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Quasi-diffusion magnetic resonance imaging (QDI): A fast, high b-value diffusion imaging technique.
To enable application of non-Gaussian diffusion magnetic resonance imaging (dMRI) techniques in large-scale clinical trials and facilitate translation to clinical practice there is a requirement for fast, high contrast, techniques that are sensitive to changes in tissue structure which provide diagnostic signatures at the early stages of disease. Here we describe a new way to compress the acquisition of multi-shell b-value diffusion data, Quasi-Diffusion MRI (QDI), which provides a probe of subvoxel tissue complexity using short acquisition times (1-4 min). We also describe a coherent framework for multi-directional diffusion gradient acquisition and data processing that allows computation of rotationally invariant quasi-diffusion tensor imaging (QDTI) maps. QDI is a quantitative technique that is based on a special case of the Continuous Time Random Walk model of diffusion dynamics and assumes the presence of non-Gaussian diffusion properties within tissue microstructure. QDI parameterises the diffusion signal attenuation according to the rate of decay (i.e. diffusion coefficient, D in mm2 s-1) and the shape of the power law tail (i.e. the fractional exponent, α). QDI provides analogous tissue contrast to Diffusional Kurtosis Imaging (DKI) by calculation of normalised entropy of the parameterised diffusion signal decay curve, Hn, but does so without the limitations of a maximum b-value. We show that QDI generates images with superior tissue contrast to conventional diffusion imaging within clinically acceptable acquisition times of between 84 and 228 s. We show that QDI provides clinically meaningful images in cerebral small vessel disease and brain tumour case studies. Our initial findings suggest that QDI may be added to routine conventional dMRI acquisitions allowing simple application in clinical trials and translation to the clinical arena
A mediation meta-analysis of the role of maternal responsivity in the association between socioeconomic risk and children's language
This meta-analysis tested maternal responsivity as a mediator of the association between socioeconomic risk and children's preschool language abilities. The search included studies up to 2017 and meta-analytic structural equation modeling, allowed us to examine the magnitude of the indirect effect across 17 studies (k = 19). The meta-analysis included 6433 predominantly White, English speaking children (Mage = 36 months; 50% female) from Western, industrialized countries. All paths in the model were statistically significant, notably, the indirect effect was significant (b = -.052), showing that maternal responsivity may be a proximal intervening variable between socioeconomic risk and children's language development. Moderator analyses found that the indirect effect was stronger for sensitive parenting than warmth and when parenting was assessed in the family home
Perfectionism and training distress in junior athletes: A longitudinal investigation
Perfectionistic athletes may train harder and for longer than non-perfectionistic athletes, leaving them susceptible to elevated levels of training distress. So far, however, no study has investigated the relationships between perfectionism and training distress, a key indicator of overtraining syndrome. Furthermore, no study has determined psychological predictors of overtraining syndrome. Using a two-wave design, the present study examined perfectionistic strivings, perfectionistic concerns, and training distress in 141 junior athletes (mean age 17.3 years, range 16-19 years) over 3 months of active training. Multiple regression analyses were employed to test cross-sectional and longitudinal relationships between perfectionism and training distress. In all analyses, perfectionism emerged as a significant predictor, but strivings and concerns showed differential relationships. When the cross-sectional relationships were regarded, perfectionistic concerns positively predicted training distress (p .05). The findings suggest that sports scientists who wish to identify athletes at risk of overtraining syndrome may monitor athletes’ perfectionistic concerns as a possible risk factor
The prevalence of pseudoscientific ideas and neuromyths among sports coaches
There has been an exponential growth in research examining the neurological basis of human cognition and learning. Little is known, however, about the extent to which sports coaches are aware of these advances. Consequently, the aim of the present study was to examine the prevalence of pseudoscientific ideas among British and Irish sports coaches. In total, 545 coaches from the United Kingdom and Ireland completed a measure that included questions about how evidence-based theories of the brain might enhance coaching and learning, how they were exposed to these different theories, and their awareness of neuromyths. Results revealed that the coaches believed that an enhanced understanding of the brain helped with their planning and delivery of sports sessions. Goal-setting was the most frequently used strategy. Interestingly, 41.6% of the coaches agreed with statements that promoted neuromyths. The most prevalent neuromyth was “individuals learn better when they receive information in their preferred learning style (e.g., auditory, visual, or kinesthetic)”, which 62% of coaches believed. It is apparent that a relatively large percentage of coaches base aspects of their coaching practice on neuromyths and other pseudoscientific ideas. Strategies for addressing this situation are briefly discussed and include changing the content of coach education progra
A short review of perfectionism in sport, dance and exercise: Out with the old, in with the 2 × 2.
The purpose of the current paper is to review research examining multidimensional perfectionism in sport, dance, and exercise. We start by providing a conceptual overview of perfectionism. We then describe three main approaches to examining perfectionism. These approaches are an independent effects approach, the tripartite model, and the 2 × 2 model of perfectionism. Alongside the description of each approach, research findings are summarized. We close the paper by explaining how the development of the 2 × 2 model has likely rendered the tripartite model obsolete
Perfectionism, mattering, stress, and self-regulation of home learning of UK gifted and talented students during the COVID-19 pandemic
The COVID-19 pandemic forced the closure of schools in the UK and students had to study at home with limited access to the support they would have normally received. We designed this study to assess the experience of gifted and talented (GAT) students during this period and to identify factors related to their stress and self-regulation of learning. The factors we focused on were perfectionism and feelings of mattering. Three-hundred and eleven GAT students completed an online questionnaire when schools were closed and they were studying at home. Analyses revealed that striving for perfection was related to better effort regulation and better time and environment management. However, negative reactions to imperfection and feeling like they did not matter (anti-mattering) were related to higher academic stress, as well as worse effort regulation and worse time and environment management. The findings suggest aspects of both perfectionism and mattering may be important for GAT students’ ability to study effectively during the COVID-19 pandemic
Exploring and evaluating the two-factor model of perfectionism in sport
Perfectionism is a multidimensional personality trait with two higher-order dimensions; perfectionistic strivings and perfectionistic concerns. The purpose of the present study was to explore and evaluate the two-factor model for the first time using three instruments developed to measure perfectionism in sport. In doing so, we (i) assessed the fit of two-factor models when including and excluding various contentious subscales (other-oriented perfectionism, parental pressure, coach pressure, organisation, and negative reactions to imperfection) and (ii) compared two-factor models to alternative one-factor (or unidimensional) models. Participants were recruited from community and university sports clubs in the UK (N = 527; M age = 18.07 years, SD = 0.49) and completed the Sport-Multidimensional Perfectionism Scale-2, the Multidimensional Inventory of Perfectionism in Sport, and the Performance Perfectionism Scale-Sport. Support was found for the two-factor model, with superior fit displayed each time the aforementioned subscales were excluded and, in all cases, when compared to a unidimensional model. The findings suggest that the two-factor model is an adequate representation of the underlying structure of instruments designed to measure perfectionism in sport with better fit and conceptual clarity offered by more parsimonious models
LArPix: Demonstration of low-power 3D pixelated charge readout for liquid argon time projection chambers
We report the demonstration of a low-power pixelated readout system designed
for three-dimensional ionization charge detection and digital readout of liquid
argon time projection chambers (LArTPCs). Unambiguous 3D charge readout was
achieved using a custom-designed system-on-a-chip ASIC (LArPix) to uniquely
instrument each pad in a pixelated array of charge-collection pads. The LArPix
ASIC, manufactured in 180 nm bulk CMOS, provides 32 channels of
charge-sensitive amplification with self-triggered digitization and multiplexed
readout at temperatures from 80 K to 300 K. Using an 832-channel LArPix-based
readout system with 3 mm spacing between pads, we demonstrated low-noise
(500 e RMS equivalent noise charge) and very low-power (100
W/channel) ionization signal detection and readout. The readout was used
to successfully measure the three-dimensional ionization distributions of
cosmic rays passing through a LArTPC, free from the ambiguities of existing
projective techniques. The system design relies on standard printed circuit
board manufacturing techniques, enabling scalable and low-cost production of
large-area readout systems using common commercial facilities. This
demonstration overcomes a critical technical obstacle for operation of LArTPCs
in high-occupancy environments, such as the near detector site of the Deep
Underground Neutrino Experiment (DUNE).Comment: 19 pages, 10 figures, 1 ancillary animation. V3 includes minor
revisions based on referee comment
A longitudinal study of perfectionism and orthorexia in exercisers
Research suggests that trait perfectionism and perfectionistic self-presentation are related to orthorexia – a pathological obsession with correct nutrition. However, no studies have examined these relationships over time or compared the influence of the two aspects of perfectionism on orthorexia. In the present study we sought to address these two issues. Gym members who engaged in high degrees of exercise were recruited via social media platforms. They completed an online questionnaire that included the Multidimensional Perfectionism Scale-Short Form, Perfectionistic Self-Presentation Scale, and the Eating Habits Questionnaire on two occasions: 177 participants (Mean age = 31.6 years) initially completed the questionnaire and 82 completed the questionnaire six weeks later. A series of multiple regression analyses revealed that (i) trait perfectionism predicted an increase in orthorexia symptomatology over time with socially prescribed perfectionism and other-oriented perfectionism unique predictors of orthorexia, (ii) perfectionistic self-presentation predicted orthorexia over time with nondisplay of imperfection a unique predictor of orthorexia, and (iii) when considered alongside each other, only trait dimensions of perfectionism were unique predictors of orthorexia. The present study provides further evidence that perfectionism is related to orthorexia. In addition, the study also provides preliminary evidence that more engrained trait aspects of perfectionism are more predictive of intensifying orthorexia over time than the self-presentational aspects of perfectionism
Perfectionism and pre-competition emotions in youth footballers: a three-wave longitudinal test of the mediating role of perfectionistic cognitions
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