Goliath catfish Brachyplatystoma Bleeker, 1862 (Siluriformes: Pimelodidae) from the Miocene of Argentina Agnolin, Federico; Bogan, Sergio Brachyplatystoma is a genus of freshwater catfishes endemic of South America that includes one the largest siluriform species of the neotropics. The fossil record of the genus is restricted to the Miocene of Colombia and Venezuela and the extant species are distributed along Orinoco and Amazonas basins. The present works aims to describe a new species of Brachyplatystoma from late Miocene deposits at Entre Ríos Province, Argentina. The present report constitutes the first finding of Brachyplatystoma in the Paleoparaná Basin, which is in agreement with previous hypothesis indicating hydrographic connections of this river basin with the Amazon basin until at least the early late Miocene times.

De las detenciones contravencionales a las prácticas de hostigamiento policial: Reflexiones sobre los cambios y permanencias en los estereotipos de conflictividad policial desde la mirada de jóvenes organizados en la ciudad de Córdoba; About contravention arrests to practices of police harassment: Reflections on changes and continuities in the stereotypes of police conflictivity from the perspective of young people organized of the city of Córdoba Plaza Schaefer, Valeria Se considera que, en la sociedad moderna, el ejercicio de la violencia policial es una consecuencia inevitable de la función de reproducción de un orden social determinado y que, además, para poder cumplir con esa función, necesita realizar un proceso de selección de personas que se presenten como conflictivas. Esto es lo que frecuentemente en la literatura penal y criminológica se refiere como «estereotipo de criminalidad», pero sobre el que existe poca producción acerca de su definición. Por ello, en primer lugar, se analiza el proceso de diferenciación social que opera y las características asociadas al mismo, para indagar luego cuáles son las marcas relevantes en la aplicación del «estereotipo de conflictividad policial» en un caso concreto, según la perspectiva de los mismos destinatarios. Se analiza la mirada de jóvenes de sectores populares organizados sobre la aplicación del estereotipo, nucleados en el Colectivo de Jóvenes por Nuestros Derechos analizando dos momentos distintos (2003–2013 / 2015–2017), a los fines de indagar sobre los cambios y continuidades en esos procesos de estereotipación en la ciudad de Córdoba; It is considered that in modern society, the exercise of police violence is an inevitable consequence of the function of reproduction of a particular social order and also, in order to fulfill that function, you need to carry out a process of selection of people who come forward as conflicting. Tis is what fequently in criminal and criminological literature is referred to as a stereotype of criminality, but about which there is little production about its definition. Terefore, first, the process of social differentiation that operates and the characteristics associated with it is analyzed, to then investigate which are the relevant brands in the application of the police conflict stereotype in a specific case, according to the view of the same addressees. The application of stereotype is analyzed from the look of young people from popular sectors organized, grouped in the Collective of Youth for Our Rights, analyzing two different moments (2003–2013 / 2015–2017), in order to investigate changes and continuities in those processes of stereotyping in the city of Córdoba.

Comparative bone microstructure of three archosauromorphs from the Carnian, late triassic chañares formation of Argentina García Marsa, Jordi Alexis; Agnolin, Federico; Novas, Fernando Emilio The Chañares Formation exhibits one of the most important archosauriform records of early Carnian ecosystems. Here we present new data on the palaeohistology of Chañares archosauriforms and provide new insights into their paleobiology, as well as possible phylogenetically informative traits. Bone microstructure of Lagerpeton chanarensis and Tropidosuchus romeri is dominated by fibro-lamellar tissue and dense vascularization. On the other hand, Chanaresuchus bonapartei is more densely vascularized, but with cyclical growth characterized by alternate fibro-lamellar, parallel-fibered and lamellar-zonal tissues. Dense vascularization and fibro-lamellar tissue imply fast growth and high metabolic rates for all these taxa. These histological traits may be tentatively interpreted as a possible adaptative advantage in front of Chañares Formation environmental conditions.

Adenine DNA methylation, 3D genome organization, and gene expression in the parasite Trichomonas vaginalis Lizarraga, Ayelen; O'Brown, Zach Klapholz; Boulias, Konstantinos; Roach, Lara; Greer, Eric Lieberman; Johnson, Patricia J.; Strobl Mazzulla, Pablo H.; de Miguel, Natalia Trichomonas vaginalis is a common sexually transmitted parasite that colonizes the human urogenital tract causing infections that range from asymptomatic to highly inflammatory. Recent works have highlighted the importance of histone modifications in the regulation of transcription and parasite pathogenesis. However, the nature of DNA methylation in the parasite remains unexplored. Using a combination of immunological techniques and ultrahigh-performance liquid chromatography (UHPLC), we analyzed the abundance of DNA methylation in strains with differential pathogenicity demonstrating that N6-methyladenine (6mA), and not 5‐methylcytosine (5mC), is the main DNA methylation mark in T. vaginalis. Genome-wide distribution of 6mA reveals that this mark is enriched at intergenic regions, with a preference for certain superfamilies of DNA transposable elements. We show that 6mA in T. vaginalis is associated with silencing when present on genes. Interestingly, bioinformatics analysis revealed the presence of transcriptionally active or repressive intervals flanked by 6mA-enriched regions, and results from chromatin conformation capture (3C) experiments suggest these 6mA flanked regions are in close spatial proximity. These associations were disrupted when parasites were treated with the demethylation activator ascorbic acid. This finding revealed a role for 6mA in modulating three-dimensional (3D) chromatin structure and gene expression in this divergent member of the Excavata.

Editorial: Addressing roles for glycans in immunology using chemical biology Macauley, Matthew S.; Rademacher, Christoph; Mariño, Karina Valeria Glycoconjugates, macromolecules containing carbohydrates (glycans) conjugated to proteins or lipids, are a diverse class of biopolymers capable of regulating cell-cell interactions. They are present in a high, natural heterogeneity, which originates from the complex mechanisms involved in their biosynthesis. Genetic and environmental factors determine the ensemble of glycans on any particular cell type, in a non-template encoded manner. As a consequence, the cell surface glycan profile provides a tightly-regulated temporal and spatial signature containing crucial biological information. This information is translated into biological functions by glycan binding proteins (GBPs), also called lectins. Importantly, our immune system is modulated by three major GBP families: C-type lectins, galectins, and Siglecs. The abilities of these GBPs to modulate immune cell function is intimately connected to their ability to differentiate ?self? or ?non-self? glycans from our own cells or pathogens, respectively. Hence, GBP?glycan interactions are critical mediators in immune cell homeostasis. Genetic manipulation of glycan processing enzymes has shed light on the roles of glycans in pathologies such as autoimmune diseases and cancer. However, genetic tools such as genomic manipulation and transgenic animal models have shown to be insufficient to fully untangle the roles of GBP-glycan interactions. Accordingly, recent advances in our understanding of GBPs and how they control immune cell function via glycan recognition has been driven by the development of chemical tools.In this Research Topic, we explore recent work illuminating the various roles of glycans and/or GBPs in controlling immune cell function with special emphasis placed on chemical biology approaches that have been instrumental in such efforts. Potential subjects covered may include:? Immunological roles of Glycan-binding proteins? Glycans as immunomodulators? Development of ligands to probe glycan-binding proteins? Chemical biology approaches to modulate glycan-binding proteins and their glycan ligands? Glycans and synthetic derivatives as novel adjuvants? Glycan-based targeted delivery? Intracellular glycosylation in immune cells? Tissue homing of immune cells mediated by glycans? Glycolipid presentation to immune cells? Glycan-based vaccines? Analytical methods for functional characterization of lectin-glycan interactions

Alexander Von Humboldt y Amado Bonpland: su legado en la revaloración de la historia natural; Alexander von Humboldt and Amado Bonpland: their legacy in the revaluation of natural history Cajade, Rodrigo; Hernando, Alejandra Beatriz La Historia Natural (HN) es una disciplina relevante de las Ciencias Naturales que se encarga de describir a los seres vivos y su ambiente a partir de la observación precisa. Como madre de las ciencias occidentales, sus orígenes se remontan a los escritos de Aristóteles, para atravesar desde entonces la historia de la humanidad brindando conocimientos esenciales para su desarrollo. Luego de su auge entre los siglos XVII y XIX con los viajes exploratorios de los naturalistas europeos a los nuevos continentes, la HN ha perdido valoración en el aporte a la construcción del conocimiento científico. Desde entonces el debate sobre el rol de la HN en las ciencias ha oscilado como un péndulo entre su estimación y desestimación. En esta contribución, presentamos los principales temas de este debate aportando nuestro punto de vista a partir de nuestra experiencia en la revaloración de la historia de la HN, resignificada con la influencia de la obra de Alexander von Humboldt y Amado Bonpland. La especialización de las ciencias, los avances tecnológicos, la pérdida del sentido naturalista y la vinculación con el romanticismo han sido, entre otras, las principales causas que han desacreditado a la HN. Sin embargo, concluimos que la historia nos muestra que la HN ha sido y es fundamental para el crecimiento y desarrollo de la humanidad.; Natural History (NH) is a relevant discipline of the Natural Sciences that describes organisms in their environment from accurate observation. As the mother of Western sciences, its origin dates back to Aristotle’s writings. Since then it crossed human history providing essential knowledge for humanity development. After flourishing between the 17th and 19th centuries due to the exploratory travels of European naturalists to the new continents, NH has lost appreciation in its contribution to scientific knowledge. The debate about its role in sciences has swung like a pendulum between estimation and dismissal. In this contribution, we present the main themes of this debate. We expose our point of view from our experience that revalues the history of NH under the influence of Alexander von Humboldt and Amado Bonpland´ works. The specialization of sciences, technological advances, the loss of the naturalistic sense, and the connection with romanticism have been among, the main causes that have discredited NH. However, we conclude that history shows us that NH has been and is fundamental for the growth and development of humanity.

Recent advances in β-galactosidase and fructosyltransferase immobilization technology Ureta, María Micaela; Martins, Gonçalo Nuno; Figueira, Onofre; Pires, Pedro Filipe; Castilho, Paula Cristina; Gomez Zavaglia, Andrea The highly demanding conditions of industrial processes may lower the stability and affect the activity of enzymes used as biocatalysts. Enzyme immobilization emerged as an approach to promote stabilization and easy removal of enzymes for their reusability. The aim of this review is to go through the principal immobilization strategies addressed to achieve optimal industrial processes with special care on those reported for two types of enzymes: β-galactosidases and fructosyltransferases. The main methods used to immobilize these two enzymes are adsorption, entrapment, covalent coupling and cross-linking or aggregation (no support is used), all of them having pros and cons. Regarding the support, it should be cost-effective, assure the reusability and an easy recovery of the enzyme, increasing its stability and durability. The discussion provided showed that the type of enzyme, its origin, its purity, together with the type of immobilization method and the support will affect the performance during the enzymatic synthesis. Enzymes’ immobilization involves interdisciplinary knowledge including enzymology, nanotechnology, molecular dynamics, cellular physiology and process design. The increasing availability of facilities has opened a variety of possibilities to define strategies to optimize the activity and re-usability of β-galactosidases and fructosyltransferases, but there is still great place for innovative developments.

Effect of the availability of economic resources on cognitive functions and social preferences; Efecto de la disponibilidad de recursos económicos sobre funciones cognitivas y preferencias sociales; O efeito da disponibilidadede recursos económicos sobre as funções cognitivas e preferências sociais Correa, Pablo Sebastián; Mola, Débora Jeanette; Reyna, Cecilia El objetivo de esta investigación fue analizar de manera experimental el efecto de la disponibilidad de recursos económicos sobre funciones cognitivas y preferencias sociales en estudiantes universitarios. Se condujo un estudio con diseño experimental inter-sujetos en el que participaron 60 estudiantes universitarios. Se comparó el desempeño de participantes expuestos a condiciones de altos y bajos recursos económicos en tareas de desempeño cognitivo (inteligencia fluida y control inhibitorio) y de preferencias sociales (Juego del Ultimátum, con ofertas de distinto grado de justicia). En general, los resultados indicaron que no hubo diferencias significativas entre los participantes de las condiciones de bajos y altos recursos económicos en las funciones cognitivas y preferencias sociales. En cambio, hubo diferencias según sexo en el dominio cognitivo. Se discuten los resultados a la luz de investigaciones previas y se reconocen las principales limitaciones.; O objetivo desta pesquisa foi analisar de maneira experimental o efeito da disponibilidade de recursos econômicos sobre as funções cognitivas e preferências sociais de estudantes universitários. Foi realizado um estudo com desenho experimental intra-sujeitos, no qual participaram 60 estudantes universitários. Comparou-se o desempenho dos participantes expostos a condições de altos e baixos recursos econômicos em tarefas de desempenho cognitivo (inteligência fluida e controle inibitório) e de preferências sociais (Jogo do Ultimato, com ofertas de diferentes graus de justiça). Em geral, os resultados não indicaram diferenças significativas entre os participantes de condições de baixa e alta renda nas funções cognitivas e preferências sociais. Por outro lado, houve diferenças segundo o sexo no domínio cognitivo. Se discutem os resultados à luz de investigações anteriores e se reconhecem as principais limitações.; The objective of this research was to analyze experimentally the effect of the availability of economic resources on cognitive functions and social preferences in university students. A study with inter-subject experimental design was conducted. 60 university students participated. The performance of participants exposed to conditions of high and low economic resourceswas comparedin tasks of cognitive performance (fluid intelligence and inhibitory control) and social preferences (Ultimatum Game, with offers of different degrees of justice). In general, the results showed that there were no significant differences between the participants of the conditions of low and high economic resources in cognitive functions and social preferences. In contrast, there were differences according to sex in the cognitive domain. The results are discussed in light of previous research and the main limitations are recognized.

Latest advances in optical frequency combs based on quadratic non-linearity Barturen, Mariana; Benjamin, Maglio; Costanzo Caso, Pablo Alejandro Second-order non-linear susceptibility (χ2) is the cause of many non-linear processes in optics including second harmonic generation, sum frequency generation and difference frequency generation. Optical frequency combs based on χ2, i.e. quadratic frequency combs, hold the promise of reducing the devices power consumption and footprint since χ2 materials present a stronger non-linearity than χ3 materials, which suggests that higher efficiencies can be achieved. In this work, we will revisit the latest quadratic combs experimental advances, concerning power threshold, span and wavelength conversion efficiency.

XMM-Newton and NICER Measurement of the Rms Spectrum of the Millihertz Quasiperiodic Oscillations in the Neutron-star Low-mass X-Ray Binary 4U 1636–53 Lyu, Ming; Zhang, Guobao; Méndez, Mariano; Altamirano, D.; Mancuso, Giulio Cesare; Xiang, Fu-Yuan; Xiao, Huaping We used two XMM-Newton and six Neutron Star Interior Composition Explorer observations to investigate the fractional rms amplitude of the millihertz quasiperiodic oscillations (mHz QPOs) in the neutron-star low-mass X-ray binary 4U 1636?53. We studied, for the first time, the fractional rms amplitude of the mHz QPOs versus energy in 4U 1636?53 down to 0.2 keV. We find that, as the energy increases from ∼0.2 to ∼3 keV, the rms amplitude of the mHz QPOs increases, different from the decreasing trend that has been previously observed above 3 keV. This finding has not yet been predicted by any current theoretical model; however, it provides an important observational feature to speculate whether a newly discovered mHz oscillation originates from the marginally stable nuclear burning process on the neutron-star surface.

Actividades tradicionales y actividades con TIC en la enseñanza y el aprendizaje de la Física: El caso de un estudiante con TDA; Traditional Activities And ICT Activities In The Teaching And Learning Of Physics: A Case Of A Student Whit ADD Domínguez, María Alejandra; Stipcich, Silvia Se comunican avances de una investigación que procura contribuir en el aprendizaje de Física para el caso de un estudiante con TDA. La metodología empleada es el trabajo colaborativo entre diferentes profesionales. Se diseñaron actividades con y sin empleo de simulaciones. Se analiza y compara el tiempo en el que un estudiante con TDA se encuentra en comportamiento físico especial y la cantidad de acciones distractoras. Asimismo se busca conocer el grado de aceptación de las TIC en el aula por el grupo escolar, en especial por el estudiante con TDA y el análisis que realizan de las ventajas y desventajas de tales inclusiones. Los resultados muestran que en la mayoría de las intervenciones que incluyen TIC, en particular, simulaciones integradas en actividades especialmente diseñadas, el estudiante con TDA: disminuye la cantidad de acciones distractoras y el tiempo en el que manifiesta síntomas. El estudiante con el trastorno asume un rol crítico de la implementación. El grupo escolar manifiesta un importante grado de aceptación del uso de TIC en la enseñanza de Física.; This work informs of advances in research that aims to contribute to the learning of Physics in the case of a student with ADD. The employed methodology is that of collaborative work between different professionals. Activities both with and without the use of simulations were designed. The time during which a student with ADD exhibits special physical behaviour is analyzed and compared along with the amount of distracting actions. Additionally, it aims to know to which degree are the ICTs accepted in the classroom by the school group, especially by the student with ADD, and to understand their analysis of the advantages and disadvantages of such approaches. The results show that in most of the interventions involving ICT, in particular those with simulations integrated in especially designed activities, the student with ADD decreases both the amount of distracting actions and the amount of time manifesting symptoms. The student with the disorder takes a critical role in the implementation. The school group shows a high level of acceptance towards the use of ICT in the teaching of Physics.

Uso de TIC’s en el contexto de una enseñanza basada en la investigación; Use of ICT’s in the context of inquiry based learning Gazzola Bascougnet, María Paz; Otero, Maria Rita; Llanos, Viviana Carolina En este trabajo se presentan resultados parciales sobre el uso de TIC’s en el contexto del inquiry based learning, tal como lo propone la Teoría Antropológica de lo Didáctico (TAD). Específicamente nos centramos en el desarrollo de un Recorrido de Estudio e Investigación (REI) codisciplinar. El texto describe el tipo de herramientas utilizadas para colaborar con las actividades de modelización en física y en matemática involucradas en el REI. Se proponen ejemplos sobre cómo fueron utilizadas las TIC’s durante cinco implementaciones realizadas en cursos habituales de la escuela secundaria y se analiza el papel que juegan en una enseñanza basada en el cuestionamiento. Los resultados permiten señalar algunas potencialidades de estas herramientas para ampliar el alcance del estudio así como identificar algunas dificultades de su uso en las aulas.; In this paper we present partial results related to the use of ICT’s in the context of inquiry based learning, as it is proposed by the Anthropological Theory of the Didactic (ATD). Specifically, we focus on developing a co-disciplinary Study and research Path (SRP). The text describes the type of tools used during the implementation to collaborate with the modelling activities in physics and mathematics involved in the RSP. Examples of how ICTs were used during five implementations in regular courses in secondary school are presented, to analyse its role in a study processes based on questioning. The results allow to point out some potentialities of these tools extending the scope of the study as well as to identify some difficulties of its use in the classrooms.

Fotografías de una Identidad Barrial; Photographs of a neighborhood’s identity Funaro, Fernando A partir de una investigación situada en un barrio ferroviario de una ciudad media de la provincia de Buenos Aires, Argentina, se propone un análisis de las relaciones entre los procesos de memoria social, la construcción de identidades urbano-barriales, y la producción y el tratamiento de las imágenes fotográficas. Mediante una investigación en audiovisual, se abordan los usos y la realización de fotografías en las intervenciones críticas de algunos actores sociales referidas a la memoria barrial, que pretenden interpelar narrativas hegemónicas tanto en el plano local como en contextos más amplios. Las imágenes usadas y producidas responden a un conjunto de demandas que reclaman, entre otras, medidas de protección patrimonial en el barrio y la restitución del servicio del tren de pasajeros.; Based on an investigation located in a railway district from an average sized city in the province of Buenos Aires, Argentina, the article suggests an analysis of the relationships between social memory processes and the construction of urban-neighborhood identities, and the production and treatment of photographic images. Through an audiovisual investigation, the uses and the production of photographs are addressed in the critical interventions of some social actors related to the neighborhood history, which intend to interpellate hegemonic narratives both at the local level and concerning broader contexts. Both used and produced images respond to a set of demands that claim, among others, measures of patrimonial protection in the neighborhood and the restitution of the passenger train service.

Step by step evolution of Indeterminate Domain (IDD) transcriptional regulators: From algae to angiosperms Prochetto, Santiago; Reinheimer, Renata Introduction: The Indeterminate Domain (IDD) proteins are a plant specific subclass of C2H2 Zinc Finger transcription factors. Some of these transcription factors play roles in diverse aspects of plant metabolism and development, however the function of most of IDD genes is unknown and the molecular evolution of the subfamily has not been explored in detail. Methods: In this study, we mined available genome sequences of green plants (Viridiplantae) to reconstruct the phylogeny and then described the motifs/expression patterns of IDD genes. Key results: We identified the complete set of IDD genes of 16 Streptophyta genomes. We found that IDD and its sister clade STOP arose by a duplication at the base of Streptophyta. Once on land, the IDD genes duplicated extensively, giving rise to at least ten lineages. Some of these lineages were lost in extant non-vascular plants and gymnosperms, however all of them were retained in angiosperms, duplicating profoundly in dicots and monocots and acquiring, at the same time, surprising heterogeneity in their C-terminal regions and expression patterns. Conclusions: IDD were present in the last common ancestor of Streptophyta. On land, IDD duplicated extensively originating ten lineages. Later, IDD were recruited by angiosperms where they diversified greatly in number; C-terminal and expression patterns accompanying important aspects of plant body evolution.This study provides a solid framework of the orthology relations of green land plant IDD transcription factors, thus increasing the accuracy of ortholog identification in model and non-model species and facilitating the identification of agronomically important genes related to plant metabolism and development.

La cartografía social como posibilidad de reflexión colectiva en contextos de precarización de la vida; Social mapping as a possibility for collective reflection in contexts of precariousness of life; Cartografia social como possibilidade de reflexão coletiva em contextos de precarização da vida Escurra, María Isabel; Rosso, Inés Reflexionar en torno a la construcción de metodologías territorialmente situadas resulta primordial al momento de pensarnos en la práctica extensionista. El Proyecto de Extensión “Nuestro Mapa. Diagnóstico participativo por medio de cartografía social” nos ha obligado a transitar debates que consideramos importantes compartir a la luz de la experiencia y de sabernos parte de un proceso de construcción colectiva de conocimiento que, con sus aciertos y embates, se logró constituir y desarrollar en tramas complejas donde la precarización de la vida y la desciudadanización han adquirido una papel significativo en las últimas décadas. La cartografía social en esta experiencia se ha posicionado como una posibilidad de expresión y transformación en la que la interdisciplina ha cumplido un rol protagónico que es preciso desentrañar. Se presenta como resultado de este proyecto la sistematización envuelta en el desafío que nos propusimos al tornarla también participativa, constituyéndose en la intención de cerrar y de seguir trazando posibles caminos a transitar hacia la reivindicación de derechos en el contexto urbano.; Reflecting on building territorially situated methodologies is essential when thinking about extension practice. The “Nuestro Mapa. Participatory diagnosis through social mapping” Extension Project has forced us to go through discussions that we consider important to share in the light of experience and knowing that we are part of a process of collective construction of knowledge, which, with its successes and mistakes, managed to constitute and develop complex lattices where the precariousness of life and de-citizenization have acquired a significant role in recent decades. Social mapping in this experience has positioned itself as a possibility of expression and transformation in which interdisciplinarity has played a leading role that must be unraveled. The systematization involved in the challenge that we set out to make it also participatory are presented as results of this project, constituting the intention to close and continue tracing possible paths to travel towards the vindication of rights in the urban context.; Refletir sobre a construção de metodologias situadas territorialmente é essencial quando se pensa em prática de extensão. O Projeto de Extensão “Nuestro Mapa. Diagnóstico participativo através da cartografia social” nos forçou a passar por debates que consideramos importantes de compartilhar à luz da experiência e sabendo que fazemos parte de um processo de construção coletiva do conhecimento que, com seus sucessos e erros, conseguiu se constituir e desenvolver em tramas complexas, onde a precarização da vida e a descidadanização adquiriram um papel significativo nas últimas décadas. O mapeamento social nessa experiência se posicionou como uma possibilidade de expressão e transformação na qual a interdisciplinaridade desempenhou um papel principal que é preciso desvendar. A sistematização envolvida no desafio que propusemos tornando-a também participativa é apresentada como resultado deste projeto, constituindo a intenção de fechar e, ao mesmo tempo continuar delineando possíveis caminhos a percorrer na reivindicação de direitos no contexto urbano.

Los medios audiovisuales del centro-sudeste bonaerense en el período 1983-2004; Audiovisual media in the south central area of Buenos Aires Province from 1983 to 2004; Meios audiovisuais do centro da província de Buenos Aires no período 1983-2004 Iturralde, María Eugenia En el presente artículo se analiza la implementación de políticas de comunicación a nivel nacional y su incidencia en ciudades medias del centro-sudeste de la provincia de Buenos Aires. Se tomaron específicamente los casos de Azul, Olavarría y Tandil en el período comprendido desde la asunción de Raúl Alfonsín a la presidencia de la nación (1983) hasta la presentación de los 21 Puntos Básicos por una Comunicación Democrática (2004). La etapa abordada se inscribe en el contexto de profundización de los procesos iniciados con la caída de la matriz estado-céntrica (Cavarozzi, 2002, p. 66), momento en el que desde el plano económico se instauró un sistema de libre mercado que consistió en abrir el comercio interno a la competencia exterior. En lo que respecta a los medios de comunicación, diversos estudios refieren a la existencia de procesos de concentración y extranjerización de la propiedad de estos. El análisis nos deja ver que los medios de las ciudades antes mencionadas siguieron el ritmo sostenido por la re-regulación impulsada a nivel nacional. Las experiencias locales no muestran avances de proyectos sin fines de lucro, sino una fuerte preeminencia de actores del sector privado como prestadores y algunas iniciativas públicas sostenidas por instituciones que se encuentran dentro de la órbita de la Iglesia católica argentina. También se observa el surgimiento de grupos de medios locales, la integración de proyectos radicados en Olavarría a un multimedio de la Ciudad Autónoma de Buenos Aires y la extranjerización de la propiedad de los servicios de cable. En la indagación se optó por una estrategia metodológica de carácter cualitativo. Para la producción de datos se articularon diferentes técnicas y procedimientos: entrevistas abiertas, análisis de documentos y de publicaciones de medios de comunicación consultadas en archivos de las ciudades analizadas. Estas técnicas de producción de información empírica dieron lugar a la interacción y articulación entre datos primarios y datos secundarios.; In this article, we will analyze the implementation of communication policies at the national level and their effect on medium-sized cities in the south central area of Buenos Aires Province. We will specifically look at the cases of Azul, Olavarría, and Tandil during the period stretching from Raúl Alfonsín’s swearing-in as president of Argentina (1983) to the drafting of the 21 Essential Points for Democratic Communication (2004). This era was marked by the entrenchment of processes initiated by the fall of the state-centered matrix (Cavarozzi, 2002, p. 66), which, from an economic perspective, saw the establishment of a free market system that opened domestic trade to foreign competition. In regard to communication media, as various studies have pointed out, their ownership underwent processes of concentration and foreign takeover. Our analysis shows how media outlets in the aforementioned cities kept pace with this nationwide trend towards re-regulation. Local examples reveal no advances in non-profit projects, but rather the prominent role of players from the private sector as service providers and public initiatives backed by institutions in the orbit of the Argentine Catholic Church. We also observed the emergence of local media groups, the integration of projects based in Olavarría to a multimedia company in the Autonomous City of Buenos Aires, and the foreign takeover of cable services. For our study, we opted for a qualitative methodological approach. To produce our data, we combined different techniques and processes: open-ended interviews along with an analysis of documents and publications by different communication media stored in archives in the aforementioned cities. These techniques for empirical information gathering led to the interaction and articulation of primary and secondary sources.; Neste artigo, analisamos a implementação de políticas de comunicação em cidades do Centro da província de Buenos Aires, Argentina; os casos de Azul, Olavarría e Tandil foram tomados especificamente no período desde que Raúl Alfonsín teve assumido até a presidência da Nação - em 1983 - até a apresentação dos 21 Pontos Básicos pra uma Comunicação Democrática - no ano 2004. A etapa analisada faz parte do contexto de aprofundamento dos processos iniciados com a queda da matriz centrada no Estado, quando desde o nível econômico foi estabelecido um sistema de livre mercado que consistia em abrir o comércio interno à concorrência estrangeira. No caso da mídia, vários estudos referem-se à existência de processos de concentração e estrangeirização de sua propriedade. No caso de experiências locais registradas, elas mostram uma forte proeminência de atores do setor privado como fornecedores e algumas iniciativas públicas sustentadas por instituições que estão dentro da órbita da Igreja Católica Argentina. Na análise, foi escolhida uma estratégia metodológica qualitativa. Para a produção dos dados, foram articuladas diferentes técnicas e procedimentos: entrevistas abertas, análise de documentos e publicações na mídia, consultadas em arquivos das cidades analisadas. Essas técnicas empíricas de produção de informações, resultaram na interação e articulação entre dados primários e secundários.

Paracetamol removal by photo-Fenton processes at near-neutral pH using a solar simulator: Optimization by D-optimal experimental design and toxicity evaluation Giménez, Bárbara Natalí; Conte, Leandro Oscar; Alfano, Orlando Mario; Schenone, Agustina Violeta This study discusses the degradation of paracetamol (PCT) by Fenton and photo-Fenton reactions at circumneutral pH with the aid of ferrioxalate and a solar simulator as the light source. The influence of three main operating variables: H2O2 concentration (HP), temperature (T) and radiation level (Rad) on PCT conversion was evaluated with a D-optimal design and a response surface methodology (RSM). The analysis of variance (ANOVA) revealed that Rad and T significantly affected the studied response. The model performance was satisfactory, giving low standard deviation (0.74) and good R2 and adjusted R2 values (0.9997 and 0.9993, respectively). The optimal conditions found for each radiation level were tested. The obtained PCT conversions after 90 min of reaction (75.52 %, 96.88 % and 91.50 %, respectively) were in good agreement with the predicted values (71.28 %, 96.75 % and 92.75 %, respectively). It was observed that the maximum and minimum levels of toxicity (bioluminescence inhibition of Vibrio fischeri bacteria) found in the system were closely related to the maximum and minimum concentrations observed for the reaction intermediaries (hydroquinone and 1,4-benzoquinone). In addition, it was only possible to completely reduce the toxicity of the system after 240 min of reaction when high levels of radiation were applied.

Seasonal variations of Diptera assemblages in urban green patches of Cordoba city, Argentina: Same richness, different composition; Variaciones estacionales de los ensambles de diptera en espacios verdes urbanos de la ciudad de córdoba, argentina: Misma riqueza, distinta composición Montes, Marcela; Silvetti, Luna Emilce; Ferreyra, Mariana; Molina, Silvia Itatí; Díaz, Florentina; Argañaraz, Carina Inés; Battan Horenstein, Moira; Gleiser, Raquel M. Seasonality can have a direct influence on thestructuring of insect communities due to different preferences or tolerances tothe climatic conditions of the species that compose them. The aimof this study was to evaluate seasonal changes in adult Diptera assemblages ofurban green patches in a southern temperate region. Dipterans were sampled fromvegetation with a G-VAC (aspirator) in urban green patches in Córdoba city,Argentina, during the summer and winter of 2014. Overall, dipterans were moreabundant in summer than in winter but globally, their richness was similar. However,richness per site was significantly lower in the winter, reflecting a heterogeneous distribution and higher family turnover during this season. Family composition and/ortheir relative abundances differed between seasons, reflecting the seasonal segregationof several Diptera families in this temperate region of the southern hemisphere.; La estacionalidad puede tener una influencia directa en la estructuración de las comunidades de insectos debido a las distintas preferencias o tolerancias a las condiciones climáticas de las especies que las componen. El objetivo de este estudio fue evaluar los cambios estacionales en dípteros adultos en espacios verdes urbanos. Los dípteros fueron colectados sobre la vegetación con una G-VAC (aspiradora) en espacios verdes urbanos de la ciudad de Córdoba, Argentina, durante el verano e invierno de 2014. Globalmente, la abundancia de dípteros fue mayor en verano que en invierno, mientras que la riqueza fue similar en ambas estaciones. Sin embargo, la riqueza por sitio fue significativamente menor en invierno, reflejando una distribución más heterogénea y un alto recambio de familias en esta estación. La composición de familias y/o sus abundancias relativas difirieron entre estaciones, reflejando la preferencia estacional de varias familias de Diptera en esta región templada del hemisferio sur.

Morphological and molecular characterization of a hybrid zone between Prosopis alba and P. nigra in the Chaco region of northwestern Argentina Vega, Carmen; Teich, Ingrid; Acosta, María Cristina; López Lauenstein, Diego Alejandro; Verga, Aníbal Ramón; Cosacov Martinez, Andrea The Gran Chaco is the largest dry forest in South America. Oneof the key taxa of this biome is the genus Prosopis (Fabaceae)which contains several economically important species. One ofthe characteristics of this genus is its natural capacity toexchange genetic information among congeneric species,generating zones of high morphological and genetic variabilityat contact points. The study and management of these contactareas can contribute to the dynamic conservation of thesenative genetic resources. In this study, we analysed three siteswithin a gradient of land aridity, where P. nigra and P. alba growin sympatry and apparently hybridize. This is the first studyperformed in both, Prosopis pure sites and hybrid swarm,which includes a spatially explicit approach and simultaneouslyanalyses fruit and leaf morphological variation, togetherwith molecular information (microsatellites markers). We performeda multivariate morphological analysis, Bayesian geneticclustering and multivariate associations between geneticand morphological variability in the pure parental populationsand in the hybrid swarm, considering possible spatial autocorrelation.Bayesian cluster analysis revealed two distinct groupscorresponding to each species, differentiating the pure morphotypesfrom sites 1 and 2. Site 3, corresponding to the hybridswarm, was composed of pure P. alba and P. nigra trees andhybrid individuals. We found morphological and molecular evidenceof hybridization between P. alba and P. nigra, and detectednovel phenotypes in the hybrid site.

Mineral dust resuspension under vibration: Onset conditions and the role of humidity Balladore, Federico José; Benito, Jesica Gisele; Uñac, Rodolfo Omar; Vidales, Ana Maria he vibration of dusty surfaces inevitably causes re-entrainment of particles into the atmosphere. Given that movement of mineral dust particles deposited on a surface begins at a critical frequency (fc) and amplitude, an experimental laboratory study was conducted to determine the onset conditions for resuspension of a vibrated granular soil. We determined the resuspension state diagram as a function of frequency and amplitude of a sinusoidal vibration, the granulometry of the dust and the thickness of the soil bed. The mitigation effect of humidity was also evaluated. Critical frequencies ranged between 2.5 and 23 Hz when amplitudes were less than 12 mm. These results were independent of bed thickness and perturbation type. For all particle sizes observed, fc decreased monotonically with A, contrasting with behavior observed for individual particles. In dry samples, fc for large size classes was markedly less when A was greater than 6 mm; while the fc for fine fractions only decreased once amplitudes reached 10 mm. Experiments with wet granular soils demonstrated that wetting above an optimum humidity did not necessarily impede movement and caused agglomeration. This study provides guidelines for managing resuspension of granular soils subjected to vibrations.