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"

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.

All comments should respect the New Scientist House Rules. If you think a particular comment breaks these rules then please use the "Report" link in that comment to report it to us.

If you are having a technical problem posting a comment, please contact technical support.

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Tennis: Nadal struggles into Brazil Open final

SAO PAULO: Rafael Nadal struggled into the Brazil Open final on Saturday by downing Argentine lucky loser Martin Alund in three sets.

The former world number one, who is recovering from a knee injury, battled hard to dismiss his 27-year-old opponent, who is ranked 111 in the world, winning 6-3, 6-7 (2/7), 6-1 in nearly two hours.

Sunday's final will pit the 26-year-old Spanish star against Argentine David Nalbandian, who whipped Italian Simone Bolelli 6-3, 7-5 in 85 minutes in the other semi-final.

Nadal is the top seed in this $455,775 tournament, his second comeback event after a seven-month absence due to his knee injury and then illness.

Last week, he competed in the Vina del Mar Open in Chile, losing the singles and doubles finals.

Alund more than held his own against the world number five, prevailing in the second set before Nadal stepped on the gas and sealed victory with a masterful performance in the decisive third set.

The Spaniard, who has 11 Grand Slam titles, won the Brazil Open in 2005, when it was held in Costa do Sauipe in eastern Bahia state.

Last year, the tournament was moved to Sao Paulo.

The Brazil Open is part of the Latin American clay court swing, along with the Vina del Mar event and the Mexico Open, in Acapulco, where Nadal plans to compete later this month.

The three low-profile Latin American events are routinely ignored by the world's top three players -- Novak Djokovic, Roger Federer and Andy Murray.

- AFP/fa

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Russian meteorite: The conspiracy theories

A strange time for a military attack?

(Credit:
CNN; screenshot by Chris Matyszczyk/CNET)

A good hearty conspiracy theory can shine a sharp light on two of humanity's most enduring traits.

One, of course, is humanity's boundless imagination. The other is humanity's essential suspicion of humanity.

So while you might be deeply immersed in Bill Nye's explanation of the Russian meteorite, those with darker sensibilities have filled the Web with their fears and hauntings about the phenomenon.

There are few nations with greater awareness of dark sensibilities than Russia. The fact that there seems to be little evidence of meteorite fragments on the ground has encouraged some Russians to offer their own suspicions.

As the Toronto Globe and Mail reports, nationalist leader Vladimir Zhirinovsky hasn't been slow to offer something of a Hot War perspective.

"It's not meteors falling. It's a new weapon being tested by the Americans," he was quoted as saying.

We know from our recent experience of North Korea that weapons testing is an imprecise science.

But if you were an American in the mood to test a weapon, would Chelyabinsk, Russia, be your very first choice of place for the experiment?

Perhaps Tallahassee; Area 51; and Bialystok, Poland, were all unavailable due to prior commitments. Or perhaps it wasn't the Americans, but, say, the North Koreans, who mistook Chelyabinsk for, say, Chelsea.

Zhirinovsky's rather emotionally manipulative offering was countered by Russia's Emergency Ministry, which dedicated itself to an extensive rebuttal of his belief (and that of others) that this was some sort of military thing. The rebuttal? "Rubbish."

But that wasn't going to put off the local media, was it? Not only do they have papers to sell, they also have theories to expound to a troubled nation and world.

So, as The Atlantic reports, the local Znak newspaper accepted that this was a meteorite but insisted the explosion was caused by military defense blowing it up.

More Technically Incorrect

Yes, of course it has a source in the military. You thought it didn't?

Though I've watched a few movies in which exciting things happen, I don't find it easy to imagine that some sort of terrestrially created missile-laden aircraft could really explode a meteorite in such a manner.

It is easier to imagine, though, that politicians like Zhirinovsky might take the opportunity to foment a little rage.

Indeed, Alex Jones' infamously well-guarded Infowars site offered that Zhirinovsky insisted that America -- in the person of Secretary of State John Kerry -- had tried to give Russia advance notice of its "attack."

The Drudge Report led me to a piece at Foreign Policy that explained that Sergey Lavrov, Russia's foreign minister, simply hadn't called Kerry back.

Which all suggests that Russia isn't, after all, living in fear of an attack from the U.S. Especially one over Chelyabinsk.

On balance, I prefer to currently believe Nye. He is the science guy, after all. And science guys know scientific events when they see them.

I hope.

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Picture Archive: Making Mount Rushmore, 1935-1941

Photograph from Rapid City Chamber of Commerce/National Geographic

There's no such thing as Presidents' Day.

According to United States federal government code, the holiday is named Washington's Birthday, and has been since it went nationwide in 1885.

But common practice is more inclusive. The holiday expanded to add in other U.S. presidents in the 1960s, and the moniker Presidents' Day became popular in the 1980s and stuck. It may be that George Washington (b. February 22, 1732) andAbraham Lincoln (b. February 12, 1809) still get the lion's share of attention—and appear in all the retail sale ads—on the third Monday in February, but the popular idea is that all 44 presidents get feted.

Mount Rushmore is a lot like that one day a year writ large—and in granite. It's carved 60 feet (18 meters) tall and 185 feet (56 meters) wide, from Washington's right ear to Lincoln's left.

The monument's sculptor, Gutzon Borglum, grew up in Idaho, a first-generation American born to Danish parents. He studied art in France and became good friends with Auguste Rodin. Borglum mostly worked in bronze, but in the early 1910s he was hired to carve the likenesses of Confederate leaders into Stone Mountain in Georgia.

He was about to be fired from that job for creative differences about the same time that a South Dakota historian named Doane Robinson had an idea. Robinson wanted to have a monument carved into the Black Hills of South Dakota, maybe Western historical figures like Chief Red Cloud and Lewis and Clark, each on their own granite spire. (Plan a road trip in the Black Hills.)

Robinson hired Borglum and gave him carte blanche. Borglum was looking for something with national appeal, so he chose to depict four presidents: George Washington, Thomas Jefferson, Theodore Roosevelt, and Abraham Lincoln.

Borglum wanted to represent the first 150 years of the nation's history, choosing four presidents as symbols of their respective time periods. He took a tour of western South Dakota, searching for an ideal canvas.

The sculptor was looking for three things: a surface strong enough to sculpt, a mountain big enough to hold several figures, and a mountain face that received morning sunlight. Mount Rushmore fit the bill and was already part of a national forest, so it was easy to set aside as a national memorial.

Work started in 1927. Calvin Coolidge attended the dedication ceremony. It took 14 years to finish the carving, conducted mostly in summertime because of the area's harsh winters.

There were approximately 30 workers on the mountain at any give time. In total about 400 had worked on it by the time the monument was finished. Though the project involved thousands of pounds of dynamite and perilous climbs, not a single person died during the work.

Borglum himself died of natural causes in 1941, though, just six months before the project was declared "closed as is" by Congress that Halloween. His son Lincoln—named for his father's favorite president—took over.

In the photo above, a worker refines the details of Washington's left nostril.

About 90 percent of the mountain was carved using dynamite, which could get within 3 to 5 inches (8 to 13 centimeters) of the final facial features. For those last few inches, workers used what was known as the honeycomb method: Jackhammer workers pounded a series of three-inch-deep holes followed up by chiselers who knocked off the honeycomb pieces to get the final shape. Then carvers smoothed the "skin's" surface.

—Johnna Rizzo

February 16, 2013

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Meteor Blast 'Something We Only Saw in Movies'

A day after a massive meteor exploded over this city in central Russia, a monumental cleanup effort is under way.

Authorities have deployed around 24,000 troops and emergencies responders to help in the effort.

Officials say more than a million square feet of windows -- the size of about 20 football fields -- were shattered by the shockwave from the meteor's blast. Around 4,000 buildings in the area were damaged.

The injury toll climbed steadily on Friday. Authorities said today it now stands at more than 1,200. Most of those injuries were from broken glass, and only a few hundred required hospitalization.

According to NASA, this was the biggest meteor to hit Earth in more than a century. Preliminary figures suggest it was 50 feet wide and weighed more than the Eiffel Tower.

SEE PHOTOS: Meteorite Crashes in Russia

NASA scientists have also estimated the force of the blast that occurred when the meteor fractured upon entering Earth's atmosphere was approximately 470 kilotons -- the equivalent of about 30 Hiroshima bombs.

Residents said today they still can't believe it happened here.

"It was something we only saw in the movies," one university student said. "We never thought we would see it ourselves."

Throughout the city, the streets are littered with broken glass. Local officials have announced an ambitious pledge to replace all the broken windows within a week. In the early morning hours, however, workers could still be heard drilling new windows into place.

Authorities have sent divers into a frozen lake outside the city, where a large chunk of the meteor is believed to have landed, creating a large hole in the ice. By the end of the day they had not found anything.

They are not the only ones looking for it.

Meteor hunters from around the world are salivating at what some are calling the opportunity of a lifetime. A small piece of the meteor could fetch thousands of dollars and larger chunks could bring in even hundreds of thousands.

Read More..

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"

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.

All comments should respect the New Scientist House Rules. If you think a particular comment breaks these rules then please use the "Report" link in that comment to report it to us.

If you are having a technical problem posting a comment, please contact technical support.

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Mexico to slaughter 486,000 chickens over bird flu

CELAYA, Mexico: Mexico will slaughter 486,000 chickens after an outbreak of bird flu was detected in the central state of Guanajuato, officials said Friday.

Poultry producer Bachoco reported a possible case of H7N3 influenza in five breeder farms late Wednesday, which agriculture ministry officials confirmed on Friday.

Authorities launched preventive measures, testing nearby farms to check if the outbreak had spread elsewhere.

Last year, a bird flu outbreak in the western state of Jalisco forced farmers to slaughter 22 million hens, sparking an egg crisis in Mexico, the world's top consumer of eggs per capita.

- AFP/fa

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Microsoft Surface Pro hoarders try to make a quick buck

Surface Pro at a Microsoft Specialty Store in Glendale, Calif. As of this afternoon, the 128GB model is still out of stock at Los Angeles Microsoft stores.

(Credit:
Brooke Crothers)

The 128GB Surface Pro is a rare commodity at the moment. And stiff eBay asking prices reflect this.

In fact, it wouldn't be a stretch to say that some eBay vendors are hoarding the device, trying to cash in on the scarcity.

Though pretty common with hard-to-get Apple products, it's unusual to see this with a Windows product -- and it's Microsoft's first PC, to boot.

One seller, with a stack of at least 10 Pros, is asking $1,300 for the 128GB model. Other sellers are asking $1,399 and even $1,499. The regular price is $999 for the 128GB model.

So, why is there a shortage to begin with? Though conspiracy theories abound about a staged shortage by Microsoft, others (mostly analysts) believe that suppliers simply weren't ready to deliver enough product to meet demand.

The 128GB model has been virtually unobtainable this week at the Microsoft Store, Best Buy, and Staples. And the status has not changed as of this afternoon based on checks at national retailers.

The Pro is one of the first
Windows 8 tablets to run legacy Windows software and sport a relatively powerful Intel Ivy Bridge processor.

Microsoft Specialty Store on Glendale, Calif.

(Credit:
Brooke Crothers)

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Meteorites: Best Places to See Them Up Close

The meteorite that touched down in central Russia on Friday sent many people running, hoping to avoid getting hurt. Now, plenty of others will be running in search of valuable meteorite pieces, which can be filled with precious metals.

Although it can be cost prohibitive to collect them, museums and other tourist sites offer an inexpensive way to admire space rocks. (Related: Asteroid Impacts: 10 Biggest Known Hits)

Here are five noteworthy meteorites from around the globe.

1. Hoba Meteorite

Where is it: Right where it landed, in Namibia, South Africa. It was declared a National Monument in 1955.

Specs: This is the largest single meteorite ever found and the largest slab of naturally-occurring iron ever discovered on Earth's surface. The Hoba Meteorite weighs 60 tons and measures roughly nine feet wide by nine feet long, with a depth of three feet.

Origin: The Hoba is thought to have fallen through Earth's atmosphere 80,000 years ago, but it wasn't discovered until a farmer came across it in 1920. Despite its size, the meteorite left no impact crater, which scientists are still trying to explain. Many believe that the combination of its shape and the Earth's atmosphere must have significantly decreased the speed at which it was traveling before it crash-landed.

2. El Chaco Meteorite

Where is it: After an attempt to move the rock to Germany was blocked in 2012 by Argentine citizens and scientists, El Chaco and the rest of the pieces sit comfortably in the El Chaco province in northeastern Argentina.

Specs: The El Chaco Meteorite is one of many fragments of a group of iron meteorites called Campo del Cielo. Weighing over 37 tons, it is not only the largest fragment of that group but also the second-largest single-piece meteorite. The combined weight of the fragments discovered far exceeds 60 tons, which would have allowed it to steal the Hoba's mantle of largest meteorite found on Earth.

Origin: The meteorite was believed to have landed in the northeastern part of Argentina as part of a meteor shower sometime between 4,000 and 5,000 years ago.

3. Willamette Meteorite

Where is it now: The American Natural History Museum in New York

Specs: Weighing 15.5 tons, the iron Willamette Meteorite is the largest ever found in the United States. It is also the sixth-largest in the world.

Origin: Although discovered in Oregon in 1902 by a miner named Ellis Hughes, the pitted meteorite is believed to have crashed into Earth at least a million years ago, the result of an iron-nickel core of a planet or moon shattering in a stellar collision. It is revered by an American Indian tribe known as the Clackamas Chinook, who lived in Willamette Valley prior to European settlement.

4. Ahnighito, also known as the Tent

Where is it: The American Natural History Museum in New York

Specs: Ahnighito weighs in at 31 tons and is the largest meteorite ever moved by man.

Origin: The meteorite is one fragment of the massive Cape York Meteorite that was thought to hit Earth over 10,000 years ago in an area that is now northwestern Greenland.  Once belonging to the native Inuit tribe, the chunk of iron was coveted by many different people. It wasn't until 1897 when explorer Sir John Ross risked everything to take the Tent to New York. He had to manually slide the rock onto his ship, making it the ultimate battle of man vs. nature—with man coming out on top.

5. Bacubirito Meteorite

Where is it: It is currently on display at the Centro de Ciencias building in Culiacan, a city in northwestern Mexico.

Specs: The Bacubirito Meteorite weighs 24 tons—much smaller than the ones described above—but measuring 14 feet across, it is one of the longest meteorites ever found.

Origin: The meteorite was discovered in 1863 by geologist Gilbert Ellis Bailey and is considered one of Mexico's most famous tourist attractions.

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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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