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

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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

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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

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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

India's tiger population rises above 3,000

India's wild tiger population—by far the largest in the world—has risen above 3,000, according to a census released Sunday, boosting efforts to conserve the endangered species.

The largest of all cats, tigers once roamed throughout central, eastern and southern Asia.

But in the past 100 years the tiger has lost more than 93 percent of its historic range and now only survives in scattered populations in 13 countries, according to the International Union for Conservation of Nature (IUCN).

The Indian census estimated there were 3,167 tigers in the wild across the country, up from 2,967 reported in the last such exercise.

Surveys are conducted every four years, using camera traps and computer programmes to individually identify each creature.

The rate of increase has slowed to less than seven percent over the period, down from more than 30 percent in the previous four years.

Deforestation, poaching and human encroachment on habitats have devastated tiger populations across Asia .

India is now home to 75 percent of the global tiger population and also the "largest tiger range country in the world".

In 1900, more than 100,000 tigers were estimated to roam the planet. But that fell to a record low of 3,200 in 2010.

That year, India and 12 other countries with tiger populations signed an agreement to double their big cat numbers by 2022.

India is believed to have had a tiger population of around 40,000 at the time of independence from Britain in 1947.

That fell over subsequent decades to about 3,700 in 2002 and an all-time low of 1,411 four years later, but numbers have since risen steadily.

On the other hand it also tells us that each of us now need to work harder to restore degraded habitats, ensure safe movement of tigers through corridors and promote coexistence.

Source: News agencies

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 Link between youthful gut microbiota and potential centenarians

With a growing body of scientific evidence illustrating the influence of gut microbiota on human health, researchers investigated the microflora inhabiting the guts of the world's healthiest people—centenarians.

In the paper, "Longevity of centenarians is reflected by the gut microbiome with youth-associated signatures," published in Nature Aging, the researchers studied the microbiomes of 1,575 individuals aged 20 up to 117, with 297 of them reported to be 100 years old or older. A Research Briefing on the study, titled "Youth-associated signatures in the gut microbiome of centenarians," has been published in the same journal issue.

Participants were evaluated in five age-related groups. Young adults (n = 314, 20–44 years), a middle-aged group (n = 277, 45–65 years), old adults (n = 386, 66–85 years), a nonagenarian group (n = 301, 90–99 years), and a centenarian cohort (n = 297, 100–117 years).

The researchers discovered that the gut microbiome signature in centenarians resembles that of young adults with an overrepresentation of Bacteroides spp., an increase in species evenness (species have a similar abundance), an enrichment of potentially beneficial species from the Bacteroidetes phylum and depletion of potential pathobionts (harmless but can become pathogenic under certain circumstances).

A smaller group of 45 centenarians was tested twice over a year and a half. Results from the group indicated that as centenarians age, the signature species evenness and low pathobionts continued to develop and were enhanced or conserved.

The researchers propose that this microbiome signature is associated with longevity, as they observed in their study, and state that this may counteract the senescence or chronic diseases that generally accompany aging, which this study could not have observed.

The researchers are currently isolating thousands of bacteria strains from the centenarians and testing their benefits on animal models in search of microorganisms that are able to extend the human lifespan. 

Shifu Pang et al, Longevity of centenarians is reflected by the gut microbiome with youth-associated signatures, Nature Aging (2023). DOI: 10.1038/s43587-023-00389-y

Youth-associated signatures in the gut microbiome of centenarians, Nature Aging (2023). DOI: 10.1038/s43587-023-00395-0

Evidence found of possible interdomain horizontal gene transfer leading to development of the eye in vertebrates

A group of molecular and chemical biologists,  has found possible evidence of interdomain horizontal gene transfer leading to the development of the eye in vertebrates. In their study, reported in Proceedings of the National Academy of Sciences researchers used the IQ-TREE software program to trace the evolutionary history of genes associated with vision.

Ever since scientists proved that humans, along with other animals, developed due to evolutionary processes, one problem has stood out—how could evolution possibly account for the development of something as complicated as the eyeball? Even Charles Darwin was said to be stumped by the question. In recent times, this seeming conundrum has been used by some groups as a means to discredit evolutionary theory altogether. In this new effort, researchers sought to answer the question once and for all.

Their work began with the idea that vision in vertebrates may have got its start by using light-sensitive genes transferred from microbes. To find out if that might be the case, the team submitted likely human gene candidates to the IQ-TREE program to look for similar genetic sequences in other creatures, most specifically, microbes.

They found a promising candidate, a gene called IRBP. In humans, it encodes for a protein that is used in the eye as part of a process that converts light into electrical pulses that are eventually sent to the brain via the optic nerve. The research team notes that the gene is an essential component of vision in all vertebrates. IRBP is also found in microbes, most specifically in bacterial peptidases, a class of enzymes that is known for recycling proteins.

The researchers note that while IRBP and the protein that it encodes exists in all vertebrates, it does not exist in most invertebrates. This, they suggest, indicates that the IRBP gene may have been transferred from a microbe over 500 million years ago to an ancient vertebrate, leading to the development of light sensitivity, and over time, to organs such as eyeballs.

Geoscientist discovers new phosphorus material after lightning strike

After lightning struck a tree in a New Port Richey neighborhood, a University of South Florida professor discovered the strike led to the formation of a new phosphorus material. It was found in a rock—the first time in solid form on Earth—and could represent a member of a new mineral group.

Minerals similar to it can be found in meteorites and space, but can't be  seen this exact material anywhere on Earth.

High-energy events, such as lightning, can cause unique chemical reactions, and in this instance, result in a new material—one that is transitional between space minerals and minerals found on Earth.

When lightning strikes a tree, the ground typically explodes out and the surrounding grass dies, forming a scar and sending electric discharge through nearby rock, soil and sand, forming fulgurites, also known as 'fossilized lightning'.

In wet environments, such as in Florida,  iron will often accumulate and encrust tree roots. In this case, not only did the lightening strike combust the iron on the tree roots, but it combusted the naturally occurring carbon in the tree as well. The two elements led to a chemical reaction that created a fulgurite that looked like a metal 'glob.'

Inside the fulgurite, a colorful, crystal-like matter revealed a material never before discovered.

The experiment, when repeated in a lab,  was unsuccessful and indicates the material likely forms quickly under precise conditions, and if heated too long, will turn into the mineral found in meteorites.

This research may reveal other forms of reduced minerals are plausible and many could have been important in the development of life on Earth.

Luca Bindi et al, Routes to reduction of phosphate by high-energy events, Communications Earth & Environment (2023). DOI: 10.1038/s43247-023-00736-2

A day and night difference: Molecular composition of aerosols diffe...

Tiny aerosols particles in the atmosphere have a significant effect on the climate. They affect the climate directly by interacting with solar radiation. Depending on the type of particle, they can block sunlight, cooling the atmosphere, or absorb sunlight, warming the atmosphere. They also affect climate indirectly by acting as seeds for warm and cold cloud formation. But scientists lack information on these aerosols' molecular composition. This is especially true of aerosols during the day and night above agricultural fields.

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How air pollution causes lung cancer

Air pollution might cause lung cancer by creating inflammation that encourages proliferation of cells with e... — not by mutating DNA itself. The results provide a mechanism that could apply to other cancers caused by environmental exposure and might one day lead to ways to prevent them. “The idea is that exposures to carcinogens could promote cancer without actually doing anything to the DNA,” says medical geneticist Serena Nik-Zainal. “Not every carcinogen is a mutagen.”

Environmental particulate matter measuring ≤2.5 μm (PM_2.5), known to be associated with lung cancer risk, promotes lung cancer by acting on cells that harbour pre-existing oncogenic mutations in healthy lung tissue.

https://www.nature.com/articles/s41586-023-05874-3?utm_source=Natur...

Researchers leverage cell self-destruction to treat brain tumours

Glioblastoma is the most common type of brain tumor in adults. The disease is 100% fatal and there are no cures, making it the most aggressive type of cancer. Such a poor prognosis has motivated researchers and neurosurgeons to understand the biology of tumors with the goal of creating better therapies.

A team of researchers have found that glioblastoma tumor cells are particularly sensitive to ferroptosis—a type of cell death that can be triggered by removing certain amino acids from the diet.

First, the researchers found that when they take away certain amino acids in animal models that the glioblastoma cells are more likely to die by ferroptosis. Secondly, they found that removing these amino acids makes the drugs a lot more effective at inducing ferroptosis in cancer cells.

Ferroptosis is an iron-dependent type of "programmed cell death" or a biological process that causes cells to "self-destruct" on command. Our bodies don't need to kill cells unless absolutely necessary, so the process is tightly controlled by certain biological mechanisms. However, researchers are only now beginning to comprehend the process because ferroptosis was recognized only a decade ago.

Every cell has certain safety features to keep it from going through ferroptosis in an unpredictable way. Two amino acids, cysteine and methionine, are critical for preventing the process from starting in cells. We typically pick up these amino acids through our diet.

By depriving animal models of cysteine and methionine through a customized diet, they found that the glioblastoma cells were significantly more likely to die via ferroptosis. They also found that the diet made their chemotherapy drugs more apt at initiating programmed cell death, meaning that very low doses were able to achieve a more potent effect than before. Ultimately, the animal models had improved survival after going on the diet.

This type of diet has also shown to be very effective in sarcoma, lung cancers, and pancreatic cancers, so there is hope that this diet can be used to put some extra umph behind chemotherapy and/or surgery to remove tumors throughout the body.

Pavan S. Upadhyayula, Dominique M. Higgins, Angeliki Mela, Matei Banu, Athanassios Dovas, Fereshteh Zandkarimi, Purvi Patel, Aayushi Mahajan, Nelson Humala, Trang T. T. Nguyen, Kunal R. Chaudhary, Lillian Liao, Michael Argenziano, Tejaswi Sudhakar, Colin P. Sperring, Benjamin L. Shapiro, Eman R. Ahmed, Connor Kinslow, Ling F. Ye, Markus D. Siegelin, Simon Cheng, Rajesh Soni, Jeffrey N. Bruce, Brent R. Stockwell, Peter Canoll. Dietary restriction of cysteine and methionine sensitizes gliomas to ferroptosis and induces alterations in energetic metabolism. Nature Communications, 2023; 14 (1) DOI: 10.1038/s41467-023-36630-w

New 'AI scientist' combines theory and data to discover scientific equations

In 1918, the American chemist Irving Langmuir published a paper examining the behavior of gas molecules sticking to a solid surface. Guided by the results of careful experiments, as well as his theory that solids offer discrete sites for the gas molecules to fill, he worked out a series of equations that describe how much gas will stick, given the pressure.

Now, about a hundred years later, an "AI scientist" developed by researchers at IBM Research, Samsung AI, and the University of Maryland, Baltimore County (UMBC) has reproduced a key part of Langmuir's Nobel Prize-winning work. The system—artificial intelligence (AI) functioning as a scientist—also rediscovered Kepler's third law of planetary motion, which can calculate the time it takes one space object to orbit another given the distance separating them, and produced a good approximation of Einstein's relativistic time-dilation law, which shows that time slows down for fast-moving objects.

A paper describing the results is published in Nature Communications on April 12.

Combining Data and Theory for Derivable Scientific Discovery with AI-Descartes, Nature Communications (2023). DOI: 10.1038/s41467-023-37236-y

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Time-restricted fasting could cause fertility problems

Time-restricted fasting diets could cause fertility problems according to new research.

Time-restricted fasting is an eating pattern where people limit their food consumption to certain hours of the day. It's a popular health and fitness trend and people are doing it to lose weight and improve their health.

 A new study published recently in Proceedings of the Royal Society B: Biological Sciences shows that time-restricted fasting affects reproduction differently in male and female zebrafish. It is titled, "Fasting increases investment in soma upon refeeding at the cost of gamete quality in zebrafish."

Importantly, some of the negative effects on eggs and sperm quality can be seen after the fish returned to their normal levels of food consumption.

The research team say that while the study was conducted in fish, their findings highlight the importance of considering not just the effect of fasting on weight and health, but also on fertility.

The way organisms respond to food shortages can affect the quality of eggs and sperm, and such effects could potentially continue after the end of the fasting period.

Fasting increases investment in soma upon refeeding at the cost of gamete quality in zebrafish, Proceedings of the Royal Society B: Biological Sciences (2023). DOI: 10.1098/rspb.2022.1556. royalsocietypublishing.org/doi … .1098/rspb.2022.1556

Mitochondria power supply failure may cause age-related cognitive impairment

Brains are like puzzles, requiring many nested and co-dependent pieces to function well. The brain is divided into areas, each containing many millions of neurons connected across thousands of synapses. These synapses, which enable communication between neurons, depend on even smaller structures: message-sending boutons (swollen bulbs at the branch-like tips of neurons), message-receiving dendrites (complementary branch-like structures for receiving bouton messages), and power-generating mitochondria. To create a cohesive brain, all these pieces must be accounted for.

The team found that adherence to the ultrastructural size principle was essential for avoiding working memory impairment with age. By viewing violation of the ultrastructural size principle and mitochondria-related failures as the key to age-related cognitive impairment, the study ushers in a new era for aging research.

 Violation of the ultrastructural size principle in the dorsolateral prefrontal cortex underlies working memory impairment in the aged common marmoset (Callithrix jacchus), Frontiers in Aging Neuroscience (2023). DOI: 10.3389/fnagi.2023.1146245

Part 2

Predictive power of climate models may be masked by volcanoes

Simulated volcanic eruptions may be blowing up our ability to predict near-term climate, according to a new study published in Science Advances.

The research, led by the National Center for Atmospheric Research (NCAR), finds that the way volcanic eruptions are represented in climate models may be masking the models' ability to accurately predict variations in sea surface temperatures in the tropical Pacific that unfold over multiple years to a decade. These decadal variations in sea surface temperatures in the tropical Pacific are linked to climate impacts across the globe, including variations in precipitation and severe weather. Accurate predictions, therefore, could provide community leaders, farmers, water managers, and others with critical climate information that allows them to plan years in advance.

Because it is well established that large volcanic eruptions can have significant, long-term cooling effects on the climate, researchers expected that the collection of simulations that included the volcanic eruptions would produce more accurate multiyear and decadal climate predictions. Instead, they found that the inclusion of the eruptions degraded the model's predictive capabilities, at least in the tropical Pacific, an area that is especially important because of the connections between sea surface temperatures and near-term climate events.

For example, the simulations that included the volcanoes predicted a subsequent cooling of the sea surface temperatures in the tropical Pacific after the eruptions. In reality, that region of the ocean warmed, a change that was well predicted by the simulations that did not include the volcanic eruptions.

These findings highlight the difficulty of accurately representing the complex climate impacts that follow a volcanic eruption  in a model, a task made more challenging because researchers only have a few real-life examples in the observational record. Scientists know that volcanoes can loft sulfur gases high into the stratosphere where they can transform into sunlight-reflecting aerosols. But how the resulting cooling ultimately affects the entire Earth system, including sea surface temperatures, is not well understood.

Xian Wu, Volcanic forcing degrades multiyear-to-decadal prediction skill in the tropical Pacific, Science Advances (2023). DOI: 10.1126/sciadv.add9364. www.science.org/doi/10.1126/sciadv.add9364

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Viruses: How avian influenza viruses spill over to mammals

Picture your local lake covered with migrating geese, ducks or other waterfowl. Even though you don’t hear any coughing, you might well be witnessing ‘flu season’ for birds. Influenza viruses cause gastrointestinal infections in birds, and are spread when birds defecate in water that other birds then drink .Sometimes, however, avian influenza viruses make their way into mammals, including humans, and cause respiratory infections: how does this happen?

Waterfowl are the main natural reservoir for influenza viruses, and influenza viruses that infect humans and other mammals originally came from birds. This spillover can happen in two ways. The first way involves special mammalian hosts (like pigs) that can be infected by both avian and mammalian influenza viruses . Occasionally, an individual from one of these species becomes simultaneously infected with both types of virus, and the two viruses exchange gene segments to form a novel virus that retains the ability to infect mammals. This process – which is known as gene reassortment – is what happened to start human influenza pandemics in 1957 and 1968 .

The second way that spillover can happen involves a mammal getting directly infected with a bird virus . This individual then transmits this bird virus to others in its same species. If infection of the new species is sustained over time and within many individuals, the avian virus will experience natural selection for genetic mutations that make it more and more compatible with the mammalian species.

 https://elifesciences.org/articles/86051?utm_source=content_alert&a...

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Study unveils neural processes underpinning the re-emergence of consciousness after anesthesia

Before undergoing surgeries and other invasive medical procedures, patients typically undergo anesthesia. Anesthesia consists in giving patients a class of drugs (i.e., anesthetics) that cause them to lose feeling in specific areas of the body (i.e., local anesthesia) or fully lose awareness during a procedure (i.e., general anesthesia). These anesthetics can be administered to patients via injection, inhalation, skin-numbing lotions, and other means.

In the past, doctors and medical researchers viewed general anesthesia as a passive process that could not be influenced or interrupted once anesthetic drugs were administered. More recently, however, studies showed that it is in fact an active brain process that can be experimentally controlled and acted on. A research team  recently carried out a study investigating the processes underpinning brain states while under general anesthesia and those associated with the subsequent re-emergence of awareness. Their findings, published in Nature Neuroscience, highlight possible strategies that could help anesthesiologists to extend and deepen or shorten periods of anesthesia.

In the experiments with mice , when the brain is forced into a minimum responsive state by diverse anesthetics, a rapid downregulation of K⁺/Cl⁻ cotransporter 2 (KCC2) in the ventral posteromedial nucleus (VPM) serves as a common mechanism by which the brain regains consciousness.

To examine the neural processes linked to the re-emergence of consciousness after anesthesia, the researchers carried out a series of experiments on adult mice. They gave the mice one of three different anesthetic drugs (i.e., ketamine, propofol and pentobarbital) and then looked at the molecular mechanisms that emerged while they were re-gaining awareness.

To assess the mice's levels of consciousness they measured the so-called loss of righting reflex (LORR), a point in which animals no longer act on their instinct to avoid laying with their stomach facing up. In addition, they observed the animals' behavioral responses to external stimuli.

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The team's experiments yielded interesting results, identifying a new neuronal and molecular mechanism through which the brain re-gains consciousness after general anesthesia. They also showed that the ventral posteromedial nucleus (VPN), part of the thalamus, is a key brain region associated with re-emergence of consciousness.

Ubiquitin-proteasomal degradation is responsible for KCC2 downregulation, which is driven by ubiquitin ligase Fbxl4. Phosphorylation of KCC2 at Thr1007 promotes interaction between KCC2 and Fbxl4. KCC2 downregulation leads to γ-aminobutyric acid type A receptor-mediated disinhibition, enabling accelerated recovery of VPM neuron excitability and emergence of consciousness from anesthetic inhibition. This pathway to recovery is an active process and occurs independent of anesthetic choice.

Overall, the recent work by this team of researchers shows that the degradation of KCC2 transporter neurons located in the VPM, through the means of ubiquitin, a compound in living cells that contributes to the degradation of superfluous or faulty proteins in the brain, is a key step in the mice's emergence of consciousness after general anesthesia. This key finding could potentially inform the development of strategies to wake patients who are in a  vegetative state or minimally conscious state, which is a long-standing medical challenge.

Jiang-Jian Hu et al, Emergence of consciousness from anesthesia through ubiquitin degradation of KCC2 in the ventral posteromedial nucleus of the thalamus, Nature Neuroscience (2023). DOI: 10.1038/s41593-023-01290-y

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Preventing dangerous blood clots

Hibernating bears, paralyzed humans, and pigs kept in small enclosures all avoid dangerous blood clots, despite being immobile for extremely long periods. Recent research shows that reduction of a key protein prevents the formation of blood clots in all three mammal species when they are still for days, weeks, months, or even years at a time. The study is published recently (April 13, 2023), in Science.

If you've ever taken a long haul flight, you might have taken advice to prevent a dangerous blood clot—deep vein thrombosis—from forming in one or both of your legs, while you sit still for multiple hours. Perhaps you set a reminder to get up and walk around, and you wore compression socks to keep the blood from pooling in your legs.

Most people won't experience a clot if they take care on a flight, but there is a serious risk for some people who are pre-disposed to blood clots due to genetic factors.

The discovery that a protein known as Hsp47 is dramatically reduced—by 55 times—when someone is immobilized for a much longer period than a flight, could lead to new medicines to help those who have inherited blood clotting disorders that put them at risk for pulmonary embolism, heart attack, and stroke.

It seems counterintuitive that people who have severe paralysis don't appear to be at higher risk of blood clots. This tells us that something interesting is happening. And it turns out that reducing levels of Hsp47 plays a key role in preventing clots, not just in humans, but in other mammals, including bears and pigs.

"When we see something like this in multiple species, that reinforces its importance. Having Hsp47 must have been an evolutionary advantage."

Hsp47 is released by platelets—the sticky blood cells that trigger blood clotting. Usually clotting is an important response to an injury, to prevent blood loss, and Hsp47 is one of the necessary ingredients to enable platelets to do their job. Examining the role of Hsp47 in clotting function the team found that when released into the blood of bears, mice and humans that it promoted conditions that may give rise to deep vein thrombosis.

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It appears that there is something about movement that keeps Hsp47 at an appropriate level. It could be that the mechanical forces involved in moving around actually have an impact on gene expression, dramatically increasing the amount of Hsp47 that circulates in the blood.
Now we know that Hsp47 is so important, we can begin to look for new or existing medicines that might be able to inhibit the function of this protein in blood clotting and protect mobile people who are prone to clots.

Manuela Thienel et al, Immobility-associated thromboprotection is conserved across mammalian species from bear to human, Science (2023). DOI: 10.1126/science.abo5044. www.science.org/doi/10.1126/science.abo5044

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