2,927 research outputs found

    The Professor Behind the Screen: Four Case Studies of Online Teaching in Business.

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    Although online education in postsecondary education is not new, the number of online courses and programs has grown especially fast in recent years. This shift toward online education has drawn strong supporters as well as critics: some see promise in the immediate and flexible nature of the online environment, while others question the quality of online courses. The debate, in fact, hinges on teaching, just as in face-to-face settings. However, little systematic research has investigated online teaching through the eyes of instructors, and literature about online teaching is based largely on speculation and lacks complexity and depth. The central aim in this study was to examine online teaching from the perspectives of instructors themselves in order to understand pedagogical decisions, views of online education, and environmental factors influencing teaching. Case studies of four instructors at two institutions were developed. Each instructor taught a fully online, asynchronous undergraduate business course during Fall 2013. I gained access to course websites to view course materials and observe communication between the instructor and students. During the semester, I interviewed each instructor four times using a semi-structured interview format. The four case studies were composed separately, each with thick description that helped create a detailed and contextualized narrative. In addition to the case studies, I present a crosscase analysis describing themes and offering insights into the constraints and affordances of teaching online. The cross-case analysis contributed to the development of a theoretical framework for studying online teaching. Specifically, I propose an ecology model of online teaching accounting for contextual factors (e.g., institutional setting, instructor background) shaping teaching decisions, experiences, and beliefs in the asynchronous online teaching environment. This inquiry has meaningful implications for practice and research. First, knowing how instructors design courses and think about the online teaching-learning environment can inform the work of faculty development staff who train and support instructors and shape institutional culture related to teaching. Second, insights from this exploratory study can strengthen future research seeking to answer evaluative or causal questions by revealing essential variables to consider when examining the processes and outcomes of online education.PhDHigher EducationUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/111535/1/inbe_1.pd

    Reconstitution of recombination-associated DNA synthesis with human proteins.

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    The repair of DNA breaks by homologous recombination is a high-fidelity process, necessary for the maintenance of genome integrity. Thus, DNA synthesis associated with recombinational repair must be largely error-free. In this report, we show that human DNA polymerase delta (δ) is capable of robust DNA synthesis at RAD51-mediated recombination intermediates dependent on the processivity clamp PCNA. Translesion synthesis polymerase eta (η) also extends these substrates, albeit far less processively. The single-stranded DNA binding protein RPA facilitates recombination-mediated DNA synthesis by increasing the efficiency of primer utilization, preventing polymerase stalling at specific sequence contexts, and overcoming polymerase stalling caused by topological constraint allowing the transition to a migrating D-loop. Our results support a model whereby the high-fidelity replicative DNA polymerase δ performs recombination-associated DNA synthesis, with translesion synthesis polymerases providing a supportive role as in normal replication

    Dynamic regulation of integrin activation by intracellular and extracellular signals controls oligodendrocyte morphology

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    RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are.Abstract Background Myelination requires precise control of oligodendrocyte morphology and myelin generation at each of the axons contacted by an individual cell. This control must involve the integration of extracellular cues, such as those on the axon surface, with intrinsic developmental programmes. We asked whether integrins represent one class of oligodendrocyte cell-surface receptors able to provide this integration. Results Integrins signal via a process of activation, a conformational change that can be induced either by "outside-in" signals comprising physiological extracellular matrix ligands (mimicked by the pharmacological use of the divalent cation manganese) or "inside-out" signalling molecules such as R-Ras. Increasing levels of outside-in signalling via the laminin receptor α6β1 integrin were found to promote oligodendrocyte processing and myelin sheet formation in culture. Similar results were obtained when inside-out signalling was increased by the expression of a constitutively-active R-Ras. Inhibiting inside-out signalling by using dominant-negative R-Ras reduces processes and myelin sheets; importantly, this can be partially rescued by the co-stimulation of outside-in signalling using manganese. Conclusion The balance of the equilibrium between active and inactive integrins regulates oligodendrocyte morphology, which is itself regulated by extrinsic and intrinsic cues so providing a mechanism of signal integration. As laminins capable of providing outside-in signals are present on axons at the time of myelination, a mechanism exists by which morphology and myelin generation might be regulated independently in each oligodendrocyte process.Peer Reviewe

    The Fundamental Plane in RX J0142.0+2131: a galaxy cluster merger at z=0.28

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    We present the Fundamental Plane (FP) in the z = 0.28 cluster of galaxies RX J0142.0+2131. There is no evidence for a difference in the slope of the FP when compared with the Coma cluster, although the internal scatter is larger. On average, stellar populations in RX J0142.0+2131 have rest-frame V-band mass-to-light ratios (M/L_V) 0.29+-0.03 dex lower than in Coma. This is significantly lower than expected for a passively-evolving cluster formed at z_f=2. Lenticular galaxies have lower average M/L_V and a distribution of M/L_V with larger scatter than ellipticals. Lower mass-to-light ratios are not due to recent star formation: our previous spectroscopic observations of RX J0142.0+2131 E/S0 galaxies showed no evidence for significant star-formation within the past ~4 Gyr. However, cluster members have enhanced alpha-element abundance ratios, which may act to decrease M/L_V. The increased scatter in the RX J0142.0+2131 FP reflects a large scatter in M/L_V implying that galaxies have undergone bursts of star formation over a range of epochs. The seven easternmost cluster galaxies, including the second brightest member, have M/L_V consistent with passive evolution and z_f = 2. We speculate that RX J0142.0+2131 is a cluster-cluster merger where the galaxies to the east are yet to fall into the main cluster body or have not experienced star formation as a result of the merger.Comment: 4 pages, 2 figures, accepted for publication in ApJ Letter

    “Stewards of the future: accompanying the rising tide of young voices by setting youth-inclusive research agendas in sustainability research”

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    Background From the worldwide youth-led climate strikes of 2018–2019 to the student-initiated austerity protests in Chile in 2019, it is undeniable that young people have been protagonists in pressuring for social change towards greater sustainability in recent years. This piece reflects on youth as agents of social-ecological change, and what researchers can learn from the rise in youth-led social movements demanding action in the face of global sustainability challenges. The study of sustainability problems like climate change and biodiversity loss, intrinsically requires consideration of inter-generational equity. However, despite 50% of the global population being under 30 years old, youth are often not included explicitly as actors in environmental social sciences and sustainability-related research. Here we discuss why explicitly considering young people as distinct actors during the research process is important, as it allows researchers to engage in just and inclusive work whilst at the same time accounting for important agents of change in complex social-ecological systems. Results As a framework for our inquiry we present the themes which emerged during a series of international meetings and forums on sustainability challenges and youth in 2019, a year characterized by world-wide youth mobilization. Our briefing spans the United Nations Youth 2019 Climate Action Summit, the post-2020 meetings organized by the youth branch of the Convention of Biological Diversity (CBD), the UNESCO Man and Biosphere Youth forums and the results from the Global Shapers Survey of the World Economic Forum. Conclusions We argue that if researchers wish to facilitate youth-inclusive evidence-based decision making, research agendas must address knowledge gaps highlighted by institutional efforts to incorporate youth concerns within global sustainability policy, a recommendation that is even more relevant in the light of the COVID-19 crisis. We draw on the themes which emerged in our analysis of international youth meetings to provide recommendations for research agendas which account both for young actors as both passive and active components of social-ecological change and we propose a more inclusive and holistic study of coupled natural-human systems.publishedVersio

    School development through democratic involvement and group-approach in migrant dominated areas: experiences from Raadmandsgades Skole og Heimdalsgades Overbygningsskole in Copenhagen City, Denmark

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    Copenhagen City has since 2000 worked to fulfill policy aims and visions for integration in a democratic society. This integration provides equal opportunities in education, where teachers are able to empower pupils with ethnic minority background. The Copenhagen mayor for education and schools Per Bregengaard will focus on this issue. Two schools give examples of how they work. Raadmandsgades School is a primary school for 6-14 years students. They integrate the minority children in language groups. The other school Heimdalsgades Overbygningsskole is a secondary school with 14-17 years old pupils. It has innovated the curriculum and the students take part in the decisions of the school. Finally a consultant from the Development and Planning Unit in the Educational Department in Copenhagen City will explain the efforts to perform a special Copenhagen PISA survey and a massive in-service training for the teacher

    Integrins direct Src family kinases to regulate distinct phases of oligodendrocyte development

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    Specific integrins expressed on oligodendrocytes, the myelin-forming cells of the central nervous system, promote either differentiation and survival or proliferation by amplification of growth factor signaling. Here, we report that the Src family kinases (SFKs) Fyn and Lyn regulate each of these distinct integrin-driven behaviors. Fyn associates with α6β1 and is required to amplify platelet-derived growth factor survival signaling, to promote myelin membrane formation, and to switch neuregulin signaling from a phosphatidylinositol 3-kinase to a mitogen-activated protein kinase pathway (thereby changing the response from proliferation to differentiation). However, earlier in the lineage Lyn, not Fyn, is required to drive αVβ3-dependent progenitor proliferation. The two SFKs respond to integrin ligation by different mechanisms: Lyn, by increased autophosphorylation of a catalytic tyrosine; and Fyn, by reduced Csk phosphorylation of the inhibitory COOH-terminal tyrosine. These findings illustrate how different SFKs can act as effectors for specific cell responses during development within a single cell lineage, and, furthermore, provide a molecular mechanism to explain similar region-specific hypomyelination in laminin- and Fyn-deficient mice
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