Editor's Note: A team of Rensselaer Polytechnic Institute students are traveling up New York's Hudson River this week on the New Clermont, a 6.7-meter boat outfitted with a pair of 2.2-kilowatt hydrogen fuel cells to power the boat's motor. Their journey began September 21 from Manhattan's Pier 84 and will cover 240 kilometers (at a projected speed of 8 kilometers per hour). After making several stops along the way, the crew expects to arrive back at Rensselaer Polytech's campus in Troy, N.Y., on September 25. This is the third of Scientific American.com's blogs chronicling this expedition, called the New Clermont Project.


The New Clermont Project crew is learning valuable lessons about what it will take to make hydrogen power not only possible but practical as well. After losing both hydrogen fuel-cell-powered boat motors Tuesday, the New Clermont spent Wednesday docked in Beacon, N.Y., while the Rensselaer students figured out what went wrong.

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In an early-morning announcement today, researchers reported that an experimental HIV (human immunodeficiency virus) vaccine effectively reduced the number of people who contracted the virus by nearly a third.

Tested in a U.S.-sponsored trial that involved more than 16,000 volunteers in Thailand, the vaccine was administered in six injected doses starting in 2006 to half of the group, and the other half received a placebo. Seventy-four people in the placebo group had contracted HIV by the end of the trial, whereas only 51 of the vaccinated group tested positive.* The injections consisted of two vaccines that had proven unsuccessful on their own: Sanofi-Aventis SA's ALVAC and VaxGen Inc.'s AIDSVAX.

The results came as a surprise to HIV-vaccine skeptics in the AIDS (acquired immunodeficiency syndrome) research field, whose numbers have increased after years of failed vaccine trials. "It's safe to say that the scientific community is caught off-guard," Mitchell Warren, director of the AIDS Vaccine Advocacy Coalition, told Bloomberg News. Before the announcement, Marie-Paule Kieny, director of the World Health Organization's Initiative for Vaccine Research, told the news service: "I don't think that there is a lot of expectation that the efficacy of this vaccine will be very high." A 2007 clinical trial of a vaccine made by Merck was stopped when researchers found that, in fact, more people who received the active vaccine (49) than the placebo (33) had contracted HIV.

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A team of Duke University researchers in Durham, N.C., is studying new ways to use the abundance of sensors contained in most smart phones (including the camera, accelerometer, microphone, GPS and Wi-Fi radio) to determine mobile users' precise locations and thereby deliver hyper-localized services. This could enable a business such as Starbuck's to text-message a coupon to a person's phone as he or she enters the coffee shop, or it could allow Wal-Mart to send shoppers a listing of sales items as soon as the store's doors slide open. Another option could be to provide blind mobile subscribers with information about where they are as they move from store to store within a mall.

The researchers argue in a paper presented today at the ACM MobiCom 2009 conference in Beijing that the increasing number of sensors on mobile phones presents new opportunities for logical localization, which is more useful to people than simply representing their location as a set of latitude and longitude coordinates.

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Population growth, now at roughly 78 million extra people per year, is the don't-go-there zone of modern environmentalism and political discourse.

But let's go there for the moment: The biodiversity crisis. The water crisis. The climate crisis. Lurking behind all these crises is at least one shared factor: human population. Species extinction? Think land clearing for agriculture to feed a growing population of 6.8 billion people. Water? The majority of water goes directly to growing that same food supply. And giving a helping hand to all these other crises as a result of all the fossil fuel burning needed to power our lives and lift billions out of poverty: anthropogenic climate change.

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Editor's Note: A team of Rensselaer Polytechnic Institute students are traveling up New York's Hudson River this week on the New Clermont, a 6.7-meter boat outfitted with a pair of 2.2-kilowatt hydrogen fuel cells to power the boat's motor. Their journey began September 21 from Manhattan's Pier 84 and will cover 240 kilometers (at a projected speed of 8 kilometers per hour). After making several stops along the way, the crew expects to arrive back at Rensselaer Polytech's campus in Troy, N.Y., on September 25. This is the first of Scientific American.com's blogs chronicling this expedition, called the New Clermont Project.

The New Clermont Project comes 200 years after Robert Fulton drove the world's first commercial steamboat, The Clermont, from New York to Albany. William Gathright, a doctoral student in Rensselaer's Materials Science and Engineering Department, began assembling the crew and resources necessary for this green-fueled tour of the Hudson earlier this year. Gathright is also pursuing a master's in management from Rensselaer's Lally School of Management & Technology.

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Paying bills or counting change may seem like basic life skills to most, but for those who are about to slip into older-age dementia, the tasks can become increasingly difficult. And as fiscal functionality begins to fail, Alzheimer's disease might be less than a year away, a new study suggests.

"Impairments in financial skills and judgments are often the first functional changes demonstrated by patients with incipient dementia," wrote the authors of the paper, which was published online today in Neurology. 

Although the relationship between money management skills and dementia has been established for some time, the researchers' focus on declining skills as an early indicator showed that once these abilities start to slip, the diagnosable disease is likely not far behind.

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Runoff from agriculture is the biggest polluter of the country's river and stream water, according to the U.S. Environmental Protection Agency (EPA), and it has been fingered for hypoxic dead zones and toxic red tide algae blooms.

But how much of that runoff makes it into people's drinking water closer to home? In agricultural areas, it can be enough to cause persistent health problems, including diarrhea and other infections, according to a report today in The New York Times.

"Sometimes it smells like a barn coming out of the faucet," Lisa Barnard, a Wisconsin resident told the Times. Barnard's well water tested positive for various contaminants and bacteria, including E. coli—which point not just to any runoff, but that coming from excess manure, according to the Times piece.

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Going without health insurance can delay when people obtain primary and preventative care, potentially resulting in poorer health. Even more gravely, a lack of private health insurance brings an increased risk of death; uninsurance is to blame for some 44,789 adult deaths across the U.S. every year, according to a new study published online today in the American Journal of Public Health.

The findings show that uninsured Americans—between the ages of 17 and 64—have a 40 percent higher risk of death than those who have private insurance. (Those enrolled in government insurance programs, such as Medicaid and Department of Veterans Affairs insurance, were excluded from the study.) About 46.3 million Americans didn't have health insurance as of 2008, according to the U.S. Census Bureau, and the number is estimated to be higher now since the recession has forced many off of employer health plans.

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The U.S. Food and Drug Administration approved the long-awaited vaccines for the H1N1 "swine" flu virus this afternoon. It is expected to be available in a month at about 90,000 locations nationwide, the Associated Press reported. 

"We will have enough vaccine available for everyone," Kathleen Sebelius, Health and Human Services Secretary, said in an address to Congress today, the AP reports. The government, which does not expect everyone to get the vaccine, has an order out for 195 million doses, but only about 45 million are expected to be available by mid-October. The announcement from the National Institutes of Health (NIH) last week that one dose is sufficient to protect against the virus means supplies will be more robust than they might otherwise have been. Nevertheless, the government is prepared to order more if necessary.

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Bathers, beware. A trip to the beach could yield more than a damaging sunburn. According to a recent study, all nine sampled beaches in Washington State contained strains of the virulent methicillin-resistant Staphylococcus aureus (MRSA) bacteria—or related methicillin-resistant coagulase-negative Staphylococci—in the sand or water.

The so-called superbug can cause severe infection and is resistant to some antibiotic treatments. It is most closely associated with hospitals, where it was responsible for nearly 9,000 patient deaths in 2005, according to a study in The Journal of the American Medical Association. It has, however, been drawing increased attention in other settings.

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