The Use of Video Demonstrations and Particulate Animation in General Chemistry

Different visualization techniques have been used for teaching chemistry concepts. Previous studies have shown that when molecular animations and video demonstrations are used, students seem to better correlate all three levels of representation: macroscopic, submicroscopic, and symbolic. This thinking process allows the students to improve their conceptual understanding and ability to create dynamic mental models. In this study, general chemistry students viewed three experiments involving dynamic fluid equilibrium in a graphic design, a video demonstration, and a molecular animation. The study investigated whether video demonstrations or particulate animations helped the students' conceptual understanding, and if the order of visualizations (video or animation first) produced any differences. Students showed improvement after each visualization. Surprisingly, there was significant improvement in responses between the first and second visualization. This work shows the importance of combining both types of visualizations, but it does not indicate a preference toward a specific order.     

Transsituational negative contrast

Rats were shifted from 32% sucrose solution in one apparatus to a 4% sucrose solution in a different apparatus, and the performance of these animals was compared to rats that received the 4% solution in both situations. Transsituational negative contrast effects were found in both consummatory and instrumental measures of behavior and, in addition, these contrast effects were found to have some elements in common with both successive and simultaneous contrast effects, but were identical to neither.     

The development of a user network as a way to re-launch an unwanted product

A common situation in product development is that of product failure and the need for re-launch. This paper presents findings regarding how one firm successfully re-launched a product through the ex-post development of a user network. The producer, Biacore, had to re-launch its biosensor product or lose a €50 million investment. The firm identified and interacted with multiple potential lead-users in order to generate new use applications. The firm benefited from the successful development of a set of new applications, innovative users, and sales. As sales of the product increased, Biacore created marketing channels as diffusion mechanisms for the encouragement of direct and indirect user-to-user interaction. These were a way to spread the costs of user support when the firm standardised how it interacted with users. Some follower-users were able to benefit from lead-users who became lead teachers; other follower-users became non-users of the product. This paper illustrates three main roles for the firm in developing a user network: creating lead-users, organising directed applications development and facilitating user-to-user interaction.     

Rethinking Our Mobility: Supporting Our Patrons Where They Live

This article describes initiatives undertaken by one academic medical library to support patrons using handheld mobile devices. These initiatives included efforts to assist patrons with installation and use of mobile information resources, educate librarians regarding content and navigation of mobile apps and websites, and leverage tools to promote the library in a mobile environment.     

Engaging students in active learning: use of a blog and audience response system

Librarians provide instruction to medical students as part of a core course in the medical school curriculum. Instruction was provided, in part, through didactic sessions covering professional-level medical information resources, PubMed search skills, psychosocial information, and evidence-based medicine. Librarians redesigned instructional sessions with the goals of increasing student engagement and minimizing the lecture format, maximizing the number of students receiving feedback on their search and evaluation skills, and permitting students to see a variety of possible responses as well as engage in peer- and self-evaluation. Librarians integrated the use of a blog and an audience response system (ARS) into the instruction to help accomplish these goals.     

Veränderungen in der sozialen und ethnischen Zusammensetzung der Schülerschaft aus demografischer Perspektive

In this paper, we examine current changes in the ethnic and social composition of the preschool and school aged population as well as the consequences these changes may have for educational participation and thus for overall educational attainment in the near future. Based on the micro-census 2008 survey, we identify groups of migrants by region of parents’ origin where children – despite low levels of parents’ education and comparatively few socioeconomic resources – have greater chances of upward educational mobility than non-migrant children. By contrast, children from less educated, nonmigrant families show a much lower tendency to be upwardly mobile, and educational choices are more closely tied to the economic and social background. Thus, our analysis provides evidence that educational background and socio-economic resources in the students’ families are of greater importance for the overall development of educational attainment in Germany than characteristics of migration and ethnicity.     

Blocking in autoshaped lever-pressing procedures with rats

Rats will approach and contact a lever whose insertion into the chamber signals response-independent food delivery. This “autoshaping” or “sign-tracking” phenomenon has recently attracted considerable attention as a platform for studying individual differences in impulsivity, drug sensitization, and other traits associated with vulnerability to drug addiction. Here, we examined two basic stimulus selection phenomena—blocking and overshadowing—in the autoshaped lever pressing of rats. Blocking and overshadowing were decidedly asymmetrical. Previously reinforced lever-extension conditioned stimuli (CSs) completely blocked conditioning to auditory cues (Exps. 1 and 2), and previously nonreinforced lever-extension CSs overshadowed conditioning to auditory cues. By contrast, conditioning to lever-extension CSs was not blocked by either auditory (Exp. 3) or lever-insertion (Exp. 4) cues, and was not overshadowed by auditory cues. Conditioning to a lever-insertion cue was somewhat overshadowed by the presence of another lever, especially in terms of food cup behavior displayed after lever withdrawal. We discuss several frameworks in which the apparent immunity of autoshaped lever pressing to blocking might be understood. Given evidence that different brain systems are engaged when different kinds of cues are paired with food delivery, it is worth considering the possibility that interactions among them in learning and performance may follow different rules. In particular, it is intriguing to speculate that the roles of simple cue–reinforcer contiguity, as well as of individual and aggregate reinforcer prediction errors, may differ across stimulus classes.