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Social networking sites misrepresents the real world, computer scientists warn

Social networking sites like Twitter, Facebook or Pinterest, are populated by a very narrow section of society, scientists warn

Twitter
© Alamy
Twitter trends do not represent what the public actually cares about, scientists warn.
Social networking sites like Twitter and Facebook should not be used to gauge human behaviour or trends because they are too biased, scientists have warned.

Increasingly, social researchers and media organisations use sites to glean information about public views and interests. But computer scientists at McGill University in Montreal and Carnegie Mellon University in Pittsburgh warn that the data omits the opinion of large portions of the population who are either under-represented, or who choose not to engage in social media.

They claim the sites 'misrepresent the real world.'

One of the major problems with sites like Twitter, Pinterest or Facebook is 'population bias' where platforms are populated by a very narrow section of society.

Latest figures on Twitter suggest that just five per cent of over 65s use the platform compared with 35 per cent for those aged 18-29. Similarly far more men use the social networking site than women.

Instagram has a particular appeal to younger adults, urban dwellers, and non-whites.
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Making fuel out of thin air

Fuel Cells
© Manchester University
The discovery of how to filter hydrogen ions through graphene could change the future of fuel cells.
In a discovery that experts say could revolutionise fuel cell technology, scientists have found that graphene, the world's thinnest, strongest and most impermeable material, can allow protons to pass through it.

The new discovery reported in the journal Nature raises the possibility that graphene membranes could one day be used to "sieve" hydrogen gas directly from the atmosphere to generate electricity.

"We are very excited about this result because it opens a whole new area of promising applications for graphene in clean energy harvesting and hydrogen-based technologies," says study co-author Marcelo Lozada-Hidalgo of Manchester University.

Graphene was first isolated in 2004 by the leader of this study, Professor Andre Geim who, with fellow researchers was awarded a Nobel Prize in 2010 for the work.

At just one atom thick graphene is renowned for being the thinnest material on Earth.

It is 200 times stronger than steel, and impermeable to all gases and liquids, giving it the potential for a range of uses such as corrosion-proof coatings, impermeable packaging and even super-thin condoms.
Galaxy

Star Trek-like invisible shield found thousands of miles above Earth puzzles scientists

© Andy Kale, University of Alberta
Scientists have discovered an invisible shield roughly 7,200 miles above Earth.
A team led by the University of Colorado Boulder has discovered an invisible shield some 7,200 miles above Earth that blocks so-called "killer electrons," which whip around the planet at near-light speed and have been known to threaten astronauts, fry satellites and degrade space systems during intense solar storms.

The barrier to the particle motion was discovered in the Van Allen radiation belts, two doughnut-shaped rings above Earth that are filled with high-energy electrons and protons, said Distinguished Professor Daniel Baker, director of CU-Boulder's Laboratory for Atmospheric and Space Physics (LASP). Held in place by Earth's magnetic field, the Van Allen radiation belts periodically swell and shrink in response to incoming energy disturbances from the sun.

As the first significant discovery of the space age, the Van Allen radiation belts were detected in 1958 by Professor James Van Allen and his team at the University of Iowa and were found to be comprised of an inner and outer belt extending up to 25,000 miles above Earth's surface. In 2013, Baker - who received his doctorate under Van Allen - led a team that used the twin Van Allen Probes launched by NASA in 2012 to discover a third, transient "storage ring" between the inner and outer Van Allen radiation belts that seems to come and go with the intensity of space weather.

The latest mystery revolves around an "extremely sharp" boundary at the inner edge of the outer belt at roughly 7,200 miles in altitude that appears to block the ultrafast electrons from breeching the shield and moving deeper towards Earth's atmosphere.

"It's almost like theses electrons are running into a glass wall in space," said Baker, the study's lead author. "Somewhat like the shields created by force fields on Star Trek that were used to repel alien weapons, we are seeing an invisible shield blocking these electrons. It's an extremely puzzling phenomenon."

Comment: See Earth Changes and the Human Cosmic Connection for in depth explanations of the winning Electric Universe theory, plasma (one characteristic of which is the creation of an 'insulating bubble' around charged bodies), discharge modes and much more.

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Parasites use 'trojan horse' stealth tactics to suppress immune systems

Illustration of parasitic worm
© Credit: © 3drenderings / Fotolia
Illustration of parasitic worm (stock image). Scientists have shown that parasites are able to secrete tiny sealed packages of genetic material into the cells of their victims, in order to suppress the immune response to infection.

Parasites use Trojan horse subterfuge to suppress the immunity of their victims when causing infection, according to a study.


The finding, which shows a new trick parasites can play, paves the way to possible treatments for infectious diseases and allergies.

Scientists have shown that parasites are able to secrete tiny sealed packages of genetic material into the cells of their victims, in order to suppress the immune response to infection.

The packages, known as vesicles, mimic those that are produced naturally in most organisms to carry out everyday functions such as transporting nutrients and chemical messages to and from cells. The parasite uses vesicles to hide its material inside a seemingly friendly exterior, like a Trojan horse.

The study, carried out on a parasite found in mice, showed that the material in the packages is able to interact with the mouse's own genes. It manipulates the cell's machinery to suppress products linked to immunity, so reducing resistance to infection.

Researchers say the discovery could inform new strategies for treating diseases caused by parasitic worms, which affect hundreds of millions of people and animals. The findings also offer a possible way to treat allergies, such as hayfever, because the immune mechanism that parasites block is also linked to allergic reactions.
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Vultures evolved an extreme gut to cope with disgusting dietary habits

© Stutterstock
Vultures have special digestive systems adapted to deal with putrid carcasses that would be toxic to many other animals.
How is it that vultures can live on a diet of carrion that would at least lead to severe food-poisoning, and more likely kill most other animals? This is the key question behind a recent collaboration between a team of international researchers from Denmark's Centre for GeoGenetics and Biological Institute at the University of Copenhagen, Aarhus University, the Technical University of Denmark, Copenhagen Zoo and the Smithsonian Institution in the USA. An "acidic" answer to this question is now published in the scientific journal Nature Communications.

When vultures eat lunch they happily strip the rotting carcasses they find back to the bone. And if, however, the animal's hide is too tough to easily pierce with their beak, they don't hesitate to enter it using other routes, among them the back entrance - so to speak: via the anus. Although their diet of meat that is both rotting and liberally contaminated with feces would likely kill most other animals, they are apparently immune to the cocktail of deadly microbes within their dinner such as Clostridia, Fuso- and Anthrax-bacteria.

"To investigate vultures' ability to survive eating this putrid cocktail, we generated DNA profiles from the community of bacteria living on the face and gut of 50 vultures from the USA. Our findings enable us to reconstruct both the similarities, and differences, between the bacteria found in turkey vultures and black vultures, distributed widely in the Western Hemisphere. Apparently something radical happens to the bacteria ingested during passage through their digestive system," says Lars Hestbjerg Hansen, a professor at Aarhus University who together with Ph.D.-student Michael Roggenbuck lead the study while he was at the University of Copenhagen.
Bug

Female termites found to clone themselves via asexual reproduction

© Wikipedia common
A soldier termite (Macrotermitinae) in the Okavango Delta.
A pair of researches with Kyoto University has found how the queen of one species of termite, Reticulitermes speratus, ensures her genetic lineage continues by creating duplicate copies of herself. In their paper published in Proceedings of the National Academy of Sciences, Toshihisa Yashiro and Kenji Matsuura describe the study they carried out that showed how queens in such colonies reproduce themselves.

Scientists have known since 2009 that R. speratus queens created fatherless offspring which became queens themselves, but until now, the mechanism by which that came about has been a mystery. In this new effort, the researchers took a new look at the structure of the eggs laid by the queen to discover the difference between future queens and ordinary termites. Close inspection revealed tiny channels through the outer lining of the eggs called micropyles. The channels serve as an entry point for sperm, which the queen deposits on the eggs (after obtaining it from a male).

Interestingly, the research pair found that the number of micropyles for any given egg appeared to be random, from one to more than thirty - the average was nine. Even more interesting was that the team soon learned that sometimes there were no micropyles at all in some eggs, which would of course mean that no sperm could enter to fertilize its contents - and the egg still matured and wound up in the creation of offspring. That offspring, because it had no DNA from a male, grew into a new queen. Such a process means that the females are fully in control of both sexual and asexual reproduction.
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Researchers identify receptors activated by odors

© Petr Kratochvil
A group of physiologists led by University of Kentucky's Tim McClintock have identified the receptors activated by two odors using a new method that tracks responses to smells in live mice.

Their research was published in the latest edition of The Journal of Neuroscience.

Using a fluorescent protein to mark nerve cells activated by odors, McClintock and his colleagues identified receptors that allow mouse nerve cells to respond to two odors: eugenol, which is a component of several spices, most notably cloves, and muscone, known as musk.

"This new method could help us understand how these receptors allow mice, and eventually humans, to detect and discriminate odors, similar to the way in which the three receptors in the retinas of our eyes allow us to discriminate colors," McClintock said. "But unlike vision and hearing, the details of how the odor receptors discriminate odors, much like color in vision or pitch in sound, are unknown."

"Before we have a medical application in mind, we must first create a roadmap for these receptors."
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Bioengineering study finds two-cell mouse embryos already talking about their future

© Victor O. Leshyk
Bioengineers at UC San Diego have determined through single-cell-RNA-sequencing that embryonic mouse cells show differences in gene expression as early as the two-cell stage of development.
Bioengineers at the University of California, San Diego have discovered that mouse embryos are contemplating their cellular fates in the earliest stages after fertilization when the embryo has only two to four cells, a discovery that could upend the scientific consensus about when embryonic cells begin differentiating into cell types. Their research, which used single-cell RNA sequencing to look at every gene in the mouse genome, was published recently in the journal Genome Research. In addition, this group published a paper on analysis of "time-course"single-cell data which is taken at precise stages of embryonic development in the journal of Proceedings of the National Academy of Sciences.

"Until recently, we haven't had the technology to look at cells this closely," said Sheng Zhong, a bioengineering professor at UC San Diego Jacobs School of Engineering, who led the research. "Using single-cell RNA-sequencing, we were able to measure every gene in the mouse genome at multiple stages of development to find differences in gene expression at precise stages."

The findings reveal cellular activity that could provide insight into where normal developmental processes break down, leading to early miscarriages and birth defects.

The researchers discovered that a handful of genes are clearly signaling to each other at the two-cell and four-cell stage, which happens within days after an egg has been fertilized by sperm and before the embryo has implanted into the uterus. Among the identified genes are several genes belonging to the WNT signaling pathway, well-known for their role in cell-cell communications.
Laptop

It's official: Automation makes us dumb and leads to 'skill fade'

cubicles
© Luci Gutiérrez
Computers are taking over the kinds of knowledge work long considered the preserve of well-educated, well-trained professionals.
Artificial intelligence has arrived. Today's computers are discerning and sharp. They can sense the environment, untangle knotty problems, make subtle judgments and learn from experience. They don't think the way we think - they're still as mindless as toothpicks - but they can replicate many of our most prized intellectual talents. Dazzled by our brilliant new machines, we've been rushing to hand them all sorts of sophisticated jobs that we used to do ourselves.

But our growing reliance on computer automation may be exacting a high price. Worrisome evidence suggests that our own intelligence is withering as we become more dependent on the artificial variety. Rather than lifting us up, smart software seems to be dumbing us down.
Telescope

Black hole loses its appetite for gassy cloud

© ESO/MPE/Marc Schartmann
This simulation shows the possible behavior of a gas cloud (G2) that has been observed approaching the black hole at the center of the Milky Way.
In a showdown of black hole versus G2 - a cloud of gas and dust - it looks like G2 won.

Recent research shows that G2 came within 30 billion kilometers of the super-massive black hole at the center of our galaxy, yet managed to escape from the gravitational pull of the black hole.

Initially, a supercomputer simulation prepared by two Lab physicists and a former postdoc more than two years ago suggested that some of G2 would survive, although its surviving mass would be torn apart, leaving it with a different shape and questionable fate.

The findings are the work of computational physicist Peter Anninos and astrophysicist Stephen Murray, both of AX division within the Weapons and Complex Integration Directorate (WCI), along with their former postdoc Chris Fragile, now an associate professor at the College of Charleston in South Carolina, and his student, Julia Wilson.

The team's simulations allowed the members to more efficiently follow the cloud's progression toward the black hole.
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