Developmental Trends in Sexual Attraction Among Puerto Rican Early Adolescents in Two Contexts

Sexual attraction (SA), the earliest stage of sexual orientation, is scarcely studied. This prospective study examined, over 3 years, prevalence, changes in SA, and the role of context, among 946 Puerto Rican youth, aged 11–13 years at initial assessment in the South Bronx (SBx), New York City, and Puerto Rico (PR). Overall, 98.1% of boys and 95.3% of girls reported opposite-sex only SA at some point, whereas 13.8% of girls and 12.0% of boys reported any-same SA. Opposite-sex only SA increased over time, whereas other SAs decreased except for any same-sex SA among SBx girls. Girls in the SBx and younger youth in PR reported more any same-sex SA. Context and culture may play a role in the developmental trajectories of adolescents’ SA.     

International Trends in Health Science Librarianship Part 20: The Balkan States (Serbia and Slovenia)

This is the 20th in a series of articles exploring international trends in health science librarianship in the 21st century. The focus of the present issue is the Balkan region (Serbia and Slovenia). The next regular feature will look at Russia and the Ukraine. JM     

Effects of replica running shoes upon external forces and muscle activity during running

Twelve participants ran (9 km · h(-1)) to test two types of running shoes: replica and original shoes. Ground reaction force, plantar pressure and electromyographic activity were recorded. The shoes were tested randomly and on different days. Comparisons between the two experimental conditions were made by analysis of variance (ANOVA) test (P ≤ 0.05). The time to first peak, loading rate of the first peak and impulse of the first 75 ms of stance were significantly different between the shoes (P ≤ 0.05), revealing an increase of impact forces for the replica shoes. The peak plantar pressure values were significantly higher (P ≤ 0.05) when wearing replica shoes. During running, the contact area was significantly smaller (P ≤ 0.05) for the replica shoe. The electromyographic activity of the analysed muscles did not show changes between the two shoes in running. These findings suggest that the use of replica running shoes can increase the external load applied to the human body, but may not change the muscle activity pattern during locomotion. This new mechanical situation may increase the risk of injuries in these movements.     

Differences between the sexes in technical mastery of rhythmic gymnastics

The aims of this study were to determine possible differences between the sexes in specific rhythmic gymnastics techniques, and to examine the influence of various aspects of technique on rhythmic composition performance. Seventy-five students aged 21?±?2 years (45 males, 30 female) undertook four test sessions to determine: coefficients of asymmetry, stability, versatility, and the two rhythmic compositions (without apparatus and with rope). An independent-sample t-test revealed sex-based differences in technique acquisition: stability for ball (P?相似文献   

The association of major patterns of physical activity,sedentary behavior and sleeping with mortality in older adults

Objective: To identify major patterns of physical activity (PA), sedentary behavior (SB) and sleeping (all self-reported), and their association with long-term mortality.

Methods: Cohort of 2,851 individuals aged ≥ 60 from Spain. Mortality was ascertain from 2003 up to July 2013. Patterns of PA, SB and sleeping were identified by factor analysis.

Results: During follow-up, 1,145 deaths occurred. The first pattern, named “sedentary and non-active pattern”, was characterized by long sleeping or lying time, and not doing even light PA (household chores or walking). The second pattern was named “active and non-sedentary pattern”, and was characterized long time devoted to vigorous activities, long walking time, and short seating time. Compared to those in the first quartile of the “sedentary and non-active pattern”, those in the highest quartile showed a 71% higher mortality (HR: 1.71; 95%CI: 1.42–2.07; p-trend:<0.001); it corresponds to being 6-year older. By contrast, being in the highest versus the lowest quartile of the “active and non-sedentary pattern” was associated with a 32% lower mortality (HR: 0.68: 0.57–0.82; p-trend:<0.001); it corresponds to being 4-year younger.

Conclusion: The “sedentary and non-active” pattern had a large impact on mortality. The “active and non-sedentary” pattern showed an opposite and slightly lower association.