False memories prime immune system for future attacks

IN A police line-up, a falsely remembered face is a big problem. But for the body's police force – the immune system – false memories could be a crucial weapon.

When a new bacterium or virus invades the body, the immune system mounts an attack by sending in white blood cells called T-cells that are tailored to the molecular structure of that invader. Defeating the infection can take several weeks. However, once victorious, some T-cells stick around, turning into memory cells that remember the invader, reducing the time taken to kill it the next time it turns up.

Conventional thinking has it that memory cells for a particular microbe only form in response to an infection. "The dogma is that you need to be exposed," says Mark Davis of Stanford University in California, but now he and his colleagues have shown that this is not always the case.

The team took 26 samples from the Stanford Blood Center. All 26 people had been screened for diseases and had never been infected with HIV, herpes simplex virus or cytomegalovirus. Despite this, Davis's team found that all the samples contained T-cells tailored to these viruses, and an average of 50 per cent of these cells were memory cells.

The idea that T-cells don't need to be exposed to the pathogen "is paradigm shifting," says Philip Ashton-Rickardt of Imperial College London, who was not involved in the study. "Not only do they have capacity to remember, they seem to have seen a virus when they haven't."

So how are these false memories created? To a T-cell, each virus is "just a collection of peptides", says Davis. And so different microbes could have structures that are similar enough to confuse the T-cells.

To test this idea, the researchers vaccinated two people with an H1N1 strain of influenza and found that this also stimulated the T-cells to react to two bacteria with a similar peptide structure. Exposing the samples from the blood bank to peptide sequences from certain gut and soil bacteria and a species of ocean algae resulted in an immune response to HIV (Immunology, doi.org/kgg).

The finding could explain why vaccinating children against measles seems to improve mortality rates from other diseases. It also raises the possibility of creating a database of cross-reactive microbes to find new vaccination strategies. "We need to start exploring case by case," says Davis.

"You could find innocuous pathogens that are good at vaccinating against nasty ones," says Ashton-Rickardt. The idea of cross-reactivity is as old as immunology, he says. But he is excited about the potential for finding unexpected correlations. "Who could have predicted that HIV was related to an ocean algae?" he says. "No one's going to make that up!"

This article appeared in print under the headline "False memories prime our defences"

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Anti-North Korea leaflets launched on Kim's birthday

IMJINGAK, South Korea: North Korean defectors in the South launched 200,000 anti-Pyongyang leaflets across the tense inter-Korean border on Saturday, the birth anniversary of the North's late leader Kim Jong-Il.

The defectors used gas-filled balloons to float the leaflets along with $1 currency notes across the western border town of Imjingak, despite high tensions owing to the North's third nuclear test on Tuesday.

The balloons were inscribed with slogans such as "Stop provocative acts with missiles and nuclear tests", "North Koreans rise up" and "The Kim dynasty will soon collapse".

North Korea celebrates the birthdays of both late leaders -- Kim Jong-Il's on February 16 and his father Kim Il-Sung's on April 15 -- as major national holidays.

Kim Jong-Il, who died of heart attack in December 2011, was succeeded by his son Jong-Un.

Anti-Pyongyang activists momentarily suspended such leaflet launches until after the South's presidential election in December as the government urged them to halt such activities for fear of provoking Pyongyang.

North Korea has in the past threatened "merciless military strike" in response to anti-regime propaganda leaflets, with local residents warned to evacuate such areas.

The North conducted a third nuclear test on Tuesday, whose detonation power was much larger than those of two previous ones in 2006 and 2009.

Pyongyang said the test was a riposte to UN sanctions imposed after its launch of a long-range rocket in December, which it claimed was part of a legitimate space programme.

- AFP/ck

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E-orders for 128GB Surface Pro to ship in 2-3 weeks -- Microsoft

Microsoft provided another update at the end of this week regarding the availability of its sold-out 128GB version of the Surface Pro.

A February 15 Surface Blog post said that those ordering through the Microsoft online store in the U.S. can place an order for the 128GB model and have it ship in two to three weeks.

The new post also provided updated information for those wanting to "reserve" the Intel-based PC/tablet hybrid
Surface Pro devices. Up until now, Microsoft officials have declined comment when asked whether users would be able to pre-order Surface Pros.

Here's the latest Surface Pro availability guidance:

At Best Buy (U.S.): Inventory levels are increasing and many Best Buy stores have Surface Pro units for sale in-store. If the store does not have stock, you can reserve a Surface Pro (64GB and 128GB). Please note that Best Buy is only taking reservations in their stores for Surface Pro based on new inventory they know is coming in next week, so it's possible that reservations could become "sold out."

At Staples (U.S.): Many Staples stores have Surface Pro units for sale in stores. If the store does not have stock, you can place a kiosk order in store to purchase Surface Pro 64GB for delivery.

For Canada: In Best Buy and Future Shop stores you can reserve the 64GB Surface Pro in stores at this time. Staples has availability online while inventory lasts and more inventory has been ordered to ensure store availability in the near future. More details to come on the 128GB Surface Pro availability in Canada.

It seems that Staples is making the 128GB Surface Pros available for order online and that they are not being stocked in Staples brick-and-mortar outlets, as I noted earlier this week.

Microsoft is "work(ing) around the clock to meet that demand with production and get new inventory into retail," the post concluded. Company officials advise customers interested in the Pros to call ahead before venturing to stores this weekend, in spite of guidance earlier in the week that more stores would have stock on hand starting on Saturday, February 16.

It's still unclear why there are not enough Surface Pros on the market. Is it that Microsoft seriously underestimated demand for 128GB Surface Pros -- a happy problem for the Softies? Or have supply-chain problems led to device shortages (a not-so-happy problem)? Microsoft's Surface Pro devices went on sale February 9.

This story originally appeared on ZDNet under the headline "Microsoft: Online orders for 128 GB Surface Pro to ship in two to three weeks."

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Why the Dog Show Winner Looks Like a Monkey

Standing less than a foot tall and easily cradled in one of trainer Ernesto Lara's arms, Banana Joe made big news for a small dog when he became the first affenpinscher to win the Westminster Kennel Club dog show on Tuesday.

His short stature and flattened face might not make Banana Joe look like a typical winner: The name "affenpinscher" is German for "monkey terrier," and its mug is definitely simian in appearance. Now this lesser known breed is basking in the spotlight, monkey face and all. (Read "How to Build a Dog" in National Geographic magazine.)

Why the Flat Face?

People like dogs whose faces kind of look like people, with a squished-in nose and forward-facing eyes: Pekinese, bullmastiffs, and affenpinschers, to name a few. "It's mimicking the way humans appear," said Jeffrey Schoenebeck, a research fellow at the National Institutes of Health who has analyzed the development of shortened canine snouts. Several centuries ago, breeders probably sought out parents with a flat face. (Genetics note: Gene BMP3 likely contributes to a flat face in toy breeds.)

And so Banana Joe's mug reflects centuries of genetic manipulation. There's no advantage for the dog, Schoenebeck notes, except that humans would crave it more as a companion. (Related: Gallery of Dog Pictures.)

What About That Tongue?

Banana Joe sticks out his little pink tongue a lot. Maybe more than your run-of-the-mill canine. The reason may be the flat face. "There's probably less room in their mouth" for the tongue, said Schoenebeck. "It's hanging out."

Why so Small?

"The Affenpinscher comes from a terrier background," explained NIH senior staff scientist Heidi Parker, and like all terriers, it was bred to chase. The early affenpinschers' specialty was hunting down rats and other vermin for its owners. Breeding for a small size came later, as ladies started bringing affenpinschers into the home as lap dogs-and to keep away vermin that might otherwise hide in corners or under long skirts. Today's affenpinschers are in the 6-to-13 pound (3-to-6 kilogram) range.

But the dog's size hasn't given it an inferiority complex. "Most of these little guys do not realize they're as small as they are," Parker says. Toy dogs have been known to chase birds and other animals that rival them in size.

What Comes After Westminster?

Dog lovers may crave an affenpinscher. And that could cause problems if breeders try to produce more pups.

"You'll see some breeds go through sudden explosions, where they'll go from small numbers to really large numbers," says Parker. "Usually that means an increase in genetic diseases." There aren't a lot of potential parents for a purebred litter, so the odds of inbreeding, and its related diseases, go up.

And What About Banana Joe?

Now that he's made us aware of his breed, Banana Joe will retire from competition and live with his Dutch owner, free to fulfill his heritage as a lap dog.

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Carnival Cruise Ship Hit With First Lawsuit

The first lawsuit against Carnival Cruise Lines has been filed and it is expected to be the beginning of a wave of lawsuits against the ship's owners.

Cassie Terry, 25, of Brazoria County, Texas, filed a lawsuit today in Miami federal court, calling the disabled Triumph cruise ship "a floating hell."

"Plaintiff was forced to endure unbearable and horrendous odors on the filthy and disabled vessel, and wade through human feces in order to reach food lines where the wait was counted in hours, only to receive rations of spoiled food," according to the lawsuit, obtained by ABCNews.com. "Plaintiff was forced to subsist for days in a floating toilet, a floating Petri dish, a floating hell."

Click Here for Photos of the Stranded Ship at Sea

The filing also said that during the "horrifying and excruciating tow back to the United States," the ship tilted several times "causing human waste to spill out of non-functioning toilets, flood across the vessel's floors and halls, and drip down the vessel's walls."

Terry's attorney Brent Allison told ABCNews.com that Terry knew she wanted to sue before she even got off the boat. When she was able to reach her husband, she told her husband and he contacted the attorneys.

Allison said Terry is thankful to be home with her husband, but is not feeling well and is going to a doctor.

Carnival's Triumph Passengers: 'We Were Homeless' Watch Video

Girl Disembarks Cruise Ship, Kisses the Ground Watch Video

Carnival Cruise Ship Passengers Line Up for Food Watch Video

"She's nauseated and actually has a fever," Allison said.

Terry is suing for breach of maritime contract, negligence, negligent misrepresentation and fraud as a result of the "unseaworthy, unsafe, unsanitary, and generally despicable conditions" on the crippled cruise ship.

"Plaintiff feared for her life and safety, under constant threat of contracting serious illness by the raw sewage filling the vessel, and suffering actual or some bodily injury," the lawsuit says.

Despite having their feet back on solid ground and making their way home, many passengers from the cruise ship are still fuming over their five days of squalor on the stricken ship and the cruise ship company is likely to be hit with a wave of lawsuits.

"I think people are going to file suits and rightly so," maritime trial attorney John Hickey told ABCNews.com. "I think, frankly, that the conduct of Carnival has been outrageous from the get-go."

Hickey, a Miami-based attorney, said his firm has already received "quite a few" inquiries from passengers who just got off the ship early this morning.

"What you have here is a) negligence on the part of Carnival and b) you have them, the passengers, being exposed to the risk of actual physical injury," Hickey said.

The attorney said that whether passengers can recover monetary compensation will depend on maritime law and the 15-pages of legal "gobbledygook," as Hickey described it, that passengers signed before boarding, but "nobody really agrees to."

One of the ticket conditions is that class action lawsuits are not allowed, but Hickey said there is a possibility that could be voided when all the conditions of the situation are taken into account.

One of the passengers already thinking about legal action is Tammy Hilley, a mother of two, who was on a girl's getaway with her two friends when a fire in the ship's engine room disabled the vessel's propulsion system and knocked out most of its power.

"I think that's a direction that our families will talk about, consider and see what's right for us," Hilley told "Good Morning America" when asked if she would be seeking legal action.

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Sand-grain-sized drum extends reach of quantum theory

The banging of a tiny drum heralds the intrusion of the weird world of quantum mechanics into our everyday experience. Though no bigger than a grain of sand, the drum is the largest object ever to have been caught obeying the uncertainty principle, a central idea in quantum theory.

As well as extending the observed reach of quantum theory, the finding could complicate the hunt for elusive gravitational waves : it suggests that the infinitesimal motion caused by these still-hypothetical ripples in spacetime could be overwhelmed by quantum effects.

The uncertainty principle says that you cannot simultaneously determine both a particle's exact position and momentum. For example, bouncing a photon off an electron will tell you where it is, but it will also change the electron's motion, creating fresh uncertainty in its speed.

This idea limits our ability to measure the properties of very small objects, such as electrons and atoms. The principle should also apply to everyday, macroscopic objects, but this has not been tested – for larger objects, the principle's effects tend to be swamped by other uncertainties in measurement, due to random noise, say.

Quantum drum

To extend the known reach of the uncertainty principle, Tom Purdy and colleagues of the University of Colorado, Boulder, created a drum by tightly stretching a 40-nanometre-thick sheet of silicon nitride over a square frame with sides of half a millimetre – about the width of a grain of sand. They placed the drum inside a vacuum chamber cooled to a few degrees above absolute zero, minimising any interference by random noise.

By continuously firing a stream of photons at the drum they were able to get increasingly precise measurements of the position of the skin at any moment. However, this also caused the skin to vibrate at an unknown speed. When they attempted to determine its momentum, the error in their measurement had increased – just as the uncertainty principle predicts.

"You don't usually have to think about quantum mechanics for objects you can hold in your hand," says Purdy.

That the uncertainty principle holds sway at such a large scale could affect the hunt for gravitational waves, which are predicted by Einstein's theory of general relativity but have never been detected.

Mitigation strategy

Gravitational wave detectors look for very slight changes in the distance between two test masses caused by passing spacetime ripples. Purdy says his team's experiment confirms long-held suspicions that quantum uncertainty could overwhelm these very small changes.

Now he and others can use the drum to explore more advanced measurement techniques to mitigate the effects. For example, uncertainty in an object's momentum could lead to future uncertainty in its position and there should be ways to minimise such knock-on effects. "You can't avoid the uncertainty principle, but you can in some clever ways make it [such that] increasing the momentum doesn't add back to the uncertainty in position at a later time," says Purdy.

His experiment is a neat demonstration of the breakdown of the traditional notion that the atomic world is quantum while the macroscopic world is classic, says Gerard Milburn of the University of Queensland in Brisbane, Australia, who was not involved in the work. Previous, attempts to blur the quantum-classical divide have involved entangling diamonds and demonstrating quantum superposition in a strip of metal.

Despite these feats, Milburn doesn't rule out the prospect of a breakdown on really large scales. "Of course maybe one day we will see quantum mechanics fail at some scale. Testing it to destruction is a good motivation for going down this path," he says.

Journal reference: Science, DOI: 10.1126/science.1231282

If you would like to reuse any content from New Scientist, either in print or online, please contact the syndication department first for permission. New Scientist does not own rights to photos, but there are a variety of licensing options available for use of articles and graphics we own the copyright to.

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S. Korea leader says only regime fall will change North

SEOUL: North Korea can never be made to abandon its nuclear weapons programme, South Korean President Lee Myung-Bak said Friday, arguing that only regime collapse could remove the threat from Pyongyang.

As the UN Security Council continues to debate how to punish the North for its latest nuclear test, the outgoing president suggested the best way forward was to try to foment unrest among the North Korean people.

"It has become impossible to have North Korea give up its nuclear weapons through dialogue and negotiations", Lee told a meeting of senior dignitaries including former government ministers and religious leaders.

"We cannot hope the North will part with its nuclear programmes until its regime changes or collapses", he said.

"We can help change the North Korean people, if not the North Korean regime itself."

Lee is set to leave office in 10 days at the end of a five-year term marked by an almost complete breakdown in contacts between Seoul and Pyongyang.

Lee had always promised to take a harder line than his predecessors, making continued aid to the impoverished North conditional on progress in talks on its nuclear programme.

His successor, president-elect Park Geun-Hye, campaigned on a policy of greater engagement with Pyongyang, but Tuesday's nuclear test will almost certainly see that policy shelved for months, if not longer.

-AFP/fl

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Photoshop 1.0 source code now a museum artifact

The Photoshop 1.0 splash screen

(Credit:
Computer History Museum)

The Computer History Museum has made the source code for Photoshop 1.0.1 into an exhibit that lets the public, or at least programmers, appreciate the inner workings of the historic software.

The museum published the software yesterday, following up on its earlier release of the source code underlying Apple's original MacPaint.

Source code is what humans write -- in Photoshop 1.0's case the brothers Thomas and John Knoll. The initial Photoshop is written in written 128,000 lines of code, a combination of the high-level Pascal programming language and low-level assembly-language instructions. When converted to machine code, the program was small enough to fit on a floppy disk.

Photoshop started in the 1980s as a personal project the brothers called Display, but they started trying to commercialize it, according to the museum's exhibit. Their first success was version 0.87, which scanner maker Barneyscan called Barneyscan XP, but Adobe Systems agreed to a deal in 1989 and distributed Photohshop 1.0.1 in 1990.

Photoshop 1.0.1 dates from a time when many computer screens were small and could display only black or white pixels -- not even gray. And of course image processing is very taxing for computer chips. Although today's large, color monitors are very different, Photoshop still pushes computer processors about as hard as they'll go.

The museum also published the Photoshop 1.0 user guide and tutorial documentation.

Of course, new types of museum exhibits mean things change for those perusing the exhibits, too. In this case, it's a 1,400-word license agreement to see the Photoshop source.

Photoshop 1.0 in action

(Credit:
Creative Bits and the Computer History Museum)

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Why We Walk … and Run … And Walk Again to Get Where We're Going

You have to get to a bus stop to catch the once-an-hour express ... or to a restaurant to meet a friend ... or to a doctor's office. You've got maybe a half a mile to cover and you're worried you'll be late. You run, then you stop and walk, then run some more.

But wait. Wouldn't it be better to run the whole way?

Not necessarily.

A new study by an assistant professor of mechanical engineering at Ohio State University tests the theory that people subconsciously mix walking and running so they get where they need to. The idea is that "people move in a manner that minimizes energy consumption," said the professor, Manoj Srinivasan.

Srinivasan asked 36 subjects to cover 400 feet (122 meters), a bit more than the length of a football field. He gave them a time to arrive at the finish line and a stopwatch. If the deadline was supertight, they ran. If they had two minutes, they walked. And if the deadline was neither too short nor too far off, they toggled between walking and running.

The takeaway: Humans successfully make the walk-run adjustment as they go along, based on their sense of how far they have to go. "It's not like they decide beforehand," Srinivasan said. (Get tips, gear recommendations, and more in our Running Guide.)

The Best Technique for "the Twilight Zone"

"The mixture of walking and running is good when you have an intermediate amount of time," he explained. "I like to call it 'the Twilight Zone,' where you have neither infinite time nor do you have to be there now."

That ability to shift modes served ancient humans well. "It's basically an evolutionary argument," Srinivasan said. A prehistoric human seeking food would want to move in a way that conserves some energy so that if food is hard to find, the hunter won't run out of gas—and will still be able to rev it up to escape predators.

The study, published on January 30 in the Journal of the Royal Society Interface, doesn't answer that question of how we make such adjustments.

Runners: Take a Break if You Need It

The mix of walking and running is also something that nonelite marathoners are familiar with. Covering 26.2 miles might take less of a toll if the runner stops running from time to time, walks a bit, then resumes a jogging pace. "You use less energy overall and also give yourself a bit of a break," Srinivasan noted. (Watch: An elite marathoner on her passion for running.)

One take-home lesson is: Runners, don't push it all the time. A walk-run mix will minimize the energy you expend.

Lesson two: If you're a parent walking with your kid, and the kid lags behind, then runs to catch up, then lags again, the child isn't necessarily trying to annoy you. Rather, the child is perhaps exhibiting an innate ability to do the walk-run transition.

Potential lesson three: The knowledge that humans naturally move in a manner that minimizes energy consumption might be helpful in designing artificial limbs that feel more natural and will help the user reduce energy consumption.

The big question for Manoj Srinivasan: Now that he has his walk-run theory, does he consciously switch between running and walking when he's trying to get somewhere? "I must admit, no," he said. "When I want to get somewhere, I just let the body do its thing." But if he's in a rush, he'll make a mad dash.

"Talk to you tomorrow," he signed off in an email to National Geographic News. "Running to get to teaching now!"

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Nightmare Ends: Passengers Leave Disabled Ship

After five days without power in the Gulf of Mexico, the Carnival Triumph cruise ship carrying more than 4,000 people arrived in Mobile, Ala., to greet a cheering crowd of friends and family members waiting to embrace their loved ones.

Passengers began to disembark the damaged ship around 10:15 p.m. CT Thursday and continued into the overnight hours. Other waiting passengers lined the decks of the ship, waving, and whistling to those on shore. "Happy V-Day" read a homemade sign made for the Valentine's Day arrival and another, more starkly: "The ship's afloat, so is the sewage."

Some still aboard chanted, "Let me off, let me off!" and "Sweet Home Alabama."

The Carnival Triumph departed Galveston, Texas, last Thursday and lost power Sunday after a fire in the engine room disabled the vessel's propulsion system and knocked out most of its power.

After power went out, passengers texted ABC News that sewage was seeping down the walls from burst plumbing pipes, carpets were wet with urine, and food was in short supply. Reports surfaced of elderly passengers running out of critical heart medicine and others on board squabbling over scarce food.

Click Here for Photos of the Stranded Ship at Sea

Passengers said many of the cabins became intolerable with the smell of raw sewage. They were forced to create makeshift beds out of lounge chairs on the ship's deck.

AP Photo/John David Mercer

Girl Disembarks Cruise Ship, Kisses the Ground Watch Video

Carnival CEO Gerry Cahill: 'I Want to Apologize' Watch Video

Carnival Cruise Ship Passengers Line Up for Food Watch Video

"We kind of camped out by our lifeboat. We would have nightmares about Titanic basically happening," passenger Kendall Jenkins told ABC News Radio after disembarking from the ship.

"I am just so blessed to be back home," she added.

Jenkins was one of many passengers that were photographed kissing the ground when they exited the ship.

WATCH: Carnival CEO Gerry Cahill Apologizes to Passengers

Approximately 100 buses were waiting to take passengers on the next stage of their journey. Passengers have the option to take a bus ride to New Orleans or Galveston, Texas, where the ill-fated ship's voyage began. From there, passengers will take flights home, which Carnival said they would pay for.

Inside the buses, Carnival handed out bags of food that included French fries, chicken nuggets, honey mustard barbecue sauce and apples.

Deborah Knight, 56, decided to stay in Mobile after the arduous journey was over rather than board a bus for a long ride. Her husband Seth drove in from Houston and they checked in at a downtown Mobile hotel.

"I want a hot shower and a daggum Whataburger," said Knight.

She said she was afraid to eat the food on board and had gotten sick while on the ship.

Cruise Ship Newlyweds Won't Be Spending Honeymoon on a Boat

For 24-year-old Brittany Ferguson of Texas, not knowing how long passengers had to endure their time aboard was the worst part.

"I'm feeling awesome just to see land and buildings," Ferguson said, who was in a white robe given to her aboard. "The scariest part was just not knowing when we'd get back," she told The Associated Press.

Carnival president and CEO Gerry Cahill praised the ship's crew and told reporters that he was headed on board to apologize directly to its passengers shortly before the Carnival Triumph arrived in Mobile.

"I know the conditions on board were very poor," Cahill said Thursday night. "I know it was very difficult, and I want to apologize again for subjecting our guests for that. ... Clearly, we failed in this particular case."

Luckily no one was hurt in the fire they triggered the power outage, but many passengers aboard the 900 foot colossus said they smelled smoke and were living in fear.

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