3,603 research outputs found
Recommended from our members
Previously Identified Genetic Variants in ADGRL3 Are not Associated with Risk for Equine Degenerative Myeloencephalopathy across Breeds.
Equine neuroaxonal dystrophy/equine degenerative myeloencephalopathy (eNAD/EDM) is a neurologic disease that has been reported in young horses from a wide range of breeds. The disease is inherited and associated with vitamin E deficiency during the first two years of life, resulting in bilateral symmetric ataxia. A missense mutation (chr3:71,917,591 C > T) within adhesion G protein-coupled receptor L3 (ADGRL3) was recently associated with risk for EDM in the Caspian breed. In order to confirm these findings, genotyping of this missense mutation, along with the three other associated single nucleotide polymorphisms (SNPs) in the genomic region, was carried out on 31 postmortem-confirmed eNAD/EDM cases and 43 clinically phenotyped controls from various breeds. No significant association was found between eNAD/EDM confirmed cases and genotype at any of the four identified SNPs (P > 0.05), including the nonsynonymous variant (EquCab2.0 chr3:71,917,591; allelic P = 0.85). These findings suggest that the four SNPs, including the missense variant in the ADGRL3 region, are not associated with risk for eNAD/EDM across multiple breeds of horses
Functional Forms for the Squeeze and the Time-Displacement Operators
Using Baker-Campbell-Hausdorff relations, the squeeze and harmonic-oscillator
time-displacement operators are given in the form , where ,
, , and are explicitly determined. Applications are
discussed.Comment: 10 pages, LaTe
Development and Uses of Upper-division Conceptual Assessment
The use of validated conceptual assessments alongside more standard course
exams has become standard practice for the introductory courses in many physics
departments. These assessments provide a more standard measure of certain
learning goals, allowing for comparisons of student learning across
instructors, semesters, and institutions. Researchers at the University of
Colorado Boulder have developed several similar assessments designed to target
the more advanced physics content of upper-division classical mechanics,
electrostatics, quantum mechanics, and electrodynamics. Here, we synthesize the
existing research on our upper-division assessments and discuss some of the
barriers and challenges associated with developing, validating, and
implementing these assessments as well as some of the strategies we have used
to overcome these barriers.Comment: 12 pages, 5 figures, submitted to the Phys. Rev. ST - PER Focused
collection on Upper-division PE
Gluelump Spectrum in the Bag Model
We explore the ordering of the lowest levels in a simple bag model of the
``gluelump'' of Michael and also discuss, again within the context of the bag
model, the related problem of hybrid potentials in the limit of very small
spacing between quark and anti-quark sources.Comment: 10 page
Notes
Notes by John M. Anderton, B. M. Apker, J. V. Wilcox, Leonard Boykin, Jr., John J. Broderick, Jr., Thomas F. Broden, Robert F. Burns, John E. Cosgrove, James K. Sugnet, and James D. Sullivan
Prototype 9.7 m Schwarzschild-Couder telescope for the Cherenkov Telescope Array: status of the optical system
The Cherenkov Telescope Array (CTA) is an international project for a
next-generation ground-based gamma ray observatory, aiming to improve on the
sensitivity of current-generation experiments by an order of magnitude and
provide energy coverage from 30 GeV to more than 300 TeV. The 9.7m
Schwarzschild-Couder (SC) candidate medium-size telescope for CTA exploits a
novel aplanatic two-mirror optical design that provides a large field of view
of 8 degrees and substantially improves the off-axis performance giving better
angular resolution across all of the field of view with respect to
single-mirror telescopes. The realization of the SC optical design implies the
challenging production of large aspherical mirrors accompanied by a
submillimeter-precision custom alignment system. In this contribution we report
on the status of the implementation of the optical system on a prototype 9.7 m
SC telescope located at the Fred Lawrence Whipple Observatory in southern
Arizona.Comment: Proceedings of the 35th International Cosmic Ray Conference (ICRC
2017), Busan, Korea. All CTA contributions at arXiv:1709.0348
Uncovering the Internal Structure of the Indian Financial Market: Cross-correlation behavior in the NSE
The cross-correlations between price fluctuations of 201 frequently traded
stocks in the National Stock Exchange (NSE) of India are analyzed in this
paper. We use daily closing prices for the period 1996-2006, which coincides
with the period of rapid transformation of the market following liberalization.
The eigenvalue distribution of the cross-correlation matrix, , of
NSE is found to be similar to that of developed markets, such as the New York
Stock Exchange (NYSE): the majority of eigenvalues fall within the bounds
expected for a random matrix constructed from mutually uncorrelated time
series. Of the few largest eigenvalues that deviate from the bulk, the largest
is identified with market-wide movements. The intermediate eigenvalues that
occur between the largest and the bulk have been associated in NYSE with
specific business sectors with strong intra-group interactions. However, in the
Indian market, these deviating eigenvalues are comparatively very few and lie
much closer to the bulk. We propose that this is because of the relative lack
of distinct sector identity in the market, with the movement of stocks
dominantly influenced by the overall market trend. This is shown by explicit
construction of the interaction network in the market, first by generating the
minimum spanning tree from the unfiltered correlation matrix, and later, using
an improved method of generating the graph after filtering out the market mode
and random effects from the data. Both methods show, compared to developed
markets, the relative absence of clusters of co-moving stocks that belong to
the same business sector. This is consistent with the general belief that
emerging markets tend to be more correlated than developed markets.Comment: 15 pages, 8 figures, to appear in Proceedings of International
Workshop on "Econophysics & Sociophysics of Markets & Networks"
(Econophys-Kolkata III), Mar 12-15, 200
Investigating strength and range of motion of the hip complex in ice hockey athletes
CONTEXT: Ice hockey athletes frequently injure the hip complex via a non-contact mechanism. We investigated patterns of strength and range of motion (ROM) to establish major differences compared to soccer athletes. Soccer athletes were compared to ice hockey athletes due to similarities between the two sports with regards to the intermittent nature and high number of lower limb injuries. OBJECTIVE: To compare the differences in ROM and strength of the hip for both the dominant (Dom) and non-dominant (Ndom) limb in ice hockey and soccer athletes. DESIGN: Case control study. SETTING: Bilateral ROM in hip flexion in sitting (FS) and lying (FL), extension, abduction, adduction, and internal rotation (IR) and external rotation (ER) was measured using a goniometer and assessed for strength using a hand held dynamometer on both the Dom and Ndom limbs. Participants. Twenty four male, active, uninjured NCAA division III ice hockey (16) and soccer (8) athletes. MAIN OUTCOME MEASURE: ROM and strength for hip FS, FL extension, abduction, adduction, IR and ER. A mixed model ANOVA was used to investigate interactions and main effects. RESULTS: Ice hockey athletes exhibited greater hip adduction ROM compared to soccer athletes in the Dom leg (both p=0.002) and when both limbs were combined (p = 0.010). Ice hockey athletes had less ROM in ER (p = 0.042) than soccer athletes. Ice hockey athletes displayed less strength in adduction in their Ndom leg compared to their Dom leg (p=0.02) along with less adduction than soccer players in their Ndom leg (p=0.40). Ice hockey athletes displayed less strength in hip adduction (p=0.030), FS (p=0.023) and FL (p=0.030) than soccer athletes. CONCLUSIONS: Our findings suggest that ice hockey athletes may present an 'at risk' profile for non-contact hip injuries, in comparison with soccer athletes with regards to strength and ROM of the hip
The nucleon's strange electromagnetic and scalar matrix elements
Quenched lattice QCD simulations and quenched chiral perturbation theory are
used together for this study of strangeness in the nucleon. Dependences of the
matrix elements on strange quark mass, valence quark mass and momentum transfer
are discussed in both the lattice and chiral frameworks. The combined results
of this study are in good agreement with existing experimental data and
predictions are made for upcoming experiments. Possible future refinements of
the theoretical method are suggested.Comment: 24 pages, 9 figure
Impact of interventions to reduce nosocomial transmission of SARS-CoV-2 in English NHS Trusts: a computational modelling study
Background: Prior to September 2021, 55,000–90,000 hospital inpatients in England were identified as having a potentially nosocomial SARS-CoV-2 infection. This includes cases that were likely missed due to pauci- or asymptomatic infection. Further, high numbers of healthcare workers (HCWs) are thought to have been infected, and there is evidence that some of these cases may also have been nosocomially linked, with both HCW to HCW and patient to HCW transmission being reported. From the start of the SARS-CoV-2 pandemic interventions in hospitals such as testing patients on admission and universal mask wearing were introduced to stop spread within and between patient and HCW populations, the effectiveness of which are largely unknown. Materials/methods: Using an individual-based model of within-hospital transmission, we estimated the contribution of individual interventions (together and in combination) to the effectiveness of the overall package of interventions implemented in English hospitals during the COVID-19 pandemic. A panel of experts in infection prevention and control informed intervention choice and helped ensure the model reflected implementation in practice. Model parameters and associated uncertainty were derived using national and local data, literature review and formal elicitation of expert opinion. We simulated scenarios to explore how many nosocomial infections might have been seen in patients and HCWs if interventions had not been implemented. We simulated the time period from March-2020 to July-2022 encompassing different strains and multiple doses of vaccination. Results: Modelling results suggest that in a scenario without inpatient testing, infection prevention and control measures, and reductions in occupancy and visitors, the number of patients developing a nosocomial SARS-CoV-2 infection could have been twice as high over the course of the pandemic, and over 600,000 HCWs could have been infected in the first wave alone. Isolation of symptomatic HCWs and universal masking by HCWs were the most effective interventions for preventing infections in both patient and HCW populations. Model findings suggest that collectively the interventions introduced over the SARS-CoV-2 pandemic in England averted 400,000 (240,000 – 500,000) infections in inpatients and 410,000 (370,000 – 450,000) HCW infections. Conclusions: Interventions to reduce the spread of nosocomial infections have varying impact, but the package of interventions implemented in England significantly reduced nosocomial transmission to both patients and HCWs over the SARS-CoV-2 pandemic
- …