动物的魔力

虽然器官移植在科学上还存在极大的障碍 ,但是将动物的器官用在人体上的器官移植被许多科学家认为是唯一的长期解决全球性人类的器官匮乏的办法 .玛格丽特·西蒙斯正在关注这方面的最新发展     

The Impact of Scaffolding and Student Achievement Levels in a Problem-based Learning Environment

This study examined how scaffolds and student achievement levels influence inquiry and performance in a problem-based learning environment. The scaffolds were embedded within a hypermedia program that placed students at the center of a problem in which they were trying to become the youngest person to fly around the world in a balloon. One-hundred and eleven seventh grade students enrolled in a science and technology course worked in collaborative groups for a duration of 3 weeks to complete a project that included designing a balloon and a travel plan. Student groups used one of three problem-based, hypermedia programs: (1) a no scaffolding condition that did not provide access to scaffolds, (2) a scaffolding optional condition that provided access to scaffolds, but gave students the choice of whether or not to use them, and (3) a scaffolding required condition required students to complete all available scaffolds. Results revealed that students in the scaffolding optional and scaffolding required conditions performed significantly better than students in the no scaffolding condition on one of the two components of the group project. Results also showed that student achievement levels were significantly related to individual posttest scores; higher-achieving students scored better on the posttest than lower-achieving students. In addition, analyses of group notebooks confirmed qualitative differences between students in the various conditions. Specifically, those in the scaffolding required condition produced more highly organized project notebooks containing a higher percentage of entries directly relevant to the problem. These findings suggest that scaffolds may enhance inquiry and performance, especially when students are required to access and use them.     

Observational,physiological, and self-report measures of children's anger: relations to reactive versus proactive aggression

The goal of this study was to examine the relations of reactive versus proactive aggression to children's anger, as assessed using observational, physiological, and self-report measures. Anger was hypothesized to be related to reactive aggression, but not to proactive aggression. Children (N = 272 second-grade boys and girls) participated in a procedure in which they lost a board game and prize to a confederate who cheated. Skin conductance reactivity and heart rate reactivity were measured throughout the procedure. Following the interaction, children viewed a videotape of the game and self-reported on their level of anger after each turn of the game. Observational coding of children's angry facial expressions and angry nonverbal behaviors was conducted. Reactive aggression, but not proactive aggression, was positively related to skin conductance reactivity and angry nonverbal behaviors, both at an aggregated level and in terms of rate of increase over the time span of the game.     

Explaining effects and side effects of school inspections: a path analysis

There are large differences between schools with regard to how they are affected by a school inspection. This study provides quantitative evidence about the extent to which perceived effects and side effects of an inspection are related to the inspection’s judgement on the school, to features of the inspection, and to school features. This study draws on quantitative data collected from 2,202 teachers in Flemish primary and secondary schools that had recently been inspected. Using path analysis, it investigates the existence and strength of relationships between the perceived effects and side effects of inspection, on the one hand, and the perceived inspection quality, the perceived school’s policy-making capacities, and the inspection judgement, on the other hand. The analysis reveals that most effects and several side effects are predominantly explained by the perceived inspection quality. Emotional side effects during inspection are best predicted by the school’s policy-making capacities.     

Understanding students' errors with Prolog unification

One of the mechanisms that a student of Prolog must learn to understand and to use is unification. Initially students have only a partial understanding of unification and therefore they are not able to fully understand the execution of a program. This paper shows that a considerable part of the errors that students make can be explained by an impaired version of the correct algorithm. The changes from the correct algorithm to the false algorithms can be justified by a psychologically plausible mechanism.     

Environmental education excursions and proximity to urban green space – densification in a ‘compact city’

The value of urban green space for environmental education fieldwork is empirically investigated in a study among all secondary schools in Amsterdam. The article describes how the proximity of schools to green spaces emerges as a new factor in the ‘sustainable city’ and the ‘compact city’ debate. For fieldwork excursions proximity to green spaces is crucial for establishing a pattern of outdoor environmental education. Once established, it shapes teachers’ attitudes on excursions. A linear structural path analysis reveals how this in turn results in more fieldwork excursions to other destinations. Interviews with teachers show how this can be interpreted mainly as a result from iterative positive experiences with excursions close to the school, which are triggered by the availability of nearby green space. Remarkably, beside the effects of green spaces for well-being and health, the significance of green space for environmental education of children remained under-investigated. This argument came prominently to the fore in a case of urban densification within the framework of compact city policies. In the dispute about the elimination of green space, citizens claimed a high educational value would vanish, but they felt this value was not recognized in the decision-making process.     

“Trust Me,I’m a Scientist”

Science & Education - Modern democratic societies tend to appeal to the authority of science when dealing with important challenges and solving their problems. Nevertheless, distrust in science...     

Schools in the making: mapping digital spaces of evidence

In this article, the focus is on educational governing in the making. Drawing on conceptual underpinnings of socio-technical approaches, this implies an interest both on the way in which a sound knowledge base for policy measures is created, as on the distribution of that knowledge through publically available instruments. Governing by evidence only is possible when it relies on concrete instruments, such as feedback reports, publically consultable audits and examples of good practice. Since knowledge-related practices increasingly make use of online tools where knowledge is accessible for each and all, three websites are analysed in a particular way to describe the making of evidence. First, considered as active devices, the websites are analysed as essential components of the governing by evidence: by publishing specific data and information in a particular way, they come to constitute what comes to count as evidence and the way in which it comes to count. By addressing their visitors in a particular way, moreover, they constitute for whom it comes to count as evidence. As such, we argue, it becomes visible that digital spaces of evidence actually make schools real, and, at once, that there are different modes for schools to exist.