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εκπαιδευτικά και άλλα
εκπαίδευση, επιστήμες, πληροφορική, ρομποτική, αστρονομία, ιστορία, φεμινισμός, φιλοσοφία, δικαιώματα
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How trees secretly talk to each other through a fungal network, called the Wood Wide Web (WoWW)

How trees secretly talk to each other through a fungal network, called the Wood Wide Web (WoWW) | εκπαιδευτικά και άλλα | Scoop.it

Trees are talking and sharing resources right under your feet, using a fungal network nicknamed the Wood Wide Web. CrowdScience presenter Marnie Chesterton reveals how plants use the system to support their offspring, while others hijack the network to sabotage their rivals.


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Φινλανδία: Στη χώρα όπου οι άνθρωποι είναι σημαντικοί | Κόσμος | Η ΚΑΘΗΜΕΡΙΝΗ

Φινλανδία: Στη χώρα όπου οι άνθρωποι είναι σημαντικοί | Κόσμος | Η ΚΑΘΗΜΕΡΙΝΗ | εκπαιδευτικά και άλλα | Scoop.it
Εκατό χρόνια συμπληρώνονται φέτος από την ανεξαρτησία της Φινλανδίας και η άλλοτε πάμπτωχη χώρα έχει εξελιχθεί σε πρότυπο, με εξαιρετικές επιδόσεις στους τομείς της τεχνολογίας, της επιστήμης και της εκπαίδευσης. Η «Κ» επισκέφθηκε το μεγαλύτερο event startup και πρωτοπόρων τεχνολογιών στη χώρα και είδε πώς το φινλανδικό κράτος προωθεί την πρόσβαση στη μάθηση. | Ημερήσια Πολιτική και Οικονομική Εφημερίδα
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DNA Origami

DNA Origami | εκπαιδευτικά και άλλα | Scoop.it

Since DNA forms basepairs in a predictable way, by cleverly designing the sequences of several strands of DNA you can coax them to self-assemble into a particular shape.

 

Until recently, DNA origami has been constrained to two dimensional shapes like smiley faces, stars, and other things. These are entertaining, but this technology has potential applications besides aesthetic. Maybe one day we can build containers for drugs using DNA origami that carry medicine to particular cells, say chemotherapy drugs to cancer cells while sparing healthy cells from the same fate. Maybe one can take advantage of the stability of DNA by using it to build scaffolds on which tissues or whole organs can grow. These two applications clearly require taking DNA origami into three dimensions, which is just what Dongran Han and his colleagues did. In their designs they used one long piece of ssDNA, called the scaffold, and many small pieces of ssDNA, called staples. By choosing staples carefully, they were able to contort the scaffold into a desired shape. They began by building simple concentric circles in two dimensions with the scaffold weaving in and out between the rings. They then varied the parameters of their design to build three dimensional shapes with circular cross sections. They managed to build hemispheres, spheres, ellipsoids (stretched spheres), and flasks. They called their DNA flask the "nanoflask" in reference to its nanoscale size. The pictures of these shapes shown below are transmission electron micrographs in black and white and atomic force micrographs in yellow and red. Electron microscopes use a beam of electrons instead of light to focus on objects much smaller than the wavelength of visible light. Atomic force microscopes feel their way through a sample using a tiny needle tipped with a single atom.


Via Dr. Stefan Gruenwald
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Lucy Pérez's curator insight, September 11, 2017 4:28 PM

DNA interesting dates!

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When electrons ride a wave

When electrons ride a wave | εκπαιδευτικά και άλλα | Scoop.it

Conventional electron accelerators have become an indispensable tool in modern research. The extremely bright radiation generated by synchrotrons, or free electron lasers, provides us with unique insights into matter at the atomic level. But even the smallest versions of these super microscopes are the size of a soccer field.

 

Laser plasma acceleration could offer an alternative: with a much smaller footprint and much higher peak currents it could be the basis for the next generation of compact light sources. So far, the challenge with laser accelerators has been to create a reliable and stable electron beam, which is the prerequisite for possible applications. Physicists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) have now developed a method to increase both beam stability and quality.

 

The basic principle of laser acceleration seems quite simple: A bundled, ultra-strong laser beam hits a trace of gas, which instantly creates plasma - an ionized state of matter or, in other words, a whirling mix of charged particles. The power of the light pulse pushes electrons away from their parent ions, creating a sort of bubble-like structure with a strong electric field in the plasma. This field, which the laser pulse drags behind itself like a stern wave, traps the electrons, accelerating them to nearly the speed of light. "These speedy particles allow us to generate x-rays," Dr. Arie Irman from the HZDR Institute of Radiation Physics explains the purpose of the procedure. "For instance, when we make these electron bundles collide with another laser beam, the impact generates bright, ultra-short x-ray flashes - an immensely valuable research tool for examining extreme states of matter."

 

The strength of the secondary radiation greatly depends on the particles' electrical current. The current, in turn, is mostly determined by the number of electrons fed into the process. Laser-powered acceleration therefore holds great potential, because it reaches significantly higher peak currents in comparison with the conventional method. However, as physicist Jurjen Pieter Couperus points out, the so-called beam loading effect kicks in: "These higher currents create an electric self-field strong enough to superimpose and disturb the laser-driven wave, distorting thereby the beam. The bundle is stretched out and not accelerated properly. The electrons therefore have different energies and quality levels." But in order to use them as a tool for other experiments, each beam must have the same parameters.

 

"The electrons have to be in the right place at the right time," summarizes Couperus, who is a Ph.D. candidate in Irman's team.

Together with other colleagues at the HZDR, the two researchers were the first to demonstrate how the beam loading effect can be exploited for improved beam quality. They add a bit of nitrogen to the helium at which the laser beam is usually directed. "We can control the number of electrons we feed into the process by changing the concentration of the nitrogen," Irman explains. "In our experiments, we found out that conditions are ideal at a charge of about 300 picocoulomb. Any deviation from it - if we add more or fewer electrons to the wave - results in a broader spread of energy, which impairs beam quality."


Via Mariaschnee, Dr. Stefan Gruenwald
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Time crystals may hold the key to developing quantum computers

Time crystals may hold the key to developing quantum computers | εκπαιδευτικά και άλλα | Scoop.it

Harvard physicists have created a new form of matter - dubbed a time crystal - which could offer important insights into the mysterious behavior of quantum systems.

 

Traditionally speaking, crystals - like salt, sugar or even diamonds - are simply periodic arrangements of atoms in a three-dimensional lattice.

 

Time crystals, on the other hand, take that notion of periodically-arranged atoms and add a fourth dimension, suggesting that - under certain conditions - the atoms that some materials can exhibit periodic structure across time.

 

Led by Professors of Physics Mikhail Lukin and Eugene Demler, a team consisting of post-doctoral fellows Renate Landig and Georg Kucsko, Junior Fellow Vedika Khemani, and Physics Department graduate students Soonwon Choi, Joonhee Choi and Hengyun Zhou built a quantum system using a small piece of diamond embedded with millions of atomic-scale impurities known as nitrogen-vacancy (NV) centers. They then used microwave pulses to "kick" the system out of equilibrium, causing the NV center's spins to flip at precisely-timed intervals - one of the key markers of a time crystal. The work is described in a paper published in Nature in March.

 

But the creation of a time crystal isn't significant merely because it proves the previously-only-theoretical materials can exist, Lukin said, but because they offer physicists a tantalizing window into the behavior of such out-of-equilibrium systems.

"There is now broad, ongoing work to understand the physics of non-equilibrium quantum systems," Lukin said. "This is an area that is of interest for many quantum technologies, because a quantum computer is basically a quantum system that's far away from equilibrium. It's very much at the frontier of research...and we are really just scratching the surface."

 

But while understanding such non-equlibrium systems could help lead researchers down the path to quantum computing, the technology behind time crystals may also have more near-term applications as well.



Read more at: https://phys.org/news/2017-04-physicists-crystals-key-quantum-machines.html#jCp


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Προτάσεις του Συνηγόρου του Πολίτη για την εκπαίδευση των παιδιών προσφύγων στη Λέσβο - LawNet

Προτάσεις του Συνηγόρου του Πολίτη για την εκπαίδευση των παιδιών προσφύγων στη Λέσβο - LawNet | εκπαιδευτικά και άλλα | Scoop.it
Προτάσεις του Συνηγόρου του Πολίτη για την εκπαίδευση των παιδιών προσφύγων στη Λέσβο Προτάσεις του Συνηγόρου του Πολίτη για την εκπαίδευση των παιδιών προσφύγων στη Λέσβο
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NASA has new evidence that the moons Europa and Enceladus could host life

NASA has new evidence that the moons Europa and Enceladus could host life | εκπαιδευτικά και άλλα | Scoop.it

NASA has new evidence that the most likely places to find life beyond Earth are Jupiter's moon Europa or Saturn's moon Enceladus. In terms of potential habitability, Enceladus particularly has almost all of the key ingredients for life as we know it, researchers said. New observations of these active ocean worlds in our solar system have been captured by two NASA missions and were presented in two separate studies in an announcement at NASA HQ in Washington today.

 

Using a mass spectrometer, the Cassini spacecraft detected an abundance of hydrogen molecules in water plumes rising from the "tiger stripe" fractures in Enceladus' icy surface. Saturn's sixth-largest moon is an ice-encased world with an ocean beneath. The researchers believe that the hydrogen originated from a hydrothermal reaction between the moon's ocean and its rocky core. If that is the case, the crucial chemical methane could be forming in the ocean as well.

 

"Now, Enceladus is high on the list in the solar system for showing habitable conditions," said Hunter Waite, leader of the Cassini Ion and Neutral Mass Spectrometer team at the Southwest Research Institute in San Antonio and lead author of the Enceladus study. "The presence of hydrogen established another reference point saying there is hydrothermal activity inside this body, and that's interesting because we know in our own oceans, those are very important places that are teeming with life, and they are probably one of the earliest places where life happened on Earth."

 

Additionally, the Hubble Space Telescope showed a water plume erupting on the warmest part of the surface of Europa, one of Jupiter's moons with an icy crust over a salty liquid water ocean containing twice as much water as Earth's seas. This is the second time a plume has been observed in this exact spot, which has researchers excited that it could prove to be a feature on the surface.

 

"This is significant, because the rest of the planet isn't easy to predict or understand, and it's happening for the second time in the warmest spot," said Britney Schmidt, second author on the Europa study.


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100-eyed parasitic insect surprises scientists

100-eyed parasitic insect surprises scientists | εκπαιδευτικά και άλλα | Scoop.it
The extraordinary raspberry-like eyes of a tiny parasitic insect have been described for the first time.

 

When Xenos peckii twisted-wing parasite males emerge as adults from within the body of the hapless wasp that served as their incubator, the race is on. With an adult lifetime spanning just a few hours, the male insects have to locate a female and mate before their time is up. And the challenge of locating a female mate – which is barely more than a fleshy bag of eggs with no eyes or limbs – is particularly problematic. Concealed within the body of her own host, only the female’s head and mating channel protrude from the surface.

 

Despite their short lives and singleminded mission, the males are equipped with extraordinarily sophisticated hybrid eyes – composed of up to 50 micro-eyes, each equipped with a lens that projects a minute image onto a mini-retina of ∼100 photoreceptors. However, it was unclear whether these extraordinary creatures have color vision.

 

According to Elke Buschbeck, from the University of Cincinnati, USA, some evidence suggested that the nocturnal males may lack color vision, but with the jury still out, Buschbeck and her colleagues Marisano James, Sri Nandamuri and Aaron Stahl embarked on a study to discover whether the insects’ extraordinary eyes include the basic equipment for color vision.

 

Having stumbled across a fertilized X. peckii female during the summer and nurtured the offspring in northern paper wasps until the adult males emerged, Buschbeck and her team had only 3 h to investigate the males’ eyes before they perished.

 

Cooling the insects to extend their life expectancy, Nandamuri and James then measured the electrical signals produced by the eyes in response to flashes of light ranging from ultraviolet to red wavelengths. nMeanwhile, Aaron Stahl analyzed the insect’s gene expression pattern to identify which light-sensitive opsin proteins, which are essential for color vision, are produced by the insects.

 

Impressively, the males’ responses were strongest to green light (around 539 nm), while they responded more weakly to UV light (around 346 nm). And when the team analyzed the results of Stahl’s gene expression investigation, they identified one expressed gene that could produce a green-sensitive opsin, in addition to another that could produce a UV-sensitive opsin.

 

Although the team emphasizes that these observations are not categorical proof that twisted-wing parasite (strepsipteran) males have color vision, they say, ‘the presence of distinct UV and green opsins presents the possibility that UV-green coloration could play a significant role in strepsipteran ecology, such as helping the male to find the female’.

 

And they wonder whether our own limited color vision means that we are missing one of the parasite’s key tricks: could the females be advertising their presence in their cryptic hideaways by reflecting UV light – like bright homing beacons – to attract the males during their final desperate search? ‘If so, this could help explain another aspect of the complex life cycle of these extraordinary insects’, says Buschbeck.

 

James, M., Nandamuri, S. P., Stahl, A. and Buschbeck, E. K. The unusual eyes of Xenos peckii (Strepsiptera: Xenidae) have greenand UV-sensitive photoreceptors. J. Exp. Biol. 219: 3866-3874 (2016). 10.1242/jeb.153841


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Published and unpublished notes from Srinivasa Ramanujan available online

Published and unpublished notes from Srinivasa Ramanujan available online | εκπαιδευτικά και άλλα | Scoop.it
Srinivasa Ramanujan was born in Erode, Tamilnadu, India, on 22nd December, 1887. In his all too brief life of less than 32 years he made monumental contributions to Mathematics. While some of his contributions made into Journals - proverbial tip of the iceberg - much more remain as entries in several notebooks which he kept. The published papers were brought out in 2000, Ramanujan Papers, by Prism Publishers, Bangalore. The unpublished material in the notebooks are also of great interest to Mathematicians and they are available in book form, thanks to the efforts of the Tata Institute of Fundamental Research, Mumbai, and Narosa Publishers, Delhi.
 
To commemorate his 126th birthday on 22nd December 2013, the published papers of Srinivasa Ramanujan as well as the unpublished manuscripts are made available to the world at large via the Internet. While the published papers are available in HTML, rendered using MathJax, and PDF, the manuscripts are available in DjVu format which can be easily seen on PCs via the DjVu plugin.
 

History has seldom seen a person who was so passionate, unorthodox, as well as gifted in a field, as was Srinivasa Ramanujan, the self-taught Indian genius, who made several startling discoveries in the realm of Mathematics. Despite abject poverty and lack of formal training and encouragement, Ramanujan’s love for numbers never waned. And thanks to a chance encounter and ensuing collaboration with G.H.Hardy of Cambridge, one of the most eminent mathematicians of the world, his hidden genius came to light.

 

Ramanujan went on to make thousands of discoveries with the apparent ease of experiencing and recording a series of religious epiphanies by amystic in a trance. The methods he followed are still shrouded in a veil of mystery, since he usually skipped the formal rigour (and hence made mistakes too sometimes) and relied more on leaps of intuition to arrive at sudden, surprising results.

 

The several ‘Notebooks’ left behind by Ramanujan are strewn with cryptic formulae and equations, and are still being mined by mathematicians all over the world for beautiful gems and nuggets.


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Mysterious Magnetic Field Detected in Binary Star System Epsilon Lupi

Mysterious Magnetic Field Detected in Binary Star System Epsilon Lupi | εκπαιδευτικά και άλλα | Scoop.it

Epsilon Lupi, also known as HD 136504, is a bright binary located in the southern constellation Lupus. The pair of stars is approximately 500 light years away, each have between 7 and 8 times the mass of the Sun, and combined together the pair is around 6,000 times as luminous as the Sun. Astronomers have known for many years that Epsilon Lupi is a binary system, but had no idea that the two stars had magnetic fields.


“The origin of magnetism amongst massive stars is something of a mystery and this discovery may help to shed some light on the question of why any of these stars have magnetic fields,” said Matt Shultz of Queen’s University, Canada, a team member and the lead author of a paper accepted for publication in the Monthly Notices of the Royal Astronomical Society (arXiv.org preprint).


In cool stars, such as the Sun, magnetic fields are generated by ‘dynamos’ powered by strong convection in the outer layers of the star, where hot material rises, cools and falls back. But there is essentially no convection in the envelopes of massive stars, so there is no support for a magnetic dynamo. Nevertheless, about 10 percent of massive stars have strong magnetic fields.


Two explanations have been proposed for their origin, both variants on the idea of a ‘fossil’ magnetic field — a field generated at some point in the star’s past and then locked into the star’s surface. The first hypothesis is that the magnetic field is generated while the star is being formed. A second is that the magnetic field originates in dynamos driven by the violent mixing of material when two already-formed stars in a close binary merge.


“This discovery allows us to rule out the binary merger scenario,” Shultz said. The research shows the strengths of the magnetic fields are similar in the two stars of Epsilon Lupi, however their magnetic axes are anti-aligned, with the south magnetic pole of one star pointing in approximately the same direction as the north pole of the other. It may even be that the two stars share a single magnetic field.


“We’re not sure why yet, but it probably points to something significant about how the stars are interacting with one another,” Shultz said. The stars are close enough that their magnetospheres are likely to be interacting during the whole of their orbit around each other.



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Διαδικτυακός εκφοβισμός - Βικιπαίδεια

Διαδικτυακός εκφοβισμός - Βικιπαίδεια

Ο όρος Διαδικτυακός εκφοβισμός (Cyber-bullying) αφορά τον εκφοβισμό, την απειλή, την ταπείνωση ή την παρενόχληση παιδιών, προεφήβων και εφήβων που δέχονται μέσω της χρήσης του Διαδικτύου, κινητών τηλεφώνων είτε άλλων ψηφιακών τεχνολογιών από ομηλίκους τους.


Via Lilia Moulotsiou-Vlachou, Ευη Πατ
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Brainlike Computers Are Learning From Experience

Brainlike Computers Are Learning From Experience | εκπαιδευτικά και άλλα | Scoop.it

Computers have entered the age when they are able to learn from their own mistakes, a development that is about to turn the digital world on its head.


The first commercial version of the new kind of computer chip is scheduled to be released in 2014. Not only can it automate tasks that now require painstaking programming — for example, moving a robot’s arm smoothly and efficiently — but it can also sidestep and even tolerate errors, potentially making the term “computer crash” obsolete.

 

The new computing approach, already in use by some large technology companies, is based on the biological nervous system, specifically on how neurons react to stimuli and connect with other neurons to interpret information. It allows computers to absorb new information while carrying out a task, and adjust what they do based on the changing signals.

 

In coming years, the approach will make possible a new generation of artificial intelligence systems that will perform some functions that humans do with ease: see, speak, listen, navigate, manipulate and control. That can hold enormous consequences for tasks like facial and speech recognition, navigation and planning, which are still in elementary stages and rely heavily on human programming.

 

Designers say the computing style can clear the way for robots that can safely walk and drive in the physical world, though a thinking or conscious computer, a staple of science fiction, is still far off on the digital horizon.

 

“We’re moving from engineering computing systems to something that has many of the characteristics of biological computing,” said Larry Smarr, an astrophysicist who directs the California Institute for Telecommunications and Information Technology, one of many research centers devoted to developing these new kinds of computer circuits.


Until now, the design of computers was dictated by ideas originated by the mathematicianJohn von Neumann about 65 years ago. Microprocessors perform operations at lightning speed, following instructions programmed using long strings of 1s and 0s. They generally store that information separately in what is known, colloquially, as memory, either in the processor itself, in adjacent storage chips or in higher capacity magnetic disk drives.

 

The data — for instance, temperatures for a climate model or letters for word processing — are shuttled in and out of the processor’s short-term memory while the computer carries out the programmed action. The result is then moved to its main memory.

 

The new processors consist of electronic components that can be connected by wires that mimic biological synapses. Because they are based on large groups of neuron-like elements, they are known as neuromorphic processors, a term credited to the California Institute of Technology physicist Carver Mead, who pioneered the concept in the late 1980s.

 

They are not “programmed.” Rather the connections between the circuits are “weighted” according to correlations in data that the processor has already “learned.” Those weights are then altered as data flows in to the chip, causing them to change their values and to “spike.” That generates a signal that travels to other components and, in reaction, changes the neural network, in essence programming the next actions much the same way that information alters human thoughts and actions.

 

“Instead of bringing data to computation as we do today, we can now bring computation to data,” said Dharmendra Modha, an I.B.M. computer scientist who leads the company’s cognitive computing research effort. “Sensors become the computer, and it opens up a new way to use computer chips that can be everywhere.”



Via Szabolcs Kósa, Dr. Stefan Gruenwald
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VendorFit's curator insight, December 31, 2013 3:27 PM

Artificial intelligence is the holy grail of technological achievment, creating an entity that can learn from its own mistakes and can (independently of programmer intervention) develop new routines and programs.  The New York Times claims that the first ever "learning" computer chip is to be released in 2014, an innovation that has profound consequences for the tech market.  When these devices become cheaper, this should allow for robotics and device manufacture that incorporates more detailed sensory input and can parse real objects, like faces, from background noise. 

Laura E. Mirian, PhD's curator insight, January 10, 2014 1:16 PM

The Singularity is not far away

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«Έξυπνα» ρομπότ, τα οποία μπορούν να «μαθαίνουν» - Nαυτεμπορικη

«Έξυπνα» ρομπότ, τα οποία μπορούν να «μαθαίνουν» - Nαυτεμπορικη | εκπαιδευτικά και άλλα | Scoop.it
Nαυτεμπορικη «Έξυπνα» ρομπότ, τα οποία μπορούν να «μαθαίνουν» Nαυτεμπορικη Όπως αναφέρει δημοσίευμα του BBC, το Πανεπιστήμιο του Λίνκολν έχει λάβει χρηματοδότηση ύψους 750.000 δολαρίων για να αναπτύξει το ειδικό λογισμικό «επεξεργασίας» των...
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DNA Origami

DNA Origami | εκπαιδευτικά και άλλα | Scoop.it

Since DNA forms basepairs in a predictable way, by cleverly designing the sequences of several strands of DNA you can coax them to self-assemble into a particular shape.

 

Until recently, DNA origami has been constrained to two dimensional shapes like smiley faces, stars, and other things. These are entertaining, but this technology has potential applications besides aesthetic. Maybe one day we can build containers for drugs using DNA origami that carry medicine to particular cells, say chemotherapy drugs to cancer cells while sparing healthy cells from the same fate. Maybe one can take advantage of the stability of DNA by using it to build scaffolds on which tissues or whole organs can grow. These two applications clearly require taking DNA origami into three dimensions, which is just what Dongran Han and his colleagues did. In their designs they used one long piece of ssDNA, called the scaffold, and many small pieces of ssDNA, called staples. By choosing staples carefully, they were able to contort the scaffold into a desired shape. They began by building simple concentric circles in two dimensions with the scaffold weaving in and out between the rings. They then varied the parameters of their design to build three dimensional shapes with circular cross sections. They managed to build hemispheres, spheres, ellipsoids (stretched spheres), and flasks. They called their DNA flask the "nanoflask" in reference to its nanoscale size. The pictures of these shapes shown below are transmission electron micrographs in black and white and atomic force micrographs in yellow and red. Electron microscopes use a beam of electrons instead of light to focus on objects much smaller than the wavelength of visible light. Atomic force microscopes feel their way through a sample using a tiny needle tipped with a single atom.


Via Dr. Stefan Gruenwald, Ευη Πατ
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Lucy Pérez's curator insight, September 11, 2017 4:28 PM

DNA interesting dates!

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Are we being watched? Many alien worlds could spot the Earth

Are we being watched? Many alien worlds could spot the Earth | εκπαιδευτικά και άλλα | Scoop.it

A group of scientists from Queen's University Belfast and the Max Planck Institute for solar system Research in Germany have turned exoplanet-hunting on its head, in a study that instead looks at how an alien observer might be able to detect Earth using our own methods. They find that at least nine exoplanets are ideally placed to observe transits of Earth, in a new work published in the journal Monthly Notices of the Royal Astronomical Society.

 

 

Thanks to facilities and missions such as SuperWASP and Kepler, we have now discovered thousands of planets orbiting stars other than our sun, worlds known as 'exoplanets'. The vast majority of these are found when the planets cross in front of their host stars in what are known as 'transits', which allow astronomers to see light from the host star dim slightly at regular intervals every time the planet passes between us and the distant star.

 

In the new study, the authors reverse this concept and ask, "How would an alien observer see the solar system?" They identified parts of the distant sky from where various planets in our solar system could be seen to pass in front of the sun – so-called 'transit zones'—concluding that the terrestrial planets (Mercury, Venus, Earth, and Mars) are actually much more likely to be spotted than the more distant 'Jovian' planets (Jupiter, Saturn, Uranus, and Neptune), despite their much larger size.

 

"Larger planets would naturally block out more light as they pass in front of their star", commented lead author Robert Wells, a PhD student at Queen's University Belfast. "However the more important factor is actually how close the planet is to its parent star – since the terrestrial planets are much closer to the sun than the gas giants, they'll be more likely to be seen in transit."


Via Dr. Stefan Gruenwald
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Nevermore Sithole's curator insight, September 11, 2017 8:11 AM
Are we being watched? Many alien worlds could spot the Earth
Donald Schwartz's curator insight, September 12, 2017 11:39 AM

Here's looking right back at you kid.

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Researchers analyze flocking behavior on curved surfaces

Researchers analyze flocking behavior on curved surfaces | εκπαιδευτικά και άλλα | Scoop.it

A murmuration of starlings. The phrase reads like something from literature or the title of an arthouse film. In fact, it is meant to describe the phenomenon that results when hundreds, sometimes thousands, of these birds fly in swooping, intricately coordinated patterns through the sky.

Or in more technical terms, flocking. But birds are not the only creatures that flock. Such behavior also takes place on a microscopic scale, such as when bacteria roam the folds of the gut. Yet bird or bacteria, all flocking has one prerequisite: The form of the entity must be elongated with a "head" and "tail" to align and move with neighbors in an ordered state.

 

Physicists study flocking to better understand dynamic organization at various scales, often as a way to expand their knowledge of the rapidly developing field of active matter. Case in point is a new analysis by a group of theoretical physicists, including Mark Bowick, deputy director of UC Santa Barbara's Kavli Institute for Theoretical Physics (KITP).

 

Generalizing the standard model of flocking motion to the curved surface of a sphere rather than the usual linear plane or flat three-dimensional space, Bowick's team found that instead of spreading out uniformly over the whole sphere, arrowlike agents spontaneously order into circular bands centered on the equator.

 

The team's findings appear in the journal Physical Review X.


Via Mariaschnee, Dr. Stefan Gruenwald
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Harvard Scientists Think They’ve Pinpointed The Physical Source Of Consciousness

Harvard Scientists Think They’ve Pinpointed The Physical Source Of Consciousness | εκπαιδευτικά και άλλα | Scoop.it

Μόνο μαζί μπορούμε να κάνουμε τη διαφορά! Η αλήθεια περιμένει να γίνει γνωστό.

 

Τι είναι αυτό που μας κάνει να γνωρίζει την ύπαρξή μας, και αυτό σχετίζεται με το μυαλό, τη φυσική σφαίρα, ή κάτι πιο βαθύ; Πολλοί επιστήμονες συνήθως αφορούν μόνο τη συνείδηση στο μυαλό, ταυτίζοντάς το με αυτογνωσία, ενώ άλλοι αναγνωρίζουν ότι αυτά τα στοιχεία είναι στοιχεία αλληλένδετα.

Ερευνητές στο Πανεπιστήμιο του Χάρβαρντ πιστεύουν ότι έχουν εντοπίσει τελικά τη φυσική πηγή της συνείδησης στον άνθρωπο. Η ομάδα διαπίστωσε ότι υπάρχουν τρεις συγκεκριμένες περιοχές του ανθρώπινου εγκεφάλου που φαίνεται να είναι θεμελιώδους σημασίας για τη συνείδηση.

«Για πρώτη φορά, έχουμε βρει μια σύνδεση μεταξύ της περιοχής στελέχους που συμμετέχουν στην εγρήγορση και περιοχές που εμπλέκονται στην ευαισθητοποίηση, δύο προϋποθέσεις για τη συνείδηση,» εξήγησε ο επικεφαλής της έρευνας , Michael Fox, από το Ιατρικό Κέντρο Beth Israel Deaconess στη Ιατρική Σχολή του Χάρβαρντ. «Πολλά είναι τα στοιχεία που ήρθαν όλα μαζί να επισημάνω σε αυτό το δίκτυο παίζει έναν ρόλο στην ανθρώπινη συνείδηση.»

Από την άποψη της διέγερσης, οι ερευνητές είχαν ήδη διαπιστώσει ότι είναι ρυθμίζονται από το εγκεφαλικό στέλεχος, το τμήμα του εγκεφάλου που είναι συνδεδεμένη με το νωτιαίο μυελό , η οποία ρυθμίζει τον κύκλο του ύπνου, του καρδιακού ρυθμού και της αναπνοής. Όταν σκέφτεστε για τη σχέση του νωτιαίου μυελού στο σύστημα τσάκρα και Kundalini ενέργειας, δεν είναι έκπληξη το γεγονός ότι αυτό είναι ύποπτο να είναι ένα θεμελιώδες μέρος της ανθρώπινης συνείδησης στο φυσικό σώμα.

Η συνειδητοποίηση, από την άλλη πλευρά, έχει αποδειχθεί ότι είναι πολύ πιο δύσκολο να εντοπίσει και στο παρελθόν, αν και είναι ήδη εικάζεται ότι βρίσκεται κάπου στο φλοιό, ή το εξωτερικό στρώμα του εγκεφάλου. Ωστόσο, η ομάδα του Χάρβαρντ έχει εντοπίσει δύο περιοχές φλοιού που εμφανίζονται να συνεργαστούν ουσιαστικά «τη δημιουργία συνείδησης.»

Ασθενείς 36 νοσοκομείο με εγκεφαλικό στέλεχος βλάβες συμμετείχαν στη μελέτη, 12 από τους οποίους ήταν σε κώμα. Οι επιστήμονες χαρτογραφηθεί brainstems τους, προκειμένου να καταλάβω γιατί μερικοί άνθρωποι έμειναν συνείδηση, παρά τα τραύματά τους, ενώ άλλοι έγιναν σε κωματώδη κατάσταση. Τα ευρήματά τους υποδηλώνουν ότι η ραμφικών dorsolateral καλύπτρας της γέφυρας, μια περιοχή του εγκεφαλικού στελέχους, συνδέεται με κώμα, 10 από τους 12 ασθενείς σε κώμα που υπέστησαν τραυματισμούς σε αυτόν τον τομέα.

Στη συνέχεια συνέκριναν το φλοιό σε αυτόν τον τομέα του εγκεφαλικού στελέχους και προσδιόρισε ποια μέρη συνδέθηκαν με αυτό. Βρήκαν ότι τα δύο τμήματα του φλοιού που συνδέεται με αυτό το μέρος του εγκεφαλικού στελέχους, ολοκληρώνοντας έτσι ότι θα ήθελα να είναι οι πιο πιθανές περιοχές να διαδραματίσει σημαντικό ρόλο στη συνείδηση. Η πρώτη ήταν στο αριστερό, κοιλιακό, πρόσθια νησίδα (ΑΙ), και η άλλη ήταν στο pregenual πρόσθιο φλοιό προσαγωγίου (ΡΑΟΟ).

Η ομάδα εξέτασε επίσης fMRI σαρώνει από 45 άλλους ασθενείς σε κώμα, τα οποία έδειξαν ότι οι ασθενείς που υπέστησαν κάποιο είδος τραυματισμού ή αναστάτωση μεταξύ αυτών των τριών αναπόσπαστο περιοχές του εγκεφάλου. Για τους ερευνητές, αυτό υποδηλώνει ότι αυτές οι τρεις περιοχές διαδραματίζουν θεμελιώδη ρόλο στη συνείδηση. Ίσως αυτή η μελέτη θα μας φέρει ένα βήμα πιο κοντά στην κατανόηση του γιατί οι ασθενείς σε κώμα χάσει τις αισθήσεις της ευαισθητοποίησης τους!


Via Dr. Stefan Gruenwald
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Big Data Technology – What’s Next?

Big Data Technology – What’s Next? | εκπαιδευτικά και άλλα | Scoop.it

The world is expanding and so is the data around. The concept of big data has never looked more fascinating than now. Businesses are now looking for patterns to implement big data technology directly into their business applications and software. The term has moved from being just a buzzword to one of the most essential components of a company’s IT infrastructure.

 

Organizations are taking the next step to identify the current as well as future developments in big data deployments.

Massive data sets from an ever-expanding list of sources are what define big data in the simplest way. Organizations are trying to create a culture where they can embed the technology in applications so that it can truly empower their business. Truly, big data has taken the business world by storm, but what next! How big is it going to get; will businesses using data see productivity benefits, are there any security concerns? Questions abound and so does their answers. However, differentiating between what will sustain and what will pass will save you time and most importantly, a wrong investment.

 

Since long, big data solutions, has been introduced as massive sets built around centralized data lakes. The reasons were quite simple. The data became difficult to duplicate and management was easier. In 2016 though, organizations are thinking of moving to distributed big data processing, not to mention managing multiple data location centers and multiple devices. Further, the continued growth of the Internet of Things is increasingly going to affect the deployment of distributed data processing frameworks.

 

The ever-expanding list of resources continues generating larger and larger volumes of data. There are a lot of data and there is going to be more. Data-driven companies like Google are stressing on data analysis and how it must be grounded in sound values and practices.

 

Terabytes, petabytes, or exabytes - big data means huge amounts of data getting transferred between applications. The consistent back and forth of information is creating huge security concerns. Intrusions are detected on a daily basis and what’s worse is organizations are keeping security as their second or third priority. Hackers can breach any database if your security system gets easily defeated.

 

Organizations with weak protection solutions will end up being victims of thousands of hackers out there. Get a top-notch anti-malware software program that will safeguard your perimeter and it won’t be pregnable.

 

Experts debate when it comes to quality of data. According to them, big isn’t necessary whatsoever and business doesn’t use even a fraction of the data they have access to. The idea is moving from big to fast and actionable data that answer questions and produces effective uses of the data.

 

Big data is going to get bigger no matter what. Don’t get left behind and adopt it as soon as possible. For effective data management and protection from intrusion, make sure you are securing your enterprise with top performance anti-malware solutions. If big data is expanding, then so has to be the scale, speed, security and integration requirements of your organization.


Via Fernando Gil, Dr. Stefan Gruenwald
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Inside a Hard Disc Drive

Λειτουργία Σκληρού Δίσκου. Ένα πολύ καλό βίντεο. (Ρυθμίσεις, Αυτόματη Μετάφραση, επιλέξτε Ελληνικά).  Για όσους επιθυμούν, περισσότερες χρήσιμες πληροφορίες μπορούν να διαβάσουν στον σύνδεσμο: http://electricalnews.gr/texnologia/ypologistes/hardware/item/536-skliros-diskos-hdd


Via Lilia Moulotsiou-Vlachou
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Ramanujan and The world of Pi

Ramanujan and The world of Pi | εκπαιδευτικά και άλλα | Scoop.it

Ramanujan was very passionate about pi. Many of his results involve this favorite mathematical constant.


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Theory provides roadmap in quest for quark soup 'critical point'

Theory provides roadmap in quest for quark soup 'critical point' | εκπαιδευτικά και άλλα | Scoop.it

Thanks to a new development in nuclear physics theory, scientists exploring expanding fireballs that mimic the early universe have new signs to look for as they map out the transition from primordial plasma to matter as we know it. The theory work, described in a paper recently published as an Editor's Suggestion in Physical Review Letters (PRL), identifies key patterns that would be proof of the existence of a so-called "critical point" in the transition among different phases of nuclear matter. Like the freezing and boiling points that delineate various phases of water -- liquid, solid ice, and steam -- the points nuclear physicists seek to identify will help them understand fundamental properties of the fabric of our universe.

 

Nuclear physicists create the fireballs by colliding ordinary nuclei -- made of protons and neutrons -- in an "atom smasher" called the Relativistic Heavy Ion Collider (RHIC), a U.S. Department of Energy Office of Science User Facility at Brookhaven National Laboratory. The subatomic smashups generate temperatures measuring trillions of degrees, hot enough to "melt" the protons and neutrons and release their inner building blocks -- quarks and gluons. The collider essentially turns back the clock to recreate the "quark-gluon plasma" (QGP) that existed just after the Big Bang. By tracking the particles that emerge from the fireballs, scientists can learn about nuclear phase transitions -- both the melting and how the quarks and gluons "freeze out" as they did at the dawn of time to form the visible matter of today's world.

 

"We want to understand the properties of QGP," said nuclear theorist Raju Venugopalan, one of the authors on the new paper. "We don't know how those properties might be used, but 100 years ago, we didn't know how we'd use the collective properties of electrons, which now form the basis of almost all of our technologies. Back then, electrons were just as exotic as the quarks and gluons are now."


Via Dr. Stefan Gruenwald
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Astronomers Pinpoint the Location of Multiple Weird Radio Bursts Beyond Our Galaxy

Astronomers Pinpoint the Location of Multiple Weird Radio Bursts Beyond Our Galaxy | εκπαιδευτικά και άλλα | Scoop.it

Fast radio bursts, powerful pulses of radio energy of unknown cosmic origin, are a source of endless fascination to astronomers and alien conspiracy theory fodder to everybody else. But while most FRBs discovered to date are one-off events—a single chirp in the interstellar void, if you will—these phenomena got more interesting last year when astronomers discovered the very first FRB signal that repeats. Now, they’ve pinpointed its location.

 

FRB 121102, the only repeating fast radio burst know to science, is located over three billion light years away, in a dwarf galaxy a thousand times dimmer than the Milky Way, according to new research published today in Nature. Not only does the new analysis confirm that mysterious radio bursts emanate from a source far beyond our galaxy, zeroing in on their location means we can start unraveling what exactly that source is.

 

All we know at this point is that FRBs are coming from something powerful. “These radio flashes must have enormous amounts of energy to be visible from over 3 billion light-years away,” Cornell astronomer and lead study author Shami Chatterjee said in a statement.

 

“I think this is a really big deal, and I’m really excited about the result,” said Peter Williams, an astronomer at Harvard’s Center for Astrophysics who was not involved with the study.

 

Over the past decade, astronomers have cataloged more than a dozen FRBs, seemingly random flashes of radio energy that appear in the sky at farflung locations and then disappear. FRB 121102 was first spotted in 2012 at the Arecibo Observatory in Puerto Rico, one of the world’s most powerful radio telescopes. But unlike earlier FRBs, 1211102 wasn’t just a flash in the pan: follow-up observations in 2015 revealed ten additional radio bursts emanating from the same region of space. “This unambiguously identifies FRB 121102 as repeating,” astronomers wrote of the discovery last year in Nature. 


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Cassini finds global ocean in Saturn's moon Enceladus

Cassini finds global ocean in Saturn's moon Enceladus | εκπαιδευτικά και άλλα | Scoop.it
A global ocean lies beneath the icy crust of Saturn's geologically active moon Enceladus, according to new research using data from NASA's Cassini mission.

Researchers found the magnitude of the moon's very slight wobble, as it orbits Saturn, can only be accounted for if its outer ice shell is not frozen solid to its interior, meaning a global ocean must be present.

The finding implies the fine spray of water vapor, icy particles and simple organic molecules Cassini has observed coming from fractures near the moon's south pole is being fed by this vast liquid water reservoir. The research is presented in a paper published online this week in the journal Icarus.

Previous analysis of Cassini data suggested the presence of a lens-shaped body of water, or sea, underlying the moon's south polar region. However, gravity data collected during the spacecraft's several close passes over the south polar region lent support to the possibility the sea might be global. The new results -- derived using an independent line of evidence based on Cassini's images -- confirm this to be the case.

"This was a hard problem that required years of observations, and calculations involving a diverse collection of disciplines, but we are confident we finally got it right," said Peter Thomas, a Cassini imaging team member at Cornell University, Ithaca, New York, and lead author of the paper.

Cassini scientists analyzed more than seven years' worth of images of Enceladus taken by the spacecraft, which has been orbiting Saturn since mid-2004. They carefully mapped the positions of features on Enceladus -- mostly craters -- across hundreds of images, in order to measure changes in the moon's rotation with extreme precision.

As a result, they found Enceladus has a tiny, but measurable wobble as it orbits Saturn. Because the icy moon is not perfectly spherical -- and because it goes slightly faster and slower during different portions of its orbit around Saturn -- the giant planet subtly rocks Enceladus back and forth as it rotates.

The team plugged their measurement of the wobble, called a libration, into different models for how Enceladus might be arranged on the inside, including ones in which the moon was frozen from surface to core.

"If the surface and core were rigidly connected, the core would provide so much dead weight the wobble would be far smaller than we observe it to be," said Matthew Tiscareno, a Cassini participating scientist at the SETI Institute, Mountain View, California, and a co-author of the paper. "This proves that there must be a global layer of liquid separating the surface from the core."

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Διαδικτυακός εκφοβισμός - Βικιπαίδεια

Διαδικτυακός εκφοβισμός - Βικιπαίδεια

Ο όρος Διαδικτυακός εκφοβισμός (Cyber-bullying) αφορά τον εκφοβισμό, την απειλή, την ταπείνωση ή την παρενόχληση παιδιών, προεφήβων και εφήβων που δέχονται μέσω της χρήσης του Διαδικτύου, κινητών τηλεφώνων είτε άλλων ψηφιακών τεχνολογιών από ομηλίκους τους.


Via Lilia Moulotsiou-Vlachou
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Όταν η εκπαίδευση δεν είναι μόνο νούμερα

Όταν η εκπαίδευση δεν είναι μόνο νούμερα | εκπαιδευτικά και άλλα | Scoop.it
Η σχολική χρονιά ξεκίνησε με ελλείψεις στα σχολεία, και συνεχίζεται δυστυχώς με ελλείψεις.
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