4,858 research outputs found
A retrospective analysis of trick progression in elite freeskiing and snowboarding
This study offered a first examination of skill development within freeskiing and snowboarding, using semistructured interviews to examine trick progression. Participants were purposefully recruited as performing at world top 8 level in 2014, the most recent Winter Olympic Games. A semi structured interview protocol, using a personalized progress chart, enabled the examination of trick progression across disciplines, with at least one participant from each of the events represented at the Games. Trick progression was achieved intermittently, moving through different stages during the year subject to experiencing the right conditions, training facilities, balancing time for progression with time for consolidation, competition periods and rehabilitating from injuries. There was high variance in the duration of trick progression between individuals and also high variance in the number of repetitions required to land a trick in competition. Imagery was a mental skill widely used and universally supported by our sample. Athletes and coaches should take directionality into consideration when planning their progression, ensuring all four directions are included and that prerequisite manoeuvres are included in an athlete’s training repertoire at the right stage to facilitate the learning of more complex manoeuvres at a later stage of development. Our data found a 60–40 balance between time-spent training on and off-snow, further research is required to determine the best combination of traditional strength and conditioning versus movement conditioning approaches, both from an injury prevention and a performance enhancement perspective
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Convergent and divergent trajectories of corporate governance
This Special Issue revisits the classic question of comparative corporate governance research, namely whether national corporate governance systems are converging. More specifically, it focuses on several ‘convergence vectors’ which comprise the political, legal, economic and social arrangements that influence or drive the international trajectories of governance systems towards a common denominator. Taken together, the contributors to this Special Issue invite us to think critically about the functional explanations commonly mobilized in favour of convergence and consider instead the convergence debate from a broader and more interdisciplinary point of view
Introduction and Validation of the Juror Decision Scale (JDS): An Empirical Investigation of the Story Model
Purpose: To develop and validate a self-report measure of individual juror decision making within criminal trials, based on theoretical features set out in the Story Model of juror decision making. Methods: The Juror Decision Scale (JDS) and Acceptance of Modern Myths about Sexual Aggression (AMMSA) measure were completed by 324 jury-eligible participants split across 27 jury panels, after observing a rape trial re-enactment high in ecological validity. Dimensionality and construct validity of the JDS was investigated using traditional confirmatory factor analysis (CFA) techniques alongside confirmatory bifactor analysis at two time points (individual juror verdict decisions pre- and post-deliberation). Three competing models of the JDS were specified and tested using Mplus with maximum likelihood robust estimation. Results: Bifactor model with three meaningful factors (complainant believability, defendant believability, decision confidence) was the best fit for the data at both decision points. Good composite reliability and differential predictive validity were observed for the three JDS subscales. Conclusion: Alongside demonstrating its multidimensional conceptualisation, the JDS development permits future empirical testing of the Story Model theoretical assertions surrounding juror decision making. Present findings also provide early evidence of a certainty principle assessment process governing individual verdict decision formation. Theoretical and practical applications are discussed
What do we know about child abuse and neglect patterns of co-occurrence? A systematic review of profiling studies and recommendations for future research
Latent class (LCA) and latent profile (LPA) analysis represent methodological approaches to identify subgroups of maltreated individuals. Although research examining child abuse and neglect (CAN) profiles is still rare, the application of person-centered techniques to clarify CAN types co-occurrence has substantially increased in recent years. Therefore, the aim of the present study was to provide a summary and critical evaluation of the findings of LCA/LPA child maltreatment research to: (a) systemize the current understanding of patterns of maltreatment across populations and (b) elucidate interactive effects of CAN types on psychosocial functioning. A search in PsychInfo, Eric, PubMed, Scopus, and Science Direct, and Google Scholar was performed. Sixteen studies examining the co-occurrence between child physical abuse, emotional abuse, sexual abuse, neglect, and/or exposure to domestic violence were identified. A critical review of the studies revealed inconsistent findings as to the number of CAN classes, but most research uncovered a poly-victimized and a low abuse group. Further, multiple victimization was associated with most adverse internalizing and externalizing outcomes, especially when sexual abuse was present. Exposure to physical and emotional abuse was frequently reported to lead to behavioural problems. Based on the present study results, we provide a set of recommendations for surpassing the current methodological and conceptual limitations in future research
Use of tunable nanopore blockade rates to investigate colloidal dispersions
Tunable nanopores in elastomeric membranes have been used to study the
dependence of ionic current blockade rate on the concentration and
electrophoretic mobility of particles in aqueous suspensions. A range of
nanoparticle sizes, materials and surface functionalities has been tested.
Using pressure-driven flow through a pore, the blockade rate for 100 nm
carboxylated polystyrene particles was found to be linearly proportional to
both transmembrane pressure (controlled between 0 and 1.8 kPa) and particle
concentration (between 7 x 10^8 and 4.5 x 10^10 mL^-1). This result can be
accurately modelled using Nernst-Planck transport theory. Using only an applied
potential across a pore, the blockade rates for carboxylic acid and amine
coated 500 nm and 200 nm silica particles were found to correspond to changes
in their mobility as a function of the solution pH. Scanning electron
microscopy and confocal microscopy have been used to visualise changes in the
tunable nanopore geometry in three dimensions as a function of applied
mechanical strain. The pores observed were conical in shape, and changes in
pore size were consistent with ionic current measurements. A zone of inelastic
deformation adjacent to the pore has been identified as critical in the tuning
process
The performance of the EU-Rotate_N model in predicting the growth and nitrogen uptake of rotations of field vegetable crops in a Mediterranean environment
The EU-Rotate_N model was developed as a tool to estimate the growth and nitrogen (N) uptake of vegetable crop rotations across a wide range of European climatic conditions and to assess the economic and environmental consequences of alternative management strategies. The model has been evaluated under field conditions in Germany and Norway and under greenhouse conditions in China. The present work evaluated the model using Italian data to evaluate its performance in a warm and dry environment. Data were collected from four 2-year field rotations, which included lettuce (Lactuca sativa L.), fennel (Foeniculum vulgare Mill.), spinach (Spinacia oleracea L.), broccoli (Brassica oleracea L. var. italica Plenck) and white cabbage (B. oleracea convar. capitata var. alba L.); each rotation used three different rates of N fertilizer (average recommended N1, assumed farmer's practice N2=N1+0·3×N1 and a zero control N0). Although the model was not calibrated prior to running the simulations, results for above-ground dry matter biomass, crop residue biomass, crop N concentration and crop N uptake were promising. However, soil mineral N predictions to 0·6 m depth were poor. The main problem with the prediction of the test variables was the poor ability to capture N mineralization in some autumn periods and an inappropriate parameterization of fennel. In conclusion, the model performed well, giving results comparable with other bio-physical process simulation models, but for more complex crop rotations. The model has the potential for application in Mediterranean environments for field vegetable production
Can we use Hare’s psychopathy model within forensic and non-forensic populations? An empirical investigation
Although psychopathy construct (SRP-SF) was assessed among various samples, prior research did not investigate whether the model proposed by Hare and colleagues can be used to capture psychopathy scores derived from forensic and non-forensic populations. The main objective of the current study was to test dimensionality, construct validity, and factorial invariance of the SRP-SF within prison (N = 730) and student (N = 2,506) samples. Our results indicate that the SRP-SF measure cannot be used in the same way within forensic and non-forensic samples, which may be due to the inclusion of criminal/antisocial traits as an integral part of psychopathy
Energetics of linear geostrophic adjustment in stratified rotating fluids
The energy conversion ratio, γ, is shown to be bounded below by 0 and above by 1/2 in the two-dimensional linear geostrophic adjustment of a continuously stably stratified, incompressible, inviscid non-Boussinesq fluid. \u27\u27Two-dimensional\u27\u27 refers to problems in which the initial isopycnal displacement field is an arbitrary function of the vertical (parallel to the rotation axis) and a single horizontal coordinate. By using Fourier analysis techniques, the paper also identified classes of initial isopycnal displacement profiles for which the adjustment process leads to γ \u3e 1/3. Finally, an expression for γ is derived when the initial isopycnal displacement profile is three dimensional
Unit cell of graphene on Ru(0001): a 25 x 25 supercell with 1250 carbon atoms
The structure of a single layer of graphene on Ru(0001) has been studied
using surface x-ray diffraction. A surprising superstructure has been
determined, whereby 25 x 25 graphene unit cells lie on 23 x 23 unit cells of
Ru. Each supercell contains 2 x 2 crystallographically inequivalent subcells
caused by corrugation. Strong intensity oscillations in the superstructure rods
demonstrate that the Ru substrate is also significantly corrugated down to
several monolayers, and that the bonding between graphene and Ru is strong and
cannot be caused by van der Waals bonds. Charge transfer from the Ru substrate
to the graphene expands and weakens the C-C bonds, which helps accommodate the
in-plane tensile stress. The elucidation of this superstructure provides
important information in the potential application of graphene as a template
for nanocluster arrays.Comment: 9 pages, 3 figures, paper submitted to peer reviewed journa
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