2,125 research outputs found

    Experimenting with Law: Brecht on Copyright

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    Can one reject copyright law and be a qualified observer of its dispositives? This question was taken up by Bertolt Brecht in an intriguing essay concerning the litigation surrounding the film adaptation of The Threepenny Opera (1928). Brecht here develops an experimental observation around the nature of film adaptation and cultural production in copyright. While an experimental approach to law was in itself a subversive gesture, the specific legal process enabled him to expose the paradoxical ways in which the copyright system worked

    Towards the most general scalar-tensor theories of gravity: a unified approach in the language of differential forms

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    We use a description based on differential forms to systematically explore the space of scalar-tensor theories of gravity. Within this formalism, we propose a basis for the scalar sector at the lowest order in derivatives of the field and in any number of dimensions. This minimal basis is used to construct a finite and closed set of Lagrangians describing general scalar-tensor theories invariant under Local Lorentz Transformations in a pseudo-Riemannian manifold, which contains ten physically distinct elements in four spacetime dimensions. Subsequently, we compute their corresponding equations of motion and find which combinations are at most second order in derivatives in four as well as arbitrary number of dimensions. By studying the possible exact forms (total derivatives) and algebraic relations between the basis components, we discover that there are only four Lagrangian combinations producing second order equations, which can be associated with Horndeski's theory. In this process, we identify a new second order Lagrangian, named kinetic Gauss-Bonnet, that was not previously considered in the literature. However, we show that its dynamics is already contained in Horndeski's theory. Finally, we provide a full classification of the relations between different second order theories. This allows us to clarify, for instance, the connection between different covariantizations of Galileons theory. In conclusion, our formulation affords great computational simplicity with a systematic structure. As a first step we focus on theories with second order equations of motion. However, this new formalism aims to facilitate advances towards unveiling the most general scalar-tensor theories.Comment: 28 pages, 1 figure, version published in PRD (minor changes

    Flipped classroom based on objective structured clinical examinations analysis by undergraduate students of Pharmacology course from the Podiatry Degree improve their learning and assessment communication skills about medicines

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    Comunicación cartel con defensa oralWe aim to evaluate the impact of the individual and in-group analysis of OSCEs (filmed by other students) looking for correct and incorrect behaviours and contents in their learning of pharmacology. Summary of work and outcomes: A 5-year prospective study in which students of Pharmacology course from the Podiatry Degree analysed filmed OSCEs individually and in a group in a flipped classroom. Each group (max 5 students) analysed along 1 week a filmed OSCE, prepare a summary of correct and incorrect items related to clinical events, medicines uses, and people behaviours. The students presented their analysis results to the rest of the class. After each presentation, the other students of the class were encouraged to ask questions and after that, the students voluntarily answered a satisfaction survey. Result and Discussion: 405 students, 65.2% female, 20±5.3 years old were included. Students spend 13.4±5.4 h on making the filmed-OSCE analysis. The percentage of students satisfied with this way of studying pharmacology was 96.5%. OSCEs analysis by students increased their percentage of success in the final assessment in both OSCEs-related and OSCEs-non-related questions (+18.5% and +10.1%). Conclusion: Filmed Objective Structured Clinical Examinations analysis by undergraduate students on the Pharmacology course of Podiatry Degree improved their knowledge about medicines use and their communication skills during the assessment.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    Solar neutrino detection

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    More than 40 years ago, neutrinos where conceived as a way to test the validity of the solar models which tell us that stars are powered by nuclear fusion reactions. The first measurement of the neutrino flux, in 1968 in the Homestake mine in South Dakota, detected only one third of the expected value, originating what has been known as the Solar Neutrino Problem. Different experiments were built in order to understand the origin of this discrepancy. Now we know that neutrinos undergo oscillation phenomenon changing their nature traveling from the core of the Sun to our detectors. In the work the 40 year long saga of the neutrino detection is presented; from the first proposals to test the solar models to last real time measurements of the low energy part of the neutrino spectrum.Comment: 8 pages, 5 figures. III School on Cosmic Rays and Astrophysics August 25 to September 5, 2008 Arequipa (Peru) AIP conference proceedin

    Intrinsically disordered inhibitor of glutamine synthetase is a functional protein with random-coil-like pKa values

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    The sequential action of glutamine synthetase (GS) and glutamate synthase (GOGAT) in cyanobacteria allows the incorporation of ammonium into carbon skeletons. In the cyanobacterium Synechocystis sp. PCC 6803, the activity of GS is modulated by the interaction with proteins, which include a 65-residue-long intrinsically disordered protein (IDP), the inactivating factor IF7. This interaction is regulated by the presence of charged residues in both IF7 and GS. To understand how charged amino acids can affect the binding of an IDP with its target and to provide clues on electrostatic interactions in disordered states of proteins, we measured the pKa values of all IF7 acidic groups (Glu32, Glu36, Glu38, Asp40, Asp58, and Ser65, the backbone C-terminus) at 100 mM NaCl concentration, by using NMR spectroscopy. We also obtained solution structures of IF7 through molecular dynamics simulation, validated them on the basis of previous experiments, and used them to obtain theoretical estimates of the pKa values. Titration values for the two Asp and three Glu residues of IF7 were similar to those reported for random-coil models, suggesting the lack of electrostatic interactions around these residues. Furthermore, our results suggest the presence of helical structure at the N-terminus of the protein and of conformational changes at acidic pH values. The overall experimental and in silico findings suggest that local interactions and conformational equilibria do not play a role in determining the electrostatic features of the acidic residues of IF7.Ministerio de EconomĂ­a y Competitividad CTQ 2015-64445-R, BFU2013- 41712-P, BIO2016-75634PJunta de AndalucĂ­a BIO-284Generalitat Valenciana Prometeo 018/201
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