5,797 research outputs found
Nondestructive Evaluation of Hardwood Logs Using Automated Interpretation of CT Images
Knowledge of internal defects within hardwood logs can be useful even prior to a log’s entry into the sawmill. It is in the log yard where the first important decisions are made about processing. First, based upon perceived quality, logs may be sorted as veneer logs or as high-quality sawlogs and sold to domestic veneer mills or for export. Second, roundwood may be bucked into smaller logs to isolate defect areas and to obtain sawlogs with longer sections of clear wood. And third, logs containing metal objects can be identified, thereby preventing headrig saw damage and costly mill down-time
Analysis of Archived Residual Newborn Screening Blood Spots After Whole Genome Amplification
Deidentified newborn screening bloodspot samples (NBS) represent a valuable potential resource for genomic research if impediments to whole exome sequencing of NBS deoxyribonucleic acid (DNA), including the small amount of genomic DNA in NBS material, can be overcome. For instance, genomic analysis of NBS could be used to define allele frequencies of disease-associated variants in local populations, or to conduct prospective or retrospective studies relating genomic variation to disease emergence in pediatric populations over time. In this study, we compared the recovery of variant calls from exome sequences of amplified NBS genomic DNA to variant calls from exome sequencing of non-amplified NBS DNA from the same individuals. Results: Using a standard alignment-based Genome Analysis Toolkit (GATK), we find 62,000-76,000 additional variants in amplified samples. After application of a unique kmer enumeration and variant detection method (RUFUS), only 38,000-47,000 additional variants are observed in amplified gDNA. This result suggests that roughly half of the amplification-introduced variants identified using GATK may be the result of mapping errors and read misalignment. Conclusions: Our results show that it is possible to obtain informative, high-quality data from exome analysis of whole genome amplified NBS with the important caveat that different data generation and analysis methods can affect variant detection accuracy, and the concordance of variant calls in whole-genome amplified and non-amplified exomes.National Institute of Health P01HD067244, NS076465, R01ES021006Nutritional Science
Exocytosis from Large Dense Cored Vesicles as a Mechanism for Neuropeptide Release in the Peripheral and Central Nervous System
Nerve terminals often contain morphological-distinct populations of large (75-110 nm) and small (45-55 nm) vesicles. The small vesicles are speculated to account for release of transmitter quanta as they accumulate at presynaptic membranes. Large vesicles can co-store neuropeptides and classical transmitters but their function in neurotransmission has been disputed because they do not appear to accumulate at chemical synapses. However, there is now evidence that the large vesicles play a role in neuro-transmission or its modulation even though they may not be eminently involved in synaptic release. Thus, exocytosis occurs along the synapse-lacking membranes of peripheral noradrenergic varicosities. Large vesicles may continue to function in peptide release even after the classical transmitter has been depleted as demonstrated in the pig vas deferens. Three days of reserpine administration causes a parallel loss of noradrenaline and small vesicle contents but does not decrease enkephalin-like immunoreactivity or large vesicle electron density. In the central nervous system of the rat, where substance P and enkephalin have been localized to large vesicles, exocytosis occurs from several types of terminals. The large vesicles appear preferentially to release their contents at morphologically non-specialized sites even when characteristic synapses are present. Thus different mechanisms of transmitter and neuropeptide release may coexist. The nonsynaptic discharge may allow substances to diffuse over a wider distance whereas release into a synaptic cleft could restrict receptor interaction
Evolution of electronic states in n-type copper oxide superconductor via electric double layer gating
Since the discovery of n-type copper oxide superconductors, the evolution of
electron- and hole-bands and its relation to the superconductivity have been
seen as a key factor in unveiling the mechanism of high-Tc superconductors. So
far, the occurrence of electrons and holes in n-type copper oxides has been
achieved by chemical doping, pressure, and/or deoxygenation. However, the
observed electronic properties are blurred by the concomitant effects such as
change of lattice structure, disorder, etc. Here, we report on successful
tuning the electronic band structure of n-type Pr2-xCexCuO4 (x = 0.15)
ultrathin films, via the electric double layer transistor technique. Abnormal
transport properties, such as multiple sign reversals of Hall resistivity in
normal and mixed states, have been revealed within an electrostatic field in
range of -2 V to +2 V, as well as varying the temperature and magnetic field.
In the mixed state, the intrinsic anomalous Hall conductivity invokes the
contribution of both electron and hole-bands as well as the energy dependent
density of states near the Fermi level. The two-band model can also describe
the normal state transport properties well, whereas the carrier concentrations
of electrons and holes are always enhanced or depressed simultaneously in
electric fields. This is in contrast to the scenario of Fermi surface
reconstruction by antiferromagnetism, where an anti-correlation between
electrons and holes is commonly expected. Our findings paint the picture where
Coulomb repulsion plays an important role in the evolution of the electronic
states in n-type cuprate superconductors.Comment: 4 figures, SI not included. Comments are welcom
Low vitamin D status is associated with impaired bone quality and increased risk of fracture-related hospitalization in older Australian women
The vitamin D debate relates in part to ideal public health population levels of circulating 25-hydroxyvitamin D (25OHD) to maintain bone structure and reduce fracture. In a secondary analysis of 1,348 women aged 70-85 years at baseline (1998) from the Perth Longitudinal Study of Aging in Women (PLSAW, a five-year calcium supplementation trial followed by two five-year extensions), we examined the dose-response relations of baseline plasma 25OHD with hip DXA BMD at year 1, lumbar spine BMD and trabecular bone score (TBS) at year 5, and fracture-related hospitalizations over 14.5 years obtained by health record linkage. Mean baseline plasma 25OHD was 66.9±28.2 nmol/L and 28.5%, 36.4% and 35.1% of women had levels50 nmol/L are a minimum public health target and 25OHD levels beyond 75 nmol/L may not have additional benefit to reduce fracture risk
PRIMUS: The Effect of Physical Scale on the Luminosity-Dependence of Galaxy Clustering via Cross-Correlations
We report small-scale clustering measurements from the PRIMUS spectroscopic
redshift survey as a function of color and luminosity. We measure the
real-space cross-correlations between 62,106 primary galaxies with PRIMUS
redshifts and a tracer population of 545,000 photometric galaxies over
redshifts from z=0.2 to z=1. We separately fit a power-law model in redshift
and luminosity to each of three independent color-selected samples of galaxies.
We report clustering amplitudes at fiducial values of z=0.5 and L=1.5 L*. The
clustering of the red galaxies is ~3 times as strong as that of the blue
galaxies and ~1.5 as strong as that of the green galaxies. We also find that
the luminosity dependence of the clustering is strongly dependent on physical
scale, with greater luminosity dependence being found between r=0.0625 Mpc/h
and r=0.25 Mpc/h, compared to the r=0.5 Mpc/h to r=2 Mpc/h range. Moreover,
over a range of two orders of magnitude in luminosity, a single power-law fit
to the luminosity dependence is not sufficient to explain the increase in
clustering at both the bright and faint ends at the smaller scales. We argue
that luminosity-dependent clustering at small scales is a necessary component
of galaxy-halo occupation models for blue, star-forming galaxies as well as for
red, quenched galaxies.Comment: 13 pages, 6 figures, 5 tables; published in ApJ (revised to match
published version
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Valuation of pollination services from habitat management: a case study of utility scale solar energy facilities in the United States
Creating and maintaining pollinator habitats following the ecological infrastructure concept in degraded or unutilized land, such as solar energy facilities, is a practical way to synergistically advance the food, energy, and ecology nexus. Given the large land-use requirements for solar farming—the fastest growing renewable energy technology–considerable attention has been focused on strategies to maximize multiple ecosystem services. In this study, we coupled the principles of agronomy and ecology with economics and integrated national-scale data on crops, pollinators, and solar facilities to identify locations for creating pollinator habitats and estimating the economic value of pollination from the habitats. We examined opportunities for pollination services from pollinator-friendly utility-scale solar facilities adjacent to 42 million hectares of pollination-dependent crops in the conterminous United States at high resolution of 1 ha. We used the net income method to estimate the potential economic value of creating habitat in the land adjacent to solar facilities in the eight states with the greatest number of solar installations. Creating pollinator habitats at the 217 utility-scale solar facilities in these states could support adjacent 80,000 hectares of high pollinator dependent crops, which could potentially generate a pollination value of 120 USD to 264 million USD. The location-specific information and high-resolution maps generated for the United States demonstrate integration of grey and green infrastructure to support the food, energy, and environment nexus
PRIMUS: An observationally motivated model to connect the evolution of the AGN and galaxy populations out to z~1
We present an observationally motivated model to connect the AGN and galaxy
populations at 0.2<z<1.0 and predict the AGN X-ray luminosity function (XLF).
We start with measurements of the stellar mass function of galaxies (from the
Prism Multi-object Survey) and populate galaxies with AGNs using models for the
probability of a galaxy hosting an AGN as a function of specific accretion
rate. Our model is based on measurements indicating that the specific accretion
rate distribution is a universal function across a wide range of host stellar
mass with slope gamma_1 = -0.65 and an overall normalization that evolves with
redshift. We test several simple assumptions to extend this model to high
specific accretion rates (beyond the measurements) and compare the predictions
for the XLF with the observed data. We find good agreement with a model that
allows for a break in the specific accretion rate distribution at a point
corresponding to the Eddington limit, a steep power-law tail to super-Eddington
ratios with slope gamma_2 = -2.1 +0.3 -0.5, and a scatter of 0.38 dex in the
scaling between black hole and host stellar mass. Our results show that samples
of low luminosity AGNs are dominated by moderately massive galaxies (M* ~
10^{10-11} M_sun) growing with a wide range of accretion rates due to the shape
of the galaxy stellar mass function rather than a preference for AGN activity
at a particular stellar mass. Luminous AGNs may be a severely skewed population
with elevated black hole masses relative to their host galaxies and in rare
phases of rapid accretion.Comment: 11 pages, 5 figures, emulateapj format, updated to match version
accepted for publication in Ap
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