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941.
942.
943.
This study focused on combining both the group- and individual-level analyses in studying a collaborative activity in technology-enhanced interactions in a higher education setting. The aim was to make visible, with empirical examples, the quality of the students' web-based discussions and trace the route for shared understanding. By quantifying various communicative functions, the analysis provided general knowledge on the quality and purpose of the discussion in the group and highlighted the different functional positions each student had within the group. However, only a detailed interpretative analysis of the relationships between specific thematic contents, communicative functions, and the collaborative features of the discussion, in the temporal frame, made it possible to trace and gain a deeper understanding of the true acts of collaboration. It also highlighted the individual participants' different participatory and discursive positions in the different phases of the task. Over the study, it became evident that any attempts to define a collaborative activity from either the group's or individual's perspective would only result in a partial interpretation of the collaborative enterprise.  相似文献   
944.
In our article, we explore the possibility of formulating theses about teaching as one way to use research as a basis for educational action. The theses are formulated from current educational research on teaching and learning in higher education. We also explore the potential for action and the consequences derived from the theses. With our theses, we criticise less complex ways of using research for educational purposes. Through theses we can suggest directions for action without prescribing certain methods or procedures and provide answers without reducing the teachers' possibilities for choice or diminishing their responsibility for their actions. Our exploration is an invitation to a collaborative exploration of theses on teaching and learning in order to broaden and deepen our shared basis for educational action.  相似文献   
945.
Mechanical properties of wood at different length scales of its hierarchical structure are governed by structural and compositional properties on smaller length scales. This opens up the possibility to use microstructural data for estimating mechanical properties, which are difficult to assess by conventional, destructive testing but are nevertheless of high relevance for conservation practice. Herein, we investigate such microstructure-mechanics relationships for a particular example, namely the load bearing archaeological oak of the Oseberg Viking ship, displayed at the Viking Ship Museum in Oslo, Norway. In order to identify the effects of degradation on the mechanical behavior and their relations to the microstructure, recent oak specimens of different geographical origin (Norway and Austria) are investigated as well. Wood exhibits a cellular structure. Its cell walls are composed of an amorphous polymer matrix consisting of lignin and hemicelluloses and embedded, stiff cellulose fibers. At the cell level, experimental studies comprised microscopic investigations of the cellular structure, chemical analyses of the composition of the cell walls, as well as nanoindentation tests on single cell walls. The same samples were also analyzed on the macroscopic level, where additionally mass density and annual ring data were measured together with ultrasonic stiffnesses. The chemical data clearly indicate deterioration in the archaeological oak, affecting mainly hemicelluloses and amorphous cellulose. At the cell wall scale, however, this does not necessarily lead to a weaker material behavior. The nanoindentation modulus, as a measure of the cell wall stiffness, was found to even increase. This is counterintuitive to our understanding of the effects of chemical degradation. It might be due to possible modification of lignin in the Oseberg oak, and thus have a stronger effect on the indentation modulus than the concurrent weakening of the interfaces between the load-carrying cellulose fibers and the connecting cell wall matrix when analyzing wood at the microscopic level. A similar effect is also observed for the transversal stiffness of macroscopic samples, which increases. In tension-dominated loading modes, however, the degradation of the interfaces is the dominant effect, resulting for example in a considerable reduction of the macroscopic stiffness in longitudinal direction. This underlines the utmost relevance of the loading condition on the remaining load-carrying capacity of degraded wood. On the macroscale, effects of the geographical origin (i.e. growth conditions) on ring characteristics of the oak tissues override the effects of degradation on the mechanical behavior. They have to be carefully extracted in order to come up with conclusions on the effect of degradation from macroscopic test results. The identified microstructure-mechanics relationships provide the basis for–in further research steps–building mathematical models describing the relations between microstructural characteristics and macroscopic mechanical properties and, thereon, for structural analyses of historical wooden objects.  相似文献   
946.
Abstract

The Allied occupation of Istanbul is a little-known historical event outside of Turkey and the Middle East. European powers occupied Istanbul between 1918 and 1923 to enforce the partition of the Ottoman Empire after WWI in the construction of the Modern Middle East. Almost 100 Turkish novels that address occupied Istanbul have appeared over the last ninety years, beginning even before Allied armies left Istanbul in 1923. Turkey's present Middle Eastern re-emergence and post-Kemalist reassessment of secular modernity has also led writers and intellectuals back to the occupation of Istanbul. To examine why Turkish authors return repeatedly to the trope of occupied Istanbul, this essay surveys the first canonised novels about occupied Istanbul written during the Kemalist monoparty period (1923–50): Shirt of Flame by the exiled feminist and nationalist Halide Edib (1884–1964), Sodom and Gomorrah by the Kemalist ideologue Yakup Kadri Karaosmano?lu (1889–1974) and Outside the Scene by Turkey's first experimental, modernist author Ahmet Hamdi Tanp?nar (1902–62). As bilingual Istanbul intellectuals, all three made occupied Istanbul a central drama in their fictions. However, each represented it differently as a formative event in the construction and critique of the nation-state and of modern Turkish subject-formation.  相似文献   
947.
ABSTRACT

Background: Pedagogical models have become an established component of physical education over the past several decades. One such model, the Teaching Personal and Social Responsibility model, has gained momentum in practice and research, though little is known regarding its use in preservice teacher training. The model follows a flexible format focused on teaching life skills (e.g. leadership) that can be applied in all lived ecologies. Occupational socialization theory provides insight into the pretraining and teacher education experiences of preservice teachers that shape their understanding and practice of physical education and associated pedagogical models.

Aims: The purpose of this study was to understand the influence of a sequence of methods courses and early field experiences on U.S. preservice teachers’ understanding and implementation of the teaching personal and social responsibility model with youth from a community affected by poverty.

Method: This study took on a phenomenological and social constructivist approach. Ten preservice teachers (9 males, 1 female) took part in the study. The participants were an average age of 22.10 years old (SD?=?4.38) and seven identified as White and three as Black. Each participant was enrolled in methods and early field experience coursework that provided scaffolded training in primary education in a community affected by poverty. Preservice teachers team-taught groups of 10–15 children twice a week along with one day committed to on-campus reflection. Data collection included autobiographical essays, critical incident reports, reflective journals, non-participatory observations and field notes, and semi-structured interviews. Data were analyzed deductively through the lens of occupational socialization theory, and inductively as theory divergent trends were sought. Open and axial coding was completed with member checking throughout, resulting in a final set of themes and subthemes.

Findings: The preservice teachers initially struggled to connect with their students due to conflicting backgrounds, but the teaching personal and social responsibility model guided the relationship-building process. As the model was continuously utilized, more empathy and care were shown towards the children. Preservice teachers felt there was a lack of progression in positive behaviors but were able to empower youth and felt that the model was culturally relevant. Overtime, the students began to appreciate the affective domain despite the challenge of working in a community affected by poverty through frustration towards the larger system limiting any potential progress was present.

Conclusions: Subjective theories transitioned to include relationship building and life skills learning, likely because of the extended field experience and faculty support. The preservice teachers desire to connect with and teach the students well displays the connection between models-based practice and positive relationships. Preservice teachers’ knowledge of their students was limited as it was based on secondhand knowledge of youth, teacher educators, and school staff. Evidence indicates some cultural responsiveness development though there were also elements of a deficit model due to white privilege and class differences. Further work explicitly integrating a culturally relevant approach and social justice in teacher education programming should occur.  相似文献   
948.
ABSTRACT

Previously, heavy use of biocides for the treatment of objects made of organic materials in museum collections (e.g. ethnographic, historical collections) was very common. Now suitable decontamination methods/technologies are being sought. A decontamination treatment by li-CO2 was optimized that considered the specific requirements of museum objects. The treatment was tested on model materials artificially contaminated with biocide solutions containing dichlorodiphenyltrichloroethane (DDT), pentachlorophenol (PCP), lindane, and permethrin or cypermethrin. High decontamination was achieved for DDT, lindane, PCP, and permethrin on artificially biocide loaded wool and wood model materials. Optimal process parameter settings for li-CO2 decontamination include a single 30?min cycle for woolen materials and three sequential 30?min cycles each for wood. These methods allow a reduction of at least 90% of all biocides for wool and between 70% and 85% for wood. Decontamination of the latter was more effective for less polar biocides as DDT and permethrin. Despite a significant improvement in decontamination for wood using co-solvents such as acetone, ethanol, and methyl tertiary-butyl ether (MTBE), their use is not recommended due to the increased risk of damage to the objects, in particular if a surface coating is present.  相似文献   
949.
Martin to Brown     
The rise of the modern Black Lives Matter movement can be traced back to two key events, the 2012 death of Trayvon Martin and the 2014 death of Michael Brown. Research routinely showed that mainstream media’s narrative choices marginalize and delegitimize protesters and their causes, a pattern known as the protest paradigm. This study provides a longitudinal examination of how the same mainstream media system varied in their coverage of similar events and the degree to which journalists challenged the predicted paradigms conceptualized in other academic work. A content analysis of national newspaper coverage revealed that news before the judicial rulings focused on protesters’ tactics (violence versus peaceful) and changed to the realm of ideas (grievances and demands) after the assailants were considered not guilty of wrongdoing. No progression was found in legitimizing coverage of protests between the two cases.  相似文献   
950.
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