Aislamiento y caracterización de una sustancia producida por macrófagos con actividad quimiotáctica para linfocitos [por] Ricardo Alberto Gómez Flores

Tesis (Maestria en Ciencias con especialidad en Inmunobio logía). U.A.N.L.

The Conformist by Bernardo Bertolucci: Alberto Moravia + Plato against fascism

Why Bernardo Bertolucci, when adapting as a film Alberto Moravia’s novel Il conformista, introduced into its homonymous The Conformist the Platonic image of the cave? The article is to give an answer to this question by analysing Moravia’s work in search of “cave images”, which would justify Bertolucci’s decision.

El conformista de Bernardo Bertolucci: Alberto Moravia + Platón contra el fascismo

[spa] ¿Por qué Bernardo Bertolucci, al adaptar cinematográficamente la novela de Alberto Moravia Il conformista, introdujo en The Conformist la imagen platónica de la caverna? Este artículo preende dar respuesta a esta pregunta mediante el análisis de una parte considerable de la obra de Moravia.

El conformista de Bernardo Bertolucci: Alberto Moravia + Plató contra el feixisme

[cat] Per què Bernardo Bertolucci, en fer l’adaptació cinematogràfica de la novel·la d’Alberto Moravia Il conformista, introduí a The Conformist la imatge platònica de la caverna? Hom pretén donar resposta a aquesta pregunta mitjançant l’anàlisi de bona part de l’obra de Moravia.

Impacto de la graduación del SPG drogas para la exportación colombiana de flores hacia la Unión Europea

Analizar el ámbito de la exportación colombiana de flores hacia la Unión Europea, tomando como países de referencia a Reino Unido, España y Holanda, y aplicando los reglamentos, las acciones y las decisiones recientes sobre el SPG Drogas

La construcción social de lo visual: estudio de caso en la visión de la virgen de Piendamó en 1971 y su concreción estética en el santuario

Este trabajo responde a la iniciativa de referir el conocimiento académico adquirido al lugar de origen, de éste modo llevo a cabo un análisis enfocado hacia el papel de la construcción social de lo visual a partir de un elemento identitario relevante para el pueblo colombiano del cual provengo: La visión que tuvo una niña mestiza de once años, de la virgen en Piendamó, Cauca, Colombia en 1971. La reflexión parte del supuesto de que la aparición de la virgen responde a una construcción social, cuyo repositorio visual es la aparición de la virgen y luego su concreción estética en el santuario; busco explorar la aparición como respuesta a una serie de fenómenos que mantenían en tensión el campo social, los cuales se relacionan directamente con: 1. El origen del pueblo que le otorga la condición de bárbaro en relación a su Otro civilizado fundado en el marco de la encomienda española 2. La aparición de la virgen como mecanismo de tensión cultural 3. Producciones o disputas en torno a la aparición y su importancia para la comunidad. Esta propuesta se torna relevante en tanto hay un desplazamiento del análisis de lo visual como objeto, hacia las ideas de las cuales es repositorio, esto es hacia la forma en que lo visual es construido a la vez que construye el campo social de las relaciones. La aparición de la virgen es un dispositivo que permite leer mediante los estudios visuales la naturalización de los fenómenos culturales y los significados que perpetua, orientando el análisis hacia los significados reprimidos en ese proceso naturalizador. El marco de fuentes que componen ésta propuesta consisten en: Entrevistas realizadas en campo, observación y análisis del santuario, revisión, análisis y selección de producción mediática, artística y académica, todo ello a la luz de José Luís Brea, Mieka Bal, Homi Bhabha, Bolívar Echeverría, Alberto Flores Galindo, Michel Foucault, Judith Buttler, Sergei Gruzinski, Enrique Dussel entre otros.

Nd-Sr isotopes, diatom and biogenic opal content of Pliocene sediments from IODP Site 318-U1361

Warm intervals within the Pliocene epoch (5.33-2.58 million years ago) were characterized by global temperatures comparable to those predicted for the end of this century (Haywood and Valdes, doi:10.1016/S0012-821X(03)00685-X) and atmospheric CO2 concentrations similar to today (Seki et al., 2010, doi:10.1016/j.epsl.2010.01.037; Bartoli et al., 2011, doi:10.1029/2010PA002055; Pagani et al., 2010, doi:10.1038/ngeo724). Estimates for global sea level highstands during these times (Miller et al., 2012, doi:10.1130/G32869.1) imply possible retreat of the East Antarctic ice sheet, but ice-proximal evidence from the Antarctic margin is scarce. Here we present new data from Pliocene marine sediments recovered offshore of Adélie Land, East Antarctica, that reveal dynamic behaviour of the East Antarctic ice sheet in the vicinity of the low-lying Wilkes Subglacial Basin during times of past climatic warmth. Sedimentary sequences deposited between 5.3 and 3.3 million years ago indicate increases in Southern Ocean surface water productivity, associated with elevated circum-Antarctic temperatures. The geochemical provenance of detrital material deposited during these warm intervals suggests active erosion of continental bedrock from within the Wilkes Subglacial Basin, an area today buried beneath the East Antarctic ice sheet. We interpret this erosion to be associated with retreat of the ice sheet margin several hundreds of kilometres inland and conclude that the East Antarctic ice sheet was sensitive to climatic warmth during the Pliocene.

Abundance of sedentary consumers and sessile organisms along the wave exposure gradient of subtropical rocky shores of the south-west Atlantic

Sedentary consumers play an important role on populations of prey and, hence, their patterns of abundance, distribution and coexistence on shores are important to evaluate their potential influence on ecosystem dynamics. Here, we aimed to describe their spatio-temporal distribution and abundance in relation to wave exposure in the intertidal rocky shores of the south-west Atlantic to provide a basis for further understanding of ecological processes in this system. The abundance and composition of the functional groups of sessile organisms and sedentary consumers were taken by sampling the intertidal of sheltered and moderately exposed shores during a period of one year. The sublittoral fringe of sheltered areas was dominated by macroalgae, while the low midlittoral was dominated by bare rock and barnacles. In contrast, filter-feeding animals prevailed at exposed shores, probably explaining the higher abundance of the predator Stramonita haemastoma at these locations. Limpets were more abundant at the midlittoral zone of all shores while sea urchins were exclusively found at the sublittoral fringe of moderately exposed shores, therefore, adding grazing pressure on these areas. The results showed patterns of coexistence, distribution and abundance of those organisms in this subtropical area, presumably as a result of wave action, competition and prey availability. It also brought insights on the influence of top-down and bottom-up processes in this area.

Source populations in coastal crabs: parameters affecting egg production

Benthic marine invertebrates may form metapopulations connected via propagule dispersal. Conservation efforts often target potential source coastlines to indirectly benefit areas depending on allochthonous offspring production. Besides population density, adult size structure, sex ratio, brooding frequency and the proportion of breeding individuals may significantly influence the reproductive output of benthic populations, but these effects have seldom been tested. We used rocky shore crabs to assess the spatial variability of such parameters at relevant scales for conservation purposes and to test their consistency over 2 consecutive years; we then used the data to address whether bottom-up processes or biological interactions might explain the patterns observed. We decomposed egg production rates into their components for the 2 most abundant brachyuran species inhabiting the intertidal rocky habitat. Adult density and brooding frequency varied consistently among shores for both species and largely explained the overall spatial trends of egg production. Temporally consistent patterns also included among-shore differences in the size of ovigerous females of the grapsid Pachygrapsus transversus and between-bay differences in the fecundity of the spider crab Epialtus brasiliensis. Sex ratio was remarkably constant in both. We found no positive or negative correlations between adult density and brooding frequency to support either the existence of a component Allee effect (lack of mate encounters) or an effect of intra-specific competition. Likewise, shore-specific potential growth in P. transversus does not negatively correlate with frequency of ovigerous individuals, as would be expected under a critical balance between these 2 processes. The patterns observed suggest that bottom-up drivers may best explain spatial trends in the reproductive output of these species.

Effect of crab size and habitat type on the locomotory activity of juvenile shore crabs, Carcinus maenas

Post-settlement processes are a major focus in the study of the dynamics of marine populations and communities. Post-settlement movement of juveniles is an important, but often ignored, process which affects local predator-prey and competitive interactions. We used benthic suction sampling and pitfall traps to examine density and locomotory activity of Carcinus maenas juveniles in different intertidal habitat types in the Rio Mira Estuary, Portugal, to better understand intra-specific interactions in a system where density-dependent processes are known to regulate population dynamics. As expected, significantly higher densities of juvenile shore crabs were found from bare mud compared to densely vegetated habitats. At the time of sampling, small and intermediate stages together outnumbered by far the larger juveniles. Conversely, larger crabs were much more frequent than smaller ones in traps. A locomotory index (LI), i.e. the ratio between crab catch in pitfall traps and their density within their moving range, is proposed as a measure of movement. LI analyses indicated that: (1) movement is an order of magnitude higher in large than small juveniles and much higher in sparse than dense vegetation cover; (2) activity of small juveniles is mostly crepuscular, regardless of vegetation cover; and (3) movement of large juveniles is very limited in dense Zostera patches, but very high in sparsely vegetated areas, during the day and night. These results suggest that small juveniles are relatively protected under dense vegetation cover due to lower mobility of larger crabs, and provide evidence of temporal segregation of activity windows between juvenile crabs of different sizes, which may be a key mechanism to reduce cannibalism and therefore increase the carrying capacity of nursery habitats. (C) 2008 Elsevier Ltd. All rights reserved.