玻璃和熔体包裹体中水含量的拉曼光谱定量测定方面的进展评述

This paper is focused on the progress in the determination of water in glasses and melt inclusions with Raman spectroscopy. Using the presented ＂Comparator Technique＂ the water content of a sample is determined by siruple comparison with a known standard. A calibration curve is not necessary. Furthermore, with this technique the water concentration in silicate melt inclusions can be determined without exposing the inclusions for measurements. This is very important for extremely water-rich melt inclusions, which would loose H2O on exposure.     

The CAEB: An instrument for measuring connotative aspects of epistemological beliefs

This article presents a semantic differential called Connotative Aspects of Epistemological Beliefs (CAEB) developed to assess university students' epistemological beliefs with adjective pairs such as dynamic–static and objective–subjective. After discussing the theoretical background, data are reported from two validation studies. The aim of the studies was to examine the emerging factor structure in different domains and to test whether CAEB can be used to measure domain-dependent differences in students' beliefs. Results showed a reasonable two-factor solution. The results further confirmed that the CAEB could measure differences in students' epistemological beliefs about knowledge in different domains of natural sciences like genetics, physics and plant identification.     

Building on student mathematical thinking in whole-class discourse: exploring teachers’ in-the-moment decision-making,interpretation, and underlying conceptions

Often, mathematics teachers do not incorporate whole-class discourse of students’ various ideas and solution methods into their teaching practice. Particularly complex is the in-the-moment decision-making that is necessary to build on students’ thinking and develop their collective construction of mathematics. This study explores the decision-making patterns of five experienced Dutch mathematics teachers during their novice attempts at orchestrating whole-class discourse concerning students’ various solution methods. Our goal has been to unpack the complexity of their in-the-moment decision-making during whole-class discourse through lesson observations and stimulated recall interviews. We investigated teacher decision-making adopting a model that combines two perspectives, namely (1) we explored student-teacher interaction with regard to building on student thinking and (2) we explored how the teachers based decisions during such interaction upon their own personal conceptions and interpretation of student thinking. During these novice attempts at orchestrating whole-class discourse, the teachers created many situations for students to articulate their thinking. We found that at certain instances, teachers’ in-the-moment decision-making resulted in opportunities to build on student thinking that were not completely seized. During such instances, the teachers’ decision-making was shaped by the teachers’ own conceptions of the relevant mathematics and by teacher conceptions that centered around student understanding and mathematical goals. Our findings suggest that teachers might be supported in their novice attempts at whole-class discourse by explicit discussion of the mathematics and of their conceptions with regard to student understanding and mathematical goals.

     

Making sense of student mathematical thinking: the role of teacher mathematical thinking

Educational Studies in Mathematics - In mathematical whole-class discussions, teachers can build on various student ideas and develop these ideas toward mathematical goals. This requires teachers...     

The Public's Bounded Understanding of Science

This introduction to the special issue Understanding the Public Understanding of Science: Psychological Approaches discusses some of the challenges people face in understanding science. We focus on people's inevitably bounded understanding of science topics; research must address how people make decisions in science domains such as health and medicine without having the deep and extensive understanding that is characteristic of domain experts. The articles reflect two broad streams of research on the public understanding of science—the learning orientation that seeks to improve understanding through better instruction and the communications orientation that focuses on attitudes about science and trust in scientists. Challenges to understanding science include determining the relevance of information, the tentativeness of scientific truth, distinguishing between scientific and nonscientific issues, and determining what is true and what is false. Studying the public understanding of science can potentially contribute to psychological theories of thinking and reasoning in modern societies.     

Interactive development of subject matter in the mathematics classroom

There are considerable differences among mathematics teachers with regard to the quatlity of their way of developing mathematical knowledge in the classroom. Such differences are analysed. To develop mathematical meaning requires both a consistent presentation of the mathematical symbols and of the referential meaning of these symbols with respect to the given task. On the basis of this conception we assume that the quality of teaching will differ according to how teachers cope with the relation between these two sides of meaning. From a sample of 26 teachers, an expert teacher and a non-expert teacher were selected by means of classroom observation with scales of instructional quality variables. For each of these two teachers, two lessons introducing probability (sixth grade) are analysed. For this purpose, teacher and student contributions are coded. For the expert teacher, graphic visualizations of the development of mathematical concepts across time show soft transitions between the different aspects of mathematical meaning. These transitions are made possible by a consistent explication of the relation between formal symbols and the given mathematical task. In the case of the other teacher, explication of the relationship between the object side and the symbol side of mathematical meaning is much rarer, and there are sudden switches from one aspect of meaning to another. Further differences concern the handling of student contributions.We gratefully acknowledge the help of Wolfgang Barz, Regina Dietrich and Claudia Krüger with recording, transcribing or coding lessons. For their comments on draft versions of the paper the authors thank Deborah Ball, Jere Brophy, Willibald Dörfler, Alexander Gruza and two anonymous reviewers.     

The seduction of easiness: How science depictions influence laypeople’s reliance on their own evaluation of scientific information

The present research investigated whether laypeople are inclined to rely on their own evaluations of the acceptability of scientific claims despite their knowledge limitations. Specifically, we tested whether laypeople are more prone to discount their actual dependence on expert knowledge when they are presented with simplified science texts. In two experiments, participants read scientific arguments that varied in comprehensibility and type of argument support and therefore in apparent easiness. We assessed participants’ inclination to rely on their own evaluation rather than deferring to expert advice when judging argument persuasiveness. The results showed that laypeople were more strongly persuaded by apparently easy arguments than by difficult ones. Furthermore, they were more confident in their own evaluation of the information and less inclined to turn to an expert for decision-making support after reading easy compared to difficult arguments.