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1.
Adverse effects of energy restriction on myogenic enzymes in judoists   总被引:1,自引:1,他引:0  
In this study, we examined the effects of weight reduction by restricting energy intake on muscle function and serum concentrations of myogenic enzymes in judoists. Twenty-seven male judoists aged 19.3 +/- 0.6 years (mean +/- s) were divided into three groups based on the extent of body weight reduction: high weight reduction (height 1.70 +/- 0.05 m, body mass 78.5 +/- 13.6 kg), low weight reduction (height 1.70 +/- 0.05 m, body mass 80.7 +/- 13.1 kg) and a group that maintained body weight while continuing to perform exercise training (height 1.78 +/- 0.07 m, body mass 78.7 +/- 8.8 kg). Body composition, blood biochemistry, energy intake and anaerobic power were assessed on four occasions: 20 days (baseline data), 4 days and 1 day before and 7 days after competition. Compared with baseline, body mass and fat-free mass were significantly lower 1 day before competition in the high and low weight reduction groups (both P < 0.01); these changes persisted for 7 days after competition in the high weight reduction group. Serum creatine kinase was significantly elevated 1 day before competition in all groups (all P < 0.05), and remained higher 7 days after competition in both the high and low weight reduction groups. Compared with baseline, maximal anaerobic power was significantly lower 1 day before competition only in the high weight reduction group (P < 0.01). Our results suggest that energy restriction in addition to intense exercise training before major competition has an adverse effect on anaerobic power and elevates serum creatine kinase concentration, leading to an impairment of muscular function and an increased susceptibility of muscle tissue to injury.  相似文献   
2.
The spatial concentration distribution of cells in a microchannel is measured by combining the dielectric properties of cells with the specific structure of the electrode-multilayered microchannel. The dielectric properties of cells obtained with the impedance spectroscopy method includes the cell permittivity and dielectric relaxation, which corresponds to the cell concentration and structure. The electrode-multilayered microchannel is constructed by 5 cross-sections, and each cross-section contains 5 electrode-layers embedded with 16 micro electrodes. In the experiment, the dielectric properties of cell suspensions with different volume concentrations are measured with different electrode-combinations corresponding to different electric field distributions. The dielectric relaxations of different cell concentrations are compared and discussed with the Maxwell-Wagner dispersion theory, and the relaxation frequencies are analysed by a cell polarization model established based on the Hanai cell model. Moreover, a significant linear relationship with AC frequency dependency between relative permittivity and cell concentration was found, which provides a promising way to on-line estimate cell concentration in microchannel. Finally, cell distribution in 1 cross-section of the microchannel (X and Y directions) was measured with different electrode-combinations using the dielectric properties of cell suspensions, and cell concentration distribution along the microchannel (Z direction) was visualized at flowing state. The present cell spatial sensing study provides a new approach for 3 dimensional non-invasive online cell sensing for biological industry.  相似文献   
3.
The interactions of 67 early childhood preservice teachers with International and U.S. preschool children in structured story time and unstructured table activities were videotaped and analyzed. Overall, preservice teachers displayed significantly more facilitative (e.g., ego boosting, teaching, questioning, and attending) than nonfacilitative (e.g., commanding, negatively responding, ignoring, and physical restraint) behaviors toward children. However, analyses of data relative to different ethnicity, gender, and activity type groups also revealed preservice teachers were relating to children in differential ways. Preservice teachers displayed significantly less facilitative and more nonfacilitative behaviors toward International children than U.S. children. In addition, preservice teacher‐child interactions with International children were rated as less positive and more negative than their interactions with U.S. children. Still also, preservice teachers displayed significantly less facilitative and less nonfacilitative behaviors toward girls than toward boys. Furthermore, preservice teacher‐child interactions with girls were rated as significantly less positive and less negative than with boys. Finally, preservice teachers displayed significantly more nonfacilitative behaviors toward children in structured story time activities than in unstructured table activities.  相似文献   
4.
Previously, K.A. Dodge and colleagues found an association between hostile attributional bias and aggressive behaviors among school aged children. The present study explored such an association among preschool aged children. Sixty-eight children (38 girls and 30 boys) with a mean age of 4.76 years participated in the study. Videotaped vignettes of children's social interactions were developed specifically for this age group to examine their attributional bias. Children's aggressive behaviors were assessed by teachers, using the Preschool Behavior Questionnaire. Results indicated that hostile/aggressive children were significantly more likely to possess a hostile attributional bias (p < .05) than less aggressive children. Results also indicated that preschoolers were capable of distinguishing between intentional and unintentional actions when stimulus materials used were concrete and familiar to them.  相似文献   
5.
This study investigated whether 2-, 3-, and 4-year-olds use their video feedback as a reflection of their current state, even when their feedback was presented with a short temporal delay. In Experiment 1, the effects of 1- and 2-s delayed feedback were examined on an analog of the mark test. In the case of live and 1-s delayed feedback, 3-year-olds passed the test; however, they failed in the case of 2-s delayed feedback. Experiment 2 examined the effect of prior experience of delayed contingency and explorative behavior. The results showed a significant effect of prior experience. These results suggest that detection of visual-proprioceptive contingency contributes to recognition of visual feedback as one's current self.  相似文献   
6.
Abstract

In this article, we examine the integration of science and mathematics teaching in early childhood education. We explore the meaning of integration and offer a rationale for integrating science and mathematics methods classes for pre‐service teachers. The case is made that pre‐service teachers should develop an understanding of the connections between mathematics and science so that they can be better prepared to teach with an emphasis on the connections between these two content areas.  相似文献   
7.
In this study, we examined the effects of weight reduction by restricting energy intake on muscle function and serum concentrations of myogenic enzymes in judoists. Twenty-seven male judoists aged 19.3±0.6 years (mean±s) were divided into three groups based on the extent of body weight reduction: high weight reduction (height 1.70±0.05?m, body mass 78.5 ±13.6?kg), low weight reduction (height 1.70±0.05?m, body mass 80.7±13.1?kg) and a group that maintained body weight while continuing to perform exercise training (height 1.78± 0.07?m, body mass 78.7±8.8?kg). Body composition, blood biochemistry, energy intake and anaerobic power were assessed on four occasions: 20 days (baseline data), 4 days and 1 day before and 7 days after competition. Compared with baseline, body mass and fat-free mass were significantly lower 1 day before competition in the high and low weight reduction groups (both P?<0.01); these changes persisted for 7 days after competition in the high weight reduction group. Serum creatine kinase was significantly elevated 1 day before competition in all groups (all P?<0.05), and remained higher 7 days after competition in both the high and low weight reduction groups. Compared with baseline, maximal anaerobic power was significantly lower 1 day before competition only in the high weight reduction group (P?<0.01). Our results suggest that energy restriction in addition to intense exercise training before major competition has an adverse effect on anaerobic power and elevates serum creatine kinase concentration, leading to an impairment of muscular function and an increased susceptibility of muscle tissue to injury.  相似文献   
8.
This study contributes to the debate on the role of openness to international markets for the diffusion of compliance with international standards in developing countries. Relying upon aggregated data for 1995-2005, as well as upon firm-level and secondary data from the Chilean salmon farming industry, the determinants of ISO 9000 and ISO 14001 diffusion at country, industry, and firm level, in Latin American are analysed. Our evidence suggests that openness to international markets acts at different levels. At both the country and industry level, it creates awareness and access to new knowledge therefore providing economic incentives or penalisations for evaluating certification. This effect competes and complements the deliberated efforts and policies in explaining diffusion of certification. At firm level, however, openness to international markets alone does not provide sufficient opportunities to acquire the knowledge required to comply with these standards. In this case, standards’ compliance depends on firm's capability to use relational and search assets, as well as on national and industrial efforts and policies to spread standards’ usage.  相似文献   
9.
Reading and Writing - Efforts to improve classroom language practices and children’s language learning, as a means of supporting reading comprehension, may depend on teachers’ knowledge...  相似文献   
10.
To clarify the physical and mental fatigue caused by intense exercise and the relationship between the two types of fatigue, we examined changes in anthropometric and biochemical variables, neutrophil function, and the Profile of Mood States (POMS) questionnaire in 13 female university judoists attending a one-week training camp. Blood glucose, total cholesterol, haemoglobin, leukocyte count, IgG, and phagocytic activity all decreased after the training camp compared with baseline (P < or = 0.046). Aspartate aminotransferase, lactate dehydrogenase, creatine kinase, and neutrophil oxidative burst activity increased after the training camp (P < or = 0.007). Of the POMS scores, that for Fatigue increased after the training camp (P = 0.041) and that for Vigour decreased (P = 0.042). The changes in several POMS scores correlated with the changes in blood biochemical variables. In particular, the change in Total mood disturbance was negatively associated with changes in myogenic enzymes (P < or = 0.032). Our results suggest that intense exercise during training camps for female judoists leads to the appearance and accumulation of mental and physical fatigue, which are related to each other.  相似文献   
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