Quel est l'effet des dépenses publiques d'éducation sur la qualité de l'éducation primaire?

Rapport de rechercheNuméro de référence interne originel : a1.1 g 101

Active mechanics reveal molecular-scale force kinetics in living oocytes

Active diffusion of intracellular components is emerging as an important process in cell biology. This process is mediated by complex assemblies of molecular motors and cytoskeletal filaments that drive force generation in the cytoplasm and facilitate enhanced motion. The kinetics of molecular motors have been precisely characterized in-vitro by single molecule approaches, however, their in-vivo behavior remains elusive. Here, we study the active diffusion of vesicles in mouse oocytes, where this process plays a key role in nuclear positioning during development, and combine an experimental and theoretical framework to extract molecular-scale force kinetics (force, power-stroke, and velocity) of the in-vivo active process. Assuming a single dominant process, we find that the nonequilibrium activity induces rapid kicks of duration $\tau \sim$ 300 $\mu$s resulting in an average force of $F \sim$ 0.4 pN on vesicles in in-vivo oocytes, remarkably similar to the kinetics of in-vitro myosin-V. Our results reveal that measuring in-vivo active fluctuations allows extraction of the molecular-scale activity in agreement with single-molecule studies and demonstrates a mesoscopic framework to access force kinetics.Comment: 20 pages, 4 figures, see ancillary files for Supplementary Materials, * equally contributing author

Plant-based vaccine for livestock : key points to unleash platform translation in developing countries

Ten years ago the first plant-based vaccine was licensed (DowAgrosciences). It was only 20 years after the first report of a recombinant protein obtained through plant transformation technology. Back then, this vaccine was perceived as the first of an unlimited list of innovative products of a flourishing platform. Unexpectedly, since then, no other veterinary product based on plant molecular pharming (PMP) has reached the market. This review will reflect a transdisciplinary view of the status and challenges that the molecular farming platform faces to become a strategic solution for the agroindustrial sector of developing countries. Recent findings Plant-based veterinary vaccines (PBVV) have the potential to give answers to several challenges that animal health presents today. The urgent need to improve livestock productivity, especially in low and middle-income countries (LMIC), and the current concern about the emergence of antimicrobial resistance associated with animal production, demands new products such as inexpensive vaccines and therapeutics. Based on the translational research scheme, certain barriers that could have limited the development into products of many results obtained in the last 15 years were identified. Summary Unquestionably, the development of innovation in LMIC is a key element in the feasibility of the platform. The emergence of PPP between multiple stakeholders as a strategy to overcome the existing disconnection between academia and industry, could enable the conversion of leading vaccine candidates from the stage of proof of concept into prototypes for industry, and thereby foster ‘productization’ in the field of veterinary vaccines.Inst. de PatobiologíaFil: Perez Aguirreburualde, Maria Sol. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patobiología; ArgentinaFil: Petruccelli, Silvana. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; ArgentinaFil: Bravo Almonacid, Fernando Felix. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular; ArgentinaFil: Wigdorovitz, Andrés. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Virología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Blt1 and Mid1 Provide Overlapping Membrane Anchors To Position the Division Plane in Fission Yeast

Spatial control of cytokinesis is essential for proper cell division. The molecular mechanisms that anchor the dynamic assembly and constriction of the cytokinetic ring at the plasma membrane remain unclear. In the fission yeast Schizosaccharomyces pombe, the cytokinetic ring is assembled in the cell middle from cortical node precursors that are positioned by the anillin-like protein Mid1. During mitotic entry, cortical nodes mature and then compact into a contractile ring positioned in the cell middle. The molecular link between Mid1 and medial cortical nodes remains poorly defined. Here we show that Blt1, a previously enig- matic cortical node protein, promotes the robust association of Mid1 with cortical nodes. Blt1 interacts with Mid1 through the RhoGEF Gef2 to stabilize nodes at the cell cortex during the early stages of contractile ring assembly. The Blt1 N terminus is re- quired for localization and function, while the Blt1 C terminus promotes cortical localization by interacting with phospholipids. In cells lacking membrane binding by both Mid1 and Blt1, nodes detach from the cell cortex and generate aberrant cytokinetic rings. We conclude that Blt1 acts as a scaffolding protein for precursors of the cytokinetic ring and that Blt1 and Mid1 provide overlapping membrane anchors for proper division plane positioning

Topography-driven alterations in endothelial cell phenotype and contact guidance

Bioengineering; Biophysics; Cell biology; Biomedical engineering; Regenerative medicine; Directional topography; Endothelial cells; Vascular-like networks; Contact guidance; Vascularizatio

Renaming the pedagogical knowledge: a look from the teaching practice

El presente artículo tiene como propósito comprender e interpretar la relación entre la práctica pedagógica desplegada y el saber pedagógico de profesores nóveles3 durante el periodo de Formación Inicial Docente (FID), saberes que luego son construidos y desplegados en el quehacer profesional de aula. Para recabar la información se realizaron seis grupos focales y once entrevistas en profundidad a profesores egresados de las carreras de la Facultad de Educación de la Universidad Autónoma de Chile, sede Talca. A partir del análisis de contenido en el marco de la Teoría Fundamentada, se obtuvo como resultado algunas categorías relevantes como las siguientes: significado de los procesos reflexivos durante la formación universitaria, rol docente que favorece el desarrollo de competencias lúdicas, y una alta valoración de las prácticas tempranas durante el proceso formativo. Se concluye que la reflexión permite repensar el despliegue profesional, y consecuentemente la construcción del saber pedagógico. Por su parte, las prácticas tempranas se constituyen en una instancia que permite re-mirar los procesos educativos, a objeto de diseñar estrategias de mejora.The purpose of this article is to understand and interpret the relationship between the pedagogical practice deployed and the pedagogical knowledge of novice teachers4 during the period of Basic Teacher Training (BTT), knowledge that is then constructed and deployed in the classroom. To gather information, six focus groups were conducted as well as 11 in-depth interviews with teachers who graduated from the School of Education of the Universidad Autónoma de Chile, Talca. The outcome of data analysis based on Grounded Theory was the emergence of some relevant categories such as: meaning of reflective processes during the undergraduate education; teaching role that benefits the development of recreational skills, and a high appreciation of early practices during the formative process. Conclusion was that the reflection allows to rethink the professional deployment, and consequently the construction of the pedagogical knowledge. In addition, the early teaching practices become a stage that allows novice teachers to re-evaluate the educational processes, in order to design strategies for improvement

Gereja dan Pendidikan Seni Musik Bagi Anak

The purpose of this study is to understand the importance of carrying out music education by the church. This study explains the importance of art education for humans, the life of art in church and the process of art education that has been occurred in church. In particular, this study reminds us that church should not ignore music education in the church in an effort to maintain the church traditions

Construyendo ludicamente un pacto de convivencia para los estudiantes de grado primero-f del colegio Agustiniano ciudad salitre

El presente documento, recoge una propuesta para construir lúdicamente un pacto de convivencia para los estudiantes de grado 1-F del colegio Agustiniano Ciudad Salitre, a través de la misma, se pretende incentivar a los estudiantes a lograr acuerdos y establecer pactos de una manera dinámica, donde se promuevan actitudes, valores, que favorezcan una mejor comunicación entre ellos y puedan ir apropiando formas de participación y manejo autónomo en el reconocimiento de competencias ciudadanas, que aporten en la construcción de una sana convivencia. A partir de un ejercicio de observación, registro y análisis de algunos datos, se desarrollan cuatro (4) talleres con elementos que aportan a la sensibilización y elaboración de un pacto de aula que motiva la participación y compromiso de los estudiantes como integrantes de un grupo que va reconociéndose y estableciendo acuerdos que les permitan ser ejemplo de participación y sana convivencia

Searching for specific binding sites of the secretory glycoproteins of the subcommissural organ

The molecular organization of Reissner's fiber (RF), the structure of its proteins, and the permanent turnover of these proteins are all facts supporting the possibility that RF may perform multiple functions. There is evidence that CSF-soluble RF-glycoproteins may occur under physiological conditions. The present investigation was designed to investigate the probable existence within the CNS of specific binding sites for RF-glycoproteins. Three experimental protocols were used: (1) immunocytochemistry of the CNS of bovine fetuses using anti-idiotypic antibodies, raised against monoclonal antibodies developed against bovine RF-glycoproteins; (2) in vivo binding of the RF glycoproteins, perfusing into the rat CSF 125I-labeled RF-glycoproteins, or grafting SCO into a lateral ventricle of the rat; (3) in vitro binding of unlabeled RF-glycoproteins to rat and bovine choroid plexuses maintained in culture. One of the anti-idiotypic antibody generated by a Mab raised against RF-glycoproteins binds to choroidal cells. Furthermore, binding of RF-glycoproteins to the rat choroid plexus was obtained when: (1) the choroid plexus was cultured in the presence of unlabeled RF-glycoproteins; (2) the concentration of soluble RF-glycoproteins in the CSF was increased by isografting SCOs into a lateral ventricle; (3) radiolabeled glycoproteins were perfused into the ventricular CSF. This evidence suggests that the apical plasma membrane of the ependymal cells of the choroid plexus has specific binding sites for RF-glycoproteins, of unknown functional significance. The radiolabeled RF-glycoproteins perfused into the rat CSF also bound to the paraventricular thalamic nucleus, the floor of the Sylvian aqueduct and of the rostral half of the fourth ventricle, and title meninges of the brain and spinal cord. The labeling of the paraventricular thalamic nucleus points to a functional relationship between this nucleus and the SCO. The possibility that; the SCO may be a component of the circadian timing system is discussed. Microsc. Res. Tech. 52:541-551, 2001. (C) 2001 Wiley-Liss, Inc