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Self-Portraits Chronicle a Descent Into Alzheimer’s

By DENISE GRADY

When he learned in 1995 that he had Alzheimer’s disease, William Utermohlen, an American artist in London, responded in characteristic fashion.

“From that moment on, he began to try to understand it by painting himself,” said his wife, Patricia Utermohlen, a professor of art history.

Mr. Utermohlen’s self-portraits are being exhibited through Friday at the New York Academy of Medicine in Manhattan, by the Alzheimer’s Association.



The paintings starkly reveal the artist’s descent into dementia, as his world began to tilt, perspectives flattened and details melted away. His wife and his doctors said he seemed aware at times that technical flaws had crept into his work, but he could not figure out how to correct them.

“The spatial sense kept slipping, and I think he knew,” Professor Utermohlen said. A psychoanalyst wrote that the paintings depicted sadness, anxiety, resignation and feelings of feebleness and shame.

Dr. Bruce Miller, a neurologist at the University of California, San Francisco, who studies artistic creativity in people with brain diseases, said some patients could still produce powerful work.

“Alzheimer’s affects the right parietal lobe in particular, which is important for visualizing something internally and then putting it onto a canvas,” Dr. Miller said. “The art becomes more abstract, the images are blurrier and vague, more surrealistic. Sometimes there’s use of beautiful, subtle color.”

Mr. Utermohlen, 73, is now in a nursing home. He no longer paints.

His work has been exhibited in several cities, and more shows are planned. The interest in his paintings as a chronicle of illness is bittersweet, his wife said, because it has outstripped the recognition he received even at the height of his career.

“He’s always been an outsider,” she said. “He was never quite in the same time slot with what was going on. Everybody was doing Abstract Expressionist, and there he was, solemnly drawing the figure. It’s so strange to be known for something you’re doing when you’re rather ill.”
Dr. Miller, Professor Utermohlen and others will lecture about art and Alzheimer’s on Wednesday at 6 p.m. at the New York Academy of Medicine. For more information: (212) 822-7272; www.nyam.org/events.
A self-portrait of William Utermohlen in 1967, top, and 2000, above.
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The Hidden Life of Paper and Its Impact on the Environment

By LOUISE STORY

MEDIA companies have published numerous articles on global warming and greenhouse emissions in recent years. Now, a couple of large publishers are starting to think about their own impact on the environment.

Time Inc. participated in a study published this year by the Heinz Center that calculated the amount of carbon dioxide emissions produced over the entire process of publishing Time and In Style.

Other magazine companies, including the Hearst Corporation, now say they are studying the Heinz report to consider the implications for their magazines, and Rupert Murdoch recently announced that the News Corporation is developing a plan to become entirely carbon neutral, meaning the company will reduce its carbon emissions and try to offset the emissions left over.

“We’ve recognized that these are issues that are important to our readers and, increasingly, important to our advertisers,” said David J. Refkin, the director of sustainable development for the Time Inc. division of Time Warner and a member of the board of the Heinz Center. “We’re starting to see a movement where becoming carbon neutral is something many companies are considering.”

•Large-scale manufacturing is, of course, better known as a source of the greenhouse gases that many scientists say cause global warming. Electric power production represents about 40 percent of emissions in the United States, and private motor vehicle use accounts for about 20 percent, said Michael Oppenheimer, a professor of geosciences at Princeton University.

Still, the paper industry is not without its impact. Because of its consumption of energy, the industry - which includes magazines, newspapers, catalogs and writing paper - emits the fourth-highest level of carbon dioxide among manufacturers, according to a 2002 study by the Energy Information Administration, a division of the Department of Energy. The paper industry follows the chemical, petroleum and coal products, and primary metals industries.

“Few people realize the sheer scale and magnitude of activities it takes to produce millions of copies of a magazine,” said Donald Carli, a senior research fellow at the Institute for Sustainable Communication, a nonprofit group in New York that is working to help advertisers estimate their ads’ greenhouse emissions. “There’s a hidden life that products have, and one of the challenges of sustainability is to make these lives known.”

The life of a magazine or a newspaper starts with trees being cut down in a forest and ends with the burning or recycling of old magazines or papers. The most harmful part of the process is paper production. Breaking down wood fiber to make paper consumes a lot of energy, which in many cases comes from coal plants.

Time Inc. and the News Corporation are ahead of most publishers in their public commitment to reducing carbon emissions. Other media companies contacted for this article- including Dow Jones, The New York Times Company and Condé Nast - would not comment on the levels of emissions produced by their publications.

“It’s something new to the industry, apparently,” said Jan Angilella, spokeswoman for Newsweek, which is owned by the Washington Post Company. “We’re working with printers and paper mills to see if there’s something more to be done.”

Recent reductions in paper size at many newspapers and declining circulation at many newspapers will, of course, also reduce the level of carbon emissions at paper mills. Numerous publications have taken steps to use more recycled paper - which helps decrease the number of trees used.

Time Inc.’s study found that greenhouse emissions from one of its paper mills accounted for 61 percent of the emissions from Time magazine and 77 percent of In Style’s emissions. In May, Time Inc. announced that it had asked the company’s paper suppliers to reduce their greenhouse gas emissions by 20 percent by 2012.

Mr. Refkin said the idea of sustainability - an emphasis on improving society and the environment for future generations - had come up recently in discussions with advertisers like Aveda, a beauty products company owned by Estée Lauder. Aveda sends sustainability surveys to publications to help decide where to place its ads. The surveys include questions about greenhouse emissions.

“As a company that advertises in magazines, we play an important role in encouraging publishers to better their environmental practices,” said Tanya Rogosheske, an advertising manager for Aveda. “Magazine publishers pay close attention to our interests and are receptive to environmental concerns. They become more receptive when they realize how important it is to their advertising revenue.”

A number of companies, including General Electric, Home Depot, Ford Motor, BP and Wal-Mart Stores, have been putting greater emphasis on reducing the environmental impact of their products. And Time Inc. admits that environmentally focused companies are particularly interested in advertising in Time Inc. magazines when they run articles and special editions about the environment.

Consumers are also becoming more aware of the impact of greenhouse emissions. Mr. Refkin of Time Inc. said he thought some of that awareness came from Al Gore’s recent movie “An Inconvenient Truth” and from coverage of Hurricane Katrina that said the hurricane’s extreme force might have been related to global warming.

“Probably five years ago, if somebody said something about carbon, the average consumer wouldn’t know what you were talking about,” said Tom Pollock, project manager at Metafore, a nonprofit environmental group. Metafore helped organize the Paper Working Group, which is trying to change paper-buying practices.

“CO2 and other greenhouse gases are subjects that people are looking to now since global warming is more and more in the public eye,” Mr. Pollock said.

Time Inc. is the only media company that is a member of the Paper Working Group, which also includes McDonald’s, Starbucks and Bank of America.

One way companies can become carbon neutral is to buy offsets: guarantees that carbon-lowering actions like planting trees will take place to make up for greenhouse emissions. If Time Inc., for example, wanted to buy offsets to make up for the emissions from Time magazine, it would cost about $2,500 weekly, Mr. Refkin said. Time’s study found that an average copy of Time caused about 0.29 pound of greenhouse gas emissions.

It is unclear whether In Style’s and Time magazine’s levels of greenhouse gas emissions are representative of other publications because emissions depend heavily on the source of paper. Time does not currently plan to become completely carbon neutral in the future, Mr. Refkin said.

•One In Style advertiser is currently creating a way for it to pay for its own carbon offsets. John Hardy, a luxury jewelry company based in Bali, has formed a partnership with the Institute for Sustainable Communication to request that publishers release information on their paper and printing sources. Mr. Carli of the institute will then estimate the total carbon emissions for all of John Hardy’s advertising across several publications.

Mr. Carli plans to develop a repository of information about many publications’ practices so that he can give greenhouse gas estimates to any other advertiser that also wishes to offset the emissions from its ads.

Mr. Carli estimates that John Hardy’s advertisements this year account for roughly 451 metric tons of greenhouse gases. To convert enough carbon dioxide into oxygen to offset the company’s magazine ads, the company plans to plant bamboo on the Balinese island of Nusa Penida. The bamboo needed will cover an area about the size of four football fields.

Worrisome New Link: AIDS Drugs and Leprosy

By DONALD G. McNEIL Jr.

With affordable AIDS drugs arriving in many poor countries, experts say a startling and worrisome side effect has emerged: in some patients, the treatment uncovers a hidden leprosy infection.

No one knows how widespread the problem is. Only about a dozen cases have been described in medical literature since the first one was found, in London in 2003. But AIDS specialists in Brazil, India, Africa, the Caribbean and elsewhere are reporting that some patients on life-saving antiretroviral drugs are developing painful facial ulcers or losing feeling in their fingers and toes.

And in the third world, where 300,000 new cases of leprosy were discovered last year and where 38 million are infected with the AIDS virus, the problem will inevitably get worse, experts say.

“This is just the peak of the iceberg,” said Dr. William Levis, who treats leprosy patients at Bellevue Hospital in New York City. “It’s early in the game. Most physicians don’t even think about leprosy, so there’s probably much more around than we know.”

Dr. Gilla Kaplan, a professor at the University of Medicine and Dentistry of New Jersey and one of the first to study connections between AIDS and leprosy, agreed.

Antiretroviral treatment, she said, “is going to flush out the silent leprosy by making it symptomatic.”

Because leprosy, a bacterial disease, can be treated with specialized antibiotics that are supplied free by the Novartis pharmaceutical company, there is little prospect of a worldwide epidemic or large numbers of deaths. “It’s a matter of concern for the individual patients,” said Dr. Denis Daumerie, who leads the efforts by the World Health Organization to eliminate leprosy. “It’s not a matter of concern for public health.”

Still, the disease requires taking multiple pills for six months to two years - an added burden for people who typically already take three AIDS drugs. And because the problem is little known, it often takes doctors weeks to figure out what new ill is besetting their AIDS patients.

Experts say the problem arises when the AIDS drugs cause the immune system to recover. It then generates new white blood cells that carry the bacteria from old, silent leprosy infections to the skin of the face, hands and feet.

That is a new twist on a medical paradox that has confounded tropical-disease specialists for 20 years.

In the mid-1980’s, as it became clear that AIDS was not primarily a disease of gay American men but was killing millions of people - men, women and children - in poor countries, many public health doctors prophesied that it would be a double disaster for those with leprosy.

It seemed a logical assumption since leprosy is caused by a germ from the same family of waxy-walled bacteria as those that cause tuberculosis and mycobacter avium, two major killers of AIDS patients. But it proved a false alarm.

“People expected a big surge in leprosy, but it didn’t happen,” said Dr. Diana N. Lockwood, a leprosy expert at the London School of Hygiene and Tropical Medicine.

When the predictions did not come true, she said, “we assumed that co-infected people just died before their leprosy became manifest.” The incubation period for the most easily diagnosed form of leprosy is 8 to 13 years, while the incubation period for AIDS is 8 to 10.

But leprosy in people known to have been already infected did not seem to worsen when those patients developed AIDS, too, showing that the two diseases can apparently coexist without reinforcing each other.

So it came as a shock to doctors when AIDS treatment caused hidden cases of leprosy to appear.

The first such patient described in a medical journal was Dr. Lockwood’s, a Ugandan exile in London who was being treated for both tuberculosis and AIDS, and suddenly developed a swollen lesion on his face.

“It took us a while to realize it was leprosy,” Dr. Lockwood said. “Since then, we’ve seen more cases in people from Brazil and India.”

Depending on symptoms, leprosy is often initially misdiagnosed as arthritis or lupus. Painful facial lesions, which are less common, can have many causes; in the Uganda man’s case, doctors said, his immune system probably formed nodules around bacteria next to a facial nerve.

Dr. Michael S. Glickman, a bacteriologist at Memorial Sloan-Kettering Cancer Center who treated the only co-infected case known in New York, said he too had some difficulty diagnosing his patient’s leprosy.

Dr. Glickman’s patient, a man from Burkina Faso, was suffering from advanced AIDS when he first saw Dr. Glickman six years ago, with a CD4 cell count below 10 (normal is 500 or more). As the patient recovered on antiretroviral therapy to a CD4 count of 600, he developed a lighter-colored patch of skin. Dr. Glickman noticed that it was slightly numb to the touch. Fortunately, he had once visited Dr. Levis’s clinic at Bellevue, and made the connection.

“It was so unremarkable that, if I hadn’t seen leprosy patients, I wouldn’t have known what it was,” he said.

His patient’s leprosy was eventually cured, but he had to have an unusual drug regimen because one typical leprosy drug reacts badly with the protease inhibitors taken by AIDS patients.

Treatment in cities like New York and London is relatively easy, but the real crisis, experts said, will evolve in poor countries with dual epidemics.

In French Guiana, for example, Dr. Pierre Couppié, chief of dermatology at the Central Hospital in Cayenne, said he believed that about 1 in every 500 AIDS patients would develop leprosy lesions soon after starting treatment.

Brazil has the world’s highest per-capita leprosy rate and also one of the most effective AIDS treatment programs in the developing world, and seven Brazilian cases have been mentioned in medical literature. No countrywide study has been done, but Dr. Patricia D. Deps, a leprosy expert at the Federal University of Espirito Santo in Brazil, said it was “becoming more and more common.”

“We don’t have good numbers, but we think about 2 percent of the leprosy cases in Brazil are co-infected with H.I.V.,” Dr. Deps said. The country that most worries experts is India. Not long ago, it had 70 percent of the world’s leprosy cases. Its official caseload is a bit of a mystery now. After an aggressive 20-year campaign to find and treat new cases, India officially declared leprosy “eliminated as a public health issue” last year. However, that statement was carefully crafted: it means there is a national average of lower than 1 case per 10,000 citizens, which could be as many as 100,000 new cases a year.

At the same time, with about 5.2 million people infected with the AIDS virus, India is poised to outstrip South Africa as the country with the most AIDS victims. But its epidemic began much later than South Africa’s or Brazil’s, and it has been slow to roll out AIDS treatment. As treatment grows, leprosy may surge along with it.

Other countries with high numbers of leprosy victims are Myanmar, Madagascar, Nepal and Mozambique.

But there are also great unknowns. “It depends on how good the medical system is,” Dr. Lockwood said. “For example, last year, Congo discovered 11,000 new cases.”

Novartis provides the W.H.O. with clofamizine, rifampicin and dapsone, the standard leprosy regimen, in blister packs and boxes so patients can be handed six months of treatment at a time, already divided into daily doses.

But treating leprosy in AIDS patients may turn out to be more difficult, doctors say, because rifampicin cannot be used. And treatment in wealthy countries includes more expensive anti-inflammatories, as well as thalidomide, which blocks a common inflammatory complication.

Because thalidomide causes severe birth defects, the World Health Organization opposes its use in the third world.

Doctors have long known that dormant diseases can surge as a weak immune system recovers. The threat is sometimes called “Haart attacks” - a grim pun on the medical acronym for “highly active antiretroviral therapy.”

The recovering immune system regains its ability to create fevers, flood infected tissue with white blood cells, break bacteria down into toxic waste products and build nodules around bacteria it cannot kill.

But in a weakened patient, that inflammatory response itself can be dangerous. For example, when doctors know that an AIDS patient has tuberculosis, they often try to give TB drugs for two months to suppress the bacteria before starting antiretrovirals, because the patient’s own immune attack on the tuberculosis bacteria in the lungs can be fatal.
Scientists Endorse Candidate Over Teaching of Evolution

By CORNELIA DEAN

In an unusual foray into electoral politics, 75 science professors at Case Western Reserve University in Cleveland have signed a letter endorsing a candidate for the Ohio Board of Education.

The professors’ favored candidate is Tom Sawyer, a former congressman and onetime mayor of Akron. They hope Mr. Sawyer, a Democrat, will oust Deborah Owens Fink, a leading advocate of curriculum standards that encourage students to challenge the theory of evolution.

Elsewhere in Ohio, scientists have also been campaigning for candidates who support the teaching of evolution and have recruited at least one biologist from out of state to help.

Lawrence M. Krauss, a physicist at Case Western Reserve who organized the circulation of the letter, said almost 90 percent of the science faculty on campus this semester had signed it. The signers are anthropologists, biologists, chemists, geologists, physicists and psychologists.

The letter says Dr. Owens Fink has “attempted to cast controversy on biological evolution in favor of an ill-defined notion called Intelligent Design that courts have ruled is religion, not science.”

In an interview, Dr. Krauss said, “This is not some group of fringe scientists or however they are being portrayed by the creationist community,” adding, “This is the entire scientific community, and I don’t know of any other precedent for almost the entire faculty at an institution” making such a statement.

But Dr. Owens Fink, a professor of marketing at the University of Akron, said the curriculum standards she supported did not advocate teaching intelligent design, an ideological cousin of creationism. Rather, she said, they urge students to subject evolution to critical analysis, something she said scientists should endorse. She said the idea that there was a scientific consensus on evolution was “laughable.”

Although researchers may argue about its details, the theory of evolution is the foundation for modern biology, and there is no credible scientific challenge to it as an explanation for the diversity and complexity of life on earth. In recent years, with creationist challenges to the teaching of evolution erupting in school districts around the country, groups like the National Academy of Sciences, perhaps the nation’s pre-eminent scientific organization, have repeatedly made this point.

But the academy’s opinion does not matter to Dr. Owens Fink, who said the letter was probably right to say she had dismissed it as “a group of so-called scientists.”

“I may have said that, yeah,” she said.

She would not describe her views of Darwin and his theory, saying, “This isn’t about my beliefs.”

School board elections in Ohio are nonpartisan, but Dr. Owens Fink said she was a registered Republican. Her opponent, Mr. Sawyer, was urged to run for the Seventh District Board of Education seat by a new organization, Help Ohio Public Education, founded by Dr. Krauss and his colleague Patricia Princehouse, a biologist and historian of science, and Steve Rissing, a biologist at Ohio State University.

At the group’s invitation, Kenneth R. Miller, a biologist at Brown University, will be in Ohio today through the weekend campaigning for other school board candidates who support the teaching of evolution. Dr. Miller, an author of a widely used biology textbook, was a crucial witness in the recent lawsuit in Dover, Pa., over intelligent design. The judge in that case ruled that it was a religious doctrine that had no place in a public school curriculum.

After that decision, Dr. Owens Fink said, the Ohio board abandoned curriculum standards that mandated a critical look at evolution, a decision she said she regretted. “Some people would rather just fold,” she said.

But Dr. Miller said it was a good call, adding, “We have to make sure these good choices get ratified at the ballot box.”



Rays and Neutrons, for Art’s Sake

By WILLIAM J. BROAD

VIENNA - Eager for precision in a field notorious for ambiguity and frustration, curators at top museums in Europe and the United States have long reached for the instruments of nuclear science to hit treasures of art with invisible rays. The resulting clues have helped answer vexing questions of provenance, age and authenticity.

Now such insights are going global. The International Atomic Energy Agency, a United Nations unit best known for fighting the spread of nuclear arms, is working hard to foster such methods in the developing world, letting scientists and conservators in places like Peru, Ghana and Kazakhstan act as better custodians of their cultural heritage.

“It’s very exciting,” said Matthias Rossbach, an agency official who helps direct the endeavor. “I learn so much.”

The agency runs the program as an adjunct to its global advancement of nuclear and related technologies for peaceful uses. In a way, it is one of the carrots meant to offset the intrusive policing that the agency does around the world to try to make sure nations refrain from secretive cheating in pursuit of nuclear arms.

Here at the agency’s headquarters, in late September at its annual conference, Dr. Rossbach and colleagues set up a booth to publicize the program and took time to explain analytic gear and its applications to a reporter and delegates from the agency’s 140 member states. The booth brandished the team’s credo: “Protecting the Past for the Future.”

In a nearby building, beneath a rotunda decorated with flags from around the world, a display featured some of the collaboration’s recent findings. Exhibited were dozens of scientific papers and abstracts describing how research projects had used the nuclear methods to address historic and artistic riddles.

For instance, Chinese scientists had fired the subatomic particles known as neutrons at ancient pottery from the Tang dynasty, which ruled China from A.D. 618 to 906. The analysis is helping them uncover the artworks’ origins in regional workshops.

In an interview, Feng Songlin, a scientist at the Institute of High Energy Physics in Beijing, said he found the agency’s program “very helpful for Chinese archaeology research and for me.” He said it had helped him ascertain the best analytical methods, prepare samples and learn how to interpret the findings.

Mexican scientists have also applied such methods to colonial-era pottery. Pieces once thought to have been imported from Spain turned out to have been made locally.

Dr. Rossbach said his own part of the collaboration extended to 15 countries, involved about 60 scientists and would run from 2005 to 2008 at a cost of about $230,000. His regular job involves no nuclear arms policing but rather helps industries use atomic technologies.

“We don’t have a lot of money,” he said as delegates looked around the booth. Even so, he added, his art collaborators were accomplishing much. “It’s exciting to see the progress.” Dr. Rossbach said that during the annual conference, he and his colleagues were repeatedly meeting to compare notes and discuss plans for future investigations.

The methods they use, some of the most fundamental in nuclear science, include neutron activation analysis, proton-induced X-ray emission, accelerator mass spectrometry and X-ray fluorescence spectrometry. In many cases, developing states have already acquired some of the expensive technologies in efforts to aid the analytical work of industries and governments, so the added costs of art analysis can be relatively low.

The advances are striking because the world of art, when limited to its own techniques, often finds itself hard pressed to achieve basic goals like verifying the origins of pieces, especially very old ones. The standard historical approach of comparing style and iconography, even when coupled with painstaking detective work in archives and distant collections, has often proved inconclusive or at times even deceptive.

The atomic methods, some applied to artistic analysis for the first time in the 1970’s and 80’s, have revolutionized the field of art history.

For instance, the Metropolitan Museum of Art in New York gained a wealth of insights into the provenance of old sculptures in its collection, including some sculptured heads separated from torsos during the French Revolution. The trouble arose when radicals, mistaking statues of religious figures for royalty, developed a taste for decapitation.

The museum’s detective work began at a nuclear reactor, where operators would bombard detached bits of the artwork with speeding neutrons. The resulting showers of gamma rays revealed the presence of trace elements in distinct patterns.

These identifying signatures let museum curators make matches with the similarly revealed signatures of European churches, quarries and carvings. For instance, they recently found that one of the sculptured heads in a current exhibition, “Set in Stone: The Face in Medieval Sculpture,” came from a quarry that supplied statuary to either Notre Dame or another 13th-century Parisian church.

The show features a companion exhibit on how neutron activation analysis can help solve the mysteries of provenance.

The Louvre in Paris has a very long accelerator in its basement that fires subatomic particles at artwork to discover compositional clues. Maria Filomena Guerra, a specialist there in ancient gold artifacts, traveled to Vienna last month to help the international atomic agency with its outreach program.

The agency is now fostering the development of such techniques in Hungary, among other countries. In Budapest, scientists are using a cousin of the neutron technique to study Stone Age pottery, including a graceful bowl from a cave in the Bukk mountains. The method is known as prompt gamma activation analysis.

The Hungarian scientists are using the gamma method to compare pottery from eight sites with a variety of clay samples in hope of establishing where the pots arose. The trace elements so far identified include vanadium, neodymium, samarium and gadolinium.

The scientists, Zsolt Kasztovszky, Katalin Brio and Katalin Gherdan, plan to expand the number of investigated sites and soils to produce a comprehensive portrait of artistic evolution in Stone Age Hungary.

Despite the chaos of war, Lebanese scientists recently traveled to Vienna to continue their investigations. In Beirut, they made use of a particle accelerator at the Lebanese Atomic Energy Commission that spews out ions, or electrically charged atoms. They fired these at clay storage jars of antiquity that were used to hold things like wine, olive oil, honey and fish.

The speeding ions caused the amphorae to glow in characteristic X-rays that revealed, again, distinctive patterns of elements, including gallium, strontium, zirconium and niobium.

Preliminary results of the signature analysis, they reported, linked an amphora found in France to pottery made in Beirut during the Roman period. Another analysis discovered family relationships between Beirut ceramics and those in Syria at Amrit and Ras-al-basit.

Mohamad Roumie, a nuclear physicist at the Beirut center, called the agency’s program “a good opportunity to learn and to see what is new.” He said, for instance, that he had learned a lot about computer programs that can make interpretative results more precise.

Dr. Rossbach of the international atomic agency said he had recently administered a kind of proficiency test to the program’s members. They were sent bits of powdered Chinese porcelain for analysis, and the results they obtained were then compared with the agency’s findings. “It was,” he said, “like a teacher grading a report. The objective was to help them improve their method.”

At the booth, other scientists from the agency spoke of its recent aid to foreign analysts.

“In developing countries, many laboratories are asked to help” address questions of art, said Mohammad Haji-Saeid, a physicist. “So they approach the agency for support and after that will become the service provider to their national museum.” Peru, he said, had recently asked for such aid.

At the booth, the scientists had set up one of their instruments, a portable X-ray fluorescence spectrometer, a device little bigger than a golf bag. When in operation, its beam of X-rays stimulates material under observation to glow at various wavelengths, allowing the identification of constituent elements.

The method is cheaper, easier and faster than the neutron technique, though slightly less precise. The scientists said the agency had developed the portable device for use in art museums, and they demonstrated how it worked by training it on a piece of painted canvas.

To the naked eye of an observer, admittedly no art expert, the paint looked dull and drab, almost too plain for words. But the X-rays revealed a kaleidoscope of pigment elements, rendered on the computer monitor as a series of wiggly lines. The scientists identified the peaks as sulfur, calcium, titanium, iron and zinc. Such chemical signatures, they said, could help confirm whether the pigment and painting were actually made at an advertised date, because paint formulas often changed over the decades. In this case, the paint was modern.

“All these blueprints and technical details are available cost free to all member states,” Dariusz Wegrzynek, a physicist who leads the X-ray fluorescence lab, said of the machine. States that have inquired, he said, include Syria and Poland.

Dr. Rossbach said the program excited him because in the process of teaching he discovered so much about global art as well as its diverse ranks of scientific custodians.

“I’ve learned about pottery in China and icons in Poland,” he said. “I know the techniques they’re using and can discuss whether they’re doing it right. So that, I think, is a very good exchange.”



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