网络教育资源在化学研究性学习中的应用

一、问题的提出 新一轮基础教育课程改革提出:"大力推进信息技术在教学过程中的普遍运用,促进信息技术与学科课程的整合,逐步实现教学内容的呈现方式、学生的学习方式和师生互动方式的变革,倡导以自主、合作、研究为主多元学习方式".     

Biomechanical characteristics of adults walking forward and backward in water at different stride frequencies

The aim of this study was to examine spatiotemporal characteristics and joint angles during forward and backward walking in water at low and high stride frequency. Eight healthy adults (22.1 ± 1.1 years) walked forward and backward underwater at low (50 pulses) and high frequency (80 pulses) at the xiphoid process level with arms crossed at the chest. The main differences observed were that the participants presented a greater speed (0.58 vs. 0.85 m/s) and more asymmetry of the step length (1.24 vs. 1.48) at high frequency whilst the stride and step length (0.84 vs. 0.7 m and 0.43 vs. 0.35 m, respectively) were lower compared to low frequency (P < 0.05). Support phase duration was higher at forward walking than backward walking (61.2 vs. 59.0%). At initial contact, we showed that during forward walking, the ankle and hip presented more flexion than during backward walking (ankle: 84.0 vs. 91.8º and hip: 22.8 vs. 8.0º; P < 0.001). At final stance, the knee and hip were more flexed at low frequency than at high frequency (knee: 150.0 vs. 157.0º and hip: ?12.2 vs. –14.5º; P < 0.001). The knee angle showed more flexion at forward walking (134.0º) than backward walking (173.1º) (P < 0.001). In conclusion, these results show how forward and backward walking in water at different frequencies differ and contribute to a better understanding of this activity in training and rehabilitation.     

Effects of interval aerobic training combined with strength exercise on body composition,glycaemic and lipid profile and aerobic capacity of obese rats

The purpose of this study was to investigate the effects of interval aerobic training combined with strength exercise in the same training session on body composition, and glycaemic and lipid profile in obese rats. Sixteen lean Zucker rats and sixteen obese Zucker rats were randomly divided into exercise and sedentary subgroups (4 groups, n = 8). Exercise consisted of interval aerobic training combined with strength exercise in the same training session. The animals trained 60 min/day, 5 days/week for 8 weeks. Body composition, lipid and glycaemic profiles and inflammatory markers were assessed.

Results showed that fat mass was reduced in both lean and obese rats following the exercise training (effect size (95% confidence interval (CI)) = 1.8 (0.5–3.0)). Plasma low-density lipoprotein–cholesterol and fasting glucose were lower in the exercise compared to the sedentary groups (d = 2.0 (0.7–3.2) and 1.8 (0.5–3.0), respectively). Plasma insulin was reduced in exercise compared to sedentary groups (d = 2.1 (0.8–3.4)). Some exercise × phenotype interactions showed that the highest decreases in insulin, homeostatic model assessment-insulin resistance, fasting and postprandial glucose were observed in the obese + exercise group (all, P < 0.01). The findings of this study suggest that interval aerobic training combined with strength exercise would improve body composition, and lipid and glycaemic profiles, especially in obese rats.     

Development of perceived competence,tactical skills,motivation, technical skills,and speed and agility in young soccer players

ABSTRACT

The objective of this 1-year, longitudinal study was to examine the development of perceived competence, tactical skills, motivation, technical skills, and speed and agility characteristics of young Finnish soccer players. We also examined associations between latent growth models of perceived competence and other recorded variables. Participants were 288 competitive male soccer players ranging from 12 to 14 years (12.7 ± 0.6) from 16 soccer clubs. Players completed the self-assessments of perceived competence, tactical skills, and motivation, and participated in technical, and speed and agility tests. Results of this study showed that players’ levels of perceived competence, tactical skills, motivation, technical skills, and speed and agility characteristics remained relatively high and stable across the period of 1 year. Positive relationships were found between these levels and changes in perceived competence and motivation, and levels of perceived competence and speed and agility characteristics. Together these results illustrate the multi-dimensional nature of talent development processes in soccer. Moreover, it seems crucial in coaching to support the development of perceived competence and motivation in young soccer players and that it might be even more important in later maturing players.     

#OscarsSoWhite: how Stuart Hall explains why nothing changes in Hollywood and everything is changing

ABSTRACT

Stuart Hall’s work on culture, representation, ideology and hegemony positions Hollywood as a cultural institution informed by and informative of US social values and norms. Thus contemporary debates over Hollywood's diversity are indicative of broader social conflicts. Empirically the article examines 2014–2015 news coverage of Hollywood to question the Hollywood paradox—the lack of diversity in film/TV production yet TV’s increasing shift towards on-screen diversity. It maps three discursive frames: Hollywood exceptionalism, economic imperatives, and institutionalized racism and sexism. The article concludes by using Hulu’s East Los High to reflect on TV’s digital turn and innovative models in production and representation.     

To answer questions from text,one has to understand what the question is asking: differential effects of question aids as a function of comprehension skill

Reading and Writing - The present study investigates the effectiveness of question paraphrases in supporting students’ understanding of a specific task. Secondary school students (i.e.,...