应用RAPD技术研究阿尔卑斯山黄花茅居群内的遗传分化

应用RAPD技术,沿一个海拔梯度研究了阿尔卑斯山黄花茅自然居群的遗传变异和分化。实验 表明,虽然在亚居群间有很少的亚居群独有遗传标记的存在,但通过RAPD资料的聚类分析、主因子分  析以及相关分析观察到遗传分化沿海拔梯度发生,而且亚居群间的遗传分化和它们的海拔高度(地理距  离)呈有意义的正相关。研究结果暗示,在阿尔卑斯山的高山-亚高山过渡区,亚居群间的海拔高度差别  可能导致黄花茅开花和生长物候期的变化,而后者限制了亚居群间的基因流,从而引起居群内的遗传分化。     

Assessing the limitations of the Banister model in monitoring training

The aim of this study was to carry out a statistical analysis of the Banister model to verify how useful it is in monitoring the training programmes of elite swimmers. The accuracy, the ill-conditioning and the stability of this model were thus investigated. The training loads of nine elite swimmers, measured over one season, were related to performances with the Banister model. First, to assess accuracy, the 95% bootstrap confidence interval (95% CI) of parameter estimates and modelled performances were calculated. Second, to study ill-conditioning, the correlation matrix of parameter estimates was computed. Finally, to analyse stability, iterative computation was performed with the same data but minus one performance, chosen at random. Performances were related to training loads for all participants (R(2) = 0.79 +/- 0.13, P < 0.05) and the estimation procedure seemed to be stable. Nevertheless, the range of 95% CI values of the most useful parameters for monitoring training was wide: t(a) = 38 (17, 59), t(f) = 19 (6, 32), t(n) = 19 (7, 35), t(g) = 43 (25, 61). Furthermore, some parameters were highly correlated, making their interpretation worthless. We suggest possible ways to deal with these problems and review alternative methods to model the training-performance relationships.     

Effects of recombinant human erythropoietin injections on physical self in endurance athletes

This study examined the time course of mean self-esteem and physical self scores in three groups: male endurance athletes treated with recombinant human erythropoietin (rHuEPO group, n = 6), a placebo group (n = 5) injected with a sodium chloride solution and a control group who did not receive any injection (n = 6). Each participant completed the Physical Self Inventory twice a day (between 07.00 and 09.00 h and between 19.00 and 21.00 h). Using a 10 cm visual analog scale, the participants assessed global self-esteem, physical self-worth and the sub-domains of physical condition, sport competence, attractive body and physical strength (Fox & Corbin, 1989). This was conducted over three consecutive periods: in the 2 weeks before the course of injections, during the 6 weeks of injections and for 4 weeks after the injections. Aerobic capacity was assessed before and after 4 weeks of treatment. The results showed a significant increase in aerobic physical fitness in the rHuEPO group and a significant increase in perceived physical condition and physical strength scores at the end of treatment. The main psychological result was that endurance athletes were highly sensitive to the effects of rHuEPO on physical fitness. The perception of increased physical condition may lead to a stronger commitment to training. The rHuEPO injections presented a dangerous hedonic effect linked to endurance training. These results confirm the need to tackle rHuEPO abuse at any time during the training season.     

Impact of Background Music on Medical Student Anxiety and Performance During Anatomical Dissections: A Cluster Randomized Interventional Trial

Anatomical dissection on cadavers can be a source of anxiety for medical students. Studies in other stressful settings have shown a reduction in anxiety when there is background music. The objective of this study was to determine if music can have an impact on student anxiety, student satisfaction, and student performance in dissection room. This cluster randomized interventional trial included 187 second-year medical students. The intervention was standardized background music, selected based on the literature, with a tempo of between 60 and 80 bpm. Six balanced clusters were randomized (1:1) to music or no music during dissection sessions. The main assessment criterion was a validated self-evaluation scale score for anxiety, the State Trait Anxiety Inventory. Student satisfaction was measured using a visual analog scale and dissection performance was evaluated by an examination. The outcomes were analyzed with mixed models adjusted on group effect, chronic anxiety, and confounding factors. A significant (58%) relative decrease in acute anxiety, odds ratio 0.423 [0.160; 0.710] was found for the music intervention group. Music also had a positive impact on performance with students in the intervention group attaining higher grades than those in the control group (0.42/10 higher, P = 0.0016). The study also showed a nonsignificant increase in satisfaction with 0.37 extra points (P = 0.137) in the intervention group. Background music had a significant impact on anxiety in the dissection room and on technical and theoretical performance in the subsequent anatomy examination. This music intervention could be extended to other stressful work environments.     

Comparative outcomes of two instructional models for students with learning disabilities: inclusion with co‐teaching and solo‐taught special education

We compared two instructional models (co‐teaching inclusion and solo‐taught special education) for students with learning disabilities (LD) with regard to their effect on academic achievement and class attendance. Twelve inclusive classes (experimental group) and 13 special education classes (control group) participated in the study. In grade 1, there were eight inclusive classes and nine special education classes with a total of 353 students (195 without disabilities, 58 with LD in inclusion and 100 with LD in special education classes). The data were collected from academic tests. Although our results revealed no significant difference between the two models in terms of target population, objectives and assigned resources, significant differences were observed in the effects on student outcomes in reading/writing and on attendance, as the inclusion model was shown to be globally more effective compared with the special education setting.     

Europe Versus Emerging Countries Within FIFA: Using Inflation as a Conflict Regulation Mechanism

Abstract

As is the case within many international organizations, Fédération Internationale de Football Association (FIFA) is beset by internal tensions between the North, those nations which have historically held most power, and the South, mainly African and Asian countries, which look forward to a more balanced functioning. The numerous conflicts which arise in the governing body of association football usually takes the form of an opposition between regional confederations. The purpose of this article is to show that the regulation of these disputes may be considered as inflationist. The technique of playing on nominal factors such as the number of places in the executive committee or the number of countries participating the world cup can lead to concessions on real power sharing. This tactic is therefore used in FIFA when feasible.     

Entrepreneurial innovation: The importance of context

The purpose of this article and the special issue is to improve our understanding of the theoretical, managerial, and policy implications of entrepreneurial innovation. We accomplish this objective by examining the role of context in stimulating such activity, as well as its impact on the outcomes of entrepreneurial innovation. Our analysis begins by outlining an overarching framework for entrepreneurial innovation and context. With reference to this framework we then compare the attributes of national innovation systems, entrepreneurship and entrepreneurial innovation, and categorize contextual influences on entrepreneurial innovation. We then situate the papers presented in this special issue within this framework. We conclude by outlining an agenda for additional research on this topic, focusing on the relationships between contexts and entrepreneurial innovation and then discuss policy implications, focusing on how public and private actors can meet these challenges.     

Data-driven estimates of global nitrous oxide emissions from croplands

Croplands are the single largest anthropogenic source of nitrous oxide (N₂O) globally, yet their estimates remain difficult to verify when using Tier 1 and 3 methods of the Intergovernmental Panel on Climate Change (IPCC). Here, we re-evaluate global cropland-N₂O emissions in 1961–2014, using N-rate-dependent emission factors (EFs) upscaled from 1206 field observations in 180 global distributed sites and high-resolution N inputs disaggregated from sub-national surveys covering 15593 administrative units. Our results confirm IPCC Tier 1 default EFs for upland crops in 1990–2014, but give a ∼15% lower EF in 1961–1989 and a ∼67% larger EF for paddy rice over the full period. Associated emissions (0.82 ± 0.34 Tg N yr^–1) are probably one-quarter lower than IPCC Tier 1 global inventories but close to Tier 3 estimates. The use of survey-based gridded N-input data contributes 58% of this emission reduction, the rest being explained by the use of observation-based non-linear EFs. We conclude that upscaling N₂O emissions from site-level observations to global croplands provides a new benchmark for constraining IPCC Tier 1 and 3 methods. The detailed spatial distribution of emission data is expected to inform advancement towards more realistic and effective mitigation pathways.