Classical membrane progesterone receptors in murine mammary carcinomas: agonistic effects of progestins and RU-486 mediating rapid non-genomic effects.
Bottino, Maria Cecilia; Cerliani, Juan Pablo; Rojas, Paola Andrea; Giulianelli, Sebastian Jesus; Soldati, Rocío; Mondillo, Carolina; Gorostiaga, Maria Alicia; Pignataro, Omar Pedro; Calvo, Juan Carlos; Gutkind, Silvio J.; Amornphimoltham, Panomwat; Molinolo, Alfredo A.; Luthy, Isabel Alicia; Lanari, Claudia Lee Malvina
In this article, we demonstrate the expression of functional progesterone binding sites at the cell membrane in murine mammary carcinomas that are stimulated by progestins and inhibited by antiprogestins. Using confocal immunofluorescence, ligand binding and cell compartment-specific western blots, we were able to identify the presence of the classical progesterone receptors. Medroxyprogesterone acetate (MPA) and RU-486 (1 × 10(-11) and 1 × 10(-8) M) behaved as agonists activating extracellular signal-regulated kinases (ERKs) and progestin-regulated proteins, except for Cyclin D1 and Tissue factor which failed to increase with 1 × 10(-8) M RU-486, an experimental condition that allows PR to bind DNA. These results predicted a full agonist effect at low concentrations of RU-486. Accordingly, at concentrations lower than 1 × 10(-11) M, RU-486 increased cell proliferation in vitro. This effect was abolished by incubation with the ERK kinase inhibitor PD 98059 or by OH-tamoxifen. In vivo, at a daily dose of 1.2 μg/kg body weight RU-486 increased tumor growth, whereas at 12 mg/kg induces tumor regression. Our results indicate that low concentrations of MPA and RU-486 induce similar agonistic non-genomic effects, whereas RU-486 at higher concentrations may inhibit cell proliferation by genomic-induced effects. This suggests that RU-486 should be therapeutically administered at doses high enough to guarantee its genomic inhibitory effect.
Transient simulation of a storage floor with a heating/cooling parallel pipe system
Flores Larsen, Silvana Elinor; Filippin, Maria Celina; Lesino, Graciela
The exact 2-D transient solution of a slab with an embedded array of parallel circular pipes for heating/cooling is developed. The boundary and initial conditions are: constant temperature at the pipe surface, upper slab surface subjected to convection heat transfer, thermal insulation at the slab bottom, and constant initial temperature. The analytical solution of the transient bi-dimensional problem is obtained together with the fluid temperature. A calculation example is analysed at the end of the paper to enlighten practical issues appearing in the computation of the analytical solution.
A robust clustering method for detection of abnormal situations in a process with multiple steady-state operation modes
Maestri, Mauricio Leonardo; Farall, Rodolfo Andres; Groisman, Pablo Jose; Cassanello, Miryan; Horowitz, Gabriel Ignacio
Many classical multivariate statistical process monitoring (MSPM) techniques assume normal distribution of the data and independence of the samples. Very often, these assumptions do not hold for real industrial chemical processes, where multiple plant operating modes lead to multiple nominal operation regions. MSPM techniques that do not take account of this fact show increased false alarm and missing alarm rates. In this work, a simple fault detection tool based on a robust clustering technique is implemented to detect abnormal situations in an industrial installation with multiple operation modes. The tool is applied to three case studies: (i) a two-dimensional toy example, (ii) a realistic simulation usually used as a benchmark example, known as the Tennessee?Eastman Process, and (iii) real data from a methanol plant. The clustering technique on which the tool relies assumes that the observations come from multiple populations with a common covariance matrix (i.e., the same underlying physical relations). The clustering technique is also capable of coping with a certain percentage of outliers, thus avoiding the need of extensive preprocessing of the data. Moreover, improvements in detection capacity are found when comparing the results to those obtained with standard methodologies. Hence, the feasibility of implementing fault detection tools based on this technique in the field of chemical industrial processes is discussed.
Digital Closed-Loop High-Speed Thyristor Firing System for Line-Commutated Converters
Maestri, Sebastian Oscar; Benedetti, Mario; Uicich, Gustavo Cesar; Gomez Costa, Jose Luis
This report presents the implementation of an all-digital high-speed closed-loop thyristor firing system based on the Cassel technique. Different aspects associated to digital implementations, like sampling frequency, synchronism and finite word-length are analyzed. Experimental results obtained on a CERN GEREG crate are presented.
¿Cómo tratan los psiquiatras argentinos la depresión bipolar? Encuesta a una muestra de 359 psiquiatras acerca de sus hábitos prescriptivos para el tratamiento farmacológico; How do argentinean psychiatrists treat bipolar depression?
Mazaira, Silvina; Leiderman, Eduardo A.; Nemirovsky, Martín; Vigo, Daniel Eduardo; Wikinski, Silvia Ines
Se presentan los resultados de una encuesta realizada a una muestra de 359 psiquiatras argentinos en el marco del Congreso Nacional de Psiquiatría llevado a cabo en la Ciudad Autónoma de Buenos Aires entre el 26 y 29 de septiembre de 2007. El objetivo de la encuesta fue estudiar los hábitos prescriptivos de los psiquiatras asistentes en lo referente al tratamiento de la depresión bipolar. La discusión se centra en la comparación de las respuestas obtenidas con las conductas de tratamiento sugeridas en las principales guías, consensos y autores de referencia. Las diferencias halladas señalan una distancia observada con frecuencia entre las guías y consenso de tratamiento (realizados en base a poblaciones de pacientes seleccionadas para los ensayos clínicos controlados) y el mundo real de la práctica clínica cotidiana a la que se enfrenta el psiquiatra.; We show the results of a survey on bipolar depression treatment using a sample of 359 argentine psychiatrists in the context of The National Psychiatry Congress that took place in the City of Buenos Aires, between September 26th and 29th , 2007. The objective was to study the attendant psychiatrists’s prescribing habits in the treatment of bipolar depression. The discussion is based on the comparison between the answers and the recommendations taken from the main consensus, guidelines and from articles published by experts. The differences found point to the distance often present between guidelines and expert consensus series (based on patients meeting the strict criteria used in randomized controlled studies) on one hand, and a clinician’s everyday real world practice, on the other hand.
Taxonomic status of Apterodytes ictus AMEGHINO, 1901 (Aves; Sphenisciformes) from the early miocene of patagonia, Argentina
Acosta Hospitaleche, Carolina Ileana Alicia
A proximal end of a humerus collected by C. AMEGHINO was designated as the holotype of Apterodytes ictus AMEGHINO, 1901 in the monotypic genus Apterodytes AMEGHINO, 1901. Later, AMEGHINO (1905) transferred this species to the new genus Palaeoapterodytes AMEGHINO, 1905. The validity and affinity of this species has been discussed controversial, not only on account of the poor preservation of the material, but also because of the characters used in its diagnosis and description. A systematic revision of Aptenodytes ictus (AMEGHINO, 1901) is presented. This is a proximal end of a right humerus strongly weathered that was interpreted as a complete humerus with an unique morphology. The characters included in the original diagnosis and the description are inadequate to compare with those of other species as they are based mainly on the assumption of the atrophy of a humerus that is in fact fractured and incomplete. Its morphology allows its confidant assignment to the family Spheniscidae, although it is not well enough preserved to assign it to any known genus. Therefore, this fossil is not appropriate to found a species on and Palaeoapterodytes ictus (AMEGHINO, 1901) must be considered as a nomen dubium.
Rheological properties of a two phase lipid monolayer at the air/water interface: Effect of the composition of the mixture
Wilke, Natalia; Vega Mercado, Franco; Maggio, Bruno
Many biologically relevant monolayers show coexistence of discrete domains of a long-range ordered condensed phase dispersed in a continuous, disordered, liquid-expanded phase. In this work, we determined the viscous and elastic components of the compressibility modulus and the shear viscosity of monolayers exhibiting phase coexistence with the aim at elucidating the contribution of each phase to the observed monolayer mechanical properties. To this purpose, mixed monolayers with different proportions of distearoylphosphatidylcholine (DSPC) and dimyristoylphosphatidylcholine (DMPC) were prepared and their rheological properties were analyzed. The relationship between the phase diagram of the mixture at 10 mN m-1 and the rheological properties was studied. We found that the monolayer shear viscosity is highly dependent on the presence of domains and on the domain density. In turn, the monolayer compressibility is only influenced by the presence of domains for high domain densities. For monolayers that look homogeneous on the micrometer scale (DSPC amount lower that 23 mol %), all the analyzed rheological properties remain similar to those observed for pure DMPC monolayers, indicating that in this proportion range the DSPC molecules contribute as DMPC to the surface rheology in spite of having hydrocarbon chains four carbons longer.
Contratos de estado, inversión extranjera y derecho internacional público
Castillo Argañarás, Luis Fernando
El objetivo de éste artículo es responder al siguiente interrogante: ¿Es posible aplicar Derecho Internacional Público a los contratos de Estado? En ese sentido, se analizará la naturaleza jurídica de estos contratos y luego la vinculación de éste tipo de instrumentos jurídicos con el Derecho Internacional Público. También se considerará el arbitraje internacional.; O objetivo deste artigo é responder à seguinte questão: É possível aplicar o Direito Internacional Público a contratos do Estado. Nesse sentido, vamos analisar a natureza jurídica dos contratos do Estado e, a seguir, relacionar estes tipos de contratos com o Direito Internacional. Também ser considerada uma arbitragem internacional.; The purpose of this paper is to answer the following question: Is it possible to apply Public International Law to State Contracts? In this sense, the legal nature of State contracts will be analysed and then the link between Public International Law and this type of contracts will be established. International arbitration will be considered.
Experiencias y discursos sobre organización política y laboral de las y los jóvenes. Un acercamiento histórico-etnográfico a los procesos de socialización-apropiación contemporáneos
Scarfó, Gabriela Fernanda; Enrique, Iara Nuria
El objetivo de este artículo consiste en analizar, desde un enfoque histórico-antropológico, la particularidad de algunas experiencias y reflexiones relativas a la vida política y laboral de las y los jóvenes adolescentes, en dos contextos de socialización diferenciados: una organización no gubernamental dedicada a la formación de la juventud en el mundo del trabajo y una organización de segundo grado que procura aglutinar al llamado movimiento estudiantil secundario en la Ciudad de Buenos Aires.; The aim of this paper is to analyze from a historical-anthropological approach the particularity of some experiences and reflections relative to the political life and the world of the work of the young people in two different contexts of socialization: an non-governmental organization dedicated to the education of young people in the world of work and an organization of the second degree that tries to agglutinate the so called student secondary movement in the City of Buenos Aires.
Evaluación y calidad en los programas y cursos online en la enseñanza superior; Evaluation and quality at programmes and specific courses in higher education
Constantino, Gustavo Daniel; Llull, Laura
La Educación a Distancia (EAD) ha sido siempre considerada con cierto escepticismo en cuanto a la calidad de los programas en contraste con la enseñanza en presencia. La EAD basada en redes telemáticas ha logrado disminuir el recelo, pero no lo ha hecho desaparecer.La evaluación, como aspecto crítico de la calidad, hasta hoy no ha sido objeto de un examen profundo en relación a los nuevos contextos y en general se trasvasan los sistemas de evaluación convencionales y propios de la formación en presencia a los entornos online. Sin embargo, existe una intuición extendida en que tales sistemas no son del todo congruentes con la naturaleza de la enseñanza y del aprendizaje en comunidades virtuales, aspecto que ha sido particularmente sensible en el caso del Proyecto Alfa-Miforcal, ilustrándose con un par de ejemplos. El escenario de la educación online está cambiando dramáticamente con el surgimiento de nuevas formas de enseñar y aprender, pasando de modelos de reproducción de conocimientos a modelos del aprendizaje colaborativo y conocimiento compartido centrados en la actividad del estudiante en Comunidades Virtuales de Aprendizaje. En estas se puede llegar a un grado de interacción en el que la evaluación formativa alcanza niveles semejantes a los de la mejor orientación del aprendizaje en presencia.; Distance Education has been always considered with certain skepticism for the quality of the programs in contrast with the education in presence. The distance education based on virtual networks has managed to diminish the mistrust, but it has not made it disappear. The evaluation, as critical aspect of the quality, up to today has not been an object of a deep examination in relation to the new contexts, which implies that the conventional and proper systems of evaluation of the formation in presence are applied to the environments online. Nevertheless, there exists a widespread intuition in which such systems do not correspond completely to the nature of the education and of learning in virtual communities, Aspect that has been particularly sensitive in case of the Project Alfa-Miforcal, illustrated with a pair of examples. The scenario of the education online is changing dramatically with the emergence of new ways of teaching and of learning, going on from models of reproduction of knowledge to models of collaborative learning and shared knowledge focused on the activity of the student in Learning Virtual Communities. In these, it is possible to come to a grade of interaction in which the formative evaluation reaches similar levels to those of the best orientation of learning in presence.
El entorno sudamericano y su significado en la política exterior de los gobiernos de Duhalde y Kirchner
Torres, Miguel Agustín
La crisis institucional y socioeconómica que afectó a Argentina a fines de 2001 y principios de 2002 no solo implicó el agotamiento del modelo neoliberal implementado desde el comienzo de la década del noventa sino que también significó la posibilidad de revisar el esquema de inserción internacional que lo complementó. Esta reformulación de la política exterior incluía la oportunidad de replantear los vínculos con los países sudamericano y el rol del país dentro de MERCOSUR. En este aporte se analiza el significado que se asignó a las relaciones con los actores subregionales y a MERCOSUR en la política y exterior argentina luego de la crisis del 2001.; A crise institucional e sócio-econômicos que a Argentina sofreu no final de 2001 e início de 2002, não só representou o esgotamento do modelo neoliberal aplicado desde o início dos anos noventa, também significou a possibilidade de rever o esquema de inserção internacional que acompanhou esse modelo. Esta reformulação da política externa incluída a oportunidade de repensar os laços com os países da América do Sul eo papel do país no Mercosul. Esta contribuição analisa os significados atribuídos às relações com os atores subregionais e ao Mercosul na política externa da Argentina após a crise de 2001.
Screening for antifungal activity in plants from central Argentina
Palacios, Sara Maria; Ruiz, Gustavo; Carpinella, Maria Cecilia
Ethanolic extracts from aerial parts of 71 native plants from Argentina were tested by bioautography on Thin Layer Chromatography (TLC) for their antifungal effects against pathogenic Fusarium verticillioides. The extracts of Aristolochia argentina (Aristolochiaceae), Flourensia oolepis (Asteraceae), Gaillardia megapotamica (Asteraceae), Salvia cuspidata (Lamiaceae) and Trichocline reptans (Asteraceae) at Minimum Inhibitory Concentrations (MICs) of 0.03 to 0.12 mg/spot were highly effective in inhibiting the fungal growth followed by extracts from Baccharis artemisioides (Asteraceae), Baccharis salicifolia (Asteraceae), Dalea elegans (Fabaceae), Heterothalamus alienus (Asteraceae), Lepechinia floribunda (Lamiaceae), Vernonia nudiflora (Asteraceae) and Zanthoxylum coco (Rutaceae) at MICs of 0.25 - 0.50 mg/spot. While, F. oolepis, T. reptans and A. argentina extracts proved most potent, with MICs of 0.03, 0.03 and 0.06 mg/spot, respectively. Further studies are required with extracts of the most active species in bioguided assay isolation to obtain new molecules with potent antifungal properties to control harmful fungi such as F. verticillioides.
Maximal operators, Riesz transforms and Littlewood–Paley functions associated with Bessel operators on BMO
Betancor, J.J.; Chicco Ruiz, Anibal Leonardo; Fariña, J.C.; Rodríguez-Mesa, L.
In this paper we study boundedness properties of certain harmonic analysis operators (maximal operators for heat and Poisson semigroups, Riesz transforms and Littlewood–Paley g-functions) associated with Bessel operators, on the space BMOo(R) that consists of the odd functions with bounded mean oscillation on R.
On state estimation in electric drives
Leon, Enrique Andres; Solsona, Jorge Alberto
This paper deals with state estimation in electric drives. On one hand a nonlinear observer is designed, whereas on the other hand the speed state is estimated by using the dirty derivative from the position measured. The dirty derivative is an approximate version of the perfect derivative which introduces an estimation error few times analyzed in drive applications. For this reason, our proposal in this work consists in illustrating several aspects on the performance of the dirty derivator in presence of both model uncertainties and noisy measurements. To this end, a case study is introduced. The case study considers rotor speed estimation in a permanent magnet stepper motor, by assuming that rotor position and electrical variables are measured. In addition, this paper presents comments about the connection between dirty derivators and observers, and advantages and disadvantages of both techniques are also remarked.
Phage adsorption to Lactobacillus plantarum: influence of physiological and environmental factors.
Briggiler Marcó, Mariángeles; Reinheimer, Jorge Alberto; Quiberoni, Andrea del Lujan
Bacteriophage infection of lactic acid bacteria (LAB) constitutes one of the major problems in the dairy industry, causing economic losses and a constant risk of low quality and/or unsafe foods. The first step in the phage biology is the adsorption on the host cell surface. In a previous study, a remarkable thermal, chemical and photocatalytic resistance was demonstrated by four phages of Lactobacillus plantarum (ATCC 8014-B1, ATCC 8014-B2, FAGK1 and FAGK2). In the present work, these phages were used to characterize the adsorption process on L. plantarum ATCC 8014. Clearly, the characterization of this process could increase the possibilities of design useful strategies in order to prevent phage infections. The influence of Ca(2+), temperature, pH and physiological cell state on phage adsorption was investigated. Burst sizes of phages ATCC 8014-B1 and ATCC 8014-B2 were 60 and 83 PFU/infective centre, respectively. The four phages exhibited a high infectivity even at pH 4 and pH 11. Calcium or magnesium ions were not indispensable for cell lysis and plaque formation, and more than 99% of phage particles were adsorbed either in the presence or absence of Ca(2+), after 15 min at 37 degrees C. Phage adsorption was only partially affected at 50 degrees C, while reached its maximum between 30 and 42 degrees C. The highest adsorption values (99.9%) were observed from pH 5 to 7, after 30 min at 37 degrees C. Adsorption rates decreased after the thermal inactivation of cells, though, when 20 microg/ml of chloramphenicol was used, adsorption values were similar on treated and untreated cells. All these results showed that the adsorption process was only partially affected by a few conditions: thermally killed host cells, an incubation temperature of 50 degrees C and pH values of 9 and 10. Nevertheless, and unfortunately, those conditions are not commonly applied during fermented food manufacturing, thus restricting highly the application of strategies currently available to reduce phage infections in industrial environments. This work also contributes to increase the currently knowledge on the biological aspects of L. plantarum bacteriophages.
Recorrido sobre las lenguas del Chaco y los aportes a la investigación lingüística
Golluscio, Lucia Angela; Vidal, Alejandra Silvia
El Chaco es una de las regiones más ricas de América del Sur, no sólo desde el punto de vista ecológico, sino en términos de su diversidad etnolingüística. Este artículo ofrece primero un panorama actualizado sobre las lenguas chaqueñas y su clasificación genealógica así como un estado del arte de las obras publicadas sobre las lenguas del Chaco argentino. Después de reseñar los estudios sobre sintaxis en las lenguas chaqueñas anteriores a este volumen de Amerindia, las autoras se centran en los planteos teóricos que emergen del estudio de la cláusula y las relaciones interclausales en esta área lingüística, haciendo hincapié en los sistemas de alineamiento, las clases de palabras, sus límites y superposiciones, la relacionalidad de los sustantivos, los distintos tipos de cláusulas y de predicados, los procesos de combinación de verbos y de enlace entre cláusulas a nivel oracional y discursivo. Por último, pasan revista a los aspectos en los cuales los trabajos compilados contribuyen a la discusión y profundización de todos esos temas.
Density and habitat use at different spatial scales of a guanaco population (Lama guanicoe) in the Monte desert of Argentina
Acebes, Pablo; Traba, Juan; Malo, Juan E.; Ovejero Aguilar, Ramiro Jose Antonio; Borghi, Carlos Eduardo
The first density estimates of a peripheral guanaco population and its habitat use at different spatial scales are presented for a protected area of Monte desert, Argentina. Transects were surveyed in the wet and dry seasons of 2005. All guanaco herds observed during systematic surveys using roads and tracks were GPS located and their habitat use was identified. Herd size differed significantly between the dry and wet seasons. Population densities differed between wet (0.10-0.12 individuals/km2) and dry seasons (0.60-0.75 individuals/km2). The population estimates ranged from 75 individuals (dry season) to 388 individuals (wet season). Guanacos showed differential habitat use, the first determinant being abiotic factors, such as topography, soil characteristics or microclimate conditions, animals being detected in rougher rocky substrata in the dry season and in open flat terrain in the wet season, followed by a mesoscale selection defined by plant communities. At the latter scale, guanaco preferentially used mixed creosote bushland and saltbush more intensively during the wet season, and open scrub and columnar-cactus slopes in the dry season. The estimated population of this protected area was small but its population density was within the range of other populations and was relatively high for this dry and unproductive area.
Cross-habitat variation in the phenology of a colonial spider: Insights from a reciprocal transplant study
Fernández Campón, María Florencia
In species with widespread distribution, populations found in markedly different environments can show differences in developmental traits. This, in time, can have an effect on reproductive success. Sources of variation in developmental traits can be genetic or environmentally induced. I examined the relationship between environmental and genetic influences on juvenile development in populations of the colonial spider, Parawixia bistriata, located at sites with different moisture regimes and associated environmental variables (e.g., prey availability). It was expected that individuals from different populations would show differences in developmental traits and that those differences will be associated with lower reproductive success at dry sites. I recorded the phenology and developmental traits of native and transplanted individuals in the field and estimated reproductive success based on clutch size. Colonies from wet versus dry sites showed different phenologies, with individuals at dry sites maturing later. Transplant results suggest plasticity in instar duration caused by environmental effects. Despite differences in resources and spider phenology, clutch sizes of native dry and wet populations were similar. Transplanted individuals, however, were differentially affected. Transplants from wet to dry sites (WD) showed lower growth rates and smaller clutches, whereas transplants from dry to wet sites had larger clutch sizes than in native habitat. Delayed maturation and failure to reproduce in WD individuals is associated with a lower tendency to capture prey in groups and less aggressive interactions during prey capture. Thus, despite negative environmental effects on development, dry native individuals have evolved non-developmental traits that allow successful reproduction.
Maximal operators, Riesz transforms and Littlewood-Paley functions associated with Bessel operators on BMO
Betancor, J. J.; Chicco Ruiz, Anibal Leonardo; Fariña, J. C.; Rodriguez Mesa, L.
In this paper we study boundedness properties of certain harmonic analysis operators (maximal operators for heat and Poisson semigroups, Riesz transforms and Littlewood– Paley g-functions) associated with Bessel operators, on the space BMOo(R) that consists of the odd functions with bounded mean oscillation on R.
