

researchers made the stunning discovery that telomeres contain genetic information to produce two small proteins, one of which they found is elevated in some human cancer cells, as well as cells from patients suffering from telomere-related defects.

Based on this research, they think simple blood tests for these proteins could provide a valuable screen for certain cancers and other human diseases. These tests also could provide a measure of 'telomere health,' because we know telomeres shorten with age.

Telomeres contain a unique DNA sequence consisting of endless repeats of TTAGGG bases that somehow inhibit chromosomes from sticking to each other. Two decades ago, researchers showed that the end of a telomere's DNA loops back on itself to form a tiny circle, thus hiding the end and blocking chromosome-to-chromosome fusions. When cells divide, telomeres shorten, eventually becoming so short that the cell can no longer divide properly, leading to cell death.

Scientist first identified telomeres about 80 years ago, and because of their monotonous sequence, the established dogma in the field held that telomeres could not encode for any proteins, let alone ones with potent biological function.

Researchers now conducted experiments—as described in the PNAS paper—to show how telomeric DNA can instruct the cell to produce signaling proteins they termed VR (valine-arginine) and GL (glycine-leucine). Signaling proteins are essentially chemicals that trigger a chain reaction of other proteins inside cells that then lead to a biological function important for health or disease.

They then chemically synthesized VR and GL to examine their properties using powerful electron and confocal microscopes along with state-of-the-art biological methods, revealing that the VR protein is present in elevated amounts in some human cancer cells, as well as cells from patients suffering from diseases resulting from defective telomeres.

It is it's possible that as we age, the amount of VR and GL in our blood will steadily rise, potentially providing a new biomarker for biological age as contrasted to chronological age. Scientists think inflammation may also trigger the production of these proteins.

 Al-Turki, Taghreed M. et al, Mammalian telomeric RNA (TERRA) can be translated to produce valine–arginine and glycine–leucine dipeptide repeat proteins, Proceedings of the National Academy of Sciences (2023). DOI: 10.1073/pnas.2221529120

Indian women face fieldwork challenges

Female researchers face challenges participating in fieldwork in India — from trained local residents refusing to work with women to objections from family members over travel, prejudices surrounding the type of work considered appropriate for women, and a lack of role models. Although the extent of the effect is hard to measure, women in the country are under-represented in fields that require extensive fieldwork such as geology, evolutionary biology and environmental studies. “Changing that image of what a scientist and a field researcher should look like, should be the first step. Let’s start there,” says evolutionary biologist Ashwini Mohan.

https://www.rukhmabai.com/despite-progress-fieldwork-remains-a-stum...

Physicists create new model of ringing black holes

When two black holes collide into each other to form a new bigger black hole, they violently roil spacetime around them, sending ripples, called gravitational waves, outward in all directions. Previous studies of black hole collisions modeled the behavior of the gravitational waves using what is known as linear math, which means that the gravitational waves rippling outward did not influence, or interact, with each other. Now, a new analysis has modeled the same collisions in more detail and revealed so-called nonlinear effects.

Nonlinear effects are what happens when waves on the beach crest and crash. The waves interact and influence each other rather than ride along by themselves. With something as violent as a black hole merger, researchers expected these effects but had not seen them in their models until now. New methods for extracting the waveforms from their simulations have made it possible to see the nonlinearities.

In the future, the new model can be used to learn more about the actual black hole collisions that have been routinely observed by LIGO (Laser Interferometer Gravitational-wave Observatory) ever since it made history in 2015 with the first direct detection of gravitational waves from space. LIGO will turn back on later this year after getting a set of upgrades that will make the detectors even more sensitive to gravitational waves. Supercomputers are needed to carry out an accurate calculation of the entire signal: the inspiral of the two orbiting black holes, their merger, and the settling down to a single quiescent remnant black hole.

Keefe Mitman et al, Nonlinearities in black hole ringdowns, Physical Review Letters (2023). Accepted for publication: journals.aps.org/prl/accepted/ … 5c5aaa672c0e199adcff. On Arxiv: DOI: 10.48550/arxiv.2208.07380

Cellular senescence plays a significant role in cerebral tumours

Glioblastomas are the most common malignant tumors of the adult brain. They resist conventional treatment, including surgery, followed by radiation therapy and chemotherapy. Despite this armamentarium, glioblastomas inexorably recur.

In a new study published in Nature Communications, researchers have shown that the elimination of senescent cells, i.e., cells that have stopped dividing, can modify the tumor ecosystem and slow its progression. These results open up new avenues for treatment.

Glioblastoma, the most common adult brain cancer, affects 2 to 5 in 100,000 individuals. While the incidence of the disease is highest in those between 55 and 85 years old, it is increasing in all age groups. This effect can't be attributed to improved diagnostic techniques alone, suggesting the influence of environmental factors hitherto unidentified.

People with the disease have a median survival of 15 months after diagnosis, as the tumor infiltrates the brain very quickly. There is an urgent need to better understand the biology of the tumor, including the diversity of cell types of which it is composed, and their role. The challenge is to find new therapeutic targets and significantly increase the lifespan of patients.

Finding the weak spot of glioblastoma is no easy task. One recent approach consists in targeting a key biological process: cellular senescence. Initially identified during the normal aging of cells, it corresponds to the loss of their ability to divide. Interruption of the cell cycle has an advantage: it prevents the uncontrolled division of malignant cells. In that case, senescence contributes to the body's anti-tumor response.

Long considered a simple marker of aging, we now know that senescence occurs throughout life, especially in response to genotoxic stress—that is, an event that disrupts or damages DNA, such as chemotherapy

When cells enter senescence, they secrete various molecules. This is called the senescence-associated secretory phenotype—or secretome. The secretome can influence the cellular environment in a beneficial or detrimental way. For example, it can activate the immune system or, conversely, induce the formation of blood vessels that contribute to the irrigation of the cancerous tissue. It all depends on the molecules secreted.

Part 1

Although the effects of senescence may seem paradoxical at first sight, recent studies show that it is all a question of temporality... and context. "In the short term, the secretome is involved in recruiting immune cells to eliminate tumor cells. But in the long term, the accumulation of senescent cells can promote the destruction of the extracellular matrix—which allows the organization of cells into tissue—and the proliferation of malignant cells." The researchers wondered whether there was senescence in glioblastoma and, if so, what role it might play in the cancer progression. To do this, they investigated both an animal model of glioblastoma and tumor tissue removed from patients during surgery. The team first examined 28 patient tumors. They found, in varying proportions (0.4% to 7% of the original mass of glioblastoma), senescent cells of different cell types—tumoral, immune, or glial—located mainly in areas of malignant cell proliferation, as well as in necrosis zones. In mice, suppressing a part of the senescent tumor cells made it possible to modify the immune activity within the tumor and extend the animal's lifespan. The researchers then defined a characteristic signature of senescence based on the expression of 31 genes in mice and ensured that it was identical in humans. Researchers observed that the strong expression of this signature was associated with a poor prognosis. This shows the pro-tumor action of senescence in glioblastoma. Modulating cellular senescence could therefore constitute a new therapeutic avenue to be combined with conventional treatments—to increase their effectiveness.

Rana Salam et al, Cellular senescence in malignant cells promotes tumor progression in mouse and patient Glioblastoma, Nature Communications (2023). DOI: 10.1038/s41467-023-36124-9

Part 2

**

Discovery of massive early galaxies defies prior understanding of the universe

Six massive galaxies discovered in the early universe are upending what scientists previously understood about the origins of galaxies in the universe.

These objects are way more massive than anyone expected. Researchers expected only to find tiny, young, baby galaxies at this point in time, but they've discovered galaxies as mature as our own in what was previously understood to be the dawn of the universe.

Using the first dataset released from NASA's James Webb Space Telescope, the international team of scientists discovered objects as mature as the Milky Way when the universe was only 3% of its current age, about 500-700 million years after the Big Bang. The telescope is equipped with infrared-sensing instruments capable of detecting light that was emitted by the most ancient stars and galaxies. Essentially, the telescope allows scientists to see back in time roughly 13.5 billion years, near the beginning of the universe as we know it.

But scientists think this is their first glimpse back this far, so it's important that they keep an open mind about what they are seeing. While the data indicates they are likely galaxies, they think there is a real possibility that a few of these objects turn out to be obscured supermassive black holes. Regardless, the amount of mass they discovered means that the known mass in stars at this period of our universe is up to 100 times greater than they had previously thought. Even if they cut the sample in half, this is still an astounding change.

In a paper published recently (Feb. 22) in Nature, the researchers show evidence that the six galaxies are far more massive than anyone expected and call into question what scientists previously understood about galaxy formation at the very beginning of the universe.

The revelation that massive galaxy formation began extremely early in the history of the universe upends what many of us had thought was settled science. Scientists have been informally calling these objects 'universe breakers'—and they have been living up to their name so far.

 Accounting for such a high amount of mass would require either altering the models for cosmology or revising the scientific understanding of galaxy formation in the early universe—that galaxies started as small clouds of stars and dust that gradually grew larger over time. Either scenario requires a fundamental shift in our understanding of how the universe came to be.

One way to confirm the team's finding and alleviate any remaining concerns would be to take a spectrum image of the massive galaxies. That would provide the team data on the true distances, and also the gasses and other elements that made up the galaxies. The team could then use the data to model a clearer of picture of what the galaxies looked like, and how massive they truly were. A spectrum will immediately tell us whether or not these things are real. 

 Ivo Labbe, A population of red candidate massive galaxies ~600 Myr after the Big Bang, Nature (2023). DOI: 10.1038/s41586-023-05786-2. www.nature.com/articles/s41586-023-05786-2

Study finds 'forever chemicals' disrupt key biological processes

A team of researchers  found that exposure to a mixture of synthetic chemicals found widely in the environment alters several critical biological processes, including the metabolism of fats and amino acids, in both children and young adults. The disruption of these biological processes is connected to an increased risk of a very broad range of diseases, including developmental disorders, cardiovascular disease, metabolic disease and many types of cancer.

Known as per- and polyfluoroalkyl substances, or PFAS, these man-made chemicals are used in a wide range of consumer and industrial products. PFAS are sometimes called "forever chemicals" because they break down very slowly and accumulate in the environment and human tissue.

Although individual PFAS are known to increase the risk of several types of disease, this study, published February 22 in Environmental Health Perspectives, is the first to evaluate which biological processes are altered by exposure to a combination of multiple PFAS, which is important because most people carry a mixture of the chemicals in their blood.

In this new study, it was found that exposure to a combination of PFAS not only disrupted lipid and amino acid metabolism but also altered thyroid hormone function.

Another important finding was the fact that exposure to a mixture of PFAS, rather than a single chemical of this type, drove the disruption of these biological processes. This finding was consistent across the two cohorts, even though they had different levels of PFAS exposure.

Metabolic signatures of youth exposure to mixtures of per- and polyfluoroalkyl 2 substances: A multi-cohort study, Environmental Health Perspectives (2023). DOI: 10.1289/EHP11372

Study shows certain wearable gadgets could interfere with implantable cardiac electronic devices

In this high-tech era, wearable devices such as smartwatches have proven to be invaluable companions for the health conscious. But a new study shows that for a small group of people, some of these electronic fitness gadgets could possibly be risky to their health—even potentially deadly.

This new study  shows that wearable devices such as the Samsung Galaxy watch 4, Fitbit smart scales, or Moodmetric smart rings, among others, have sensing technology that could interfere with cardiac implantable electronic devices (CIEDs) such as pacemakers, implantable cardioverter defibrillators (ICDs), and cardiac resynchronization therapy (CRT) devices.

This study raises a red flag. Researchers  have done this work in simulations and benchtop testing following Food and Drug Administration accepted guidelines, and these gadgets interfere with the correct functioning of the CIEDs they tested. These results call for future clinical studies evaluating the translation of their findings to patients wearing CIEDs and using these wearable devices.

Part 1

Certain fitness and wellness trackers could pose serious risks for people with cardiac implantable electronic devices (CIEDs) such as pacemakers, implantable cardioverter defibrillators (ICDs), and cardiac resynchronization therapy (CRT) devices. Credit: Heart Rhythm

But after conducting comprehensive testing of bioimpedance on three cardiac CRT devices from manufacturers Medtronic, Boston Scientific, and Abbott, Sanchez Terrones' team learned the slight electrical currents from these wearable gadgets can interfere and sometimes confuse cardiac implantable devices into operating incorrectly.

In the case of a pacemaker, which sends small electrical impulses to the heart when it is beating too slowly, the bioimpedance's tiny electrical current could trick the heart into thinking it is beating fast enough, preventing the pacemaker from doing its job when it is supposed to.

Safety evaluation of smart scales, smart watches, and smart rings with bioimpedance technology shows evidence of potential interference in cardiac implantable electronic devices, Heart Rhythm (2023). DOI: 10.1016/j.hrthm.2022.11.026

Part 2

Anti-dust tech paves way for self-cleaning surfaces

Dust is a common fact of life, and it's more than just a daily nuisance—it can get into machinery and equipment, causing loss of efficiency or breakdowns.

Researchers  developed a new method to keep dust from sticking to surfaces. The result is the ability to make many types of materials dust resistant, from spacecraft to solar panels to household windows. They demonstrated  a surface that can clean itself. Particulates aren't able to stick to the surface, so they come off using just the force of gravity.

In tests, the researchers piled lunar dust on top of their engineered surfaces and then turned each surface on its side. The result: Only about 2% of the surface remained dusty, compared with more than 35% of a similarly smooth surface.

The researchers said the discovery boils down to things the human eye can't detect. In the experiments, the team altered the geometry of flat surfaces to create a tightly packed nanoscale network of pyramid-shaped structures. These sharp, angular structures make it difficult for the dust particles to stick to the material, instead sticking to one another and rolling off the material via gravity.

These structures provide a passive solution, meaning they don't require any extra energy or materials to remove dust. Compare that with more active solutions such as a car windshield that requires the use of windshield wipers and wiper fluid to clean off dust.

Samuel S. Lee et al, Engineering large-area anti-dust surfaces by harnessing interparticle forces, ACS Applied Materials & Interfaces (2023). DOI: 10.1021/acsami.2c19211. pubs.acs.org/doi/10.1021/acsami.2c19211

Spinal cord stimulation shown to instantly improve arm mobility after stroke

Neurotechnology that stimulates the spinal cord instantly improves arm and hand mobility, enabling people affected by moderate to severe stroke to conduct their normal daily activities more easily, report researchers.

A pair of thin metal electrodes resembling strands of spaghetti implanted along the neck engage intact neural circuits, allowing stroke patients to fully open and close their fist, lift their arm above their head or use a fork and knife to cut a piece of steak for the first time in years.

They discovered that electrical stimulation of specific spinal cord regions enables patients to move their arm in ways that they are not able to do without the stimulation. Perhaps even more interesting, they found that after a few weeks of use, some of these improvements endure when the stimulation is switched off, indicating exciting avenues for the future of stroke therapies.

Spinal cord stimulation technology uses a set of electrodes placed on the surface of the spinal cord to deliver pulses of electricity that activate nerve cells inside the spinal cord. This technology is already being used to treat high-grade, persistent pain. Additionally, multiple research groups around the world have shown that spinal cord stimulation can be used to restore movement to the legs after spinal cord injury.

But the unique dexterity of the human hand, combined with the wide range of motion of the arm at the shoulder and the complexity of the neural signals controlling the arm and hand, add a significantly higher set of challenges.

Following years of extensive preclinical studies involving computer modeling and animal testing in macaque monkeys with partial arm paralysis, researchers were cleared to test this optimized therapy in humans.

The sensory nerves from the arm and hand send signals to motor neurons in the spinal cord that control the muscles of the limb.

By stimulating these sensory nerves, one can amplify the activity of muscles that have been weakened by stroke. Importantly, the patient retains full control of their movements: The stimulation is assistive and strengthens muscle activation only when patients are trying to move.

In a series of tests adapted to individual patients, stimulation enabled participants to perform tasks of different complexity, from moving a hollow metal cylinder to grasping common household objects, such as a can of soup, and opening a lock. Clinical assessments showed that stimulation targeting cervical nerve roots immediately improves strength, range of movement and function of the arm and hand.

Unexpectedly, the effects of stimulation seem to be longer-lasting than scientists originally thought and persisted even after the device was removed, suggesting it could be used both as an assistive and a restorative method for upper limb recovery. Indeed, the immediate effects of the stimulation enable administration of intense physical training that, in turn, could lead to even stronger long-term improvements in the absence of the stimulation.

Moving forward, researchers continue to enroll additional trial participants to understand which stroke patients can benefit most from this therapy and how to optimize stimulation protocols for different severity levels.

Marco Capogrosso, Epidural stimulation of the cervical spinal cord for post-stroke upper-limb paresis, Nature Medicine (2023). DOI: 10.1038/s41591-022-02202-6. www.nature.com/articles/s41591-022-02202-6

Human height remained unchanged for 2,000 years in Milan, finds study

A study covering 2,000 years of male and female adult statures in Milan, Italy, has been published in the journal Scientific Reports, illustrating a stable environmental influence on height.

Human height depends on an interplay between genetics and environmental factors like fetal health, childhood nutrition, disease exposures, as well as environmental epigenetic factors that can reach back generations. While genetics alone may determine how tall a person could become, the environment they are born into plays a significant role in how much of that genetic growth potential is realized. Typically when we look around the world, we see that as health and nutrition have become more reliable since the industrial revolution, humans have reached increasingly greater heights.

In past studies, population stature has been linked to environmental factors. Human height dramatically reduced during the switch from hunter-gatherers to more agricultural societies. Human height has been slowly increasing since then, occasionally being shown to wax and wane with times of sustained prosperity, wars, famines, climate change, and exposure to plague.

In the study, researchers analysed 549 skeletal remains from 13 different sites, all within Milan. The remains all came from necropolises dedicated to the less wealthy classes of Milanese society. They were assigned to one of five historical periods: Roman Era (first–fifth centuries AD), Early Middle Ages (sixth–tenth centuries AD), Late Middle Ages (eleventh–fifteenth centuries AD), Modern Era (sixteenth–eighteenth centuries AD) and Contemporary Era (nineteenth–twentieth centuries AD).

About 100 individuals were assessed for each era, split between male and female. Stature was estimated, mostly using femur bones, according to a well-established forensic regression formula. Individual female heights ranged from 143.5 to 177.6 cm, with a mean of 157.8 cm (about 5'2''). Males ranged from 152.0 to 195.4 cm, with a mean of 168.5 cm (5'6''). There was no significant change in average heights when comparing the historical periods.

By focusing their study on a single geographic location with similar urban and socioeconomic characteristics, researchers were able to remove biases that might arise in studies of multiple populations with distinct environmental influences. With such a homogenous environment, external forces on population height, like wars, plagues, or climate, should have been obvious. Surprisingly, there were no significant fluctuations seen in the statures. Suggesting to the study authors that city life in Milan has provided a stable environment for thousands of years, even for its lowest-income inhabitants.

 Lucie Biehler-Gomez et al, The diachronic trend of female and male stature in Milan over 2000 years, Scientific Reports (2023). DOI: 10.1038/s41598-023-28406-5

**

Scientists unlock key to drought-resistant wheat plants with longer roots

Growing wheat in drought conditions may be easier in the future, thanks to new genetic research.

An international team of scientists found that the right number of copies of a specific group of genes can stimulate longer root growth, enabling wheat plants to pull water from deeper supplies. The resulting plants have more biomass and produce higher grain yield, according to a paper published in the journal Nature Communications.

The research provides novel tools to modify wheat root architecture to withstand low water conditions.

Roots play a very important role in plants. The root absorbs the water and the nutrients to support plants' growth. This finding is a useful tool to engineer root systems to improve yield under drought conditions in wheat. 

Much has been done to improve wheat production but losses from water stress can erase other improvements. Plants that can adapt to low water conditions but have increased yield will be key to growing enough food for a growing population in the face of global warming.

Until now, little has been known about the genes that affect the root structure of wheat. The discovery of the gene family—known as OPRIII—and that different copies of these genes affect root length is a significant step.

The duplication of the OPRIII genes results in increased production of a plant hormone called Jasmonic acid that causes, among other processes, the accelerated production of lateral roots. Different dosages of these genes can be used to obtain different roots.

To get longer roots, the team of researchers used CRISPR gene editing technology to eliminate some of the OPRIII genes that were duplicated in wheat lines with shorter roots. By contrast, increasing the copies of these genes caused shorter and more branched roots. But inserting a rye chromosome, which result in decreased OPRIII wheat genes, caused longer roots.

Fine-tuning the dosage of the OPRIII genes can allow us to engineer root systems that are adapted to drought, to normal conditions, to different scenarios.

Knowing the right combination of genes means researchers can search for wheat varieties that have those natural variations and breed for release to growers planting in low-water environments.

Gilad Gabay et al, Dosage differences in 12-OXOPHYTODIENOATE REDUCTASE genes modulate wheat root growth, Nature Communications (2023). DOI: 10.1038/s41467-023-36248-y

Head injuries could be a risk factor for developing brain cancer

Cancer Researchers have provided important molecular understanding of how injury may contribute to the development of a relatively rare but often aggressive form of brain tumor called a glioma.

Previous studies have suggested a possible link between head injury and increased rates of brain tumors, but the evidence is inconclusive. The present work now identified a possible mechanism to explain this link, implicating genetic mutations acting in concert with brain tissue inflammation to change the behaviour of cells, making them more likely to become cancerous. Although this study was largely carried out in mice, it suggests that it would be important to explore the relevance of these findings to human gliomas.

Gliomas are brain tumors that often arise in neural stem cells. More mature types of brain cells, such as astrocytes, have been considered less likely to give rise to tumors. However, recent findings have demonstrated that after injury astrocytes can exhibit stem cell behavior again.

Researchers  therefore set out to investigate whether this property may make astrocytes able to form a tumour following brain trauma using a pre-clinical mouse model.

Part 1

Young adult mice with brain injury were injected with a substance which permanently labeled astrocytes in red and knocked out the function of a gene called p53—known to have a vital role in suppressing many different cancers. A control group was treated the same way, but the p53 gene was left intact. A second group of mice was subjected to p53 inactivation in the absence of injury.

Normally astrocytes are highly branched—they take their name from stars—but what we found was that without p53 and only after an injury the astrocytes had retracted their branches and become more rounded. They weren't quite stem cell-like, but something had changed. So scientists let the mice age, then looked at the cells again and saw that they had completely reverted to a stem-like state with markers of early glioma cells that could divide.

This suggested that mutations in certain genes synergized with brain inflammation, which is induced by acute injury and then increases over time during the natural process of aging to make astrocytes more likely to initiate a cancer. Indeed, this process of change to stem-cell like behavior accelerated when they injected mice with a solution known to cause inflammation.

The team then looked for evidence to support their hypothesis in human populations. They consulted electronic medical records of more than 20,000 people who had been diagnosed with head injuries, comparing the rate of brain cancer with a control group, matched for age, sex and socioeconomic status.

They found that patients who experienced a head injury were nearly four times more likely to develop a brain cancer later in life, than those who had no head injury. It is important to keep in mind that the risk of developing a brain cancer is overall low, estimated at less than 1% over a lifetime, so even after an injury the risk remains modest.

We know that normal tissues carry many mutations which seem to just sit there and not have any major effects. These new  findings suggest that if on top of those mutations, an injury occurs, it creates a synergistic effect.

In a young brain, basal inflammation is low so the mutations seem to be kept in check even after a serious brain injury. However, upon aging, the mouse work suggests that inflammation increases throughout the brain but more intensely at the site of the earlier injury. This may reach a certain threshold after which the mutation now begins to manifest itself.

Simona Parrinello, Injury primes mutation bearing astrocytes for dedifferentiation in later life, Current Biology (2023). DOI: 10.1016/j.cub.2023.02.013. www.cell.com/current-biology/f … 0960-9822(23)00152-5

Part 2

How birds got their wings

Modern birds capable of flight all have a specialized wing structure called the propatagium without which they could not fly. The evolutionary origin of this structure has remained a mystery, but new research suggests it evolved in nonavian dinosaurs. The finding comes from statistical analyses of arm joints preserved in fossils and helps fill some gaps in knowledge about the origin of bird flight.

How scientists hauling logs on their heads may have solved a Chaco Canyon mystery!

Why did researchers carry a log weighing more than 130 pounds for 15 miles? Their feat of endurance could reveal new information about how ancient peoples hauled more than 200,000 heavy timbers to a site in the modern-day Southwest called Chaco Canyon.

In a new study, several researchers reenacted a small part of a trek that people in the Southwest United States may have made more than 1,000 years ago.

They described their experiment Feb. 22 in the Journal of Archaeological Science: Reports.

This is also done by sherpas in Nepal.

The researchers  they were hoping to solve an archaeological mystery that has perplexed researchers for decades: How did ancient peoples transport more than 200,000 heavy construction timbers over 60 miles to a famous site in the Southwest called Chaco Canyon?

The team's findings show that the key to this testament to human labor may have been simple devices called tumplines. These straps, which sherpas, or native mountain peoples of Nepal, still widely use today, loop over the top of the head. They help porters to support weight using the bones of their neck and spine rather than their muscles. Archaeological evidence suggests that ancient peoples in the Southwest employed tumplines woven from yucca plants to transport everyday items like food and water.

Tumplines allow one to carry heavier weights over larger distances without getting fatigued.

Chaco Canyon sits near the border between New Mexico and Colorado. Thousands of people, the ancestors of today's Diné, or Navajo, and Pueblo peoples, may have lived there from around A.D. 850 to 1200. They built "Great Houses," which were as much as four stories tall and contained hundreds of rooms.

But how this society got its construction supplies has been a long-standing mystery. Human porters would have needed to carry 16-foot-long wooden beams to Chaco Canyon by foot—following a network of ancient roads to sites like the Chuska Mountains to the west.

The team's findings open up a new understanding of the day-to-day lives of the people who shaped the Southwest more than a thousand years ago.

the team's results show that supplying Chaco Canyon with goods may not have been as back-breaking an undertaking as archaeologists once assumed.

As these guys showed, you don't have to be super trained to carry a log.

ames A. Wilson et al, Were timbers transported to Chaco using tumplines? A feasibility study, Journal of Archaeological Science: Reports (2023). DOI: 10.1016/j.jasrep.2023.103876

Combining forces to advance ocean science

All Living Cells Could Have The Molecular Machinery For a 'Sixth Sense'

Every animal on Earth may house the molecular machinery to sense magnetic fields, even those organisms that don't navigate or migrate using this mysterious 'sixth sense'.

Scientists working on fruit flies have now identified a ubiquitous molecule in all living cells that can respond to magnetic sensitivity if it is present in high enough amounts or if other molecules assist it.

The new findings suggest that magnetoreception could be much more common in the animal kingdom than we ever knew. If researchers are right, it might be an astonishingly ancient trait shared by virtually all living things, albeit with differing strengths.

That doesn't mean all animals or plants can actively sense and follow magnetic fields, but it does suggest that all living cells might, including ours.

How we sense the external world, from vision, hearing through to touch, taste, and smell, are well understood.

But by contrast, which animals can sense and how they respond to a magnetic field remains unknown. This study has made significant advances in understanding how animals sense and respond to external magnetic fields - a very active and disputed field.

Magnetoreception might sound like magic to us, but plenty of fish, amphibians, reptiles, birds, and other mammals in the wild can sense the tug of Earth's magnetic field and use it to navigate space.

Because this force is essentially invisible to our species, it took a remarkably long time for scientists to notice it.

Only in the 1960s did scientists show that bacteria can sense magnetic fields and orient themselves in relation to those fields; in the 1970s, we found that some birds and fish follow Earth's magnetic field when migrating.

Part 1

Even to this day, however, it's still unclear how so many animals achieve these incredible feats of navigation.

In the 1970s, scientists suggested that this magnetic-compass sense could involve radical pairs, molecules with unpaired outer shell electrons that form a pair of entangled electrons whose spins are altered by the Earth's magnetic field.

Twenty-two years later, that study's lead author co-authored a new paper proposing a specific molecule in which the radical pairs could be formed.

This molecule – a receptor in the retina of migrating birds called a cryptochrome – can sense light and magnetism, and it seems to work through quantum entanglement.

In basic terms, when a cryptochrome absorbs light, the energy triggers one of its electrons, pushing it to occupy one of two spinning states, each of which is differently influenced by Earth's geomagnetic field.

Cryptochromes have been a leading explanation for how animals sense magnetic fields for two decades, but now researchers at the Universities of Manchester and Leicester have identified another candidate.

Manipulating the genes of fruit flies, the team found that a molecule called Flavin Adenine Dinucleotide (FAD), which usually forms a radical pair with cryptochromes, is actually a magnetoreceptor in and of itself.

This basic molecule is found at differing levels in all cells, and the higher the concentration, the more likely it is to impart magnetic sensitivity, even when cryptochromes are lacking.

In fruit flies, for instance, when FAD is stimulated by light, it generates a radical pair of electrons that are responsive to magnetic fields.

However, when cryptochromes are present alongside FADs, a cell's sensitivity to magnetic fields increases. The findings suggest that cryptochromes are not as essential as we thought for magnetoreception.

That shows cells can, at least in a laboratory, sense magnetic fields through other ways."

The discovery could help explain why human cells show sensitivity to magnetic fields in the lab. The form of cryptochrome present in the cells of our species' retina has proved capable of magnetoreception at a molecular level when expressed in fruit flies.

However, this doesn't mean humans utilize that function, nor is there evidence that cryptochrome guides our cells to line up along magnetic fields in the lab.

Tissue engineering: Developing bioinspired multi-functional tendon-mimetic hydrogels

Materials scientists work to develop advanced biological materials for medical devices and tissue engineering platforms to emulate natural biological tissue architectures via materials engineering. However, the natural tissue architecture has a variety of characteristics that are difficult to synthetically replicate. The architecture of tendons relies on the load-bearing capacities of the musculoskeletal system to provide biophysical cues that translate into cellular behaviors via interfacial interactions. In the past decade, researchers had devoted extensive research efforts to engineer tendon-mimetic materials with high structural anisotropy.

In a new report now published in Science Advances,  a research team in physics, mechanical engineering, electrical and electronic engineering reported the development of multifunctional tendon-mimetic hydrogels by assembling aramid nanofiber composites. 

The anisotropic composite hydrogels (ACH) contained stiff nanofibers and soft polyvinyl alcohol moieties to mimic biological interactions that typically occur between collagen fibers and proteoglycans  in tendons. The team was bioinspired by natural tendons to develop hydrogels with a high elastic modulus, strength and fracture toughness.

The researchers biofunctionalized these material surfaces with bioactive molecules to present biophysical cues to impart behavioral similarities to those of cell attachment. Additionally, the soft bioelectronic components integrated on the hydrogels facilitated a variety of physiological benefits. Based on the outstanding functionality of the tendon-mimetics, the team envisioned broader applications of the materials in advanced tissue engineering to form implantable prosthetics for human-machine interactions.

Mingze Sun et al, Multifunctional tendon-mimetic hydrogels, Science Advances (2023). DOI: 10.1126/sciadv.ade6973

Jeong-Yun Sun et al, Highly stretchable and tough hydrogels, Nature (2012). DOI: 10.1038/nature11409

Study finds common artificial sweetener linked to higher rates of heart attack and stroke

New research showed that erythritol, a popular artificial sweetener, is associated with an increased risk of heart attack and stroke. Findings were published today in Nature Medicine.

Researchers studied more than 4,000 people in the U.S. and Europe and found those with higher blood erythritol levels were at elevated risk of experiencing a major adverse cardiac event such as heart attack, stroke or death. They also examined the effects of adding erythritol to either whole blood or isolated platelets, which are cell fragments that clump together to stop bleeding and contribute to blood clots. Results revealed that erythritol made platelets easier to activate and form a clot. Pre-clinical studies confirmed ingestion of erythritol heightened clot formation.

Artificial sweeteners, such as erythritol, are common replacements for table sugar in low-calorie, low-carbohydrate and "keto" products. Sugar-free products containing erythritol are often recommended for people who have obesity, diabetes or metabolic syndrome and are looking for options to help manage their sugar or calorie intake. People with these conditions also are at higher risk for adverse cardiovascular events like heart attack and stroke.

Erythritol is about 70% as sweet as sugar and is produced through fermenting corn. After ingestion, erythritol is poorly metabolized by the body. Instead, it goes into the bloodstream and leaves the body mainly through urine. The human body creates low amounts of erythritol naturally, so any additional consumption can accumulate.

Measuring artificial sweeteners is difficult and labeling requirements are minimal and often do not list individual compounds. Erythritol is "Generally Recognized As Safe (GRAS)" by the FDA, which means there is no requirement for long-term safety studies.

The authors note the importance of follow-up studies to confirm their findings in the general population. The study had several limitations, including that clinical observation studies demonstrate association and not causation.

This study shows that when participants consumed an artificially sweetened beverage with an amount of erythritol found in many processed foods, markedly elevated levels in the blood are observed for days—levels well above those observed to enhance clotting risks. It is important that further safety studies are conducted to examine the long-term effects of artificial sweeteners in general, and erythritol specifically, on risks for heart attack and stroke, particularly in people at higher risk for cardiovascular disease.

 Stanley Hazen, The artificial sweetener erythritol and cardiovascular event risk, Nature Medicine (2023). DOI: 10.1038/s41591-023-02223-9. www.nature.com/articles/s41591-023-02223-9

Tiny environmental plastic particles in mom's food reach unborn children

Nanoscale plastic particles like those that permeate most food and water pass from pregnant rats to their unborn children and may impair fetal development, according to a  study that suggests the same process happens in humans.

Erosion chips microscopic particles off the billions of tons of plastics that are exposed to the elements in the environment. These particles mix with the food we eat and the air we breathe. A typical person ingests a credit card's worth of them every week.

Previous studies in pregnant laboratory animals have found adding these plastics to food impairs their offspring in numerous ways, but those studies didn't determine whether mothers passed the plastics to their children in utero.

The study provided specially marked nanoscale plastics to five pregnant rats. Subsequent imaging found that these nanoplastic particles permeated not only their placentas but also the livers, kidneys, hearts, lungs and brains of their offspring.

These findings demonstrate that ingested nanoscale polystyrene plastics can breach the intestinal barrier of pregnant mammals, the maternal-fetal barrier of the placenta and all fetal tissues. Future studies will investigate how different types of plastics cross cell barriers, how plastic particle size affects the process and how plastics harm fetal  development, the researchers said.

 Chelsea M. Cary et al, Ingested Polystyrene Nanospheres Translocate to Placenta and Fetal Tissues in Pregnant Rats: Potential Health Implications, Nanomaterials (2023). DOI: 10.3390/nano13040720

Researchers discover the mechanism by which tumor cells become resistant to chemotherapy in colorectal cancer

 Platinum-based chemotherapy, which is used to treat advanced colorectal cancer, accumulates in the healthy cells surrounding the cancer cells and, as a result, can reduce tumor sensitivity to treatment. This is demonstrated by a study published in the journal Nature Communications.

 A large number of cancer patients are treated with platinum-based therapy. However, many tumors are capable of developing resistance to treatment. In this study, the researchers examined tumor samples from patients and pre-clinical models of colorectal cancer to better understand the resistance to platinum-based therapy. They observed that platinum accumulates prominently in the healthy cells that surround the cancer cells, particularly in fibroblasts, the cells that contribute to tissue formation. Furthermore, this accumulation persists for more than two years after treatment has been completed. This discovery was made using techniques developed in geology and applied to biological samples.

The effect of platinum on fibroblasts
The researchers were able to demonstrate how the accumulation of platinum in the fibroblasts induced the activation of certain genes associated with a poor response to chemotherapy and tumor progression. Among them, the TGF-β protein redirected these fibroblasts to support cancer cells aggressiveness and resistance to treatment. 

There are currently no predictive biomarkers of benefit from chemotherapy in colorectal cancer. The analysis of about thirty patients before and after chemotherapy presented in this study reveals that periostin levels are an indicator of TGF-β activity in fibroblasts and serve as a robust marker of response to chemotherapy. Indeed, treatment benefit was significantly reduced in patients with elevated periostin levels before and/or after chemotherapy. Accordingly, chemotherapy was found to be less effective in tumors with high levels of periostin in pre-clinical colorectal cancer models.

The researchers are now working on developing a novel approach to improve the efficacy of chemotherapy in colorectal cancer.

This study is an important step toward understanding why chemotherapy does not work the same way in all cancer patients, and how to prevent or reverse resistance. This work is also essential in demonstrating that cancer treatment must take into account not only the cancer cells but also the healthy cells in the tumor. The next critical step will be to develop pharmacological strategies that act on the cancer cell and modulate the microenvironment in favor of tumor elimination.

 Jenniffer Linares et al, Long-term platinum-based drug accumulation in cancer-associated fibroblasts promotes colorectal cancer progression and resistance to therapy, Nature Communications (2023). DOI: 10.1038/s41467-023-36334-1

Your pets leaking information about you? Yes, considering this:

Pet and animal-related apps are creating cybersecurity risks to their owners, new research has shown.

While being able to trace your cat and dog may be an attractive benefit to many pet owners as it can provide peace of mind, allowing a third party to track your movements may be much less attractive.

Computer scientists 

have exposed multiple security and privacy issues by evaluating 40 popular Android apps for pets and other companion animals as well as farm animals. The results show that several of these apps are putting their users at risk by exposing their login or location details. Password vulnerability was one of the areas exposed by the team. They identified three applications that had the user's login details visible in plain text within non-secure HTTP traffic. This means that anyone is able to observe the internet traffic of someone using one of these apps and will be able to find out their login information. In addition to login information, two of the apps also showed user details, such as their location, that may enable someone to gain access to their devices and risk a cyber-attack. Another area of concern identified in the study was the use of trackers. All but four of the applications were found to feature some form of tracking software. A tracker gathers information on the person using the application, on how they use it, or on the smartphone being used. The scientists also warn that the apps perform very poorly in terms of notifying the user of their privacy policy. Their analysis shows that 21 of the apps are tracking the user in some way before the user even has a chance to consent to this, violating current data protection regulations.

Scott Harper et al, Security and Privacy Concerns of Pet Tech Users, Proceedings of the 12th International Conference on the Internet of Things (2023). DOI: 10.1145/3567445.3571102

Scot Harper et al, Are Our Animals Leaking Information About Us? Security and Privacy Evaluation of Animal-related Apps, IEEE European Symposium on Security and Privacy Workshops (EuroS&PW) (2022). DOI: 10.1109/EuroSPW55150.2022.00012

'Dead zone' within tumor promotes cancer spread, helped by a protein secreted by cancer cells

A tumor's necrotic core contains factors that appear to promote metastasis, or the seeding of tumors cells throughout the body, according to a new study in rats by researchers. 

Tumor necrotic cores are a fairly common phenomenon, but they haven't been linked to cancer metastasis until recently. This research put together observations other people have made into the specific context of breast cancer metastasis. It shows a link between necrosis, circulating tumour cells and cancer metastasis.

Necrotic cores are tumors that are dying from the inside out, and they make for a perfect environment for cancer to spread.

Dead zones of tumors have leaky blood vessels, hypoxia or low levels of oxygen and the recruitment of immune cells, some of which have been shown to help cancer cells spread. What the researchers think is happening is that the necrotic core is mostly a dead zone, but it also has some surviving tumour cells that help the cancer disseminate in the body.

Surgeons, pathologists, radiologists, clinicians and researchers often come across necrotic cores in their line of work and they're usually not a good sign.

Necrosis is a clinical finding seen in aggressive tumors that grow quickly. 

When doctors see it in a patient's biopsy, it means this is a dangerous tumor that needs to be treated aggressively. But necrosis isn't only something seen in large, late-stage tumours. It can happen in early-stage and small tumours too.

Part1

**

Researchers developed a new rat model of breast cancer metastasis to study the necrotic core of tumors. Over several weeks, they tracked the progression of circulating tumor cells (CTCs), which is a measure of whether the cancer cells are escaping into the bloodstream to spread throughout the body. They found zero CTCs at the first two time points examined (after 13 and 17 days), but that changed by the fourth time point at 27 days.

Suddenly, they found hundreds of CTCs. They linked the increase in cancer cells with when the primary tumour developed a large central area of necrosis.

Further investigation showed a stark difference in gene expression between the necrotic and the non-necrotic regions of the tumour.

Scientists  found that a gene which encodes angiopoietin-like 7, a secreted protein, was the most enriched tumour-derived gene in the necrotic and regions next to necrotic regions of the tumour.

The researchers found that this single protein, angiopoietin-like-7, remodels the tumour microenvironment, somehow encouraging the tumour cells to grow past their nutrient limits, undergo necrosis and start spreading to other parts of the body.

They then did experiments to see how controlling the protein would impact necrosis.

When they suppressed the expression of this protein in the tumours, there was a dramatic reduction of necrotic tumour area. Suppression of angiopoietin-like 7, or A-7, also reduced circulating tumour cells to almost zero and reduced distant metastases and dilated, large blood vessels.

This research not only showed A-7 regulates the development of central necrosis in the primary tumour, but also the development of dilated blood vessels which could be helping the dissemination of circulating tumor cells and metastasis.

Beyond the surprise of such an important mechanism to necrosis, these findings unveiled the potential for a new targeted treatment for patients.

 Yamamoto, Ami et al, Metastasis from the tumor interior and necrotic core formation are regulated by breast cancer-derived angiopoietin-like 7, Proceedings of the National Academy of Sciences (2023). DOI: 10.1073/pnas.2214888120. doi.org/10.1073/pnas.2214888120

Part 2

Breathing is going to get tougher as hotter temps mean more air pollution

 When global temperatures increase by 4°C, harmful plant emissions and dust will also increase by as much as 14%, according to new  research.

The research does not account for a simultaneous increase in human-made sources of air pollution, which has already been predicted by other studies.

Human beings can change their behaviour. We can switch to electric cars. But that may not change air pollution from plants or dust.

Details of the degradation in future air quality from these natural sources have now been published in the journal Communications Earth & Environment. About two-thirds of the future pollution is predicted to come from plants.

All plants produce chemicals called biogenic volatile organic compounds, or BVOCs. The smell of a just-mowed lawn, or the sweetness of a ripe strawberry, those are BVOCs. Plants are constantly emitting them. 

On their own, BVOCs are benign. However, once they react with oxygen, they produce organic aerosols. As they're inhaled, these aerosols can cause infant mortality and childhood asthma, as well as heart disease and lung cancer in adults. There are two reasons plants increase BVOC production: increases in atmospheric carbon dioxide and increases in temperatures. Both of these factors are projected to continue increasing. To be clear, growing plants is a net positive for the environment. They reduce the amount of carbon dioxide in the atmosphere, which helps control global warming.

BVOCs from small gardens will not harm people. It's the large-scale increase in carbon dioxide that contributes to the biosphere increasing BVOCs, and then organic aerosols.

The second-largest contributor to future air pollution is likely to be dust from the Saharan desert. In scientists' models, an increase in winds is projected to loft more dust into the atmosphere. 

Part1

As the climate warms, increased Saharan dust is likely to get blown around the globe, with higher levels of dust in Africa, the eastern U.S., and the Caribbean. Dust over Northern Africa, including the Sahel and the Sahara, is likely to increase due to more intense West African monsoons.

Both organic aerosols and dust, as well as sea salt, black carbon, and sulfate, fall into a category of airborne pollutants known as PM_2.5, because they have a diameter of 2.5 micrometers or less. The increase in naturally sourced PM_2.5 pollution increased, in this study, in direct proportion to CO₂ levels.

The more we increase CO₂, the more PM_2.5 we see being put into the atmosphere, and the inverse is also true. The more we reduce, the better the air quality gets.

For example, if the climate warms only 2°C, the study found only a 7% increase in PM_2.5. All of these results only apply to changes found in air quality over land, as the study is focused on human health impacts.

The researchers hope the potential to improve air quality will inspire swift and decisive action to decrease CO₂ emissions. Without it, temperatures may increase 4°C by the end of this century, though it's possible for the increase to happen sooner.

If things go on like this, in the future, make sure you get an air purifier. 

James Gomez et al, The projected future degradation in air quality is caused by more abundant natural aerosols in a warmer world, Communications Earth & Environment (2023). DOI: 10.1038/s43247-023-00688-7

Part2

**

Child didn’t die of global bird-flu variant

An 11-year-old girl in Cambodia who died after being infected with avian influenza A (H5N1) had a different variant from that causing mass deaths in birds globally. The strain she was carrying is endemic to the region, and last infected people in Cambodia about a decade ago. Investigations are under way into why the virus has spilled over from birds to people again. “Hopefully this is an isolated incident, but it could be indicative of a larger issue,” says virologist Erik Karlsson at the Pasteur Institute of Cambodia in Phnom Penh.

---

Hints that flu arose underwater

Corals, sturgeon and other aquatic creatures harbour signs of infection by influenza and its distant relatives. A genetic analysis reveals that the virus family probably originated hundreds of millions of years ago in primordial aquatic ... that evolved well before the first fishes. It’s not clear whether influenza moved onto land with early terrestrial vertebrates, or jumped from sea to land more recently.

----

The molecule that kickstarted life

For more than 15 years, scientists have been on a quest: create a functional ‘protoribosome’, a reconstructed version of the protein-building machine that many t.... The modern ribosome is a key ingredient of life as we know it because it translates genetic information into proteins. At its heart sits a small RNA pocket that some think might be closest to what the very first ribosome looked like. Now, there’s proof that some reconstructed protoribosome-like RNAs can link amino acids — the first step to making proteins. Some scientists say there are other ways for proteins to emerge, without a ribosome. But others are already thinking about repurposing these simple machines to manufacture new kinds of biomolecule.

Satellite images show coastal algae blooms have grown larger over past two decades

A team of Earth scientists affiliated with multiple institutions has found that coastal algae blooms (also known as phytoplankton blooms) have been getting bigger over the past couple of decades. In their study, published in the journal Nature, the group analyzed satellite data supplied to them by NASA to compare the size and frequency of algae blooms along the coasts of the world's continents.

Algae blooms are accumulations of algae in a shared area atop a water source. Algae are aquatic plants that contain chlorophyll, but have no leaves, roots, stems, vascular tissue or flowers. They vary in size, from single-celled species to large strands of seaweed. They can have different colors and can inhabit either fresh or saltwater systems. Algae blooms grow larger as their food source grows, particularly nitrogen and phosphorus, both of which are supplied indirectly through human sources such as fertilizer runoff. Prior research has shown that algae blooms can serve as a food source for some sea creatures, but they can also cause problems, such as carrying and dispersing toxic material. Such toxins have been found to accumulate in ocean networks, sometimes leading to oxygen depletion, which can lead to ocean dead zones. In this new effort, the research team found evidence that algae blooms are getting larger, which suggests fertilizer runoff has been increasing.

The work involved studying satellite images obtained from NASA's Aqua satellite over the years 2003 to 2020. By comparing such blooms over time, they found them to be growing at an increasing rate of 59.2%, globally. They also found that as of 2020, the combined size of all ocean-based algae blooms was 31.47 million km², which, they note, is approximately 8.6% of total ocean surface area.

The researchers also found patterns of increase—the areas where the water temperatures were rising the fastest were the same areas where the algae blooms were growing the fastest. Additionally, they found associations between sea surface temperatures, ocean circulation and the frequency of algae blooms.

'Rivers in the sky' shape African climate

East Africa is much drier than other tropical land regions, including the Amazon and Congo rainforests. The geography of East Africa was always thought to make the region dry and susceptible to drought, but the precise mechanism has been elusive until now. This research demonstrates the east to west river valleys are a crucial factor in the low annual rainfall.

Normally, when we think of valleys and water, we think of the rivers that flow along the ground. In East Africa, deep valleys, such as the Turkana Valley, channel strong winds and create invisible rivers in the sky. These invisible rivers carry millions of tons of water vapor, the key ingredient for rainfall.

New experiments show the valleys affect climate on a continental scale. It can't rain equally everywhere, and the valleys help to sustain high rainfall in the Congo basin, while leaving East Africa prone to drought.

Callum Munday et al, Valley formation aridifies East Africa and elevates Congo Basin rainfall, Nature (2023). DOI: 10.1038/s41586-022-05662-5

**

Social animals should limit individuality to conform with the behaviour of the group, says study

Scientists  have observed that group safety was improved when animals paid attention to the behaviours of each other.

Their findings, accepted for publication in PLoS Computational Biology, reveal that simple social behavioral rules can drive conformity behaviour in groups, eroding consistent behavioural differences shown by individual animals.

Personality suppression may be a common strategy in group-living animals, and in particular, we should tend to see the behaviors of the most adventurous or shy individuals shifting towards what the majority of the group are doing.

The team modeled the behavior of a small group of animals with differing tendencies while performing risky behaviours when traveling away from a safe home site towards a foraging site. They then compared this to their behaviour while completing the same activity in a group.

The group-aware individuals spent longer in the safe space and moved more quickly to the foraging spot, making the mission less dangerous. Groups are usually made up of individuals who are different to each other in the way that they normally behave—these consistent individual differences are what determines the personality of the individual.

This study was based on fish behaviour. 

When faced with a social task,  researchers found that the fish tend to suppress their own behavior, and instead conform with what other fish in the group are doing.

 If individuals pay attention to other group members, this has an overall impact on the efficiency of the group, and demonstrates that simple social behaviors can result in the suppression of individual personalities.

.This suggests that compromise may lie at the heart of many social behaviors across the animal kingdom.

Sean A. Rands et al, Personality variation is eroded by simple social behaviours in collective foragers, PLoS Computational Biology (2023). DOI: 10.1371/journal.pcbi.1010908. journals.plos.org/ploscompbiol … journal.pcbi.1010908 On bioRxiv: DOI: 10.1101/2022.03.21.485155

Scientists push the boundaries of manipulating light at the submicroscopic level

A team of researchers  has shown light can be moved within a distance which is smaller than its own wavelength—a level of unprecedented precision.

Scientists have demonstrated that a beam of light can not only be confined to a spot which is 50 times smaller than its own wavelength, but that also—in a first of its kind—the spot can be moved by miniscule amounts at the point where the light is confined. The detailed findings of their theoretical study are published in the journal Optica.

Confining and controlling light on ever smaller volumes is one of the defining challenges in modern photonics; the science behind the generation, detection and manipulation of light. How tightly the light is confined determines the limits for the observability of nanoparticles, as well as the intensity and the precision of light-based devices. One example is optical tweezers. These are widely used in laboratories around the world in fields such as that of DNA research. They consist of highly focused laser beams that trap, manipulate and move particles with astounding precision. One of the limitations with standard optical tweezers is that lenses cannot focus beams on lengths much smaller than the laser beam's own wavelength, limiting the achievable precision.

By its nature, light is indeed very difficult to localize on a smaller length scale than its wavelength, a critical threshold known as the Abbe limit. However, using a sophisticated model and numerical simulation, scientists have successfully demonstrated a novel approach to localize and dynamically manipulate light at a sub-wavelength scale.

Erika Cortese et al, Real-space nanophotonic field manipulation using non-perturbative light–matter coupling, Optica (2022). DOI: 10.1364/OPTICA.473085

Asteroid lost 1 million kilograms after collision with DART spacecraft

How to stop bird flu becoming a pandemic

After avian influenza killed a girl in Cambodia last week, fears are rising about the virus’s potential to spark a human pandemic. It’s hard to say whether this will actually happen, says veterinary pathologist Thijs Kuiken. Versions of the H5N1 influenza virus have been circulating in birds for about 25 years, but the discovery of a variant that transmits between mink increases the risk that the virus could start spreading in humans. Scientists say it’s important to keep tracking the disease’s spread.... Because drugs and vaccines against H5N1 are already available, a bird flu pandemic would probably be more manageable than COVID-19.

https://www.nature.com/articles/d41586-023-00591-3?utm_source=Natur...

Researchers have discovered a new type of coexistence between algae and fungi

Researchers  have described the symbiotic relationship between fungi and algae.  The coexistence of algae and corticioid basidiomycetes, which are common in temperate forests, has been given a new name: "alcobiosis." Their work has been published in Scientific Reports.

Years ago, during field trips, researchers were repeatedly puzzled to find a layer of green algae where some of the fungal coatings on wood or bark (so-called corticioid fungi) are disturbed. They discovered that this is a close symbiosis of fungi and algae, not a lichen, though, because the fungus does not depend on its alga for nourishment.

The new term introduced by the researchers for this type of coexistence, "alcobiosis," is formed by letters from the three key words: algae, corticioid fungi and symbiosis.

In the course of several years, the team of researchers gathered a large number of samples and performed DNA sequencing of the algal and fungal partners. They discovered that the symbiosis is very common and occurs in a great many corticioid fungi across the class of agaricomycetes. Individual fungal species are usually faithful to a specific algal species from a range of algae described in various alcobioses.

Ensuing physiological measurements of algal activity in alcobioses confirmed that the algae are alive, active and engage heavily in photosynthesis, which proves that they prosper inside fungal tissue. Alcobioses bear a striking resemblance to lichens, but differ from them in that the fungal partner does not depend on its alga for nourishment.

And so the main unknown still is in what way this symbiosis is beneficial for each of the partners.

But this study shows alcobioses as a widespread phenomenon which includes a large number of algae and fungi.

During their research, the authors also discovered that the spread of alcobioses is aided by small gastropods who often feed on corticioid fungi. Their excrements contain viable cells of algae and fungi who give rise to new alcobiotic coating shortly after. This type of reproduction is similar to lichen "isidia" (i.e., specific lichen thallus structures used in vegetative reproduction). Alcobioses are clearly visible to the naked eye and it is easy to distinguish them from similar fungi that do not form this kind of relationship.

Alcobioses are common in urban areas, too. Lyomyces sambuci, pictured here, is abundant on elder bark. Credit: Institute of Botany, Czech Academy of SciencesJan Vondrák et al, Alcobiosis, an algal-fungal association on the threshold of lichenisation, Scientific Reports (2023). DOI: 10.1038/s41598-023-29384-4. www.nature.com/articles/s41598-023-29384-4

Breathtakingly Beautiful Photo Gives an Astronaut's View of an Aurora

For The First Time Ever, Physicists See Molecules Form Through Quantum Tunneling

Chemistry takes effort. Whether it's by raising the temperature, increasing the odds that compatible atoms will collide in a heated smash-up, or increasing the pressure and squeezing them together, building molecules usually demands a certain cost in energy.

Quantum theory does provide a workaround if you're patient. And a team of researchers from the University of Innsbruck in Austria has finally seen the quantum tunneling in action in a world-first experiment measuring the merger of deuterium ions with hydrogen molecules.

Tunneling is a quirk of the quantum universe that makes it seem like particles can pass through obstacles that are ordinarily too hard to overcome.

In chemistry, this obstacle is the energy required for atoms to bond with one another, or with existing molecules.

Yet theory says that, in extremely rare instances, it's possible for atoms in close proximity to 'tunnel' their way through this energy barrier and connect without any effort.

Quantum mechanics allows particles to break through the energetic barrier due to their quantum mechanical wave properties, and a reaction occurs.

Quantum waves are the ghosts that drive the behaviors of objects like electrons, photons, and even entire groups of atoms, blurring their existence before any observation so they sit not in any one precise place but occupy a continuum of possible positions.

This blurring is insignificant for larger objects like molecules, cats, and galaxies. But as we zoom in on individual subatomic particles, the range of possibilities expands, forcing the location states of various quantum waves to overlap.

When that happens, particles have a slight chance of appearing where they have no business being, tunneling into regions that would otherwise require a great deal of force to enter.

One of those regions for an electron might be within the bonding-zone of a chemical reaction, welding together neighboring atoms and molecules without the boom-crash-crush of heat or pressure.

part1

Understanding the role quantum tunneling plays in the building and rearrangements of molecules could have important ramifications in the calculations of energy release in nuclear reactions, such as those involving hydrogen in stars and fusion reactors here on Earth.

While we've modeled this phenomenon for examples involving reactions between a negatively charged form of deuterium – an isotope of hydrogen containing a neutron – and dihydrogen or H₂, proving the numbers experimentally requires a challenging level of precision.

To accomplish this, Wild and his colleagues cooled negative deuterium ions to a temperature that brought them close to a standstill before introducing a gas made of hydrogen molecules.

Without heat, the deuterium ion was far less likely to have the energy required to force hydrogen molecules into a rearrangement of atoms. Yet it also forced the particles into sitting quietly near one another, giving them more time to bond through tunneling.

In their experiment, scientists give possible reactions in the trap about 15 minutes and then determine the amount of hydrogen ions formed. From their number, they can deduce how often a reaction has occurred.

That figure is just over 5 x 10^-20 reactions per second taking place in each cubic centimeter, or around one tunneling event for around every hundred billion collisions. So not a lot. Though the experiment does back up previous modeling, confirming a benchmark that can be used in predictions elsewhere.

Given tunneling plays a fairly important role in a diverse range of nuclear and chemical reactions, much of which is also likely to occur out in the cold depths of space, getting a precise grip on the factors at play gives us a more solid grounding to base our predictions on.

https://www.nature.com/articles/s41586-023-05727-z

part 2

A Rise in Online Shopping Partially to Blame For Recent Spike in Whale Deaths

Our addiction to online shopping is contributing to the recent spike in whale deaths, The New York Times reports.

Since early December, 23 whales have washed up dead along the East Coast, according to data the National Oceanic and Atmospheric Administration provided to The Times. Their deaths are due to a confluence of factors, both environmental and the result of human interference.

NOAA has been tracking an "unusual mortality event" among the Atlantic Coast humpback whale population since 2016, but the recent spike in whale deaths – which has included humpback whales, minke whales, and North Atlantic right whales, which are critically endangered – prompted the NOAA Fisheries to address the crisis during a call with reporters in January.

Lauren Gaches, the agency's public affairs director, said during the call that climate change is partly to blame for the number of whales washing up dead, because warming oceans are causing the fish they eat to move closer to shore.

"We're seeing populations of many marine species adapting by moving into new areas where conditions are more favorable," Gaches said.

"Changing distributions of prey impact larger marine species that depend on them. This can lead to increased interactions with humans as some whales move closer to near-shore habitats."

Which means as some whales seek out prey, they're moving into the path of cargo ships, which have gotten bigger and more plentiful over the past three years.

Part 1

Boat strikes can be deadly for whale populations all over the world The surge in online shopping that began during the pandemic has led to an increase in cargo ships hauling those goods across the Atlantic to the busy Port of New York and New Jersey. Those ships, larger than they were in the past in order to carry more shipping containers, are also taking new routes in an effort to avoid clogging up shipping lanes like in years past, according to The Times. The Port Authority of New York and New Jersey saw a 27 percent increase in volume last year compared to 2019 levels, and shipping traffic along the East Coast has increased as boats have started making down-and-back trips to retrieve empty shipping containers. While NOAA has proposed speed limits, which could give whales time to move out of the way of oncoming ships, the fact remains that whales are always going to follow their food. "When the whales are in these channels, you have to cross your fingers and hope there are no collisions," Paul Sieswerda, executive director of New York City-based research group Gotham Whale, told The Times. Boat strikes can cause internal injuries from the blunt force trauma, and their propellers can inflict large gashes. Two whales that washed up dead along the Atlantic Coast this month were determined to have been struck by vessels, USA Today reported. This isn't the first time experts have raised the alarm about ships harming whale populations. A year ago, scientists began calling for cargo ships to start rerouting in order to protect endangered blue whales that live off the coast of Sri Lanka. Mediterranean Shipping Company, the largest container line in the world, complied with the request, and animal welfare groups said at the time that if other companies followed, it could reduce ship strikes by 95 percent. This article was originally published by Business Insider.

https://www.sciencealert.com/a-rise-in-online-shopping-partially-to...

Part 2

**

Black Hole Mergers

6174 is known as Kaprekar's constant after the Indian mathematician D. R. Kaprekar. This number is renowned for the following rule:

1. Take any four-digit number, using at least two different digits (leading zeros are allowed).
2. Arrange the digits in descending and then in ascending order to get two four-digit numbers, adding leading zeros if necessary.
3. Subtract the smaller number from the bigger number.
4. Go back to step 2 and repeat.

The above process, known as Kaprekar's routine, will always reach its fixed point, 6174, in at most 7 iterations. Once 6174 is reached, the process will continue yielding 7641 – 1467 = 6174. For example, choose 1459:

9541 – 1459 = 8082

8820 – 0288 = 8532

8532 – 2358 = 6174

7641 – 1467 = 6174

The only four-digit numbers for which Kaprekar's routine does not reach 6174 are repdigits such as 1111, which give the result 0000 after a single iteration. All other four-digit numbers eventually reach 6174 if leading zeros are used to keep the number of digits at 4. For numbers with three identical numbers and a fourth number that is one number higher or lower (such as 2111), it is essential to treat 3-digit numbers with a leading zero; for example: 2111 – 1112 = 0999; 9990 – 999 = 8991; 9981 – 1899 = 8082; 8820 – 288 = 8532; 8532 – 2358 = 6174.

6174 (number) - Wikipedia

Hubble’s Inside The Image: V838

Scientists found a way to generate new neurons in the brain

Some areas of the adult brain contain quiescent, or dormant, neural stem cells that can potentially be reactivated to form new neurons. However, the transition from quiescence to proliferation is still poorly understood. A research team  has discovered the importance of cell metabolism in this process and identified how to wake up these neural stem cells and reactivate them.

Biologists succeeded in increasing the number of new neurons in the brain of adult and even elderly mice. These results, promising for the treatment of neurodegenerative diseases, are to be discovered in the journal Science Advances.

Stem cells have the unique ability to continuously produce copies of themselves and give rise to differentiated cells with more specialized functions. Neural stem cells (NSCs) are responsible for building the brain during embryonic development, generating all the cells of the central nervous system, including neurons.

Surprisingly, NSCs persist in certain brain regions even after the brain is fully formed and can make new neurons throughout life. This biological phenomenon, called adult neurogenesis, is important for specific functions such as learning and memory processes. However, in the adult brain, these stem cells become more silent or "dormant" and reduce their capacity for renewal and differentiation.

As a result, neurogenesis decreases significantly with age. Researchers have uncovered a metabolic mechanism by which adult NSCs can emerge from their dormant state and become active again.

They found that mitochondria, the energy-producing organelles within cells, are involved in regulating the level of activation of adult NSCs.

 The mitochondrial pyruvate transporter (MPC), a protein complex discovered eleven years ago, plays a particular role in this regulation. Its activity influences the metabolic options a cell can use. By knowing the metabolic pathways that distinguish active cells from dormant cells, scientists can wake up dormant cells by modifying their mitochondrial metabolism.

Biologists have blocked MPC activity by using chemical inhibitors or by generating mutant mice for the Mpc1gene. Using these pharmacological and genetic approaches, the scientists were able to activate dormant NSCs and thus generate new neurons in the brains of adult and even aged mice.

These results shed new light on the role of cell metabolism in the regulation of neurogenesis. In the long term, these results could lead to potential treatments for conditions such as depression or neurodegenerative diseases.

Francesco Petrelli, Valentina Scandella, Sylvie Montessuit, Nicola Zamboni, Jean-Claude Martinou, Marlen Knobloch. Mitochondrial pyruvate metabolism regulates the activation of quiescent adult neural stem cells. Science Advances, 2023; 9 (9) DOI: 10.1126/sciadv.add5220

'Plasticosis': The First Disease Caused by Ingested Plastic Was Just Described by Scientists

One of the most plastic-contaminated birds in the whole world is silently suffering from a novel, emerging disease scientists have coined 'plasticosis'.

It's reportedly the first time researchers have ever documented and quantified the pathological effects of ingested plastic in wild animals, and it's got scientists stressing about the health of more than just one species.

The new findings suggest sharp plastic fragments can literally tear some seabirds apart from the inside.

This new  study clearly demonstrates the ability of plastic to directly induce severe, organ-wide scar tissue formation or 'plasticosis' in wild, free-living animals, which is likely to be detrimental to individual health and survival, acccording to reporters. 

When it comes to physical damage caused by ingested plastic, flesh-footed shearwaters (Ardenna carneipes) are the canaries in the coal mine.

Despite the sheer distance from human civilization, many of the chicks hatched on Lord Howe are suffering a slow and sickly death that seems to be all our fault.

Each autumn, gaunt and bedraggled fledglings litter the island's beaches, and for years now, scientists have been trying to figure out why so many of these seabirds are sick and dying.

When researchers examined the carcasses of dozens of dead birds from Lord Howe, they found excessive and irreversible signs of scar tissue in stomach after stomach. The extensive internal scarring is most likely caused by tiny bits of sharp plastic digging into a bird's internal lining over and over. Without the chance to heal, the first chamber of the bird's stomach, called the proventriculus, grows distorted with damage.

Sometime back researchers described about a bird stomach so full of plastic it was "bulging… almost rupturing". The scientists conducting the necropsy counted 202 plastic pieces in total.

That's hardly an exceptional circumstance. Roughly 90 percent of necropsied birds on Lord Howe island have contained plastic in their stomachs.

The consistent scarring and chronic inflammation observed in seabird stomachs filled with plastic has scientists thinking this is a specific fibrotic disease.

They've called it 'plasticosis' to keep in line with other fibrotic diseases, like silicosis and asbestosis, which are also marked by tissue damage from pollutants, except in these cases the damage occurs in the lungs.

lab studies have shown that sharp, ingested macroplastics, around 5 millimeters in size, can block, ulcerate, or perforate digestive tracts, while also reducing feeding behavior. In severe cases, the animal can even starve to death.

The study among shearwaters is the first to show plasticosis occurring among wild animals.

Part 1

In the hardened and inflexible stomach of a plastic-filled shearwater, room for new food is limited and digestion seems to be severely impacted. With so much scar tissue, scientists say the lining of the internal organ is not nearly as good at secreting digestive enzymes or absorbing nutrients.

The resulting loss of nourishment could be a key reason why so many shearwaters on Lord Howe are underweight. Since 2010, their average body mass has plummeted. And in the current study, higher numbers of plastic pieces in a shearwater's stomach were associated with a lower overall body weight.

"The tubular glands, which secrete digestive compounds, are perhaps the best example of the impact of plasticosis.

"When plastic is consumed, these glands get gradually more stunted until they eventually lose their tissue structure entirely at the highest levels of exposure."

The consequences of ingesting plastic may not be the same for all seabird stomachs, or even all animal stomachs, but given the ubiquitous nature of ingested plastic in the marine food web, there's reason to worry about the health effects.

In humans, recent studies have shown people with inflammatory bowel disease (IBD) tend to have elevated levels of microplastics in their feces.

Among 52 participants, greater plastic exposure was closely aligned with the worst IBD symptoms.

That study was only small and does not establish cause and effect, but since microplastics have been found in human blood, placenta, feces, and the deepest parts of our lungs, toxicologists say we need urgent health assessments.

Ingested plastic can not only cause physical damage, it can also provide a way for parasites and microbes to hitchhike into the body. In addition, as plastics degrade, they may leech toxic and persistent chemicals with potentially dangerous health effects.

Part 2

Plasticosis may be the first wildlife disease connected to plastics, but it may not be the last.

https://www.sciencedirect.com/science/article/pii/S0304389423003722...

Part 3