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Instant Genius after Head Trauma [Video]

Scientific American News - 1 hour 18 min ago
Savantism can be acquired after a stroke or a blow to the head. A leading expert explains the various forms of the condition

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Happy Birthday, Chandra X-Ray Observatory

Popular Science News - 1 hour 33 min ago

Supernova Remnant G292.0+1.8 One of four new images from Chandra. NASA/CXC/SAO

The Space Shuttle Columbia carried the Chandra X-ray Observatory into space on July 23, 1999. To commemorate the telescope's quinceañera, NASA has released four beautiful new images of supernova remnants, processed from Chandra's readings, that showcase the observatory's capabilities.

One of the agency's "Great Observatories" along with the Hubble and Spitzer space telescopes, Chandra does not take photographs, but rather makes detects X-ray emissions from "hot and energetic" areas of the universe, which can be rendered into images. The rig is named in honor of Nobel laureate astrophysicist Subrahmanyan "Chandra" Chandrasekhar (1910-1995). Since "chandra" also means both "moon" and "shining" in Sanskrit, the name seems especially appropriate.

NASA held an online hangout-birthday party on July 22 – which you can watch here – with Chandra scientists Steve O'Dell, Harvey Tananbaum, Julie Hlavacek-Larrondo and Scott Wolk. They chatted with the public about highlights of the mission and showed off amazing Chandra images.

View the gallery here.








Leishmania Parasite: Deadly For Humans, Good For Flies

Popular Science News - 2 hours 56 min ago

This is a sand fly, an insect which spreads leishmaniasis. Rod Dillon

No human would be inclined to think favorably of leishmaniasis, caused by a parasite spread by sand flies, which infects about 12 million people worldwide and kills 20,000 to 30,000 per year

Leishmaniasis comes in two basic forms, cutaneous and visceral. The second is more serious, attacking the internal organs, and can lead to death if it's not treated. But cutaneous leishmaniasis is more visible, causing large (and egregious, unsightly) skin sores and lesion that can leave behind nasty scars. The cutaneous variety can also spread to the body's mucous membranes, creating sores in the sinuses and mouth--which can end up destroying them. Leishmaniasis is found in 90 countries, mostly in the tropics, from Latin America to Africa, the Middle East and South Asia. "Collectively the leishmaniases present a major global health problem, and are the second biggest parasitic killers worldwide after Malaria," Owens said. 

But it turns out that this "parasite" may actually be beneficial for the flies that carry it, by helping them to fight off infection from a different type of pathogen, new research shows.

It was previously known that various species of the Leishmania protozoa can shorten the lifespan of sand flies, especially if they are stressed (hey, flies get stressed too)--but according to the new study, published in the journal Parasites and Vectors, nobody had looked to see if the microbe might have beneficial effects for the insect. But that's just what a team of Brazilian and British researchers has done. When they exposed sand flies to a form of Leishmania protozoa found throughout Latin America, then exposed the insects to pathogenic bacteria, many more of the protozoa-carrying flies survived. In fact, at least five times more of the Leishmania-carrying flies lived after exposure to the bacterium (known as Serratia marcescens), compared to flies free of the protozoa.

The Leishmania parasite "works as a kind of probiotic and reduces the mortality of the fly," said study co-author Rod Dillon, a researcher at Lancaster University in the United Kingdom. 

"This is very interesting, as it is suggestive that similar mechanisms are operating here in the sandfly, as occurs in humans--i.e. that the ['good'] bacteria that inhabit your gut can protect you from pathogenic bacteria," said Ben Owens, an immunologist at the University of Oxford, who wasn't involved in the study. But in this case the Leishmania "is acting as a 'good' bug.'"

There are other instances of "parasites" having some beneficial effects for their hosts. For example, some helminths, or worms, can help regulate the immune system of animals that carry them, Owens told Popular Science. In fact, various helminths have potential to treat human autoimmune and gastrointestinal disorders like ulcerative colitis and Crohn's disease.

But not everybody is convinced. “I think it is really a stretch to say that the parasite has evolved to provide this protection,” George Dimopoulos, a professor of molecular microbiology and immunology at the Johns Hopkins Bloomberg School of Public Health in Baltimore told The Scientist. “It’s more likely that Leishmania, as with all parasites that are transmitted by vectors, will turn on the sand fly’s immune system, which in turn is going to provide some level of protection against any other type of microorganism.” He added: “It’s not something that is necessarily specific to [Leishmania]."

The team had originally been looking to see whether they might be able to halt the spread of leishmaniasis by exposing sand flies to bacteria (to kill the flies, but perhaps also make the flies less likely to carry the protozoa). But exposing the flies to this bacterium, could ironically do quite the opposite. "Sand flies not carrying Leishmania may succumb more rapidly to the biological control agent and this would lead to the development of a wild sand fly population containing an increased proportion of the surviving flies carrying the human disease", the authors wrote. A scary thought.

There is no vaccine for leishmaniasis, and it can be difficult to treat--the standard therapy to date usually involves injecting patients with an antimony-containing compound that can have bad side effects. But for sand flies, Leishmania is not the horror it is for humans. 








An Animated Avatar Could Screen Humans For National Security

Popular Science News - 3 hours 33 min ago

The Avatar Tested for National Security Interviews NCAA

When the paperwork at your doctor's office asks you how much alcohol you drink, do you write down the truth? Would you be more likely to tell the truth if an animated head interviewed you instead? One team of U.S. military psychologists is betting you would.

In a new study, researchers from the U.S. National Center for Credibility Assessment have determined folks are more likely to say more about their alcohol use and mental health history to an avatar on a computer screen than on a questionnaire, Vice's Motherboard reports. People's responses to questions about drug use and criminal history were about the same on questionnaires as to the avatar.

The NCCA software works with a decision tree that tells it what to say in response to people's answers, Motherboard explains. Its success with getting people to tell the truth has prompted the center to recommend avatars replace human interviewers during a preliminary step in earning national security clearance. The avatars would save the U.S. government time and money, the study authors write.

This isn't the first time scientists have thought of using computer-graphic heads to interview people, although it's the first I've heard of such interviews in connection with national security. Other researchers have focused on making software that screens people for depression. The software uses avatars to ask people questions and algorithms to analyze people's verbal and non-verbal cues while they're answering. From Motherboard's report, it's not clear to what extent the National Center for Credibility Assessment's software is able to analyze interviewees' non-verbal reactions… if it can't yet, that would surely be a powerful thing to add.

[Vice Motherboard]








Why DARPA Wants An Experimental Spaceplane

Popular Science News - 4 hours 19 min ago

Artist's Concept for an Experimental Spaceplane DARPA

So DARPA wants a reusable spaceplane. I mean, who doesn't? For decades, space experts have tried to design quick-turnover, reusable launch systems. So far, however, no one has made one that works. "There really isn't any kind of vehicle today that does exactly what they're asking people to do," Micah Walter-Range, director of research and analysis at the Space Foundation, tells Popular Science. "You can certainly compare it to existing vehicles, but it seems to be a new class." 

Here's how the dream goes: Our fictional rocket would blast off at hypersonic speeds. Once it reached the right altitude, it would release any upper stages (and payload) it might have. Then it would turn back toward the Earth and land gently someplace where engineers would be able to fetch it, polish it up, and stick it back on the launch pad. Theoretically, reusable rockets should cut the costs of launches enough to open up space to more groups, such as students and startups, and ease NASA's financial burdens.

It'd be like having a jumbo jet for getting to space. Just load, unload, and repeat.

A few different groups have been working toward this goal recently. Last week, the U.S. Defense Advanced Research Projects Agency announced it awarded three teams contracts to make initial designs for just such a reusable small-satellite shuttle. One team is led by the Boeing Company, working with Blue Origin; Masten Space Systems, working with XCOR Aerospace, leads another; and Northrop Grumman Corporation, working with Virgin Galactic, make up the last. Meanwhile, SpaceX announced yesterday it completed a successful test on its way to making a reusable Falcon 9 rocket.

"There really isn't any kind of vehicle today that does exactly what they're asking people to do."

DARPA calls its version of this project Experimental Spaceplane 1, or XS-1. What the agency wants for XS-1 is unique. The craft should launch 3,000-pound to 5,000-pound unmanned payloads to low-Earth orbit for less than $5 million per flight. The whole launch process needs to be streamlined, too: DARPA wants to see 10 flights in 10 days.

For one thing, humans have never made launch vehicles with reusable rockets. Reusable passenger spaceships, like the vehicles Virgin Galactic is developing, are supposed to reach suborbital altitudes, not low-Earth orbit. NASA's Space Shuttles were reusable, but required days of refurbishing in between flights. Even among the one-time-use satellite launchers available today, none have quite the carrying capacity or price of Experimental Spaceplane 1. For example, Orbital Sciences' Pegasus XL carries just 1,000 pounds and costs an estimated $30 million to $40 million for a low-Earth-orbit flight. SpaceX's (current, non-reusable) Falcon 9 carries about 20,000 pounds, at a cost of $54 million per flight.

Cheaper launches would mean more people could send more stuff to space. DARPA hopes the XS-1, once launched, will serve the students and startups that build small, affordable cubesats, says Alan Wilhite, an aerospace engineering professor at Georgia Tech who previously worked on reusable shuttles at NASA.

"This is a DARPA-hard kind of problem."

In addition, a vehicle that could launch quickly could be helpful for military objectives. "Let's say you're planning a raid to find the next Osama bin Laden, something like that, and due to the timing of it, you don't have a satellite in the right place," Walter-Range says. "You have a small satellite on the ground and you just need to get it up tomorrow."

Right now, you would need to schedule a flight like that years in advance. With the XS-1's more frequent flying schedule, however, "you would just bump the next payload, put your satellite on there, and off you go," Wilhite says.

So why has nobody been able to make an XS-1 before? Different experts cited different reasons. Wilhite, who headed the Vehicle Analysis Branch at NASA Langley in the 1980s, points to technologies, such as hypersonic vehicles, that didn't previously exist. Getting an aircraft that's just rocketed up to the edge of space to come back down again—Gently! No crashes that would render the rocket unusable—is another tough problem.

Mitchell Walker, also an aerospace engineer at Georgia Tech, thinks XS-1's toughest hurdles would happen between its back-to-back flights. Once its reusable first stage reaches the ground, engineers would have make sure it's good to go again within 24 hours. "Anybody can get the engine back," Walker says. "The question is, can you convince yourself that it's okay to put your next multi-million-dollar asset on top of it?"

Extensive between-flights safety testing and refurbishing is why the Space Shuttle wouldn't fulfill DARPA's 10-flights-in-10-days requirement. Testing also added significantly to the Space Shuttle's costs.

Of course, the Space Shuttles carried astronauts, a load more precious than any multi-million-dollar NASA project. XS-1 would not only carry unmanned satellites, its 5,000-pound limit means those satellites would be small and likely not too expensive. No James Webb Space Telescopes here. So XS-1's customers might be satisfied with fewer, shorter safety checks, if that meant cheaper, more frequent flights.

Engineering-wise, there are a lot of variables to balance in the XS-1. "It's a really neat problem because it's got a lot of dynamics. Where are you hauling? What are you hauling?" Walker says. "This is a DARPA-hard kind of problem."








12 delightful resources for word nerds everywhere

Scientific American News - 5 hours 18 min ago
My recent post about specialized dictionaries got me thinking about the fun books and sites I have encountered about words and language. I thought I would share a slightly off-topic post about my...

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What Makes Ice Melt Fastest?

Scientific American News - 5 hours 18 min ago
A chemistry challenge from Science Buddies

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A Bold Critic of the Big Bang’s "Smoking Gun"

Scientific American News - 5 hours 18 min ago
David Spergel explains why a widely publicized gravitational-wave discovery could be wrong, and how it could affect the public’s perception of science

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How to Determine the Scientific Consensus on Global Warming

Scientific American News - 5 hours 38 min ago
An academic feud swirls around how best or even whether to express the scientific consensus around climate change

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"Night's Slow Poison": An Excerpt From Our Sci-Fi Special Issue

Popular Science News - 6 hours 18 min ago

"Night's Slow Poison" by Ann Leckie Illustration by Lisa Kay

This is an excerpt from Popular Science's special issue, Dispatches From The Future. Visit iTunes to download the edition onto your iPad, or return to our list of excerpts.

The Jewel of Athat was mainly a cargo ship, and most spaces were narrow and cramped. Like the Outer Station, where it was docked, it was austere, its decks and bulkheads scuffed and dingy with age. Inarakhat Kels, armed, and properly masked, had already turned away one passenger, and now he stood in the passageway that led from the station to the ship, awaiting the next.

The man approached, striding as though the confined space did not constrain him. He wore a kilt and embroidered blouse. His skin was light brown, his hair dark and straight, cut short. And his eyes . . . Inarakhat Kels felt abashed. He had thought that in his years of dealing with outsiders he had lost his squeamishness at looking strangers in the face.

The man glanced over his shoulder, and cocked an eyebrow. “She was angry.” The corners of his mouth twitched in a suppressed grin.

“One regrets.” Inarakhat Kels frowned behind his mask. “Who?”

“The woman in line before me. I take it you refused to let her board?”

“She carried undeclared communication implants.” Privately, Kels suspected her of being a spy for the Radchaai, but he did not say this. “One is, of course, most sorry for her inconvenience, but . . . ”

“I’m not,” the man interrupted. “She nearly ruined my supper last night insisting that I give up my seat, since she was certain she was of a higher caste than I.”

“Did you?”

“I did not,” said the man. “I am not from Xum, nor are we anywhere near it, so why should I bow to their customs? And then this morning she shoved herself in front of me as we waited outside.” He grinned fully. “I confess myself relieved at not having to spend six months with her as a fellow passenger.”

“Ah,” Kels said, his voice noncommittal. The grin, the angle of the man’s jaw—now he understood why the eyes had affected him. But he had no time for old memories. He consulted his list. “You are Awt Emnys, from the Gerentate.” The man acknowledged this. “Your reason for visiting Ghaon?”

“My grandmother was Ghaonish,” Awt Emnys said, eyes sober that had previously been amused. “I never knew her, and no one can tell me much about her. I hope to learn more in Athat.”

Whoever she was, she had been from the Ghem agnate, Kels was certain. His eyes, his mouth, the line of his chin . . . With just a little more information, Kels could tell Awt which house his grandmother had been born in. “One wishes you good fortune in your search, Honored Awt,” he said, with a small bow he could not suppress.

Awt Emnys smiled in return, and bowed respectfully. “I thank you, Honored,” he said. “I understand I must disable any communications implants.”

“If they are re-activated during the voyage, we will take any steps necessary to preserve the safety of the ship.”

Awt’s glanced at the gun at Kels’ waist. “Of course. But is it really so dangerous?”

“About three months in,” said Kels, in his blandest voice, “we will pass the last ship that attempted to traverse the Crawl with live communications. It will be visible from the passengers’ lounge.”

Awt grinned. “I have an abiding wish to die old, in my bed. Preferably after a long and boring life tracking warehouse inventories.”

Kels allowed himself a small smile. “One wishes you success,” he said, and stepped aside, pressing against the wall so that Awt could pass him. “Your belongings will be delivered to your cabin.”

“I thank you, Honored.” Awt brushed Kels as he passed, awakening some unfamiliar emotion in him.

“Good voyage,” Kels murmured to the other man’s back, but there was no sign Awt had heard.

#

Ghaon is a moonless blue and white jewel orbiting a yellow sun. Its three continents provide every sort of terrain, from the great deserts of southern Lysire, and the rivers and gentle farmlands of the north and west of that same continent, to the mountains of Aneng, still fitfully smoking. Arim, the third continent, is arctic and uninhabited. Aside from the sorts of industry and agriculture that support the population of any world, Ghaon produces pearls and ingeniously carved corals, which, when they find their way outside the Crawl, are highly valued. Flutes carved from the wood of Aneng’s western forests are prized by Gerentate musicians.

According to legend, the first inhabitants of Ghaon came from a world called Walkaway, the location of which is unknown. There were thirteen original settlers, three agnates of four people each plus one eunuch priest of Iraon. The three agnates parceled out the world among themselves: Lysire, Aneng, and the surface of the sea. The priest blessed the division, and each agnate prospered and filled the world.

The legend is only that, of course. It is impossible that thirteen people would possess the genetic diversity required to populate a planet, and in any case studies show that the first human inhabitants of Ghaon, whose descendants now populate Lysire and Aneng, derived largely from the same populations that eventually made up much of the Gerentate. The ancestors of the sea-going agnates arrived several thousand years later, and their origins are obscure.

In any case, the first colonists must have either known about the Crawl before they arrived, or constructed it themselves. The latter seems staggeringly unlikely.

Gerentate explorers found Ghaon some years after that entity’s expansionist phase had run itself out, and so the only threat they presented was a trickle of ill-bred, bare-faced tourists.

But the Radch was another matter. Every soul on Ghaon, from the smallest infant at the breast to the most ancient Lysire matriarch in her tent on the edge of the drylands, believed that the nefarious Anaander Mianaai, overlord of the Radch, had cast a covetous eye on Ghaon and contemplated how he might make it his own.

To keep reading, visit iTunes and download our Dispatches From The Future special issue onto your iPad.








Yellow Light Grows the Best Algae for Biofuels

Scientific American News - 6 hours 18 min ago
Chiplike screening devices show that yellow light gets algae to make more lipids for fuels

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Act on Climate Change, but Tackle Other Global Problems, Too

Scientific American News - 6 hours 48 min ago
Should action on the climate be just another line item in the budget?

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New Brain Implant Conquers Vertigo

Scientific American News - 8 hours 18 min ago
Surgeons have implanted a new prosthesis in four patients to correct disabling dizziness. The device may someday restore balance to hundreds of thousands more

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Humans among the primates

Scientific American News - 8 hours 54 min ago
It is not in the least bit controversial to picture humans* within the context of the placental mammal group that we belong to, the primates.

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Court Sentences Rhino Poacher to a Record 77 Years

Scientific American News - 9 hours 5 min ago
A South African court has sentenced a rhino poacher to 77 years in jail, the heaviest penalty imposed by authorities desperate to halt a wave of poaching that is threatening the population of the...

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Salmonella's Favorite Food Could Be Its Achilles' Heel

Scientific American News - Wed, 07/23/2014 - 19:36
Salmonella's primary fuel source is the molecule fructose-asparagine. Starving it of that fuel in an infected person could kill it without harming beneficial gut bacteria. Karen Hopkin...

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The High-Heel Hottie Effect: The Evolutionary Psychology of Women’s Shoes

Scientific American News - Wed, 07/23/2014 - 17:44
On a trip to Italy a few years ago, my partner and I peered into the faraway distance at that famously angled phallus that is the Leaning Tower of Pisa, when suddenly we became aware of a small scene...

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Dogs Experience Jealousy

Scientific American News - Wed, 07/23/2014 - 16:00
Jealousy appears to be a primordial emotion seen not only in humans, but in other animals as well

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Introducing Our First Sci-Fi Special Issue For The iPad

Popular Science News - Wed, 07/23/2014 - 12:30

Dispatches from the Future Download a copy from iTunes. Popular Science

We love science fiction here at Popular Science. Many of the real-life innovations and advances that fill our pages every month, in fact, started as pie-in-the-sky ideas born by people thinking creatively about a better future. These visions only get more vivid, the stories more stimulating and innovative, as we craft each new issue.

So today we present something extra-special, called Dispatches From The Future: an entire digital issue packed with more than 100 pages of awesome science fiction and designed for the iPad. You can download a copy from iTunes here.

Our crown jewel in this edition is the first-ever graphic novel adaptation of the Isaac Asimov classic Nightfall, complete with animations. Also included are amazing short stories by award-winning sci-fi authors Will McIntosh, Ann Leckie, and Seanan McGuire. Finally, we've folded in collections of original science fiction we produced in 2013 and 2014, which feature some of the brightest minds in the field musing how we will live—on Earth and beyond—in the decades and centuries to come.

We're publishing excerpts of Dispatches From The Future here, one per day, to give you a taste of the issue. (Each cover image will stay grayed-out until that excerpt is posted.) So keep checking back throughout the week—if you can wait that long!

"The Defenders" by Will McIntosh

"The Defenders" by Will McIntosh Illustration by Lisa Kay

Twenty-eight years ago, humanity was almost wiped out by invaders called Luyten. But human-created artificial intelligence saved humans in the nick of time. Now, after decades of self-imposed exile in Australia, the A.I. defenders are allowing a few humans to visit. The human ambassadors have no idea what is in store. [Click to read an excerpt]

"Night's Slow Poison" by Ann Leckie

"Night's Slow Poison" by Ann Leckie Illustration by Lisa Kay

Many worlds away, Inarakhat Kels paces the halls and corridors aboard an interstellar cargo ship on a six-month journey between planets. He and the other members of his security watch keep on the lookout for treacherous spies, harmful technology, and anything else that might put the ship and its inhabitants at risk of destruction. On this particular trip, a meeting with a peculiar traveller forces him to confront the memories of the home-planet he abandoned long ago, and of a lost-love he was forced to leave behind. [Click to read an excerpt]

"The Tolling of Pavlov's Bells" by Seanan McGuire

"The Tolling of Pavlov's Bells" by Seanan McGuire Illustration by Lisa Kay

Dr. Diana Weston is a virologist and a bestselling author, with a penchant for writing medical thrillers about catastrophic disease outbreaks. But underneath her attractive smile and sharp wit lies a troubled psyche. When the fictional plots she pens start showing up in the real world, the dark side to her life begins to come out of the shadows. [Excerpt coming soon]

"Nightfall" by Isaac Asimov

"Nightfall" by Isaac Asimov Illustration by Ryan Inzana

The scientists of Saro University have predicted civilization's impending doom, caused by the extinguishing of the planet's last light-giving star in just four hours. But some are skeptical that the Darkness will have the effect that the scientists anticipate, so a young journalist has come to seek the truth. His shocking discovery is a story for the ages. [Excerpt coming soon]

Download our entire Dispatches From The Future special issue for the iPad from iTunes.








Hit by Climate Change, Dwindling Antarctic Seal Population Grows More Diverse

Scientific American News - Wed, 07/23/2014 - 12:12
As sea waters in the South Atlantic warm, the amount of krill available for seals drops, leading to a smaller yet more genetically varied population

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