Teachers’ Disciplinary Boundedness in the Implementation of Integrated Computational Modeling in Physics

This study explored teachers’ conceptualizations of integrated computational modeling in secondary physics by exposing twelve experienced physics teachers to programming and then analyzing interview responses. Responses revealed that teachers fell along a spectrum of disciplinary boundary–stretching mentalities. This paper presents a preliminary conceptual framework for exploring both horizontal (interdisciplinary) and vertical (intradisciplinary) boundary stretching, as well as for identifying bounded mentalities as teachers consider integration. Horizontal boundary stretchers envisioned opportunities to use computational modeling to shift their curriculum or pedagogical approaches in physics to help students enhance skills underlying multiple fields, while vertical boundary stretchers considered how computing might allow students to explore physics concepts more deeply. Teachers with more boundary-stretching indicators at the outset of an integrated curriculum development workshop were more likely to persist in the implementation of computational modeling–integrated materials in their physics classrooms than those who expressed more bounded thinking. These findings emphasize the importance of considering teachers’ perceptions about how their own science discipline is connected to similar fields and provide implications about how to identify potential adopters of innovative teaching approaches.

Convection in a mushy layer along a vertical heated wall

Motivated by the mushy zones of sea ice, volcanoes and icy moons of the outer solar system, we perform a theoretical and numerical study of boundary-layer convection along a vertical heated wall in a bounded ideal mushy region. The mush is comprised of a porous and reactive binary alloy with a mixture of saline liquid in a solid matrix, and is studied in the near-eutectic approximation. Here, we demonstrate the existence of four regions and study their behaviour asymptotically. Starting from the bottom of the wall, the four regions are (i) an isotropic corner region; (ii) a buoyancy dominated vertical boundary layer; (iii) an isotropic connection region; and (iv) a horizontal boundary layer at the top boundary with strong gradients of pressure and buoyancy. Scalings from numerical simulations are consistent with the theoretical predictions. Close to the heated wall, the convection in the mushy layer is similar to a rising buoyant plume abruptly stopped at the top, leading to increased pressure and temperature in the upper region, whose impact is discussed as an efficient melting mechanism.

Replicable Rooms and Boundary Shrinkable Skyscrapers

‘Replicable Rooms and Boundary Shrinkable Skyscrapers’ points out precisely which properties of skyscrapers are required in the remainder of the proof of the disc embedding theorem. To achieve this, it introduces an abstraction of towers, known as buildings. The required properties for a generalized skyscraper include boundary shrinkability and replicability. The former allows the conclusion that the vertical boundary of a generalized skyscraper is a solid torus. Replicability ensures that any generalized skyscraper contains uncountably many other skyscrapers as subsets. Both of the above properties will be essential in the construction of the design in a subsequent chapter.

The expression of path in three satellite-framed languages

Cross-linguistic studies of the lexicalization of motion tend to contrast satellite- with verb-framed languages (e.g. Slobin 1996; 2004; Cardini 2008; Özçalışkan & Slobin 2003; Kopecka 2004; Fargard et al. 2013, etc.) and concentrate less frequently on intra-typological analyses (but cf. e.g. Filipović 2007; Hasko 2010; Ibarretxe-Antuñano 2009; Ibarretxe-Antuñano & Hijazo-Gascón 2012). Even fewer studies contrast genetically related languages (but cf. e.g. Łozińska 2018). The main aim of this study was to establish the path-saliency cline of three satellite-framed languages: Polish, Russian, and English. The analysis was based on elicited data. The overall patterns of expressing the path of motion in the three languages were shown to be caused by their belonging to the same typological category. The differences could be attributed, to a large extent, to differences in the morphological structures and in the lexical repertoires of motion-coding expressions available to the speakers of the three languages. However, the analysis of descriptions of three specific spatial situations (i.e. vertical, boundary-crossing, and deictic relations) pointed to other factors that may influence path coding in the three languages. Thus, despite the satellite-verb character of the languages examined and the morpho-syntactic differences between them, all our participants, who were native speakers of the three languages examined, tended to code vertical relations by means of path verbs. The number of tokens of path verbs used to code this particular spatial relation was found to be higher than the number of tokens of path verbs used to code deictic or boundary-crossing motion.

Policy entrepreneurship across boundaries: a systematic literature review

Although policy entrepreneurs are assigned an important role in crossing policy boundaries and addressing complex problems, our understanding of the process is limited. This article systematically reviews 51 studies on conditions, strategies and implications of crossboundary entrepreneurship. Findings show that (1) the literature predominantly mentions issue promotion and coalition-building as crossboundary strategies; (2) vertical boundary-crossing is discussed more frequently than horizontal boundary-crossing; (3) the most reported boundary-crossing function is to expand issue arenas; (4) conditions that enable crossboundary strategies include institutional overlap, issue interpretation, power vacuum, overruling policies and lacking resources; and (5) implications of entrepreneurship include raised opposition, increased competition over leadership, augmented complexity hindering collective action, raised costs and resources, and issues regarding trust, legitimacy and authority. Policy entrepreneurship allows for micro-level insights in the emergence of crossboundary processes. We suggest future research to focus on causal processes between conditions, strategies and implications to better understand their interplay.

Full-Scale Cyclic Testing of Self-Centering Modular Panels for Seismic Resilient Structures

This paper presents a new seismic load-resisting system termed self-centering modular panel (SCMP) which provides lateral stiffness and self-centering stiffness for tension-only concentrically braced beam-through frames (TOCBBTFs). The SCMP is a posttensioned (PT) steel moment resisting frame, which consists of horizontal boundary elements (HBEs), vertical boundary elements (VBEs) and PT strands. The self-centering stiffness is provided by the PT HBE-to-VBE connections. Specimens of original TOCBBTF and TOCBBTF with SCMP were tested to investigate the function of the SCMP. The test results show that compared to the original TOCBBTF, the TOCBBTF with SCMP was capable of recentering after 4% drift of loading. Moreover, after severe cyclic loading and replacement of the damaged bracings, the repaired TOCBBTF with SCMP exhibited almost identical stiffness, strength and recentering ability to that of the original system.