Sci-tech news (12)
hyt...@my-dejanews.com
* Batteries not included
New Scientist, 3/10/98
Last month's crash of Swissair Flight 111 off Halifax, Nova Scotia, has
revealed a disturbing flaw in the rules governing black box flight
recorders. Because of a loss of power, the final minutes of voice and
flight data are missing. Safety experts are calling for changes to ensure
that recorders are backed up by battery power.
The crash left 229 people dead, yet without the missing data the tragedy
may never be fully explained. Investigators with the Transportation Safety
Board of Canada (TSBC) have found that the aircraft's cockpit voice
recorder and flight data recorder stopped working six minutes before the
aircraft disappeared from radar screens.
TSBC spokesman Dana Doiron says both recorders were powered by the third of
the aircraft's three main power lines. The MD-11 airliner that crashed has
three engines, and each line gets power from a different engine. Prior to
the crash, the aircrew had reported smoke in the cabin. If they followed
standard safety procedures to identify the source of an electrical fire,
they may have switched off the number three line first in an attempt to
isolate the problem.
Investigators are still piecing together what really happened. If the
recorders had been backed up by battery power, their job might have been
easier. What is the point of making black boxes virtually indestructible,
ask some industry sources, if they can be switched off by pilots or knocked
out if one of an airliner's power lines fails?
"You need to gather data right to the end, says Denis Chagnon, spokesman
for the industry's global safety regulator, the Montreal-based
International Civil Aviation Organization. Chagnon expects the final report
on the crash to recommend the introduction of mechanisms to keep black
boxes working even if power fails.
An airliner's voice recorder tapes all cockpit noise, including radio
conversations, pilots' voices and engine noise. It records on a 30-minute
loop, so that in the event of a crash, investigators can listen to the
aircraft's final minutes. The flight data recorder, taping on a 25-hour
loop, records key parameters such as altitude, airspeed and flap position.
Currently, the only part of the recorders that have battery power are their
underwater locator beacons, which emit an acoustic signal for 35 days.
John Thom, a spokesman for Boeing in Seattle, which makes the MD-11, says
that providing battery power to existing black box recorders may be
counterproductive--because the tape is a loop, the data would be
overwritten if the devices weren't quickly recovered. But Albert Reitan, a
specialist in voice recorder analysis at the US National Transportation
Safety Board in Washington DC, says this problem could be solved by adding
a "g-switch" between the battery and the recorder that would sense the
force of the crash and cut out.
So why haven't such devices already been made mandatory? Les Dorr, a
spokesman for the US Federal Aviation Administration in Washington DC, says
that one reason his organisation hasn't acted is that, in the event of a
total power failure, the systems that feed information into the flight data
recorder would also shut down. "The data recorder would function, but there
would be nothing on it," he says.
But Reitan notes that five key instruments in modern aircraft, including
the airspeed indicator and the altimeter, are low-powered liquid crystal
display devices that themselves have battery back-up. So there would still
be some key data to record. "In any investigation, the more information you
have the better off you are," he concludes.
* Starquake turned night into day
New Scientist, 3/10/98
For five minutes on 27 August, the Earth's upper atmosphere was electrified
by a burst of gamma rays from a distant star. The event has refined
astronomers' views of a strange class of stars called magnetars.
The source of the gamma rays was a star called SGR1900+14, which has
previously emitted similar but smaller bursts. Astronomers now believe that
such "soft gamma-ray repeaters" are young neutron stars with intense
magnetic fields. According to theory, the motion of the magnetic field
through the neutron star's iron crust heats it to millions of degrees until
it cracks apart in the stellar equivalent of an earthquake, releasing gamma
rays ("Starquake", New Scientist, 15 August, p 26).
The Earth's upper atmosphere is ionised by solar radiation during the day,
but becomes de-ionised at night. Although SGR1900+14 lies 20 000 light
years away, its burst ionised the atmosphere of the Earth's dark side down
to an altitude of 60 kilometres. "It looked just like daytime," says Umran
Inan, an astronomer at Stanford University in California.
The gamma rays saturated the detectors of two spacecraft and triggered an
automatic shut-off of a third. Kevin Hurley of the University of California
at Berkeley estimates that the starquake released as much energy in 5
minutes as the Sun emits in 300 years. Fluctuations in the intensity of the
gamma rays fit well with models of the behaviour of magnetars, he adds.
* Nauseating business
New Scientist, 3/10/98
Short-lived chemicals formed when ozone reacts with traces of organic
pollutants could help explain the mystery of "sick building syndrome",
Danish researchers suggest.
For many years, experts in occupational health have puzzled over symptoms
reported by office workers, including headache, nausea, fatigue and
irritation of the eyes, nose, throat and skin. In some cases, the culprit
is clear: poor ventilation, tobacco smoke or airborne bacteria. But in
others, no suspect has emerged.
Some scientists suspect that volatile organic compounds are to blame. VOCs
come from many sources, including wood, carpets, perfumes and even human
breath. But their concentrations in the air we breathe are usually much
lower than those shown to affect health. Now Peder Wolkoff and his
colleagues at the National Institute of Occupational Health in Copenhagen
have found that, in combination with ozone, one common VOC can produce eye
and airway irritation at concentrations much lower than would be needed if
it were in isolation. Ozone can enter buildings in photochemical smog from
outside and is also produced by equipment such as photocopiers.
Wolkoff's team measured the responses of 12 mice to a mixture of ozone and
alpha-pinene, which is given off by wood and pine-scented products. After
30 minutes, the animals' breathing rate decreased on average by 30 per
cent, indicating airway irritation. The experimental concentrations, when
adjusted to account for the fact that mice are less sensitive to air
pollutants than people, are similar to those that might be experienced in
an office building, Wolkoff says.
When mice breathed air containing ozone and alpha-pinene separately, or the
end products formed after ozone and alpha-pinene have been left to react,
their response was minimal, the researchers report in a paper due to appear
in the journal Atmospheric Environment.
Wolkoff believes the culprits must be short-lived compounds formed by the
initial reaction between the VOC and ozone. He doesn't yet know what these
irritants are. But they could be reactive radicals with lifetimes too
fleeting to detect with current techniques. That's plausible, agrees
Charles Wechsler, an indoor air expert at Bell Communications Research in
Red Bank, New Jersey: "I'm afraid there's a lot that we're missing right
now."
Wolkoff's work was funded by the Center for Indoor Air Research in
Baltimore, a body set up by the tobacco industry. Industry documents have
revealed that it has funded research into indoor pollution in an attempt to
divert attention from the dangers of passive smoking (This Week, 2 May, p
22, and 16 May, p 4). But Wolkoff says that his results won't provide much
comfort to tobacco firms. "There are a whole group of VOCs that will react
in the same way," he says. They include a widely used lemon scent,
chemicals from carpets and linoleum--and VOCs from tobacco smoke.
Other experts hope Wolkoff's research will provoke further experiments on
interactions between different airborne pollutants. "Our understanding of
the health effects of mixtures is not as good as it ought to be," says
Leslie Sparks, a chemical engineer with the US Environmental Protection
Agency in Washington DC.
* Old before their time
By Barry Fox electronics companies are on the point of launching a new
generation of digital TV receivers which will use hard-disc drives to
record programmes. The news will dismay those who have invested in digital
receivers that will soon be superseded, especially in Britain, where
satellite digital broadcasting is being launched this week.
Digital TV experts last week revealed a specification for a set-top
receiver dubbed "TV Anytime" that will learn what a viewer's favourite
programmes are and automatically record them. The box can also be set to
record particular genres, such as soaps, news or sport. Jean François
Jezequel of French pay TV service Canal Plus, which has run digital TV for
two years on satellite and cable, says his company "is already
experimenting with the technology".
In the US, the California companies TeleWorld of Sunnyvale and Replay
Networks of Palo Alto, along with the Duck Corporation of New York, are
promising the first $500 "storage receivers" this winter. They will record
around 7 hours of programmes.
Meanwhile, in Britain, the Independent Television Commission has failed to
ensure that the first digital pay TV receivers can be converted between
terrestrial and satellite reception. European competition law allows the
ITC to insist that digital sets have a "common interface" socket--this can
connect to an add-on "sidecar" module that allows reception of rival
services. But the ITC is only now talking to Oftel, the telecoms watchdog,
about some kind of regulation to protect consumers. Digital sets are
already going on sale without sidecar units, so the first digital viewers
risk being trapped with whichever pay service they try first.
* A taste for naked fruit
New Scientist, 3/10/98
Melbourne apple slices that taste like pears, and bananas that taste of
pineapples can now be made with the help of a food coating developed by
Food Science Australia (FSA). The peeled fruit will be coated with an
edible film so that it stays fresh and does not turn brown.
The first fruit with the coating, Snack Apple made by Westernport
Coolstores, went on sale in Australia last week. Four varieties of apple
are available, each flavoured with a hint of pineapple.
When fruit is cut open, it goes brown due to oxidation mediated by the
enzyme polyphenoloxidase. The new coating, made from a combination of
vegetable gums such as pectin and carragenans, and antioxidants such as
vitamin C, prevents oxidation by binding to the enzyme and halting the
browning reaction.
"What we set out to do was to increase the consumption of fresh fruits,"
says Vic Reyes from FSA in Melbourne. He says slices of the ready-peeled
fruit will appeal to children because they often find a whole apple or
orange too large to eat--or too hard to peel. But which fruit gets to taste
like another will depend on consumer demand, says Reyes.
Hands today, faces tomorrow
By David Concar the controversial hand transplant operation that took place
in a French hospital last week raises the prospect of something even more
macabre--a human face transplant.
While doctors in Lyon continue to closely monitor Clint Hallam and his hand
for signs of rejection, a rival American team is gearing up for many
similar operations. "We'll do at least 10 of these in the coming year,"
says John Barker, a plastic surgeon at the University of Louisville in
Kentucky.
Whereas most transplants involve grafting only single organs or tissues, a
hand transplant requires skin, muscles, nerves and bone all to be grafted
at once. This makes hand transplants a good way of testing drug
combinations that might stop the body rejecting multiple tissue grafts,
especially ones involving skin, the most immunogenic tissue.
Ultimately, Barker predicts that the greatest demand for such transplants
will come from patients who lose their faces in a fire, or through disease,
shotgun wounds or dog attacks. Surgeons currently rebuild faces using flaps
of skin and muscle taken from elsewhere on the patient's body. Barker says
they could get a much better-looking result by transplanting the facial
skin, muscles, nerves and lips of a dead donor the same age.
However, John Williams, vice-president of the Royal College of Surgeons in
London, thinks that few patients will have injuries severe enough to make
such operations worthwhile.
* Delicate operations
New Scientist, 3/10/98
Washington DC - WHat can dock the space shuttle and spot a brain tumour?
No, it's not an astronaut's personal physician--it's a neural networking
computer algorithm designed by engineers at NASA. The system has become so
adept at analysing the large amount of data needed to dock a spacecraft
that it is also being harnessed by doctors to analyse tumours.
Recognising patterns is neural networks' forte (see New Scientist, print
edition, "Gas on the brain", p 36). They do pretty well with a small number
of parameters, but go beyond 10 or so inputs and the neural nets get
confused and become hard to train.
For humans, by contrast, this sort of task comes quite naturally. For
example, a surgeon taking a look at a chunk of tissue might subconsciously
analyse its colour, consistency and shape, and conclude that it's a
malignant growth. All this can happen in a split second, without the
surgeon being aware of the process.
Now a neural computer that handles many pieces of data at once has been
designed by a team led by Robert Mah, an engineer at NASA's Ames Research
Center at Moffett Field, California. "It's a neural net where lots of
parameters are analysed in real time," explains Mah. "It's looking at 25 or
more; it's pretty hard to do that."
Mah's neural net can take the data from a surgical probe--such as speed of
blood flow, fluid pressure or optical reflectance--and discriminate between
cancerous and healthy cells. "You'll get real-time feedback about what
tissue is at the tip of the probe during a biopsy," says Mah. "The goal,
initially, for brain applications, is to avoid hitting blood vessels."
Clinical trials are scheduled to start soon at Stanford University.
The neural net can also do things that are more obviously useful to
NASA--like docking the space shuttle with the International Space Station.
Instead of taking data from a biopsy probe, the neural network is connected
to the space shuttle's navigational system. In simulations, and after a few
test manoeuvres to learn the weight characteristics of the spacecraft, the
neural net outperformed NASA's highly trained shuttle astronauts. Coming
after the near-disaster aboard Mir due to a docking mishap with a cargo
ship, more reliable docking systems would do wonders for NASA's confidence.
The only risk is bruising the crew members' egos. "Astronauts want to be in
control," says Mah. Another application for the network might be in helping
to learn the way a spacecraft rotates in space while firing its impulse
jets. The system would then precisely slow the craft's rotation by burning
the jets for the correct period.
But NASA's work remains promising for doctors and their patients. "There's
no question that what he's doing is potentially very important," says Faina
Shtern, the assistant director for research and technological affairs with
the US Department of Health and Human Services. She hopes the neural net
will be able to find out whether tumours and lesions are malignant without
causing the patient unnecessary discomfort.
* X-ray vision
New Scientist, 3/10/98
BY MARCUS CHOWN Pulsars that only emit X-rays, once considered "anomalous",
now officially outnumber those that emit radio waves. This is leading
astronomers to rethink their ideas about what happens after a typical dying
star explodes as a supernova.
A supernova explosion occurs when a star runs out of nuclear fuel and
shrinks catastrophically under its own gravity. The result is a super-dense
neutron star about the size of Mount Everest. Current theories of how these
stars behave predict that they should all act as radio pulsars, sweeping a
narrow beam of radio waves around the sky like a lighthouse a hundred times
a second. So why didn't radio searches find more pulsars in supernova
remnants?
"The trouble is that hardly more than 1 per cent of the 300-odd known young
supernova remnants contain associated radio pulsars," says Eric Gotthelf of
NASA's Goddard Space Flight Center near Washington DC. But now the reason
they went missing is clear, Gotthelf says. Astronomers were looking in the
wrong part of the electromagnetic spectrum.
In the past few years, astronomers using the Japanese-American ASCA
satellite have found three "point-like" objects in the centres of supernova
remnants which are emitting pulses of X-rays. Now Gotthelf says that he has
just picked out three more of these "anomalous X-ray pulsars" (AXPs) in
X-ray sources observed by the satellite. Add these three to the list and
anomalous pulsars in supernovae remnants will outnumber the four known
radio pulsars associated with supernovae remnants for the first time, he
reports in a paper to appear in the journal Memorie della Societá
Astronomica Italiana.
These findings will mean that radio pulsars are the exception rather than
the norm. "This is a complete reversal of our thinking," says Gotthelf.
David Hough of Trinity University in San Antonio, Texas, confirms that
these new findings mean that "the book on how pulsars are born in
supernovae may have to be rewritten".
The X-rays coming from AXPs are produced by matter channelled by the star's
magnetic field lines and heated to enormous temperatures. AXPs spin a
thousand times slower than radio pulsars and are slowing down rapidly. This
is puzzling, because when a star shrinks to the relatively tiny size of a
neutron star it should automatically spin very fast. According to Gotthelf,
the most likely explanation is that AXPs are indeed born spinning fast, but
slow down quickly because they have a super-strong magnetic field, hundreds
of times stronger than in radio pulsars.
"Such a strong magnetic field would drag material around as the star spins,
sapping the star of rotational energy," says Gotthelf. A super-strong
magnetic field would also prevent the formation of the electrons needed to
produce radio waves. One possible explanation for the different magnetic
field strengths in radio pulsars and X-ray pulsars is that stars start out
with a natural variability in magnetic fields before they collapse.
At least two more sensitive X-ray satellites will be launched in the next
few years, and Gotthelf believes they will find many more radio-quiet
pulsars.
* Space attacks
New Scientist, 3/10/98
The leonid meteor storm that may light up the sky in Asia when it strikes
the Earth next month could pose a bigger threat to satellites than
astronomers had feared.
Every year, around mid-November, the Earth crosses the orbit of a comet
called Tempel-Tuttle and passes through debris the comet has shed. This
burns up in the upper atmosphere as a meteor shower. Every 32 to 33 years,
the Earth runs into an especially dense cloud of debris, turning the shower
into a storm. At the peak of the last storm, in 1966, the skies above North
America were lit up by 5000 meteors in just 20 minutes.
Astronomers are now bracing themselves for the next Leonid storm, predicted
to reach a peak around 17 November. Communications and other satellites
could be threatened by the bombardment--and both NASA and the Russian Space
Agency have postponed launches until the danger has passed.
No one knows just how bad the damage will be. For example, astronomers
can't predict with certainty exactly where the densest part of the debris
cloud is. Now Duncan Steel, an astronomer with Spaceguard Australia in
Adelaide, has thrown another variable into the equation. If his model of
the chemical composition of the Leonid meteors is correct, attempts to
observe the approaching meteors may detect only a few per cent of them.
Steel says that data gathered during the recent visits by comets Hale-Bopp
and Hyakutake reveal that the dust these comets gave off was rich in
volatile organic compounds. If the same is true of the cometary debris that
forms the Leonids, most of the meteors may be invisible. This is because if
they are made of highly volatile material, many will burn up at relatively
low temperatures--too low to leave behind glowing trails detectable from
the ground. Cool-burning meteors will also emit relatively few electrons,
and that will make them invisible to ground-based radars, which can only
spot electron-dense trails.
"If small meteoroids in storms are largely composed of organics, then none
of the data collected to date gives a realistic assessment of the hazard
level," says Steel, whose conclusions are published this week in the
journal Astronomy and Geophysics (vol 39, p 24).
Current estimates put the risk of a serious impact between a meteor and a
large satellite at about one in a thousand. Steel says his study suggests
that this "seriously underestimates" the hazard. "If I am right, the
economic loss caused by the Leonids may be immense," he says.
Other astronomers agree that the reliability of the storm predictions
depends crucially on the composition of the meteors. "Steel's paper is very
interesting--though whether it is actually correct is another matter," says
Iwan Williams of Queen Mary and Westfield College, London. "We may know
after the Leonids next month."
Steel's advice is not to rely too heavily on satellite communication and
navigation systems in the coming month. "I would not depend for my life on
the Global Positioning System being fully functional on 18 November," he
says.
* Radar on the storm
New Scientist, 3/10/98
Atmospheric scientists in the US rode out the arrival of Hurricane Georges
this week in two specially reinforced trucks. The vehicles are fitted with
mobile radar generators that probed the hurricane as it came ashore. Joshua
Wurman of the University of Oklahoma and his colleagues have previously
found streaks of wind with speeds up to 80 kilometres per hour higher than
the average for a hurricane. This may explain localised areas of intense
damage (This Week, 2 May, p 15).
* Virtual orifice
New Scientist, 3/10/98
Computer scientists at the University of Glasgow have constructed a virtual
rear end of a horse to help train veterinary students. Having sixty
untrained students subjecting a horse to an internal examination puts the
animal under great stress, and may even injure it. Instead, students can
now place a finger inside a force-feedback glove to feel a computed model
of a horse's ovaries. The system can simulate a much wider range of
abnormalities than students would usually experience. The device is part of
Glasgow's Revelation project, an initiative launched this week to use
virtual reality for teaching.
* Early birds
New Scientist, 3/10/98
Songbirds may be an offshoot of an early branch in bird evolution, rather
than perched at the top of the evolutionary tree.
Neurobiologist Jeffrey Woodbury of the University of Pittsburgh says that
birds can be divided into two groups according to the pattern of tissues in
their spinal cords (Proceedings of the Royal Society B, vol 265 p 1721).
Songbirds have the same tissue pattern as more primitive orders of birds,
suggesting that they are more closely related to these ancient lineages
than scientists previously thought. Evolutionary biologists have largely
ignored these traits in birds, says Woodbury.
* Earth's alter ego
New Scientist, 3/10/98
Astronomers have spotted two more new planets orbiting Sun-like stars, and
both are important firsts.
One planet is about as far from its parent star as the Earth is from the
Sun. Other recently discovered planets were either much closer or much more
distant. "We had been a little puzzled why we hadn't found any planets with
an orbital distance similar to the Earth," says Geoff Marcy of San
Francisco State University. The new planet, which has at least 1·2 times
the mass of Jupiter, orbits its star in 437 of our days. Its orbit is far
more eccentric than the Earth's, and would range between the orbits of
Venus and Mars in our Solar System.
The second planet is the closest ever found to a star, speeding around it
in only 3·1 of our days. At least half the mass of Jupiter, it is a mere
six million kilometres from its sun, giving it a torrid surface temperature
of more than 1100 °C. That's "hot enough to cook a chicken in a
millisecond", says Marcy.
* Male smokers affect kids’ fertility - Women who drink even a little coffee
less likely to conceive
MSNBC, 2/10/98
Consuming even small amounts of alcohol and caffeine can reduce a woman’s
fertility, report Baltimore researchers. And a second study shows that young
men who smoke may be affecting both their fertility and that of their
children.
TOGETHER, the studies re-emphasize the dangers of drinking, smoking and lots
of coffee, said Dr. Alan DeCherney, editor of the journal Fertility and
Sterility. Most worrisome, he said, is that “these studies showed the adverse
affects on fertility and the health of future generations.” In the
first study of 124 women trying to get pregnant, those who abstained from
alcohol and drank less than one cup of coffee per day were more than twice as
likely to conceive as those who did consume alcohol and had a cup of java a
day or more. Overall, there were 10.5 pregnancies per 100 menstrual
cycles in the alcohol- and coffee-drinking women, compared to 26.9
pregnancies per 100 menstrual cycles in the women who consumed no alcohol and
less than one cup of coffee per day. And the more a woman drank, the
less likely she was to conceive, the study showed. Caffeine
consumption did not affect fertility in and of itself, but enhanced the
negative effects of alcohol, said study author Rosemarie Hakim of at Johns
Hopkins School of Medicine. While further research should be
conducted on larger numbers of women, the work clearly points to the need for
abstaining from alcohol and caffeine consumption when trying to conceive,
Hakim said. Both studies appear in the October issue of the journal
Fertility and Sterility. MEN WHO SMOKE
The second study, conducted in the Czech Republic, looked at 10 18-year-old
men who had been smoking 20 cigarettes per day for at least two years and 15
nonsmokers with little exposure to secondhand smoke. Most of the smoking men
regularly consumed alcohol.
Participants answered a questionnaire and provided urine and sperm samples
for analysis. The sperm of smokers was more likely to have genetic
abnormalities than that of non-smokers, reported Andrew Wyrobek of the
Lawrence Livermore National Laboratory in Livermore, Calif. The
genetic sperm defects could affect not only the smoker’s fertility, but also
could be passed on to any subsequent children of the smoker, Wyrobek said.
While more research is again needed, the results suggest that thousands
of children worldwide could be at risk for genetic abnormalities because of
their fathers’ smoking, he said.
* When food becomes an obsession - Nutrition Notes: Binge eating is about more
than willpower
MSNBC, 2/10/98
Most of us overeat from time to time, some of us quite often. But for 1 to 2
million Americans, overeating isn’t just an occasional over-indulgence of a
favorite food — it’s a disease. These people suffer from binge eating
disorder, frequently eating large amounts of food while feeling a loss of
control over their eating.
ALTHOUGH MANY people with this disorder may be overweight, strict dieting
tends to worsen binge eating, so identifying the people for whom overeating
is not just a matter of willpower, and helping them to find appropriate
treatment is most important. Just eating large amounts of food does
not mean that a person has binge eating disorder. It is characterized by
frequent episodes of eating what others would consider an abnormally large
amount of food while feeling unable to control what or how much is being
eaten. People with the disorder may eat large amounts even when not
physically hungry; eat rapidly and until uncomfortably full; and hide their
binge eating out of shame or disgust. Binges are often triggered by anger,
sadness or other negative emotions. While people with binge eating
disorder do not face the dangers of compulsive vomiting and other methods of
purging that follow binges in the disorder bulimia nervosa, its damages
include obesity and possible high blood cholesterol, high blood pressure and
diabetes. In addition, the balanced plant- based diet and weight control that
can lower risk of cancer and other serious diseases are difficult for someone
with binge eating disorder to achieve. People with binge eating
disorder are extremely distressed by their binges. Most have tried using
willpower to control it on their own, but have not succeeded for long. Fueled
by our society’s attitude that overeating is a matter of self-control, obese
people with binge eating disorder tend to have poor self-esteem and may
become socially withdrawn. CAUSE REMAINS A MYSTERY The causes
of binge eating disorder are still unknown. Up to half of all people with the
disorder have a history of depression, but it is not clear whether it is a
cause or effect of the disorder, or if it is related at all. Research is
looking into how brain chemicals may affect binge eating. Strict dieting
generally worsens the tendency to binge. While weight loss may be an
important part of treatment for some of the medical problems that develop
because of binge eating and obesity, several studies have reported that
people with binge eating disorder find it harder to stay in weight loss
treatment and are likely to regain weight quickly. For this reason, experts
generally recommend that people with this disorder start with treatment
focusing on their binge eating before actually pursuing weight loss. Those
who are not overweight are often distressed by their binge eating and may
also benefit from treatment. Cognitive-behavioral therapy teaches
patients to change the way damaging thought patterns influence their eating
and responses to difficult situations. Interpersonal psychotherapy helps
people identify and improve problems in their relationships with friends and
family. Medications such as antidepressants may help some people.
Overeating, when frequently experienced as an uncontrollable response to
difficult situations or feelings, is not just a matter of self-control and
not a reason for shame. It is an eating disorder experienced by millions that
can be treated. Talk with your doctor or local eating disorder association to
learn more.
* Ask the expert : Fluctuating blood pressure, healthy triglyceride levels
MSNBC, 13/8/98
Q: My blood pressure can be 130/80 at one point in time and then go as high
as 185/95 within the next five minutes. Is this normal? A: The answer
depends on why the fluctuations occur. A sudden variance in blood pressure
like the one you describe may be the result of “white coat” hypertension — a
hike in blood pressure that occurs in some patients because the mere sight of
a doctor (in a white coat or otherwise) causes them to become nervous or
anxious. This stress can lead to a temporary blood-pressure reading that is
higher than normal. Patients susceptible to this phenomenon need to
have their blood pressure monitored on several occasions to determine whether
they truly have hypertension; measurements taken at home, where the patient
is relaxed, are often recommended. Another explanation for the
fluctuating readings is a faulty blood-pressure cuff that yields inconsistent
results. But only a physician can accurately determine the cause of
the variable readings, and prompt attention is advised if you haven’t already
sought medical help. Certain serious conditions, such as kidney disease, can
cause high blood pressure. Ideally, blood pressure should be kept
under 140/90. People can help keep their blood pressure under control by
exercising regularly and eating a low-fat diet that is rich in fruits and
vegetables. Q: My triglycerides are over 200. How important is the
triglyceride count? And are there ways to lower it? A: Like
cholesterol, triglycerides are a type of fat found in the blood. But while
substantial evidence exists that elevated cholesterol can lead to hardening
of the arteries, heart attack and stroke, the role of triglycerides in
cardiovascular health is not so clear. For instance, an elevated triglyceride
level has been linked to heart disease in some people, but not others.
The American Heart Association recommends that blood levels of
triglycerides be less than 200 milligrams per deciliter (mg/dL). A level of
200 to 400 mg/dL is considered borderline-high, and anything above is
considered high. Ideally, people should try to keep their triglycerides below
150 mg/dL. By reducing the saturated fat and cholesterol in your
diet, cutting down on extra calories and maintaining a regular exercise
program, you can help keep triglycerides in check. Dr. Sidney C.
Smith, a past president of the American Heart Association, is chief of the
division of cardiology at the University of North Carolina in Chapel Hill.
* Microsoft new release -- a printed dictionary
SAN FRANCISCO (Reuters, 2/10/98) - Microsoft will produce an analog product: a
printed dictionary.
The world's biggest software company, working with Britain's Bloomsbury
Publishing, New York-based St. Martin's Press, and Pan Macmillan Australia,
plans to publish the Encarta World English Dictionary in electronic and print
forms in August.
Hailing English as ``the first global language since Latin,'' the companies
said the collaboration would mark the first time that dictionaries for native
speakers of American and British English will be produced from a single
database. The dictionary will also be the first print product to bear the
Microsoft reference brand Encarta, which made its name from its electronic
encyclopedia.
The companies have been working together for three years on the dictionary,
which will include more than 3 million words of text and mark the start of a
long-term relationship aimed at developing content for print and electronic
reference works.
St. Martin's Press and Pan Macmillan Australia are part of Germany's
Verlagsgruppe Georg von Holtzbrinck publishing empire.
* Colon cancer rare among young people
WASHINGTON (AP, 2/10/98) - About 100,000 Americans are diagnosed each year
with colon cancer, the third deadliest of the cancer killers. But the disease
is rare among people as young as 36-year-old Darryl Strawberry, the New York
Yankees slugger whose tumor will be removed on Saturday.
If diagnosed early, colon cancer is highly curable: The cure rate for early
stage colon cancer is more than 92 percent, said Dr. Robert A. Smith of the
American Cancer Society.
``There is an excellent chance that with surgery and added chemotherapy, there
will be a complete cure and he will return to life as usual, including playing
baseball,'' Smith said of Strawberry.
Baltimore Orioles outfielder Eric Davis, a childhood friend of Strawberry's,
was treated for colon cancer last year, and he batted .327 in the season just
ended.
Having two boyhood friends, both in baseball, develop the same type of cancer
is a coincidence and not related to any shared environmental factor, Smith
said.
In the United States each year, there are only seven cases per 100,000 men
aged 36.
Yet no one is immune from colon cancer. It strikes men and women roughly
equally. President Reagan was treated for colon polyps, which can be a
precursor. The husband of TV's Katie Couric, NBC legal commentator Jay
Monahan, died of the disease in January.
And another ballplayer, Joel Stephens, who played for the Frederick Keys in
the Class A Carolina League, died Wednesday at age 22.
Public attention to the disease will undoubtedly increase with Strawberry's
diagnosis on top of Davis' and Couric's husband, said Dr. LaSalle D. Leffall
Jr., a cancer surgeon at Howard University Hospital in Washington.
``I think that the triple action is going to make people think to themselves,
`We have go to do something about it - watch our diet and get screening.'''
Colon cancer's precise cause is unknown. But researchers have linked it to
three major behavioral factors: alcohol consumption, a diet high in red meat
and fat, and lack of exercise, Smith said.
Heredity may also play a role. People with a family history of colon cancer
are more likely to get the disease, as are people who suffer from chronic
ulcers or inflammatory bowel disease.
Chewing tobacco, common among ballplayers, is not linked with colon cancer,
although it is a major cause of oral and esophageal cancer.
Colon cancer is twice as common among young black men as among young white
men, but studies suggest this is linked to lifestyle, not to race.
Americans' high-fat, low-fiber diets may increase the risk. It is less common
in Asia, where fruits and vegetables are a mainstay. When Asians move to the
United States and adopt the American diet, their risk rises to that of native-
born Americans, Smith said.
Colon cancer is one of the most easily detected cancers: Routine screen tests
usually find it.
Doctors found Strawberry's colon tumor after he complained of abdominal pains.
But most colon cancer is detected in screening tests that are now a routine
part of medical exams for people over age 40.
The cancer society recommends a rectal exam annually for people over 40. After
age 50, the experts say everyone should have a stool blood test. That requires
the patient to collect a stool smear at home and take it to a hospital or
clinic.
``The most common symptom is bleeding from the bowel, so this test can be
quite effective,'' said Smith.
For people over 50, the cancer society recommends an inspection of the colon
and rectum with a hollow, lighted tube, a test called a protosigmoidoscopy,
every three to five years.
If such tests find problems, doctors may then order X-ray procedures that can
involve long, flexible tubes, or barium enemas that put the entire colon in
view.
The first line of treatment is surgery, similar to what Strawberry will
undergo. Surgeons remove the tumor, along with adjacent parts of the colon.
Patients later are treated with drugs or radiation.
But the key is early detection, Smith said. And that means routine screening,
particularly for people over 50, the age group that experiences 90 percent of
colon cancers.
``People don't like those tests because they invade a private part of the
body,'' Smith said. ``But it can save lives.''
* Family claims wrong medicine left woman in coma-like state
TONAWANDA, N.Y. (AP, 2/10/98) - Kathleen Mayfield had long suffered migraines.
One evening this summer she took a pill to help her relax and lay down on her
couch.
Three months later, her husband and eight children don't know whether she'll
ever wake up.
The Town of Tonawanda family claims a pharmacy gave the 43-year-old woman the
wrong prescription. Instead of helping her relax, her husband Bruce said, the
pill she took severely lowered her blood sugar and left her in a coma-like
state.
Now Mayfield and the children, ages 11 to 21, hold family vigils at Mrs.
Mayfield's bedside at Our Lady of Victory Hospital, searching for hope in the
flutter of an eyelid or blinking of an eye.
The family has filed a $15 million negligence suit against the Kenmore
pharmacy and the pharmacist who filled the prescription.
``It's really devastating the family,'' the Mayfields' attorney Patrick Brown
told The Buffalo News.
Donald Fleming is identified in the lawsuit as the pharmacist at Ivylea
Prescription and Home Health Care Center in Kenmore who dispensed the drug.
He declined comment. The attorney for Ivylea couldn't be reached Friday.
Employees at the pharmacy also wouldn't comment.
The lawsuit alleges that Fleming gave Mrs. Mayfield ``a prescription bottle
containing medication different from the medication named on the label of the
bottle and which contained a medication other than the one called for in the
prescription.''
Mrs. Mayfield's doctors would not discuss the case because of the pending
litigation.
Mayfield, a steel cutter at Dunlop Tire Corp., has been on unpaid family leave
since the incident, although he plans to return to work soon.
Insurance pays for part of the hospital bills, which can add up to $800 a day,
but debts are mounting.
Mayfield's co-workers at Dunlop recently held a benefit for the family. An
Oct. 9 event also is planned by the Town of Tonawanda Police Club.
Mrs. Mayfield's brother, Dan Murphy, is a Town of Tonawanda police officer. He
was on the night shift when the 911 call came in from the Mayfield home.
Recognizing the address, he arrived with paramedics to find his sister
unconscious.
``There's nothing we can do for Kathleen now. That's up to the doctors,''
Murphy said. ``But we can help the family.''
Mayfield said his wife has remained motionless and unresponsive but opens and
closes her eyes and moves in and out of cycles of sleep and wakefulness.
But encouraging as even the slightest responses are, they aren't consistent.
Unless that happens, her doctors won't consider Mrs. Mayfield to be making
progress, her husband said.
* The hits keep coming
The Boston Globe, 28/9/98
You watch a 230-pound NFL quarterback take a vicious sack and you wince. He
struggles to his feet, shaking his head, trying to clear the cobwebs. Perhaps
he needs to be helped to the sidelines, where a trainer holds up his fingers
and asks ''How many?'' The TV cameras capture it all.
What you probably don't see and seldom think about is the 330-pound guard,
smashing himself into a 340-pound tackle who's hurtling at him. Forty times a
game. Sixteen games a season. Fifty times a week in practice. Fifty times a
day in training camp.
That's 2,530 pounding collisions a season, crunching a spine that, likely as
not, will protest sooner or later.
''In a 10-year career, figure it out,'' challenges Dr. Warren King, team
physician for the Oakland Raiders. ''Lineman is the one position on the field
that makes contact with another player all the time, and often contact with
multiple players.''
Tack on four years of college, four years of high school and a couple of Pop
Warner seasons and the number of hits is staggering: well upwards of 100,000.
And as linemen get bigger - there were 279 players on the NFL rosters last
week who weighed at least 300 pounds - the impact is only getting greater.
Even before they get out of college, one study reports, up to 50 percent of
football players report lower back pain, and the majority of them are the
guys in the trenches. In another study, almost 50 percent of down linemen -
who start each play from the familiar three-point stance - showed X-ray
evidence of accelerated wear and tear to the lower spine.
''It's the occupational hazard of playing football,'' said Dr. Kevin P. Speer,
associate professor of orthopedic surgery at Duke University and physician for
its varsity teams. ''You're taking very large men who are very strong and
having them hit each other as hard as possible.''
Interestingly, the straight-on impact of a football block doesn't produce much
more force on the lower spine than a powerful golf swing or sweep of an oar,
and the force is almost identical to that of a squat lift in weightlifting.
Football has not, by any means, cornered the market on back problems, as
golfers, rowers and lifters will attest. But the lineman's lumbar spine is at
special risk, probably because of the way he must drive upward and rapidly
change direction at the time of collision.
''We know the incidence of stress fractures is much higher in offensive
linemen than it is in the general population,'' says Dr. Charles Gatt, a
sports medicine orthopedic surgeon at Robert Wood Johnson University Hospital
in New Brunswick, N.J. What Gatt found in his study, using five college
football linemen attacking blocking sleds, is that the repetition of the
mechanics of blocking may be the reason linemen suffer more back problems
than players at other positions. ''Forces are high, but not high enough to
cause a single traumatic injury,'' said Gatt.
So the question becomes, if the damage is compounded by overuse, how do you
cut down on that without sacrificing the quality of play?
For starters, linemen try to reduce their weight for the offseason, says King,
a member of the Association of Professional Team Physicians. And increasingly,
they stay in better shape year-round, so they come to training camp each year
with a better baseline of fitness.
Perhaps most importantly, ''Most teams [at the pro level] nowadays don't do
any significant tackling in practice,'' he said. ''Before, they used to hit a
lot more than they do now.''
Emphasizing technique rather than impact during practice, along with proper
weight lifting techniques to strengthen muscles in the lower back, seem to be
two keys to reducing wear and tear. But the college coach with the second-best
lifetime record in history goes even further.
''We eliminate whatever we think is not necessary to win, and I think most
everything is unnecessary,'' said John Gagliardi, coach at Saint John's
University in Collegeville, Minn. ''The more you're out there [on the practice
field], the more you're apt to get injured.''
So Gagliardi, whose teams were 342-104-11 coming into this season, is wary of
too much contact in practice. No blocking sleds. No rough stuff. No
calisthenics, even. And very few injuries.
''You'd better win with that style,'' said Gagliardi, in his 50th year of
coaching. ''Otherwise, they'll think you're nuts.''
Yet Gagliardi is well aware that what flies at a smaller, Division 3 program
such as Saint John's won't necessarily work elsewhere, especially where the
stakes are higher.
''It's part of what they do,'' says King of professional athletes. ''They give
up some of their health in order to make money playing.''
But it's not just the money. When Speer, the Duke team physican, warns linemen
of the possibility of degenerative spine problems and pain later in life, they
don't exactly shrug, but they don't quit, either.
He certainly didn't. ''The game of football has so many stresses, after a
time a price has to be paid,'' says Speer, himself a former lineman who does
exercises and stretches every day to keep his back from misbehaving. ''Would
I otherwise, at 39, have to do the stretches? Maybe, maybe not. If I had to
do it all over again, I'd play football in a heartbeat.''
* How & Why
The Boston Globe, 28/9/98
Q. If there is no oxygen in space, then how do the sun and other stars burn
with apparent flames?
R.C. Jr.
Goodyear, Ariz.
A. As hot as the sun may be making you in Arizona, it's not really burning at
all. It's fusing.
Burning is a chemical reaction that involves the electrons in the outer shells
of atoms in the fuel. Oxygen is part of what's necessary for the chemical
reaction. But the sun and other stars create their energy by fusing the nuclei
at the center of hydrogen atoms. The single-proton nuclei from each of four
hydrogen atoms fuse into a single nucleus of helium that has two protons and
two neutrons. But the helium nucleus winds up with a smaller mass than the sum
of those four hydrogen nuclei that fused together.
The difference is energy. Lots of energy.
Einstein's famous equation E=mc2 translates to: energy equals mass times the
speed of light squared. Well, the mass lost in fusing that tiny helium nucleus
isn't very much at all. But the speed of light is 186,000 miles per second.
Squared, that's 34,596,000,000. Multiply that times even the tiniest value for
mass, and you've got lots of energy.
Fusion creates one million times more energy, per atom, than chemical burning.
Who needs oxygen when you've got that kind of power available!
We can create the staggering power of the sun here on Earth, in the form of a
hydrogen fusion bomb. But finding a way to use an on-going, self-sustaining
nuclear fusion reaction for a controllable energy source has engineers
stumped. Since temperatures reach five million degrees at the center of the
sun, standard materials can't be used to build a container to hold such a
reaction. Scientists have built machines called Tokamaks that use magnetic
fields to do the job, but they haven't been able to hold the fuel long enough
to reach ignition, the point at which the reaction becomes self-sustaining.
That's what the sun does with fusion, and what nuclear power plants do with
fission reactions, which split nuclei apart instead of fusing them together.
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