O2 and O3 regeneration of PtReSn/Al2O 3 and PtReGe/Al2O3 naphtha reforming catalysts prepared by catalytic reduction D'Ippolito, Silvana A.; Especel, Catherine; Epron, Florence; Marécot, Patrice; Pieck, Carlos Luis The deactivation and regeneration of naphtha reforming PtReGe/Al 2O3 and PtReSn/Al2O3 catalysts prepared by catalytic reduction were studied. The extent and nature of coke deposition as determined by TPO were related to catalyst properties such as dispersion, acidity and Cl content. The PtReSn catalyst was the most resistant to coke deactivation. Regeneration was performed by calcination in oxygen at 450 °C or ozone at 125 °C at variable regeneration times. Regenerated catalysts were evaluated by cyclopentane hydrogenolysis, cyclohexane dehydrogenation and n-heptane reaction tests. Regeneration by oxygen burning-off was the most effective for decoking. However, oxygen combustion produced more segregation of the metal function than ozone regeneration. With the regeneration conditions used in this work, the original acidity of the catalysts cannot be recovered.

Isobutane Alkylation with Solid Catalysts based on Beta-Zeolite Dalla Costa, Bruno Oscar; Querini, Carlos Alberto The isobutane alkylation with butenes is a reaction in which the substitution of mineral acids, such as sulphuric and hydrofluoric acids, by solid acid catalysts is highly desirable. Solid catalysts with good activity and selectivity for this reaction have been previously reported. However, bad stability is a major drawback in most cases. In this work, catalysts based on beta zeolite, exchanged with lanthanum were studied. It was found that these catalysts have lower activity than the Y zeolite both, in the protonic form, or with lanthanum in replacement of protons. EDX analyses showed that lanthanum is practically fully removed from the zeolite structure during an exchange with ammonium nitrate, even though the catalyst was precalcined. The total acidity as measured by pyridine temperature-programmed desorption is similar in the beta and the Y zeolites. However, the former zeolite has stronger acid sites, and because of this, the deactivation process occurs faster. Pulses of 1-butene at different temperatures can be used as a technique to predict the catalytic behavior of acid catalysts in the alkylation reaction. Using this technique, it was possible to determine that the beta zeolite is deactivated during the alkylation reaction by pore mouth plugging. The addition of platinum to the beta zeolite is useful in order to regenerate the catalyst using hydrogen at 80 °C, although long times are needed to accomplish this regeneration. © 2010 Elsevier B.V.

α-Melanocyte-stimulating hormone (α-MSH) reverses impairment of memory reconsolidation induced by interleukin-1 beta (IL-1 beta) hippocampal infusions Machado, Ivana Noelia; Gonzalez, Patricia Verónica; Schiöth, Helgi Birgir; Lasaga, Mercedes Isabel; Scimonelli, Teresa Nieves Interleukin-1 beta (IL-1β) significantly influences cognitive processes. Treatments which raise the level of IL-1β in the brain impair memory consolidation in contextual fear conditioning. However, the effect of IL-1β on memory reconsolidation has not yet been established. The melanocortin α-melanocyte-stimulating hormone (α-MSH) exerts potent anti-inflammatory actions by antagonizing the effect of proinflammatory cytokines. Five subtypes of melanocortin receptors (MC1R–MC5R) have been identified, of which MC3R and MC4R are predominant in the central nervous system. The present experiments show that the injection of IL-1β (5 ng/0.25 μl) in dorsal hippocampus up to 30 min after re-exposition to the context decreases freezing during the contextual fear test. Impairment of memory reconsolidation was reversed by treatment with α-MSH (0.05 μg/0.25 μl). Administration of the MC4 receptor antagonist HS014 (0.5 μg/0.25 μl) blocked the effect of α-MSH. These results suggest that IL-1β may influence memory reconsolidation and that activation of central MC4R could lead to improve cognitive performance.

Reflexiones sobre la capacitación de profesores: la construcción de modelos y la práctica experimental como promotores de la discusión; Thinking about teachers training: model construction and experimental activities like discussion promoters Idoyaga, Ignacio Julio; Torti, Horacio; Barrado, Andrés; Spena, Diego; Lorenzo, Maria Gabriela El objetivo de este trabajo es presentar el estudio descriptivo sobre experiencias con modalidad de taller en donde se introduce el diseño de modelos como contenido conceptual, procedimental y actitudinal, central en la enseñanza de las ciencias en un marco constructivista. La construcción de conocimientos en alumnos universitarios y de nivel medio (al menos) puede articularse, del mismo modo en que avanza la ciencia, proponiendo modelos para explicar la experiencia. Dentro de las actividades encaradas por el Centro de Investigación y Apoyo a la Educación Científica (CIAEC), el grupo dicta periódicamente un taller destinado a la actualización de profesores de todos los niveles. El análisis del material producido por los capacitandos y las observaciones de los capacitadores muestran como principales logros la reflexión sobre el proceso de construcción de conocimiento; la incorporación del concepto de modelo; y la práctica en las tareas medición y comunicación de resultados.; The aim of this work is to describe the experiences in a workshop that presents modeling design as conceptual, procedimental and attitudinal contents. Modeling design is positioned in science teaching in a constructivist environment. The construction of knowledge in college and school pupils can be articulated in the same way that science improves, proposing models to explain the experiences. As one of the activities developed by the Research Center and Support to Scientific Education (CIAEC), the group periodically gives an actualization workshop for professors of all levels. The observation and the analysis of the work production of the assistants shows that manuality in the use of laboratory instruments, correct communication of results and reflection about how knowledge is constructed are the principal achieves of the workshop.

Clinical features of facioscapulohumeral muscular dystrophy 2 De Greef, J. C.; Lemmers, R. J. L. F.; Camaño, P.; Day, J. W.; Sacconi, S.; Dunand, M.; Van Engelen, B. G. M.; Kiuru Enari, S.; Padberg, G. W.; Rosa, Alberto Luis; Desnuelle, C.; Spuler, S.; Tarnopolsky, M.; Venance, S. L.; Frants, R. R.; Van Der Maarel, S. M.; Tawil, R. Objective: In some 5% of patients with facioscapulohumeral muscular dystrophy (FSHD), no D4Z4 repeat contraction on chromosome 4q35 is observed. Such patients, termed patients with FSHD2, show loss of DNA methylation and heterochromatin markers at the D4Z4 repeat that are similar to patients with D4Z4 contractions (FSHD1). This commonality suggests that a change in D4Z4 chromatin structure unifies FSHD1 and FSHD2. The aim of our study was to critically evaluate the clinical features in patients with FSHD2 in order to establish whether these patients are phenotypically identical to FSHD1 and to establish the effects of the (epi-) genotype on the phenotype. Methods: This cross-sectional study studied 33 patients with FSHD2 from 27 families, the largest cohort described to date. All patients were clinically assessed using a standardized clinical evaluation form. Genotype analysis was performed by pulsed field gel electrophoresis and PCR; D4Z4 methylation was studied by methylation-sensitive Southern blot analysis. Results: FSHD2 is identical to FSHD1 in its clinical presentation. Notable differences include a higher incidence (67%) of sporadic cases and the absence of gender differences in disease severity in FSHD2. Overall, average disease severity in FSHD2 was similar to that reported in FSHD1 and was not influenced by D4Z4 repeat size. In FSHD2, a small effect of the degree of hypomethylation on disease severity was observed. Conclusions: Clinically, patients with FSHD2 are indistinguishable from patients with FSHD1. The present data suggest that FSHD1 and FSHD2 are the result of the same pathophysiologic process. METHODS: This cross-sectional study studied 33 patients with FSHD2 from 27 families, the largest cohort described to date. All patients were clinically assessed using a standardized clinical evaluation form. Genotype analysis was performed by pulsed field gel electrophoresis and PCR; D4Z4 methylation was studied by methylation-sensitive Southern blot analysis. RESULTS: FSHD2 is identical to FSHD1 in its clinical presentation. Notable differences include a higher incidence (67%) of sporadic cases and the absence of gender differences in disease severity in FSHD2. Overall, average disease severity in FSHD2 was similar to that reported in FSHD1 and was not influenced by D4Z4 repeat size. In FSHD2, a small effect of the degree of hypomethylation on disease severity was observed. CONCLUSIONS: Clinically, patients with FSHD2 are indistinguishable from patients with FSHD1. The present data suggest that FSHD1 and FSHD2 are the result of the same pathophysiologic process.

Crystallographic and spectroscopic characterization of LnFeTeO6 (Ln = La, Pr, Nd, Sm) materials Lavat, Araceli Elisabet; Mercader, Roberto Carlos; Baran, Enrique José Four mixed oxides of composition LnFeTeO6 (with Ln = La, Pr, Nd, Sm), belonging to a superstructure of the PbSb2O6 structural type, have been prepared by solid state reactions and their unit cell parameters determined by X-ray powder diffractometry. The infrared and Raman spectra of these materials were also recorded and briefly discussed, on the basis of a site-symmetry analysis. The 57Fe-Mössbauer spectra show that the FeIIIO6 octahedra present in these materials are not greatly distorted.

Digital Implementation of Method for Discontinuous Current Mode Compensation Of High-Performance Line-Commutated Converters Maestri, Sebastian Oscar; Benedetti, Mario; Uicich, Gustavo Cesar; Gomez Costa, Jose Luis; Petrocelli, Roberto Many high-performance power converters at CERN are implemented with thyristors, mostly in CCM (Continuous Conduction Mode) due to their better dynamic response. In DCM (Discontinuous Conduction Mode), the converter reduces its small-signal gain, producing a degraded time response which can lead to instability. Several of these converters use digital regulation, allowing the implementation of complex nonlinear control techniques. Therefore, a strategy to control the converters in DCM (Discontinuous Conduction Mode) can be implemented, bearing in mind that their standard operation (sampling time, measured signals, acquisition system) can not be drastically changed. This report presents the implementation of a new method to control line-commutated converters in discontinuous conduction mode (DCM). The method is based on the modi cation of the thyristor's ring angle α using a linear approximation, yielding nearly the same dynamic performance as in continuous conduction mode. The ring angle is corrected by adding a supplementary angle ∆α, calculated by estimating the average output current. The proposed technique signi cantly reduces computational burden, being suitable for on-line calculation. Both, simulations and experimental results are presented on a 1kW laboratory prototype based on CERN GEREG crate.

Research priorities for neglected infectious diseases in Latin America and the Caribbean region Dujardin, Jean Claude; Herrera, Socrates; Rosario, Virgilio do; Arevalo, Jorge; Boelaert, Marleen; Carrasco, Hernán J.; Correa Oliveira, Rodrigo; García, Lineth; Gotuzzo, Eduardo; Gyorkos, Theresa W.; Kalergis, Alexis M.; Kouri, Gustavo; Larraga, Vicente; Lutumba, Pascal; Macías García, Maria Angeles; Manrique Saide, Pablo C.; Modabber, Farrokh; Nieto, Alberto; Pluschke, Gerd; Robello, Carlos; Rojas de Arias, Antonieta; Rumbo, Martín; Santos Preciado, Jose Ignacio; Sundar, Shyam; Torres, Jaime; Torrico, Faustino; Van der Stuyft, Patrick; Victoir, Kathleen; Olesen, Ole F. Neglected infectious diseases (NIDs) constitute a group of tropical infections which thrive among impoverished populations of developing countries, mainly tropical, in remote rural areas, urban slums and conflict zones (WHO & Carter Center 2008).  They include a range of chronic disabling or more acute infections due to protozoa, helminths, bacteria, viruses or fungi. Globally, NIDs cause an estimated 500,000 deaths each year and inflict severe physical disabilities, jeopardizing child growth and pregnancy outcomes. The aggregate disability-adjusted life year (DALY) tally for NIDs is 56.6 million, which exceeds the tally of malaria (46 million DALY) or tuberculosis (TB) (35 million DALY) (Hotez et al. 2007). By reducing economic productivity, NIDs hinder socioeconomic development in endemic countries and affect the quality of life at all levels. The concept of ‘neglect’ was evoked to signal both market and public sector failure in R&D for drug developement: on the one hand, NIDs affect a large number of people who are unable to pay for access to healthcare, and thus represent an uninteresting market for pharmaceutical companies, on the other hand, NIDs did not (for long) constitute a priority for governments and for funding agencies (Torreele et al 2004. A needs-based pharmaceutical R&D agenda for neglected diseases). When world leaders adopted the Millennium Declaration in September 2000, the fight against "HIV/AIDS, malaria and other diseases" was included as the sixth goal. This resulted in significant global support to combat the three major poverty-related diseases (HIV/AIDS, malaria and TB), whereas NIDs remained largely forgotten. This situation is currently changing, and the international community is increasingly becoming aware of the importance of confronting NIDs. The increased focus on NIDs runs along two tracks of activities. The first is focused on short term improvement of public health by control and elimination of NIDs using currently available tools and methodologies. The second line of activities is research into NIDs in order to develop new or improved products and methodologies for long-term disease control and elimination. Since then, the World Health Assembly (WHA) has established a working group on "needs-driven, essential health R&D", while the OECD countries have given political support to NID research in the Noordwijk agenda in June 2007. In the US, the National Institute of Allergy and Infectious Diseases (NIAID) has intensified its long-standing programme of research in NIDs, while several private charities such as the Bill and Melinda Gates Foundation have also increased their support to NID research.

Batrachochytrium dendrobatidis in Argentina: First record of infection in Hypsiboas cordobae and Odontophrynus occidentalis tadpoles, in San Luis province, Argentina Gutierrez, Flavia R.; Arellano, María Luz; Moreno, Liliana Elizabeth; Natale, Guillermo Sebastian On October 12th 2009, ten live larvae of Hypsiboas cordobae and Odontophrynus occidentalis were collected randomly in a pond during a field survey in the Strict Natural Reserve “Quebarada de las Higueritas” , San Luis province.The individuals were fixed in the field in 10% neutral buffered formaldehyde and then transferred to ethanol 70%. All oral structures of tadpoles were examined visually in the laboratory under a stereoscopic microscope. Samples of the queratinazed mouthparts were taken, which were dehydrated, paraffin-embedded and cut into five micron–thick sections for histological analysis. We identified anomalies in the keratinized mouthparts 5 of 10 individuals analyzed. The anomalies included mainly lack of pigmentation in upper and lower jaw sheaths, erosion of their cutting edge and absence of serrations, and some time lost of some labial teeth (Fig. 2). For histological analysis 7 of the 10 larvae analyzed were positive to Bd presence. Spherical and ovoid zoosporangia, empty or containing zoospores, were identified in the keratinized mouthparts. The sporangia ranged between 5 and 12 µm in diameter.

Aportes preliminares para la construcción de las secuencias de producción cerámica en la aldea agroalfarera Piedra Negra (I milenio d.C.), Laguna Blanca, Belén, Catamarca Espiro, Valeria Elizabeth Este artículo, representa el primer acercamiento a las secuencias de procesos de manufactura identificadas en los materiales cerámicos provenientes de la Aldea Agroalfarera Piedra Negra, ubicada en el distrito Laguna Blanca, Belén, Catamarca. Para la realización de nuestro análisis partimos de observaciones macroscópicas, submacroscópica y microscópicas de los materiales cerámicos de una base residencial de la Aldea, logrando la reconstrucción de las secuencias de procesos técnicos empleados. La identificación y descripción de estas secuencias de procesos se constituye en un paso previo indispensable para la determinación de una tradición alfarera local en Laguna Blanca.; This article represents a first approach to the manufacturing process sequences identified in ceramics from the Piedra Negra Village, located in Laguna Blanca district, Belen, Catamarca. To carry out our analysis we start from macroscopic, sub-macroscopic and microscopic observations of the ceramic materials from a household of the Village, making the reconstruction of the sequences of technical processing staff. The identification and description of these sequences of processes constitutes an indispensable step for the determination of a local pottery tradition in Laguna Blanca.

Effects of T-type calcium channel blockers on cocaine-induced hyperlocomotion and thalamocortical GABAergic abnormalities in mice Bisagno, Veronica; Raineri Andersen, Mariana; Peskin, Viviana Andrea; Wikinski, Silvia Ines; Uchitel, Osvaldo Daniel; Llinás, Rodolfo R.; Urbano Suarez, Francisco Jose Rationale: Repetitive cocaine exposure has been shown to induce GABAergic thalamic alterations. Given the key role of T-type (CaV3) calcium channels in thalamocortical physiology, the direct involvement of these calcium channels in cocaine-mediated effects needs to be further explored. Objective: The objective of this study was to investigate the effect of T-type calcium channel blockers on acute and repetitive cocaine administration that mediates thalamocortical alterations in mice using three different T-type blockers: 2-octanol, nickel, and mibefradil. Methods: During in vitro experiments, whole-cell patch-clamp recordings were conducted in ventrobasal (VB) thalamic neurons from mice treated with acute repetitive cocaine administration (3∈×∈15 mg/kg, i.p., 1 h apart), under bath application of mibefradil (10 μM), 2-octanol (50 μM), or nickel (200 μM). After systemic administration of T-type calcium channel blockers, we evaluated locomotor activity and also recorded GABAergic neurotransmission onto VB neurons in vitro. Results: Bath-applied mibefradil, 2-octanol, or nickel significantly reduced both GABAergic neurotransmission and T-type currents of VB neurons in cocaine-treated mice. In vivo i.p. pre-administration of either mibefradil (20 mg/kg and 5 mg/kg) or 2-octanol (0.5 mg/kg and 0.07 mg/kg) significantly reduced GABAergic mini frequencies onto VB neurons. Moreover, both mibefradil and 2-octanol were able to decrease cocaine-induced hyperlocomotion. Conclusion: The results shown in this study strongly suggest that T-type calcium channels play a key role in cocaine-mediated GABAergic thalamocortical alterations, and further propose T-type channel blockers as potential targets for future pharmacological strategies aimed at treating cocaine's deleterious effects on physiology and behavior.

La implicancia de la memoria y la identidad en la constitución del patrimonio. Algunas reflexiones Colasurdo, María Belén; Sartori, Julieta Isabel; Escudero, Sandra Cristina En el presente trabajo se reflexiona acerca de la relación entre los conceptos de MEMORIA – IDENTIDAD – PATRIMONIO desde un enfoque antropológico. A partir de la ambigüedad intrínseca que caracteriza a los mismos, se considera el papel preponderante que juegan los mecanismos de memoria/olvido-identidades individuales/identidad colectiva en la elección de lo que será considerado patrimonio dentro de una comunidad. El concepto de patrimonio no ha sido el mismo a lo largo de la historia y su cambiante significado ha transitado, desde la idea inicial de tesoro ilustrado, hasta la de recurso turístico, pasando por su valoración como producto cultural y mecanismo de construcción de identidad. El museo es una de las instituciones que se encargan de determinar y perpetuar qué se considera patrimonio y qué no. El mismo puede representar bien o mal el pasado, puede distorsionarlo a partir de sus selecciones y clasificaciones, puede restringir el pasado a través de su código de representación histórica, la forma en que cuenta su historia, la forma en que son presentados los artefactos. Estos últimos son reunidos y presentados para generar un sentido particular para el visitante que los observa.; This paper is about the relation between the concepts of MEMORY – IDENTITY – PATRIMONY from an anthropological focus. Since the intrinsic ambiguity of those concepts, it´s considered the preponderant role play by the mechanism of memory/oblivion-identities individualities/collective identity in the choose of what it will be considered patrimony inside a community. The concept of patrimony have not been the same along the history and it´s changing meaning have evolve since the idea of an illustrated treasure to the idea of a touristic resource, and rating it as a cultural product and a mechanism of identity construction. The museum is one of the institution in charge of determine and perpetuate what is consider patrimony and what is not. This could represent the past, in a reliable way or not, it could distort it from its selections and classifications, it could restrict the past because of its codes of historic representation, the way in which it tell it story, the way in which the artifacts are presented. The artifacts are gathered and presented to generate a particular sense to the visitor that observes it.

The Russian and Argentinian experiences of radical reform: between economy and politics Heredia, Mariana Laura; Kirtchik, Olessia The 1970s and 80s saw a wave of market liberalization in Latin America, Africa, and Asia, but also in the United States and Western Europe, reaching Central and Eastern Europe by the end of the 1980s. Existing studies tend to focus on the decision-makers and adopt a monolithic view of reform implementation. To account for complexity, we study the cases of Argentina and the USSR/Russia from tentative market liberalization in the 1970s until the crisis of neoliberalism in the late 20th and early 21st century. After brief observations on the history of economic reform in each country, we consider the preconditions of reforms and the delegation of decision-making to economists; the institutional context and, in particular, tensions between political democratization and economic liberalization; and the unequal influence of neoliberal ideas within Russian and Argentinean institutions. Finally, we assess whether the neoliberal order remained intact after the crises of 1998 and 2001. In English, extensive summary in Russian.

Comparing post-soviet and Latin American societies: from “transition” to “transformation" Heredia, Mariana Laura; Kazakova, Olessia Introduction to a thematic issue entitled “Russia/former USSR/Latin America: Studies in Post-Authoritarian Transformation.” Because of language barriers and a lack of institutionalized ties, the impressive literature on democratization in each of these areas is virtually unknown to authors from the other region. The striking similarities between the former Soviet Union and Latin America are best studied through comparison based on ground-level fieldwork. This approach highlights the blind spots of standard democratization and free-market modernization theory, which tends to universalize scenarios of economic development without paying sufficient attention to case studies. The introduction outlines the conceptual shift from “transition” to “transformation” in the literature on democratization, and presents the articles in the issue as well as some of the challenges the editors faced in bringing authors from Latin America and the former USSR together. English and Russian versions.

La sinergia en la producción de la información ambiental Coria, Lorena Gabriela La cuestión ambiental enfrenta desafíos que ponen en juego un conjunto de actores que participan directa o indirectamente en el marco de la configuración de las situaciones ambientales con distinto grado de riesgo y manifestación en las escalas territoriales. Encontramos así, actores que por acción u omisión generan consecuencias ambientales y otros que las sufren. Por otro lado, desde el plano de la producción del conocimiento, continúa el debate sobre las implicancias terminológicas vinculadas a algunos conceptos claves sobre los cuales se estructuran la cuestión ambiental.

Populismo, regeneracionismo y democracia Aboy Carles, Gerardo Este trabajo desarrolla un diálogo crítico con la interpretación de Ernesto Laclau sobre la teoría de la hegemonía y su conceptualización del populismo. En primer lugar, se demuestra como la impureza que caracteriza a las lógicas de la hegemonía nos llevan a concebir a las identidades políticas como solidaridades híbridas, de fronteras superpuestas, alejadas de la imagen laclausiana de formaciones excluyentes. Los populismos clásicos latinoamericanos han constituido un mecanismo particular, entre otros posibles, de resolver las tensiones entre la representación de una parte y la representación de la comunidad en su conjunto. La identificación entre política y populismo realizada por Laclau resulta entonces problemática. En consecuencia, el populismo no puede ser reducido a una dicotomización antagónica de la comunidad, y, la regeneración de los actores pasará a ocupar un lugar central en la caracterización del fenómeno.; This work develops a critical dialog with Ernesto Laclau's theory of hegemony and his conceptualization of populism. Firstly, it argues that the impurity that characterizes the logics of hegemony leads us to conceiving political identities as hybrid solidarities, of superposed borders. This is a different image from Laclau's exclusive identities. Classic Latin-American populisms have constituted a particular mechanism, among others, of solving the tensions between the representation of a part and the representation of the whole community. Laclau's identification between politics and populism becomes problematic. Consequently, populism cannot be reduced to an antagonistic dichotomization of the community. The regeneration of the actors involved in a populist practice will thus occupy a central place in the characterization of this political phenomenon.

Effect of post-weld heat treatment on the wear resistance of hardfacing martensitic steel deposits Gualco, Agustín; Svoboda, Hernán Gabriel; Surian, Estela Silvia; de Vedia, Luis Alberto The effect of different post-weld heat treatments on the microstructure and wear resistance of martensitic deposits were studied. The deposit was welded using a metal-cored tubular wire, in the flat welding position, on a 375 × 75 × 19mm SAE 1010 plate, using 98% Ar-2% CO2 shielding gas mixture and with an average heat input of 2.8 kJ/mm. The samples were heat treated at temperatures between 500 and 6808C for 2 h. Chemical composition, Vicker's microhardness and wear properties with AMSLER tests in a sliding condition were determined. In the as welded condition, the microstructure was principally composed of martensite and retained austenite. Significant variations in wear resistance and hardness were measured for different tempering temperatures. For the different heat-treated conditions, it was observed that the decomposition of retained austenite to martensite and carbide precipitation was associated with the tempering of martensite. A secondary hardness effect was detected with maximum hardness of 710HV for 550°C heat treatment temperature. The best performance in wear test was obtained for this condition. Wear rates for the different conditions were obtained and mathematical expressions were developed. For each case, wear mechanisms were analyzed.

Control de Robots Móviles con Incertidumbres Dinámicas usando Redes de Base Radial Rossomando, Francisco Guido; Soria, Carlos Miguel; Carelli Albarracin, Ricardo Oscar En este trabajo se presenta un control de seguimiento de trayectorias de robots móviles. La estructura de control propuesta combina un modelo de linealización por realimentación basado en el modelo cinemático nominal, y una red neuronal directa para el control dinámico adaptable. La dinámica del robot es aprendida por una red neuronal basadas en funciones de base radial (RN-FBR) en un circuito de realimentación adaptable, ajustando el peso y las funciones de base radial. Se muestra un análisis de estabilidad del sistema de neuro-control adaptable. Se comprueba que los errores de control están limitados en función de la aproximación de error de la RN-FBR, la cual se comprueba con resultados experimentales.

Estudio observacional naturalistico sobre la efectividad del tratamiento farmacológico en una cohorte de pacientes con demencia tipo Alzheimer; Naturalist observational study on effectiveness of drug treatment of a cohort of patients with Alzheimer type dementia Rojas, Galeno; Bartoloni, Leonardo Carlos; Serrano, Cecilia Mariela; Dillon, Carol; Allegri, Ricardo Francisco Introduction: Naturalistic studies in clinical practice present great utility to guide the decision making and allow to corroborate the experimental findings of clinical trials. In Argentine, there are not published data of this type of studies in Alzheimer's Disease (DTA) with cholinesterase inhibitors. Objective: To evaluate effectiveness of treatment with donepezil patients with DTA mild degree in clinical practice. Materials and methods: Observational study, not controlled and longitudinal of 24 weeks of follow up in the Laboratory of Memory of the Zubizarreta Hospital. Were selected patients treated with donepezil with diagnosis of probable or possible mild DTA according to DSM IV and NINCDS-ADRDA criteria. The global, cognitive and behavioural domains were evaluated and Caregiver Burden. Results: Were selected for the analysis 38 patients whose completed the follow up, They were 63,15% (n=24) probable DTA and 36,84% (n=14) DTA with vascular component. At the end of the follow up a significant change in memory, visuespacial skills and language was demonstrated. Significance in global, behavioural and Caregiver Burden was not demonstrated nor activities of daily life. A 10% presented improvement of 2 points in MMSE (50% stayed stable, 39% deteriorated) to the 6 months. The parkinsonism risk was duplicated at the end of the study. Conclusion: In this work, a smaller group of patients with mild DTA responded favorably to donepezil in cognitive domain.Half of the patients stayed stable in their MMSE.

Integrable systems and Poisson-Lie T-duality: A finite dimensional example Capriotti, Santiago; Montani, Hugo Santos We study the deep connection between integrable models and Poisson-Lie T-duality working on a finite dimensional example constructed on SL(2,C) and its Iwasawa factors SU(2) and B. We shown the way in which the Adler-Kostant-Symes theory and collective dynamics combine to solve the equivalent systems by solving the factorization problem of an exponential curve in SL(2,C). It is shown that the Toda system embraces the dynamics of the systems on SU(2) and B.