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Election fix? Switzerland Tests Quantum Cryptography

Swiss officials will scramble vote data at one gigabit per second to determine whether this experiment lead to more reliable elections
Science Image:
 
During Switzerland's upcoming national elections, officials will use quantum cryptography to secure the network linking its ballot data entry center to the government repository where votes are stored.

Quantum cryptography, which relies on the laws of physics to ensure that encoded messages can be deciphered only by those authorized to do so, has for years promised to deliver encryption far stronger than the public key infrastructures (PKI) more commonly used today. Trouble is, there are few, if any, documented uses of this quantum technology outside of lab settings.

But this is about to change: On Sunday during Switzerland's national elections officials in Geneva will use quantum cryptography to secure the network linking their ballot data entry center to the government repository where votes are stored. Quantum cryptography relies on a highly secure exchange of the keys used to encrypt and decrypt data between a sender and a receiver, and Swiss election officials' confidence that this technology is ready for prime time will provide a strong tailwind for a technology still in its adolescence.

"This occasion marks quantum technology's real-world debut," says University of Geneva professor Nicolas Gisin. "This is the first time this is being done for a real customer who's using real data."

Indeed, researchers at the university, along with id Quantique, SA, a quantum encryption technology provider spun off by the school, are hoping the elections will provide much-needed momentum for their pilot quantum communications network called the SwissQuantum project. Headed by Gisin, with support from the Swiss National Science Foundation's National Center of Competence in Quantum Photonics Research, SwissQuantum is expected to provide an additional outlet for working out the kinks that have prevented wider use of quantum encryption technology.

Although Swiss citizens will vote using a paper ballot, information about the number of votes will be keyed into computers after the polls close. That is where the 100,000 euro ($140,000) id Quantique encryption system kicks in, scrambling the data at the blazing-fast speed of one gigabit per second and sending it from those computers to a data center run by the university's center for information technology.

With quantum encryption, the sender encodes the encryption key on an individual quantum particle, such as a photon or electron, and sends that particle via a fiber-optic line to its destination. Information about key characteristics of the particle—such as its size or level of polarization—is sent to the destination as well. If the particle that arrives is distorted in any way, it is discarded and another key is sent. This protects quantum encryption and quantum key distribution from third-party eavesdropping because a particle cannot be intercepted without changing its quantum state.

"Quantum key distribution is used as a novel method to exchange between two people a key that is then used to encrypt a message," says Jonathan Habif, a research scientist with BBN Technologies in Cambridge, Mass., a company that in 2003 worked with the Defense Advanced Research Projects Agency (DARPA) to create the world's first quantum key distribution network. "You're not transmitting a message, but rather an encryption key. The beauty of quantum key distribution is it gives you a method to exchange keys with a security method that is rooted in the laws of physics."

Quantum encryption's chief impediment has been its inability to send information great distances. Scientists at the U.S. Department of Commerce's National Institute of Standards and Technology (NIST), the U.S. Department of Energy's Los Alamos National Laboratory and Albion College in Michigan generated and transmitted secret quantum keys over 185 kilometers (115 miles) of fiber-optic cable during an experiment last year—the farthest such information has traveled. The first experimental quantum encryption prototype, created in 1991, was able to send information a mere 32 centimeters (12.6 inches).

The quantum encryption work being done in Switzerland will be an important learning experience, particularly because the technology is still in its early stages of development, Habif says. Quantum key distribution systems available today work only over short distances and require an exponential amount of computing and network resources as that distance grows. "If you give the field five to 10 years, you will see the beginnings of a scalable quantum key distribution system," he says, adding that a quantum signal cannot be amplified today because a repeater would destroy the photons and the data they carry as it inspects the photons. "You need a quantum repeater that will preserve the fidelity of the quantum information as it moves through the network." Of course, the presence of such a repeater could also weaken the sanctity of the encrypted transmission if the fiber-optic network is not properly secured.

Skeptics say that although the Swiss government's plan to demonstrate quantum cryptography is interesting, it is not likely to vastly improve the integrity of elections. "This makes no positive contribution to voting security or trustworthiness," says David Dill, a Stanford University professor of computer science and founder of the Verified Voting Foundation, a nonprofit organization pushing for the implementation of voting processes that can more easily be verified and audited. "The transmission of vote data to the central server is really one of the lesser issues. To the extent that that's a problem, it can be adequately solved at less cost and risk using conventional cryptography."

In order to have a voting system that allows for truly verifiable election results, information has to be protected from the time the vote is cast to the time it is counted and the election is certified, Dill says. So could the Swiss experience help iron out problems brought to light during the 2000 U.S. presidential election fiasco, which ended in a Supreme Court decision that ushered George W. Bush into the White House? Extremely unlikely, Dill says, noting that the U.S. still has no minimum standards for conducting federal elections that would create consistency across the country.


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Elephants Use Smell of Fear to Sort Friend from Foe

An elephant's nose (and eye) knows what's out to get it
Science Image: fearful elephants
FEAR FACTOR  Elephants lift their trunks to get a better whiff of danger.

They say elephants never forget, but their brainpower does not stop there. A new study suggests that pachyderms can distinguish threatening groups of people from those who mean them no harm.

Researchers working in Kenya presented the animals with identical red garments worn for five days either by Maasai tribesmen, who slay elephants to prove their strength and daring, or by farmers of the Kamba tribe, who leave the pachyderms in peace.

The beasts turned tail and ran after sniffing the clothing worn by the Maasai but had much less reaction to the odor of the Kamba, according to a report published in Current Biology. The same elephants responded aggressively toward unworn red robes—the traditional color of the Maasai—but not toward odorless white clothing.

"It tells us a bit about how elephants classify the world," says evolutionary psychologist Richard Byrne of the University of St. Andrews in Scotland. "Instead of treating humans as all one set, they're able to discriminate within one set."

Human minds effortlessly extract key characteristics common to groups of objects, he says, such as the redness of apples. But researchers are less sure whether animals can form similar categories.

Byrne says he, St. Andrews colleague Lucy Bates and the other team members began their experiment after talking to members of the Amboseli Elephant Research Project in Nairobi, Kenya, who told tales of odd elephant behavior.

Science Image: Maasai tribesman
SEEING RED:  In a new study, elephants ran away from red clothing worn by a Maasai tribesman, such as this Maasai dressed in traditional finery.
 
"There were a number of reports of very inquisitive and sometimes aggressive reactions of elephants toward signs of Maasai, but not towards people brandishing spears," he says.

Researchers have found that individual elephants can identify one another as strangers or old friends. Byrne says the fact that elephants seem to pick out particular cues from their environment that mark Maasai warriors suggests that the animals can actually classify whole subsets of a species based on the threat they pose.

The elephants' different reactions to smell and color make sense, he adds, because the odor of a Maasai hunter implies that he is nearby, triggering fear that sends the pachyderm packing.

"It's an innovative way of getting at the problem" of what animals know about their environments, says Karen McComb, an expert in mammal communication and cognition at the University of Sussex in Brighton, England. "The response is very appropriate to knowing what the threat was. It's suggesting they have some sort of reasonably advanced understanding of the sorts of cues that are going to be dangers."

As for what goes on in their heads and whether it resembles human consciousness, she adds, "we can only guess." 

Wikipedia "Good Samaritans'' Are on the Money

A Dartmouth study indicates that anonymous contributors are as reliable as registered contributors to the massive online encyclopedia
Science Image:
Although questions have been raised about anonymous contributors to Wikipedia, these "Good Samaritans" are as reliable a source of knowledge as those contributors who register with the site.

Open-source information repositories such as Wikipedia have changed the way knowledge is captured and disseminated, using the Internet as a perpetual worldwide editing system for a virtually unlimited digital encyclopedia. But who are the sources for the sites—and how much credence should we put in the information they provide?

Although serious questions have been raised about the reliability of the information recorded on Wikipedia, particularly by anonymous contributors, a group of researchers from Dartmouth College in Hanover, N.H., has found that anonymous and infrequent contributors to Wikipedia—whom they dub "Good Samaritans"—are as reliable a source of knowledge as those contributors who register with the site.

The concerns about the quality of information found in Wikipedia center on the nature and skills of the contributors and editors, the Dartmouth researchers say in a just-released study. Given that the creation of its content is completely open, they say, quality depends entirely on who contributes. The most reliable contributions are those that undergo the least number of changes or edits from the open-source community—and remain on the site the longest.

 

Because contributors have the opportunity to add, edit or delete whatever content they choose, preserving information from earlier versions is taken as tacit acceptance of its quality. Overall, the study says, registered users contribute more content than anonymous users, but anonymous users contribute higher quality content overall.

Researchers measured the retention rates of information posted by 7,058 contributors to the French- and Dutch-language versions of Wikipedia in March 2005. (The English-language version was too massive to adequately monitor.) At the time, the French site had 53,901 overall contributors, whereas the Dutch version had 33,217 contributors. The researchers also sampled an equal number of registered and anonymous contributors, although anonymous contributors outnumbered registered users by a ratio of 10 to one.

"Surprisingly, the reliability of the Good Samaritans shows that the hype around open source seems to be true, that there are benefits of people all around the world contributing to something for the larger public good," says Denise Anthony, a Dartmouth associate professor of sociology who worked on the study with Dartmouth associate computer science professor Sean Smith, and with former student Tim Williamson, who went on to become a programmer with Ning, Inc., a company that provides a free service for creating online social networks.

Researchers are not saying that all of the information on Wikipedia is completely accurate, but "this tells you that Wikipedia has the capability to be a good source of information," Anthony says.

The results were surprising, given that oversight over Wikipedia is minimal. Over the past decade, the development of open-source operating systems, databases and other programs has thrived thanks to the generous contributions of individuals who share nothing more than a common interest in the development of a particular program. Of course, these contributions are rarely anonymous and most open-source software projects have managers who have final say over what stays and what goes. Open-source information repositories do not require the same level of openness among its contributors.

Because open-source projects can increase the population that has access to a particular piece of information, "you can have thousands of people who each contribute one small thing," Anthony says. "We don't have other mechanisms that can do that. There have been social movements before that could move hundreds of thousands of people toward a certain goal, but none of them sustained the production of a good over time like this."

Recycling the Whole House 

 

IF the idiosyncratic, ’40s-era cottage Alice Keller bought in Shoreline, a small city just north of Seattle, had a style, it might be called classic teardown. The ceiling in one room was so low she couldn’t stand up under it. A downstairs bathroom was so narrow she had to wiggle sideways to get to the toilet. None of the windows matched.

“It was livable, and quirky,” Ms. Keller said, “but in ways I didn’t find amusing.”

The place was crying out for a wrecking ball, but Ms. Keller, a 63-year-old retired teacher of English as a second language, who has an environmentally aware conscience, didn’t want to scrap the building materials only to buy new ones. Instead of having her 1,300-square-foot house bulldozed, she hired Jon Alexander, a contractor who shared her environmentalism and was willing to dismantle the home shingle by beam, and build a replacement with the same two-by-fours.

The crew left the garage and a portion of the subfloor intact and broke the concrete driveway into chunks for a back patio. A gas water heater, fiberglass insulation and windows landed at the RE Store, a local nonprofit shop that sells used or excess construction materials. The drywall, shingles and extra concrete went to a recycling center.

Ms. Keller was able to reuse around 90 percent of the original house. “I just like reusing things,” she said. “You can end up with something with more character.”

Due to rising landfill costs, tighter recycling guidelines and the growing trend toward ecologically sound building methods, this sort of home “deconstruction,” as the practice is called, is starting to catch on. About 1,000 homes a year are disassembled this way, according to the Building Materials Reuse Association, a nonprofit educational group in State College, Pa., which reports growing interest in the practice.

Fueling that interest are efforts by cities and states across the country to stanch the flow of demolition rubble into landfills. Some 245,000 houses in the United States are razed each year, generating nearly 20 million tons of debris, according to a 1996 report from the Environmental Protection Agency, the most recent data available.

Confronted with mounting waste, the Massachusetts Department of Environmental Protection has banned brick, concrete, metal, wood and asphalt from landfills.

In San Jose, Calif. — where construction and demolition refuse accounts for 30 percent of landfill waste, according to official estimates — homeowners who apply for a city permit to demolish, remodel or build an addition have to pay a deposit based on the size and type of project. To get the money back, they must show that 90 percent of the material generated has been reused or sent to a certified recycling or reuse center. Cities including Seattle, and Chicago have also introduced measures to reduce construction and demolition waste.

Using old materials for new buildings isn’t a new idea. The Coliseum in Rome was used as a quarry to build St. Peter’s Basilica and other Roman landmarks. In the United States, families often reused building materials to save money in the early part of the 20th century, a custom that fell out of favor as the country grew wealthier in the 1950s.

Today, according to the Building Materials Reuse Association, up to 85 percent of the average house can be recycled or reused; the hard part is harvesting the materials in a way that preserves their integrity.

Unbuilding a home takes longer than leveling it the usual way and often costs more, at least initially. While almost anyone who’s watched a TLC rehab show can rip out a kitchen cabinet, unpiecing an entire house without having the roof collapse isn’t a job for the uninitiated. The Building Materials Reuse Association, which introduced a deconstruction training program in May, has certified 60 builders so far.

When Carolyn Bronstein and John Tapper wanted to dismantle a 2,500-square-foot Victorian adjacent to their house in the Southport section of Chicago, they could not find a local deconstruction contractor. They recruited Ted Reiff, a contractor and the president of a group called the Reuse People of America, based in Oakland, Calif. The couple bought the house for about $800,000, intending to knock it down so their children could have more space to play, and to make sure a developer didn’t snap up it up. 

While the standard demolition quotes were around $25,000, the couple spent $38,000 to have a contractor trained by Mr. Reiff unpiece it over six weeks last summer. They expect to come out even or better after selling door hardware, windows, appliances and other components at a salvage auction and reaping a tax deduction by donating the rest to a reuse store.

“It was cleaner and quieter than demolition,” said Ms. Bronstein, an assistant professor of communication at DePaul University in Chicago. “We didn’t have dust flying everywhere.”

Usually, the real savings comes in the reconstruction phase. Paul Pedini, the owner of the Big Dig House in Lexington, Mass., possibly the country’s most celebrated recycled dwelling, estimates he shaved at least $200,000 from his materials costs by using concrete on-ramps and steel beams recovered from the Big Dig highway project in Boston for his modernist structure.

“There were these materials and we wanted to build a house. We just put two and two together,” said Mr. Pedini, a civil engineer who was a contractor on the Big Dig. “I told them, why not keep the money you’d pay in disposal costs and give the materials to us to reuse?”

Although few home builders have access to the remains of a $14.6 billion highway project, many cities now have “reuse” stores, which sell salvaged goods — from wall sockets to vintage redwood floorboards — for 50 to 75 percent off what similar products would cost if purchased new.

There are about 1,000 such stores nationwide according to the Reuse Association, most of them nonprofits that offer tax deductions in exchange for donations of used housing materials. Habitat for Humanity International, the affordable housing organization, runs 500 such shops in 45 states, mostly selling easily recoverable accessories like cabinets, doors and flooring. Unlike architectural salvage stores, which sell marble fireplace mantels, stained glass and spiral staircases, reuse stores generally traffic in mundane items like light switches and insulation.

As with buying secondhand clothes, the challenge — and potential charm — of reuse shopping is its unpredictability. Build it Green! NYC, a reuse shop in Astoria, sells sets from nearby film studios alongside items rescued from residential demolitions. Recently, $25 diner stools from “The Knights of Prosperity,” a short-lived ABC show, were for sale alongside $40 doors from “The Sopranos” and a set of cherry-finish kitchen cabinets removed from an Upper East Side apartment. The original owners paid $18,000 to buy and install the cabinets, according to Justin Green, a founder of the store, who was asking $1,200 for the set — top and bottom cabinets as well as counters.

“I love shopping there,” said Timothy Etienne of Garden City, N.Y. “You never know what you’re going to find.”

He has purchased windows, doors and paint at the store for a second home upstate, along with a six-foot-tall wooden tepee ($30) that is now a backyard playhouse for his four daughters.

Ms. Keller, meanwhile, has been combing the RE Store in Seattle for months, trying to find secondhand glass blocks for the master bath in her new 1,600-square-foot home. She recently scavenged a double-pane glass door for her balcony and a cast-iron double sink for a craft room.

To outfit a home this way, it helps to have a retiree’s schedule.

“You have to be patient,” Ms. Keller said. “It’s the thrill of the hunt that keeps me going back.” 

Successful Malaria Vaccine Also Proves Effective in Infants

New data shows that the RTS,S vaccine is safe and effective in infants
 
Science Image: mozambican-infant-receives-vaccine
BABY BOON: A new trial has shown that vaccinating infants with RTS,S can prevent 62 percent of new cases of malaria.

A baby born in sub-Saharan Africa faces a lifetime of health risks, but none more challenging than surviving its first five years. A major reason for that is malaria, a parasitic disease spread by mosquitoes. Of the more than one million malaria deaths worldwide annually, roughly 90 percent are in children under five years of age and as many as 50 percent of the severe cases occur in babies under 18 months of age. But new results indicate that a vaccine previously shown to be safe and effective in adults and small children can also be safely administered to infants, potentially dramatically decreasing their risk of contracting the disease.

"In endemic areas, and particularly in the high-transmission areas of sub-Saharan Africa, children under one year of age carry a disproportionately high burden of disease," says physician Pedro Alonso, director of the Barcelona Center for International Health Research at the Hospital Clinic of the University of Barcelona, who led the new clinical trial. "You need to get to them and protect them as early as possible."

Researchers report in The Lancet that there were 62 percent fewer new cases of the disease among 214 infants between 10 and 18 months who had received the full three-dose course of the RTS,S/AS02A vaccine during this trial. And among all infants from a rural area in southern Mozambique who had received at least one injection, there were 35 percent fewer malaria episodes. 

"As a father and a grandfather, and not just as a doctor and a policymaker, I tell you that this vaccine can make a profound difference in our lives," says physician Pascoal Mocumbi, a former Mozambican prime minister who also had served as health minister. This "will save lives."

The clinical trial is one of many being undertaken to assess the safety of the RTS,S vaccine developed by GlaxoSmithKline (GSK). Researchers say that it caused initial pain at the injection site (the thigh in babies) but that no other serious side effects were reported. A previous study showed the vaccine, created in 1987, reduced the malaria risk of young children between one and four years by 30 percent—an inoculation that lasted for at least 18 months. The vaccine also protected 34 percent of men in a study in Gambia.

RTS,S works by fusing a protein secreted by the malaria parasite with a molecule on the surface of hepatitis B virus that the human immune system recognizes and attacks. The researchers speculate that it works much like other vaccines, especially because the amount of protection conferred depends on the amount of malaria antibodies in the blood and malaria-recognizing, disease-fighting T cells in the liver. Neither on its own is sufficient, however, according to physician W. Ripley Ballou, vice president of global clinical research and development at GSK Biologicals. "There is something really important," he says, "in having both arms of the immune system working."

A large trial to determine the overall efficacy of the vaccine in children of all ages is expected to begin late next year, assuming results from ongoing safety trials continue to be positive. That trial will enroll at least 16,000 children from as many as 10 areas in seven African countries, Ballou says. It will investigate, among other things, whether adding a booster shot later in life provides added protection.

The good news is that the vaccine appears to be effective against all strains of the malaria parasite Plasmodium falciparum, and those initially protected have not shown any rebound effects later in life. "The vaccine does not seem to protect specifically against certain parasites," says molecular biologist Joe Cohen, vice president of research and development for emerging diseases, HIV and vaccines at GSK Biologicals. But "this is a question that we will need to continue to address in further studies and even probably after the vaccine has been implemented," which could come as soon as 2011 if all trials go well.

In the meantime, researchers are encouraged that the vaccine has proved especially effective in protecting the most vulnerable population: babies. In conjunction with other proven methods—treated bed nets and DDT spraying, as mandated by the Mozambican government—it could slash malaria infections and deaths in children. "We may be seeing the synergy that we would predict would exist between vaccination and other modalities of malaria control," Ballou says.

And the vaccine may also provide broader benefits: "A vaccine acts as a magnet, drawing in multiple generations of a family for basic services when the children come to get vaccinated," Mozambique's Mocumbi says. "When we protect children we are investing for the future of our nation."

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