Demonstrating chemistry phenomena and back-and-forth thinking between phenomena, concepts, and various representations and visualizations

Johnstone's (1993, 2009)“chemistry triangle” comprises three levels of processing to describe and explain chemical phenomena: Macro-, Micro-, and Symbolic-level. Experienced chemists can easily switch between the different levels, but learners often struggle to do so. Pupils have to learn to think back-and-forth between phenomena and theory, and switch between the three levels of description and explanation of phenomena. In this article we describe the relationship between hands-on and minds-on approaches to learning chemistry concepts through teacher demonstrations. We provide guidance and a strategy to facilitate smooth switching between the different levels. In Section 1 we introduce" meaning-making" through Thinking Back-and-Forth (TBF) between the Domain of Observables (phenomena, objects and observations) and the Domain of Ideas (concepts, theories and models). In Section 2, the back-and-forth thinking model (Abrahams & Millar, 2008; Spaan et al, 2023) is expanded to incorporate the various levels of processing as outlined in Johnstone's" Chemistry Triangle"(1993, 2009). Finally, in Section 3, we conclude with some strategies for visualizing the micro level. To illustrate the back-and-forth thinking between phenomena, concepts, and visualizations we used the example of the reaction between a copper (II) nitrate solution and iron nail/steel wool

The Leiden Ranking 2011/2012: Data collection, indicators, and interpretation

The Leiden Ranking 2011/2012 is a ranking of universities based on bibliometric indicators of publication output, citation impact, and scientific collaboration. The ranking includes 500 major universities from 41 different countries. This paper provides an extensive discussion of the Leiden Ranking 2011/2012. The ranking is compared with other global university rankings, in particular the Academic Ranking of World Universities (commonly known as the Shanghai Ranking) and the Times Higher Education World University Rankings. Also, a detailed description is offered of the data collection methodology of the Leiden Ranking 2011/2012 and of the indicators used in the ranking. Various innovations in the Leiden Ranking 2011/2012 are presented. These innovations include (1) an indicator based on counting a university's highly cited publications, (2) indicators based on fractional rather than full counting of collaborative publications, (3) the possibility of excluding non-English language publications, and (4) the use of stability intervals. Finally, some comments are made on the interpretation of the ranking, and a number of limitations of the ranking are pointed out

Open Data Within governmental Organisations: Effects, Benefits and Challenges of the Implementation Process

This article describes the growth of open government, open data and the means for transparency and accountability but aims to reflect on the bottlenecks and actual practicallity of opening data to the public domain by two governmental bodies. The Municiaplity of The Hague and The Province of South-Holland of The Netherlands are part of 2 research programmes called ‘Government of the Future’, which main goals are to explore and establish knowledge on societal innovation by new applications and possibilities of long term effects of ICT’s in the public sector. Part of these programmes are themes as transparecny and open data, which are  viewed form the somewhat pragmatic and operational side of its applicability. The paper shows the development within the governmental bodies and captivates the ‘readiness’ for open data

The Grizzly, April 15, 1988

Greek Week\u27s Coming! • Sorority Songfest Sunday • Letters: Visser to Goofley: Kiss Dirt!; Code: Honor; Billing Miffs Student; Professor Nagy Responds to Tiryak Forum; Red Cross Congratulates UC Donators • Mid East Forum Scheduled • Take Women\u27s Studies! • 1988-89 RAs Announced • Men\u27s Track Races to 5-0 • LAX Hopes to Lift Level of Play Against West Chester • Women\u27s Outdoor Places Fourth • Baseball Hopes to Turn Season Around vs. Widener • Race-rafters Rollick • Underclassmen Pitching Power Carrying Softballers • Hallinger Takes Third • Strong Sailing for U.C. • The Grizzly\u27s Senior Sports Spotlight Salutes Kris Carr • Women Students Rule • Tommy Conwell in Concert Rumbles Ursinus • Portrait of an Artist • STAR Ambassadors Shinehttps://digitalcommons.ursinus.edu/grizzlynews/1211/thumbnail.jp

Clostridium difficile Ribotype 027, Toxinotype III, the Netherlands

Outbreaks due to Clostridium difficile polymerase chain reaction (PCR) ribotype 027, toxinotype III, were detected in 7 hospitals in the Netherlands from April 2005 to February 2006. One hospital experienced at the same time a second outbreak due to a toxin A–negative C. difficile PCR ribotype 017 toxinotype VIII strain. The outbreaks are difficult to control

Development and psychometric evaluation of the Decision Tool Anxiety Disorders, OCD and PTSD (DTAOP):Facilitating the early detection of patients in need of highly specialized care

Background: Early identification of patients with an anxiety disorder, obsessive-compulsive disorder (OCD), or post-traumatic stress disorder (PTSD) in need of highly specialized care could facilitate the selection of the optimal initial treatment in these patients. This paper describes the development and psychometric evaluation of the Decision Tool Anxiety Disorders, OCD and PTSD (DTAOP), which aims to aid clinicians in the early identification of patients with an anxiety disorder, OCD, or PTSD in need of highly specialized mental healthcare. Methods: A systematic literature review and a concept mapping procedure were carried out to inform the development of the DTAOP. To evaluate the psychometric properties of the DTAOP, a cross-sectional study in 454 patients with a DSM-IV-TR anxiety disorder was carried out. Feasibility was evaluated by the completion time and the content clarity of the DTAOP. Inter-rater reliability was assessed in a subsample of 87 patients. Spearman’s rank correlation coefficients between the DTAOP and EuroQol five-dimensional questionnaire (EQ-5D-5L) scores were computed to examine the convergent validity. Criterion validity was assessed against independent clinical judgments made by clinicians. Results: The average time required to complete the eight-item DTAOP was 4.6 min and the total DTAOP was evaluated as clear in the majority (93%) of the evaluations. Krippendorff’s alpha estimates ranged from 0.427 to 0.839. Based on the qualitative feedback, item wording and instructions were improved. As hypothesized, the DTAOP correlated negatively with EQ-5D-5L scores. The area under the curve was 0.826 and the cut-off score of >= 4 optimized sensitivity (70%) and specificity (71%). Conclusions: The DTAOP demonstrated excellent feasibility and good validity, but weak inter-rater reliability. Based on the qualitative feedback and reliability estimates, revisions and refinements of the wording and instructions were made, resulting in the final version of the DTAOP