Rpgrip1 is required for rod outer segment development and ciliary protein trafficking in zebrafish

The authors would like to thank the Royal Society of London, the National Eye Research Centre, the Visual Research Trust, Fight for Sight, the W.H. Ross Foundation, the Rosetrees Trust, and the Glasgow Children’s Hospital Charity for supporting this work. This work was also supported by the Deanship of Scientific Research at King Saud University for funding this research (Research Project) grant number ‘RGP – VPP – 219’.Mutations in the RPGR-interacting protein 1 (RPGRIP1) gene cause recessive Leber congenital amaurosis (LCA), juvenile retinitis pigmentosa (RP) and cone-rod dystrophy. RPGRIP1 interacts with other retinal disease-causing proteins and has been proposed to have a role in ciliary protein transport; however, its function remains elusive. Here, we describe a new zebrafish model carrying a nonsense mutation in the rpgrip1 gene. Rpgrip1homozygous mutants do not form rod outer segments and display mislocalization of rhodopsin, suggesting a role for RPGRIP1 in rhodopsin-bearing vesicle trafficking. Furthermore, Rab8, the key regulator of rhodopsin ciliary trafficking, was mislocalized in photoreceptor cells of rpgrip1 mutants. The degeneration of rod cells is early onset, followed by the death of cone cells. These phenotypes are similar to that observed in LCA and juvenile RP patients. Our data indicate RPGRIP1 is necessary for rod outer segment development through regulating ciliary protein trafficking. The rpgrip1 mutant zebrafish may provide a platform for developing therapeutic treatments for RP patients.Publisher PDFPeer reviewe

Qualitative modelling and analysis of regulations in multi-cellular systems using Petri nets and topological collections

In this paper, we aim at modelling and analyzing the regulation processes in multi-cellular biological systems, in particular tissues. The modelling framework is based on interconnected logical regulatory networks a la Rene Thomas equipped with information about their spatial relationships. The semantics of such models is expressed through colored Petri nets to implement regulation rules, combined with topological collections to implement the spatial information. Some constraints are put on the the representation of spatial information in order to preserve the possibility of an enumerative and exhaustive state space exploration. This paper presents the modelling framework, its semantics, as well as a prototype implementation that allowed preliminary experimentation on some applications.Comment: In Proceedings MeCBIC 2010, arXiv:1011.005

Cyclic indentation test to characterize viscoelastic behavior of polymers

The Oliver & Pharr analysis of indentation data is generally acknowledged and used by research labs and industries to characterize the mechanical behaviour of metals at small scales. It is based on the Sneddon’s contact model of a rigid indenter penetrating an elasto-plastic matter and is perfectly suitable for these materials. However, when the nanoindentation technique is used to study polymer behaviour, there is no general agreement on the procedure and analysis method to use. It is clear that getting the elastic and plastic parameters from the fitting of a single unloading is insufficient to fully characterize the time-dependent behaviour of these materials. The indentation methods applied on polymers are usually inspired by the well-known macroscopic mechanical tests and implemented with the nanoindentation equipment. For instance, a creep test is reproduced through nanoindentation at constant force, revealing a logarithmic behaviour similar to macroscopic one. When small oscillations are superposed on the static nanoindentation loading, a dynamical loss and storage moduli can be calculated by an analogy to the macroscopic DMA technique. The direct analogy between macroscopic static and dynamic behaviour, and microscale contact behaviour might be questionable due to many factors. Nevertheless, these methods are the only procedures available today to access the local mechanical properties of polymers with nanoindentation. In this work, we suggest a new cyclic indentation method and material behaviour analysis inspired by a macroscopic tension fatigue test. Our test consists of up to1200 loading-unloading cycles after an initial holding period at low load to correct for a thermal drift. Each hysteresis loop is analyzed to obtain its area, the secant rigidity and mean (ratcheting) displacement similarly to the area, secant modulus and ratcheting strain characterizing the macroscopic test (see Figure 1). The frequency and load ratio effects on these three parameters are also studied. The cyclic indentation test is performed at two glasses, a titanium alloy and several polymers to make sure that the observed time-dependency is due to the material behaviour and not to the indentation technique itself. The results obtained on a high density polyethylene are discussed and compared with the macroscopic tension fatigue behaviour demonstrated by this material previously [1]. Please click Additional Files below to see the full abstract

BORNE (Dominique), FALAIZE Benoit (dir.), Religions et colonisation. Afrique – Asie – Océanie – Amériques XVIe-XXe siècle

En 2002, dans le rapport remis au ministre de l’Éducation nationale, Régis Debray affirme la nécessité de « rapprocher les démarches pédagogiques et la recherche scientifique », citation proche de la finalité de cet ouvrage : « rassembler et […] discuter les résultats de la recherche et [...] réfléchir simultanément à des traductions scolaires » (« Introduction », p. 12). L’ouvrage qu’ont dirigé Dominique Borne et Benoit Falaize est le résultat de la collaboration de vingt-cinq chercheurs dan..

Las doradas manzanas de la ciencia ficción: Francisco Porrúa, editor de Minotauro

En el marco de los estudios sobre la historia de la edición latinoamericana, esta tesis reconstruye y analiza el catálogo de Ediciones Minotauro, editorial fundada por el hispano-argentino Francisco “Paco” Porrúa en 1955, que a lo largo de cincuenta años tuvo un papel clave en la consolidación del género fantástico en castellano. Porrúa leyó la ciencia ficción norteamericana a través del surrealismo francés; a partir de la evolución de esas lecturas, fundó una versión sofisticada del género y luego, en su propio catálogo, lo disolvió en el mainstream, anticipándose a lo que ocurre a nivel internacional en este nuevo siglo.Facultad de Humanidades y Ciencias de la Educació

Francisco Porrúa, editor de Minotauro: fundación, consolidación y venta de un punto de vista

En nuestros días el nombre de Francisco ‘Paco’ Porrúa está acompañado sin excepción por “el mítico editor de…”, más allá de lo que vaya a continuación: Cien años de soledad, Rayuela, Sudamericana, El Señor de los Anillos, Minotauro, etc. Lo mítico, o legendario, es un calificativo útil en tanto describe diversas características de su trabajo como editor y de sus libros editados: el esfuerzo titánico, la raigambre fantástica, el éxito imposible. Porrúa perteneció al grupo de editores españoles que se trasladaron a Argentina durante la primera mitad del siglo XX; no obstante, a diferencia de sus compatriotas, el caso de Porrúa sucedió una década antes de la Guerra Civil española. Porrúa nació en 1922 en Corcubión, un pueblo costero de Galicia. Su padre, marino mercante y agente marítimo, pidió un destino en tierra, y fue trasladado del lado opuesto del océano Atlántico: Comodoro Rivadavia. En 1931 su madre enfermó, y juntos volvieron a Galicia. Cuatro años después, poco antes de que empezara la Guerra Civil, viajaron de regreso a la Patagonia, hasta su mudanza a Buenos Aires a los dieciocho años para estudiar Filosofía y Letras.Gerhardt, Federico (ed.). Volumen IV. Proyectos editoriales de españoles en Argentina.Facultad de Humanidades y Ciencias de la Educació

El viaje de la ciencia ficción argentina a los confines del espacio interior

Escribía Elvio Gandolfo en el prólogo de una antología de 1978 : “La ciencia ficción argentina no existe”. Hoy, a razón de una producción novedosa, la ciencia ficción argentina está cerca de tener su propia constelación en el firmamento literario, pero en el tiempo transcurrido tras ese prólogo ocurrieron cambios tanto en el género como en la edición que afectan al modo en el que circula esa producción. A lo largo de este trabajo veremos qué tipo de cambios se produjeron y bajo qué circunstancias de publicación, mediante el análisis de las prácticas editoriales pero también a través de la indispensable y a veces relegada lectura de los textos literarios. Asimismo veremos cómo el peritexto, tanto autoral como editorial, configura los géneros y, en muchos casos, incluso posibilita su surgimiento ; por esta razón se les prestará especial interés.Dans la préface à une anthologie publiée en 1978, Elvio Gandolfo écrivait : « La science-fiction argentine n’existe pas ». Aujourd’hui, à la lumière d’une production nouvelle, la science-fiction argentine n’est pas loin d’avoir sa propre constellation dans le firmament littéraire. Dans le temps écoulé depuis l’introduction de Gandolfo, des changements concernant non seulement le genre, mais aussi le monde de l’édition argentine ont affecté les façons dont cette production littéraire circule. Dans cet article, nous verrons quels types de changements se sont produits, et sous quelles circonstances de publication. Nous verrons que le péritexte, auctorial comme éditorial, configure les genres et même, souvent, rend possible leur émergence.In the introduction to a 1978 science fiction anthology, Elvio Gandolfo wrote : “Argentine science fiction does not exist”. Today, Argentine science fiction is close to having its own constellation in the literary firmament. In the time elapsed since Gandolfo’s introduction, changes have taken place in the genre as well as in the Argentine publishing world, that have affected the ways in which that production circulates. In this article, we will try to determine what kinds of changes have occurred in the genre, and in which publishing context. This approach concerns publishing practices but it does not exclude, as it is too often the case, the analysis of literary texts themselves. We will also see how the peritext, authorial and editorial, determines genres and, in many cases, even prompts their emergence