Magazine

A Cotton Candy Solution to Plant-Eating Bugs


Farmers may one day fight crop-munching insects with a polymer that sprays on like cotton candy. Unlike pesticides, this silky web of plastic doesn't poison the bugs or the environment. The fuzzy barrier just makes it harder for the creepy crawlies to get at vulnerable plants.

The idea occurred to Michael P. Hoffmann, a Cornell University entomology professor, while he was searching for nontoxic pest controls to which bugs would not become immune. Four years later, Hoffmann and his team settled on a recipe made of ethylene vinyl acetate, similar to the white goo in hot-glue guns, that can be sprayed harmlessly onto plant stalks. The cottony web has already proved effective against fly maggots--ravenous pests that destroy millions of dollars' worth of onion and cabbage plants each year.

Hoffmann's fuzz isn't yet ready for large-scale use. His team is still tinkering with the recipe, adding repellents such as capsaicin from hot peppers to make the web more obnoxious to bugs. And while the polymer currently must be removed by hand, the process will ultimately have to be automated.

Even so, with the Environmental Protection Agency phasing out more pesticides, there's a growing need for green options, says Hoffmann. He has patented the process and is talking with potential partners. The virus that causes AIDS mutates fast enough to develop resistance against drugs designed to fight it. Yet at the Ninth Conference on Retroviruses & Opportunistic Infections, held in Seattle in late February, scientists reported progress on new medicines and vaccines that may help keep HIV in check.

Some of the emerging drugs fight the virus using the same tactics as existing medicines. Bristol-Myers Squibb and Tibotec-Virco have drug compounds that attack the enzyme that HIV uses to copy its genes. Both drugs reduce virus levels in people infected with strains resistant to today's drugs.

Other medicines are opening new fronts against HIV. In order for the virus to get into cells, it must attach to two receptors on the surface of cells, dubbed CD4 and CCR5. Bristol-Myers scientists have developed a small molecule that sticks to the outside of the virus, preventing it from binding to CD4. The drug inhibits infection in animals. "It is a very important development," says Dr. David Ho, director of the Aaron Diamond AIDS Research Center in New York. Even further along is a drug from Schering-Plough that blocks the attachment of HIV to CCR5. Studies show that it lowers viral loads in patients.

Drug companies have also been trying to attack an HIV enzyme called integrase that enables the virus to insert its own genes into human cells. Scientists at Shionogi in Osaka, Japan, reported on a candidate that strongly inhibits HIV in the test tube.

All drugs have side-effects, though, so the best way to fight AIDS may be with vaccines. Merck scientists presented the first data from human trials of a promising approach.

Merck's team uses two vaccines. One is a piece of DNA which contains a gene from HIV. The other employs a modified cold virus to carry the same gene. When injected into the body, each vaccine prompts cells to make the viral protein. The hope is that the protein will stimulate the immune system to attack cells infected by the virus. In monkeys, the vaccine doesn't prevent infection, but it does enable the animals to keep HIV under control.

Does it also work in people? So far, Merck researchers have immunized scores of volunteers. Depending on the dose and vaccine type, the immune systems of 20% to 60% of people responded. "We have to stay cautious, but we are very encouraged by these results," says John Shiver, director of vaccine research at Merck. Rural businesses and others lacking access to broadband networks such as cable or DSL will soon have a new way to gain high-speed access to the Internet, using plain old copper phone lines. Artera Group International in Westport, Conn., is developing a system that it claims can increase the flow of data over existing telecom "pipes."

The acceleration can be impressive. Over one phone line, the Artera Turbo can deliver a fivefold increase, up to 250 kilobits per second (kbps) via a standard 56-kbps dial-up modem. In offices with two or more modems and phone lines, the system can compete with DSL modem upload speeds, which typically range from 400 to 600 kbps. Existing broadband connections, such as cable and DSL modems, get a boost, too.

The Turbo relies on six patent-pending technologies, so how-it-works details are skimpy. But John Lash, a vice-president of NCT Group, Artera's corporate parent, says the secret is swapping some PC power for bandwidth through a mix of caching, compression, optimization, and other techniques. One trick slashes the latency, or delay, between packets of digital data by 80%.

After testing Artera's setup, information specialist GTSI plans to offer the service to its government and university customers. "It's amazing technology," says GTSI technologist Mark Thoreson. As the service rolls out this spring, fees are expected to start at $175 a month for a three-user office, with service for homes and travelers coming later at $10 or $20 a month.


Tim Cook's Reboot
LIMITED-TIME OFFER SUBSCRIBE NOW
 
blog comments powered by Disqus