Concepts familiar from grade-school algebra have broad ramifications in computer science.
Arsenic a sticky problem
Early attempts to clean up arsenic-tainted wastes near Boston actually made the problem worse, liberating forms of the toxic chemical that would have remained stable if untouched. Further, the MIT scientists who discovered that link believe that arsenic continues to leach from the waste piles created in the cleanups, and is reaching lakes and a river.
Those are two conclusions from ongoing MIT research on the Aberjona Watershed, a drainage basin close to Boston that includes parts of several towns (Woburn is at its center). The work was described by Professor Harry Hemond of the Department of Civil and Environmental Engineering at a January 13 IAP talk titled "Arsenic and Old Waste: The Legacy of Old-Time Chemical Manufacturing in the Aberjona Watershed."
With respect to remediation efforts in the 1960s, Professor Hemond said, "We believe that the cleanups, in which wastes such as animal hides were bulldozed into piles, created 'bioreactors' that have resulted in the arsenic turning into a mobile form that is reaching the lakes and river."
The scientists also studied if -- and how -- the arsenic was ingested by people living in cities that are in the watershed. Working through MIT's Center for Environmental Health Sciences, they analyzed residents' hair clippings dating from the early 1950s to the present. (If ingested, arsenic concentrates in tissues with keratin.)
They did indeed find elevated concentrations of arsenic in hair samples prior to the 1960s. However, "it's not clear how these people were exposed to the arsenic," said Professor Hemond, who is director of the Ralph M. Parsons Lab. For example, the data don't support the theory that the arsenic came from well water contaminated by a polluted river on the watershed. "The higher levels could be due to other uses of arsenic at the time, such as in pesticides," he said.
From about the turn of the century until the 1930s, companies in the Aber-jona Watershed processed huge amounts of arsenic for pesticides and other products. The wastes from these activities were often simply dumped at low points of land. "At the time, some people really believed that the environment had a great capacity to assimilate wastes," Professor Hemond said.
Since then, we've learned otherwise. Today there are more than 100 hazardous waste sites in the watershed, including two Superfund sites. The book A Civil Action by Jonathan Harr describes the legal actions that arose over the Wells G&H Superfund site and "is a very good read," Professor Hemond said.
He noted that arsenic is still used today in certain manufacturing processes. For example, chromated copper arsenate is used in some treatments for preserving house decks. "Wood that's treated with these arsenic-containing compounds is probably OK as long as it stays on the deck," Professor Hemond said in response to a question from the audience. "However, sooner or later it's going to be disposed of when people tear down old decks to build new ones."
Inventions where science meets art
If you wanted to find the resonant frequencies of your internal organs, see if a supermarket shopping cart would make a good chair, or play with a robot arm that had once packaged videocassettes, the MIT Electronic Research Society (MITERS) IAP event was the place to be.
MITERS, which has encouraged computer-related experimentation for more than 20 years, displayed a handful of sculptures and inventions at its "Performing Sculpture Open House" on January 21. Among them: a fan that resembles an airplane and flies in circles, a machine that carves 3-D relief portraits in wood, a vibrating rocking chair that can be tuned to various frequencies, a shopping cart with its sides curved down to make the arms of an armchair, and a tall bicycle created and ridden at some personal risk by MITERS treasurer Timothy C. Anderson, a former research staff member in the Laboratory for Manufacturing and Productivity and currently an engineer at Z Corp. in Somerville.
Recently relocated from Building 20, where it once boasted the third-largest computer facility on campus, the club has moved toward high-tech art and exploring the intersection of art and science, Mr. Anderson said.
Its regular events include flea markets, held monthly from April through October near Kendall Square, and the Show and Tell party, which draws up to 60 people each month and donates its proceeds to charity. The next party is scheduled for Friday, Feb. 13 at 9pm in Rm N52-115 in the MIT Museum.
Holograms can be beautiful, functional -- and edible
There's the hologram as invention, the hologram as practical device and the hologram as art. Those on an IAP tour of the MIT Museum even got a taste (though not literally) of the hologram as food.
A former fellow at the Center for Advanced Visual Studies, Eric Begleiter, owns a company called LightVision that has developed a process to transfer holograms to chocolate and hard candy. Mr. Begleiter made an appearance during the January 20 tour to show off one of his creations: a chocolate lollipop emblazoned with a colorful hologram of Mickey Mouse. His products also feature Star Trek images, Valentines and Easter bunnies, among others.
The current MIT Museum exhibition showcases holograms from the field's inception in the 1940s through the latest uses of the hologram in medicine, engineering, architecture, retailing and art. The museum acquired the entire collection of the former New York-based Museum of Holography in 1993, making MIT the owner of the world's largest collection of holograms.
The tour was led by artist Betsy Connors, whose own hologram art, Lightforest: The Holographic Rainforest, an evocative collection of holographic rainforest images and sounds, is on display in the museum. Like Mr. Begleiter, she is a former CAVS fellow as well as an alumna and lecturer at the Media Lab's Spatial Imaging Group.
Another current exhibition, Unfolding Light: The Evolution of Ten Holographers, explores the work of some of the medium's first-generation artists. It juxtaposes some of their early pieces with more recent work.
Diversity series wraps up tonight
The Diversity of Thought Symposium, a four-part IAP lecture series organized by the Multicultural Planning Committee, began on a philosophical note and ends tonight at 7:30pm in Rm 2-105 with a panel addressing the nuts-and-bolts effect of diversity on classroom and intellectual life.
The series has been coordinated by student co-chairs Zhelinrentice Scott, a Sloan School sophomore, and Richard Rosalez, a senior in urban studies and planning, in collaboration with Residence and Campus Activities staff. The students on the committee include sophomores Aisha Stroman and Grace Bae of EECS, Sharmin Ghaz-navi, a sophomore in brain and cognitive sciences, and Weslynne Ashton, a junior in civil and environmental engineering.
Ms. Scott has distinct goals for the symposium, including "to raise the consciousness of the MIT community concerning race and diversity issues, and to start a dialogue that will allow each of us to acknowlege that each person, each community and each race has similar and differing qualities and that they are all valid," she said.
In the opening session, panelists Lee Perlman, lecturer in the Experimental Study Group, Judy Jackson, staff intern in the Provost's Office and former co-ombudsperson, and the Rev. Soong-Chan Rah, pastor of the Cambridge Community Fellowship Church, talked about how segregation among people and segregation of ideas persist but might be eliminated.
"What I experienced that night was uplifting to me," Ms. Jackson said. "I sensed such deeply held care and concern for what kind of life we have together here at MIT, and it came from every single student in the audience. The dialogue was engaging, and I was truly struck by the depth of insight that many of the students shared so sincerely. The atmosphere was informal, gutsy without losing respectfulness."
In the second session, Frank Tuitt, assistant to the associate dean of residence and campus activities, and Katie O'Dair, assistant dean for student activities, led a discussion of the movie, "The Color of Fear." About 30 students attended, their discussion inspired "by the film's powerful dialogue about racism," said Ms. O'Dair.
Mr. Tuitt also led facilitators in diversity training exercises in the third session.
Tonight's session, "Diversity in Academia: Beyond Affirmative Action," focuses on the role of diversity in the classroom, in learning and in intellectual inquiry. The panel will feature three MIT alumni/ae, including Darian Hendricks (SB '89), Grant Ho (SB '97) and Professor John Essigman (SM '76, PhD).
Sarah H. Wright
Pickles pass taste test
Vlasic Kosher Dills from Camden, NJ, won top honors at the first Kosher Pickle Taste-off at MIT since 1986, beating out three Israeli brands and the pride of Manhattan's Lower East Side, Gus's half-sours.
The January 14 contest, sponsored by the MIT Jewish Campus Services Corps as an IAP activity, attracted 70-80 pickle-lovers. They rated 14 brands for bouquet, color, overall flavor, texture, crispness, spice and aftertaste. The tasting was limited to sour and half-sour dills. No tomatoes, sweet gherkins or New Age concoctions like pickled carrots were allowed.
The pickles were served directly out of jars, with water and crackers provided to clear the palate between puckers. Forty-five ballots were cast.
In addition to the overall winner, prizes were awarded for the half-sours (Gus's, naturally) and the best import from Israel (Pri-Zayerek).
Robert J. Sales
Tiny shrimp tend their own seafood
These tiny creatures can't stay out of hot water, but somehow they manage to survive anyway, in one of the toughest neighborhoods imaginable.
Professor Martin Polz of civil and environmental engineering has been studying an unusual species of shrimp that live in dense clusters on and around sulfur-covered rocks near hot spots on the ocean floor, at a depth of about 10,000 feet. He wants to determine how the shrimp can possibly eke out a living at that extreme depth, where most animals -- and the food they need for survival -- exist only sparsely.
The hot spots, called hydrothermal vents, act like valves on a pressure cooker. As oceanic plates drift, temperatures within the Earth increase, sending plumes of hot, sulfur-laden water shooting up through the vents. The plumes (nearly 300ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ Celsius) heat the surrounding cold ocean water, creating, as it turns out, an ideal home for this resourceful little shrimp (Rimicaris exoculata).
"The ocean floor is a bare environment comparable to a desert, in that there's a high diversity but low density of animals. The chances of encountering anything are very, very low. But at the hydrothermal vents, we find tube worms, giant clams as big as a dinner plate and massive swarms of shrimp," said Professor Polz, who talked about the research in his IAP course on "The Molecular Ecology of Microbial Communities: A Case Study from Hydrothermal Vents."
Professor Polz, who studies the composition and dynamics of microbial communities in marine ecosystems, discovered that the shrimp are "grow-your-own" types. They've evolved an expanded carapace, or shell, and they use the inner wall of that chamber like a tiny farm to grow the filamentous, sulfur-oxidizing bacteria they eat.
By staying in the hot, sulfur-laden water, the bacteria get the substances they need and the shrimp have plenty of food without venturing into colder areas of the ocean where their predators live. It's an example of a perfect symbiotic relationship. "The shrimp graze off the bacteria in their carapace and the bacteria get an optimal growth environment," said Professor Polz.
Admissions officers know how to pick 'em
How to get into MIT in three easy steps:
1. Get all A's from ninth grade onward, especially in math and science classes, and perfect scores on the SATs and other achievement tests.
2. Be recognized as one of the best violinists or ice skaters or oil painters in the state, or preferably in the country.
3. Be hard-working, committed, socially responsible and have a great sense of humor.
Not everyone who is admitted to MIT has to have all these characteristics. But Vincent W. James, associate director of admissions and director of the Educational Council, will tell you it wouldn't hurt.
In a January 15 IAP class dedicated to unlocking "The Mysteries of Admissions," Mr. James described what it's like to be an admissions staff member faced with a mountain of paper every January.
Each admissions officer reads about 1,000 applications. They are aided by members of the MIT community, who also are invited to read and summarize applications. Each application is read at least twice.
With years of experience, Mr. James knows what he's looking for. He wants to see accomplishment, achievement, recognition, initiative and distinction. "Being smart is important, but in this atmosphere, where it's typical for an applicant to be in the top 5 percent of his or her high school class, it's not distinctive," he said.
Among the questions admissions officers ask as they review an application: How well did the applicant take advantage of his school's and his community's resources? Did she take part in summer research or academic programs? Did his extracurricular activities have an academic focus, like the Chemistry Club or the German Club? If he edited the high school paper, did he significantly change it or improve it? Does she have leadership abilities and maturity? Do people rave about her personality?
These are among the attributes that are summarized in the non-numerical index. A computer-generated number -- made up of averages of test scores, grades and class rank -- is the applicant's numerical index. Those two numbers accompany each applicant's folder to the committee of admissions officers and other administrators who determine which 1,900 of the more than 8,000 applicants will be offered admission to the next class.
An applicant who had all of the attributes listed above would score a double 5 -- the highest possible score. But the vast majority of applicants fall into a grayer area. It's up to the admissions staff to come up with a mix of people who not only meet the requirements for admission, but who also will contribute to an interesting and exciting academic community.
What came before the Big Bang?
The universe began with a big bang, but what caused the explosion itself? At a January 15 IAP session, Professor Alan Guth talked about a theory he's developed that answers that question and others associated with the beginning of time. The theory could be proved or disproved within five years or so, thanks to data from upcoming satellites, he said.
While the Big Bang theory is strong -- several of its predictions have been backed by observations -- it has some shortcomings. Enter Professor Guth's "inflation" theory, which "doesn't get rid of the Big Bang theory, but adds to it." He is the Victor F. Weisskopf Professor of Physics.
Key to inflation is a peculiar form of matter that "turns gravity on its head, creating gravitational repulsion," he said. According to inflation, a patch of this matter "that was probably more than a billion times smaller than a single proton" existed in the early universe.
The gravitational repulsion caused by this matter resulted in an exponential expansion of the universe -- inflation. "It lasted only a fraction of a second," Professor Guth said, "and at the end, the region destined to become the presently observed universe was about the size of a marble."
The end result: a "hot, dense 'primordial soup'" -- exactly what has been assumed as the starting point of the big bang. "So inflation is a prehistory of the big bang," Professor Guth said.
Inflation also explains other phenomena. For example, "although the density of matter in the early universe was extremely uniform, on a small scale there were small ripples or nonuniformities," he said. "The Big Bang theory says nothing about what created these ripples or what determined their properties. Inflation, however, has a physical answer to how these ripples originated."
Measurements of nonuni-formities in the early universe made by the Cosmic Background Explorer (COBE) satellite fit inflation predictions. Follow-up measurements made with more powerful satellites slated to go into space within the next five years "should conclusively confirm inflation, or point out errors in it," Professor Guth said.
Sages offer ethics advice for modern businesses
What does an ancient Jewish text have to say about conducting business in 20th-century America? Marketing to children and donating a portion of profits to charity are just two of the issues discussed by scholars centuries ago that are relevant today, said Reuven Z. Cohn in his IAP session "Business Ethics in the Talmud."
The Talmud, a collection of oral laws, stories and commentaries based on the first five books of the Jewish Bible, was put in written form between 70 and 600 AD, explained Mr. Cohn, the general counsel for Cayenne Software in Bedford and also a rabbi. Discussion of the sometimes puzzling literal wording updates the original oral tradition and offers some guidelines for ethical business and personal conduct, he said.
In one segment, a rabbi says, "A shopkeeper shall not distribute parched corn and nuts to the little children, because he accustoms them to come to him." This can be taken to mean that it's unethical to recruit children as customers, a point made by opponents of the recent "Joe Camel" advertising campaign, Mr. Cohn said. However, the same passage notes that "the Sages permit it." Thus, the rabbi's principle can be taken as a voluntary guideline, while the Talmud preserves each side of the issue, just as Supreme Court justices issue majority and minority opinions for each case.
Another passage comments on a Leviticus commandment saying, "you shall not reap all the way to the edge of your field, or gather the gleanings of your harvestï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ you shall leave them for the poor and the stranger." Eight chapters of the Talmud are devoted to this verse, offering interpretations of how close to the edge one may reap and who exactly is eligible for these charitable leavings.
Though subsequent writings list this unreaped portion (pe'ah) as one of the things that "has no measure," meaning it is not strictly quantifiable, the Talmud goes on to specify at least one-sixtieth of the harvest, "all in accord with the size of the field, the number of poor and the abundance of the yield."
Thus, someone who produces a great deal could offer more than a sixtieth of his net yield -- a form of voluntary progressive taxation, Mr. Cohn said. Also, leaving the pe'ah uncut means that the poor must engage in the same productive harvest work as the owner to acquire the produce -- what today might be called workfare.
Often in the Talmud, rules are argued and amended in response to everyday realities. "Things require a thought process, and it's certainly not black and white," Mr. Cohn said. The authors "work with standard human behavior, but they find ways to remind people what a better way of being would be."
Alice C. Waugh
A CO2 storage locker?
While the world debates how to end our dependence on fossil fuels, some researchers are focusing their attention on finding ways to temporarily store the 20 billion tons of carbon dioxide released annually from the burning of these fuels.
One such method is to capture CO2 at power plants -- before it gets into the Earth's atmosphere -- and disperse it deep into the ocean via a pipe extending offshore or a trawling pipe attached to a ship.
"This is only a partial, temporary solution to give us a little time to come up with viable alternatives to fossil fuel," said Eric Adams, a researcher in civil and environmental engineering. "Most of the CO2 we put in the atmosphere will eventually end up in the ocean anyway through natural processes called the biological and dissolution pumps. By putting it directly into the ocean, we're speeding up these processes and thereby reducing the rate of increase -- and hence the peak -- in atmospheric concentration."
Dr. Adams described various methods proposed for capturing and dispersing carbon dioxide into the ocean, as well as some of the pros and cons of the concept, in his IAP talk, "Can Ocean CO2 Storage Help Reduce Global Change?"
Depending on the location where it is injected, the carbon dioxide would remain in the ocean for a few centuries to more than a thousand years, before eventually mixing with the atmosphere as it reaches equilibrium with CO2 concentrations there, he said.
The biggest question is how it would affect ocean life. Studies show that injecting it into the ocean would result in localized increases in acidity, lowering the pH by about one unit in the dispersal area, according to Dr. Adams.
"But if we take the business-as-usual approach, let the CO2 rise into the atmosphere and get pumped back into the ocean naturally, the pH will decrease anyway. The key is to disperse it widely so that the pH doesn't change very much," he said.
A version of this article appeared in MIT Tech Talk on January 28, 1998.