The two birds that the researchers discovered to be poisonous are the regent whistler (Pachycephala schlegelii), a species that belongs to a family of birds with a wide distribution and easily recognizable song well-known from across the Indo-Pacific region, and the rufous-naped bellbird (Aleadryas rufinucha).

Most people are familiar with South and Central America's iconic poison dart frogs—especially the golden poison frog. These small, brightly colored amphibians can kill a human at the slightest touch. The discovery of the two new poisonous bird species in New Guinea, which carry the same type of toxin in their skin and feathers, demonstrates that the frog toxin is more widespread than once believed.

The poison in these birds' bodies and plumage is called Batrachotoxin. It is an incredibly potent neurotoxin that, in higher concentrations, such as those found in the skin of golden poison frogs, leads to muscle cramps and cardiac arrest nearly immediately after contact.

The bird's toxin is the same type as that found in frogs, which is a neurotoxin that, by forcing sodium channels in skeletal muscle tissue to remain open, can cause violent convulsions and ultimately death.

Though the level of toxicity of the New Guinean birds is less lethal, it may still serve a defensive purpose, but the adaptive significance for the birds is yet uncertain.

The locals aren't fond of spicy food and steer clear of these birds, because, according to them, their meat burns in the mouth like chili. In fact that's how researchers first became aware of them. And the toxin can be felt when holding onto one of them. It feels kind of unpleasant, and hanging on to one for long isn't an appealing option. This could indicate that the poison serves them as a deterrence of those who would want to eat them to some degree.

According to the researchers, the poisonous birds are an expression of an everlasting evolutionary arms race in nature. It starts at the bottom of the food chain with beetles, insects and other invertebrates. Over time, some of these develop toxicity to avoid being eaten. Perhaps they also acquire a particular coloration that may serve as a warning. This in turn allow them to venture from their hideouts beneath logs and rocks.

Part 2

There is a distinction in biology between the two ways that animals deploy poisons. There are poisonous animals that produce toxins in their bodies and others that absorb toxins from their surroundings. Like the frogs, the birds belong to the latter category. Both are believed to acquire toxins from what they eat. Beetles containing the toxin have been found in the stomachs of some of the birds. But the source of the toxin itself has yet to be determined.

What makes it possible for these birds to have a toxin in their bodies without themselves being harmed? The researchers studied this with inspiration from poison dart frogs, whose genetic mutations prevent the toxin from keeping their sodium channels open, and thereby preventing cramps.

So, it was natural to investigate whether the birds had mutations in the same genes. Interestingly enough, the answer is yes and no. The birds have mutations in the area that regulates sodium channels, and which we expect gives them this ability to tolerate the toxin, but not in the exact same places as the frogs.

Finding these mutations that can reduce the binding affinity of Batrathotoxin in poisonous birds in similar places as in poison dart frogs, is quite cool. And it showed that in order to adapt to this Batrachotoxin lifestyle, you need some sort of adaptation in these sodium channels".

Therefore, these studies of the birds establish that while their neurotoxin is similar to that of the South American poison dart frogs, the birds developed their resistance and ability to carry it in the bodies independently of the frogs. This is an example of what biologists refer to as convergent evolution.

 Kasun H. Bodawatta et al, Multiple mutations in the Nav1.4 sodium channel of New Guinean toxic birds provide autoresistance to deadly batrachotoxin, Molecular Ecology (2023). DOI: 10.1111/mec.16878

Part 3

Scientists observe flattest explosion ever seen in space

An explosion the size of our solar system has baffled scientists, as part of its shape—similar to that of an extremely flat disk—challenges everything we know about explosions in space.

The explosion observed was a bright Fast Blue Optical Transient (FBOT)—an extremely rare class of explosion which is much less common than other explosions, such as supernovas. The first bright FBOT was discovered in 2018 and given the nickname "the cow."

Explosions of stars in the universe are almost always spherical in shape, as the stars themselves are spherical. However, this explosion, which occurred 180 million light years away, is the most aspherical ever seen in space, with a shape like a disk emerging a few days after it was discovered. This section of the explosion may have come from material shed by the star just before it exploded.

It's still unclear how bright FBOT explosions occur, but it's hoped that this observation, published in Monthly Notices of the Royal Astronomical Society, will bring us closer to understanding them.

Justyn R Maund et al, A flash of polarized optical light points to an aspherical 'cow', Monthly Notices of the Royal Astronomical Society (2023). DOI: 10.1093/mnras/stad539

Ban On Tattoo Ink: Breaking Down the Chemistry

Microplastic found in Antarctic krill and salps

A new study by researchers discovered microplastics in krill (Euphausia superba), a small shrimp-like crustacean, and salps (Salpa thompsoni), a gelatinous marine invertebrate. The results were published in the journal Royal Society Open Science.

While Antarctic krill have been observed ingesting microplastics in laboratory settings, the team's findings provide important evidence that these animals, as well as other zooplankton, ingest plastic in their natural environment.

Microplastics are present in the Southern Ocean from the sea surface to seabed. Due to the small size of these particles (<5 mm), Antarctic zooplankton are likely to mistake the plastics for their natural food source. The team focused on two of the most abundant species of Southern Ocean zooplankton: Antarctic krill, and salps. These two species are critical to the diet of much of the Southern Ocean's marine wildlife. Krill is the main food source for whales, penguins, and seals while salps are eaten by some fish and larger marine birds.

Krill and salp samples were collected onboard the research ship RRS James Clark Ross on two research missions off the Northern tip of the Antarctic Peninsula in 2016 and near the island of South Georgia in 2018. Microplastics were extracted from both species with plastic microfibers most common. One of the largest sources of these fibers is shedding from clothing during washing and drying. Around 60% of the krill and salps contained nylon, a microplastic with significant commercial applications in clothing, fishing gear, ropes, and reinforcing car tires.

The findings underline how sensitive the Antarctic marine ecosystem is to plastic pollution. Due to the short food chains in the Antarctic, transfer of these microplastics from the krill to larger predators such as whales, penguins, and seals is highly likely. Plastic in krill and salps could also negatively impact the Southern Ocean as one of the planets largest carbon sinks.

Scientists have found microplastic pollution in krill and salps from the Southern Ocean. A new study led by researchers at British Antarctic Survey shares important evidence that these animals, as well as other zooplankton, ingest plastic in their natural environment. Krill and salps are vital food sources to much of the Southern Ocean’s wildlife as well as helping to trap carbon from the atmosphere in the deep ocean. The impact of the microplastics in this environment is not fully understood and could interfere with their ability to trap carbon as well as getting transferred up the food chain to animals such as whales and penguins. The team found plastics in most krill and salp samples with the most common type being nylon, a fibre with wider ranging applications from clothing to car tires. ➡ Read this news story on the British Antarctic Survey website: https://www.bas.ac.uk/media-post/micr...

Part 2

Gigapixel 3D Microscope Captures Life in Unprecedented Detail

A new kind of microscope that stitches together videos from dozens of smaller cameras can provide researchers with 3D views of their experiments. Whether recording 3D movies of the behavior of dozens of freely swimming zebrafish or the grooming activity of fruit flies at near cellular-level detail across a very wide field of view, the device is opening new possibilities to researchers the world over. Learn more at https://www.pratt.duke.edu/about/news...

Neck cracking

It is thought that one of the most common causes of neck ‘cracking’ is gas bubbles in the synovial fluid escaping a tight space. This synovial fluid

is a lubricant between the joints, formed by a combination of carbon dioxide, nitrogen and oxygen.

If you deliberately roll your neck, it is thought that you can sometimes release these bubbles, resulting in a series of popping sounds that may sound like cracking. The release of the gas build-up explains why muscles or joints often feel looser and more comfortable after they’ve been ‘popped’ or ‘cracked’.

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Our joints contain synovial fluid, a sac of liquid which acts as a lubricant, protecting bones from grinding against each other. When someone cracks their knuckles, they increase the space in the joint, causing bubbles of gas (think oxygen, nitrogen and carbon dioxide) to form in the fluid. It’s the popping of these bubbles that make the cracking noise.

While it may sound worrying, there isn’t actually much evidence to suggest this is dangerous – or increases the risk of getting arthritis. The most important risk factors for developing arthritis are family history, age, gender, joint injury, and lifestyle elements such as smoking and obesity.

It is true that people with arthritis sometimes find their joints crack, but this is because their cartilage has already been damaged. Cracking isn’t usually the most common symptom of arthritis, either.

Although there are isolated reports of self-injury caused from cracking knuckles, such as sprained ligaments, these are very rare. You’re much more likely to harm yourself by cracking joints in your spine and neck, which are surrounded by important blood vessels.

Crystallised intelligence (the ability to accumulate knowledge, facts and skills) 

Fluid intelligence (the ability to reason and think flexibly)

Photosynthetic Sea Slugs 

Obesity treatment could offer dramatic weight loss without surgery ...

Imagine getting the benefits of gastric bypass surgery without going under the knife—a new class of compounds could do just that. In lab animals, these potential treatments reduce weight dramatically and lower blood glucose. The injectable compounds also avoid the side effects of nausea and vomiting that are common with current weight-loss and diabetes drugs. Now, scientists report that the new treatment not only reduces eating but also boosts calorie burn.

ACS Spring 2023: Peptide triagonists of the GLP-1-, neuropeptide Y1- and neuropeptide Y2- receptors for glycemic control and weight loss, www.acs.org/meetings/acs-meetings/spring-2023.html

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Time-restricted eating vs. daily calorie restriction in reducing no...

Adults with obesity and nonalcoholic fatty liver disease did not see additional reductions in intrahepatic triglyceride while on a time-restricted eating regimen compared to subjects on a daily calorie-restriction diet. This is according to a recent study published in the journal JAMA Network Open and led by researchers at Southern Medical University in Guangzhou, China and colleagues in the US at Tulane University School of Public Health and Tropical Medicine in New Orleans.

Xueyun Wei et al, Effects of Time-Restricted Eating on Nonalcoholic Fatty Liver Disease, JAMA Network Open (2023). DOI: 10.1001/jamanetworkopen.2023.3513

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Study finds harmful PFAS don't actually prevent furniture stains

The health and environmental harms of per- and polyfluoroalkyl substances (PFAS) are well-known, but a new study calls into question their touted stain-fighting benefits. The study, published today in the AATCC Journal of Research, tested the performance of PFAS finishings on furniture fabrics and found that they had limited to no effectiveness, particularly under real-world conditions.

From yeast to mice, from mice to man: Senescent cells get noisier with age

Getting old seems completely avoidable in youth but becomes less and less so as we age. Many of the obstacles of advanced aging are well understood, including declining eyesight, hearing loss, back, neck and arthritic joint pains, shortness of breath, diabetes, Alzheimer's disease, dementia, cancer and stroke, just to name a few. What is less understood are the cellular-level molecular mechanisms responsible for our overall decline.

So researchers pursued an investigation into the chromatin-mediated loss of transcriptional fidelity during human cellular senescence. Their findings are described in an article titled "Spurious intragenic transcription is a feature of mammalian cellular senescence and tissue aging," published in the journal Nature Aging. 

Senescence is the step cells take when they determine it is best not to replicate, inhibiting the proliferation of abnormal cells by altering chromosomal configurations. Essentially as we age, our dividing cells accumulate mutations, little changes from one generation of cells to the next. Enough of these and the cell is at risk of being unsustainable or becoming a tumor cell. In this sense, senescence plays an essential role in limiting tumor progression.

Senescence is also a response to damage, allowing for the suppression of damaged or poorly repaired cells or damage of the telomeres. Accelerated accumulation of senescent cells with age is associated with various forms of disease—osteoarthritis, lung disease, Alzheimer's, dementia and cancer, to name a few.

Scientists found that during aging and senescence, cryptic transcription (proteins not normally produced) are suddenly created inside cells and that this is related to changes in the chromatin landscape. The study proposes that cryptic transcription is spurious and not created for a specific purpose. The noisy cryptic transcriptome then competes indirectly with coherent transcriptional networks by expending cells' energy on their production. Researchers saw no evidence of cryptic transcription being sensed as damage by the cell, nor do they think it is causative of senescence but simply a result of changes brought on by senescence.

The study, along with an experiment in mouse livers, builds on previous observations of cryptic transcription and indicates that this senescence  mechanism is conserved from yeast to mice and humans. The study also finds, similar to previous reports, that cryptic transcription tissue location is sex-dependent, as males and females will manifest spurious proteins in different cell types.

Payel Sen, Spurious intragenic transcription is a feature of mammalian cellular senescence and tissue aging, Nature Aging (2023). DOI: 10.1038/s43587-023-00384-3. www.nature.com/articles/s43587-023-00384-3

Isima, N., Gil, J. Spurious transcription may be a hallmark of aging. Nature Aging (2023). DOI: 10.1038/s43587-023-00398-x. www.nature.com/articles/s43587-023-00398-x

Serotonin gates the transfer of visual information from the eyes to the thalamus

Humans are known to perceive the environment around them differently based on the situation they are in and their own feelings and sensations. Internal states, such as fear, arousal or hunger can thus affect the ways in which sensory information is processed and registered by the brain.

Researchers have recently carried out a study investigating the possible effects of serotonin, a neurotransmitter known to regulate sleep, mood, sexual desire, and other inner states, in the processing of visual information. Their findings, published in Neuron, suggest that serotonergic neurons in the brainstem (i.e., the central trunk of the mammalian brain) gate the transfer of visual information from the eyes to the thalamus, an egg-shaped area of the brain.

Internal states are known to affect sensory perception and processing, but this was generally thought to occur in the cortex or thalamus. 

Previous studies revealed that arousal can suppress certain visual information channels at an earlier stage of the visual pathway––at the connection between the mouse retina and the thalamus, before the information even reaches the brain. This form of 'filtering' of information suggests a very efficient means of processing only relevant information. 

Past studies have also found that internal states, including arousal, are mediated by neuromodulatory systems in the brainstem and other areas below the cortex, including the serotonergic system. This is essentially the system responsible for regulating physiological states through the transmission of serotonin.

Researchers specifically explored now the effects of serotonin on the early processing of visual information and its transfer from the eyes to the thalamus. To do this, they used a technique known as two-photon calcium imaging to track the activity of individual retinal axons in the brains of awake mice as they viewed visual images on a computer monitor.

While examining the mice, the researchers also increased the release of serotonin in the thalamus, by optogenetically stimulating serotonergic neurons as they entered the thalamus. Optogenetic stimulation is a research technique used to intensify the activity of a set of genetically defined neurons using light.

Part 1

The experiments carried out by this team of researchers yielded very interesting results. Notably, they showed that serotonin can suppress calcium signals in retinal axons and the release of glutamate in the thalamus. This ultimately reduces the transmission of visual signals from the eye to the thalamus.

When they analyzed their results more in detail, the researchers  found that some classes of retinal axons tended to be more suppressed by serotonin, with classes that responded to broad changes in light levels being more affected than those responding to fine visual details.

The researchers also compared the selective modulation observed in their experiments to that naturally occurring when animals or humans are highly aroused. They found that periods of high arousals that were not accompanied by an increase in the release of serotonin tended to suppress the retinal axons transmitting information about fine details, rather than changes in light levels.

Overall, the results of this study confirm that different internal states can impact the processing of separate types of visual information. 

Jasmine D.S. Reggiani et al, Brainstem serotonin neurons selectively gate retinal information flow to thalamus, Neuron (2022). DOI: 10.1016/j.neuron.2022.12.006

Part 2

New shape-shifting antibiotics could fight deadly infections

Antibiotics are essential and effective, but in recent years overuse has led to some bacteria developing resistance to them. The infections are so difficult to treat, the World Health Organization deemed antibiotic resistance a top 10 global public health threat.

Researchers have now  created a new weapon against these drug-resistant superbugs—an antibiotic that can shape-shift by rearranging its atoms.

They came up with the idea of shape-shifting antibiotics while observing tanks in military training exercises. With rotating turrets and nimble movements, the tanks could respond quickly to possible threats.

A few years later, the researchers learned of a molecule called bullvalene. Bullvalene is a fluxional molecule, meaning its atoms can swap positions. This gives it a changing shape with over a million possible configurations—exactly the fluidity they were  looking for.

Several bacteria, including MRSA, VRSA, and VRE, have developed resistance to a potent antibiotic called vancomycin, used to treat everything from skin infections to meningitis. Moses thought he could improve the drug's bacteria-fighting performance by combining it with bullvalene.

Then they turned to click chemistry, a Nobel Prize–winning class of fast, high-yielding chemical reactions that "click" molecules together reliably. This makes the reactions more efficient for wide-scale use.

Using this technique, teh researchers created a new antibiotic with two vancomycin "warheads" and a fluctuating bullvalene center.

They tested the new drug in collaboration with Dr. Tatiana Soares da-Costa (University of Adelaide). The researchers gave the drug to VRE-infected wax moth larvae, which are commonly used to test antibiotics. They found the shape-shifting antibiotic significantly more effective than vancomycin at clearing the deadly infection. Additionally, the bacteria didn't develop resistance to the new antibiotic.

Researchers can use click chemistry with shape-shifting antibiotics to create a multitude of new drugs to use against various microbes.

Alessandra Ottonello et al, Shapeshifting bullvalene-linked vancomycin dimers as effective antibiotics against multidrug-resistant gram-positive bacteria, Proceedings of the National Academy of Sciences (2023). DOI: 10.1073/pnas.2208737120

When you’re having a cast removed, why doesn’t the machine cut your limb?

An orthopaedic cast is usually removed with a special cast saw, which is an oscillating power tool. While it might look like it could cause a lot of damage, a cast saw is designed with a sharp, small-toothed blade that rapidly oscillates back and forth over a very small angle to cut material.

This is quite different to a normal circular saw, which has a rotating blade. A cast saw needs resistance to cut, and is specially designed to slice through rigid materials such as plaster. If it comes into contact with soft tissues such as skin, there is less resistance and so the saw will not cause injury.

The unexpected contribution of medieval monks to volcanology

By observing the night sky, medieval monks unwittingly recorded some of history's largest volcanic eruptions. An international team of researchers drew on readings of 12th and 13th century European and Middle Eastern chronicles, along with ice core and tree ring data, to accurately date some of the biggest volcanic eruptions the world has ever seen.

Their results, reported in the journal Nature, uncover new information about one of the most volcanically active periods in Earth's history, which some think helped to trigger the Little Ice Age, a long interval of cooling that saw the advance of European glaciers.

It took the researchers almost five years to examine hundreds of annals and chronicles from across Europe and the Middle East, in search of references to total lunar eclipses and their coloration. Total lunar eclipses occur when the moon passes into the Earth's shadow. Typically, the moon remains visible as a reddish orb because it is still bathed in sunlight bent round the Earth by its atmosphere. But after a very large volcanic eruption, there can be so much dust in the stratosphere—the middle part of the atmosphere starting roughly where commercial aircraft fly—that the eclipsed moon almost disappears.

Medieval chroniclers recorded and described all kinds of historical events, including the deeds of kings and popes, important battles, and natural disasters and famines. Just as noteworthy were the celestial phenomena that might foretell such calamities. Mindful of the Book of Revelation, a vision of the end times that speaks of a blood-red moon, the monks were especially careful to take note of the moon's coloration. Of the 64 total lunar eclipses that occurred in Europe between 1100 and 1300, the chroniclers had faithfully documented 51. In five of these cases, they also reported that the moon was exceptionally dark.

Part 1

The researchers realized that the darkest lunar eclipses all occurred within a year or so of major volcanic eruptions. Since they know the exact days of the eclipses, it opened the possibility of using the sightings to narrow down when the eruptions must have happened.

The researchers found that scribes in Japan took equal note of lunar eclipses. One of the best known, Fujiwara no Teika, wrote of an unprecedented dark eclipse observed on 2 December 1229: "The old folk had never seen it like this time, with the location of the disk of the Moon not visible, just as if it had disappeared during the eclipse... It was truly something to fear." The stratospheric dust from large volcanic eruptions was not only responsible for the vanishing moon. It also cooled summer temperatures by limiting the sunlight reaching the Earth's surface. This in turn could bring ruin to agricultural crops.

Strong tropical eruptions can induce global cooling on the order of roughly 1°C over a few years. They can also lead to rainfall anomalies with droughts in one place and floods in another.

Despite these effects, people at the time could not have imagined that the poor harvests or the unusual lunar eclipses had anything to do with volcanoes—the eruptions themselves were all but one undocumented. Scientists only knew about these eruptions because they left traces in the ice of Antarctica and Greenland. By putting together the information from ice cores and the descriptions from medieval texts they can now make better estimates of when and where some of the biggest eruptions of this period occurred.

The collective effect of the medieval eruptions on Earth's climate may have led to the Little Ice Age, when winter ice fairs were held on the frozen rivers of Europe.

Sébastien Guillet, Lunar eclipses illuminate timing and climate impact of medieval volcanism, Nature (2023). DOI: 10.1038/s41586-023-05751-z. www.nature.com/articles/s41586-023-05751-z

Part 2

Previously unknown isotope of uranium discovered

A team of nuclear physicists affiliated with multiple institutions in Japan, working with a colleague from Korea, has discovered a previously unknown uranium isotope with atomic number 92 and mass 241. In their study, reported in the journal Physical Review Letters, the group forced the isotope to reveal itself and tested the results of their efforts to show that what they had found was indeed uranium-241.

T. Niwase et al, Discovery of New Isotope U241 and Systematic High-Precision Atomic Mass Measurements of Neutron-Rich Pa-Pu Nuclei Produced via Multinucleon Transfer Reactions, Physical Review Letters (2023). DOI: 10.1103/PhysRevLett.130.132502

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Study shows soil pollution in urban green spaces and natural areas ...

An international study shows that soil in urban green spaces and natural areas share similar levels of multiple contaminants such as metals, pesticides, microplastics and antibiotic resistance genes around the world. Soil contamination is one of the main threats to the health and sustainability of ecosystems.

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Scientists invent spray cooling to lower carbon footprint of data c...

Scientists from Nanyang Technological University, Singapore (NTU Singapore) have invented a more sustainable and green method for cooling down servers in data centers, potentially reducing up to 26% in both energy costs and carbon footprint.

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Euchromatin is not really open in living cells, shows study

DNA and associated proteins in active regions of the genome are condensed but behave like a viscous liquid at the molecular level. This finding greatly increases our understanding of the physical nature of expressed genome 

How were amino acids, one of the key building blocks of life, formed before the origin of life on Earth?

Our solar system formed from a molecular cloud, which was composed of gas and dust that was emitted into the interstellar medium (ISM), a vast space between stars. On collapse of the molecular cloud, the early sun was formed, with a large disk of gas and dust orbiting it. The dusty material collided to produce rocky material that would eventually grow in size to become large bodies called planetesimals.

The planetesimals that formed far enough from the sun, also contained large quantities of ice. The ice consisted of water and other volatile compounds, such as carbon monoxide (CO), carbon dioxide (CO2), methanol (CH3OH) and ammonia (NH3), as well as many other organic compounds, likely including some amino acids. Eventually, the ice melted due to the presence of radioactive material that heated up the bodies. This period of liquid water (termed aqueous alteration) enabled many reactions to occur, including Strecker synthesis and Formose-like reactions, the result being the production of new organic material, including amino acids.

The same process also changed the rocky materials from their original minerals to new secondary minerals, such as phyllosilicates, carbonates, Fe-oxides and Fe-sulfides.

After several millions of years, the planetesimals began to freeze, as the radioactive material was used up. Later catastrophic collisions and interaction with the solar systems planets broke up the large bodies and sent their asteroidal and cometary fragments close to Earth.

Further impact events have since delivered fragments of these asteroids and comets to the Earth's surface, supplying the Earth with large quantities of organic material, including amino acids, over the course of its history.

Part 1

Amino acids are within all living things on Earth, being the building blocks of proteins. Proteins are essential for many processes within living organisms, including catalyzing reactions (enzymes), replicating genetic material (ribosomes), transporting molecules (transport proteins) and providing a structure to cells and organisms (e.g. collagen).

Therefore, amino acids would have been needed in significant amounts within the region where life began on Earth.

Previous work has identified a number of possible settings both on the Early Earth and in extraterrestrial environments that can form amino acids. Interestingly, most amino acids come in at least two forms, whose structures represent mirror images of each other, similar to human hands. Accordingly, these are often referred to as the right-handed or left-handed optical isomers. One interesting characteristic of life on Earth is that it uses one particular type of amino acids in its proteins, the left-handed optical isomer.

Currently, only a certain class of meteorites (carbonaceous chondrites) are known to contain excesses of left-handed optical isomers, which has led to the idea that the amino acids used by life may have originated from these meteorites. Despite this, the amino acids in meteorites could have formed before their incorporation into the meteorites or after the meteorites had already formed.

In a study now published in Nature Communications, a team of scientists analyzed several fragments of the asteroid Ryugu and calculated the abundance of amino acids within them. The abundance of the mineral phases within the particles had been previously reported in another publication, which allowed for a comparison between the abundance of amino acids and minerals. It was found that one particle (A0022) contained a high abundance of an amino  acid that is uncommon in extraterrestrial materials, called dimethylglycine (DMG), whereas the other particle (C0008) did not contain this amino acid above detection limit.

Part 2

Meanwhile, the abundance of the amino acid glycine was found to be lower in A0022 compared to C0008, while the abundance of β-Alanine showed the opposite trend. Accordingly, the ratio of β-Alanine to glycine was higher for A0022 than for C0008. This ratio was shown previously to be indicative of the extent of aqueous alteration operating on planetesimals. Accordingly, it was hypothesized that some reaction related to higher levels of aqueous alteration in A0022 may explain the high abundance of DMG in this particle, compared to C0008.

As such, the mineral phases were examined to see if any additional evidence for what reaction may be causing the different amino acids abundances between the Ryugu particles. It was found that the abundance of secondary minerals (formed after aqueous alteration), including carbonate, magnetite and Fe-sulfides, was higher in A0022 than in C0008.

In particular, the high abundance of carbonate pointed towards a larger quantity of CO or CO₂ within the region of the planetesimal where A0022 had been altered, compared to C0008. In conjunction with the evidence for more intense aqueous alteration from the β-Alanine to glycine ratio, this indicated that more ice in general may have been present in the precursor of A0022 than in C0008.

One way to commercially produce DMG, an important nutrient for humans, is the through the Eschweiler–Clarke reaction. This reaction requires the interaction of glycine with formic acid and formaldehyde in water and also produces CO₂. Glycine, formaldehyde and formic acid are all found in comets and so it is expected that they would be present in the planetesimal precursors of asteroids.

Therefore, if the Eschweiler–Clarke reaction occurred during aqueous alteration within the precursor of A0022, then it could explain the high level of DMG and lower abundance of glycine in this particle, compared to C0008. Additionally, the CO₂ produced could have further contributed to the formation of carbonates in A0022.

Overall, the findings of the study indicate that slight differences in the conditions present during aqueous alteration on planetesimals can have big effects on the end abundances of amino acids. Some amino acids can be destroyed and others created and this in turn will affect the availability of amino acids at the origin of life on Earth.

Christian Potiszil et al, Insights into the formation and evolution of extraterrestrial amino acids from the asteroid Ryugu, Nature Communications (2023). DOI: 10.1038/s41467-023-37107-6

Part 3

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Study finds evidence of no common blood microbes in healthy humans

There is no stable microbial community residing in the bloodstream of healthy humans, according to a new study.

The new Nature Microbiology paper makes an important confirmation as blood donations are a crucial part of medical practice. Understanding what types of microbes may be found in blood may allow the development of better microbial tests in blood donations, which would minimize the risk of transfusion-related infections.

Human blood is generally considered sterile. While sometimes microorganisms will enter the bloodstream such as via a wound or after tooth-brushing, mostly this is quickly resolved by the immune system.

But in recent decades this paradigm has been challenged by speculation that the blood could host a community of microbes. This new study has confirmed this is not the case, as most people's blood does not contain microbes, and the microbial species found in some people's blood varied substantially between individuals.

In these investigations, after accounting for contamination that is rife in microbiome investigations, the team found that microbes were only rarely and sporadically detected in blood, instead of existing as stable communities. Among their sample of 9,770 people, 84% of people did not have any microbes in their blood sample, and less than 5% of people shared the same species.

The scientists also found evidence that some bacteria in the blood of healthy individuals might be replicating and most of these bacteria are typically found in the human gut, oral, or skin microbiomes. Their findings suggest that microbes do occasionally enter the bloodstream from other body sites without causing disease, but there is no core set of species colonizing the blood of healthy individuals.

The findings also provide a useful resource for the types of microbes that one might expect to occasionally see in the blood of healthy humans. Characterizing the range of microbial species present in the blood of healthy individuals forms a crucial baseline for comparison with that of diseased individuals, shedding light on how blood microbial profiles may correlate with health status.

Cedric C. S. Tan et al, No evidence for a common blood microbiome based on a population study of 9,770 healthy humans, Nature Microbiology (2023). DOI: 10.1038/s41564-023-01350-w

No microbial community in the blood of healthy individuals, Nature Microbiology (2023). DOI: 10.1038/s41564-023-01364-4

Scientists Find Antibiotic-Free Way to Treat Drug-Resistant Infections

Scientists have found an antibiotic-free way of treating 'golden staph' skin infections that are the scourge of some cancer patients, and a threat to hospital-goers everywhere.

The lab study from researchers  utilized an artificial version of an enzyme that's naturally produced by bacteriophages (viruses that infect bacteria), and used it to eradicate Staphylococcus aureus, or golden staph, in biopsy samples from people with skin lymphoma.

To people who are severely ill with skin lymphoma, staphylococci can be a huge, sometimes insoluble problem, as many are infected with a type of Staphylococcus aureus that is resistant to antibiotics. 

S. aureus is a common inhabitant of our skin and nasal tract, and generally harmless. But it is an opportunistic pathogen: When immunity is lowered, it can cause all manner of infections, from minor skin infections such as boils and abscesses, right through to life-threatening illnesses such as pneumonia and sepsis.

In a hospital setting, drug-resistant strains of the bacteria are a grave and growing problem. S. aureus can find its way into the bloodstream during surgery or via medical devices such as catheters, slipping past the body's first line of defense: the skin and mucosal barriers (snot).

People with weakened immune systems who visit hospitals for regular treatments such as chemotherapy are also at risk of picking up nasty 'superbugs' that have become resistant to mainstay antibiotics.

In particular, people with skin lymphoma are highly susceptible to bacterial infections. Called cutaneous T-cell lymphoma, CTCL is a rare form of non-Hodgkin lymphoma that starts with cancerous T cells migrating to the skin. There, these rogue immune cells cause rashes and lesions before spreading to other parts of the body.

S. aureus expels substances called enterotoxins which are thought to fuel the progression of CTCL, because when patients with CTCL finish a round of antibiotics, S. aureus can quickly appear in skin lesions and their cancer symptoms can worsen.

Part 1

Strains of S. aureus that are resistant to methicillin and other antibiotics are called MRSA, and while hospitals are making some ground in curbing MRSA infections, other drug-resistant superbugs are quick to take its place.

So, in this study, researchers experimented with the new class of antibacterial agent called endolysins.

Endolysins are enzymes that are naturally produced by bacteriophages, viruses that infect bacteria. After infection, they slice up molecules called peptidoglycans that form mesh-like scaffolds in the bacteria cell wall, destroying the bacteria from the inside.

Each bacterial species has unique peptidoglycans, which the right endolysin could selectively target. One endolysin, XZ.700, was tested in this study, on skin samples collected from people with healthy skin, and those with CTCL.

The great thing about this enzyme is that it has been designed to penetrate the wall of Staphylococcus aureus. This enables it to target and kill the harmful staphylococcus and leave harmless skin bacteria unharmed.

In lab experiments, endolysin XZ.700 killed off strains of S. aureus that had been isolated from CTCL patients, and blocked its tumor-promoting effects on lab-grown malignant T cells.

Endolysin treatment also "profoundly" stopped S. aureus from colonizing samples of healthy skin and biopsies of lesioned skin from people with CTCL. It also sloughed off S. aureus colonies that had already settled on biopsied skin.

 Lab tests have showed that endolysins do not just eradicate Staphylococcus aureus" from skin samples,  but that they "also inhibit their ability to promote cancer growth."

https://www.jidonline.org/article/S0022-202X(23)00175-6/fulltext

Using photons as neurotransmitters to control the activity of neurons

Our brains are made of billions of neurons, which are connected forming complex networks. They communicate between themselves by sending electrical signals, known as action potentials, and chemical signals, known as neurotransmitters, in a process called synaptic transmission.

Chemical neurotransmitters are released from one neuron, diffuse to the others and arrive at the targeted cells, generating a signal which excites, inhibits or modulates the cellular activity. The timing and strength of these signals are crucial for the brain to process and interpret sensory information, make decisions, and generate behaviour.

Controlling the connections between the neurons would allow us to understand and treat better neurological disorders, rewire or repair the malfunctions of the neural circuits after being damaged, improve our learning capabilities or expand our set of behaviours.

There are several approaches to controlling neuronal activity. One possible method is using drugs, that alter the levels of the chemical neurotransmitters in the brain and affect the activity of neurons. Another approach is to use electrical stimulation applied to specific brain regions to activate or inhibit the neurons. A third possibility is using light to control neural activity.

Using light to manipulate neuronal activity is a relatively new technique that has been explored in the past. It involves genetically modifying neurons to express light-sensitive proteins, ion channels, pumps or specific enzymes in the target cells. This technique allows researchers to precisely control the activity of concrete populations of neurons with higher precision.

However, light needs to be delivered very close to the neurons to achieve enough resolution at the level of the synapsis, as light scatters in the brain tissue. Thus, it is often invasive, requiring external interventions. 

To overcome these challenges, a team of ICFO researchers presents in Nature Methods a system that uses photons instead of chemical neurotransmitters as a strategy to control neuronal activity.

Part 1

Light as a messenger offers a broad scope for future potential applications. As photons can be used in other types of cells and several animal species, it has wide-ranging implications for both basic research and clinical applications in neuroscience.

Using light to control and monitor neuronal activity can help researchers better understand the underlying mechanisms of brain function and complex behaviors, and how different brain regions communicate with each other, providing new ways of imaging and mapping brain activity with higher spatial and temporal resolution. It could also help researchers develop new treatments, and for example, be useful for repairing damaged brain connections without invasive surgeries.

However, there are still some limitations to the widespread use of the technology, and further improvements in the engineering of the bioluminescent enzymes and the ion channels or in the targeting of molecules would allow controlling optically the neuronal function, non-invasively and with higher specificity and precision.

Michael Krieg, Neural engineering with photons as synaptic transmitters, Nature Methods (2023). DOI: 10.1038/s41592-023-01836-9. www.nature.com/articles/s41592-023-01836-9

Part 2

Not all itches are the same

Itch is a protective signal that animals use to prevent parasites from introducing potentially hazardous pathogens into the body. If a mosquito lands on a person's arm, they sense its presence on their skin and quickly scratch the spot to remove it. Itchiness due to something like a crawling insect is known as "mechanical" and is distinct from "chemical" itchiness generated by an irritant such as the mosquito's saliva if it were to bite the person's arm. While both scenarios cause the same response (scratching), recent research by  scientists has revealed that, in mice, a dedicated brain pathway drives the mechanical sensation and is distinct from the neural pathway that encodes the chemical sensation.

Their findings, published in Neuron on April 5, 2023, show that a small population of neurons relay mechanical itch information from the spinal cord to the brain and identify the neuropeptide signals that regulate both itch types.

"This study provides fundamental insights into how these two forms of itch are encoded by the brain and opens up new avenues for therapeutic interventions for patients that suffer from a range of chronic itch conditions, including ectopic dermatitis and psoriasis.

Researchers used genetic approaches combined with wearable miniaturized microscopes that allowed the researchers to see itch-induced activity in single neurons of mice. The scientists discovered that by removing an inhibitory pathway involved in itch, they could activate a mechanical itch. By observing subsequent activity and changes occurring in the brainstem, they saw that different cells were responding to either mechanical or chemical itch. This allowed them to classify distinctions between a chemical itch pathway and a mechanical itch pathway and clearly identify the molecules important for regulating them.

They found that if you sensitize one pathway, you can stimulate a pathological itch state, and vice versa. This indicates that these two pathways act together to drive chronic itch.

Next, the scientists plan to examine where in the brain these pathways converge, and then explore the parts of the brain that receive signals that determine the decision of whether to scratch an itch. They also want to better understand how the spinal cord and brainstem differentiate between pain and itch.

These findings should help leverage the development of new therapies for treating the itch.

 Xiangyu Ren et al, Identification of an essential spinoparabrachial pathway for mechanical itch, Neuron (2023). DOI: 10.1016/j.neuron.2023.03.013

Why chewing gum is harmful for the planet?

Globally, people chew roughly 100,000 tonnes of gum each year, but what happens once we’ve finished with it? Ancient civilisations chewed tree resins such as chicle, but by the 1950s this had been replaced by synthetic gums.

Alongside this gum base, modern chewing gum contains softeners such as vegetable oil, emulsifiers that reduce stickiness, fillers like talc to add bulk, plus flavourings, sweeteners, preservatives and colourings. Synthetic gums are generally not biodegradable, but in some cases, they can be recycled into new plastic products.

New, more sustainable chewing gum us alternative natural gums like tree sap or rubber.

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The future is bright for gold-based antibiotics

New research being presented at this year's European Congress of Clinical Microbiology & Infectious Diseases (ECCMID) in Copenhagen, Denmark, (April 15-18) has identified several gold-based compounds with the potential to treat multidrug-resistant "superbugs."

Yellow crazy ant males have two sets of DNA

A small international team of molecular and evolutionary scientists has discovered that male yellow crazy ants (also known as long-legged ants) have two sets of DNA throughout their bodies. In their paper published in the journal Science, the group describes the unique find and discusses possible reasons for it. 

Other scientists suggest in the same journal  that the unique genetic feature of the ants may explain why they are such a successful invasive species.

Prior research has shown that yellow crazy ants, which are native to Asia and West Africa, have the ability to adapt well to new environments, making them a successful invasive species.

Now it turns out that they may have an advantage that has not been seen before: Males have dual sets of DNA.

One of the most basic concepts of biological science is that multicellular organisms develop from a single-cell zygote into a creature with a unique genome. The only exceptions to this rule have been chimeras, which are generally considered accidents of nature. In this new effort, the research team found another exception—male yellow crazy ants with dual sets of DNA.

Prior research had shown anomalies in crazy yellow ant genetics, but until now, it was not clear what was behind apparent discrepancies between queens, males and worker ants. To clear up the mystery, the researchers conducted population genetic and phylogeographic studies of specimens collected from sites across Asia.

They discovered that male yellow crazy ants have two separate genetic lineages—no fusion between maternal and paternal nuclei occurs; thus, both remain active in all males of the species. The research team points out that their findings represent the first-ever discovery of obligate chimerism. They suggest that such chimerism may result from a conflict between competing genetic lineages. And Scientists  suggest that this unique genetic feature may help to prevent inbreeding, which could in turn help the ants survive in unfamiliar territory, explaining their success as an invasive species.

H. Darras et al, Obligate chimerism in male yellow crazy ants, Science (2023). DOI: 10.1126/science.adf0419

Daniel J. C. Kronauer, The unusual genetics of invasive ants, Science (2023). DOI: 10.1126/science.adh1664

Study identifies two different regulatory T cell populations

A regulatory class of human T cells descends from two different origins, one that relates to autoimmunity and one that relates to protective immunity, according to a new study.

When it comes to autoimmunity, the present thinking has been that the only way to stop inflammation is to suppress the immune system broadly, making patients more susceptible to infection.

In teh present study, the researchers identified these two subpopulations of Tfr cells, they analyzed whether these two regulatory T cells express the surface protein CD38 differently. They found that iTfr cells express CD38, whereas nTfr cells do not. They were also able to catalog the precise location of these different subpopulations within the GCs, in addition to demonstrating their developmental path and ability so support B cell function.

"This study raises the question of whether we could selectively deplete iTfr cells through anti-CD38 treatments, while leaving nTfrs intact—using a silver bullet rather than a bomb to target specific T cells. A similar approach could also potentially be used in a therapeutic context to boost immunity in patients with weakened immune systems."

Carole Le Coz et al, Human T follicular helper clones seed the germinal center-resident regulatory pool, Science Immunology (2023). DOI: 10.1126/sciimmunol.ade8162. www.science.org/doi/10.1126/sciimmunol.ade8162

**

Geologists find evidence of dual mass extinctions 260 million years ago

Long before dinosaurs, Earth was dominated by animals that were in many ways even more incredible.

Carnivores such as Titanophoneus, or "titanic murderer," stalked enormous armored reptiles the size of buffalo.

Many of these animals died out in a mass extinction during the Capitanian Age approximately 260 million years ago.

Now an international team of researchers says evidence suggests this mass extinction was not a single event but two, separated by nearly 3 million years. Both were caused by the same culprit: massive volcanic eruptions.

By studying uranium isotope profiles of marine samples collected in the South China Sea, scientists identified two "pulses" in which the oceans became deprived of life-giving oxygen.

In a study published in the journal Earth and Planetary Science Letters, researchers say their analysis provides evidence that the oxygen-deprived oceans precipitated two mass extinctions around 259 million and 262 million years ago during the Middle Permian Period.

By studying these ancient extinctions, researchers can better predict how modern-day global warming could affect the ocean's food chain.

 Huyue Song et al, Global oceanic anoxia linked with the Capitanian (Middle Permian) marine mass extinction, Earth and Planetary Science Letters (2023). DOI: 10.1016/j.epsl.2023.118128

Scientists discover a way Earth's atmosphere cleans itself

Human activities emit many kinds of pollutants into the air, and without a molecule called hydroxide (OH), many of these pollutants would keep aggregating in the atmosphere.

How OH itself forms in the atmosphere was viewed as a complete story, but in new research published in Proceedings of the National Academy of Sciences, a research team  reports that a strong electric field that exists at the surface between airborne water droplets and the surrounding air can create OH by a previously unknown mechanism.

It's a finding that stands to reshape how scientists understand how the air clears itself of things like human-emitted pollutants and greenhouse gasses which OH can react with and eliminate. You need OH to oxidize hydrocarbons, otherwise they would build up in the atmosphere indefinitely.

OH is a key player in the story of atmospheric chemistry. It initiates the reactions that break down airborne pollutants and helps to remove noxious chemicals such as sulfur dioxide and nitric oxide, which are poisonous gases, from the atmosphere.

Thus, having a full understanding of its sources and sinks is key to understanding and mitigating air pollution.

Kangwei Li et al, Spontaneous dark formation of OH radicals at the interface of aqueous atmospheric droplets, Proceedings of the National Academy of Sciences (2023). DOI: 10.1073/pnas.2220228120

In some cases, COVID-19 in pregnancy could harm the fetal brain

It's highly unlikely, but COVID-19 can be transmitted from mother to baby through the placenta, causing injury to the developing fetus' brain, a new study finds.

Researchers shared two unusual cases among hundreds of pregnant and delivering mothers they saw who were infected with COVID.

In both cases, the infants tested negative for COVID at birth, but had significantly elevated virus antibodies in their blood. This suggested that the antibodies had crossed the placenta or that the virus had passed to the baby and the immune response was the infant's.

Both infants had seizures, small head sizes and developmental delays. One died at 13 months.

Many women are affected by COVID-19 during pregnancy, but to see these kinds of problems in their infants at birth was clearly unusual.

Researchers are trying to understand what made these two pregnancies different, so they can direct research towards protecting vulnerable babies.

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The authors noted that early in the pandemic they observed transient lung disease and sometimes blood pressure issues among newborns born to mothers with COVID but who themselves had tested negative at birth.

This hinted at infection, the research authors said. It was unclear, however, whether the problems were caused by inflammatory placental cytokines or whether the virus had crossed the placenta and injured the baby. encephalopathy [brain damage caused by decreased blood flow].

But it wasn't lack of blood flow to the placenta that caused this. As best we can tell, it was the viral infection.

Analysis of both placentas clearly demonstrated severe inflammatory changes in each placenta, the authors said. The researchers were also struck by the absence of a critical placental hormone, human chorionic gonadotrophin. This hormone is essential for all fetal development, especially for brain development.

The authors noted that in both cases, the mothers contracted the infection in their second trimesters. Although they later cleared it, one had a repeat infection in her third trimester. This suggested an unusual maternal and/or fetal immune response to the virus.

 The U.S. Centers for Disease Control and Prevention has more on COVID-19 in pregnancy.

Merline Benny et al, Maternal SARS-CoV-2, Placental Changes and Brain Injury in 2 Neonates, Pediatrics (2023). DOI: 10.1542/peds.2022-058271

**

Bizarre Quantum Tunneling Observation Throws Out All the Rules

The strange phenomenon of quantum tunneling has been observed in a chemical reaction that defies classical physics

A chemical reaction is a bit like traveling from Vienna to Venice: your destination might be downhill, but to get there, you’ll need to cross the Alps. You can think of the energy changes molecules must go through as a landscape. Between the start and end of a reaction, this terrain can sometimes be so hilly that otherwise favorable reactions don’t happen at all if molecules lack the energy to make it over the bumps. Yet in some of these cases, such reactions do happen, thanks to quantum tunneling, which allows particles to occasionally bore through energy barriers they’d never be able to climb. This bizarre behavior is forbidden in traditional physics but allowed under the wild rules of quantum mechanics.

Now, in a new study published in Nature, scientists have managed to spot quantum tunneling in what classical physics would deem an impossible reaction between hydrogen molecules and deuterium ions—heavy, charged versions of hydrogen. This is the first time that researchers have managed to experimentally confirm a theoretical prediction about the rate of tunneling in a reaction involving ions. “Quantum mechanics in theory should be able to predict this [rate] very well,” says physicist Stephan Schlemmer of the University of Cologne in Germany, who was not involved in the study. “But nobody was sure whether this was really true.”

https://www.scientificamerican.com/article/bizarre-quantum-tunnelin...

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

Quantum tunnelling reactions play an important role in chemistry when classical pathways are energetically forbidden, be it in gas-phase reactions, surface diffusion or liquid-phase chemistry. In general, such tunnelling reactions are challenging to calculate theoretically, given the high dimensionality of the quantum dynamics, and also very difficult to identify experimentally. Hydrogenic systems, however, allow for accurate first-principles calculations. In this way the rate of the gas-phase proton-transfer tunnelling reaction of hydrogen molecules with deuterium anions, H₂ + D⁻ → H⁻ + HD, has been calculated, but has so far lacked experimental verification. Here we present high-sensitivity measurements of the reaction rate carried out in a cryogenic 22-pole ion trap. We observe an extremely low rate constant of (5.2 ± 1.6) × 10⁻²⁰ cm³ s⁻¹. This measured value agrees with quantum tunnelling calculations, serving as a benchmark for molecular theory and advancing the understanding of fundamental collision processes. A deviation of the reaction rate from linear scaling, which is observed at high H₂ densities, can be traced back to previously unobserved heating dynamics in radiofrequency ion traps.

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

Lithium in Drinking Water Identified as Potential Risk Factor For Autism

Study Pinpoints Specific Gut Bacteria Linked to Alzheimer's

Tensions between the brain, the gut, and the makeup of its microbial inhabitants appear to play a critical role in the development of neurodegenerative conditions. While evidence favoring a link between the microbiota-gut-brain axis (MGBA) and Alzheimer's disease continues to grow, the exact mechanism behind the relationship is still poorly understood.

The puzzle pieces have so far been frustratingly incoherent, involving seemingly unrelated factors as tangled proteins inside nervous tissue to suspect gut microbes to subtle differences in fat-transporting molecules.

Using the largest ever genome-wide association study of human gut microflora, a team of researchers from the US sought out a more explicit relationship between Alzheimer's disease and the mix of organisms living inside the digestive system.

Their analysis uncovered not only a genetic connection between different genera of gut bacteria and a diagnosis of Alzheimer's but also a link between the microbes and a genetic risk factor for the neurodegenerative disorder.

The study further emphasizes the interplay of genetic factors and inflammatory gut microflora in healthy brain function.

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Early in our development, our bodies are colonized by an assortment of bacteria, fungi, and viruses that strike a tentative truce with the immune system. For the most part, this arrangement is mutually beneficial. The microbes get a place to live, and we get a front-line defense of tiny occupants willing to protect their home.

That's not to say the balance is always a harmonious one. Shifts in our immune system can give some species an advantage over others. Likewise, changes in the makeup of microbes – by way of shifts in our diet, for example – can profoundly affect the body's functioning. For better and worse.

The tug-of-war between our microbial census and general health can ripple throughout the body in less than predictable ways, sowing confusion in how distant tissues identify friend and foe.

Part 1

In recent years, researchers have focused on this complex diplomacy between gut microflora, the immune system, and neurological functioning in an attempt to understand why areas of the brain degenerate and give rise to the symptoms of memory loss and cognitive decline we recognize as Alzheimer's disease.

Observational studies revealed a reduction in the diversity of gut microbes in individuals diagnosed with the condition, while laboratory analyses showed gut bacteria can release chemicals that could induce damaging inflammatory signals in the brain.

Complicating matters is a gene involved in the movement of fats through the blood known as apolipoprotein E (APOE). Of the three versions found in humans, a variant known as E4 appears to be a genetic risk for Alzheimer's. Why this is the case isn't clear, though there's good reason to suspect that having at least one copy of APOE E4 might hold some sway over the composition of our microbial citizens.

This latest exploration of the connections between microbes, APOE E4, and Alzheimer's provides even more compelling evidence of a mechanism at work in the gut.

An initial search of bacterial genes that could be associated with Alzheimer's revealed 20 genera suspected of playing some kind of role in the disease's development. A second hunt through a more constrained sample produced a slightly more certain 10 genera – six of which were fewer among diagnosed patients, and the remaining four being more common.

Of those 10 bacteria genera, four seemed to have a relationship with an APOE allele that is thought to raise the risk of Alzheimer's disease.

One example genus is the Actinobacterium Collinsella, which isn't only associated with Alzheimer's and the APOE variant but rheumatoid arthritis, atherosclerosis, and Type-2 diabetes as well.

The researchers suspect Collinsella's ability to promote the expression of inflammatory messenger hormones, together with its knack for making the gut more permeable, could play a role in exacerbating – if not triggering – neurological damage.

Elevated cholesterol and low-density lipoprotein (LDL) levels found in healthy adults with high numbers of Collinsella further show some link between microbes, fat metabolism, and neurodegeneration.

This is just one avenue for exploration; the research also uncovered 'protective' bacterial groups that could counter inflammation.

https://www.nature.com/articles/s41598-023-31730-5

Part 2

**

Researchers Studied a Circadian Clock in Real Time in a First For Science

We all have a built-in clock telling us when it's time to eat, time to sleep, and time to get up and do something with the day. Many organisms do, in fact, which is why it's such an important area of research for scientists.

Now the circadian clock and its responses to environmental cues has been studied in a way that has never been done before. Scientists were able to track the clock and its functions in real time, using a tiny aquatic organism called a cyanobacterium (Synechococcus elongatus). Given its clock works in a similar way to ours, it can tell us a thing or two about our own daily rhythms.

The team looked at the cyanobacterium's core oscillator – a nanomachine powered by three proteins that acts as a time regulator – studying the ways its output acts as a signal for timekeeping. The core 'oscillates' in response to different signal molecules binding to it throughout the day, resulting in the rhythmic expression of hundreds of genes within the cyanobacteria.

The new study analyzes how these interactions change when the cyanobacterium's clock 'resets' at the molecular level, something that could be compared to jet lag or daylight saving time adjustments for humans.

The research builds on an in vitro clock some members of the team had previously developed, one that could operate inside a test tube. Through new advancements in the way the clock is monitored and run, the team was able to get real-time readings as the timing settings were adjusted and responded to.

This revealed several new insights, including the fact enzymes known as kinases that mediate genetic expression are more closely related to the clock function than previously thought.

Part 1

For the first two decades after its discovery, most of the research has been centered on the core oscillator. it 's now found that the kinases, previously thought to be just output components, are actually part of the whole clock.

The core oscillator is often thought of as the 'gears' of the circadian clock and the kinases as the 'hands', with both required to tell the right time. What this study shows is how they're both needed – and how closely linked the inputs and outputs of the clock are.

If you don't have both hands they don't set time correctly because one of them is a stabilizer and one a perturber to the resetting signal, and you need both."

To put it another way, in retrieving information from the clock, the kinases also interfere with it. It was also shown that two kinases are needed to properly respond to a 'reset' signal, as might happen when we move through time zones.

Now that this method of real-time monitoring has been established, it can be used to better understand how our own internal circadian rhythms work, and how their timekeeping has an effect on the rest of our bodies.

https://www.pnas.org/doi/10.1073/pnas.2221453120

Part 2

A unique behaviour of elephants discovered: Elephants can self-teach some things - like peeling bananas - by observing their care-takers!

Elephants like to eat bananas, but they don't usually peel them first in the way humans do. A new report published in the journal Current Biology on April 10, however, shows that one very special Asian elephant named Pang Pha picked up banana peeling all on her own while living at the Berlin Zoo. She reserves it for yellow-brown bananas, first breaking the banana before shaking out and collecting the pulp, leaving the thick peel behind.

This was discovered by researchers  after learning from Pha's caretakers about her unusual banana-peeling talent. At first, they were confused. They brought Pha nice yellow and green bananas, and she never peeled them.

It was only when they understood that she peels only yellow-brown bananas that their project took off.

When yellow-brown bananas are offered to a group of elephants, Pha changes her behavior, they report. She eats as many bananas as she can whole and then saves the last one to peel later.

Banana-peeling appears to be rare in elephants as far as anyone knows, and none of the other Berlin elephants engage in peeling. It's not clear why Pha peels them. The researchers note, however, that she was hand raised by human caretakers in the Berlin Zoo. They never taught her to peel bananas, but they did feed her peeled bananas.

Based on this, the researchers suggest she acquired peeling through observational learning from humans. Earlier reports on African elephants suggest elephants can interpret human pointing gestures and classify people into ethnic groups, but complex human-derived manipulation behaviours, like banana-peeling, appear rather unique, according to the researchers. The findings in Pha nevertheless suggest that elephants overall have surprising cognitive abilities and impressive manipulative skill.

Elephants have truly remarkable trunk skills and that their behavior is shaped by experience.

The researchers find it surprising that Pha alone picked up on banana peeling. It leads them to wonder if such habits are normally passed on through elephant families. They're now looking into other sophisticated trunk behaviors, such as tool use.

Wataru Brecht, Elephant Banana Peeling, Current Biology (2023). DOI: 10.1016/j.cub.2023.02.076. www.cell.com/current-biology/f … 0960-9822(23)00266-X

Is there a limit to  scientists' capabilities? NO?!

Here is more evidence!

Scientists map gusty winds in a far-off neutron star system

An accretion disk is a colossal whirlpool of gas and dust that gathers around a black hole or a neutron star like cotton candy as it pulls in material from a nearby star. As the disk spins, it whips up powerful winds that push and pull on the sprawling, rotating plasma. These massive outflows can affect the surroundings of black holes by heating and blowing away the gas and dust around them.

At immense scales, "disk winds" can offer clues to how supermassive black holes shape entire galaxies. Astronomers have observed signs of disk winds in many systems, including accreting black holes and neutron stars. But to date, they've only ever glimpsed a very narrow view of this phenomenon.

Now, MIT astronomers have observed a wider swath of winds, in Hercules X-1, a system in which a neutron star is drawing material away from a sun-like star. This neutron star's accretion disk  is unique in that it wobbles, or "precesses," as it rotates. By taking advantage of this wobble, the astronomers have captured varying perspectives of the rotating disk and created a two-dimensional map of its winds, for the first time.

The new map reveals the wind's vertical shape and structure, as well as its velocity—around hundreds of kilometers per second, or about a million miles per hour, which is on the milder end of what accretion disks can spin up.

If astronomers can spot more wobbling systems in the future, the team's mapping technique could help determine how disk winds influence the formation and evolution of stellar systems, and even entire galaxies.

Peter Kosec, Vertical wind structure in an X-ray binary revealed by a precessing accretion disk, Nature Astronomy (2023). DOI: 10.1038/s41550-023-01929-7. www.nature.com/articles/s41550-023-01929-7

Engineered plants produce sex perfume to trick pests and replace pesticides

By using precision gene engineering techniques, researchers at the Earlham Institute in Norwich have been able to turn tobacco plants into solar-powered factories for moth sex pheromones.

Critically, they've shown how the production of these molecules can be efficiently managed so as not to hamper normal plant growth.

Pheromones are complex chemicals produced and released by an organism as a means of communication. They allow members of the same species to send signals, which includes letting others know they're looking for love.

Farmers can hang pheromone dispersers among their crops to mimic the signals of female insects, trapping or distracting the males from finding a mate. Some of these molecules can be produced by chemical processes but chemical synthesis is often expensive and creates toxic byproducts.

Synthetic biology applies engineering principles to the building blocks of life, DNA. By creating genetic modules with the instructions to build new molecules, researchers  can turn a plant such as tobacco into a factory that only needs sunlight and water.

Synthetic biology can allow us to engineer plants to make a lot more of something they already produced, or we can provide the genetic instructions that allow them to build new biological molecules, such as medicines or these pheromones.

Now they have engineered the tobacco plant to produce  moth sex pheromones. 

The same plant has previously been engineered to produce ebola antibodies and even coronavirus-like particles for use in COVID vaccines.

The Group built new sequences of DNA in the lab to mimic the moth genes and introduced a few molecular switches to precisely regulate their expression, which effectively turns the manufacturing process on and off.

An important component of the new research was the ability to fine tune the production of the pheromones, as coercing plants to continuously build these molecules has its drawbacks: As researchers increase the efficiency, too much energy is diverted away from normal growth and development.

However, this new research provides a way to regulate gene expression with much more subtlety

In the lab, the team set about testing and refining the control of genes responsible for producing the mix of specific molecules that mimic the sex pheromones of moth species, including navel orange worm and cotton bollworm moths. They showed that copper sulfate could be used to finely tune the activity of the genes, allowing them to control both the timing and level of gene expression. This is particularly important as copper sulfate is a cheap and readily-available compound already approved for use in agriculture. They were even able to carefully control the production of different pheromone components, allowing them to tweak the cocktail to better suit specific moth species. The researchers  have shown they can control the levels of expression of each gene relative to the others.

Nicola Patron et al, Tunable control of insect pheromone biosynthesis in Nicotiana benthamiana, Plant Biotechnology (2023).

Identifying cancer genes' multiple personalities

Mutations in our genes can lead to severe problems, like colon or liver cancer. But cancer is very complex. Mutations in the same genes can lead to different subtypes of tumors in different people. Currently, scientists don't have a good way to produce such tumor subtypes for study in the lab.

13 volcanoes seen from space

Have you ever wondered what a volcano looks like from space? Today, we’re counting down our picks of the most impressive volcanoes around the world – captured by satellites.

Graviton to photon conversion via parametric resonance: Physicists discover that gravity can create light

Researchers have discovered that in the exotic conditions of the early universe, waves of gravity may have shaken space-time so hard that they spontaneously created radiation.

The physical concept of resonance surrounds us in everyday life. When you're sitting on a swing and want to go higher, you naturally start pumping your legs back and forth. You very quickly find the exact right rhythm to make the swing go higher. If you go off rhythm then the swing stops going higher. This particular kind of phenomenon is known in physics as a parametric resonance.

Your legs act as an external pumping mechanism. When they match the resonant frequency of the system, in this case your body sitting on a swing, they are able to transfer energy to the system making the swing go higher.

These kinds of resonances happen all over the place, and a team of researchers have discovered that an exotic form of parametric resonance may have even occurred in the extremely early universe. 

Perhaps the most dramatic event to occur in the entire history of the universe was inflation. This is a hypothetical event that took place when our universe was less than a second old. During inflation our cosmos swelled to dramatic proportions, becoming many orders of magnitude larger than it was before. The end of inflation was a very messy business, as gravitational waves sloshed back and forth throughout the cosmos.

Normally gravitational waves are exceedingly weak. We have to build detectors that are capable of measuring distances less than the width of an atomic nucleus to find gravitational waves passing through the Earth. But researchers have pointed out that in the extremely early universe these gravitational waves may have become very strong.

And they may have even created standing wave patterns where the gravitational waves weren't traveling but the waves stood still, almost frozen in place throughout the cosmos. Since gravitational waves are literally waves of gravity, the places where the waves are the strongest represent an exceptional amount of gravitational energy.

The researchers found that this could have major consequences for the electromagnetic field existing in the early universe at that time. The regions of intense gravity may have excited the electro magnetic field enough to release some of its energy in the form of radiation, creating light.

This result gives rise to an entirely new phenomenon: the production of light from gravity alone. There's no situation in the present-day universe that could allow this process to happen, but the researchers have shown that the early universe was a far stranger place than we could possibly imagine.

Graviton to photon conversion via parametric resonance

https://www.sciencedirect.com/science/article/pii/S2212686423000365...

Cameras never lie. Really?

Ask AI, They do! 

The camera never lied... until AI told it to

An amateur photographer who goes by the name "ibreakphotos" decided to do an experiment on his Samsung phone last month to find out how a feature called "space zoom" actually works.

The feature, first released in 2020, claims a 100x zoom rate, and Samsung used sparkling clear images of the Moon in its marketing.

Ibreakphotos took his own pictures of the Moon—blurry and without detail—and watched as his phone added craters and other details.

The phone's artificial intelligence software was using data from its "training" on many other pictures of the Moon to add detail where there was none.

"The Moon pictures from Samsung are fake," he wrote, leading many to wonder whether the shots people take are really theirs anymore—or if they can even be described as photographs.

Samsung has defended the technology, saying it does not "overlay" images, and pointed out that users can switch off the function.

The firm is not alone in the race to pack its smartphone cameras with AI—Google's Pixel devices and Apple's iPhone have been marketing such features since 2016.

The AI can do all the things photographers used to labor over—tweaking the lighting, blurring backgrounds, sharpening eyes—without the user ever knowing.

But it can also transform backgrounds or simply wipe away people from the image entirely.

And the debate over AI is not limited to hobbyists on message boards—professional bodies are raising the alarm too.

Part 1

The industry is awash with AI, from cameras to software like Photoshop.

This automation is increasingly blurring boundaries between a photograph and a piece of artwork.

The nature of AI is different to previous innovations, .

because the technology can learn and bring new elements beyond those recorded by film or sensor.

This brings opportunities but also "fundamental challenges around redefining what photography is, and how 'real' a photograph is.

What professional photographers are most concerned about, though, is the rise of AI tools that generate completely new images.

Source: 2023 AFP

https://techxplore.com/news/2023-04-camera-ai-told.html?utm_source=...

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Part 2