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ძიება ქართულ ლექსიკონებში და ენციკლოპედიებში
Create your own Custom Search Engine
ძიება მსოფლიოს უნივერსიტეტების ღია სამეცნიერო არქივებში

Create your own Custom Search Engine

ღონისძიების ჩატარება ეროვნულ სამეცნიერო ბიბლიოთკაში

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

მსოფლიო სამეცნიერო სიახლეები

How the Earth stops high-energy neutrinos in their tracks

ScienceDaily Energy Techn. Matter - ოთხ, 22/11/2017 - 22:13
For the first time, a science experiment has measured Earth's ability to absorb neutrinos -- the smaller-than-an-atom particles that zoom throughout space and through us by the trillions every second at nearly the speed of light. The experiment was achieved with the IceCube detector, an array of 5,160 basketball-sized sensors frozen deep within a cubic kilometer of very clear ice near the South Pole.
კატეგორიები: ახალი ტექნოლოგიები

Surprising roles for muscle in tissue regeneration, study finds

ScienceDaily Med - ოთხ, 22/11/2017 - 22:13
Researchers have illuminated an important role for different subtypes of muscle cells in orchestrating the process of tissue regeneration. Notably, in the absence of these muscles, regeneration fails to proceed.
კატეგორიები: მედიცინა

Surprising roles for muscle in tissue regeneration, study finds

ScienceDaily Plants&Animals - ოთხ, 22/11/2017 - 22:13
Researchers have illuminated an important role for different subtypes of muscle cells in orchestrating the process of tissue regeneration. Notably, in the absence of these muscles, regeneration fails to proceed.
კატეგორიები: ბიოლოგია

Lightning, with a chance of antimatter

ScienceDaily Chemistry - ოთხ, 22/11/2017 - 22:13
Researchers find that lightning strikes causes photonuclear reactions in the atmosphere, creating antimatter.
კატეგორიები: ქიმია

Lightning, with a chance of antimatter

ScienceDaily Energy Techn. Matter - ოთხ, 22/11/2017 - 22:13
Researchers find that lightning strikes causes photonuclear reactions in the atmosphere, creating antimatter.
კატეგორიები: ახალი ტექნოლოგიები

"184 ქვეყნის 15 ათასზე მეტი მეცნიერი კაცობრიობას მეორედ აფრთხილებს"

geonews.ge - ოთხ, 22/11/2017 - 22:08
"184 ქვეყნის 15 ათასზე მეტმა მეცნიერმა უკვე  მეორედ მოაწერა ხელი "გაფრთხილებას კაცობრიობისთვის", სადაც აღწერილია  ძირითადი საფრთხეები, რომელიც ადამიანებს ემუქრება. მეცნიერთა პირველი დოკუმენტი 1992 წელს  გამოქვეყნდა და მას მსოფლიოს მასშტაბით,  დაახლოებით 1700 მეცნიერი აწერდა ხელს. ისინი დედამიწაზე სიცოცხლის განადგურებას წინასწარმეტყველებდნენ. ამის მიზეზად კი ოზონის ხვრელის გაზრდას, ჰაერისა და წყლის დაბინძურებას, ტყეების გაჩეხვას, ნიადაგის გამოფიტვას და ადამიანის ჩარევის შედეგად სხვა შედეგებს ასახელებდნენ. ახალ დოკუმენტში, რომელშიც პირველი გაფრთხილების გამოქვეყნების შემდეგ  25 წლიანი პერიოდია შეჯამებული,  ნათქვამია, რომ კაცობრიობამ ვერ მიაღწია საკმარის პროგრესს გარემოს პრობლემების მოგვარების საკითხებში და  ბევრი მათგანი  უფრო სერიოზული გახდა. მთავარ პრობლემად ექსპერტები კლიმატის ცვლილებას მიიჩნევენ. 1992 წლიდან საშუალო ტემპერატურის ზრდა 0.5  გრადუსზე მეტს შეადგენს, ნახშირორჟანგის გამოყოფა  62 პროცენტით გაიზარდა,  შემცირდა  ტყეების რაოდენობა,  ოკეანეებში იზრდება მკვდარი ზონები, იკლებს   ჟანგბადის შემცველობა, რაც თევზის რაოდენობის შემცირებას იწვევს. ასევე, ძუძუმწოვართა მრავალი სახეობა 30 პროცენტით შემცირდა. ამ დროს კი ადამიანთა რიცხვი ორი მილიარდით გაიზარდა. მეცნიერები ამბობენ, რომ თუ გადამწყვეტ ღონისძიებებს არ მიმართავენ, მალე ძალიან გვიან იქნება და კაცობრიობის გადარჩენა შეუძლებელი გახდება,  დოკუმენტის ავტორები პრობლემის გადაწყვეტას ნაკრძალების შექმნაში, საკვების ნარჩენების რაოდენობის შემცირებაში და ეკოლოგიურად უფრო სუფთა ტექნოლოგიების დანერგვაში ხედავენ. "

საქართველოს მოქალაქეების უკრაინიდან დეპორტაციას რადას უფლებამდამცველი ეხმაურება

Ambebi.Ge - ოთხ, 22/11/2017 - 22:07
უკრაინის რადას უფლებამდამცველი საქართველოს მოქალაქეებთან მიმართებაში დარღვეული კანონმდებლობის შესახებ საუბრობს

Putin, Erdogan und Rohani schmieden eine Syrien-Allianz

Wissen - FAZ.NET Frankfurter Algemeine - ოთხ, 22/11/2017 - 22:06
Eigentlich haben Russland, Iran und die Türkei im Syrien-Konflikt verschiedenste Interessen. Bei einem Treffen zeigten sich die Staatschefs der drei Länder nun aber überraschend einig – und stellen einen Plan auf. Doch einige Streitpunkte bleiben.

Timelapse reveals eight-year construction of Louvre Abu Dubai in just three minutes

dezeen - ოთხ, 22/11/2017 - 22:00

EarthCam Louvre Abu Dhabi Timelapse

A timelapse video from the webcam provider EarthCam reveals the intricate process of constructing the geometric dome of the new Jean Nouvel-designed Louvre Abu Dhabi. Read more

Muscle plays surprising role in tissue regeneration

MIT Top News - ოთხ, 22/11/2017 - 22:00
Researchers at the Whitehead Institute have illuminated an important role for different subtypes of muscle cells in orchestrating the process of tissue regeneration. In a paper appearing online today in Nature , they reveal that a subtype of muscle fibers in flatworms is required for triggering the activity of genes that initiate the regeneration program. Notably, in the absence of these muscles, regeneration fails to proceed. Another type of muscle, they report, is required for giving regenerated tissue the proper pattern — for example, forming one head instead of two. “One of the central mysteries in organ and tissue regeneration is: How do animals initiate all of the cellular and molecular steps that lead to regeneration?” says senior author Peter Reddien, a member of Whitehead Institute, professor of biology at MIT, and investigator with the Howard Hughes Medical Institute. “We’ve helped answer this question by revealing a surprising molecular program that operates within a subgroup of muscle cells that helps establish the molecular information required for proper tissue regeneration after injury.” For more than a decade, Reddien and the researchers in his laboratory have studied the biological mechanisms that underlie regeneration in a tiny flatworm called planarians. These worms possess some impressive regenerative capabilities: When sliced in two, each piece of the worm can regrow the body parts needed to form two complete organisms. In previous studies, Reddien’s team identified a set of always-on genes, known as position control genes (PCGs), that provide cells with region-specific instructions, like a set of GPS coordinates, that tell cells where they are in the body, and thus what body part to regenerate. Interestingly, PGCs are active in planarian muscle cells, suggesting muscle may play a major role in the regeneration process. “This discovery raised a lot of questions about how muscle participates in this process,” Reddien says. In planarians, there are a handful of muscle cell types. For example, if you imagine the worms as simple cylindrical tubes, there are longitudinal muscle fibers, which run head-to-tail along the tubes’ long axis. There are also circular fibers, which are perpendicular to the longitudinal fibers and hug the tubes’ outer circumference. To assess the roles of these different muscle cell types in regeneration, first author Lucila Scimone and her colleagues needed a method to selectively remove them. When myoD, a gene found specifically in the longitudinal fibers, is inhibited, those fibers fail to form. Similarly, the nkx1-1 gene marks the circular fibers, and when its function is reduced, they do not develop. Using these genes as molecular scalpels, Scimone and her co-authors could test the effects of ablating these distinct muscle groups on regeneration. Surprisingly, when the longitudinal fibers were removed, the results were dramatic. The worms live quite normally, but when they are injured (the head removed, for example) they cannot regenerate the missing parts. “This is an amazing result; it tells us that these longitudinal fibers are essential for orchestrating the regeneration program from the very beginning,” says Scimone, a scientist in Reddien’s lab. As the researchers dug deeper into the finding, they learned that the functions of two critical genes are disrupted when longitudinal fibers are missing. These genes, called notum and follistatin, are known for their fundamental roles in regeneration, controlling head-versus-tail decisions and sustained cell proliferation, respectively, following tissue injury. In addition to this essential role for longitudinal fibers, the research team also uncovered a key role for circular fibers. When these muscles are missing, planarians are able to regenerate missing body parts, but what regrows is abnormally patterned. For example, two heads may be regenerated within a single outgrowth, instead of one. These results underscore an important and previously unappreciated role for muscle, widely known for its contractile properties, in instructing the tissue regeneration program. The Whitehead researchers will continue to probe the role of different muscle cell types in planarian regeneration and also explore whether other animals with regenerative capabilities possess a similar muscle-localized program for conferring positional information. “It’s hard to understand what limits humans’ abilities to regenerate and repair wounds without first knowing what mechanisms are enabling some animals, like planarians, to do it so amazingly well,” Reddien says. This work was supported by the National Institutes of Health, Howard Hughes Medical Institute, and the Eleanor Schwartz Charitable Foundation.

Should the Social Cost of Carbon Be Higher​?

Scientific American - ოთხ, 22/11/2017 - 22:00
Scientists say that even under the Obama administration, the number may have been set too low -- Read more on ScientificAmerican.com

Gearing up for the internet of things

MIT Top News - ოთხ, 22/11/2017 - 21:55
Telecommunications is gearing up for explosive growth of the internet of things (IoT), the massive collection of devices — smart watches, smart thermostats, traffic and energy monitors, etc. — that will be given network connectivity so that they can communicate and exchange data. The big question raised by the IoT is capacity: How can a telecommunications network with limited spectrum serve thousands or millions of devices at once? Existing networks cannot support the addition of exponentially more devices, nor the near-instantaneous connection speed necessary for machine-to-machine communication. The next-generation network, 5G, must be designed to meet these requirements. How to prepare global wireless networks for the IoT was the topic of discussion at the National Science Foundation Workshop on Low-Latency Wireless Random-Access , hosted by MIT’s Laboratory for Information and Decision Systems (LIDS) and sponsored by the National Science Foundation (NSF) and the Center for the Science of Information (CSoI). The two-day event took place on the MIT campus in early November, and more than 20 speakers from MIT, other universities, and companies including Qualcomm, SigFox, and Huawei presented their work on how to solve the network challenges created by the IoT. “Developing solutions for massive multi-access wireless communications is a fascinating, domain-spanning challenge for researchers with considerable practical applications,” said MIT associate professor and LIDS faculty member Yury Polyanskiy, who organized the workshop. The IoT will transform industries such as agriculture, transportation, utilities, athletics, and more by introducing smart devices and many networked monitors. The monitors will provide live environmental feedback, which the devices can use to optimize their functions. Determining 5G standards and protocols that will allow these transformative technological developments is a complex undertaking. There are numerous hurdles to redesigning wireless infrastructure for the IoT. First, current networks are optimized for a relatively small set of users, mostly human, sending large amounts of data — a phone call, a video — in a continuous stream, with different connections centrally organized. To accommodate the IoT, networks will have to manage decentralized, intermittent transmission of many small data packets from many, many more users, mostly machines. This vast increase in machines on the network will lead to more interference, which causes latency or loss of connectivity. Just like people have trouble getting a call through at a large event where there are too many other people on their phones, machines will have trouble sending their data if the network gets overloaded with devices needing connectivity. Devices that spend too much time searching for a working connection will also wear out their batteries, an issue for IoT monitors that are meant to be very low energy and low cost. Another big challenge for the IoT is that it requires extremely low latency, or lag. As anyone who has used the internet knows, data don't always transmit at the speed you want them to. And although a half-loaded video or delayed text may be a pain for humans, for machines even a few milliseconds of lag can have serious consequences. A smart car interpreting traffic data, for instance, cannot afford any lag. This is why the goal for 5G is an ambitious one millisecond latency between devices. These issues were discussed at length during the workshop. Two sessions were dedicated to information theory, with academic speakers sharing their models for better massive machine-type communications. Sessions also covered topics including reliability and security. “We don’t have one thing to solve, we have many things to solve,” said the first speaker of the event, Christophe Fourtet, co-founder and chief science officer of telecommunications company SigFox. The workshop provided a somewhat rare opportunity for academia and industry to exchange ideas, as these communities are often siloed from each other. “Academics played a major role in establishing early telecommunication standards, but this has become more rare recently. With 5G calling for radically new simple network-access methods, though, it’s a great opportunity for academics to play a big role again,” said Polyanskiy. Presenter Swarun Kumar, assistant professor at Carnegie Mellon University and an MIT alumnus, echoed Polyanskiy’s sentiments. “The time from academic research to industry in this field is too slow,” Kumar said. He made an appeal to the members of industry present at the workshop to reach out to him and other academics, noting that they could solve problems more efficiently together. Kumar presented a local network that he and colleagues at Carnegie Mellon had implemented around the campus as a proof-of-concept for their innovations to network infrastructure. After each set of presentations, speakers returned to the front of the room for a panel Q&A, and in between sessions, speakers and attendees had a chance to mingle and talk over refreshments. The event organizers affirmed that these moments were some of the most valuable of the workshop: a chance for everyone present to open up dialogue and, perhaps, plant the seeds of collaborations that will build a better network.

სიგნალები კოსმოსიდან, მისტიფიკაცია თუ სენსაცია?

astronet.ge - ოთხ, 22/11/2017 - 21:49
 ასტრონომთა ჯგუფმა აღმოაჩინა, რომ ზოგიერთი ვარსკვლავიდან უჩვეულო სიგნალები მოდის, რომლებიც კავშირგაბმულობის სისტემების მუშაობას ჰგავს. მეცნიერები ნაადრევი ხმაურის ატეხას არ აპირებენ, თუმცა, ათასწლეულის ყველაზე უფრო მნიშვნელოვანი აღმოჩენის ზღვართან შეიძლება ვიდგეთ.  უცხოპლანეტელ მოაზროვნე არსებებთან რაიმე ტიპის კონტაქტზე ყველა ოცნებობს, თუნდაც ისინი უზარმაზარი ხოჭოები ან ენერგოფორმები იყონ. ამიტომაც არის, რომ  ყოველი უცნაური სიგნალისა თუ ენერგეტიკული ფლუქტუაციბის აღმოჩენისას, მასმედიაში [...]

ვახტანგ გომელაური - ზარები ხორციელდება ამა თუ იმ მუქარით... ყველაფერს სერიოზულად მივუდგებით

Ambebi.Ge - ოთხ, 22/11/2017 - 21:46
სოციალურ ქსელში მომხმარებელი წერდა, რომ "მომხდარის გამო მოკლული ძმებისთვის საქართველო ათასი თავით გადაიხდის"

Doku "Die rechte Wende": Die Bilder sprechen für sich

SPIEGEL ONLINE - Kultur - ოთხ, 22/11/2017 - 21:44
Einige Menschen entlarven sich selbst, lässt man sie nur lange genug reden. Der Dokumentarfilm "Die rechte Wende" schafft es, das intellektuelle Niveau der rechten Szene zu enthüllen, ohne kommentierend einzugreifen.

New mechanisms found of cell death in neurodegenerative disorders

ScienceDaily Med - ოთხ, 22/11/2017 - 21:40
New mechanisms of cell death have now been discovered, which may be involved in debilitating neurodegenerative disorders, such as Alzheimer's disease and Parkinson's disease, report scientists.
კატეგორიები: მედიცინა
ინფოარხების ცნობების შეკრება