Evidence
points to ring around Saturn moon:Study
LONDON,
Mar 7:
Saturn's second-largest moon Rhea may have a
small ring around it -- the first time a moon has
been found to have a ring, an international team
of researchers reported.
The findings from
the Cassini spacecraft, published in the journal
Science, will help scientists better understand
how planets form, said Geraint Jones, who worked
on the study while at the Max Planck Institute in
Germany.
The four largest
planets in the solar system -- Jupiter, Neptune,
Saturn and Uranus -- all have rings and Earth
probably had one as well at some point billions
of years ago, before its moon even existed, Jones
said in a telephone interview.
''All planets when
they were forming probably had rings at various
times,'' he said. ''It is fascinating to find one
possibly around a small body like Rhea, which is
still with us today.''
The Cassini
spacecraft was launched in 1997 to examine
Saturn. Last month scientists said evidence from
the joint European-US mission pointed to the
presence of water beneath the frozen surface of
another of Saturn's moons, Enceladus.
The researchers
believe the latest data point to a ring because
when Cassini recently flew past Rhea they
detected a surprising lack of electrons
surrounding the moon.
Rhea lies within a
magnetised bubble that surrounds Saturn and
contains trapped ions and electrons. Because of
this, the researchers expected to see electrons
trailing off closer to the surface as the moon
absorbed them.
Instead, the
electrons disappeared much sooner -- as if
something was blocking them -- leaving a ring of
debris as the most likely explanation, Jones
said.
''There is
evidence something is absorbing electrons around
this moon,'' he said. ''A debris disk around the
moon is the simplest explanation we can come up
with that fits with the data we have.''
The ring probably
formed when a smaller body smashed into Rhea and
sent out a stream of debris that began orbiting
the moon, said Iannis Dandouras, a planetary
scientist at the National Centre for Scientific
Research in France who also worked on the study.
The evidence of a
ring is also interesting because it shows that
the material was not incorporated into Rhea but
was ejected into orbit, Dandouras added.
''It is the first
time we found a system of planetary rings around
a satellite of a planet,'' Dandouras said. ''A
planetary ring tells us the story about the
historical formation of moons and planets.''
(AGENCIES)
Telling
smokers "age" of lungs helps them
quit:Study
LONDON,
Mar 7:
Smokers are more likely to kick the habit if they
are told how ''old'' their lungs are, a British
study found today.
The concept of
lung age -- measured by comparing a smoker's
lungs to the age of a healthy person whose lungs
function the same -- has helped patients better
understand how smoking damages health,
researchers had already found.
But that
information is also effective in convincing
smokers to quit, said Gary Parkes, a family
physician in Hertfordshire outside London, who
led the study published in the British Medical
Journal.
''Telling smokers
their lung age significantly improves the
likelihood of them quitting smoking,'' Parkes and
his colleagues wrote.
Smoking kills
about four million people each year, according to
the World Health Organisation. Tobacco is highly
addictive and the leading preventable cause of
both cancer and heart disease.
The study in five
general medical practices outside London involved
561 long-term smokers older than 35 and began
with a simple test to record the volume and rate
at which the volunteers exhaled air from the
lungs.
One group received
no detailed information about their results while
the other people were given their lung age, shown
a diagram of how smoking ages the lungs and told
that quitting would slow the rate of damage.
Everyone was also
strongly encouraged to quit and offered help to
do so. One year later, saliva tests showed that
13 per cent of the smokers told their lung age
had quit while only 6 per cent of people in the
other group had stopped.
''Anybody who had
good, understandable information seemed more
inclined to give up,'' Parkes said. ''The reason
may be people had dreaded the worst and realized
it was still worthwhile giving up.''
The study counters
research showing such health information does not
prod them to quit and underscores the benefits of
early screening because 16 per cent of the people
in the study had undiagnosed emphysema, Parkes
said.
Giving people this
kind of information could represent a cheap and
easy way to get people to stop smoking and reduce
smoking-related health problems that are putting
pressure on health systems to treat.
''The cost, if you
like, is certainly within the economic framework
of a good deal,'' Parkes said. (AGENCIES)
Hundreds
evacuated in Calif university bomb scare
SAN
FRANCISCO, Mar 7: More than 450 students were
evacuated from dormitories at University of
California Davis and spent the night in a
cafeteria after police found explosive materials
in a student's room, officials said.
Police arrested
Mark Christopher Woods, 19, an economics major
from Torrance, California, on charges of
possessing chemicals to make explosives and
having explosive materials on school grounds,
police and school officials said.
Terrorism was not
suspected.
''We evacuated
students as a precaution. We do not expect
further disruption to the university,'' Fred
Wood, vice chancellor for student affairs, said
in a statement.
''We are confident
that university police and other local law
enforcement agencies have the situation
contained.''
The university
said it evacuated 455 first-year students at
around 9 pm on Wednesday (1030 hrs IST) yesterday
after police got a telephone tip about the
suspected explosive materials.
The US Bureau of
Alcohol, Tobacco, Firearms and Explosives said in
a statement a search began about 5 am and
continued through the day. The ATF forensic
laboratory will analyze the evidence.
Davis is located
between the state capital, Sacramento, and San
Francisco.
(AGENCIES)
US
soldiers show mental strain from combat tours
WASHINGTON,
Mar 7:
More than a quarter of US soldiers on their third
or fourth tours in Iraq suffer mental health
problems partly because troops are not getting
enough time at home between deployments, the Army
said.
Overall, about
17.9 per cent of soldiers in Iraq and Afghanistan
had mental health problems in 2007, according to
an annual Army survey revealed yesterday. That is
slightly below the 2006 figure of 19.1 per cent
but relatively consistent with previous years.
But the incidence
of mental health problems for soldiers in war
zones climbs significantly among troops returning
for a third and fourth combat tour, the survey
showed.
Among
noncommissioned officers, for example, 27.2 per
cent on their third and fourth tours suffered
mental health problems in 2007. That compares
with 18.5 per cent for those low-ranking officers
on their second tours and 11.9 per cent of those
on their first tours, the Army said.
''Soldiers are not
resetting entirely before they get back into
theater,'' said Lt Col Paul Bliese, who led the
Army's Mental Health Advisory Team survey for
2007.
By ''resetting''
Bliese meant soldiers are not getting enough time
to recover from the trauma of duty in a war zone.
''They're not
having the opportunity, and we bring this up in
the report, to completely recover from previous
deployment and then go back into theater.''
Bliese attributed
the problem to the relatively short ''dwell
time'' -- the period a soldier has at home
between deployments.
Soldiers now have
only 12 months at home before their next
deployment. The Army's goal is to give soldiers
three years at home for every one year deployed,
but officials admit that is not realistic given
current combat requirements in Iraq and
Afghanistan.
PERSONAL PROBLEMS
Short dwell times
helped the Pentagon execute President George W
Bush's troop ''surge'' last year that boosted
troop levels in Iraq to 160,000 and keep about
28,000 troops in Afghanistan.
It also allowed
the Pentagon to extend all Army deployments in
the West Asia to 15 months from 12, a move needed
to sustain that ''surge'' of forces in Iraq last
year.
While those steps
helped improve security in Iraq, the survey shows
they also increased stress on an already strained
force and seemed to contribute to work and
personal problems.
''We see this
multiple deployment effect for the mental health
problems. We see a similar pattern for morale. We
see some of the same reporting for job-related
problems,'' Bliese said.
The military has
struggled to meet troops' medical needs -- both
mental and physical. The Pentagon has been trying
to reform the health system since a Washington
Post report last year that wounded troops
returning from Iraq and Afghanistan faced neglect
at Walter Reed, the premier military hospital.
The 2007 Army
mental health study surveyed 2,295 soldiers in
Iraq and 699 in Afghanistan.
Soldiers in 2007
reported more difficulty accessing behavioral
health services than in previous years despite
the Army's year-long effort to hire more health
professionals.
Part of the
problem is linked to higher troop numbers in the
war zones, said Col Elspeth Ritchie, a
psychiatrist and consultant to the Army Surgeon
General.
In 2007, there was
one practitioner for every 734 soldiers compared
with one per 658 soldiers in 2006, Ritchie said.
The problem is
also related to the US military's decision to
push its soldiers farther away from bases, where
many medical services are housed, so that they
can work with local security personnel and
interact with the community.
The Army is trying
to hire 275 additional mental health
professionals from the civilian sector in the
United States plus others in Europe and Korea. A
tight labor market and difficulty getting
civilian practitioners into the war zones has
hurt the effort, Ritchie said.
(AGENCIES)
Surgery
may cure Type 2 diabetes: Study
WASHINGTON,
Mar 7:
Diabetics can now take heart as new research
shows that Type 2 Diabetes cam be effectively
cured by surgery as it may be disorder of uppes
intestive.
The study's
author, Dr Francesco Rubino, professor in the
Department of Surgery at Weill Cornell Medical
College and chief of gastrointestinal metabolic
surgery at NewYork-Presbyterian/Weill Cornell,
pointed to the small bowel as the possible site
of critical mechanisms for the development of
diabetes.
Clinical studies
have shown that procedures that restrict the
stomach's size ie, gastric banding improve
diabetes only by inducing massive weight loss.
By studying
diabetes in animals, Dr Rubino has provided
scientific evidence that gastrointestinal bypass
operations involving rerouting the
gastrointestinal tract (ie, gastric bypass) can
cause diabetes remission independently of any
weight loss, and even in subjects that are not
obese.
''By answering the
question of how diabetes surgery works, we may be
answering the question of how diabetes itself
works,'' Sciencedaily quoted him as saying.
''When we bypass
the duodenum and jejunum, we are bypassing what
may be the source of the problem,'' said Dr
Rubino, who is heading the
NewYork-Presbyterian/Weill Cornell's Diabetes
Surgery Center.
In fact, it has
become increasingly evident that the
gastrointestinal tract plays an important role in
energy regulation, and that many gut hormones are
involved in the regulation of sugar metabolism.
''It should not
surprise anyone that surgically altering the
bowel's anatomy affects the mechanisms that
regulate blood sugar levels, eventually
influencing diabetes,'' Dr Rubino said.
''When performed
in subjects who were not diabetic, the bypass of
the upper intestine may even impair the
mechanisms that regulate blood levels of
glucose,'' he added.
In striking
contrast, when nutrients' passage is diverted
from the upper intestine of diabetic patients,
diabetes resolves, he pointed out.
This, he
explained, implies that the upper intestine of
diabetic patients may be the site where an
abnormal signal is produced, causing, or at least
favoring, the development of the disease.
''In healthy
patients, a correct balance between incretin and
anti-incretin factors maintains normal excursions
of sugar levels in the bloodstream,'' he further
explained.
''In some
individuals, the duodenum and jejunum may be
producing too much of this anti-incretin, thereby
reducing insulin secretion and blocking the
action of insulin, ultimately resulting in Type 2
diabetes,'' he added.
(UNI)
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