‘What is the Purpose of Feedback when Revision is not Expected?’ A Case Study of Feedback Quality and Study Design in a First Year Master's Programme

This article presents a qualitative case study of feedback practices in the first year of a two-year master's programme. Writing and feedback are viewed as contextualized cultural practices shaped by factors at macro, meso and micro level. The empirical data consists of a text corpus of students’ essays and teachers’ comments, supplemented by interviews. Initial findings showed a discrepancy between the considerable amount of comments given by the teachers and the students’ lack of use of the feedback they received. The text analysis, based primarily on Hattie and Timperley’s (2007) model of feedback revealed several features of the feedback that counteracted learning, but a major problem was unclear goals for the writing combined with a study design that did not include revision of student texts

Opportunities and challenges of dialogic pedagogy in art museum education

The aim of this interpretative, qualitative research study is to investigate affordances and constraints of dialogic pedagogy in the museums, as well as its broader contribution to society today.  The background is my involvement in a Danish development project called ‘Museums and Cultural Institutions as Spaces for Citizenship,’ initiated by seven art museum educators in Copenhagen and supported by the Ministry of Culture. Denmark has a strong dialogic tradition dating back to Grundtvig’s belief in the power of ´the oral word’ to foster democratic ‘Bildung.’ Museum education, on the other hand, has a long tradition of monologic transmission. Still, a more participatory pedagogy has been gaining ground over many years. This study is based on the observations of three-hour-long teaching sessions in seven museums and has a Bakhtinian framework. While the overall analysis builds on the whole project, two cases are discussed in more detail. The overarching research question is how central aspects of dialogic pedagogy played out in an art museum context and its opportunities and challenges. The subquestions focus on three central Bakhtinian concepts: How did the educators facilitate multivoicedness during the short museum visits? What role did difference and disagreement play? What opportunities emerged for students to develop internally persuasive discourse? I have chosen these concepts because they are central in dialogism and combined them because they are closely connected in Bakhtin’s work. The final reflections open a wider perspective of how dialogic museum education may contribute to overarching functions of education: qualification, socialization, and subjectification. Key findings were that the museum educators’ transition from traditional to dialogic pedagogy was enhanced by their genuine interest in hearing students’ voices. They succeeded in engaging students in multivoiced dialogues but with a tendency towards harmonization rather than the exploration of diversity and difference. The practical aesthetic workshops offered unique opportunities for students to develop their internally persuasive word, i.e., by replacing authoritative interpretations of artworks with their own. Challenges experienced by the educators were, e.g., the dilemmas between preplanning and student choice and between disseminating their professional art knowledge and facilitating students’ meaning making and creativity. In contrast, students found the lack of workshop follow-up problematic. The article provides deeper insight into museums as an alternative pedagogical arena. Museum educators and non-museum classroom teachers may find it useful for cultivating greater dialogic interactions in respective learning contexts

The politics of biomass energy in California: how external benefits are used to support an economically marginal sector

Since the 1990s, there has been a decline in biomass energy generation in California. In order to promote state governmental policies aiming to increase biomass energy generation in California, the sector has been linked to a series of external benefits that biomass energy purportedly brings. Through document analysis, semi-structured interviews, and participant observation, five distinct external benefits were identified that have been used to promote the biomass energy sector. These external benefits are: renewable energy generation, air quality improvements, promotion of forest restoration and fuel removal projects, disposal of wood waste from agricultural and forestry sectors, and rural economic development. This study finds that the external benefits that are found in stakeholder discussions and legislative language reflect current events and politics that impact California, particularly as they relate to wildfire and forest management. There were three notable complications to creating policies that support biomass energy: disagreements about where along the supply chain biomass energy should be subsidized; questions centered on whether external benefits justify policy initiatives; and doubts about whether the external benefits claimed by biomass energy proponents were the best way to meet policy objectives

The mechanism of porosity formation during solvent-mediated phase transformations

Solvent-mediated solid-solid phase transformations often result in the formation of a porous medium, which may be stable on long time scales or undergo ripening and consolidation. We have studied replace- ment processes in the KBr-KCl-H2O system using both in situ and ex situ experiments. The replacement of a KBr crystal by a K(Br,Cl) solid solution in the presence of an aqueous solution is facilitated by the gen- eration of a surprisingly stable, highly anisotropic and connected pore structure that pervades the product phase. This pore structure ensures efficient solute transport from the bulk solution to the reacting KBr and K(Br,Cl) surfaces. The compositional profile of the K(Br,Cl) solid solu- tion exhibits striking discontinuities across disc-like cavities in the product phase. Similar transformation mechanisms are probably important in con- trolling phase transformation processes and rates in a variety of natural and man-made systems.Comment: 22 pages, 7 figure

ER/K linked GPCR-G protein fusions systematically modulate second messenger response in cells.

FRET and BRET approaches are well established for detecting ligand induced GPCR-G protein interactions in cells. Currently, FRET/BRET assays rely on co-expression of GPCR and G protein, and hence depend on the stoichiometry and expression levels of the donor and acceptor probes. On the other hand, GPCR-G protein fusions have been used extensively to understand the selectivity of GPCR signaling pathways. However, the signaling properties of fusion proteins are not consistent across GPCRs. In this study, we describe and characterize novel sensors based on the Systematic Protein Affinity Strength Modulation (SPASM) technique. Sensors consist of a GPCR and G protein tethered by an ER/K linker flanked by FRET probes. SPASM sensors are tested for the β2-, α1-, and α2- adrenergic receptors, and adenosine type 1 receptor (A1R), tethered to Gαs-XL, Gαi2, or Gαq subunits. Agonist stimulation of β2-AR and α2-AR increases FRET signal comparable to co-expressed FRET/BRET sensors. SPASM sensors also retain signaling through the endogenous G protein milieu. Importantly, ER/K linker length systematically tunes the GPCR-G protein interaction, with consequent modulation of second messenger signaling for cognate interactions. SPASM GPCR sensors serve the dual purpose of detecting agonist-induced changes in GPCR-G protein interactions, and linking these changes to downstream signaling

Compaction dynamics in ductile granular media

Ductile compaction is common in many natural systems, but the temporal evolution of such systems is rarely studied. We observe surprising oscillations in the weight measured at the bottom of a self-compacting ensemble of ductile grains. The oscillations develop during the first ten hours of the experiment, and usually persist through the length of an experiment (one week). The weight oscillations are connected to the grain--wall contacts, and are directly correlated with the observed strain evolution and the dynamics of grain--wall contacts during the compaction. Here, we present the experimental results and characteristic time constants of the system, and discuss possible reasons for the measured weight oscillations.Comment: 11 pages, 14 figure

Multiple Breathers on a Vortex Filament

In this paper we investigate the correspondence between the Da Rios-Betchov equation, which appears in the three-dimensional motion of a vortex filament, and the nonlinear Schrödinger equation. Using this correspondence we map a set of solutions corresponding to breathers in the nonlinear Schrödinger equation to waves propagating along a vortex filament. The work presented generalizes the recently derived family of vortex configurations associated with these breather solutions to a wider class of configurations that are associated with combination homoclinic/heteroclinic orbits of the 1D self-focussing nonlinear Schrödinger equation. We show that by considering these solutions of the governing nonlinear Schrödinger equation, highly nontrivial vortex filament configurations can be obtained that are associated with a pair of breather excitations. These configurations can lead to loop-like excitations emerging from an otherwise weakly perturbed helical vortex. The results presented further demonstrate the rich class of solutions that are supported by the Da Rios-Betchov equation that is recovered within the local induction approximation for the motion of a vortex filament

Crystal growth in confinement

The growth of crystals confined in porous or cellular materials is ubiquitous in Nature and industry. Confinement affects the formation of biominerals in living organisms, of minerals in the Earth's crust and of salt crystals damaging porous limestone monuments, and is also used to control the growth of artificial crystals. However, the mechanisms by which confinement alters crystal shapes and growth rates are still not elucidated. Based on novel \textit{in situ} optical observations of (001) surfaces of NaClO$_3$ and CaCO$_3$ crystals at nanometric distances from a glass substrate, we demonstrate that new molecular layers can nucleate homogeneously and propagate without interruption even when in contact with other solids, raising the macroscopic crystal above them. Confined growth is governed by the peculiar dynamics of these molecular layers controlled by the two-dimensional transport of mass through the liquid film from the edges to the center of the contact, with distinctive features such as skewed dislocation spirals, kinetic localization of nucleation in the vicinity of the contact edge, and directed instabilities. Confined growth morphologies can be predicted from the values of three main dimensionless parameters