Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99


Search Results: 1 - 10 of 202 matches for " Mariel; Dejean "
All listed articles are free for downloading (OA Articles)
Page 1 /202
Display every page Item
Prey Capture Behavior in an Arboreal African Ponerine Ant
Alain Dejean
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0019837
Abstract: I studied the predatory behavior of Platythyrea conradti, an arboreal ponerine ant, whereas most species in this subfamily are ground-dwelling. The workers, which hunt solitarily only around dusk, are able to capture a wide range of prey, including termites and agile, nocturnal insects as well as diurnal insects that are inactive at that moment of the Nyctemeron, resting on tree branches or under leaves. Prey are captured very rapidly, and the antennal palpation used by ground-dwelling ponerine species is reduced to a simple contact; stinging occurs immediately thereafter. The venom has an instant, violent effect as even large prey (up to 30 times the weight of a worker) never struggled after being stung. Only small prey are not stung. Workers retrieve their prey, even large items, singly. To capture termite workers and soldiers defending their nest entrances, ant workers crouch and fold their antennae backward. In their role as guards, the termites face the crouching ants and end up by rolling onto their backs, their legs batting the air. This is likely due to volatile secretions produced by the ants' mandibular gland. The same behavior is used against competing ants, including territorially-dominant arboreal species that retreat further and further away, so that the P. conradti finally drive them from large, sugary food sources.
Rédactions conversationnelles sur papier et sur ordinateur: une étude de cas Collaborative writing on paper and on computer: a case study
Charlotte Dejean
ALSIC : Apprentissage des Langues et Systèmes d'Information et de Communication , 2003, DOI: 10.4000/alsic.2179
Abstract: Très récemment encore, le modèle de l'apprenant seul face à l'ordinateur était dominant car l'ordinateur était considéré avant tout comme un outil favorisant l'individualisation de l'apprentissage. Depuis quelques années, les technologies au service de l'apprentissage sont envisagées comme pouvant faciliter les interactions sociales (enseignant-apprenants et apprenants-apprenants). C'est dans cette perspective que s'est développé, notamment dans le monde anglophone, un domaine de recherche sur les Apprentissages Collaboratifs Assistés par Ordinateur (ACAO). Les situations de travail auxquelles s'intéresse ce domaine sont le travail à deux ou plusieurs face à un même ordinateur et le travail à plusieurs par le biais de l'ordinateur, c'est-à-dire en réseau (local ou Internet). La situation qui fait l'objet de cette étude relève de la première catégorie évoquée; on s'intéresse en effet aux interactions entre deux apprenants de Fran ais Langue étrangère (FLE), rédigeant ensemble un texte avec un même ordinateur. Ces apprenants participent donc à ce que l'on appelle une "rédaction conversationnelle" ou une rédaction collaborative. Until fairly recently, the model of the learner working alone before a computer was prevailing, since the computer was considered as a tool favoring the individualization of the learning process. In the last few years, technologies associated with learning have been considered to be able to facilitate social interactions (teacher-learners and learners-learners). With this in mind, a domain of research concerning Computer Supported Collaborative Learning (CSCL), has been developed, particularly in the English-speaking world. This domain of research is interested in work situations involving two or more people interacting around the same computer, and several people interacting through computers on a networked system (local or Internet). The object of this study relates to the first situation mentioned; we are interested in the interactions between two learners of French as a Foreign Language, writing together a text using the same computer. Thus, these learners are participating in collaborative writing.
Mezcla génica y linajes uniparentales en Esquel (Pcia. de Chubut): Su comparación con otras muestras poblacionales argentinas
Avena,Sergio A; Parolin,M Laura; Boquet,Mariel; Dejean,Cristina B; Postillone,M Bárbara; Alvarez Trentini,Yisela; Di Fabio Rocca,Francisco; Mansilla,Florencia; Jones,Laura; Dugoujon,Jean Michel; Carnese,Francisco Raúl;
BAG. Journal of basic and applied genetics , 2010,
Abstract: in the present study the genetic compositon of esquel, city located in the argentinean andean patagonia, was estimated in a population sample. a total of 59 non-related blood donors from the zonal hospital were included. five eritrocitary systems, gm allotypes, amerindian, european and african mitochondrial haplogroups, and the m3 mutation in y chromosome were analysed. a survey was done to obtain genealogical information about the donors. genetic admixture was estimated employing the admix program. protein markers showed the presence of 46.9% for the indigenous component and 1.9% for the african component. amerindians mitochondrial haplogroups represented a 79.6%, no subsaharian lineage was present. 23% of males analysed exhibited the aboriginal variant m3. this difference in the sex-specifi c genetic contribution would reveal a gender asimetry in the population history. the data were compared to those obtained previously in the buenos aires metropolitan area, bahía blanca and comodoro rivadavia and also with migrants to buenos aires coming from the north and the west from the country. genetic admixture showed higher values for the amerindian contribution in the argentinian northwest followed by esquel, where the subsaharian component was the lowest found. when considering uniparental markers the higher percentages of autoctonal lineages were observed in esquel and the north of the country, although the patagonic village presented the highest paternal native component considering all the samples analysed, probably due to the late incorporation of the patagonian region to the national state, keeping the autoctonal communities for a longer their authonomy.
Funciones ejecutivas: Un estudio de los efectos de la pobreza sobre el desempe?o ejecutivo
Interdisciplinaria , 2010,
Abstract: recent published research on the negative impact of poverty on neurocognitive development has been broader in scope and has analyzed more in depth the issue. infant malnutrition, inadequate medical care, exposure to stress and violence (shore, 1997), weak speech stimulation and scarce organization of the environment are risk factors conditioning self regulation, as assessed in previous research (musso, 2005; ninio, 1980; peralta de mendoza, 1997; wood, bruner & ross, 1976). nevertheless, there is a need for further study of the mechanisms and various ways in which poverty exercises such negative impact. this work describes and analyzes the effects of some of the mechanisms present in poverty which impact on the development of executive functions such as: interference control and planning, at the beginning of schooling. the sample was conformed by 80 children, between 6 and 10 years of age, boys and girls, attending the first grade of general basic education (2005 cohort, in república argentina), at a school included in the national plan of a thousand schools below poverty level. the group deemed at risk by poverty displayed the following indicators: children with high levels of malnutrition, high percentage of students who repeat courses which accounts for the number of older children, high percentage of unemployed parents, and with low levels of schooling. a control group was used that was formed by children attending a city school, not part of the plan of one thousand schools under the poverty line; their parents had finished obligatory or high level education, they were merchants, employees or professionals. the instruments applied were: simon says game (la voie, anderson, fraze & johnson, 1981, see zelazo, 1996) to assess the executive or response control through the use of a rule, the hanoi tower (two rings version) to assess planing, a self report to assess the childrens′ perception of parental styles (mother / father version) (richaud de minzi, 2006), and the
Anteojitos y Billikines, contrato de lectura (1964-1983)
Falabella, Mariel
La Trama de la Comunicación , 2010,
Abstract: [en] Las revistas destinadas al lector infantil son una de las tantas manifestaciones socioculturales donde podemos dar cuenta de los discursos hegemónicos acerca de la infancia. En este sentido, para aportar a la construcción de discursividades sobre la infancia en Argentina, se comparará el “contrato de lectura” propuesto por dos revistas argentinas dirigidas al ni o lector escolarizado (Billiken y Anteojito) considerando de modo puntual el lapso epocal 1964-1983. Dicho período contempla el lanzamiento de Anteojito –en tanto nueva revista– en un mercado de ni os lectores liderado desde 1919 por una revista pionera y tradicional como Billiken. Dicha incorporación en el ecosistema mediático dirigido al lector infantil lleva a interrogarnos sobre las supuestas modificaciones en el tradicional “dispositivo de enunciación” considerando -de modo particular– la difusión de la televisión en el país. Las portadas de las dos revistas nos permitirán detectar y analizar de modo comparativo –desde la producción de los discursos respectivos– las modalidades de construcción de la relación específica que se plantea con el ni o lector. [en] Magazines aimed at the child reader are one of many cultural events where we can account for the hegemonic discourses about childhood. In this regard, to contribute to the construction of discourses on childhood in Argentina, we will compare the "reading contract" proposed by two Argentine magazines aimed at the schooled child reader (Billiken and Anteojito) between 1964-1983. This period includes Anteojito launching in a children's magazine market led since 1919 by Billiken, a pioneer and traditional magazine. This incorporation into the child reader media ecosystem leads to wonder about the alleged changes in the traditional assemblage of enunciation especially considering the spread of television in the country. The covers of both magazines enable us to detect and analyze in a comparative way –from the respective production of discourse– building arrangements of the special relationship with the child reader
Interdisciplinaria , 2010,
Abstract: La bibliografía acerca del impacto negativo de la pobreza sobre el desarrollo neurocognitivo se ha ampliado y profundizado en los últimos a os. Sin embargo, la explicación acerca de las formas y mecanismos a través de los cuales actúa la pobreza, requiere un mayor estudio. En el presente artículo se describen y analizan los efectos de algunos mecanismos de la pobreza sobre el desarrollo de funciones ejecutivas tales como: el control de interferencia y planificación al inicio de la edad escolar. En el a o 2005 se trabajó con una muestra de 80 ni os de ambos sexos, de 6 a 10 a os de edad que eran alumnos de primer a o de la Educación General Básica (EGB), en una escuela incluida en el Plan Nacional de Mil Escuelas Bajo el Nivel de Pobreza. También se trabajó con un grupo control de 40 ni os sin riesgo que asistían a una escuela de nivel socioeconómico medio. Se administraron pruebas para medir el control de interferencia y escalas de observación comportamental y de percepción del vínculo con respecto a cada padre. Se hallaron diferencias significativas en cuanto al desempe o ejecutivo entre ambos grupos. La percepción de control hostil de parte de la madre, del padre y la edad del ni o, resultaron variables predictivas de la capacidad de planificación. Las diferencias significativas halladas en tre los ni os expuestos y no expuestos a la pobreza, son consistentes con una larga serie de estudios e investigaciones acerca de los efectos de esta y especialmente de su duración, sobre el desarrollo físico, neurológico, cognitivo y social del ni o.
Las personas sin hogar en Rosario. Consideraciones sobre los usos del espacio público urbano
Mariel Bufarini
Cultura-Hombre-Sociedad , 2010, DOI: 10.7770/cuhso-v19n1-art309
Abstract: Desde 1998 la ciudad de Rosario (Santa Fe, Argentina) es objeto de políticas ininterrumpidas de planificación estratégica del territorio. De acuerdo a los diagnósticos de los diversos planes implementados hasta el momento, se ha logrado consolidar “una identidad de ciudad con inclusión”. Ahora bien, las desigualdades sociales entre sectores de la población permiten, en principio, poner en cuestión esta característica. En relación a ello es que en el siguiente artículo analizamos los usos del espacio público urbano que realizan las personas sin hogar, los conflictos que sus prácticas cotidianas generan y las disputas de sentido sobre el uso “legítimo” del espacio público. Nuestro interés reside en refl exionar sobre una problemática que genera tensiones en el marco del proyecto de ciudad que se está implementando.
Modalités de collaboration entre étudiants et constitution d'une communauté dans une activité à distance Students' collaborative processes and community building during an online activity
Charlotte Dejean-Thircuir
ALSIC : Apprentissage des Langues et Systèmes d'Information et de Communication , 2008, DOI: 10.4000/alsic.803
Abstract: Cette étude s'inscrit dans le champ de la communication pédagogique médiatisée par ordinateur et s'intéresse aux échanges entre étudiants engagés dans la réalisation d'une tache collaborative, dans le cadre d'un master 2 professionnel de didactique des langues, à distance. L'analyse des interactions d'un groupe d'étudiants, au moyen d'outils issus de la pragmatique linguistique interactionniste et de l'analyse conversationnelle, permet d'identifier certaines pratiques langagières et formes d'activités communicationnelles qui soutiennent le processus collaboratif et favorisent la constitution d'une communauté en ligne. En se focalisant sur l'étude d'un groupe particulièrement collaboratif, il s'agit de mieux comprendre les processus de collaboration afin de proposer des pistes de réflexion pour les concepteurs et tuteurs de ce type d'activité en ligne. This study belongs to the field of computer mediated pedagogical communication and focuses on students' interactions while engaged in a collaborative task as part of a professional master 2 program in online language education. Using a set of analytic tools grounded on a pragmatic and an interactionist framework, the researcher identified some linguistic practices and communicative activities that foster the collaborative process and support the construction of an online community. By focusing on a particularly collaborative group, the researcher had a better understanding of the collaborative processes involved in the completion of such tasks and was able to suggest directions for further reflection to designers and instructors of similar online activities.
Développer des compétences interactionnelles en collaborant à distance
Charlotte Dejean-Thircuir
Revue Internationale des Technologies en Pédagogie Universitaire , 2010,
Abstract: [Fran ais] Cet article vise à montrer de quelles fa ons des étudiants d’un Master 2 professionnel de didactique des langues engagés dans la réalisation d’une tache collaborative à distance sont amenés à mettre en uvre et à développer des compétences interactionnelles et des compétences instrumentales en construisant des schèmes d’utilisation de l’outil de communication qu’est le chat, dans ce contexte particulier. Cette étude s’inscrit dans le champ de la communication pédagogique médiatisée par ordinateur ; l’analyse des interactions verbales entre étudiants s’appuie sur des outils issus du champ de la pragmatique linguistique interactionniste. [English] This article aims at showing the way students use the text chat whilst engaged in a collaborative task with peer students as part of a master degree program in online language education. It focuses on the way participants develop interactional and instrumental skills by creating schemas of use with this communication tool for training purposes. This study belongs to the field of computer mediated pedagogical communication. The analysis of the verbal interactions between students dwells on analytic tools grounded in the pragmatic and interactionist frameworks.
Analyse de l’effet du type de tache sur l’évolution des connaissances à la suite d’un processus d’apprentissage collaboratif
Sabine Pohl,Karine Dejean
Revue Internationale de Pédagogie de l’Enseignement Supérieur , 2009,
Abstract: L’article analyse l’effet du type de tache sur le partage des connaissances à la suite d’un processus d’interaction dans un contexte d’apprentissage collaboratif. Cet apprentissage collaboratif est réalisé dans le cadre d’une formation universitaire. Deux types de taches sont réalisés par les apprenants. Ils se distinguent selon que la solution nécessite ou non la confrontation de points de vue portant sur le champ conceptuel lié à l’apprentissage à réaliser. La méthode de collecte des données consiste en un entretien semi-directif. Les résultats montrent un effet du type de taches sur l’évolution des connaissances partagées des apprenants. This longitudinal research analyses the effect of the type of task on the development of knowledge following an interaction process in a collaborative learning context. The framework for this collaborative learning is a university education. Two types of tasks are provided to the learners. They differ depending on whether or not the solution requires the comparison of points of view on the conceptual scope of what is to be learned. The data are collected through a semi-directive interview. The results show that the type of task has an effect on the development of shared knowledge.
Page 1 /202
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.