In Brief

In Brief

March 10, 2006

Epidemiology

Immunizations cut measles deaths

A worldwide immunization drive cut measles deaths by almost 50 percent between 1999 and 2004, the World Health Organization and the United Nations Children's Fund announced today.

Global deaths attributed to measles fell from 871,000 to 454,000 over the five-year period. The largest reduction, 60 percent, occurred in sub-Saharan Africa, the region with the highest incidence of the disease.

SUN STAFF

Astronomy

Next sunspot cycle to be stronger

Scientists say the next sunspot cycle - the season of solar storms that can disrupt satellites and global positioning systems - will begin late next year and will be up to 50 percent stronger than the last one.

Scientists at the National Center for Atmospheric Research also say the next 11-year cycle will be a year late and reach its peak about 2012. Researchers used a newly designed computer model and observations from NASA's Solar and Heliospheric Observatory, which tracks sound waves in the sun's interior.

Solar storms are caused by eruptions of magnetic energy near the surface of the sun that snap and release tremendous amounts of radiation that can reach the Earth in minutes. They can occur at any time, but generally follow 11-year cycles of peak storm activity and quiet periods. The most recent cycle was relatively weak and has been waning since it peaked in 2001.

The Earth's magnetic field shields us from most of the radiation. But it can cause surges on electrical power grids, throw satellites out of orbit and threaten satellite-controlled radio communications, global positioning systems and navigational instruments. The storms also increase radiation hazards to astronauts and those in commercial airliners flying polar routes.

Dennis O'Brien

Cardiology

Extra coffee ups heart attack risk

An extra cup of coffee increased the risk of a first heart attack in people with a common defect in the gene responsible for breaking down caffeine, researchers reported this week. But people with a normal gene face no added risk.

The study compared 2,000 Costa Ricans who had suffered a first heart attack with an equal number of healthy people. Participants were asked about coffee consumption and tested for a mutation in the CYP1A2 gene, which processes caffeine. Up to half the population in urban areas has the defect, researchers said.

People with the genetic defect take up to four times as long to process caffeine, scientists at the University of Toronto said. Caffeine constricts the blood vessels, which can trigger higher blood pressure.

A single cup of coffee daily did not increase the heart attack risk in people with the genetic defect. But those who drank two to three cups of coffee daily faced a 36 percent increased risk of a first heart attack. Those consuming four or more cups of coffee had a 64 percent higher risk

The report in the Journal of the American Medical Association helped explain why earlier studies on the health effects of coffee produced conflicting results, researchers said. None of the other studies looked at genetic differences among coffee drinkers.

LOS ANGELES TIMES

Entomology

Cockroaches can be conditioned

Japanese scientists have confirmed conditioned reflexes in cockroaches, just like Pavlov's drooling dogs, according to a report in the British Journal of Experimental Biology. This is the first confirmation of the conditioned reflex in a creature other than a mammal.

When researchers at Tohoku University in Sendai sprayed peppermint odor on 3-centimeter-long American cockroaches, the nerve cells that control salivation were not activated in response. But after they conditioned the cockroaches by spraying the odor five times just before feeding the insects a sugar solution, the peppermint did trigger the insects' nervous system. This effect persisted a day later, they said.

The conditioned reflex was confirmed by Russian physiologist Ivan Pavlov a century ago in an experiment on dogs. When dogs come across food, they begin drooling. The experiment showed that after the dogs had been conditioned to hear a bell just before they were fed, they drooled when they heard a bell, even if no food was present.

KNIGHT RIDDER/TRIBUNE

Discoveries

Furry lobster found in South Pacific

A team of American-led divers has discovered a new crustacean in the South Pacific that resembles a lobster and is covered with what looks like silky, blond fur, French researchers said this week.

The animal, which they named Kiwa hirsuta, was so distinct from other species that they created a new family and genus for it. The divers found the animal in waters 7,540 feet deep at a site 900 miles south of Easter Island last year, according to Michel Segonzac of the French Institute for Sea Exploration.

The new crustacean is described in the Journal of the National Museum of Natural History in Paris.

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