Mensch und Freizeit Internationale Werktagung in Salzburg,Juli 1961

Ohne Zusammenfassung     

Relationship Between Teacher Factors and Student Achievement： A Correlational Study of Secondary Schools

Teachers always played a significant role in the intellectual and moral development of students by using various techniques, assessments, and methods to improve student achievement in school＇s subjects. This study therefore focuses on the effect of teacher factors, such as assessment interval, communication language, the distance of residence, and the teacher＇s personal characteristics （gender, age, academic and professional qualification, designation, experience, and in-service training） on the 9th grade students＇ achievement in three subjects （English, Chemistry, and Mathematics at secondary level）. The population of the study is comprised of all ＂public sector＂ secondary schools, male and female teachers, and boy and girl students. A total number of 16 secondary schools （eight for boys and eight for girls）, 114 secondary school teachers （66 males and 48 females）, and 2,404 students （1,400 boys and 1,004 girls） were selected through purposive sampling techniques. Multiple statistical procedures, Spearman and Pearson correlation, mean, and standard deviation were employed to obtain stronger validity to the study. The results of the study identify weak and negative weak relationship between most of the teacher factors and student achievement in three subjects but the relationship between students＇ background and learning achievement in all three subjects were found positively correlated.     

Book selection strategies in university libraries of Pakistan: An analysis

University libraries in Pakistan spend a large portion of their funds on buying books and these are still the most important part of libraries' collections. Selection policies and practices play fundamental role in developing a strong book collection. This study aims to explore the policies, methods and procedures of selecting books in the university libraries of Pakistan. Data for the study were collected following multi-method approach, through questionnaires and unstructured interviews with the university librarians and faculty members for the doctoral research by the present author during 2003 to 2004. The analysis of data shows that the factors affecting successful execution of the practice of effective selection include: overly dependence on the faculty for selection, constraints of faculty members as selectors, non-availability of selection aids, lack of awareness regarding online resources available for selection, etc. The study suggests some feasible ways to improve the situation. The findings and suggestions may be of value to the countries with similar situations in the developing world.     

Pädagogische Zeitschriften Österreichs

Ohne Zusammenfassung     

Intermittent hypoxia does not affect endurance performance at moderate altitude in well-trained athletes

Abstract

In this study, we examined the effects of a pre-acclimatization programme on endurance performance at moderate altitude using a resting intermittent hypoxia protocol. The time-trial performance of 11 cyclists was determined at low altitude (600 m). Athletes were randomly assigned in a double-blind fashion to the hypoxia or the control group. The pre-acclimatization programme consisted of seven sessions each lasting 1 h in normobaric hypoxia (inspired fraction of oxygen of 12.5%, equivalent to approximately 4500 m) for the hypoxia group (n = 6) and in normoxia (inspired fraction of oxygen of 20.9%) for the control group (n = 5). The time-trials were repeated at moderate altitude (1970 m). Mean power output during the time-trial at moderate altitude was decreased in the hypoxia group (?0.26 ± 0.11 W · kg^?1) and in the control group (?0.13 ± 0.04 W · kg^?1) compared with at low altitude but did not differ between groups (P = 0.13). Our results suggest that the applied protocol of intermittent hypoxia had no positive effect on endurance performance at moderate altitude. Whether different intermittent hypoxia protocols are advantageous remains to be determined.     

The association between financial aid availability and the college dropout rates in Colombia

The main objective of this study is to estimate the association between financial aid and college dropout rates of postsecondary students in Colombia. We use a unique dataset from the Colombian Ministry of Education that includes all enrolled college students in the country between 1998 and 2008. Logistic regression is used to identify the correlation between receiving different forms of financial aid on the dropout rates of the students. The main results of the study suggest that the probability of dropping out decrease between 25 and 29% according to the type of financial aid received. There is also evidence that the financial aid is more effective in reducing dropout rates at the beginning of the student’s college careers. This result holds after controlling by type of postsecondary institution attended. These findings suggest that financial aid is an effective tool to reduce dropout rates, and therefore increase persistence and expand access in Colombia.     

丹尼尔论远程教育基础(下)

该文考查了远程教育的基础,它的发展历史和它赖以发展进化的技术。历史上有两种传统的远程教育:远程课堂教学和函授教学。它们具有不同的教育学特征和成本结构。然而,新一代技术即知识媒体,作为计算机技术、电子通信技术和认知科学汇同结合的产物,正在将远程教育的两大传统结合在一起。知识媒体将通过进一步发展远程教育对大学的革新作出重大贡献。     

茉莉酸对油菜(Brassica napus L.)受镉毒害的缓解作用（英文）

目的:本研究目的在于了解:(1)喷施外源茉莉酸对受到镉胁迫油菜的作用;(2)是否茉莉酸能够通过增强气体交换,从而保护受到氧化胁迫的地上部分组织的叶绿体,进而通过减少镉的吸收来维持离子平衡;(3)是否通过喷施茉莉酸来对具有减缓镉毒害效应的抗氧化酶的活性进行调节。创新点:茉莉酸能够调节响应胁迫的抗氧化酶的活性,从而通过保护叶绿体免受活性氧(ROS)伤害而提高光合产物的能力,最大限度地缓解油菜植株受到的镉毒害。方法:(1)叶片气体交换;(2)叶片光合色素分析;(3)丙二醛与抗氧化酶活性分析;(4)营养成分分析;(5)透射电镜亚细胞水平观察。结论:茉莉酸对于植物受镉毒害的缓解作用的机理在于减少叶片中镉的积累,从而减轻氧化胁迫过程中产生的ROS对于膜系统的损害程度。     

Anti-allergic effects of ethanol extracts from brown seaweeds

Ethanol extracts of brown seaweeds from Pakistan and China were isolated and compared for their antiallergenic activities.They included Sargassum tennerimum (ST) and Sargassum cervicorne (SC) from Pakistan,and Sargassum graminifolium turn (SG),Sargassum thunbergii (STH),and Laminariajaponica (LJ) from China.The ethanol extracts of these brown seaweeds were optimized at 85% (v/v) ethanol for the maximum yield of phlorotannin,an inhibitor against hyaluronidase.Total phlorotannins contained in the crude extracts were measured as 1.71% (SG),0.74% (STH),0.97% (LJ),3.30% (SC),and 5.06% (ST).The 50% inhibitory concentrations (IC50) of Pakistani SC and ST were 109.5 and 21 μg/ml,respectively,lower than those of Chinese SG,STH,and LJ (134,269,and 148 μg/ml,respectively).An antiallergic drug,disodium cromoglycate (DSCG),had an IC50=39 μg/ml,and a natural inhibitor of hyaluronidase,catechin,had an IC50=20 μg/ml.The IC50 of ST extract was found similar to that of catechin (21 vs 20 μg/ml) and lower than that of DSCG (21 vs 39 μg/ml).This suggests that ST is a potent inhibitor of hyaluronidase,indicating a promising future development of natural antiallergic medicines or functional foods.