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Create your own Custom Search Engine
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Create your own Custom Search Engine

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თქვენი ღონისძიების ჩასატარებლად ეროვნულ სამეცნიერო ბიბლიოთკაში, გთხოვთ, შეავსოთ სააპლიკაციო ფორმა და გადგმოგზავნოთ ელექტრონულ მისამართზე: infopr@sciencelib.ge

მსოფლიო სამეცნიერო სიახლეები

ტერეზა მეის ოპონენტები უნდობლობის გამოცხადებით ემუქრებიან

რადიო თავისუფლება - 2 საათი 51 წთ-ს წინ
„თუ ჩვენ არ ვივლით წინ ამ შეთანხმებისკენ, არავინ იცის, ამას რა შედეგები მოჰყვება. ეს შესაძლოა იყო გზა ღრმა და სერიოზული გაურკვევლობისაკენ, მაშინ როცა ბრიტანელ ხალხს სურს, რომ ჩვენ ბოლო მოვუღოთ ამ გაურკვევლობას“, - განაცხადა ტერეზა მეიმ 15 ნოემბერს პარლამენტში გამართული დებატების შემდეგ.

Rechtschreibrat: Genderstern wird noch nicht empfohlen

SPIEGEL ONLINE - Kultur - 2 საათი 51 წთ-ს წინ
Entscheiden tut offenbar weh: Wieder hat der Rat für deutsche Rechtschreibung seine Empfehlungen für gendergerechtes Schreiben vertagt. Lösungen wie den Genderstern wolle man noch länger beobachten.

Endor (EDR) est introduit en bourse sur CoinAll, le premier centre d'échanges partenaire d'OKEx

Yahoo! Actualités: Les titres Sciences - 2 საათი 55 წთ-ს წინ
BEIJING, 16 novembre 2018 /PRNewswire/ -- CoinAll ( www.coinall.com ), le premier centre d'échanges partenaire d'OKEx, a annoncé l'introduction en bourse d'Endor, un protocole bien connu utilisant la technologie ...

Souriez, Facebook regarde votre famille

Yahoo! Actualités: Les titres Sciences - 2 საათი 56 წთ-ს წინ
Le réseau social veux scanner vos profils pour mieux connaître votre foyer. En mai, Facebook a déposé le brevet (publié seulement récemment) d'une technologie qui lui permettrait d'analyser des photos de famille pour établir le profil complet d'un foyer. Cette intelligence artificielle (IA) aurait aussi pour but, bien sûr, de pouvoir vendre des ...

არასამთავრობოები:ცესკოს გადაწყვეტილება არ ითვალისწინებს საქართველოს მოქალაქეების ინტერესებს

რადიო თავისუფლება - 3 საათი 2 წთ-ს წინ
ცენტრალური საარჩევნო კომისიის გადაწყვეტილება არჩევნების 28 ნოემბერს დანიშვნის შესახებ მიუღებელი და არამიზანშეწონილია-აღნიშნულია არასამთავრობო ორგანიზაციების ერთობლივ განცხადებაში. ”მოცემული გადაწყვეტილებით საარჩევნო ადმინისტრაციამ მხედველობაში არ მიიღო საზღვარგარეთ მყოფი საქართველოს მოქალაქეების ინტერესი და უფლება მონაწილეობა მიიღონ არჩევნებში, შეუქმნა რა მათ ხელოვნური ბარიერი არჩევნების სამუშაო დღეს დანიშვნით. მათ მიერვე შექმნილი პრობლემით გამოწვეული ზიანის შესამცირებლად ცესკომ...

"Lindenstraße"-Erfinder: Geißendörfer kann Absetzung nicht verstehen

SPIEGEL ONLINE - Kultur - 3 საათი 3 წთ-ს წინ
Den Erfinder der "Lindenstraße" hat die Absetzung der Serie ebenso kalt erwischt wie die Fans des Dauerbrenners. Nun hat sich Hans W. Geißendörfer per Twitter zu der Entscheidung geäußert.

Voiture : « Merci à tous ceux qui font autrement »

LeMonde - bio, environ, sciences - 3 საათი 6 წთ-ს წინ
Olivier Razemon, spécialiste de la mobilité quotidienne, rend hommage à ceux qui préfèrent laisser leur voiture au garage.

Danse : la belle austérité d’Anne Teresa De Keersmaeker

lemonde.fr - Culture - 3 საათი 9 წთ-ს წინ
« Mitten wir Im Leben Sind », sur du Bach, est présenté à la Philharmonie de Paris dans le cadre du Festival d’automne.

La SNCF aura des trains à hydrogène début 2022

Yahoo! Actualités: Les titres Sciences - 3 საათი 13 წთ-ს წინ
La SNCF cessera d'utiliser des locomotives diesel d'ici 2030-2035, pour les remplacer notamment par des trains à propulsion hydrogène. "Il faut qu'on arrive à sortir du diesel ferroviaire non pas ...

These U.S.-Russia polar bears are doing just fine

Futurity.org - 3 საათი 17 წთ-ს წინ

Not all polar bears are in the same dire situation as they face retreating sea ice, at least not right now, a new study shows. Those that hang out in the Chukchi Sea off the western coast of Alaska are doing well. But they’ve never been counted. Until now.

The first formal study of this population, which appears in Scientific Reports, suggests it’s been healthy and relatively abundant in recent years, numbering about 3,000 animals.

“This work represents a decade of research that gives us a first estimate of the abundance and status of the Chukchi Sea subpopulation,” says first author Eric Regehr, a researcher with the Polar Science Center at the University of Washington.

Polar bear with a bloody face from feedingA polar bear with a bloody face after feeding on a walrus carcass in 2018 on Wrangel Island. (Credit: Eric Regehr/U. Washington)

“Despite having about one month less time on preferred sea ice habitats to hunt compared with 25 years ago, we found that the Chukchi Sea subpopulation was doing well from 2008 to 2016,” Regehr says.

“Sea-ice loss due to climate change remains the primary threat to the species but, as this study shows, there is variation in when and where the effects of sea-ice loss appear. Some subpopulations are already declining while others are still doing OK.”

Stressed bears

Of the world’s 19 subpopulations of polar bears, the US shares two with neighboring countries. The other US subpopulation—the southern Beaufort Sea polar bears, whose territory overlaps with Canada—is showing signs of stress.

“The southern Beaufort Sea subpopulation is well-studied, and a growing body of evidence suggests it’s doing poorly due to sea-ice loss,” Regehr says.

The US Endangered Species Act in 2008 listed polar bears as threatened due to declining sea ice, which the animals depend on for hunting, breeding, and traveling. But the new study suggests that such effects are not yet visible for bears in the remote waters that separate Alaska from Chukotka, Russia.

“It’s a very rich area. Most of the Chukchi Sea is shallow, with nutrient-rich waters coming up from the Pacific. This translates into high biological productivity and, importantly for the polar bears, a lot of seals,” Regehr says.

Map of the Chukchi Sea The striped area on the left shows the Chukchi Sea polar bear subpopulation’s range. Sea ice reaches south to the dotted line in winter, and retreats to the solid black line in summer. The right shows a closeup of the study area off Alaska’s coast. White circles show where researchers tagged polar bears between 2008 and 2016. (Credit: Regehr et al./Scientific Reports)

Previous studies by the State of Alaska show that ringed and bearded seals have maintained good nutritional condition and reproduction in the Chukchi Sea region, Regehr says.

“Just flying around, it’s night and day in terms of how many seals and other animals you see. The Chukchi Sea is super productive and the Beaufort Sea is less so,” he says.

The area also has an abundance of whale traffic, and when carcasses wash up on shore the polar bears can feed on them in summer, when the sea ice melts and a portion of the Chukchi Sea subpopulation waits on land for the ocean to refreeze.

Recent ecological observations had suggested that Chukchi Sea bears are doing well. A study led by coauthor Karyn Rode, at the US Geological Survey, showed the top predators have similar amounts of body fat as 25 years ago, a good indicator of their overall health.

GPS tracking

The study is the first assessment of the subpopulation size using modern methods. It estimates just under 3,000 animals, with generally good reproductive rates and cub survival.

As a federal wildlife biologist based in Alaska until 2017, Regehr and colleagues gathered the data by tagging roughly 60 polar bears in most years from 2008 to 2016. He flew by helicopter over the area just north of Alaska’s Seward Peninsula, looking for tracks on the sea ice.

The helicopter then would follow tracks in the snow to locate the bear and use a tranquilizer dart to sedate the animal. Over about an hour, researchers would weigh the bear, collect biological samples, apply individual tags and, in some cases, attach a GPS transmitter.

polar bears on whale carcassPolar bears on a whale carcass on Wrangel Island in 2017. When whale carcasses wash ashore they provide an occasional food source for polar bears in summer months. (Credit: Max Stephenson)

All the data were incorporated into a new model designed to estimate population size for large carnivores that are highly mobile and whose territory spans a large region. The authors made the model publicly available in the hope that it will be used on other populations or species.

“Polar bears can travel thousands of miles in a year. But with the GPS tags, we can see when a bear leaves our study area but is still alive, because it’s moving. This information is key because there are bears that we see once and never see again, and to get a good population estimate you need to know if these animals died or just moved to a new area,” Regehr says.

Native hunters

For the first time, the model also considered local and traditional ecological knowledge that the North Slope Borough of Alaska collected from Native hunters and community members who have generations of experience with polar bears.

“It was important to bring our science together with the observations and expertise of people who live in polar bear country year-round and understand the animals in different ways,” Regehr says.

A joint US-Russia commission is responsible for management and conservation of the Chukchi Sea subpopulation. In response to the new assessment, the commission raised the sustainable level of subsistence harvest, which is nutritionally and culturally important to Native people in Alaska and Chukotka.

“These polar bears move back and forth between the US and Russia, so it’s very much a shared resource,” says Regehr.

“These findings are good news for now, but it doesn’t mean that bears in the Chukchi Sea won’t be affected by ice loss eventually,” Regehr says. “Polar bears need ice to hunt seals, and the ice is projected to decline until the underlying problem of climate change is addressed.”

Additional coauthors are from the University of Washington, the US Geological Survey, and the US Fish and Wildlife Service in Alaska.

The US Fish and Wildlife Service, the US Geological Survey, the University of Washington, the US Air Force, the State of Alaska, the Bureau of Ocean and Energy Management, the Bureau of Land Management, and the National Fish and Wildlife Foundation funded the work.

Source: University of Washington

The post These U.S.-Russia polar bears are doing just fine appeared first on Futurity.

EE and Virgin Media fined £13.3m for overcharging customers

BBC Technology - 3 საათი 19 წთ-ს წინ
Digital minister Margot James says phone and broadband firms must "play by the rules".
კატეგორიები: ახალი ტექნოლოგიები

Nvidia: Der nächste Tech-Wert im Crash-Modus

Wissen - FAZ.NET Frankfurter Algemeine - 3 საათი 23 წთ-ს წინ
Anleger fliehen seit Wochen in Scharen aus den amerikanischen Tech-Werten. Nun erwischt es den Chiphersteller Nvidia. Die Enttäuschung ist groß, der Aktienkurs verliert zeitweise über 17 Prozent. Einen Teil der Schuld tragen Kryptoanlagen wie der Bitcoin.

Rachida Brakni : « Je n’ai jamais attendu que le téléphone sonne »

lemonde.fr - Culture - 3 საათი 29 წთ-ს წინ
Comment percer dans le théâtre lorsqu’on n’a aucun réseau ? Il faut savoir se retrousser les manches, rencontrer des gens et se nourrir intellectuellement, raconte Rachida Brakni. L’actrice, qui sera sur scène dans la pièce « J’ai pris mon père sur mes épaules », revient sur son parcours, du Conservatoire à la réalisation d’un film.

Waldbrände in Kalifornien: Die mühsame Suche nach dem ersten Funken

SPIEGEL ONLINE - Wissenschaft - 3 საათი 29 წთ-ს წინ
Bei den Waldbränden in Kalifornien sind mindestens 65 Menschen gestorben. Brandermittler versuchen herauszufinden, wie die Feuer entstanden sind. Wie geht das und wie hoch sind die Erfolgschancen?
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