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

მსოფლიო სამეცნიერო სიახლეები

A car that flies like 007’s autogyro

The Economist : Science and technology - ხუთ, 19/07/2018 - 18:55

OK Blofeld. I’m coming after you

UNUSUAL aircraft are a regular sight at the Farnborough air show, which opened in Britain this week. But the particular unusualness of the Liberty is not so much that it is a flying car, but that flies as an autogyro. Although the Liberty remained firmly on the ground during the show, it is described by its makers, PAL-V, a Dutch firm, as a “production model” that will be used to obtain the necessary approvals for use on the road and in the air, so that deliveries can begin in 2020.

Autogyros have been around since the early days of aviation. Amelia Earhart set an altitude record in one in 1931. Three years later, an autogyro carried a soon-to-be jilted groom to what he thought would be his wedding, in a film called “It Happened One Night”. Another film, “You Only Live Twice”, which was released in 1967, featured an autogyro called Little Nellie, piloted by James Bond.

Like a small plane, an...

Python has brought computer programming to a vast new audience

The Economist : Science and technology - ხუთ, 19/07/2018 - 18:55

IN DECEMBER 1989 Guido van Rossum, a Dutch computer scientist, set himself a Christmas project. Irked by shortcomings in other programming languages, he wanted to build his own. His principles were simple. First, it should be easy to read. Rather than sprawling over line-endings and being broken up by a tangle of curly braces, each chunk would be surrounded with indented white space. Second, it should let users create their own packages of special-purpose coding modules, which could then be made available to others to form the basis of new programs. Third, he wanted a “short, unique and slightly mysterious” name. He therefore called it after Monty Python, a British comedy group. The package repository became known as the Cheese Shop.

Nearly 30 years after his Christmas invention, Mr Van Rossum resembles a technological version of the Monty Python character who accidentally became the Messiah in the film “Life of Brian”. “I certainly didn’t set out to create a language that was intended for mass...

The safety of CRISPR-Cas9 gene editing is being debated

The Economist : Science and technology - ხუთ, 19/07/2018 - 18:55

A GREAT deal rides on the accuracy of the gene-editing tool known as CRISPR-Cas9. Since its discovery in 2012 it has become popular for tinkering with genomes of all kinds, thanks to its ability to make editing cheap and easy. Firms such as CRISPR Therapeutics, Intellia Therapeutics and Editas Medicine have been built on the idea that it could be used to develop treatments for human diseases. Editas, based in Cambridge, Massachusetts, announced this year that it would work on five new human medicines over the next five years. 

In China the technology is already in clinical use. In Hangzhou Cancer Hospital, for example, CRISPR-Cas9 is being employed to engineer immune-system cells removed from patients with cancer of the oesophagus. The hope is that when the engineered cells are returned to a patient’s body, the editing will have improved their ability to attack tumours. More studies involving human beings are expected in other countries for the treatment of beta-thalassaemia, a...

Viruses that attack bacteria have evolved to collaborate

The Economist : Science and technology - ხუთ, 19/07/2018 - 18:55

Leader of the pack

THAT predators often hunt in packs is a commonplace. Wolves do it. Killer whales do it. Even Velociraptor, a species of dinosaur made famous by “Jurassic Park”, is believed to have done it. These are, or were, all intelligent species, capable of exchanging and interpreting information. But the logic of pack hunting, that many may achieve what one alone cannot, and that individual pack members may perform different roles, does not depend on intelligence. Indeed, evidence has now emerged that this logic applies to viruses, the simplest biological entities of all. It was published this week in Cell, by Edze Westra and Stineke van Houte at the University of Exeter, in England.

The viruses in question are bacteriophages, which “hunt” bacteria. They do not eat their prey. Rather, they take over its genetic apparatus to create replicas of themselves, killing the host as a consequence. To do so they have to...

An excavation in the Middle East shows that baking predates farming

The Economist : Science and technology - ხუთ, 19/07/2018 - 18:55

Crumbs!

ABSENCE of evidence is not evidence of absence. The value of that aphorism has just been shown by a discovery made at Qa’ Shubayqa, in north-eastern Jordan. Amaia Arranz-Otaegui of the University of Copenhagen and her colleagues found breadcrumbs in two ancient fireplaces there. Not that unusual as archaeological discoveries go, except that these fireplaces were between 14,200 and 14,400 years old. The loaves the crumbs came from were thus baked more than 4,000 years before the beginning of agriculture.

That bread was coeval with cereal farming was an easy idea to accept in the absence of contrary evidence—as was the case until the publication of Dr Arranz-Otaegui’s discovery in the Proceedings of the National Academy of Sciences. Before it, the oldest evidence of breadmaking was from 9,100 years ago, in Anatolia.

Altogether, Dr Arranz-Otaegui and her colleagues found 24 charred breadcrumbs (one of which is pictured)...

Concern about “sexualised” children often misses the point

The Economist: International - ხუთ, 19/07/2018 - 18:55

IN JAPAN it is hard to avoid the disturbing spectacle of young girls being treated as sex objects. Rorikon, an abbreviation of “Lolita complex”, is ubiquitous. In M’s Pop Life, a sex shop in Tokyo’s Akihabara district, known for its pop subculture, life-size models of girls, their breasts at various stages of puberty, are openly on sale. Elsewhere big-bosomed cartoon girls are splashed across posters; children (or grown-ups made to look like children) pose in magazines in bikinis.

Rorikon is a peculiarly Japanese phenomenon. But across the world there are growing concerns about children being portrayed sexually, and the effects on the children themselves. This comes in two forms. The first, “direct” sexualisation, includes advertising, television programmes and magazine content that portray children, especially girls, as sexually aware or active. It also includes goods aimed at children who are seen as trying to make...

ტრამპი: მოუთმენლად მოველი პუტინთან „მეორე შეხვედრას“

აშშ-ის პრეზიდენტმა, დონალდ ტრამპმა შეაქო რუსეთის პრეზიდენტთან, დონალდ ტრამპთან თავისი ამასწინანდელი შეხვედრა, როგორც „დიდი წარმატება“ და განაცხადა, რომ მოუთმენლად მოელის პუტინთან „მეორე შეხვედრას“, რათა განახორციელონ ჰელსინკიში განხილული თემები. ტრამპმა 19 ივლისს ტვიტერით გავრცელებულ განცხადებაში გააკრიტიკა პრესა, მისი აზრით, რუსეთის ლიდერთან შეხვედრის უარყოფითი გაშუქებისთვის. „რუსეთთან სამიტი დიდი წარმატება იყო“, წერდა ტრამპი, „ხალხის ნამდვილი მტრის, „ყალბი ამბების მედიის“ გამოკლებით....

Moving closer to completely optical artificial neural network

ScienceDaily Energy Techn. Matter - ხუთ, 19/07/2018 - 18:48
Researchers have shown that it is possible to train artificial neural networks directly on an optical chip.
კატეგორიები: ახალი ტექნოლოგიები

Methods to quantify the yips and golfer's cramp

ScienceDaily Energy Techn. Matter - ხუთ, 19/07/2018 - 18:48
Almost every golfer knows the feeling. Minutes after a picture-perfect drive down the fairway, a cascade of inexplicable missed putts leads to a disappointing triple bogey.
კატეგორიები: ახალი ტექნოლოგიები

Future electronic components to be printed like newspapers

ScienceDaily Comp&Math - ხუთ, 19/07/2018 - 18:48
A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.
კატეგორიები: მათემატიკა

Future electronic components to be printed like newspapers

ScienceDaily Energy Techn. Matter - ხუთ, 19/07/2018 - 18:48
A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.
კატეგორიები: ახალი ტექნოლოგიები

Computer model predicts how fracturing metallic glass releases energy at the atomic level

ScienceDaily Energy Techn. Matter - ხუთ, 19/07/2018 - 18:48
Metallic glasses are an exciting research target, but the difficulties associated with predicting how much energy these materials release when they fracture is slowing down development of metallic glass-based products. Recently, researchers developed a way of simulating to the atomic level how metallic glasses behave as they fracture. This modeling technique could improve computer-aided materials design and help researchers determine the properties of metallic glasses.
კატეგორიები: ახალი ტექნოლოგიები

ADHD drugs do not improve cognition in healthy college students

ScienceDaily Med - ხუთ, 19/07/2018 - 18:48
Contrary to popular belief across college campuses, attention deficit hyperactivity disorder (ADHD) medications may fail to improve cognition in healthy students and actually can impair functioning.
კატეგორიები: მედიცინა

გიორგი კეკელიძის ლექცია და ქართული ბიბლიოთეკის გახსნა ოდესაში

გიორგი კეკელიძის ლექცია და ქართული ბიბლიოთეკის გახსნა ოდესაში

18 ივლისს ოდესის ნაციონალურ ბიბლიოთეკაში გიორგი კეკელიძის საჯარო ლექცია–სემინარი გაიმართა, რომელსაც ოდესის ოლქის ბიბლიოთეკარები დაესწრნენ.

სრული ტექსტი

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Anglerfish and their headlamp bacteria have a crazy relationship

Futurity.org - ხუთ, 19/07/2018 - 18:33

Researchers have sequenced and analyzed the genomes of the glowing bacteria living in the bulbs that hang off the heads of anglerfish.

The anglerfish lives most of its life in total darkness more than 1,000 meters below the ocean surface. Female anglerfish sport a glowing lure on top of their foreheads, basically a pole with a light bulb on the end, where bioluminescent bacteria live. The light-emitting lure attracts both prey and potential mates to the fish.

Little is known about anglerfish and their symbiotic relationship with these brilliant bacteria, because the fish are difficult to acquire and study. The bacteria researchers studied in the new research came from fish specimens collected in the Gulf of Mexico.

via GIPHY

The researchers report their findings in the journal mBio. The analysis reveals that the bacteria have lost some of the genes that are needed to live freely in the water. That’s because the fish and bacteria developed a tight, mutually beneficial relationship, where the bacteria generate light while the fish supplies nutrients to the microbe.

“What’s particularly interesting about this specific example is that we see evidence that this evolution is still underway, even though the fish themselves evolved about 100 million years ago,” says lead author Tory Hendry, assistant professor of microbiology at Cornell University. “The bacteria are still losing genes, and it’s unclear why.”

“…this is a third type of situation where the bacteria are not actually stuck with their host but they are undergoing evolution.”

Most of the known symbiotic relationships between organisms and bacteria are between either a host and free-living bacteria that don’t evolve to maintain a symbiosis, or a host and intracellular bacteria that live inside the host’s cells and undergo huge reductions in their genomes through evolution.

The bacteria inside the bulb in anglerfish represents a third type of symbiosis, where preliminary data suggest these bacteria may move from the anglerfish bulb to the water. “It’s a new paradigm in our understanding of symbiosis in general; this is a third type of situation where the bacteria are not actually stuck with their host but they are undergoing evolution,” Hendry says.

Genetic sequencing showed that the genomes of these anglerfish bioluminescent bacteria are 50 percent reduced compared with their free-swimming relatives. The bacteria have lost most of the genes associated with making amino acids and breaking down nutrients other than glucose, suggesting the fish may be supplying the bacteria with nutrients and amino acids.

Is symbiosis just a sneaky way to take, take, take?

At the same time, the bacteria have retained some genes that are useful in water outside the host. They have full pathways to make a flagellum, a corkscrew tail for moving in water. The bacteria had lost most of the genes involved in sensing chemical cues in the environment that may lead to food or other useful compounds, though a few remained, leaving a subset of chemicals they still respond to.

“They were pared down to something they cared about,” Hendry says.

The Gulf of Mexico Research Initiative funded the study.

Source: Cornell University

The post Anglerfish and their headlamp bacteria have a crazy relationship appeared first on Futurity.

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