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.
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.
Relational databases as a massive information source for defeasible argumentation
Deagustini, Cristhian Ariel David; Fulladoza Dalibón, Santiago Emanuel; Gottifredi, Sebastián; Falappa, Marcelo Alejandro; Chesñevar, Carlos Iván; Simari, Guillermo Ricardo
Argumentation provides a sophisticated yet powerful mechanism for the formalization of commonsense reasoning in knowledge-based systems, with application in many areas of Artificial Intelligence. Nowadays, most argumentation systems build their arguments on the basis of a single, fixed knowledge base, often under the form of a logic program as in Defeasible Logic Programming or in Assumption-Based Argumentation. Currently, adding new information to such programs requires a manual encoding, which is not feasible for many real-world environments which involve large amounts of data, usually conceptualized as relational databases. This paper presents a novel approach to compute arguments from premises obtained from relational databases, identifying several relevant aspects. In our setting, different databases can be updated by external, independent applications, leading to changes in the spectrum of available arguments. We present algorithms for integrating a database management system with an argument-based inference engine. Empirical results and running-time analysis associated with our approach show that it provides a powerful alternative for efficiently achieving massive argumentation, taking advantage of modern DBMS technologies. We contend that our proposal is significant for developing new architectures for knowledge-based applications, such as Decision Support Systems and Recommender Systems, using argumentation as the underlying inference model.
Mode I stress intensity factor for cracked thin-walled composite beams
Dotti, Franco Ezequiel; Cortínez, Víctor Hugo; Reguera, Florencia
In this paper, we present an analytical method to determine the mode I stress intensity factor for thin-walled beams made of laminated composites. The technique relies on the concept of crack surface widening energy release rate, which is expressed in terms of the G* integral and thin-walled beam theory. In the vicinity of the crack tip, a solution of the G* integral is obtained employing stress and displacement fields derived for materials with general orthotropy. The effect of warping is taken into account. This is a common feature in thin-walled beams which cannot be neglected, especially when flexural-torsional loads are present.The model shows a good agreement with finite element results. It is shown that, although the approaches developed for isotropic materials may be useful in the treatment of orthotropic problems, they may not yield good results for some typical lamination sequences.
La importancia de la aplicación de las buenas prácticas agrícolas y del Derecho Ambiental en el recurso del agua
Minaverry, Clara María; Gally de Minaverry, Teresa Adela
La creciente implementación de sistemas para el control, el aseguramiento, o la planificación de calidad evidencian que ésta se ha convertido en un arma competitiva de importancia para las organizaciones modernas.
SEPT10 expression in chronic lymphocytic leukemia. Correlation with clinical and biological prognostic factors
Travella, Ana Carolina; Panero, Julieta; Stanganelli, Carmen Graciela; Bezares, Raimundo F.; Slavutsky, Irma Rosa
Chronic lymphocytic leukemia (CLL) is characterized by a highly variable clinical course. Microarray studies allowed highlight genes differentially expressed in this pathology. In this study, we have evaluated the prognostic significance of SEPT10 expression in CLL patients. Results were correlated with immunoglobulin heavy-chain variable (IGHV) genes mutational status, genomic rearrangements and clinical parameters. SEPT10 mRNA levels were determined by quantitative real-time PCR in 70 newly diagnosed CLL patients consecutively referred to our Institution. A wide heterogeneity for SEPT10 expression was found. Gene upregulation was observed in 18.5% of cases. The univariate analysis showed a positive association between gen expression and platelet count (p < 0.0001) and a negative correlation with hemoglobin levels (p = 0.0094). Although no significant differences were observed, mean treatment free survival was shorter in patients with high expression (31 months) with respect to those with low mRNA levels (72 months). Cases with abnormal karyotypes had increased expression compared to those with normal karyotypes and no association between gene expression and FISH (fluorescence in situ hybridization) risk groups and IGHV mutational status was found. Cases using IGHV3-23 gene rearrangement had low SEPT10 expression. Our results showed an association between SEPT10 expression and features of adverse outcome but without independent prognostic value. The study of SEPT10 expression may be important for a better understanding of disease heterogeneity, adding further information to those provided by established prognostic factors.
Supermartensitic stainless steel deposits: shielding gas and post-weld heat treatment: detailed are the results as CO2 content in the shielding gas increased, plus the postweld heat treatment utilized in this work
Zappa Maidana, Norberto Sebastián; Svoboda, Hernán Gabriel; Surian, Estela Silvia
Welding supermartensitic stainless steel plays a crucial role in structural components, influencing their toughness and resistance to sulfide stress cracking. Postweld heat treatment (PWHT) adjusts the final properties of the weldments, bearing on microstructural evolution. The objective of this work was to study the effects of different shielding gas mixtures and PWHT on supermartensitic stainless steel allweld-metal properties. Three all-weld-metal test coupons were prepared according to standard ANSI/AWS A5.22:95, Specification for Stainless Steel Electrodes for Flux Cored Arc Welding and Stainless Steel Flux Cored Rods for Gas Tungsten Arc Welding, using a 1.2-mm-diameter tubular, metal-cored wire under Ar-5% He, Ar-2% CO2, and Ar-18% CO2 gas shielding mixtures in the flat position with a nominal heat input of 1 kJ mm–1. The PWHT used was 650°C for 15 min. All-weld metal chemical composition analysis, metallurgical characterization, hardness and tensile property measurements, and Charpy V-notch tests were carried out. It was found that as CO2 increased in the shielding gas C, O, and N contents increased as well as mechanical properties varied; hardness and ultimate tensile strength increased, and toughness decreased. The PWHT improved toughness. Technological property of the consumable was also studied.
La transmisión textual de la traducción de la Divina Comedia (1515): ¿del impreso al manuscrito?; The textual transmission of the Castilian translation of the Divine Comedy (1515): From print to manuscript?
Hamlin, Cinthia Maria
El texto de la primera traducción impresa de la Divina Comedia (Burgos, 1515) se conserva sólo en un manuscrito (HSA, B2183), considerado hasta ahora el texto de base que se usó en la imprenta. Este tema ha sido poco discutido, tal vez por la falta de un estudio minucioso que aborde el manuscrito y los problemas de su transmisión textual. En el presente trabajo, intentaremos problematizar la relación de filiación que se ha dado por sentada entre el testimonio manuscrito y el impreso, a través de un cotejo que se enfocará especialmente en los versos enmendados y en las variantes tanto léxicas como sintagmáticas.