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This study assessed muscular torque and rate of torque development following concentric (CON) or eccentric (ECC) isokinetic training. Thirty-eight women were randomly assigned to either CON or ECC training groups. Training consisted of knee extension and flexion of the nondominant leg three times per week for 20 weeks (SD = 1). Eccentric training increased ECC knee extension and flexion peak torque more than CON training. The ECC group improved acceleration time and time to peak torque with ECC movements versus the CON group. Slow-velocity ECC isokinetic training yielded greater ECC and similar CON torque development gains versus CON training over the course of 20 weeks in young women.  相似文献   
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WISC-Rs and Stanford-Binets were administered to 50 children with developmental disabilities referred for comprehensive evaluations. Although the two IQs correlated highly and significantly, it was found that 54% of the children received different classifications using the two instruments. Thus, testers should be aware that different classifications of intellectual level may be derived for the same child depending upon which test is used.  相似文献   
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Abstract

Nine males and nine females were used as subjects to test the null hypothesis that there would be no significant differences between the performance of college age males and females on three motor tasks. Star tracing, tapping, and rotary pursuit were the tasks used under two conditions: (a) while looking at a mirror that would cause a reversal effect, and (b) under standard conditions without looking at a mirror. Results revealed no differences between males and females on the tasks performed without a mirror. However, the females performed significantly better on the same tasks while looking at a mirror.  相似文献   
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ABSTRACT

The length of telomeres is an objective measure of biologic ageing. This study evaluated the extent minutes of walking per week are associated with leukocyte telomere length (LTL) in a random sample of 5,823 U.S. adults. The investigation was cross-sectional and data were obtained from the National Health and Nutrition Examination Survey (NHANES). LTL was measured by the quantitative polymerase chain reaction method. Walking minutes was calculated from walking frequency and duration measures. Results showed that for each year of chronological age, telomeres were 15.6 base pairs shorter (P < 0.0001). With walking minutes and LTL treated as continuous variables, the relationship was quadratic, not linear (F = 11.2, P = 0.0023). With walking time divided into three categories, adults who performed ≥ 150 minutes of walking per week had longer telomeres than those who did no regular walking, and those who did some, but less than the recommendation (F = 5.0, P = 0.0137). Regular walkers were estimated to have a biologic ageing advantage associated with 6.5–7.6 years less biologic ageing compared to non-walkers, after adjusting for covariates. Additional investigations designed to study causality and the mechanisms associated with the walking and LTL relationship are needed.  相似文献   
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Are student attitudes toward science-technology-society (TSS) affected by visitation to science-technology museums? The purpose of this study was to determine whether such visitations affected student STS attitudes, and in what ways particular factors of the visitation impacted these attitudes. Factors examined included prior classroom experience with STS, instructional methodology employed by teachers, grade level, socioeconomic status, school type (public or private), and gender. The subjects involved in the study were 194 Kansas students in grades 6-8, and their 13 classroom teachers. Data were collected via a pretest-posttest control group design by using study-specific questionnaires and the Moore-Sutman Scientific Attitudes Inventory. Results indicated that significant differences in attitudes were present between visiting and nonvisiting students and between grade levels. No significant differences were found between other factors. One possible conclusion is that sound pedagogy should be used prior to and during museum visitations as well as in the classroom.  相似文献   
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We study the problem of web search result diversification in the case where intent based relevance scores are available. A diversified search result will hopefully satisfy the information need of user-L.s who may have different intents. In this context, we first analyze the properties of an intent-based metric, ERR-IA, to measure relevance and diversity altogether. We argue that this is a better metric than some previously proposed intent aware metrics and show that it has a better correlation with abandonment rate. We then propose an algorithm to rerank web search results based on optimizing an objective function corresponding to this metric and evaluate it on shopping related queries.  相似文献   
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This paper estimates models of the transitional effects of food insecurity experiences on children's non-cognitive performance in school classrooms using a panel of 4710 elementary students enrolled in 1st, 3rd, and 5th grade (1999-2003). In addition to an extensive set of child and household-level characteristics, we use information on U.S. counties to control for potential confounding effects of the local economic and noneconomic environment on children's household transitions between states of food insecurity and food security. The time horizon of our analysis affords insight into factors underlying children's formation of non-cognitive skills and the efficiency of classroom-based educational production in elementary school. Overall, we find significant negative developmental effects for children with food insecurity at home; and that children experiencing an early transition from food insecurity in 1st grade to food security in 3rd grade have even larger impairments that persist through 5th grade.  相似文献   
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