SCIENCE
Notebook

Monday, September 16, 2002; Page A09

Scientists have genetically engineered mice with fur that glows fluorescent green.

Robert M. Hoffman of AntiCancer Inc. in San Diego and colleagues were conducting research aimed at finding new ways to treat skin conditions such as acne and possibly baldness.

The researchers treated the skin of laboratory mice with an enzyme called collagenase, and then used a common virus to insert into the skin cells a gene known as GFP, which gives jellyfish their glow. Tests showed that about 79 percent of the hair follicles that grew out of the skin glowed green.

The approach could one day be used for a variety of purposes, including possibly treating baldness or permanently changing hair color.

"The approach to hair follicle genetic modification technique described in the present report gives rise to the possibility of a safe genetic modification technique in a very accessible and visible organ," the researchers wrote in a paper published online last week by the Proceedings of the National Academy of Sciences. "Both cosmetic and therapeutic genes could be delivered to hair follicles with this strategy."

A study involving DNA extracted from wild elephants' dung indicates that there are three -- not two -- distinct types of elephants in Africa.

Lori S. Eggert of the Smithsonian Institution collected elephant dung samples while working as a doctoral student with David S. Woodruff at the University of California, San Diego. She collected the dung to obtain DNA samples from the elephants, which are very difficult to see and study.

The analysis found that in addition to the long-recognized savanna elephant, and the recently recognized forest elephant of central Africa, there is a genetically distinct elephant that lives in both the forest and savanna of west Africa. The analysis indicates that elephant diverged from the others about 2 million years ago.

"Our analysis reveals several deeply divergent lineages that do not correspond with the currently recognized taxonomy," the researchers reported in a paper being published in the Oct. 7 issue of the Proceedings of the Royal Society, Series B.

The findings, which need to be confirmed, could have implications for work aimed at protecting the elephants, which are threatened with extinction.

Hungarian researchers have determined what it takes to start a "wave" among sports fans.

Tamas Vicsek of the University of Budapest in Hungary and two colleagues used mathematical models developed to describe activity by things such as heart tissue to analyze videotapes of 14 waves at soccer stadiums holding more than 50,000 people.

A wave starts when at least 25 to 35 people stand up simultaneously "and subsequently expands through the entire crowd as it acquires a stable, near-linear shape," the researchers wrote in the Sept. 12 Nature.

Waves usually have a width of about 15 seats, roll in a clockwise direction and typically move at a speed of about 20 seats per second, the researchers found.

"Our approach may have implications for crowd control. For example, in violent street incidents associated with demonstrations or sporting events, it is essential to understand the conditions under which small groups can gain control of the crowd, and how rapidly and in what form this perturbation of transition in behavior could spread," they wrote.

The composition of some coins used for Europe's new currency, the Euro, apparently causes some people to have allergic reactions.

After hearing reports of allergic reactions from handling Euros, Frank Nestle of the University of Zurich and colleagues decided to study the coins. The researchers coated coins in artificial sweat and found they released 240 to 320 times the amount of nickel permitted under European Union regulations -- and more than pure nickel itself.

The reason appears to be that the 1-Euro and 2-Euro coins are made up of two metals. The 1-Euro coin consists of an outside ring of copper, zinc and nickel while the core "pill" is made of copper and nickel. The 2-Euro coin is made of a copper-nickel ring and a nickel pill. That encourages corrosion as metal ions flow from one alloy to the other.

"Further investigation is warranted not only into the epidemiological implications of such high-nickel releasing coins but also into the factors that promote nickel release, such as the crevice between the pill and the ring -- a potential corrosion site," the researchers wrote in the Sept. 12 Nature.

The word "like," which has been made famous -- or perhaps infamous -- by Southern California "Valley Girls," may finally be getting some respect.

"Like" has long been dismissed as a "discourse particle" -- a place-holder a speaker uses to fill time while searching for the right words. New research, however, indicates strategic use of "like" may imbue sentences with additional meaning.

Muffy E.A. Siegel, a linguist at Temple University in Philadelphia, decided to study the use of "like" further. She asked her 15-year-old daughter to record 23 suburban Philadelphia high school students as they answered the question, "What is an individual?"

After studying the tapes, Siegel concluded that the use of the word has evolved and now can play many different roles in spoken language. Its inclusion can change the meaning of a sentence. For example, "like" can be used as a way of hedging what is being said: "He has, like, six sisters." It can also be used to make clear that what is about to be said is an exaggeration. For example: "He's like 100 feet tall."

"The existence of an expression like like, a discourse particle that interacts with basic semantic interpretation, suggests strongly the need for a reexamination of the interactions of the components of grammar in linguistic theory," Siegel wrote in the Journal of Semantics.

-- Compiled from reports by Rob Stein