Forbidden subgraphs and the König–Egerváry property Bonomo, Flavia; Dourado, Mitre C.; Duran, Guillermo Alfredo; Faria, Luerbio; Grippo, Luciano Norberto; Safe, Martin Dario The matching number of a graph is the maximum size of a set of vertex-disjoint edges. The transversal number is the minimum number of vertices needed to meet every edge. A graph has the König-Egerváry property if its matching number equals its transversal number. Lovász proved a characterization of graphs having the König-Egerváry property by means of forbidden subgraphs within graphs with a perfect matching. Korach, Nguyen, and Peis proposed an extension of Lovász´s result to a characterization of all graphs having the König-Egerváry property in terms of forbidden configurations (which are certain arrangements of a subgraph and a maximum matching). In this work, we prove a characterization of graphs having the König-Egerváry property by means of forbidden subgraphs which is a strengthened version of the characterization by Korach et al. Using our characterization of graphs with the König-Egerváry property, we also prove a forbidden subgraph characterization for the class of edge-perfect graphs.

When and why noise correlations are important in neural decoding Eyherabide, Hugo Gabriel; Samengo, Ines Information may be encoded both in the individual activity of neurons and in the correlations between their activities. Understanding whether knowledge of noise correlations is required to decode all the encoded information is fundamental for constructing computational models, brain–machine interfaces, and neuroprosthetics. If correlations can be ignored with tolerable losses of information, the readout of neural signals is simplified dramatically. To that end, previous studies have constructed decoders assuming that neurons fire independently and then derived bounds for the information that is lost. However, here we show that previous bounds were not tight and overestimated the importance of noise correlations. In this study, we quantify the exact loss of information induced by ignoring noise correlations and show why previous estimations were not tight. Further, by studying the elementary parts of the decoding process, we determine when and why information is lost on a single-response basis. We introduce the minimum decoding error to assess the distinctive role of noise correlations under natural conditions. We conclude that all of the encoded information can be decoded without knowledge of noise correlations in many more situations than previously thought.

Subjetividad y política: tres lecturas discursivas del sujeto político Dagatti, Mariano Jesús Esta presentación tiene por objetivo realizar un comentario de investigaciones discursivas en torno a la cuestión de la subjetividad política, con el fin de colaborar en el diseño de un marco teórico para estudiar la conformación de identidades en el discurso político. El texto propone, así, un recorrido por los aportes de la teoría de los discursos sociales de E. Verón, de la teoría de la hegemonía de E. Laclau y de los trabajos de D. Maingueneau sobre la noción de ethos. Perspectivas disímiles surgidas en el contexto del giro discursivo, estos estudios parten de una crítica del sujeto como fuente del sentido y de la determinación como característica de la comunicación. El estado de la cuestión permite subrayar la importancia de estos desarrollos para investigar los procesos de credibilidad e identificación que atraviesan el juego político: ruptura de la linealidad, disimilitud de las lógicas de funcionamiento, circulación semiótica y articulación hegemónica, imágenes de sí e imágenes del cuerpo social, instituciones, estilos y colectivos son algunas de las categorías involucradas en esta ponencia. Como conclusión, mencionamos el peso decisivo de los liderazgos en la interfaz entre las lógicas institucionales e individuales. Esta afirmación se contrapone a la condena que éstos reciben por parte de quienes entreven en la presencia de un líder fuerte un atentado a la verdadera democracia.; La presentazione è destinata a fare un commento di ricerca discorsiva intorno alla questione della soggettività politica. L'obiettivo è quello di contribuire a progettare un quadro teorico per studiare la formazione di identità nel discorso politico. Si propone, pertanto, una lettura dei contributi della teoria del discorso sociale di E. Veron, della teoria dell’egemonia di E. Laclau e della ricerca di D. Maingueneau sul concetto di ethos. Prospettive dissimili che sorgono nel contesto della “svolta discorsiva”, questi studi si basano su una revisione dell soggeto come fonte di significato e della determinazione comme caratteristica centrale della comunicazione. Lo stato di cose serve a sottolineare l'importanza di questi sviluppi per studiare i processi di credibilità e di identificazione che abbracciano il gioco politico: rottura della linearità, dissimilarità delle logiche di funzionamento, circolazione semiotica e articolazione egemonica, ethos e immagini di corpo sociale, le istituzioni, gli stili e collettivi sono alcune delle categorie coinvolte in questo lavoro. In conclusione, citiamo il peso determinante della leadership nella interfaccia tra logiche individuali e istituzionali. Questa affermazione è in contrasto con la convinzione che essi ricevono da quelli intravisto in presenza di un forte leader di un tentativo di vera democrazia.; This paper aims to conduct a review of discourse research around the issue of political subjectivity. The goal is to help design a theoretical framework for studying the formation of identity in political discourse. It proposes, therefore, a journey through the contributions of social discourse theory of E. Verón, hegemony theory of E. Laclau and the work of D. Maingueneau on the notion of ethos. Dissimilar perspectives arising in the context of the discursive turn, these studies are based on a review of the subject as a source of meaning and of the determination as a central feature of communication. The state of the art serves to underline the importance of these developments to investigate the credibility and identification processes spanning the political game: breakdown of linearity, dissimilarity of the operation logic, semiotics circulation and hegemonic articulation, self-images and social imaginary, institutions, styles and collective are some of the categories involved in this paper. In conclusion, we mention the decisive weight of leadership at the interface between individual and institutional logics. This statement is contrary to the idea from those who glimpsed in the presence of a strong leader an attempt to true democracy.

Invariancia de Medidas de la prueba de figuras del Test de Pensamiento Creativo de Torrance según la edad: Un estudio en niños y adolescentes de habla hispana; Measurement Invariance of Torrance Test of Creative Thinking Figural Scores across Age: A study in Spanish-Speaking Children and Adolescents.; Invariância de Medidas da prova de figuras do Teste de Pensamento Criativo de Torrance segundo a idade: Um estudo em crianças e adolescentes de língua espanhola. Krumm, Gabriela Liliana; Arán Filippetti, Vanessa; Lemos, Viviana Noemí; Aranguren, María; Vargas Rubilar, Jael Alejandra En base a un estudio previo que indica que el constructo creatividad operacionalizado con el Test de Pensamiento Creativo de Torrance (TTCT) de Figuras está compuesto por dos factores Innovación y Adaptación, en niños de habla hispana (Krumm, Lemos & Arán Filippetti, en prensa), el objetivo de este trabajo fue comprobar si esta estructura es invariante según la edad de los sujetos. Se trabajó con una muestra de 652 niños y adolescentes de 9 a 17 años de ambos sexos de habla hispana divididos en tres grupos: (a) 9-10 años, (b) 11-13 años y (c) 16-17 años. El Análisis Factorial Confirmatorio (AFC) mostró que la estructura del TTCT está integrada por dos factores correlacionados, Innovación y Adaptación en las tres muestras de estudio. Además, los resultados del AFC multigrupo revelaron que la estructura de dos factores es invariante (configural y métrica) a través del edad, lo que significa que los niños y adolescentes conceptualizan el constructo Creatividad de la misma manera. Finalmente, el análisis multivariado de varianza (MANOVA) reveló un efecto significativo de la edad en todas las subescalas. Estos datos muestran la importancia de la edad como un factor a tener en cuenta en el estudio del potencial creativo a través del TTCT-Figuras.; On the basis of a previous study carried out with Spanish-speaking children which indicates that the Creativity construct, operationalized by means of the Torrance Tests of Creative Thinking (TTCT)-Figural, consists of two factors –Innovation and Adaptation– (Krumm, Lemos & Arán Filippetti, in press), the objective of the present work was to prove whether this structure is invariant across age. A sample of 652 Spanish-speaking children and adolescents aged 9-17 years of both sexes was tested. It was in turn divided into three age groups: (a) 9-10, (b) 11-13 and (c) 16 -17 years. Confirmatory Factor Analysis (CFA) showed that in each group of the sample, the structure of the TTCT is composed of two correlated factors, namely Innovation and Adaptation. In addition, Multigroup CFA demonstrated that the two-factor solution was actually invariant (configural and metric) across age, meaning that children and adolescents equally conceptualize the Creativity construct. Finally, MANOVA showed a significant age effect on every subscale. These data suggest the relevance of considering the age factor when assessing the creative potential through the TTCT-Figural.

Sistema de control para el almacenamiento intermedio de gasolina natural Oteiza, Paola Patricia; Rodriguez, Diego Alejandro; Brignole, Nelida Beatriz En Rodríguez et al., Ind Eng Chem Res., 52 (25), 8579−8588 (2013) se desarrolló un paquete general con el fin de encontrar una óptima red de cañerías para el transporte de gasolina natural proveniente de yacimientos gasíferos. Con esta herramienta, se analizó la distribución de líneas de transporte para yacimientos que se encuentran en la provincia de Santa Cruz (Argentina) y se localizaron los nodos concentradores. En estos nodos se proyecta almacenar la gasolina natural. Entonces, se desea controlar en forma óptima estos tanques con el objetivo de garantizar el suministro a la planta de procesamiento. Por lo tanto, en este trabajo analizamos la respuesta dinámica del sistema y, como primera etapa del estudio, optimizamos conjuntamente mediante Algoritmos Genéticos los parámetros de un controlador Proporcional-Integral-Derivativo y otro Proporcional-Integral de forma desacoplada.

Ordovician chitinozoans and marine phytoplankton of the Central Andean Basin, northwestern Argentina: A biostratigraphic and paleobiogeographic approach de la Puente, Graciela Susana; Rubinstein, Claudia Viviana Ordovician deposits from the Central Andean Basin cover a vast region with thick exposed sequences in several areas, including the Sierras Subandinas, Cordillera Oriental and Puna geological provinces of northwestern Argentina. This basin was situated along the active margin of a Paleozoic foreland basin in western Gondwana. Continuous sedimentation occurred in different paleoenvironments from east to west: marginal marine settings with estuarine and deltaic deposits (Sierras Subandinas), shallow marine shelf environments with large clastic deposits in the central part (Cordillera Oriental–eastern Puna), and deep marine deposits with volcaniclastic supplies (western Puna). Limited biostratigraphic and chronostratigraphic data from these sequences are known from graptolites, conodonts and trilobites, and more recently also from palynomorphs. An analysis of Ordovician sections from the different sedimentological settings of northwestern Argentina produced 60 chitinozoan-bearing samples from which 19 genera and 45 species have been recorded. Four chitinozoan assemblages were observed in the Lower Ordovician from northwestern Argentina. Correlations with other fossil groups provide independent biostratigraphic control. A stratigraphic range chart of selected acritarch taxa throughout the Ordovician of the Central Andean Basin is developed and biostratigrapic or potential biostratigraphic markers for the basin are proposed. In northwestern Argentina, Late Ordovician chitinozoan assemblages display affinities with Polar to Subpolar faunas.

Design and performance of a compact subthermal neutron source for an Electron Linear Accelerator Tartaglione, Aureliano; Galván Josa, Víctor Martín; Dawidowski, Javier; Cantargi, Florencia; Blostein, Juan Jeronimo We present the design, construction and performance of a compact subthermal neutron source to be operated at the Bariloche Electron LINAC. The design was based on the premise of keeping the moderator temperature stable at 77 K for at least seven hours without refilling liquid nitrogen. Two moderator materials in semi-cylindrical geometry were studied: polyethylene and mesitylene. The effective moderator volumes were optimized by Monte Carlo simulations. Experimental data and calculations corresponding to the neutron production as a function of the neutron energy for those materials at room temperature and at 77 K were compared. We observed that the rate of subthermal neutrons, compared to epithermal neutrons, increases up to five times for both moderators when they are cooled down.

Applying Cost-distance analysis for forest disease risk mapping: Phytophthora austrocedrae as an example la Manna, Ludmila Andrea; Greslebin, Alina Gabriela; Matteucci, Silvia Diana Cost-distance model analyzes the relative difficulty in reaching each spot of the landscape for the object or species under study. It calculates the effective distance, which is the Euclidian distance modified by the friction to movement through different landscape elements. This work deals with the application of cost-distance analysis in forest pathology, considering Austrocedrus chilensis root rot caused by Phytophthora austrocedrae as an example. In this case, cost-distance analysis was used to determine the relative difficulty for the pathogen to reach healthy forest patches from the patches that are presently diseased. Friction values were assigned on the basis of abiotic conditions, biological characteristics of the pathogen and host presence. Since cattle may be a vehicle for Phytophthora dispersion, three hypothetical situations of ranching were considered. Cost-distance application resulted useful to define minimum risk areas for conservation purposes. In the study case, minimum risk area strongly varied in response to cattle presence. This study provided valuable information for A. chilensis disease management and showed one of the broad applications of cost-distance analysis in forestry.

Susana Zanetti en el recuerdo. Semblanzas Sancholuz, Carolina Coordinación de un Dossier de homenaje a la trayectoria de Susana Zanetti en el campo de los estudios literarios latinoamericanos, donde su figura fue pionera a la hora de diseñar una red de investigaciones y formación de recursos humanos en la especialidad.

Complex Energy Landscape of a Giant Repeat Protein Tsytlonok, Maksym; Craig, Patricio Oliver; Sivertsson, Elin; Serquera, David; Perrett, Sarah; Best, Robert B.; Wolynes, Peter G.; Itzhaki, Laura S. Here, we reveal a remarkable complexity in the unfolding of giant HEAT-repeat protein PR65/A, a molecular adaptor for the heterotrimeric PP2A phosphatases. The repeat array ruptures at multiple sites, leading to intermediate states with noncontiguous folded subdomains. There is a dominant sequence of unfolding, which reflects a nonuniform stability distribution across the repeat array and can be rationalized by theoretical models accounting for heterogeneous contact density in the folded structure. Unfolding of certain intermediates is, however, competitive, leading to parallel unfolding pathways. The low-stability, central repeats sample unfolded conformations under physiological conditions, suggesting how folding directs function: certain regions present rigid motifs for molecular recognition, whereas others have the flexibility with which to broaden the search area, as in the fly-casting mechanism. Partial unfolding of PR65/A also impacts catalysis by altering the proximity of bound catalytic subunit and substrate. Thus, the repeat array orchestrates the assembly and activity of PP2A.

Consensus in the search for areas of endemism Aagesen, Lone; Szumik, Claudia Adriana; Goloboff, Pablo Augusto For ambiguous data sets, methods to determine areas of endemism based on an optimality criterion may result in large numbers of candidate areas, and thus some kind of consensus technique is required to summarize those results. This paper presents a formal description of two possible algorithms or rules for area consensus, which merge candidate areas if they share a user-defined percentage of the species that define each candidate area. The two consensus rules summarize ambiguity in different ways. Applying the ?tight? rule will result in consensus areas defined by species present in nearly all cells, but in cases where there is significant conflict the result may be a high number of distinct consensus areas. The ?loose? consensus rule is more agglomerative and will result in fewer consensus areas, combining areas when overlapping distribution patterns exist. Depending on the aim and scale of the analysis, the two consensus rules can be used either to delimit areas of endemism with sharp boundaries or to identify diffuse and gradually replacing biogeographical patterns. These two different approaches are discussed and demonstrated using real data.

Hierarchical habitat selection and reproductive success of the Ringed Warbling-finch in Chaco woodlands; Selección Jerárquica de Hábitat y Éxito Reproductivo de Poospiza torquata en el Bosque Chaqueño Sánchez, Rocío; Blendinger, Pedro Gerardo; Moyano Wagner, Eugenia; Martín, Eduardo Las aves reproductoras deben seleccionar el hábitat a múltiples escalas, desde los paisajes hasta los sitios de nidificación. Es importante entender cómo las aves toman estas decisiones y las relaciones entre estas selecciones y el éxito reproductivo. Durante 3 años, estudiamos la selección del sitio de nidificación de Poospiza torquata en el Chaco semiárido de Argentina a las escalas de paisaje, parche de nidificación y sitio de nidificación. A la escala de paisaje, P. torquata estableció los territorios de nidificación exclusivamente en arbustales-pastizales. Dentro de los arbustales-pastizales, los parches de nidificación y los sitios de nidificación seleccionados difirieron en pocos atributos de la vegetación de los parches y sitios que estaban disponibles, y estas diferencias variaron de año en año. Solo en el año en que la supervivencia de la nidada y el éxito reproductivo fueron los más bajos, las características entre los sitios con nidos exitosos y con nidos depredados variaron claramente. P. torquata selecciona las características del hábitat a las escalas de paisaje, parche de nidificación y sitio de nidificación. Las implicancias de las selecciones a las escalas de parche de nidificación y sitio de nidificación parecen variar por año, pero la presencia de arbustos, particularmente de Geoffroea decorticans y Ziziphus mistol, fueron características claves en la selección. La especie parece ser plástica en su selección del parche de nidificación y en su sitio de nidificación, tal vez debido a que estas selecciones no conducen a ventajas selecticas consistentes.; Las aves reproductoras deben seleccionar el hábitat a múltiples escalas, desde los paisajes hasta los sitios de nidificación. Es importante entender cómo las aves toman estas decisiones y las relaciones entre estas selecciones y el éxito reproductivo. Durante 3 años, estudiamos la selección del sitio de nidificación de Poospiza torquata en el Chaco semiárido de Argentina a las escalas de paisaje, parche de nidificación y sitio de nidificación. A la escala de paisaje, P. torquata estableció los territorios de nidificación exclusivamente en arbustales-pastizales. Dentro de los arbustales-pastizales, los parches de nidificación y los sitios de nidificación seleccionados difirieron en pocos atributos de la vegetación de los parches y sitios que estaban disponibles, y estas diferencias variaron de año en año. Solo en el año en que la supervivencia de la nidada y el éxito reproductivo fueron los más bajos, las características entre los sitios con nidos exitosos y con nidos depredados variaron claramente. P. torquata selecciona las características del hábitat a las escalas de paisaje, parche de nidificación y sitio de nidificación. Las implicancias de las selecciones a las escalas de parche de nidificación y sitio de nidificación parecen variar por año, pero la presencia de arbustos, particularmente de Geoffroea decorticans y Ziziphus mistol, fueron características claves en la selección. La especie parece ser plástica en su selección del parche de nidificación y en su sitio de nidificación, tal vez debido a que estas selecciones no conducen a ventajas selecticas consistentes.

Rescate arqueológico de restos óseos humanos en el sitio Laguna Seca (pdo. de Gral. Lamadrid, pcia. de Buenos Aires) Gonzalez, Mariela Edith; Kaufmann, Cristian Ariel RESUMEN. arqueológico de un entierro humano descubierto por pobladores locales en un predio ubicado a 15 kilómetros al norte de la ciudad de General Lamadrid, provincia de Buenos Aires. Los restos óseos se encontraban en el borde desmoronado de una pequeña barranca ubicada al costado de un camino que cortaba una lomada. Los objetivos planteados fueron: conocer la integridad del esqueleto, inferir la modalidad de entierro, estimar la cronología del evento inhumatorio y evaluar cuáles fueron los principales procesos postdepositacionales que afectaron a los elementos óseos. La compleja imbricación de los elementos óseos y el estado de fragmentación que presentaban, llevó a extraer el enterratorio en forma de bloque. Las tareas de excavación en el laboratorio permitieron recuperar un total de 121 especímenes óseos correspondientes a un único individuo adulto de sexo femenino datado en 579 ± 42 años AP. El registro de algunos elementos óseos articulados sugiere que se trata de un enterratorio primario que sufrió importantes modificaciones luego del evento de inhumación. Las alteraciones postdepositacionales, como el desplazamiento de las piezas óseas, la fragmentación de los huesos y la pérdida de varias unidades anatómicas, han estado vinculadas, en gran parte, a procesos naturales y antrópicos modernos.

Two-Dimensional Speckle Tracking Echocardiography for Early Detection of Myocardial Damage in Young Patients with Fabry Disease Saccheri, María C.; Cianciulli, Tomás F.; Lax, Jorge A.; Gagliargi, Juan A.; Caceres, Guillermo L.; Quarin, Alejandra E.; Kisinovsky, Issac; Rozenfeld, Paula Adriana; Reisin, Ricardo C. Fabry disease (FD) is characterized by left ventricular hypertrophy (LVH). Conventional echocardiography is not sensitive enough to perform the preclinical diagnosis To assess whether longitudinal myocardial strain of the left ventricle (LV), using speckle tracking, is useful to detect early myocardial involvement in FD. Forty‐four patients with FD who were diagnosed with genetic testing were prospectively included and were compared to a sex‐matched control group. They were divided into three groups: 22 with LVH (Group I), 22 without LVH (Group II), and 22 healthy volunteers (Group III). LV longitudinal strain was measured from the apical views. An ANOVA test was used for multiple comparisons for variables with a normal distribution, and a Kruskal–Wallis test was used for variables with non‐Gaussian distribution. Longitudinal LV strain was different in the three groups: it was ≥−15% in at least one segment in all Group I patients, in 50% of patients of Group II and in no patient of Group III. Seventy percent of the segments with abnormal strain in Group II were located in the basal regions (32/46). These findings show that the presence of at least one strain value ≥−15% demonstrates subclinical myocardial dysfunction in patients with preclinical FD. Longitudinal myocardial LV strain measured with speckle tracking is a useful tool to detect early myocardial involvement in young patients with FD. This information allows the detection and treatment of myocardial dysfunction at an early stage, which is of high clinical importance.

Technology-based Startup Valuation Using Real Options with Edgeworth Expansion Milanesi, Gastón; Pesce, Gabriela; El Alabi, Emilio There exists extreme difficulties while trying to valuate, using traditional valuation methods, startup firms which are dedicated to technological development. Among those methods, we could mention the balance sheet-based ones, the relative valuation ones, the cash flow discounting-based ones, and the goodwill-based ones. Those difficulties are the absence of comparable companies, the inexistence of historical data, the complexity to estimate volatility, and the number of intangible assets which give worth to the firm. This paper proposes to valuate this type of entrepreneurships using real options theory making adjustments that allow us to abandon the assumption of normal returns. Methodologically, we use real options theory adapted through Edgeworth expansion. It allows abandoning the probability of normal distribution assumption incorporating higher moments such us asymmetry and kurtosis. Obtained results let us show how the firm?s value and its strategic options are affected by stochastic higher moments? behavior. These are often not considered because of assuming a normal behavior related to a random path of the underlying assets.

Properties of triticale protein films and their relation to plasticizing-antiplasticizing effects of glycerol and sorbitol Aguirre, Alicia del Valle; Borneo Benista, Rafael; Leon, Alberto Edel Triticale protein films were prepared and the influence of glycerol and sorbitol on their functional properties was investigated. At equal plasticizer concentration glycerol-plasticized triticale films had higher moisture content at a given relative humidity than did sorbitol films. Films plasticized with sorbitol exhibited higher solubility than glycerol-plasticized films. Mechanical properties of films are strongly affected by relative humidity and considerably varied with the type and concentration of plasticizer used. Glycerol exhibited better plasticizing effect for triticale films. Tensile strength, Young's modulus and puncture force of the films decreased as the glycerol content increased. The increase in the tensile strength and Young's modulus of the films containing low levels of sorbitol was ascribed to the antiplasticization of the films. Films prepared with sorbitol had lower water vapor permeability values but tended to be stiff and in some cases too brittle for tensile measurements. Sorbitol plasticization of the triticale protein films approached saturation at the plasticizer level of 50%. This work contributes to the understanding of the plasticizing-antiplasticizing effects of glycerol and sorbitol on properties of protein films and may be useful in the handling of these films as new food packaging systems, in accordance with the specific requirements of potential users. © 2013.

Effects of In Vivo Exposure to Roundup® on Immune System of Caiman latirostris. Latorre, María Agustina; López González, Evelyn Cecilia; Larriera, Alejandro; Siroski, Pablo Ariel; Poletta, Gisela Laura The present study aimed to evaluate the effect of Roundup® (RU, glyphosate-based formulation) on some parameters of the immune system and growth of Caiman latirostris. Seventy-two caimans (20-day-old) from Proyecto Yacaré (Gob. Santa Fe/MUPCN) were used. Two groups were exposed for 2 months to different concentrations of RU (11 or 21 mg/L; taking into account the concentration recommended for its application in the field), while one group was maintained as control. The RU concentration was progressively decreased through the exposure period to simulate glyphosate degradation in water. Animals were measured and weighed at the beginning and end of the experiment, and blood samples taken after exposure to determine total and differential white blood cell (WBC) counts as well as total protein concentration (TPC), and for performing protein electrophoresis. The results showed that, compared against control hosts, there was a decrease in WBC counts, a higher percentage of heterophils, a higher TPC (with a low percentage of F2 protein fraction), and a negative effect on growth in the young caimans exposed to RU. These results demonstrate that in vivo exposure to RU induced alterations in the selected immune parameters, plasma proteins, and growth of caimans, thereby providing relevant information about the effects of this type of pesticide in this important species in the Argentinian wetlands.

La empresa automotriz IASFSA en Santa Fe. Características de una experiencia en los márgenes (1959-1969) Vicentin, Enzo Oscar La industria automotriz en Argentina experimentó significativos cambios hacia finales de la década de 1950. Dentro de la nueva conformación que va adquiriendo el sector durante los ´60, este trabajo centra su interés en IASFSA, una empresa en la que la firma alemana DKW se asoció con inversionistas locales para producir automotores de la marca Auto Union. Esta empresa que se instaló en la provincia de Santa Fe, participó en el mercado hasta 1969, fabricó cerca de 33000 automotores y llegó a emplear a 1500 trabajadores, transformándose en una de las industrias más importantes de la región central de la provincia. A través de documentos de la propia empresa, entrevistas a ex trabajadores, legislación nacional y provincial de promoción industrial, revistas y periódicos de la época y bibliografía específica sobre la industria automotriz, el trabajo busca describir las distintas etapas de IASFSA desde su radicación hasta su crisis definitiva cerrada con la venta de su planta industrial a Fiat. En este marco, intentamos argumentar que aunque IASFSA siguió un patrón de comportamiento común a otras empresas del sector, algunas características específicas relacionadas a su ubicación geográfica, a la composición de su conducción y a su trayectoria en el mercado, hicieron de esta empresa una experiencia singular dentro de la industria automotriz en la década del ´60.

Ovarian localization of 11β-hydroxysteroid dehydrogenase (11βHSD): Effects of ACTH stimulation and its relationship with bovine cystic ovarian disease Amweg, Ayelen Noelia; Salvetti, Natalia Raquel; Stangaferro, M.L.; Paredes, A.H.; Lara, H.H.; Rodríguez, Fernanda Mariel; Ortega, Hugo Hector Cystic ovarian disease (COD) is an important cause of infertility in cattle, and ACTH has been involved in regulatory mechanisms related to ovarian function associated with ovulation, steroidogenesis, and luteal function. Here, we examined the localization of 11β-hydroxysteroid dehydrogenase type 1 (11βHSD1) and 11βHSD2 proteins in the ovary of healthy cows and animals with spontaneous and ACTH-induced COD and the invitro response of the follicular wall exposed to ACTH. After stimulation by ACTH, we documented changes in 11βHSD expression and cortisol secretion by the follicular wall of large antral and follicular cysts. Follicular cysts showed a higher constitutive expression of both enzymes, whereas ACTH induced an increase in 11βHSD1 in tertiary follicles and follicular cysts and a decrease in 11βHSD2 in follicular cysts. Moderate expression of 11βHSD1 was observed by immunohistochemistry in granulosa of control animals, with an increase (P < 0.05) from primary to secondary, tertiary, and atretic follicles. The level of immunostaining in theca interna was lower than that in granulosa. The expression of 11βHSD2 was lower in the granulosa of primary follicles than in that of secondary, tertiary, and atretic follicles and was lower in the theca interna than in the granulosa. In ACTH-induced and spontaneously occurring follicular cysts, differences from controls were observed only in the expression of 11βHSD1 in the granulosa, being higher (P < 0.05) than in tertiary follicles. These findings indicate that follicular cysts may be exposed to high local concentrations of active glucocorticoids and indicate a local role for cortisol in COD pathogenesis and in regulatory mechanisms of ovarian function.

Possible origin of polymorphism for chromosome number in the assassin bug Zelurus femoralis longispinis (Reduviidae: Reduviinae) Poggio, María Georgina; Provecho, Yael Mariana; Papeschi, Alba Graciela; Bressa, Maria Jose In this study, we analysed a population of Zelurus femoralis longispinis polymorphic for chromosomal number. The fundamental karyotype of this subspecies is 2n = 22 = 20A + XY (male), but individuals with 2n = 23 = 20A + XY + extra chromosome have been found at high frequency and collected at different time periods. We examined male meiotic behaviour, average length as percentage of the sex chromosomes, the content, distribution and composition of heterochromatin, and the number and location of ribosomal DNA in the two cytotypes found. The meiotic behaviour of the extra chromosome was highly regular and similar to that of sex chromosomes. The average length of the sex chromosomes in individuals not carrying the extra chromosome was significantly greater than in those carrying it. The results support a hypothesis that the extra chromosome might have originated by fragmentation of the original X chromosome into two unequal-sized chromosomes (X1 and X2), leading to an X1X2Y multiple system. Maintenance of the polymorphism with time appears to indicate that the new chromosomal variant is neutral or at least not detrimental, or that it could be selectively advantageous. This polymorphic population represents direct evidence of a multiple sex chromosome system originating through fragmentation of a single X in Reduviidae as well as in Heteroptera.