Theoretical and experimental study of electrochemical reactors with three-dimensional bipolar electrodes Gonzalez Perez, Omar; Bisang, Jose Maria A mathematical model to represent three-dimensional bipolar electrodes is proposed taken into account the leakage current. The model is analytically solved when the electrochemical reaction has a mass-transfer control at low overpotentials, which represents a limiting case of the general mathematical treatment. For this simplified situation, expressions are deduced to evaluate the current and potential distribution and to calculate the leakage current. The effect on the leakage current of kinetic, electrochemical and geometric variables, which are lumped into one dimensionless number, is discussed. The influence of the leakage current on the optimal bed depth under limiting current conditions is also analyzed. Likewise, experimental data, using the deposition-dissolution of copper as test reaction, are compared with the theoretical prediction of the general treatment achieving a good agreement between both.

Successful experiment?: on Chile’s experience with territorial use rights in fisheries Orensanz, Jose Maria; Parma, Ana María Chile’s experience with territorial use rights in fi sheries shows their potential for the management of coastal resources, provided some simple safeguards are put in place.

Occurrence of the Tamarix Leafhopper, Opsius stactogalus Fieber (Hemiptera: Cicadellidae), in Argentina Virla, Eduardo Gabriel; Logarzo, Guillermo Alejandro; Paradell, Susana Liria The paleartic tamarix leafhopper,Opsius stactogalusFieber (Hemiptera: Cicadellidae), can reduce the growth of tamarisk due to the aggregate feeding imposed by their populations. The species was mentioned for Argentina in Metcalf´s catalogue (1967) without locality or region reference, and the contributions on Cicadellidae published by many authors after Metcalf omitted this distributional data. Populations of O. stactogalus on Tamarix sp. were found in 12 sites between 28º 48’ to 39º 17’ S and 64º 06’ to 70º 04’ W, located in both the Neotropical and Andean biogeographic regions.

From fresh water to the slope: fish community ecology in the Río de la Plata and the sea beyond; Desde el agua dulce hasta el talud: ecología de comunidades de peces en el Río de la Plata y el mar adyacente Garcia, Mirta Lidia; Jaureguizar, Andrés Javier; Protogino, Lucila Cristina The spatial pattern of fish assemblages and its relationship with factors along an environment gradient, from fresh to marine water environment along the Río de la Plata estuary (36ºS, 56ºW) the shelf and part of the slope, was examined using data from 22 sampling stations. Fish were sampled from all station with an Engel type trawl (200 mm stretched mesh in the wings, 120 mm stretched mesh in the cod ends, 4 m vertical opening and 15 m horizontal aperture) towed at 4 knots for 20 to 30 min per set. Cluster analysis and ordination analysis MDS were used to define spatial distribution of fish assemblages based on fish composition (abundance and biomass). BIO-ENV process was used to estimate assemblage association with depth, temperature and salinity of surface and bottom waters. The results of these analyses showed that the fish community along the riverine-marine gradient was structured in four assemblages: riverine, estuarine, shelf and slope. These assemblages were found to differ significantly in their species composition. Each assemblage was characterized by several common and discriminator species and characterized by differing environmental conditions. Bottom salinity and bottom temperature were the environmental variables most strongly associated with differences in assemblage structure across the various areas. The changes in assemblage structure between areas were gradual, with no sharp boundaries.; Se analizó el patrón espacial de las asociaciones de peces y su relación con los factores ambientales a lo largo del gradiente desde el agua dulce en el Río de la Plata hasta la parte superior del talud. Los peces fueron muestreados en 22 estaciones con una red de arrastre de fondo tipo Engel (200 mm de abertura de malla en las alas, 120 en el copo, 4 m de abertura vertical y 15 m de abertura horizontal) con una velocidad de arrastre de 4 nudos durante 20 a 30 min. Para definir la distribución espacial de las asociaciones de peces basadas en la composición de la ictiofauna (abundancia y biomasa) se aplicó el análisis de agrupamiento jerárquico y el análisis de ordenación MDS y para estimar la relación entre estas asociaciones con la profundidad, la temperatura y la salinidad del agua en la superficie y el fondo, se utilizó el proceso BIOENV. Los resultados obtenidos demuestran que en la comunidad de peces a lo largo de este gradiente riverino marino se pueden establecer cuatro asociaciones: riverina, estuarial, plataforma y talud. Estas asociaciones fueron significativamente diferentes en la composición de especies, cada una de ellas fue caracterizada por varias especies comunes y discriminantes y presentó diferentes condiciones ambientales. Concluimos que la salinidad y temperatura de fondo fueron las variables ambientales determinantes de la estructura de las asociaciones a través de las áreas. El cambio en la estructura entre las áreas fue gradual y con limites flexibles.

Catalog of the Types of Tenebrionidae and Perimylopidae (Insecta, Coleoptera) Deposited at Museo de La Plata (Argentina) Cabrera, Nora Clara; Fernandez, Liliana Alicia; Flores, Gustavo Ernesto; Lattari, Mariano The 224 types of species of Tenebrionidae and Perimylopidae (Coleoptera) housed in the collection of the Entomology Department of Museo de La Plata up until December 2008 were examined and listed; 96 names are recorded, 39 of them (41 percent) are represented by name bearing types (“primary” types). These 224 types belong to 85 species and 9 subespecies of Tenebrionidae assigned to the following subfamilies: Diaperinae (3 species, 3 types), Lagriinae (4 species, 9 types), Pimeliinae (53 species, 1 subspecies, 128 types), Stenochiinae (7 species, 10 types) and Tenebrioninae (18 species, 8 subspecies, 72 types), and 2 types belonging to 2 species of Perimylopidae. Species and subespecies herein treated were described by Berg (23), Burmeister (1), Bruch (1), Fairmaire (8), Flores & Carrara (1), Flores & Roig-Juñent (1), Flores & Vidal (2), Freude (2), Kulzer (27), Molinari (7), Müller (2), Peña (14), Peña & Barría (2), Pic (3), Steinheil (1) and Viana (1). Complete information is given for each type, including reference to original description, and label data. Two lists were added in order to support future research: one for specimens labelled as types but not found in the bibliography and seemingly not published and another for specimens labelled as types but not included in the original series.

GH modulates hepatic epidermal growth factor signaling in the mouse. Gonzalez, Lorena; Díaz, María Eugenia; Miquet, Johanna Gabriela; Sotelo, Ana Isabel; Fernandez, Diego Carlos; Dominici, Fernando Pablo; Bartke, Andrzej; Turyn, Daniel Epidermal growth factor (EGF) is a key regulator of cell survival and proliferation involved in the pathogenesis and progression of different types of cancer. The EGF receptor (EGFR) is activated by binding of the specific ligand but also by transactivation triggered by different growth factors including GH. Chronically, elevated GH levels have been associated with the progression of hepatocellular carcinoma. Considering EGF and GH involvement in cell proliferation and their signaling crosstalk, the objective of the present study was to analyze GH modulatory effects on EGF signaling in liver. For this purpose, GH receptor-knockout (GHR-KO) and GH-overexpressing transgenic mice were used. EGFR content was significantly decreased in GHR-KO mice. Consequently, EGF-induced phosphorylation of EGFR, AKT, ERK1/2, STAT3, and STAT5 was significantly decreased in these mice. In contrast, EGFR content as well as its basal tyrosine phosphorylation was increased in transgenic mice overexpressing GH. However, EGF stimulation caused similar levels of EGFR, AKT, and ERK1/2 phosphorylation in normal and transgenic mice, while EGF induction of STAT3 and STAT5 phosphorylation was inhibited in the transgenic mice. Desensitization of the STATs was related to decreased association of these proteins to the EGFR and increased association between STAT5 and the tyrosine phosphatase SH2-containing phosphatase-2. While GHR knockout is associated with diminished expression of the EGFR and a concomitant decrease in EGF signaling, GH overexpression results in EGFR overexpression with different effects depending on the signaling pathway analyzed: AKT and ERK1/2 pathways are induced by EGF, while STAT3 and STAT5 activation is heterologously desensitized.

A Simple Combinatorial Criterion for Projective Toric Manifolds with Dual Defect Dickenstein, Alicia Marcela; Nill, Benjamin We show that any smooth lattice polytope P with codegree greater or equal than (dim(P) + 3)/2 (or equivalently, with degree smaller than dim(P)/2), defines a dual defective projective toric manifold. This implies that P is Q-normal (in the terminology of [11]) and answers partially an adjunction-theoretic conjecture by BeltramettiSommese (see [5],[4],[11]). Also, it follows from [24] that smooth lattice polytopes with this property are precisely strict Cayley polytopes, which completes the answer in [11] of a question in [1] for smooth polytopes.

Integrón: el coleccionista de genes; Integrons: gene collectors Di Conza, José Alejandro; Gutkind, Gabriel Osvaldo Los integrones son estructuras genéticas que han despertado gran interés, debido a que algunos de ellos vehiculizan genes de resistencia a los antimicrobianos. Están formados por un fragmento que codifica una integrasa (intI) y, a continuación, una secuencia attI a la que se unen los genes en casetes que codifican diferentes mecanismos de resistencia. Dentro de intI, en su extremo 3´, hay una secuencia promotora Pc a partir de la cual se transcriben los casetes de resistencia integrados, ya que estos genes carecen de promotor. Sin embargo, estos casetes presentan una secuencia específica denominada attC, la cual es reconocida por la integrasa que se une, por recombinación, a la secuencia attI del integrón en la orientación adecuada para su expresión. Los integrones se han clasificado según la secuencia de su integrasa, pero en la actualidad se prefiere clasificarlos según su localización. Se habla, en general, de "integrones móviles" para referirse a aquellos asociados a secuencias de inserción, transposones y/o plásmidos conjugativos, los que en su mayoría median mecanismos de resistencia, y de "superintegrones", de localización cromosómica y con grandes arreglos de genes en casetes. Los integrones móviles de clase 1 son los más abundantes en aislamientos clínicos y suelen estar asociados a transposones del subgrupo Tn21, seguidos por los de clase 2, derivados principalmente de Tn7. Estos elementos no son móviles por sí mismos, pero su asociación con elementos que sí lo son facilita su transferencia horizontal, lo que explica su amplia difusión entre las bacterias. Esta revisión intenta recopilar la información disponible acerca de los integrones móviles descritos en Argentina hasta la fecha.; Integrons gained great interest due to their participation in resistance gene recruitment and expression. Their basic structure includes a fragment that encodes an integrase (intI) followed by a recognition sequence (attI) into which they may incorporate gene cassettes (encoding resistance mechanisms). A promoter (Pc) embedded within the integrase gene controls the transcription of integrated resistance markers, as these genes do not have their own promoters. When in cassettes, resistance genes are flanked by specific sequences (attC), which are recognized by the integrase that, by site specific recombination, incorporates them after attI in proper orientation for their expression. In the past, integrons were classified according to their sequence homology; currently they are classified according to their location. In general, they are divided into "mobile" integrons (those associated with insertion sequences, transposons and/or plasmids, being most of them associated with resistance mechanisms), and chromosomally-located "super" integrons with large arrangements of cassette genes. "Mobile" class 1 integrons are the most abundant in clinical isolates and are generally associated with Tn21 subgroup transposons, followed by class 2, derived primarily from Tn7. These elements are not mobile themselves, but their association with mobile platforms that facilitate horizontal transfer, explains their wide distribution among bacteria. This review also attempts to describe the mobile integrons described so far in Argentina.

Reduced cardio-respiratory coupling indicates suppression of vagal activity in healthy relatives of patients with schizophrenia Berger, Sandy; Boettger, Michael Karl; Tancer, Manuel; Guinjoan, Salvador Martín; Yeragani, Vikram K.; Bär, Karl-Jürgen Previous studies have observed reduced vagal modulation in patients with acute schizophrenia and their first-degree relatives, thus suggesting a genetic predisposition. To investigate vagal modulation, we analyzed the coupling between heart rate and breathing as a putative measure of central autonomic function in 19 patients, 19 of their relatives and 19 matched control subjects. The interaction of heart rate and breathing was investigated in all groups applying the non-linear parameter cross-ApEn, indicating the asynchrony between both time series. In addition, measures of the time and frequency domain of heart rate variability (HRV) were obtained. The main finding of our study is a significantly increased cross-ApEn value, indicating reduced central vagal modulation both in relatives and patients suffering from schizophrenia. Non-linear measures of HRV proved to more sensitively differentiate relatives from control subjects. Furthermore, we observed a correlation between psychopathology and breathing, indicating that positive symptoms are associated with a higher degree of regularity in the breathing pattern. Our results suggest that autonomic dysfunction previously described for patients suffering from schizophrenia is also present in first-degree relatives. This might relate to changes of brainstem activity in patients and relatives, and a common genetic background in patients and their family members can be assumed.

Usos y abusos de fármacos en pacientes con deterioro cognitivo; Use and abuse of drugs in cognitive impairment patients Rojas, Galeno; Serrano, Cecilia Mariela; Dillon, Carol; Bartoloni, Leonardo Carlos; Iturry, Mónica Liliana; Allegri, Ricardo Francisco Introducción: El uso irracional de medicamentos para el tratamiento de los trastornos cognitivos puede incrementar los gastos en países en desarrollo. Objetivo: Analizar el patrón de prescripción de los medicamentos relacionados con el tratamiento de los trastornos cognitivos y compararlo con los ingresos económicos. Pacientes: Se evaluaron en forma prospectiva 313 pacientes que consultaron por olvidos al Laboratorio de Memoria del Hospital Municipal Abel Zubizarreta durante el período de un año. Resultados: Para los pacientes la media de ingresos por mes (año 2007) fue 502,81 pesos equivalente a US$ 152. El 41.55% de los pacientes tenía demencia, 15.65% enfermedad psiquiátrica, 15.01% deterioro cognitivo leve y 27.79% eran normales. Los pacientes recibían un promedio de 2.84 fármacos/día, el 20% recibían al menos una droga para los trastornos cognitivos (9.85% memantina, 6.38% donepecilo y el 4% nootrópicos, vasodilatadores cerebrales o antioxidantes), el 39.3% recibían psicofármacos (28.11 % benzodiacepinas y 9.26 % antipsicóticos atípicos). El 12.76% de pacientes con deterioro cognitivo leve estaban tratados con antidemenciales y el 5.74 % de los sujetos normales recibían antidemenciales. El 4% de los pacientes estaban siendo tratados con muestras médicas. Conclusiones: Nuestra muestra evidenció uso irracional de antidemenciales y psicofármacos.; Introduction: Irrational use of drugs for the treatment of cognitive impairment can increase health costs in developing countries. Objective: to analyze the pattern of drug prescription related to the treatment of patients with dementia and to compare them with the income of patients. Patients: 313 community-based outpatients that seeked medical advice for memory problems, in the Memory Center of Zubizarreta General Hospital (Buenos Aires, Argentina), were prospectively assessed during a period of a year. Results. Patients’ mean income was 502.81 “Pesos Argentinos” which is equivalent to US$152 per month (2007). Fourty one point fifty five percent (41.55%) of the patients had dementia, 15.65% psychiatric diseases, 15.01% mild cognitive impairment and 27.79% were normal. Patients received an average of 2.84 drugs/day, 20% of the patients took at least one drug for cognitive impairment (9.85% memantine, 6.38% donepezil and 4% nootropics, cerebral vasodilators or antioxidants), and 39.3% received psychotropic medication (28.11% benzodiazepines and 9.26 % atypical antipsychotics). Twelve point seventy six percent (12.76%) of the patients with mild cognitive impairment were treated with antidementials, 5.74% of normal subjects received antidementials. 4% of patients were exclusively treated with free samples. Conclusion: In our sample irrational degree of using antidemential drugs and psychotropic agents was found.

Las dinámicas de un pánico moral: hechos y percepciones en la construcción de la violencia escolar Miguez, Daniel Pedro El artículo analiza los procesos sociales a partir de los cuales se constituyen las percepciones públicas sobre la violencia en el medio escolar. Partiendo de las teorías de “pánico moral” se muestra cómo estas se constituyen, en parte, por los efectos de procesos que efectivamente han afectado a la escuela produciendo un incremento en los niveles de uso de la fuerza física entre alumnos, pero se argumenta además que la acción de los medios y sus interacciones con las sensibilidades de la sociedad civil, magnifica la incidencia del problema. Por un lado, confundiendo distintos tipos de fenómeno (diversas formas de violencia) como si fueran de la misma índole. Pero, por otro lado, porque a través de la “denuncia” de los niveles de violencia escolar se canaliza una ansiedad más extendida que responde a una mutación genérica de las relaciones intergeneracionales, que se caracteriza por una pérdida de legitimidad de formas tradicionales de autoridad y regulación social y la inexistencia de formas alternativas claramente establecidas y aceptadas. Así la percepción de que la escuela es cada vez más violenta no respondería estrictamente o solamente a posibles incrementos de esta, sino a que en esa denuncia se expresa en realidad un temor más inefable y extendido acerca de la falta de garantías en los procesos de socialización en las nuevas generaciones.

Las estadísticas de los pueblos indígenas: Etnización de los censos de población Otero, Hernán Gustavo El censo nacional de 2001 midió la población indígena, lo que marcó un cambio significativo en las estadísticas de la población argentina. Si bien ello constituye una afirmación de la preexistencia étnica y cultural de los pueblos indígenas y de sus derechos –reconocidos por la última reforma constitucional–, la pertinencia de las categorías étnicas y la posibilidad de alcanzar medidas confiables son objeto de debate…

Building large-scale spatially explicit models to predict the distribution of suitable habitat patches for the Greater rhea (Rhea americana), a near-threatened species Giordano, Paola Florencia; Navarro, Joaquin Luis; Martella, Monica Beatriz We developed large-scale spatially explicit models to predict the distribution of suitable habitat patches for the Greater rhea (Rhea americana), a near-threatened species, in two areas of central Argentina with different land use: a grassland area (ca. 4943 km2) mainly devoted to cattle grazing and an agro-ecosystem area (ca. 4006 km2) mostly used for crop production. The models were developed using logistic regression and were based on current records of Greater rhea occurrence coupled with remote sensing data, including land cover and human presence variables. The habitat suitability maps generated were used to predict the suitable habitat patch structure for wild rhea populations in each area. Fifty-one percent of the total grassland area was suitable for the species, being represented by a single large patch that included 62% of the individual locations. In the agro-ecosystem, only 28% of the total area was suitable, which was distributed among four patches. Seventy percent of rhea observations were in suitable habitat, with all rheas grouped in the largest patch. Conservation efforts for preserving wild rhea populations should be focused on maintaining habitats similar to grasslands, which are less profitable for landowners at present. Consequently, the protection of the pampas grasslands, a key habitat for this species as well as for others with similar habitat requirements, will demand strong conservation actions through the reconciliation of interests between producers and conservationists, since the proportion of croplands is increasing.

La Educación Artística y la política cultural durante la última dictadura militar en Argentina (1976-1983); The Artistic Education and the cultural policy during the last military dictatorship in Argentina (1976-1983) Rodríguez, Laura Graciela El 24 de marzo de 1976 los integrantes de las tres Fuerzas Armadas en Argentina, organizaron el sexto asalto a un gobierno elegido constitucionalmente, al tiempo que se sucedían otros golpes de Estado de similares características en los países del Cono Sur Latinoamericano (Brasil, Paraguay, Chile y Uruguay). En comparación, la última dictadura militar argentina fue la más cruenta de la región2, dejó un saldo de 30 mil “desaparecidos”, entre los que se encontraban cientos de personas vinculadas al ámbito educativo y cultural. En este artículo observaremos otro aspecto de este proceso vinculado a la intervención de los militares y civiles. Analizaremos dos temas relacionados, por un lado, el contenido de la política cultural y por el otro, la persecución que sufrieron los docentes de las escuelas artísticas. Haremos foco en la normativa producida por los encargados de dos dependencias estatales que estaban bajo la órbita del Ministerio de Educación de la provincia más grande del país, Buenos Aires: la Subsecretaría de Cultura y la Dirección de Enseñanza Artística.; The 24 of March of 1976, the members of the Army Force in Argentina, organized the sixth attack against the democratic government, at the same time that happen another dictatorships characteristic in the countries of the Latin American South (Brasil, Chile and Uruguay). In comparison, the last Argentine military dictatorship was most bloody of the region, left a balance of 30 thousand “disappear”, between which were hundreds of tie people to the educative and cultural area. In this article, we will observe another aspect of this process the intervention of the military and civilians. We will analyze two related subjects; on the one hand, the content of the cultural policy and by the other, the persecution that suffered the teachers of the artistic schools. We will make center in the norm produced by the functionaries of two state dependencies that were under the orbit of the Ministry of Education of the greatest province of the country, Buenos Aires: the Undersecretary’s office of Culture and the Direction of Artistic Education.

Biological nitrogen fixation by adesmia bicolor and A. Macrostachya, potential forage species for arid and semi-arid environments Vileta, Dario German; Bianco, Luciana; Grosso, Mónica; Malpassi, Rosana Noemí In South American arid regions cattle feed lacks during winter. Adesmia bicolor and A. macrostachya are promising forage species because of their growth habit and adaptability to dry winters and N poor soils. Information about their biological nitrogen fixation (BNF) efficiencies is needed. The aim of this work is to determine their BNF efficiencies, nodule morpho-anatomy and spatio-temporal distribution, in symbiosis with rhizobia. In a greenhouse, both species were seeded and irrigated with nutritive solution: Without N; With N; and Inoculated seeds with nutritive solution without N. Nodules morpho-anatomy and spatio-temporal distribution; shoot-leaf, root, and nodule dry matter and N content were analyzed. The studied species showed a mean BNF efficiency of ~60%, which is a relatively high efficiency considering that alfalfa shows a 61% efficiency when grown in central Argentina. This attribute is desirable in wild species with forage potential in arid environments.; En regiones áridas de Sudamérica hay escasez de alimento para el ganado durante el invierno. Adesmia bicolor y A. macrostachya son prometedoras como forraje por sus hábitos de crecimiento y adaptabilidad a inviernos secos y suelos pobres en N. Es esencial disponer de información de sus eficiencias de fijación biológica de N (BNF). El objetivo del presente tra-bajo es determinar sus eficiencias de BNF, morfo-anatomía y distribución espacio-temporal de los nódulos en simbiosis con rizobios. En un invernadero, ambas especies fueron sembradas y regadas con solución nutritiva: “Sin N”; “Con N”; y “Sin N-semillas inoculadas”. Se analizaron la morfo-anatomía y distribución espacio-temporal de nódulos, peso seco y contenido de N de tallos-hojas, raíces y nódulos. Las especies mostraron una eficiencia de BNF media de 60%, la cual es alta considerando que alfalfa presenta un 61% cuando crece en Argentina central. Este atributo es deseable en especies silvestres con potencial forrajero en ambientes áridos.

Weak inequalities for maximal functions in Orlicz–Lorentz spaces and applications Levis, Fabián Eduardo Let 00, denote a net of intervals of the form (x-epsilon,x+epsilon) subset [0,alpha). Let f^{epsilon}(x) be any best constant approximation of f in Lambda_{w,phi´} on B(x,epsilon). Weak inequalities for maximal functions associated with {f^{epsilon}(x)}_epsilon, in Orlicz-Lorentz spaces, are proved. As a consequence of these inequalities we obtain a generalization of Lebesgue´s Differentiation Theorem and the pointwise convergence of f^{epsilon}(x) to f(x), as epsilon tends to 0.

Creencias animales: Una propuesta disposicionalista Danon, Laura En el presente trabajo me propongo extender un enfoque disposicionalista de las creencias -propuesto originariamente por Eric Schwitzgebel- al problema de la atribución de estados mentales a animales no-humanos. Más específicamente, procuro defender que, una vez adoptado tal enfoque, es posible construir un argumento por analogía que muestre que ciertas atribuciones de creencias a animales no-humanos son legítimas y justificadas, pese a su carencia de lenguaje. A continuación, defiendo que un caso de tales atribuciones es el de las creencias instrumentales que guían algunas acciones prácticas basadas en un saber-cómo.

The environs of the massive runaway star BD+43 3654 Peri, Cintia Soledad; Benaglia, Paula; Romero, Gustavo Esteban; Martí, Josep The very massive runaway star BD+43° 3654 (O4 If) seems to be related with a bow shock detected by the MSX mission, that would be the result of the interaction of the strong stellar wind with the ambient matter. Shock-accelerated electrons will cool through synchrotron radiation producing a non-thermal radio source, yet never detected in such scenario. While new Very Large Array observations are carried out, we have examined archive data and present here the findings.

Structural analysis of wind-turbine blades by a generalized Timoshenko beam model Otero, Alejandro Daniel; Ponta, Fernando Luis An important aspect in wind-turbine technology nowadays is to reduce the uncertainties related to blade dynamics by the improvement of the quality of numerical simulations of the fluid-structure interaction process. A fundamental step in that direction is the implementation of structural models capable of capturing the complex features of innovative prototype blades, so that they can be tested at realistic full-scale conditions with a reasonable computational cost. To this end, we developed a code based on a modified implementation of the variational-asymptotic beam sectional (VABS) technique proposed by Hodges et al. VABS has the capacity of reducing the geometrical complexity of the blade section into a stiffness matrix for an equivalent beam, allowing accurate modeling of the 3D structure of the blade as a 1D finite-element problem. In this paper, we report some recent results we have obtained by applying our code to full-scale composite laminate wind-turbine blades, analyzing the fundamental vibrational modes and the stress load in normal operational conditions.

Environmental stress upon hepatopancreatic cells of freshwater prawns (Decapoda: Caridea) from the floodplain of Paraná River Collins, Pablo Agustin In order to evaluate the influence of stressed environments on hepatopancreatic cells of freshwater prawns, Macrobachium borellii Nobili, 1896 and Palaemonetes argentinus Nobili 1901, (Crustacea, Decapoda, Palaemonidae) were collected at three different aquatic environments with different relationship to urban development in Argentina. Furthermore the effects of several cypermethryn concentration on hepatopancreatic cell of M. borellii and P. argentinus were evaluated in a laboratory assays. The "N° 1" lake (Santa Fe Argentina) which is more affected by the anthropogenic pressure and "Don Felipe" lake which is still not strongly by human activities were the studied sites from the floodplain of Paraná river. While Alejandra lake was the intermedia effects sites. Different damaged ultrastructures were found in F- and R-cells of prawns in the stressed lake. The predominant features were: disrupted the microvillous border, swelled mitochondria, reduction of endoplasmic reticulum, dyctiosomes, glycoproteins, desnaturalization of vacuole membrane and premature autolysis. Moreover the F-cell number was higher in the environment near to city than in the others sites. Similar effects were observed in the cypermethryn assays. The observations clearly indicate that the ultrastructure of midgut gland in the both palaemonids varies depending on the site from which animals are collected and the biocid presence. So, in this case it can be stated that the hepatopancreas histology of freshwater prawns is a good tool to monitor the impact of a stressed environment upon freshwater prawns.