573 research outputs found
Amorphous Phase Properties Of Oriented Polyethylene Solids
Solid-state deformation of polyethylene results in a preferential orientation of both crystalline and amorphous regions. Usually, one major problem in the prediction of the mechanical and thermal expansion properties of anisotropic polyethylene lies in determining values for the amorphous phase properties and, particularly, at a given level of solid-state deformation.
This paper outlines simple procedures for determining the two-dimensional amorphous orientation function and values for the mechanical and thermal expansion properties of the oriented amorphous phase. Mathematical expressions for determining the tensile and shear moduli, Poisson ratio and thermal strain of the amorphous phase for anisotropic polyethylene at any level of orientation are defined. Comparison between the predicted amorphous phase tensile modulus and the experimental measurements yields an agreement within 30%
Instrumentation for a Mars Entry Experiment
This paper is based on a preliminary design of an entry science package for a Voyager Mars entry and landing capsule. The introduction outlines the various conditions under which the instruments must operate and the range of anticipated measurement parameters. The following sections describe the technology survey, alternative measurement concepts considered, and the instruments selected for the entry science package. The last section is devoted to the complete subsystem operation, sequence of events, data handling, and the system of backup measurements
Intrinsic Genomic Differences Between African American and White Patients With Clear Cell Renal Cell Carcinoma
There are well-documented racial disparities in outcomes for African American patients with clear cell renal cell carcinoma (ccRCC). Despite a dramatic improvement in overall survival in white patients since the advent of targeted therapy, survival for African Americans with advanced ccRCC has not changed. There is little known about potential racial differences in tumor biology of ccRCC
Egér L 1210 leukémia kezelése 1-D-arabinofuranczilcytozinnel - matematikai modell és számítógépes szimuláció
Sex-Biased Gene Flow Among Elk in the Greater Yellowstone Ecosystem
We quantified patterns of population genetic structure to help understand gene flow among elk populations across the Greater Yellowstone Ecosystem. We sequenced 596 base pairs of the mitochondrial control region of 380 elk from eight populations. Analysis revealed high mitochondrial DNA variation within populations, averaging 13.0 haplotypes with high mean gene diversity (0.85). The genetic differentiation among populations for mitochondrial DNA was relatively high (FST = 0.161; P = 0.001) compared to genetic differentiation for nuclear microsatellite data (FST = 0.002; P = 0.332), which suggested relatively low female gene flow among populations. The estimated ratio of male to female gene flow (mm/mf = 46) was among the highest we have seen reported for large mammals. Genetic distance (for mitochondrial DNA pairwise FST) was not significantly correlated with geographic (Euclidean) distance between populations (Mantel’s r = 0.274, P = 0.168). Large mitochondrial DNA genetic distances (e.g., FST . 0.2) between some of the geographically closest populations (,65 km) suggested behavioral factors and/or landscape features might shape female gene flow patterns. Given the strong sex-biased gene flow, future research and conservation efforts should consider the sexes separately when modeling corridors of gene flow or predicting spread of maternally transmitted diseases. The growing availability of genetic data to compare male vs. female gene flow provides many exciting opportunities to explore the magnitude, causes, and implications of sex-biased gene flow likely to occur in many species
Standard Model Higgs boson production in association with a top anti-top pair at NLO with parton showering
We present predictions for the production cross section of a Standard Model
Higgs boson in association with a top-antitop pair at next-to-leading order
accuracy using matrix elements obtained from the HELAC-Oneloop package. The NLO
prediction was interfaced to the PYTHIA and HERWIG shower Monte Carlo programs
with the help of POWHEG-Box, allowing for decays of massive particles,
showering and hadronization, thus leading to final results at the hadron level.Comment: 14 pages, 9 figure
W + charm production with massive c quarks in PowHel
The hadroproduction of a boson in association with a charm quark at the
Large Hadron Collider is at the centre of current investigations due to its
potential to probe the strangeness content of the proton. In this paper we
present an implementation of the production process in the PowHel event
generator matched to the PYTHIA8 parton shower approach, allowing to obtain
predictions for differential cross-sections with NLO QCD accuracy matched to
the accuracy of the Shower Monte Carlo event generator. Effects of non-diagonal
CKM matrix elements, finite charm quark mass and off-shell decays including
spin correlations are taken into account. We investigate the production of a
leptonically decaying boson in association with either a charmed meson
() or a charmed jet () and compare our
predictions with particle-level measurements by the ATLAS and CMS
collaborations at 7 and 13 TeV. Considering the level of agreement
between theory predictions and experimental data in the light of present
theoretical and experimental uncertainties, our results do not point to the
need of extensive modifications of the strange and antistrange distribution
functions in the NLO PDF fits that we used, although collider
production data have not been included yet in these fits.Comment: 47 pages, 14 figure
High‐throughput competitive fluorescence polarization assay reveals functional redundancy in the S100 protein family
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