The interplay between local immune response and Epstein–Barr virus-infected tonsillar cells could lead to viral infection control Vistarop, Aldana Georgina; Cohen, Melina; Huaman, Fuad; Irazu, Lucia; Rodriguez, Marcelo; de Matteo, Elena Noemí; Preciado, Maria Victoria; Chabay, Paola Andrea Epstein Barr virus (EBV) gains access to the host through tonsillar crypts. Our aim was to characterize microenvironment composition around EBV+ cells in tonsils from pediatric carriers, to disclose its role on viral pathogenesis. LMP1 expression, assessed by immunohistochemistry (IHC), was used to discriminate EBV + and – zones in 41 tonsil biopsies. Three regions were defined: Subepithelial (SE), interfollicular (IF) and germinal center (GC). CD8, GrB, CD68, IL10, Foxp3, PD1, CD56 and CD4 markers were evaluated by IHC; positive cells/100 total cells were counted. CD8+, GrB+, CD68+ and IL10+ cells were prevalent in EBV+ zones at the SE region (p < 0.0001, p = 0.03, p = 0.002 and p = 0.002 respectively, Wilcoxon test). CD4+ and CD68+ cell count were higher in EBV + GC (p = 0.01 and p = 0.0002 respectively, Wilcoxon test). Increment of CD8, GrB and CD68 at the SE region could indicate a specific response that may be due to local homing at viral entry, which could be counterbalanced by IL10, an immunosuppressive cytokine. Additionally, it could be hypothesized that CD4 augment at the GC may be involved in the EBV-induced B-cell growth control at this region, in which macrophages could also participate.

Catching Galactic open clusters in advanced stages of dynamical evolution Angelo, M.S.; Piatti, Andres Eduardo; Dias, W. S.; Maia, F. F. S. During their dynamical evolution, Galactic open clusters (OCs) gradually lose their stellar content mainly because of internal relaxation and tidal forces. In this context, the study of dynamically evolved OCs is necessary to properly understand such processes. We present a comprehensive Washington CT1 photometric analysis of six sparse OCs, namely ESO 518-3, Ruprecht 121, ESO 134-12, NGC6573, ESO 260-7, and ESO 065-7. We employed Markov chainMonte Carlo simulations to robustly determine the central coordinates and the structural parameters and T1 × (C - T1) colour-magnitude diagrams cleaned from field contamination were used to derive the fundamental parameters. ESO 518-03, Ruprecht 121, ESO 134-12, and NGC6573 resulted to be of nearly the same young age [8.2≤log(t yr-1) ≤8.3]; ESO 260-7 and ESO065-7 are of intermediate age [9.2≤log(t yr-1) ≤9.4]. All studied OCs are located at similar Galactocentric distances (RG ~6-6.9 kpc), considering uncertainties, except for ESO 260-7 (RG = 8.9 kpc). These OCs are in a tidally filled regime and are dynamically evolved, since they are much older than their half-mass relaxation times (t/trh ≳ 30) and present signals of low-mass star depletion. We distinguished two groups: those dynamically evolving towards final disruptions and those in an advanced dynamical evolutionary stage. Although we do not rule out that theMilkyWay potential could have made differentially faster their dynamical evolutions, we speculate here with the possibility that they have been mainly driven by initial formation conditions.

Effect of pH on Eosin Y/PAMAM interactions studied from absorption spectroscopy and molecular dynamics simulations Barraza, Luis F.; Zuñiga, Matías; Alderete, Joel B.; Arbeloa, Ernesto Maximiliano; Jiménez, Verónica A. Absorption spectroscopy experiments were carried out to examine the 1:1 supramolecular interaction between Eosin Y (EOS) and low generation G0-G3 poly(amido amine) (PAMAM) dendrimers at neutral and basic media, aimed at gaining insight about the role of pH and dendrimer generation on EOS-PAMAM binding. Our results revealed that EOS complexation is favored under neutral pH conditions, and that the supramolecular interaction strengthens as the dendrimer generation increases. Further molecular-level information regarding EOS-PAMAM systems was obtained from Molecular Dynamics (MD) simulations, Non-Covalent Interaction (NCI) analysis and MM/PBSA binding free energy calculations, which were carried out to examine the role of the generation, charge, and protonation state of PAMAM on the structure, conformation, and preferable interactions with EOS at neutral and basic pH conditions. Theoretical predictions were in high agreement with experimental results, showing that neutral pH allows a faster, deeper, and more stable complexation of the dye within dendrimer cavities, and that higher generation dendrimers induce a larger affinity towards EOS. According to MD results, the binding mode of the dye favors the interaction of the xanthene moiety within internal dendrimer cavities through the establishment of attractive van der Waals contacts. On the other hand, the carboxylate moiety interacts with the outermost dendrimer branches and remains exposed towards the solvent in G0-G2 PAMAM. These results support the validity of using MD simulations as auxiliary tools to deal with supramolecular complexation phenomena involving PAMAM dendrimers as host molecules.

First report of Pseudomicrostroma juglandis (syn. Microstroma juglandis) causing downy leaf spot of walnut in Argentina Lutz, María Cecilia; Sanchez, Aixa Daihana; Vera, Lucas; Scarso, Ana Gabriela; Sosa, María Cristina During October of 2016, diseased trees (2 years-old) of Juglans regia cv. Chandler in Vista Alegre, Neuquen, North Patagonia, of Argentina, showed characteristic downy leaf spot symptoms (disease incidence 80%)...

Relativity of simultaneity in secondary school: an analysis based on the theory of the conceptual fields Otero, Maria Rita; Arlego, Marcelo José Fabián In this paper, we present results about the conceptualization of the relativity of simultaneity and the operational invariants used by high school students. The Theory of Conceptual Fields is adopted to design, analyse and evaluate a didactic sequence to teach the basic aspects of the Theory of Special Relativity in secondary school. Only the situations related to the relativity of simultaneity are analysed here. An inductive categorization is constructed from 256 protocols generated in the implementations carried out in four 11th grade courses (15-16 years) (N = 128) in a public school of Colombia. The categorization identifies the resolutions of the students and the operative invariants that they use in each situation. The results indicate that the proposed situations would produce the emergence and awareness of the operational invariants linked to the relativity of Galileo, which would open the way to the conceptualization of the relativity of simultaneity in secondary school.

Selección de plantas acuáticas y sustratos para el tratamiento de efluentes de predios lecheros utilizando sistemas wetland Schierano, María Celeste; Véliz, Gastón; Gutierrez, Gonzalo; Vianco, Giselle El objetivo del presente estudio fue determinar la combinación ?macrófita + sustrato? óptima para el tratamiento de efluentes de tambo, utilizando wetlands subsuperficiales de flujo horizontal (WSFH) a escala laboratorio. Sedispusieron en un invernadero 16 microcosmos simulando WSFHs con diferentes combinaciones de ?macrófita + sustrato? por duplicado. Se evaluaron dos sustratos: leca y uno combinado, formado por grava y zeolita, y tres especies de macrófitas (Typha domingensis, Phragmites australis y Canna indica), utilizando efluente real de predio lechero con tratamiento previo. A fin de evaluar la eficiencia de los distintos tratamientos, se determinó: pH, conductividad, nitrógeno total Kjeldahl, amonio, nitrato, nitrito, fósforo total, sólidos suspendidos y demanda química de oxígeno (DQO) en el efluente inicial y final de cada tratamiento. Los WSFHs demostraron ser eficientes para tratar el efluente en estudio, determinándose que el sustrato óptimo fue la leca y las macrófitas más eficientes P. australis y T. domingensis.

Mass production studies in solid substrates with the entomopathogenic fungus, Purpureocillium lilacinum Barra, Paula Sabina; Barros, Germán Gustavo; Etcheverry, Miriam Graciela; Nesci, Andrea Verónica The objective of this study was to evaluate several substrates to determine the optimal condition of entomopathogenic mass production with the purpose of developing a mycoinsecticide to be used for an integrated pest management. Conidial quality and yield for two isolates of Purpureocillium lilacinum were determined. For quality parameters assessment, germination and purity percentage and viability of conidia were determined. For the production parameters, the conidial yield was calculated. The main results obtained show the type of substrate that had the greatest effect on the viability, germination and yield of conidia of P. lilacinum. The substrate that presented the highest production of conidia per gram was rice, showing 2.1×109 for isolate JQ926212 and 1.6×109 for JQ926223. In the particulate substrates, the percentage purity was about 99%, while in powder substrate, the percentage purity was low with values ranging from 23 to 75%. The highest percentage of moisture content was about 40% for rice and wheat, while for maize meal and vermiculite the percentage was close to 20%. In conclusion, P. lilacinum can be mass multiplied in rice grains and vermiculite.

La aporía de la técnica y la división empírico-trascendental en La técnica y el tiempo de Bernard Stiegler; The aporia of technics and the transcendental divide in Bernard Stiegler's Technics and Time Vaccari, Andrés En La técnica y el tiempo, Bernard Stiegler busca revitalizar la filosofía de la técnica en su dimensión antropológica y política, estableciendo a ésta como el hilo conductor entre las problemáticas de la conciencia, el tiempo, la materialidad y lo humano. Por otro lado, Stiegler restaura una metafísica de corte tradicional que demarca fi rmes divisiones entre naturaleza y artifi cialidad, humano y animal, así como viviente y no-viviente. En este artículo, me propongo examinar cómo esta ontología conservadora se establece como la condición necesaria de la visión tradicional de la técnica (reduccionista, determinista y esencialista) que Stiegler propone.; In Technics and Time, Bernard Stiegler seeks to revitalize the philosophy of technology in its anthropological and political dimensions, establishing technics as the guiding thread between the problems of consciousness, time, materiality, and the human. On the other hand, though, Stiegler restores a metaphysics of a traditional and conservative character that re-establishes fi rm divisions between nature and arti-fi ciality, human and animal, and living and non-living. In this article, I propose to examine how this conservative ontology is established as the necessary condition of the traditional (reductionist, deterministic, and essentialist) views of technics that Stiegler proposes.

Rural dynamics in Latin American countries. A contemporary analysis Sili, Marcelo Enrique During the past few decades, rural territories in Latin America have experienced profound changes as a result of productive, demographic and social transformations. The changes have been complex, spawning new approaches and points of view in response to the transformations. In the face of increasing complexity, a contemporary analysis of Latin American countries is proposed here. This analysis is based on empirical works and numerous case studies of rural territories in Argentina, Ecuador, Paraguay, Brazil, Mexico, and Chile, as well as a review of rural literature. This analysis contributes to the understanding of the complex processes of rural organization, while also serving as a diagnostic tool to help define public policies that will promote a new type of rural development in the region.

Simultaneous carriage of mcr-1 and other antimicrobial resistance determinants in Escherichia coli from poultry Dominguez, Johana Elizabeth; Redondo, Leandro Martin; Figueroa Espinosa, Roque Arnulfo; Cejas, Daniela; Gutkind, Gabriel Osvaldo; Chacana, Pablo Anibal; Di Conza, José Alejandro; Fernandez Miyakawa, Mariano Enrique The use of antimicrobial growth promoters (AGPs) in sub-therapeutic doses for long periods promotes the selection of resistant microorganisms and the subsequent risk of spreading this resistance to the human population and the environment. Global concern about antimicrobial resistance development and transference of resistance genes from animal to human has been rising. The goal of our research was to evaluate the susceptibility pattern to different classes of antimicrobials of colistin-resistant Escherichia coli from poultry production systems that use AGPs, and characterize the resistance determinants associated to transferable platforms. E. coli strains (n = 41) were obtained from fecal samples collected from typical Argentine commercial broiler farms and susceptibility for 23 antimicrobials, relevant for human or veterinary medicine, was determined. Isolates were tested by PCR for the presence of mcr-1, extended spectrum β-lactamase encoding genes and plasmid-mediated quinolone resistance (PMQR) coding genes. Conjugation and susceptibility patterns of the transconjugant studies were performed. ERIC-PCR and REP-PCR analysis showed a high diversity of the isolates. Resistance to several antimicrobials was determined and all colistin-resistant isolates harbored the mcr-1 gene. CTX-M-2 cefotaximase was the main mechanism responsible for third generation cephalosporins resistance, and PMQR determinants were also identified. In addition, co-transference of the qnrB determinant on the mcr-1-positive transconjugants was corroborated, which suggests that these resistance genes are likely to be located in the same plasmid. In this work a wide range of antimicrobial resistance mechanisms were identified in E. coli strains isolated from the environment of healthy chickens highlighting the risk of antimicrobial abuse/misuse in animals under intensive production systems and its consequences for public health.

Evaluación de caminos de difusión de Al en UAl4; Evaluation of Al diffusion paths in UAl4 Kniznik, Laura; Alonso, Paula Regina; Gargano, Pablo Hugo; Rubiolo, Gerardo Hector Obtenida la estructura de defectos puntuales estables y las concentraciones de defectos en equilibrio térmicopara cada composición de Al del compuesto UAl4 previamente, identificamos en este trabajo los mecanismosmás probables de difusión de Al en UAl4, y analizamos los estados de transición en la difusión de Al en UAl4mediante el método Nudged Elastic Band (NEB) implementado en el código VASP. Calculamos utilizandométodos de primeros principios la variación de la energía total del compuesto en función del camino de difusióndel aluminio, con el objetivo de encontrar los puntos de ensilladura para pasar entre dos posiciones de equilibrioy así obtener el camino de mínima energía para la difusión. Esto nos permitió proponer dos mecanismos másprobables para la difusión de átomos de Al en el lado rico en Al del intermetálico: mecanismo de puente antiestructural(ASB) y mecanismo de vacancia entre sitios primeros vecinos de aluminio Al1 (NN). Al calcular laenergía de migración para ambos mecanismos conseguimos estimar ambas energías de activación. La energíade activación del mecanismo ASB resultó menor que la del mecanismo NN pero el primer mecanismo fue desestimadopor dos motivos: por un lado la energía de activación es la mitad de la observada experimentalmente ypor otro lado, siguiendo la literatura, el mecanismo ASB necesita una concentración umbral de antisitios relativamentealta para que el camino de difusión resulte de largo alcance.En base a todos los resultados y discusiones realizados, proponemos que el mecanismo de difusión de aluminioen UAl4 ocurre por el mecanismo NN con una energía de activación de 1.90 eV que compara relativamente biencon el valor 2.06 eV observado experimentalmente, o con el valor 2.17 eV obtenido previamente utilizando unmodelo semi-empírico.; Once the stable structure of point defects and concentrations of defects in thermal equilibrium were obtained for each composition of Al of the compound UAl4, we identified, in this work, the more likely mechanisms for Al mobility in UAl4, and we analyzed transition states in the diffusion of Al in UAl4 by the Nudged Elastic Band (NEB) method implemented in VASP code. Using first principles methods, we have calculated the compound total energy variation according to the migration path of aluminum, in order to find the saddle points between two equilibrium positions and to obtain the minimum migration energy path. This allowed us to propose two most likely mechanisms for the diffusion of Al atoms in the Al-rich side of the intermetallic: antistructural bridge mechanism (ASB) and vacancy mechanism between first neighbors aluminum Al1 sites (NN). When calculating the energy of migration for both mechanisms we estimated both activation energies. The activation energy of ASB mechanism was lower than the NN mechanism but the first mechanism was dismissed for two reasons: on one hand, the activation energy is half the experimentally observed and on the other hand, according to literature, the ASB mechanism needs a threshold antisite concentration relatively high so that the diffusion path results a long-range one. Based on all results and discussions we propose that the aluminum diffusion mechanism occurs in UAl4 by means of NN mechanism with an activation energy of 1.90 eV which compares relatively well with the experimentally observed value of 2.06 eV, or the value of 2.17 eV previously obtained using a semi-empirical model.

Revisitando el debate sobre la Fragmentación Urbana: Una década y media después de "Splintering Urbanism"; Examine the concept of "urban fragmentation" from a review of the debate on the idea of Splintering Urbanism Kozak, Daniel Matias Desde al menos las últimas tres décadas fragmentación se ha vuelto una palabra recurrente en discursos urbanos. Más allá de las diferentes acepciones que el término pueda tener y los usos que de él puedan hacerse, es evidente que existen manifestaciones físico-espaciales que han motivado la persistencia del debate acerca del carácter fragmentado de las metrópolis contemporáneas. Las nociones de "ciudad archipiélago", "ciudad partida", "cuarteada" (quartered city), "urbanismo astillado" (splintering urbanism), "metropolaridades", por citar sólo unas pocas, apuntan en una misma dirección: el reconocimiento de nuevas formas de separación, o la exacerbación de formas divisorias preexistentes, que en el período contemporáneo parecieran cobrar un creciente protagonismo en la forma y estructura de las ciudades y regiones metropolitanas. Muy a menudo los términos "segregación" y "fragmentación" son utilizados intercambiadamente, como meros sinónimos, sin reparar en las especificidades de cada uno de estos conceptos. De este modo, ambas nociones son diluidas para denotar, genéricamente, algún tipo de separación o división en la ciudad. Sin embargo, si bien es evidente que tanto "fragmentación" como "segregación" intentan dilucidar fenómenos urbanos interrelacionados y frecuentemente simultáneos, su utilización más rigurosa y específica permite alumbrar diferentes facetas de estas cuestiones. El fin de este artículo es examinar el concepto de "fragmentación urbana", a partir de una revisión del debate en torno a la idea de Splintering Urbanism de Graham y Marvin (2001), para apuntar al desarrollo de marcos teóricos específicos.; Over at least the last three decades fragmentation has become a recurring word in urban discourses. Beyond the different meanings that the term may have and the uses that can be made of it, it is clear that there are physical-spatial manifestations that have motivated the persistence of the debate about the fragmented nature of contemporary metropolises. The notions of "archipelago city", "partitioned city", "quartered city", "splintering urbanism", "metropolarities", to name but a few, point in the same direction: the recognition of new forms of separation, or the exacerbation of preexisting divisive forms that in the contemporary period seem to be increasingly prominent in the form and structure of cities and metropolitan regions. Very often the terms "segregation" and "fragmentation" are used interchangeably, as mere synonyms, disregarding the specificities of each of these concepts. In this way, both notions are diluted to denote, generically, some type of separation or division in the city. However, while it is clear that both "fragmentation" and "segregation" attempt to elucidate interrelated and often simultaneous urban phenomena, their more rigorous and specific use allows for different facets of these issues. The purpose of this article is to examine the concept of "urban fragmentation" from a review of the debate on the idea of Splintering Urbanism by Graham and Marvin (2001), to aim at the development of specific theoretical frameworks.

Políticas públicas dirigidas a la economía social y solidaria: Tensiones, alcances y desafíos en la experiencia de San Martín (Argentina, 2016-2017); Public policies aimed at the social and solidarity-based economy. Tensions, scopes and challenges in the San Martín experience (Argentina, 2016-2017) Garcia, Ariel Oscar; Fontanet, Fernando Sebastián Esta investigación se interroga por las formas efectivas que adquiere el asociativismo en las experiencias de economía social y solidaria (ESS) registradas en la Municipalidad de San Martín (Argentina) para el bienio 2016-2017. Desde un enfoque de triangulación metodológica, el trabajo se propone: a) analizar las tensiones entre los ideales de asociativismo propugnado desde las experiencias de ESS y las formas de proceder que se registran en los participantes de la misma; b) describir las formas de intervención estatal en las experiencias asociativas seleccionadas, considerando específicamente fuentes y modalidades de asistencia técnica (financiamiento y de capacitación). La investigación halla una marcada dependencia de los trabajadores asociados a dispositivos del financiamiento estatal. Esta dependencia impide un efectivo esquema emancipatorio, aspecto que se vuelve estructural debido a la carencia de espacios alternativos y/o específicos de comercialización y de financiamiento.; This paper reflects about effective forms that the associativism acquires in the experiences of social and solidarity economy (SSE) registered in the Municipality of San Martin (Argentina) for the lapse 2016-2017. From a methodological triangulation approach, the work is proposed: a) to analyze the tensions between the ideals of associativism advocated from the ESS experiences and the ways of proceeding that are registered in the participants of the same; b) describe the forms of state intervention in the selected associative experiences, specifically considering sources and modalities of technical assistance (financing and training). The research finds a marked dependence on workers associated with state financing devices. This dependence inhibits an effective emancipatory scheme, an aspect that becomes structural due to the lack of alternative and / or specific spaces for commercialization and financing.

Efecto de la sustitución de V por Ti sobre las temperaturas de transformación de fase y el desajuste de red matriz/ precipitado en la superaleación 76Fe-12Al-12V; Effect of V substitution by Ti on the phase transition temperatures and matrix/ precipitates lattice misfit of the 76Fe-12Al-12V superalloy Ferreirós, Pedro Antonio; Alonso, Paula Regina; la Vega, Rubén Darío; Rubiolo, Gerardo Hector Las aleaciones basadas en Fe-Al tienen un potencial considerable como materiales para aplicaciones estructuralesen altas temperaturas. Sin embargo, su insuficiente resistencia a la termofluencia ha sido un obstáculopara su aplicación. La adición de un tercer aleante (Nb, Ti, Zr ó Ta) ha conseguido aumentar su resistencia aaltas temperaturas, pero a costa de una baja ductilidad. En trabajos previos y con el fin de resolver estas deficiencias,investigamos aleaciones ferríticas de Fe-Al-V con precipitación coherente de la fase L21 (Fe2AlV)sobre una matriz A2. Entre las posibles aleaciones, por presentar precipitados L21 de morfología esférica ysin efecto de coalescencia en alta temperatura, seleccionamos la superaleación 76Fe-12Al-12V. Buscamosahora un cuarto aleante capaz de incrementar la temperatura de coexistencia del campo de dos fases A2+L21y en consecuencia la máxima temperatura de aplicación. Encontramos que las secciones isotérmicas del rincónrico en Fe de los diagramas de fases ternarios Fe-Al-V y Fe-Al-Ti poseen campos de fases similares.Además, la relación entre las energías de formación calculadas para los intermetálicos L21 con Ti y V, permitepredecir una temperatura de equilibrio mayor para el Fe2TiAl que para el Fe2VAl. Por lo tanto, seleccionamosal Ti como posible 4to aleante en la superaleación 76Fe-12Al-12V. En este trabajo mostramos que lasustitución del vanadio por titanio incrementa levemente la temperatura máxima de existencia del campo A2+ L21, además el desajuste de red matriz/precipitado es anulado para un contenido de Ti entre 0,5 y 1 % atómicoe incrementado en forma positiva a mayores porcentajes de Ti. Analizamos por otro lado la cinética deengrosamiento de los precipitados L21 hallando que la velocidad aumenta con el agregado de Ti y la morfologíase modifica de esférica a cúbica.; Fe-Al based alloys have a remarkable potential for high temperature structural applications, provided that the limitation of their low creep resistance is solved. Third element addition (Nb, Ti, Zr or Ta) has proven to perform the task, at the expense of a low ductility. In previous works we have investigated ferritic alloys in the Fe-Al-V system with coherent precipitation of the L21 phase (Fe2AlV) in the A2 matrix. Among possible alloys, we chose the 76Fe-12Al-12V superalloy for filing a L21 precipitation with spherical morphology and void coalescence at high temperature. The new task is to find a fourth alloy element in order to increase the temperature equilibrium of the two phases A2+L21 field and consequently the maximum application temperature. Isothermal sections of the Fe rich corner on ternary Fe-Al-V and Fe-Al-Ti phase diagrams have similar phase fields. Besides, by comparing the formation energies between L21 intermetallics of Ti and V, it is expected a higher equilibrium temperature for the Fe2TiAl than for Fe2VAl. Therefore we select titanium as a possible 4th alloy element in the 76Fe-12Al-12V superalloy We show in this work that vanadium substitution by titanium slightly increases the temperature limit for the A2 + L21 phase field while cancelling the lattice misfit between matrix and precipitates for Ti content between 0.5 and 1 at. % and positively increasing it for Ti contents greater than 1 at. %. Besides, we demonstrate that coarsening rate is increased with Ti addition and morphology is modified from spherical to cubic.

MicroscopÍa fototérmica para el estudio de transformaciones de fase; Photothermal microscopy for the study of phase transformations Zaldivar Escola, Facundo; Martinez, Oscar Eduardo; Mingolo, Nelly Se presenta el desarrollo de un novedoso sistema que permite el mapeo con alta resolución espacial de la difusividad térmica en función de la temperatura hasta 1800K. El sistema se basa en una técnica fototérmica recientemente desarrollada por el grupo, consistente en la medición con un láser de prueba de la curvatura inducida por el calentamiento con un láser modulado. La utilización de tecnología de fibras ópticas provee una alta robustez al equipo. Un horno para microscopio permite realizar rampas a velocidad controlada para el estudio de transiciones de fase y la medición de la difusividad térmica en función de la temperatura. Se pueden establecer mesetas para hacer barridos espaciales con resolución microscópica para el estudio de la evolución de las fases o hacer tratamientos térmicos in situ para estudiar luego la distribución espacial de las fases presentes. En este trabajo se presenta un ejemplo, donde la señal es colectada para un punto fijo y para una dada frecuencia de modulación, en función de la temperatura de la muestra. Se diseña para ello un sistema de corrección de enfoque que compensa la deriva térmica generada por la expansión térmica del sistema. El desplazamiento lateral es corregido utilizando un algoritmo de correlación y la imagen de la cámara. Este dispositivo fue utilizado para determinar la transición de fase de una muestra testigo. Estas capacidades se muestran a partir de la determinación de la energía de activación de la transformación de fase amorfo-cristal de una aleación de Fe-B-Si.; A novel system allowing a high spatial resolution mapping of the thermal diffusivity as a function of temperature up to 1800 K is presented. The system is based on a photothermal technique recently developed by the group, consisting in measuring, with a probe laser beam, the curvature induced by local heating with a modulated pump laser. A microscope heating stage was added to perform temperature ramp and soak that can be used for phase transition and thermal diffusivity determinations as functions of temperature. Spatial scans with microscopic resolution can be performed to study phases evolution at constant temperature for in situ thermal treatments and subsequent study of the spatial phase distribution. In this work an example is presented where the signal at a fixed point and constant modulation frequency is collected as a function of the temperature of the sample. A focus correction device was added to compensate for the thermal drift due to the thermal expansion of the system. The lateral displacement was corrected using a cross correlation algorithm and the camera image. This device was used to determine phase transition temperature of a test sample. These capabilities are shown with the determination of the activation energy for the phase transformation glasscrystal of a Fe-B-Si alloy.

Una nueva subespecie de Lymanopoda ferruginosa A. Butler, 1868 del noroeste de Argentina (Lepidoptera: Nymphalidae: Satyrinae); A new subspecies of Lymanopoda ferruginosa A. Butler, 1868 from northwestern of Argentina (Lepidoptera: Nymphalidae: Satyrinae) Pyrcz, Tomasz W.; Núñez Bustos, Ezequiel Osvaldo Se describe e ilustra una nueva subespecie de Lymanopoda ferruginosa del noroeste de Argentina.; A new subspecies of Lymanopoda ferruginosa is described and illustrated from northwestern Argentina.

Differences in the energetics of collagen denaturation in connective tissue from two muscles Latorre, Maria Emilia; Velazquez, Diego Ezequiel; Purslow, Peter The thermal denaturation of collagen the perimysium of intramuscular connective tissue isolated from bovine Semitendinosus (ST) and Perctoralis profundus (PP) muscles was investigated using a range of heating rates in differential scanning calorimetry (DSC) and analyzed by application of the Kissinger–Akahira–Sunose (KAS) and Lumry-Eyring models. Thermograms showed a broadening of endotherms and a shift towards higher temperatures as the thermal scanning rate increased. These features are consistent with the two-step process of a reversible transition between native and unfolded collagen molecules followed by an irreversible transition between unfolded and denatured states. There were small differences between muscles in the onset temperatures of the thermal transitions at heating rates of 0.5 K min −1 , while both the KAS and Lumry-Eyring models yielded similar values for the effective activation energy of the whole two-step process, the Lumry-Eyring model allowed a greater insight into differences in the reversible and irreversible steps between the perimysium both muscles. Reversible unwinding of the triple-helical collagen molecules in the perimysium from ST muscle required more energy than in PP muscle. It is speculated that the presence of large amounts of elastin in the perimysium of ST muscles may influence this due to a protein crowding mechanism, or by affecting the covalent cross-linking of the collagen.

Phase transitions and symmetry energy in nuclear pasta Dorso, Claudio Oscar; Frank, Guillermo Alberto; López, Jorge A. Cold and isospin-symmetric nuclear matter at sub-saturation densities is known to form the so-called pasta structures, which, in turn, are known to undergo peculiar phase transitions. Here we investigate if such pastas and their phase changes survive in isospin asymmetric nuclear matter, and whether the symmetry energy of such pasta configurations is connected to the isospin content, the morphology of the pasta and to the phase transitions. We find that indeed pastas are formed in isospin asymmetric systems with proton to neutron ratios of x = 0.3, 0.4 and 0.5, densities in the range of 0.05 fm−3 < ρ < 0.08 fm−3, and temperatures T < 2 MeV. Using tools (such as the caloric curve, Lindemann coefficient, radial distribution function, Kolmogorov statistic, and Euler functional) on the composition of the pasta, determined the existence of homogeneous structures, tunnels, empty regions, cavities and transitions among these regions. The symmetry energy was observed to attain different values in the different phases showing its dependence on
the morphology of the nuclear matter structure.

Hidrocarburos no convencionales en Argentina: exploraciones en lo profundo, transformaciones territoriales en superficie; Non-Conventional Hydrocarbons in Argentina: Explorations in the Profound, Transformations in the Territories; Hidrocarbonetos não convencionais na Argentina: explorações no profundo, transformações nos territórios Villalba, María Sofía El desarrollo de hidrocarburos no convencionales en Estados Unidos ha generado una revolución en la industria petrolera en el ámbito mundial. Luego, otros países comienzan a explorar sus recursos. La cuenca Neuquina, Golfo San Jorge y, más recientemente, la Austral Magallanes en la Argentina observan desde la década de 2010 el desembarco de la actividad en sus territorios. Estos últimos se transforman económica, social y ambientalmente debido a las nuevas dinámicas que se instalan. Este trabajo busca analizar las principales transformaciones en las ciudades argentinas cercanas a la actividad hidrocarburífera no convencional. Para ello, se trabajó con fuentes primarias, a partir de entrevistas a informantes calificados y fuentes secundarias, principalmente material bibliográfico y de prensa. Se observa que la cuenca Neuquina, pionera en el desarrollo de la actividad, atraviesa las mayores transformaciones en su territorio, sobre todo en la ciudad de Añelo. En cambio, en la cuenca Golfo San Jorge y Austral Magallanes, las incipientes exploraciones en su territorio todavía no generan importantes cambios.; The development of non-conventional hydrocarbons in the United States has generated a revolution in the oil industry worldwide. Then, other countries begin to explore their resources. The Neuquen and the Golfo San Jorge basins, and more recently the Austral Magallanes basin in Argentina have seen since the decade of 2010 the disembarkation of the activity in their territories. The latter are transformed economically, socially and environmentally due to the new dynamics that are installed. This paper seeks to analyze the main transformations in Argentine cities close to the non-conventional hydrocarbons activity. For this, we worked with primary sources, based on interviews with qualified informants and secondary sources, mainly bibliographic and press material. It is observed that the Neuquina basin, pioneer in the development of the activity, goes through the major transformations in its territory, mainly in the city of Añelo. In contrast, the incipient explorations in the territories of the Golfo San Jorge and the Austral Magallanes basins still do not generate important changes.; O desenvolvimento de hidrocarbonetos não convencionais nos Estados Unidos tem gerado uma revolução na indústria petroleira no nível mundial. Depois, outros países começam a explorar seus recursos. A Bacia de Neuquén, Golfo San Jorge e mais recentemente a Austral Magallanes na Argentina observam desde a década do 2010 o desembarco da atividade em seus territórios. Estes últimos se transformam económica, social e ambientalmente devido às novas dinâmicas que se instalam. O trabalho busca analisar as principais transformações nas cidades argentinas próximas à atividade hidrocarbônica não convencional. Para isto se trabalhou com fontes primárias, a partir de entrevistas a informantes qualificados e fontes secundárias, principalmente material bibliográfico e de imprensa. Observa-se que a Bacia de Neuquén, pioneira no desenvolvimento da atividade, atravessa as maiores transformações em seu território, principalmente na cidade de Añelo. Pelo contrário, na Bacia Golfo San Jorge e Austral Magallanes, as incipientes explorações em seu território ainda não geram importantes mudanças.

Dislocando la propiedad. Un análisis sobre usos del espacio en una experiencia colectiva en Rosario, Argentina; Dislocating property. An analysis of the uses of space in a collective experience in Rosario, Argentina Monje, Ana María; Burin, David; Movimiento Trabajadores Autogestionados; Heras Monner Sans, Ana Ines El capitalismo, en tanto realidad histórica, se ha fundado desde una producción del espacio basada en la creación, naturalización y legitimación de lapropiedad privada. No obstante, dicha perspectiva se encuentra en tensióncon otros modos de pensar y hacer la vida que re-significan al espacio comobien de uso común y como lugar para habitar decidiendo en conjunto. Desde una concepción teórica y metodológica situada en la perspectiva de lageografía crítica con aportes de otras disciplinas (filosofía política, historiajurídica y estudios culturales) y una metodología que combina la etnografíacolaborativa y el análisis institucional, este artículo indaga en las prácticas ysentidos acerca del uso del espacio junto a una red de organizaciones denominada ?Movimiento de Trabajadores Autogestionados? (MTA), ubicada en laciudad de Rosario (provincia de Santa Fe, Argentina). Nuestro objetivo radica en poner en visibilidad los modos en que sus participantes usan y deciden sobre el espacio para interpretar los sentidos y orientaciones que surgen dedichos modos, ya que constituyen una forma distinta a la propuesta por elmarco conceptual y de práctica capitalista; As historical reality, capitalism has constructed, over time, practices and notions of space that prioritize, naturalize and legitimate private property. However, this perspective is in tension with other ways of thinking and making social life that re-signify space as a common property and as a place to be inhabited collectively. From the point of view of a theoretical and methodological conception within the perspective of critical geography, with contributions from other disciplines (political philosophy, legal history and cultural studies) and a methodology that combines collaborative ethnographic and institutional analysis, this article explorespractices and meanings regarding the use of space in cooperation with a network of organizations known as “Movement ofSelf-managed Workers” in Rosario, in the province of Santa Fe, Argentina. Our aim is to make visible the ways in which participants make use of and decide over spaceto interpret the meanings and practices that arise, since they differ from the ways proposed by the capitalist conceptual and practice framework.