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41.
摘要:目的:高原因其特殊环境,世居平原运动员初上高原训练时机体会产生一系列应激反应。借助代谢组学技术,从急性应激和慢性适应2个纬度,比较分析高原训练初期运动员代谢功能所发生的改变。方法:以16名优秀赛艇运动员为研究对象,在高原训练前、年度高原冬训的第4天、第14天调整休息后次日晨取肘静脉血5 mL,分离血浆,借助LC-MS平台测量分析各血浆代谢物,以PCA、OPLS-DA比较各时间点代谢谱的变化。高原训练初期的主要训练内容为低强度有氧训练。结果:1)与高原训练前比较,高原第4天和高原第14天发生显著改变的血浆代谢物各有近80种:a)与高原训练前比较,高原训练第4天血浆苯甲酰胺、吲哚-3-乙醛分别升高约35倍、17倍,血浆苯乙胺、苯酚、吲哚等分别升高约4-8倍;b)高原训练第14天与高原训练前相比,血浆苯甲酰胺、吲哚-3-乙醛、苯乙胺、吲哚等显著升高约2-6倍;血浆胆固醇羟化硫酸酯、色氨酸、3-(4-羟基-3-甲氧基苯基)-2-氧丙酸等下降约2-8倍。2)与高原训练前比较,高原训练第4天苯丙氨酸、色氨酸代谢显著加强,同时,苯丙氨酸、酪氨酸、色氨酸、氨酰-tRNA生物合成显著增加,但不饱和脂肪酸的生物合成显著下调;高原第14天,苯丙氨酸、酪氨酸代谢显著加强,同时,苯丙氨酸、酪氨酸、色氨酸、氨酰-tRNA生物合成仍显著增加,不饱和脂肪酸的生物合成显著下调;高原第14天与高原第4天比较,氨酰-tRNA、缬氨酸,亮氨酸、异亮氨酸生物合成显著上调,而不饱和脂肪酸的生物合成显著下调,精氨酸、脯氨酸代谢加强。结论:优秀赛艇运动员高原训练急性应答期,参与中枢神经系统能量代谢调控的苯甲酰胺、吲哚-3-乙醛升高达数十倍,之后升高幅度下降,可能是高原训练初期代谢适应的敏感标志物。中枢神经系统的应激与适应可能在运动员高原训练初期代谢应答中发挥着关键作用。高原训练初期芳香族氨基酸、支链氨基酸代谢较为活跃,不饱和脂肪酸代谢抑制,其确切调节机制尚待深入研究。  相似文献   
42.
Little is known regarding the profiles of whole body donors in Muslim majority countries where donation is scarce. Therefore, this study aims to profile registered donors in Turkey by means of a survey. The explored data could be used to improve ongoing campaign efforts and ethical practices such as commemoration services. Registered donors of the donation programs at the two faculties of medicine of Istanbul University were compared with the national population and a cluster analysis was performed to reveal any concealed sub-groups. Data from 188 respondents were analyzed. The majority of registered donors were married (42%), male (65.4%), aged over 50 years (76%), held a tertiary education degree (49.7%), and were irreligious (58.5%). Cluster analysis revealed two groups with significantly different educational levels, marital statuses, and religious choices. Regarding whether their bodies could be used for education or research, the majority (64.5%) of the respondents left the decision to the anatomy department. Similarly, 73.8% approved indefinite use of their organs, body parts and/or skeletons. The respondents were also willing to share their medical history (94.2%) and personal information (81.6%) if needed. Motivational themes for body donation including usefulness, impermanence, religion, awareness, and kinship were devised after a thematic analysis. Among the respondents, 56.5% were registered organ donors and 63.3% were frequent blood donors. The results of this study provide data that may help revising informed consent forms, developing and implementing thanksgiving ceremonies, and selecting additional targets for supporting body donation campaign activities such as organ and blood donation units.  相似文献   
43.
Divergent Thinking is a domain-general mental attribute closely associated with creativity that can be quantified through the use of text-mining algorithms. Past research has shown that students’ Divergent Thinking is malleable in response to relatively simple contextual prompts. In addition, there is substantial variance in the degree to which individual students’ Divergent Thinking is malleable, suggesting the presence of a student-specific zone-of-proximal-development in relation to creativity. Here, we adopted a dynamic assessment paradigm that included multiple conditions under which student Divergent Thinking was measured and fit a latent profile analysis model to that dynamic assessment data. We found that, although on average the Originality of student responses can be augmented through a prompt to generate surprising or unusual ideas, three latent classes emerged that differed significantly on their patterns of augmentation. These three latent classes were termed: (a) Conventional Thinkers (7.80% of the sample), whose response to the Divergent Thinking task were highly constrained and unoriginal across all conditions (b) Prompted Shifters (66.56%), whose Originality significantly increased across conditions, and (c) Idea Generators (25.64%), whose responses were highly original across all conditions. These latent profiles were validated in regard to personality characteristics and domain-specific creative activities, with Idea Generators reporting significantly more Openness and Intellect, less Industriousness, and more creative activities across the domains of Literature, Music, Sports, Visual Art, Science, and Cooking than did the other latent classes.  相似文献   
44.
BackgroundResearch on achievement goal orientations in sport has typically relied on the use of variable-centered approaches that tend to overlook population heterogeneity. In this study, we used a person-centered approach to identify subgroups of competitive tennis players according to unique combinations of achievement goal orientations and tested for subgroup differences in motivation and mental toughness.MethodsA sample of 323 competitive tennis athletes (69.35% male) between 15 and 25 years of age (17.60 ± 2.40 years, mean ± SD) completed the 3 × 2 Achievement Goal Questionnaire for Sport, Sport Motivation Scale II, and Mental Toughness Index. Latent profile analysis was used to identify unique combinations of achievement goal orientations. Comparisons between latent subgroups on autonomous motivation, controlled motivation, and mental toughness were performed using analysis of variance.ResultsLatent profile analysis supported 3 distinct patterns of achievement goal profiles that were primarily distinguishable based on valence of competence (i.e., approach vs. avoidance). Analyses of variance indicated that athletes who were classified into subgroups that endorsed approach types of goals (regardless of the types of avoidance goals they endorsed) reported higher levels of autonomous motivation and mental toughness.ConclusionResults indicated that athletes tend to pursue a number of achievement goals collectively rather than in isolation. Although approach goals are more commonly linked to adaptive psychological functioning and positive outcomes, avoidance goals may also be associated with desirable psychological characteristics if they are pursued in conjunction with approach types of achievement goals.  相似文献   
45.
ABSTRACT

The effectiveness of 8-week force-velocity optimised training was assessed in highly trained professional rugby league athletes. Players (age 24 ± 3 years; body mass 94.9 ± 21.6 kg; height 181.3 ± 6.0 cm) were strength-matched and assigned to a force-velocity optimised group (OP; n = 15) or a general strength-power group (GP; n = 14). Tests included 10-m, 20-m sprints, 3 repetition-maximum squat and squat jumps over five load conditions to ascertain vertical force-velocity relationship. ANCOVA revealed there was a group effect for force-velocity deficit (P < 0.001), with the OP two-fold greater than the GP group (OP pre: 51.13 ± 31.42%, post: 62.26 ± 31.45%, GP pre: 33.00 ± 19.60%, post: 31.14 ± 31.45%, P < 0.001). There were further group effects for 3RM squat (OP pre: 151.17 ± 22.95 kg, post: 162.17 ± 24.16 kg, GP pre: 156.43 ± 25.07 kg, post: 163.39 ± 25.39 kg, P < 0.001), peak power (OP pre: 3195 ± 949 W, post: 3552 ± 1033 W, GP pre: 3468 ± 911 W, post: 3591 ± 936 W, P < 0.001), and SJ (OP pre: 39.79 ± 7.80 cm, post: 42.69 ± 7.83 cm, GP pre: 40.44 ± 6.23 cm, post: 41.14 ± 5.66 cm, P < 0.001). Prescribing F-V deficit training is superior for improving physical performance within highly trained RL players.  相似文献   
46.
In the Greek publishing industry, tradition and the desire for innovation go hand in hand. The industry is influenced by European developments in publishing and bookselling in terms of book promotion methods, the role of chain bookstores and the impact of information technology. Greece shares the features of other small book markets in Europe, whilst retaining the individuality defined by the Greek language and the country’s cultural and social conditions. This article provides an overview of the publishing industry in Greece through a review of the relevant literature and the available statistics. This work also focuses on the need to develop publishing skills through publishing education and continuous professional development.  相似文献   
47.
幼儿园管理是影响幼儿园保教质量的重要因素。本研究采用分层抽样的方法,从我国5个省份选取了100所不同性质的城乡幼儿园,利用《走向优质——中国幼儿园教育质量评价标准》中的“管理引领”子标准对其管理质量进行研究。结果发现我国幼儿园管理质量整体处于中等偏下水平,其中“自评改进”项目得分最低。同时,潜在剖面分析的结果显示,我国幼儿园管理质量存在3种潜在类别,即“管理质量不适宜”型(10%)、“管理质量合格”型(72%)和“管理质量良好”型(18%)。进一步的线性回归和logistics回归分析结果表明,幼儿园的办园性质、所在地区和班级数量能够预测幼儿园的管理质量水平。与非城区幼儿园相比,城区幼儿园更不可能成为“管理质量不适宜”和“管理质量合格”型的幼儿园。与民办性质的幼儿园相比,公办性质的幼儿园成为“管理质量不适宜”型幼儿园的可能性更低。今后应加强对幼儿园管理质量的研究,持续改进幼儿园管理质量,重点关注和支持可能成为“管理质量不适宜”型的幼儿园。  相似文献   
48.
The increasing importance of constructivism in higher education has brought about a shift in pedagogy from a focus on the teacher to a focus on the student. This has important implications for teaching and assessment. A student-centred pedagogy implies a different role for the teacher. What exactly does student-centred teaching require from teachers’ actual teaching practice? What is expected from them in order to teach in a student-centred way? It is in order to respond to these questions that this research project has been carried out establishing a core competence profile of student-centred teachers in higher education. Qualitative data were collected by means of semi-structured in-depth interviews with teachers from different institutions for higher education in Belgium, known for their student-centred way of teaching. This research method is innovative compared to the methods used for existing competence lists in the literature, which were usually developed on the basis of conversations with pedagogical experts. By exploring practice and having teachers participate in the development of a competence list, the acceptance of a competence profile is much higher. The result of the project is a validated competence profile which takes into account the critiques on existing competence lists. The competence profile provides a further insight in the functioning of teachers within a student-centred pedagogy and can be used as a starting point for the educational development of teachers within this pedagogy.  相似文献   
49.
The need to enhance the STEM workforce and, in turn, the STEM educational pipeline is a prevailing issue in the U.S. One critical component in this pipeline is students’ interest in STEM majors and their persistence in such majors, theorized to be a function of both students’ perceived value and expectancy beliefs in the subject matter. Using an expectancy-value lens, we examined cross-domain patterns of high school students’ expectancy beliefs and values in both mathematics and science using a person-centered or profile approach. With data from the High School Longitudinal Study, latent profile analysis revealed five profiles characterized as Low Math/Low Science (i.e., endorsing low levels of expectancy and value beliefs in math and science), Moderate Math/Moderate Science, High Math/High Science, Low Math/High Science, and High Math/Low Science. Taking into account aspects of students’ background and school context, we found that motivational profile membership predicted math and science high school achievement, college persistence, and both STEM major intentions and major choices. Moreover, there were a number of gender and racial/ethnic differences and contextual variation in profile memberships as well. Implications for theory and educational practice are discussed in relation to study findings.  相似文献   
50.
1 Introduction a Compton scattering is well known, and its applications are studied by physicists, chemists and specialists in many fields. Some applications are relatively mature and relevant instruments have been developed such as ComScan; whereas the o…  相似文献   
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