257 research outputs found
Multidimensional Physical Self-Concept of Athletes With Physical Disabilities
The purposes of this investigation were first to predict reported PA (physical activity) behavior and self-esteem using a multidimensional physical self-concept model and second to describe perceptions of multidimensional physical self-concept (e.g., strength, endurance, sport competence) among athletes with physical disabilities. Athletes (N = 36, M age = 16.11, SD age = 2.8) completed the Physical Self- Description Questionnaire. Participants reported mostly positive perceptions of self-esteem, global physical self-concept, endurance, body fat, sport competence, strength, flexibility, and physical activity (Ms ranging from 3.9 to 5.6 out of 6). Correlations indicated a number of significant relationships among self-esteem and reported PA and various dimensions of physical self-concept. Using physical self-concept, strength, endurance, and flexibility in the first regression equation and sport competence and endurance simultaneously in the second equation, 47 and 31% of the variance was accounted for in self-esteem and reported PA, respectively. The findings support the value of examining multidimensional physical self-concept as different aspects of the physical self appear to have different influences on reported PA engagement versus self-esteem
Predictors of physical activity among European and American hearing impaired children
Research is scarce in relation to using social-cognitive theory inclusive of social-cognitive, affective and environmental constructs to predict physical activity (PA) and fitness with hearing impaired (HI) children. Hence, the purpose of our investigation was to evaluate the ability of social cognitive variables (e.g., self-efficacy and social support), environmental (i.e., time outside) and affective constructs (e.g., physical activity enjoyment) to predict PA. Children from the Czech Republic and the USA (N = 64, M age = 14.1) with hearing impairments completed questionnaires assessing predictor variables and PA. Using multiple regression analyses we accounted for 29% of the variance in PA. Based on standardized beta-weights, the best predictors of PA were gender, country, and a block of social-cognitive constructs. Compared to males and females from the Czech Republic and to females in the USA, American males receiving social support from their friends and who enjoyed physical education were the children most likely to be physically active. Future research examining environmental influences more fully (e.g., school settings, after school programs) both within the USA and cross-culturally and adult influences beyond parents (e.g., teachers, coaches) are encouraged
Infusing disability sport into the sport management curriculum
Disability sport is growing around the world with momentum and is described as a “movement” (Bailey, 2008; De- Pauw & Gavron, 2005). While there are more similarities than differences with sport management for able-bodied athletes and those with disabilities, there are additional needs and considerations for persons with disabilities (DePauw & Gavron, 2005). The noticeable visibility of individuals with disabilities in society, including sport, raises concerns about the degree to which sport management academic programs have modified their curricula to ensure that individuals working in the sport management field are prepared to deal with the uniqueness of disability sport. This paper (a) discusses theoretical perspectives toward understanding and thinking about disability, (b) explores ways to enhance sport management curricula through infusion of disability sport, (c) reflects upon current social practices for curriculum integration of athletes with disabilities in sport, and (d) acknowledges infusion of disability sport businesses, organizations and events
Motives for Sport Participation of Athletes with Intellectual Disability
The present study aimed at knowing the reasons which led Brazilian athletes with intellectual disability to engage in sports practice and to take part in competitions promoted by the Special Olympics Brazil. A hundred and two athletes, between 21 and 49 years old, were evaluated through the Sport Motivation Questionnaire developed by Shapiro (2003). The data showed that the athletes took part mainly to get ribbons and medals, to play with other people from the team, to go to new and different places and to feel like an important person. The order of importance given to the motives differs when the results are compared according to gender. It was noticed a significant difference between men and women and the group aged from 30 to 49 years considering the reason: to practice. The results of the present study reflect that the motives towards the sport practice of the athletes with intellectual disability are predominantly oriented by personal and environmental factors
Motives for Sport Participation of Athletes with Intellectual Disability
The present study aimed at knowing the reasons which led Brazilian athletes with intellectual disability to engage in sports practice and to take part in competitions promoted by the Special Olympics Brazil. A hundred and two athletes, between 21 and 49 years old, were evaluated through the Sport Motivation Questionnaire developed by Shapiro (2003). The data showed that the athletes took part mainly to get ribbons and medals, to play with other people from the team, to go to new and different places and to feel like an important person. The order of importance given to the motives differs when the results are compared according to gender. It was noticed a significant difference between men and women and the group aged from 30 to 49 years considering the reason: to practice. The results of the present study reflect that the motives towards the sport practice of the athletes with intellectual disability are predominantly oriented by personal and environmental factors
The Central Component of Gravitational Lens Q0957+561
In 1981, a faint radio source (G') was detected near the center of the
lensing galaxy of the famous "twin quasar" Q0957+561. It is still unknown
whether this central radio source is a third quasar image or an active nucleus
of the lensing galaxy, or a combination of both. In an attempt to resolve this
ambiguity, we observed Q0957+561 at radio wavelengths of 13cm, 18cm, and 21cm,
using the Very Long Baseline Array in combination with the phased Very Large
Array and the Green Bank Telescope. We measured the spectrum of G' for the
first time and found it to be significantly different from the spectra of the
two bright quasar images. This finding suggests that the central component is
primarily or entirely emission from the foreground lens galaxy, but the
spectrum is also consistent with the hypothesis of a central quasar image
suffering free-free absorption. In addition, we confirm the previously-reported
VLBI position of G' just north of the optical center of the lens galaxy. The
position slightly favors the hypothesis that G' originates in the lens, but is
not conclusive. We discuss the prospects for further clarification of this
issue.Comment: 18 pages, accepted for publication in A
Multi-Messenger Gravitational Wave Searches with Pulsar Timing Arrays: Application to 3C66B Using the NANOGrav 11-year Data Set
When galaxies merge, the supermassive black holes in their centers may form
binaries and, during the process of merger, emit low-frequency gravitational
radiation in the process. In this paper we consider the galaxy 3C66B, which was
used as the target of the first multi-messenger search for gravitational waves.
Due to the observed periodicities present in the photometric and astrometric
data of the source of the source, it has been theorized to contain a
supermassive black hole binary. Its apparent 1.05-year orbital period would
place the gravitational wave emission directly in the pulsar timing band. Since
the first pulsar timing array study of 3C66B, revised models of the source have
been published, and timing array sensitivities and techniques have improved
dramatically. With these advances, we further constrain the chirp mass of the
potential supermassive black hole binary in 3C66B to less than using data from the NANOGrav 11-year data set. This
upper limit provides a factor of 1.6 improvement over previous limits, and a
factor of 4.3 over the first search done. Nevertheless, the most recent orbital
model for the source is still consistent with our limit from pulsar timing
array data. In addition, we are able to quantify the improvement made by the
inclusion of source properties gleaned from electromagnetic data to `blind'
pulsar timing array searches. With these methods, it is apparent that it is not
necessary to obtain exact a priori knowledge of the period of a binary to gain
meaningful astrophysical inferences.Comment: 14 pages, 6 figures. Accepted by Ap
The effects of kisspeptin on β-cell function, serum metabolites and appetite in humans
Aims: To investigate the effect of kisspeptin on glucose-stimulated insulin secretion and appetite in humans. Materials and methods: In 15 healthy men (age: 25.2 ± 1.1 years; BMI: 22.3 ± 0.5 kg m−2), we compared the effects of 1 nmol kg−1 h−1 kisspeptin versus vehicle administration on glucose-stimulated insulin secretion, metabolites, gut hormones, appetite and food intake. In addition, we assessed the effect of kisspeptin on glucose-stimulated insulin secretion in vitro in human pancreatic islets and a human β-cell line (EndoC-βH1 cells). Results: Kisspeptin administration to healthy men enhanced insulin secretion following an intravenous glucose load, and modulated serum metabolites. In keeping with this, kisspeptin increased glucose-stimulated insulin secretion from human islets and a human pancreatic cell line in vitro. In addition, kisspeptin administration did not alter gut hormones, appetite or food intake in healthy men. Conclusions: Collectively, these data demonstrate for the first time a beneficial role for kisspeptin in insulin secretion in humans in vivo. This has important implications for our understanding of the links between reproduction and metabolism in humans, as well as for the ongoing translational development of kisspeptin-based therapies for reproductive and potentially metabolic conditions
Generalized Connective Tissue Disease in Crtap-/- Mouse
Mutations in CRTAP (coding for cartilage-associated protein), LEPRE1 (coding for prolyl 3-hydroxylase 1 [P3H1]) or PPIB (coding for Cyclophilin B [CYPB]) cause recessive forms of osteogenesis imperfecta and loss or decrease of type I collagen prolyl 3-hydroxylation. A comprehensive analysis of the phenotype of the Crtap-/- mice revealed multiple abnormalities of connective tissue, including in the lungs, kidneys, and skin, consistent with systemic dysregulation of collagen homeostasis within the extracellular matrix. Both Crtap-/- lung and kidney glomeruli showed increased cellular proliferation. Histologically, the lungs showed increased alveolar spacing, while the kidneys showed evidence of segmental glomerulosclerosis, with abnormal collagen deposition. The Crtap-/- skin had decreased mechanical integrity. In addition to the expected loss of proline 986 3-hydroxylation in α1(I) and α1(II) chains, there was also loss of 3Hyp at proline 986 in α2(V) chains. In contrast, at two of the known 3Hyp sites in α1(IV) chains from Crtap-/- kidneys there were normal levels of 3-hydroxylation. On a cellular level, loss of CRTAP in human OI fibroblasts led to a secondary loss of P3H1, and vice versa. These data suggest that both CRTAP and P3H1 are required to maintain a stable complex that 3-hydroxylates canonical proline sites within clade A (types I, II, and V) collagen chains. Loss of this activity leads to a multi-systemic connective tissue disease that affects bone, cartilage, lung, kidney, and skin
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