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    Gibberellin signaling mediates lateral root inhibition in response to K+-deprivation

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    The potassium ion (K+) is vital for plant growth and development, and K+-deprivation leads to reduced crop yields. Here we describe phenotypic, transcriptomic, and mutant analyses to investigate the signaling mechanisms mediating root architectural changes in Arabidopsis (Arabidopsis thaliana) Columbia. We showed effects on root architecture are mediated through a reduction in cell division in the lateral root (LR) meristems, the rate of LR initiation is reduced but LR density is unaffected, and primary root growth is reduced only slightly. This was primarily regulated through gibberellic acid (GA) signaling, which leads to the accumulation of growth-inhibitory DELLA proteins. The short LR phenotype was rescued by exogenous application of GA but not of auxin or by the inhibition of ethylene signaling. RNA-seq analysis showed upregulation by K+-deprivation of the transcription factors JUNGBRUNNEN1 (JUB1) and the C-repeat-binding factor (CBF)/dehydration-responsive element-binding factor 1 regulon, which are known to regulate GA signaling and levels that regulate DELLAs. Transgenic overexpression of JUB1 and CBF1 enhanced responses to K+ stress. Attenuation of the reduced LR growth response occurred in mutants of the CBF1 target gene SFR6, implicating a role for JUB1, CBF1, and SFR6 in the regulation of LR growth in response to K+-deprivation via DELLAs. We propose this represents a mechanism to limit horizontal root growth in conditions where K+ is available deeper in the soil

    Investigating and promoting trainee science teachers’ conceptual change of the nature of science with digital dialogue games “InterLoc”

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    The purpose of this study is to explore how an online-structured dialogue environment supported (OSDE) collaborative learning about the nature of science among a group of trainee science teachers in the UK. The software used (InterLoc) is a linear text-based tool, designed to support structured argumentation with openers and ‘dialogue moves’. A design-based research approach was used to investigate multiple sessions using InterLoc with 65 trainee science teachers. Five participants who showed differential conceptual change in terms of their Nature of Science (NOS) views were purposively selected and closely followed throughout the study by using key event recall interviews. Initially, the majority of participants held naïve views of NOS. Substantial and favourable changes in these views were evident as a result of the OSDE. An examination of the development of the five participants’ NOS views indicated that the effectiveness of the InterLoc discussions was mediated by cultural, cognitive, and experiential factors. The findings suggest that InterLoc can be effective in promoting reflection and conceptual change.InterLoc was developed by a team led by Andrew Ravenscroft with funding from the UK JISC (Joint Information Systems Committee) 'e-learning tools' programme, and from the JISC Capital Programme

    Creative pedagogies in digital STEAM practices: natural, technological and cultural entanglements for powerful learning and activism

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    This is the final version. Available on open access from Springer via the DOI in this recordThis paper delves deeply into the creative pedagogies which support cutting edge digital STEAM practice across primary and secondary school settings. It contextualises the research within current STEAM agendas including transdisciplinarity, and STEAM and technology and goes on to offer insight from the novel context of ocean learning to develop and extend a theorisation of creative pedagogies as entwining both creative teaching and teaching for creativity as embodied, democratic, dialogic and material processes. Intra-action between theory, praxis, nature, culture, the digital and humans enables an emergent perspective about changing the dynamics of power to develop ocean or environmental learning and related activism. Derived from research into an ocean education project, which aimed to develop students’ ocean literacy through the combined educative principles of creative pedagogies and digital technologies (Augmented and Virtual Realities), the research draws on data from six projects across primary and secondary school settings in Denmark, Spain and England. It used a ‘diffractive’ analytic technique, inspired by new materialist theory, to explore the messy mixtures of natural, cultural and technological environments that were being learned through. This involved the development of four material-dialogic assemblages each including diffractive switches. Each is presented first through a ‘piece’ which demonstrates each assemblage’s connection to the core question, followed by ‘ripples’, which briefly articulate the new learning and questions arising from that assemblage. The four assemblages cover the irresistibility of making kin, the relationships between lively bodies and virtual environments, the importance of spacetimematter in environmental edu-activism and trajectories between transience, stability and dialogic space. The paper leaves the reader/engager with a selection of prompts to highlight the research’s contribution to current STEAM agendas related to changing power dynamics, and to provoke reader/engagers’ own practices. These can include new pedagogies and activisms, as well as theoretical developments to the combined educative principles of creative pedagogies and digital technologies within STEAM education.Erasmus

    Stapled Peptides as HIF‐1α/p300 Inhibitors: Helicity Enhancement in the Bound State Increases Inhibitory Potency

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    Protein–protein interactions (PPIs) control virtually all cellular processes and have thus emerged as potential targets for development of molecular therapeutics. Peptide‐based inhibitors of PPIs are attractive given that they offer recognition potency and selectivity features that are ideal for function, yet, they do not predominantly populate the bioactive conformation, frequently suffer from poor cellular uptake and are easily degraded, for example, by proteases. The constraint of peptides in a bioactive conformation has emerged as a promising strategy to mitigate against these liabilities. In this work, using peptides derived from hypoxia‐inducible factor 1 (HIF‐1α) together with dibromomaleimide stapling, we identify constrained peptide inhibitors of the HIF‐1α/p300 interaction that are more potent than their unconstrained sequences. Contrary to expectation, the increased potency does not correlate with an increased population of an α‐helical conformation in the unbound state as demonstrated by experimental circular dichroism analysis. Rather, the ability of the peptide to adopt a bioactive α‐helical conformation in the p300 bound state is better supported in the constrained variant as demonstrated by molecular dynamics simulations and circular dichroism difference spectra

    In situ measurements of density fluctuations and compressibility in silica glass as a function of temperature and thermal history

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    In this paper, small-angle X-ray scattering measurements are used to determine the different compressibility contributions, as well as the isothermal compressibility, in thermal equilibrium in silica glasses having different thermal histories. Using two different methods of analysis, in the supercooled liquid and in the glassy state, we obtain respectively the temperature and fictive temperature dependences of the isotheraml compressibility. The values obtained in the glass and supercooled liquid states are very close to each other. They agree with previous determinations of the literature. The compressibility in the glass state slightly decreases with increasing fictive temperature. The relaxational part of the compressibility is also calculated and compared to previous determinations. We discussed the small differences between the different determinations

    Symptoms and Self-Care in Old Age

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    Self-care has recently come to be recognized as the predominant form of response to illness among the general population, but little is known regarding beliefs and practices of the aged. In this study, beliefs regarding the appropriate response to 53 common symptoms were investigated and contrasted to actual responses. Various forms of self-care were seen as appropriate responses to symptoms ranging from minor to potentially serious. Preference for self-care responses appears to be related to perceived severity of symptoms and the perceived effectiveness of available self-care responses.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66474/2/10.1177_073346488600500207.pd

    Random walks near Rokhsar-Kivelson points

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    There is a class of quantum Hamiltonians known as Rokhsar-Kivelson(RK)-Hamiltonians for which static ground state properties can be obtained by evaluating thermal expectation values for classical models. The ground state of an RK-Hamiltonian is known explicitly, and its dynamical properties can be obtained by performing a classical Monte Carlo simulation. We discuss the details of a Diffusion Monte Carlo method that is a good tool for studying statics and dynamics of perturbed RK-Hamiltonians without time discretization errors. As a general result we point out that the relation between the quantum dynamics and classical Monte Carlo simulations for RK-Hamiltonians follows from the known fact that the imaginary-time evolution operator that describes optimal importance sampling, in which the exact ground state is used as guiding function, is Markovian. Thus quantum dynamics can be studied by a classical Monte Carlo simulation for any Hamiltonian that is free of the sign problem provided its ground state is known explicitly.Comment: 12 pages, 9 figures, RevTe

    International Educators’ Perspectives on the Purpose of Science Education and the Relationship between School Science and Creativity

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    This is the author accepted manuscript. The final version is available from Taylor & Francis (Routledge) via the DOI in this record.Background: Creativity across all disciplines is increasingly viewed as a fundamental educational capability. Science can play a potentially important role in the nurturing of creativity. Research also suggests that creative pedagogy, including interdisciplinary teaching with Science and the Arts, can engage students with science. Previous studies into teachers’ attitudes to the relationship between science and creativity have been largely situated within national educational contexts. Purpose: This study, part of the large EU funded CREATIONs project, explores educators’ perspectives on the relationship between Science and Creativity across national contexts drawn from Europe and beyond. Sample and Methods: 270 educators, broadly defined to include primary (age 4-11) and secondary (age 11-18) teachers and trainee teachers, informal educators and teacher educators, responded to a survey designed to explore perceptions of the relationship between science and creativity. Respondents were a convenience sample recruited by project partners and through online media. The elements of the survey reported here included Likert-scale questions, open response questions, and ranking questions in the form of an electronic self-administered questionnaire. Exploratory factor analysis was used to develop a combined attitude scale labelled ‘science is creative’, with results compared across nationalities and phases of education. Open question responses were analysed thematically to allow more nuanced interpretation of the descriptive statistical findings. Results: The findings show broad agreement internationally and across phases that science is a creative endeavour, with a small number of educators disagreeing about the 3 relationship between science and creativity in the context of school science. Those who disagreed were usually secondary science teachers, from England, Malta or outside Europe (primarily from the United States). The role of scientific knowledge within creativity in science education was found to be contentious. Conclusions: That educators broadly see science as creative is unsurprising, but initial exploration of educators’ perspectives internationally shows some areas of difference. These were especially apparent for educators working in formal education, particularly relating to the role of knowledge with respect to creativity in science. With current interest in STEAM education, further investigation to understand potential mediating factors of national educational contexts on teachers’ perspectives with respect to the role of disciplinary knowledge(s) in creativity and their interaction in interdisciplinary teaching and learning, is recommended.European Commissio
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