Snippets of physics

Thomas precession is a curious effect in special relativity which is purely kinematical in origin and illustrates some important features of the Lorentz transformation. It also has a beautiful geometric interpretation. We will explore these in this and the next installment. T Padmanabhan works at IUCAA, Pune and is interested in all areas of theoretical physics, especially those which have something to do with gravity.     

Cognitive and linguistic constraints on phoneme isolation in Dutch kindergartners

This study investigated whether task instructions affect sound-isolation performance. The effects of phoneme class and phoneme position were also assessed. Two hundred Dutch kindergartners were presented with a free-sound-isolation task and its constrained counterparts: an initial-, a middle-, and a final-sound-isolation task. All tasks contained 17 CVC words. Children's performance on the free-sound-isolation task was better than on the constrained tasks. On all four tasks, children made fewer errors in isolating the initial phoneme than the final phoneme. Isolating the middle phoneme proved to be the most demanding. The effect of phoneme class depended on the type of task and on phoneme position. Findings were placed against the background of sonority and word-final phoneme vocalization in Dutch.     

Snippets of physics

The Foucault pendulum is an elegant device that demonstrates the rotation of the Earth. After describing it, we will elaborate on an interesting geometrical relationship between the dynamics of the Foucault pendulum and Thomas precession discussed in the last installment¹. This will help us to understand both phenomena better. T Padmanabhan works at IUCAA, Pune and is interested in all areas of theoretical physics, especially those which have something to do with gravity.     

Education for Labour in Czechoslovakia: the shifting sands of responsibility

Vocational training in secondary schools is currently coming under close scrutiny in Czechoslovakia, and every secondary school is now charged with providing at least a measure of vocational training. At a time when vocational training in British secondary education is being given a much higher profile than ever before, there may be lessons to learn from Eastern European experience. It is the purpose of this article to describe the Czechoslovak system of vocational training at secondary level, to discern some of the problems which it faces, and to identify trends in vocationalism in Czechoslovakia for the 1990s.     

Exploring the fluctuation of motivation and use of self-regulatory processes during learning with hypermedia

We collected think-aloud, pre-test, post-test, and motivation data from 43 undergraduates to examine the impact of conceptual scaffolds on the fluctuation of certain motivation constructs and use of self-regulatory processes during learning with hypermedia. Participants were randomly assigned to either the No Scaffolding (NS) or Conceptual Scaffolding (CS) condition. During the experimental session, each participant individually completed a pre-test on the circulatory system, a pre-task motivation questionnaire, one 30-min hypermedia learning task during which they learned about the circulatory system, a motivation questionnaire at three regular intervals during this learning task, a post-test on the circulatory system, and a post-task motivation questionnaire. Results indicated that while participants in both conditions gained declarative knowledge, participants who received conceptual scaffolds during learning demonstrated deeper understanding of the circulatory system on the post-test. In terms of self-regulatory processes, the results indicated that participants in the CS condition used significantly more planning processes during learning than participants in the NS condition. Additionally, participants in both conditions significantly decreased their use of strategies as they progressed through the learning task. Regarding motivation while learning with hypermedia, results indicated that participants in both conditions reported significantly increased levels of interest as they progressed through the learning task. Furthermore, participants in the CS condition reported the task as being easier and putting forth less effort than participants in the NS condition.

The representation and attainment of students with dyslexia in UK higher education

Using a database of allstudents in higher education in the UK in1995–1996, students with dyslexia and those withno reported disability were compared in termsof demographic properties, programmes of studyand academic attainment. Students with dyslexiaconstituted 0.42% of all students resident inthe UK. Their representation varied with age,gender, ethnicity and entrance qualificationsand with their level, mode and subject ofstudy. Students with dyslexia were more likelyto withdraw during their first year of studyand were less likely to complete theirprogrammes of study, although with appropriatesupport the completion rate of students withdyslexia can match that of students with nodisabilities. In addition, students withdyslexia who completed first-degree programmestended to gain a poorer class of honours thanstudents with no reported disability, but 40%obtained first-class or upper second-classhonours. In short, dyslexia may havedeleterious consequences for progression,completion and achievement in higher education,but it is by no means incompatible with a highlevel of success, given appropriate commitmenton the part of the students and appropriateresources on the part of their institution.     

网络课堂中非生理性别与生理性别对人际冲突的影响(英文)

本研究探讨了性别对网络课堂中学生间冲突程度的影响。研究者首先检查了文化和冲突间的关系,并且对性别和冲突间的关联做了文献分析,接着具体探索了生理和非生理性别（sex,gender）、网络学习经验（所上网络课程的多少）,和冲突在网络学习环境中的关联。虽然研究男女性别和冲突的文章有很多,但研究更深一步探求抽象性别（即gender,非生理性别）对冲突程度和态度的影响。研究中采用了专门研究性别和冲突的问卷调查工具。     

Comparing Automatic and Manual Measures of Parent–Infant Conversational Turns: A Word of Caution

The Language ENvironment Analysis system (LENA) records children’s language environment and provides an automatic estimate of adult–child conversational turn count (CTC). The present study compares LENA’s CTC estimate to manually coded CTC on a sample of 70 English-speaking infants recorded longitudinally at 6, 10, 14, 18, and 24 months of age. At each age, LENA’s CTC was significantly higher than manually coded CTC (all ps < .001, Cohen’s ds: 0.9–2.05), with the largest discrepancies between the two methods observed at younger ages. The Limits of Agreement Analyses confirm wide disagreements between the two methods, highlighting potential problems with automatic measurement of parent–infant verbal interaction. These findings suggest that future studies should validate LENA’s CTC estimates with manual coding.