263 research outputs found

    Opening teaching landscapes: The importance of quality assurance in the delivery of open educational resources

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    Scholars are increasingly being asked to share teaching materials, publish in open access journals, network in social media, and reuse open educational resources (OER). The theoretical benefits of Open Educational Practices (OEP) have become understood in the academic community but thus far, the use of OER has not been rapidly adopted. We aim to understand the challenges academics face with in attempting to adopt OEP, and identify whether these are related to or stem from the functionalities afforded by current repositories of OER (ROER). By understanding what academics and experts consider good practices, we can develop guidelines for quality in the development of ROER. In this article we present the findings from a study surveying academics using OER and experts who develop and/or work with ROER. We conclude by suggesting a framework to enhance the development and quality of ROER

    Open Data as Open Educational Resources: Towards transversal skills and global citizenship

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    Open Data is the name given to datasets which have been generated by international organisations, governments, NGOs and academic researchers, and made freely available online and openly-licensed. These datasets can be used by educators as Open Educational Resources (OER) to support different teaching and learning activities, allowing students to gain experience working with the same raw data researchers and policy-makers generate and use. In this way, educators can facilitate students to understand how information is generated, processed, analysed and interpreted. This paper offers an initial exploration of ways in which the use of Open Data can be key in the development of transversal skills (including digital and data literacies, alongside skills for critical thinking, research, teamwork, and global citizenship), enhancing students’ abilities to understand and select information sources, to work with, curate, analyse and interpret data, and to conduct and evaluate research. This paper also presents results of an exploratory survey that can guide further research into Open Data-led learning activities. Our goal is to support educators in empowering students to engage, critically and collaboratively, as 21st century global citizens

    Stimulation of neutrophil functions by C5adesArg: an in vitro model of haemodialysis

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    Cuprophane membranes during haemodialysis significantly increase the plasma levels of C5adesArg (maximal 55 ÎŒg C5aadesArg/1 blood after 30 min) whereas Hemophane or Polysulphonemembranes induce only low plasma levels of C5adesArg. C5adesArg generated in vitro by yeast incubation of autologous plasma stimulates PMN chemotaxis and oxidative metabolism but has no effect on enzyme release. Preincubation of whole blood with C5adesArg causes aggregation and changed oxidative burst activity of the isolated PMN. These changes are similar to those found in cells from patients after haemodialysis with cuprophane membranes. So the elevated plasma levels of C5adesArg after haemodialysis explain some of the changes in PMN functions, but additional mechanisms have to be assumed

    Chronic exposure to cannabinoids during adolescence causes long-lasting behavioral deficits in adult mice

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    Regular use of marijuana during adolescence enhances the risk of long-lasting neurobiological changes in adulthood. The present study was aimed at assessing the effect of long-term administration of the synthetic cannabinoid WIN55212.2 during adolescence in young adult mice. Adolescent mice aged 5 weeks were subjected daily to the pharmacological action of WIN55212.2 for 3 weeks and were then left undisturbed in their home cage for a 5-week period and finally evaluated by behavioral testing. Mice that received the drug during adolescence showed memory impairment in the Morris water maze, as well as a dose-dependent memory impairment in fear conditioning. In addition, the administration of 3 mg/kg WIN55212.2 in adolescence increased adult hippocampal AEA levels and promoted DNA hypermethylation at the intragenic region of the intracellular signaling modulator Rgs7, which was accompanied by a lower rate of mRNA transcription of this gene, suggesting a potential causal relation. Although the concrete mechanisms underlying the behavioral observations remain to be elucidated, we demonstrate that long-term administration of 3 mg/kg of WIN during adolescence leads to increased endocannabinoid levels and altered Rgs7 expression in adulthood and establish a potential link to epigenetic changes.Beca Ramón y Caja

    Chemical probing of thiotetronate bio-assembly

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    Chemical ‘chain termination’ probes were utilised for the investigation of thiotetronate antibiotic biosynthesis in the filamentous bacteria Lentzea sp. and Streptomyces thiolactonus NRRL 15439. The use of these tools led to the capture of biosynthetic intermediates involved in the thiotetronate polyketide backbone assembly, providing first insights into substrate specificity and in vivo intermediate processing by unusual iterative synthases

    GUI Matlab para o cålculo de funçÔes de Bessel usando fraçÔes continuadas

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    [EN] Higher order Bessel functions are prevalent in physics and engineering and there exist different methods to evaluate them quickly and efficiently. Two of these methods are Miller's algorithm and the continued fractions algorithm. Miller's algorithm uses arbitrary starting values and normalization constants to evaluate Bessel functions. The continued fractions algorithm directly computes each value, keeping the error as small as possible. Both methods respect the stability of the Bessel function recurrence relations. Here we outline both methods and explain why the continued fractions algorithm is more efficient. The goal of this paper is both (1) to introduce the continued fractions algorithm to physics and engineering students and (2) to present a MATLAB GUI (Graphic User Interface) where this method has been used for computing the Semi-integer Bessel Functions and their zeros.[PT] FunçÔes de Bessel de ordem mais alta sĂŁo recorrentes em fĂ­sica e nas engenharias, sendo que hĂĄ diferentes mĂ©todos para calculĂĄ-las de maneira rĂĄpida e eficiente. Dois destes mĂ©todos sĂŁo o algoritmo de Miller e o algoritmo de fraçÔes continuadas. O primeiro faz uso de valores iniciais e constantes de normalização arbitrĂĄrios, enquanto o segundo o faz calculando cada valor diretamente, minimizando tanto quanto possĂ­vel o erro. Ambos respeitam a estabilidade das relaçÔes de recorrĂȘncia das funçÔes de Bessel. Neste trabalho descrevemos ambos os mĂ©todos e explicamos a razĂŁo pela qual o algoritmo das fraçÔes continuadas Ă© mais eficiente. O objetivo do artigo Ă© (1) introduzir o algoritmo de fraçÔes continuadas para estudantes de fĂ­sica e das engenharias e (2) apresentar um GUI (Graphic User Interface) em Matlab no qual este mĂ©todo foi utilizado para calcular funçÔes de Bessel semi-inteiras e seus zeros.The authors wish to thank the financial support received from the Universidad PolitĂ©cnica de Valencia under grant PAID-06-09-2734, from the Ministerio de Ciencia e InnovaciĂłn through grant ENE2008-00599 and specially from the Generalitat Valenciana under grant reference 3012/2009.Hernandez Vargas, E.; Commeford, K.; PĂ©rez Quiles, MJ. (2011). MATLAB GUI for computing Bessel functions using continued fractions algorithm. Revista Brasileira de Ensino de FĂ­sica. 33(1):1303-1311. https://doi.org/10.1590/S1806-11172011000100003S13031311331Giladi, E. (2007). Asymptotically derived boundary elements for the Helmholtz equation in high frequencies. Journal of Computational and Applied Mathematics, 198(1), 52-74. doi:10.1016/j.cam.2005.11.024Havemann, S., & Baran, A. J. (2004). Calculation of the phase matrix elements of elongated hexagonal ice columns using the T-matrix method. Journal of Quantitative Spectroscopy and Radiative Transfer, 89(1-4), 87-96. doi:10.1016/j.jqsrt.2004.05.014Segura, J., FernĂĄndez de CĂłrdoba, P., & Ratis, Y. L. (1997). A code to evaluate modified bessel functions based on thecontinued fraction method. Computer Physics Communications, 105(2-3), 263-272. doi:10.1016/s0010-4655(97)00069-6Bastardo, J. L., Abraham Ibrahim, S., FernĂĄndez de CĂłrdoba, P., UrchueguĂ­a Schölzel, J. F., & Ratis, Y. L. (2005). Evaluation of Fresnel integrals based on the continued fractions method. Applied Mathematics Letters, 18(1), 23-28. doi:10.1016/j.aml.2003.12.009Barnett, A. R., Feng, D. H., Steed, J. W., & Goldfarb, L. J. B. (1974). Coulomb wave functions for all real η and ϱ. Computer Physics Communications, 8(5), 377-395. doi:10.1016/0010-4655(74)90013-
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