108 research outputs found
Perceptual and Contextual Sources of Athletic Training Confidence: The Transition to Professional Entry Level Masterâs Programs
Introduction: The shift of athletic training education from undergraduate degrees to professional masterâs degrees and the prominence of computer-based credentialing may impact the hands-on experiences beneficial for developing confidence in athletic training competency domains. Health care provider confidence is critical for clinical skill development, performance and enhancing patient care. Purpose: To examine domain specific efficacy, its sources, learning contexts (i.e., classroom, laboratory, clinical settings) and clinical characteristics by program types. Method: Descriptive, cross-sectional design where 178 Athletic Trainers (AT; age 24.25 + 3.76, n = 72 male, n = 106 female) participated in the study (Masterâs Program (MP) = 38; Undergraduate Program (UG) = 140). A questionnaire examining athletic training confidence was administered throughout multiple universities with accredited athletic training programs. Background characteristics, certification exam attempts, and programmatic characteristics were also ascertained. Results: Clinical settings were similar in both program types and there were few differences in domain-specific efficacy. Imaginal experiences, verbal persuasion and emotional states sources of efficacy differentiated masterâs from undergraduate students. Conclusions: Sources of efficacy (e.g. vicarious experiences) occur naturally in athletic training educational settings; however, these sources need to be utilized. Educators should be informed about efficacy sources and devise strategies targeting each source for implementation across evolving learning contexts
Social physique anxiety and physical activity in early adolescent girls : the influence of maturation and physical activity motives
This study considered the influence of maturation on social physique anxiety (SPA), the relationship between SPA and current and future physical activity (PA) levels and the influence of motives for physical activity on this relationship in early adolescent girls (n=162; mean age=11.80±0.33 years). Participants completed the Pubertal Development Scale, the modified Social Physique Anxiety Scale and the Motives for Physical Activity Scale at baseline and the Physical Activity Questionnaire for Older Children at baseline and 6 months later. The girls became less active across the 6 months and girls in the early stages of maturation had significantly lower SPA than the girls in the middle and late stages of maturation. SPA was not related to current or future physical activity in the sample as a whole. Cluster analysis identified four groups with different motive profiles and the High Appearance and Fitness group demonstrated a moderate negative relationship between SPA and PA at phase 1, whereas the other groups did not. These findings indicate that SPA may increase with maturation and the relationship between SPA and PA is dependent on reasons for being active. For girls who are motivated to be active primarily by body-related reasons SPA is likely to lead to lower levels of PA
Theory of electrical spin injection: Tunnel contacts as a solution of the conductivity mismatch problem
Theory of electrical spin injection from a ferromagnetic (FM) metal into a
normal (N) conductor is presented. We show that tunnel contacts (T) can
dramatically increase spin injection and solve the problem of the mismatch in
the conductivities of a FM metal and a semiconductor microstructure. We also
present explicit expressions for the spin-valve resistance of FM-T-N- and
FM-T-N-T-FM-junctions with tunnel contacts at the interfaces and show that the
resistance includes both positive and negative contributions (Kapitza
resistance and injection conductivity, respectively).Comment: 4 pages, to appear in Phys. Rev. B (rapid communications
Fit to Play? Health-Related Fitness Levels of Youth Athletes: A Pilot Study
A recent National Strength and Conditioning Association position statement suggests that many youth are not prepared for the physical demands of sport. The purpose of this study was to compare health-related fitness (HRF) of youth athletes with normative findings from the general population. We recruited 136 athletes (63 male and 73 female athletes) aged 11-19 (16.01 ± 1.35) years and collected HRF (body composition, cardiorespiratory endurance, musculoskeletal strength and endurance). Results were categorized based on FITNESSGRAMŸ standards and compared with Canadian youth general population normative data. Most male athletes were classified as "needs improvement" for cardiorespiratory and muscular endurance, and body mass index (BMI). Conversely, most female athletes were at or above the "healthy fitness zone" for all measures. Male athletes at both age groups (11-14, 15-19; p < 0.001) and female athletes aged 11-14 (p < 0.05) demonstrated lower cardiorespiratory endurance compared with Canadian general population. Female athletes (both age groups) demonstrated greater muscular strength, and male athletes (age, 15-19 years) demonstrated lower BMI than the Canadian general population. The results are concerning as male athletes demonstrated poorer HRF compared with the general population. Although most female athletes were within healthy ranges, a portion of them were still at risk. Considering the demands sport places on the body, evaluating HRF is paramount for performance and injury prevention but more importantly for overall health. Youth sport and strength coaches should evaluate and aim to enhance HRF, as participation in sport does not guarantee adequate HRF. Promoting long-term athletic development and life-long health should be a priority in youth
Functional Movement Screen(TM) in Youth Sport Participants: Evaluating the Proficiency Barrier for Injury
Background & Purpose: The number of youth participating in sport increases yearly; however, the evaluation of youthsâ movement
ability and preparedness for sport remains inadequate or neglected. The Functional Movement Screen (FMSâą) is an assessment
of an individualâs movement quality that has been utilized to evaluate risk of injury in collegiate and professional sport;
however, there is minimal support regarding the predictive value of the screen in youth sport. The purpose of this study was to
evaluate the mean and distribution of FMSâą performance in sport participants age 11-18, and to evaluate the existence of a composite
FMSâą score proficiency barrier to predict injury risk.
Study Design: Prospective cohort study.
Methods: One hundred, thirty-six participants (63 male, 73 female) age 11 to 18 years (16.01 + 1.35) were recruited from local
schools and sport organizations. The FMSâą was administered prior to each participantâs competitive season and scored by researchers
who demonstrated reliability in assessments derived from the screen (Îșw = 0.70 to 1). Injury data were collected by the participantsâ
Athletic Trainer over one season. An injury was defined as any physical insult or harm resulting from sports participation
that required an evaluation from a health professional with time modified or time lost from sport participation.
Results: Females scored significantly higher than males for mean FMSâą composite score (t=14.40; m=12.62; p < 0.001), and on
individual measures including: the hurdle step (t=1.91; m=1.65; p < 0.001), shoulder mobility (t=2.68; m=2.02; p < 0.001), active
straight leg raise (t=2.32; m=1.87; p < 0.001), and the rotary stability components (t=1.91; m=1.65; p < 0.05). Two FMSâą composite
scores (score <14 and <15) significantly increased the odds of injury (OR=2.955). When adjusting for sport, there was no
score relating to increased odds of injury.
Conclusion: Dysfunctional movement as identified by the FMSâą may be related to increased odds of injury during the competitive
season in youth athletes. Consideration of an individualâs movement within the context of their sport is necessary, as each sport
and individual have unique characteristics. Addressing movement dysfunction may aid in injury reduction and potentially improve
sport performance.
Level of Evidence: 1b.
Key Words: Functional movement screen, injury prevention, movement system, movement quality, youth spor
Quasiparticle dynamics in ferromagnetic compounds of the Co-Fe and Ni-Fe systems
We report a theoretical study of the quasiparticle lifetime and the
quasiparticle mean free path caused by inelastic electron-electron scattering
in ferromagnetic compounds of the Co-Fe and Ni-Fe systems. The study is based
on spin-polarized calculations, which are performed within the
approximation for equiatomic and Co- and Ni-rich compounds, as well as for
their constituents. We mainly focus on the spin asymmetry of the quasiparticle
properties, which leads to the spin-filtering effect experimentally observed in
spin-dependent transport of hot electrons and holes in the systems under study.
By comparing with available experimental data on the attenuation length, we
estimate the contribution of the inelastic mean free path to the latter.Comment: 10 pages, 10 figure
Spintronics: Fundamentals and applications
Spintronics, or spin electronics, involves the study of active control and
manipulation of spin degrees of freedom in solid-state systems. This article
reviews the current status of this subject, including both recent advances and
well-established results. The primary focus is on the basic physical principles
underlying the generation of carrier spin polarization, spin dynamics, and
spin-polarized transport in semiconductors and metals. Spin transport differs
from charge transport in that spin is a nonconserved quantity in solids due to
spin-orbit and hyperfine coupling. The authors discuss in detail spin
decoherence mechanisms in metals and semiconductors. Various theories of spin
injection and spin-polarized transport are applied to hybrid structures
relevant to spin-based devices and fundamental studies of materials properties.
Experimental work is reviewed with the emphasis on projected applications, in
which external electric and magnetic fields and illumination by light will be
used to control spin and charge dynamics to create new functionalities not
feasible or ineffective with conventional electronics.Comment: invited review, 36 figures, 900+ references; minor stylistic changes
from the published versio
Graphene-passivated nickel as an oxidation-resistant electrode for spintronics.
We report on graphene-passivated ferromagnetic electrodes (GPFE) for spin devices. GPFE are shown to act as spin-polarized oxidation-resistant electrodes. The direct coating of nickel with few layer graphene through a readily scalable chemical vapor deposition (CVD) process allows the preservation of an unoxidized nickel surface upon air exposure. Fabrication and measurement of complete reference tunneling spin valve structures demonstrate that the GPFE is maintained as a spin polarizer and also that the presence of the graphene coating leads to a specific sign reversal of the magneto-resistance. Hence, this work highlights a novel oxidation-resistant spin source which further unlocks low cost wet chemistry processes for spintronics devices.R.S.W. acknowledges funding from EPSRC
(Doctoral training award). S.H. acknowledges funding from ERC
Grant InsituNANO (Project Reference 279342). P.S. acknowledges
the Institut Universitaire de France for junior fellowship
support. This research was partially supported by the EU FP7
work programme under Grant GRAFOL (Project Reference
285275).This is the accepted manuscript. The final version is available from ACS at http://pubs.acs.org/doi/abs/10.1021/nn304424x
Criminalidade organizada nas prisÔes e os ataques do PCC
The advent of organized crime in Brazilian prisons, especially in the state of SĂŁo Paulo, constitutes the object of this article. The waves of attack unleashed by the Capital's First Command (PCC - Primeiro Comando da Capital), in May 2006, which resulted in countless deaths, brought cities to a halt, and cornered authorities in charge preventing them from applying law and order are the starting as well as reference points taken. The advent of organized criminality is analyzed under the light of determined axes: the international scenario and the Brazilian context, the historical antecedents, the taking root of crime in society and the role of penitentiary public policies.A emergĂȘncia da criminalidade organizada nas prisĂ”es brasileiras, em especial no Estado de SĂŁo Paulo, constitui objeto deste artigo. Tomam-se como ponto de partida e referĂȘncia para anĂĄlise as ondas de ataques desencadeadas pelo Primeiro Comando da Capital (PCC), de maio a agosto de 2006, que resultaram em inĂșmeros mortos, paralisaram cidades e acuaram as autoridades encarregadas de aplicar lei e ordem. A emergĂȘncia da criminalidade organizada Ă© analisada sob eixos determinados: cenĂĄrio internacional e contexto brasileiro, antecedentes histĂłricos, enraizamento do crime na sociedade e papel das polĂticas pĂșblicas penitenciĂĄrias
- âŠ