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951.
Mark P. Moresi Elizabeth J. Bradshaw David A. Greene Geraldine A. Naughton 《Journal of sports sciences》2015,33(2):180-191
Double-leg repeated jumping tasks are commonly used as measures of lower limb stiffness in exercise science research. Within similar stiffness calculations, variation in data-reduction criteria exists. The impact of these varied data-reduction methods on stiffness measures is unknown. Sixteen adolescent female participants from varied physical activity backgrounds performed 15 self-paced, bent-knee continuous jumps (CJb) on two force plates. Leg stiffness was calculated as the ratio of the peak force and the centre of mass displacement for each contact. Using combinations of criteria based on previous literature, 83 data-reduction methods were applied to the raw data. Data reduction suitability was assessed based on intra-trial reliability, the number of participants excluded and the average contacts excluded. Four data-reduction methods were deemed suitable for use with adolescent female populations, with three consecutive contacts within 1 SD of the average jump frequency considered optimal. The average individual stiffness values were not greatly influenced by the data-reduction method; however, for a single participant, a stiffness change of up to 6 kN · m?1 (30%) was observed. The role and potential impact of data-reduction methods used to evaluate measures of lower limb stiffness during repeated jumping tasks warrants consideration. 相似文献
952.
953.
Songliang Wang Claude Caldwell Liqing Wei Haiyan Su 《Frontiers of Education in China》2015,10(3):427-438
The Fujian Agriculture and Forestry University-Nova Scotia Agricultural College (FAFU-NSAC) 2 + 2 undergraduate program initiated in 2003 is a model for creative collaboration between China and Canada in undergraduate education. This paper addresses the achievements of the program development and highlights the process for successful curriculum development in the joint program. The authors also discuss some issues and challenges related to the Chinese-Canadian experience in undergraduate education, and propose some recommendations for further collaborations including: enlarging the scale of qualified programs; proposing a systematic baseline to control the program at a macro-level; simplifying coordination procedures with foreign partners; and adjusting the emphasis of courses introduced by the cooperative partner from quantity to quality. 相似文献
954.
This study investigates 1.5 generation1 Asian immigrant children’s (n = 264) early literacy achievement patterns, treating them as a heterogeneous group. Specifically, the within-group variances in reading achievement from kindergarten to third grade are examined, drawing on four waves of data from the ECLS-K class of 1998–1999. Our analysis shows that ethnicity plays a role in shaping the children’s initial reading readiness and later growth, but the effects of languages spoken at home are not significant. Our analysis also demonstrates a persistent achievement gap between low- and high-socioeconomic status (SES) Asian groups. However, gender difference in terms of children’s reading development is not found to be significant. There is also no interaction between SES and the other factors such as gender, ethnicity and language backgrounds. 相似文献
955.
956.
957.
The development of ovarian follicular cells is controlled by multiple circulating and local hormones and factors, including
follicle-stimulating hormone (FSH) and epidermal growth factor (EGF). In this study, the stage-specific effect of EGF on FSH-induced
proliferation of granulosa cells was evaluated in the ovarian follicles of egg-laying chickens. Results showed that EGF and its receptor (EGFR) mRNAs displayed a high expression in granulosa cells from the prehierarchical follicles, including the large white follicle
(LWF) and small yellow follicle (SYF), and thereafter the expression decreased markedly to the stage of the largest preovulatory
follicle. SYF represents a turning point of EGF/EGFR mRNA expression during follicle selection. Subsequently the granulosa cells from SYF were cultured to reveal the mediation
of EGF in FSH action. Cell proliferation was remarkably increased by treatment with either EGF or FSH (0.1–100 ng/ml). This
result was confirmed by elevated proliferating cell nuclear antigen (PCNA) expression and decreased cell apoptosis. Furthermore,
EGF-induced cell proliferation was accompanied by increased mRNA expressions of EGFR, FSH receptor, and the cell cycle-regulating
genes (cyclins D1 and E1, cyclin-dependent kinases 2 and 6) as well as decreased expression of luteinizing hormone receptor
mRNA. However, the EGF or FSH-elicited effect was reversed by simultaneous treatment with an EGFR inhibitor AG1478. In conclusion,
EGF and EGFR expressions manifested stage-specific changes during follicular development and EGF mediated FSH-induced cell
proliferation and retarded cell differentiation in the prehierarchical follicles. These expressions thus stimulated follicular
growth before selection in the egg-laying chicken. 相似文献
958.
Gas-liquid coupling oscillation is a novel approach to reducing the resonant frequency and to elevating the pressure amplitude
of a thermoacoustic engine. If a thermoacoustic engine is used to drive low-frequency pulse tube refrigerators, the frequency
matching between the thermoacoustic engine and the refrigerator plays an important role. Based on an acoustic-electric analogy,
a lumped parameter model is proposed to estimate the resonant frequency of a standing-wave thermoacoustic engine with gas-liquid
coupling oscillation. Furthermore, a simplified lumped parameter model is also developed to reduce the computation complexity.
The resonant frequency dependence on the mean pressure, the gas space volume, and the water column length is computed and
analyzed. The impact of different working gases on the resonant frequency is also discussed. The effectiveness of the models
is validated by comparing the computed results with the experimental data of the gas-liquid coupling oscillation system. An
increase in the mean working pressure can lead to a rise in the resonant frequency, and a lower resonant frequency can be
achieved by elongating the liquid column. In comparison with nitrogen and argon, carbon dioxide can realize a lower frequency
due to a smaller specific heat ratio. 相似文献
959.
There are movements internationally towards curricula that incorporate values and citizenship education. In Australia, this movement has been illustrated with the adoption of a national curriculum in values education. This has arisen from the perceived need for citizens to hold values around the rights and responsibilities of functioning within a democracy. The Making News Today programme has been designed to develop a range of literacies enabling learners, for example, to read the media beyond the interests of the elite. The programme incorporates a journalistic process for television news production for middle school students using laptop and handheld video technologies, with embedded ethics and values education. The article reports on an analysis of the implementation of this programme with middle school students in Australia with reference to student adoption of ethical stances in the journalistic process and the implications for the use of this project in developing ethics, values and citizenship as part of the curriculum process. 相似文献
960.
如果说正义是人类道德交往的基本法则或者维度,那么这也似乎适用于一些教育问题。简而言之,我们需要教育孩子和年轻人正义和公平。然而,这并不是可以仅通过教授正义的理论就能够实现的。因为,正如这篇文章所揭示的那样,这些理论通常涉及到维护正义的准则,即在有些情况下,公民个体不能总是做到如其所期待的那样正义与公平。所以,正义教育更多的是培养正义的美德。从这点出发,本文致力于探究如何借助富有想象力的文学作品来培养正义的美德。 相似文献