Flooding in Piazza San Marco, Venice

Venice is sinking, and the nearby Adriatic sea—like the global sea level—is rising. The city could, some estimates suggest, be underwater by the end of the century. Much of the trouble is due to Venice’s precarious, low-lying position in the middle of a lagoon, but human activity in the area has played a role in the city’s subsidence, as well. As Scott K. Johnson explains at Ars Technica:

The pumping of shallow groundwater in the mid-1900s also contributed to the problem. Water in the pores between grains of sediment provides pressure that bears some of the load. When pore pressure decreases, or water is removed completely, grains can be packed together more tightly by collapsing the pore spaces. As sediment is compacted, the land surface drops. While the effect was small (less than 15cm), Venice doesn’t have much wiggle room.

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The peripatetic magnetic south pole.

A hundred years after Robert Scott‘s disastrous mission to the South Pole, a pair of Kiwi scientists are traveling to his observation hut today to continue the work he began there: tracking the Earth’s magnetic field. Since 1957, New Zealand has measured the field at Scott’s base every five years, accruing data that, along with measurements from other, more comfortable sites around the world, helps maintain the model used by NATO and nations’ defense departments for navigation.

The planet’s magnetic field needs tracking because it is shifting: the magnetic south pole has been traveling northwestward at a rate of 6 to 9 miles a year for the past century. (The geographic South Pole is somewhere altogether different.) This shift occurs because the mass of molten metal that makes up the Earth’s outer core is in a constant state of turmoil, and the  the poles could veer off in another direction at any time. Intriguing, the magnetic field has also been getting weaker since the 1800s. But whether that means the poles will flip at some point in the future—it’s happened before!—or whether it will start getting stronger again very soon is a mystery.

[via Nature News]

Image courtesy of NOAA

The holidays are hard on Christmas lights. Exposed to the vagaries of small nephews and exuberant pets, most strings will experience a few casualties, and while a missing bulb no longer means the entire set stops working, Americans still throw out millions of pounds of lights a year. Adam Minter, who’s writing a book on the globalization of recycling, describes exactly what happens to your old lights when they’re shipped over to a concern in China, which, ironically, makes better use of minced-up lights than any US company could.

Workers untangle the lights and toss them into small shredders, where they are chopped into millimeter-sized fragments and mixed with water into a sticky mud-like substance. Next, they’re shoveled onto a large, downward-angled, vibrating table, covered in a thin sheen of flowing water.

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Nodding syndrome, a disease that has sickened more than a thousand children in northern Uganda since the summer, is named for its most distinctive symptom: involuntary, at times violent bobbing of the head, like someone repeatedly nodding yes or snapping out of a doze. Outbreaks of nodding syndrome cropped up in South Sudan this summer, in the same region of Uganda two years ago, in southern Sudan—not yet an independent nation—in 2001, and periodically in remote mountain villages in Tanzania. Nearly half a century has passed since the first reported case, but epidemiologists still have only a rudimentary understanding of this mysterious disease. They’ve found few hints as to what might cause it, and no effective treatments.

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If you live in the Northeast, chances are you’ve had a disappointingly balmy December so far (the snow seems to have taken a wrong turn somewhere and wound up over Texas instead). But when the air gets that snap and you  reach for the wool socks, Emily Eggleston at Scientific American has a few factoids that promise to fascinate. Here’s why wool keeps you warm:

Wool keeps out the cold because it is an excellent insulator. Crimped and crisscrossed woolen fibers create tons of little air pockets. The tiny air masses within my socks have difficulty moving in and out of the fabric. Without convective heat transfer and contact with air of other temperatures, the spaces between wool fibers maintains a steady temperature.

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A neti pot in action.

As you may have heard by now, two people in Louisiana have died from infections of brain-munching microbes after making a small, but fatal, error. While filling their neti pots, devices that send water flowing through your nasal passages to clear them out during a cold, they used tap water instead of distilled or sterilized water. Just their luck, the tap water had a few Naegleria fowleri in it, and soon, as the microbes made their way through the nasal passages to the brain, those poor folks had a lot more than a cold to worry about. The mortality rate of human Naegleria fowleri infections is 98%.

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In the form of brood parasites, the bird world has enough irresponsible moms to start a reality TV show: cowbirds, for instance, lay their eggs in other species’ nests, stab most of the hosts’ eggs to death, and then leave their offspring to be raised by the host parents. The standing explanation for this involves most host birds being not that sharp on the uptake (watch a tiny warbler fussing over a cuckoo chick ten times its size (above) and you’d think that too). But maybe, a new study suggests, it’s sometimes to the host’s benefit to let imposter eggs stay in their nests.

The researchers chose mockingbirds as their hosts and cowbirds as their parasites, because mockingbirds usually fight like crazy to keep cowbirds of their nests but get strangely quiescent once the invaders have laid their eggs, a behavior that piqued the researchers’ interest. Once all the birds in the sample population had laid, the researchers went around adding and removing eggs from nests to see whether having a certain number of cowbird eggs affected mockingbird survival. They found that mockingbird eggs that shared their digs with cowbird eggs and suffered repeated cowbird invasions were more likely to survive, apparently because when each cowbird arrived, it would stab a certain proportion of the eggs in the nest regardless of whether they were host eggs or the eggs of the previous cowbird. Letting the parasite’s eggs stay, then, means that more of the host eggs avoid getting stabbed. The researchers conclude that when there are a lot of cowbirds around and hence a high probability of multiple nest hijackings, it makes sense for mockingbird parents not to shove out the invaders’ eggs.

Nice. And with all this dubious parenting and wanton violence, it’s straight from an episode of Teen Mom meets Cops, no?

At some Subways, the sandwiches aren’t the only thing that’s
poorly constructed.

Security in the networked world of today isn’t always the easiest to understand, we’ll admit. But business owners, who are in a position of trust when it comes to customers’ debit and credit card transactions, should really be up on basic internet security. When they’re not, they literally give away their customers’ information to hackers. Case in point: about 150 Subway franchises, which, along with at least 50 other small retailers, caused 80,000 customers to lose a total of $3 million after they set up debit card scanners without proper security and encryption.

Here’s what happened: Though Subway distributes lists of security requirements to franchisees, some neglected to follow them. According to a Justice Department statement, in addition to disregarding encryption requirements, they installed cheap remote desktop software, the kind that lets a computer be accessed from another location. All hackers had to do was guess or otherwise determine the password for access, which, as all too many people have found out, isn’t very hard when your password is “password” or “12345.” Once they had that, the hackers were like kids in a candy store, and it took quite some time for anyone to notice what was going on.

It’s enough to make you take a good, hard look at your lunch joint’s manager, and, if he looks like he doesn’t know a trojan from a man in a toga, walk right back out that door.

Read more at Ars Technica.

Image courtesy of Brixton / flickr

Methadone is commonly given to people trying to kick a heroin addiction. But the long-lasting opioid is also an inexpensive, effective pain-killer. With rising costs of prescription narcotics like OxyContin, doctors are increasingly prescribing methadone to treat pain, especially to patients on Medicaid or less generous health insurance plans. From 1999 to 2005, its use in the U.S. increased more than five-fold, according to the U.S. Drug Enforcement Administration. But over the same time period, deaths associated with the drug have increased more than five times, climbing from 786 in 1999 to 4,462, according to the CDC. In Washington state alone, more than 2,100 people died after taking the drug since 2003, says says The Seattle Times.

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When we rip open a 100-calorie snack pack, few of us have an idea of how much energy that really is–or how much walking, biking, or schlepping groceries it will take to burn it off. But what if nutrition labels included descriptions of how much exercise you’d need to burn off that candy bar?

One recent study explored that possibility by testing the effects of signs describing in one of three different ways the energy contained in a sugary drink. Researchers found that a sign that said “Did you know that working off a bottle of soda or fruit juice takes about 50 minutes of running?” halved the number of drinks purchased from a drink cooler by African American teenagers, while signs that mentioned calorie count or percentage of total recommended calorie intake did not have a significant effect. Though the study was pretty small, and thus should be verified with larger studies, the effect seems plausible, given that exercise is a much more concrete measure of energy value than calories. Some health campaigns have in fact already taken up this tactic: if you’re a New Yorker, you may have noticed subway ads using exactly this strategy, linking the calories in a 20-oz soda with the three-mile walk between Yankee Stadium and Central Park. (more…)

Drugs have a habit of making their way from our bodies into the environment: they’ve frequently been found in waste water, drinking water, and rivers (not to mention on dollar bills). But they could also be rising into the air, and a new study suggests their aerial concentrations could give scientists a clue to what, exactly, is happening on the ground below. Following up on earlier research showing that cocaine was present in the air above the cities of Taranto and Rome, Italian researchers at the Institute of Atmospheric Pollution Research in Rome took about 60 samples of air in various regions and tested for a number of contaminants, including cocaine, cannabinoids (chemicals found in marijuana), and more common pollutants, like ozone and hydrocarbons. When they looked to see whether there was a correlation between cocaine concentration and addicts’ requests for treatment in particular geographical areas, they found a very strong relationship. Weaker correlations existed between cocaine concentration and police seizures of cocaine and concentration and seizure of all kinds of illicit substances.

The team is excited about the possibility of using aerial cocaine concentration to get a sense of drug use levels, a notoriously slippery thing to measure, and possibly other activities that sometimes occur in tandem with drug use, like robberies. However, their approach didn’t turn up any significant correlations between crime-related activities and cannabinoids, which is interesting—what does that mean about the social correlates of marijuana use (or, alternatively, about the fraction of cannabinoids that actually make into the air)? If you’re worried about getting high from the air, it seems unlikely that concentrations are high enough to have an effect. But who knows—that’s a question that has yet to be addressed.

[via ScienceNOW]

Image courtesy of Adam Swank / flickr

After seven months of deliberation, the US Institute of Medicine has released a report that marks a turning point in the use of chimpanzees, humanity’s closest relative, in medical research. An IOM panel found that chimpanzees were in the vast majority of cases no longer required for disease research and laid out three stringent rules against which all current and future chimp research should be judged. Within two hours, Francis Collins, the head of the National Institutes of Health, announced he had accepted the group’s analysis and would set up a committee to apply the rules to proposed and ongoing research projects funded by the NIH.

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Spiders are covered with fine hairs that can detect the faint movements of an enemy creeping closer, or a prey insect moving nearby. Scientists had long thought that these hairs functioned like the hairs humans have in our ears, which each tremble in response to a specific frequency and have to work together for us to hear sounds. But a new experiment suggests that each individual hair on a spider is capable of responding to a whole spectrum of sound, thus acting as an ear all on its own. As Dave Mosher writes at Wired:

The hairs responded best to sounds between about 40 Hz, a low rumble of bass, and 600 Hz, a car horn (humans ears can detect between 20 Hz and 20,000 Hz). That they picked up such a wide range of frequencies at all could overturn previous assumptions about how trichobothria [as the hairs are called] work.

“They operate like band-pass filters or microphones, not like the hairs in a human ear,” Bathellier said. In effect, each hair is its own ear that filters out background noise and zeroes in on biologically relevant information, such as an unwary cricket’s hopping or a spider’s sneaking.

How all these tiny “ears” work together, though, is still a mystery—further studies will have to investigate how the hairs’ vibrations affect spiders’ nervous systems.

Read more at Wired.

Image courtesy of timsnell / flickr

How do you do to measure radiation levels in the hard-to-reach forests near Japan’s Fukushima Daiichi plant? Why, fit wild monkeys with radiation sensors, of course! Researcher Takayuki Takahashi tells CNN that his team plans to fit three monkeys in early 2012 with collars that measure radiation, as well as GPS units that record location and distance from the ground. The researchers plan to leave the monitors in place for about a month, before detaching them via remote control and picking up them up to retrieve their stored data.

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This is not real grass. And that’s not a real comment, either.

Most stories written about online crowdsourcing discuss the philanthropic aspects of people around the world pitching in on a task, like helping out in a study or identifying photographed objects for the blind. Sure, the microtasks are usually tedious, but they need humans to do them and they provide an income stream, albeit a small one, to people who have no other way to make a livelihood. It’s all good, right?

Well, as it turns out, there are other, darker tasks that only humans can do. Specifically, writing spam comments, participating in online discussions to promote brands, making new social media profiles specifically to skew the conversation on a particular topic, and other, similar practices that UC Santa Barbara professor Ben Zhao calls “crowdturfing.” (That’s a portmanteau of “crowdsourcing” and “astroturfing,” the process of faking grassroots involvement.) As detailed in an ArXiv paper, Zhao and colleagues found that this “evil crowdsourcing on a very large scale” consumes the vast majority of business on crowdsourcing sites: On the second-largest such site in the US, ShortTask, 95% of the transactions were crowdturfing (the largest, Amazon’s Mechanical Turk, which actively roots out such tasks, had 12%). Zhubajie and Sandaha, major Chinese crowdsourcing sites, turned out to be 88% and 92% ‘turfing tasks, with more than a million dollars paid for crowdturfing each month on Zhubajie alone. (more…)