Los conceptos y las cosas: Evolución y alcance de la teoría vitalista del concepto Cherniavsky, Axel Forma eterna e inmutable, representación del entendimiento, síntesis del ser y de la esencia, el concepto parece recibir una definición distinta según la filosofía que lo considere. No obstante, un esfuerzo común parece aunar las filosofías de Spinoza, Bergson y Deleuze, que de distintas maneras se proclaman vitalistas. Consiste justamente en insuflarle al concepto el máximo de vida, una plena realidad. Se determinarán en cada caso cuáles son las características de esta vitalidad, qué es lo que al concepto le confiere plena realidad, para finalmente evaluar las ventajas y los riesgos del nuevo concepto de concepto.; Eternal and unchangeable Form, representation of the intellect, synthesis of being and essence, the concept seems to admit a di#erent de!nition in each philosophy. Nevertheless, the systems of Spinoza, Bergson and Deleuze -- all vitalists but in di#erent ways-- seem to converge on one single common e#ort. It consists precisely in infusing the concept with the maximum of vitality, a full reality. We will determine in each case which are the notes that compose this vitality, what confers the concept an absolute reality, so that we can evaluate the advantages and risks of the new concept of concept.

Lo simbólico y lo real en la definición de la realidad médica: Notas sobre las potencialidades heurísticas del concepto de experiencia Bordes, Mariana Argentina El artículo tiene como punto de partida una de las tensiones epistemológicas más marcadas que atraviesan a la producción de conocimiento en el seno de las ciencias sociales: el dualismo entre las creencias y el conocimiento objetivamente fundado. Desde este horizonte de problemas, y centrándose particularmente en el campo de los estudios sobre el cuerpo y la experiencia en situaciones de enfermedad, el artículo tiene como objetivo dilucidar el modo en que la introducción del concepto de experiencia habilita a una lectura que permite trascender estas tensiones. En el primer apartado, el trabajo ahonda en los principales aportes brindados por los estudios que abordan la enfermedad desde una perspectiva fenomenológica. Mientras que en el segundo, se centra en las elaboraciones desarrolladas desde una perspectiva socio-antropológica, haciendo foco particularmente en autores como Lévi-Strauss, Clifford Geertz y Roger Abrahams. El trabajo concluye enfatizando la necesidad de abordar los fenómenos médicos sin recaer en un estudio de las distintas formas de aprehensión y organización de los procesos de padecimiento como lógicas diferenciadas de conocimiento (lo cual corre el riesgo de recaer en una lectura “idealista” que define estas lógicas como procesos de producción de significado, sin más) sino, por el contrario, dando cuenta de la eficacia concreta, las implicancias objetivas, que esas creencias ponen en juego de manera particular.

Stabilization and control of tie-line power flow of microgrid including wind generation by distributed energy storage Molina, Marcelo Gustavo; Mercado, Pedro Enrique High penetration of wind generation in electrical microgrids causes fluctuations of tie-line power flow and significantly affects the power system operation. This can lead to severe problems, such as system frequency oscillations, and/or violations of power lines capability. With proper control, a distribution static synchronous compensator (DSTATCOM) integrated with superconducting magnetic energy storage (SMES) is able to significantly enhance the dynamic security of the power system. This paper proposes the use of a SMES system in combination with a DSTATCOM as effective distributed energy storage (DES) for stabilization and control of the tie-line power flow of microgrids incorporating wind generation. A new detailed model of the integrated DSTATCOM-SMES device is derived and a novel three-level control scheme is designed. The dynamic performance of the proposed control schemes is fully validated using MATLAB/Simulink. © 2009 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.

Interannual variations in the Zonal Asymmetry of the subpolar latitudes Total Ozone Column during the Austral Spring Agosta Scarel, Eduardo Andres; Canziani, Pablo Osvaldo The Southern Hemisphere midlatitude Total Ozone Column (TOC) shows a “horseshoe” like structure with a minimum which appears to have two preferential extreme positions during October: one, near southern South America, the other, near the Greenwich Meridian approximately. The interannual zonal ozone asymmetry exists independently of the variations induced by the 11-year solar cycle, the Quasi-Biennial Oscillation (QBO) and planetary wave activity inducing the Brewer-Dobson circulation. The classification and climatological composition of these two extreme ozone-minimum positions allows for the observations of statistically significant patterns in geopotential height and zonal winds associated with the quasi-stationary wave 1, extending throughout lower stratosphere. The changes in the quasi-stationary wave 1 associated with the extreme TOC positions appear to have sinks and sources determining transient interactions between troposphere and the stratosphere. Thus, distinct climate states in the troposphere seem to be dynamically linked with the state of the stratosphere and ozone layer. The migration of the TOC trough from southern South America to the east during the 1990s can be related to changes in the troposphere/stratosphere coupling through changes in the Southern Annular Mode variability in spring.; La Columna Total de Ozono (CTO) de las latitudes medias del Hemisferio Sur muestra una estructura de “herradura” con un mínimo que muestra tener dos posiciones preferenciales extremas durante octubre: uno, en las cercanías del sur de Sudamérica, y el otro, cerca del meridiano de Greenwich. La asimetría zonal de ozono existe independientemente de las variaciones inducidas por el ciclo solar de 11 años, la Oscilación Cuasi-Bianual (QBO) y la actividad de onda planetaria asociada a la circulación de Brewer-Dobson. La clasificación y composición climatológica de estas dos situaciones longitudinalmente extremas de mínimo de ozono permite observar patrones estadísticamente significativos en geopotencial y vientos zonales asociados a una onda cuasi-estacionaria 1 que abarca la estratósfera inferior. Los cambios en la onda cuasi-estacionaria 1 asociados a las posiciones extremas de mínimo de ozono muestran tener fuentes y sumideros que determinan interacciones transientes entre la troposfera y la estratosfera. Así, estados climáticos distinguibles de la troposfera parecen estar dinámicamente vinculados con el estado de la estratosfera y la capa de ozono. La migración de la vaguada de CTO desde el sur de Sudamérica hacia el este durante la década de 1990 puede estar vinculada a cambios en la variabilidad del Modo Anular del Sur durante la primavera austral.

Renal Parenchyma Abnormalities in Infants With Dilating Vesicoureteral Reflux: Relation to Reflux Severity and Pressure at Onset Podestá, Miguel Luis; Castera, Roberto; Chappero, Lucas Purpose: We used 99mtechnetium dimercapto-succinic acid scans in infants to determine the relation between renal deformities and severity of primary dilating reflux. We also used videourodynamics to analyze the association between detrusor pressure at onset of reflux and degree of renal changes. Materials and Methods: A total of 20 patients (15 males) 0.10 to 1.3 years old (median 0.75) with grade III to V reflux underwent conventional filling videourodynamics. 99mTechnetium dimercapto-succinic acid scans were done 6 months after the last febrile urinary tract infection (median age 0.58 years). Results: Nine males and 1 female had bilateral refluxing ureters, and 10 patients had unilateral reflux (grade III in 10, IV in 11 and V in 9). Among the 30 refluxing ureters renal changes were present in 19 kidneys (63%). Prevalence of renal changes according to reflux grade III, IV and V was 40%, 63% and 89%, respectively (p <0.02). Reflux occurred in 13 patients (21 ureters) with detrusor pressure less than 10 cm water and in 7 (9) at 30 to 70 cm water (median 39.5). Renal changes were significantly more common in low pressure, low volume refluxing ureters (84.6%) compared to ureters refluxing at higher volumes and low pressure (37.5%, p <0.02). At higher pressure reflux renal deformities occurred in 55.5% of refluxing ureters (5 of 9). Five patients had renal function impairment (mean creatinine for age 0.92 mg/dl, range 0.60 to 1.53). Conclusions: High grade reflux and reflux occurring in the first half of bladder filling at low pressure are risk factors for renal changes in this cohort of infants.

In vitro assembly of the feline immunodeficiency virus Gag polyprotein Affranchino, Jose Luis; González, Silvia A. The retroviral Gag protein is the only viral product that is necessary for the assembly of virions in mammalian cells. We have established an in vitro assembly system to study the assembly properties of purified feline immunodeficiency virus (FIV) Gag protein expressed in bacteria. Under fully defined conditions, the FIV Gag protein assembles into spherical particles of 33. nm in diameter which are morphologically similar to authentic immature particles, albeit smaller than virions. The in vitro assembly of FIV Gag into particles was found to be resistant to the addition of Triton X-100 and required the presence of RNA. Notably, we found that an amino acid substitution in the nucleocapsid domain of Gag that impairs RNA binding and blocks virion production in vivo, also abrogates Gag assembly in vitro. The development of an in vitro assembly system for FIV Gag protein will facilitate the study of the mechanisms by which this protein assembles into immature particles.

"Patrimonio, identidad y desarrollo": Breve ensayo sobre los procesos de valoración, apropiación y usos del patrimonio cultural Adad, Ludmila El presente ensayo tiene como antecedente principal el trabajo de reflexión teórica y análisis bibliográfico vinculado al Proyecto de Tesis Doctoral “Cuando el patrimonio se convierte en un recurso”. Las acciones tendientes a la valoración, apropiación y usos del patrimonio cultural en el Partido de Olavarría”. Aquí se plantean claves para la indagación sobre cuestiones que hacen a los procesos de "patrimonialización" y "usos del patrimonio", atendiendo a cuestiones tales, como la percepción y los usos diversos de los bienes culturales, entre ellos su “uso social”, considerando que el patrimonio no puede ser concebido como una manifestación ajena a la organización material propia que hace posible su existencia.; This essay has as a previous work a theoretical analysis related to a PhD Project tittled "When heritage becomes a resource. Actions aimed at the valuation, ownership and use of cultural heritage in the Olavarría District (Argentina). Some keys will be presented here about issues that make the processes of "patrimonialization" and "uses of heritage”, encompassing issues such as perception and uses of cultural property, including the "social use", considering that heritage is not to be conceived as an external demonstration of the material organization itself, that makes it´s existence possible.

New limonene-hybrid derivatives with anti-T. cruzi activity Alvarez, Guzmán; Gerpe, Alejandra; Benitez, Diego; Garibotto, Francisco Matías; Zacchino, Susana Alicia Stella; Graebin, Cedric Stephan; Gomes da Rosa, Ricardo; Eifler Lima, Vera; González, Mercedes; Cerecetto, Hugo The development of hybrid compounds containing limonene- and recognized anti-T. cruzi-heterocycle-frameworks is described. The six new compounds displayed broad antitrypanosomal activities having 5-nitrofuran and 5-nitroindazole derivatives, the best profiles. In addition, a 5-nitroindazole derivative evaluated against a panel of fungi exhibited relevant activities. Knowing that free-radical-production operates as one of the mechanisms of action on these heterocycles, we studied a potential extra-mechanism, membrane-sterols changes. Non-relevant T. cruzi squalene accumulation was observed for any of the tested hybrid-limonene derivatives. © 2010 Bentham Science Publishers Ltd.

Cómplices o Amigos: Dos Modelos de Sociedad en el Discurso de Étienne de la Boétie Tizziani, Manuel El Discurso sobre la servidumbre voluntaria (1548) de Étienne de La Boétie se erige sobre una dicotomía entre dos conceptos antagónicos: el de amistad por un lado, el de complicidad por otro. En este artículo nos proponemos reconstruir esa antagonía, para comprender cómo, sobre ella, se fundan, a ojos del autor, también dos modelos de sociedad antitéticos: una depravada por la avaricia y el egoísmo; la otra, caracterizada por la amistad, el libre uso de la palabra, y la igualdad de derechos.

Los escépticos modernos y la génesis del cogito cartesiano Bahr, Fernando Anibal En su respuesta a las objeciones que el jesuita Bourdin dirigiera a las Meditaciones metafísicas, Descartes dejó en claro que los escépticos a los que se proponía refutar formaban parte de una ?secta? en crecimiento y atea, esto es, un peligro filosófico y político vigente. La alusión apuntaba seguramente al "libertinismo erudito", cuyo representante escéptico más destacado fue François de La Mothe Le Vayer. Para ratificar esta pertenencia de la metafísica cartesiana a un debate donde se entendía que las bases mismas de la convivencia social estaban en juego, en este artículo presentamos algunos de los diálogos escritos por Le Vayer y luego comparamos esa versión del escepticismo con la que Descartes ofrece en las Meditaciones algunos años después.

Suitability of buttermilk for fermentation with Lactobacillus helveticus and production of a functional peptide-enriched powder by spray-drying Burns, Patricia Graciela; Molinari, F.; Beccaria, A.; Paez, Roxana; Meinardi, Carlos Alberto; Reinheimer, Jorge Alberto; Vinderola, Celso Gabriel Aim: To ferment buttermilk, a low-cost by-product of the manufacture of butter, with a proteolytic strain of Lactobacillus helveticus, to enhance its value by the production of a functional peptide-enriched powder. Methods and Results: Buttermilk was fermented with Lact. helveticus 209, a strain chosen for its high proteolytic activity. To enhance the release of peptidic fractions, during fermentation pH was kept at 6 by using NaOH, Ca(CO)3 or Ca(OH)2. Cell-free supernatant was recovered by centrifugation, supplemented or not with maltodextrin and spray-dried. The profile of peptidic fractions released was studied by RP-HPLC. The lactose, Na and Ca content was also determined. The powder obtained was administered to BALB ⁄ c mice for 5 or 7 consecutive days, resulting in the proliferation of IgA-producing cells in the small intestine mucosa of the animals. Conclusions: Buttermilk is a suitable substrate for the fermentation with Lact. helveticus 209 and the release of peptide fractions able to be spray-dried and to modulate the gut mucosa in vivo. Significance and Impact of the Study: A powder enriched with peptides released from buttermilk proteins, with potential applications as a functional food additive, was obtained by spray-drying. A novel use of buttermilk as sub- strate for lactic fermentation is reported.

Signaling properties of a covalent modification cycle are altered by a downstream target Ventura, Alejandra; Jiang, Peng; Van Wassenhove, Lauren; Del Vecchio, Domitilla; Merajver, Sofia D.; Ninfa, Alexander J. We used a model system of purified components to explore the effects of a downstream target on the signaling properties of a covalent modification cycle, an example of retroactivity. In the experimental system used, a bifunctional enzyme catalyzed the modification and demodification of its substrate protein, with both activities regulated by a small molecule stimulus. Here we examined how a downstream target for one or both forms of the substrate of the covalent modification cycle affected the steady-state output of the system, the sensitivity of the response to the stimulus, and the concentration of the stimulus required to provide the half-maximal response (S50). When both the modified and unmodified forms of the substrate protein were sequestered by the downstream target, the sensitivity of the response was dramatically decreased, but the S50 was only modestly affected. Conversely, when the downstream target only sequestered the unmodified form of the substrate protein, significant effects were observed on both system sensitivity and S 50. Behaviors of the experimental systems were well approximated both by simple models allowing analytical solutions and by a detailed model based on the known interactions and enzymatic activities. Modeling and experimentation indicated that retroactivity may result in subsensitive responses, even if the covalent modification cycle displays significant ultrasensitivity in the absence of retroactivity. Thus, we provide examples of how a downstream target can alter the signaling properties of an upstream signal transduction covalent modification cycle.

Requirement for Ergosterol in V-ATPase Function Underlies Antifungal Activity of Azole Drugs Zhang, Yong-Qiang; Gamarra, Maria Soledad; Garcia, Guillermo Manuel; Park, Steven; Perlin, David S.; Rao, Rajini Ergosterol is an important constituent of fungal membranes. Azoles inhibit ergosterol biosynthesis, although the cellular basis for their antifungal activity is not understood. We used multiple approaches to demonstrate a critical requirement for ergosterol in vacuolar H+-ATPase function, which is known to be essential for fungal virulence. Ergosterol biosynthesis mutants of S. cerevisiae failed to acidify the vacuole and exhibited multiple vma~ phenotypes. Extraction of ergosterol from vacuolar membranes also inactivated V-ATPase without disrupting membrane association of its subdomains. In both S. cerevisiae and the fungal pathogen C. albicans, fluconazole impaired vacuolar acidification, whereas concomitant ergosterol feeding restored V-ATPase function and cell growth. Furthermore, fluconazole exacerbated cytosolic Ca2+ and H+ surges triggered by the antimicrobial agent amiodarone, and impaired Ca2+ sequestration in purified vacuolar vesicles. These findings provide a mechanistic basis for the synergy between azoles and amiodarone observed in vitro. Moreover, we show the clinical potential of this synergy in treatment of systemic fungal infections using a murine model of Candidiasis. In summary, we demonstrate a new regulatory component in fungal V-ATPase function, a novel role for ergosterol in vacuolar ion homeostasis, a plausible cellular mechanism for azole toxicity in fungi, and preliminary in vivo evidence for synergism between two antifungal agents. New insights into the cellular basis of azole toxicity in fungi may broaden therapeutic regimens for patient populations afflicted with systemic fungal infections.

Bioactive compounds and antioxidant capacity of fruit on Sechium edule Albarracin, Graciela; Lucero López, Viviana Romina; Marchevsky, Eduardo Jorge; Escudero, Nora Lilian Vegetables and fruits contain bioactive compounds with antioxidant activity such as phenols and flavonoids, carotenoids, ascorbate, alimentary fiber, selenium and many substances with antiatherogenics and anticarcinogenics properties. The purpose of this work is to assess some bioactive constituents and the antioxidant activity of the Sechium edule (Jacq) Swartz (Cucurbitaceae) fruit. Total phenol content was higher (p <0,001) in pulp (Sep):124.83mg/100g than seed (Ses): 86.36mg/100g. The antioxidant activity were estimated by: nitric oxide scavenging activity (NO), DPPH radicalscavenging activity (DPPH) and β-carotene bleaching method (β-carotene). The values expressed as percentage (%) corresponds to Ses and Sep respectively: NO 47.51 ± 1.9 and 55.62 ± 1.3; DPPH: 88.87 ± 1.1 and 89.13 ± 1.5 and β-carotene, 63.32 ± 1.5 and 53.15 ± 1.4. The studied samples have important radical scavenging activity and inhibited lipid peroxidation in vitro. We concluded that the present study provides infor- mation that Sechium edule can be a source of natural antioxidants.

Nuevas evidencias de la actividad sísmica del terreno Cuyania en la región de subducción de placa horizontal de Argentina; New evidence for the seismic activity of the Cuyania terrane in the flat slab subduction region of Argentina Alvarado, Patricia Monica; Sánchez, Gerardo; Saez, Mauro; Castro, Brigida Marta Ester El terreno Cuyania situado en la zona andina de trasarco entre 29°S y 34°S se compone de un sistema de corrimientos y retrocorrimientos del cinturón plegado de Precordillera y más hacia el este por bloques de basamento cristalino de las Sierras Pampeanas Occidentales. A 31°S aproximadamente, la zona se caracteriza por una elevada actividad sísmica que ocurre a niveles de corteza continental (< 35 km de profundidad) y de profundidad intermedia (~100 km). Esta última define la zona de Wadati-Benioff indicando una geometría de la placa de Nazca subducida en posición horizontal bajo Sudamérica en buena correlación con la localización de la dorsal de Juan Fernández, la cual parece continuar en subducción en dirección hacia el noreste bajo el continente. En este trabajo se presentan los resultados de la inversión del tensor momento sísmico para cinco sismos corticales que ocurrieron en 2008 y 2009 con epicentros en el terreno Cuyania y sus límites. La información obtenida corresponde a estimaciones refinadas de localización sísmica, momento sísmico (M0), magnitud momento (Mw), profundidad focal y parámetros de fallamiento para los mecanismos focales de estos sismos. La caracterización de estas fuentes sísmicas ha sido obtenida a partir del modelizado de formas de ondas sísmicas de bancha ancha completas para las tres componentes registradas por la red local SIerras pampeanas Experiment using a Multicomponent BRoadband Array (SIEMBRA). Los sismos estudiados muestran magnitudes Mw entre 3.5 y 5.3, mecanismos focales de fallamiento inverso y profundidades focales entre 5 y 30 km, lo cual es consistente con otras soluciones obtenidas anteriormente para la misma zona con técnicas similares. Esta deformación sísmica está de acuerdo con el régimen de esfuerzo compresivo actual observado dentro de la corteza del terreno Cuyania situada por encima de la placa de Nazca subducida horizontalmente. Las propiedades de la corteza del terreno Cuyania (espesor de ~50 km; alta velocidad de ondas P, alta relación entre las velocidades de ondas P y S y elevada densidad en sus niveles más profundos), del manto superior situado entre la zona de Wadati-Benioff y el Moho y un mayor acoplamiento entre las litósferas continental y oceánica favorecerían la transferencia de esfuerzos desde la zona de contacto de placas a más de 500 km hacia el este, causando una mayor generación de sismos corticales en el terreno Cuyania que en los terrenos adyacentes.; The Cuyania terrane in the Andean backarc region between 29°S and 34°S consists of the thin–skinned Precordillera fold and thrust belt and of the Western Sierras Pampeanas thick–skinned basement cored uplifts. At about 31°S, the region is highly seismically active at crustal levels (< 35 km depth) and intermediate depths (~100 km). This deeper seismic activity delimitates the Wadati–Benioff zone showing a geometry of the subducted Nazca plate nearly horizontal beneath South America in good correlation with the location of the Juan Fernandez ridge, which seems to continue its subduction to the northeast beneath the continental plate. In this paper we present the results of the seismic moment tensor inversion forfive crustal earthquakes that occurred in 2008 and 2009 with epicenters in the Cuyania terrane and its boundaries. We provide refined information of the seismic location, seismic moment (M0), moment magnitude (Mw), focal depth and fault parameters of the focal mechanisms for these earthquakes. The seismic source characterization was obtained after modeling the three component full seismic broadband waveforms recorded by the Sierras Pampeanas Experiment using a Multicomponent BRoadband Array (SIEMBRA) local network. The earthquakes show magnitudes Mw between 3.5 and 5.3, dip–slip focal mechanisms and focal depths between 5 and 30 km, which are consistent with previous constraints in the same area using similar inversion techniques. The earthquake deformation is expected according to the compressional stress regime estimated in the crust of the Cuyania terrane over the flat slab subduction segment. The properties of the Cuyania terrane (thick crust of about 50 km thickness; high P–wave velocity; high P– to S–wave velocity ratio and high density in its deeper levels), of the upper mantle between the Wadati–Benioff zone and the Moho, and a stronger coupling between the oceanic and continental lithospheres may favor the transference of stresses from the coupled zone in the west to more extended inland areas located 500 km to the east causing a higher generation of crustal earthquakes in the Cuyania terrane in comparison to adjacent crustal terranes.

Likelihood-Based Sufficient Dimension Reduction. Letters to the Editor Forzani, Liliana Maria Discussion of the paper Likelihood based sufficient dimension reduction

On packing and covering polyhedra of consecutive ones circulant clutters Aguilera, Néstor Edgardo Building on work by G. Cornuéjols and B. Novick and by L. Trotter, we give different characterizations of contractions of consecutive ones circulant clutters that give back consecutive ones circulant clutters. Based on a recent result by G. Argiroffo and S. Bianchi, we then arrive at characterizations of the vertices of the fractional set covering polyhedron of these clutters. We obtain similar characterizations for the fractional set packing polyhedron using a result by F.B. Shepherd, and relate our findings with similar ones obtained by A. Wagler for the clique relaxation of the stable set polytope of webs. Finally, we show how our results can be used to obtain some old and new results on the corresponding fractional set covering polyhedron using properties of Farey series. Our results do not depend on Lehman's work or blocker/antiblocker duality, as is traditional in the field.

South American atmospheric circulation anomalies related to droughts in the northwest of Argentina (1951-1980) Bobba, M. E.; Minetti, Juan Leonidas Con base en un índice de sequía regional realizado por otros autores (Minetti et al., 2004), ha sido posible asociar sequías con anomalías de presión atmosférica en América del Sur. Se ha tratado de agrupar los campos de anomalías de presión atmosférica, que muestran cambios de circulación, con los índices de sequía. Se aplicó la metodología de Lund a escala mensual, estacional y anual, lo que permitió seleccionar un pequeño número de sequías fuertes relacionadas con la circulación. Como resultado hemos concluido que algunas de estas sequías fuertes están asociadas con los factores que se mencionan a continuación. Las principales alteraciones de circulación relacionadas con sequías describen en la mayoría de los casos lo siguiente: a) gradientes transcordilleranos significativos, en este caso incluimos aquellas que intensifican los vientos zonales del oeste (oeste–este) sobre Patagonia, lo cual genera anticiclogénesis sobre la costa oceánica pacífica y ciclogénesis en el continente; b) subsidencia anticiclónica; c) debilitamiento de la corriente húmeda del norte debido a una disminución del gradiente entre el anticiclón del océano Atlántico y la depresión continental y/ o subsidencia continental asociada con la corriente proveniente de esta dirección.; Based on a regional drought index carried out by other authors (Minetti et al., 2004), it has been possible to associate droughts with atmospheric pressure anomalies in South America. We attempted to group the fields of atmospheric pressure anomalies, which show circulation changes, with these drought indexes. We applied Lund's methodology based on a monthly, seasonal and annual scale. It has been possible to select a small number of severe droughts related to circulation. Consequently, we conclude that some severe droughts are associated with the factors listed below. The main circulation alterations related to droughts describe in most cases the following: a) significant mountain range gradients, in this case we include the one that intensifies the western zonal flow (west–east) over Patagonia, which generates an anticyclogenesis on the Pacific Ocean coast and a cyclogenesis on the continent, b) anticyclonic subsidence, c) weakness of the north humid flow due to a diminution of the gradient between the Atlantic Ocean anticyclone and the continental depression and/or subsidence associated with the flow coming from this direction.

TracED: A tool for capturing and tracing engineering design processes Roldán, María Luciana; Gonnet, Silvio Miguel; Leone, Horacio Pascual The design of products or production processes in many engineering disciplines such as chemical, or software engineering, involves many creative and sometimes unstructured activities, with an opportunistic control flow. During these design processes, several models are generated, which have different levels of abstraction of the object being designed. Given the difficulties in dealing with this complexity using an improvised way, there is an urgent need for tools that support the capture and tracing of this process. In this proposal, TracED, a computational environment to support the capture and tracing of engineering design process is presented. It allows defining a particular engineering design domain and supporting the capture of how products under development are transformed along an engineering design process. Particularly, in this work, we consider software architectures design domain. As in any complex process, the support of computational tools is required for enabling its capture.

Catalytic stereoselective alkene aziridination with sulfonimidamides Robert-Peillard, Fabien; Di Chenna, Pablo Hector; Liang, Chungen; Lescot, Camille; Collet, Florence; Dodd, Robert H.; Dauban, Philippe Diastereoselective copper-catalyzed alkene aziridination has been investigated using chiral nitrenes generated from sulfonimidamides in the presence of an iodine(III) oxidant. Starting from a stoichiometric amount of the substrates, the corresponding aziridines were isolated with excellent yields of up to 96%. Good levels of asymmetric induction were obtained in the case of electron-poor olefins, with an optimal de of 94% being reached starting from tert-butyl acrylate. Matching and mismatching effects were also observed upon the use of chiral copper catalysts for the aziridination of styrene.