Bordes dinámicos sobre el método de Lattice Boltzmann para simulación de superficies de fluidos en tiempo real Garcia Bauza, Cristian Dario; Lazo, Marcos Gonzalo; Boroni, Gustavo Adolfo; Dalponte, Diego David; Clausse, Alejandro Un problema típico en flujos en geometrías complejas son los bordes móviles, como por ejemplo en la simulación de flujo de sangre en arterias o el movimiento de un barco. En este trabajo se presenta una implementación especial en un autómata de Lattice Boltzmann 2D de aguas superficiales con bordes y obstáculos internos móviles. El esquema permite simular en forma flexible escenarios de ondas superficiales producidas por embarcaciones, reflejos en puentes, y otras situaciones de interés en animación.

Environmental risks, demographic dynamic and Life Quality: Argentina at beginning of XXI century Velázquez, Guillermo Ángel In this work we analyze the relationship among: 1) Certain environmental risks: Flood problems, Earthquakes, Tornadoes and Soil degradation, 2) Demographic dynamics (inter census growth and migratory balances) and 3) Grade of Life Level Quality of Argentinian people. We use a Geographical Information System (GIS) in which we have done the digitalization of the respective layers of environmental risks. Following, we examine the information on demographic dynamics. At last, we present a synthetic index of the population’s Life Quality, which was elaborated starting from a combination of weighted indicators of environmental and socioeconomic dimensions (education, health and housing). The next step is to study the demographic behaviour and the grade of well-being of Argentina’s people different segments for each one of the environmental risks. We start from an operation of overlapping of different layers (for example: flood risk, growth rate, migration balance, etc). All previous stepladder let us size and compare the obtained Life Quality Index with Demographic Dynamics according to the degree of affectation of each one of the considered physical-environmental events. Finally we can establish the future scenario by projecting these phenomena impacts into the process of global environmental change.

O resultado do conhecimento no segundo comentário de Boécio à Isagogé de Porfírio Bertelloni, Carlos Francisco Uma pequena parte do corpus textual conhecido como Aristoteles latinus foi chamado pelos medievais de Logica vetus. Esta era constituída pelas Categorias e o Perí hermeneias, de Aristóteles, pela Isagogé de Porfírio e pelos comentários de Boécio às obras de Aristóteles e de Porfírio. Hoje é indiscutível a importância dos comentários neoplatônicos da Antiguidade tardia para a compreensão dos textos de Aristóteles. Dentro desse programa neoplatônico, os comentários deste também contribuíram para essa compreensão. No caso de Boécio produz-se, contudo, um fenômeno paradoxal, porque, apesar de seu neoplatonismo, em seu segundo comentário à Isagogé de Porfírio, Boécio conseguiu formular uma das interpretações mais profundas do pensamento aristotélico concernente ao resultado de nossa atividade cognitiva. No segundo comentário, Boécio procede por três passos: 1) analisa as três perguntas sobre os universais, formuladas por Porfírio; 2) realiza uma aporia do modo pelo qual Porfírio resolve o problema dos universais; e 3) apresenta sua própria posição acerca dos universais, que é diversa da posição de Porfírio.

Producción ovina extensiva en la Patagonia Austral: el caso de la zona centro de Santa Cruz Andrade, Larry Dennys; Bedacarratx, Valeria de Los Ángeles; Alvarez, Roberto El propósito del artículo consiste en analizar la meseta central de Santa Cruz en sus aspectos socioproductivos. El objetivo de la investigación, de la cual este trabajo es una elaboración parcial, se orienta a establecer la viabilidad del modelo vigente en la región -ovino extensivo-, así como las posibilidades de que las prácticas asociativas se constituyan en el eje articulador de un relanzamiento productivo. Aquí presentamos un primer análisis socioeconómico y productivo con la finalidad de definir el escenario en el que actualmente se lleva adelante la producción ovina extensiva. Incluimos una descripción de los nuevos actores que actualmente operan en el centro-norte de la provincia y, especialmente en nuestra área de estudio, destacándose entre ellos las empresas mineras transnacionales.; The intention of the article is to analyze the central plateau of Santa Cruz in its socio-productive aspects. The main aim of the investigation, from which this work is a partial elaboration, is to establish: on the one hand, the viability of the traditional extensive ovine model in the region; on the other hand, the possibilities that the associative practices have to become the articulador axis of a productive relaunching. Here, we present a first socioeconomic and productive analysis in order to define the scene in which, at the moment, the extensive ovine production takes ahead. We include a description of the new actors who, nowadays, operate in the area of study, standing out among them, the transnational mining companies.

La conformación de nuevas teorías sobre el arte latinoamericano en el proceso de crisis epistemológica de la modernidad Serviddio, Luisa Fabiana El Mayo francés y la entrada de los tanques soviéticos a Praga señalaron simbólicamente el año de 1968 como el momento de apogeo de una crisis –política, socioeconómica, culturalque relativizó los principales proyectos occidentales del siglo XX. En el campo del arte latinoamericano en se trató de un momento de transición, en el que se reformularon algunas respuestas en nuevos términos, y se anticiparon desarrollos teóricos posteriores. Los críticos, transformados en teóricos, ubicaron sus reflexiones dentro de una temporalidad predictiva –la futurología de Romero Brest- y prescriptiva –el pensamiento visual independiente de Acha, o la resistencia de Marta Traba-, buscando figurarse hacia adonde iban las prácticas artísticas de la región.

Música y memoria: La representación del detenido-desaparecido en la industria cultural de la Argentina reciente Quiña, Guillermo Martín En el presente trabajo abordamos la problemática de la representación de los detenidos-desaparecidos por la última dictadura militar argentina en un producto mercantil cultural concreto: la música. Se trata de una indagación acerca de las características que dicha representación asume, preguntándonos por diversas especificidades que hacen a la industria cultural en tanto tal, a la música como producción simbólica y a los modos de su inscripción en la historia reciente de una lucha política concreta. ¿Qué relevancia analítica asumen las condiciones materiales de existencia de la obra musical en la representación del detenido-desaparecido? ¿Qué vínculo establece la obra musical con su propia condición de producto social? ¿Cómo indagar la relación inherente a la obra musical en tanto producto artístico y objeto mercantil? Intentamos reflexionar críticamente acerca de diversos aspectos que constituyen la relación entablada entre las mercancías culturales en sentido amplio y musicales en particular, y los sujetos colectivos históricos involucrados, atendiendo al carácter industrial que asumen hoy aquellas. Se trata de una reflexión que pretende abonar a la construcción de un interés analítico sobre las transformaciones del campo musical local en los últimos años por parte de las ciencias sociales.; In this paper we approach the issue of the representation of disappeared and detained people during the last military dictatorship in Argentina in a concrete cultural and merchant product: music. We look for the characteristics that representation assumes, focusing the different specifications of cultural industry, of music as symbolic production and of the modalities of its presence into the recent history of a particular politic struggle. What is the relevance of material conditions of the existence of musical work on disappeared and detained people representation? Which relation does music establish with its own social product condition? How we should ask about the double condition of music, as an art object and a commodity? We try to think critically about diverse aspects which constitute the relation between cultural and musical commodities, on one side, and collective actors involved, on the other. With this reflection we try to contribute to build an analytic interest on recent changes of the local music field by social sciences.

The surface organization of diacylglycerol pyrophosphate and its interaction with phosphatidic acid at the air-water interface Villasuso, Ana Laura; Wilke, Natalia; Maggio, Bruno; Machado, Estela Edelmira Diacylglycerol pyrophosphate (DGPP), a phosphorylated form of phosphatidic acid (PA), gained attention recently due to its role as signaling lipid. However, little is known about its surface organization and potential impact on membrane-mediated function. In this work we investigated the interfacial behavior of Langmuir monolayers formed with pure DGPP and of its mixtures with PA. We found that changes of the subphase pH affect the surface behavior of DGPP. At pH 8, DGPP forms liquid expanded monolayers with a compressibility modulus of about 60 mN m−1 at collapse. On acidic solutions, the compressibility modulus increases to 90 mN m−1 and the average molecular area is smaller. At pH 8, DGPP and its precursor PA form thermodynamically favored topographically homogeneous non-ideal mixtures. The interaction among these lipids leads to a non-ideal diminution of the mean molecular area and consequently, to an increase of the compressibility modulus, with variations of the surface electrostatics. The favorable interaction of PA and DGPP, leading to changes of the film packing suggest that DGPP may act as a structural signal transducer in membrane-mediated cellular processes.

Role of the quorum sensing mechanism in the response of pseudomonas aeruginosa to lethal and sublethal UVA irradiation Costa, Cristina Susana; Pezzoni, Magdalena; Fernández, Rubén O.; Pizarro, Ramón Augusto The role of quorum sensing (QS) in the response of Pseudomonas aeruginosa to UVA radiation was investigated in the PAO1 strain and derivatives defective in the synthesis of the QS signals 3OC12-HSL (lasI strain), C4-HSL (rhlI strain) or both (lasI rhlI strain). Cell viability measurements demonstrated that the double mutant was significantly more sensitive to UVA than single mutants, which in turn showed reduced cell survival with regard to the PAO1 strain. Irradiation under nitrogen atmosphere and chemiluminescence measurements indicated the oxidative nature of the UVA-induced damage. The activity of the antioxidant enzymes catalase and superoxide dismutase was assayed in these strains before and after irradiation, and a strong correlation between catalase levels and UVA sensitivity was observed. When a sublethal UVA dose was applied to PAO1, a growth delay was observed and this mechanism depended on the rhl system. Moreover, low doses of UVA irradiation triplicated the level of C4-HSL in log PAO1 cells. It is concluded that QS is fundamental in the defense against the toxic effects of UVA in P. aeruginosa. The induction of the QS system by UVA independently of cell density could function as an adaptative strategy to withstand this hostile environmental condition.

Supervivencia de Hogna sp. (Araneae: Lycosidae) depredada por Leptodactylus ocellatus Giambelluca, Luis Alberto; Rodríguez, Raúl; Arias, Daniel; Gonzalez, Alda El objetivo del trabajo es dilucidar la supervivencia de arañas Lycosidae depredadas por ranas Leptodactylidae y si existe o no mecanismos de defensa por parte de las arañas dentro del estomago de la rana, como así establecer el tiempo de sobrevida.

Chelation Therapies: A Chemical and Biochemical Perspective Baran, Enrique José Chelation therapy occupies a central place in modern medicine and pharmacology, beacuse continuous studies with laboratory animals and extensive clinical experience demonstrate that accute or chronic intoxications with a variety of metals can be considerable improved by administration of a suitable chelating agent. In this review the chemical characteristics, properties and uses of the most common chelating agents as well as those of some new and very promising agents of this type, are discussed. In the second part of the review the biological and biochemical impact of these agents, as well as their use for the treatment of some selected diseases and disorders, are also analyzed and discussed in detail.

Trophic dynamics of three sympatric anuran species in a soybean agroecosystem from Santa Fe Province, Argentina Peltzer, Paola; Attademo, Andres Maximiliano; Lajmanovich, Rafael Carlos; Junges, Celina Maria; Beltzer, Adolfo Hector; Sanchez, Laura Cecilia The conversion of forests to agroecosystems presents a challenge for biodiversity conservation. In this study, the feeding habits of three species of anurans (Rhinella fernandezae, Odontophrynus americanus and Physalaemus albonotatus) were comparedRhinella fernandezae, Odontophrynus americanus and Physalaemus albonotatus) were compared between a soybean field and a native forest in Santa Fe Province, Argentina. Our dietary assessment is based on 124 individuals (47 R. fernandezae, 45 O. americanus and 32 P. albonotatus). Lepidopteran larvae were the predominant item in anuranR. fernandezae, 45 O. americanus and 32 P. albonotatus). Lepidopteran larvae were the predominant item in anuran diets from the soybean field, whereas collembola, isopods and snails prevailed in the diets from forests. Generally, the three anuran species shifted their diets as prey differs in the two environments, but R. fernandezae and P. albonotatus maintainedR. fernandezae and P. albonotatus maintained a preference for a few prey types. Mean niche overlap in the soybean field was smaller than expected by chance, suggesting that the three anuran species are competing for limited resources. Trophic studies on other native anurans in agroecosystems should be a priority in conservation efforts due to their potential use as natural control agents, as well as for assessing the consequences of the broad conversion of natural forest to agricultural use in our region and throughout the world.

Saer con Aira Arce, Rafael Gerardo El trabajo propone un diálogo y una polémica con algunas afirmaciones que sobre la obra de Saer realiza Sandra Contreras en su libro Las vueltas de César Aira. Contreras arma el contexto literario contra el cual emerge la obra de Aira y postula una correlación entre las obras de Saer y de Piglia como los dos nombres ampliamente consensuados que encarnarían los valores literarios vueltos hegemónicos en esa etapa. Nuestro punto de vista intenta discutir esta correlación afirmando que, por el contrario, el consenso crítico en el que descansa es posible gracias a una falta de profundidad en el análisis que permite una generalización y simplificación que se han vuelto, a esta altura, endoxales, significativamente dentro de la misma crítica saeriana. La desconstrucción del binomio tendría como consecuencia, en última instancia, acercar la obra de Saer a la de Aira, de manera tal de desarticular completamente la oposición que establece y que está en el sustrato de la lectura de Contreras.

Ética y política. Reflexiones en torno a la relación entre ética del discurso y democracia deliberativa Prono, Santiago Nicolas

La teoría de la democracia deliberativa, como la ética del discurso, constituye una derivación teórica del enfoque de la racionalidad discursiva. En este sentido este artículo analiza la relación que se plantea entre ambas teorías. Se trata de una tarea pendiente, porque para algunos de los exponentes de esta teoría ética, ella parece asumir el rol de conducir y guiar de un modo exclusivo las decisiones políticas, lo cual implica una reducción de la Filosofía política al campo de la ética.

Preliminares de la traducción: dos antologías de poesía francesa cruzadas Venturini, Santiago Este trabajo realizará un trabajo comparativo entre dos antologías de poesía francesa publicadas en Argentina durante los último 30 años: "Poetas franceses contemporáneos" (1974), compilada por el poeta Raúl Gustavo Aguirre y "Poesía francesa contemporánea" (1997), preparada por el poeta Jorge Fondebrider. El análisis del dispositivo paratextual (prefacios, introducciones, notas) de cada una de estas publicaciones resaltará la intervención determinante del traductor, que construye un marco de lectura y le asigna valores específicos a los textos que traduce.

Thin films of cubic mesoporous aluminophosphates modified by silicon and manganese Cecowski, Sasa; Tusar, Natasa Novak; Rangus, Mojca; Mali, Gregor; Soler Illia, Galo Juan de Avila Arturo; Kaucic, Venceslav Mesoporous aluminophosphate thin films and xerogels with ordered three-dimensional pore arrangement, modified by silicon or silicon and manganese, were synthesized. Aluminophosphate reaction mixtures were templated with non ionic polymer surfactant Pluronic F127 and deposited as thin layers of precursor solution on Petri dishes for xerogels and on glass substrates for thin films. Surfactant removal was investigated by thermal analysis. Small Angle X-ray Scattering measurements showed that calcined silicoaluminophosphate (SAPO) and manganese silicoaluminophosphate (MnSAPO) thin films have highly ordered mesostructures, which remain stable up to at least 400°C. The mesostructures exhibit cubic symmetry described by an Im3̄m space group. Cubic mesostructure was confirmed also by TEM, SEM and AFM microscopy. Incorporation of silicon and manganese into the aluminophosphate framework was studied by solid-state NMR and X-ray absorption spectroscopy. Silicon-rich domains were detected in calcined SAPO and MnSAPO xerogels and in MnSAPO thin films. The observation of Si(OSi)3(OAl) framework units at the border of such domains suggests that acid sites might be included within silicoaluminophosphate walls. Mn3+ and Mn2+ cations are present in the MnSAPO frameworks of calcined xerogels and thin films in the molar ratio of 40%/60%. Manganese cations are coordinated to four oxygen atoms, suggesting that they are incorporated within the framework and that they can act as framework redox sites.

Characterisation of two South American food and medicinal plants by chemometric methods based on their multielemental composition Cantarelli, Miguel Angel; Pellerano, Roberto Gerardo; del Vitto, Luis Angel; Marchevsky, Eduardo Jorge; Camiña, José Manuel Introduction - The chemometric characterisation of two plants frequently used as food and medicinal species, Achyrocline satureioides and Achyrocline venosa (Asteraceae: Gnaphalieae), was carried out based on their mineral composition. Both species, known by the common name of 'marcelas', are very similar in their morphological features but they have different medicinal and food properties.Objective - To develop multivariate models for the classification of A. satureiodes and A. venosa based on their mineral content.Methodology - The analytic determinations were made by means of inductively coupled plasma optical emission spectrometry from aerial parts of the plants. An internal standard was used to evaluate the accuracy in the sample treatment and the recovery of toxic elements was studied. The multivariate methods used include principal components analysis, cluster analysis and linear discriminant analysis.Results - Classification for both A. satureioides and A. venosa was successful in all cases using only four variables: aluminium, iron, magnesium and sulphur content. The concentrations of the following elements were determined: Al, As, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, La, Mg, Mn, Mo, Na, Ni, P, Pb, S, Sr, Ti, V, Y and Zn.Conclusions - This method is useful to identify both species in raw material in order to detect eventual errors of selection. Copyright © 2010 John Wiley & Sons, Ltd.The characterization of two plants, frequently used as food and medicinal species from South America, Achyrocline satureioides and Achyrocline venosa (Asteraceae:Gnaphalieae), was carried out based on their multielemental composition. Twenty five elements, including toxic elements, were analyzed by means of inductively coupled plasma optical emission spectrometry (ICP-OES) from aerial parts of the plants. Recovery of toxic elements was study. For characterization, the multivariate methods used include Principal Components Analysis, Cluster Analysis and Linear Discriminant Analysis.

Low-dose radiation employed in diagnostic imaging causes genetic effects in cultured cells Ponzinibbio, Maria Virginia; Crudeli, Cintia; Peral Garcia, Pilar; Seoane, Analia Isabel Background: Exposure to environmental, diagnostic, and occupational sources of radiation frequently involves low doses. Although these doses have no immediately noticeable impact on human health there is great interest in their long-term biological effects. Purpose: To assess immediate and time-delayed DNA damage in two cell lines exposed to low doses of ionizing radiation by using the comet assay and micronucleus test, and to compare these two techniques in the analysis of low-dose induced genotoxicity. Material and Methods: CHO and MRC-5 cells were exposed to 50 milliSievert (mSv) of ionizing radiation and assayed immediately after irradiation and at 16 or 12 passages post-irradiation, respectively. Comet assay and micronucleus test were employed. Results: The comet assay values observed in 50 mSv-treated cells were significantly higher than in the control group for both sample times and cell lines (P < 0.001). Micronuclei frequencies were higher in treated cells than in the control group (P < 0.01, CHO cells passage 16; P < 0.05, MRC-5 cells immediately after exposure; P < 0.01 MRC-5 cells passage 12). Correlation analysis between the two techniques was statistically significant (correlation coefficient 0.82, P < 0.05 and correlation coefficient 0.86, P < 0.05 for CHO and MRC-5 cells, respectively). Cells scored at passages 12 or 16 showed more damage than those scored immediately after exposure in both cell lines (no statistically significant differences). Conclusion: Cytomolecular and cytogenetic damage was observed in cells exposed to very low doses of X-rays and their progeny. A single low dose of ionizing radiation was sufficient to induce such response, indicating that mammalian cells are exquisitely sensitive to it. Comet and micronucleus assays are sensitive enough to assess this damage, although the former seems to be more efficient.

Metáforas en el discurso periodístico Romano, María Belén La metáfora es un recurso lingüístico presente en variados discursos sociales: literario, periodístico, pedagógico, humorístico, etc. La función que cumple en todos ellos no es siempre la misma: en algunos predomina su función estética, en otros explicativa, en otros, persuasiva y polémica. Este trabajo analiza los modos cómo se utiliza la metáfora en el discurso periodístico como vehículo para la formación de representaciones sociales y la transmisión de ideologías que responden a determinados intereses corporativos. Consideramos este tropo desde la Pragmática, especialmente tenemos en cuenta los aportes de Grice (1975) y de Reyes (1998). El corpus está formado por textos periodísticos del diario La Nación que categorizan el gobierno de Néstor Kirchner. Nuestro análisis permite reforzar la idea de la importante función de la prensa en las sociedades democráticas modernas como productora y reproductora de representaciones sociales y como actor político que ejerce poder en y por el discurso.

PM IRRAS spectroelectrochemistry of layer-by-layer self-assembled polyelectrolyte multilayers Tagliazucchi, Mario Eugenio; Méndez de Leo, Lucila Paula; Cadranel, Alejandro; Baraldo Victorica, Luis Mario; Volker, Edgar; Bonazzola, Cecilia; Calvo, Ernesto Julio; Zamlynny, Vlad In situ polarization modulation infrared reflection absorption spectroscopy (PM IRRAS) has been used to study layer-by-layer self-assembled films made of a novel redox polymer bearing an osmium pentacyano pyridine complex (PAH-OsCN) and polyacrylic acid at different electrode potentials and solution compositions. PM IRRAS provides information on the oxidation state of the osmium complex, the fraction of protonated carboxylates and the content of IR-active counterions (such as nitrate) as well as water content (hydratation of the multilayer). It has an advantage over SNIFTIRS because it measures the absolute IR-signal arising from the molecular species at the interface rather than its variation with respect to a reference state. For instance, we show that only a fraction of the total number of redox sites responds to changes in the electrode potential as expected from the Nernst equation. The remaining sites are trapped in the Os(II) or Os(III) states and can only be oxidized/reduced by chemical agents in solution. We also present spectroscopic evidence that nitrate ions enter into the film during oxidation and leave during reduction. The number of these anions involved in the first process is larger than that participating in the latter and hence nitrate accumulates within the film. This finding is analyzed in terms of two possible mechanisms. © 2009 Elsevier B.V. All rights reserved.

Intra- and interspecific divergence in the nuclear sequences of the clock gene period in species of the Drosophila buzzatii cluster; Divergencia inter y intraespecifica en las secuencias nucleares del gene period en las especies del “cluster”Drosophila buzzatii Franco, Fernando Faria; Silva Bernardi, Erica Cristina Carvalho; Sene, Fabio Melo; Hasson, Esteban Ruben; Manfrin, Maura Helena We have measured nucleotide variation in the CLOCK/CYCLE heterodimer inhibition domain (CCID) of the clock X-linked gene period in seven species belonging to the Drosophila buzzatii cluster, namely D. buzzatii, Drosophila koepferae, Drosophila antonietae, Drosophila serido, Drosophila gouveai, Drosophila seriema and Drosophila borborema. We detected that the purifying selection is the main force driving the sequence evolution in period, in agreement with the important role of CCID in clock machinery. Our survey revealed that period provides valuable phylogenetic information that allowed to resolve phylogenetic relationships among D. gouveai, D. borborema and D. seriema, which composed a polytomic clade in preliminary studies. The analysis of patterns of intraspecific variation revealed two different lineages of period in D. koepferae, probably reflecting introgressive hybridization from D. buzzatii, in concordance with previous molecular data.