2,276 research outputs found
Granting gay rights does not lead to public opinion backlash, even among evangelicals.
More than a year ago, the US Supreme Court ruled that same-sex couples across the country had the right to marry. Ahead of that ruling, many commentators were concerned that there might be an anti-gay backlash if the right to marry was upheld by the Court. In new research using online survey experiments, Benjamin G. Bishin, Thomas J. Hayes, Matthew B. Incantalupo, and Charles Anthony Smith found no evidence of any backlash against same-sex marriage, even among more conservative groups such as Evangelical Christians
Genome position specific priors for genomic prediction
<p>Abstract</p> <p>Background</p> <p>The accuracy of genomic prediction is highly dependent on the size of the reference population. For small populations, including information from other populations could improve this accuracy. The usual strategy is to pool data from different populations; however, this has not proven as successful as hoped for with distantly related breeds. BayesRS is a novel approach to share information across populations for genomic predictions. The approach allows information to be captured even where the phase of SNP alleles and casuative mutation alleles are reversed across populations, or the actual casuative mutation is different between the populations but affects the same gene. Proportions of a four-distribution mixture for SNP effects in segments of fixed size along the genome are derived from one population and set as location specific prior proportions of distributions of SNP effects for the target population. The model was tested using dairy cattle populations of different breeds: 540 Australian Jersey bulls, 2297 Australian Holstein bulls and 5214 Nordic Holstein bulls. The traits studied were protein-, fat- and milk yield. Genotypic data was Illumina 777K SNPs, real or imputed.</p> <p>Results</p> <p>Results showed an increase in accuracy of up to 3.5% for the Jersey population when using BayesRS with a prior derived from Australian Holstein compared to a model without location specific priors. The increase in accuracy was however lower than was achieved when reference populations were combined to estimate SNP effects, except in the case of fat yield. The small size of the Jersey validation set meant that these improvements in accuracy were not significant using a Hotelling-Williams t-test at the 5% level. An increase in accuracy of 1-2% for all traits was observed in the Australian Holstein population when using a prior derived from the Nordic Holstein population compared to using no prior information. These improvements were significant (P<0.05) using the Hotelling Williams t-test for protein- and fat yield.</p> <p>Conclusion</p> <p>For some traits the method might be advantageous compared to pooling of reference data for distantly related populations, but further investigation is needed to confirm the results. For closely related populations the method does not perform better than pooling reference data. However, it does give an increased accuracy compared to analysis based on only one reference population, without an increased computational burden. The approach described here provides a general setup for inclusion of location specific priors: the approach could be used to include biological information in genomic predictions.</p
Not All Children with Cystic Fibrosis Have Abnormal Esophageal Neutralization during Chemical Clearance of Acid Reflux.
PurposeAcid neutralization during chemical clearance is significantly prolonged in children with cystic fibrosis, compared to symptomatic children without cystic fibrosis. The absence of available reference values impeded identification of abnormal findings within individual patients with and without cystic fibrosis. The present study aimed to test the hypothesis that significantly more children with cystic fibrosis have acid neutralization durations during chemical clearance that fall outside the physiological range.MethodsPublished reference value for acid neutralization duration during chemical clearance (determined using combined impedance/pH monitoring) was used to assess esophageal acid neutralization efficiency during chemical clearance in 16 children with cystic fibrosis (3 to <18 years) and 16 age-matched children without cystic fibrosis.ResultsDuration of acid neutralization during chemical clearance exceeded the upper end of the physiological range in 9 of 16 (56.3%) children with and in 3 of 16 (18.8%) children without cystic fibrosis (p=0.0412). The likelihood ratio for duration indicated that children with cystic fibrosis are 2.1-times more likely to have abnormal acid neutralization during chemical clearance, and children with abnormal acid neutralization during chemical clearance are 1.5-times more likely to have cystic fibrosis.ConclusionSignificantly more (but not all) children with cystic fibrosis have abnormally prolonged esophageal clearance of acid. Children with cystic fibrosis are more likely to have abnormal acid neutralization during chemical clearance. Additional studies involving larger sample sizes are needed to address the importance of genotype, esophageal motility, composition and volume of saliva, and gastric acidity on acid neutralization efficiency in cystic fibrosis children
Genetic correlates of longevity and selected age-related phenotypes: a genome-wide association study in the Framingham Study
BACKGROUND: Family studies and heritability estimates provide evidence for a genetic contribution to variation in the human life span. METHODS:We conducted a genome wide association study (Affymetrix 100K SNP GeneChip) for longevity-related traits in a community-based sample. We report on 5 longevity and aging traits in up to 1345 Framingham Study participants from 330 families. Multivariable-adjusted residuals were computed using appropriate models (Cox proportional hazards, logistic, or linear regression) and the residuals from these models were used to test for association with qualifying SNPs (70, 987 autosomal SNPs with genotypic call rate [greater than or equal to]80%, minor allele frequency [greater than or equal to]10%, Hardy-Weinberg test p [greater than or equal to] 0.001).RESULTS:In family-based association test (FBAT) models, 8 SNPs in two regions approximately 500 kb apart on chromosome 1 (physical positions 73,091,610 and 73, 527,652) were associated with age at death (p-value < 10-5). The two sets of SNPs were in high linkage disequilibrium (minimum r2 = 0.58). The top 30 SNPs for generalized estimating equation (GEE) tests of association with age at death included rs10507486 (p = 0.0001) and rs4943794 (p = 0.0002), SNPs intronic to FOXO1A, a gene implicated in lifespan extension in animal models. FBAT models identified 7 SNPs and GEE models identified 9 SNPs associated with both age at death and morbidity-free survival at age 65 including rs2374983 near PON1.
In the analysis of selected candidate genes, SNP associations (FBAT or GEE p-value < 0.01) were identified for age at death in or near the following genes: FOXO1A, GAPDH, KL, LEPR, PON1, PSEN1, SOD2, and WRN. Top ranked SNP associations in the GEE model for age at natural menopause included rs6910534 (p = 0.00003) near FOXO3a and rs3751591 (p = 0.00006) in CYP19A1. Results of all longevity phenotype-genotype associations for all autosomal SNPs are web posted at http://www.ncbi.nlm.nih.gov/projects/gap/cgi-bin/study.cgi?id=phs000007. CONCLUSION: Longevity and aging traits are associated with SNPs on the Affymetrix 100K GeneChip. None of the associations achieved genome-wide significance. These data generate hypotheses and serve as a resource for replication as more genes and biologic pathways are proposed as contributing to longevity and healthy aging
Buoyancy Instabilities in Galaxy Clusters: Convection Due to Adiabatic Cosmic Rays and Anisotropic Thermal Conduction
Using a linear stability analysis and two and three-dimensional nonlinear
simulations, we study the physics of buoyancy instabilities in a combined
thermal and relativistic (cosmic ray) plasma, motivated by the application to
clusters of galaxies. We argue that cosmic ray diffusion is likely to be slow
compared to the buoyancy time on large length scales, so that cosmic rays are
effectively adiabatic. If the cosmic ray pressure is of
the thermal pressure, and the cosmic ray entropy (;
is the thermal plasma density) decreases outwards, cosmic rays drive an
adiabatic convective instability analogous to Schwarzschild convection in
stars. Global simulations of galaxy cluster cores show that this instability
saturates by reducing the cosmic ray entropy gradient and driving efficient
convection and turbulent mixing. At larger radii in cluster cores, the thermal
plasma is unstable to the heat flux-driven buoyancy instability (HBI), a
convective instability generated by anisotropic thermal conduction and a
background conductive heat flux. Cosmic-ray driven convection and the HBI may
contribute to redistributing metals produced by Type 1a supernovae in clusters.
Our calculations demonstrate that adiabatic simulations of galaxy clusters can
artificially suppress the mixing of thermal and relativistic plasma;
anisotropic thermal conduction allows more efficient mixing, which may
contribute to cosmic rays being distributed throughout the cluster volume.Comment: submitted to ApJ; 15 pages and 12 figures; abstract shortened to < 24
lines; for high resolution movies see
http://astro.berkeley.edu/~psharma/clustermovie.htm
In situ characterization of cofacial Co(IV) centers in Co_4O_4 cubane: Modeling the high-valent active site in oxygen-evolving catalysts
The Co_4O_4 cubane is a representative structural model of oxidic cobalt oxygen-evolving catalysts (Co-OECs). The Co-OECs are active when residing at two oxidation levels above an all-Co(III) resting state. This doubly oxidized Co(IV)_2 state may be captured in a Co(III)_2(IV)_2 cubane. We demonstrate that the Co(III)_2(IV)_2 cubane may be electrochemically generated and the electronic properties of this unique high-valent state may be probed by in situ spectroscopy. Intervalence charge-transfer (IVCT) bands in the near-IR are observed for the Co(III)_2(IV)_2 cubane, and spectroscopic analysis together with electrochemical kinetics measurements reveal a larger reorganization energy and a smaller electron transfer rate constant for the doubly versus singly oxidized cubane. Spectroelectrochemical X-ray absorption data further reveal systematic spectral changes with successive oxidations from the cubane resting state. Electronic structure calculations correlated to experimental data suggest that this state is best represented as a localized, antiferromagnetically coupled Co(IV)_2 dimer. The exchange coupling in the cofacial Co(IV)_2 site allows for parallels to be drawn between the electronic structure of the Co_4O_4 cubane model system and the high-valent active site of the Co-OEC, with specific emphasis on the manifestation of a doubly oxidized Co(IV)_2 center on O-O bond formation
Effects of Surface Geology on Seismic Ground Motion Deduced from Ambient-Noise Measurements in the Town of Avellino, Irpinia Region (Italy)
The effects of surface geology on ground motion
provide an important tool in seismic hazard studies. It is well
known that the presence of soft sediments can cause amplification
of the ground motion at the surface, particularly when there is a
sharp impedance contrast at shallow depth. The town of Avellino is
located in an area characterised by high seismicity in Italy, about
30 km from the epicentre of the 23 November 1980, Irpinia
earthquake (M = 6.9). No earthquake recordings are available in
the area. The local geology is characterised by strong heterogeneity,
with impedance contrasts at depth. We present the results
from seismic noise measurements carried out in the urban area of
Avellino to evaluate the effects of local geology on the seismic
ground motion. We computed the horizontal-to-vertical (H/V)
noise spectral ratios at 16 selected sites in this urban area for which
drilling data are available within the first 40 m of depth. A Rayleigh
wave inversion technique using the peak frequencies of the
noise H/V spectral ratios is then presented for estimating Vs
models, assuming that the thicknesses of the shallow soil layers are
known. The results show a good correspondence between experimental
and theoretical peak frequencies, which are interpreted in
terms of sediment resonance. For one site, which is characterised
by a broad peak in the horizontal-to-vertical spectral-ratio curve,
simple one-dimensional modelling is not representative of the
resonance effects. Consistent variations in peak amplitudes are seen
among the sites. A site classification based on shear-wave velocity
characteristics, in terms of Vs30, cannot explain these data. The
differences observed are better correlated to the impedance contrast
between the sediments and basement. A more detailed investigation
of the physical parameters of the subsoil structure, together with
earthquake data, are desirable for future research, to confirm these
data in terms of site response
Characterization and modeling of the Haemophilus influenzae core and supragenomes based on the complete genomic sequences of Rd and 12 clinical nontypeable strains
The genomes of 9 non-typeable H. influenzae clinical isolates were sequenced and compared with a reference strain, allowing the characterisation and modelling of the core-and supra genomes of this organism
A novel method for radiotherapy patient identification using surface imaging
Performing a procedure on the wrong patient or site is one of the greatest errors that can occur in medicine. The addition of automation has been shown to reduce errors in many processes. In this work we explore the use of an automated patient identification process using optical surface imaging for radiotherapy treatments. Surface imaging uses visible light to align the patient to a reference surface in the treatment room. It is possible to evaluate the similarity between a daily set-up surface image and the reference image using distance to agreement between the points on the two surfaces. The higher the percentage overlapping points within a defined distance, the more similar the surfaces. This similarity metric was used to intercompare 16 left-sided breast patients. The reference surface for each patient was compared to 10 daily treatment surfaces for the same patient, and 10 surfaces from each of the other 15 patients (for a total of 160 comparisons per patient), looking at the percent of points overlapping. For each patient, the minimum same-patient similarity score was higher than the maximum different-patient score. For the group as a whole a threshold was able to classify correct and incorrect patients with high levels of accuracy. A 10-fold cross-validation using linear discriminant analysis gave cross-validation loss of 0.0074. An automated process using surface imaging is a feasible option to provide nonharmful daily patient identification verification using currently available technology
Integration of highly probabilistic sources into optical quantum architectures: perpetual quantum computation
In this paper we introduce a design for an optical topological cluster state
computer constructed exclusively from a single quantum component. Unlike
previous efforts we eliminate the need for on demand, high fidelity photon
sources and detectors and replace them with the same device utilised to create
photon/photon entanglement. This introduces highly probabilistic elements into
the optical architecture while maintaining complete specificity of the
structure and operation for a large scale computer. Photons in this system are
continually recycled back into the preparation network, allowing for a
arbitrarily deep 3D cluster to be prepared using a comparatively small number
of photonic qubits and consequently the elimination of high frequency,
deterministic photon sources.Comment: 19 pages, 13 Figs (2 Appendices with additional Figs.). Comments
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