Do Female University Varsity Athletes Have a Greater Risk of Injury Within a Competitive Varsity Season?

International Journal of Exercise Science 16(6): 129-147, 2023. Previous varsity sport injury research has analyzed how acute and chronic injury severity, type, and location differs between sport and sexes, with limited research in time to injury. Canadian university varsity sport injury research is especially sparse and mostly retrospective. Thus, we aimed to understand injury differences in male and female competitive university athletes competing in the same sport. Athletes who competed on the basketball, volleyball, soccer, ice hockey, football (male), rugby (female), and wrestling teams were eligible for the study. There were 182 male and 113 female athletes who provided informed consent to be prospectively followed over a season. Injury date, type, location, chronicity, and events missed due to injury were recorded on a weekly basis. Overall, the percentage of male (68.7%) and female (68.1%) athletes injured was not different. No overall sex differences (variables collapsed) were observed in injury chronicity, location, type, events lost, mean number of injuries, or time to injury. Within sport differences existed for mean number of injuries, injury location, type of injury, and events missed. Mean time to injury in female basketball (28 days) and volleyball athletes (14 days) was significantly shorter compared to male basketball (67 days) and volleyball (65 days). Time to a concussion was significantly shorter in females overall compared to males. These results indicate that Canadian female university age athletes are not inherently more susceptible to injury, but female athletes within certain sports may have increased injury risk which could shorten time to injury (basketball, volleyball) and increase the number of events missed due to injury (hockey)

The Forgotten Quail Decline: The Plight of Scaled Quail in Texas

Several quail species are experiencing range-wide declines in the United States. The northern bobwhite (Colinus virginianus) has garnered the most attention, both from a research and conservation perspective. The bobwhite decline in Texas, has resulted in considerable time and effort being devoted to research and management on the species due to its status as a highly popular and economically important game bird. This attention has been beneficial to bobwhite conservation and management but, an unfortunate consequence of this focus has been neglect of the scaled quail (Callipepla squamata) that has been declining at even a more alarming rate. Scaled quail, according to Breeding Bird Survey (BBS) data, have declined at a rate of 5.1% per year in the Tamaulipan Biotic Province (southern Texas), the greatest of any region surveyed in its geographic range. Anecdotal reports of landowners have long noted the gradual disappearance of scaled quail and concomitant replacement with northern bobwhite throughout southern Texas, beginning since about the 1990s. Analysis of BBS data provides evidence for this replacement. Percent of quail detections in the core of the scaled quail range in the Tamaulipan Biotic Province were 80:20 (scaled quail: bobwhite) during the 1960s but currently represent about 5:95. In addition, the range of scaled quail has been contracting, moving progressively west with time. The species is no longer detected on the easternmost BBS routes in southern Texas

The Effect of Different Training Loads on the Lung Health of Competitive Youth Swimmers

International Journal of Exercise Science 11(6): 999-1018, 2018. Airway hyperresponsiveness (AHR), airway inflammation, and respiratory symptoms are common in competitive swimmers, however it is unclear how volume and intensity of training exacerbate these problems. Thus, our purpose was to measure AHR, inflammation, and respiratory symptoms after low, moderate, and high training loads in swimmers. Competitive youth swimmers (n=8) completed nine weeks of training split into three blocks (Low, Moderate, and High intensity). Spirometry at rest and post-bronchial provocation [Eucapnic Voluntary Hyperpnea (EVH)] and Fractional Exhaled Nitric Oxide (FeNO) were completed at the end of each training block. A weekly self-report questionnaire determined respiratory symptoms. Session Rating of Perceived Exertion (sRPE) quantified internal training loads. Internal load was significantly lower after Moderate training (4840 ± 971 AU) than after High training (5852 ± 737 AU) (p= 0.02, d= 1.17). Pre-EVH FEV1was significantly decreased after Moderate (4.52 ± 0.69 L) compared to Low (4.74 ± 0.63 L) (p= 0.025, d= 0.326), but not different from High load. Post-EVH FeNO after Moderate training was significantly decreased (9.4 ± 4.9 ppb) compared to Low training (15.4 ± 3.6 ppb) (p= 0.012, r= 0.884).Respiratory symptom frequency was significantly correlated with percent decrease in FEV120 minutes post-EVH after Low and Moderate loads (both ρ= -0.71, sig = 0.05), and after High load was significantly correlated with percent decrease in FEV1at 10 (ρ= -0.74, sig = 0.03), 15 (ρ= -0.91, sig = 0.00), and 20 minutes post (ρ= -0.75, sig = 0.03). In conclusion, Moderate load training resulted in the worst lung health results, suggesting there may be factors other than the total amount of stress within training blocks that influence lung health. Further research is needed to determine the effect of manipulating specific acute training load variables on the lung health of swimmers

The Effect of Different Training Loads on the Lung Health of Competitive Youth Swimmers

International Journal of Exercise Science 11(6): 999-1018, 2018. Airway hyperresponsiveness (AHR), airway inflammation, and respiratory symptoms are common in competitive swimmers, however it is unclear how volume and intensity of training exacerbate these problems. Thus, our purpose was to measure AHR, inflammation, and respiratory symptoms after low, moderate, and high training loads in swimmers. Competitive youth swimmers (n=8) completed nine weeks of training split into three blocks (Low, Moderate, and High intensity). Spirometry at rest and post-bronchial provocation [Eucapnic Voluntary Hyperpnea (EVH)] and Fractional Exhaled Nitric Oxide (FeNO) were completed at the end of each training block. A weekly self-report questionnaire determined respiratory symptoms. Session Rating of Perceived Exertion (sRPE) quantified internal training loads. Internal load was significantly lower after Moderate training (4840 ± 971 AU) than after High training (5852 ± 737 AU) (p= 0.02, d= 1.17). Pre-EVH FEV1was significantly decreased after Moderate (4.52 ± 0.69 L) compared to Low (4.74 ± 0.63 L) (p= 0.025, d= 0.326), but not different from High load. Post-EVH FeNO after Moderate training was significantly decreased (9.4 ± 4.9 ppb) compared to Low training (15.4 ± 3.6 ppb) (p= 0.012, r= 0.884).Respiratory symptom frequency was significantly correlated with percent decrease in FEV120 minutes post-EVH after Low and Moderate loads (both ρ= -0.71, sig = 0.05), and after High load was significantly correlated with percent decrease in FEV1at 10 (ρ= -0.74, sig = 0.03), 15 (ρ= -0.91, sig = 0.00), and 20 minutes post (ρ= -0.75, sig = 0.03). In conclusion, Moderate load training resulted in the worst lung health results, suggesting there may be factors other than the total amount of stress within training blocks that influence lung health. Further research is needed to determine the effect of manipulating specific acute training load variables on the lung health of swimmers

Structure and Function of Iron-Loaded Synthetic Melanin

We describe a synthetic method for increasing and controlling the iron loading of synthetic melanin nanoparticles and use the resulting materials to perform a systematic quantitative investigation on their structure 12property relationship. A comprehensive analysis by magnetometry, electron paramagnetic resonance, and nuclear magnetic relaxation dispersion reveals the complexities of their magnetic behavior and how these intraparticle magnetic interactions manifest in useful material properties such as their performance as MRI contrast agents. This analysis allows predictions of the optimal iron loading through a quantitative modeling of antiferromagnetic coupling that arises from proximal iron ions. This study provides a detailed understanding of this complex class of synthetic biomaterials and gives insight into interactions and structures prevalent in naturally occurring melanins

A population of gamma-ray emitting globular clusters seen with the Fermi Large Area Telescope

Globular clusters with their large populations of millisecond pulsars (MSPs) are believed to be potential emitters of high-energy gamma-ray emission. Our goal is to constrain the millisecond pulsar populations in globular clusters from analysis of gamma-ray observations. We use 546 days of continuous sky-survey observations obtained with the Large Area Telescope aboard the Fermi Gamma-ray Space Telescope to study the gamma-ray emission towards 13 globular clusters. Steady point-like high-energy gamma-ray emission has been significantly detected towards 8 globular clusters. Five of them (47 Tucanae, Omega Cen, NGC 6388, Terzan 5, and M 28) show hard spectral power indices $(0.7 < \Gamma <1.4)$ and clear evidence for an exponential cut-off in the range 1.0-2.6 GeV, which is the characteristic signature of magnetospheric emission from MSPs. Three of them (M 62, NGC 6440 and NGC 6652) also show hard spectral indices $(1.0 < \Gamma < 1.7)$, however the presence of an exponential cut-off can not be unambiguously established. Three of them (Omega Cen, NGC 6388, NGC 6652) have no known radio or X-ray MSPs yet still exhibit MSP spectral properties. From the observed gamma-ray luminosities, we estimate the total number of MSPs that is expected to be present in these globular clusters. We show that our estimates of the MSP population correlate with the stellar encounter rate and we estimate 2600-4700 MSPs in Galactic globular clusters, commensurate with previous estimates. The observation of high-energy gamma-ray emission from a globular cluster thus provides a reliable independent method to assess their millisecond pulsar populations that can be used to make constraints on the original neutron star X-ray binary population, essential for understanding the importance of binary systems in slowing the inevitable core collapse of globular clusters.Comment: Accepted for publication in A&A. Corresponding authors: J. Kn\"odlseder, N. Webb, B. Pancraz

Fermi Large Area Telescope Constraints on the Gamma-ray Opacity of the Universe

The Extragalactic Background Light (EBL) includes photons with wavelengths from ultraviolet to infrared, which are effective at attenuating gamma rays with energy above ~10 GeV during propagation from sources at cosmological distances. This results in a redshift- and energy-dependent attenuation of the gamma-ray flux of extragalactic sources such as blazars and Gamma-Ray Bursts (GRBs). The Large Area Telescope onboard Fermi detects a sample of gamma-ray blazars with redshift up to z~3, and GRBs with redshift up to z~4.3. Using photons above 10 GeV collected by Fermi over more than one year of observations for these sources, we investigate the effect of gamma-ray flux attenuation by the EBL. We place upper limits on the gamma-ray opacity of the Universe at various energies and redshifts, and compare this with predictions from well-known EBL models. We find that an EBL intensity in the optical-ultraviolet wavelengths as great as predicted by the "baseline" model of Stecker et al. (2006) can be ruled out with high confidence.Comment: 42 pages, 12 figures, accepted version (24 Aug.2010) for publication in ApJ; Contact authors: A. Bouvier, A. Chen, S. Raino, S. Razzaque, A. Reimer, L.C. Reye

A regional Bayesian POT model for flood frequency analysis

Flood frequency analysis is usually based on the fitting of an extreme value distribution to the local streamflow series. However, when the local data series is short, frequency analysis results become unreliable. Regional frequency analysis is a convenient way to reduce the estimation uncertainty. In this work, we propose a regional Bayesian model for short record length sites. This model is less restrictive than the index flood model while preserving the formalism of "homogeneous regions". The performance of the proposed model is assessed on a set of gauging stations in France. The accuracy of quantile estimates as a function of the degree of homogeneity of the pooling group is also analysed. The results indicate that the regional Bayesian model outperforms the index flood model and local estimators. Furthermore, it seems that working with relatively large and homogeneous regions may lead to more accurate results than working with smaller and highly homogeneous regions

Gamma-ray and radio properties of six pulsars detected by the fermi large area telescope

We report the detection of pulsed γ-rays for PSRs J0631+1036, J0659+1414, J0742-2822, J1420-6048, J1509-5850, and J1718-3825 using the Large Area Telescope on board the Fermi Gamma-ray Space Telescope (formerly known as GLAST). Although these six pulsars are diverse in terms of their spin parameters, they share an important feature: their γ-ray light curves are (at least given the current count statistics) single peaked. For two pulsars, there are hints for a double-peaked structure in the light curves. The shapes of the observed light curves of this group of pulsars are discussed in the light of models for which the emission originates from high up in the magnetosphere. The observed phases of the γ-ray light curves are, in general, consistent with those predicted by high-altitude models, although we speculate that the γ-ray emission of PSR J0659+1414, possibly featuring the softest spectrum of all Fermi pulsars coupled with a very low efficiency, arises from relatively low down in the magnetosphere. High-quality radio polarization data are available showing that all but one have a high degree of linear polarization. This allows us to place some constraints on the viewing geometry and aids the comparison of the γ-ray light curves with high-energy beam models