3,423 research outputs found
Epidemiology of National Collegiate Athletic Association men's and women's swimming and diving injuries from 2009/2010 to 2013/2014
BACKGROUND: Recent injury data for collegiate-level swimming and diving are limited. This study describes the epidemiology of men's and women's swimming and diving injuries reported by the National Collegiate Athletic Association (NCAA) Injury Surveillance Program (ISP) during the 2009/2010 to 2013/2014 academic years.
METHODS: Injuries and athlete-exposure (AE) data reported within 9 men's and 13 women's swimming and diving programmes were analysed. Injury rates, injury rate ratios (IRR), and injury proportions by body site, diagnosis and mechanism were reported with 95% CIs.
RESULTS: The ISP captured 149 and 208 injuries for men's and women's swimming and diving, respectively, leading to injury rates of 1.54/1000 and 1.71/1000 AEs. Among females, divers had a higher injury rate (2.49/1000 AEs) than swimmers (1.63/1000 AEs; IRR=1.53; 95% CI 1.07 to 2.19). Injury rates for male divers (1.94/1000 AEs) and swimmers (1.48/1000 AEs) did not differ (IRR=1.33; 95% CI 0.85 to 2.31). Most injuries occurred to the shoulder, resulted in strains and were classified as overuse or non-contact. Female swimmers had a higher overuse injury rate (1.04/1000 AEs) than male swimmers (0.66/1000 AEs; IRR=1.58; 95% CI 1.14 to 2.19). Overuse injury rates for female divers (0.54/1000 AEs) and male divers (0.46/1000 AEs) did not differ (IRR=1.16; 95% CI 0.40 to 3.34). Injury rates in 2012/2013-2013/2014 were lower than those in 2009/2010-2011/2012 for women's swimming (IRR=0.70; 95% CI 0.52 to 0.95) and diving (IRR=0.56; 95% CI 0.30 to 1.08), respectively. No time trends existed for men's swimmers or divers.
CONCLUSIONS: Shoulder, strain and overuse injuries were common in collegiate men's and women's swimming and diving. Female swimmers were more likely to suffer an overuse injury than male swimmers. In addition, divers may have higher injury rates than swimmers, although small reported numbers warrant additional research
Systematic interaction network filtering identifies CRMP1 as a novel suppressor of huntingtin misfolding and neurotoxicity
Assemblies of huntingtin (HTT) fragments with expanded polyglutamine (polyQ) tracts are a pathological hallmark of Huntington's disease (HD). The molecular mechanisms by which these structures are formed and cause neuronal dysfunction and toxicity are poorly understood. Here, we utilized available gene expression data sets of selected brain regions of HD patients and controls for systematic interaction network filtering in order to predict disease-relevant, brain region-specific HTT interaction partners. Starting from a large protein-protein interaction (PPI) data set, a step-by-step computational filtering strategy facilitated the generation of a focused PPI network that directly or indirectly connects 13 proteins potentially dysregulated in HD with the disease protein HTT. This network enabled the discovery of the neuron-specific protein CRMP1 that targets aggregation-prone, N-terminal HTT fragments and suppresses their spontaneous self-assembly into proteotoxic structures in various models of HD. Experimental validation indicates that our network filtering procedure provides a simple but powerful strategy to identify disease-relevant proteins that influence misfolding and aggregation of polyQ disease proteins.DFG [SFB740, 740/2-11, SFB618, 618/3-09, SFB/TRR43 A7]; BMBF(NGFN-Plus) [01GS08169-73, 01GS08150, 01GS08108]; HDSA Coalition for the Cure; EU (EuroSpin) [Health-F2-2009-241498, HEALTH-F2-2009-242167]; Helmholtz Association (MSBN, HelMA) [HA-215]; FCT [IF/00881/2013]info:eu-repo/semantics/publishedVersio
Injury Rates in Age-Only Versus Age-and-Weight Playing Standard Conditions in American Youth Football
BACKGROUND: American youth football leagues are typically structured using either age-only (AO) or age-and-weight (AW) playing standard conditions. These playing standard conditions group players by age in the former condition and by a combination of age and weight in the latter condition. However, no study has systematically compared injury risk between these 2 playing standards.
PURPOSE: To compare injury rates between youth tackle football players in the AO and AW playing standard conditions.
STUDY DESIGN: Cohort study; Level of evidence, 2.
METHODS: Athletic trainers evaluated and recorded injuries at each practice and game during the 2012 and 2013 football seasons. Players (age, 5-14 years) were drawn from 13 recreational leagues across 6 states. The sample included 4092 athlete-seasons (AW, 2065; AO, 2027) from 210 teams (AW, 106; O, 104). Injury rate ratios (RRs) with 95% CIs were used to compare the playing standard conditions. Multivariate Poisson regression was used to estimate RRs adjusted for residual effects of age and clustering by team and league. There were 4 endpoints of interest: (1) any injury, (2) non-time loss (NTL) injuries only, (3) time loss (TL) injuries only, and (4) concussions only.
RESULTS: Over 2 seasons, the cohort accumulated 1475 injuries and 142,536 athlete-exposures (AEs). The most common injuries were contusions (34.4%), ligament sprains (16.3%), concussions (9.6%), and muscle strains (7.8%). The overall injury rate for both playing standard conditions combined was 10.3 per 1000 AEs (95% CI, 9.8-10.9). The TL injury, NTL injury, and concussion rates in both playing standard conditions combined were 3.1, 7.2, and 1.0 per 1000 AEs, respectively. In multivariate Poisson regression models controlling for age, team, and league, no differences were found between playing standard conditions in the overall injury rate (RRoverall, 1.1; 95% CI, 0.4-2.6). Rates for the other 3 endpoints were also similar (RRNTL, 1.1 [95% CI, 0.4-3.0]; RRTL, 0.9 [95% CI, 0.4-1.9]; RRconcussion, 0.6 [95% CI, 0.3-1.4]).
CONCLUSION: For the injury endpoints examined in this study, the injury rates were similar in the AO and AW playing standards. Future research should examine other policies, rules, and behavioral factors that may affect injury risk within youth football
Improving Cosmological Distance Measurements Using Twin Type Ia Supernovae
We introduce a method for identifying "twin" Type Ia supernovae, and using
them to improve distance measurements. This novel approach to Type Ia supernova
standardization is made possible by spectrophotometric time series observations
from the Nearby Supernova Factory (SNfactory). We begin with a well-measured
set of supernovae, find pairs whose spectra match well across the entire
optical window, and then test whether this leads to a smaller dispersion in
their absolute brightnesses. This analysis is completed in a blinded fashion,
ensuring that decisions made in implementing the method do not inadvertently
bias the result. We find that pairs of supernovae with more closely matched
spectra indeed have reduced brightness dispersion. We are able to standardize
this initial set of SNfactory supernovae to 0.083 +/- 0.012 magnitudes,
implying a dispersion of 0.072 +/- 0.010 magnitudes in the absence of peculiar
velocities. We estimate that with larger numbers of comparison SNe, e.g, using
the final SNfactory spectrophotometric dataset as a reference, this method will
be capable of standardizing high-redshift supernovae to within 0.06-0.07
magnitudes. These results imply that at least 3/4 of the variance in Hubble
residuals in current supernova cosmology analyses is due to previously
unaccounted-for astrophysical differences among the supernovaeComment: 37 pages, 9 figures, 5 tables. Accepted for publication in ApJ. Fixed
typo in arXiv abstrac
The Extinction Properties of and Distance to the Highly Reddened Type Ia Supernova SN 2012cu
Correction of Type Ia Supernova brightnesses for extinction by dust has
proven to be a vexing problem. Here we study the dust foreground to the highly
reddened SN 2012cu, which is projected onto a dust lane in the galaxy NGC 4772.
The analysis is based on multi-epoch, spectrophotometric observations spanning
3,300 - 9,200 {\AA}, obtained by the Nearby Supernova Factory. Phase-matched
comparison of the spectroscopically twinned SN 2012cu and SN 2011fe across 10
epochs results in the best-fit color excess of (E(B-V), RMS) = (1.00, 0.03) and
total-to-selective extinction ratio of (RV , RMS) = (2.95, 0.08) toward SN
2012cu within its host galaxy. We further identify several diffuse interstellar
bands, and compare the 5780 {\AA} band with the dust-to-band ratio for the
Milky Way. Overall, we find the foreground dust-extinction properties for SN
2012cu to be consistent with those of the Milky Way. Furthermore we find no
evidence for significant time variation in any of these extinction tracers. We
also compare the dust extinction curve models of Cardelli et al. (1989),
O'Donnell (1994), and Fitzpatrick (1999), and find the predictions of
Fitzpatrick (1999) fit SN 2012cu the best. Finally, the distance to NGC4772,
the host of SN 2012cu, at a redshift of z = 0.0035, often assigned to the Virgo
Southern Extension, is determined to be 16.61.1 Mpc. We compare this
result with distance measurements in the literature.Comment: 48 pages, 13 figures. Accepted for publication in The Astrophysical
Journal. The spectral time series data presented in this article can be found
at http://snfactory.lbl.gov/snf/data
Entanglement of two-mode Gaussian states: characterization and experimental production and manipulation
A powerful theoretical structure has emerged in recent years on the
characterization and quantification of entanglement in continuous-variable
systems. After reviewing this framework, we will illustrate it with an original
set-up based on a type-II OPO with adjustable mode coupling. Experimental
results allow a direct verification of many theoretical predictions and provide
a sharp insight into the general properties of two-mode Gaussian states and
entanglement resource manipulation
The Subluminous and Peculiar Type Ia Supernova PTF09dav
PTF09dav is a peculiar subluminous type Ia supernova (SN) discovered by the
Palomar Transient Factory (PTF). Spectroscopically, it appears superficially
similar to the class of subluminous SN1991bg-like SNe, but it has several
unusual features which make it stand out from this population. Its peak
luminosity is fainter than any previously discovered SN1991bg-like SN Ia (M_B
-15.5), but without the unusually red optical colors expected if the faint
luminosity were due to extinction. The photospheric optical spectra have very
unusual strong lines of Sc II and Mg I, with possible Sr II, together with
stronger than average Ti II and low velocities of ~6000 km/s. The host galaxy
of PTF09dav is ambiguous. The SN lies either on the extreme outskirts (~41kpc)
of a spiral galaxy, or in an very faint (M_R>-12.8) dwarf galaxy, unlike other
1991bg-like SNe which are invariably associated with massive, old stellar
populations. PTF09dav is also an outlier on the light-curve-width--luminosity
and color--luminosity relations derived for other sub-luminous SNe Ia. The
inferred 56Ni mass is small (0.019+/-0.003Msun), as is the estimated ejecta
mass of 0.36Msun. Taken together, these properties make PTF09dav a remarkable
event. We discuss various physical models that could explain PTF09dav. Helium
shell detonation or deflagration on the surface of a CO white-dwarf can explain
some of the features of PTF09dav, including the presence of Sc and the low
photospheric velocities, but the observed Si and Mg are not predicted to be
very abundant in these models. We conclude that no single model is currently
capable of explaining all of the observed signatures of PTF09dav.Comment: Accepted for publication in Ap
Type Ia Supernova Rate Measurements To Redshift 2.5 From CANDELS: Searching For Prompt Explosions In The Early Universe
dThe Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS) was a multi-cycle treasury program on the Hubble Space Telescope (HST) that surveyed a total area of -0.25 deg2 with -900 HST orbits spread across five fields over three years. Within these survey images we discovered 65 supernovae (SNe) of all types, out to z 2.5. We classify -24 of these as Type Ia SNe (SNe Ia) based on host galaxy redshifts and SN photometry (supplemented by grism spectroscopy of six SNe). Here we present a measurement of the volumetric SN Ia rate as a function of redshift, reaching for the first time beyond z =- 2 and putting new constraints on SN Ia progenitor models. Our highest redshift bin includes detections of SNe that exploded when the universe was only -3 Gyr old and near the peak of the cosmic star formation history. This gives the CANDELS high redshift sample unique leverage for evaluating the fraction of SNe Ia that explode promptly after formation ( 40 Myr. However, mild tension is apparent between ground-based low-z surveys and space-based high-z surveys. In both CANDELS and the sister HST program CLASH (Cluster Lensing And Supernova Survey with Hubble), we find a low rate of SNe Ia at z > 1. This could be a hint that prompt progenitors are in fact relatively rare, accounting for only 20% of all SN Ia explosions-though further analysis and larger samples will be needed to examine that suggestion. Key words: infrared: general - supernovae:Astronom
Incidence of Concussion During Practice and Games in Youth, High School, and Collegiate American Football Players
IMPORTANCE: A report by the Institute of Medicine called for comprehensive nationwide concussion incidence data across the spectrum of athletes aged 5 to 23 years.
OBJECTIVE: To describe the incidence of concussion in athletes participating in youth, high school, and collegiate American football.
DESIGN, SETTING, AND PARTICIPANTS: Data were collected by athletic trainers at youth, high school, and collegiate football practices and games to create multiple prospective observational cohorts during the 2012 and 2013 football seasons. Data were collected from July 1, 2012, through January 31, 2013, for the 2012 season and from July 1, 2013, through January 31, 2014, for the 2013 season. The Youth Football Surveillance System included 118 youth football teams, providing 4092 athlete-seasons. The National Athletic Treatment, Injury and Outcomes Network program included 96 secondary school football programs, providing 11 957 athlete-seasons. The National Collegiate Athletic Association Injury Surveillance Program included 24 member institutions, providing 4305 athlete-seasons.
EXPOSURES: All injuries regardless of severity, including concussions, and athlete exposure information were documented by athletic trainers during practices and games.
MAIN OUTCOMES AND MEASURES: Injury rates, injury rate ratios, risks, risk ratios, and 95% CIs were calculated.
RESULTS: Concussions comprised 9.6%, 4.0%, and 8.0% of all injuries reported in the Youth Football Surveillance System; National Athletic Treatment, Injury and Outcomes Network; and National Collegiate Athletic Association Injury Surveillance Program, respectively. The game concussion rate was higher than the practice concussion rate across all 3 competitive levels. The game concussion rate for college athletes (3.74 per 1000 athlete exposures) was higher than those for high school athletes (injury rate ratio, 1.86; 95% CI, 1.50-2.31) and youth athletes (injury rate ratio, 1.57; 95% CI, 1.17-2.10). The practice concussion rate in college (0.53 per 1000 athlete exposures) was lower than that in high school (injury rate ratio, 0.80; 95% CI, 0.67-0.96). Youth football had the lowest 1-season concussion risks in 2012 (3.53%) and 2013 (3.13%). The 1-season concussion risk was highest in high school (9.98%) and college (5.54%) in 2012.
CONCLUSIONS AND RELEVANCE: Football practices were a major source of concussion at all 3 levels of competition. Concussions during practice might be mitigated and should prompt an evaluation of technique and head impact exposure. Although it is more difficult to change the intensity or conditions of a game, many strategies can be used during practice to limit player-to-player contact and other potentially injurious behaviors
Screening, Brief Intervention, and Referral to Treatment for Pain Management for Veterans Seeking Service-Connection Payments for Musculoskeletal Disorders: SBIRT-PM Study Protocol
BACKGROUND: Veterans with significant chronic pain from musculoskeletal disorders are at risk of substance misuse. Veterans whose condition is the result of military service may be eligible for a disability pension. Department of Veterans Affairs compensation examinations, which determine the degree of disability and whether it was connected to military service, represent an opportunity to engage Veterans in pain management and substance use treatments. A multisite randomized clinical trial is testing the effectiveness and cost-effectiveness of Screening, Brief Intervention, and Referral to Treatment for Pain Management (SBIRT-PM) for Veterans seeking compensation for musculoskeletal disorders. This telephone-based intervention is delivered through a hub-and-spoke configuration.
DESIGN: This study is a two-arm, parallel-group, 36-week, multisite randomized controlled single-blind trial. It will randomize 1,100 Veterans experiencing pain and seeking service-connection for musculoskeletal disorders to either SBIRT-PM or usual care across eight New England VA medical centers. The study balances pragmatic with explanatory methodological features. Primary outcomes are pain severity and number of substances misused. Nonpharmacological pain management and substance use services utilization are tracked in the trial.
SUMMARY: Early trial enrollment targets were met across sites. SBIRT-PM could help Veterans, at the time of their compensation claims, use multimodal pain treatments and reduce existing substance misuse. Strategies to address COVID-19 pandemic impacts on the SBIRT-PM protocol have been developed to maintain its pragmatic and exploratory integrity
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