News Of Science

NASA’s newest Mars rover

2020-04-06T09:28:00.000-01:00

The next NASA Mars rover now has a name, Perseverance. It took its first drive in a clean room at NASA’s Jet Propulsion Laboratory in Pasadena, Calif.
see link:
https://www.sciencenewsforstudents.org/article/nasa-newest-mars-rover-named-perseverance?utm_source=&utm_medium=&utm_campaign=
and see also:
https://mars.nasa.gov/mars2020/participate/name-the-rover/

A new form of DNA in our cells

2018-04-25T15:57:00.000-01:00

المواقع العلمية الموثقة Trusted scientific sites

2018-04-10T12:46:00.000-01:00

Samsung Galaxy S9 review

2018-03-22T07:35:00.000-01:00

Samsung Galaxy S9 review

Galaxy S8 | S8+

2017-05-18T11:28:00.002-01:00

The Infinity Display has an incredible end-to-end screen that spills over the phone’s sides, forming a completely smooth, continuous surface with no bumps or angles. It’s pure, pristine, uninterrupted glass. And it takes up the entire front of the phone, flowing seamlessly into the aluminum shell. The result is a beautifully curved, perfectly symmetrical, singular object.

read more on :
http://www.samsung.com/global/galaxy/galaxy-s8/

10 science stories of 2016

2016-12-28T10:39:00.000-01:00

10 science stories of 2016

At first glance, the stories taking the top two spots in Science News’ review of 2016 have little in common. Scientists began searching decades ago for gravitational waves. Discussions of these subtle signals from dramatic and distant phenomena appear dozens of times in the SN archive starting as early as the 1950s. Their long-awaited discovery, our No. 1 story of the year, touched off celebration of a new era in astronomy. ....

مال فائض، كيف تحافظ عليه؟

2016-11-11T17:37:00.000-01:00

مال فائض، كيف تحافظ عليه؟

أعتقد من الأخطاء الفادحة في نظم التعليم العربية أنها لا تحوي أية مادة خاصة بتعليم مبادئ الاستثمار والتخطيط المالي، نحن نتعلم هذا الأمر بالطريقة الصعبة، أي بالتجربة والخطأ والخسارة، أو ننتظر حتى نصل للجامعة لندرس ونختص ونتعلم أكاديميات غير واقعية.

في ظل المشاكل التي تعصف بعدة دول عربية مثل مصر وبعض دول الخليج سواء لأسباب أمنية أو اقتصادية، يطرح دائماً سؤال من العامة، كيف أحافظ على أموالي؟

المصدر :

http://www.mhabash.com/2016/10/31/%D9%84%D8%AF%D9%8A-%D9%85%D8%A7%D9%84-%D9%81%D8%A7%D8%A6%D8%B6%D8%8C-%D9%83%D9%8A%D9%81-%D8%A3%D8%AD%D8%A7%D9%81%D8%B8-%D8%B9%D9%84%D9%8A%D9%87%D8%9F/

most-influential-gadgets

2016-05-04T11:43:00.000-01:00

Google Glass, which cost $1,500 for those invited to a sort of public beta test, never took off. The relatively powerful head-mounted computer provided important signals for the future of wearable technology. Glass showed that designers working on computing devices that are worn face a different set of assumptions and challenges. Glass, for example, made it easy for users to surreptitiously record video, ....

Brain shapes come from mom and dad ..

2015-12-11T15:22:00.000-01:00

Brain shapes come from mom and dad

You can thank your parents for your funny-looking hippocampus. Genes influence the three-dimensional shape of certain brain structures, scientists report in a paper posted online December 1 at bioRxiv.org. Showing a new way that genes help sculpt the brain opens up more ways to explore how the brain develops and operates.

Earlier work linked genes to simple measurements of brain structures, such as overall volume or length. The new work goes beyond that by mathematically analyzing complex 3-D shapes and tying those shapes to a particular genetic makeup.

A team led by researchers at Massachusetts General Hospital and Harvard Medical School analyzed MRI brain scans and genome data from 1,317 healthy young adults. Particular genetic profiles influenced the 3-D shape of structures including the hippocampus, caudate and cerebellum, the scientists found. In some brains, for instance, genes played a role in making the seahorse-shaped right hippocampus skinnier on the top and wider on the bottom. Genes also influenced whether the tail of the caudate was short or long.

Read more From;

https://www.sciencenews.org/article/brain-shapes-come-mom-and-dad?tgt=nr

Nanowires give 'solar fuel cell' efficiency a tenfold boost

2015-07-20T08:33:00.000-01:00

image from :

http://www.redarc.com.au/images/uploads/content/solar_cell.png

Researchers have developed a very promising prototype of a new solar celll. The material gallium phosphide enables their solar cell to produce the clean fuel hydrogen gas from liquid water. Processing the gallium phosphide in the form of very small nanowires is novel and helps to boost the yield by a factor of ten. And does so using ten thousand times less precious material. ..

MIT Physicists Create Ultracold Molecules of 23Na40K

2015-06-14T11:25:00.000-01:00

A team of physicists from MIT has successfully cooled molecules in a gas of sodium potassium (NaK) to a temperature of 500 nanokelvins, creating ultracold molecules.

The air around us is a chaotic superhighway of molecules whizzing through space and constantly colliding with each other at speeds of hundreds of miles per hour. Such erratic molecular behavior is normal at ambient temperatures.

But scientists have long suspected that if temperatures were to plunge to near absolute zero, molecules would come to a screeching halt, ceasing their individual chaotic motion and behaving as one collective body. This more orderly molecular behavior would begin to form very strange, exotic states of matter — states that have never been observed in the physical world.

Now experimental physicists at MIT have successfully cooled molecules in a gas of sodium potassium (NaK) to a temperature of 500 nanokelvins — just a hair above absolute zero, and over a million times colder than interstellar space. The researchers found that the ultracold molecules were relatively long-lived and stable, resisting reactive collisions with other molecules. The molecules also exhibited very strong dipole moments — strong imbalances in electric charge within molecules that mediate magnet-like forces between molecules over large distances. ..

Read more from :

http://scitechdaily.com/mit-physicists-create-ultracold-molecules-of-23na40k/

Computing at the speed of light !

2015-05-23T11:22:00.001-01:00

University of Utah engineers have taken a step forward in creating the next generation of computers and mobile devices capable of speeds millions of times faster than current machines.

The Utah engineers have developed an ultracompact beamsplitter -- the smallest on record -- for dividing light waves into two separate channels of information. The device brings researchers closer to producing silicon photonic chips that compute and shuttle data with light instead of electrons. Electrical and computer engineering associate professor Rajesh Menon and colleagues describe their invention today in the journal Nature Photonics.

Silicon photonics could significantly increase the power and speed of machines such as supercomputers, data center servers and the specialized computers that direct autonomous cars and drones with collision detection. Eventually, the technology could reach home computers and mobile devices and improve applications from gaming to video streaming.

"Light is the fastest thing you can use to transmit information," says Menon. "But that information has to be converted to electrons when it comes into your laptop. In that conversion, you're slowing things down. The vision is to do everything in light." Photons of light carry information over the Internet through fiber-optic networks. But once a data stream reaches a home or office destination, the photons of light must be converted to electrons before a router or computer can handle the information. That bottleneck could be eliminated if the data stream remained as light within computer processors.

"With all light, computing can eventually be millions of times faster," says Menon.

read more from :

http://www.sciencedaily.com/releases/2015/05/150518121153.htm

Spiders spin stronger threads with nanotubes

2015-05-21T10:47:00.000-01:00

Sorry, Kevlar. Spider silk loaded with carbon nanotubes may be the burliest fiber around.

When spritzed with the tiny tubes, spiders spin superstrong, supertough strands of silk. These hardy threads are the toughest fibers ever created, researchers report online April 25 at arXiv.org.

Such fibers could one day replace the heavy steel cables that haul elevator cars up skyscrapers, says materials scientist Mato Knez of CIC nanoGUNE, a research center in San Sebastian, Spain. But that day is still a long way off, says Knez, who wasn’t involved in the work.

“It will probably take another 20 years or more before people can produce a real product out of it,” he says. ...

Read more from :

https://www.sciencenews.org/article/spiders-spin-stronger-threads-nanotubes

Do mosquitoes love you? Blame your parents !

2015-05-16T11:50:00.000-01:00

Mosquitoes are picky eaters. The biting insects go after some of us more than others. Why? Clues lurk within our DNA, a new study finds.

Some people claim they can ward off mosquitoes by drinking beer or eating smelly foods such as garlic. When scientists have tested such claims, they found them false — or at best, unconvincing.

But each of us produces our own natural odors. It is known that mosquitoes find some of these scents especially inviting. And certain lucky people give off scents that keep biting insects away. Soap and perfumes certainly affect how we smell. But science also has shown that our skin odors are rooted at least partly in our genes.

Mandela Fernández-Grandon studies how odors affect animal behavior. While he was working at the London School of Hygiene and Tropical Medicine in England, he was part of an international team. That group of scientists tested whether genes might explain why those blood-sucking insects don’t find us all equally yummy.

The researchers recruited 37 pairs of twins to take part in tests.

Researchers often study twins to tease out genetic effects. Identical twins have the same genes. But as adults, they may differ quite a bit. They may work different jobs, live in very different regions, hang out in very different social groups. Such lifestyle factors may matter more than genes, depending on what a study is measuring. For instance, a recent twins study determined that the strength of our body’s defense system depends less on genes and more on environmental influences.

Read more from :

https://student.societyforscience.org/article/do-mosquitoes-love-you-blame-your-parents

Could we colonise the stars?

2015-05-08T21:37:00.000-01:00

It's fun to speculate about aliens (see "The human universe: If aliens exist, do they know we're here?"). But what if there are no aliens? It's been 65 years since Enrico Fermi first pointed out our solitude. Fermi estimated that it would take an advanced technological civilisation 10 million years or so to fill the galaxy with its spawn. Our galaxy is 10,000 times older than that. Where is everybody?

It's not as though we haven't been looking. Not for long, perhaps, and not very hard, but even a crude estimate suggests there should be other advanced civilisations capable of signalling over interstellar distances. And yet – nothing.

So what if we really are alone, or so isolated as to amount to the same thing? "If we think we are the only life in the universe, we have a huge responsibility to spread life to the stars," says Anders ...

Read more from:

http://www.newscientist.com/article/mg22630190.900-could-we-colonise-the-stars.html?cmpid=EMP|NSNS|2015-0507-GLOBAL-humanuniverse&utm_medium=EMP&utm_source=NSNS&utm_campaign=concept&utm=humanuniverse&cmpid=EMP|NSNS|NSSUB-2015-0507

Application mobile qui détecte l'apnée du sommeil

2015-05-04T14:08:00.003-01:00

Détecter l’apnée du sommeil nécessite actuellement de passer un examen à l'hôpital, ce qui s'avère parfois contraignant et onéreux. Une équipe de chercheurs de l’université de Washington vient de développer une application mobile appelée ApneaApp capable de surveiller la respiration du dormeur sans recourir à d’autres équipements externes. Celle-ci émet des ondes ultrasonores depuis le haut-parleur du smartphone. Ses résultats seraient aussi probants que la polygraphie du sommeil.

Les personnes atteintes d’apnée du sommeil ne s’en rendent pas toujours compte. Or, ce phénomène est plus répandu qu’il n’y paraît. Selon certaines études, elle toucherait entre 4 et 10 % de la population. En France, 1,5 million de personnes souffriraient de ce syndrome silencieux (selon le réseau social Carenity). Celui-ci se manifeste en cours de nuit par une interruption momentanée de la respiration. Les personnes souffrant d’apnée du sommeil présentent en général divers symptômes, notamment une fatigue excessive, une irritabilité, un sommeil fractionné, des troubles de la concentration, des maux de tête ou encore des palpitations.

Selon la Fédération française de cardiologie, l’apnée du sommeil peut même favoriser lesmaladies cardiovasculaires. Le diagnostic de ce syndrome passe par une polygraphie du sommeil qui se pratique à l’hôpital. Un examen qui nécessite la pose d’un ensemble de capteurs pour suivre les mouvements respiratoires, le flux aérien, l’activité cérébrale (électroencéphalogramme), celle des muscles (électromyogramme), le rythme cardiaque, la saturation sanguine en oxygène ainsi que le mouvement des yeux.

Aux États-Unis, une équipe de chercheurs de l’université de Washington s'est demandé s'il était possible de réaliser cet examen fastidieux avec un simple smartphone ? Elle a ainsi développé une application mobile pour smartphones Android capable de détecter l’apnée du sommeil sans aucun contact avec la personne. Baptisée ApneaApp, cette application fonctionne à la manière du sonar dont la chauve-souris se sert pour se guider dans l’obscurité. L’application émet des ondes ultrasonores depuis le haut-parleur du smartphone qui rebondissent sur le corps et sont récupérées par le microphone du mobile. Les ondes réfléchissent les mouvements abdominaux liés à la respiration, les mouvements des jambes et du reste du corps.

D’après:

http://www.futura-sciences.com/magazines/high-tech/infos/actu/d/smartphone-application-mobile-detecte-apnee-sommeil-58074/#xtor=EPR-17-%5BQUOTIDIENNE%5D-20150504-%5BACTU-Une-application-mobile-qui-detecte-l-apnee-du-sommeil%5D

1 MAI 2015 HAPPY WORKERS DAY

2015-05-01T12:58:00.000-01:00

Les particules de diesel s'attaquent au fonctionnement du foie

2015-04-28T15:59:00.001-01:00

Image from:

http://rs.ksu.edu.sa/wp-content/uploads/2013/11/13842586222661864001.jpg

Gare au diesel ! Ses particules fines sont non seulement toxiques pour les poumons mais elles sont aussi capables de traverser la barrière pulmonaire et de s’attaquer à d’autres organes. Il avait en effet déjà été montré que ces particules modifient la fonction de certaines enzymeshépatiques. Une nouvelle étude montre cette fois qu’elles peuvent également altérer la fonction de détoxification du foie, c’est-à-dire sa capacité à trier et éliminer les déchets toxiques pour l’organisme.

Les chercheurs à l’origine de cette découverte (unité Inserm 1085, institut de recherche en Santé, environnement et travail, à Rennes) ont travaillé in vitro, sur des cellules de foie (hépatocytes) en culture. Ils les ont exposées à un extrait de particules issues de la combustion d'un moteur diesel (DEP, Diesel exhaust particles) à des doses équivalentes à celles inhalées par un individu vivant dans un milieu pollué. Les chercheurs ont ensuite mesuré le niveau d’expression et l’activité de plusieurs transporteurs présents à la surface des cellules. Leurs résultats paraissent dans la revue Plos One.

Ces transporteurs hépatiques assurent le passage de molécules circulant dans le sang vers l’intérieur du foie. La bile conduit ensuite à l’élimination de ces substances. L’ensemble du système permet à l’organisme de se débarrasser des déchets naturels produits par les cellules, de médicaments ou de drogues. Or, les auteurs ont constaté que les DEP réduisent l’expression degènes codant pour ces transporteurs et bloquent l’activité de plusieurs d’entre eux. Le phénomène s’observe lorsque les cellules sont exposées à de faibles doses de particules.

Lire la suite à ..

http://www.futura-sciences.com/magazines/sante/infos/actu/d/medecine-particules-diesel-attaquent-fonctionnement-foie-57943/#xtor=EPR-20-%5BHEBDO%5D-20150428-%5BACTU-Les-particules-de-diesel-s-attaquent-au-fonctionnement-du-foie%5D

Li-fi protocol allows use Internet at the speed of light

2015-04-24T16:11:00.000-01:00

image from :

http://technozed.com/wp-content/uploads/2014/09/lifi.jpg

Sisoft Company in Mexico has developed a technology that can illuminate a large work space, an auditorium or an office, while providing full mobile Internet to every device that comes into the range of the light spectrum.

The Mexican group managed to transmit audio, video and Internet across the spectrum of light emitted by LED lamps. This new technology, called Li-Fi or light fidelity, is presented as an alternative to Wi-Fi because it will maximize the original provided speed of the internet to offer safer data transfer and a transfer rate of up to 10 gigabytes per second.

The Li-Fi device circulates data via LEDs that emit an intermittent flicker at a speed imperceptible to the human eye. "As Wi-Fi uses cables to spread our connections, wireless transmission Li-Fi uses LED lamps that emit high brightness light," said Arturo Campos Fentanes, CEO of Sisoft in Mexico.

Another advantage in comparison to Wi-Fi is that there is no way to hack the signal since the internet is transmitted by light, there is no way to "steal it." Furthermore, it can be installed in hospitals areas that use radiation apparatus and generally block or distort internet signal, Campos Fentanes said.

With this new technology expansion through the market is seeked, with lower costs and a service increased by five thousand percent internet speed. Currently in Mexico the highest transfer rate is 200 megabytes per second. Just to get an idea, with Li-Fi you could quickly download an entire HD movie in just 45 seconds.

Also known as visible light communications (VLC), this technology began with an internet speed of two Gigabits per second, but Sisoft along with researchers from the Autonomous Technological Institute of Mexico (ITAM) adapted the system to be multiplied five times.

Campos Fentanes explained that the first experiments were conducted with audio, in which a cable is connected via 3.5 mm audio Jack from a smartphone to a protoboard table to transform the auditory signal in optical waves. That way a special emitter transmits data across the spectrum of light generated by an LED lamp and is captured by a receptor located in a speaker that reproduces sound.

For wireless internet transmission, the mechanics is similar. The station developed by Sisoft of Mexico stands above the router device that distributes the internet signal and a lamp-LED is incorporated to maximize the speed of data transfer. Light will emulate an antenna, but only the electronic apparatus that has the receptor for the "optical audio" signal and is inside the range of the halo of light will have a connection.

Read more from:

http://www.sciencedaily.com/releases/2014/07/140713155423.htm

Yale Engineers Design Metallic Glass Nanostructures of Tunable Shape

2015-04-22T18:43:00.000-01:00

Engineers from Yale University have developed a unique method for designing metallic glass nanostructures of tunable shape and composition, enabling the fabrication of an array of new materials.

Metallic glass, a class of materials that offers both pliability and strength, is poised for a friendly takeover of the chemical landscape.

Yale University engineers have found a unique method for designing metallic glass nanostructures across a wide range of chemicals. The process will enable the fabrication of an array of new materials, with applications for everything from fuel cells to biological implants.

“It’s a huge step for nanofabrication,” said Jan Schroers, professor of mechanical engineering and materials science at Yale, and co-author of a paper published online this week in the journal Nature Communications. “You really now have the entire toolbox to change how you make these glasses for other chemistries.”

Schroers and his team at Yale have spent years refining processes for designing metallic glass nanostructures — complex, multicomponent alloys that are constructed at the nano scale — within a limited number of alloy systems. Those materials can be molded much like plastic and already are being used in a variety of manufacturing applications, from watch parts to phone casings.

Read More From:

http://scitechdaily.com/yale-engineers-design-metallic-glass-nanostructures-of-tunable-shape/

Des plantes contre 6 maux.

2015-04-20T11:51:00.000-01:00

image from:

http://www.letudiant.fr/static/uploads/mediatheque/TRD_TRD/1/7/83017-fotolia-40265375-s-_x450.jpg

La phytothérapie, utilisée depuis des siècles, signifie « soigner par les plantes ». Aujourd'hui, de plus en plus d’études confirment les propriétés médicinales de certaines plantes. C'est pourquoi, PasseportSanté vous propose de découvrir 6 maux du quotidien à soigner au naturel.

La fatigue

Pour lutter contre la fatigue qui peut survenir au cours de la journée, l’Organisation Mondiale de la Santé (OMS) reconnaît l’usage du ginseng qui permettrait de stimuler les fonctions cognitives. Cette plante médicinale originaire d’Asie est couramment utilisée pour stimuler l’organisme des personnes fatiguées, pour rétablir la capacité de travail physique et de concentration intellectuelle et pour aider les convalescents à reprendre des forces. L’OMS recommande de privilégier la consommation de ginseng en matinée pour ne pas susciter de troubles du sommeil. ..

Quantum cryptography at the speed of light: Researchers design first all-photonic repeaters

2015-04-16T07:21:00.001-01:00

Image from:

http://www.iec.ch/etech/2013/etech_0513/pic_tech/tech-3_graphic_lrg.jpg

Summary:

Engineers bring perfectly secure information exchanges one step to reality. They have now designed the first all-photonic quantum repeaters -- protocols that ensure data can be carried reliably and securely across longer distances when using quantum cryptography.

Thanks to new research from a team of University of Toronto engineers, these types of perfectly secure information exchanges are one step closer to reality. Published this week in Nature Communications, researchers have designed the first all-photonic quantum repeaters -- protocols that ensure data can be carried reliably and securely across longer distances when using quantum cryptography.

Communication that uses quantum cryptography exploits the laws of quantum mechanics to relay information from one user to another. Coded in the quantum states of photons, this exchange is so secure that breaking it is nearly impossible. But sending photons long distances over fibres is easier said than done -- more than 90 per cent of photons are lost over distances greater than 50 kilometres, severely limiting the range of quantum communication.

To extend the range, much research has focused on developing 'quantum repeaters' to give photons a "boost" and reduce loss. These repeaters acted like mini quantum computers, storing the entangled photons and relaying their signals down the fibres -- they needed to be kept at cool temperatures and had low repeat rates, making them inconvenient and slow.

These new all-photonic quantum repeaters from engineers at U of T relay photons over long distances using photons only, without the demanding requirements of matter quantum memories or an interface between matter and light at all.

read more from:

http://www.sciencedaily.com/releases/2015/04/150415092839.htm

Marijuana component fights epilepsy

2015-04-14T11:15:00.000-01:00

A buzz-free component of marijuana can benefit epilepsy patients who have particularly severe seizures, a new study suggests. Taking an extract of the cannabis compound cannabidiol substantially cut the patients’ number of seizures over nearly three months.

Cannabidiol seems to mitigate the psychoactive effect of THC, the main euphoria-inducing chemical in cannabis. But cannabidiol also has antioxidant and anti-inflammatory effects that earlier work suggested could benefit people with multiple sclerosis and Crohn’s disease (SN: 6/19/2010, p. 16).

The new study followed 137 epilepsy patients, with a median age of 11, who had seizures that had resisted treatment. Each received cannabidiol daily in liquid form. After 12 weeks, the average number of seizures dropped by about half.

Up to one-fifth of patients reported some diarrhea, drowsiness, fatigue or loss of appetite, and 12 people stopped taking the compound because of side effects. The full findings will be reported April 22 at a meeting of the American Academy of Neurology by neurologist Orrin Devinsky of New York University Langone Medical Center. ..

NASA Missions are Finding Water in Surprising Places

2015-04-11T16:09:00.001-01:00

As NASA scientists explore our solar system and search for new worlds, they are finding water in surprising places. Water is but one piece of our search for habitable planets and life beyond Earth, yet it links many seemingly unrelated worlds in surprising ways.

“NASA science activities have provided a wave of amazing findings related to water in recent years that inspire us to continue investigating our origins and the fascinating possibilities for other worlds, and life, in the universe,” said Ellen Stofan, chief scientist for the agency. “In our lifetime, we may very well finally answer whether we are alone in the solar system and beyond.”

The chemical elements in water, hydrogen and oxygen, are some of the most abundant elements in the universe. Astronomers see the signature of water in giant molecular clouds between the stars, in disks of material that represent newborn planetary systems, and in the atmospheres of giant planets orbiting other stars.

There are several worlds thought to possess liquid water beneath their surfaces, and many more that have water in the form of ice or vapor. Water is found in primitive bodies like comets and asteroids, and dwarf planets like Ceres. The atmospheres and interiors of the four giant planets — Jupiter, Saturn, Uranus and Neptune — are thought to contain enormous quantities of the wet stuff, and their moons and rings have substantial water ice.

Perhaps the most surprising water worlds are the five icy moons of Jupiter and Saturn that show strong evidence of oceans beneath their surfaces: Ganymede, Europa and Callisto at Jupiter, and Enceladus and Titan at Saturn.

How does 3D printing work?

2015-04-10T18:08:00.000-01:00

3D printing refers to the actual creation of real-world goods or models.

You can download more than 100,000 free designs, create your own design using 3D creation software, or scan an existing object into a model with a 3D scanner. If you intend to create your own designs, check out our 3D Creation section.

The 3D printer then turns this model file into a real object by extruding plastic layer by
layer.

Read more From:

http://www.dynamism.com/guide-to-3d-printing