Collaborative knowledge-making in the everyday practice of youth suicide prevention education

The development and implementation of a new school‐based suicide prevention education programme in one secondary school in Vancouver, British Columbia, recently provided us with an opportunity to conduct an in‐depth, qualitative case study. The purpose of our study was to deepen our understanding of how school‐based suicide prevention education programmes like this one get planned and enacted in particular, local settings. We argue that the narrow range of methodologies that have traditionally been deployed to study school‐based youth suicide prevention education programmes have hindered our ability to see the complexities and potentialities of this work. Through the presentation of a sub‐set of findings, we aim to show the possibilities for fresh thinking and contextualized understandings that a qualitative case study, informed by a constructionist methodology, invites.     

Pre-service teachers' use of problem-solving in primary science

The use of problem-solving in science instruction implies a change in the teacher's role from dispensing content information to encouraging critical reflective thinking in the student. For problem-solving to become an integral part of the science curriculum, teachers must make it the focus of their instruction. This study investigated the extent to which pre-service primary teachers used the problem-solving approach in their science instruction. It also identified the factors affecting their efforts to teach science using this approach. The issues considered are important in whether problem-solving becomes part of the science curriculum, as teaching behaviour influences student learning outcomes. Specializations: science eeducation Specializations: educational measurement, research methodology.     

The Effects of Verbal Mediation Training on the Problem‐Solving Skills of Children with Partial Sight and Children without Visual Impairments

Thirty children with partial sight and 30 children with unimpaired sight aged between 8 and 12 years were randomly assigned to either verbal mediation or visual mediation training regimes. Participants were asked to complete four variations of the Tower of Hanoi puzzle and success on the task was judged on the basis of the number of moves and time taken to complete the puzzles. Children with visual impairments had some difficulty in adjusting to the requirements of the problem‐solving tasks. However, on the final and most difficult of the tasks (a four‐disc problem), the children with impaired sight performed very much like participants without visual impairments. The effect of verbal mediation training was superior to that of visual mediation training in the final trials of the four‐disc problem‐solving period for both children with partial sight and children without visual impairments.     

A retrospective look at replacing face‐to‐face embryology instruction with online lectures in a human anatomy course

Embryology is integrated into the Clinically Oriented Anatomy course at the Texas Tech University Health Sciences Center School of Medicine. Before 2008, the same instructor presented embryology in 13 face‐to‐face lectures distributed by organ systems throughout the course. For the 2008 and 2009 offerings of the course, a hybrid embryology instruction model with four face‐to‐face classes that supplemented online recorded lectures was used. One instructor delivered the lectures face‐to‐face in 2007 and by online videos in 2008–2009, while a second instructor provided the supplemental face‐to‐face classes in 2008–2009. The same embryology learning objectives and selected examination questions were used for each of the three years. This allowed direct comparison of learning outcomes, as measured by examination performance, for students receiving only face‐to‐face embryology instruction versus the hybrid approach. Comparison of the face‐to‐face lectures to the hybrid approach showed no difference in overall class performance on embryology questions that were used all three years. Moreover, there was no differential effect of the delivery method on the examination scores for bottom quartile students. Students completed an end‐of‐course survey to assess their opinions. They rated the two forms of delivery similarly on a six‐point Likert scale and reported that face‐to‐face lectures have the advantage of allowing them to interact with the instructor, whereas online lectures could be paused, replayed, and viewed at any time. These experiences suggest the need for well‐designed prospective studies to determine whether online lectures can be used to enhance the efficacy of embryology instruction. Anat Sci Educ 7: 234–241. © 2013 American Association of Anatomists.     

秦始皇兵马俑博物馆室内含硫颗粒物的SEM-EDX研究

本文对秦始皇兵马俑博物馆室内采集的长短期降尘、大气悬浮颗粒物和彩绘漆层进行了SEM-EDX研究，在大气悬浮颗粒、短期和长期降尘中，含硫颗粒的粒径分别为0.9～22.8μm、1.0～29.0μm和1.2～37.7μm，多为石膏与粘土或石英以内部混合的状态存在。降尘中的附着型絮状硫酸钙多于大气悬浮颗粒物中，显示降尘和大气中的二氧化硫发生了累进的化学反应。彩绘漆层表面的坑和裂隙附近观察到原位生长的硫酸钙晶体，显示漆层材料或降尘颗粒物与大气二氧化硫之间的酸化学反应，可能是彩绘漆层表面受侵蚀形成微小坑和裂隙的原因之一。     

Dependency structure language model for topic detection and tracking

In this paper, we propose a new language model, namely, a dependency structure language model, for topic detection and tracking (TDT) to compensate for weakness of unigram and bigram language models. The dependency structure language model is based on the Chow expansion theory and the dependency parse tree generated by a linguistic parser. So, long-distance dependencies can be naturally captured by the dependency structure language model. We carried out extensive experiments to verify the proposed model on topic tracking and link detection in TDT. In both cases, the dependency structure language models perform better than strong baseline approaches.