Scientists release updated primate evolutionary lineage

Posted on December 18, 2024 by Igor Mitreski

Primates, consisting of apes, monkeys, tarsiers, and lemurs, are among the most charismatic and well-studied animals on Earth.

Phylogeny of 455 primates synthesized using Chrono-STA. The roots of the phylogeny were discovered 71.3 million years ago. The crown of Strepsirrhini is 57 million years old, and the crown of Haplorrhini is 68.5 million years old. The crown of the eyelid is 42.2 million years old. Image credit: Craig others., doi: 10.3389/fbinf.2024.1495417.

Primate mammals consist of 172 species of Old World apes and monkeys (Cataluni), 146 species of New World monkeys (Platyria), and 144 species of lemurs, lorises, and galagos (Strepsilini).

Primates exhibit some of the most remarkable behaviors observed in nature. Chimpanzees use specially chosen sticks to “fish” for termites inside hollow logs, while orangutans use leaves as gloves to handle the prickly durian fruit.

Although they are some of the most intensely studied species on Earth, there is no comprehensive molecular phylogenetic hypothesis about the evolutionary history of primates that summarizes the patterns and timing of relationships among all primates. plug.

Such phylogenetic trees use molecular sequence data to tell us both when each species or group of species first appeared and which other groups on the tree are their closest relatives. Masu.

The largest timed molecular phylogenetic tree, called the “Time Tree,” includes just over 200 primate species to date, but the largest synthetic time tree, based on more than 4,000 published studies, , containing only twice that number, and about one-fifth of the primates remaining. The tree of life is unresolved.

“The value of a timed evolutionary tree that includes all species of a particular lineage cannot be underestimated,” said lead author Dr. Jack Craig and colleagues at Temple University.

“These trees are inherently fascinating because they capture the evolutionary history that has given us our current biodiversity, but they also form an essential foundation for many types of future research. I will.”

“For example, taxonomic and systematic efforts to catalog species rely on them to identify new lineages.”

“The study of the rate of evolution and its possible correlations, such as climate and geological changes, is fundamentally tied to its underlying phylogeny.”

“Disciplines such as biogeography, phylogeography, and historical ecology, which use time trees to investigate spatial and ecological patterns, would not be possible without phylogeny.”

“And as we watch global biodiversity being lost in ongoing extinction events, phylogenetics can help identify conservation priorities and help save species. It is an essential tool in assessing the impact of our efforts.”

In the new study, the authors were able to construct a time tree of 455 primates, incorporating all species for which molecular data are available.
This phylogenetic tree is the most complete description of the evolutionary relationships among primates to date.

“This effort proves that while the evolutionary history of even some of the most charismatic species on Earth is incompletely understood, we have the tools to fill many of the knowledge gaps. “We did so,” the researchers said.

“We believe our research protocol will be an accessible and ultimately extremely valuable tool in the effort to understand evolution.”

“We have found that complete time trees are a fundamental resource in many fields and can often be constructed from existing data.”

“Furthermore, such a complete time tree allows us to test hypotheses that would otherwise not be possible.”

“For example, our study shows that the number of species in different primate clades is better explained by unique rates of speciation, with some primate lineages generating new species much faster than others. Or whether the best explanation is simply time: all lineages produce new species at about the same rate, and older lineages produce more species over time.''

“What we discovered is that the major groups of primates actually all share relatively similar speciation rates, and therefore their age is a better predictor of species richness. That's what it means.

“This analysis becomes very problematic when a time tree is missing many species or dates, so it serves as a perfect example of the usefulness of large, complete time trees.”

of the team result appear in the diary Frontiers of bioinformatics.

_____
Jack M. Craig others. 2024. Completed primate molecular time tree. Frontiers of bioinformatics 4;doi: 10.3389/fbinf.2024.1495417

Source: www.sci.news

Improving Nature, Climate, and Health Simultaneously through a Unified Approach

Posted on December 17, 2024 by Igor Mitreski

Tree-planting projects help tackle the climate crisis, but they can also impact water supplies

Cost Photo/NurPhoto

The major environmental, social and economic crises facing the world today, including biodiversity, climate change, health, food, and water, are closely linked, and we must work together to tackle them. has many advantages. However, focusing on just one issue can exacerbate other crises.

This is the conclusion of a major report compiled by 165 researchers from 57 countries and approved by 147 governments over the past three years.

United Nations conventions on issues such as biodiversity and climate focus on these issues separately. “So what we will do now in this report, which has not been done before, is to combine all of these and make sure that looking at these crises individually is not only inefficient, but actually the real danger. “It's about showing what's involved,” he says. paula harrison He co-chaired the evaluation process for the report at the UK Center for Ecology and Hydrology. “Action is urgent, but unless we act in a way that takes these interdependencies into account, we will create new problems or exacerbate existing ones.”

Mr Harrison said the scientific studies assessed for this report provide strong evidence that there are a number of actionable actions that can have beneficial effects on all five areas simultaneously. . These include conserving and restoring mangrove forests, improving soil health and carbon content, creating early warning systems for all kinds of hazards, reducing the risk of disease spread from animals to humans, and universal health insurance. It includes international cooperation on technology related to the problem.

There is a trade-off. Actions that have broad benefits are not the same as actions that are the best solution to a particular problem, she says.

“What you can’t do is get the best value possible at the same time,” Harrison says. “While we cannot optimize food production without negatively impacting everything else, we can take a balanced approach that benefits all.”

Harrison gives the example of planting trees to remove carbon dioxide from the atmosphere. If the focus is solely on climate, the trees selected are likely to be fast-growing non-native species that do not support wildlife and affect water supplies by taking up too much water. However, if a project takes a more holistic approach, it may choose native tree species that use less water and increase biodiversity. “It may not sequester as much carbon, but it will add a lot of value to other aspects of the system,” Harrison says.

There are also economic benefits to integrated approaches that help conserve biodiversity and achieve other goals. nexus reportMore than half of the world's gross domestic product ($50 trillion), as it is officially known, states that it is moderately to highly dependent on nature.

“The unaccounted costs of our current approach to economic activity, including climate change impacts on biodiversity, water, health, and food production, are estimated to be at least $10 trillion to $25 trillion per year. It has been.” Pamela McElwee The other co-chair, a professor at Rutgers University in New Jersey, said in a statement.

“There is a lot of evidence that there are very strong and growing biophysical risks to economic prosperity and financial stability if we continue the way we are,” Harrison said.

The Nexus report was compiled by: Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES)which is a non-UN body, but functions in a similar way to the Intergovernmental Panel on Climate Change. The report was formally approved by representatives of the 147 IPBES member countries who met in Namibia on 16 December.

says the report is very ambitious Anne LarigoderlyExecutive Director of IPBES. Its purpose is to provide the science and evidence needed to support the achievement of other international conventions, such as the United Nations Sustainable Development Goals, the Kunming-Montreal Global Biodiversity Framework, and the Paris Agreement on climate change. , she says.

Source: www.newscientist.com

Electronic tongue accurately identifies chemical makeup of alcoholic beverages

Posted on December 17, 2024 by Igor Mitreski

Molecular tests can be used to assess the quality of drinks

Evgeny Parilov/Alamy

Beverage manufacturers and consumers may soon have access to small, portable kits not unlike coronavirus tests to check the quality and safety of alcoholic beverages.

The device is called an “artificial tongue” because it can detect additives, toxins, and sweetness in drinks with just a few drops.

Shuo Fan Researchers at China’s Nanjing University say this first-generation new technology cannot yet test for date rape drugs or detect methanol contamination in spiked drinks. A recent incident occurred in Laos in which six backpackers were killed.In future versions,

Current methods for analyzing alcoholic beverages, such as liquid chromatography, require expensive and cumbersome laboratory equipment and require specialized technicians to manipulate and analyze the samples.

The artificial tongue relies on biological nanopore technology. It uses modified organisms, such as bacteria, that have tiny holes, or pores, in their cell membranes that are just a few nanometers in diameter. By charging the membrane with an electrical charge, small molecules of the substance being tested can be drawn into the pores and passed through them.

When these molecules pass through the nanopore, they generate unique electrical signatures that can be analyzed to identify the chemicals present in the sample. Nanopores have already revolutionized DNA sequencing, allowing genetic material to be tested almost instantly using easily portable equipment.

Huang and colleagues used nanopores made in bacteria, called micropores, that have already been introduced for DNA sequencing. Smegmatis bacterium.

The device uses artificial intelligence to identify molecules that pass through the nanopores, such as fragrance compounds and additives, Huang said. “The sensor tells you right away what type of alcoholic beverage it is,” he says. “It can provide a quantitative standard of the product and also easily identify counterfeit alcoholic beverage products.”

Nanopore detectors require only a power source to operate, he says. “This nanopore sensing assay can be performed at home, in the office, or on the street as easily as a COVID-19 test,” Huang said. “You just add a drop of alcoholic beverage to the sensor and wait for the results. The machine learning algorithm does the rest of the work.”

topic:

biotechnology /
Eating and drinking

Source: www.newscientist.com

New fossil discovery suggests that Therapsids originated in the tropics, not temperate regions

Posted on December 17, 2024 by Igor Mitreski

Paleontologists have discovered a new species of early gorgonopsian therapsid that was part of the ancient summer humid biome of equatorial Pangea.

Recreating the life of the Gorgonopsians of Mallorca in a floodplain environment. Image credit: Henry Sutherland Sharpe.

Therapsids were a major component of Permian terrestrial ecosystems around the world, eventually giving rise to mammals in the early Mesozoic Era.

However, little is currently known about when and where it originated.

“Therapsids are a diverse and ecologically successful clade of tetrapods, of which the modern representatives are mammals,” says paleontologist at the Museum of Science and Nature in Barea and the Paleontological Institute of Catalonia. said Dr. Rafel Matamares and colleagues.

“The roots of this clade date back to the late Paleozoic era, when non-mammalian therapsids were important components of terrestrial ecosystems.”

“The oldest distinct therapsids known to date were Laranimus dashankoensisprobably from the Rhodian (Late Middle Permian) deposits of Central East Asia.

“However, phylogenetic analyzes consistently show that therapsids are a sister group to the pterosaur ‘perisaurian’ class monoapsids, which originated in Pennsylvania (about 320 million years ago). It suggests that

“This implies a long lineage of therapsid ghosts spanning about 40 million years.”

The newly discovered therapsid is the oldest of its kind, and possibly the oldest therapsid ever discovered.

This dog-like saber-toothed animal does not yet have a species name, but it belongs to a group of therapsids called gorgonopsids.

“Gorgonopsids are more closely related to mammals than to other modern animals,” said Dr. Ken Angielczyk, a paleontologist at the Field Museum.

“They have no modern descendants and are not our direct ancestors, but they are related to species that were our direct ancestors.”

“The oldest known gorgonopsids lived about 265 million years ago, but the newer fossils date from 270 to 280 million years ago.”

“This is probably the oldest chrysophyte on Earth,” said Dr. Josep Fortuny, a paleontologist at the Miquel Crusafont Catalan Institute of Paleontology.

This fossil was discovered on the Spanish island of Mallorca in the Mediterranean Sea. However, during the time of the Gorgonopsians, Mallorca was part of the supercontinent Pangea.

“The amount of bone remains is surprising,” Dr. Matamares said.

“We found everything from fragments of skulls, vertebrae and ribs to a very well-preserved femur.”

“In fact, when we started this excavation, we did not expect to find so many fossils of this type of animal in Mallorca.”

“If you saw this animal walking down the street, you would think it would look a little like a medium-sized dog, maybe about the size of a husky, but that’s not entirely true,” says Dr. Angielczyk.

“It didn’t have any fur, and it probably didn’t have dog ears.”

“But this is the oldest animal with long, blade-like canine teeth that scientists have ever discovered.”

“These saber-like teeth suggest that this gorgonopsid was the top predator of its time.”

The fact that this gorgonopsian is tens of millions of years older than its closest relatives has changed scientists’ understanding of the evolutionary time of therapsids, key milestones to the emergence of mammals, and, by extension, where we came from. It tells us something about Tanoka.

“Before the age of dinosaurs, there was the age of our ancient mammalian relatives,” Dr. Angielczyk said.

“Most of those ancient mammal relatives looked nothing like what we think of as mammals today.”

“But they were really diverse and had different ecological roles.”

“This new fossil discovery is another piece of the puzzle of how mammals evolved.”

This finding is reported in the following article: paper Published in a magazine nature communications.

_____

R. Matamares-Andrew others. 2024. Early-Middle Permian Mediterranean gorgonopsids suggest an equatorial origin for therapsids. Nat Commune 15, 10346; doi: 10.1038/s41467-024-54425-5

Source: www.sci.news

The eerie tale of a rodent paradise foreshadowing the downfall of mankind

Posted on December 17, 2024 by Igor Mitreski

In June 1972, the Royal Society of Medicine in London hosted a symposium called “Man in His Place.'' The lecture featured a diverse group of speakers, including Jacob Bronowski, who was featured in a highly acclaimed 13-part BBC television series. rise of manwill be broadcast the following year. But the first person to take to the stage was John Bumpass Calhoun of the National Institute of Mental Health in suburban Washington, DC.

Even those in the audience familiar with Calhoun's work had no idea what was in store for them, and the title of his talk, “Death Squared: The Explosive Growth and Demise of Rat Populations” was not conveyed very well. “I mainly talk about rats, but my thoughts are about humans, healing, life and its evolution,” he began. He went on to describe a long-term experiment he is conducting on population dynamics in mice living in a “utopian environment” he calls Space 25. Although his research subjects were rodents, Calhoun believed that his metropolis had an effect on humans. A cautionary tale about the chaos and social collapse that awaits humanity in an overpopulated world.

An ecologist turned psychologist turned futurist, Calhoun became a science rock star in the 1970s. His message resonated at a time when the human population was rapidly expanding and overpopulation was a major political issue. As interest in his research grew, Calhoun was courted by the great and the good, from politicians and urban planners to prison reformers and writers. He also had an audience with the Pope. Strange as it may seem, his rodent city…

Source: www.newscientist.com

An ancient saber-toothed predator roamed 270 million years ago

Posted on December 17, 2024 by Igor Mitreski

Reconstruction of the oldest known gorgonopsian

henry sutherland sharpe

The earliest known sabertooths hunted large prey 270 million years ago. The newly discovered remains could help explain how early mammal relatives became warm-blooded animals.

The first land predators usually hunted relatively small prey. But things changed about 273 million years ago, when an event known as the Olson extinction shook ecosystems around the world. Then, much larger terrestrial herbivores began to appear, and predators needed new weapons to dispatch such large prey. Josep Fortuny At the Miquel Cursafont Catalan Institute of Paleontology, Barcelona, Spain.

This may help explain why the fossilized partial skeleton of an ancient predator that Fortuny and his colleagues just discovered on the Spanish island of Mallorca had saber-shaped teeth. These fangs are better suited for injuring larger prey than for grabbing and holding small animals. “This was the first time we had access to this kind of tool for preying on herbivores,” Fortuny said.

Dating back an estimated 270 million years, this predator is the oldest known member of a group of carnivores known as gorgonopsians, all of whom had saber-shaped teeth. The largest gorgonopsids grew to several meters in length, with canine teeth reaching 15 centimeters in length. The Mallorca gorgonopsian was smaller, measuring about 1 meter long and its canine teeth only 5 centimeters long. Fortuny said researchers are waiting to name the new gorgonopsian until they have analyzed the bones and teeth in more detail.

Ancient predators are important not only because of their age. At the time they roamed Mallorca, the island was part of a tropical supercontinent called Pangea, but all known fossils of gorgonopsids date back 270 million years. They come from areas of the world that were at high latitudes. The new discovery suggests that the gorgonopsian actually originated near the equator.

Perhaps adaptations developed there, such as the ability to efficiently hunt large prey, may have allowed them to regulate their body temperature in order to spread into cooler habitats away from the equator.

Fortuny says it’s important to better understand this process because gorgonopsids belonged to the therapsids, a group of animals that also includes mammals. “There’s a lot of debate about the first steps in thermoregulation in this group,” he says.

topic:

Source: www.newscientist.com

Bronze Age Briton Experiences Brutal Attack and Cannibalism

Posted on December 17, 2024 by Igor Mitreski

New research has revealed that during the early Bronze Age in England, at least 37 people may have been “systematically dismembered” and eaten in the aftermath of “extremely violent” attacks.

The study, published in the journal ancient, revealed that more than 3,000 bones were excavated from a 50-foot hole at Charterhouse Warren in southwest England.

The bones, which were first discovered in the 1970s by cave explorers, showed an “abundance of cut marks,” prompting researchers to conduct further analysis.

Lead author Rick Schulting, a professor of scientific and prehistoric archeology at the University of Oxford, described the violence inflicted on the bodies as exceptional, with victims being killed with blows to the head, systematically dismembered, skinned, and crushed.

The study suggests that this extreme violence likely occurred in a single event between 2210 BC and 2010 BC, making it a unique example of violence in early Bronze Age Britain.

An example of cranial trauma in a Bronze Age skull recovered from Charterhouse Warren.
Antiquity Publications Ltd / Cambridge University Press

This act of violence was likely not isolated and may have sparked a cycle of revenge within and between communities in the Early Bronze Age, according to Mr. Schulting.

The motives behind such attacks are difficult to determine, but the study suggests that tensions may have escalated from accusations of theft and witchcraft, leading to an uncontrollable spiral of violence.

Victims may have been eaten to dehumanize and treat them like animals, involving a large number of aggressors based on the number of victims and the dismemberment process, the study noted.

The bones were found alongside animal fossils, indicating early evidence of slaughter, which the researchers believe was driven by hunger as the attackers had access to plenty of food.

Source: www.nbcnews.com

Physicists at CERN make groundbreaking discovery: Evidence of antihyperhelium-4 detected for the first time

Posted on December 17, 2024 by Igor Mitreski

Physicists are Alice Collaboration. Evidence of antihyperhelium-4 has been seen for the first time at CERN’s Large Hadron Collider (LHC). Antihyperhelium-4 consists of two antiprotons, an antineutron, and an antilambda. New results are also the first evidence of the heaviest antimatter hypernuclear still at the LHC.

Illustration of the production of antihyperhelium-4 in a lead-lead collision. Image credit: AI-assisted J. Ditzel.

Collisions between heavy ions at the LHC created quark-gluon plasma, a hot, dense state of matter that is thought to have filled the universe about a millionth of a second after the Big Bang.

Heavy ion collisions also create conditions suitable for the production of atomic nuclei, exotic hypernuclei, and their antimatter counterparts, antinuclei and antihypernuclei.

Measuring these forms of matter is important for a variety of purposes, including helping to understand the formation of hadrons from quarks and gluons, the building blocks of plasma, and the matter-antimatter asymmetry seen in the modern universe.

Hypernuclei are exotic atomic nuclei formed by a mixture of protons, neutrons, and hyperons, the latter of which are unstable particles containing one or more strange types of quarks.

More than 70 years after their discovery in cosmic rays, hypernuclei continue to be a source of fascination for physicists. This is because hypernuclei are rarely found in nature and are difficult to create and study in the laboratory.

Collisions of heavy ions produce large numbers of hypernuclei, and until recently, the lightest hypernuclei, hypertriton (composed of protons, neutrons, and lambda), and its antimatter partner, antihypertriton, have been observed.

Following recent observations of antihyperhydrogen-4, ALICE physicists have detected antihyperhelium-4.

This result has a significance of 3.5 standard deviations and is also the first evidence of the heaviest antimatter hypernucleus ever at the LHC.

The ALICE measurements are based on lead-lead collision data taken in 2018 at an energy of 5.02 teraelectronvolts (TeV) for each colliding pair of nucleons (protons and neutrons).

The researchers examined data for the signals of hyperhydrogen-4, hyperhelium-4, and their antimatter partners using machine learning techniques that go beyond traditional hypernuclear search techniques.

Candidates for (anti)hyperhydrogen-4 were identified by looking for an (anti)helium-4 nucleus and a charged pion with which it decays; identified by. -Three atomic nuclei, an (anti)proton, and a charged pion.

In addition to finding evidence for antihyperhelium-4 with a significance of 3.5 standard deviations and evidence for antihyperhydrogen-4 with a significance of 4.5 standard deviations, the ALICE team found that the production yields of both hypernuclei and measured the mass.

“For both hypernuclei, the measured masses are consistent with current global average values,” the scientists said.

“The measured production yields were compared with predictions from a statistical hadronization model that adequately accounts for the formation of hadrons and nuclei in heavy ion collisions.”

“This comparison shows that the model's predictions closely match the data when both the excited hypernuclear state and the ground state are included in the prediction.”

“This result confirms that the statistical hadronization model can also adequately explain the production of hypernuclei, which are compact objects about 2 femtometers in size.”

The authors also determined the antiparticle-to-particle yield ratios for both hypernuclei and found that they agreed within experimental uncertainties.

“This agreement is consistent with ALICE's observation that matter and antimatter are produced equally at LHC energy and further strengthens ongoing research into the matter-antimatter imbalance in the Universe.” concluded.

Source: www.sci.news

Protoplanetary disks surrounding stars similar to the Sun seem to have had a longer lifespan in the early universe

Posted on December 17, 2024 by Igor Mitreski

In 2003, Hubble provided evidence of giant exoplanets around very old stars. Such stars have only small amounts of the heavy elements that make up planets. This suggests that some planetary formation occurred when our universe was very young, and that those planets had time to form and grow large within the primordial disk, becoming even larger than Jupiter. I am. But how? To answer this question, astronomers used the NASA/ESA/CSA James Webb Space Telescope to study stars in the nearby Small Magellanic Cloud, which, like the early Universe, lacks large amounts of heavy elements. They discovered that not only do some stars there have planet-forming disks, but that those disks are longer-lived than the disks found around young stars in our Milky Way galaxy.

This web image shows NGC 346, a massive star cluster in the Small Magellanic Cloud. Yellow circles superimposed on the image indicate the positions of the 10 stars investigated in the study. Image credits: NASA/ESA/CSA/STScI/Olivia C. Jones, UK ATC/Guido De Marchi, ESTEC/Margaret Meixner, USRA.

“With Webb, we have strong confirmation of what we saw with Hubble, and we need to rethink how we model planet formation and early evolution in the young Universe.” European Space Research Agency said Dr. Guido de Marchi, a researcher at Technology Center.

“In the early universe, stars formed primarily from hydrogen and helium, with few heavier elements such as carbon or iron, and were later born from supernova explosions.”

“Current models predict that because heavy elements are so scarce, the lifetime of the disk around the star is short, so short that in fact planets cannot grow,” said a researcher at NSF's NOIRLab's Gemini Observatory. said lead scientist Dr. Elena Sabbi.

“But Hubble actually observed those planets. So what happens if the model is incorrect and the disks have a longer lifespan?”

To test this idea, the astronomers trained Webb in the Small Magellanic Cloud, a dwarf galaxy that is one of the closest galaxies to the Milky Way.

In particular, they examined the massive star-forming cluster NGC 346, which also has a relative lack of heavy elements.

This cluster served as a nearby proxy for studying stellar environments with similar conditions in the distant early universe.

Hubble observations of NGC 346 since the mid-2000s have revealed that there are many stars around 20 to 30 million years old that are thought to still have planet-forming disks around them.

This was contrary to the conventional idea that such disks would disappear after two or three million years.

“Hubble's discovery was controversial and went against not only the empirical evidence for the galaxy, but also current models,” Dr. De Marchi said.

“This was interesting, but without a way to obtain the spectra of these stars, we will not know whether what we are witnessing is genuine accretion and the presence of a disk, or just an artificial effect. I couldn't actually confirm it.”

Now, thanks to Webb's sensitivity and resolution, scientists have, for the first time, spectra of the formation of Sun-like stars and their surrounding environments in nearby galaxies.

“We can see that these stars are actually surrounded by a disk and are still in the process of engulfing material even though they are relatively old, 20 or 30 million years old,” De Marchi said. Ta.

“This also means that planets have more time to form and grow around these stars than in nearby star-forming regions in our galaxy.”

This discovery contradicts previous theoretical predictions that if there were very few heavy elements in the gas around the disk, the star would quickly blow away the disk.

Therefore, the lifespan of the disk is very short, probably less than 1 million years.

But how can planets form if dust grains stick together to form pebbles and the disk doesn't stay around the star long enough to become the planet's core?

The researchers explained that two different mechanisms, or a combination of them, may exist for planet-forming disks to persist in environments low in heavy elements.

First, the star applies radiation pressure to blow the disk away.

For this pressure to be effective, an element heavier than hydrogen or helium must be present in the gas.

However, the massive star cluster NGC 346 contains only about 10 percent of the heavy elements present in the Sun's chemical composition.

Perhaps the stars in this cluster just need time to disperse their disks.

A second possibility is that for a Sun-like star to form when there are few heavier elements, it would need to start with a larger cloud of gas.

As the gas cloud grows larger, it produces larger disks. Therefore, because there is more mass in the disk, it will take longer to blow it away, even if the radiation pressure is acting the same.

“The more material around the star, the longer the accretion will last,” Sabbi says.

“It takes 10 times longer for the disk to disappear. This has implications for how planets form and the types of system architectures that can be used in different environments. This is very exciting.”

of study Published today on astrophysical journal.

_____

Guido de Marchi others. 2024. Protoplanetary disks around Sun-like stars appear to live longer when they are less metallic. APJ 977,214;Doi: 10.3847/1538-4357/ad7a63

This article is adapted from an original release by the Webb Mission Team at NASA's Goddard Space Flight Center.

Source: www.sci.news

Unusual dental structure discovered in Triassic lizard-like quasi-reptile

Posted on December 17, 2024 by Igor Mitreski

Paleontologists have identified a new species of procolophonid reptile from fossilized skull and jaw fragments found in southwest England.

rebuilding the life of Treodatos casmatos. Image credit: Mark Whitton.

The newly discovered species Treodatos casmatoslived during the Late Triassic period, approximately 220 to 210 million years ago.

The ancient creature is a member of Leptopleuroninaean extinct lizard-like quasi-reptilian subfamily within the clade Procolophonidae.

Luke Mead, a palaeontologist at the University of Birmingham, said: “Procolophoids appeared in the late Permian, persisted until the end-Permian extinction event, and were a notable element of the post-extinction fauna in the Triassic, on the supercontinent. They were small quasi-reptile species that were diverse throughout Pangea.” his colleagues.

“Procolophonid diversity decreased during the Late Triassic and is represented only by the late-divergent clade Leptopleuroninae, known for small occurrences in Brazil, North America, Scotland, England, and possibly Wales. ”

“Leptopleuronin procolophorids typically have a reduced number of laterally expanded bicuspid maxillary teeth and are often characterized by cranial decorations such as enlarged spines of the quadrate zygoma.”

“Leptopleuronins appear to be well adapted to a high-fiber herbivore, omnivore, or entomovore diet, and this group may represent the latest surviving clade of Parareptilia.” There is.”

Fossilized remains are Treodatos casmatos It was discovered at Cromhall Quarry in southern Gloucestershire, south-west England.

“The teeth and jaws of this small reptile exhibit features never before seen in this group,” said Dr. Mead, lead author of the paper. study Published in a magazine Paleontology Papers.

“They probably fed differently than their relatives, raising new questions about how these animals interacted with their environment during the Late Triassic. ”

Reptiles have tricuspid teeth in their upper jaws, each with three distinct points. The lower jaw, on the other hand, has compressed unicuspid teeth with unusual edentulous (toothless) tips.

These adaptations may have facilitated unique methods of food processing.

Dr Mark Jones, curator of fossil reptiles at the Natural History Museum, said: “The interaction between the upper and lower teeth is interesting and there are some mammalian similarities in the shape of the teeth.”

“The mandible was not fused at the jaw area; instead, the connection was held by soft tissue and was probably flexible.”

“This flexibility may have allowed the lower jaws to make contact in a way that made it easier to masticate food.”

“This feature is not seen in closely related species and may indicate a specialized diet or feeding strategy.”

“The Late Triassic was a period of dramatic environmental change when Pangea began to collapse.”

“The unique adaptation of teeth is Treodatos casmatos This suggests that they may have carved out a unique ecological niche in a changing climate, feeding on plants, insects, or other small prey that required specialized oral food processing. ”

“Treodatos casmatos “They lived at a time when solar radiation was much lower than it is today, but there was much more carbon dioxide in the atmosphere,” Dr. Jones said.

“It has become generally hotter, global average sea levels have risen, and extreme rainfall events have occurred.”

“therefore, Treodatos casmatos And the communities it lived in may provide perspective on today's threatened ecosystems and the global emergency we face. ”

_____

Luke E. Mead others. 2024. A new protocolophonid with complex tooth rows that lived in the Late Triassic of southwestern England. paleontology papers 10 (6): e1605;doi: 10.1002/spp2.1605

Source: www.sci.news

Practical Applications of Wild Physics: Building a Time Machine

Posted on December 17, 2024 by Igor Mitreski

The bartender said, “We don't serve time travelers here.” A time traveler enters the bar.

OK, yes, you'll almost certainly regret starting this article with such a lame old joke. Most of us, at some point, have wanted to go back in time to fix a mistake or failure. But that's impossible, right?

Well, not necessarily. Albert Einstein's theory of general relativity suggests that time travel may actually be possible. We know that matter can bend space-time, and if we bend it enough we may be able to create time loops. Of course, there are many caveats, and researchers have yet to present a working time machine. But that didn't stop them from exploring the possibilities.

Here are five ways time travel could be possible, from sci-fi classics to surprising new ideas. It also introduces some thorny practical obstacles that need to be overcome.

1. Prepare the galaxy laser ring

The main problem with time travel is that nothing can travel faster than the speed of light, which is 299,792,458 meters per second. This speed limit maintains causation, the idea that the cause must always come before the effect. Thanks to a quirk of Einstein's special theory of relativity and the fact that space and time are intimately connected, traveling faster than the speed of light messes it up. If we could travel faster than light, we would travel back in time. But you can't do that.

The next best thing is to manipulate the fabric of space-time. in…

Source: www.newscientist.com

Plastic chemicals have been connected to numerous deaths globally

Posted on December 16, 2024 by Igor Mitreski

Plastic food packaging can expose people to chemicals such as bisphenol A (BPA)

Shutterstock/Trong Nguyen

New scientist. Our website and magazine feature science news and long reads by expert journalists covering developments in science, technology, health and the environment. — Plastic food packaging can expose people to chemicals such as bisphenol A (BPA)

Shutterstock/Trong Nguyen

Hundreds of thousands of deaths and millions of heart disease cases worldwide may be linked to chemicals found in common plastic products, and stricter regulations on such toxins are needed. This suggests that there may be potential benefits to public health.

Maureen Cropper researchers from the University of Maryland investigated the effects of oxidation on three chemicals primarily used in plastics: bisphenol A (BPA), di(2-ethylhexyl) phthalate (DEHP), and polybrominated diphenyl ethers (PBDEs). The public health impact of exposure was assessed. BPA and DEHP are used in plastic food packaging, and PBDE is a flame retardant used in some household products such as furniture and electronics.

Based on more than 1,700 studies published to date, the researchers estimated how much people in 38 countries, representing about a third of the world’s population, are exposed to these three chemicals. Three of these countries, the United States, Canada, and South Korea, also have public databases that monitor levels of these chemicals in urine and blood samples, providing more accurate data.

Researchers calculated the health effects caused by these chemicals by combining them with medical records and toxicology reports. Researchers found that in 2015, approximately 5.4 million coronary artery diseases and 346,000 strokes were linked to BPA exposure, and approximately 164,000 deaths among people aged 55 to 64 were caused by DEHP. I discovered that it could be.

Thanks to you rules Since their enactment in the 2000s, the prevalence of these chemicals has decreased in many countries, including the United States, Canada, and Europe. Researchers estimate that approximately 515,000 deaths could have been avoided if exposure to BPA and DEHP in the United States had remained at post-regulation levels since 2003. This highlights the importance for governments and manufacturers to limit the use of hazardous chemicals in plastic products before they reach consumers. says Cropper.

However, it is important to remember that these results are only approximations. “Frankly, I think one of the real limitations is the lack of exposure data on these substances,” Cropper said. This means that estimates may be less accurate for some countries than for others. “It would be a good idea for more countries to actually monitor it.” [exposures to] Examining these and other substances will improve our understanding of their public health burden, she says.

topic:

Source: www.newscientist.com

Recent studies uncover the mechanisms by which Deinococcus bacteria can survive high levels of radiation

Posted on December 16, 2024 by Igor Mitreski

called radiation-resistant bacteria Deinococcus radiodurans It can withstand radiation doses thousands of times higher than what would kill a human. The secret behind this resistance is the existence of a collection of simple metabolites that combine with manganese to form a powerful antioxidant. Now, Northwestern University professor Brian Hoffman and his colleagues have discovered how this antioxidant works.

Deinococcus radiodurans. Image credit: USU/Michael Daly.

First discovered in 1956, Deinococcus radiodurans It is one of the most radiation-resistant organisms known.

It was isolated in an experiment aimed at determining whether high doses of gamma rays could be used to sterilize canned food.

In a new study, Professor Hoffman and co-authors characterized a synthetic designer antioxidant called MDP. Deinococcus radiodurans'Resilience.

They show that the components of MDP, manganese ions, phosphates, and small peptides, form a ternary complex that is a much more powerful protector from radiation damage than when manganese is combined with other individual components alone. I discovered that.

This discovery could ultimately lead to new synthetic antioxidants specifically tailored to human needs.

Applications include protecting astronauts from intense space radiation during deep space missions, preparing for radiation emergencies, and producing radiation-inactivated vaccines.

“This ternary complex is MDP's excellent shield against the effects of radiation,” said Professor Hoffman.

“It has long been known that manganese ions and phosphates together make a powerful antioxidant, but now we discover and understand the 'magical' potency brought about by the addition of a third ingredient. That's a breakthrough.”

“This study provided the key to understanding why this combination is such a powerful and promising radioprotector.”

In a previous study, researchers found that: Deinococcus radiodurans It can withstand 25,000 Grays (or units of X-rays and gamma rays).

But in a 2022 study, Professor Hoffmann and his team found that this bacterium, when dried and frozen, can withstand 140,000 Gy of radiation, 28,000 times the dose that would kill humans. did.

Therefore, if there are dormant frozen microbes buried on Mars, they may have survived the onslaught of galactic cosmic radiation and solar protons to this day.

In an effort to understand radioresistance in microorganisms, researchers investigated a designer decapeptide called DP1.

When combined with phosphate and manganese, DP1 forms the free radical scavenger MDP, which protects cells and proteins from radiation damage.

Professor Michael Daly, from Uniformed Services University, said: “This new understanding of MDP could lead to the development of even more powerful manganese-based antioxidants with applications in areas such as medicine, industry, defense and space exploration. Yes,” he said.

of result will appear in Proceedings of the National Academy of Sciences.

_____

Hao Yang others. 2024. A ternary complex of Mn2+, synthetic decapeptide DP1 (DEHGTAVMLK), and orthophosphate is an excellent antioxidant. PNAS 121 (51): e2417389121;doi: 10.1073/pnas.2417389121

Source: www.sci.news

The age of Saturn’s rings may surpass our previous estimates

Posted on December 16, 2024 by Igor Mitreski

Saturn and its rings photographed by the Cassini spacecraft in 2016

NASA/JPL-California Institute of Technology/Space Science Institute

Modeling studies suggest that Saturn's rings are much older than previously thought and may have formed around the same time as Saturn. But not all astronomers are convinced, and the researchers who were part of the team that calculated that Saturn's rings are relatively young insist that the new findings do not change their findings. are.

For most of the 20th century, scientists believed that Saturn's rings formed with the planet about 4.5 billion years ago. But when NASA's Cassini spacecraft visited Saturn in 2004, it found its rings to be noticeably free of contamination from tiny space rocks known as cosmic dust. This innocent appearance indicated that they were much younger. Estimates for 2023 put their age between 100 million and 400 million years.

now, Ryuki Hyodo in Japan Space Science Institute He and his colleagues calculated that Saturn's rings should be much more resistant to contamination from space dust than previously thought, allowing them to maintain a pristine appearance for long periods of time. Hyodo and his team haven't calculated a new age for the ring, but they suggest it could be as old as Earth, as astronomers once believed.

The researchers then modeled how these particles moved through Saturn's magnetic field, and found that only a small portion settled on the rings, while the majority were drawn into Saturn's atmosphere. It turned out that the object was either destroyed or bounced back into space. “The accretion efficiency of Saturn's rings is only a few percent, which is much smaller than previously assumed,” says Professor Hyodo. This could extend previous ring age estimates by hundreds of millions to billions of years, he said.

Sasha Kemp A member of the team at the University of Colorado Boulder that calculated an earlier, much younger estimate of the age of Saturn's rings, he and his colleagues considered not only the ring's contamination efficiency, but also its contamination efficiency, taking into account the time it would take. He said he used a more complicated method. This is because matter reaches the ring and disappears. The values calculated by Hyodo and his colleagues do not change the overall results for that age, Kempf said. “I'm sure this doesn't mean we really have to go back to square one.”

However, Hyodo argues that times should change dramatically as pollution efficiency declines. “They assumed an efficiency of 10%, but we reported 1%. The equation tells us that it's a billion years, or a billion years.”

Kemp also said that while the new simulation assumes that Saturn's rings are made of solid ice particles, the actual rings are made of soft particles that are much larger in size than what was modeled in the study. He said there was. “If you fire particles into these fairly complex and soft structures, the outcome of such collisions will be very different,” he says.

Hyodo argues that this assumption is standard for many similar studies. “No one knows what kind of effect the difference in ice will have,” says Hyodo. “It may or may not be more efficient.”

Lotfi Ben Jaffer A professor at France's Paris Institute of Astrophysics, who was not involved in either age-estimation study, said the study suggests the rings are not as young as recently claimed. “This is a positive step toward a lack of modeling efforts needed to adequately address the fundamental question of planetary ring system formation and evolution,” he says.

But Hyodo and his team need to improve their modeling to more accurately estimate the ring's contamination, he says, so they can more accurately determine its age.

topic:

Source: www.newscientist.com

Hubble Captures Stunning Image of Barred Spiral Galaxy NGC 2566

Posted on December 16, 2024 by Igor Mitreski

Astronomers using the NASA/ESA Hubble Space Telescope have taken striking new photos of barred spiral galaxy NGC 2566.

The barred spiral galaxy NGC 2566 has a prominent star bar at its center, with spiral arms emerging from each end of the bar. Image credit: NASA / ESA / Hubble / D. Tilker.

NGC2566 It is located in the constellation Leo, about 76 million light years away from Earth.

The galaxy was discovered by German-British astronomer William Herschel on March 6, 1785.

Also known as ESO 495-3, LEDA 23303, or UGCA 138, this galaxy is a member of the PGC 80593 group of at least 16 large galaxies.

“NGC 2566 appears tilted from our perspective, so its disk is almond-shaped, giving the galaxy the appearance of a cosmic eye,” Hubble astronomers said in a statement.

“As NGC 2566 stares back at us, we’ll be looking directly behind it, using Hubble to study the galaxy’s star clusters and star-forming regions.”

“Hubble data is especially valuable for studying stars that are only a few million years old.”

“These stars are bright in the ultraviolet and visible wavelengths to which Hubble is sensitive.”

Using these data, astronomers will measure the ages of NGC 2566’s stars, helping them piece together the timeline of star formation in the galaxy and gas exchange between the star-forming clouds and the stars themselves.

“Several other observatories have investigated NGC 2566, including NASA/ESA/CSA’s James Webb Space Telescope,” the researchers said.

“Webb’s data complement this Hubble image, adding a view of NGC 2566’s warm, glowing dust to Hubble’s stellar portrait.”

“NGC 2566, at the long wavelength end of the electromagnetic spectrum, has also been observed by the Atacama Large Millimeter/Submillimeter Array (ALMA).”

“ALMA is a network of 66 radio telescopes working together to capture detailed images of the gas clouds where stars form.”

Source: www.sci.news

What is the reason for furry animals wagging wet dogs?

Posted on December 16, 2024 by Igor Mitreski

Most pet owners have probably seen their furry friends get soaking wet. After dripping for 1 second, they spray water everywhere. wet dog shake. Almost all hairy mammals, from dogs, cats, and mice to lions, tigers, and bears, shiver and dry when their fur gets wet. But even though it's common for dogs to get wet and shiver, scientists still don't know what causes this behavior.

Our skin is very sensitive to touch. Most people can easily distinguish the gentle touch of a loved one, a breeze, the movement of a pest on the skin. We sense touch through our nervous system using specialized cells called . somatosensory neurons Detect changes in our skin. Hairy animals have 12 unique types of somatosensory neurons that sense and respond to touch. One such neuron is C-LTMRresponds only to mild, slow stimuli. When these neurons sense something, they react strongly by sending strong electrical signals through the nervous system. The research team wondered if these neurons were responsible for the tremors in wet dogs.

To investigate the link between C-LTMR neurons and wet dog tremors, the researchers first measured this behavior in mice. They used a dropper to place droplets of sunflower seed oil on the necks of 10 mice and monitored their behavior for five minutes. Mice initiated wet dog shaking within an average of 10 seconds after droplet placement, often 3 to 4 times every 18 seconds. After the first minute, the mice stopped shaking frequently and instead groomed and scratched themselves.

So the researchers wanted to know whether the shivering in wet dogs was an automatic behavior triggered by neurons that sensed these droplets. To test this, they used genetic engineering techniques. crisper In order to remove the genes that create touch sensors in neurons, piezo 2. CRISPR is piezo 2 Gene for finding mouse cells themselves piezo 2 gene. CRISPR then disrupts the gene, preventing the mouse cells from making touch sensors. When researchers placed oil drops on the necks of genetically engineered mice, wet dog shakes did not occur. The researchers concluded that touch is the main mechanism that triggers the automatic shivering behavior in wet dogs.

Many somatosensory neurons use Piezo2 to sense touch, so the researchers are unable to pinpoint the neurons responsible for the wet dog's tremors. However, some genes are only produced by certain types of neurons. The researchers used genetic engineering to target these genes, a process called light-sensitization. optogenetics. These light-sensitive genes produce proteins that become activated when scientists shine a blue laser on them. The researchers used optogenetics to create light-sensitive C-LTMR neurons and compared them to other light-sensitive somatosensory neurons.

When the researchers shined a light on the skin of seven light-sensitive C-LTMR mice, the mice shivered 60% of the time like a wet dog. But mice with other light-sensitive neurons did not show the dog-wetting tremors in response to the laser. The researchers found that photosensitive C-LTMR mice responded best 80% of the time when the laser was applied to the neck rather than the back or thighs, with 30% and 0% responses, respectively. Ta.

The researchers thought this might indicate that C-LTMR neurons were sending signals through other neurons in the spine. spinal parabrachial neurons or SPN. To test this, the researchers cultured SPNs containing optogenetic C-LTMR neurons in Petri dishes. When they shined a laser on C-LTMR neurons, the electrical signals within the SPN were measured with electrodes, showing that these neurons were communicating.

The researchers concluded that wet dog tremors are caused specifically by C-LTMR neurons in the spine. They hope that future studies can build on their findings and gain a deeper understanding of the connections between C-LTMR neurons and the brain. Continuing these studies will impact how scientists understand wet dog tremors in mammals and how hypersensitivity and other contact-based symptoms develop in humans. Possibly.

Post views: 77

Source: sciworthy.com

Newly Discovered ‘Vampire’ Hedgehog Found Among 234 New Species in Asia

Posted on December 16, 2024 by Igor Mitreski

Vampire-like Hedgehog Hylomys Macaron

Alexei V. Abramov

In 2023, scientists in Southeast Asia’s Greater Mekong River region described an astonishing 234 new species. The discovery was announced in 2023. Report from the nature conservation organization WWF173 species of plants, 26 species of reptiles, 17 species of amphibians, 15 species of fish, and 3 species of mammals.

Since 1997, more than 3,500 new plant and vertebrate species have been identified in the region covered by this report, which includes Cambodia, Laos, Myanmar, Thailand and Vietnam, with an average of 130 new species per year. I’m going up.

Here, we introduce six new species, including a hairy hedgehog named after a vampire, an almost invisible dragon lizard, and an endangered leafless orchid.

Hiromiz macaron

The furry hedgehog family pictured above is endemic to Vietnam. Hiromiz macaron It may seem innocuous, but its name is Macaron Means vampire in Vietnamese. It gets its name thanks to its long, pointed fangs, which remain hidden in this photo.

Hyposideros Kingston

This small leaf-nosed bat lives from Thailand to Borneo. confirmed by DNA analysis Hyposideros Kingston It was born as a new species in 2023.

It’s not known where these tiny bats, which weigh just 4.9 to 7 grams, roost. It has been seen near large limestone caves, suggesting that it may be hiding there, but it is also possible that it lives far from known caves, hiding in the hollows of trees. It is also possible that they are building a roost.

Laodracon calusticola

You need keen eyesight to spot this small lizard (Laodracon calusticola), which lives high on the tops of rugged karsts in Laos, which may explain why this species has been ignored by scientists until now. One of the earliest known sightings of this lizard was by a zipline tour guide.

Zhangixalus melanoleucus

This lime green tree frog (Zhangixalus melanoleucus) was discovered at an altitude of 2000 meters in the evergreen forest of Mount Phu Samsoon in northern Laos. Although the region is home to many other endemic species, it is one of the least studied regions in Asia.

Source: www.newscientist.com

The mystery of how the pyramids were built could soon be solved

Posted on December 15, 2024 by Igor Mitreski

The mystery of how the Egyptian pyramids were built has puzzled researchers for centuries. Constructed over 4,000 years ago as burial sites for pharaohs, there are still over 100 pyramids remaining. The largest, the Great Pyramid of Giza, originally stood at 147 meters (482 feet) in height.

Comprised of around 2.3 million stone blocks, each weighing between 2.5 and 15 tonnes, the construction required innovative methods to transport and lift the heavy stones. Different theories exist among scientists regarding the techniques used to achieve such great heights,” says Dr. Eman Ghoneim, a Professor at the University of North Carolina Wilmington in the United States.

Eman Ghoneim on Egypt's Giza Plateau with the Great Sphinx and the pyramids of Khufu, Khafre and Menkaure – Photo credit: UNCW/Eman Ghoneim

Recent research has shed light on some aspects of pyramid construction. One prevailing theory suggests the use of ramps to move the stones, supported by the discovery of sloped structures near some pyramids. Dr. Roland Enmarch, a Senior Lecturer in Egyptology at the University of Liverpool, and his team unearthed groundbreaking evidence of quarry ramps in eastern Egypt used in pyramid construction.

Construction schedules were also crucial in the building of pyramids. It is believed that the Great Pyramid of Giza took 20 years to complete, starting at the beginning of a pharaoh’s reign. Archaeologist Frank Müller-Römer has proposed various ramp designs for pyramid construction, emphasizing the importance of multiple ramps placed along the exterior of the structure.

Construction Schedule

Various techniques like levers, cranes, and pulleys were likely employed in addition to ramps. In a study by Xavier Landreau and his team in Paris, a hydraulic lift system was proposed as a method to build the Step Pyramid of King Djoser. However, some experts question the feasibility of such systems based on archaeological evidence.

Research using scanning techniques is ongoing to explore the internal structure of the Great Pyramid of Giza. The ScanPyramids project by teams from Egypt and France aims to uncover hidden spaces within the pyramid using advanced imaging technologies.

Identifying Supply Lines

Transporting materials to the construction site was a logistical challenge. Researchers like Dr. Ghoneim and his team used satellite images and ground surveys to uncover ancient tributaries of the Nile River that were crucial for transporting goods to the pyramids. These discoveries shed light on the transportation methods used by ancient Egyptians.

Archaeologists have also unearthed logbooks detailing the construction activities at the Great Pyramids of Giza, dispelling myths of supernatural involvement. Ongoing excavations of workers’ quarters near the pyramids provide insight into the organizational aspects of pyramid construction.

About our experts

Dr. Eman Ghoneim, a professor at the University of North Carolina Wilmington, specializes in geographic information systems and remote sensing.

Dr. Roland Enmarch, a Senior Lecturer in Egyptology at the University of Liverpool, has extensive experience in ancient Egyptian research.

Frank Muller Roemer, a German archaeologist and Egyptologist, focuses on ancient Egyptian construction and transportation techniques.

Source: www.sciencefocus.com

Tonight’s Geminid Meteor Shower: A Guide to Viewing the Dazzling Meteors in 2024

Posted on December 14, 2024 by Igor Mitreski

Prepare yourself with a coat, warm socks, and a chair to witness the spectacle of the night sky. The Geminid meteor shower is approaching, offering a breathtaking display of colorful meteors painting the heavens. While this year may not be as spectacular as the previous one, the shooting stars are still worth observing.

So, when will the 2024 Geminid meteor shower occur? The peak is set for the late hours of Friday, December 13th, continuing into the early hours of Saturday, December 14th. This prime time presents the best opportunity to witness these shooting stars, visible to the naked eye with their vivid hues.

According to Dr. Shyam Balaji, a researcher in astroparticle physics and cosmology at King’s College London, the optimal viewing time is around 2 a.m. local time. However, the meteor shower can be observed from the evening onwards. The shower will remain active from December 4th to December 20th, allowing for extended viewing opportunities.

No special equipment is needed to enjoy the meteor shower, just warm clothing, a sense of adventure, and your eyes to gaze at the spectacle.

https://c02.purpledshub.com/uploads/sites/41/2024/12/GettyImages-1946734116.mp4

Time-lapse of the Geminid meteor shower taken in Thailand in 2023

However, with a full moon on Sunday, some of the fainter meteors may be obscured, as noted by Professor Don Polacco, an astrophysicist at the University of Warwick.

Despite suboptimal conditions this year, the Geminid meteor shower is always worth witnessing. So, if weather permits, grab your warm attire, settle into your chair early Saturday morning, and behold the wonder above.

Looking up to observe the meteor shower, locate the constellation Gemini, the radiant point of the shower. Find Orion the Hunter and then spot Castor and Pollux above and to the left for a guide to Gemini’s location in the sky.

The Geminid meteor shower has been known to produce 120 to 150 meteors per hour during its peak, offering a dazzling display of bright meteors streaking across the sky.

These meteors exhibit varying colors, from white, yellow, and green to red, orange, and blue, depending on the metals present in the debris and their interaction with Earth’s atmosphere.

The Geminid meteor shower was particularly bright in 2023 – Credit: NurPhoto / Contributor

The Geminid meteor shower is unique as it originates from asteroid 3200 Phaethon, referred to as a “rocky comet.” These denser fragments result in a more spectacular show than typical comet debris. The close proximity of the shower’s orbit to the Sun also adds to its distinctive qualities.

Get ready to witness the magic of the 2024 Geminid meteor shower and enjoy the celestial spectacle it has to offer.

Source: www.sciencefocus.com

New research indicates that Jupiter’s moon Io does not have an underground magma ocean

Posted on December 14, 2024 by Igor Mitreski

Juno and Galileo’s volcanic activity on Io, Jupiter’s innermost Galilean moon and the most volcanically active object in the solar system, is unlikely to originate from a global magma ocean just below the surface. Deep space networks and astronomical observations, according to new analysis of Doppler data.

The internal structure of Io revealed by this research. Image credit: Sofia Shen / NASA / JPL / Caltech.

Slightly larger than Earth’s moon, Io is the most volcanically active object in the solar system.

It is the innermost of Jupiter’s Galilean moons, which in addition to Io includes Europa, Ganymede, and Callisto.

Trapped in a gravitational tug of war between Jupiter, Europa, and Ganymede, Io is constantly squeezed, causing frictional heat to build up within its interior, which is thought to be the cause of sustained and widespread volcanic activity.

Volcanic activity on the Moon was first discovered in 1979. That’s when Linda Morabito, an engineer on NASA’s Voyager program, spotted an eruption plume in one of the images taken by the spacecraft during its famous Grand Tour of the outer planets.

Since then, countless observations have been made from both space telescopes and telescopes on Earth documenting Io’s restless nature.

“Io is Galileo’s innermost moon, orbiting Jupiter every 42.5 hours,” said Juno collaborator Dr. Ryan Park of NASA’s Jet Propulsion Laboratory and colleagues.

“It has an average diameter of 3,643 km and a bulk density of 3,528 kg/m.³ As such, it is approximately 5% larger than the Moon, both in diameter and density.”

“Io’s eccentric orbit changes its distance from Jupiter by about 3,500 km, which leads to fluctuations in Jupiter’s gravitational pull.”

“Similar to the Moon’s tides caused by Earth, these gravitational fluctuations cause tidal deformations on Io, which are theorized to serve as the main energy source for the intense volcanism and infrared radiation observed on Io’s surface.”

The amount of tidal energy could be enough to cause Io’s interior to melt, potentially forming a magma ocean underground, but this theory is controversial.

Measuring the extent of Io’s tidal deformation could help determine whether the shallow magma ocean theory is plausible.

“Since the discovery of Morabito, planetary scientists have wondered how volcanoes were fed by lava beneath the Earth’s surface,” said Scott Bolton, Ph.D., principal investigator at Juno and a researcher at the Southwest Research Institute.

“Was there a shallow ocean of white-hot magma that fueled the volcano, or was the source more local?”

“We knew data from Juno’s two very close approaches could give us insight into how this beleaguered satellite actually works.”

Io’s arctic region was captured by NASA’s Juno on December 30, 2023, during the spacecraft’s 57th approach to the gas giant. Image credit: NASA / JPL-Caltech / SwRI / MSSS / Gerald Eichstädt.

NASA’s Juno spacecraft flew very close to Io in December 2023 and February 2024, coming within about 1,500 km of the surface.

During its approach, Juno communicated with NASA’s Deep Space Network and acquired high-precision dual-frequency Doppler data. This data was used to measure Io’s gravity by tracking how it affects the spacecraft’s acceleration.

Combining these observations with archival Doppler data from NASA’s Galileo mission and ground-based telescopes, the researchers calculated how much Io is deformed by tidal forces.

This result is inconsistent with what would be expected if a shallow global magma ocean existed, suggesting that Io has a nearly solid mantle.

It is not yet known whether there are regions of magma deep within the moon.

The findings show that tidal forces do not necessarily create global magma oceans, which could have implications for our understanding of other moons such as Enceladus and Europa.

“Juno’s discovery that tidal forces don’t always produce global magma oceans not only prompts us to rethink what we know about Io’s interior,” Dr. Park said.

“It has implications for our understanding of other moons such as Enceladus and Europa, as well as exoplanets and super-Earths.”

“Our new findings provide an opportunity to rethink what we know about planet formation and evolution.”

The team’s paper published in this week’s magazine nature.

_____

RS Park others. Due to Io’s tidal reactions, shallow magma oceans do not form. nature published online on December 12, 2024. doi: 10.1038/s41586-024-08442-5

Source: www.sci.news

Peak of Geminid Meteor Shower and Shooting Stars Set for Friday night to Saturday

Posted on December 14, 2024 by Igor Mitreski

overview

The annual Geminid meteor shower is scheduled to peak Friday night and early Saturday.
It is usually one of the best and most reliable meteor showers of the year.
Stargazers can also look for Jupiter and three bright star formations known as the Winter Triangle.

Stargazers may have something to look forward to this weekend, as the annual Geminid meteor shower peaks Friday night into early Saturday morning.

The meteor shower has been going on all month, but the number of shooting stars is expected to increase into the weekend, especially after midnight Friday and in the pre-dawn darkness. According to NASA.

The Geminid meteor shower can be seen in the northern and southern hemispheres, but a nearly full moon could wash out some faint shooting stars in this year’s show.

Still, the Geminid meteor shower is typically one of the best and most reliable meteor showers of the year, so when conditions are clear, skywatchers can spot bright meteors streaking the night sky. You can do that.

Under ideal sky viewing conditions, with no bright moonlight and little interfering light pollution, you can see as many as 120 Geminid meteor showers per hour.

The Geminid meteor shower was observed in Mumbai, India on December 14, 2017.
Pratik Chorge / Hindustan Times / Getty Images File

As their name suggests, Geminid meteors appear to stream from the constellation Gemini, but skywatchers should be able to see the shooting stars without looking directly into the constellation.

NASA experts suggest lying on your back with your feet facing south to enjoy the Geminid meteor shower. It is best to choose a dark viewing location, away from city lights and other light pollution.

Unlike most other meteor showers, which are caused by comet debris that has burned up in Earth’s atmosphere, the Geminid meteor shower is the remains of an asteroid known as 3200 Phaethon.

If you’re planning on checking out the meteor shower this weekend, be sure to also look for Jupiter in the night sky. The planet lies between the nearly full moon and the brightest reddish-orange star in the constellation Taurus, called Aldebaran, and is visible to the naked eye.

Meanwhile, all winter long, skywatchers in the Northern Hemisphere also have the chance to spot the Winter Triangle, a three-bright star formation. This celestial triangle, consisting of Sirius in the constellation Canis Major, Procyon in the constellation Canis Minor, and Betelgeuse in the constellation Orion, stands out in the winter sky.

To see the Winter Triangle, first look for the three stars that make up Orion’s distinctive band. A little below and to the left of the belt is Sirius, the brightest star in the night sky. From there Procyon is a little higher and to the left. Betelgeuse can be seen by looking back toward the constellation Orion, and the shoulder of the constellation appears red.

Source: www.nbcnews.com

After a decade of increases, obesity rates among U.S. adults decreased last year.

Posted on December 13, 2024 by Igor Mitreski

overview

Last year, the obesity rate among U.S. adults decreased slightly for the first time in more than a decade, a study found.
Researchers suggested this may be due in part to the rise of weight loss drugs like Ozempic.
However, other drugs and factors (such as the effects of the coronavirus pandemic) may also have played a role.

Obesity rates among U.S. adults declined slightly last year, according to a study, but it was the first time in more than a decade that the country had seen a downward trend. Part of that may be due to the recent rise of blockbuster weight loss drugs like Ozempic, the study authors said.

The findings of the study were announced on Friday. Journal JAMA Health Forumthe most significant declines were seen in the South, especially among women and adults ages 66 to 75.

The study looked at BMI measurements for more than 16.7 million adults from 2013 to 2023 across different regions, age groups, genders, races, and ethnicities. BMI measurements are a standard but limited method for estimating obesity relative to body weight. Height to length was collected from electronic health records.

Researchers found that the adult obesity rate in the United States decreased from 46% in 2022 to 45.6% in 2023. (These are slightly higher rates than the U.S. adult obesity rate) Estimate from the center s for disease control and preventionThis means that from 2021 to 2023, approximately 40% of U.S. adults were obese. )

Benjamin Rader, a computational epidemiologist at Boston Children's Hospital and an author of the study, said the results were not uniform across demographics or geographic regions.

“Obesity has been on the decline in the United States as a whole, especially in the South, but this has not been the case in some regions,” he said. “Obesity among Black Americans also decreased significantly, but obesity among Asian Americans increased.”

Rader said the decline in the South was notable because the region observed the highest per capita intake of weight loss drugs, based on researchers' analysis of insurance claims. But he acknowledged that the possible link needed further investigation.

The study authors also noted that obese people in the South had a disproportionately high number of COVID-19 deaths, which may have influenced the overall data.

Dr. Michael Weintraub, an endocrinologist and clinical assistant professor at New York University's Grossman School of Medicine, said the results are consistent with the following: Recent data from the CDC Results showed a slight decrease in obesity prevalence among U.S. adults from 2021 to 2023 compared to 2017 to 2020 (although severe obesity increased during this period). ).

“This data is interesting and holds the promise that we may be on the cusp of changing this obesity epidemic,” said Weintraub, who was not involved in the new study. “However, I would hesitate to call the value of this downward trend in 2023 a trend.”

Even if weight loss drugs were the main factor in reducing obesity, experts say further studies over longer periods of time are needed to assess the true effects of new drugs.

“We know these drugs are very effective, but we need a few more years to see if this is really a trend, or if it's just a small spike and we're back to normal, or if things get much worse. Dr. Tannaz Moin, an endocrinologist and associate professor of medicine at the University of California, Los Angeles, said he was not involved in the study.

Moyn also pointed out that the new study only analyzed preparations of GLP-1 weight loss drugs (a category that includes Ozempic and Mounjaro). This type of drug is used to treat diabetes and obesity by reducing a person's appetite and food intake. This drug mimics the hormone that makes you feel full.

But GLP-1 drugs are only part of the prescription for treating obesity, and a more comprehensive study of different drugs could better capture changing trends, Moyn said. said. Weight loss drugs are also expensive, which can skew data about who can receive treatment.

Additionally, the study used insurance claims data, meaning those who were uninsured or who purchased weight loss drugs out of pocket were likely not included in the results.

Moin said he was surprised by the decline in BMI seen in older people.

“This group is not necessarily the group that I think is the biggest user of GLP-1 drugs, because a lot of them are in the Medicare age group,” she says, adding that weight loss drugs are the most popular for people on Medicare. may be difficult to obtain, he added. The Biden administration recently proposed a rule that would require Medicare and Medicaid to cover weight loss drugs for people seeking obesity treatment.

However, Weintraub cautioned that the observed decline does not necessarily indicate a long-term decline.

“We've been fooled until now by fluctuations in obesity prevalence,” he says. “We were excited about the downward trend in childhood obesity rates announced by the CDC in the early 2000s, but in the years since, obesity rates have increased even more.”

Source: www.nbcnews.com

The Adorable Reason Why Cats Get Zoomy After Using the Litter Box

Posted on December 13, 2024 by Igor Mitreski

Zoomies are a hilarious sight. Watching a cat bounce off walls like a pinball is pure entertainment. One moment they’re leaping over furniture, and the next they’re careening into a lampshade. They zip around here, there, and everywhere before inevitably falling asleep.

Most cats will experience zoomies at some point, also referred to as “periods of frenzied random activity” or “FRAP.” This behavior is more common in the early and late hours of the day and is often seen in kittens and young cats.

Zoomies may also occur after a bowel movement, leading to terms like “poo” and “clap ‘n flap.” Several theories exist to explain this behavior.

Photo credit: Kyle Smart

Some believe it may be a response to a dirty litter box, as cats are naturally clean and want to distance themselves from their waste quickly.

Others suggest it could indicate a gastrointestinal issue or digestive illness.

One theory proposes that the behavior harks back to a cat’s wild instincts, as fecal matter can attract predators. By defecating swiftly, cats may avoid drawing unwanted attention.

https://c02.purpledshub.com/uploads/sites/41/2024/12/GettyImages-1457965473.mp4

Zoomies are also known as Frenetic Random Activity Periods (FRAP).

On a different note, gastroenterologist and author Dr. Anish Sheth hypothesized that large stools could stimulate the vagus nerve, which connects the brain to abdominal organs.

This stimulation may decrease heart rate and blood pressure, leading to reduced blood flow to the brain and potential dizziness. The outcome? A goofy moment of cat craziness, or zoomies.

While this theory is intriguing, conventional wisdom suggests that vagus nerve activity typically relaxes animals rather than making them more active. As a result, the debate continues.

This article explores the question “Why do cats get zoomy after pooping?” posed by Ann Rosales via email.

If you have any queries, feel free to reach out to us at: questions@sciencefocus.comor message us on Facebook, Twitter, or visit our Instagram Page (please include your name and location).

Explore more ultimate fun facts on our fascinating science pages.

Read more:

Source: www.sciencefocus.com

Newly Uncovered Massive Energy Reserve Found Beneath Earth’s Crust

Posted on December 13, 2024 by Igor Mitreski

The issue of energy consumption and its sources has always been a significant concern in the context of the climate crisis. In response, efforts are being made to utilize cleaner and newer fuels. Recently, a groundbreaking discovery of vast reservoirs of hydrogen energy hiding beneath the Earth’s surface has emerged, prompting questions about its potential impact.

Naturally occurring geological hydrogen is formed through Earth’s geochemical processes and has been identified in limited locations such as Albania and Mali. Research published in the journal Scientific Progress suggests that these reserves are widespread globally.

The study posits that if just 2 percent of the underground hydrogen could be extracted, it could yield 1.4 × 10^16 Joules of energy, equivalent to the world population’s energy consumption in 35 minutes. This amount of energy exceeds that of all natural gas reserves on Earth and could aid in achieving net-zero carbon goals.

While current methods for obtaining hydrogen involve fossil fuels or water-intensive electrolysis processes with a carbon footprint, extracting geological hydrogen is a comparatively low-carbon process, albeit currently practiced only in Mali.

Researchers at the U.S. Geological Survey have developed a model combining knowledge of hydrogen occurrence and geological data to explore these reservoirs on a global scale, estimating a substantial amount of hidden hydrogen beneath the Earth’s surface.

However, experts are hesitant about committing resources to extraction due to the scale and infrastructure required, as highlighted by geoscientist Professor Bill McGuire from University College London (UCL). He emphasizes the abundance of renewable energy sources like wind and solar and questions the necessity of tapping into another finite resource.

About our experts

Professor Bill McGuire is a volcanologist, climatologist, and author currently serving as Professor of Geophysics and Climate Hazards at UCL. His works include books on natural disasters, environmental change, and climate solutions.

Read more:

Source: www.sciencefocus.com

Research indicates that intermittent fasting may have a major impact on slowing down hair growth

Posted on December 13, 2024 by Igor Mitreski

Intermittent fasting can be effective for weight loss, but it can also have negative effects on hair growth, as shown in a recent mouse experiment conducted by researchers at Westlake University in China. The study found that mice undergoing intermittent fasting experienced improved metabolic health but showed delayed hair regrowth. This link between restrictive eating and hair regrowth was also observed in a study published in Cell.

While similar effects may occur in humans, they are typically less severe due to differences in metabolic rate and hair growth patterns. Nevertheless, it is important to be aware of the potential unintended consequences of intermittent fasting, as highlighted by senior author and stem cell biologist Dr. Bing Zhang.

Further research is needed to fully understand the effects of fasting on hair growth, as current studies have primarily focused on its benefits for blood, muscle tissue supply, and metabolism. The research team at Westlake University conducted experiments on mice to explore the impact of intermittent fasting on hair regrowth, with findings suggesting that prolonged fasting stresses hair follicle stem cells, leading to delayed hair growth.

A small clinical trial involving 49 healthy young individuals showed that time-restricted eating with 18 hours of daily fasting reduced hair growth by an average of 18 percent. However, the researchers caution that the study’s small sample size and short duration may yield different results in larger-scale studies.

Future research will investigate how fasting affects other types of stem cells in the body and its implications for wound healing speed. Despite the potential drawbacks, intermittent fasting remains a popular and beneficial practice for many individuals.

Source: www.sciencefocus.com

Nature foiled an attempt to make the world’s biggest snowflake

Posted on December 13, 2024 by Igor Mitreski

In London, where I live, you forget about white Christmas. The best I can hope for is a storm of pathetic flakes. So this year I’m on a mission to make my own snow. It’s not just snow. To maximize the effect of the festival, we want to create the world’s largest snowflake.

It’s going to be a challenge. Guinness World Records Diameter 38cm, thickness 20cm. This incredible phenomenon was recorded in Montana in January 1887, when rancher Matt Coleman reported seeing snowflakes “larger than milk bread” during a violent storm. To be sure, some experts are skeptical. “If this was falling from the sky, they would probably need to wear crash helmets,” said Douglas Mair, a glaciologist at the University of Liverpool in the UK. Nevertheless, Guinness World Records claims that modern sources corroborate the record.

But wait a minute! There is a postscript. The largest snowflake was 10 millimeters. “A snowflake is a single ice crystal,” says Ken Libbrecht, who took the record-breaking photo in Ontario, Canada, in December 2003. The textbook image of a Christmas snowflake is actually a complete snowflake, but a snowflake is made up of several crystals joined together. So you might be able to break the record by creating the world’s largest snowflake instead. How difficult would it be? “You could grow ice crystals from water vapor,” says Libbrecht, whose lab at the California Institute of Technology makes “designer” snowflakes. “But if you want to look like a snowflake, and you want to actually make a symmetrical snowflake, that’s a tall order.” Obviously, I need help.

Source: www.newscientist.com

First-ever imaging of a novel form of magnetism: alternating current magnetism

Posted on December 13, 2024 by Igor Mitreski

Alternating current magnetism is a unique form of magnetic ordering in which small magnetic components align antiparallel to their neighbors, but the structure housing each element is rotated relative to its neighbors. . Professor Peter Wadleigh and colleagues at the University of Nottingham have shown that this new type of magnetism exists and can be controlled with microscopic equipment.

Mapping of alternating current magnetic order vectors in MnTe. Image credit: Amin others., doi: 10.1038/s41586-024-08234-x.

Magnetic materials are used in a large portion of long-term computer memory and in the latest generation of microelectronic devices.

Not only is this a large and important industry, but it is also a global source of carbon emissions.

Replacing key components with alternative magnetic materials has the potential to lead to significant increases in speed and efficiency, while significantly reducing dependence on rare and toxic heavy elements required by traditional ferromagnetic technology .

Alternating magnets combine the advantageous properties of ferromagnets and antiferromagnets in a single material.

They are more robust, more energy efficient, and have the potential to increase the speed of microelectronic components and digital memory by a factor of 1,000.

“An alternating current magnet consists of magnetic moments pointing antiparallel to neighboring magnets,” Professor Wadley says.

“But each part of the crystal that hosts these tiny moments is rotated relative to its neighboring parts. It's like a twist on antiferromagnetism. But this subtle difference It has a big impact.”

Dr Oliver Amin, from the University of Nottingham, said: “Our experimental work provides a bridge between theoretical concepts and real-world implementation, and illuminates the path towards the development of alternative magnetic materials for practical application. I look forward to that.”

The new experimental study was conducted at the MAX IV international facility in Sweden.

This facility, which looks like a giant metal donut, is an electron accelerator called a synchrotron that generates X-rays.

A magnetic material is irradiated with X-rays, and the electrons emitted from the surface are detected using a special microscope.

This allows us to generate images of magnetism within materials with small feature resolution down to the nanoscale.

“Being the first to confirm the effects and properties of this promising new class of magnetic materials has been a hugely rewarding and rewarding privilege,” said the University of Nottingham PhD. Student Alfred Dal Din.

team's work Published in a magazine nature.

_____

OJ Amin others. 2024. Nanoscale imaging and control of alternating current magnetism in MnTe. nature 636, 348-353;doi: 10.1038/s41586-024-08234-x

Source: www.sci.news

Ancient modern human genome successfully sequenced

Posted on December 13, 2024 by Igor Mitreski

Scientists sequenced and analyzed the genomes of seven people who lived between 42,000 and 49,000 years ago in Ranis, Germany, and Zlatiks, Czech Republic. As a result, the Ranis and Zlati Kush were linked by distant kinship ties, and that they were part of the same small, isolated group, representing the deepest known split from lineages outside Africa. was shown. The Ranis genome contains a Neanderthal component derived from a single admixture event common to all non-Africans, which the authors date back 45,000 to 49,000 years ago. This means that all non-African ancestors sequenced so far existed in a common population during this time, and further The human remains suggest that they represent a distinct non-African population.

Illustration of the Zlati Kush, who belonged to the same group as the Ranis and had close relationships with two of them. Image credit: Tom Björklund / Max Planck Institute for Evolutionary Anthropology.

Dr. Alev Schumer of the Max Planck Institute for Evolution said, “After modern humans left Africa, they met and interbred with Neanderthals, and as a result, approximately 2 to 3 percent of Neanderthal DNA is present in all areas outside Africa.'' It's in people's genomes.” Anthropology and its colleagues.

“However, little is known about the genetics of Europe's first settlers or the timing of interbreeding between Neanderthals and non-Africans.”

“An important site in Europe is Zlaty Kush in the Czech Republic, where the complete skull of a single individual who lived about 45,000 years ago was discovered and previously genetically analyzed.”

“However, due to the lack of archaeological context, we were unable to link this person to an archaeologically defined group.”

“Ilsenhöhle, located in Ranis, Germany, about 230 km from the nearby site Zlatiks, is known for a particular type of archeology, Rincombi-Ranissian-Jersmanovičian (LRJ), dating back about 45,000 years. ”

“It has long been debated whether the LRJ culture was created by Neanderthals or early modern humans.”

“Although most small bone fragments have been preserved at Ranis, previous research was able to analyze mitochondrial DNA from 13 of these remains, indicating that they belong to modern humans rather than Neanderthals. It turns out.”

“However, because mitochondrial sequences represent only a small portion of genetic information, their relationship to other modern humans has remained a mystery.”

In the new study, the authors analyzed the nuclear genomes of 13 specimens taken from Ranis and found that they represented at least six individuals.

Based on the size of the bones, it was determined that two of the children were infants, and that three were genetically male and three were female.

Interestingly, these individuals included mothers and daughters as well as more distant biological relatives.

The researchers also sequenced more DNA from the female skull found in Zlati Kush, producing a high-quality genome for this individual.

“To our surprise, we discovered that there is a fifth or sixth degree genetic relationship between the two people from Zlati Kush and Ranis,” Dr. Schumer said.

“This means that Zlati Kush is genetically part of an extended family of Ranis and likely created LRJ-type tools as well.”

Of the six Ranis bones, one bone is particularly well preserved, in fact, it is the best preserved modern human bone from the Pleistocene for DNA searches.

This allowed the research team to obtain a high-quality genome from this male individual, called Ranis13.

Together, the Ranis13 and Zlatý kůň genomes represent the oldest high-quality living human genome sequenced to date.

Analyzing genetic variation associated with phenotypic traits, scientists found that Ranis and Zlati Kush individuals carried mutations associated with dark skin and hair color, as well as brown eyes. I did. This reflects the recent African origins of this early European population.

By analyzing parts of the genomes of Ranis and Zlati Kush inherited from the same ancestor, the authors found that their populations consisted of at most a few hundred individuals and were spread over a larger area. We estimate that there is a possibility.

They found no evidence that this small early modern human population contributed to later European or other world populations.

The Zlati Kush/Ranis people coexisted with Neanderthals in Europe, raising the possibility that Neanderthals were among their recent ancestors after they migrated to Europe.

Previous studies of modern humans dating back more than 40,000 years have found evidence of recent admixture between modern humans and Neanderthals.

However, no such evidence for recent Neanderthal admixture was detected in the genomes of Zlati-Kush/Ranis individuals.

Illustration by Zlatý kůň/Ranis group. Image credit: Tom Björklund / Max Planck Institute for Evolutionary Anthropology.

“The fact that no such Neanderthal ancestry remains in Ranis and Zlati Kush, while modern human populations that may have later arrived in Europe inherited such Neanderthal ancestry. is an older Zlati Kush/Ranis lineage This could mean that they entered Europe by a different route or may not have overlapped with the areas inhabited by Neanderthals.''Also Max Planck. said Dr. Kay Pruefer of the Institute for Evolutionary Anthropology.

The Zlati Kush/Ranis population represents the earliest divergence from modern human groups that migrated from Africa and later dispersed across Eurasia.

Despite this early separation, the Neanderthal ancestry of Zlatikush and Ranis derives from the same ancient admixture event that can be detected in all peoples outside Africa today.

By analyzing the length of Neanderthal-contributed segments in the high-coverage Ranis13 genome and using direct radiocarbon dating of this individual, researchers found that this common Neanderthal admixture dates back to 45,000 years ago. It was estimated to be 49,000 years old.

Since all modern non-African populations share this Neanderthal ancestry with the Zlati Kush and Ranis, this means that approximately 45,000 to 49,000 years ago, non-African populations of consistent ancestry still existed. It means you must have done it.

Dr Johannes Kraus, a researcher at the Max Planck Institute for Evolutionary Anthropology, said: “These results provide a deeper understanding of the early pioneers who settled in Europe.”

“They also suggest that the remains of modern humans more than 50,000 years old found outside Africa have interbred with Neanderthals and are part of the general non-African population now found in many parts of the world. This indicates that it may not have been the case.”

of findings Published in today's magazine nature.

_____

AP Sumer others. The genomes of the earliest modern humans constrain the timing of admixture with Neanderthals. naturepublished online on December 12, 2024. doi: 10.1038/s41586-024-08420-x

This article is adapted from the original release by the Max Planck Institute for Evolutionary Anthropology.

Source: www.sci.news

Revising the Timeline of Interbreeding Between Neanderthals and Ancient Humans

Posted on December 13, 2024 by Igor Mitreski

overview

Many people carry small pieces of Neanderthal DNA, evidence of interbreeding between Neanderthals and ancient human ancestors.
Two new studies suggest that interbreeding occurred during the limited period when ancient humans left Africa.
Clarifying that timeline narrows the range of possible times for humans to spread to new continents.

The genetic code of many people hides mysteries that have long intrigued scientists. It’s a tiny piece of Neanderthal DNA that persists tens of thousands of years after the species disappears.

Most people outside Africa can attribute about 1% to 2% of their DNA to Neanderthal ancestry.

However, the details of its evolutionary history remain unclear. How often did ancient humans and Neanderthals interbreed? When exactly did it happen? Why did Neanderthals become extinct and why did modern humans survive? That Neanderthal DNA What is it bringing us now?

Two research groups independently analyzed collections of ancient genomes and reached the same conclusions about some of their core questions. published research Published in Nature magazine and thursday science Evidence suggests that ancient humans and Neanderthals interbred for a limited period of time as humans left Africa and migrated to new continents.

The results suggest that a wave of interbreeding occurred approximately 43,500 to 50,500 years ago. Then, over the next 100 generations, most, but not all, of the Neanderthal DNA was culled. The remaining DNA is now associated with traits such as skin pigmentation, immune response, and metabolism.

New findings suggest that this interbreeding event occurred more recently than previous estimates suggested, shifting and narrowing the window during which humans may have spread to places like modern-day China and Australia. That’s what it means.

The importance of fossilized human remains dating back more than 50,000 years, discovered in Europe and other parts of the world, has also been revealed. According to a new study, those populations became extinct and reached an evolutionary dead end.

“Human history is not just a success story. In fact, humans went extinct several times,” said Johannes Krause, author of the Nature paper and professor at Germany’s Max Planck Institute for Evolutionary Anthropology. “There are multiple lineages that we’re identifying now that didn’t affect later people.”

The discovery also shows how adept anthropologists are at reconstructing ancient DNA and analyzing it to infer the course of human history.

Priya Muajani, author of the Science paper and assistant professor of molecular and cellular biology at the University of California, said: “We can look at past events and actually reconstruct what the path we are on will be. It’s a great thing to be able to do.” Berkeley. “Although 50,000 years ago is a long time ago, having genetic data available from these samples really helps paint a more detailed picture.

The two research groups took different approaches to the study.

Moorjani’s group cataloged genomic information from 59 ancient and 275 modern humans who lived between 2,000 and 45,000 years ago. The researchers then analyzed how the distribution and length of Neanderthal DNA in those genomes changed over time.

They determined that the influx of Neanderthal genes into humans occurred about 47,000 years ago and lasted less than 7,000 years. These findings are consistent with archaeological evidence suggesting that Neanderthals and humans overlapped geographically when humans left Africa. Many scientists suspect that the two species crossed paths in the Middle East, but this has not been confirmed.

After interbreeding, natural selection retained some Neanderthal traits and discarded many more.

…

Source: www.nbcnews.com

Can wordplay drive human evolution through resourcefulness?

Posted on December 13, 2024 by Igor Mitreski

You’ll never know who spoke the first sentence or what they said, but you can have fun guessing. Perhaps they came from the mouths of Stone Age men who wanted to defeat their rivals and win the affections of young women. He may have crept up to his girlfriend, surreptitiously pointing at his competitors and whispering words in her ear that translated into English to mean “fuck you.”

Is it ridiculous? Not so, if we are guided by the work of linguist Liljana Progovac. She points out that Charles Darwin described language as “half art, half instinct,” but most who study the evolution of language have ignored the creative element. Her research addresses this issue by focusing on the wordplay involved in compound words such as shit-head, skin-flint, and lily-livered, many of which are now written as single words. I’m starting to fix it. She believes these are language fossils that point to a key stage in the evolution of language, the moment when humans realized they could string two words together to create very short sentences.

Moreover, after collecting examples of such phrases, Progovac noticed that they had something surprising in common. “They’re usually dismissive,” she says. And there may be evolutionary reasons for that.

Language is central to the human experience, but its ancient roots are difficult to study because it leaves no archaeological trace, at least until the invention of writing. Nevertheless, judging by the communication systems of other animals, our ancestors could use simple sounds and…

Source: www.newscientist.com

The Mystery of Missile Detectors and Santa Trackers at the Festival

Posted on December 13, 2024 by Igor Mitreski

early christmas

Today is my vacation. Actually, it's not a vacation. Because of printing schedules, Feedback is writing this festive edition in the first week of December. We ordered a gift for Mrs. Feedback, but we still don't know what Feedback Jr. will get Mrs. Feedback (with Feedback's money). There is no decoration at all. And we're staring down the barrel of multiple school events. We will be asked to dress up in a festive mood for our children. In short, the feedback is moody.

So now seems like a good time to complain NORAD tracks Santaone of those efforts where you can't believe the feedback exists at all. NORAD, of course, is the North American Aerospace Defense Command, and its primary mission is to use a combination of satellites and radar to detect things flying into North American airspace, such as Chinese weather balloons. But on December 24th, an elaborate volunteer-run exercise to track Santa as he travels around the world will take place. You can also call for updates, check out his progress on his website, and follow him on social media.

How this tradition began is interestingly complex. A fact sheet on the NORAD website states: heartwarming story: “NORAD has been tracking Santa since 1955, when a young child accidentally dialed an unlisted telephone number for the Continental Air Defense Command (CONAD). [the precursor to NORAD] Operations Center…She believed she called Santa Claus after seeing an advertisement in the local newspaper. Air Force Col. Harry Shoup, the commander on duty that night, quickly realized the mistake and promised that CONAD would ensure Santa's safe journey from the North Pole. ”

But this story truth?This is difficult to fully elucidate. Details vary by account. How Shoup first reactedto how many times to call I came that first year. However, what is clear is that All this It started at the height of the Cold War. NORAD is inherently scary because it exists to detect incoming nuclear missiles. Its headquarters is literally a bunker dug into the mountain. stunt track santa This was and still is a great way to look cute. On the other hand, if a nuclear war were to begin, NORAD would almost certainly play a key role in it. On the other hand, run the cute Santa Tracker.

But the biggest gripe with feedback on the whole thing is that I'm 90 percent sure this stunt is the inspiration for a new Christmas-themed fantasy-action-comedy-thriller. red one. In the film's stacked qualifiers, Santa's journey is reimagined as a militaristic security operation involving a fighter jet escort and a sort of Arctic secret service commanded by Dwayne Johnson. It looks like one of the worst movies of the year, and I strongly suspect that the feedback is ultimately NORAD Tracks Santa's fault.

long setup

Speaking of tracking immaterial things, an Australian research project is asking people to monitor their own flatulence. It is necessarily Graph a fart.

Using a free phone app, participants cantrack Quantity and quality of output, including attributes such as odor, volume, duration, aftertaste, and detectability. ” feedback appreciates the precisely guided use of the word “residual” and points out that fart residual can be scored from “momentary” to “permanent.”

It aims to further explain “one of the main gut health symptoms experienced by Australians'', specifically “excessive bloating'', which up to 43 per cent of Australians report experiencing almost every day. It's about deepening your understanding.

Feedback is not supported guardianThe heading for the project is “wind power”. We also cannot approve of the decision to limit the study to Australia. But thankfully, others will too, as shown in this amazing 42-page feature on researchers trying to catch farts. And their work is extremely important at this time, when millions of us, in many countries, eat appalling amounts of meat, mince pies, and above all, gas. I'm about to eat some Brussels sprouts.

cheap in price

For all our readers who don't have a present for their loved ones yet, you're out of luck. I missed a great opportunity. London auction house Christie's recently announced the first-ever science fiction and fantasy auctionthe highlights are: dune bible: A circa 1975 collection of behind-the-scenes documents from Alejandro Jodorowsky's unproduced film adaptation of Frank Herbert's book. dunes. This is an ideal excuse for feedback to bring something to our chest. So here we go.

Jodorowsky's dunes The film has an almost mythical status as one of the great assumptions of science fiction cinema. The blockbuster, starring Orson Welles and Mick Jagger, with production design by H.R. Giger (later a director), is expected to be at least 10 hours long. alien fame). If he had succeeded in it, it would have become a classic.

Here's the problem. Jodorowsky is one of the most exaggerated filmmakers to have written a screenplay that included depictions of his own penis. Feedback learned from Danny Peary cult moviecovering Jodorowsky's mysterious 1970 Western. el topo. Peary complained that there were “too many references, Jungian and religious symbols/artifacts…inside jokes, and too many vague images that no one but Jodorowsky knows what's going on.” . Imagine it lasting more than 10 hours. we are saved.

Have a story for feedback?

You can email your article to Feedback at feedback@newscientist.com. Please enter your home address. This week's and past feedback can be found on our website.

Source: www.newscientist.com

The mystery of the unidentified drone soaring over America

Posted on December 13, 2024 by Igor Mitreski

Unidentified drone flies over US military facility

US Navy/Ensign Drew Barbis

A mysterious drone has been flying over New Jersey and neighboring states for a month. they were discovered some us military facility. They are filmed on video from the top of residential and apartment buildings. A swarm was seen chasing a U.S. Coast Guard rescue vessel at the same time New Jersey State Police reported 50 drones arrived on land from the sea. But no one seems to know who's behind the wheel or whether it's an organized effort.

The case has attracted the attention of state governors, legislators and even members of the U.S. Congress, and the FBI has launched an investigation. investigationis asking the public to report sightings.

Witnesses say the drones are as noisy as lawnmowers, some are the size of a small car, and are much louder than the typical quadcopter and multicopter drones that anyone can buy. “These are not necessarily just hobbyist small unmanned aircraft systems that you can buy for $2,000,” he says. Daniel Gerstein at the RAND Corporation, a think tank in California. “These feel like they have longer range and are more sophisticated than what you can get at a hobby shop.”

Blurry nighttime videos are popping up all over social media sharing drone sightings in states like New Jersey, Pennsylvania, and New York, including videos of drones in the sky. It is. Verrazzano Narrows Bridge in New York City. Federal Aviation Administration Drone flight restrictions issued following reports of drone activity over both the Trump National Golf Club and the Picatinny Arsenal military base in New Jersey. This sighting coincides with other drone swarms that have recently appeared near British military bases where US Air Force squadrons operate.

On December 10th, the House Homeland Security Committee held a meeting. hearing He met with officials from the FBI, U.S. Customs and Border Protection, and the U.S. Department of Justice about the drone threat. Officials said recent sightings may include a mix of rotary-wing and fixed-wing drones, but they aren't sure what the drones are doing or who is piloting them. Little information was available. However, he said drones are not yet a serious threat. Separately Briefing session According to information from the U.S. Department of Homeland Security, the agency told lawmakers some sightings may have mistaken the aircraft for a drone.

Mayor Ryan Hurd, from New Jersey, said: said ABC News Live Officials said they confirmed that these were not U.S. military drones and were not operated by a U.S. tech company.

Meanwhile, in the UK, Defense Secretary Vernon Coker told parliament last month that authorities: Under investigation Since November 20th, multiple drone intrusions have occurred near several military bases in the UK. These bases support U.S. Air Force squadrons that fly fighters, bombers, and support aircraft.

“The common theme in all of these incidents is that no one has completely cracked the code on how to spot, track, and, if necessary, shoot down small drones,” he said. arthur holland michelJournalist and author who writes about drones. “The second common theme is that the challenge of countering a drone is through the roof when the person operating the drone is actively trying to avoid being identified.”

Although drones can be tracked with radar and other sensors, “it is still not practical to cover every corner of the country with detection and tracking systems,” and officials say “most of our country's airspace does not allow drones at all.” Michel says that they are often “unrecognizable.” “Typically, by the time a citizen spots a drone and reports it or photographs it with a cell phone, it is too late.” [to take early action]” he says.

Gerstein said there is uncertainty about who has the primary authority and responsibility to take action against these drones, between local law enforcement and state and federal agencies. Even if they are resolved, finding the best way to deal with them is not easy.

Either directly shoot down the drone using missiles, lasers, bullets, or even other drones, or take control of the suspicious drone and use electronic warfare signals to force it to land, Gerstein said. There are many countermeasures against drones. Such techniques have been commonly used during the drone-heavy war in Ukraine, while U.S. Navy warships and other naval vessels shot down dozens of drones threatening shipping in the Red Sea region.

“When shooting down a drone, the most effective method is often the most dangerous,” Michel said. “There is no way law enforcement could fire a sophisticated projectile into the air or activate a military signal jammer every time a drone is spotted flying overhead.” [New Jersey]”

topic:

Source: www.newscientist.com

The frequency of giant solar flares from the sun may be higher than previously believed

Posted on December 12, 2024 by Igor Mitreski

This relatively small solar flare that occurred in October (a bright flash at the center discovered by NASA’s Solar Dynamics Observatory) would be dwarfed by a superflare.

NASA/SDO

The sun can produce extremely powerful bursts of radiation more often than we think. According to research on stars similar to the Sun, such “superflares” appear to occur about once every 100 years, and are particle storms that can have a devastating effect on electronic equipment on Earth. may be accompanied by The last major solar storm to hit Earth was 165 years ago, so we may be hit by another solar storm soon, but how similar is our Sun to these other stars? is unknown.

Direct measurements of solar activity did not begin until the mid-20th century. In 1859, our star produced a very powerful solar flare, or emission of light. These are often associated with subsequent coronal mass ejections (CMEs), bubbles of magnetized plasma particles that shoot into space.

In fact, this flare was followed by a CME that crashed into the Earth, causing a violent geomagnetic storm. This was recorded by astronomers at the time and is now known as the Carrington phenomenon. If this were to happen today, communications systems and power grids could be disrupted.

There is also evidence that there were even more powerful storms on Earth long before the Carrington incident. Assessment of radiocarbon content in tree rings and ice cores suggests that extremely high-energy particles occasionally rained down on Earth over several days, but this could be attributed to a one-time, massive solar outburst. It is unclear whether this is the case or whether it is due to several solar explosions. something small. It’s also unclear whether the Sun can produce such large flares and particle storms in a single explosion.

The frequency of these signs on Earth, and the frequency of superflares that astronomers have recorded on other stars, suggests that these giant bursts tend to occur hundreds to thousands of years apart. .

now, Ilya Usoskin Researchers from the University of Oulu in Finland studied 56,450 stars and found that stars similar to the Sun appear to emit superflares much more frequently.

“Superflares in stars like the Sun occur much more frequently than previously thought, about once every century or two,” Usoskin said. “If we believe this prediction for the Sun is correct, we would expect the Sun to have a superflare about every 100 to 200 years, and the only extreme solar storms we know of occur about once every 1500 or 2000 years. There will be a mismatch.”

Using the Kepler Space Telescope to measure the brightness of stars, Usoskin and colleagues detected a total of 2,889 superflares in 2,527 stars. The energies of these flares were 100 to 10,000 times the size of the Carrington event, the largest flare measured from the Sun.

Usoskin said it remains to be seen whether such large flares also cause large-particle phenomena, such as there is evidence for on Earth, but current solar theory cannot explain such large flares. That’s what it means. “This raises questions about what we’re actually seeing,” he says.

“It’s very impressive for a stellar flare survey,” he says. Matthew Owens At the University of Reading, UK. “They’ve clearly developed a new way to detect flares with increased sensitivity.”

Owens says it’s even harder to determine how much this tells us about the Sun’s flaring activity, in part because it’s difficult to accurately measure the rotation rates of other stars. It is said that it is for the sake of “The devil is in the details,” he says.

“The rotation rate is important because it is related to how the star generates its magnetic field, and magnetic fields are related to flare activity,” Owens said.

topic:

Source: www.newscientist.com

Webb finds evidence of active formation of low-mass galaxies in the early universe

Posted on December 12, 2024 by Igor Mitreski

The newly discovered galaxy, called the Firefly Radiance, existed about 600 million years after the Big Bang and consisted of at least 10 star clusters.

The Firefly Sparkle galaxy is in the process of gathering and forming new stars, exists about 600 million years after the Big Bang, and would weigh about the same as the Milky Way if we could turn back the clock and watch the galaxy develop . Image credits: NASA / ESA / CSA / STScI / C. Willott, NRC-Canada / L. Mowla, Wellesley College / K. Iyer, Columbia.

The most distant galaxies detected date from when the universe was about 5% of its current age.

However, the mass of these galaxies is about 10,000 times smaller than that of the Milky Way, making them difficult to observe.

The Firefly Sparkle galaxy was first observed by the NASA/ESA Hubble Space Telescope, but detailed new observations by the NASA/ESA/CSA James Webb Space Telescope shed more light on its formation.

“We never thought it would be possible to resolve galaxies that existed so early in the universe into so many different components, much less that their mass would be comparable to the mass of our galaxy in the process of forming. “I never thought it would be possible to discover similarities between the two,” he said. Dr. Ramiya Moura, astronomer at Wellesley College.

“There’s so much going on inside this small galaxy, including various stages of star formation.”

Webb was able to image the Firefly Sparkle galaxy in sufficient detail for two reasons.

One is the blessings of the universe. A massive galaxy cluster in the foreground, called MACS J1423.8+2404, radically enhanced the appearance of distant galaxies through a natural effect known as gravitational lensing.

And when combined with the telescope’s specialization in high-resolution imaging in infrared light, Webb provided unprecedented new data on the contents of galaxies.

“Without the benefit of this gravitational lensing, we would not have been able to understand this galaxy,” said Columbia University astronomer Karltej Ayer.

“We knew that was expected based on current physics, but to actually witness it was surprising.”

Astronomers also observed two neighboring galaxies they named Firefly Best Friend and Firefly New Best Friend. These galaxies are located 6,000 and 40,000 light-years from Firefly Sparkle, respectively, and are smaller than the present-day Milky Way.

The authors propose that the firefly glow could be a young, gas-rich galaxy in the early stages of formation.

These show that Firefly Sparkle’s mass is concentrated in 10 star clusters, with a total mass about 10 million times the mass of the Sun.

As such, Firefly Sparkle is one of the lowest-mass galaxies to have resolved into star clusters observed at the dawn of the universe, when galaxies began to form, and its mass is similar to that of the progenitor Milky Way. is.

“It has long been predicted that galaxies in the early universe formed through continuous interactions and mergers with other smaller galaxies,” says Yoshihisa Asada, a doctoral student at Kyoto University.

“We may be witnessing this process in action.”

“We have just started using space microscopy, so this is only the first of many such galaxies that Webb will discover,” said Dr. Marcia Bradač, an astronomer at the University of Ljubljana.

“Just as we can see pollen grains on plants with a microscope, the incredible resolution of the Webb and the magnifying power of gravitational lenses allows us to see tiny pieces inside galaxies.”

“Our team is currently analyzing all the early galaxies, and the results all point in the same direction. We still don’t know much about how these early galaxies formed. .”

of study Published in a magazine nature.

_____

L. Mora others. 2024. Low-mass galaxies were formed from star clusters in the Universe 600 million years ago. nature 636, 332-336; doi: 10.1038/s41586-024-08293-0

Source: www.sci.news

The amusing reason why these monkeys are attracted to long noses

Posted on December 12, 2024 by Igor Mitreski

Proboscis monkeys are renowned for their loud, bulbous calls and are among the most famous primates in the world. Contrary to popular belief, their noses are not so large that they need to be held under their arms when eating. They have a healthy diet.

Endemic to the Southeast Asian island of Borneo, these Old World monkeys are known for their social and friendly nature. They live in troops, with a harem group consisting of dominant males, females, and young males, while bachelor groups may include males and sometimes females.

These monkeys inhabit mangrove swamps and forests near rivers, where they feed on fruits, seeds, and leaves. They prefer unripe fruits due to the high sugar content in ripe fruits, which can cause their already plump bellies to swell further.

Baby proboscis monkeys are born with bright blue faces and black fur, but gradually change to their adult colors as they grow – Photo credit: Getty

They are unique among primates for regurgitating and re-chewing their food (rumination) and have multiple-chambered stomachs similar to cows. The bacteria in their stomachs aid in digesting tough foods and detoxifying them.

Everything about these monkeys is large, from their stomachs accounting for a quarter of their body weight to their long limbs and tails. Males can weigh up to 24 kg (about 52 lbs) and have large noses, earning them the nickname “Orang Branda” or “Dutchman” from local Malays.

Read more:

It turns out that female proboscis monkeys prefer males with large noses, which can grow up to 17 cm (6.5 inches) in length. This trait is sexually selected, with women showing a preference for males with bigger noses due to its association with body quality and vocalization. The size of the nose indicates fertility and influences the male’s success in attracting females.

https://c02.purpledshub.com/uploads/sites/41/2024/12/Monkey.mp4

Male proboscis monkeys use their large noses to make loud noises to attract mates.

Interestingly, males with larger noses also tend to have smaller canine teeth, despite the lack of territorial aggression in proboscis monkeys. Troops of monkeys often interact, and members may move between groups, gathering at night to sleep in the same areas.

Proboscis monkeys are adept swimmers with partially webbed limbs, using a splash-free dog paddle to navigate their habitat. Their main threat comes from human activities like deforestation for timber and agriculture, leading to a drastic decline in their population.

Do you have a science question? To submit your question, email questions@sciencefocus.com or message us on our Facebook, ×, or Instagram page (remember to include your name and location).

Check out our ultimate fun facts and more amazing science pages.

Source: www.sciencefocus.com

A clever young scout attempts to construct a nuclear reactor in his family’s cabin. What ensued?

Posted on December 12, 2024 by Igor Mitreski

Nuclear reactions can be categorized as either fission (when an atomic nucleus splits into two lighter nuclei) or fusion (when two atomic nuclei combine to form a heavier nucleus). You can explore both of these reactions with a simple setup.

Small amounts of radioactive materials can be found in everyday objects, making nuclear fission a practical demonstration. For example, smoke detectors contain about 0.2 milligrams of americium-241, camping gas lanterns are coated with approximately 250 mg of thorium-232, and glow-in-the-dark gun sights contain around 1.2 micrograms of thorium-232. These materials are all radioactive and could potentially be combined to create a breeder reactor that uses neutrons emitted from one source to convert thorium-232 into the more radioactive uranium-233.

For a fusion reaction to occur, the temperature inside a fusion reactor must be hotter than the core of the sun – about 150 million °C (270 million °F) – Photo courtesy of Getty

David Hahn, a boy scout from Michigan, attempted this in 1994, but did not progress beyond the neutron generator stage before drawing attention from authorities. It is unlikely that his setup ever reached a stage where it could generate useful power.

Creating a functioning nuclear reactor from nuclear fission requires the ability to slow and control neutrons to maintain a self-sustaining fission reaction. Achieving this balance is challenging, especially in small reactors, and proper shielding and cooling are essential for safety.

While modern “microreactors” are available in the 5 megawatt range, they are still the size of a shipping container, making them unsuitable for small-scale setups.

Building a fusion reactor that uses an electric field to accelerate deuterium ions and fuse them into helium 3 is possible at home, resulting in a cold purple plasma. However, the energy required for the electric field exceeds the useful energy obtained from nuclear fusion, making it impractical as a reactor.

This article, by Tim Hurst from Sheffield, provides an answer to the question “Can I build a nuclear reactor in my shed?”

If you have any questions, please email us at: questions@sciencefocus.comor contact us on Facebook, Twitter, or Instagram (remember to include your name and location).

Explore more exciting science pages and fun facts on our website.

Read more:

Source: www.sciencefocus.com

Astronomers Uncover Magnetic Filaments Surrounding the Central Black Hole in Messier 77’s Accretion Disk

Posted on December 12, 2024 by Igor Mitreski

Messier 77 is a relatively nearby and well-known bright spiral galaxy with a supermassive black hole at its center.

Messier 77 concept by artist. It is characterized by its powerful black hole and accretion disk, as well as the polarized light of water masers located outside the Milky Way. Image credit: NSF / AUI / NRAO / S. Dagnello.

Messier 77 is a barred spiral galaxy located 62 million light-years away in the constellation Cetus.

Also known as NGC 1068, LEDA 10266, and Cetus A, it has an apparent magnitude of 9.6.

Messier 77 was discovered in 1780 by French astronomer Pierre Méchain, who initially identified it as a nebula. Méchain then relayed this discovery to his colleague, the French astronomer Charles Messier.

Messier believed that the extremely bright objects he saw were clusters of stars, but as technology advanced, their true status as a galaxy was recognized.

At 100,000 light-years in diameter, Messier 77 is one of the largest galaxies in the Messier catalog, and its gravity is enough to twist and distort other galaxies nearby.

It is also one of the closest galaxies to active galactic nuclei (AGNs).

These active galaxies are among the brightest objects in the universe, emitting light in many if not all wavelengths, from gamma rays and X-rays to microwaves and radio waves.

But Messier 77's accretion disk is hidden by a thick cloud of dust and gas, despite being a popular target for astronomers.

Several light-years in diameter, the outer accretion disk is dotted with hundreds of different water maser sources that have been hinting at deeper structures for decades.

Masers are clear beacons of electromagnetic radiation that shine at microwave or radio wavelengths. In radio astronomy, water masers, observed at a frequency of 22 GHz, are particularly useful because they can shine through many of the dusts and gases that block the wavelengths of light.

Bucknell University astronomer Jack Gallimore and his colleagues began observing Messier 77 with two goals in mind: astronomical mapping of the galaxy's radio continuum and measuring the polarization of water masers.

“Messier 77 is a bit of a VIP among active galaxies,” says Dr. CM Violette Impellizzeri, an astronomer at the Leiden Observatory.

“There's an accretion disk right next to the black hole, and it's unusually powerful. And because it's so close, it's been studied in great detail.”

But the study authors looked at Messier 77 in an entirely new way.

Their observations were recently upgraded High sensitivity array (HSA) consists of the Karl G. Jansky Very Large Array, the Very Long Baseline Array, and NSF's NRAO telescope at the Green Bank Telescope.

By measuring the water maser's polarization and the continuous radio emission from Messier 77, they reveal the compact radio source, now known as NGC 1068*, and the mysterious extended structure of the fainter emission. I created a map to

Mapping the astronomical distribution of galaxies and their water masers reveals that they are spread along structural filaments.

“These new observations reveal that the maser spot filaments are actually arranged like beads on a string,” Dr. Gallimore said.

“We were stunned to see that there was an apparent offset, or displacement angle, between the radio continuum, which describes the structure of the galaxy's core, and the position of the maser itself.”

“The configuration is unstable, so we're probably looking at a magnetically ejected source.”

Measuring the polarization of these water masers with HSA revealed significant evidence of a magnetic field.

“No one has ever seen polarization in water masers outside of our galaxy,” Dr. Gallimore said.

“Similar to the loop structures seen as prominences on the Sun's surface, the polarization patterns of these water masers clearly indicate that there is also a magnetic field at the root of these light-year-scale structures.”

“Looking at the filaments and making sure the polarization vector is perpendicular to the filaments is key to confirming that they are magnetically driven structures. It's exactly what you expected. It’s a thing.”

Previous studies of the region have suggested patterns, usually related to magnetic fields, but such conclusions were until recently beyond the scope of observational techniques.

The discovery reveals evidence for a compact central radio source (the galaxy's supermassive black hole), distinct polarization of water masers indicating structure within Messier 77's magnetic field, and spectacular extended signatures across the radio frequency continuum. It became.

Taken together, these findings indicate that magnetic fields are the underlying driving force for these phenomena.

However, many mysteries remain. For example, within the radio continuum map there is a diffuse, faint protrusion that the team has dubbed the foxtail foxtail, extending northward from the central region.

“When we set out on this, we said to ourselves, 'Let's really push the limits and see if we can get good continuum and polarization data,' and those goals were both It was a success,” Dr. Gallimore said.

“Using the NSF NRAO High Sensitivity Array, we detected the polarization of a water megamaser for the first time. We also created a very surprising continuum map, which we are still trying to understand.”

a paper The results will be explained today. Astrophysics Journal Letter.

_____

Jack F. Gallimore others. 2024. Discovery of polarized water vapor megamaser emission in molecular accretion disks. APJL 975, L9; doi: 10.3847/2041-8213/ad864f

Source: www.sci.news

Jawed vertebrate fossils dating back 400 million years discovered in Australia bring mystery to light

Posted on December 12, 2024 by Igor Mitreski

Palaeospondylus ganniwas a small, eel-like creature that lived during the mid-Devonian period, about 390 million years ago, and is among thousands of similarly preserved fossils from the Achanaras Quarry in Caithness, Scotland. is represented by. Radically different interpretations of its structure had assigned this species to almost all major jawless and jawed vertebrate groups. Paleontologists are currently identifying new and old species. spondylosis From the early Devonian period of Australia.

Palaeospondylus australisbrain cases and histological sections. Image credit: Barrow others., doi: 10.1093/nsr/nwae444.

First described in 1890, spondylosis It is a mysterious fish-like animal with a series of strange morphological features in the fossil record, including a lack of teeth and osteodermal bones.

Until now it was only known as Palaeospondylus ganni From the Middle Devonian Orcadian Basin in Scotland.

Initially interpreted as jawless vertebrates, they were soon classified into their own order and family.

Whereas the Scottish specimen was extremely compressed with all skeletal elements welded together, the new discovery spondylosisis located in a 400-million-year-old limestone in the Georgina Basin of western Queensland, central Australia, and is in a very different state of preservation as a 3D unfractured element.

“This is an amazing addition to Queensland's fossil record and is at the other end of the size scale of prehistoric giants like dinosaurs.” loetosaurus and Australotitan couperensis'' said Carol Barrow, a paleontologist at the Queensland Museum.

“What? Palaeospondylus australis Even more interesting is its relationship with similar species in northern Scotland. Palaeospondylus ganni”

The new fossil's honeycomb-like structure and complex internal features suggest the fish's early evolutionary importance.

The exact relationship is Palaeospondylus australis Although much remains unclear, as its features indicate that it retains many larval features, it is likely to be a distant relative of sharks.

This groundbreaking discovery not only enriches our understanding of ancient Australian ecosystems, but also highlights the global connectivity of early vertebrates across continents.

research Palaeospondylus australis It promises to uncover more mysteries about the evolution of jawed vertebrates.

“Discovery of a mysterious animal” spondylosis The early Devonian discovery in Australia indicates that this form is likely to have been distributed globally, given that Scotland and eastern Australia were then and now on opposite sides of the globe. “, the paleontologists said.

“New evidence regarding neurocranial features… spondylosis Adds important but contradictory information about that affinity. ”

“Until new and better evidence becomes available, spondylosis It is considered a pedunculate gnathostome, possibly a sister group to the cartilaginous fishes, and shows a mosaic of characters exhibited by both the osteoostia and some placoderms, as well as by the cartilaginous and teleost fishes. ”

of result appear in the diary National Science Review.

_____

Carol J. Barrow others. 3D brain box of early jawed vertebrates spondylosis From Australia. National Science Reviewpublished online on December 3, 2024. Doi: 10.1093/nsr/nwae444

Source: www.sci.news

Webb confirms Hubble’s calculations of distance

Posted on December 12, 2024 by Igor Mitreski

New observations by NASA/ESA/CSA’s James Webb Space Telescope confirm previous measurements by the NASA/ESA Hubble Space Telescope of the distances between nearby stars and galaxies, and confirm measurements of the universe’s mysterious expansion. Provide critical cross-checking to address discrepancies. This contradiction, known as the Hubble tension, remains unexplained by even the best cosmological models.

This artist’s impression shows the evolution of the universe, starting with the Big Bang on the left and continuing with the emergence of the Cosmic Microwave Background. The formation of the first stars ends the Dark Ages of the universe, followed by the formation of galaxies. Image credit: M. Weiss / Harvard-Smithsonian Center for Astrophysics.

“The discrepancy between the observed rate of expansion of the universe and the predictions of the Standard Model suggests that our understanding of the universe may be incomplete,” said Nobel laureate and Johns Hopkins University professor Adam Riess. “There is,” he said.

“Now that NASA’s two flagship telescopes are confirming each other’s discoveries, we must take this issue very seriously. It’s a challenge, but it’s a It’s also a great opportunity to learn more.”

The new research builds on Professor Rees’ Nobel Prize-winning discovery that the expansion of the universe is being accelerated by a mysterious dark energy that permeates the vast expanses of space between stars and galaxies.

The authors used the largest sample of Webb data collected during the first two years of the universe to test the Hubble telescope’s measure of the rate of expansion of the universe, a number known as the Hubble constant.

They used three different methods to measure the distance to the galaxy where the supernova occurred, using a method previously measured by the Hubble telescope and known to provide the most accurate “local” measurement of this number. We focused on the distance that is being

Observations from both telescopes were in close agreement, revealing that Hubble’s measurements were accurate and eliminating inaccuracies large enough to attribute the tension to Hubble’s errors.

Still, the Hubble constant remains a mystery. This is because measurements based on current telescopic observations of the universe produce higher values compared to projections made using the standard model of cosmology. The Standard Model is a widely accepted framework for how the universe works, calibrated with cosmic microwave background data. Weak radiation left over from the Big Bang.

The Standard Model Hubble constant is approximately 67-68 km/sec per megaparsec, but measurements based on telescope observations typically yield higher values of 70-76, with an average of 73 km/sec/megaparsec.

This discrepancy has puzzled cosmologists for more than a decade. A difference of 5 to 6 kilometers per second per megaparsec is too large to be explained solely by deficiencies in measurement and observation technology.

Webb’s new data eliminates significant bias in Hubble’s measurements, so the Hubble tension could be due to unknown factors or gaps in cosmologists’ understanding of physics that have yet to be discovered.

“Webb’s data represent the first high-definition view of the universe, greatly improving the signal-to-noise ratio of the measurements,” said Xiang Li, a graduate student at Johns Hopkins University. .

This image, taken with the Nicholas U. Mayall 4-meter telescope, shows the spiral galaxy Messier 106. Two dwarf galaxies (NGC 4248 in the lower right and UGC 7356 in the lower left) also appear in the image. Image credits: KPNO / NOIRLab / NSF / AURA / New Mexico State University MT Patterson / University of Alaska Anchorage TA Chancellor / M. Zamani & D. de Martin.

The astronomers used the known distance to the spiral galaxy Messier 106 (also known as M106 or NGC 4258) as a reference point to cover roughly one-third of Hubble’s total galaxy sample.

Despite the small dataset, they achieved impressive accuracy, showing less than 2% difference between measurements. This is much smaller than the approximately 8-9% size of the Hubble tension mismatch.

In addition to analyzing pulsating stars called Cepheid variable stars, the gold standard for measuring distances in the universe, they cross-checked measurements based on the brightest red giant stars in the same galaxy as carbon-rich stars. .

All galaxies observed by Webb with supernovae yielded a Hubble constant of 72.6 km per second per megaparsec. This is about the same as the 72.8 km per second per megaparsec that Hubble found for the very same galaxy.

“One possible explanation for the Hubble tension is that something was missing in our understanding of the early universe, such as a new component of matter that unexpectedly bombarded the universe after the Big Bang, nascent dark energy. I guess so,” Johns said. Mark Kamionkowski, a cosmologist at Hopkins University, was not involved in the study.

“And there are other ideas that might do the trick, like interesting dark matter properties, exotic particles, changing electron masses, or primordial magnetic fields. Theorists have a right to be pretty creative. It is.”

of result Published in astrophysical journal.

_____

Adam G. Reese others. 2024. JWST validates HST distance measurements: Supernova subsample selection explains differences in JWST estimates of local H0. APJ 977, 120; doi: 10.3847/1538-4357/ad8c21

Source: www.sci.news

The incidence of colorectal cancer is increasing in young populations globally

Posted on December 12, 2024 by Igor Mitreski

It’s not entirely clear why colorectal cancer is increasing among adults under 50

Steve Gschmeisner/Science Photo Library

SEI 232808754 — It’s not entirely clear why colorectal cancer is increasing among adults under 50

Steve Gschmeisner/Science Photo Library

The incidence of colorectal cancer in young adults is increasing worldwide, but this trend appears to be most prevalent in high-income countries.

Previous studies have shown that the incidence of bowel or colorectal cancer is increasing. Over the past few decades, it has increased in this age group in Western countries, including the United States, Canada, Australia, and the United Kingdom. This has led to speculation that Western lifestyles, including a diet high in meat and processed foods, may be to blame.

To better understand the extent of the problem, song hyunah Researchers from the American Cancer Society in Atlanta, Georgia, and colleagues looked at the incidence of colorectal cancer in 50 countries and territories around the world. They typically used the World Health Organization’s database to collect data on incidence rates from 1975 to 2017, although some countries started reporting this information several years after 1975. Ta.

The research team found that the incidence of colorectal cancer among people aged 25 to 49 is rising in 27 countries and territories. These also include non-Western countries such as Japan and less wealthy countries such as Turkey, raising the possibility that Western lifestyles are not solely behind this trend.

The increase is also unlikely to be related to improved screening tests, the researchers said in the paper, as most countries do not routinely test people for colorectal cancer until age 50.

However, all 27 countries and territories have high or very high scores on the United Nations Human Development Index, which is based on life expectancy, education level, and per capita income.

Additionally, all but six are considered high-income earners, according to the World Bank. Unlike most of the high-income countries studied, in these six countries, cases of colorectal cancer among older people are increasing at the same or faster rate than among younger people.

“I think there’s still evidence of trends that economic development and westernization of lifestyles are really having an impact,” he says. Andrew Chan The Harvard University researchers noted that many countries are adopting aspects of this lifestyle as their economies grow. for example, Japanese meat intake It increased more than seven times between 1961 and 2021.

“Having said that, I think we need to take into account the fact that there are probably other factors at play, such as environmental contaminants,” Chan says.

The researchers note that their study has several limitations, the most obvious being that countries in Africa, Asia and small islands were underrepresented. For example, only one African country was included: Uganda. Some countries did not have complete datasets. For example, India’s figures represent only 4 percent of the population.

Still, these findings could improve our understanding of how colorectal cancer incidence varies in many countries and help devise new ways to prevent the disease, Zhang said. say.

topic:

Source: www.newscientist.com