sciences energies environnement

 

traduction de 

Is the universe a fractal?

by Paul M. Sutter, Universe Today

L'univers est-il une fractale ?

par Paul M. Sutter, 

Universe Today

La formation de motifs symétriques et fractals complexes dans les flocons de neige illustre l'émergence dans un système physique. Crédit : Unsplash/CC0 Domaine Public

Depuis des décennies, les cosmologistes se demandent si la structure à grande échelle de l'univers est une fractale : si elle semble la même quelle que soit l'échelle. Et la réponse est : non, pas vraiment. Mais d'une certaine manière, oui. Regardez, c'est compliqué.

Notre univers est vaste et contient environ 2 000 milliards de galaxies. Ces galaxies ne sont pas dispersées au hasard, mais sont assemblées en une série de structures toujours plus grandes. Il y a les groupes, contenant au plus une douzaine de galaxies. Ensuite, il y a les amas, qui abritent un millier de galaxies et plus. Au-dessus d'eux se trouvent les superamas, qui se tordent et s'enroulent sur des millions d'années-lumière.

Est-ce la fin de l'histoire ?

Au milieu du XXe siècle, Benoît Mandelbrot a introduit le concept de fractales dans le grand public. Mandelbrot n'a pas inventé le concept de fractales (les mathématiciens étudiaient les modèles auto-similaires depuis des siècles), mais il a inventé le mot et inauguré notre étude moderne du concept. L'idée de base d'une fractale est que vous pouvez utiliser une seule formule mathématique pour définir une structure à toutes les échelles. En d'autres termes, vous pouvez zoomer et dézoomer sur une fractale et elle conserve toujours la même forme.

Les fractales apparaissent partout dans la nature, des branches d'un arbre aux bords d'un flocon de neige. Et Mandelbrot lui-même s'est demandé si l'univers était une fractale. Si, en zoomant, nous verrons les mêmes types de structures apparaître encore et encore.

Et d'une certaine manière, c'est ce que nous voyons : une hiérarchie de structures à des échelles de plus en plus grandes dans l'univers. Mais cette hiérarchie a une fin. À une certaine échelle, d'environ 300 millions d'années-lumière, le cosmos devient homogène, ce qui signifie qu'il n'y a pas de structures plus grandes et que l'univers est (à cette échelle) à peu près. le même d'un endroit à l'autre.

'univers n'est certainement pas une fractale, mais certaines parties de la toile cosmique ont néanmoins des propriétés fractales intéressantes. Par exemple, des amas de matière noire appelés « halos », qui abritent des galaxies et leurs amas, forment des structures et des sous-structures imbriquées, avec des halos contenant des sous-halos et des sous-sous-halos à l'intérieur de ceux-ci.

A l'inverse, les vides de notre univers ne sont pas entièrement vides. Ils contiennent quelques galaxies naines peu lumineuses... et ces quelques galaxies sont disposées dans une version subtile et peu lumineuse de la toile cosmique. Dans les simulations informatiques, les sous-vides au sein de cette structure contiennent également leurs propres toiles cosmiques effervescentes.

Ainsi, même si l'univers dans son ensemble n'est pas une fractale, et que l'idée de Mandelbrot n'a pas tenu la route, nous pouvons toujours trouver des fractales presque partout où nous regardons.

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COMMENTAIRES 

Cet article mérite il vote attention  ????

Que trouve-t-on dans l'univers aujourd'hui ?

Il est signé par Paul M. Sutter,   et son  travail 

Universe Today de

journaliste et écrivain ....peut etre trouvé sur internet 

xxxxx

 Alors maintenant pour mes lecteurs :Le mot "fractale" vient du latin "fractus" qui signifie "brisé". En effet, une fractale est un objet géométrique «infiniment morcelable''dont tous les détails sont observables à une échelle arbitrairement choisie. En zoomant sur une partie de la figure, on peut retrouver toute la figure, on dit qu'elle est auto similaire( reproduite rn changeant d 'échelle)

  Ce concept  a été  étudié pour la première fois par Blaise  Pascal  et développ" dans le célèbre chapitre ''les deux finis '' dans les ''Pensées''

Dans nos objets  se trouvent des cirons  qi contiennent eux memes d autre cirons plus petits    ....ETC 

XXXXXXX

La structure de l univers  a tres grande échelle   ne semble pas obéir  aux memes lois qu 'a l échelle quantique   .....Donc nous ne pouvons qualifier  notre univers comme fractal   ....

SCIRNCES ENERGIES ENVIRONNEMENT

 

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À :olivier hartmanshenn

lun. 30 déc. à 05:34

Dear olivier hartmanshenn,

Here is your customized Science X Newsletter for week 52:

	Ancient genomes provide final word in Indo-European linguistic origins A team of 91 researchers—including famed geneticist Eske Willerslev at the Lundbeck Foundation GeoGenetics Center, University of Copenhagen—has discovered a Bronze Age genetic divergence connected to eastern and western Mediterranean Indo-European language speakers.
	Can entangled particles communicate faster than light? Entanglement is perhaps one of the most confusing aspects of quantum mechanics. On its surface, entanglement allows particles to communicate over vast distances instantly, apparently violating the speed of light. But while entangled particles are connected, they don't necessarily share information between them.
	Thermodynamic model identifies how gold reaches Earth's surface A research team including a University of Michigan scientist has discovered a new gold-sulfur complex that helps researchers understand how gold deposits are formed.
	Ants prove superior to humans in group problem-solving maze experiment Anyone who has dealt with ants in the kitchen knows that ants are highly social creatures; it's rare to see one alone. Humans are social creatures too, even if some of us enjoy solitude. Ants and humans are also the only creatures in nature that consistently cooperate while transporting large loads that greatly exceed their own dimensions.
	Extremely rare baby mammoth found in Siberia Russian scientists on Monday showed off the remarkably well preserved remains of a baby mammoth found in the permafrost-covered region of Yakutia.
	Microbiome study finds bacteria in human gut rarely update their CRISPR defense systems Within the human digestive tract are trillions of bacteria from thousands of different species. These bacteria form communities that help digest food, fend off harmful microbes, and play many other roles in maintaining human health.
	Two endangered Florida predators found dead two days apart: 35 have been killed this year Two highly endangered Florida panthers were found dead from vehicle strikes only two days apart, closing out a particularly deadly year for the species.
	Numerical simulations show how the classical world might emerge from the many-worlds universes of quantum mechanics Students learning quantum mechanics are taught the Schrodinger equation and how to solve it to obtain a wave function. But a crucial step is skipped because it has puzzled scientists since the earliest days—how does the real, classical world emerge from, often, a large number of solutions for the wave functions?
	Is the universe a fractal? For decades, cosmologists have wondered if the large-scale structure of the universe is a fractal: if it looks the same no matter the scale. And the answer is: no, not really. But in some ways, yes. Look, it's complicated.
	Grapes of math: Ordinary fruit enhances performance of quantum sensors Macquarie University researchers have demonstrated how ordinary supermarket grapes can enhance the performance of quantum sensors, potentially leading to more efficient quantum technologies.
	Lifelong singles differ in personality traits and life satisfaction compared to partnered people, study reveals Although being married or in a long-term relationship is often seen as the norm, more people are staying single for life. But singlehood can bring economic and medical disadvantages, especially as people get older and may become more reliant on others.
	Geochemical surveys reveal ancient copper industry in King Solomon's mines did not pollute environment A new study from Tel Aviv University overturns prevailing scientific beliefs that King Solomon's Mines not only harmed the health of workers in the ancient copper industry but also pose risks to the health of modern residents living near the site.
	Walking pneumonia, the 'great masquerader,' on the rise in Washington This year, in addition to more familiar respiratory viruses like influenza, RSV and SARS-CoV-2, local health experts are also warning about a particular type of pneumonia infection.
	Octopuses are a new animal welfare frontier—what scientists know about consciousness in these unique creatures We named him Squirt—not because he was the smallest of the 16 cuttlefish in the pool, but because anyone with the audacity to scoop him into a separate tank to study him was likely to get soaked. Squirt had notoriously accurate aim.
	Two Earth-sized exoplanets orbiting nearby star detected An international team of astronomers has reported the discovery of two exoplanets orbiting a nearby star known as HD 101581. The newfound alien worlds are slightly smaller than Earth and orbit its host very closely. The discovery was detailed in a paper published Dec. 12 on the pre-print server arXiv.
	Newly discovered mechanism reveals NAD's role in aging and disease UiB researchers are behind a new discovery that tells us how associated neurodegenerative diseases might develop. At the center of this discovery stands a molecule called NAD, or nicotinamide adenine dinucleotide. The results have been published in Nature Metabolism.
	Migraine relief: New drug may start working right away A drug recently approved to prevent migraine may start working right away, according to a study published in the December 23, 2024, online issue of Neurology. The study looked at the drug atogepant, which is a calcitonin gene-related peptide (CGRP) receptor antagonist taken by mouth.
	Cooperation between two intruders moving side-by-side in granular media In bird colonies, schools of fish and cycling pelotons, significant interactions occur between individuals through the surrounding fluid. These interactions are well understood in fluids such as air and water, but what happens when objects move through something like sand? It turns out that similar interactions occur in granular materials—things like soil or sand—and they play a crucial role in everyday contexts. Think of plows cutting through farmland, animals burrowing underground, roots pushing through soil, or even robots exploring the surface of Mars.
	Fish-friendly dentistry: New method makes oral research non-lethal Can we examine the teeth of living fish and other vertebrates in detail, repeatedly over time, without harming them?
	Algebraic geometry offers fresh solution to data center energy inefficiency The manic pace of sharing, storing, securing, and serving data has a manic price—power consumption. To counter this, Virginia Tech mathematicians are leveraging algebraic geometry to target the inefficiencies of data centers. XXun. 30 déc. à 05:34 Cher olivier hartmanshenn, Voici votre newsletter Science X personnalisée pour la semaine 52 : Les génomes anciens fournissent le dernier mot sur les origines linguistiques indo-européennes Une équipe de 91 chercheurs, dont le célèbre généticien Eske Willerslev du Centre de géogénétique de la Fondation Lundbeck, Université de Copenhague, a découvert une divergence génétique de l'âge du bronze liée aux locuteurs de langues indo-européennes de l'est et de l'ouest de la Méditerranée. Les particules intriquées peuvent-elles communiquer plus vite que la lumière ? L'intrication est peut-être l'un des aspects les plus déroutants de la mécanique quantique. À sa surface, l'intrication permet aux particules de communiquer instantanément sur de vastes distances, violant apparemment la vitesse de la lumière. Mais si les particules intriquées sont connectées, elles ne partagent pas nécessairement d'informations entre elles. Un modèle thermodynamique identifie comment l'or atteint la surface de la Terre Une équipe de recherche comprenant un scientifique de l'Université du Michigan a découvert un nouveau complexe or-soufre qui aide les chercheurs à comprendre comment les gisements d'or se forment. Les fourmis se révèlent supérieures aux humains dans une expérience de résolution de problèmes en groupe dans un labyrinthe Quiconque a déjà eu affaire à des fourmis dans la cuisine sait que les fourmis sont des créatures très sociales ; il est rare d'en voir une seule. Les humains sont également des créatures sociales, même si certains d'entre nous aiment la solitude. Les fourmis et les humains sont également les seules créatures de la nature à coopérer constamment tout en transportant de lourdes charges qui dépassent largement leurs propres dimensions. Un bébé mammouth extrêmement rare découvert en Sibérie Des scientifiques russes ont montré lundi les restes remarquablement bien préservés d'un bébé mammouth découvert dans la région recouverte de pergélisol de Yakoutie. Une étude du microbiome révèle que les bactéries de l'intestin humain mettent rarement à jour leurs systèmes de défense CRISPR Dans le tube digestif humain se trouvent des milliards de bactéries de milliers d'espèces différentes. Ces bactéries forment des communautés qui aident à digérer les aliments, à repousser les microbes nocifs et jouent de nombreux autres rôles dans le maintien de la santé humaine. Deux prédateurs menacés de Floride retrouvés morts à deux jours d'intervalle : 35 ont été tués cette année Deux panthères de Floride, une espèce très menacée, ont été retrouvées mortes suite à des collisions avec des véhicules à seulement deux jours d'intervalle, clôturant une année particulièrement meurtrière pour l'espèce. Des simulations numériques montrent comment le monde classique pourrait émerger des univers à plusieurs mondes de la mécanique quantique Les étudiants qui apprennent la mécanique quantique apprennent l'équation de Schrödinger et comment la résoudre pour obtenir une fonction d'onde. Mais une étape cruciale est sautée car elle a intrigué les scientifiques depuis les premiers jours : comment le monde réel, classique, émerge-t-il d'un grand nombre de solutions pour les fonctions d'onde ? L'univers est-il une fractale ? Depuis des décennies, les cosmologistes se demandent si la structure à grande échelle de l'univers est une fractale : si elle semble la même quelle que soit l'échelle. Et la réponse est : non, pas vraiment. Mais d'une certaine manière, oui. Regardez, c'est compliqué. Les raisins des mathématiques : des fruits ordinaires améliorent les performances des capteurs quantiques Des chercheurs de l'Université Macquarie ont démontré comment les raisins ordinaires des supermarchés peuvent améliorer les performances des capteurs quantiques, ce qui pourrait conduire à des technologies quantiques plus efficaces. Les célibataires de longue date diffèrent en termes de traits de personnalité et de satisfaction de vie par rapport aux personnes en couple, révèle une étude Bien qu'être marié ou dans une relation à long terme soit souvent considéré comme la norme, de plus en plus de personnes restent célibataires toute leur vie. Mais le célibat peut entraîner des inconvénients économiques et médicaux, en particulier lorsque les personnes vieillissent et peuvent devenir plus dépendantes des autres. Des études géochimiques révèlent que l'ancienne industrie du cuivre dans les mines du roi Salomon n'a pas pollué l'environnement Une nouvelle étude de l'Université de Tel Aviv renverse les croyances scientifiques dominantes selon lesquelles les mines du roi Salomon ont non seulement nui à la santé des travailleurs de l'ancienne industrie du cuivre, mais présentent également des risques pour la santé des résidents modernes vivant à proximité du site. La pneumonie ambulante, le « grand masque », en hausse à Washington Cette année, en plus des virus respiratoires plus familiers comme la grippe, le VRS et le SARS-CoV-2, les experts locaux de la santé mettent également en garde contre un type particulier d'infection pneumonique. Les pieuvres sont une nouvelle frontière du bien-être animal : ce que les scientifiques savent de la conscience de ces créatures uniques Nous l'avons appelé Squirt, non pas parce qu'il était le plus petit des 16 seiches de la piscine, mais parce que quiconque avait l'audace de le ramasser dans un bac séparé pour l'étudier risquait d'être trempé. Squirt avait une visée notoirement précise. Deux exoplanètes de la taille de la Terre en orbite autour d'une étoile proche détectées Une équipe internationale d'astronomes a signalé la découverte de deux exoplanètes en orbite autour d'une étoile proche connue sous le nom de HD 101581. Les nouveaux mondes extraterrestres découverts sont légèrement plus petits que la Terre et gravitent autour de son hôte de très près. La découverte a été détaillée dans un article publié le 12 décembre sur le serveur de pré-impression arXiv. Un mécanisme récemment découvert révèle le rôle du N  ETC  OKXXXXXXXX

SCIENCES ENERGIES ENVIRONNEMENY

 

Je vaus donner  a mes lecteurs  une idfée  de ce que  je reçois chaque jour  de  Newsletters Science  X   . Mais je n ai pas comme eux  la struture  et l équipe  pour collecter résumer et sélectionner tout ce qui parait en permanence   . Mes lecteurs comprendront alors  pourquoi  je les remercie de m adresser chaque lundi la seur hyper selection que je vous traduit et commente  ...

And again :happy new year !!!!!

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• Dear olivier hartmanshenn,

  Here is your customized Science X Newsletter for December 27, 2024:

  Spotlight Stories Headlines

  Numerical simulations show how the classical world might emerge from the many-worlds universes of quantum mechanics

  Scientists use machine learning to develop an opener for a molecular can

  Study sheds more light on the nature of compact symmetric object DA 362

  Genetic analysis reveals kinship in ancient Moche sacrifice

  Sustained visual improvements in LHON patients treated with AAV gene therapy

  Light-driven method creates molecular fit that would otherwise be impossible

  Lifelong singles differ in personality traits and life satisfaction compared to partnered people, study reveals

  Study reveals macrophages' misunderstood role in lung fibrosis

  Hummingbird-inspired wings detect wind direction with 99% accuracy

  How monkeys recognize snakes so quickly

  Societal inequality linked to reduced brain health in aging and dementia

  Brain's 'tug-of-war': Choosing between classical and operant conditioning

  Researchers reveal changes in geometry and kinematics of the broad-line region in active galactic nuclei

  Detailed study reveals how cells coordinate to heal human wounds

  Astronauts face unique visual challenges at lunar south pole

  Nanotechnology news

  Light-driven method creates molecular fit that would otherwise be impossible Exploiting an ingenious combination of photochemical (i.e., light-induced) reactions and self-assembly processes, a team led by Prof. Alberto Credi of the University of Bologna has succeeded in inserting a filiform molecule into the cavity of a ring-shaped molecule, according to a high-energy geometry that is not possible at thermodynamic equilibrium. In other words, light makes it possible to create a molecular "fit" that would otherwise be inaccessible.

  Researchers develop high-performance heterojunction pn diodes A research team has developed high-performance diamond/ε-Ga2O3 heterojunction pn diodes based on ultrawide bandgap semiconductors, achieving breakdown voltages exceeding 3 kV. This work was published in Nano Letters.

  Physics news

  	Numerical simulations show how the classical world might emerge from the many-worlds universes of quantum mechanics Students learning quantum mechanics are taught the Schrodinger equation and how to solve it to obtain a wave function. But a crucial step is skipped because it has puzzled scientists since the earliest days—how does the real, classical world emerge from, often, a large number of solutions for the wave functions?
  	Scientists use machine learning to develop an opener for a molecular can In an era of medical care that is increasingly aiming at more targeted medication therapies, more individual therapies and more effective therapies, doctors and scientists want to be able to introduce molecules to the biological system to undertake specific actions.
  	Advancing unidirectional heat flow: The next era of quantum thermal diodes Heat management at the nanoscale has long been a cornerstone of advanced technological applications, ranging from high-performance electronics to quantum computing. Addressing this critical challenge, we have been deeply intrigued by the emerging field of thermotronics, which focuses on manipulating heat flux in ways analogous to how electronics control electric energy. Among its most promising advancements are quantum thermal diodes, which enable directional heat control, and quantum thermal transistors, which regulate heat flow with precision.
  	Spintronics memory innovation: A new perpendicular magnetized film Long gone are the days where all our data could fit on a two-megabyte floppy disk. In today's information-based society, the increasing volume of information being handled demands that we switch to memory options with the lowest power consumption and highest capacity possible.
  	AI model deciphers splashing drop patterns with high accuracy The impact of a drop on a solid surface is an important phenomenon that has various applications. Especially when the drop splashes, it can cause deterioration of printing and paint qualities, erosion, and propagation of airborne virus, among others. Therefore, it is important to observe and understand the characteristics of the splashing drops of different liquids.
  	Low-frequency photonic simulator breaks barriers A research team led by Prof. Li Chuanfeng from the University of Science and Technology of China (USTC) has achieved a breakthrough in quantum photonics. They developed an on-chip photonic simulator capable of simulating arbitrary-range coupled frequency lattices with gauge potential. This study was published in Physical Review Letters.
  	Researchers develop novel photopyroelectric tweezer for versatile manipulation Optical tweezers and related techniques provide extraordinary opportunities for research and applications in the physical, biological, and medical fields. However, certain requirements such as high-intensity laser beams, sophisticated electrode designs, additional electric sources, and low-conductive media, significantly impede their flexibility and adaptability, thus hindering their practical applications.
  	A new structure design enables a dual-function system for infrared camouflage and thermal management Combining metallic glass with the Berreman mode of epsilon-near-zero (ENZ) thin films achieves a dual-function system for infrared camouflage and thermal management within an identical wavelength region of the atmospheric window. In recent research, metallic glasses were selected for their tunable optical properties, providing adjustable emissivity for versatile thermal camouflage while maintaining effective thermal management.

  Earth news

  	Researchers discover role of absorptive aerosols in wintertime haze formation Aerosol light absorption plays a crucial role in regulating the heat balance between the atmosphere and Earth's surface. This happens through two main mechanisms: the aerosol direct effect, where aerosols absorb solar radiation, and the aerosol indirect effect, which involves aerosols acting as cloud condensation nuclei and ice nuclei.
  	'Dangerous new era': Climate change spurs disaster in 2024 From tiny and impoverished Mayotte to oil-rich behemoth Saudi Arabia, prosperous European cities to overcrowded slums in Africa, nowhere was spared the devastating impact of supercharged climate disasters in 2024.
  	Australian bushfire burns area the size of Singapore Australian firefighters said Friday they were fighting to control a bushfire racing through a national park that has consumed an area the size of Singapore.
  	Gaps identified in gravity wave simulations over Antarctica Spotting flaws is sometimes the first ripple in making waves of innovation.
  	How land use changes could boost China's carbon sequestration potential A team of researchers led by Professor Piao Shilong at the Institute of Carbon Neutrality of Peking University (PKU) has made significant advances in understanding how China's land-use changes—such as forest planting—can contribute to the country's efforts to reduce carbon emissions.
  	Rising temperatures threaten reefs—study pinpoints where conservation efforts are most needed New science from the Wildlife Conservation Society (WCS) has mapped coral reefs across the Western Indian Ocean, uncovering unexpected pockets of climate-resilience that could offer hope for conservation efforts in the region.
  	Maryland sues maker of Gore-Tex over pollution from toxic 'forever chemicals' Maryland is suing the company that produces the waterproof material Gore-Tex often used for raincoats and other outdoor gear, alleging its leaders kept using "forever chemicals" long after learning about serious health risks associated with them.
  	Oil leak in Peru tourist zone triggers 'environmental emergency' Peru has declared an "environmental emergency" after an oil spill that triggered a clean-up operation on a stretch of northern coastline popular with tourists.

  Astronomy and Space news

  	Study sheds more light on the nature of compact symmetric object DA 362 Indian astronomers have performed a multiwavelength study of a gamma-ray emitting compact symmetric object known as DA 362. Results of the study, presented in a research paper published December 17 on the pre-print server arXiv, yield more insights into the nature of this enigmatic object.
  	Researchers reveal changes in geometry and kinematics of the broad-line region in active galactic nuclei Dr. Feng Haicheng from the Yunnan Observatories of the Chinese Academy of Sciences, along with his collaborators, has made progress in studying the geometrical and kinematical evolution of the broad-line region (BLR) in active galactic nuclei (AGN). The study was published in The Astrophysical Journal.
  	Astronauts face unique visual challenges at lunar south pole Humans are returning to the moon—this time, to stay. Because our presence will be more permanent, NASA has selected a location that maximizes line-of-sight communication with Earth, solar visibility, and access to water ice: the Lunar South Pole (LSP).
  	NASA's Parker Solar Probe survives close brush with the sun's scorching surface NASA's Parker Solar Probe has successfully made the closest approach to the sun, the space agency confirmed Friday.

  Technology news

  	Hummingbird-inspired wings detect wind direction with 99% accuracy Bio-inspired wind sensing using strain sensors on flexible wings could revolutionize robotic flight control strategy. Researchers at the Institute of Science Tokyo have developed a method to detect wind direction with 99% accuracy using seven strain gauges on the flapping wing and a convolutional neural network model.
  	Move over Mercedes: Chinese cars grab Mexican market share The growing popularity of Chinese sport utility vehicles and pickup trucks has shaken up Mexico's luxury car market, hitting sales of traditionally dominant brands such as Mercedes-Benz and BMW.
  	OpenAI outlines plans to becoming for-profit company ChatGPT-maker OpenAI laid out plans Friday for a new corporate structure shifting away from control by a non-profit—an issue of contention for the artificial intelligence trailblazer.
  	Sport produces mountains of high-tech waste—researchers are finding new ways to recycle it In the early days of the modern Olympics and Paralympics, athletes competed using heavy, non-aerodynamic equipment. The record for throwing a javelin, for instance, has almost doubled since 1908, when the sport was introduced. Athletes have got better—but so has their equipment.
  	AI and robots pose new ethical challenges for society Artificial intelligence (AI) and AI-enabled robots are becoming a bigger part of our daily lives. Real-time, flexible interactions between humans and robots are no longer just science fiction. As robots become smarter and more human-like in both behavior and appearance, they are transforming from mere tools to potential partners and social entities.
  	Study explores microbial methods for hydrogen production from waste As the world grapples with rising energy consumption and escalating environmental crises, the need for sustainable energy solutions has never been more urgent. Microbial hydrogen production is emerging as a promising renewable energy pathway, offering a clean, high-energy-density alternative that can be sourced from a wide variety of feedstocks.
  	Montenegro to extradite crypto entrepreneur Do Kwon to US Montenegro announced on Friday that it would extradite South Korean cryptocurrency entrepreneur Do Kwon to the United States, following a year and a half of dizzying court rulings and subsequent reversals over his removal.
  	A comprehensive survey of federated transfer learning: Challenges, methods and applications Federated Learning (FL) has gained significant attention as a novel distributed machine learning paradigm that enables collaborative model training while preserving data privacy. However, traditional FL methods face challenges such as data heterogeneity, system heterogeneity, and labeled data scarcity.

  Biology news

  	How monkeys recognize snakes so quickly Dr. Nobuyuki Kawai from Nagoya University in Japan has found that the rapid detection of snakes by monkeys is because of the presence of snake scales as a visual cue. His findings highlight an evolutionary adaptation of primates to identify snakes based on specific visual characteristics.
  	Convergent evolution: stick and leaf insects share 20 body features A team of biologists in Montana and Germany has found that, regardless of type, those insects that express a protective stick- or leaf-like appearance all evolved the same basic body parts. In their study, published in the journal Proceedings of the National Academy of Sciences, Romain Boisseau, Douglas Emlen and Sven Bradler measured and compared characteristics from 1,359 stick insects covering 212 stick and leaf species and assessed the possibility of predicting evolutionary change.
  	Scientists uncover insights into neuron function by simultaneously measuring two key signals in living animals Researchers from Kyushu University have developed an innovative technique to non-invasively measure two key signals, membrane voltage and intracellular calcium levels, at the same time, in neurons of awake animals. This new method offers a more complete understanding of how neurons function, revealing that these two signals encode different information for sensory stimuli. The research was published in Communications Biology on September 16, 2024.
  	Conservationists call for fox-free zones to protect the Parma wallaby The creation of more fox-free safe havens and greater collaboration between government and landowners is needed to ensure the survival of a species of wallaby, an expert from The Australian National University (ANU) argues.
  	Cats can get sick with bird flu. Here's how to protect them The death of an Oregon house cat and a pet food recall are raising questions about the ongoing outbreak of bird flu and how people can protect their pets.
  	Research unveils new bacteriophage more effective than similar species Bacteria are becoming increasingly resistant to antibiotics. This "race" can lead to a situation where antibiotics will stop suppressing pathogenic bacteria. Bacteriophages, natural "predators" of bacteria, are considered one of the alternatives.
  	How do you 'grow' an endangered starfish? Scientists are finding out For the last decade, California's offshore seafloors have been missing a massive, colorful predator that keeps kelp-munching sea urchins in check.
  	Bird flu kills 20 big cats in Washington state sanctuary Four cougars. Four bobcats. Two lynx. Even a Bengal tiger.
  	Study finds genetic and environmental factors neutralize bacterial growth Researchers at the University of Tsukuba have conducted a high-throughput growth assay and used machine learning to address the genetic and environmental interplay of bacterial growth.
  	Mayotte faces environment, biodiversity crisis after cyclone Mayotte has changed beyond recognition since a cyclone devastated the Indian Ocean territory, sparking an environment and biodiversity crisis that could last for a decade or more, scientists say.
  	Two endangered Florida predators found dead two days apart: 35 have been killed this year Two highly endangered Florida panthers were found dead from vehicle strikes only two days apart, closing out a particularly deadly year for the species.
  	Roasting chestnuts, recycling walnuts: turning festive treats into sustainable new materials EU researchers are exploring how to make strong and sustainable new materials from hard-to-crack nutshells.

  Medicine and Health news

  	Sustained visual improvements in LHON patients treated with AAV gene therapy A multinational study led by the LHON Study Group has revealed sustained visual improvements and a favorable safety profile five years following lenadogene nolparvovec gene therapy in patients with Leber hereditary optic neuropathy (LHON) caused by the MT-ND4 gene mutation.
  	Lifelong singles differ in personality traits and life satisfaction compared to partnered people, study reveals Although being married or in a long-term relationship is often seen as the norm, more people are staying single for life. But singlehood can bring economic and medical disadvantages, especially as people get older and may become more reliant on others.
  	Study reveals macrophages' misunderstood role in lung fibrosis Researchers at National Jewish Health and colleagues have completed the first study comparing lung macrophages in multiple models of lung injury. The research indicates that macrophages previously described as "pro-fibrotic" are insufficient to cause fibrosis on their own, opening the door to research that can help advance the understanding of how macrophage programming can help or hinder lung repair.
  	Societal inequality linked to reduced brain health in aging and dementia Researchers from Trinity College Dublin have collaborated with international partners to explore if societal inequality affects the brain.
  	Brain's 'tug-of-war': Choosing between classical and operant conditioning A study from Tel Aviv University could reshape our scientific understanding of how humans learn and form memories, particularly through classical and operant conditioning.
  	Detailed study reveals how cells coordinate to heal human wounds A new study from Karolinska Institutet maps the cellular and molecular dynamics of human wound healing in exceptional detail. The study was published in Cell Stem Cell.
  	A public health emergency is waiting at the bottom of the antibiotic resistance cliff The rise of antibiotic-resistant bacteria could lead to a catastrophic rise in infection-related deaths, according to new research led by Northern Arizona University.
  	Cooking garlic and onions at high heat can form trans fats, study finds Trans-fatty acids (TFA) are a major cause of cardiovascular diseases. These harmful fats can accumulate along artery walls, restricting blood flow and increasing the risk of heart attacks. According to the World Health Organization (WHO), TFAs are responsible for over 278,000 annual deaths worldwide, and it recommends that TFA consumption should be limited to less than 1% of daily energy intake.
  	FDA approves first generic liraglutide once-daily injection The U.S. Food and Drug Administration has approved the first generic referencing Victoza (liraglutide; Hikma Pharmaceuticals), a glucagon-like peptide-1 (GLP-1) receptor agonist indicated to improve glycemic control in adults and pediatric patients aged 10 years and older with type 2 diabetes.
  	Black children suspected of experiencing child abuse at higher rates, suggests study Black children are suspected to have experienced child abuse at higher rates than children of other racial and ethnic backgrounds, according to a study published online Dec. 18 in JAMA Network Open.
  	New laser technology improves stent effectiveness in vascular treatments A Korea Institute of Science and Technology (KIST) research team has developed a novel stent surface treatment technology using laser patterning. This technology promotes endothelial cell growth while inhibiting smooth muscle cell dedifferentiation in blood vessels.
  	What to know about infectious diseases during this holiday season It's that time of year, when families and friends come together to share their holiday cheer and a few circulating pathogens.
  	Exploring options to keep costs in focus when buying new glasses Now that the Federal Trade Commission is doubling-down on its rule requiring eye doctors to provide their patients' prescriptions after eye exams, consumers are encountering more options for their purchases than just those in their doctor's office lobby.
  	New genetic mutation found to suppress cancer growth UT Southwestern Medical Center researchers have identified a genetic mutation that slows the growth of melanoma and potentially other cancers by harnessing the power of the immune system. Their findings, published in the Journal of Experimental Medicine, could lead to new treatments that improve outcomes from existing cancer immunotherapies.
  	Q&A: How circadian rhythms have been implicated in diseases from dementia to cancer In this season of short days and long winter nights, it's easy to feel out of sorts. Those who suffer from seasonal affective disorder, a form of depression that's closely linked to the circadian rhythms that govern our sleep cycles, know this all too well. But those same rhythms, which are themselves governed by biological clocks, can affect much more than mood and sleep.
  	Monitoring long-term cardiac activity with contactless radio frequency signals A research team led by Prof. Chen Yan at the University of Science and Technology of China (USTC) has taken a leap forward in cardiovascular health monitoring. They have developed a non-invasive radio frequency (RF)-based system capable of monitoring heart rate variability (HRV) with clinical-grade accuracy over extended periods.
  	Proposed FDA rule targets asbestos in talc cosmetic products The U.S. Food and Drug Administration (FDA) has proposed a new rule to require standardized testing of talc-containing cosmetics for asbestos, a known carcinogen linked to serious illnesses such as lung and ovarian cancers.
  	Digital health care consultations not enough for safe assessment of tonsillitis Tonsillitis is a common reason for visits to the doctor and prescriptions of antibiotics in primary care. To determine whether a patient needs antibiotics, doctors use the so-called Centor Criteria for tonsillitis. The criteria include fever, tender and swollen lymph nodes in the angles of the jaw and inspection of the tonsils.
  	New bird flu mutation discovered in US as cat infections cause alarm The ongoing spread of bird flu in the United States has alarmed experts—not just because of human cases causing severe illness, but also due to troubling new instances of infections in cats.
  	Money, gun violence, hate crimes: Poll reveals top worries at the end of 2024 Should you cut back on doom scrolling in 2025? Worries about money, gun violence and hate crimes ranked high among many people's lists of worries at the end of 2024, according to a poll that is part of American Psychiatric Association (APA) Healthy Minds Monthly opinion poll series. The survey included 2200 U.S. adults.
  	Most families exclude food allergens from their household Most families choose to exclude food allergens from their households, and those that do report more food allergy (FA)-related concerns, according to a research letter published online Dec. 27 in JAMA Network Open.
  	U.S. health care spending reached $4.9 trillion in 2023 Health care spending in the United States reached $4.9 trillion and increased 7.5 percent in 2023, according to a study published online Dec. 18 in Health Affairs.
  	Bidirectional association found between rheumatoid arthritis, COPD There is a bidirectional association between rheumatoid arthritis (RA) and chronic obstructive pulmonary disease (COPD), according to a review published online Dec. 1 in Frontiers in Immunology.
  	Influenza vaccine effective against severe illness in children Influenza vaccine is effective for preventing severe influenza illness among children, according to a study published online Dec. 27 in JAMA Network Open.
  	Children have various symptoms within five years before MS diagnosis Children and adolescents with multiple sclerosis (MS) have a range of symptoms, signs, and diagnoses within five years before diagnosis, according to a study published online Dec. 27 in JAMA Network Open.
  	Reporting of human adenoviruses has declined since COVID-19 Reporting of human adenovirus (HAdV) types decreased since the COVID-19 pandemic, according to research published in the Dec. 19 issue of the U.S. Centers for Disease Control and Prevention Morbidity and Mortality Weekly Report.
  	FDA approves Ryoncil for steroid-refractory acute graft-versus-host after allo-HSCT The allogeneic bone marrow-derived mesenchymal stromal cell (MSC) therapy Ryoncil (remestemcel-L-rknd) has been approved for treatment for steroid-refractory acute graft-versus-host disease (SR-aGVHD) in pediatric patients aged 2 months or older, according to a press release from the U.S. Food and Drug Administration.
  	Disparities seen in firearm, motor vehicle crash fatalities in U.S. youth Disparities exist in firearm and motor vehicle crash (MVC) fatalities among youth in the United States, according to a study published online Dec. 23 in JAMA Pediatrics.
  	Could a maverick raw milk farmer from California help RFK Jr. shape US health policy? As Mark McAfee—the maverick leader of California's largest raw milk dairy—works on getting his Fresno County dairy out of bird flu quarantine, his name has surfaced as a possible advisor for the Food and Drug Administration on shaping raw milk policy in the United States.
  	He went in for a colonoscopy: The hospital charged $19,000 for two Tom Contos is an avid runner. When he started experiencing rectal bleeding in March, he thought exercise could be the cause and tried to ignore it. But he became increasingly worried when the bleeding continued for weeks.
  	Pediatrician suggests eight parenting goals to start the new year strong New Year's resolutions are typically sweeping and grand. But you can often reap the biggest rewards by building off strengths already in place. Helping to make your family safer, stronger and more harmonious in the coming year may not require a complete overhaul, but rather a few strategic tweaks.
  	Colorado stops water testing at state lab amid investigation into manipulated data The Colorado Department of Public Health and Environment has suspended a second chemist and stopped water testing at the state laboratory amid a state investigation into manipulated data.
  	University of Washington plans to launch mental health crisis response team this spring Starting this spring, the University of Washington will try a new approach to helping students and employees in mental health crises, based on a philosophy that's become increasingly mainstream: Mental health professionals are better equipped than police to respond to some emergencies.
  	Boston to distribute Narcan via vending machines, kiosks to prevent opioid overdoses Boston will have four vending machines and eight indoor kiosks distributing life-saving Narcan and other harm reduction supplies in another step toward preventing overdose deaths, Mayor Michelle Wu and the Boston Public Health Commission announced.
  	Why it's important to update adult vaccinations for a new year Personal health is often among the top New Year's resolutions each January. Beyond diet and exercise, Dr. John Presutti, a Mayo Clinic family medicine physician, says the start of a new year is a good calendar reminder to update adult vaccinations.

  Other Sciences news

  	Genetic analysis reveals kinship in ancient Moche sacrifice Harvard University-led researchers investigated an elite Moche burial group at Huaca Cao Viejo, uncovering new details on kin-based status within Moche society. The evidence centers on four generations of a family dated to approximately 500 CE, with genetic data connecting the Señora de Cao to a sibling, a grandparent, and two sacrificed juveniles.
  	Researchers examine corporate social responsibility's impact on global online shopping Online shopping is revolutionizing how we access and purchase products from international markets. Despite this growth, many consumers remain hesitant to purchase goods from foreign companies due to trust issues, cultural differences, and concerns about unfamiliar products.
  	Study shows that 11- to 12-year-olds use smartphones mainly to talk to family and friends The moment a child gets his/her first mobile phone as a gift is a source of worry for many parents. Concern about the risks associated with smartphone use has led to more and more initiatives trying to delay that moment.
  	Boardroom diversity affects carbon emissions—but not in the way you think Extreme weather and record-breaking heat waves are becoming the new normal. Most people have begun to accept the seriousness of grim reports from the UN's climate panel and that climate change is a result of human activity.
  	Migration intentions: The interactive roles of affective polarization and dyadic political attitudes The 2019 Anti-Extradition Law Amendment Bill (Anti-ELAB) Movement triggered a dramatic shift in Hong Kong's political landscape. In 2020, the Chinese central government enacted the National Security Law to tighten its control over Hong Kong and reformed the electoral system, imposing stricter candidate qualifications.

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