1,086 research outputs found
L’évaluation des SAMI (système d’apprentissage multimédia interactif) : de la théorie à la pratique
Cet article traite de la mise au point d'une stratégie de collecte de données visant à regrouper et à analyser les facteurs sous-jacents au développement d'une interactivité significative dans des situations d'apprentissage médiatisé. Les auteurs ont conçu un modèle adapté d'analyse axée principalement sur une approche qualitative; ils ont utilisé à cette fin des méthodes intégrant la technique de l'entrevue, l'observation directe et l'analyse de protocoles. Celles-ci ont permis de cerner les facteurs perceptifs, transactionnels, cognitifs, pédagogiques et évaluatifs qui peuvent diriger la prise de décision des concepteurs de systèmes d'apprentissage multimédia interactifs. Des mises à l'essai de ce modèle à l'aide de concepteurs issus des milieux de formation scolaire ont indiqué la pertinence et le raffinement des analyses possibles.This article describes the development of a data collection strategy whose aim is to classify and analyse the factors underlying interaction in mediated learning situations. The authors present a model for analysis that is centred principally on a qualitative approach which integrates an interview technique, direct observation, and protocol analysis. These methods were used to describe perceptual, transactional, cognitive, pedagogical, and evaluative factors that could influence decisions made by those who develop interactive multimedia learning systems. Results of trials using this model by developers who work in training and in school contexts show the possible value and the detail that these analyses offer.Este articulo discute la preparacion de una estrategia de recoleccion de datos que busca reagrupar y analizar los factores subyacentes al desarrollo de una interactividad significativa en situaciones de aprendizaje mediatizado. Los autores han creado un modelo adaptado de anâlisis basado principalmente en un enfoque cualitativo, utilizando para es to métodos que integran la técnica de entrevistas, la observation directa y el anâlisis de protocolos. Estos métodos han permitido distinguir los factores perceptuales, transaccionales, cognos-citivos, pedagogicos y evaluativos que pudieran dirigir la toma de decisiones de los disenadores de sistemas de aprendizaje interactivo multimedios. Ensayos de este modelo con disenadores en ambitos de formation y escolar han indicado la pertinencia y el refinamiento del anâlisis posible.Dieser Artikel befasst sich mit der Aufstellung einer Datenerfassungs-strategie, die bezweckt, die Vorrausetzungen fur die Entwicklung einer signifikanten Interaktion in mediatisierten Lernsituationen zusammenzustellen und zu analysieren. Die Verfasser haben ein hauptsâchlich auf qualitatives Vbrgehen hin konzipiertes Untersuchungsmodell entworfen, wobei sie Methoden benùtzten, die das Interview, die direkte Beobachtung und die Protokollanalyse integrieren. Mit diesen Metiioden konnten die Perzeptions-, Transaktions-und Kognitionsfaktoren, sowie die pâdagogischen und die Beurteilungsfaktoren erfasst werden, die fur die Autoren neuer interaktiver Multimedia-Lernsysteme wichtig sind. Das Modell wurde mit Hilfe von von der Bildung oder Schule her kommenden Autoren erprobt; die Relevanz der Untersuchungen wurde dabei bestâtigt
L’incarcération du père : expérience et besoins des familles
La problématique des pères détenus soulève de nombreuses questions relatives aux rôles et fonctions habituellement assumés par le père, aux différentes étapes qui jalonnent la peine (arrestation, détention, libération) et aux services qui pourraient être offerts aux familles. Dix-neuf pères incarcérés, sept conjointes et deux enfants ont été interviewés sur ces questions. Ils disent n’avoir pu compter que sur le soutien de leur réseau informel (essentiellement, la famille et la belle-famille). Le soutien formel, offert par les différents services ou ressources qui pourraient oeuvrer auprès des familles, est décrit comme lacunaire. C’est au moment de l’arrestation et de celui de la remise en liberté que les besoins d’intervention semblent plus pressants. Lors de l’arrestation, les familles désirent pouvoir bénéficier de renseignements et de conseils sur le déroulement du processus judiciaire et du procès. Durant la détention proprement dite, les répondants souhaitent l’amélioration des lieux réservés aux visites familiales, tel l’aménagement de salles pouvant favoriser les activités parents-enfants, ainsi que l’implantation d’un système de transport offrant plus de facilité. Lors de la réunification familiale, les pères et leurs conjointes ont également dit souhaiter être mieux encadrés par un programme ou une intervention visant spécifiquement les pratiques parentales.The situation of incarcerated fathers raises numerous questions relating to the roles and functions normally assumed by the father in his family, to the different stages marking the sentence (arrest, detention, release), and to the services that could be offered to the families. Nineteen incarcerated fathers, seven spouses, and two children were interviewed on these questions. They report having only received assistance from their informal support network (primarily, the family and the in-laws). Formal support, provided by various services or resources that could work with these families, is described as deficient. The need for support and interventions appears to be most pressing at the time of the arrest and of the release. When the arrest occurs, families would like to receive information and advices about the functioning of the judicial process and the trial. During detention per se, participants wish for the improvement of the reserved family visit spaces, or even the fitting out of a unit favouring parents-children activities, as well as the establishment of a facilitating transport system. Upon family reunification, the fathers and their spouses mentioned their wish to be better supervised through a program or an intervention specifically focused on parenting skills
Carriage of Campylobacter by sows and spread to fattening pigs in farrow-to-finish farms
We carried out a one-year study, in 2008, at 53 farrow-to-finish farms in Brittany, France, to determine the proportion of sows excreting Campylobacter and to determine whether Campylobacter excretion by fattening pigs on these farms was related to transmission from sows. We also determine the genotypes of the Campylobacter isolates
Occurrence and genetic diversity of Salmonella in organic and conventional pig productions in France
The objectives of this study were 1) to assess the occurrence of Salmonella in organic pig production, in comparison with conventional pig production, 2) to evaluate the genetic diversity of strains isolated from these two productions and 3) to estimate the cross-contamination on slaughter line between conventional pig and organic pig.
In one slaughterhouse, 26 organic herds and 31 conventional herds (2 pigs per herd) were sampled for Salmonella detection. Analyses were realized on colon content and swabs of carcass for each pig. Two isolates by positive samples were serotyped and typed by PFGE using XbaI enzyme. All S. Typhimurim and monophasic variant of serovar Typhimurium were subtyped by MLVA.
Prevalence of Salmonella in colon content was higher for organic pigs, 37.9% IC95than for conventional pigs, 32.7% but difference was not significant (p=0.563). Salmonella prevalence was lowest on carcasses and very close between the two productions: 10.7% for organic and 10.3% for conventional.
The 104 isolates were distributed in 7 serovars: Derby (46 isolates), Brandenburg (18), Typhimurium (13), monophasic variant of Typhimurium 4,12:i:- (11) and 4,5,12:i:- (10), Infantis (2) and Mbandaka (2). Sixteen PFGE profiles were obtained: 1 per serovar for serovars Mbandaka, Infantis, and Brandenbrug, 3 for Derby, 4 for Typhimurium and 4 for monophasic variant 4,12:i:-.
Seven PFGE profiles, representing 84% of the isolates, were common between organic and conventional pigs. A major profile gathered 79% of the S. Derby strains. S. Brandenburg strains were also very clonal, all presented the same PFGE profiles whereas they came from 5 different herds. With 20 isolates from 12 carcasses, it has not been possible to show with certainty Salmonella cross-contamination between organic and conventional pigs during the process.
For S. Typhimurium, MLVA gave a better discrimination than PFGE, 8 patterns against 4; particularly for 6 isolates with the same PFGE pattern which was subdivided into 5 MLVA patterns. While on the 21 monophasic isolates, MLVA and PFGE gave similar discrimination (7 patterns with MLVA and 6 with PFGE)
Genetic characterization of Yersinia enterocolitica collected from tonsils of slaughtered pigs
From January to March 2009, detection of pathogenic Yersinia enterocolitica was done from 900 tonsils swabs collected from 45 pig batches in one slaughterhouse. 316 Y. enterocolitica isolates were collected and confirmed as pathogenic biotype by biochemical tests. For this study, these strains were genetically characterized on the basis of their virulence genes and their PFGE profiles. Real Time PCR was used to evaluate the presence of genes ail, myfA, and ystA on the genome and the gene yadA on the pYV plasmid. PFGE analysis using XbaI enzyme was also realised
La réserve extractiviste de Ciriaco : babaçu durable pour les petits producteurs?
L'expérience de développement durable étudiée, la réserve extractiviste de Ciriaco a été implantéedans le municipe de Cidelândia, localisé dans la région dite du Bico do Papagaio, à l'extrême sudouestde l'État du Maranhão. La zone s'insère dans la région écologique de la "Pré-Amazonie"(SEPLAN), qui correspond à une bordure forestière de transition du massif amazonien
Genetic diversity and silencing suppression effects of Rice yellow mottle virus and the P1 protein
<p>Abstract</p> <p>Background</p> <p>PTGS (post-transcriptional gene silencing) is used to counter pathogenic invasions, particularly viruses. In return, many plant viruses produce proteins which suppress silencing directed against their RNA. The diversity of silencing suppression at the species level in natural hosts is unknown.</p> <p>Results</p> <p>We investigated the functional diversity of silencing suppression among isolates of the African RYMV (<it>Rice yellow mottle virus</it>) in rice. The RYMV-P1 protein is responsible for cell-to-cell movement and is a silencing suppressor. Transgenic <it>gus</it>-silencing rice lines were used to investigate intra-specific and serogroup silencing suppression diversity at two different levels: that of the virion and the P1 silencing suppressor protein. Our data provide evidence that silencing suppression is a universal phenomenon for RYMV species. However, we found considerable diversity in their ability to suppress silencing which was not linked to RYMV phylogeny, or pathogenicity. At the level of the silencing suppressor P1 alone, we found similar results to those previously found at the virion level. In addition, we showed that cell-to-cell movement of P1 was crucial for the efficiency of silencing suppression. Mutagenesis of P1 demonstrated a strong link between some amino acids and silencing suppression features with, one on the hand, the conserved amino acids C95 and C64 involved in cell-to-cell movement and the strength of suppression, respectively, and on the other hand, the non conserved F88 was involved in the strength of silencing suppression.</p> <p>Conclusion</p> <p>We demonstrated that intra-species diversity of silencing suppression is highly variable and by mutagenesis of P1 we established the first link between silencing suppression and genetic diversity. These results are potentially important for understanding virus-host interactions.</p
Evaluation fo the colonizing ability on IPEC-J2 cells of the pathogenicity on Caco-2 cells of the 3 major French pig Salmonella serovars
Salmonella enterica subspecies enterica is recognized as the etiological agent of Salmonellosis, a zoonotic disease transmitted in humans through contaminated food. In 2015, Salmonella s. p. was reported as the second bacterial agent responsible of gastro-enteritis in the European Union (EFSA, 2016). Pig consumption is considered as a major source of human Salmonella infections (Bonardi, 2017). Salmonella subspecies can be divided in 1530 serovars based on different epitopes and surfaces antigens. Associations exist between serovars and livestopchk species. In Pigs, in France, Salmonella Typhimurium, Derby and recently the monophasic variant of S. Typhimu-rium (vmST) are the most frequently isolated serovars (Denis et al., 2013; Kerouanton et al., 2013). The presence of monophasic variant of S. Typhimurium is also described in pigs in Europe (Bonardi et al. 2016)
Looking for the vector of the latest discovered geminivirus genus, Capulavirus. [P.48]
Viral metagenomics studies based on virion-associated nucleic acid extraction, sequence-independent amplification and next generation sequencing proved to be effective for discovering three highly divergent geminiviruses in South Africa, France and Finland. Although these geminiviral sequences were isolated from different continents, hemispheres and plant families, including Euphorbia caput-medusae (Euphorbiaceae), Medicago sativa (Fabaceae) and Plantago lanceolata (Plantaginaceae), they were clustered in the same phylogenetic group and were highly divergent from all the sequences classified in the seven established geminivirus genera. Based on sequence relatedness and genome organization, these new highly divergent geminivirus species were provisionally classified in a new geminivirus genus, tentatively named "Capulavirus". To estimate the epidemiological potential of these new geminiviruses but also to confirm their classification according to the criteria defined by the International Committee on Taxonomy of Viruses, including insect vector and host range, further studies were done with two capulaviruses available in our laboratory: Euphorbia caput medusae latent virus (EcmLV) from South Africa (Bernardo et al. 2013) and a capulavirus isolated from alfalfa in France provisionally named Alfalfa leaf curl virus (ALCV) according to the symptoms observed on infected plants. ALCV may cause yield losses because the infected plants exhibited stunting and distorted growth. ALCV was detected in Camargue, Provence Alpes Côte d'Azur, Languedoc Roussillon and Midi-Pyrénées. An infectious clone of EcmLV was prepared and used to determine the host range of EcmLV and test various phloem feeding insects reared in our laboratory, for vector transmission. Potentially infectious clones are presently prepared for ALCV for similar tests. In the meantime, a naturally infected alfalfa plant was transferred to a growth chamber and used as source plant for vector transmission. Potential vectors were also collected from infected alfalfa fields for testing ALCV transmission to alfalfa seedlings prepared in insect proof conditions. (Résumé d'auteur
- …