182,046 research outputs found
Reporting doping in sport: national level athletes' perceptions of their role in doping prevention.
This paper qualitatively explores national level athletes' willingness to report doping in sport. Following ethical approval, semi-structured interviews were conducted with nine national level athletes from rugby league (n = 5) and track and field athletics (n = 4). Thematic analysis established the main themes within the data. Contextual differences existed around the role that athletes perceived they would play if they became aware of doping. Specifically, track and field athletes would adopt the role of a whistle-blower and report individuals who were doping in their sport. In comparison, the rugby league players highlighted a moral dilemma. Despite disagreeing with their teammates' actions, the players would adhere to a code of silence and refrain from reporting doping. Taking these findings into account, prevention programs might focus on changing broader group and community norms around doping. In doing so, community members' receptivity to prevention messages may increase. Moreover, developing skills to intervene (e.g., speaking out against social norms that support doping behavior) or increasing awareness of reporting lines could enhance community responsibility for doping prevention. In sum, the findings highlight the need to consider the context of sport and emphasize that a one-size-fits-all approach to anti-doping is problematic
Minority carrier diffusion lengths and mobilities in low-doped n-InGaAs for focal plane array applications
The hole diffusion length in n-InGaAs is extracted for two samples of
different doping concentrations using a set of long and thin diffused junction
diodes separated by various distances on the order of the diffusion length. The
methodology is described, including the ensuing analysis which yields diffusion
lengths between 70 - 85 um at room temperature for doping concentrations in the
range of 5 - 9 x 10^15 cm-3. The analysis also provides insight into the
minority carrier mobility which is a parameter not commonly reported in the
literature. Hole mobilities on the order of 500 - 750 cm2/Vs are reported for
the aforementioned doping range, which are comparable albeit longer than the
majority hole mobility for the same doping magnitude in p-InGaAs. A radiative
recombination coefficient of (0.5-0.2)x10^-10 cm^-3s^-1 is also extracted from
the ensuing analysis for an InGaAs thickness of 2.7 um. Preliminary evidence is
also given for both heavy and light hole diffusion. The dark current of
InP/InGaAs p-i-n photodetectors with 25 and 15 um pitches are then calibrated
to device simulations and correlated to the extracted diffusion lengths and
doping concentrations. An effective Shockley-Read-Hall lifetime of between
90-200 us provides the best fit to the dark current of these structures.Comment: 9 pages, 5 figure
Using the prototype willingness model to predict doping in sport.
To enable preventive measures to be designed, it is important to identify modifiable distal and proximal factors underlying doping behavior. This study investigated aspects of the prototype willingness model in relation to doping. A cross-sectional study was conducted involving 729 competitive athletes. Following ethical approval, athletes (mean age = 28.8 ± 10.1 years; 63% male) completed an online questionnaire, which assessed doping-related attitudes, norms, prototype perceptions, outcome expectancies, and behavioral willingness. Using hierarchical multiple regression analysis, 54.4% of the total variance in willingness to dope was explained. Specifically, past doping, attitudes, and favorability of performance enhancing substance user prototypes were the strongest unique predictors of willingness to dope. Athletes appeared most willing to dope if they were to suffer an injury, a dip in performance, or think others are doping and getting away with it. National-level athletes displayed significantly greater willingness to dope (Kruskal-Wallis γ2 = 35.9, P < 0.001) and perceived themselves as significantly more similar to a doper (Kruskal-Wallis γ2 = 13.4, P = 0.004) than athletes competing at any other level. The findings highlight the importance of extending anti-doping provision beyond elite-level sport and the need to target athletes' doping-related perceptions
Sulfur doping effects on the electronic and geometric structures of graphitic carbon nitride photocatalyst: insights from first principles
We present here results of our first principles studies of the sulfur doping
effects on the electronic and geometric structures of graphitic carbon nitride
(g-C3N4). Using the Ab initio thermodynamics approach combined with some
kinetic analysis, we reveal the favorable S-doping configurations By analyzing
the valence charge densities of the doped and un-doped systems, we find that
sulfur partially donates its px- and py- electrons to the system with some back
donation to the S pz-states. To obtain accurate description of the excited
electronic states, we calculate the electronic structure of the systems using
the GW method. The band gap width calculated for g-C3N4 is found to be equal to
2.7 eV that is in agreement with experiment. We find the S doping to cause a
significant narrowing the gap. Furthermore, the electronic states just above
the gap become occupied upon doping that makes the material a conductor.
Analysis of the projected local densities of states provides insight into the
mechanism underlying such dramatic changes in the electronic structure of
g-C3N4 upon the S doping. Based on our results, we propose a possible
explanation for the S doping effect on the photo-catalytic properties of g-C3N4
observed in the experiments
Structural, magnetic and transport properties in the Cu-doped manganites La0.85Te0.15Mn1-xCuxO3 (0 \leq x \leq 0.20)
The effect of Cu-doping at Mn-site on structural, magnetic and transport
properties in electron-doped manganites La0.85Te0.15Mn1-xCuxO3 has been
investigated. Based on the analysis of structural parameter variations, the
valence state of the Cu ion in Cu-doped manganites is suggested to be +2. All
samples undergo the paramagnetic-ferromagnetic (PM-FM) phase transition. The
Curie temperature decreases and the transition becomes broader with increasing
Cu-doping level, in contrast, the magnetization magnitude of Cu-doping samples
at low temperatures increase as x \leq 0.15. The insulator-metal (I-M)
transition moves to lower temperatures with increasing Cu-doping content and
disappears as x > 0.1. In addition, the higher temperature resistivity r peak
in double-peak-like r(T) curves observed in no Cu-doping sample is completely
suppressed as Cu-doping level x = 0.1 and r(T) curve only shows single I-M
transition at the low temperature well below . The results are discussed
according to the change of magnetic exchange interaction caused by Cu-doping.Comment: 17 pages, 5 figures. Phys.Rev.B (to be published
Asymmetry of Superconductivity in Hole- and Electron-doped Cuprates: Explanation within Two-Particle Self-Consistent Analysis for the Three-Band Model
In the hole-doped cuprate superconductors, the superconducting transition
temperature exhibits a dome-like feature against the doping rate. By
contrast, recent experiments reveal that in the electron-doped systems
monotonically increases as the doping is reduced, at least up to a very small
doping rate. Here we show that this asymmetry is reproduced by performing a
two-particle self-consistent analysis for the three-band model of the CuO
plane. This is explained as a combined effect of the intrinsic electron-hole
asymmetry in systems comprising Cu3 and O2 orbitals and the
band-filling-dependent vertex correction.Comment: 5 pages, 5 figures, 2 table
Perfectionism and attitudes towards doping in junior athletes
Recent theory and research suggest that perfectionism is a personal factor contributing to athletes’ vulnerability to doping (using banned substances/drugs to enhance sporting performance). So far, however, no study has examined what aspects of perfectionism suggest a vulnerability in junior athletes. Employing a cross-sectional design, this study examined perfectionism and attitudes towards doping in 129 male junior athletes (mean age 17.3 years) differentiating four aspects of perfectionism: perfectionistic strivings, perfectionistic concerns, parental pressure to be perfect, and coach pressure to be perfect. In the bivariate correlations, only parental pressure showed a positive relationship with positive doping attitudes. In a multiple regression analysis controlling for the overlap between the four aspects, perfectionistic strivings additionally showed a negative relationship. Moreover, a structural equation model examining the relationships between all variables suggested that coach pressure had a negative indirect effect on attitudes towards doping via perfectionistic strivings. The findings indicate that perceived parental pressure to be perfect may be a factor contributing to junior athletes’ vulnerability to doping, whereas perfectionistic strivings may be a protective factor
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