| عدد زوار مدونات الصدح |  |
|  | |
| المواضيع |
|---|
انتقل الى الصفحة :  1 ... 32 ... 60, 61, 62 ... 64 ... 68 |
 Since the dawn of the space age, unmanned spacecraft have flownblind with little or no ability to make autonomous decisions based onthe content of the data they collect. The Autonomous SciencecraftExperiment (ASE) is operating onboard the Earth Observing-1mission since 2003.The ASE software uses onboard continuous planning, robust task andgoal-based execution, and onboard machine learning... |
EVIDENCE OF A PLANET IN FORMATION? ASTROPHYSICISTS OBSERVE A CIRCUMSTELLAR DISK WITH TELL-TALE SIGNS OF PLANET FORMATION Coronagraphic image of the polarized light around the star AB Aurigae, showing the distribution of dust in the inner part of a complex disk of material around this star. The shaded middle region is covered to block out light from the star. The inset... |
CLIMATE CHANGE HASTENS EXTINCTION AS MALAGASY REPTILES AND AMPHIBIANS MOVE UPHILL ACCORDING TO AMERICAN MUSEUM OF NATURAL HISTORY SCIENTIST Calumma tsaratananensis, one of the example species endemic to the summit region of Tsaratanana.Credit: AMNHNew research from the American Museum of Natural History provides the first detailed study showing that global warming forces species to move up tropical... |
New Research from the American Museum of Natural History Highlights Polar Bears' Ability to Adapt to a Changing Arctic A young polar bear, Ursus maritimusCredit: Patricia Rockwell, Hunter College BiologyAs polar bears adapt to a warming Arctic—a frozen seascape that cleaves earlier each spring—they may find relief in an unlikely source: snow goose... |
COOKIE CUTTER IN THE SKYFor the First Time, Scientists See that Material Flowing into Known Black Holes Looks Similar, No Matter How Massive the Black Hole The infrared glow surrounding a black holeCredit: Chris ReynoldsBlack holes can now be thought of as donut holes. The shape of material around black holes has been seen for... |
FISH OUT OF WATERNew Species of Climbing Fish from Remote Venezuela Shakes the Catfish Family Tree New catfish species Lithogenes wahari found in the Río CuaoPhoto: S. Schaefer/AMNH. A new species of fish from tropical South America is confirming suspected roots to the loricariid catfish family tree. Lithogenes wahari... |
MOVE OVER SPONGESNew Evidence from the Sackler Institute for Comparative Genomics Confirms Placozoans Are the Closest Living Surrogate to the Ancestor of All Animals Trichoplax Credit: B. SchierwaterA new and comprehensive analysis confirms that the evolutionary relationships among animals are not as simple as previously thought.... |
http://www.amnh.org/science/papers/triceratops.phpWAS TRICERATOPS A SOCIAL ANIMAL? Yes, According to a New Fossil Discovery in Montana's Homer Site  A juvenile Triceratops uncovered in Montana. (Click to see a larger image.) S. Brusatte/AMNH Until now,... |
BE A BEE WATCHER
THE GREAT POLLINATOR PROJECT RECRUITS CITIZEN SCIENTISTS FOR THE THIRD YEAR “It was cool to see how bees used flowers in characteristic ways.”
“I enjoyed contributing to science.”
“I was happy that I became less afraid of bees.”  Members of the green sweat bee genera Agapostemon—like this photographed in New York City—range throughout... |
MOTHS CLOAKED IN COLOR
Reexamination of Parallel Evolution in Diurnal Neotropical Moths Appears in Bulletin of The American Museum of Natural History Travelers to the neotropics—the tropical lands of the Americas—might be forgiven for thinking that all of the colorful insects flittering over sunny puddles or among dense forest understory are butterflies. In fact, many are not. Some are moths that have reinvented themselves as butterflies, converging on the daytime niche typically dominated by their less hairy relatives. Now, a new...
|
BARCODING ENDANGERED SEA TURTLES
Demonstrating that Short Genetic Sequences Identify Migratory Marine SpeciesConservation geneticists who study sea turtles have a new tool to help track this highly migratory and endangered group of marine animals: DNA barcodes. DNA barcodes are short genetic sequences that efficiently distinguish species from each other–even if the samples from which the DNA is extracted are minute or degraded. Now, a recently published research paper by scientists from the American Museum of Natural History and the University...
|
GETTING A LEG UP ON WHALE AND DOLPHIN EVOLUTION
NEW COMPREHENSIVE ANALYSIS SHEDS LIGHT ON THE ORIGIN OF CETACEANSWhen the ancestors of living cetaceans—whales, dolphins and porpoises—first dipped their toes into water, a series of evolutionary changes were sparked that ultimately nestled these swimming mammals into the larger hoofed animal group. But what happened first, a change from a plant-based diet to a carnivorous diet, or the loss of their ability to walk? A new paper published this week in PLoS One resolves this debate using a massive...
|
BIZARRE NEW HORNED TYRANNOSAUR FROM ASIA DESCRIBED
CARNIVOROUS BUT SMALLER T. REX RELATIVE SHARED ENVIRONMENT WITH LARGER COUSINSNow, just a few weeks after tiny, early Raptorex kriegsteini was unveiled, a new wrench has been thrown into the family tree of the tyrannosaurs. The new Alioramus altai — a horned, long-snouted, gracile cousin of Tyrannosaurus rex — shared the same environment with larger, predatory relatives. A paper published this week in the Proceedings of the National Academy of Sciences describes this exceptionally...
|
DIRTY STARS MAKE GOOD SOLAR SYSTEM HOSTS
TIPPING POINT IN PLANET FORMATION FOUND BY NEW SIMULATIONSSome stars are lonely behemoths, with no surrounding planets or asteroids, while others sport a skirt of attendant planetary bodies. New research published this week in The Astrophysical Journal Letters explains why the composition of the stars often indicates whether their light shines into deep space, or whether a small fraction shines onto orbiting planets. When a star forms, collapsing from a dense cloud into a luminous ball, it...
|
A FAINT STAR ORBITING THE BIG DIPPER'S ALCOR DISCOVERED
PROJECT 1640 SEES THE UNKNOWN USING A NOVEL TECHNIQUE KNOWN TO GALILEONext time you spy the Big Dipper, keep in mind that there is another star, invisible to the unaided eye, contributing to this constellation. According to a new paper soon to be published in The Astrophysical Journal, one of the stars that makes the bend in the ladle's handle, Alcor, has a smaller red dwarf companion. Newly discovered Alcor B orbits its larger sibling and was caught in the act with an innovative...
|
LATE-SURVIVING MEGAFAUNA EXPOSED BY ANCIENT DNA IN FROZEN SOIL
EXTINCT MAMMOTH AND HORSE LINGERED THOUSANDS OF YEARS LONGER THAN EXPECTEDExtinct woolly mammoths and ancient American horses may have been grazing the North American steppe for several thousand years longer than previously thought. After plucking ancient DNA from frozen soil in central Alaska, a team of researchers used cutting-edge techniques to uncover "genetic fossils" of both species locked in permafrost samples dated to between 7,600 and 10,500 calendar years. This...
|
SCIENTIFICALLY RENDERING THE KNOWN UNIVERSE FOR ALL TO SEE
NEW VIDEO GOES VIRALDecember 18, 2009 New York City — In three days, over 150,000 people have viewed The Known Universe, a new film produced by the American Museum of Natural History that is part of the new exhibition Visions... |
HOW EARTH SURVIVED BIRTH
NEW SIMULATION PRESENTED AT ASTRONOMY MEETING
REVEALS PLANET MIGRATION PREVENTS PLUNGE INTO SUN For the last 20 years, the best models of planet formation—or how planets grow from dust in a gas disk—have contradicted the very existence of Earth. These models assumed locally constant temperatures within a disk, and the planets plunge into the Sun. Now, new simulations from researchers at the American Museum of Natural History and the University of Cambridge show that variations in temperature can lead to regions of outward...
|
GRIZZLY BEARS MOVE INTO POLAR BEAR HABITAT IN MANITOBA, CANADA
COMPETITION FROM OTHER BEARS MAY THREATEN A POLAR BEAR POPULATIONBiologists affiliated with the American Museum of Natural History and City College of the City University of New York have found that grizzly bears are roaming into what was traditionally thought of as polar bear habitat—and into the Canadian province of Manitoba, where they are officially listed as extirpated. The preliminary data was recently published in Canadian Field Naturalist and shows that sightings...
|
PHYLOGENETIC ANALYSIS OF MEXICAN CAVE SCORPIONS SUGGESTS
ADAPTATION TO CAVES IS REVERSIBLE
NEW EVIDENCE THAT SPECIALIZED ADAPTATIONS ARE NOT EVOLUTIONARY DEAD ENDS Blind scorpions that live in the stygian depths of caves are throwing light on a long-held assumption that specialized adaptations are irreversible evolutionary dead-ends. According to a new phylogenetic analysis of the family Typhlochactidae, scorpions currently living closer to the surface (under stones and in leaf litter) evolved independently on more than one occasion from...
|
SIMULATIONS SOLVE A 20-YEAR-OLD RIDDLE ABOUT
WHY NEBULAE AROUND MASSSIVE STARS DON'T DISAPPEAR
NEBULAE AROUND STARS WITH GIRTH FLICKER LIKE CANDLESThe birth of the most massive stars—those ten to a hundred times the mass of the Sun—has posed an astrophysical riddle for decades. Massive stars are dense enough to fuse hydrogen while they're still gathering material from the gas cloud, so it was a mystery why their brilliant radiation does not heat the infalling gas and blow it away. New simulations by researchers affiliated with the University...
|
HARNESSING THE WEB AND SUPERCOMPUTERS
TO TRACK PATHOGENS AS THEY EVOLVE
NEW TOOL TO STOP DISEASE OUTBREAKS AND INFORM NATIONAL SECURITYPathogens can now be easily tracked in time and space as they evolve, an advance that could revolutionize both public health and inform national security in the fight against infectious diseases. Developed by researchers that include scientists at the American Museum of Natural History, Supramap is a new, powerful,... |
THE NEW T. REX: A LEECH WITH AN AFFINITY FOR NOSES
NEW GENUS AND SPECIES OF LEECH DISCOVERED BY DOCTORS IN AMAZONIAN PERÚThe new T. rex has ferociously large teeth lining a single jaw. But its length is less than 2 inches. Tyrannobdella rex, which means tyrant leech king, is a new species of blood sucker that lives in the remote parts of the Upper Amazon. Although its regular host remains unknown, it was discovered three years ago in Perú when a 44.5 millimeter leech was plucked from the nose of a girl who had recently been bathing...
|
MERCURY IS HIGHER IN SOME TUNA SPECIES
ACCORDING TO DNA BARCODING
NEW RESEARCH PROVIDES INSIGHT INTO HEALTHIER CONSUMPTION OF SUSHINew research showing that that mercury levels are higher in some species of tuna could help consumers minimize their consumption of the silvery metal in their sushi and provide a powerful new tool for regulatory organizations. The new research—combining DNA barcoding at the American Museum of Natural History with analysis of mercury content at Rutgers University—is published in Biology Letters early...
|
SCIENTISTS DESCRIBE TWO NEW SPECIES OF FISH
FROM AREA ENGULFED BY OIL SPILL
NEW SPECIES OF PANCAKE BATFISHES DISCOVERED IN THE GULF OF MEXICONew research published in the Journal of Fish Biology describes two new species of pancake batfishes (Halieutichthys intermedius and H. bispinosus) and re-describes another (H. aculeatus), all of which live in waters either partially or fully encompassed by the recent oil spill. The research, partly the work of American Museum of Natural History scientist John...
| |
| | عدد المتصفحين الحاليين للمنتدى: لا أحد
| | المشرف: | المشرف العام | | صلاحيات هذا المنتدى: | تستطيع وضع مواضيع جديدة في هذا المنتدى
تستطيع الرد على المواضيع في هذا المنتدى
| |
| عدد المتصفحين الحاليين للمنتدى: لا أحد
| |
| |  مساهمات جديدة
![مساهمات جديدة [ موضوع شعبي ]](https://2img.net/i/fa/subsilver/folder_new_hot.gif) مساهمات جديدة [ موضوع شعبي ]
![مساهمات جديدة [ موضوع مقفل]](https://2img.net/i/fa/subsilver/folder_lock_new.gif) مساهمات جديدة [ موضوع مقفل] |  لا مساهمات جديدة
![لا مساهمات جديدة [موضوع شعبي ]](https://2img.net/i/fa/subsilver/folder_hot.gif) لا مساهمات جديدة [موضوع شعبي ]
![لا مساهمات جديدة [موضوع مقفل]](https://2img.net/i/fa/subsilver/folder_lock.gif) لا مساهمات جديدة [موضوع مقفل] |  اعلان
إعلان عام
 مثبت
|
|
| | المواضيع الأخيرة | » تتلبالثلاثاء أبريل 16, 2024 2:34 pm من طرف سميح القاسم» ابداع من عالم انتهىالسبت أبريل 06, 2024 4:53 am من طرف سميح القاسم» تولانيالجمعة ديسمبر 29, 2023 3:53 pm من طرف سميح القاسم» الزلزال تذكير بمكانة الانسان في الطبيعةالسبت سبتمبر 09, 2023 8:21 am من طرف سميح القاسم» زلزال المغرب ابان عن غياب الدولة المخزنيةالسبت سبتمبر 09, 2023 6:45 am من طرف سميح القاسم» زلزال المغرب ابان عن غياب الدولة المخزنيةالسبت سبتمبر 09, 2023 4:32 am من طرف سميح القاسم» القضاء المغربي فاسد وغير مستقل الخميس سبتمبر 07, 2023 9:05 am من طرف سميح القاسم» طبيعة دولة دينية مقنعةالنظام السياسي في المغرب. دولة دينية مقنعةالخميس سبتمبر 07, 2023 4:25 am من طرف سميح القاسم» النظام السياسي المغربي وافاقهالأربعاء سبتمبر 06, 2023 3:56 pm من طرف سميح القاسم» الغزو ا٪روسي لاوكرانيا نزعة توسعية ديكتاتوريةالأربعاء سبتمبر 06, 2023 11:25 am من طرف سميح القاسم» المغرب وضع سياسي متوتر واحتقان شعبي صامتالأربعاء سبتمبر 06, 2023 6:11 am من طرف سميح القاسم» ورشة نص سناريو لليلم قصير الكابوس لكاتبه لععليليس فالإثنين مارس 28, 2022 4:19 am من طرف سميح القاسم» لا تستنع الو الفاشلينالخميس يوليو 08, 2021 6:39 pm من طرف سميح القاسم» لا تستمع الى الفاشلينالجمعة يوليو 02, 2021 6:37 pm من طرف سميح القاسم» ع بنعبد العالي الحداثة ومسألة القطيعةالأحد يونيو 27, 2021 6:50 pm من طرف بن عبد الله» بقايا استعباد قديمةالأحد يونيو 27, 2021 6:49 pm من طرف بن عبد الله» شفرات الحياة الفن ومعنى الانسانيةالأحد يونيو 27, 2021 6:47 pm من طرف بن عبد الله» ريتا فرج: المنظومة البطريركية الدينية تدافع بقوة عن نفسها وتتبنى لغة متوترة تجاه النسويات المجدداتالجمعة يونيو 25, 2021 12:33 pm من طرف بن عبد الله» كيف يكونوايمان الاحرار الجمعة يونيو 25, 2021 12:31 pm من طرف بن عبد الله» فالتر بنيامين: الرأسماليّة بوصفها ديناًالجمعة يونيو 25, 2021 12:28 pm من طرف بن عبد الله» فريديريك غرو: فوكو وســــــؤال العنفالجمعة يونيو 25, 2021 12:26 pm من طرف بن عبد الله» الاسقاط النفسي والزمن 7 أيام مضت دراسات وأبحاث, علي محمد اليوسف, مفاهيم 0 علي محمد اليوسف علي محمد اليوسف لتكن البداية من منطلق التساؤل هل يمكننا اسقاط رغائب النفس على السيرورة الحركية للزمن في الزاميه التنفيذ الاستجابي تحقيق تلك الرغائب النفسية حتالجمعة يونيو 25, 2021 12:21 pm من طرف بن عبد الله» حفلة التيس: قراءة في فلسفة الطغيان وتهافت الدولة العسكريةالجمعة يونيو 25, 2021 12:18 pm من طرف بن عبد الله» برجسون وباشلار: ميتافيزيقا الزمن والنفسالجمعة يونيو 25, 2021 12:15 pm من طرف بن عبد الله» إجابة عن السؤال: ماهو التنوير؟الجمعة يونيو 25, 2021 12:05 pm من طرف بن عبد الله» سهام الدبابي الميساوي: أهمية ومنهج دراسة الحياة اليوميةالخميس يونيو 24, 2021 1:08 pm من طرف بن عبد الله» حوار مشترك مع الفيلسوف أرشيبيكي والفيلسوفة سيلا بنحبيب: تقييد الديمقراطياتالخميس يونيو 24, 2021 1:05 pm من طرف بن عبد الله» صوفية السحيري بن حتيرة: النص والجسد من منظور تاريخي أنثروبولوجيالخميس يونيو 24, 2021 1:01 pm من طرف بن عبد الله» من السابق لأوانه معرفة ما إذا كانت الروبوتات تطور المهارات الاجتماعية لدى الأطفال المصابين بالتوحدالخميس يونيو 24, 2021 12:50 pm من طرف بن عبد الله» لا تستنع الى الفاشلين القمة في انتظارك انت اقوى مما تظنالأربعاء يونيو 23, 2021 6:27 pm من طرف بن عبد الله |
|
الأحداث 
المنشورات 