306 research outputs found
Confirmatory factor analysis of the Test of Performance Strategies (TOPS) among adolescent athletes
The aim of the present study was to examine the factorial validity of the Test of Performance Strategies (TOPS; Thomas et al., 1999) among adolescent athletes using confirmatory factor analysis. The TOPS was designed to assess eight psychological strategies used in competition (i.e. activation, automaticity, emotional control, goal-setting, imagery, negative thinking, relaxation and self-talk,) and eight used in practice (the same strategies except negative thinking is replaced by attentional control). National-level athletes (n = 584) completed the 64-item TOPS during training camps. Fit indices provided partial support for the overall measurement model for the competition items (robust comparative fit index = 0.92, Tucker-Lewis index = 0.88, root mean square error of approximation = 0.05) but minimal support for the training items (robust comparative fit index = 0.86, Tucker-Lewis index = 0.81, root mean square error of approximation = 0.06). For the competition items, the automaticity, goal-setting, relaxation and self-talk scales showed good fit, whereas the activation, emotional control, imagery and negative thinking scales did not. For the practice items, the attentional control, emotional control, goal-setting, imagery and self-talk scales showed good fit, whereas the activation, automaticity and relaxation scales did not. Overall, it appears that the factorial validity of the TOPS for use with adolescents is questionable at present and further development is required
Characterization of Polyphosphoesters by Fourier Transform Ion Cyclotron Resonance Mass Spectrometry
FT-ICR mass spectrometry, together with collision-induced dissociation and electron capture dissociation, has been used to characterize the polyphosphoester poly[1,4-bis(hydroxyethyl)terephthalate-alt-ethyloxyphosphate] and its degradation products. Three degradation pathways
were elucidated: hydrolysis of the phosphate–[1,4-bis(hydroxyethyl)terephthalate]bonds; hydrolysis of the phosphate–ethoxy bonds; and hydrolysis of the ethyl–terephthalate bonds. The dominant degradation reactions were those that involved the phosphate groups. This work constitutes the first application of mass spectrometry to the characterization of polyphosphoesters and demonstrates the suitability of high mass accuracy FT-ICR mass spectrometry, with CID and ECD, for the structural analysis of polyphosphoesters and their degradation products
Modified Thomson spectrometer design for high energy, multi-species ion sources
A modification to the standard Thomson parabola spectrometer is discussed, which is designed to measure high energy (tens of MeV/nucleon), broad bandwidth spectra of multi-species ions accelerated by intense laser plasma interactions. It is proposed to implement a pair of extended, trapezoidal shaped electric plates, which will not only resolve ion traces at high energies, but will also retain the lower energy part of the spectrum. While a longer (along the axis of the undeflected ion beam direction) electric plate design provides effective charge state separation at the high energy end of the spectrum, the proposed new trapezoidal shape will enable the low energy ions to reach the detector, which would have been clipped or blocked by simply extending the rectangular plates to enhance the electrostatic deflection
Predicting swimming performance using state anxiety
Competitive state anxiety is a common response to stressful competitive sports situations that could affect athletic performance. The effects of state anxiety on swimming performance need further inquiry. The aim of the study was to determine the component of state anxiety that best predicts swimming performance. A quantitative, cross-sectional study design that made use of the Competitive State Anxiety Inventory-2 to measure precompetitive state anxiety was used. A total of 61 male high school swimmers whose age ranged between 14 and 19 years (M = 16.16, standard deviation = 1.66 years) completed the Competitive State Anxiety Inventory-2 1 hr before competing in a 50-m individual swimming event. Performance was evaluated using finishing position. Due to the relatively short duration of the 50-m event, the available literature would suggest that Somatic Anxiety would have a greater effect on Performance - there is not enough time to allow cognitive anxiety to have a detrimental impact on performance. Thus, it was hypothesized that somatic rather than cognitive anxiety will best predict swimming performance. It emerged that both cognitive (b =.787; p <.001) and somatic anxieties (b =.840; p <.001) can independently predict swimming performance. However, when both cognitive and somatic anxieties were regressed onto swimming performance, somatic anxiety partially dominated cognitive anxiety (b =.626; p <.001) and became the significant predictor of swimming performance. It is recommended that swimmers and swimming coaches make use of specific intervention strategies that eradicate the detrimental effects of somatic anxiety immediately before competition.IS
The Golden Meteorite Fall: Fireball Trajectory, Orbit and Meteorite Characterization
The Golden (British Columbia, Canada) meteorite fall occurred on Oct 4, 2021
at 0534 UT with the first recovered fragment (1.3 kg) landing on an occupied
bed. The meteorite is an unbrecciated, low-shock (S2) ordinary chondrite of
intermediate composition, typed as an L/LL5. From noble gas measurements the
cosmic ray exposure age is 25 Ma while gas retention ages are all >2 Ga.
Short-lived radionuclides and noble gas measurements of the pre-atmospheric
size overlap with estimates from infrasound and lightcurve modelling producing
a preferred pre-atmospheric mass of 70-200 kg. The orbit of Golden has a high
inclination (23.5 degs) and is consistent with delivery from the inner main
belt. The highest probability (60%) of an origin is from the Hungaria group. We
propose that Golden may originate among the background S-type asteroids found
interspersed in the Hungaria region. The current collection of 18 L and LL
chondrite orbits shows a strong preference for origins in the inner main belt,
suggesting multiple parent bodies may be required to explain the diversity in
CRE ages and shock states.Comment: 92 Pages, 20 Tables, 21 Figures, plus 3 appendices, accepted in
Meteoritics and Planetary Science Oct 26 202
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