NEW CHANDRA MOVIE FEATURES NEUTRON STAR ACTION
WASHINGTON -- Unlike with some blockbuster films, the sequel to a
movie from NASA's Chandra X-ray Observatory is better than the first.
This latest movie features a deeper look at a fast moving jet of
particles produced by a rapidly rotating neutron star, and may
provide new insight into the nature of some of the densest matter in
the universe.
The hero of this Chandra movie is the Vela pulsar, a neutron star that
was formed when a massive star collapsed. The Vela pulsar is about
1,000 light-years from Earth, about 12 miles in diameter, and makes a
complete rotation in 89 milliseconds, faster than a helicopter rotor.
As the pulsar whips around, it spews out a jet of charged particles
that race along the pulsar's rotation axis at about 70 percent of the
speed of light. The new Chandra data, which were obtained from June
to September 2010, suggest the pulsar may be slowly wobbling, or
precessing, as it spins. The period of the precession, which is
analogous to the slow wobble of a spinning top, is estimated to be
about 120 days.
"We think the Vela pulsar is like a rotating garden sprinkler --
except with the water blasting out at over half the speed of light,"
said Martin Durant of the University of Toronto in Canada, who is the
first author of the paper describing these results.
One possible cause of precession for a spinning neutron star is it has
become slightly distorted and is no longer a perfect sphere. This
distortion might be caused by the combined action of the fast
rotation and "glitches," sudden increases of the pulsar's rotational
speed due to the interaction of the superfluid core of the neutron
star with its crust.
"The deviation from a perfect sphere may only be equivalent to about
one part in 100 million," said co-author Oleg Kargaltsev of The
George Washington University in Washington, who presented these
results Monday at the 221st American Astronomical Society meeting in
Long Beach, Calif. "Neutron stars are so dense that even a tiny
distortion like this would have a big effect."
If the evidence for precession of the Vela pulsar is confirmed, it
would be the first time a neutron star has been found to be this way.
The shape and the motion of the Vela jet look strikingly like a
rotating helix, a shape that is naturally explained by precession.
Another possibility is the strong magnetic fields around the pulsar
are influencing the shape of the jet. For example, if the jet
develops a small bend caused, by precession, the magnetic field's
lines on the inside of the bend will become more closely spaced. This
pushes particles toward the outside of the bend, increasing the
effect.
"It's like having an unsecured fire hose and a flow of water at high
pressure," said co-author George Pavlov, principal investigator of
the Chandra proposal at Pennsylvania State University in University
Park. "All you need is a small bend in the hose and violent motion
can result."
This is the second Chandra movie of the Vela pulsar. The original was
released in 2003 by Pavlov and co-authors. The first Vela movie
contained shorter, unevenly spaced observations so that the changes
in the jet were less pronounced and the researchers did not argue
that precession was occurring. However, based on the same data,
Avinash Deshpande of Arecibo Observatory in Puerto Rico and the Raman
Research Institute in Bangalore, India, and the late Venkatraman
Radhakrishnan, argued in a 2007 paper the Vela pulsar might be
precessing.
Astronomers have returned to observing Vela because it offers an
excellent chance to study how a pulsar and its jet work. The 0.7
light-year-long jet in Vela is similar to those produced by accreting
supermassive black holes in other galaxies, but on a much smaller
scale. Because Vela's jet changes dramatically over a period of
months and is relatively close, it can be studied in great detail
unlike jets from black holes that change over much longer timescales.
If precession is confirmed and the Vela pulsar is indeed a distorted
neutron star, it should be a persistent source of gravitational
waves, and would be a prime target for the next generation of
gravitational wave detectors designed to test Einstein's theory of
general relativity.
A paper describing these results will be published in Thursday's The
Astrophysical Journal. Other co-authors of the paper were Julia
Kropotina and Kseniya Levenfish from St. Petersburg State
Polytechnical University in St. Petersburg, Russia.
NASA's Marshall Space Flight Center in Huntsville, Ala., manages the
Chandra program for NASA's Science Mission Directorate in Washington.
The Smithsonian Astrophysical Observatory controls Chandra's science
and flight operations from Cambridge, Mass.
Wednesday, January 9, 2013
Peanut allergy: New methods to treat allergy to peanuts
Peanut Therapy Shows Promise in Treating Peanut Allergy
NIH-Funded Clinical Study is One of the First to Evaluate Sublingual Immunotherapy as a Peanut Allergy Treatment
A new study supported by the National Institutes of Health (NIH) suggests that sublingual immunotherapy (SLIT) can reduce the allergic response to peanut in adolescents and adults. SLIT is a treatment approach in which, under medical supervision, people place a small amount of allergen under the tongue to decrease their sensitivity to the allergen. This is one of the first randomized, placebo-controlled studies to test the efficacy and safety of SLIT to treat peanut allergy and is one of several federally funded trials investigating immune-based approaches to preventing and treating food allergy. The results appear online in the January issue of the Journal of Allergy and Clinical Immunology.
The study enrolled 40 people aged 12 to 37 years with peanut allergy who were on a peanut-free diet. After an initial food challenge to measure how much peanut powder they could eat without having an allergic reaction, participants received 44 weeks of daily therapy, followed by a second food challenge. Fourteen of the 20 participants (70 percent) given peanut SLIT were able to consume at least 10 times more peanut powder than they could at the beginning of the study, compared with only 3 of the 20 participants (15 percent) given placebo. After 68 weeks on peanut SLIT, on average, participants could consume significantly more peanut powder without having an allergic reaction. Study investigators also observed that SLIT caused only minor side effects, such as itching in the mouth, suggesting that daily therapy is safe.
Although more work is needed, the investigators hope that SLIT could one day help protect people with peanut allergy from experiencing severe allergic reactions in cases of accidental exposure. The researchers caution that people should not try peanut SLIT on their own because any form of immunotherapy carries a significant risk for allergic reactions. The therapy should be administered only under the guidance of trained clinicians.
The multicenter study was supported by the NIH’s National Institute of Allergy and Infectious Diseases (NIAID) and conducted by the Consortium of Food Allergy Research (CoFAR) at clinical sites in Baltimore; Chapel Hill, N.C.; Denver; Little Rock, Ark.; and New York City. CoFAR investigators David Fleischer, M.D., associate professor of pediatrics in the Division of Pediatric Allergy and Immunology at National Jewish Health in Denver, and A. Wesley Burks, M.D., chair of the Department of Pediatrics at the University of North Carolina, Chapel Hill, led the trial.
461 new planet candidates found in the universe, totaling potential planets to 2740 orbiting 2036 stars
NASA'S KEPLER MISSION DISCOVERS 461 NEW PLANET CANDIDATES
WASHINGTON -- NASA's Kepler mission Monday announced the discovery of
461 new planet candidates. Four of the potential new planets are less
than twice the size of Earth and orbit in their sun's "habitable
zone," the region in the planetary system where liquid water might
exist on the surface of a planet.
Based on observations conducted from May 2009 to March 2011, the
findings show a steady increase in the number of smaller-size planet
candidates and the number of stars with more than one candidate.
"There is no better way to kickoff the start of the Kepler extended
mission than to discover more possible outposts on the frontier of
potentially life bearing worlds," said Christopher Burke, Kepler
scientist at the SETI Institute in Mountain View, Calif., who is
leading the analysis.
Since the last Kepler catalog was released in February 2012, the
number of candidates discovered in the Kepler data has increased by
20 percent and now totals 2,740 potential planets orbiting 2,036
stars. The most dramatic increases are seen in the number of
Earth-size and super Earth-size candidates discovered, which grew by
43 and 21 percent respectively.
The new data increases the number of stars discovered to have more
than one planet candidate from 365 to 467. Today, 43 percent of
Kepler's planet candidates are observed to have neighbor planets.
"The large number of multi-candidate systems being found by Kepler
implies that a substantial fraction of exoplanets reside in flat
multi-planet systems," said Jack Lissauer, planetary scientist at
NASA's Ames Research Center in Moffett Field, Calif. "This is
consistent with what we know about our own planetary neighborhood."
The Kepler space telescope identifies planet candidates by repeatedly
measuring the change in brightness of more than 150,000 stars in
search of planets that pass in front, or "transit," their host star.
At least three transits are required to verify a signal as a
potential planet.
Scientists analyzed more than 13,000 transit-like signals to eliminate
known spacecraft instrumentation and astrophysical false positives,
phenomena that masquerade as planetary candidates, to identify the
potential new planets.
Candidates require additional follow-up observations and analyses to
be confirmed as planets. At the beginning of 2012, 33 candidates in
the Kepler data had been confirmed as planets. Today, there are 105.
"The analysis of increasingly longer time periods of Kepler data
uncovers smaller planets in longer period orbits-- orbital periods
similar to Earth's," said Steve Howell, Kepler mission project
scientist at Ames. "It is no longer a question of will we find a true
Earth analogue, but a question of when."
The complete list of Kepler planet candidates is available in an
interactive table at the NASA Exoplanet Archive. The archive is
funded by NASA's Exoplanet Exploration Program to collect and make
public data to support the search for and characterization of
exoplanets and their host stars.
Ames manages Kepler's ground system development, mission operations
and science data analysis. NASA's Jet Propulsion Laboratory (JPL) in
Pasadena, Calif., managed Kepler mission development. Ball Aerospace
and Technologies Corp. in Boulder, Colo., developed the Kepler flight
system and supports mission operations with JPL at the Laboratory for
Atmospheric and Space Physics at the University of Colorado in
Boulder.
The Space Telescope Science Institute in Baltimore archives, hosts and
distributes the Kepler science data. Kepler is NASA's 10th Discovery
Mission and is funded by NASA's Science Mission Directorate at the
agency's headquarters in Washington.
JPL manages NASA's Exoplanet Exploration Program. The NASA Exoplanet
Archive is hosted at the Infrared Processing and Analysis Center at
the California Institute of Technology.
WASHINGTON -- NASA's Kepler mission Monday announced the discovery of
461 new planet candidates. Four of the potential new planets are less
than twice the size of Earth and orbit in their sun's "habitable
zone," the region in the planetary system where liquid water might
exist on the surface of a planet.
Based on observations conducted from May 2009 to March 2011, the
findings show a steady increase in the number of smaller-size planet
candidates and the number of stars with more than one candidate.
"There is no better way to kickoff the start of the Kepler extended
mission than to discover more possible outposts on the frontier of
potentially life bearing worlds," said Christopher Burke, Kepler
scientist at the SETI Institute in Mountain View, Calif., who is
leading the analysis.
Since the last Kepler catalog was released in February 2012, the
number of candidates discovered in the Kepler data has increased by
20 percent and now totals 2,740 potential planets orbiting 2,036
stars. The most dramatic increases are seen in the number of
Earth-size and super Earth-size candidates discovered, which grew by
43 and 21 percent respectively.
The new data increases the number of stars discovered to have more
than one planet candidate from 365 to 467. Today, 43 percent of
Kepler's planet candidates are observed to have neighbor planets.
"The large number of multi-candidate systems being found by Kepler
implies that a substantial fraction of exoplanets reside in flat
multi-planet systems," said Jack Lissauer, planetary scientist at
NASA's Ames Research Center in Moffett Field, Calif. "This is
consistent with what we know about our own planetary neighborhood."
The Kepler space telescope identifies planet candidates by repeatedly
measuring the change in brightness of more than 150,000 stars in
search of planets that pass in front, or "transit," their host star.
At least three transits are required to verify a signal as a
potential planet.
Scientists analyzed more than 13,000 transit-like signals to eliminate
known spacecraft instrumentation and astrophysical false positives,
phenomena that masquerade as planetary candidates, to identify the
potential new planets.
Candidates require additional follow-up observations and analyses to
be confirmed as planets. At the beginning of 2012, 33 candidates in
the Kepler data had been confirmed as planets. Today, there are 105.
"The analysis of increasingly longer time periods of Kepler data
uncovers smaller planets in longer period orbits-- orbital periods
similar to Earth's," said Steve Howell, Kepler mission project
scientist at Ames. "It is no longer a question of will we find a true
Earth analogue, but a question of when."
The complete list of Kepler planet candidates is available in an
interactive table at the NASA Exoplanet Archive. The archive is
funded by NASA's Exoplanet Exploration Program to collect and make
public data to support the search for and characterization of
exoplanets and their host stars.
Ames manages Kepler's ground system development, mission operations
and science data analysis. NASA's Jet Propulsion Laboratory (JPL) in
Pasadena, Calif., managed Kepler mission development. Ball Aerospace
and Technologies Corp. in Boulder, Colo., developed the Kepler flight
system and supports mission operations with JPL at the Laboratory for
Atmospheric and Space Physics at the University of Colorado in
Boulder.
The Space Telescope Science Institute in Baltimore archives, hosts and
distributes the Kepler science data. Kepler is NASA's 10th Discovery
Mission and is funded by NASA's Science Mission Directorate at the
agency's headquarters in Washington.
JPL manages NASA's Exoplanet Exploration Program. The NASA Exoplanet
Archive is hosted at the Infrared Processing and Analysis Center at
the California Institute of Technology.
Tracing history of a black hole 11 billion years ago: Scientists find the source of ancient outburst in the farther space
GALAXY'S GAMMA-RAY FLARES ERUPTED FAR FROM ITS BLACK HOLE
WASHINGTON -- In 2011, a months-long blast of energy launched by an
enormous black hole almost 11 billion years ago swept past Earth.
Using a combination of data from NASA's Fermi Gamma-ray Space
Telescope and the National Science Foundation's Very Long Baseline
Array (VLBA), the world's largest radio telescope, astronomers have
zeroed in on the source of this ancient outburst.
Theorists expect gamma-ray outbursts occur only in close proximity to
a galaxy's central black hole, the powerhouse ultimately responsible
for the activity. A few rare observations suggested this is not the
case.
The 2011 flares from a galaxy known as 4C +71.07 now give astronomers
the clearest and most distant evidence that the theory still needs
some work. The gamma-ray emission originated about 70 light-years
away from the galaxy's central black hole.
The 4C +71.07 galaxy was discovered as a source of strong radio
emission in the 1960s. NASA's Compton Gamma-Ray Observatory, which
operated in the 1990s, detected high-energy flares, but the galaxy
was quiet during Fermi's first two and a half years in orbit.
In early November 2011, at the height of the outburst, the galaxy was
more than 10,000 times brighter than the combined luminosity of all
of the stars in our Milky Way galaxy.
"This renewed activity came after a long slumber, and that's important
because it allows us to explicitly link the gamma-ray flares to the
rising emission observed by radio telescopes," said David Thompson, a
Fermi deputy project scientist at NASA's Goddard Space Flight Center
in Greenbelt, Md.
Located in the constellation Ursa Major, 4C +71.07 is so far away that
its light takes 10.6 billion years to reach Earth. Astronomers are
seeing this galaxy as it existed when the universe was less than
one-fourth of its present age.
At the galaxy's core lies a supersized black hole weighing 2.6 billion
times the sun's mass. Some of the matter falling toward the black
hole becomes accelerated outward at almost the speed of light,
creating dual particle jets blasting in opposite directions. One jet
happens to point almost directly toward Earth. This characteristic
makes 4C +71.07 a blazar, a classification that includes some of the
brightest gamma-ray sources in the sky.
Boston University astronomers Alan Marscher and Svetlana Jorstad
routinely monitor 4C +71.07 along with dozens of other blazars using
several facilities, including the VLBA.
The instrument's 10 radio telescopes span North America, from Hawaii
to St. Croix in the U.S. Virgin Islands, and possess the resolving
power of a single radio dish more than 5,300 miles across when their
signals are combined. As a result, The VLBA resolves detail about a
million times smaller than Fermi's Large Area Telescope (LAT) and
1,000 times smaller than NASA's Hubble Space Telescope.
In autumn 2011, the VLBA images revealed a bright knot that appeared
to move outward at a speed 20 times faster than light.
"Although this apparent speed was an illusion caused by actual motion
almost directly toward us at 99.87 percent the speed of light, this
knot was the key to determining the location where the gamma-rays
were produced in the black hole's jet," said Marscher, who presented
the findings Monday at the American Astronomical Society meeting in
Long Beach, Calif.
The knot passed through a bright stationary feature of the jet, which
the astronomers refer to as its radio "core," on April 9, 2011. This
occurred within days of Fermi's detection of renewed gamma-ray
flaring in the blazar. Marscher and Jorstad noted that the blazar
brightened at visible wavelengths in step with the higher-energy
emission.
During the most intense period of flaring, from October 2011 to
January 2012, the scientists found the polarization direction of the
blazar's visible light rotated in the same manner as radio emissions
from the knot. They concluded the knot was responsible for the
visible and the gamma-ray light, which varied in sync.
This association allowed the researchers to pinpoint the location of
the gamma-ray outburst to about 70 light-years from the black hole.
The astronomers think that the gamma rays were produced when electrons
moving near the speed of light within the jet collided with visible
and infrared light originating outside of the jet. Such a collision
can kick the light up to much higher energies, a process known as
inverse-Compton scattering.
The source of the lower-energy light is unclear at the moment. The
researchers speculate the source may be an outer, slow-moving sheath
that surrounds the jet. Nicholas MacDonald, a graduate student at
Boston University, is investigating how the gamma-ray brightness
should change in this scenario to compare with observations.
"The VLBA is the only instrument that can bring us images from so near
the edge of a young supermassive black hole, and Fermi's LAT is the
only instrument that can see the highest-energy light from the
galaxy's jet," said Jorstad.
NASA's Fermi Gamma-ray Space Telescope is an astrophysics and particle
physics partnership. Fermi is managed by NASA's Goddard Space Flight
Center. It was developed in collaboration with the U.S. Department of
Energy, with contributions from academic institutions and partners in
France, Germany, Italy, Japan, Sweden and the United States.
WASHINGTON -- In 2011, a months-long blast of energy launched by an
enormous black hole almost 11 billion years ago swept past Earth.
Using a combination of data from NASA's Fermi Gamma-ray Space
Telescope and the National Science Foundation's Very Long Baseline
Array (VLBA), the world's largest radio telescope, astronomers have
zeroed in on the source of this ancient outburst.
Theorists expect gamma-ray outbursts occur only in close proximity to
a galaxy's central black hole, the powerhouse ultimately responsible
for the activity. A few rare observations suggested this is not the
case.
The 2011 flares from a galaxy known as 4C +71.07 now give astronomers
the clearest and most distant evidence that the theory still needs
some work. The gamma-ray emission originated about 70 light-years
away from the galaxy's central black hole.
The 4C +71.07 galaxy was discovered as a source of strong radio
emission in the 1960s. NASA's Compton Gamma-Ray Observatory, which
operated in the 1990s, detected high-energy flares, but the galaxy
was quiet during Fermi's first two and a half years in orbit.
In early November 2011, at the height of the outburst, the galaxy was
more than 10,000 times brighter than the combined luminosity of all
of the stars in our Milky Way galaxy.
"This renewed activity came after a long slumber, and that's important
because it allows us to explicitly link the gamma-ray flares to the
rising emission observed by radio telescopes," said David Thompson, a
Fermi deputy project scientist at NASA's Goddard Space Flight Center
in Greenbelt, Md.
Located in the constellation Ursa Major, 4C +71.07 is so far away that
its light takes 10.6 billion years to reach Earth. Astronomers are
seeing this galaxy as it existed when the universe was less than
one-fourth of its present age.
At the galaxy's core lies a supersized black hole weighing 2.6 billion
times the sun's mass. Some of the matter falling toward the black
hole becomes accelerated outward at almost the speed of light,
creating dual particle jets blasting in opposite directions. One jet
happens to point almost directly toward Earth. This characteristic
makes 4C +71.07 a blazar, a classification that includes some of the
brightest gamma-ray sources in the sky.
Boston University astronomers Alan Marscher and Svetlana Jorstad
routinely monitor 4C +71.07 along with dozens of other blazars using
several facilities, including the VLBA.
The instrument's 10 radio telescopes span North America, from Hawaii
to St. Croix in the U.S. Virgin Islands, and possess the resolving
power of a single radio dish more than 5,300 miles across when their
signals are combined. As a result, The VLBA resolves detail about a
million times smaller than Fermi's Large Area Telescope (LAT) and
1,000 times smaller than NASA's Hubble Space Telescope.
In autumn 2011, the VLBA images revealed a bright knot that appeared
to move outward at a speed 20 times faster than light.
"Although this apparent speed was an illusion caused by actual motion
almost directly toward us at 99.87 percent the speed of light, this
knot was the key to determining the location where the gamma-rays
were produced in the black hole's jet," said Marscher, who presented
the findings Monday at the American Astronomical Society meeting in
Long Beach, Calif.
The knot passed through a bright stationary feature of the jet, which
the astronomers refer to as its radio "core," on April 9, 2011. This
occurred within days of Fermi's detection of renewed gamma-ray
flaring in the blazar. Marscher and Jorstad noted that the blazar
brightened at visible wavelengths in step with the higher-energy
emission.
During the most intense period of flaring, from October 2011 to
January 2012, the scientists found the polarization direction of the
blazar's visible light rotated in the same manner as radio emissions
from the knot. They concluded the knot was responsible for the
visible and the gamma-ray light, which varied in sync.
This association allowed the researchers to pinpoint the location of
the gamma-ray outburst to about 70 light-years from the black hole.
The astronomers think that the gamma rays were produced when electrons
moving near the speed of light within the jet collided with visible
and infrared light originating outside of the jet. Such a collision
can kick the light up to much higher energies, a process known as
inverse-Compton scattering.
The source of the lower-energy light is unclear at the moment. The
researchers speculate the source may be an outer, slow-moving sheath
that surrounds the jet. Nicholas MacDonald, a graduate student at
Boston University, is investigating how the gamma-ray brightness
should change in this scenario to compare with observations.
"The VLBA is the only instrument that can bring us images from so near
the edge of a young supermassive black hole, and Fermi's LAT is the
only instrument that can see the highest-energy light from the
galaxy's jet," said Jorstad.
NASA's Fermi Gamma-ray Space Telescope is an astrophysics and particle
physics partnership. Fermi is managed by NASA's Goddard Space Flight
Center. It was developed in collaboration with the U.S. Department of
Energy, with contributions from academic institutions and partners in
France, Germany, Italy, Japan, Sweden and the United States.
Crackers in the deep space: Starbursts in the Milky Way
SOFIA SPOTS RECENT STARBURSTS IN THE MILKY WAY GALAXY'S CENTER
WASHINGTON -- Researchers using the Stratospheric Observatory for
Infrared Astronomy (SOFIA) have captured new images of a ring of gas
and dust seven light-years in diameter surrounding the supermassive
black hole at the center of the Milky Way, and of a neighboring
cluster of extremely luminous young stars embedded in dust cocoons.
The images of our galaxy's circumlunar ring (CNR) and its neighboring
quintuplet cluster (QC) are the subjects of two posters presented
this week during the American Astronomical Society's meeting in Long
Beach, Calif. Ryan Lau of Cornell University and his collaborators
studied the CNR. Matt Hankins of the University of Central Arkansas
in Conway is lead author of the other paper, regarding the QC.
SOFIA is a highly modified Boeing 747SP aircraft carrying a telescope
with an effective diameter of 100 inches (2.54 meters) to altitudes
as high as 45,000 feet (13.7 kilometers).
The images were obtained during SOFIA flights in 2011 with the Faint
Object Infrared Camera for the SOFIA Telescope (FORCAST) instrument
built by a team with principal investigator Terry Herter of Cornell.
FORCAST offered astronomers the ability to see the CNR and QC regions
and other exotic cosmic features whose light is obscured by water
vapor in Earth's atmosphere and interstellar dust clouds in the
mid-plane of the Milky Way. Neither ground-based observatories on
tall mountain peaks nor NASA's orbiting Hubble and Spitzer space
telescopes can see them.
WASHINGTON -- Researchers using the Stratospheric Observatory for
Infrared Astronomy (SOFIA) have captured new images of a ring of gas
and dust seven light-years in diameter surrounding the supermassive
black hole at the center of the Milky Way, and of a neighboring
cluster of extremely luminous young stars embedded in dust cocoons.
The images of our galaxy's circumlunar ring (CNR) and its neighboring
quintuplet cluster (QC) are the subjects of two posters presented
this week during the American Astronomical Society's meeting in Long
Beach, Calif. Ryan Lau of Cornell University and his collaborators
studied the CNR. Matt Hankins of the University of Central Arkansas
in Conway is lead author of the other paper, regarding the QC.
SOFIA is a highly modified Boeing 747SP aircraft carrying a telescope
with an effective diameter of 100 inches (2.54 meters) to altitudes
as high as 45,000 feet (13.7 kilometers).
The images were obtained during SOFIA flights in 2011 with the Faint
Object Infrared Camera for the SOFIA Telescope (FORCAST) instrument
built by a team with principal investigator Terry Herter of Cornell.
FORCAST offered astronomers the ability to see the CNR and QC regions
and other exotic cosmic features whose light is obscured by water
vapor in Earth's atmosphere and interstellar dust clouds in the
mid-plane of the Milky Way. Neither ground-based observatories on
tall mountain peaks nor NASA's orbiting Hubble and Spitzer space
telescopes can see them.
Weather mapping of the worlds unknown: Man gets insight of the stormy atmosphere of a brown dwarf
NASA TELESCOPES SEE WEATHER PATTERNS IN BROWN DWARF
WASHINGTON -- Astronomers using NASA's Spitzer and Hubble space
telescopes have probed the stormy atmosphere of a brown dwarf,
creating the most detailed "weather map" yet for this class of cool,
star-like orbs. The forecast shows wind-driven, planet-sized clouds
enshrouding these strange worlds.
Brown dwarfs form out of condensing gas, as stars do, but lack the
mass to fuse hydrogen atoms and produce energy. Instead, these
objects, which some call failed stars, are more similar to gas
planets with their complex, varied atmospheres. The new research is a
stepping stone toward a better understanding not only of brown
dwarfs, but also of the atmospheres of planets beyond our solar
system.
"With Hubble and Spitzer, we were able to look at different
atmospheric layers of a brown dwarf, similar to the way doctors use
medical imaging techniques to study the different tissues in your
body," said Daniel Apai, the principal investigator of the research
at the University of Arizona in Tucson, who presented the results at
the American Astronomical Society meeting Tuesday in Long Beach,
Calif.
A study describing the results, led by Esther Buenzli, also of the
University of Arizona, is published in the Astrophysical Journal
Letters.
The researchers turned Hubble and Spitzer simultaneously toward a
brown dwarf with the long name of 2MASSJ22282889-431026. They found
that its light varied in time, brightening and dimming about every 90
minutes as the body rotated. But more surprising, the team also found
the timing of this change in brightness depended on whether they
looked using different wavelengths of infrared light.
These variations are the result of different layers or patches of
material swirling around the brown dwarf in windy storms as large as
Earth itself. Spitzer and Hubble see different atmospheric layers
because certain infrared wavelengths are blocked by vapors of water
and methane high up, while other infrared wavelengths emerge from
much deeper layers.
"Unlike the water clouds of Earth or the ammonia clouds of Jupiter,
clouds on brown dwarfs are composed of hot grains of sand, liquid
drops of iron, and other exotic compounds," said Mark Marley,
research scientist at NASA's Ames Research Center in Moffett Field,
Calif., and co-author of the paper. "So this large atmospheric
disturbance found by Spitzer and Hubble gives a new meaning to the
concept of extreme weather."
According to Buenzli, this is the first time researchers can probe
variability at several different altitudes at the same time in the
atmosphere of a brown dwarf. "Although brown dwarfs are cool relative
to other stars, they are actually hot by earthly standards. This
particular object is about 1,100 to 1,300 degrees Fahrenheit (600 to
700 degrees Celsius)," Buenzli said.
"What we see here is evidence for massive, organized cloud systems,
perhaps akin to giant versions of the Great Red Spot on Jupiter,"
said Adam Showman, a theorist at the University of Arizona involved
in the research. "These out-of-sync light variations provide a
fingerprint of how the brown dwarf's weather systems stack up
vertically. The data suggest regions on the brown dwarf where the
weather is cloudy and rich in silicate vapor deep in the atmosphere
coincide with balmier, drier conditions at higher altitudes -- and
vice versa."
Researchers plan to look at the atmospheres of dozens of additional
nearby brown dwarfs using both Spitzer and Hubble.
"From studies such as this we will learn much about this important
class of objects, whose mass falls between that of stars and
Jupiter-sized planets." said Glenn Wahlgren, Spitzer Program
scientist at NASA Headquarters in Washington. "This technique will
see extensive use when we are able to image individual exoplanets."
WASHINGTON -- Astronomers using NASA's Spitzer and Hubble space
telescopes have probed the stormy atmosphere of a brown dwarf,
creating the most detailed "weather map" yet for this class of cool,
star-like orbs. The forecast shows wind-driven, planet-sized clouds
enshrouding these strange worlds.
Brown dwarfs form out of condensing gas, as stars do, but lack the
mass to fuse hydrogen atoms and produce energy. Instead, these
objects, which some call failed stars, are more similar to gas
planets with their complex, varied atmospheres. The new research is a
stepping stone toward a better understanding not only of brown
dwarfs, but also of the atmospheres of planets beyond our solar
system.
"With Hubble and Spitzer, we were able to look at different
atmospheric layers of a brown dwarf, similar to the way doctors use
medical imaging techniques to study the different tissues in your
body," said Daniel Apai, the principal investigator of the research
at the University of Arizona in Tucson, who presented the results at
the American Astronomical Society meeting Tuesday in Long Beach,
Calif.
A study describing the results, led by Esther Buenzli, also of the
University of Arizona, is published in the Astrophysical Journal
Letters.
The researchers turned Hubble and Spitzer simultaneously toward a
brown dwarf with the long name of 2MASSJ22282889-431026. They found
that its light varied in time, brightening and dimming about every 90
minutes as the body rotated. But more surprising, the team also found
the timing of this change in brightness depended on whether they
looked using different wavelengths of infrared light.
These variations are the result of different layers or patches of
material swirling around the brown dwarf in windy storms as large as
Earth itself. Spitzer and Hubble see different atmospheric layers
because certain infrared wavelengths are blocked by vapors of water
and methane high up, while other infrared wavelengths emerge from
much deeper layers.
"Unlike the water clouds of Earth or the ammonia clouds of Jupiter,
clouds on brown dwarfs are composed of hot grains of sand, liquid
drops of iron, and other exotic compounds," said Mark Marley,
research scientist at NASA's Ames Research Center in Moffett Field,
Calif., and co-author of the paper. "So this large atmospheric
disturbance found by Spitzer and Hubble gives a new meaning to the
concept of extreme weather."
According to Buenzli, this is the first time researchers can probe
variability at several different altitudes at the same time in the
atmosphere of a brown dwarf. "Although brown dwarfs are cool relative
to other stars, they are actually hot by earthly standards. This
particular object is about 1,100 to 1,300 degrees Fahrenheit (600 to
700 degrees Celsius)," Buenzli said.
"What we see here is evidence for massive, organized cloud systems,
perhaps akin to giant versions of the Great Red Spot on Jupiter,"
said Adam Showman, a theorist at the University of Arizona involved
in the research. "These out-of-sync light variations provide a
fingerprint of how the brown dwarf's weather systems stack up
vertically. The data suggest regions on the brown dwarf where the
weather is cloudy and rich in silicate vapor deep in the atmosphere
coincide with balmier, drier conditions at higher altitudes -- and
vice versa."
Researchers plan to look at the atmospheres of dozens of additional
nearby brown dwarfs using both Spitzer and Hubble.
"From studies such as this we will learn much about this important
class of objects, whose mass falls between that of stars and
Jupiter-sized planets." said Glenn Wahlgren, Spitzer Program
scientist at NASA Headquarters in Washington. "This technique will
see extensive use when we are able to image individual exoplanets."
Star Fomalhaut has a mysterious planet circling it
NASA'S HUBBLE REVEALS ROGUE PLANETARY ORBIT FOR FOMALHAUT
WASHINGTON -- Newly released NASA Hubble Space Telescope images of a
vast debris disk encircling the nearby star Fomalhaut and a
mysterious planet circling it may provide forensic evidence of a
titanic planetary disruption in the system.
Astronomers are surprised to find the debris belt is wider than
previously known, spanning a section of space from 14 to nearly 20
billion miles from the star. Even more surprisingly, the latest
Hubble images have allowed a team of astronomers to calculate the
planet follows an unusual elliptical orbit that carries it on a
potentially destructive path through the vast dust ring.
The planet, called Fomalhaut b, swings as close to its star as 4.6
billion miles, and the outermost point of its orbit is 27 billion
miles away from the star. The orbit was recalculated from the newest
Hubble observation made last year.
"We are shocked. This is not what we expected," said Paul Kalas of the
University of California at Berkeley and the SETI Institute in
Mountain View, Calif.
The Fomalhaut team led by Kalas considers this circumstantial evidence
there may be other planet-like bodies in the system that
gravitationally disturbed Fomalhaut b to place it in such a highly
eccentric orbit. The team presented its finding Tuesday at the 221st
meeting of the American Astronomical Society in Long Beach, Calif.
Among several scenarios to explain Fomalhaut b's 2,000-year-long orbit
is the hypothesis that an as yet undiscovered planet gravitationally
ejected Fomalhaut b from a position closer to the star, and sent it
flying in an orbit that extends beyond the dust belt.
"Hot Jupiters get tossed through scattering events, where one planet
goes in and one gets thrown out," said co-investigator Mark Clampin
of NASA's Goddard Space Flight Center in Greenbelt, Md. "This could
be the planet that gets thrown out."
Hubble also found the dust and ice belt encircling the star Fomalhaut
has an apparent gap slicing across the belt. This might have been
carved by another undetected planet. Hubble's exquisite view of the
dust belt shows irregularities that strongly motivate a search for
other planets in the system.
If its orbit lies in the same plane with the dust belt, then Fomalhaut
b will intersect the belt around 2032 on the outbound leg of its
orbit. During the crossing, icy and rocky debris in the belt could
crash into the planet's atmosphere and create the type of cosmic
fireworks seen when Comet Shoemaker-Levy 9 crashed into Jupiter. Most
of the fireworks from collisions will be seen in infrared light.
However, if Fomalhaut b is not co-planar with the belt, the only
thing to be seen will be a gradual dimming of Fomalhaut b as it
travels farther from the star.
Kalas hypothesized that Fomalhaut b's extreme orbit is a major clue in
explaining why the planet is unusually bright in visible light, but
very dim in infrared light. It is possible the planet's optical
brightness originates from a ring or shroud of dust around the
planet, which reflects starlight. The dust would be rapidly produced
by satellites orbiting the planet, which would suffer extreme erosion
by impacts and gravitational stirring when Fomalhaut b enters into
the planetary system after a millennium of deep freeze beyond the
main belt. An analogy can be found by looking at Saturn, which has a
tenuous, but very large dust ring produced when meteoroids hit the
outer moon Phoebe.
The team has also considered a different scenario where a hypothetical
second dwarf planet suffered a catastrophic collision with Fomalhaut
b. The collision scenario would explain why the star Fomalhaut has a
narrow outer belt linked to an extreme planet. But in this case the
belt is young, less than 10,000 years old, and it is difficult to
produce energetic collisions far from the star in such young systems.
Fomalhaut is a special system because it looks like scientists may
have a snapshot of what our solar system was doing 4 billion years
ago. The planetary architecture is being redrawn, the comet belts are
evolving, and planets may be gaining and losing their moons.
Astronomers will continue monitoring Fomalhaut b for decades to come
because they may have a chance to observe a planet entering an icy
debris belt that is like the Kuiper Belt at the fringe of our own
solar system.
WASHINGTON -- Newly released NASA Hubble Space Telescope images of a
vast debris disk encircling the nearby star Fomalhaut and a
mysterious planet circling it may provide forensic evidence of a
titanic planetary disruption in the system.
Astronomers are surprised to find the debris belt is wider than
previously known, spanning a section of space from 14 to nearly 20
billion miles from the star. Even more surprisingly, the latest
Hubble images have allowed a team of astronomers to calculate the
planet follows an unusual elliptical orbit that carries it on a
potentially destructive path through the vast dust ring.
The planet, called Fomalhaut b, swings as close to its star as 4.6
billion miles, and the outermost point of its orbit is 27 billion
miles away from the star. The orbit was recalculated from the newest
Hubble observation made last year.
"We are shocked. This is not what we expected," said Paul Kalas of the
University of California at Berkeley and the SETI Institute in
Mountain View, Calif.
The Fomalhaut team led by Kalas considers this circumstantial evidence
there may be other planet-like bodies in the system that
gravitationally disturbed Fomalhaut b to place it in such a highly
eccentric orbit. The team presented its finding Tuesday at the 221st
meeting of the American Astronomical Society in Long Beach, Calif.
Among several scenarios to explain Fomalhaut b's 2,000-year-long orbit
is the hypothesis that an as yet undiscovered planet gravitationally
ejected Fomalhaut b from a position closer to the star, and sent it
flying in an orbit that extends beyond the dust belt.
"Hot Jupiters get tossed through scattering events, where one planet
goes in and one gets thrown out," said co-investigator Mark Clampin
of NASA's Goddard Space Flight Center in Greenbelt, Md. "This could
be the planet that gets thrown out."
Hubble also found the dust and ice belt encircling the star Fomalhaut
has an apparent gap slicing across the belt. This might have been
carved by another undetected planet. Hubble's exquisite view of the
dust belt shows irregularities that strongly motivate a search for
other planets in the system.
If its orbit lies in the same plane with the dust belt, then Fomalhaut
b will intersect the belt around 2032 on the outbound leg of its
orbit. During the crossing, icy and rocky debris in the belt could
crash into the planet's atmosphere and create the type of cosmic
fireworks seen when Comet Shoemaker-Levy 9 crashed into Jupiter. Most
of the fireworks from collisions will be seen in infrared light.
However, if Fomalhaut b is not co-planar with the belt, the only
thing to be seen will be a gradual dimming of Fomalhaut b as it
travels farther from the star.
Kalas hypothesized that Fomalhaut b's extreme orbit is a major clue in
explaining why the planet is unusually bright in visible light, but
very dim in infrared light. It is possible the planet's optical
brightness originates from a ring or shroud of dust around the
planet, which reflects starlight. The dust would be rapidly produced
by satellites orbiting the planet, which would suffer extreme erosion
by impacts and gravitational stirring when Fomalhaut b enters into
the planetary system after a millennium of deep freeze beyond the
main belt. An analogy can be found by looking at Saturn, which has a
tenuous, but very large dust ring produced when meteoroids hit the
outer moon Phoebe.
The team has also considered a different scenario where a hypothetical
second dwarf planet suffered a catastrophic collision with Fomalhaut
b. The collision scenario would explain why the star Fomalhaut has a
narrow outer belt linked to an extreme planet. But in this case the
belt is young, less than 10,000 years old, and it is difficult to
produce energetic collisions far from the star in such young systems.
Fomalhaut is a special system because it looks like scientists may
have a snapshot of what our solar system was doing 4 billion years
ago. The planetary architecture is being redrawn, the comet belts are
evolving, and planets may be gaining and losing their moons.
Astronomers will continue monitoring Fomalhaut b for decades to come
because they may have a chance to observe a planet entering an icy
debris belt that is like the Kuiper Belt at the fringe of our own
solar system.
Star Vega: This second brightest star in northern night skies too has an asteroid belt around it
2013
WASHINGTON -- Astronomers have discovered what appears to be a large
asteroid belt around the star Vega, the second brightest star in
northern night skies. The scientists used data from NASA's Spitzer
Space Telescope and the European Space Agency's (ESA) Herschel Space
Observatory, in which NASA plays an important role.
The discovery of an asteroid belt-like band of debris around Vega
makes the star similar to another observed star called Fomalhaut. The
data are consistent with both stars having inner, warm belts and
outer, cool belts separated by a gap. This architecture is similar to
the asteroid and Kuiper belts in our own solar system.
What is maintaining the gap between the warm and cool belts around
Vega and Fomalhaut? The results strongly suggest the answer is
multiple planets. Our solar system's asteroid belt, which lies
between Mars and Jupiter, is maintained by the gravity of the
terrestrial planets and the giant planets, and the outer Kuiper belt
is sculpted by the giant planets.
"Our findings echo recent results showing multiple-planet systems are
common beyond our sun," said Kate Su, an astronomer at the Steward
Observatory at the University of Arizona. Su presented the results
Tuesday at the American Astronomical Society meeting in Long Beach,
Calif., and is lead author of a paper on the findings accepted for
publication in the Astrophysical Journal.
Vega and Fomalhaut are similar in other ways. Both are about twice the
mass of our sun and burn a hotter, bluer color in visible light. Both
stars are relatively nearby at about 25 light-years away. The stars
are thought to be around 400 million years old, but Vega could be
closer to its 600 millionth birthday. Fomalhaut has a single
candidate planet orbiting it, Fomalhaut b, which orbits at the inner
edge of its cometary belt.
The Herschel and Spitzer telescopes detected infrared light emitted by
warm and cold dust in discrete bands around Vega and Fomalhaut,
discovering the new asteroid belt around Vega and confirming the
existence of the other belts around both stars. Comets and the
collisions of rocky chunks replenish the dust in these bands. The
inner belts in these systems cannot be seen in visible light because
the glare of their stars outshines them.
Both the inner and outer belts contain far more material than our own
asteroid and Kuiper belts. The reason is twofold: the star systems
are far younger than our own, which has had hundreds of millions more
years to clean house, and the systems likely formed from an initially
more massive cloud of gas and dust than our solar system.
The gap between the inner and outer debris belts for Vega and
Fomalhaut also proportionally corresponds to the distance between our
sun's asteroid and Kuiper belts. This distance works out to a ratio
of about 1:10, with the outer belt 10 times farther away from its
host star than the inner belt. As for the large gap between the two
belts, it is likely there are several undetected planets,
Jupiter-sized or smaller, creating a dust-free zone between the two
belts. A good comparison star system is HR 8799, which has four known
planets that sweep up the space between two similar disks of debris.
"Overall, the large gap between the warm and the cold belts is a
signpost that points to multiple planets likely orbiting around Vega
and Fomalhaut," said Su.
If unseen planets do in fact orbit Vega and Fomalhaut, these bodies
will not likely stay hidden.
"Upcoming new facilities such as NASA's James Webb Space Telescope
should be able to find the planets," said paper co-author Karl
Stapelfeldt, chief of the Exoplanets and Stellar Astrophysics
Laboratory at NASA's Goddard Space Flight Center in Greenbelt, Md.
Saturday, January 5, 2013
All about the Red Planet Mars: Yet another meteorite contains water
2013
WASHINGTON -- NASA-funded researchers analyzing a small meteorite that
may be the first discovered from the Martian surface or crust have
found it contains 10 times more water than other Martian meteorites
from unknown origins.
This new class of meteorite was found in 2011 in the Sahara Desert.
Designated Northwest Africa (NWA) 7034, and nicknamed "Black Beauty,"
it weighs approximately 11 ounces (320 grams). After more than a year
of intensive study, a team of U.S. scientists determined the
meteorite formed 2.1 billion years ago during the beginning of the
most recent geologic period on Mars, known as the Amazonian.
"The age of NWA 7034 is important because it is significantly older
than most other Martian meteorites," said Mitch Schulte, program
scientist for the Mars Exploration Program at NASA Headquarters in
Washington. "We now have insight into a piece of Mars' history at a
critical time in its evolution."
The meteorite is an excellent match for surface rocks and outcrops
NASA has studied remotely via Mars rovers and Mars-orbiting
satellites. NWA 7034's composition is different from any previously
studied Martian meteorite. The research is published in Thursday's
edition of Science Express.
"The contents of this meteorite may challenge many long held notions
about Martian geology," said John Grunsfeld, associate administrator
for NASA's Science Mission Directorate in Washington. "These findings
also present an important reference frame for the Curiosity rover as
it searches for reduced organics in the minerals exposed in the
bedrock of Gale Crater."
NWA 7034 is made of cemented fragments of basalt, rock that forms from
rapidly cooled lava. The fragments are primarily feldspar and
pyroxene, most likely from volcanic activity. This unusual
meteorite's chemistry matches that of the Martian crust as measured
by NASA's Mars Exploration Rovers and Mars Odyssey Orbiter.
"This Martian meteorite has everything in its composition that you'd
want in order to further our understanding of the Red Planet," said
Carl Agee, leader of the analysis team and director and curator at
the University of New Mexico's Institute of Meteoritics in
Albuquerque. "This unique meteorite tells us what volcanism was like
on Mars 2 billion years ago. It also gives us a glimpse of ancient
surface and environmental conditions on Mars that no other meteorite
has ever offered."
The research team included groups at the University of California at
San Diego and the Carnegie Institution in Washington. Experiments
were conducted to analyze mineral and chemical composition, age, and
water content.
Researchers theorize the large amount of water contained in NWA 7034
may have originated from interaction of the rocks with water present
in Mars' crust. The meteorite also has a different mixture of oxygen
isotopes than has been found in other Martian meteorites, which could
have resulted from interaction with the Martian atmosphere.
Most Martian meteorites are divided into three rock types, named after
three meteorites; Shergotty, Nakhla, and Chassigny. These "SNC"
meteorites currently number about 110. Their point of origin on Mars
is not known and recent data from lander and orbiter missions suggest
they are a mismatch for the Martian crust. Although NWA 7034 has
similarities to the SNC meteorites, including the presence of
macromolecular organic carbon, this new meteorite has many unique
characteristics.
"The texture of the NWA meteorite is not like any of the SNC
meteorites," said co-author Andrew Steele, who led the carbon
analysis at the Carnegie Institution's Geophysical Laboratory. "This
is an exciting measurement in Mars and planetary science. We now have
more context than ever before to understanding where they may come
from."
The research was funded by NASA's Cosmochemistry Program and
Astrobiology Institute, part of the Planetary Science Division in the
Science Mission Directorate at NASA Headquarters. The research also
was supported by the New Mexico Space Grant Consortium in Las Cruces,
and the National Science Foundation in Arlington, Va.
Tuesday, January 1, 2013
Dog flu and bird flu similarities: The first systematic surveillance of H3N2 canine influenza virus (CIV) in various dog populations in southern China revealed that the viruses were similar to recently isolated avian-origin strains in dogs and cats from Korea and elsewhere in China
2012
The first systematic surveillance of H3N2 canine influenza virus (CIV) in various dog populations in southern China revealed that the viruses were similar to recently isolated avian-origin strains in dogs and cats from Korea and elsewhere in China.
The researchers based their findings on canine nasal samples taken from dog farms in Guangzhou and Shenzen and from pet dogs.
They reported their findings in the Dec 20 issue of Infection, Genetics and Evolution. Serologic surveillance revealed that the infection rates for avian-origin H3N2 in farmed and pet dogs were 12.22% and 5.3%, respectively.
The authors suggested that the virus probably spread via close contact between infected dogs in different dog populations.
The group warned that virus circulation in a densely populated area with heavy animal trade poses a risk for pets and provides an environment for mutations and reassortment that could lead to new virus strains and possible threats to public health.
Sirturo (bedaquiline) for multidrug-resistant tuberculosis: The US Food and Drug Administration (FDA) approves Sirturo (bedaquiline), the first drug developed specifically to treat multidrug-resistant tuberculosis (MDR-TB), saying it must be used in combination with other TB medications
FDA approves first med for multidrug-resistant TB
Robert Roos 
News Editor
News EditorThe drug, developed by Jannsen Therapeutics, Titusville, N.J., inhibits an enzyme that Mycobacterium tuberculosis uses to replicate and spread, the FDA said in a news release. Janssen officials said it is the first TB drug in 40 years that has a new mechanism of action.
MDR-TB strains are those that resist isoniazid and rifampin, the two drugs most commonly used to treat TB patients, the FDA noted.
"Multi-drug resistant tuberculosis poses a serious health threat throughout the world, and Sirturo provides much-needed treatment for patients who don't have other therapeutic options available," said Edward Cox, MD, MPH, in the FDA release. He is director of the Office of Antimicrobial Products in the FDA's Center for Drug Evaluation and Research.
But he warned that the drug carries significant risks, including heart arrhythmias, and therefore must be used carefully and limited to patients who lack other treatment options.
About 310,000 cases of MDR-TB were identified among reported pulmonary TB patients in 2011, according to the World Health Organization. In the United States, MDR-TB is considered an orphan disease, with 98 patients reported in 2011, according to a Janssen press release.
The FDA said it endorsed Sirturo under its accelerated approval program, which allows the agency to approve a drug on the basis of a demonstrated effect on a surrogate end point that is reasonably likely to predict a clinical benefit to patients. The program speeds the availability of new drugs while requiring companies to conduct more studies of their benefits and safety.
The FDA also granted Sirturo fast-track status, priority review, and orphan-product designation. The drug showed the potential to fill an unmet medical need, has the potential to provide safe and effective treatment where no other satisfactory therapy exists, and is intended to treat a rare disease, the agency said.
Sirturo's safety and effectiveness were established in two phase 2 clinical trials involving 440 patients, the FDA reported. The surrogate end point used in the studies was the time it took for patients' sputum to be clear of M tuberculosis (sputum culture conversion).
Patients in the first trial were randomly assigned to be treated either with Sirturo plus other TB drugs or with a placebo and other TB drugs. Patients in the Sirturo group had a median sputum conversion time of 83 days, versus 125 days for the placebo group.
In the second trial, which is ongoing, all patients received Sirturo plus other TB drugs. Results so far have shown a median time to sputum conversion of 57 days, supporting the efficacy findings of the first trial, the FDA said.
Common side effects identified in the clinical trials include nausea, joint pain, and headache, the agency noted.
The FDA and Janssen said Sirturo carries a boxed warning that the drug can affect the heart's electrical activity by prolonging the QT interval, which could lead to an abnormal and potentially fatal heart rhythm.
The warning also says that in the placebo-controlled trial, 9 of 79 patients (11.4%) in the treatment group died, compared with 2 of 81 (2.5%) in the placebo group.
"Five of the deaths in the Sirturo group and all of the deaths in the placebo arm seemed to be related to tuberculosis, but no consistent reason for the deaths in the remaining Sirturo-treated patients could be identified," the FDA said.
The Janssen statement said Sirturo inhibits mycobacterial adenosine 5'-triphosphate, an essential enzyme for generating energy in M tuberculosis. The drug was discovered more than a decade ago, said Paul Stoffels, MD, chief scientific officer and worldwide pharmaceuticals chairman at Johnson & Johnson, Janssen's parent company.
ICRISAT’s genebank, one of the world’s largest public-funded genebanks, preserves seeds of more than 120,000 accessions of pearl millet, sorghum, chickpea, pigeonpea, groundnut and small millets (finger millet, foxtail millet, barnyard millet, kodo millet, and little millet)
Olympic medalist lauds ICRISAT’s gene conservation efforts in the fight against hunger and poverty
Hyderabad: Dec 30: “ICRISAT’s plant genetic conservation initiatives illustrate the value and use of crop biodiversity in the fight against hunger and poverty, and its impact on the livelihoods of millions of smallholder farmers in the dryland tropics,” said India’s ace badminton player and Olympic bronze medalist Ms Saina Nehwal.
During her visit to the Hyderabad-based International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) today, Ms Nehwal described her experience touring the Institute’s facilities, particularly its RS Paroda Genebank, as delightful and an eye-opener.
“Nature has truly blessed us with a rich genetic diversity, which is unique and important in sustaining life in this planet. This visit gave me a better understanding of the importance of plant genetic conservation in sustaining and using genetic diversity for global food security,” Ms Newhal added.
“ICRISAT’s RS Paroda Genebank is a treasure trove of genes useful to crop improvement for sustainable food production and improved livelihoods, particularly in marginal environments, and genes that can provide climate resilience to future crop varieties through increased drought, heat and salinity tolerance, and pest and disease resistance, said ICRISAT Director General William D. Dar.
ICRISAT has been conducting research-for-development initiatives with partners globally for the past 40 years to increase agricultural production in the semi-arid regions of Asia and sub-Saharan Africa.
ICRISAT’s genebank, one of the world’s largest public-funded genebanks, preserves seeds of more than 120,000 accessions of pearl millet, sorghum, chickpea, pigeonpea, groundnut and small millets (finger millet, foxtail millet, barnyard millet, kodo millet, and little millet), that are kept as in-trust collections on behalf of the Food and Agriculture Organization (FAO) of the United Nations (UN), for the benefit of the present and future generations.
It has also distributed more than 1.4 million seed samples to 146 countries, restored about 55,000 germplasm lines to 9 countries, and released 830 cultivars in 79 countries from its germplasm and breeding materials.
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