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81.
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
82.
Erin K. Howie Joanne A. McVeigh Rebecca A. Abbott Tim S. Olds Leon M. Straker 《Journal of sports sciences》2016,34(16):1581-1587
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
83.
AbstractMotorsport 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
84.
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
85.
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86.
87.
About 16,000 babies each year will be identified with hearing loss by age 3 months once universal newborn hearing screening becomes a reality. Identification of hearing loss in infancy, followed by appropriate intervention by age 6 months, can result in normal language development, regardless of degree of hearing loss. As the average age of identification of hearing loss moves downward toward 2 months, children with hearing loss will enter the educational system earlier and with language skills commensurate with those of their hearing peers. In order to provide appropriate services to children with hearing loss and their families, early interventionists will need to forge links to health care providers involved in universal newborn hearing screening programs, to have specialized training in deafness and hearing loss, and to have expertise in providing services to very young children and to children with hearing loss in the broad range from mild to profound. 相似文献
88.
Olson Joanne K. Cox-Petersen Anne M. McComas William F. 《Journal of Science Teacher Education》2001,12(3):155-173
Journal of Science Teacher Education - 相似文献
89.
K. C. Cheung 《Educational Studies in Mathematics》1989,20(1):97-103
This article seeks to examine gender differences across the mathematics curriculum in the various topic areas and mathematical abilities. It is suggested that a profile of these differences, when compared with students at different grade levels or across curricula, would be more fruitful for classroom teachers and curriculum developers. Breakdown and discriminant function statistics reveal that boys performed better than girls in Geometry and excelled in comprehension, and solving routine and non-routine problems. Girls were better at mathematical manipulation problems. 相似文献
90.
Rats were exposed twice in a rotated sequence to a series of six mazes, consisting of hexagonal alleys, balanced for different alley length and structural complexity. Locomotor activity increased with alley length and decreased with structural complexity of the mazes. Locomotion became less stereotyped with increased experience, showing an increasing number of turns, less constant velocity, loss of the initial preference for outward leading alleys and weakening of the forward tendency at reentry from side alleys into hexagonal alleys. In contrast to these qualitative changes of locomotion, the amount of activity remained almost unchanged throughout the experiment. The results suggest that these increases in locomotion complexity depend upon complex interactions between experience and stimulus content of the mazes. 相似文献