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Institutional and student level data from the Florida Community Colleges were examined to explore the Retention Index of the Community College Survey of Student Engagement (CCSSE). A simple correlation and regression analysis was conducted to determine if the CCSSE Retention Index could be used to predict the institutional retention rate calculated for the state accountability measure. Student level data were used with a nested ANOVA to examine if there were mean differences in the CCSSE Retention Index scores of males and females of different racial groups when accounting for the potential influence of the institution attended. Mean differences were examined since differences in retention rates of these groups have been documented.  相似文献   
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The goal of this work is to better understand the institutional changes in the educational systems of the Czech Republic, Hungary, Poland and Slovakia. We demonstrate that the educational reforms implemented during the transformation introduced very different institutional arrangements in the four countries, despite the fact that their systems shared many common characteristics at the beginning of the 1990s. Differences between the national approaches to educational reforms are particularly reflected in the modes of education decentralisation, the level of school autonomy, accountability and funding mechanisms. We believe that different institutional arrangements may have contributed to the divergent achievements of the Czech Republic, Slovakia, Hungary and Poland in the PISA programme.  相似文献   
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The article forms an analysis of the religious discrimination discourse in Polish public schools, with special attention paid to the culturally specific, Polish understanding of the notion of religious discrimination. The introductory part presents the concept of religious discrimination as present in anti-discriminatory policies. The following part outlines the Polish system of religious education and its relation to the religious discrimination. Studies on religious discrimination in Poland are presented and discussed. Important context is supplied by a presentation of two recent cases of religious discrimination in Polish public schools, and the actions undertaken by the Freedom from Religion Foundation. Authors of the article point out the important influence of cultural context on the perception of religious discrimination. The attention is drawn to the seemingly homogenous environment of the Polish school and of the discriminative discourse used in political and social debates. The analysis shows that the presence of religion as a subject in Polish schools remains a cause of conflict between the religious and atheist citizens, a conflict in which concepts of religious discrimination and religious freedom are used as arguments by both sides.  相似文献   
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Mercury porosimetry was applied to the study of pore structure of the historic Roman cement mortars representative of different locations in Europe and time periods as well as different application techniques from architectural castings to in situ formed renders and profiles. Three categories of pores were found to coexist in the mortars. The finest pores, with diameters below 0.1 μm, are present within the hardened aged Roman cement matrix. The larger ‘air’ pores, with diameters between 0.2–2 μm, are due to the evaporation of the excess unbound water and restricted hydration. Pores larger than 2 μm are rare and, in general, can be related to microcracking induced by shrinkage drying and mortar weathering. The mortars have rarely been found to develop a dense fine-porous microstructure characteristic of the ideal conditions of moist-curing; massive architectural castings being the only exception identified. The presence of larger ‘air’ pores was, in turn, almost universally observed. The investigations of the freshly prepared Roman cement mortars have revealed that the restricted hydration could be due to the exposure of the freshly laid surface to dry real-world external environments, a high water-to-cement ratio in the original mortars, or the drawing of water from the stucco mass due to insufficient pre-wetting of the porous masonry. The insufficient reactivity of historic cements, resulting from a high content of over-burned, non-reactive cement components or coarseness of the cement grains, could be another reason for yielding poorly hydrated mortars in the past. In general, Roman cement stuccoes are in an excellent state of preservation in spite of their usual exposure to polluted urban environments for more than a century. Therefore, the coexistence of Roman cement mortars of widely different pore structures has not brought about any problems of incompatibility which field observations could reveal. The Roman cement repair materials have been found to develop pore structures similar to those of historic mortars. Therefore, they are in broad terms compatible with historic masonry or stuccoes. However, the porosity and strength of the repair materials can be controlled by a careful manipulation of the water-to-cement ratio of the mix to adapt them better to the properties of the host material.  相似文献   
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The aim of the study was to determine if sex differences exist in the key elbow and wrist joint injury risk factors during different cartwheel (CW) and round-off (RO) techniques performed by young male and female artistic gymnasts. Sixteen active young gymnasts (8 males and 8 females) performed 30 successful trials of CW and RO with three different hand positions (parallel (10), T-shape (10) and reverse (10)). Synchronised kinematic and kinetic data were collected for each trial. Two-way repeated measures ANOVA (3 × 2, technique × sex) and effect-sizes (ES) were used for statistical analysis. In conclusion, female gymnasts exhibited greater normalised peak vertical ground reaction forces (VGRF), elbow and wrist compression forces and elbow internal adduction moments during CW and RO skills compared with male gymnasts. In both sexes, the parallel and reverse techniques increased peak VGRF, elbow and wrist compression forces and the elbow internal adduction moment. Increased elbow flexion resulted in decreased peak VGRF, elbow compression forces and elbow internal adduction moment. Injury risk factors including elbow extension and internal adduction moment with axial compression force suggest that a CW and RO in reverse and parallel techniques can be hazardous especially for young female gymnasts.  相似文献   
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The development of peak performances is a main research focus in sports science. It is unclear how many former top junior athletes achieve success in the elite class later. The aim of the present study was to examine the careers of athletes who participated in major junior or adult/elite cycling events using prospective and retrospective analysis of competition results. The official results of major junior (age < or = 18 years) and elite (age > 18 years) cycling races from 1980 to 2004 were analysed. Age-related aspects, career lengths, and success were compared between riders who presented results in both junior and elite races (JUNIOR ELITE) and riders who had no junior race results (ELITE ONLY). Altogether, 27,454 results of 8004 athletes from 108 countries were collected. We found that 29.4% of the elite athletes had participated in junior World Championships, and that 34% of the participants in junior World Championships later participated in major elite competitions. JUNIOR ELITE athletes are significantly more successful in several cycling disciplines and have their first and last elite result at a younger age than ELITE ONLY athletes. No difference was found in career lengths. The data presented here emphasize the importance of long-term training programmes in the development of peak performance in cycling.  相似文献   
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The purpose of this study was twofold: (1) to determine the barbell load that maximised the system power as well as the ankle, knee, and hip joint powers during the squat jump, and (2) to compare the system powers computed from two different methods: the centre of mass (COM) method and the barbell method. Seven male throwers were recruited in this study. The system power (COM method) and the ankle, knee, and hip joint powers were determined with the load incrementally set at 0%, 10%, 30%, 50%, 70%, and 90% of one repetition maximum. The largest system power was observed at the load of 30% (p < 0.008) while the largest ankle and knee powers were observed at 70% and 0% (p < 0.05). The barbell method overestimated the system power (p < 0.001) when compared to the COM method. It was concluded that the barbell method could influence load optimisation in squat jump. The optimal barbell load which maximised the system power did not maximise the ankle, knee, or hip power simultaneously.  相似文献   
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