UPI NewsTrack Health and Science News

Glycine found in samples of a comet

PASADENA, Calif., Aug. 17 (UPI) -- U.S. space agency scientists say they've found glycine, a basic building block of life, in samples of comet Wild 2 returned by NASA's Stardust spacecraft.

"Glycine is an amino acid used by living organisms to make proteins, and this is the first time an amino acid has been found in a comet," said Jamie Elsila of NASA's Goddard Space Flight Center in Greenbelt, Md. "Our discovery supports the theory that some of life's ingredients formed in space and were delivered to Earth long ago by meteorite and comet impacts."

Elsila is the lead author of a paper on the research that's been accepted for publication in the journal Meteoritics and Planetary Science.

"The discovery of glycine in a comet supports the idea that the fundamental building blocks of life are prevalent in space, and strengthens the argument that life in the universe may be common rather than rare," said Carl Pilcher, director of the NASA Astrobiology Institute, which co-funded the research.

The research was presented Sunday during a meeting of the American Chemical Society in Washington.

Children reporting sex at 12

AMES, Iowa, Aug. 17 (UPI) -- A study of 1,000 low-income families in three U.S. cities found one in four children and teens between the ages of 11-16 reported having sex, researchers said.

Brenda Lohman of Iowa State University said the study that involved children and teens in Boston, Chicago and San Antonio found the first sexual intercourse experience occurred at the average age of 12.77.

"So if 12 years was the average age here, that meant that some kids were starting at 10 or younger," Lohman said in a statement. "A handful of kids reported having sex as early as age 8 or 9. We know from our follow-up interviews that one boy who reported having sexual intercourse for the first time at age 9 had fathered four children by the time he was 18."

The researchers first collected interview data in 1999 on youth at ages 10-14, again in 2001 and once again 2006.

The study, posted online in the Children and Youth Services Review and scheduled to be published in an upcoming issue of the journal, found boys reported their first sexual intercourse at an age averaging 12.48, and girls at age 13.16. Boys also had nearly 10 percent higher frequency of intercourse than girls.

NASA demonstrates inflatable heat shield

WALLOPS ISLAND, Va., Aug. 17 (UPI) -- The U.S. space agency has demonstrated how a spacecraft can use an inflatable heat shield to slow and protect itself during re-entry to Earth's atmosphere.

The Inflatable Re-entry Vehicle Experiment was launched on a small sounding rocket from NASA's Wallops Island Flight Facility in Virginia at 8:52 a.m. EDT Monday. The 10-foot diameter heat shield, made of several layers of silicone-coated industrial fabric, inflated with nitrogen to a mushroom shape in space several minutes after liftoff.

"Our inflation system, which is essentially a glorified scuba tank, worked flawlessly and so did the flexible aeroshell," said Neil Cheatwood, the experiment's principal investigator. "We're really excited today because this is the first time anyone has successfully flown an inflatable re-entry vehicle."

The key focus of the research came about 6 1/2 minutes into the flight, at an altitude of about 50 miles, when the aeroshell re-entered Earth's atmosphere and experienced its peak heating and pressure measurements for a period of about 30 seconds.

The technology demonstrator splashed down and sank in the Atlantic Ocean about 90 miles east of Virginia's Wallops Island.

"This was a small-scale demonstrator," Mary Beth Wusk, the experiment's project manager said. "Now that we've proven the concept, we'd like to build more advanced aeroshells capable of handling higher heat rates."

Blood parasite genetic linkage map created

COLLEGE STATION, Texas, Aug. 17 (UPI) -- A U.S. scientist says he has completed the first genetic linkage map for Schistosoma mansoni -- a blood parasite linked with schistosomiasis.

S. mansoni is a complex and aggressive pathogen affecting more than 90 million people in Africa, the Middle East and South America, Texas A&M University Assistant Professor Charles Criscione said. Schistosomiasis is a debilitating, chronic disease that can damage internal organs and impair growth in children.

Criscione and his team of researchers said their map will be useful in piecing together the S. mansoni genome sequence, which is in 19,000 fragments. And, because it is the first genetic map for a platyhelminth (flatworm) species, it will also be a platform for other flatworm genomics, he said.

"The linkage map we constructed will help assemble the genome and will serve as a useful genetic tool to help find genes that control important traits, such as drug resistance, virulence and host specificity," Criscione said. "It has been shown that the parasite can vary for many of these traits. Knowledge of genomic regions that affect these traits will help identify new targets for drugs and vaccines and may help identify parasite genes involved in pathology."

The study appears in the online version of the journal Genome Biology.