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131.
132.
Based on ideas from subjective uncertainty reduction theory, we examined the extent to which individuals hold similar sport team preferences to their family and friends. We also assessed the extent to which perceived sport importance and personal need for structure are influential in the development of team identification. Australian high school students aged 15.5+/-1.0 years (mean+/-s) completed questionnaires containing the Personal Need for Structure Scale, the Relational-Interdependent Self-Construal scale, a Team Identification Scale, and items assessing perceptions of sport importance and team preferences. As expected, correlations indicated that preferences for sport teams were significantly related to the preferences of family and friends. Separate analyses of variance confirmed the remaining hypotheses. More specifically, individuals who perceived that sport was important identified with the team more than individuals who perceived sport to be less important. Also, individuals high in personal need for structure scored higher in cognitive/affective team identification than those low in this need. Individuals with differing needs for structure did not differ in their scores on other dimensions of team identification. The results support the notion that cognitive/emotional attachments to sport teams are influenced by perceptions of the importance of sport and by needs for subjective structure. It is possible that other psychological motives, such as the desire for self-esteem, facilitate the development of evaluative dimensions of team identification. 相似文献
133.
The aim of this study was to examine the relationship between indicators of risk of disordered eating, body image and varied menstrual cycle lengths. Altogether, 151 female athletes were invited from 16 sports and 70 female non-athletic controls were recruited from a university lecture class. The participants completed several surveys, including demographics, menstrual cycle history, physical activity, Eating Disorder Inventory (EDI) and the Three Factor Eating Questionnaire (TFEQ). Selected EDI subscales were summed to reflect eating disorder risk and body image. Menstrual cyclicity was based on self-reported cycle length for the last 6 months (normal cycles = 26-32 days, irregular cycles < or =26 or >32 days). Athletes overall had more irregular cycles (29.1%) than the non-athletes (15.7%) (P < 0.05). There were significant differences in scores for eating disorder risk, body dissatisfaction, drive for thinness, cognitive restraint (TFEQ) and disinhibition (TFEQ), only when athletes were divided based on menstrual cyclicity (i.e. irregularly cycling athletes had higher scores than athletes with normal menstrual cycle lengths). No differences in these scores were found between non-athletes with normal or irregular menstrual cycle lengths. In conclusion, irregularly short or long menstrual cycle length is associated with subtle indications of higher risk of disordered eating in female athletes. 相似文献
134.
Females and youth are frequently described as "special" populations in football literature, but together these two populations outnumber male players. What makes females "special" is that they tend to eat less when training and competing than their male counterparts, leading to lower intakes of energy, carbohydrate, and some nutrients. Youth football players are special in regard to energy and nutrient requirements to promote growth and development, as well as to fuel sport. There is limited research on the dietary habits of these two populations, but the available literature suggests that many female and youth players need to increase carbohydrate intake, increase fluid intake, and develop dietary habits to sustain the demands of training and competition. 相似文献
135.
A.M. Morshedi 《Journal of The Franklin Institute》1980,310(2):89-105
Optimum process operating conditions are often achieved by on-line computer programming. A general method has been developed which is capable of optimizing processes whose responses are corrupted by random error. The method is particularly useful for application to processes whose response functions contain sharp ridges. Application to ridge and non-ridge systems gives the same results in each case showing that the rate of convergence of the search is totally unaffected by the presence of a ridge. An accelarated gradient method is used which obtains its derivatives from a quadratic interpolation. The inability of the gradient method to move along a ridge is overcome by projecting a straight line through points on the ridge to obtain new starting points for a gradient search. Points on the ridge are located by finding the stationary point of the polynomial which is constructed by regression through points found by the gradient search. The method is applied to several test functions known to the literature—a fast convergence rate is obtained for a wide range of noise levels. 相似文献
136.
J. Bruce Francis Michalina Vaughan Colin Flood Page Sally Tomlinson R. A. Becher Margaret C. Ives John Urry K. G. Collier Meir Zadok Charles Carter Jürgen Schramm Jean Barry Graeme C. Moodie Donald Bligh R. A. King D. G. Mulcahy Peter Scott F. R. Charmer T. R. Bone John A. Hughes Roger Greenhough Alec M. Ross John Wakeford Joyce Skinner Duncan B. Nimmo Cedric Cullingford L. R. B. Elton 《Higher Education》1979,8(6):709-744
137.
W.A Campbell 《Endeavour》1979,3(1):38-41
Chemical analysis is now so precise and sophisticated a science that it is difficult to appreciate that scarcely a century ago its deficiencies were a cause for public scandal. This article reviews some of the main causes for complaint and how they were remedied. 相似文献
138.
A sequence of tests on derived polynomials to be strictly Hurwitz polynomials is shown to be equivalent to a given (typically real) polynomial having all its zeros in an open sector, symmetric with respect to the real axis, in the left half-plane. The number of tests needed is at most 1 + ?(ln k)/(ln 3)?, where k is the integer associated with the central angle π/k of the sector. An extension of this result on the sector as a region of root clustering is given which shows that only a limited number of tests are needed to verify that the roots are clustered in a region composed as the intersection of a set of primative (sector-like) regions. The results reported evolve from application of a collection of mappings on the complex plane defined by a particular collection of Schwarz-Christoffel transformations. 相似文献
139.
140.
Dynamic retinoscopy has suggested that near vision may be more acute than far vision during early infancy. To test this, acuity thresholds were determined by presenting square wave gratings in a preference paradigm to 1- and 2-month-old human infants at 4 viewing distances. Gratings were paired with unpatterned fields; direction of first fixation was the dependent measure. Infants exhibited the same acuity at each of the distances at which gratings were presented. The results were interpreted as compatible with the fact that considerable optical defocusing does not seriously affect a visual system, such as the infant's, that is sensitive only to low spatial frequencies. 相似文献