Slow Conductance Relaxation in Insulating Granular Al: Evidence for Screening Effects

It is shown that the conductance relaxations observed in electrical field effect measurements on granular Al films are the sum of two contributions. One is sensitive to gate voltage changes and gives the already reported anomalous electrical field effect. The other one is independent of the gate voltage history and starts when the films are cooled down to low temperature. Their relative amplitude is strongly thickness dependent which demonstrates the existence of a finite screening length in our insulating films and allows its quantitative estimate (about 10nm at 4K). This metallic-like screening should be taken into account in the electron glass models of disordered insulators

Dynamic response of railway tracks in tunnel

International audiencePeriodically supported beams subjected to a moving load are often used for modelling the railway dynamics and analytical solutions have been developed for such modelling [3, 4]. More complex models can be constructed by including supports with damping or non-linear stiffness elements. This study deals with the dynamical modelling of non-ballasted railways, especially railways in tunnels. The model is developed as a dynamical system of multi-degree of freedom. Under the periodic assumption on the reaction force of the supports, the equation of motion for a periodically supported beam subjected to a moving load has been written. Then the Fourier transform has been used to solve this equation in case of damped supports. Analytical solutions have been established for the motion of the wheel and rail and also for the reaction force of the supports. The analytical solutions have been compared with in situ experimental measurements. The comparison shows that the theoretical results agree well with the measured results if damped supports are included in the model

Etude épidémiologique, clinique et thérapeutique des hydrocèles dans trois districts sanitaires de la région de Sikasso/Mali: Epidemiological, Clinical and Therapeutic Study of Hydroceles in Three Health Districts in the Sikasso Region / Mali

Context and objective. Hydrocele is one of the most common urogenital manifestations of lymphatic filariasis. It is a common cause of enlarged scrotum in the tropics. This study aims to describe the epidemiological, clinical and therapeutic aspects of hydroceles. Methods. This cross-sectional descriptive study of hydroceles in three endemic filarial Sikasso areas in Mali was conducted from November 2017 to December 2018. The variables studied were: frequency of hydrocele, age of patients, duration of evolution, type of anesthesia, surgical technique, volume, operative time and postoperative results. Results. Three hundred fifty-eight patients were operated on in fourteen months. The frequency of hydrocele‘s surgery was 31%. Their average age was 47.1 years old (extremes 4 months and 94 years). The duration of evolution was 10.7 years (extremes 6 months and 21 years). The right side was the most affected with 44.1% followed by the left side with 31.3%. Hydrocele was bilateral in 19%. Local anesthesia (with xylocaine 2%) was used in 88%. All patients underwent a successful vaginal resection. Conclusion. The hydrocele remains a common urological pathology in these endemic areas. The diagnosis is made after a long period of evolution of the disease. Treatment in outpatient surgery is undertaken using local anesthesia. These hydrocele management campaigns should be encouraged to treat the maximum number of patients. Contexte et objectif. L’hydrocèle constitue l’une des manifestations urogénitales les plus fréquentes de la filariose lymphatique. Elle est une cause fréquente de grosse bourse dans les régions tropicales. L’objectif de cette étude est de décrire les aspects épidémiologiques, cliniques et thérapeutiques des hydrocèles. Méthodes. Il s’agissait d’une étude transversale et descriptive sur les hydrocèles, réalisée entre novembre 2017 et décembre 2018 ; dans trois zones endémiques filariennes dans la région de SIKASSO au Mali. Les variables étudiées étaient : la fréquence de l’hydrocèle, l’âge des patients, la durée d’évolution, le type d’anesthésie, la technique chirurgicale, le volume, le temps opératoire et les résultats postopératoires. Résultats. Trois cent cinquante-huit patients ont été opérés en quatorze mois. L’intervention de l’hydrocèle rendait compte de 31% des activités chirurgicales. Leur âge moyen était de 47,1 ans (extrêmes 4 mois et 94 ans). La durée d’évolution était de 10,7 ans (extrêmes de 6 mois et 21 ans). Le testicule droit était le plus touché (44,1 %) suivi du côté gauche (31,3%). L’hydrocèle était bilatérale dans 19 %. L’anesthésie locale à la xylocaïne 2 % a été réalisée dans 88%. La résection vaginale a été réalisée chez tous les patients avec succès. Conclusion. L’hydrocèle reste une pathologie urologique fréquente en zone d’endémie filarienne. Le diagnostic se fait après une longue durée d’évolution de la maladie. Le traitement en chirurgie ambulatoire réalisée sous anesthésie locale a montré des résultats satisfaisants. Ces campagnes de prise en charge de l’hydrocèle sont à encourager pour pouvoir traiter le maximum de patients

Translanguaging and Public Service Encounters: Language Learning in the Library

This article explores the information desk of a city library as a site for language learning. Using a linguistic ethnographic approach, the interactions between a customer experience and information assistant and the many library users who approach her information desk were analysed. Findings are that, in addition to providing information about library resources, information desks are sites at which bits and pieces of different languages are taught and learned. Such language teaching and learning episodes created interactions of inclusion and welcome that went far beyond purely transactional information. Rather, language‐related episodes created moments of human contact and engagement, which were upheld through the translanguaging practices of interactants, the disposition and workplace competence of library staff, and the spatial ecology of the information desk. Furthermore, the article contributes to ongoing theoretical debates about translanguaging by noting that normativity and pressure toward uniformity are as much a part of languaging processes as creativity and flexibility. Our definition of translanguaging recognises the opposing pull of centrifugal and centripetal forces. The article ends by asking what schools, and language education, might learn from public libraries in creating arenas that maintain communitarianism, diversity of expression, and the development of civic skills

Attempting to distinguish between endogenous and contaminating cytokeratins in a corneal proteomic study

<p>Abstract</p> <p>Background</p> <p>The observation of cytokeratins (CK's) in mass spectrometry based studies raises the question of whether the identified CK is a true endogenous protein from the sample or simply represents a contaminant. This issue is especially important in proteomic studies of the corneal epithelium where several CK's have previously been reported to mark the stages of differentiation from corneal epithelial stem cell to the differentiated cell.</p> <p>Methods</p> <p>Here we describe a method to distinguish very likely endogenous from uncertain endogenous CK's in a mass spectrometry based proteomic study. In this study the CK identifications from 102 human corneal samples were compared with the number of human CK identifications found in 102 murine thymic lymphoma samples.</p> <p>Results</p> <p>It was anticipated that the CK's that were identified with a frequency of <5%, <it>i.e. </it>in less than one spot for every 20 spots analysed, are very likely to be endogenous and thereby represent a 'biologically significant' identification. CK's observed with a frequency >5% are uncertain endogenous since they may represent true endogenous CK's but the probability of contamination is high and therefore needs careful consideration. This was confirmed by comparison with a study of mouse samples where all identified human CK's are contaminants.</p> <p>Conclusions</p> <p>CK's 3, 4, 7, 8, 11, 12, 13, 15, 17, 18, 19, 20 and 23 are very likely to be endogenous proteins if identified in a corneal study, whilst CK's 1, 2e, 5, 6A, 9, 10, 14 and 16 may be endogenous although some are likely to be contaminants in a proteomic study. Further immunohistochemical analysis and a search of the current literature largely supported the distinction.</p

Territorial rights and colonial wrongs

What is wrong with colonialism? The standard—albeit often implicit—answer to this question has been that colonialism was wrong because it violated the territorial rights of indigenous peoples, where territorial rights were grounded on acquisition theories. Recently, the standard view has come under attack: according to critics, acquisition based accounts do not provide solid theoretical grounds to condemn colonial relations. Indeed, historically they were used to justify colonialism. Various alternative accounts of the wrong of colonialism have been developed. According to some, colonialism involved a violation of territorial rights grounded on legitimate state theory. Others reject all explanations of colonialism's wrongfulness based on territorial rights, and argue that colonial practices were wrong because they departed from ideals of economic, social, and political association. In this article, we articulate and defend the standard view against critics: colonialism involved a procedural wrong; this wrong is not the violation of standards of equality and reciprocity, but the violation of territorial rights; and the best foundation for such territorial rights is acquisition based, not legitimacy based. We argue that this issue is not just of historical interest, it has relevant implications for the normative evaluation of contemporary inequalities