Demonstration of the Lateral AC Skin Effect Using a Pickup Coil

We present a simple demonstration of the skin effect by observing the current distribution in a wide rectangular strip conductor driven at frequencies in the 0.25–5 kHz range. We measure the amplitude and phase of the current distribution as a function of the transverse position and find that they agree well with numerical simulations: The current hugs the edges of the strip conductor with a significant variation in phase across the width. The experimental setup is simple, uses standard undergraduate physics instructional laboratory equipment, and is easy to implement as a short in-class demonstration. Our study is motivated by modeling ac magnetic near fields in the vicinity of a rectangular trace on an atom chip

L’insertion professionnelle des enseignants en éducation physique et à la santé au primaire et au secondaire au Québec

Dans ce projet de maîtrise, nous nous intéressons au processus d’insertion professionnelle des enseignants débutants en éducation physique et à la santé. Plus précisément, nous cherchons à identifier les principaux facteurs influençant l’insertion professionnelle ainsi que les savoirs issus de la formation initiale mobilisés lors de cette étape cruciale. Depuis plusieurs années, le Québec connaît différents changements économiques et politiques. Ceux-ci touchent le monde de l’éducation et se traduisent notamment par des réformes éducatives engendrant de nombreuses transformations dans l’enseignement (Lessard et Tardif, 2004). Nombre d’écrits exposent ces nouveaux défis auxquels les enseignants doivent faire face, notamment la complexification de la tâche enseignante, ce qui a amené plusieurs chercheurs à vouloir approfondir la phase d’insertion professionnelle, et les difficultés qui s’y rattachent (De Stercke, 2014; Mukamurera, 2011, Mukamurera, Bourque et Gingras, 2008). Plusieurs constatent ainsi que la situation est marquée entre autres par l’épuisement professionnel et le décrochage des enseignants, et que la problématique est similaire dans d’autres pays (Karsenti, et coll, 2008; Cattonar, 2008). Cependant, peu d’études se concentrent au Québec sur l’insertion professionnelle au sein du contexte singulier de l’éducation physique et à la santé (ÉPS) (Grenier et coll, 2014; Spallanzani et coll, 2012; Blankenship et Coleman, 2009). Il nous semble donc pertinent de nous pencher sur la situation et de dresser un portrait représentatif du Québec. Afin d’y parvenir, notre cadre théorique est conçu autour du modèle multidimensionnel de l'insertion de Mukamurera (2013). Les dimensions de ce modèle seront mises en relation avec la perception et le vécu de chacun des participants quant à leur insertion ainsi qu’avec les savoirs issus de leur formation initiale. Nous espérons que cela nous permettra de décrire les conditions d’insertion professionnelle des enseignants au primaire et au secondaire en ÉPS au Québec, d'identifier et d’analyser les facteurs d’influence de l’expérience de l’insertion professionnelle ainsi que les savoirs mobilisés lors de cette étape. Dans le cadre de cette recherche interprétative nous avons adopté une approche qualitative afin de parvenir à mieux comprendre la réalité de ces enseignants en début de carrière. Les 14 participants constituant l'échantillon ont été choisis sur base volontaire et ont été soumis à un entretien semi-dirigé dont les questions ont été élaborées en fonction des dimensions du modèle de Mukamurera (2013). Le traitement des données s'est déroulé dans une logique inductive, et leur analyse, par contenu thématique grâce au logiciel QDA-Miner. À l’issue des entretiens, l’on peut établir que la perception de la formation initiale est mitigée. Les enseignants semblent avoir apprécié les moments sur le terrain, mais ont trouvé plusieurs cours trop théoriques et peu réalistes. Les résultats obtenus ont également permis de dresser un portrait global de l’insertion professionnelle en ÉPS, et d’identifier les structures en jeux dans l’insertion, et donc, les facteurs d’influence basée majoritairement sur le soutien des nouveaux enseignants.In this research, we are interested in the process of professional induction of new physical education teachers. More precisely, we seek to identify the main factors influencing their professional induction as well as their perception on the knowledge acquired during their initial training and mobilized during this crucial stage. Thus, for several years, Quebec has undergone various economic and political changes. They affected the world of education and brought educational reforms, resulting in many transformations in education (Lessard and Tardif, 2004). Many writers expose these new challenges that teachers face, including the complexity of the teaching task, which has led several researchers to want to deepen the process of induction and the difficulties associated (De Stercke , 2014, Mukamurera, 2011, Mukamurera, Bourque and Gingras, 2008). Several find that the situation is marked, among other things, by burnout and dropping out of teachers, but also its transposition in other countries (Karsenti, et al., 2008; Cattonar, 2008). However, few studies focus on professional induction within the singular context of physical education and health (Grenier et al., 2014, Spallanzani et al., 2012, Blankenship and Coleman, 2009). It therefore seems appropriate to look at the situation and draw a representative portrait of Quebec. To achieve this, our theoretical framework is designed around the multidimensional model of Mukamurera (2013). The dimensions of this model will be related to the perception and the experience of each participant as to their induction as well as the knowledge resulting from their initial training. We hope that this will allow us to describe the conditions of professional induction of elementary and high school teachers in Quebec, to identify and analyze the factors influencing their professional induction experience and the knowledge mobilized during this stage. As part of this interpretative research, we have adopted a qualitative approach in order to better understand the reality of these teachers at the beginning of their careers. The fourteen participants in the sample were selected on a voluntary basis and were subjected to a semi-structured interview whose questions were developed according to the dimensions of the Mukamurera model (2013). The processing of the data took place in an inductive logic, and their analysis, by thematic content with the QDA-Miner software. It can be established that the perception of initial training is mixed. Teachers seem to have enjoyed the moments on the ground, but found several courses too theoretical and unrealistic. The results obtained also gave an overall picture of the induction process and to identify the structures that may influence the induction and the programs that offer support the new teachers

The NOD mouse beyond autoimmune diabetes

Autoimmune diabetes arises spontaneously in Non-Obese Diabetic (NOD) mice, and the pathophysiology of this disease shares many similarities with human type 1 diabetes. Since its generation in 1980, the NOD mouse, derived from the Cataract Shinogi strain, has represented the gold standard of spontaneous disease models, allowing to investigate autoimmune diabetes disease progression and susceptibility traits, as well as to test a wide array of potential treatments and therapies. Beyond autoimmune diabetes, NOD mice also exhibit polyautoimmunity, presenting with a low incidence of autoimmune thyroiditis and Sjögren’s syndrome. Genetic manipulation of the NOD strain has led to the generation of new mouse models facilitating the study of these and other autoimmune pathologies. For instance, following deletion of specific genes or via insertion of resistance alleles at genetic loci, NOD mice can become fully resistant to autoimmune diabetes; yet the newly generated diabetes-resistant NOD strains often show a high incidence of other autoimmune diseases. This suggests that the NOD genetic background is highly autoimmune-prone and that genetic manipulations can shift the autoimmune response from the pancreas to other organs. Overall, multiple NOD variant strains have become invaluable tools for understanding the pathophysiology of and for dissecting the genetic susceptibility of organ-specific autoimmune diseases. An interesting commonality to all autoimmune diseases developing in variant strains of the NOD mice is the presence of autoantibodies. This review will present the NOD mouse as a model for studying autoimmune diseases beyond autoimmune diabetes

Linewidth of single photon transitions in Mn12_{12}-acetate

We use time-domain terahertz spectroscopy to measure the position and linewidth of single photon transitions in Mn$_{12}$-acetate. This linewidth is compared to the linewidth measured in tunneling experiments. We conclude that local magnetic fields (due to dipole or hyperfine interactions) cannot be responsible for the observed linewidth, and suggest that the linewidth is due to variations in the anisotropy constants for different clusters. We also calculate a lower limit on the dipole field distribution that would be expected due to random orientations of clusters and find that collective effects must narrow this distribution in tunneling measurements.Comment: 5 pages, accepted to Physical Review

Potential impact of a nonavalent HPV vaccine on the occurrence of HPV-related diseases in France

International audienceBackground : Human Papillomavirus (HPV) infection is known to be associated with a number of conditions including cervical, vaginal, vulvar, penile, anal neoplasias and cancers, oropharynx cancers and genitals warts (GW). Two prophylactic vaccines are currently available: a bivalent vaccine designed to prevent HPV type 16 and 18 infection and a quadrivalent vaccine targeting HPV 6, 11, 16, and 18. In France, HPV vaccination is recommended in 11-14 year-old girls with a catch-up for girls aged 15-19. The objective of this study was to assess the potential impact of an HPV 6/11/16/18/31/33/45/52/58 nonavalent vaccine on anogenital and oropharyngeal HPV-related diseases in France.Methods : HPV genotype distributions from 6 multicentric retrospective studies (EDiTH I to VI) were analyzed including 516 cases of invasive cervical cancers (ICC), 493 high-grade cervical neoplasias (CIN2/3), 397 low-grade squamous intraepithelial lesions (LSIL), 423 GW, 366 anal cancer and 314 oropharyngeal carcinomas. Low and high estimates of HPV vaccine impact were calculated as follows: low estimate: prevalence of HPV 6/11/16/18/31/33/45/52/58 genotypes alone or in association but excluding presence of another HPV type; high estimate: prevalence of HPV 6/11/16/18/31/33/45/52/58 genotypes alone or in association, possibly in presence of another HPV type.Results : Estimates of potential impact varied from 85% (low estimate) to 92% (high estimate) for ICC, 77% to 90% for CIN2/3, 26% to 56% for LSIL, 69% to 90% for GW, 81% to 93% for anal cancer, and 41% to 44% for oropharyngeal carcinomas. Compared to the quadrivalent vaccine, the proportion of additional cases potentially prevented by the nonavalent vaccine was 9.9%-15.3% for ICC, 24.7%-33.3% for CIN2/3, 12.3%-22.7% for LSIL, 2.1%-5.4% for GW, 8.5%-10.4% for anal cancer, and 0.0%-1.6% for oropharyngeal carcinoma.Conclusions : The nonavalent HPV vaccine showed significant increased potential impact compared to the HPV 6/11/16/18 quadrivalent vaccine for ICC, CIN2/3 and LSIL. Considering a 100% vaccine efficacy and high vaccine coverage, about 90% of ICC, CIN2/3, GW or anal cancer cases could be prevented by a nonavalent HPV vaccine in France

Centre d’études interdisciplinaires des faits religieux – CEIFR

Sossie Andézian, chargée de recherche au CNRS Fondation de lieux de culte : retour sur la notion de lieu saint Ce séminaire, qui faisait suite à un atelier organisé depuis deux ans autour des processus de fondation de lieux de culte, s’est déroulé du 27 novembre au 25 juin, avec la participation de chercheurs et de membres associés du CEIFR ainsi que de collègues d’autres centres de recherche de l’EHESS ou d’autres établissements (Universités Paris-I/Panthéon-Sorbonne et Paris IV/Sorbonne), a..

Un ensemble funéraire de la transition âge du Fer-Antiquité en contexte karstique : la grotte Rochefort à Saint-Pierre-sur-Erve (Mayenne)

Dans le cadre de la fouille programmée de la grotte Rochefort, l’étude préalable des niveaux récents a permis d’identifier de nombreux restes osseux humains disséminés sur la totalité de la surface de la « salle des Troglodytes ». Sans connexions anatomiques et intimement mêlés à des tessons de céramiques au sein d’une unité stratigraphique perturbée, ces os correspondent au démantèlement d’un dépôt funéraire primaire pour lequel une attribution à La Tène finale ou au début de l’Antiquité est avancée. L’article se propose d’établir un inventaire de ces restes osseux et de comprendre le dépôt initial en liaison avec le mobilier céramique et métallique retrouvé, qui devait accompagner les défunts. Nous replacerons cet ensemble dans l’inventaire plus large des sites funéraires gaulois en grotte pour lesquels les données commencent à se préciser.A funerary site from the Iron Age-Antiquity transition period in a karstic context: Rochefort Cave, Saint-Pierre-sur-Erve (Mayenne), in the context of the excavation of the Rochefort Cave, the preliminary study of the recent levels identified numerous human bone remains spread over the whole surface of the “Troglodytes” chamber. Lacking anatomic connections and closely mixed with ceramic shards within a disturbed stratigraphic unit, these bones appear to be the result of the dismantling of a primary funerary deposit for which a final La Tene or early Gallo-Roman date is put forward. This article offers an inventory of these bone remains in order to understand how the initial deposit could be associated with the ceramic and metal assemblage which could have accompanied the dead. This is placed in the wider inventory of Gallic cave funerary sites for which data are becoming more precise

Order recall in verbal short-term memory: The role of semantic networks

In their recent article, Acheson, MacDonald, and Postle (Journal of Experimental Psychology: Learning, Memory, and Cognition 37:44-59, 2011) made an important but controversial suggestion: They hypothesized that (a) semantic information has an effect on order information in short-term memory (STM) and (b) order recall in STM is based on the level of activation of items within the relevant lexico-semantic long-term memory (LTM) network. However, verbal STM research has typically led to the conclusion that factors such as semantic category have a large effect on the number of correctly recalled items, but little or no impact on order recall (Poirier & Saint-Aubin, Quarterly Journal of Experimental Psychology 48A:384-404, 1995; Saint-Aubin, Ouellette, & Poirier, Psychonomic Bulletin & Review 12:171-177, 2005; Tse, Memory 17:874-891, 2009). Moreover, most formal models of short-term order memory currently suggest a separate mechanism for order coding-that is, one that is separate from item representation and not associated with LTM lexico-semantic networks. Both of the experiments reported here tested the predictions that we derived from Acheson et al. The findings show that, as predicted, manipulations aiming to affect the activation of item representations significantly impacted order memory