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971.
972.
The aim of this study was to identify differences between elite male and female pole vaulters in terms of their mechanical energy and angular momentum. The vaulter's total mechanical energy and angular momentum were calculated from the three-dimensional kinematic data of the pole vault finals at the Sydney 2000 Olympic Games. The development of total, kinetic and potential energy showed similar characteristics for men and women. The initial energy of the vault, the energy at maximum pole bend position and the final energy were significantly higher for male athletes (P <0.05), while the energy gain produced by the athletes during the vault showed no significant differences (male vaulters 5.88 +/- 1.02 J.kg(-1), female vaulters 5.74 +/- 1.63 J.kg(-1)). Time-related parameters relating to pole bending and recoiling also showed no significant differences (P <0.05). In contrast to the male vaulters, the female vaulters did not show a free upward flight phase. The angular momentum was significantly higher for the female vaulters during the initial pole bend and during the bar clearance (P <0.05). We conclude that the pole vaulting technique of female elite athletes is not a projection of the technique of male elite vaulters at a lower jump height, but rather a different way of jumping and interacting with the elastic pole. The current technique of elite female pole vaulters still has potential for further improvement.  相似文献   
973.
Data for this study were from a population survey of 1,200 adults ages 40-60 years, sampled from the Illawarra region of New South Wales. Questionnaire items on perceptions of the environment were factor analyzed into: Aesthetic Environment and Practical Environment. For both factors, those in the Contemplation stage had more negative views of the environment than those in Maintenance. Those who walked for 0-20 min/week held more negative perceptions of their environment than those who walked for 21-120 min/week and those who walked for > 120 min/week. The health promotion implications of these findings are that environments perceived as attractive and as providing convenient access to services and facilities may influence motivational readiness for physical activity and time spent walking.  相似文献   
974.
V Rajaraman 《Resonance》2000,5(11):26-36
In this part we will depict the infrastructure required for ecommerce as a six layered architecture and describe the three bottom layers.  相似文献   
975.
Editorial     
  相似文献   
976.
977.
Stress and women     
Stress-tension-pain occur more often in health disorders of women than anywhere in the entire spectrum of human illness. No where is the effect of rapid change more apparent than in the changing role of today's women who are subjected to pressures from all sides. Now a days women virtually take part occupy positions, in day to day activities similar to their male counterparts. An outline of conceptual consideration, biochemical overview of stress and intricacies of coping mechanisms are delineated from the point of view of stress situations in female (during reproductive life span) peculiar to them only viz menarche, menstrual cycle, pregnancy-eventualities of pregnancy-labour-delivery, purperium, postpartum psychosis, abortions-induced, spontaneous, menopause. Lipid profile and oxidative stress status as biochemical responses in these stresses were investigated. As expected observed maximal/minimal biochemical responses well correlated with peak time and at termination of stress. Present day emphasis is on menstrual regulation by intake of oral contraceptive to improve health if women prefer not to bleed every month and hormone replacement therapy for elderly women to improve post menopausal quality of life and avoiding menstrual problems at the same time.  相似文献   
978.
Postsecondary schools have traditionally relied on admissions tests such as the SAT and ACT to select students. With high school achievement assessments in place in many states, it is important to ascertain whether scores from those exams can either supplement or supplant conventional admissions tests. In this study we examined whether the Arizona Instrument to Measure Standards (AIMS) high school tests could serve as a useful predictor of college performance. Stepwise regression analyses with a predetermined order of variable entry revealed that AIMS generally did not account for additional performance variation when added to high school grade-point average (HSGPA) and SAT. However, in a cohort of students that took the test for graduation purposes, AIMS did account for about the same proportion of variance as SAT when added to a model that included HSGPA. The predictive value of both SAT and AIMS was generally the same for Caucasian, Hispanic, and Asian American students. The ramifications of universities using high school achievement exams as predictors of college success, in addition to or in lieu of traditional measures, are discussed.  相似文献   
979.
980.
This paper presents an ontological approach to generating automated medical technological records (MTRs). The medical organizational TR meta-ontology has been developed based on the paper variant of 63 technological records that are used at the Medical Center of the Bank of Russia. The paper describes the key elements of an automated MTR. The MTR ontology for bronchial asthma attack is used as an example.  相似文献   
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