The jamming constant of uniform random graphs Bermolen, Paola; Jonckheere, Matthieu Thimothy Samson; Moyal, Pascal By constructing jointly a random graph and an associated exploration process, we define the dynamics of a “parking process” on a class of uniform random graphs as a measure-valued Markov process, representing the empirical degree distribution of non-explored nodes. We then establish a functional law of large numbers for this process as the number of vertices grows to infinity, allowing us to assess the jamming constant of the considered random graphs, i.e. the size of the maximal independent set discovered by the exploration algorithm. This technique, which can be applied to any uniform random graph with a given–possibly unbounded–degree distribution, can be seen as a generalization in the space of measures, of the differential equation method introduced by Wormald.

Algoritmos de punto de cambio aplicados a la detección de estructuras vorticosas en flujos turbulentos; Change point algorithms applied to the detection of vortex structures in turbulent flows Marañon Di Leo, Julio; Calandra, M. V.; Delnero, Juan Sebastian En este trabajo se presenta el análisis de la aplicación del modelo de un algoritmo de punto de cambio (Change Point Model, CPM), basado en tests no paramétricos, para la detección de estructuras turbulentas en un flujo de aire. Se busca detectar los vórtices generados en la estela de un perfil aerodinámico dotado de un dispositivo de control pasivo de flujo (mini flap de Gurney) ubicado en el borde de fuga. De la muestra de datos obtenida se analiza la aplicación de modelos CPM, con el fin de determinar los posibles cambios de la fluctuación de la velocidad sensada, comparando los resultados con análisis tradicionales. El objetivo principal del estudio es el de detectar las frecuencias características de las estructuras turbulentas inmersas en el campo del flujo. De los resultados obtenidos se desprende que el modelo CPM basado en el test de Cramer-von Mises (CPM-CvM) presenta una buena concordancia con las detecciones esperadas (diferencias menores al 9,5%), mostrando ser una herramienta alternativa para el análisis de estos tipos de flujo en tiempo real. Este trabajo muestra, finalmente, una nueva aplicación para CPM en la detección de cambios en señales aleatorias dependientes del tiempo que tienen una distribución, a priori, desconocida.; The present work shows the application of a change point model (CPM) algorithm, based on non-parametric tests, to turbulent structures detection in an airflow. It seeks to detect the vortices generated in the wake of an airfoil, equipped with a passive flow control device (Gurney mini flap) in its trailing edge. By applying CPM models to the sample data, this paper seeks to determine the possible changes to the velocity fluctuations and compare the model's effectiveness to traditional methods. The main objective of this study is to detect the characteristic frequencies of the turbulent structures immersed in the airflow. The results show that the CPM methodology, based on the Cramer- von Mises (CPM-CvM) test, produces results that coincide with values predicted by traditional methods (less than 9.5% of mismatch), validating its use as a real time alternative tool for the analysis of these types of flows. Finally, this work shows a new application of CPM for detecting changes in a time-dependent random signal, which has an a priori unknown distribution.

Inoculation with Azospirillum sp. and Herbaspirillum sp. Bacteria Increases the Tolerance of Maize to Drought Stress Curá, José Alfredo; Franz, Diego Reinaldo; Filosofía, Julián Ezequiel; Balestrasse, Karina Beatriz; Burgueño, Lautaro Exequiel Stress drought is an important abiotic factor that leads to immense losses in crop yields around the world. Strategies are urgently needed to help plants adapt to drought in order to mitigate crop losses. Here we investigated the bioprotective effects of inoculating corn grown under drought conditions with two types of plant growth-promoting rhizobacteria (PGPR), A. brasilense, strain SP-7, and H. seropedicae, strain Z-152. Plants inoculated with the bacteria were grown in a greenhouse with perlite as a substrate. Two hydric conditions were tested: normal well-watered conditions and drought conditions. Compared to control non-inoculated plants, those that were inoculated with PGPR bacteria showed a higher tolerance to the negative effects of water stress in drought conditions, with higher biomass production; higher carbon, nitrogen, and chlorophyll levels; and lower levels of abscisic acid and ethylene, which are plant hormones that affect the stress response. The oxidative stress levels of these plants were similar to those of non-inoculated plants grown in well-watered conditions, showing fewer injuries to the cell membrane. We also noted higher relative water content in the vegetal tissue and better osmoregulation in drought conditions in inoculated plants, as reflected by significantly lower proline content. Finally, we observed lower gene expression of ZmVP14 in the inoculated plants; notably, ZmVP14 is involved in the biosynthesis of abscisic acid. Taken together, these results demonstrate that these bacteria could be used to help plants cope with the negative effects of drought stress conditions.

Hybrid process for the purification of water contaminated with nitrites: Ion exchange plus catalytic reduction Mendow, Gustavo; Grosso, César L.; Sánchez, Agustina; Querini, Carlos Alberto Water polluted with nitrites represents a big risk to human health. In this work, palladium supported on macroporous anionic exchange resin was used in the catalytic nitrite reduction. This process is compared with the traditional ion exchange procedure using the same catalytic resin. Both, the resin and the catalyst behaviour were evaluated in a fix-bed reactor, feeding water containing nitrites and other competitor ions, such as sulphate, bicarbonate, and chlorides, and adjusting the pH with carbon dioxide. When feeding water containing only nitrites, it was observed that the catalytic reduction makes it possible to treat 55% more water than when using the ion exchange process, at the same level of nitrites elimination. Moreover, in steady state it was possible to obtain a nitrite conversion to nitrogen of 54% with high selectivity, obtaining an ammonium concentration lower than 0.2 mg/L. In the case of having other ions present in the system, both the conversion and the selectivity decreased. A regeneration strategy is also developed, using a very low hydrogen flow rate at atmospheric pressure and room temperature. This treatment leads to the reduction of more than 99% of the nitrites present in the contaminated water. The catalyst was used in several consecutive cycles maintaining a very good performance, even in the presence of competitor ions. The process was scaled up to a pilot level obtaining identical results.

Wnt/β-catenin pathway in the prefrontal cortex is required for cocaine-induced neuroadaptations Cuesta, Santiago; Severin, María Julia; Batuecas, Jorgelina; Rosso, Silvana Beatriz; Pacchioni, Alejandra Maria Behavioral sensitization is a progressive and enduring enhancement of the motor stimulant effects elicited by repeated administration of drugs of abuse. It can be divided into two distinct temporal and anatomical domains, termed initiation and expression, which are characterized by specific molecular and neurochemical changes. This study examines the role of the Wnt canonical pathway mediating the induction of cocaine sensitization. We found that β-catenin levels in the prefrontal cortex (PFC), amygdala (Amyg) and dorsal striatum (CPu) are decreased in animals that show sensitization. Accordingly, GSK3β activity levels are increased in the same areas. Moreover, β-catenin levels in nuclear fraction, mRNA expression of Axin2 and Wnt7b are decreased in the PFC of sensitized animals. Then, in order to demonstrate that changes in the PFC are crucial for initiation of sensitization, we either rescue β-catenin levels with a systemic treatment of a GSK3β inhibitor (Lithium Chloride) or inhibit Wnt/β-catenin pathway with an intracerebral infusion of Sulindac before each cocaine injection. As expected, rescuing β-catenin levels in the PFC as well as CPu and Amyg blocks cocaine-induced sensitization, while decreasing β-catenin levels exclusively in the PFC exacerbates it. Therefore, our results demonstrate a new role for the Wnt/β-catenin pathway as a required neuroadaptation in inducing behavioral sensitization.

Higgsino-like dark matter from sneutrino late decays Medina, Anibal Damian We consider Higgsino-like dark matter (DM) in the Minimal Supersymmetric Standard Model (MSSM) with additional right-handed neutrino chiral superfields, and propose a new non-thermal way of generating the right amount of relic DM via sneutrino late decays. Due to the large DM annihilation cross-section, decays must occur at lower temperatures than the freeze-out temperature Td≪TF,χ˜1 0∼μ/25, implying a mostly right-handed lightest sneutrino with very small Yukawa interactions. In that context, the right amount of Higgsino-like DM relic density can be accounted for if sneutrinos are produced via thermal freeze-in in the early Universe.

La tormentosa relación entre las grasas y el desarrollo de la diabetes mellitus de tipo 2: actualizado: parte 1 Costa Gil, José Esteban; Spinedi, Eduardo Julio En esta parte de la revisión se describe la relación funcional entre el metabolismo de los lípidos y los hidratos de carbono y su interdependencia, desde el ciclo glucosa-ácido grasos y la hipótesis portal de la insulinorresistencia a los nuevos conocimientos sobre los adipocitos marrones y beiges, con énfasis en el normal funcionamiento de un patrón endocrino cuya disfunción es clave en la fisiopatología de la DMT2 y la obesidad. Se discute la ectopia o el asiento de grasa en el tejido magro por incapacidad del tejido adiposo para seguir acopiando lípidos y la actividad endocrina del adipocito, con la producción de moléculas (adipoquinas) que influyen sobre los mecanismos inductores de insulinorresistencia (leptina, adiponectina, TNF-α, resistina, etc.) y disfunción de la célula beta. Se describen la disminución de la capacidad oxidativa en la cadena respiratoria mitocondrial y el renacer del concepto de lipogénesis de novo, ambas favoreciendo el acopie de lípido intracelular. En tejidos magros existen pequeñas reservas intracelulares de lípidos que mantienen la regulación de funciones esenciales, aunque si aparece una sobrecarga lipídica el fenómeno conduciría a una disfunción (lipotoxicidad) y a la muerte celular (lipoapoptosis). La tormentosa relación entre los lípidos y el islote de Langerhans va más allá del esfuerzo funcional que impone la insulinorresistencia periférica sobre la célula β, por efectos directos de los lípidos o de sus derivados sobre la función del islote pancreático. Sin déficit de insulina no se desarrolla diabetes.

Los intentos de institucionalización y “normalización universitaria” de la última dictadura. Ley universitaria, nuevo estatuto y concursos docentes en el caso de la Universidad de Buenos Aires (1980-1983).; The attempts of institutionalization and "university normalization" of the last dictatorship. University law, new statute and teaching contests in the case of the University of Buenos Aires (1980-1983) Seia, Guadalupe Andrea Una vez que la última dictadura argentina consideró derrotada a la llamada “subversión”, el Ministerio de Cultura y Educación nacional buscó la institucionalización del sistema universitario reformado a partir de la intervención de los claustros desde marzo de 1976. Para ello, en abril de 1980 se sancionó una nueva normativa universitaria (Ley N° 22207). En el presente artículo analizamos las particularidades del llamado proceso de “normalización” en la Universidad de Buenos Aires. Abordaremos nuestro caso de estudio con el objetivo de aportar a la complejización del conocimiento disponible sobre la historia del sistema universitario nacional, considerando que se trata de un todo heterogéneo. Asimismo, atenderemos a las posiciones de diferentes actores: autoridades, docentes y estudiantes.; The attempts of institutionalization and "university normalization" of the last dictatorship. university law, new statute and teaching contests in the case of the university of buenos aires (1980-1983). once the last argentine dictatorship considered defeated the so-called "subversion", the ministry of culture and national education sought the institutionalization of the university system reformed by the intervention since march 1976. for this, in april 1980 a new university regulation was enacted (law no. 22207). in this article we analyze the peculiarities of the so called "normalization" process in the university of buenos aires. we will approach our case study with the aim of contributing to the complexity of available knowledge about the history of the national university system, considering that it is a heterogeneous whole.

Pintando en La Gruta: Variabilidad y recurrencias en la producción de arte rupestre en una localidad del Extremo Sur del Macizo del Deseado (Santa Cruz, Patagonia, Argentina).; Painting in La Gruta: Variety and repetitions in the rock art production of a locality in the extreme South of Mazico del Deseado (Santa Cruz, Patagonia, Argentina) Fiore, Danae; Acevedo, Agustín; Franco, Nora Viviana En este trabajo se presentan los primeros resultados relativos al análisis del uso del color en la producción de pinturas rupestres de la localidad de La Gruta, región Extremo Sur del Macizo del Deseado (Patagonia Argentina). Para ello se analizan: a) los tonos empleados en la totalidad de motivos rupestres (N=168) registrados en siete sitios; b) siete muestras de pigmentos hallados en excavaciones de dos de estos sitios, cuyas dataciones abarcan desde el Holoceno temprano hasta el Holoceno tardío y c) los tipos de motivos emplazados en cada sitio. El análisis integrado de esta información provee resultados acerca de la variabilidad y recurrencias temporo-espaciales en la producción de arte rupestre por poblaciones de cazadores-recolectores de la localidad a lo largo de una secuencia arqueológica de diez mil años.; This paper presents the first results of the analysis of the use of colour in the production of rock paintings in La Gruta locality, extreme south of Macizo del Deseado region (Patagonia, Argentina). For this purpose, we analyse: a) the hues of all the rock art motifs (N=168) recorded in seven sites; b) seven pigment samples found in excavations of two of these sites, which are dated from early Holocene to recent Holocene times; c) the motif types located in each site. The integrated analysis of this information provides results regarding the variability and recurrent spatio-temporal patterns in rock art production by hunter-gatherer populations that occupied the locality during a ten-thousand year archaeological sequence.

Tamaño y viabilidad de semillas: implicancias en la evolución y conservación de Phaius tankervilleae (orchidaceae); Seed size and viability: implications on the evolution and conservation of Phaius tankervilleae (orchidaceae) Duarte, Evelyn Raquel; Mangeón, Vanesa; Küppers, Guillermo Federico; Rocha, Sandra Patricia; Niella, Fernando Omar Phaius tankervilleae es una orquídea terrestre altamente apreciada como ornamental y medicinal, razón por la cual se encuentra en peligro de extinción en algunos países como Australia y Japón. Generar información sobre las dimensiones y el vigor de la semilla es importante para entender aspectos de la evolución de la especie y encontrar métodos de conservación. Este estudio tuvo como fnalidad poner a prueba la hipótesis, de que el tamaño y viabilidad de las semillas de P. tankervilleae están positivamente relacionados con el tamaño del fruto. Para realizar el estudio se cosecharon frutos de diferentes tamaños, de los cuales se tomaron muestras de 2,5 mg de semillas por frutos. Se realizó la caracterización morfológica de las semillas mediante observaciones en microscopio. Las semillas de cada tamaño de fruto fueron sometidas a un test de Tetrazolio para determinar viabilidad y se les tomaron mediciones del largo, ancho y volumen tanto de la testa como del embrión. Las semillas con embrión son fusiformes y las vanas son fliformes, el embrión es relativamente pequeño y las semillas de fruto mediano son las que presentan menor espacio de aire. Los resultados confrman la hipótesis planteada, cuanto más pequeño es el fruto menor es el tamaño y la cantidad de semillas viables. Por consiguiente, si se desea tener mayor cantidad de semillas de buena calidad es recomendable cosechar frutos de mayor tamaño.; Phaius tankervilleae is a terrestrial orchid highly prized as ornamental and medicinal, which is why it is in danger of extinction in some countries such as Australia and Japan. Generating information on seed size and vigor is important in understanding aspects of the evolution of the species and finding conservation methods. This study aimed to test the hypothesis that the size and viability of P. tankervilleae seeds are positively related to fruit size. In order to carry out the study, fruits of different sizes were harvested, from which samples of 2.5 mg of seeds per fruit were taken. Morphological characterization of the seeds was carried out by means of microscope observations. A Tetrazolium test was carried out to determine the viability of seeds and measurements were taken of the length, width, and volume of both the testa and the embryo. Seeds with embryos are fusiform and the empty one are filiform, the embryo is relatively small and the seeds of medium size fruit are those that have less air space. The results confirm the hypothesis, the smaller the fruit the smaller the size and the number of viable seeds. Therefore, to have more seeds of good quality it is advisable to harvest larger fruits.

Description of the female of Lyssomanes miniaceus, with a new distribution record for L. belgranoi (Araneae: Salticidae); Descripción de la hembra de Lyssomanes miniaceus, con un nuevo registro de distribución para L. belgranoi (Araneae: Salticidae) Rubio, Gonzalo Daniel; Galvis, William; Nadal, María Florencia Gran número de especies nuevas de arañas están a la espera de ser descritas, y en muchos casos el conocimiento es incompleto porque se conoce un solo sexo. En esta contribución, la hembra de la araña saltadora Lyssomanes miniaseus es descrita y por primera vez se ilustra su morfología. La hembra se distingue por tener las espermatecas esféricas, ligeramente ovales, una posición atrasada de los orificios copulatorios, y pelos blancos esparcidos ventralmente sobre los fémures I y II; podría ser este último carácter una característica compartida por ambos sexos potencialmente única a esta especie. Adicionalmente, se presenta aquí un nuevo registro más al sur y una nueva ilustración de la especie poco conocida L. belgranoi.; Numerous new spider species are waiting to be described, and in many cases knowledge is incomplete because species are known from a single sex. In this contribution the female of the jumping spider Lyssomanes miniaceus is described and its morphology is illustrated. Females are distinguished by having spherical, slightly oval spermathecae, the copulatory openings towards the back, and sparse white hairs ventrally on femora I and II; the last character could be a unique trait shared by both sexes. Additionally, a new southernmost record plus new illustration of the little-known species L. belgranoi are given.

Satisfacción y motivación de la cirugía estética en mujeres y su relación con los esquemas desadaptativos tempranos; Satisfaction and motivation of cosmetic surgery in women and the relation with early maladaptive schemas Moretti, María Paula; Casari, Leandro Martín El objetivo de esta investigación fue investigar los Esquemas Desadaptativos Tempranos (EDT) enmujeres con cirugías estéticas, e indagar si existían relaciones con: satisfacción, motivación hacianuevas cirugías y variables relacionadas a la intervención quirúrgica. Se trabajó con una muestrade 67 mujeres de entre 18 y 40 años con al menos una cirugía, administrando el CuestionarioEsquemas Desadaptativos Tempranos de Young y una encuesta Ad Hoc. Como resultado el esquemaEstándares Inflexibles se encontró en más del 50 % y se encontraron correlaciones significativascon las variables analizadas: motivación, satisfacción y variables quirúrgicas con EDT(cantidad, edad y antigüedad). Se discuten los resultados en función de la influencia entre losEDT y las intervenciones quirúrgicas estéticas.; The purpose of this study was to investigate the Early Maladaptative Schemas (EMS) in women who have undergone cosmetic surgeries (CS) and to research if there was a relation to the satis faction with the CS, the motivation to undergo more surgeries and the variables related to cos metic surgery. A non-experimental, cross-sectional, descriptive correctional study was carried out. The deliberately selected sample was comprised of 67 women between 18 and 40 years old who had undergone, at least, one cosmetic surgery. Data was collected from the responses to Jeffrey Young's questionnaire entitled Early Maladaptive Schemas and an ad hoc survey. As a result, from the investigation, it was observed that the schema of Unrelenting Standards was found in more than 50 % of the sample, and meaningful correlations with the analyzed variables were found: motivation, satisfaction and surgical variables with EMS (quantity, age and age of the first one). The results are discussed in relation to the influence among the EMS and the cosmetic surgeries.

Producción y bienestar social en el campo mendocino: el Estado y las posibilidades de capacitación agrícola durante el primer peronismo (Argentina); Production and Social Welfare in the country in Mendoza: The state and the possibilities for agricultural education during the first period of peronism (Argentina); Produção e bem-estar social no campo mendoncino: o Estado e as possibilidades de capacitação agrícola durante o primeiro peronismo (Argentina); Production et bien-être social dans la campagne mendocina: l'État et les possibilités de formation agricole pendant le premier péronisme (Argentina) Hirschegger, Ivana Se busca identificar políticas públicas en materia de enseñanza técnica-agrícola para los sectores rurales de la provincia de Mendoza, con el objetivo de encontrar, dentro de un contexto socio-productivo específico, soluciones no sólo a la escasez de mano de obra agrícola sino también a los altos niveles de analfabetismo y deserción estudiantil de las zonas rurales y que en definitiva repercuten en las condiciones de vida de la población. El trabajo atiende aspectos como las demandas de los diferentes sectores representantes del agro, el papel de las escuelas rurales y las técnicas de oficio, y otras instancias institucionales de difusión de conocimientos como los clubes agrícolas, las misiones monotécnicas, las estaciones experimentales y la participación de la Universidad Nacional de Cuyo. A partir de este estudio se explican entonces los avances en materia de enseñanza, el alcance de las iniciativas estatales, las falencias de planificación, como también la relación de coordinación entre diferentes jurisdicciones. Entre las fuentes consultadas se pueden mencionar los periódicos provinciales y departamentales, estadísticas (provinciales y nacionales), revistas de divulgación, y toda aquella documentación oficial de tipo económica y social.; This articles aims at identifying public agricultural technique education policy for the rural areas of the province of Mendoza. In this province, the manpower shortage for rural tasks, in a context in which agricultural production had diminished the dissemination of agricultural technique education knowledge by the State was necessary. Although some progress was made in education and State initiatives reached the rural sectors, shortcomings in the planning, the distances, labour issues and socio-economic problems, as well as the lack of budgetary resources limited the possibilities of access to this type of orientation. In this regard, practical education on agricultural tasks failed to be released massively by the State or applied by the majority of farmers. The sources consulted include the provincial and departmental newspapers, statistics (provincial and national), journals, and all social and economic official documentation.; Buscamos identificar políticas públicas em matéria de ensino técnico-agrícola para os setores rurais da província de Mendoza. Nesta província, a escassez de mão-de-obra especializada para tarefas rurais, em um contexto no qual a produção agrícola havia diminuído, fez com que se tornasse necessária a difusão de conhecimentos técnico-agrícolas por parte do Estado. Embora ocorressem certos avanços em relação ao ensino e parte das iniciativas estatais alcançavam determinados setores rurais, falências na pla-nificação, as distâncias, questões laborais e problemas socioeconómicos, assim como também a falta de recursos orçamentais limitaram as possibilidades de acesso a este tipo de orientação. Neste sentido, a educação prática sobre tarefas agrícolas não conseguiu ser difundida de maneira massiva pelo Estado, muito menos aplicada pela maioria dos agricultores. Entre as fontes consultadas podemos mencionar os jornais provinciais e departamentais, estatísticas (provinciais e nacionais), revistas de divulgação e toda aquela documentação oficial de tipo económica e social.; Le but est d'identifier les politiques publiques en matière d'enseignement technique-agricole pour les secteurs ruraux de la province de Mendoza. Dans cette zone, le manque de main d'œuvre spécialisée pour les activités rurales, dans un contexte où la production agricole avait diminué, demandait péremptoirement la diffusion de connaissances tech-nico-agricoles de la part de l'État. Malgré quelques progrès en matière d'enseignement et bien qu'une partie des initiatives de l'État aient atteint quelques secteurs ruraux, des faiblesses dans la planification, les distances, des affaires du travail et des problèmes so-cioéconomiques, ainsi que le manque de budget ont limité les possibilités d'accès à cette sorte de formation. Dans ce sens-là, l'éducation pratique sur des activités agricoles n'a pas pu être diffusée de manière massive par l'État ni appliquée par la plupart des agriculteurs. Parmi les sources consultées, faut-il mentionner les journaux provinciaux et départementaux, des statistiques (provinciales et nationales), des revues de divulgation et des documents officiels de nature économique et sociale.

Effects of an eccentric inner Jupiter on the dynamical evolution of icy body reservoirs in a planetary scattering scenario Zanardi, Macarena; de Elia, Gonzalo Carlos; Di Sisto, Romina Paula; Naoz, S.; Li, G.; Guilera, O. M.; Brunini, A. Aims. We analyze the dynamics of small body reservoirs under the effects of an eccentric inner giant planet resulting from a planetary scattering event around a 0.5 M⊙ star. Methods. First, we used a semi-analytical model to define the properties of the protoplanetary disk that lead to the formation of three Jupiter-mass planets. Then, we carried out N-body simulations assuming that the planets are close to their stability limit together with an outer planetesimal disk. In particular, the present work focused on the analysis of N-body simulations in which a single Jupiter-mass planet survives after the dynamical instability event. Results. Our simulations produce outer small body reservoirs with particles on prograde and retrograde orbits, and other ones whose orbital plane flips from prograde to retrograde and back again along their evolution (“Type-F particles”). We find strong correlations between the inclination i and the ascending node longitude Ω of Type-F particles. First, Ω librates around 90° or/and 270°. This property represents a necessary and sufficient condition for the flipping of an orbit. Moreover, the libration periods of i and Ω are equal and they are out to phase by a quarter period. We also remark that the larger the libration amplitude of i, the larger the libration amplitude of Ω. We analyze the orbital parameters of Type-F particles immediately after the instability event (post IE orbital parameters), when a single Jupiter-mass planet survives in the system. Our results suggest that the orbit of a particle can flip for any value of its post IE eccentricity, although we find only two Type-F particles with post IE inclinations i ≲ 17°. Finally, our study indicates that the minimum value of the inclination of the Type-F particles in a given system decreases with an increase in the eccentricity of the giant planet.

Una reflexión sobre el realismo literario: Cuentos claros de Antonio Di Benedetto Arce, Rafael Gerardo Este trabajo propone una lectura de Cuentos claros (1957) de Antonio Di Benedetto. El punto de partida para estas reflexiones concierne al programa narrativo experimental y vanguardista del escritor. Cuentos claros, en contraste, se presenta como un conjunto de relatos realistas, incluso con cierto sesgo regionalista. A partir de su título original (Grot), el trabajo plantea como hipótesis que estos cuentos reflexionan sobre el realismo literario, sus alcances y sus límites, en clave de grotesco literario.; This paper proposes a reading of Cuentos claros (1957) by Antonio Di Benedetto. The starting point for his reflections centers on the experimental and avant-garde writer's narrative program. By contrast, Cuentos claros is presented as a collection of realistic stories that even have a certain regionalist bias. From its original title (Grot), this study hypothesizes that these stories reflect on literary realism, and that their scope and limits can be seen in terms of literary grotesque.

Volvariella (Pluteacae, Basidiomycota) en el Norte de la Argentina; Volvariella (Pluteaceae, Basidiomycota) from Northen Argentina Niveiro, Nicolás; Ramírez, Natalia Andrea; Popoff, Orlando Fabian; Alberto, Edgardo Omar Three species of Volvariella from Northern Argentina are illustrated and described. Volvariella taylorii, known from the Yungas and the Paranaense Rain Forests; V. subxerophytica, known exclusively from the xerophytic forest from "chaqueña" region, and V. pusilla which was found in Chaco and Tucumán provinces. The two former species are characterized by having brownish-grayish volva and the fibrillose pileus, and the later by its whitish-grayish volva and the finely and delicately fibrillose surface of the pileus. Volvariella taylorii is recorded for the first time from Argentina and the area of distribution of V. subxerophytica is expanded towards the oriental area of the "chaqueña" region. It is important to mention that V. subxerophytica was only known by the type material and that in this work the original description is improved with data obtained from new specimens.

Pensar con sonidos: Los universos musicales en El Trino del Diablo de Daniel Moyano; Thinking with Sounds: Musical Universes in El Trino del Diablo by Daniel Moyano López, Irene Noemí La música ocupa un lugar predominante en la producción literaria de Daniel Moyano. Su escritura entrama en diversos planos –semántico, formal, ideológico- referencias y procedimientos provenientes del discurso musical construyendo un espacio textual complejo. Consideramos por ello que a través de su estudio es posible colaborar en la reflexión acerca de las múltiples formas de producción de sentido que se generan en el diálogo entre lenguajes artísticos, en este caso entre música y literatura. En este trabajo realizamos una lectura de El trino del diablo para mostrar las formas en que el universo narrativo de la novela se configura a través de la incorporación de mitos y concepciones acerca de la música y los intérpretes, incidiendo en la construcción de espacios de pertenencia y marcos de referencia cultural e identitaria. Asimismo, la lectura en torno a la textualización de prácticas, valores y referencias musicales constituye una forma posible de conocimiento y comprensión del mundo político y social de los años 1970 en Argentina.; Music plays a major role in Daniel Moyano's literary production. References and procedures coming from musical discourse are interwoven in his writing creating a complex textual space in various planes –semantic, formal, and ideological. Therefore, we consider that studying his writing allows us to contribute to the considerations about the multiple ways of sense production created in the dialog between artistic languages, in this case, between music and literature. In this paper, we do a reading of El trino del diablo* in order to show the ways in which the narrative universe of the novel takes shape by means of the incorporation of myths and conceptions about music and interpreters, influencing the construction of areas of membership and cultural and identity frames of reference. Likewise, reading taking into consideration the textualization of practices, values, and musical references is a possible way of knowing and understanding the political and social world of the 1970s in Argentina.

Sex morphs and invasiveness of a fleshy-fruited tree in natural grasslands from Argentina Amodeo, Martín Raúl; Zalba, Sergio Martín Invasiveness has usually been studied as a species-level attribute; nevertheless, phenotypic differences between individuals in a population can lead to significant variations in colonization ability. In this paper, we analyse the potential effects of sex morphs of Prunus mahaleb, a gynodioecius fleshy-fruited tree, on its invasiveness in natural grasslands in the southern Argentine Pampas. We assessed the abundance of both hermaphrodite and female plants and compared their fecundity, propagule size and germination response. We found that the females were less abundant in the invasive populations studied, apparently since the beginning of the colonization. However, our results demonstrated that at the present time females do not show any fecundity reduction, which clearly shows that P. mahaleb has established an effective interaction with generalist pollinators which compensates for the apparent disadvantage of females. Fruit set showed a wider range of variability over time in the females than in the hermaphrodites, which could be the consequence of greater susceptibility to changes in the activity of pollinators. We found no evidence of a female benefit due to reallocation of resources or better outcrossed progeny considering propagule size and germination. We discuss the relative importance of sex morphs and interactions at different stages of the invasion process.

When sperm meets egg: the spark of new life Wozniak, Katherine Lynn; Luque, Guillermina Maria; Ahn, Soo Hyun Activation following fertilization reawakens the quiescent egg and inhibits polyspermy. Oscillating cytoplasmic Ca2+ concentrations ([Ca2+ ]) during egg activation are a highly conserved event that have persisted through the course of evolution. For example, fertilization in the starfish Asterina miniata results in two Ca2+ -dependent processes in the fertilized egg.

Improving the water resistance of epoxy–anhydride matrices by the incorporation of bentonite Capiel, Guillermina; Uicich, Julieta; Alvarez, Vera Alejandra; Montemartini, Pablo Ezequiel Epoxy-anhydride based polymers are commonly used as a matrix in pipeline systemsexposed to water during their in-service life. Water absorption at moderatetemperatures and/or at long exposure times could lead to irreversible hydrolysisreaction decreasing considerably the polymer overall performance. A strategy toenhance the barrier properties of epoxy resins is to add nano-fillers to traditional matrices. In this work, we added bentonite and chemically modified bentonite to this purpose. Water absorption of the resulting materials at three different temperatures (22°C, 80 °C and 93 °C) was studied and simultaneously, the evolution during the immersion tests of glass transition temperature and flexural modulus was recorded.Long-term gravimetric results showed that composites with chemically modified bentonite produce a delay on the hydrolysis of epoxy-anhydride matrix, which is a relevant result, due to the tough application and uses of the system, from the technological point of view.