May 19th, 2010

[LINK] "Did the Eradication of Smallpox Accidentally Help the Spread of HIV?"

Various studies over the past decade have demonstrated that genes responsible for helping some people--northern Europeans, mainly--resist the progression of HIV/AIDS and save others from infection entirely thanks to the selective effects of an infectious disease. Some have suggested that the disease was the Black Death of the 14th century, but others suggest that probably more likely a disease endemic for centuries like smallpox. This last hypothesis makes this news item believable to this layman.

With smallpox largely eradicated around the world, health organizations phased out the smallpox vaccine between the 1950s and 1970s (the last natural case of the disease was seen in 1977, in Somalia). During that span, Raymond Weinstein says, the AIDS crisis broke out in force. And in a study in BMC Immunology, he argues those two events could be connected.

Supposing that smallpox vaccination could have some effect on a person’s susceptibility to HIV, researchers led by Weinstein tested the idea on cells in a lab. They took immune cells from 10 people recently vaccinated against smallpox and 10 people never vaccinated. HIV, they found, was five times less successful at replicating with the cells of vaccinated people.


The researchers believe vaccination may offer some protection against HIV by producing long-term alterations in the immune system, possibly including the expression of a receptor called CCR5 on the surface of white blood cells, which is exploited by the smallpox virus and HIV [BBC News].

Any finding that expands knowledge of how HIV replicates could be an important one. And while this small study can’t prove Weinstein’s assertion is correct, the argument is, at the very least, plausible.

As commenters note, correlation isn't causation. Leaving aside the multiple other factors responsible for the HIV/AIDS pandemic, like the mass movement of people across countries and continents, the effects of smallpox vaccinations are said to fade over a decade; assuming that people were vaccinated as children, by the time they became sexually active the vaccine's effects would have wore off. Still, it's an interesting correlation.

[LINK] "Mapping the Demographics of American English with Twitter"

Language Log's Mark Liberman has posted the results of a recent study he conducted about language use in the Untied States. It turns out that Twitter does a great job of letting people track the use of colloquial language.

It took me a while to really make sense of Twitter. For the longest time, it was (to me) the stomping ground of 14-year-olds and Ashton Kutcher, each issuing a minute-by-minute feed of their lives. Around the time Twitter arrived, however, I had just had a breakthrough on YouTube's enormous popularity - it was only after watching a dozen different videos of the Super Mario Brothers theme song performed a dozen different ways that I finally got it: I may not care about cats playing the keyboard or wedding parties dancing down the aisle, but somebody does, and without a distribution system for people to broadcast whatever their hearts felt like, I never would have had my life improved by that kid with the beatboxing flute or the one with the double guitar.

So I waited for a similar breakthrough with Twitter. It came, at long last, after I realized that it was exactly what I first thought it was: 14-year-olds (and Ashton Kutcher) chronicling the minutiae of their lives. It is colloquial language, constrained by 140 characters: everyday conversations about waiting in line at the grocery store, your flight just landing at ORD, what to do this Saturday night, "omg did u see hr dress?" In spurts it is, of course, much more than that, as its use during the protests of the 2009 Iranian election proved, but in its unmarked use, it's the language of how millions of people across the world talk to their friends.

To say Twitter is colloquial is putting it lightly. "Brother," for example, occurs in Twitter data during the week of May 10-17, 2010 with an average frequency of once every 7,338 words, not too distant from its frequency in its closest cousin, the Corpus of Contemporary American English (once every 9,405 words). The difference for "bro," however, is much more dramatic: in the Twitter data during that same period, it occurs once every 5,833 words (more frequently, in fact, than "brother"), while in the COCA it occurs once every 757,575 words - two orders of magnitude less frequently.

In April 2010, Twitter had approximately 106M registered users. The volume of data that flows through the Twitter pipe dwarfs any other publicly available linguistic corpus in existence (except the web itself), and unlike fixed corpora, it still flows. Such a huge dataset has proven itself to be a fertile resource for a number of natural language processing tasks (such as trend detection and sentiment analysis), but its value as a collection of colloquial language begs to be used for lexicography as well: if the purpose of a dictionary is to record actual usage, then Twitter data allows us to broaden the scope of our corpus beyond newswire, literary works and other forms of privileged publication and include the unedited language of everyday folks as well.

Liberman covers all manner of demographics--estimated age, confirmed location, interests. It's a great post.

[LINK] "Unseen City: The Toronto Reference Library"

The latest installment in Torontoist's Unseen City series is Steve Kupferman's post describing the Toronto Reference Library, behind the scene.

Alone among the city’s large indoor hangouts, the Toronto Reference Library (TRL) has the distinction of being publicly-owned, and publicly-minded. In accordance with the building's mandate, it has a friendly public face: a tremendous central atrium and soothing ground-floor fountains give its study areas a characteristically relaxed, uncluttered appearance, and a $34 million renovation, already in progress, promises to make things even more inviting. The TRL is an enormous free Wi-Fi hotspot, a popular event space, and the administrative hub of one of the world’s largest public library systems. Aside from all that, it’s also a repository for a massive collection of printed material. You wouldn't know it, though, unless you'd paid a visit to the floors between the floors.

Though the TRL keeps some of its more-than-1,600,000 items on open shelves for the public to browse, about two-thirds of its holdings are in closed stacks. These stacks are located in locked areas on the southeast and northwest ends of the building, which visitors seldom see.

We meet Liya Shi and Dale Page at the TRL's front security desk. Liya is an operations supervisor who has been with the Toronto Public Library for over twenty years. Dale is a librarian with almost twenty-five years at Toronto Public Library, though not all of those were spent at the Reference Library. We're joined by Edward Karek, a Toronto Public Library public relations officer.

We're led past the familiar rows of internet terminals on the ground floor, which people line up to use throughout the day, through a nondescript door with an electronic lock. Suddenly, we're in a hallway that doesn't look like it belongs in the same building as the TRL's cushy, magenta-carpeted sitting area. The walls are plain white brick, and the lighting is harsh. We cram into a steel elevator and Karek jabs a button. And then, moments later, we enter the closed stacks.

It gets more exciting from there. Go, read.

[LINK] "Sable Island poised to become national park"

Sable Island three hundred kilometres southeast of Nova Scotia, a giant sand dune really, 42 kilometres long but only 1.5 kilometres at its widest, that stands out for its unique ecology including the feral Sable Island pony and a rich history as an outpost for wreckers and a site for numerous failed attempts at colonization. It's a fragile environment, and a unique environment. Fortunately, it's about to gain protection by becoming a national park.

Federal Environment Minister Jim Prentice said the process to make the ecologically sensitive spit of land in the North Atlantic a national park will begin next month with public consultations.

The island, about 300 kilometres southeast of Nova Scotia, is known as the Graveyard of the Atlantic, because it is ringed by 300 years of ship wrecks. At least 223 ships are known to have wrecked off the island.

Sable Island is also home to about 400 wild horses, descendants of animals brought to the island during the late 1700s.

The island is also a breeding ground for seals and birds, including the endangered Ipswich sparrow.

It is a fragile habitat, and Prentice said making the 40-kilometre strip of sand dunes a national park will give it the protection it needs.

"By having Sable Island designated as a national park, we have the greatest protection possible," he said in Ottawa.

Visits to the island will be restricted on account of the ecological fragility, although I hope that the federal government won't yield to the demands of hopeful potential ecotourists.

[LINK] "For Rwandan Students, Ethnic Tensions Lurk"

Josh Kron's article explores how the Rwandan governments efforts to close down public discussions about the Hutu-Tutsi differences that resulted in the 1994 Rwandan genocide has led to a displacement of these differences to areas as diverse as preferred second language and policies which punish students for dissenting from the official line.

The 1994 genocide, when Hutu death squads massacred hundreds of thousands of minority Tutsis and moderate Hutus, is never far away. At the university, where Hutus and Tutsis live and study side by side, many students are either relatives of the killers or relatives of the victims.

But the Tutsi-dominated government teaches that there are no Hutus or Tutsis, only united, patriotic Rwandans, part of a reconciliation policy enforced by laws criminalizing certain kinds of speech to the contrary.

So the students live in a surreal state of imposed silence, never talking about the one thing always on their minds: each other.

In one way, Feliciano Nshiyimana, a 26-year-old Hutu law student, is a paradigm of President Paul Kagame’s reconciliation efforts. At the crowded and competitive campus, where students sleep four to a room, two to a bed, he shares a bed with a Tutsi genocide survivor. Listening to MP3s on his laptop in his room, surrounded by toiletries, course printouts and posters of the Manchester United soccer team, he says that conversations among his roommates are delicate, but that they generally get along.

“Background is losing importance,” he said, but added, “If you have an ideology, you hide it.”

While students make acquaintances based on their interests, he says, campus life ultimately divides itself along linguistic lines, and friendships across those lines are rare.

“Linguistic lines,” in this case, is code for the ethnic groups that dare not speak their names. Although the linguistic differences are not cut and dried, for students “French speakers” means Hutu and “English speakers” means Tutsi, specifically those who returned from refugee life in English-speaking Uganda after 1994 and now run the country.

Such code has evolved in the face of the governing party’s efforts to keep peace and power by papering over ethnic identity and pushing a cult of nationalism.

[LINK] "Miniature Nuclear Plants Seek Approval to Work in U.S"

Noel, Will, Jussi: what do you think about this news item?

Manufacturers of refrigerator-sized nuclear reactors will seek approval from U.S. authorities within a year to help supply the world’s growing electricity demand.

John Deal, chief executive officer of Hyperion Power Generation Inc., intends to apply for a license “within a year” for plants that would power a small factory or town too remote for traditional utility grid connections.

The Santa Fe, New Mexico-based company and Japan’s Toshiba Corp. are vying for a head start over reactor makers General Electric Co. and Areva SA in downsizing nuclear technology and aim to submit license applications in the next year to U.S. regulators. They’re seeking to tap a market that has generated about $135 billion in pending orders for large nuclear plants.

“We’re building iPhones when the nuclear industry has traditionally built mainframe computers,” said Deal. Hyperion has more than 150 purchase commitments from customers such as mining and telecom companies, provided its technology gets licensed for operation, he said.

[. . .]

While utility-scale reactors cost about $2.3 billion apiece and produce 1.2 gigawatts of power, Hyperion’s price tag is $50 million for a 25-megawatt reactor more comparable to a diesel generators or wind farms.

Transportable by truck, the units would come in a sealed box and work around the clock, requiring less maintenance than a fossil fuel plant, the developers say. They’d cost 15 percent less per megawatt of capacity than the average full-scale atomic reactors now in on the drawing board, according to World Nuclear Association data.