Diseño, construcción y ensayo de un concentrador solar cilindro parabólico para fines educativos Dellicompagni, Pablo Roberto; Salvo, Aien Weni; Rojas Villena, Mónica Mireya El artículo aborda el estado actual de los sistemas de concentración solar y su aceptación en la generación de energía, destacando cuatro diseños predominantes: torre central, cilindroparabólico, Fresnel lineal y disco parabólico. En el ámbito global, la capacidad instalada de concentración solar en 2021 fue de 6387 MWe, con una disminución del 2% respecto a 2020 debido a la competencia de la energía fotovoltaica. Sin embargo se pronostica un crecimiento prometedor hacia 2050. A nivel nacional, diversos actores como INENCO y LOCE participan en proyectos de concentración solar. Se subraya la integración de esta temática en programas académicos de la Universidad de Salta, incluyendo posgrados y carreras de energías renovables. Este artículo presenta el proceso de diseño, construcción y pruebas de un concentrador solar cilindroparabólico a pequeña escala para calentar agua, desarrollado en la Tecnicatura Universitaria en Energía Solar de Cafayate. Se empleó software de diseño y se utilizaron materiales locales. Las mediciones experimentales demuestran la eficacia del concentrador, alcanzando 70°C con una eficiencia global pico del 30% y un coeficiente de pérdida promedio de 166 (W/m²°C). Además, se evalúa la experiencia de aprendizaje a través de encuestas a los estudiantes involucrados, con enfoque pedagógico, en la transferencia del conocimiento y tecnológico.

Wolbachia dominance influences the Culex quinquefasciatus microbiota Flores, Guillermo Alejandro Máximo; Lopez, Rocio de la Paz; Cerrudo, Carolina Susana; Perotti, Maria Alejandra; Consolo, Verónica Fabiana; Berón, Corina Marta Microorganisms present in mosquitoes and their interactions are key factors affecting insect development. Among them, Wolbachia is closely associated with the host and affects several fitness parameters. In this study, the bacterial and fungal microbiota from two laboratory Culex quinquefasciatus isolines (wild type and tetracycline-cured) were characterized by metagenome amplicon sequencing of the ITS2 and 16S rRNA genes at different developmental stages and feeding conditions. We identified 572 bacterial and 61 fungal OTUs. Both isolines presented variable bacterial communities and different trends in the distribution of diversity among the groups. The lowest bacterial richness was detected in sugar-fed adults of the cured isoline, whereas fungal richness was highly reduced in blood-fed mosquitoes. Beta diversity analysis indicated that isolines are an important factor in the differentiation of mosquito bacterial communities. Considering composition, Penicillium was the dominant fungal genus, whereas Wolbachia dominance was inversely related to that of Enterobacteria (mainly Thorsellia and Serratia). This study provides a more complete overview of the mosquito microbiome, emphasizing specific highly abundant components that should be considered in microorganism manipulation approaches to control vector-borne diseases.

Nanostructured Al-doped maghemite: a low-cost and eco-friendly material tested for methylene blue removal from water and as an accelerator in ammonium nitrate decomposition Cabrera, Alejandra Fabiana; RodrÍguez Torres, Claudia Elena; Stewart, Silvana Jacqueline Maghemite´s properties for roles as removable and reusable catalysts or photocatalysts in reactions that promote green chemistry can be enhanced by doping with other metals. We investigated nanostructured aluminum-doped magnetic iron(III) oxides (AlxFe2-xO3, x = 0.33, 0.67, and 1) synthesized via the autocombustion method and characterized using various techniques. These materials were tested as photocatalysts for methylene blue dye degradation without peroxide and as catalysts for the thermal decomposition of ammonium nitrate. The results revealed that the cubic spinel structure predominates in all compositions. Aluminum doping led to decreased cell parameters and grain size and loss of microgranular structure. Saturation magnetization decreased with aluminum doping, reaching a low value (∼2 emu/g) for x = 1. The optical band gaps were red-shifted with respect to pure maghemite, with values near 2 eV. Among compositions, x = 0.33 showed the best photocatalytic efficiency, closely matching incident light energy (1.95 eV). The highest degradation efficiency was around 37 % after 80 min. The catalytic effect on ammonium nitrate decomposition was strongly correlated with aluminum concentration, turning the reaction exothermic with energy release of 200 and 400 J/g for x = 0.33 and 0.67, respectively.

Viral load in symptomatic and asymptomatic patients infected with SARS-CoV-2: What have we learned? Mozgovoj, Marina Valeria; Didier Garnham, Mercedes Monica; Ferrufino, Cecilia Gabriela Paola; Blanc, Sofia; Fernández Souto, Adriana Beatriz; Pilloff, Marcela Gabriela; Dus Santos, Maria Jose Asymptomatic and presymptomatic patients played a critical role in the maintenance and spread of infection during COVID pandemic. However, conflicting views about the infectiousness of asymptomatic patients have been raised.Identification of asymptomatic cases relies on SARS-CoV-2 genome detection and, in the absence of common epidemiological variables, quantification of viral load (VL) has been proposed as an estimator for SARS-CoV-2 transmission.Comparison of VLs from symptomatic and asymptomatic patients displayed variable results according to the studied population, the experimental design and the sampling, among other variables.The aim of this work was to determine VLs in symptomatic and asymptomatic patients at the time of sampling and to retrospectively determine their relationship with severity of disease and other parameters that affected the course of COVID-19, in two towns located in Buenos Aires, Argentina.Results from our study showed that VLs from symptomatic and asymptomatic patients were significantly different when analyzed globally. In addition, significant differences were found when VLs from each COVID-19 wave were analyzed. In the first wave VLs from asymptomatic patients (log10 8,21 gc/µl) were significantly higher than in symptomatic ones (log10 6,51 gc/µl) while; in the second wave, VLs from asymptomatic patients resulted significantly lower than in symptomatic patients (log10 4,51 gc/µl and log10 5,23 gc/µl, respectively). In the third wave, no significant differences were observed between VLs from both types of patients.Results from this work demonstrated that the screening of both symptomatic and asymptomatic patients was of utmost importance in order to reduce SARS-CoV-2 transmission to communities.

Morphological and molecular characterization of two populations ex situ regenerated from a germplasm bank accession of the wild potato Solanum chacoense Bitter Poulsen Hornum, Anabela; Camadro, Elsa Lucila Abstract Crop wild relatives are conserved in germplasm banks as original accessions or their ex situ regenerated progenies. The commonly used sexual regeneration method in wild potatoes (FAO 2013)—cultivation of 20–25 plants/accession (N), hand-pollination with pollen mixtures when a percentage of the plants are in bloom, and composition of the regenerated accession without controlling the number of seeds provided by each female progenitor—does not consider the action of internal reproductive barriers. However, wild potatoes—mostly diploid and obligate out-crossers—may present internal pre-zygotic, post-zygotic, or both types of complete or incomplete reproductive barriers, which can reduce the efective number of progenitors (Ne) in relation to N. To evaluate possible phenotypic and genetic changes during a sexual reproduction cycle, two regeneration protocols were followed with one accession of Solanum chacoense Bitter: the current one and the proposed by Camadro (2012). The original accession and the two regenerated populations were morphologically and molecularly characterized. Twenty-one morphological characters (quantitative and qualitative) were considered, and the data were subjected to univariate and multivariate analyses. Allele frequencies were calculated for six microsatellite markers (SSR) and compared among populations with a chi-square test (α=0.05). Great morphological variability for morphological phenotypes and four of the six analyzed SSR, as well as changes in allele frequencies (including allele loss) were revealed within and among the three populations. Therefore, it is advisable to consider aspects of reproductive and population genetics in developing regeneration protocols to prevent or reduce the risks of genetic erosion in sexual regeneration cycles

Los Feminismos en la literatura y en la crítica literaria; Feminisms in literature and literary criticism Mallol, Anahí Diana; Chiani, Miriam Neri Abordaremos aquí el impacto que los trayectos y las transformaciones de los feminismos en su conjugación de activismo y producción teórica, especialmente a partir de su más reciente expansión con Ni una menos, operaron sobre diversas instituciones, producciones y modulaciones de la crítica literaria en los últimos años; no solo porque ciertas zonas de la producción literaria son atravesadas por la agenda del feminismo sino porque la literatura recobra, entre los diferentes discursos sociales y artes, un lugar central como lenguaje de la revuelta, de la lucha, del reclamo que va a cercenar las distancias entre arte/vida/política y renovar los modos de intervención de los y las artistas/escritores.; We will address here the impact that the trajectories and transformations of feminism in its conjugation of activism and theoretical production, especially from its most recent expansion with Ni una menos, operated on various institutions, productions and modulations of literary criticism in recent years; not only because fictional texts are permeated by the feminist agenda, but also because literature recovers, among the different social discourses and arts, a central place as the language of revolt, of struggle, of the claim that will close the distances between art/life/politics and renew the modes of intervention of artists/writers.

Quién habla en las literaturas populares: Reflexiones sobre lengua, soberanía y archivo; Who speaks in popular literatures: On language, sovereignty and archive Ennis, Juan Antonio Este trabajo se propone como un aporte a una discusión teórica y política que interroga la relación entre lengua y soberanía en el discurso de las ciencias del lenguaje en su emergencia y consolidación en el siglo XIX, y en el modo en el cual las mismas contribuyen a construir una noción de lo popular, sus modos de manifestación, registro, archivo y análisis, indagando un corpus que comienza en el centro de Europa, en la Alemania del siglo XIX, pero cuyo alcance se indaga hasta las versiones posteriores del mismo discurso en territorio sudamericano. Así, se procurará explorar en este recorrido el modo en el cual las representaciones de las formas legítimas de la expresión popular como depositarias de una tradición valiosa, originaria, reservorio de sentido para la nación establecen al mismo tiempo los rasgos y límites propios de esa legitimidad, con implicancias de orden cultural, lingüístico, moral, en definitiva, (gloto) político, cuyos alcances llegan hasta el presente.; This paper is proposed as a contribution to a theoretical and political discussion that interrogates the relationship between language and sovereignty in the discourse of language sciences in its emergence and consolidation in the 19th century, and the way in which they contribute to build a notion of the popular, its ways of being manifested, registered, stored and analyzed, exploring a corpus which starts in Central Europe, more precisely in 19th century Germany, although it includes also later versions of the same discourse in South American soil. Thus, we will try to explore the way in which the representations of the legitimate forms of popular expression as depositaries of a valuable, original tradition, reservoir of meaning for the nation, establish at the same time the features and limits of that legitimacy, with implications of cultural, linguistic, moral, and ultimately (gloto) political order, whose scope reaches up to the present.

Charge carrier transport in perylene-based and pyrene-based columnar liquid crystals Alves, Alessandro L.; Bernardino, Simone V.; Stadtlober, Carlos H.; Girotto, Edivandro; Farias, Giliandro; do Nascimento, Rodney M.; Curcio, Sergio Fernando; Cazati, Thiago; Dotto, Marta E. R.; Eccher, Juliana; Furini, Leonardo N.; Gallardo, Hugo; Bock, Harald; Bechtold, Ivan H. Electron and hole transport characteristics were evaluated for perylene-based and pyrene-based compounds using electron-only and hole-only devices. The perylene presented a columnar hexagonal liquid crystal phase at room temperature with strong molecular π-stacking inside the columns. The pyrene crystallizes bellow 166 °C, preserving the close-packed columnar rectangular structure of the mesophase. Photophysical analysis and numerical calculations assisted the interpretation of positive and negative charge carrier mobilities obtained from fitting the space charge limited regime of current vs voltage curves. The pyrene-based material demonstrated an electron mobility two orders of magnitude higher than the perylene one, indicating the potential of this class of materials as electron transporting layer.

Sex-Specific Responses to Tacrolimus and Mycophenolate Mofetil in Spontaneously Hypertensive Rats Marañón, Rodrigo Oscar; Moulana, Mohadetheh In recent decades, the roles of tacrolimus and mycophenolate mofetil (MMF) in hypertension have been under discussion. However, the question of whether there are sex-specific responses to these agents has not received enough attention. Aim: To evaluate sex-specific differences in the responses to tacrolimus and mycophenolate mofetil in female (F) and male (M) spontaneously hypertensive rats (SHRs) and evaluate whether T cells contribute to mean arterial pressure (MAP) changes. Methods: Male and female SHRs received either tacrolimus or MMF for 14 days. The rats were implanted with radiotelemeters. MAP was measured chronically; then, circulating and renal infiltrated CD4+, CD8+, T helper 17 (Th17), and T regulatory (Treg) cells were quantified using flow cytometry. Key Findings: Tacrolimus increased MAP only in males, and it decreased CD4+ and CD8+ T cells in both males and females (p < 0.05). The tacrolimus-induced reduction of renal CD4+ and Treg cells was more profound in males. MMF reduced MAP and circulating and renal CD4+ and CD8+ T cells in the male and female rats. MMF also decreased Th17 and Treg cells in both sexes, but the decrease in Th17 was higher in males (p < 0.05) and the reduction in Treg cells was higher in females (p < 0.05). Our findings indicate that the effects of tacrolimus and MMF on renal T cell subsets are sex-specific. Significance: Targeting T cells in hypertension using therapeutic agents may have different effects on men and women; so, the management of hypertension and post-transplant hypertension using these agents should be specified by gender.

Alteración hidrotermal en las rocas volcánicas que hospedan la Veta Norte, proyecto La Josefina, Patagonia Argentina; Hydrothermal alteration in the volcanic rocks that host the Veta Norte, La Josefina project, Patagonia Argentina Bouhier, Verónica Emilia; Lescano, Leticia; Muñoz Schillizi, Rocio La Veta Norte forma parte del sistema de vetas epitermales de baja a intermedia sulfuración del proyecto La Josefina, localizado en el Macizo del Deseado, provincia de Santa Cruz, Argentina y se aloja en rocas volcánicas jurásicas de la Formación Chon Aike. Las descripciones macroscópicas y microscópicas, análisis de difractometría de rayos X y microscopía electrónica de barrido en muestras de testigo corona, permitieron caracterizar las litologías hospedantes y la mineralogía de la alteración hidrotermal asociada a la Veta Norte. Las texturas, las relaciones de corte y las condiciones de estabilidad de los minerales identificados, permitieron establecer una secuencia paragenética con cuatro estadios. En el estadio 1 (E1) la interacción de las rocas volcánicas con fluidos hidrotermales de pH neutro a débilmente alcalino y temperaturas entre ~ 210° y 300°C generó en los alrededores de la veta una alteración representa-da por clorita, pirita, cuarzo y adularia. Durante el estadio 2 (E2) un leve descenso del pH (entre 5 y 6) y de la temperatura de los flui-dos (entre ~ 150° y 250°C) generó condiciones favorables para la formación de illita, illita-esmectita, cuarzo y sulfuros. En el estadio 3 (E3), y a partir de aguas calentadas por vapor, se formó caolinita + calcedonia a temperaturas <190°C y pH ácido. Posteriormente a la actividad hidrotermal, la incursión de aguas meteóricas desestabilizó los minerales previos y se formaron óxidos e hidróxidos de Fe y Mn y carbonatos de Cu, característicos de la alteración supergénica (E4). Caolinita presenta cristalinidad alta en todas las rocas estudiadas, con aumento de la misma en los sectores próximos a la Veta Norte. Illita no es un buen indicador de paleoconductos ya que no presenta una variación clara de su cristalinidad respecto a la estructura mineralizada.

The gates of sleep in Aeneid 6: Falseness, poetry, and history Martinez Astorino, Pablo Leandro Since falsehood, following Hesiod´s tradition (Theog. 26-28), is linked to poetry--as the Muses can utter ψεύδεα πολλά capable of being believed as truth (i. e., plausible, uerisimilia)--, the gate of falsa insomnia crossed by Aeneas hesiodically suggests that the speech of Anchises, the history Virgil chooses to represent in Book 6, is in the realm of false things, though in a literary sense: that is, in the realm of plausible things, of poetry. At issue is history as poetic construction, emphasized especially by: 1. Anchises´ use of the word dicta to make explicit the fata; 2. fertur´s allusion to Homer and the Varronian derivation from fari of the word falsus; 3. the fact that at the very beginning of the book, an artist, Daedalus, sculpts some gates introducing the artistic interpretation for the final image of the gates (continued in the Shield of Vulcan); 4. the use of word uates in the sense of poet, vicariously applied to the mythic poet Musaeus in the catabasis and, immediately (7,41), in the prelude of the "historic" horrida bella. What is a construction to the reader is, for the character Aeneas, a revelation known only in general terms.

La variación en las clases de gramática: Propuesta Didáctica a Partir de la construcción existencial Haber + Sn; The variation in grammar classes: Didactic proposal from the existential construction Haber + Sn Zurlo, Adriana Alicia Este trabajo propone una intervención didáctica sobre aspectos gramaticales del verbo en español para un aula de nivel superior. La secuencia didáctica descrita pretende articular la comprensión de conceptos teórico-prácticos presentes en los materiales de enseñanza (predicado verbal,estructura argumental, cómo identificar y analizar los argumentos de un verbo) con el estudio contrastivo a partir de un pequeño corpus de usos lingüísticos de variedades de español hablado en el Nordeste argentino. Al tener en cuenta el concepto de instrumento lingüístico (Arnoux,2016), argumentamos que la secuencia didáctica en este caso puede ser pensada como un dispositivo normativo, destinado a regular prácticas lingüísticas, modos de leer, interpretar,saber y hacer análisis gramatical, estableciendo las formas correctas y las que no lo son. La investigación se basa en datos provenientes de registros de clases, apuntes y materiales didácticos de elaboración propia, así como las producciones de los estudiantes. La secuencia didáctica implementada involucró distintos momentos, actividades y producciones cuyo foco fue el análisis contrastivo de la construcción verbal haber con valor presentativo-existencial a partir de muestras de habla regionales compiladas por los estudiantes para detectar posibles variaciones. Esperamos que esta descripción de la secuencia didáctica y la reflexión sobre sus alcances puedan contribuir a promover prácticas de enseñanza atentas a la diversidad lingüística local.; This paper proposes a didactic intervention on grammatical aspects of the verb in Spanish for a higher level classroom. The didactic sequence described aims to articulate the understanding of theoretical-practical concepts present in the teaching materials (verbal predicate, argument structure, how to identify and analyze the arguments of a verb) with the contrastive study based on a small corpus of linguistic uses of local varieties of Spanish spoken in Northeast Argentina. Taking into account the concept of linguistic instrument (Arnoux, 2016), we argue that the didactic sequence in this case can also be thought of as a normative device, intended to regulate linguistic practices, ways of reading, interpreting, knowing and doing grammatical analysis, establishing the correct ways and those that are not. The research is based on data from class records, notes and self-made teaching materials as well as student productions. The didactic sequence implemented involved different moments, activities and productions whose focus was the contrastive analysis of the verbal construction haber with presentative-existential value based on regional speech samples compiled by the students to detect possible variations. We hope that this description of the didactic sequence and the reflection on its scope can contribute to promoting teaching practices that are attentive to local linguistic diversity.

Occupational complexity of paid work and housework, and its impact on the cognitive performance in community dwelling older adults, preliminary results; Complexidade ocupacional do trabalho remunerado e o trabalho doméstico e seu impacto no desempenho cognitivo de idosos residentes na comunidade, resultados preliminares Feldberg, Carolina; Barreyro, Juan Pablo; Quián, Maria del Rosario; Hermida, Paula Daniela; Ofman, Silvia Deborah; Irrazabal, Natalia Carolina; Tartaglini, Maria Florencia; Serrano, Cecilia Mariela Work and activity could be an important source of cognitive enrichment. Activities that are more challenging concerning the cognitive functions that are put into practice are associated with lower risk of cognitive decline in old age. Objective: The present study aimed to assess the impact of occupational complexity and household tasks in three cognitive domains (verbal episodic memory, language, and executive functions) in older adults residing within the community. Methods: A trail analysis was executed, using the structural equations procedure in 120 participants assessed with main lifetime occupational activity and household tasks questionnaire, as well as a neuropsychological assessment battery for memory, language, and executive functions. Results: The regression weights analysis indicated that complexity in household chores showed moderate effects on executive functions (β=0.19; p=0.027) and that occupational complexity of paid work showed effects on memory (β=0.26; p=0.008), language (β=0.38; p<0.001), and executive functions (β=0.55; p<0.001). Conclusion: Paid work promotes cognitive reserve, contrary to household activities which seem to have a moderate impact on cognition. Differences in activity complexity not only impact people´s economic and social status and possibilities but can also determine different courses of aging and cognitive risk.; . Trabalho e atividade podem ser importantes fontes de enriquecimento cognitivo. Atividades que são mais desafiadoras quanto às funções cognitivas postas em prática se associam a menor risco de declínio cognitivo em idade avançada. Objetivo: O objetivo do presente estudo é avaliar o impacto da complexidade ocupacional e das tarefas domésticas em três domínio cognitivos (memória episódica verbal, linguagem e funções executivas) em idosos residentes na comunidade. Métodos: Foi realizada uma análise de trilha com o uso de procedimento de equações estruturais em 120 participantes, avaliados por meio de: questionário das principais atividades ocupacionais e tarefas domésticas da vida, bem como bateria de avaliação neuropsicológica para memória, linguagem e funções executivas. Resultados: A análise dos pesos de regressou mostrou que a complexidade nas tarefas domésticas apresenta efeitos moderados nas funções executivas (β=0,19; p=0,027) e que a complexidade ocupacional do trabalho remunerado teve efeitos sobre a memória (β=0,26; p=0,008), linguagem (β=0,38; p<0,001) e funções executivas (β=0,55; p<0,001). Conclusão: O trabalho remunerado promove a reserva cognitiva, em contraste com as atividades domésticas, que parecem ter impacto moderado na cognição. As diferenças na complexidade das atividades não apenas impactam o status econômico e social e as possibilidades das pessoas, mas também podem determinar diferentes cursos de envelhecimento e risco cognitivo.

The spectroscopic orbit of HD 168112 A,B in NGC 6604: another massive binary target for interferometry Putkuri, Cristina Ester; Gamen, Roberto Claudio; Morrell, Nidia Irene; Maíz Apellániz, Jesús; Arias, J. I.; Simón Díaz, S.; Ferrero, Gonzalo Ariel; Rodríguez, C. N.; Sota, A.; Benvenuto, Omar Gustavo; Barba, Rodolfo Héctor We present the first spectroscopic orbit of the O-type double-lined star HD 168112 A,B. We analyse 101 high-resolution optical spectra identifying the absorption lines of both components. The orbital solution presents a relatively long period, P = 513.52 ± 0.01 d, and a high eccentricity, e = 0.743 ± 0.005. The binary system consists of two very similar stars of minimum masses of ~25 M⊙, effective temperatures of ~40 000 K, and surface gravities of ~3.7 dex. The system has a minimum semimajor axis a sin i ~ 1000 R⊙. We confirm that the A and B visual components identified via interferometry do correspond to the spectroscopic ones. We also analyse the underlying stellar groups using Gaia DR3 data and ground-based spectroscopy as part of the Villafranca project, determining that NGC 6604 is at a distance of 1942−36+38" role="presentation">1942+38−36 pc and giving spectral classifications for 23 massive stellar systems in Villafranca O-035 and the surrounding Ser OB2 association, for which we provide the most complete census of massive stars to date.

Fundamental parameters of two O9-type giant stars: the (former) spectral classification standard HD 93249 A and ALS 12502 A Ansín, Tomás; Gamen, Roberto Claudio; Morrell, Nidia Irene; Barba, Rodolfo Héctor; Maíz Apellániz, Jesús; Arias, J. I.; Simón Díaz, S.; Holgado, G. The evolution of massive stars is not completely understood. Several phenomena affect their birth, life, and death, multiplicity being one of them. In this context, the OWN and MONOS projects are systematically observing O- and WN-type stars whose multiplicity status is unknown. Their major goal considers the necessity of determining absolute parameters of massive stars. We have collected spectra of HD 93249 A and ALS 12502 A aiming at characterizing their binary nature. For both stars, we analysed high-resolution spectra and combined them with Transiting Exoplanet Survey Satellite (TESS) observations to be compared with binary models constructed by means of the PHOEBE code. We discovered that the radial velocity of HD 93249 A varies with a period of 2.97968 ± 0.00001 d and that the system presents ellipsoidal light variations. We disentangled the composite spectra and classified its components as O9 III and B1.5 III, respectively. Confirmed as a spectroscopic binary, HD 93249 A can no longer be used as spectral classification standard. ALS 12502 A turned out to be a detached eclipsing binary in the TESS and Gaia data. These results enable us to determine absolute parameters for each component in the system.

Democracia y filosofía como forma de vida Farrán, Roque En este texto me referiré a los tres conceptos principales que definen a la democracia moderna: igualdad, libertad, fraternidad; y lo haré desde una perspectiva filosófica materialista que se asume como forma de vida. El giro práctico que promuevo hace tiempo se nutre de elaboraciones ontológicas, críticas y éticas para pensar nuestro presente. Procederé aquí al modo materialista, trazando demarcaciones conceptuales y adelantando tesis cuyas consecuencias no desarrollaré en extensión porque son cuestiones que vengo presentando en distintos textos y lugares. Así, muestro en acto un modo de pensar que se forja en el entrelazamiento de diversos tópicos y, al finalizar, propongo ejercicios concretos.

La escritura de sí en clave materialista como una revalorización de la práctica filosófica; A escrita de si em chave materialista como uma revalorização da prática filosófica; The writing of the self from a materialist perspective us a revalorization of the philosophical practice Farrán, Roque En este texto pretendo cuestionar la idea habitual que nos hacemos de la escritura académica filosófica y proponer otra más clásica. Se suele usar la escritura como una instancia de comunicación de investigaciones o experiencias previas, pero ¿qué sucedería si consideráramos a la escritura como un ejercicio de pensamiento y formación en acto? La escritura de sí no es literatura del yo ni autobiografía, sino un modo material concreto de constitución de sí a través de la recolección de discursos y enseñanzas de otros (maestros, legados, tradiciones). Por eso deseo recuperar esta función práctica de la escritura de sí que retoman Foucault y Hadot de los antiguos para promoverla como un ethos o incluso método de pensamiento contemporáneo. Por último, propongo algunas meditaciones concretas para ejercitarse. La apuesta de este escrito es revalorizar la escritura académica no solo como comunicación de un estado del saber, sino como riguroso y libre ejercicio de constitución de sí.; Neste texto, pretendo questionar a ideia comum que temos da escrita acadêmica filosófica e propor uma mais clássica. Geralmente, a escrita é usada como uma instância de comunicação de pesquisas ou experiências anteriores, mas o que aconteceria se a considerássemos como um exercício de pensamento e formação em ação? A escrita de si não é literatura do eu nem autobiografia, mas sim um modo material concreto de autotransformação por meio da coleta de discursos e ensinamentos de outros (mestres, legados, tradições). Portanto, desejo resgatar essa função prática da escrita de si, que Foucault e Hadot retomam dos antigos para promovê-la como um ethos ou até mesmo um método de pensamento contemporâneo. Por fim, proponho algumas meditações concretas para a prática. A aposta deste escrito é revalorizar a escrita acadêmica não apenas como comunicação de um estado do conhecimento, mas como um rigoroso e livre exercício de autotransformação.; In this text, I aim to question the usual notion we have of philosophical academic writing and propose a more classical approach. Writing is often used as a means of communicating previous research or experiences, but what if we were to consider writing as an exercise of active thought and self-formation? Writing of the self is not a literature of the self or an autobiography, but rather a concrete material mode of self-constitution through the gathering of discourses and teachings from others (masters, legacies, traditions). Therefore, I wish to reclaim this practical function of writing of the self, as advocated by Foucault and Hadot in their study of the ancients, and promote it as an ethos or even a contemporary method of thinking. Finally, I propose some concrete meditations for practice. The aim of this text is to revalorize academic writing not only as a communication of the state of knowledge but as a rigorous and liberating exercise in self-construction.

Enhanced diversity of aquatic macroinvertebrate predators and biological pest control but reduced crop establishment in organic rice farming Pérez Méndez, Nestor; Martínez Eixarch, M.; Llevat, R.; Mateu, D.; Marrero, Hugo Javier; Cid, N.; Catala Forner, M. Organic farming has been adopted as the main alternative to reduce the environmental impact of intensive agriculture by banning the use of synthetic inputs and bolstering key ecological functions such as biological pest control. Yet the potential cascading effects of farming management on the communities of natural enemies, the provisioning of pest control, and the ultimate impact on crop performance remain poorly explored. This is especially true for semi-aquatic crops such as rice (Oryza sativa, L) that largely depend on aquatic macroinvertebrate predators for biological pest control. Here we performed two consecutive landscape-scale field experiments by combining monthly surveys of macroinvertebrate aquatic predators with both pest predation and seed rice germination trials to assess differences between conventional and organic rice farming in all the above-mentioned issues. Specifically, we selected 6 organic and 6 conventionally managed rice paddies and evaluated differences in i) the diversity of aquatic macroinvertebrate predators (taxa richness and evenness), ii) the infestation level of a seed pest (chironomids larvae), iii) the efficiency of biological pest control provisioning and iv) the impact on germination of rice seeds. Communities of macroinvertebrate aquatic predators were more diverse (taxa richness) and abundant in organic than in conventional fields, yet community evenness was higher in conventionally-managed fields. Accordingly, we found that macroinvertebrate-mediated pest control was markedly more efficient in organic farms during the establishment crop stage. Pest infestation, however, remained also higher in organic farming, most likely because biological pest control in organic fields is not able to outcompete chemical control provided in conventional fields. Finally, the increased infestation level observed in organic fields ultimately resulted in reduced germination rates of rice seeds, thus limiting crop performance. Our results highlight the potential positive effects of pesticide banning in organic rice farming on aquatic macroinvertebrate communities and the consequently improvement of biological pest control provisioning. Yet conditions enhancing biodiversity may also favor pest infestation and ultimately increase crop damage. Management recommendations should therefore account for potential services and disservices associated to organic farming in order to avoid negative yield outcomes for rice farmers.

Belgrano en el Alto Perú: Caracterización histórica e iconográfica de una insignia militar de la Guerra de Independencia del sitio Casas Grandes (Depto. Humahuaca, Jujuy); Belgrano in alto Peru: historical and iconographic characterization of a military badge of the independence war from the casas grandes site (Humahuaca department, Jujuy); Belgrano no alto Peru: caracterização histórica e iconográfica de uma insígnia militar da guerra da independência no sítio de casas grandes (depto. Humahuaca, Jujuy) Acedo, Teresa R.; Leoni, Juan Bautista En esta nota presentamos una insignia militar metálica hallada en el sitio Casas Grandes (Departamento Humahuaca, Jujuy). Tras un tratamiento de limpieza y conservación preventiva se logró identificar leyendas y motivos iconográficos en su anverso, que la vinculan con un regimiento de caballería creado por Manuel Belgrano en 1813 para su campaña hacia el Alto Perú.; In this note we present a metallic military badge found at the Casas Grandes site (Humahuaca Department, Jujuy, Argentina). After a careful cleaning and preemptive curation treatment, captions and iconographic motives on its front could be discerned, suggesting a link between this piece and a cavalry regiment created by Manuel Belgrano in 1813 for his expedition to the Alto Peru.

Belgrano en el Alto Perú: Caracterización histórica e iconográfica de una insignia militar de la Guerra de Independencia del sitio Casas Grandes (Depto. Humahuaca, Jujuy); Belgrano in alto Peru: historical and iconographic characterization of a military badge of the independence war from the casas grandes site (Humahuaca department, Jujuy); Belgrano no alto Peru: caracterização histórica e iconográfica de uma insígnia militar da guerra da independência no sítio de casas grandes (depto. Humahuaca, Jujuy) Acedo, Teresa R.; Leoni, Juan Bautista En esta nota presentamos una insignia militar metálica hallada en el sitio Casas Grandes (Departamento Humahuaca, Jujuy). Tras un tratamiento de limpieza y conservación preventiva se logró identificar leyendas y motivos iconográficos en su anverso, que la vinculan con un regimiento de caballería creado por Manuel Belgrano en 1813 para su campaña hacia el Alto Perú.; In this note we present a metallic military badge found at the Casas Grandes site (Humahuaca Department, Jujuy, Argentina). After a careful cleaning and preemptive curation treatment, captions and iconographic motives on its front could be discerned, suggesting a link between this piece and a cavalry regiment created by Manuel Belgrano in 1813 for his expedition to the Alto Peru.