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K. R. Shivanna 《Resonance》2016,21(11):1007-1018
After the pollen grain reaches the stigma through outsourced agents (pollinators), the next step before fertilization is to select the right type of pollen. Similar to a marriage in human beings, fiowering plants also have evolved elaborate screening process to select the right pollen grains and to reject the wrong ones. Even after initial screening for the right pollen, the pistil imposes a tough competition amongst them, comparable to a swayamvara of Indian mythology, to select the best available pollen. Flowering plants have evolved into a matriarchal society. The selection of the male partner is totally the prerogative of the mother (pistil); the boy (pollen grain) and the girl (ovule) has no say in this selection.  相似文献   
114.
Fitness is an important component of health, and obese adolescents regularly have poor fitness. Unfortunately, few have assessed the impact of community-based lifestyle interventions on multiple components of fitness. The purpose of this study was to assess the impact of participation in a community-based intervention involving adolescents and parents on multiple components of fitness of obese adolescents. In a within-subject, waitlist controlled clinical trial with 12 months follow-up in Western Australia, participants (n = 56) completed multiple fitness measures at baseline, immediately prior to beginning an 8-week intervention and at 3, 6 and 12 months during a maintenance period. Performance on the shuttle walk was improved immediately post-intervention (increase of 42.8 m, 95% CI: 7.5, 78.2) and at 12 months post-intervention (increase of 44.6 m, 95% CI: 1.3, 87.8) compared with pre-intervention. Muscle performance of quadriceps and deltoids were improved post-intervention (increase of 1.1 (95% CI: 0.1, 2.1) kg · F and 1.0 (0.02, 2.1) kg · F, respectively) and all muscle performance measures were improved at 12 months following the intervention. There were no changes in waist circumference. A community-based lifestyle programme such as Curtin University’s Activity, Food and Attitudes Program (CAFAP) may be a viable strategy for improving fitness in overweight adolescents.  相似文献   
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Abstract

The persistence of white privilege and escalating racism in the United States challenges religious educators to analyze the roots and destructive potential of both. This article draws on historical and contemporary analyses in dialogue with personal reflection and the oral histories of two leaders who seek to recognize and live beyond their own privilege. The purpose of the study is to describe the landscape of white privilege and analyze the intersections of public and personal dynamics. The analysis reveals the educational potential of personal narratives and structural analysis in understanding and transforming white privilege into humble work for justice.  相似文献   
116.
Motor performance is an important health resource. Review articles revealed a decline of motor performance of approximately 10?% between 1975 and 2006. In the past most of the data available for such comparisons came from ad hoc studies with non-standardized methods. Within the framework of the ”Motorik-Modul“ (MoMo) study as part of the German Health Interview and Examination Survey for Children and Adolescents (KiGGS), it is possible for the first time to directly compare two cohorts in the ages of 4–17 years in a nationally representative database for Germany. The aim of this article is to report changes in motor performance of children and adolescents in the time period 2003–2006 (cohort baseline n = 4528) compared to 2009–2012 (cohort wave 1, n = 2820). Overall, it is clearly shown that the motor performance of children and adolescents in Germany did not decrease within the observational period of 6 years. The comparison of mean values of the baseline cohort compared to those of wave 1 showed that 28 out of 52 mean values of the two cohorts with a high probability did not differ based on 95?% confidence intervals (CI). In 24 out of the 52 mean values positive changes could be noted based on the individual 95?% CI values. There were more positive changes in primary school aged children than in other age groups. Within these positive changes, most effect sizes were small to medium. The results indicate that recent activities aiming at elevating motor performance levels may have started to make an impact and should be expanded, also in secondary schools. The comparative cohort study presented in this article is currently being checked by the ongoing MoMo wave 2 survey of 2014–2017.  相似文献   
117.
Abstract

Motorsport is an under-researched area of socio-historical study. There is particularly limited academic understanding of female involvement in the social world of motorsports. Therefore, this paper focuses on the role of the media in presenting and establishing motorsport for women. In particular, a documentary analysis of articles published by a UK national newspaper group from 1890, and a case study of an all-female UK-based motor-racing championship are used to account for gendered processes that have influenced attitudes and behaviours towards women motor racers. The motor car emerged through technological progress in an overtly masculine-dominated industrial period. Traditional assumptions and biologically deterministic attitudes towards women were used by men to position motoring and motor-racing as a male preserve. Newspaper reporting throughout the 1930s suggests an era of heightened success for women motor racers as a result of gaining access to a key resource in the form of Brooklands motor-racing circuit. Following the Second World War, there was increasing commercialization and professionalization of male-dominated motorsport, as well as renewed marginalization and trivialization of female participants within the newspapers. These processes continue to influence perceptions of women in contemporary motorsport.  相似文献   
118.
In this article, the authors borrow from anti-oppressive education theory for its potential to disrupt how students visually conceive sporting bodies and to problematize the teaching and learning of these bodies within undergraduate physical education (PE) programs. Fourteen photo stories produced by students enrolled in PE programs at two universities were analysed using a semiotic approach to excavate the emergent themes of sporting bodies from the narratives. Relying on Kumashiro's anti-oppressive educational theoretical framework, the authors found that most of stories reified discursive practices that (re)produce gender oppression in sport. Despite these findings, the authors also discovered anti-oppressive pedagogies are useful for teaching against the body oppressions conveyed in the photo stories. How anti-oppressive education informs other areas of PE should be examined in the future.  相似文献   
119.
The present study examined the sex-specific associations of moderate and vigorous physical activity (VPA) with physical fitness in 300 Japanese adolescents aged 12–14 years. Participants were asked to wear an accelerometer to evaluate physical activity (PA) levels of various intensities (i.e. moderate PA (MPA), 3–5.9 metabolic equivalents (METs); VPA, ≥6 METs; moderate to vigorous PA (MVPA), ≥3 METs). Eight fitness items were assessed (grip strength, bent-leg sit-up, sit-and-reach, side step, 50?m sprint, standing long jump, handball throw, and distance running) as part of the Japanese standardised fitness test. A fitness composite score was calculated using Japanese fitness norms, and participants were categorised according to their score from category A (most fit) to category E (least fit), with participants in categories D and E defined as having low fitness. It was found that for boys, accumulating more than 80.7?min/day of MVPA may reduce the probability of low fitness (odds ratio (ORs) [95% confidence interval (CI)]?=?0.17 [0.06–0.47], p?=?.001). For girls, accumulating only 8.4?min of VPA could reduce the likelihood of exhibiting low fitness (ORs [95% CI]?=?0.23 [0.05–0.89], p?=?.032). These results reveal that there are sex-specific differences in the relationship between PA and physical fitness in adolescents, suggesting that sex-specific PA recommendation may be needed to improve physical fitness in adolescents.  相似文献   
120.

Objective

The purpose of this study was to investigate the relative effectiveness of three web-scale discovery (WSD) tools in answering health sciences search queries.

Methods

Simple keyword searches, based on topics from six health sciences disciplines, were run at multiple real-world implementations of EBSCO Discovery Service (EDS), Ex Libris''s Primo, and ProQuest''s Summon. Each WSD tool was evaluated in its ability to retrieve relevant results and in its coverage of MEDLINE content.

Results

All WSD tools returned between 50%–60% relevant results. Primo returned a higher number of duplicate results than the other 2 WSD products. Summon results were more relevant when search terms were automatically mapped to controlled vocabulary. EDS indexed the largest number of MEDLINE citations, followed closely by Summon. Additionally, keyword searches in all 3 WSD tools retrieved relevant material that was not found with precision (Medical Subject Headings) searches in MEDLINE.

Conclusions

None of the 3 WSD products studied was overwhelmingly more effective in returning relevant results. While difficult to place the figure of 50%–60% relevance in context, it implies a strong likelihood that the average user would be able to find satisfactory sources on the first page of search results using a rudimentary keyword search. The discovery of additional relevant material beyond that retrieved from MEDLINE indicates WSD tools'' value as a supplement to traditional resources for health sciences researchers.  相似文献   
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