109 research outputs found

    Comparing nonsynergy gamma models and interaction models to predict growth of emetic Bacillus cereus for combinations of pH and water activity values

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    This research aims to test the absence (gamma hypothesis) or occurrence of synergy between two growth-limiting factors, i.e., pH and water activity (aw), using a systematic approach for model selection. In this approach, preset criteria were used to evaluate the performance of models. Such a systematic approach is required to be confident in the correctness of the individual components of the combined (synergy) models. With Bacillus cereus F4810/72 as the test organism, estimated growth boundaries for the aw-lowering solutes NaCl, KCl, and glucose were 1.13 M, 1.13 M, and 1.68 M, respectively. The accompanying aw values were 0.954, 0.956, and 0.961, respectively, indicating that equal aw values result in similar effects on growth. Out of the 12 models evaluated using the preset criteria, the model of J. H. T. Luong (Biotechnol. Bioeng. 27:280–285, 1985) was the best model to describe the effect of aw on growth. This aw model and the previously selected pH model were combined into a gamma model and into two synergy models. None of the three models was able to describe the combined pH and aw conditions sufficiently well to satisfy the preset criteria. The best matches between predicted and experimental data were obtained with the gamma model, followed by the synergy model of Y. Le Marc et al. (Int. J. Food Microbiol. 73:219–237, 2002). No combination of models that was able to predict the impact of both individual and combined hurdles correctly could be found. Consequently, in this case we could not prove the existence of synergy nor falsify the gamma hypothesis

    Is philosophy of education a historical mistake? Connecting philosophy and education differently

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    In this article, I suggest that the question whether the proper place for philosophy of education is in the domain of philosophy or the domain of education cannot be resolved as long as we think of the connection between philosophy and education in terms of the idea of 'philosophy of education'. To substantiate this point, I look into the history of the idea of 'philosophy of education', both as a general idea and with regard to the way in which it became institutionalised in universities in the English-speaking world. I contrast this with the way in which the academic study of education developed in German-speaking countries in order to highlight that 'philosophy of education' is not the only way in which philosophy and education can be connected. Being aware that the connection between philosophy and education can be made differently not only provides a way out of the discussion about the proper identity and location of philosophy of education, but also hints at forms of philosophically informed scholarship that are more firmly based with the academic field of education rather than that they remain a halfway house in between philosophy and education

    Potassium‐ion‐selective fluorescent sensors to detect cereulide, the emetic toxin of B. cereus, in food samples and HeLa cells

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    We report the development of new chemical probes for cereulide, a toxic metabolite produced by specific strains of Bacillus cereus, through displacement of potassium cations from a preformed specific complex and a subsequent change in the fluorescence emission. For this purpose, we designed fluorescent probes for potassium cations that were suitable for displacement assays with cereulide from organic extracts. The fluorescence detection of natural cereulide in rice samples was achieved by using synthetic cereulide as a reference and a potassium fluorescent reporter, and this was found to be useful as a portable and fast method for the in situ detection of cereulide in food extracts. To study the fate of cereulide in live cells, we designed a procedure that was suitable for live‐cell microscopy imaging of HeLa cells by comparing the cellular location of the potassium fluorogenic probe, which stained intracellular endolysosomes, in the absence and presence of cereulide; we concluded that in the presence of cereulide, the fluorescence of the probe was decreased because of complexation of the potassium ions by cereulide.Ministerio de Econom&a y Competitividad, Spain (Projects CTQ2015-71353-R and AES-PI16/000496), Junta de Castilla y Lejn, Consejer&a de Educaci jn y Cultura y Fondo Social Europeo (Project BU232U13), and the European Commission, Seventh Framework Programme (Project SNIFFER FP7-SEC-2012–312411

    The development of Scotland’s Curriculum for Excellence: Amnesia and DĂ©jĂ  Vu

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    Scotland’s new Curriculum for Excellence (CfE) has been widely acknowledged as the most significant educational development in a generation, with the potential to transform learning and teaching in Scottish schools. In common with recent developments elsewhere, CfE seeks to re-engage teachers with processes of curriculum development, to place learning at the heart of the curriculum and to change engrained practices of schooling. This article draws upon well-established curriculum theory (notably the work of both Lawrence Stenhouse and A.V. Kelly) to analyse the new curriculum. We argue that by neglecting to take account of such theory, the curricular offering proposed by CfE is subject to a number of significant structural contradictions which may affect the impact that it ultimately exerts on learning and teaching; in effect, by ignoring the lessons of the past, CfE runs the risk of undermining the potential for real change

    Alternative futures and future alternatives for the philosophy of education: Introduction to the symposium

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    The three papers brought together in this invited symposium reflect on the future of philosophy of education, considering future alternatives and alternative futures. What is perhaps most striking about the three contributions is that they reflect on the future of philosophy of education from three distinct geographical locations. Peter Roberts, based in New Zealand, reflects on philosophy of education with an eye on developments in his own country, in Australia and in the wider region served by the Philosophy of Education Society of Australasia. Heesoon Bai and colleagues, based in Canada, take the situation in North America as their point of departure, albeit that their reflections aim at a truly global perspective
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