The use of hydroxyapatite as a new inorganic consolidant for damaged carbonate stones

The feasibility and the effectiveness of using hydroxyapatite (HAP) formed by reacting limestone with a solution of diammonium hydrogen phosphate (DAP) in mild conditions, as a consolidant for carbonate stones were investigated. Firstly, a novel method for predamaging limestone was developed. Then, the effects of DAP solution concentration and reaction duration were evaluated to define the best treatment conditions, and the strengthening effect was evaluated on artificially damaged Indiana Limestone samples. Treated samples exhibit a significant increase in the dynamic elastic modulus and tensile strength, which is attributed to microcrack reduction and pore filling consequent to formation of calcium phosphate phases at grain boundaries, as assessed by SEM/EDS and ESEM/EBSD. Consequent to a slight reduction of coarser pores, as revealed by MIP, the sorptivity of treated samples is only slightly reduced, so that water and water vapor exchanges with the environment are not significantly blocked.     

Identifying patterns of students' performance on simulated inquiry tasks using PISA 2015 log-file data

Previous research has demonstrated the potential of examining log-file data from computer-based assessments to understand student interactions with complex inquiry tasks. Rather than solely providing information about what has been achieved or the accuracy of student responses (product data), students' log files offer additional insights into how the responses were produced (process data). In this study, we examined students' log files to detect patterns of students' interactions with computer-based assessment and to determine whether unique characteristics of these interactions emerge as distinct profiles of inquiry performance. Knowledge about the characteristics of these profiles can shed light on why some students are more successful at solving simulated inquiry tasks than others and how to support student understanding of scientific inquiry through computer-based environments. We analyzed the Norwegian PISA 2015 log-file data, science performance as well as background questionnaire (N = 1,222 students) by focusing on two inquiry tasks, which required scientific reasoning skills: coordinating the effects of multiple variables and coordinating theory and evidence. Using a mixture modeling approach, we identified three distinct profiles of students' inquiry performance: strategic, emergent, and disengaged. These profiles revealed different characteristics of students' exploration behavior, inquiry strategy, time-on-task, and item accuracy. Further analyses showed that students' assignment to these profiles varied according to their demographic characteristics (gender, socio-economic status, and language at home), attitudes (enjoyment in science, self-efficacy, and test anxiety), and science achievement. Although students' profiles on the two inquiry tasks were significantly related, we also found some variations in the proportion of students' transitions between profiles. Our study contributes to understanding how students interact with complex simulated inquiry tasks and showcases how log-file data from PISA 2015 can aid this understanding.     

Kulturelle Bildung an den Schulen in Deutschland

Previous research findings suggest that school types differ in terms of their extracurricular art-aesthetic offers and that at “Gymnasien” (grammar schools) and “Comprehensive Schools” conditions for art-aesthetic education are particularly favorable. Furthermore, at all-day schools they seem to be more favorable than at other schools. To see whether these findings can be confirmed and differences between school types can be found even after controlling for relevant school characteristics, a nationwide representative survey of school leaders at state schools was analyzed. Three dimensions of art-aesthetic education were examined: extracurricular art-aesthetic offers, cooperation with out-of-school cultural institutions and, finally, school profiles. The results allow for a differentiation and complementation of former findings concerning the specific conditions at different school types regarding the advancement of art-aesthetic experiences, because characteristics such as all-day-school organization, school size or resources were considered.     

Enhancing pre-service teachers’ technological pedagogical content knowledge (TPACK): a mixed-method study

Educational technology research and development - The main aim of this two-step mixed-method study was to explore the effectiveness of the strategies used to prepare pre-service teachers for...     

Noticing Children’s Learning Processes – Teachers Jointly Reflect on Their Own Classroom Interaction for Improving Mathematics Teaching

One could focus on many different aspects of improving the quality of mathematics teaching. For a better understanding of children’s mathematical learning processes or teaching and learning in general, reflection on and analysis of concrete classroom situations are of major importance. On the basis of experiences gained in a collaborative research project with elementary school teachers, several ideas about a professional reflection on one’s own instruction activities are explained. The paper focuses on joint reflection between teachers and researchers on the participating teacher’s own classroom interaction by means of concrete examples. It becomes clear that changes of one’s own interaction behavior will take place only in the long-term. Nevertheless such a joint professional reflection should be an essential component of teachers’ professional knowledge in a natural way. An erratum to this article can be found at     

Stereotype change following exposure to counter‐stereotypical media heroes

During his 1966–69 tenure as director of research for the Lutheran Council in the U.S.A., Ronald L. Johnstone helped plan and conduct the research reported here which is based on a sizable national sample. In the article, he constructs a profile of the typical religious radio program listener. Dr. Johnstone earned the Ph.D. from the University of Michigan in 1963 and is now associate professor of sociology at Central Michigan University in Mt. Pleasant.     

The Evolution of Free-Lance Music Composition, 1650–1900

Using qualitative histories and coded data on 645 composers born between 1650and 1849, this article traces the evolution of free-lance activity by musiccomposers over the course of two centuries. Contrary to widely advancedsuppositions, many composers were pursuing free-lance composition as the 17thcentury ended, although more for opera than instrumental music writing. Fromthat time on, free-lance composition expanded steadily, replacing employmentby the church and the nobility. A growing number of composers also acted asimpresarios in organizing their own opera or concert performances. Composersearned their bread in many other ways too. There were clear rising trends intheir employment as private orchestra directors and conservatory professors.