User:Monspogi

An Oracle for Our Time, Part Man, Part Machin By GEORGE JOHNSON IN the 12th century A.D., when the Arabic treatise “On the Hindu Art of Reckoning” was translated into Latin, the modern decimal system was bestowed on the Western world — an advance that can best be appreciated by trying to do long division with Roman numerals. The name of the author, the Baghdad scholar Muhammad ibn Musa al-Khwarizmi, was Latinized as Algoritmi, which mutated somehow into algorismus and, in English, algorithm — meaning nothing more than a recipe for solving problems step by step.

It was the Internet that stripped the word of its innocence. Algorithms, as closely guarded as state secrets, buy and sell stocks and mortgage-backed securities, sometimes with a dispassionate zeal that crashes markets. Algorithms promise to find the news that fits you, and even your perfect mate. You can’t visit Amazon.com without being confronted with a list of books and other products that the Great Algoritmi recommends.

Its intuitions, of course, are just calculations — given enough time they could be carried out with stones. But when so much data is processed so rapidly, the effect is oracular and almost opaque. Even with a peek at the cybernetic trade secrets, you probably couldn’t unwind the computations. As you sit with your eHarmony spouse watching the movies Netflix prescribes, you might as well be an avatar in Second Life. You have been absorbed into the operating system.

Last week, when executives at MySpace told of new algorithms that will mine the information on users’ personal pages and summon targeted ads, the news hardly caused a stir. The idea of automating what used to be called judgment has gone from radical to commonplace.

What is spreading through the Web is not exactly artificial intelligence. For all the research that has gone into cognitive and computer science, the brain’s most formidable algorithms — those used to recognize images or sounds or understand language — have eluded simulation. The alternative has been to incorporate people, with their special skills, as components of the Net.

Go to Google Image Labeler (images.google.com/imagelabeler) and you are randomly matched with another bored Web surfer — in Korea, maybe, or Omaha — who has agreed to play a game. Google shows you both a series of pictures peeled from the Web — the sun setting over the ocean or a comet streaking through space — and you earn points by typing as many descriptive words as you can. The results are stored and analyzed, and through this human-machine symbiosis, Google’s image-searching algorithms are incrementally refined.

The project is still experimental. But the concept is not so different from what happens routinely during a Google search. The network of computers answering your query pays attention to which results you choose to read. You’re gathering data from the network while the network is gathering data about you. The result is a statistical accretion of what people — those beings who clack away at the keys — are looking for, a rough sense of what their language means.

In the 1950s William Ross Ashby, a British psychiatrist and cyberneticist, anticipated something like this merger when he wrote about intelligence amplification — human thinking leveraged by machines. But it is both kinds of intelligence, biological and electronic, that are being amplified. Unlike the grinning cyborgs envisioned by science fiction, the splicing is not between hardware and wetware but between software running on two different platforms.

Several years ago, SETI@home became a vehicle for computer owners to donate their spare processing cycles for the intense number-crunching needed to sift radio-telescope data for signs of extraterrestrial life. Now a site run by Amazon.com, the Mechanical Turk (www.mturk.com), asks you to lend your brain. Named for an 18th-century chess-playing automaton that turned out to have a human hidden inside, the Mechanical Turk offers volunteers a chance to search for the missing aviator Steve Fossett by examining satellite photos. Or you can earn a few pennies at a time by performing other chores that flummox computers: categorizing Web sites (“sexually explicit, “arts and entertainment,” “automotive”), identifying objects in video frames, summarizing or paraphrasing snippets of text, transcribing audio recordings — specialties at which neural algorithms excel.

(Not all of these Human Intelligence Tasks, or HITs, as Amazon calls them, involve serving as a chip in some entrepreneur’s machine. Hoping to draw more traffic to their sites, bloggers are using the Mechanical Turk to solicit comments for their online postings. In some cases you get precisely 2 cents for your opinion.)

In his 1950 paper “Computing Machinery and Intelligence,” Alan Turing foresaw a day when it would be hard to tell the difference between the responses of a computer and a human being. What he may not have envisioned is how thoroughly the boundary would blur.

How do you categorize Wikipedia, a constantly buzzing mechanism with replaceable human parts? Submit an article or change one and a swarm of warm- and sometimes hot-blooded proofreading routines go to work making corrections and corrections to the corrections.

Or maybe the mercurial encyclopedia is more like an organism with an immune system of human leukocytes guarding its integrity. (Biology too is algorithmic, beginning with the genetic code.) When the objectivity of Wikipedia was threatened by tweaking from special interests — a kind of autoimmune disease — another level of protection evolved: a Web site called WikiScanner that reports the Internet address of the offender. Someone at PepsiCo, for example, removed references about the health effects of its flagship soft drink. With enough computing power the monitoring could be semiautomated — scanning the database constantly and flagging suspicious edits for humans to inspect.

No one but a utopian would have predicted how readily people will work for free. We’re cheaper than hardware — a good thing considering how hard we are to duplicate.

Fractals support growing organs By Kimberly Patch Today scientists can regenerate tissue such as skin, but they are still figuring out how to grow replacement organs. The challenge is in coaxing cells from organs to grow into new organs rather than unstructured clusters of cells.

Researchers from Harvard Medical School, Massachusetts General Hospital and the Massachusetts Institute of Technology have found a way to impart structure to growing cells that may eventually allow for growth of entire organs.

If the method proves successful, "we can use [a] patient's own cells to create a living organ and this will remove the problems with organ rejections" and a shortage of donor organs, said Mohammed Kaazempur-Mofrad, a researcher at MIT and a senior research fellow at Harvard Medical School and Massachusetts General Hospital. This ultimate goal is still far away, he added.

Key to the method is supporting the growing cells with something akin to the circulatory system, which provides cells with oxygen and nutrients. "In order to make living replacements for large vital organs such as the liver and kidney, it is essential to integrate the creation of vasculature with the tissue engineering," said Kaazempur-Mofrad. And the growth of these vascular networks has to be highly controlled and precise, he said.

The researchers used computer-generated fractal patterns to fabricate a network of branching, microscopic tubes. Fractals are patterns that repeat at different scales. If, for instance, one portion of a fractal looks like a tree, zooming in on its branches and twigs will show that they also look like trees, and zooming further will show that their branches and twigs follow the same pattern.

These self-similar patterns are common in nature, including natural blood vessel networks, and can scale up or down in size. "Using [the] fractal concept will make it easier to mimic... nature and also to scale up our designs from one animal to another," said Kaazempur-Mofrad.

The researchers used computer chip manufacturing techniques to precisely etch the patterns onto silicon wafers to form a mold. "Microfabrication... provides a platform to generate such vascular networks with submicron, exquisite precision," Kaazempur-Mofrad said.

They used the patterned wafers to make microfluidic channels from biodegradable, biocompatible polymers, then stacked the networks to form a three-dimensional framework for growing cells.

The researchers' experiments using the prototypes showed that the frameworks can supply oxygen and nutrients to human kidney and liver cells. Ninety-six percent of the kidney cells were viable at the end of a one-week experiment and and 95 percent of the liver cells were viable at the close of a two-week experiment.

The work spans many disciplines -- it "brings together mechanical engineering, microfabrication, materials science and polymer processing, biotechnology, biology, and medicine," said Kaazempur-Mofrad.

The researchers are aiming to evaluate and characterize the method in animals within five years, said Kaazempur-Mofrad.

Kaazempur-Mofrad's research colleagues were Jeffrey T. Borenstein from Charles Stark Draper Laboratory, Wing S. Cheung, Lauren M. Hartman, Michael Y. Shin, and Joseph P. Vacanti of Harvard Medical School and Massachusetts General Hospital and Eli J. Weinberg of the Massachusetts Institute of Technology (MIT) and Charles Stark Draper Laboratory. They presented the research at the American Society for Microbiology (ASM) Conference on Bio-, Micro-, Nanosystems build in New York City on July 7 to 10. The research was funded by MIT and the Defense Advanced Research Projects Agency (DARPA).

POPULATION Population Growth The Philippine population in the early 1990s continued to grow at a rapid, although somewhat reduced rate from that which had prevailed in the preceding decades. In 1990 the Philippine population was more than 66 million, up from 48 million in 1980. This figure represents an annual growth rate of 2.5 percent, down from 2.6 percent in 1980 and from more than 3 percent in the 1960s. Even at the lower growth rate, the Philippine population will increase to an estimated 77 million by the year 2000 and will double every twenty-nine years into the next century. Moreover, in 1990 the population was still a youthful one, with 57 percent under the age of twenty. The birth rate in early 1991 was 29 per 1,000, and the death rate was 7 per 1,000. The infant mortality rate was 48 deaths per 1,000 live births. Population density increased from 160 per square kilometer in 1980 to 220 in 1990. The rapid population growth and the size of the younger population has required the Philippines to double the amount of housing, schools, and health facilities every twenty-nine years just to maintain a constant level.

Migration There were two significant migration trends that affected population figures in the 1970s and the 1980s. First was a trend of migration from village to city, which put extra stress on urban areas. As of the early 1980s, thirty cities had 100,000 or more residents, up from twenty-one in 1970. Metro Manila's population was 5,924,563, up from 4,970,006 in 1975, marking an annual growth rate of 3.6 percent. This figure was far above the national average of 2.5 percent. Within Metro Manila, the city of Manila itself was growing more slowly, at a rate of only 1.9 percent per annum, but two other cities within this complex, Quezon City and Caloocan, were booming at rates of 4 percent and 3.5 percent, respectively.

A National Housing Authority report revealed that, in the early 1980s, one out of four Metro Manila residents was a squatter. This figure represented a 150 percent increase in a decade in the number of people living in shantytown communities, evidence of continuing, virtually uncontrolled, rural-urban migration. The city of Manila had more than 500,000 inhabitants and Quezon City had 371,000 inhabitants in such neighborhoods. Moreover, rural-urban migrants, responding to better employment opportunities in peripheral metropolitan cities such as Navotas, had boosted the percentage of squatters in that city's total population.

A second major migration pattern consisted of resettlement from the more densely to the less densely populated regions. As a result of a population-land ratio that declined from about one cultivated hectare per agricultural worker in the 1950s to about 0.5 hectare by the early 1980s, thousands of Filipinos had migrated to the agricultural frontier on Mindanao. According to the 1980 census, six of the twelve fastest growing provinces were in the western, northern, or southern Mindanao regions, and a seventh was the frontier province of Palawan. Sulu, South Cotabato, Misamis Oriental, Surigao del Norte, Agusan del Norte, and Agusan del Sur provinces all had annual population growth rates of 4 percent or more, a remarkable statistic given the uncertain law-and-order situation on Mindanao. Among the fastestgrowing cities in the late 1970s were General Santos (10 percent annual growth rate), Iligan (6.9), Cagayan de Oro (6.7), Cotabato (5.7), Zamboanga (5.4), Butuan (5.4), and Dipolog (5.1)--all on Mindanao.

By the early 1980s, the Mindanao frontier had ceased to offer a safety valve for land-hungry settlers. Hitherto peaceful provinces had become dangerous tinderboxes in which mounting numbers of Philippine army troops and New People's Army insurgents carried on a sporadic shooting war with each other and with bandits, "lost commands," millenarian religious groups, upland tribes, loggers, and Muslims. Population pressures also created an added obstacle to land reform. For years, there had been demands to restructure land tenure so that landlords with large holdings could be eliminated and peasants could become farm owners. In the past, land reform had been opposed by landlords. In the 1990s there simply was not enough land to enable a majority of the rural inhabitants to become landowners. International migration has offered better economic opportunities to a number of Filipinos without, however, reaching the point where it would relieve population pressure. Since the liberalization of United States immigration laws in 1965, the number of people in the United States having Filipino ancestry had grown substantially to 1,406,770 according to the 1990 United States census. In the fiscal year ending September 30, 1990, the United States Embassy in Manila issued 45,189 immigrant and 85,128 temporary visas, the largest number up to that time.

In addition to permanent residents, in the late 1980s and early 1990s, more than half a million temporary migrants went abroad to work but maintained a Philippine residence. This number included contract workers in the Middle East and domestic servants in Hong Kong and Singapore, as well as nurses and physicians who went to the United States for training and work experience, a fair proportion of whom managed to become permanent residents. The remittances sent back to the Philippines by migrants have been a substantial source of foreign exchange.

Population Control Popcom was the government agency with primary responsibility for controlling population growth. In 1985 Popcom set a target for reducing the growth rate to 1 percent by 2000. To reach that goal in the 1990s, Popcom recommended that families have a maximum of two children, that they space the birth of children at three-year intervals, and that women delay marriage to age twenty-three and men to age twenty-five.

During the Marcos regime (1965-86), there was a rather uneasy accommodation between the Catholic hierarchy and the government population control program. Bishops served on Popcom, and the rhythm method was included by clinics as a birth-control method about which they could give information. A few Catholic priests, notably Frank Lynch, even called for energetic support of population limitation.

The fall of Marcos coincided with a general rise of skepticism about the relation between population growth and economic development. It became common to state that exploitation, rather than population pressure, was the cause of poverty. The bishops withdrew from the Popcom board, opposed an effort to reduce the number of children counted as dependents for tax purposes, secured the removal of the population-planning clause from the draft of the Constitution, and attempted to end government population programs. Attacks on the government population program were defeated, and efforts to popularize family planning, along with the provision of contraceptive materials, continued. In the early 1990s, however, the program generally lacked the firm government support needed to make it effective.