1,961 research outputs found
Comparisons of Perceived Training Doses in Champion Collegiate-Level Male and Female Cross-country Runners and Coaches over the Course of a Competitive Season
Background: Session rating of perceived exertion (sRPE) is a practical tool for coaches to assess internal training load of their athletes. In a sport like cross-country running, that is individual in nature, but has a team training and competition component, information about the association between external and internal load is lacking. Furthermore, there is a need for studies that examine perception of training doses across multiple training cycles including the competitive season as well as between male and female athletes.
Methods: Session RPE, duration, and training load (TLRPE = sRPE Ă duration) of 25 highly trained male and female cross-country runners and their coaches were recorded for every training session (110 days) throughout a collegiate cross-country season. Intensity (sRPE), duration, and TLRPE were compared between coaches and runners by gender separately. Training sessions were also analyzed by those intended by the coaches to be easy, moderate, and hard as well as by training period.
Results: Data from 3024 training sessions were collected, 62% of which were considered âeasy,â 18% âmoderate,â and 20% âhard.â Men and women rated coach-intended easy sessions significantly harder during each month of the season (effect size (ES) \u3e 2.9, p \u3c 0.0001). Men rated moderate intensity sessions significantly higher than coaches (ES â„ 1.0, p †0.002), whereas females rated hard intensity sessions significantly lower than coaches (ES \u3e 0.5, p \u3c 0.008). There was no difference between males and coachâs hard sessions (ES \u3c 0.07, p \u3e 0.05) or females and coachâs moderate sessions (ES \u3c 0.18, p \u3e 0.05). Training intensity and TLRPE tended to increase throughout the season (p \u3e 0.05), with a significant increase in moderate and hard intensity sessions in the last training period (p \u3c 0.001).
Conclusions: The results indicate the male and female cross-country runners tend to regress to moderate intensity training throughout the cross-country season. Given the success of the athletes in this study, these results show how a simple system for monitoring training such as the sRPE method may improve control of training variables and provide a useful tool for coaches to evaluate training load placed on athletes in a simple, responsive way
Physiological strain of firefighters exposed to a live firefighting exercise
Department Head: Richard Gay Israel.2009 Spring.Includes bibliographical references (pages 71-80).The physiological demands of occupations such as live urban or wildland firefighting are an important determinant of occupational safety, and can inform decisions about employee recruitment, screening, and training. To this end, the present study describes the physiological strain which attends live burn exercises in an urban firefighter academy. Fourteen firefighters from the Northern Colorado Fire Consortium Fire Academy participated in this investigation. The firefighter cadetsâ clinical characteristics were as follows (mean ± SD): age 28.8 ± 5.7 years; height 1.8 ± 0.1 m; mass 83.8 ± 12.9 kg; body mass index (BMI) 26.3 ± 3.0; maximal aerobic capacity 45.0 ± 4.4 ml/kg/min, 3.77 ± 0.6 L/min. Participants were studied during two live burn sessions separated by four days. The mean (± SD) duration of fire exposures was 9.6 ± 1.5 and 9.32 ± 2.6 minutes for day one and two, respectively. The pre-burn heart rates were 92.7 ± 18.0 bpm and 96.4 ± 13.8 bpm in days one and two, respectively. The mean pre-burn blood pressures were 117/68 ± 18.7/9.1 and 122/76 ± 11.0/8.9, respectively. The mean pre-burn blood lactate was 3.3 ± 1.9 mmol/L on day one and 2.7 ± 1.0 mmol/L on day two
Co-Localization of Basal and Proliferative Cells in the Murine Main Olfactory Epithelium and Vomeronasal Organ after Injury with Cyclophosphamide
ABSTRACT
In humans, advanced malignancies are often targeted with broad-spectrum cytotoxic drugs that engender several detrimental side effects, in addition to their primary usage for eradicating cancerous cells. One of the lesser-researched of these effects, histological distortion of the olfactory system impedes a patient\u27s ability to smell, perceive flavor, and ultimately may interfere with their nutritional intake and recovery from chemotherapy. Recent studies have indicated that cytotoxic drugs can damage gustatory epithelia immediately following administration (Mukherjee & Delay, 2011, 2013). We sought to observe the histological effects that cyclophosphamide (CYP), one of the oldest and most popular alkylating antineoplastic agents, may have on the murine main olfactory epithelium (MOE) and vomeronasal organ (VNO). We utilized two immunohistochemical antibodies to label cells in the olfactory epithelia: anti-Ki67, a marker strictly associated with cell proliferation; and, anti-Keratin 5, a marker for the cytoskeleton of horizontal basal cells. Twenty-eight C57BL/6 mice were administered a single intraperitoneal injection of CYP (75 mg/kg), while 20 control mice were administered saline, all at approximately seven weeks of age. Mice were euthanized at days one, two, six, 14, 30, and 45 post injection; subsequently, they were perfused with 4% paraformaldehyde, decalcified, cryoprotected, cryosectioned, and incubated with anti-Ki67 and anti-Keratin 5 antibodies, sequentially. Quantification results by fluorescent imaging of labeled sections revealed a significant decrease in the number of proliferative cells in the MOE and VNO of CYP-injected mice within the first 10 days post injection, followed by a compensatory period of increased cell proliferation through day 45 post injection, compared to saline-injected mice. Co-localization of horizontal basal cells and proliferative cells in the MOE and VNO of CYP-injected mice was significantly amplified at approximately 14 and 45 days post injection, respectively, compared to saline-injected mice. Our results suggest that administration of CYP can rapidly depress the populations of proliferative cells in the murine MOE and VNO; consequently, horizontal basal cells may afford restoration of the proliferative cell populations in the murine MOE and VNO, 14 to 45 days post injection, respectively
Metabolic Demands of ElliptiGO Cycling Compared to Running
ElliptiGO cycling is a new form of exercise; the metabolic demands, however, have not been investigated. In a cross-over design, 17 runners completed 5Ă3 min stages while either cycling on a stationary ElliptiGO or running on a treadmill during which HR, RPE, and expired gases were collected using a portable metabolic analyzer. Subjects increased one gear or 1 mph every 3 min during cycling or running respectively. A 10 min recovery between modes of exercise was given. For each testing intensity, metabolic demand (VO2), HR, and VE was significantly higher during running (p \u3c 0.05), however the RPE for each intensity was similar (p \u3e 0.05). There was a linear relationship between speed and VO2 but the relationship for running had a steeper slope compared to the ElliptiGO. As a result, the ElliptiGO speed that was equivalent to the VO2 of each running speed increased at a greater rate. When matched for VO2, the HR, VE, and RPE were actually higher for ElliptiGO compared to running
Dynamical Henneaux-Teitelboim Gravity
We consider a modified gravity model which we call "dynamical
Henneaux-Teitelboim gravity" because of its close relationship with the
Henneaux-Teitelboim formulation of unimodular gravity. The latter is a fully
diffeomorphism-invariant formulation of unimodular gravity, where full
diffeomorphism invariance is achieved by introducing two additional
non-dynamical fields: a scalar, which plays the role of a cosmological
constant, and a three-form whose exterior derivative is the spacetime volume
element. Dynamical Henneaux-Teitelboim gravity is a generalization of this
model that includes kinetic terms for both the scalar and the three-form with
arbitrary couplings. We study the field equations for the cases of spherically
symmetric and homogeneous, isotropic configurations. In the spherically
symmetric case, we solve the field equations analytically for small values of
the coupling to obtain an approximate black hole solution. In the homogeneous
and isotropic case, we perturb around de Sitter space to find an approximate
cosmological background for our model.Comment: 10 pages, 2 figure
Designing dynamically corrected gates robust to multiple noise sources using geometric space curves
Noise-induced gate errors remain one of the main obstacles to realizing a
broad range of quantum information technologies. Dynamical error suppression
using carefully designed control schemes is critical for overcoming this
challenge. Such schemes must be able to correct against multiple noise sources
simultaneously afflicting a qubit in order to reach error correction
thresholds. Here, we present a general framework for designing control fields
that simultaneous suppress both noise in the fields themselves as well as
transverse dephasing noise. Using the recently developed Space Curve Quantum
Control formalism, in which robust quantum evolution is mapped to closed
geometric curves in a multidimensional Euclidean space, we derive necessary and
sufficient conditions that guarantee the cancellation of both types of noise to
leading order. We present several techniques for solving these conditions and
provide explicit examples of error-resistant control fields. Our work also
sheds light on the relation between holonomic evolution and the suppression of
control field errors.Comment: 12 pages, 4 figure
Production of crystallizable human chymase from a Bacillus subtilis system
AbstractA Bacillus subtilis strain deficient in seven extracellular proteases was used to produce human mast cell chymase and is a viable expression system for serine proteases and other classes of proteins. Chymase is produced at 0.3â0.5 mg/l and is purified by three chromatography steps. Two crystal forms of PMSF-treated chymase were optimized. The first is C2 with a=47.94 Ă
, b=85.23 Ă
, c=174.18 Ă
, ÎČ=96.74°, and diffracts to at least 2.1 Ă
, while the second is P212121, with cell dimensions a=43.93 Ă
, b=58.16 Ă
, and c=86.09 Ă
, and a diffraction limit of approximately 1.9 Ă
. The first crystal form has either three or four molecules/asymmetric unit, while the second has one molecule/asymmetric unit
A New Automatic Method to Identify Galaxy Mergers I. Description and Application to the STAGES Survey
We present an automatic method to identify galaxy mergers using the
morphological information contained in the residual images of galaxies after
the subtraction of a Sersic model. The removal of the bulk signal from the host
galaxy light is done with the aim of detecting the fainter minor mergers. The
specific morphological parameters that are used in the merger diagnostic
suggested here are the Residual Flux Fraction and the asymmetry of the
residuals. The new diagnostic has been calibrated and optimized so that the
resulting merger sample is very complete. However, the contamination by
non-mergers is also high. If the same optimization method is adopted for
combinations of other structural parameters such as the CAS system, the merger
indicator we introduce yields merger samples of equal or higher statistical
quality than the samples obtained through the use of other structural
parameters. We explore the ability of the method presented here to select minor
mergers by identifying a sample of visually classified mergers that would not
have been picked up by the use of the CAS system, when using its usual limits.
Given the low prevalence of mergers among the general population of galaxies
and the optimization used here, we find that the merger diagnostic introduced
in this work is best used as a negative merger test, i.e., it is very effective
at selecting non-merging galaxies. As with all the currently available
automatic methods, the sample of merger candidates selected is contaminated by
non-mergers, and further steps are needed to produce a clean sample. This
merger diagnostic has been developed using the HST/ACS F606W images of the
A901/02 cluster (z=0.165) obtained by the STAGES team. In particular, we have
focused on a mass and magnitude limited sample (log M/M_{O}>9.0,
R_{Vega}<23.5mag)) which includes 905 cluster galaxies and 655 field galaxies
of all morphological types.Comment: 25 pages, 14 figures, 4 tables. To appear in MNRA
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