One reason airliners use jet engines to propel themselves is that if they flapped their wings as a bird does, it could rock the passengers so much that they`d spill their drinks.
There are probably other reasons as well, but there is nothing in fundamental physics to prevent building airplanes that imitate birds to gain flight.
Two researchers, Jeremy Harris of the Battelle Institute in Columbus, Ohio, and James DeLaurier of the University of Toronto, have proven that by building a wing-flapping model and flying it. DeLaurier describes the 20-year effort that led to success as ”an avocation funded primarily by ourselves.”
The machine, which they call an ornithopter, weighs almost 10 pounds and has a wing span of nearly 10 feet. The craft stayed aloft for 1 minute 46 seconds on its first flight and 2 minutes 46 seconds on its second flight. It is limited to short flights because the fuel tank carries only 4 ounces of fuel to power its engine.
PROSTATE CANCER LINKED TO HEREDITY Prostate cancer appears to be inherited in some families, according to Johns Hopkins University School of Medicine researchers, who hope the new findings will uncover the defective gene responsible for the cancer.
A study of nearly 700 families found that prostate cancer occurred in a classical Mendelian pattern of inheritance in some families, Dr. Patrick C. Walsh reported in the Proceedings of the National Academy of Sciences. In these families 88 percent of the men who reach age 85 have prostate cancer, compared with a 5 percent prostate cancer rate in men of the same age who do not have the cancer gene, he said.
Finding the gene could lead to better ways to diagnose and treat the more common form of prostate cancer, Walsh said.
22-YEAR STUDY LINKS TV, VIOLENT BEHAVIOR Youngsters who watch excessive amounts of television violence tend to engage in more violent behavior and criminal activity as adults, a University of Illinois at Chicago study has found.
A 22-year study of 875 8-year-olds from a semi-rural New York county showed that by age 30 those who had watched more television violence at 8 were convicted of more serious crimes, said psychologist Leonard Eron.
They were also more aggressive under the influence of alcohol and punished their children more harshly, said Eron, who heads the American Psychological Association`s commission on Violence and Youth.
The new findings support earlier results, which showed that boys who were low in aggressive behavior at 8 but who watched more television violence became more aggressive at 19 than boys who originally were highly aggressive but watched less television violence. Eron reported the findings March 31 before the U.S. Senate Committee on Governmental Affairs. A more recent three- year study of suburban Chicago youths showed the same effect of TV violence, he said.
”Television violence affects youngsters of all ages, of both genders, at all socio-economic levels and all levels of intelligence, and the effect is not limited to children who are already disposed to being aggressive and is not restricted to this country,” he said.
CITRIC `CIGARETTE` MAY HELP SMOKERS QUIT Puffing on a ”cigarette” that contains nothing but citric acid from lemons may help smokers give up the habit. The smoke substitute provides a strong, scratchy feeling that is very similar to that of cigarette smoke, said Jed E. Rose of Duke University Medical Center`s division of biological psychology.
Combined with the nicotine patch, which Rose helped develop, the smoke substitute may give smokers the feeling of smoke that they find enjoyable, he said. Trials to determine if the two can encourage more smokers to kick the habit are under way.
DOCTORS TURN NOW TO FECAL INCONTINENCE Urinary incontinence is finally being recognized as a common problem that can be treated. Now researchers want to give fecal incontinence equal billing. Writing in the New England Journal of Medicine, Dr. Robert D. Madoff of the University of Minnesota said that fecal incontinence is underreported and underdiagnosed.
Studies in England suggest that it may affect 4.2 men and 1.7 women for each 1,000 people ages 15 through 64, and 10.9 men and 13.3 women for each 1,000 people 65 and older.
Treatment includes diet modification, medical therapy, biofeedback and surgery, Madoff said. ”Because the problem is often correctable, failure to diagnose it causes unnecessary dismay, a loss of independence, and needless expense.”
COUGH-AND-COLD MEDICINE NOT FOR CHILDREN Combination cough and cold medications have not been proven to be effective in children though they are commonly prescribed, and they are involved with an increasing number of health problems, according to a report in Pediatrics, a journal of the American Academy of Pediatrics.
In 1990 one out of every 15 calls to the Maryland Poison Center concerned these medications, often toxic overdoses, said Dr. Anne Gadomski of the University of Maryland. Nationwide, in 1987, there were 76,566 calls to poison control centers about these medications, she said.
”Given the lack of data on efficacy, and the increasing reports of toxicity in infants and children, rational therapeutics should not include combination cough and cold medications treatment of upper respiratory tract infections in infants,” she said.
STRESS MAKES WOMEN EAT MORE, MEN LESS Stress makes women eat more and men eat less. At least that`s the conclusion of a study of 26 healthy young males and 28 females conducted by psychologist Neil Grunberg of the Uniformed Services University and behavioral scientist Richard Straub of the University of Michigan at Dearborn.
Shown stressful films of accidents, women ate nearly twice as much sweet food and more salty and bland snacks as they did when shown soothing films, the researchers reported in Health and Psychology, a publication of the American Psychological Association.
Men, on the other hand, cut their food consumption by more than half when watching the stressful film, they said.
Although it is difficult to make generalizations about eating under stress, sex, food types and restraint appear to be factors, said Grunberg and Straub.
WOMEN WITH AIDS TEND TO BE IGNORED Although the number of women with AIDS is steadily increasing, they tend to be ignored in terms of diagnosis and new drug treatments, said Dr. Kay Bauman, director of the University of Arizona College of Medicine`s AIDS Education Projects.
Women with AIDS die more quickly than men, primarily because they are usually not diagnosed as early with the immunity-destroying infection, she said. Only 20 percent of women with AIDS survive for three years, she added.
Furthermore, few AIDS drug trials have involved women, so there is little information on how these powerful medications affect them, she said.
INFANTS SUFFER SEIZURES FROM TOO MUCH WATER As times get tougher, an increasing number of mothers on welfare are giving their infants water instead of formula or milk, leading to a condition called oral water intoxication, according to a report in American Medical News.
The publication cites an article by Dr. James Keating of Washington University and St. Louis Children`s Hospital in which he said the hospital treated 31 infants who suffered seizures after being given large amounts of water.
”This didn`t exist in our hospital before 1982,” said Keating, who reported his findings in the American Journal of Diseases of Children. ”At first we had two to three cases a year. Now it`s up to 8 to 12 cases a year.” AGE NO HINDRANCE FOR PUBLIC-SAFETY OFFICERS When Congress banned the use of mandatory retirement ages in 1986, it excluded public-safety officers (police and corrections officers, and firefighters) on the grounds that they would be too old to perform their duties.
But a $1 million, 16-month study by Frank J. Landy, director of the Center for Applied Behavioral Sciences at Pennsylvania State University, found that older public-safety officers often performed better than younger ones.
”In fact, public safety might actually be enhanced by virtue of allowing the experience of public-safety officers to accrue,” Landy reported at the annual meeting of the American Psychological Association.
Landy reviewed more than 2,000 studies on aging and performance and surveyed 182 police departments, 165 fire departments and 102 correctional facilities around the U.S. Age is not a good predictor of who is capable of protecting the public, but physical fitness and mental abilities are, he said.
