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11.
It is commonly assumed that sport plays an important role for national identity. However, empirical research has primarily focused on sport’s role for emotional-affectice rather than cognitive aspects of national identity. Therefore, research presented here explores whether identification with the German national soccer team serves to reinforce ethnic or civic conceptions of national identity. Analyses of a unique dataset conducted during the 2014 FIFA World Cup and the 2016?EURO show that national team identification is an important determinant of national pride and national belonging. Respondents who identify with the national soccer team can adhere to different conceptions of national identity. It seems that national pride and affection as well as conceptions of national identity represent stable attitudes not affected by the success of the national team. Further research should improve conceptual clarity and measurement.  相似文献   
12.
ABSTRACT

Previous studies investigating the relationship between motor skill, physical activity and fitness in children have not thoroughly considered the role of self-perception. Therefore, the study aim was to test a theoretical framework, which considered both actual and perceived motor skill as well as actual and perceived fitness. Potential moderating effects of sex and country were considered. Data on motor skill, fitness, as well as self-perception of motor skill and fitness were collected from 145 Australian children and 214 German children (age range 7 to 10 years). For actual motor skill and fitness, mean differences for sex, age and country were found. For perceived motor performance (perceived motor skill and perceived fitness) no mean differences were found for age. Path analyses were performed. The final model showed significant relations between actual performance (object control skill, fitness) and perceived performance (object control skill, fitness). All model paths had low to moderate regression weights with the lowest relationship reported between actual and perceived fitness. Sex and country showed no effects. This integrated approach has led to a better understanding of the relationship between children’s perceived and objective performance, and cultural differences within them.  相似文献   
13.
The manipulation of ribosomal RNA (rRNA) extracted from E. coli cells by dielectrophoresis (DEP) has been demonstrated over the range of 3 kHz-50 MHz using interdigitated microelectrodes. Quantitative measurement using total internal reflection fluorescence microscopy of the time dependent collection indicated a positive DEP response characterized by a plateau between 3 kHz and 1 MHz followed by a decrease in response at higher frequencies. Negative DEP was observed above 9 MHz. The positive DEP response below 1 MHz is described by the Clausius-Mossotti model and corresponds to an induced dipole moment of 3300 D with a polarizability of 7.8×10(-32) F m(2). The negative DEP response above 9 MHz indicates that the rRNA molecules exhibit a net moment of -250 D, to give an effective permittivity value of 78.5 ε(0), close to that of the aqueous suspending medium, and a relatively small surface conductance value of ~0.1 nS. This suggests that our rRNA samples have a fairly open structure accessible to the surrounding water molecules, with counterions strongly bound to the charged phosphate groups in the rRNA backbone. These results are the first demonstration of DEP for fast capture and release of rRNA units, opening new opportunities for rRNA-based biosensing devices.  相似文献   
14.
Repeated physical contact in rugby union is thought to contribute to post-match fatigue; however, no evidence exists on the effect of contact activity during field-based training on fatigue responses. Therefore, the purpose of this study was to examine the effect of contact during training on fatigue markers in rugby union players. Twenty academy rugby union players participated in the cross-over study. The magnitude of change in upper- and lower-body neuromuscular function (NMF), whole blood creatine kinase concentration [CK] and perception of well-being was assessed pre-training (baseline), immediately and 24?h post-training following contact and non-contact, field-based training. Training load was measured using mean heart rate, session rating of perceived exertion (sRPE) and microtechnology (Catapult Optimeye S5). The inclusion of contact during field-based training almost certainly increased mean heart rate (9.7; ±3.9%) and sRPE (42; ±29.2%) and resulted in likely and very likely greater decreases in upper-body NMF (?7.3; ±4.7% versus 2.7; ±5.9%) and perception of well-being (?8.0; ±4.8% versus ?3.4; ±2.2%) 24?h post-training, respectively, and almost certainly greater elevations in [CK] (88.2; ±40.7% versus 3.7; ±8%). The exclusion of contact from field-based training almost certainly increased running intensity (19.8; ±5%) and distance (27.5; ±5.3%), resulting in possibly greater decreases in lower-body NMF (?5.6; ±5.2% versus 2.3; ±2.4%). Practitioners should be aware of the different demands and fatigue responses of contact and non-contact, field-based training and can use this information to appropriately schedule such training in the weekly microcycle.  相似文献   
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We present statistical tests for departures from random expectation in spatial memory tasks. We consider two common protocols for spatial memory experiments. In the first one, subjects are allowed to search a fixed number of sites. In the second protocol, subjects are allowed to search until they achieve a fixed number of successes. In either of these protocols, the subjects involved may or may not revisit sites that have been previously searched or exploited. This yields four situations to consider: fixed number of sites searched or fixed number of successes, with or without revisits. We derive analytical expressions for the probability mass functions, expectations, and variances associated with each type of null hypothesis. We present three statistical tests of these hypotheses: the Kolmogorov-Smirnov test, the ordinary sign test, and theZ test. We use our results to demonstrate a priori calculation of sample sizes and statistical power and to consider a mixed model of sampling with and without replacement.  相似文献   
17.
This study examines associations between childhood maltreatment and developmental trajectories of sexual risk behaviors (SRBs) in a sample of 882 sexually active adolescent girls, predominantly Hispanic or Black, assessed every 6 months between 13 and 23 years. Latent profile analyses revealed four distinct maltreatment profiles: Low Maltreatment (76%), Moderate Emotional Neglect Only (15%), Severe Physical/Emotional Abuse (3%), and Severe Sexual Abuse (6%). Multilevel growth analyses showed the Moderate Emotional Neglect Only and Severe Sexual Abuse profiles exhibited more SRBs starting in late adolescence, and the Severe Sexual Abuse profile also exhibited a faster increase than the Low Maltreatment profile. Understanding heterogeneity within maltreated populations may have important implications for healthy sexual development.  相似文献   
18.
This study investigated the changes in measures of neuromuscular fatigue and physical performance in young professional rugby union players during a preseason training period. Fourteen young (age: 19.1?±?1.2 years) professional rugby union players participated in the study. Changes in measures of lower body neuromuscular fatigue (countermovement jump (CMJ) mean power, mean force, flight-time) and physical performance (lower body strength, 40?m sprint velocity) were assessed during an 11-week preseason period using magnitude-based inferences. CMJ mean power was likely to very likely decreased during week 2 (?8.1?±?5.5% to ?12.5?±?6.8%), and likely to almost certainly decreased from weeks 5 to 11 (?10?±?4.3% to ?14.7?±?6.9%), while CMJ flight-time demonstrated likely to very likely decreases during weeks 2, and weeks 4–6 (?2.41?±?1% to ?3.3?±?1.3%), and weeks 9–10 (?1.9?±?0.9% to ?2.2?±?1.5%). Despite this, possible improvements in lower body strength (5.8?±?2.7%) and very likely improvements in 40?m velocity (5.5?±?3.6%) were made. Relationships between changes in CMJ metrics and lower body strength or 40?m sprint velocity were trivial or small (<0.22). Increases in lower body strength and 40?m velocity occurred over the course of an 11-week preseason despite the presence of neuromuscular fatigue (as measured by CMJ). The findings of this study question the usefulness of CMJ for monitoring fatigue in the context of strength and sprint velocity development. Future research is needed to ascertain the consequences of negative changes in CMJ in the context of rugby-specific activities to determine the usefulness of this test as a measure of fatigue in this population.  相似文献   
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20.
中国最近提出的减少海外投资的计划并不是跨国企业在中国大陆面临的唯一威胁。在中国政府频频修改其监管框架的同时,一个庞大的、定价格外低廉而质量却可以接受的低端产品领域正在悄然形成。这个“够用就好”(Good-Enough)的市场冲击着公司原本想将中国作为低成本加工中心,或者向中国不断走向富裕的消费者销售优质产品的想法。  相似文献   
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