Cap top 20% of energy users to reduce carbon emissions, say scientists

Consumers in the richer, developed nations will have to accept restrictions on their energy use if international climate change targets are to be met, warn researchers.

The big challenge is to identify the fairest and most equitable way that governments can curtail energy use, a process known as energy demand reduction. In the paper, "Emissions savings from equitable energy demand reduction," in the journal Nature Energy, the research team analyzed several scenarios to identify a potential solution.

One option is to cap the top 20% of energy users while allowing those people who use little energy and have poverty-level incomes to be able to increase their consumption levels and improve their quality of life.

Across any population there will be a range—or distribution—of values for how much energy individuals use. The values are sorted into 100 percentiles—for example, the 50th percentile represents the value that is exactly in the middle of the energy distribution, which half the population fail to reach and the other half exceeds.

Under the energy demand reduction scheme, the top-level energy users would see their energy use restricted to the value of energy use at the 80th percentile. In the scenario modeled, that would be 170.2 gigajoules (GJ) per person per year, compared to the mean energy use of the top 20% of consumers of 196.8 GJ per person per year.

Using data from 27 European states, the researchers modeled how effective this energy demand reduction strategy would be. They found it would cut greenhouse gas emissions by 11.4% from domestic energy sources; 16.8% from transport and 9.7% from total energy consumption.

Allowing people in poverty to increase their energy use would reduce these emissions savings by relatively small amounts—1.2 percentage points for domestic energy; 0.9 for transport; and 1.4 for total energy consumption. It would enable the less well-off to meet unmet needs, perhaps where they may have been unable to adequately heat their home.

Part 1

Policymakers need to win public support for energy demand reduction mechanisms. The reality is decarbonization on the supply side, where energy is generated and distributed, will not be enough to deliver the emission reductions that are needed.

"So, energy demand will have to be reduced. That is the inescapable reality. Experts on the UN's Intergovernmental Panel on Climate Change estimate that reducing energy demand could produce between 40% and 70% of the emissions reductions that need to be found by 2050.

This research is indicating that public support for energy demand reduction is possible if the public see the schemes as being fair and deliver climate justice.

Milena Büchs, Emissions savings from equitable energy demand reduction, Nature Energy (2023). DOI: 10.1038/s41560-023-01283-y. www.nature.com/articles/s41560-023-01283-y

Part 2

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'Mind controlling' parasitic worms are missing genes found in every other animal, researchers find

In a world full of bizarre animals, hairworms are some of the strangest. Hairworms are parasitic worms that manipulate the behavior of their hosts in what's sometimes called "mind control."

A new study in the journal Current Biology reveals another strange trait shared by different hairworm species—they're missing about 30% of the genes that researchers expected them to have. What's more, the missing genes are responsible for the development of cilia, the hair-like structures present in at least some of the cells of every other animal known.

Hairworms are found all over the world, and they look like skinny strands of spaghetti, a couple inches long. Their simple bodies hint at their parasitic lifestyle— they have no excretory, respiratory, or circulatory systems, and they spend almost their entire lives inside the bodies of other animals.

One of the coolest things, maybe the thing that they are most known for, is that they can affect the behavior of their hosts and make them do things that they wouldn't do otherwise.

There are a few hundred species of freshwater hairworms. Their eggs hatch in water, and the hairworm larvae get eaten by tiny water-dwelling predators like mayfly larvae, which in turn get eaten by bigger, land-dwelling predators like crickets.

After growing into adulthood inside of their new hosts' bodies, the hairworms manipulate the hosts' behavior, causing them to jump into water. There, the worms swim out of their hosts' butts and seek out mates, knotting themselves together, to begin the cycle anew.

There are also five species of hairworms that live in marine environments and parasitize water-dwelling creatures like lobsters, but it's not clear if those ones also have host manipulation capabilities— there's no pressure for the worms to get back to the water, since the hosts already live there.

Researchers d sequenced them. But when they compared the hairworms' genetic codes to those of other animals, they found something striking.

"What they found was very surprising: both hairworm genomes were missing about 30% of a set of genes that are expected to be present across basically all groups of animals.

The large majority of the missing genes were exactly the same between the two species. This was just implausible by chance.

Part 1

What's more, the fact that both the freshwater and marine hairworm species had lost the genes for cilia indicates that this evolutionary change happened in the deep past to the two species' common ancestor. "It is likely that the loss happened early on in the evolution of the group, and they just have been carrying on like that.

The finding opens the door to several new questions. It's not clear how the lack of cilia have affected hairworms, or if the hairworms' parasitic behavior could be related to the missing cilia. There are plenty of other parasitic organisms that aren't missing these specific genes, so we cannot say that the genes are missing because of their parasitic lifestyle. 

 Tauana J Cunha, Rampant loss of universal metazoan genes revealed by a chromosome-level genome assembly of the parasitic Nematomorpha, Current Biology (2023). DOI: 10.1016/j.cub.2023.07.003. www.cell.com/current-biology/f … 0960-9822(23)00908-9

Part 2

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Toothpaste containing synthetic tooth minerals can prevent cavities as effectively as fluoride: Clinical trial

Brushing twice a day keeps the dentist away—but can we improve on the toothpaste we use to maintain clean teeth, preventing medical issues that spiral from poor dental health? Most toothpastes use fluoride, a powerful tool for oral hygiene. However, fluoride can pose health problems in some cases, especially for children who consume too much fluoride by swallowing most of their toothpaste: children normally use only a tiny dose of toothpaste to avoid these problems, but that reduces toothbrushing efficacy.

In the search for alternatives, a team of international scientists and  clinicians have identified a hydroxyapatite toothpaste that works just as well as fluoride toothpaste to protect against cavities.

Hydroxyapatite is a safe and effective alternative to fluoride in caries prevention for daily use.

Hydroxyapatite is a calcium phosphate mineral found in the skeleton. It's known to be very safe for human consumption and has previously been shown to help with oral conditions like periodontitis. It can both inhibit the demineralization of teeth, a key step towards a cavity, and contribute to remineralization, which reinforces damaged tooth surfaces.

In a trial study  scientists found that nearly 90% of patients in both groups had no new cavities. There was no statistical difference in efficacy between the patients using a hydroxyapatite toothpaste and the control group using a fluoride tooth paste: both worked equally well.

Caries-preventing effect of a hydroxyapatite-toothpaste in adults: A 18 months double-blinded randomized clinical trial, Frontiers in Public Health (2023). DOI: 10.3389/fpubh.2023.1199728. www.frontiersin.org/articles/1 … bh.2023.1199728/full

Biology behind new drug used to treat triple-negative breast cancer uncovered

How TTP488 (azeliragon), an experimental drug, impairs aggressive, triple-negative breast cancer from metastasizing has been uncovered at the cellular level, according to researchers.

Triple-negative breast cancers (TNBCs) account for about 10–15% of all diagnosed breast cancers and are comprised of cancer cells that don't have estrogen or progesterone receptors, nor do they produce a protein called HER2 in significant quantities. TNBC's are more common in women younger than age 40 or those who are Black; for those cancers that metastasize, the five-year survival rate is only 12%. TNBCs have eluded effective treatment for decades. This discovery pinpoints some of the signaling pathways and cellular mechanisms through which a receptor that sits on the surface of TNBC cells, called the receptor for advanced glycation end-products (RAGE), regulates its deadly metastatic spread. Armed with this knowledge, the researchers were able to test the effectiveness of TTP488 in both the lab and in mice to show that the drug could be helpful in people.

Melinda Magna et al, RAGE inhibitor TTP488 (Azeliragon) suppresses metastasis in triple-negative breast cancer, npj Breast Cancer (2023). DOI: 10.1038/s41523-023-00564-9

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What is making 2023 likely the hottest year recorded

Human-made climate change is supercharging natural weather phenomena to drive heatwaves roasting Asia, Europe and North America that could make 2023 the hottest year since records began, scientists say.

Here experts explain how 2023 has got so hot, warning these record temperatures will get worse even if humanity sharply cuts its planet-warming gas emissions.

El Nino: After a record hot summer in 2022, this year the Pacific warming phenomenon known as El Nino has returned, heating up the oceans.

This may have provided some additional warmth to the North Atlantic, though because the El Nino event is only just beginning, this is likely only a small portion of the effect.

Scientists calculated that there was an 81-percent chance that 2023 would become the warmest year since thermometer records began in the mid-19th century.

Dust and sulphur: The warming of the Atlantic may also have been sharpened by a decrease of two substances that typically reflect sunlight away from the ocean: dust blowing off the Sahara desert and sulfur aerosols from shipping fuel.

Stagnant Anticyclones: Warming oceans affect land weather patterns, prompting heatwaves and droughts in some places and storms in others. The hotter atmosphere sucks up moisture and dumps it elsewhere.

Scientists highlighted the length and intensity of the lingering anticyclone systems bringing the heatwaves.

Where stagnant high-pressure areas persist over continents, the air sinks and warms, melting away clouds, causing intense summer sunshine to parch the soils, heating the ground and air above," with heatwaves "lodged in place" for weeks.

Climate change: 

Scientists at the Intergovernmental Panel on Climate Change (IPCC) said in their global summary report this year that climate change had made deadly heatwaves "more frequent and more intense across most land regions since the 1950s".

This month's heatwaves are "not one single phenomenon but several acting at the same time. But they are all strengthened by one factor: climate change.

Higher global temperatures make heatwaves longer and more intense. Despite being the main driver, climate change is one variable that humans can influence by reducing emissions from fossil fuels.

"We are moving out of the usual and well-known natural oscillations of the climate to unchartered and more extreme territory.

However, we have the ability to reduce our human influence on the climate and weather and to not create more extreme and long-lasting heatwaves.

The IPCC has said heatwaves risk getting more frequent and intense, though governments can limit climate change by reducing countries' greenhouse gas emissions.

Deep, rapid and sustained cuts in carbon emissions to net zero can halt the warming, but humanity will have to adapt to even more severe heatwaves in the future, Scientists warn.

Researchers Prove We Hear the Sound of Silence

Silence might not be deafening, but it's something that literally can be heard, concludes a team of philosophers and psychologists who used auditory illusions to reveal how moments of silence distort people's perception of time.

May I have your Attention please, this is very important. (And my AI is going to post this very frequently). The fights here are increasing global warming. Each of the activities you perform online comes with a small cost – a few grams of carbon dioxide are emitted due to the energy needed to run your devices and power the wireless networks you access. Less obvious, but perhaps even more energy intensive, are the data centres and vast servers needed to support the internet and store the content we access over it. Although the energy needed for a single internet search or email is small, approximately 4.1 billion people, or 53.6% of the global population, now use the internet. Those scraps of energy, and the associated greenhouse gases emitted with each online activity, can add up. The carbon footprint of our gadgets, the internet and the systems supporting them account for about 3.7% of global greenhouse emissions, according to expert estimates. If we were to rather crudely divide the 1.7 billion tonnes (1.6 billion tons) of greenhouse gas emissions estimated to be produced in the manufacture and running of digital technologies between all internet users around the world, it means each of us is responsible for 414kg (912lbs) of carbon dioxide a year. Internet users in some parts of the globe will have a disproportionately large footprint. If we were to rather crudely divide the 1.7 billion tonnes (1.6 billion tons) of greenhouse gas emissions estimated to be produced in the manufacture and running of digital technologies between all internet users around the world, it means each of us is responsible for 414kg (912lbs) of carbon dioxide a year. We can also alter the way we use our gadgets to cut our digital carbon footprints. It is okay if we use the net for the benefit of mankind. But for fighting? Over serial chars? This fighting is contributing to global warming. Now don't complain if the heat wave persists, if the crops fail, if your energy bill or food bill exceeds your budget capabilities. Girls, you yourself are responsible for it!

https://www.youtube.com/watch?v=qTySL9pHqUc&lc=UgzH8CLgVwRcrcUg...

Mammal mightier than the Dinos

An ancient fossil discovered in China shows a Cretaceous-period mammal preying on a dinosaur. The two animals were locked in combat when lava from a nearby volcanic eruption flowed over them, pristinely preserving the 125 million-year-old scene. The mammal, a Repenomamus roughly the size of an opossum, is clearly the aggressor as it bites into the ribs of a Psittacosaurus, a dinosaur nearly three times its size. 

Why this is cool: This is the first glimpse back in time of a mammal actively hunting a much larger dinosaur. “It’s like watching the coyote catch the roadrunner,” says Stephen Brusatte, a paleontologist at the University of Edinburgh. 

What the experts say: This mammal was something of an anomaly for its time—it would take tens of millions of years and an asteroid strike to give mammals the evolutionary advantage on Earth.

Mosquito-friendly gene drive may lead to a malaria-free future

Researchers have developed a gene drive solution for mitigating malaria transmission from mosquitoes.

In their paper, "Dual effector population modification gene-drive strains of the African malaria mosquitoes, Anopheles gambiae and Anopheles coluzzii," published in Proceedings of the National Academy of Sciences, they present a proposed gene drive approach to reducing human malaria cases by introducing genes into vector mosquitoes that hinder the transmission of the malaria parasite.

The study demonstrates the potential of using Cas9 guide RNA–based gene drive systems coupled with dual anti-parasite effector genes to rapidly spread through mosquito populations and reduce the load of Plasmodium falciparum, the parasite that causes malaria in humans.

Gene drives operate by taking advantage of genetic systems that link highly conserved or advantageous traits to chromosomes or other genetic elements with a positive transmission bias so that it will be inherited at rates much higher than 50%. In this way, a new gene can be introduced into a rapidly reproducing population with a small number of modified individuals and quickly spread to become dominant within the population.

Previous considerations of using gene drive modifications to eradicate mosquitoes have been met with great concern for the potential unintended effects of removing a species from the environment, even one as universally despised as mosquitoes.

Mosquitoes are food for many creatures, including several birds, bats, turtles, fish and frogs, spiders and snakes, dragonflies and damselflies. While they may have a taste for blood, mosquitoes primarily feed on nectar from small flowers, making them important pollinators.

The current study takes a much more holistic approach, essentially using the gene drive to vaccinate generations of mosquito populations against the parasite that causes malaria without harming the mosquitos or jeopardizing their important role in the ecosystem.

Researchers added the designed gene drive effector gene to a small population of mosquitoes under laboratory conditions. Trials were conducted using two strains of mosquitoes, Anopheles gambiae and Anopheles coluzzii. The genes were inherited by offspring at nearly 100%, and researchers observed the complete spread of the gene drive augmentation to captive wild-type populations within a few months. The effector genes spread by the gene drive produce monoclonal antibodies that target specific stages of the parasite's life cycle within the mosquitoes, significantly reducing P. falciparum prevalence and their potential subsequent infection intensity.

Transmission modeling predicts that, with a series of releases, the genetically modified mosquito strains could have swift and meaningful epidemiological impacts by reducing malaria incidence by 50% to 90% within just a few months.

Rebeca Carballar-Lejarazú et al, Dual effector population modification gene-drive strains of the African malaria mosquitoes, Anopheles gambiae and Anopheles coluzzii, Proceedings of the National Academy of Sciences (2023). DOI: 10.1073/pnas.2221118120

Two-faced star : Unusual white dwarf with a hydrogen side and a helium side

In a first for white dwarfs, the burnt-out cores of dead stars, astronomers have discovered that at least one member of this cosmic family is two faced. One side of the white dwarf is composed of hydrogen, while the other is made up of helium.

The surface of the white dwarf completely changes from one side to the other.

Part 1

Magnetic fields around cosmic bodies tend to be asymmetric, or stronger on one side. Magnetic fields can prevent the mixing of materials. So, if the magnetic field is stronger on one side, then that side would have less mixing and thus more hydrogen.

Another theory proposed by the scientists to explain the two faces also depends on magnetic fields. But in this scenario, the fields are thought to change the pressure and density of the atmospheric gases.

The magnetic fields may lead to lower gas pressures in the atmosphere, and this may allow a hydrogen 'ocean' to form where the magnetic fields are strongest.

At present scientists don't know which of these two theories is correct. so further work in this regard is being planned.

Ilaria Caiazzo, A rotating white dwarf shows different compositions on its opposite faces, Nature (2023). DOI: 10.1038/s41586-023-06171-9. www.nature.com/articles/s41586-023-06171-9

Part 2

Can two exoplanet siblings share a single orbit?

Using the Atacama Large Millimeter/submillimeter Array (ALMA), astronomers have found the possible "sibling" of a planet orbiting a distant star. The team has detected a cloud of debris that might be sharing this planet's orbit, which they think  could be the building blocks of a new planet or the remnants of one already formed. If confirmed, this discovery would be the strongest evidence yet that two exoplanets can share one orbit.

Two decades ago it was predicted in theory that pairs of planets of similar mass may share the same orbit around their star, the so-called Trojan or co-orbital planets. For the first time, scientists have found evidence in favour of that idea.

Trojans, rocky bodies in the same orbit as a planet, are common in our own solar system, the most famous example being the Trojan asteroids of Jupiter—more than 12,000 rocky bodies that are in the same orbit around the sun as the gas giant. Astronomers have predicted that Trojans, in particular Trojan planets, could also exist around a star other than our sun, but evidence for them is scant.

"Exotrojans [Trojan planets outside the solar system] have so far been like unicorns: They are allowed to exist by theory but no one has ever detected them.

Now, an international team of scientists have used ALMA, in which ESO is a partner, to find the strongest observational evidence yet that Trojan planets could exist—in the PDS 70 system. This young star is known to host two giant Jupiter-like planets, PDS 70b and PDS 70c. By analyzing archival ALMA observations of this system, the team spotted a cloud of debris at the location in PDS 70b's orbit where Trojans are expected to exist.

Trojans occupy the so-called Lagrangian zones, two extended regions in a planet's orbit where the combined gravitational pull of the star and the planet can trap material. Studying these two regions of PDS 70b's orbit, astronomers detected a faint signal from one of them, indicating that a cloud of debris with a mass up to roughly two times that of our moon might reside there.

The scientists think  this cloud of debris could point to an existing Trojan world in this system, or a planet in the process of forming.

O. Balsalobre-Ruza et al, Tentative co-orbital submillimeter emission within the Lagrangian region L5 of the protoplanet PDS 70 b, Astronomy & Astrophysics (2023). DOI: 10.1051/0004-6361/202346493

Bacterial protein found in the urogenital tract may contribute to reduced fertility, birth defects

A   study, published on July 17 in the Proceedings of the National Academy of Sciences (PNAS), established a new link between genomic instability and a protein from Mycoplasma fermentans, a kind of bacterium that commonly colonizes the urogenital tract. This bacterial protein also reduced fertility in mother mice and resulted in more birth defects in their newborn pups.

The study results not only broaden our understanding of the interplay between the urogenital tract microbiota and human reproductive health, but also shed light on the previously unidentified contribution of the human microbiota to genetic abnormalities.

For this latest study, researchers created mice that make the DnaK protein normally produced by the bacterium Mycoplasma fermentans. These mice with exposure to DnaK accrued genomic instability in which entire sections of the genome were duplicated or deleted, resulting in mice with varying numbers of copies of certain genes.

The team noticed that some of these mice from three to five weeks of age had problems with movement and coordination. They found that these mice have a deletion in the Grid2 gene, which in humans leads to the rare genetic disease known as spinocerebellar ataxia-18 (SCAR18) that causes delayed development of skilled movements and intellectual disabilities.

Remarkably, this instance marks the first time a mouse model successfully recapitulated a human genetic disease de novo, showcasing this model's potential for further cancer biology research.

More than a third of the female mice that made the DnaK protein were unable to get pregnant. Additionally, more than 20% of the pups born from moms with the DnaK protein had some sort of birth defect/deformity.

"The occurrences of genomic instability, in the form of increased number of copy number variations, could explain the decreased fertility and the increased instances of abnormally developed fetuses we observed upon DnaK exposure.

https://www.pnas.org/doi/10.1073/pnas.2219897120

Can India's new billion-dollar funding agency boost research?

The true cost of science’s language barrier
Researchers whose first language is not English can spend around twice as long reading an English-language scientific journal article as native speakers. In a survey of more than 900 environmental scientists from 8 countries, non-native speakers also reported needing more time to prepare conference presentations in English — and many avoid this type of commitment. Conservation scientist and co-author Tatsuya Amano has felt the impact first-hand as a Japanese researcher who has adapted to working in the United Kingdom and Australia. “Behind the scenes, I have to spend so much time to reach that level.”

https://journals.plos.org/plosbiology/article?id=10.1371/journal.pb...

https://www.nature.com/articles/d41586-023-02320-2?utm_source=Natur...

Lasting Brain Effects
Researchers recently examined the brains of patients born with congenital blindness who had their vision restored surgically. Despite many years of having their sight back, these individuals had a visual cortex that more closely resembled the corresponding visual areas of individuals with permanent blindness.

Why this matters: These findings suggest that harsh experiences or environments early in life can result in irreversible structural changes in multiple regions of the brain. Poverty and adversity (abuse or neglect) have often been found to have a widespread effect across the brain, and extrapolating from this vision study, experts expect permanent neurological changes resulting from harsh early experiences, write Cordula Hölig, Brigitte Röder and Ramesh Kekunnaya, cognitive neuroscientists and an ophthalmologist, respectively, who are the study’s lead authors.

What the experts say: “Poverty and adversity can cause changes in brain development. …Ensuring access to safe environments, affordable health care, healthy food and appropriate education gives children the opportunity to develop and stay physically and mentally healthy,” write the study authors.

People With Complete Color Blindness Given Their First Sight of Color
A small selection of volunteers who were completely color blind can now faintly detect a splash of color following retinal gene therapy.

Following the trial by researchers in Israel, three adults and one child who could only sense brightness of light found that after gene therapy they were able to tell a red object apart from its darker background.
Achromatopsia is caused by defects in genes that control cone cells, our eyes' color-sensors. The approximately 1 in 30,000 people affected see all the vibrant colors of the world as blurry shades of gray.

A single gene mutation caused the congenital condition in the volunteers, and the researchers hoped that inserting functional copies of the gene into cone cells would allow them to see color.
The researchers used a viral vector to transport a functional copy of the gene into the retina which houses cone cells, in one of each participant's eyes.
Researchers found treated 'achromats' can perceive red color, albeit in a very limited way, and differently than normally sighted controls.
But the different shades of gray were not replaced by a range of rainbow colors.

Nevertheless, color detection was evident in all patients' treated eyes.

https://www.cell.com/current-biology/fulltext/S0960-9822(23)00826-6?_returnURL=https%3A%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS0960982223008266%3Fshowall%3Dtrue

Study shows how the brain coordinates neuronal processing and communication during sleep

Past neuroscience studies have shown that while humans are sleeping, the brain remains highly active, consolidating memories and removing toxins accumulated during waking hours. While memory consolidation during sleep is a widely documented phenomenon, the processes underpinning it are yet to be fully elucidated.

Researchers recently carried out a study investigating the neural mechanisms through which the brain facilitates neuronal processing and communication between neurons during sleep. Their paper, published in Nature Neuroscience, unveils the processes through which the sequential unfolding of specific sleep rhythms coordinates memory consolidation while humans are asleep.

A few years ago, scientists found that some of the key sleep signatures ('slow oscillations,' 'spindles' and 'ripples') coincide in the hippocampus, the brain's 'memory hub.' This was a good indication that the synchronization of these sleep rhythms may be involved in memory consolidation. What was missing, however, was evidence that they in fact impact neuronal firing rates, i.e., the 'hard currency' of learning and plasticity.

Scientists now recorded the brain activity of 10 human participants as they were asleep using a technique known as intracranial electroencephalography (iEEG). These participants were patients with epilepsy who had electrodes implanted in their brain as part of their treatment.

While the patients were sleeping, Staresina and his colleagues simultaneously recorded their sleep rhythms and neuron firing rates. The recordings they collected showed that firing rates and neural communication are indeed orchestrated by slow oscillations, spindles and ripples, as they hypothesized.

Bernhard P. Staresina et al, How coupled slow oscillations, spindles and ripples coordinate neuronal processing and communication during human sleep, Nature Neuroscience (2023). DOI: 10.1038/s41593-023-01381-w

The First Dark Stars
At least three far-off objects observed by the James Webb Space Telescope (JWST) could be stellar objects called “dark stars.” These stars might not be fueled by nuclear fusion but by the self-annihilation of dark matter—the invisible stuff that is thought to make up about 85 percent of the matter in the universe. Dark stars could have formed soon after the big bang, from the collapse of helium and hydrogen clouds that annihilated the particles within.
Dark stars have never been definitively observed before–astronomers weren’t even sure they really existed. To prove these objects are indeed dark stars will take many months of observation–particularly, watching their electromagnetic spectrums for a particular isotope of helium only found in dark stars, not in galaxies.
“Finding a dark star would not only provide a new look into the early formation of the universe,” says Pearl Sandick, a theoretical particle physicist at the University of Utah, “but would also be a unique opportunity to directly observe dark matter interactions.
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In 2007, scientists proposed the idea of Dark Stars. The first phase of stellar evolution in the history of the universe may be Dark Stars (DS), powered by dark matter (DM) heating rather than by nuclear fusion. Although made almost entirely of hydrogen and helium from the Big Bang, they form at the centers of protogalaxies where there is a sufficient abundance of DM to serve as their heat source. They are very bright diffuse puffy objects and grow to be very massive. In fact, they can grow up to ten million solar masses with up to ten billion solar luminosities. In this paper, they show that the James Webb Space Telescope may have already discovered these objects.

https://www.pnas.org/doi/full/10.1073/pnas.2305762120

A Cracked Piece of Metal Healed Itself in an Experiment!

 Scientists observed a metal healing itself, something never seen before. If this process can be fully understood and controlled, we could be at the start of a whole new era of engineering.

researchers were testing the resilience of the metal, using a specialized transmission electron microscope technique to pull the ends of the metal 200 times every second. They then observed the self-healing at ultra-small scales in a 40-nanometer-thick piece of platinum suspended in a vacuum.

Cracks caused by the kind of strain described above are known as fatigue damage: repeated stress and motion that causes microscopic breaks, eventually causing machines or structures to break. Amazingly, after about 40 minutes of observation, the crack in the platinum started to fuse back together and mend itself before starting again in a different direction.

Researchers have now confirmed  that metals have their own intrinsic, natural ability to heal themselves, at least in the case of fatigue damage at the nanoscale.

These are exact conditions, and we don't know yet exactly how this is happening or how we can use it. However, if you think about the costs and effort required for repairing everything from bridges to engines to phones, there's no telling how much difference self-healing metals could make.

And while the observation is unprecedented, it's not wholly unexpected. In 2013, materials scientists  worked on a study predicting that this kind of nanocrack healing could happen, driven by the tiny crystalline grains inside metals essentially shifting their boundaries in response to stress.

That the automatic mending process happened at room temperature is another promising aspect of the research. Metal usually requires lots of heat to shift its form, but the experiment was carried out in a vacuum; it remains to be seen whether the same process will happen in conventional metals in a typical environment.

A possible explanation involves a process known as cold welding, which occurs under ambient temperatures whenever metal surfaces come close enough together for their respective atoms to tangle together. Typically, thin layers of air or contaminants interfere with the process; in environments like the vacuum of space, pure metals can be forced close enough together to literally stick.

https://www.nature.com/articles/s41586-023-06223-0

Caterpillar Conceals a Venom Unlike Any Ever Seen in Insects

Caterpillars with a notoriously painful sting may have evolved their venom with help from ancient microbes, according to a new study  by scientists.

Their analysis has uncovered signs that a process known as horizontal gene transfer may have allowed sequences for toxins to jump from bacteria to the insect some time in their evolutionary past.

While the caterpillar's venom remains largely shrouded in mystery, researchers say its molecular secrets could turn out to be surprisingly beneficial for us.

The caterpillars wielding this venom are larvae of flannel moths (Megalopyge sp.); a soft, fuzzy genus native to North and South America. They're sometimes called "puss caterpillars," since their luxuriant coats of hairlike bristles can make them look sort of like caterpillar-sized cats.

But that's not their only nickname. Also known as "asp caterpillars," there's a hidden danger below those bristles.

The caterpillars' fur obscures an arsenal of venomous spines, which can inject powerful toxins into any would-be predators or hapless humans who touch them.

This venom causes an immediate and intense burning pain, commonly inspiring descriptions such as "being hit with a baseball bat," "walking on hot coals," or "the worst pain a patient has ever experienced," the researchers write.

part 1

The quirks of asp caterpillar venom support the idea it evolved independently from other insect venom, the researchers say. In fact, its origins seem to lie outside the animal kingdom entirely.

When researchers  looked at it more closely, they saw proteins that were very similar to some of the bacterial toxins that make people sick.

Specifically, asp caterpillar venom resembles a type of bacterial toxin that binds itself to the surface of a cell, the researchers explain, assembling into doughnut-like structures that rip holes in their cell target.

While organisms normally pass genes down their offspring in a so-called vertical fashion, sometimes genes can be transferred across between species – even distantly related ones – in a less common horizontal process.

Previous research has found evidence of horizontal gene transfer from bacteria to other, more complex creatures, including the transfer of genes involved with producing venom toxins.

In their new study, researchers say they've found evidence that major components of asp caterpillar venom were recruited as venom toxins from genes that bacteria transferred horizontally to their ancestors.

The venom in these caterpillars has evolved via the transfer of genes from bacteria more than 400 million years ago.

https://www.pnas.org/doi/10.1073/pnas.2305871120

Part 2

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Scientists develop AI-based tracking and early-warning system for viral pandemics

 Research scientists have developed a machine-learning system—a type of artificial intelligence (AI) application—that can track the detailed evolution of epidemic viruses and predict the emergence of viral variants with important new properties.

In a paper published in Patterns on July 21, 2023, the scientists demonstrated the system by using data on recorded SARS-CoV-2 variants and COVID-19 mortality rates. They showed that the system could have predicted the emergence of new SARS-CoV-2 "variants of concern" (VOCs) ahead of their official designations by the World Health Organization (WHO). Their findings point to the possibility of using such a system in real-time to track future viral pandemics.

The software enabled the researchers to track sets of genetic changes appearing in SARS-CoV-2 variants around the world. These changes—typically trending towards increased spread rates and decreased mortality rates—signified the virus' adaptations to lockdowns, mask wearing, vaccines, increasing natural immunity in the global population, and the relentless competition among SARS-CoV-2 variants themselves.

One of the big lessons of this work is that it is important to take into account not just a few prominent variants, but also the tens of thousands of other undesignated variants, which the scientists  call the 'variant dark matter.

A similar system could be used to track the detailed evolution of future viral pandemics in real time, the researchers note. In principle, it would enable scientists to predict changes in a pandemic's trajectory—for example, big increases in infection rates—in time to adopt appropriate public health countermeasures.

William E. Balch, Understanding the Host-Pathogen Evolutionary Balance through Gaussian Process Modelling of SARS-CoV-2, Patterns (2023). DOI: 10.1016/j.patter.2023.100800. www.cell.com/patterns/fulltext … 2666-3899(23)00155-1

Using GPS as a possible earthquake predictor

A pair of seismologists  has found what might turn out to be an accurate way to predict earthquakes. In their study, reported in the journal Science, they looked at high-rate GPS time series data that was gathered in the time leading up to the moment earthquakes of magnitude 7 or above occurred. 

Seismologists have long sought to predict earthquakes so that people could react. In many cases, several minutes warning would be helpful—it would allow people to exit buildings that might collapse. Finding a precursor is difficult due to the lack of information regarding what was happening in the vicinity of an epicenter before a quake. In this new effort, they have found a way to go back in time to learn more about land shifting before a big quake.

In looking for an earthquake precursor, the researchers obtained and studied precise GPS data for geographical areas surrounding the epicenters of 90 quakes over magnitude 7 over the past several years. They found a pattern—a slip between tectonic plates that caused the land above them to move in a measurable, horizontal direction.

They also found that such slips could be observed and measured using GPS, that they occurred up to two hours before the earthquake struck and were too small to show up on standard seismographs. Most important, they saw the same slip in all the earthquakes they studied.

The work suggests that a reliable earthquake system could be designed based on a precise GPS listening system. On the downside,  researchers note that more work is required to prove that such a precursor exists for all, or at least most, large earthquakes. Also, they add, some upgrades to GPS technology are required to allow for measuring individual events around the clock.

 Quentin Bletery et al, The precursory phase of large earthquakes, Science (2023). DOI: 10.1126/science.adg2565

Roland Bürgmann, Reliable earthquake precursors?, Science (2023). DOI: 10.1126/science.adi8032

The role of ribosomes in the development of new treatments

The human body consists of trillions of cells, and 60% of the energy used within a cell is dedicated to a specific molecular machine. That machine is responsible for producing proteins, which are fundamental building blocks of the body.

The molecular machine is called a ribosome. The ribosome's task is to create proteins based on a copy of the genetic code found in the genome, known as mRNA. Until now, scientists thought that the ribosome performed the same type of work with all mRNA, like a standardized assembly line that it did not regulate on its own.

However, researchers now have discovered that this is not the case.

It has long been known that there are different types of ribosomes. But it has been assumed that no matter what mRNA you give the ribosome, it will produce a protein. But the new results suggest that different types of ribosomes produce specific proteins.

Scientists found that cancer cells have different ribosomes compared to other cells, and that was the basis for this new discovery. The paper based on this work is published in the journal Developmental Cell.

Part 1

This is an optical illusion.

The secret behind the confusing images is “reverse engineering”.

Devon, from 3D printing company Make Anything, proved that one side of each cylinder is shaped like a square and the other is more circular.

Very polite fish form queues in emergencies, new study finds

 Selfish humans push through one another to ensure their own survival – only to make everything worse. One very sensible species of fish forms queues to avoid exactly this issue, according to a new study.

When evacuating through narrow spaces, schools of neon tetra fish (Paracheirodon innesi) queue so that they don’t collide or clog up the line.

Researchers interpret this behaviour as respecting the social rules even in an emergency situation.  

Humans, like sheep, tend to quickly forget about social rules when they encounter a stressful situation, and rather adopt a selfish behaviour.

In the wild, neon tetra fish have to navigate around rocks in the rivers they swim along. To test how they do this when moving in large groups, a team of scientists from the University Grenoble Alpes, France, put the fish in a tank with narrow openings leading to other compartments.

These openings ranged in size from 1.5 to 4cm: not much bigger than the size of the fish themselves, which are 3cm long and 0.5cm wide.

The scientists then moved a fishing net through the tank and observed groups of 30 neon tetra fish as they evacuated through these openings.

The team were surprised to see that the fish gathered around the openings before passing through them – managing to avoid physical contact and clogging so that they could pass through at a constant rate.

The study marks the first time an experiment on crowd movements has focused on group evacuations in water. Previous observations have focused on animals that walk on 2D, solid surfaces.

https://www.nature.com/articles/s41598-023-36869-9?utm_medium=affil...

Deadly dust: Engineered stone is making workers sick

Workers making artificial-stone slabs for the most popular type of countertops  are developing a potentially deadly, irreversible lung disease from tiny particles of toxic dust, researchers found in the largest study of this emerging health crisis.

When the synthetic quartz is cut, ground and polished, lung-damaging dust is released into the air, leading to a disease called silicosis. The disease has plagued miners and cutters of natural stone for centuries, but the engineered stone is far more dangerous due to its high concentration of silica, a natural product in sandstone, and the harmful polymer resins and dyes that are added to the engineered product.

This growing occupational hazard has been sickening and claiming the lives of workers, predominantly young Latino men, at an alarming rate since the first U.S. silicosis case due to engineered stone was reported in 2015, according to the study published in the July 24, 2023, edition of JAMA Internal Medicine.

JAMA Internal Medicine (2023). jamanetwork.com/journals/jamai … ainternmed.2023.3295

The cost of being a non-native English speaker in science

English serves as a convenient, common language for science. However, this practice poses insurmountable barriers to those whose first language is not English—the majority of people around the world.

According to research published on July 18 in the open access journal PLOS Biology, the disadvantages of being a non-native English speaker in science range from difficulties in reading and writing papers to reduced participation in international conferences.

Few studies to date have quantified the manifold costs of being a non-native English speaker in science. Researchers surveyed 908 environmental scientists from eight countries with different linguistic and economic backgrounds, and compared the amount of effort required by individual researchers to conduct a variety of scientific activities in English.

The survey revealed clear and substantial disadvantages for non-native English speakers. Compared to native English speakers, non-native English speakers need up to twice as much time to read and write papers and prepare presentations in English. Papers written by non-native English speakers are 2.5 times more likely to be rejected and 12.5 times more likely to receive a request for revision, simply due to the written English. Many of them also give up attending and presenting at international conferences because they are not confident communicating in English.

These findings have important implications for global efforts to create a more inclusive academia where anyone can thrive and shine. The authors found that these disadvantages disproportionately affect those at an early career stage and from lower income countries. Unless we break down these barriers, the authors argue, we won't be able to achieve fair participation for non-native English speakers in science, nor can we expect contributions to science from those whose first language happens to be a language other than English.

The researchers point out that countless people must have given up their scientific careers because of language barriers.

The real, bigger picture issue is that we have done almost nothing as a community, and instead relied on individuals' own efforts to tackle this problem.

With this in mind, the paper also proposes potential solutions, which range from supervisors recognizing the difficulties faced by their students, to journals providing free English editing, and funders offering financial support to efforts working towards overcoming language barriers.

"To date, being fluent in English has been a ticket to enter the world of academia," according to these researchers. "We must abandon this old system. Anyone in any part of the world should be able to participate in science and contribute to accumulating humanity's knowledge", they conclude.

 Amano T, Ramírez-Castañeda V, Berdejo-Espinola V, Borokini I, Chowdhury S, Golivets M, et al. The manifold costs of being a non-native English speaker in science, PLoS Biology (2023). DOI: 10.1371/journal.pbio.3002184. journals.plos.org/plosbiology/ … journal.pbio.3002184

Psychological study suggests arithmetic is biologically-based and a natural consequence of our perception

Everyone knows that 2 + 2 = 4, but why do we have arithmetic in the first place, and why is it true?  have recently answered these questions by "reverse engineering" arithmetic from a psychological perspective. To do this, they considered all possible ways that quantities could be combined, and proved (for the first time in mathematical terms) that addition and multiplication are the simplest.

Their proof is based on four assumptions—principles of perceptual organization—that shape how we and other animals experience the world. These assumptions eliminate all possibilities except arithmetic, like how a sculptor's work reveals a statue hidden in a block of stone.

Monotonicity is the idea of "things changing in the same direction," and helps us keep track of our place in the world, so that when we approach an object it looms larger but smaller when we move away. Convexity is grounded in intuitions of betweenness. For example, the four corners of a football pitch define the playing field even without boundary lines connecting them. Continuity describes the smoothness with which objects seem to move in space and time. Isomorphism is the idea of sameness or analogy. It's what allows us to recognize that a cat is more similar to a dog than it is to a rock.

Taken together, these four principles structure our perception of the world so that our everyday experience is ordered and cognitively manageable.

The implications, explained in a paper in Psychological Review, are far-reaching because arithmetic is fundamental for mathematics and science. They suggest arithmetic is biologically-based and a natural consequence of our perception. Mathematics is thus a realization in symbols of the fundamental nature of the mind, and as such both invented and discovered. The seemingly magical success of mathematics in the physical sciences hints that our mind and the world are not separate, but part of a common unity.

Matt Grice et al, The psychological scaffolding of arithmetic., Psychological Review (2023). DOI: 10.1037/rev0000431

Dementia risk linked to protein imbalance
Abnormal levels of certain proteins — most of which have functions unrelated to the brain — could be an early hallmark of Alzheimer’s disease. In a decades-long study of more than 10,000 people, unbalanced levels of 32 proteins during middle age were strongly associated with an elevated chance of developing dementia in later life. Some of the proteins showed changes only in blood plasma but not in brain tissue, which suggests that “mechanisms below the neck could also play a role”, says neurologist Nicholas Seyfried.

https://www.science.org/doi/10.1126/scitranslmed.adf5681

Gloomy climate calculation: Scientists predict a collapse of the Atlantic ocean current to happen mid-century

Important ocean currents that redistribute heat, cold and precipitation between the tropics and the northernmost parts of the Atlantic region will shut down around the year 2060 if current greenhouse gas emissions persist. This is the conclusion based on new calculations from the scientists that contradict the latest report from the IPCC.

Contrary to what we may imagine about the impact of climate change in Europe, a colder future may be in store. In a new study, published in Nature Communications, researchers from the University of Copenhagen's Niels Bohr Institute and Department of Mathematical Sciences predict that the system of ocean currents which currently distributes cold and heat between the North Atlantic region and tropics will completely stop if we continue to emit the same levels of greenhouse gases as we do today.

Using advanced statistical tools and ocean temperature data from the last 150 years, the researchers calculated that the ocean current, known as the Thermohaline Circulation or the Atlantic Meridional Overturning Circulation (AMOC), will collapse—with 95% certainty—between 2025 and 2095. This will most likely occur in 34 years, in 2057, and could result in major challenges, particularly warming in the tropics and increased storminess in the North Atlantic region. "Shutting down the AMOC can have very serious consequences for Earth's climate, for example, by changing how heat and precipitation are distributed globally. While a cooling of Europe may seem less severe as the globe as a whole becomes warmer and heat waves occur more frequently, this shutdown will contribute to an increased warming of the tropics, where rising temperatures have already given rise to challenging living conditions.

"This result underscores the importance of reducing global greenhouse gas emissions as soon as possible," says the researchers.

The calculations contradict the message of the latest IPCC report, which, based on climate model simulations, considers an abrupt change in the thermohaline circulation very unlikely during this century.

Peter Ditlevsen, Warning of a forthcoming collapse of the Atlantic meridional overturning circulation, Nature Communications (2023). DOI: 10.1038/s41467-023-39810-w. www.nature.com/articles/s41467-023-39810-w

Egg 'signatures' allow drongos to identify cuckoo 'forgeries' almost every time, study finds

African cuckoos may have met their match with the fork-tailed drongo, which scientists predict can detect and reject cuckoo eggs from their nest on almost every occasion, despite them on average looking almost identical to drongo eggs.

Fork-tailed drongos, belligerent birds from sub-Saharan Africa, lay eggs with a staggering diversity of colors and patterns. All these colors and patterns are forged by the African cuckoo. Through natural selection, the African cuckoo's eggs have evolved to look almost-identical to drongo eggs—a rare example of high-fidelity mimicry in nature.

African cuckoos lay their eggs in drongos' nests to avoid rearing their chick themselves (an example of so-called brood parasitism). By forging drongo egg colors and patterns, cuckoos trick drongos into thinking the cuckoo egg is one of their own.

But drongos use knowledge of their own personal egg "signatures"—their eggs' color and pattern –to identify cuckoo egg "forgeries" and reject them from their nests, say scientists. These "signatures" are like the signatures we use in our daily lives: unique to each individual and highly repeatable by the same individual.

--- 

Researchers 

found that despite near-perfect mimicry of fork-tailed drongo eggs, African cuckoo eggs still have a high probability of being rejected.

Researchers carried out field work in the Choma district of Zambia during September to November across four years. The first step was to measure the differences in color and pattern of the fork-tailed drongo eggs and cuckoo eggs. The team found that the color and pattern of cuckoo eggs was, on average, almost identical to that of drongo eggs, and that all the broad types of drongo egg signatures were forged by the cuckoos.

The second step involved "egg rejection" experiments in which the researchers simulated cuckoo visits by "parasitizing" drongo nests with foreign eggs from other drongo nests (as a proxy for African cuckoo eggs). They then checked the nest daily to see whether the drongo parents accepted the foreign egg as one of their own, or realized it was an imposter and rejected it by removing it from their nest. The team could then test what differences in color and pattern between the foreign egg and the drongo's own eggs best predicted whether or not the drongo parents were tricked.

By combining results from both steps of the study, the researchers were able to create a model that predicted how often, on average, an African cuckoo would have its eggs rejected by a fork-tailed drongo host. They found the predicted rate of rejection to be 93.7%.

Additional simulations show this is likely due to drongos having evolved 'signatures' on their eggs. Even though cuckoos have evolved excellent 'forgeries,' individual cuckoos don't target individual drongo nests that match their own eggs. This means that for each cuckoo  egg laid, the likelihood that it will be a good enough match to that drongo's 'signature' is very low."

Lund et al. When perfection isn't enough: host egg signatures are an effective defence against high-fidelity African cuckoo mimicry, Proceedings of the Royal Society B: Biological Sciences (2023). DOI: 10.1098/rspb.2023.1125. royalsocietypublishing.org/doi … .1098/rspb.2023.1125

Link Between Vitamin D And Psoriasis Severity

Vitamin D deficiency or lower vitamin D levels are associated with a significant increase in the severity of psoriasis, according to new research on nearly 500 cases, one of the largest studies yet. These findings suggest people with the irritating skin condition that affects millions of people may benefit from vitamin D-rich foods or supplements. Psoriasis is an immune-mediated disease characterized by an abnormally fast turnover of skin cells, and its exact cause is unclear. It's thought to arise from a genetic predisposition triggered by environmental factors. Anyone who experiences its chronic buildup of dead cells, which causes itchy, scaly patches, knows psoriasis can be painful and involve more than just physical health. Some people even wrongly assume it's contagious. Scientists think vitamin D plays a role in preventing the progression of skin diseases by modulating the immune response and acting directly on the skin's repair cells. The researchers used self-reported psoriasis-affected body surface area to measure the severity of the disease in each individual. They also collected data on vitamin D levels from blood samples. After adjusting the data to account for lifestyle factors like age, gender, race, BMI, and smoking habits, the analysis found that people with lower vitamin D levels had significantly more severe psoriasis. Those with more psoriasis-affected body surface area had lower average vitamin D levels. On the other hand, the less affected someone's skin was by psoriasis, the higher their average vitamin D levels were. This relationship suggests that vitamin D might affect how psoriasis develops and progresses. Vitamin D deficiency has been previously linked with an increased risk of depression and COVID-19 mortality, while supplementation, when levels are inadequate, may reduce heart attack risk and ease depressive symptoms.

The study has been presented at the annual meeting of the American Society for Nutrition, NUTRITION 2023.

Man Tests Positive For MERS-CoV in Abu Dhabi, WHO Reports

A man has tested positive for MERS-CoV in Abu Dhabi, the WHO. So far, the 28-year-old is the only case to test positive out of 108 close contacts identified, but the WHO is urging vigilance.

MERS‐CoV is a coronavirus first identified in the Middle East in 2012 after the virus made its way into humans from bats via camels. It's one of a number of zoonotic viruses (those that jump from animals into people) that health authorities keep close tabs on. The WHO was notified of the confirmed case by the United Arab Emirates' health surveillance body on July 10, 17 days after the young man tested positive in hospital on June 23. In light of the case, WHO "re-emphasizes the importance of strong surveillance" for acute respiratory infections and has urged health authorities to "carefully review any unusual patterns."

"No secondary cases have been detected to date," WHO's July 24 statement reads, although the organization expects additional cases will be reported from the Middle East or other countries where the virus circulates in animal hosts.

According to the WHO, the man had not recently traveled outside of the UAE before his diagnosis on June 23, and has no known history of direct contact with dromedary camels, the usual source of MERS infections.

"WHO continues to monitor the epidemiological situation and conducts risk assessments based on the latest available information," the statement reads.

https://www.who.int/emergencies/disease-outbreak-news/item/2023-DON478

Meta-analysis finds vegetarian diets effective in lowering cholesterol, glucose and weight

Researchers have conducted a metadata analysis on vegetarian diets' effect on people at high risk of cardiovascular diseases (CVDs). They found that the vegetarian diet was associated with significantly improved LDL-cholesterol, HbA1c (glucose level) and body weight.

In their paper, "Vegetarian Dietary Patterns and Cardiometabolic Risk in People With or at High Risk of Cardiovascular Disease: A Systematic Review and Meta-analysis," published in JAMA Network Open, the researchers present a systematic review and meta-analysis of randomized clinical trials (RCTs) on vegetarian diets' effects in individuals with or at high risk of CVDs. It aimed to assess the association of vegetarian diets with outcomes, including LDL-C, HbA1c, SBP, body weight and energy intake.

In analyzing the data from 29 studies on 20 randomized clinical trials over 22 years with 1,878 total participants, the researchers found consistently positive outcomes for participants on vegetarian diets. The studies used were mainly conducted in the U.S. and also included studies from the Czech Republic, Italy, Iran, Korea, New Zealand, and the Republic of China. Within the metadata were subsets of study parameters that all followed a similar result trend. Compared with participants' usual diet, vegetarian intervention diets significantly lowered LDL-C by 12.9 mg/dL. Compared with external control diets, consuming a vegetarian diet was associated with decreased LDL-C by 6.6 mg/dL in a mean of six months.

Vegetarian diets were associated with similar LDL-C reduction in studies with (−7.2 mg/dL) and without (−6.8 mg/dL) energy restriction involved. Vegetarian diets even lowered LDL-C (−5.9 mg/dL) in a subset of studies with no physical activity intervention or requirements.

The most consistent weight reduction was observed in people at high risk of CVDs (−9.1 mg/dL). Among all different vegetarian diets, lacto-ovo (including dairy and egg) vegetarian diets were associated with the greatest reduction in LDL-C.

The most significant weight reduction was observed in people at high risk of CVD (−3.6), followed by people with type 2 diabetes (−2.8 kg). An unexpected signal between restricted and unrestricted caloric studies observed more than twice the weight reduction in vegetarian intervention diets without energy restriction.

Those with unrestricted (vegetarian) calorie intake lost an average of 4.7 kg compared to 1.8 kg for those with energy-restricted vegetarian diets. It is unclear if this indicates additional benefits of an all-you-can-eat vegetarian diet, specific limitations on the type of foods available, or hidden high-calorie deviations from participants on restrictive diets.

Part 1

However, not all vegetarian diets are alike

Vegetarian meals marketed for convenience may be high in calories, refined carbohydrates, hydrogenated oils, high-fructose corn syrup, sucrose or artificial sweeteners and salt.

A higher risk of CVD and diabetes is possible on a vegetarian diet if the veggies pass through a deep fryer first. Foods rich in trans fatty acids and salt are associated with a 32% higher risk of coronary heart disease and a high risk of type 2 diabetes.

While a meta-analysis of 20 past trials cannot control for the wide range of diets included in those studies, which ranged from vegan to vegetarian (allowing for eggs and dairy), the overall signal from these diverse vegetarian diets was clear.

The vegetarian diet is associated with significant improvements in LDL-C, HbA1c (glucose level) and body weight in individuals with type 2 diabetes or at high risk of CVDs.

The data suggests that vegetarian diets might have a synergistic (or at least nonantagonistic) use in potentiating the effects of optimal drug therapy in the prevention and treatment of a range of cardiometabolic diseases.

So these things must be understood properly before going for a vegetarian diet.

Tian Wang et al, Vegetarian Dietary Patterns and Cardiometabolic Risk in People With or at High Risk of Cardiovascular Disease, JAMA Network Open (2023). DOI: 10.1001/jamanetworkopen.2023.25658

Part 2

Long Hot July
Science articles have had their own recurring theme in recent weeks: extreme heat. An expert recently said,  “I’m feeling like a broken record about heat breaking records.” As if to further her point, today she gathered a list of the latest all-time high temps–ALL set in 2023. To cap it off, this July is set to be the hottest month ever recorded on Earth—and likely the hottest in about 120,000 years—preliminary analyses show.

What's causing this: Breaking high-temperature records is a hallmark of climate change. With more and more heat being trapped in the atmosphere by the greenhouse gases emitted when humans burn fossil fuels, heat records are now set increasingly more often than cold ones.

The solution is to ditch fossil fuels as soon as possible and to build up our use of renewable energy. Easier said than done, yes, but if extreme weather is the sweltering, flooding, hurricaning canary in the coal mine we know it to be, the urgency to make change is ramping up.

Then follow all that experts say. 

Scientists discover secret of virgin birth, and switch on the ability in female flies

For the first time, scientists have managed to induce virgin birth in an animal that usually reproduces sexually: the fruit fly Drosophila melanogaster.

Once induced in this fruit fly, this ability is passed on through the generations: The offspring can reproduce either sexually if there are males around, or by virgin birth if there aren't.

For most animals, reproduction is sexual—it involves a female's egg being fertilized by a male's sperm. Virgin birth, or "parthenogenesis," is the process by which an egg develops into an embryo without fertilization by sperm—a male is not needed. The offspring of a virgin birth are not exact clones of their mother but are genetically very similar, and are always female.

This work 's the first to show that you can engineer virgin births to happen in an animal—it was very exciting to see a virgin fly produce an embryo able to develop to adulthood, and then repeat the process.

In the genetically manipulated flies, the females waited to find a male for half their lives—about 40 days—but then gave up and proceeded to have a virgin birth.

In the experiments, only 1–2% of the second generation of female flies with the ability for virgin birth produced offspring, and this occurred only when there were no male flies around. When males were available, the females mated and reproduced in the normal way.

Switching to a virgin birth can be a survival strategy: A one-off generation of virgin births can help to keep the species going.

To achieve their results, researchers first sequenced the genomes of two strains of another species of fruit fly, called Drosophila mercatorum. One strain needs males to reproduce, the other reproduces only through virgin birth. The researchers identified the genes that were switched on or switched off when the flies were reproducing without fathers.

With the candidate genes for virgin birth ability identified in Drosophila mercatorum, the researchers altered what they thought were the corresponding genes in the model fruit fly, Drosophila melanogaster. It worked: Drosophila melanogaster suddenly acquired the ability for virgin birth.

The research involved over 220,000 virgin fruit flies and took six years to complete.

More information: Alexis L Sperling, A genetic basis for facultative parthenogenesis in Drosophila, Current Biology (2023). DOI: 10.1016/j.cub.2023.07.006. www.cell.com/current-biology/f … 0960-9822(23)00913-2

How a gut microbe causes flies to live fast and die young

Researchers have uncovered how one species of gut bacteria causes fruit flies to perish early. This discovery illuminates the complex interactions between the microbes in our guts and our health.

The human gut is home to somewhere between 200 and 1,000 species of bacteria. The vast majority of these species are beneficial, converting food into useful compounds that the human body cannot make by itself. But some bacterial species have a negative impact on health.

The sheer number of bacterial species in the human gut makes it extremely challenging to untangle their individual effects on our health. Researchers find it much simpler to look at the gut microbiome of fruit flies since they only have about two to five bacterial species in their guts.

In a previous study, researchers have found that one of these species, Acetobacter persici, accelerated aging in flies, causing them to die early. A. persici has a drastic impact on fly lifespan, curtailing it by about 20%–30%.

Now, by feeding flies with a diet of dead A. persici, scientists have discovered the connection between A. persici and shortened fly lifespans.

To their surprise, the researchers found that the shortened lifespan is not due to a compound produced by A. persici. Rather, a component in the bacterium's cell wall triggers a receptor in the fly's gut, which stimulates the immune system, boosting the production of antimicrobial compounds and activating intestinal stem cells. It's this enhanced immunity that causes the flies to die young. In an intriguing twist, the team discovered that these effects also boost a fly's resistance to infection by a harmful bacterium that can kill flies. It thus provides flies with a short-term advantage in exchange for an early death—a tradeoff that the researchers dubbed a "live fast, die young" lifestyle.

This increased resistance to infection explains why the vast majority of flies in the wild have A. persici or other Acetobacter species in their guts. It's better to have a strong resistance to stressors such as infection rather than to live to a ripe old age.

The finding raises the possibility that "postbiotics"—food and drinks that contain dead gut microbes (rather than prebiotics containing live ones)—with health benefits could be developed.

The team now aims to determine the genes involved in the immune signaling that leads to shorter lifespans. They also want to see if the same mechanism occurs in other animals such as mice and humans.

Taro Onuma et al, Recognition of commensal bacterial peptidoglycans defines Drosophila gut homeostasis and lifespan, PLOS Genetics (2023). DOI: 10.1371/journal.pgen.1010709

Microorganisms ward off parasites: Potential new function of CRISPR-Cas system discovered

Microorganisms use the CRISPR-Cas system to fight viral attacks. In genetic engineering, the microbial immune system is used for the targeted modification of the genetic make-up. A research team has now discovered another function of this specialized genomic sequence: archaea—microorganisms that are often very similar to bacteria in appearance—also use them to fight parasites. 

They analyzed the genetic material of microbes in the Earth's deep crust. More than 70% of the Earth's microorganisms are housed in the deep biosphere. If we want to understand diversity on our planet, it is worth taking a look into the deep.

The microbiologists have analyzed the water that a geyser in the U.S. spits to the surface from the depths, as well as samples from the Horonobe underground laboratory in Japan. The research team focused on archaea, which live in the ecosystem as hosts and parasites. The tiny microbes are highly similar to bacteria in cell size but have substantially different physiological properties. The result of their genomic analysis provided new insights: there were conspicuously few parasites in the vicinity of the hosts, and the hosts showed genetic resistance to the parasites. The researchers discovered the reason for this in the genetic scissors in the genome of the microorganisms.

In the course of evolution, the archaea have incorporated the parasitic DNA. If a parasite with the same DNA now attacks the organism, the foreign genetic material is probably recognized by the CRISPR system and presumably decomposed.

In order to rule out the possibility that they have only come across isolated cases, the researchers have extended the analysis to more than 7,000 genomes and observed the phenomenon very frequently.

Sarah P. Esser et al, A predicted CRISPR-mediated symbiosis between uncultivated archaea, Nature Microbiology (2023). DOI: 10.1038/s41564-023-01439-2

Researchers discover how mitochondria call for help when under stress

As life propagated across Earth in the form of the widest variety of single-celled organisms, sometime between 3.5 and 1 billion years ago one such organism managed an evolutionary coup: Instead of devouring and digesting bacteria, it encapsulated its prey and used it as a source of energy. As a host cell, it offered protection and nutrition in return.

This is referred to as the endosymbiotic theory, according to which that one single-celled organism was the primordial mother of all higher cells, out of which all animals, fungi and plants developed. Over the course of billions of years, the encapsulated bacterium became the cell's powerhouse, the mitochondrion, which supplies it with the cellular energy currency ATP.

It lost a large part of its genetic material—its DNA—and exchanged smaller DNA segments with the mother cell. However, now as in the past, mitochondria divide independently of the cell and possess some genes of their own.

How closely the cell and the mitochondrion work together in human cells today is what some researchers are investigating. They have now discovered how the mitochondrion calls for help from the cell when it is under stress. Triggers for such stress can be infections, inflammatory diseases or genetic disorders, for example, but also nutrient deficiencies or cell toxins. The study has been published in the journal Nature.

A certain type of mitochondrial stress is caused by misfolded proteins that are not quickly degraded and accumulate in the mitochondrion. The consequences for both the mitochondrion and the cell are dramatic: Misfolded proteins can, for example, disrupt energy production or lead to the formation of larger amounts of reactive oxygen compounds, which attack the mitochondrial DNA and generate further misfolded proteins. In addition, misfolded proteins can destabilize the mitochondrial membranes, releasing signal substances from the mitochondrion that activate apoptosis, the cell's self-destruction program. The mitochondrion responds to the stress by producing more chaperones (folding assistants) to fold the proteins in order to reduce the misfolding, as well as protein shredding units that degrade the misfolded proteins. Until now, how cells trigger this protective mechanism was unknown.

The researchers artificially triggered misfolding stress in the mitochondria of cultured human cells and analyzed the result. What makes it difficult to unravel such signaling processes is that an incredibly large number take place simultaneously and at high speed in the cell.

The research team therefore availed itself of methods (transcriptome analyses) that can be used to measure over time to what extent genes are transcribed. In addition, the researchers observed, among other things, which proteins bind to each other at which point in time, at which intervals the concentrations of intracellular substances change, and what effects there are when individual proteins are systematically deactivated.

Part 1

The result is that the mitochondria send two chemical signals to the cell when protein misfolding stress occurs: They release reactive oxygen compounds and block the import of protein precursors, which are produced in the cell and are only folded into their functional shape inside the mitochondrion, causing these precursors to accumulate in the cell. Among other things, the reactive oxygen compounds lead to chemical changes in a protein called DNAJA1. Normally, DNAJA1 supports a specific chaperone (folding assistant) in the cell, which molds the cell's newly formed proteins into the correct shape.

As a consequence of the chemical change, DNAJA1 now increasingly forces itself on the folding assistant HSP70 as its helper. HSP70 then takes special care of the misfolded protein precursors that accumulate around the mitochondrion because of the blocked protein import. By doing so, HSP70 reduces its interaction with its regular partner HSF1. HSF1 is now released and can migrate into the cell nucleus, where it can trigger the anti-stress mechanism for the mitochondrion.

It was very exciting to discover how the two mitochondrial stress signals are combined into one signal in the cell, which then triggers the cell's response to mitochondrial stress. Moreover, in this complex process, which is essentially driven by tiny local changes in concentration, the stress signaling pathways of the cell and the mitochondrion dovetail very elegantly with each other—like the cogs in a clockwork.

F. X. Reymond Sutandy et al, A cytosolic surveillance mechanism activates the mitochondrial UPR, Nature (2023). DOI: 10.1038/s41586-023-06142-0

Part 2

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Who are scientists on whom experiments were performed?

Here is the story of a Doctor Who Jammed a Catheter Into His Heart to help humanity…

Werner Theodor Otto Forßmann : (29 August 1904 – 1 June 1979) was a German researcher and physician from Germany who shared the 1956 Nobel Prize in Medicine (with Andre Frederic Cournand and Dickinson W. Richards) for developing a procedure that allowed cardiac catheterization. In 1929, he put himself under local anesthesia and inserted a catheter into a vein of his arm. Not knowing if the catheter might pierce a vein, he put his life at risk. Forssmann was nevertheless successful; he safely passed the catheter into his heart.

Twinkle twinkle little star
What if you can 'listen' to that twinkle?
Wouldn’t that be wonderful?
Yes, you can, now!
Science makes it possible

Imagine the melodies of distant worlds!
Click on the video below to listen to the twinkle of a star

And clap like a child

Nerve cells in the brain can halt all movement in the body—even breathing

When a hunting dog picks up the scent of a deer, it sometimes freezes. On the spot. The same thing can happen to people who need to concentrate on a challenging task.

Now researchers have made a discovery that adds to our knowledge of what happens in the brain when we suddenly stop moving. They have found a group of nerve cells in the midbrain which, when stimulated, stop all movement. Not just walking; all forms of motor activity. They even make the mice stop breathing or breathe more slowly, and the heart rate slow down.

There are various ways to stop movement. What is so special about these nerve cells is that once activated they cause the the movement to be paused or freeze. Just like setting a film on pause. The actors movement suddenly stop on the spot.

When the researchers ended activating the nerve cells, the mice would start the movement exactly where it stopped. Just like when pressing "play" again.

This 'pause-and-play pattern' is very unique; it is unlike anything we have seen before. It does not resemble other forms of movement or motor arrest we or other researchers have studied. There, the movement does not necessarily start where it stopped, but may start over with a new pattern.

The nerve cells stimulated by the researchers are found in the midbrain in an area called the pedunculopontine nucleus (PPN), and they differ from other nerve cells there by expressing a specific molecular marker called Chx10. The PPN is common to all vertebrates including humans. So even though the study was performed in mice, the researchers expect the phenomenon to apply to humans too.

Part 1

Some might suggest that the nerve cells are activated by fear. Most people are familiar with the phenomenon of "freezing" caused by extreme fear. But that is not the case.

Researchers  have compared this type of motor arrest to motor arrest or freezing caused by fear, and they are not identical. They are very sure that the movement arrest observe here is not related to fear. Instead, they think  it has something to do with attention or alertness, which is seen in certain situations.

The researchers think it is an expression of a focused attention. However, they stress that the study has not revealed if this is indeed the case. It is something that requires more research to demonstrate.

The new study may be able to help us understand some of the mechanisms of Parkinson's disease.

Motor arrest or slow movement is one of the cardinal symptoms of Parkinson's disease. Scientists speculate that these special nerve cells in PPN are over-activated in Parkinson's disease. That would inhibit movement. Therefore, the study, which primarily has focused on the fundamental mechanisms that control movement in the nervous system, may eventually help us to understand the cause of some of the motor symptoms in Parkinson's disease.

Among other things, the researchers used optogenetics to stimulate the nerve cells in the brainstem.

In short, optogenetics is a biological technique that involves genetically modifying specific brain cells to make them more sensitive to light. This means that the cells can be activated by a flash of light.

In the study, the researchers were able to stimulate the specific group of nerve cells  in mice and thus determine the motor function of these cells.

New study links brain waves directly to memory

Neurons produce rhythmic patterns of electrical activity in the brain. One of the unsettled questions in the field of neuroscience is what primarily drives these rhythmic signals, called oscillations. Researchers have found that simply remembering events can trigger them, even more so than when people are experiencing the actual event.

The researchers, whose findings are published in the journal Neuron, specifically focused on what are known as theta oscillations, which emerge in the brain's hippocampus region during activities like exploration, navigation and sleep. The hippocampus plays a crucial role in the brain's ability to remember the past. Prior to this study, it was thought that the external environment played a more important role in driving theta oscillations. But this new study found that memory generated in the brain is the main driver of theta activity.

They found that theta oscillations in humans are more prevalent when someone is just remembering things, compared to experiencing events directly.

The results of the study could have implications for treating patients with brain damage and cognitive impairments, including patients who have experienced seizures, stroke and Parkinson's disease. Memory could be used to create stimulations from within the brain and drive theta oscillations, which could potentially lead to improvements in memory over time.

Sarah E. Seger et al, Memory-related processing is the primary driver of human hippocampal theta oscillations, Neuron (2023). DOI: 10.1016/j.neuron.2023.06.015