155 research outputs found
Observations of the Prompt Gamma-Ray Emission of GRB 070125
The long, bright gamma-ray burst GRB 070125 was localized by the
Interplanetary Network. We present light curves of the prompt gamma-ray
emission as observed by Konus-WIND, RHESSI, Suzaku-WAM, and \textit{Swift}-BAT.
We detail the results of joint spectral fits with Konus and RHESSI data. The
burst shows moderate hard-to-soft evolution in its multi-peaked emission over a
period of about one minute. The total burst fluence as observed by Konus is
erg/cm (20 keV--10 MeV). Using the spectroscopic
redshift , we find that the burst is consistent with the ``Amati''
correlation. Assuming a jet opening angle derived from
broadband modeling of the burst afterglow, GRB 070125 is a significant outlier
to the ``Ghirlanda'' correlation. Its
collimation-corrected energy release ergs is
the largest yet observed.Comment: 25 pages, 6 figures; accepted for publication in ApJ. Improved
spectral fits and energetics estimate
Detailed insights into pan-European population structure and inbreeding in wild and hatchery Pacific oysters (Crassostrea gigas) revealed by genome-wide SNP data.
Cultivated bivalves are important not only because of their economic value, but also due to their impacts on natural ecosystems. The Pacific oyster (Crassostrea gigas) is the world's most heavily cultivated shellfish species and has been introduced to all continents except Antarctica for aquaculture. We therefore used a medium-density single nucleotide polymorphism (SNP) array to investigate the genetic structure of this species in Europe, where it was introduced during the 1960s and has since become a prolific invader of coastal ecosystems across the continent. We analyzed 21,499 polymorphic SNPs in 232 individuals from 23 localities spanning a latitudinal cline from Portugal to Norway and including the source populations of Japan and Canada. We confirmed the results of previous studies by finding clear support for a southern and a northern group, with the former being indistinguishable from the source populations indicating the absence of a pronounced founder effect. We furthermore conducted a large-scale comparison of oysters sampled from the wild and from hatcheries to reveal substantial genetic differences including significantly higher levels of inbreeding in some but not all of the sampled hatchery cohorts. These findings were confirmed by a smaller but representative SNP dataset generated using restriction site-associated DNA sequencing. We therefore conclude that genomic approaches can generate increasingly detailed insights into the genetics of wild and hatchery produced Pacific oysters
Emergence of Delayed Methylmercury Toxicity after Perinatal Exposure in Metallothionein-Null and Wild-Type C57BL Mice
ALMA twenty-six arcmin survey of GOODS-S at one-millimeter (ASAGAO): Near-infrared-dark faint ALMA sources
We report detections of two 1.2 mm continuum sources ( ~
0.6 mJy) without any counterparts in the deep - and/or -band image (i.e.,
-band magnitude 26 mag). These near-infrared-dark faint millimeter
sources are uncovered by ASAGAO, a deep and wide-field ( 26 arcmin)
Atacama Large Millimeter/submillimeter Array (ALMA) 1.2 mm survey. One has a
red IRAC (3.6 and 4.5 m) counterpart, and the other has been independently
detected at 850 and 870 m using SCUBA2 and ALMA Band 7, respectively.
Their optical to radio spectral energy distributions indicate that they can lie
at 3-5 and can be in the early phase of massive galaxy formation.
Their contribution to the cosmic star formation rate density is estimated to be
~ 1 10 yr Mpc if they lie somewhere in
the redshift range of ~ 3-5. This value can be consistent with, or greater
than that of bright submillimeter galaxies ( 4.2 mJy) at
~ 3-5. We also uncover 3 more candidates near-infrared-dark faint ALMA
sources without any counterparts ( ~ 0.45-0.86 mJy). These
results show that an unbiased ALMA survey can reveal the dust-obscured star
formation activities, which were missed in previous deep optical/near-infrared
surveys.Comment: 10 pages, 6 figures, accepted for publication in Ap
Alma Twenty-six Arcmin^2 Survey Of Goods-s At One-millimeter (asagao): Source Catalog And Number Counts
We present the survey design, data reduction, construction of images, and
source catalog of the Atacama Large Millimeter/submillimeter Array (ALMA)
twenty-six arcmin^2 survey of GOODS-S at one-millimeter (ASAGAO). ASAGAO is a
deep (1sigma ~ 61 uJy/beam for a 250 klambda-tapered map with a synthesized
beam size of 0.51" x 0.45") and wide area (26 arcmin^2) survey on a contiguous
field at 1.2 mm. By combining with ALMA archival data in the GOODS-South field,
we obtained a deeper map in the same region (1sigma ~ 30 uJy/beam for a deep
region with a 250 klambda-taper, and a synthesized beam size of 0.59" x 0.53"),
providing the largest sample of sources (25 sources at >=5.0sigma, 45 sources
at >=4.5sigma) among ALMA blank-field surveys to date. The number counts shows
that 52(+11 -8)% of the extragalactic background light at 1.2 mm is resolved
into discrete sources at S1.2m > 135 uJy. We create infrared (IR) luminosity
functions (LFs) in the redshift range of z = 1-3 from the ASAGAO sources with
KS-band counterparts, and constrain the faintest luminosity of the LF at 2.0 <
z < 3.0. The LFs are consistent with previous results based on other ALMA and
SCUBA-2 observations, which suggest a positive luminosity evolution and
negative density evolution with increasing redshift. We find that obscured
star-formation of sources with IR luminosities of log(L(IR)/Lsun)} ~> 11.8
account for ~~60%-90% of the z ~ 2 cosmic star-formation rate density.Comment: 19 pages, 18 figures, accepted for publication in PAS
Sex differences in self-construal and in depressive symptoms: predictors of cross-national variation
Sex differences in aspects of independent versus interdependent self-construal and depressive symptoms were surveyed among 5,320 students from 24 nations. Men were found to perceive themselves as more self-contained whereas women perceived themselves as more connected to others. No significant sex differences were found on two further dimensions of self-construal, or on a measure of depressive symptoms. Multilevel modeling was used to test the ability of a series of predictors derived from a social identity perspective and from evolutionary theory to moderate sex differences. Contrary to most prior studies of personality, sex differences in self-construal were larger in samples from nations scoring lower on the Gender Gap Index, and the Human Development Index. Sex differences were also greater in nations with higher pathogen prevalence, higher self-reported religiosity, and in nations with high reported avoidance of settings with strong norms. The findings are discussed in terms of the interrelatedness of self-construals and the cultural contexts in which they are elicited and the distinctiveness of student samples
Digital Pheromone Implementation of PSO with Velocity Vector Accelerated by Commodity Graphics Hardware
In this paper, a model for Graphics Processing Unit (GPU) implementation of Particle Swarm Optimization (PSO) using digital pheromones to coordinate swarms within ndimensional design spaces is presented. Particularly, the velocity vector computations are carried out on graphics hardware. Previous work by the authors demonstrated the capability of digital pheromones within PSO for searching n-dimensional design spaces with improved accuracy, efficiency and reliability in serial, parallel and GPU computing environments. The GPU implementation was limited to computing the objective function values alone. Modern GPUs have proven to outperform the number of floating point operations when compared to CPUs through inherent data parallel architecture and higher bandwidth capabilities. This paper presents a method to implement velocity vector computations on a GPU along with objective function evaluations. Three different modes of implementation are studied and presented - First, CPU-CPU where objective function and velocity vector are calculated on CPU alone. Second, GPU-CPU where objective function is computed on the GPU and velocity vector is computed on GPU. Third, GPU-GPU where objective function and velocity vector are both evaluated on the GPU. The results from these three implementations are presented followed by conclusions and recommendations on the best approach for utilizing the full potential of GPUs for PSO
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