1,408 research outputs found
Dependence of Deodorant Usage on ABCC11 Genotype:Scope for Personalized Genetics in Personal Hygiene
Earwax type and axillary odor are genetically determined by rs17822931, a single-nucleotide polymorphism (SNP) located in the ABCC11 gene. The literature has been concerned with the Mendelian trait of earwax, although axillary odor is also Mendelian. Ethnic diversity in rs17822931 exists, with higher frequency of allele A in east Asians. Influence on deodorant usage has not been investigated. In this work, we present a detailed analysis of the rs17822931 effect on deodorant usage in a large (N∼17,000 individuals) population cohort (the Avon Longitudinal Study of Parents and Children (ALSPAC)). We found strong evidence (P=3.7 × 10(−20)) indicating differential deodorant usage according to the rs17822931 genotype. AA homozygotes were almost 5-fold overrepresented in categories of never using deodorant or using it infrequently. However, 77.8% of white European genotypically nonodorous individuals still used deodorant, and 4.7% genotypically odorous individuals did not. We provide evidence of a behavioral effect associated with rs17822931. This effect has a biological basis that can result in a change in the family's environment if an aerosol deodorant is used. It also indicates potential cost saving to the nonodorous and scope for personalized genetics usage in personal hygiene choices, with consequent reduction of inappropriate chemical exposures for some
Non-BPS Brane Cosmology
We study cosmology on a BPS D3-brane evolving in the 10D SUGRA background
describing a non-BPS brane. Initially the BPS brane is taken to be a probe
whose dynamics we determine in the non-compact non-BPS background. The
cosmology observed on the brane is of the FRW type with a scale factor
. In this mirage cosmology approach, there is no self-gravity on the
brane which cannot inflate. Self-gravity is then included by compactifying the
background space-time. The low energy effective theory below the
compactification scale is shown to be bi-metric, with matter coupling to a
different metric than the geometrically induced metric on the brane. The
geometrical scale factor on the brane is now where
arises from brane self-gravity. In this non-BPS scenario the brane generically
inflates. We study the resulting inflationary scenario taking into account the
fact that the non-BPS brane eventually decays on a time-scale much larger than
the typical inflationary time-scale. After the decay, the theory ceases to be
bi-metric and COBE normalization is used to estimate the string scale which is
found to be of order GeV.Comment: 20 pages, JHEP3.cl
High-Resolution, Wide-Field Imaging of the Galactic Center Region at 330 MHz
We present a wide field, sub-arcminute resolution VLA image of the Galactic
Center region at 330 MHz. With a resolution of ~ 7" X 12" and an RMS noise of
1.6 mJy/beam, this image represents a significant increase in resolution and
sensitivity over the previously published VLA image at this frequency. The
improved sensitivity has more than tripled the census of small diameter sources
in the region, has resulted in the detection of two new Non Thermal Filaments
(NTFs), 18 NTF candidates, 30 pulsar candidates, reveals previously known
extended sources in greater detail, and has resulted in the first detection of
Sagittarius A* in this frequency range.
A version of this paper containing full resolution images may be found at
http://lwa.nrl.navy.mil/nord/AAAB.pdf.Comment: Astronomical Journal, Accepted 62 Pages, 21 Figure
MERLIN/VLA imaging of the gravitational lens system B0218+357
Gravitational lenses offer the possibility of accurately determining the
Hubble parameter (H_0) over cosmological distances, and B0218+357 is one of the
most promising systems for an application of this technique. In particular this
system has an accurately measured time delay (10.5+/-0.4 d; Biggs et al. 1999)
and preliminary mass modelling has given a value for H_0 of 69 +13/-19
km/s/Mpc. The error on this estimate is now dominated by the uncertainty in the
mass modelling. As this system contains an Einstein ring it should be possible
to constrain the model better by imaging the ring at high resolution. To
achieve this we have combined data from MERLIN and the VLA at a frequency of 5
GHz. In particular MERLIN has been used in multi-frequency mode in order to
improve substantially the aperture coverage of the combined data set. The
resulting map is the best that has been made of the ring and contains many new
and interesting features. Efforts are currently underway to exploit the new
data for lensing constraints using the LensClean algorithm (Kochanek & Narayan
1992).Comment: Accepted for publication in MNRAS. 6 pages, 4 included PostScript
figure
Defining “Science-based Targets”
The term “science-based targets” has gained recent popularity. It is used to refer both to overall science-based targets (established through intergovernmental treaties), and to their disaggregation into specific science-based targets (determining contributions of individual actors). Biophysical achievability, measurability, and underpinning rationale are requirements for considering a target to be “science-based”
Intersublevel Polaron Dephasing in Self-Assembled Quantum Dots
Polaron dephasing processes are investigated in InAs/GaAs dots using
far-infrared transient four wave mixing (FWM) spectroscopy. We observe an
oscillatory behaviour in the FWM signal shortly (< 5 ps) after resonant
excitation of the lowest energy conduction band transition due to coherent
acoustic phonon generation. The subsequent single exponential decay yields long
intraband dephasing times of 90 ps. We find excellent agreement between our
measured and calculated FWM dynamics, and show that both real and virtual
acoustic phonon processes are necessary to explain the temperature dependence
of the polarization decay.Comment: 10 pages, 4 figures, submitted to Phys Rev Let
PKS B1545-321: Bow shocks of a relativistic jet?
Sensitive, high resolution images of the double-double radio galaxy PKS
B1545-321 reveal detailed structure, which we interpret in the light of
previous work on the interaction of restarted jets with pre-existing relict
cocoons. We have also examined the spectral and polarization properties of the
source, the color distribution in the optical host and the environment of this
galaxy in order to understand its physical evolution. We propose that the
restarted jets generate narrow bow shocks and that the inner lobes are a
mixture of cocoon plasma reaccelerated at the bow shock and new jet material
reaccelerated at the termination shock. The dynamics of the restarted jets
implies that their hot spots advance at mildly relativistic speeds with
external Mach numbers of at least 5. The existence of supersonic hot spot Mach
numbers and bright inner lobes is the result of entrainment causing a reduction
in the sound speed of the pre-existing cocoon. The interruption to jet activity
in PKS B1545-321 has been brief - lasting less than a few percent of the
lifetime of the giant radio source. The host
galaxy is located at the boundary of a large scale filamentary structure, and
shows blue patches in color distribution indicative of a recent merger, which
may have triggered the Mpc-scale radio galaxy.Comment: 26 pages including 1 table and 16 figures. To appear in MNRA
An Automated Method for the Detection and Extraction of HI Self-Absorption in High-Resolution 21cm Line Surveys
We describe algorithms that detect 21cm line HI self-absorption (HISA) in
large data sets and extract it for analysis. Our search method identifies HISA
as spatially and spectrally confined dark HI features that appear as negative
residuals after removing larger-scale emission components with a modified CLEAN
algorithm. Adjacent HISA volume-pixels (voxels) are grouped into features in
(l,b,v) space, and the HI brightness of voxels outside the 3-D feature
boundaries is smoothly interpolated to estimate the absorption amplitude and
the unabsorbed HI emission brightness. The reliability and completeness of our
HISA detection scheme have been tested extensively with model data. We detect
most features over a wide range of sizes, linewidths, amplitudes, and
background levels, with poor detection only where the absorption brightness
temperature amplitude is weak, the absorption scale approaches that of the
correlated noise, or the background level is too faint for HISA to be
distinguished reliably from emission gaps. False detection rates are very low
in all parts of the parameter space except at sizes and amplitudes approaching
those of noise fluctuations. Absorption measurement biases introduced by the
method are generally small and appear to arise from cases of incomplete HISA
detection. This paper is the third in a series examining HISA at high angular
resolution. A companion paper (Paper II) uses our HISA search and extraction
method to investigate the cold atomic gas distribution in the Canadian Galactic
Plane Survey.Comment: 39 pages, including 14 figure pages; to appear in June 10 ApJ, volume
626; figure quality significantly reduced for astro-ph; for full resolution,
please see http://www.ras.ucalgary.ca/~gibson/hisa/cgps1_survey
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