2,026 research outputs found
PRM51 From Clinical Trial to Real-World Evidence: A Systematic Approach to Identifying Data Sources for Observational Research
Edifici industrial de dos cossos de planta baixa i tres plantes pis acabades amb mansarda. Destaca el nombre i dimensions de les obertures que permeten una gran entrada de llum a l'interior i l'amplitud de les plantes diàfanes.Digitalitzat per Tecnodo
The Relationship Between Aerobic and Anaerobic Performance in Recreational Runners
International Journal of Exercise Science 9(5): 625-634, 2016. Research has indicated that combined aerobic and anaerobic training (concurrent training) may improve aerobic performance greater than aerobic training alone. The purpose of this investigation was to establish any associations between aerobic and anaerobic performance. Eleven participants (n = 11, age = 34.1 ± 13 years, VO2max = 58.4 ± 7.8) volunteered for this study. Participants were asked for endurance training experience (4.7 ± 3.7 years) and resistance training experience (4.1 ± 4.6 years). To meet training status, participants were to have a VO2max in the 80th percentile as per ACSM guidelines. The Bruce treadmill test was used to measure aerobic performance. In order to measure anaerobic performance, several tests were completed utilizing a force platform. A Pearson Product R Correlation Coefficient was calculated to determine correlations between variables. The results show significant correlation between VO2max and RFD (r = 0.68). Further analyses utilizing Cohen’s effect size indicated a strong association between VO2max and peak force, as well as running efficiency and peak power, relative peak power, and power endurance. These results indicate an existing possibility that anaerobic performance measures such as RFD may have a positive relationship with aerobic performance measures such as VO2max. Therefore, it may be beneficial to integrate specific training components which focus on improving RFD as a method of improving running performance
An Integrated Exploration of the Contextual, Relational, and Individual Factors that Impact High School Completion among African Americans
African American students are consistently reported as having among the lowest high school graduation rates when compared to other races (U.S. Department of Education, 2018). While many studies have sought to explore the potential risks of high school dropout, the intention of this study is to examine the factors that support the exemplary resilience of those students who do complete high school. The present study adopts the framework of García Coll et al.’s, (1996) integrative model of developmental competencies in minority children, as it seeks to identity whether and how contextual (spiritual, educational, cultural); relational (caregiver psychological and physical relationship quality); and individual factors (academic self-efficacy) influence African American individuals to complete high school. To analyze the implications of the research questions, I propose the use of a double moderation and moderated moderation approach to determine the influence of the predictors on high school completion. The findings of this study provided partial support for the associated hypotheses. Specifically, although the dimension of contextual resilience did not emerge as a unique predictor of African American students’ high school completion, the interaction between contextual factors and relational factors revealed that at higher levels of relational factors, increased contextual factors are associated with an increased likelihood of high school completion. Importantly, the findings also suggest that at lower levels of relational factors, increased contextual factors are associated with a decreased likelihood of high school completion among African American students. Implications and future directions are discussed
The use endocrine markers to predict and monitor performance in strengh [sic] and power activities
Hormones are typically considered to be chemical messengers, which are designed to be released from specific cells where they are carried to their target tissues for binding to receptors. It is this binding of a hormone molecule to its specific receptor which allows for an action to occur (Hadley and Levine 2006). Testosterone is the predominant androgen in the majority of mammalian species and is largely responsible for regulation of reproduction and maintenance of sexual function. In addition, in adult mammals, T has multiple other roles including the growth of muscle and bone, hematopoesis, blood coagulation, development and regulation of plasma lipids, protein and carbohydrate metabolism, and cognitive function (Bhasin, 2005). Cortisol has typically been thought of as a suppressor of the immune system and an anti-inflammatory agent as it is an inducer of cellular apoptosis. In research where corticosteroids were given intravenously to humans, responses of apoptosis of T and B cells were noted (Cohen and Duke 1984). Testosterone and C as well as other hormones have received significant attention in recent years by several researchers who have proposed a link between these hormones and performance, adaptive capability, and overtraining syndrome (Kraemer & Ratamass, 2005). The use of T to C ratio (T/C) has gained some popularity in recent years as a method to monitor anabolic/catabolic state in athletes, and to predict athletic performance and/or overtraining. There is a growing body of evidence that T/C may be useful in monitoring training stress and physiological phenomenon, however, the relationship between these variables and any actual physical performance has not been solidly established at this time
Inhomogeneous isospin distribution in the reactions of 28Si + 112Sn and 124Sn at 30 and 50 MeV/nucleon
We have created quasiprojectiles of varying isospin via peripheral reactions
of 28Si + 112Sn and 124Sn at 30 and 50 MeV/nucleon. The quasiprojectiles have
been reconstructed from completely isotopically identified fragments. The
difference in N/Z of the reconstructed quasiprojectiles allows the
investigation of the disassembly as a function of the isospin of the
fragmenting system. The isobaric yield ratio 3H/3He depends strongly on N/Z
ratio of quasiprojectiles. The dependences of mean fragment multiplicity and
mean N/Z ratio of the fragments on N/Z ratio of the quasiprojectile are
different for light charged particles and intermediate mass fragments.
Observation of a different N/Z ratio of light charged particles and
intermediate mass fragments is consistent with an inhomogeneous distribution of
isospin in the fragmenting system.Comment: 5 pages, 4 Postscript figures, RevTe
Critical Behavior in Light Nuclear Systems: Experimental Aspects
An extensive experimental survey of the features of the disassembly of a
small quasi-projectile system with 36, produced in the reactions of 47
MeV/nucleon Ar + Al, Ti and Ni, has been carried
out. Nuclei in the excitation energy range of 1-9 MeV/u have been investigated
employing a new method to reconstruct the quasi-projectile source. At an
excitation energy 5.6 MeV/nucleon many observables indicate the presence
of maximal fluctuations in the de-excitation processes. The fragment
topological structure shows that the rank sorted fragments obey Zipf's law at
the point of largest fluctuations providing another indication of a liquid gas
phase transition. The caloric curve for this system shows a monotonic increase
of temperature with excitation energy and no apparent plateau. The temperature
at the point of maximal fluctuations is MeV. Taking this
temperature as the critical temperature and employing the caloric curve
information we have extracted the critical exponents , and
from the data. Their values are also consistent with the values of the
universality class of the liquid gas phase transition. Taken together, this
body of evidence strongly suggests a phase change in an equilibrated mesoscopic
system at, or extremely close to, the critical point.Comment: Physical Review C, in press; some discussions about the validity of
excitation energy in peripheral collisions have been added; 24 pages and 32
figures; longer abstract in the preprin
Thermal excitation of heavy nuclei with 5-15 GeV/c antiproton, proton and pion beams
Excitation-energy distributions have been derived from measurements of
5.0-14.6 GeV/c antiproton, proton and pion reactions with Au target
nuclei, using the ISiS 4 detector array. The maximum probability for
producing high excitation-energy events is found for the antiproton beam
relative to other hadrons, He and beams from LEAR. For protons
and pions, the excitation-energy distributions are nearly independent of hadron
type and beam momentum above about 8 GeV/c. The excitation energy enhancement
for beams and the saturation effect are qualitatively consistent with
intranuclear cascade code predictions. For all systems studied, maximum cluster
sizes are observed for residues with E*/A 6 MeV.Comment: 14 pages including 5 figures and 1 table. Accepted in Physics Letter
B. also available at http://nuchem.iucf.indiana.edu
Properties of the Initial Participant Matter Interaction Zone in Near Fermi-Energy Heavy Ion Collisions
The sizes, temperatures and free neutron to proton ratios of the initial
interaction zones produced in the collisions of 40 MeV/nucleon Ar +
Sn and 55 MeV/nucleonAl + Sn are derived using total
detected neutron plus charged particle multiplicity as a measure of the impact
parameter range and number of participant nucleons. The size of the initial
interaction zone, determined from a coalescence model analysis, increases
significantly with decreasing impact parameter. The temperatures and free
neutron to proton ratios in the interaction zones are relatively similar for
different impact parameter ranges and evolve in a similar fashion.Comment: 7 pages, 8 figure
Tracing the Evolution of Temperature in Near Fermi Energy Heavy Ion Collisions
The kinetic energy variation of emitted light clusters has been employed as a
clock to explore the time evolution of the temperature for thermalizing
composite systems produced in the reactions of 26A, 35A and 47A MeV Zn
with Ni, Mo and Au. For each system investigated, the
double isotope ratio temperature curve exhibits a high maximum apparent
temperature, in the range of 10-25 MeV, at high ejectile velocity. These
maximum values increase with increasing projectile energy and decrease with
increasing target mass. The time at which the maximum in the temperature curve
is reached ranges from 80 to 130 fm/c after contact. For each different target,
the subsequent cooling curves for all three projectile energies are quite
similar. Temperatures comparable to those of limiting temperature systematics
are reached 30 to 40 fm/c after the times corresponding to the maxima, at a
time when AMD-V transport model calculations predict entry into the final
evaporative or fragmentation stage of de-excitation of the hot composite
systems. Evidence for the establishment of thermal and chemical equilibrium is
discussed.Comment: 9 pages, 5 figure
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