Non-native barnacle accelerates the recovery from disturbance of intertidal mussel beds Soria, Sabrina Andrea; Gutierrez, Jorge Luis Ceferino; Palomo, Maria Gabriela The barnacle Balanus glandula is a non-native species inhabiting Argentinian rocky shores. The native mussel Brachidontes rodriguezii forms extensive beds in the mid-intertidal zone of these shores, generating a physical structure that determines the diversity of the assemblage. Yet, this native foundation species is prone to mortality due to disturbances associated with extreme climatic events. The aim of this study was to experimentally investigate the role of early-colonizing, non-native B. glandula in the succession process and the recovery of mussel beds following disturbance. Experimental plots were demarcated in the mussel bed and initially cleared of mussels, to produce exposed rock surfaces similar to those that form after a disturbance event. Half of these plots were kept barnacle-free throughout the experiment by removing all recruiting B. glandula, whereas all recruits were allowed to develop in the remaining plots. Our results showed that mussel cover at the end of the experiment was higher in the plots with barnacles. The plots with and without barnacles followed different successional trajectories, with increasing limpet densities and reduced cover of crustose algae in the presence of barnacles during early successional stages. The results indicate that the presence of B. glandula at the early stages of succession can alter successional dynamics and facilitate the recovery of mussel bed cover after disturbance events. More broadly, this study also shows that non-native species, although frequently considered a ‘nuisance’, can accelerate the recovery of foundation species that characterize entire communities and sustain the greatest share of their diversity.

Comportamiento de larvas de Aedes albifasciatus parasitadas por el Nematodo Strelkovimermis spiculatus Comportamiento de larvas de Aedes albifasciatus provenientes de huevos de diferentes edades, parasitadas por Strelkovimermis spiculatus.

Soil microbial functional profiles of P-cycling reveal drought-induced constraints on P-transformation in a hyper-arid desert ecosystem Gao, Yanju; Tariq, Akash; Zeng, Fanjiang; Sardans, Jordi; Graciano, Corina; Li, Xiangyi; Wang, Weiqi; Peñuelas, Josep Soil water conditions are known to influence soil nutrient availability, but the specific impact of different conditions on soil phosphorus (P) availability through the modulation of P-cycling functional microbial communities in hyper-arid desert ecosystems remains largely unexplored. To address this knowledge gap, we conducted a 3-year pot experiment using a typical desert plant species (Alhagi sparsifolia Shap.) subjected to two water supply levels (25 %–35 % and 65 %–75 % of maximum field capacity, MFC) and four P-supply levels (0, 1, 3, and 5 g P m−2 y−1). Our investigation focused on the soil Hedley-P pool and the four major microbial groups involved in the critical phases of soil microbial P-cycling. The results revealed that the drought (25 %–35 % MFC) and no P-supply treatments reduced soil resin-P and NaHCO3-Pi concentrations by 87.03 % and 93.22 %, respectively, compared to the well-watered (65 %–75 % MFC) and high P-supply (5 g P m−2 y−1) treatments. However, the P-supply treatment resulted in a 12 %–22 % decrease in the soil NH4+-N concentration preferred by microbes compared to the no P-supply treatment. Moreover, the abundance of genes engaged in microbial P-cycling (e.g. gcd and phoD) increased under the drought and no P-supply treatments (p < 0.05), suggesting that increased NH4+-N accumulation under these conditions may stimulate P-solubilizing microbes, thereby promoting the microbial community´s investment in resources to enhance the P-cycling potential. Furthermore, the communities of Steroidobacter cummioxidans, Mesorhizobium alhagi, Devosia geojensis, and Ensifer sojae, associated with the major P-cycling genes, were enriched in drought and no or low-P soils. Overall, the drought and no or low-P treatments stimulated microbial communities and gene abundances involved in P-cycling. However, this increase was insufficient to maintain soil P-bioavailability. These findings shed light on the responses and feedback of microbial-mediated P-cycling behaviors in desert ecosystems under three-year drought and soil P-deficiency.

Arqueología de la arqueología: leer bajo nuestra piel; Archeology of archeology: reading under our skin Alcala Riff, Federico Oscar La arqueología foucaultiana ha pasado por distintas etapas desde su auge en la década de 1960 y actualmente parece constituirse en una especie de pieza de museo un tanto incómoda para el pensamiento contemporáneo: es objeto de cierta veneración, pero al mismo tiempo resulta difícil atribuirle alguna autonomía que no tenga en cuenta a la genealogía o algún otro elemento teórico que la acompañe. El propio Foucault contribuyó parcialmente a ello. Sin embargo, a partir de una aproximación relacionada con la lectura como concepto, se podría arrojar nueva luz sobre esta pieza ineludible del pensamiento occidental y sobre la reflexión vinculada con el archivo en general.; Foucauldian archaeology has gone through different stages since its rise in the 1960s and now seems to be a kind of museum piece that is somewhat uncomfortable for contemporary thought: it is the object of a certain veneration, but at the same time it is difficult to attribute to it any autonomy that does not take into account genealogy or some other theoretical element that accompanies it. Foucault himself partially contributed to this. However, from an approach related to reading as a concept and at the same time recovering a certain material dimension of archaeology in relation to the work on the ground, new light could be shed on this inescapable piece of Western thought and on the reflection linked to the archive in general.

Por una historia profesional y cívicamente responsable: los primeros años de la Nueva Escuela Histórica; For a Professional and Civically Responsible History: The First Years of the New Historical School Galfione, Maria Carla La Nueva Escuela Histórica nucleó a un grupo de historiadores argentinos, desde la segunda década de siglo XX, que, de la mano de un amplio despliegue institucional e importantes proyectos de difusión, buscaban definir con precisión los márgenes de la disciplina. El artículo avanza en la exploración de las condiciones que se establecen para el saber histórico durante los primeros años de la Escuela, considera los supuestos historiográficos que se van asentando y los articula con las pretensiones de asignar a la disciplina un rol protagónico en la vida política de la nación. Allí, la cuestión de la nación cobra protagonismo y, con ella, la consideración específica de la temporalidad en juego, que reconfigura el marco conceptual básico para la comprensión de la historia. A la luz de esas reglas y condiciones, el artículo se detiene en particular en el relato de la historia colonial como una historia elaborada en y para un presente. Se reconoce cómo se ejercitan aquellas normas historiográficas y cómo, en sintonía con la posibilidad de pensar desde un nuevo marco temporal, el historiador se convierte en el agente autorizado para el modelado de la subjetividad requerida por la nación.; The “Nueva Escuela Historica” brought together a group of Argentine historians, from the second decade of the 20th century, who, with a wide institutional deployment and important diffusion projects, sought to define precisely the margins of the discipline. The article advances in the exploration of some of the conditions that are established for historical knowledge during the first years of these school, it considers the historiographic assumptions that are being established and articulates them with the pretensions of assigning a leading role to the discipline in the political life of the nation. In this articulation, the question of the nation became protagonist and, together with it, the possibility of recognizing there the deployment of a specific consideration of temporality, which reconfigures the conceptual framework, basis for the understanding of the history. In the light of these rules and conditions, the article focuses in particular on the account of colonial history as a history elaborated in and for a present. It is recognized how those historiographic norms are exercised there and how, in tune with the possibility of thinking from a new time frame, the historian becomes the authorized agent for the design of subjectivity required by the nation.

Effects of Fermented Goat Milk on Adiposity and Gut Microbiota in a Diet-Induced Obesity Murine Model Márquez, María Antonela; Russo, Matias Irineo; Tomei, Carlos Enrique; Castellano, Patricia Haydee; Puglisi, Edoardo; Medina, Roxana Beatriz; Gauffin Cano, María Paola The administration of goat milk fermented (FGM) with Lactobacillus delbrueckii subsp. indicus CRL1447 and supplemented with different mixes of lactobacilli strains (Mix1: Limosilactobacillus fermentum CRL1446 + Lactiplantibacillus paraplantarum CRL1449 + Lactiplantibacillus paraplantarum CRL1472; Mix2: CRL1446 + CRL1449; Mix3: CRL1446 + CRL1472; and Mix4: CRL1449 + CRL1472) was investigated regarding body weight, metabolic and inflammatory parameters, and gut microbiota (GM) composition in mice fed a high-fat diet (HFD). Body weight gain, adipocyte size, fasting blood glucose, serum triglyceride, and leptin levels were significantly reduced in the group fed FGM+Mix3 compared with the obese mice fed FGM. FGM+Mix2 and FGM+Mix3 modified the GM composition, reversing the dysbiosis caused by the HFD. Although there were no significant changes at the phylum level, the GM composition was significantly changed at the family and genus levels. Results suggest that the administration of FGM+Mix3 improves metabolic and immune profiles in obese mice while positively modulating the GM, therefore attenuating the risk factors associated with obesity.

Structure and large-scale environment of galaxy pairs in the S-PLUS DR4 Cerdosino, María Candela; O'Mill, Ana Laura; Rodriguez, Facundo; Taverna, Maria Antonela; Sodré, L.; Telles, E.; Méndez Hernández, H.; Schoenell, W.; Ribeiro, T.; Kanaan, A.; Mendez de Oliveira, C. In this paper, we use photometric data from the Southern Photometric Local Universe Survey Data Release 4 survey to identify isolated galaxy pairs and analyse their characteristics and properties. Our results align with previous spectroscopic studies, particularly in luminosity function parameters, suggesting a consistent trait among galaxy systems. Our findings reveal a high fraction of red galaxies across all samples, irrespective of projected distance, velocity difference, or luminosity ratio. We found that the proximity of a neighbour to its central galaxy influences its colour due to environmental effects. We also found that central and neighbour have different behaviours: central galaxies maintain a stable red colour regardless of luminosity, while neighbour colours vary based on luminosity ratios. When the central is significantly brighter, the neighbour tends to be less red. According to our division in red, blue, and mixed pairs, we found evidence of galactic conformity. The red pair fractions increase in closer pairs and in pairs of similar luminosity, indicating shared environments promoting red galaxy formation. Analysing local density, the expected colour-density relation is of course recovered, but it is strongly determined by the stellar mass of the pair. In denser environments, the red pair fractions increase, blue pairs decrease, and for the mixed pairs it depends on their stellar mass: more massive mixed pairs decrease their fraction, whereas the less massive ones increase it. These results shed light on the intricate relationship between galaxy pairs, their characteristics, and environmental influences on colour, providing insights into their evolutionary histories.

Temporal dynamics of bacterial populations in recirculating aquaculture systems for sea urchin production; Dinámica temporal de poblaciones bacterianas en sistemas de recirculación para la producción acuícolas de erizo de mar Garcés, Marisa Elisabeth; Rubilar Panasiuk, Cynthia Tamara; Cledón, Maximiliano; Sequeiros, Cynthia Introduction: Sea urchin aquaculture is a rising industry, and in consequence, there is a need to establish optimalculture parameters to ensure the health of the cultured animals.Objective: To evaluate the bacterial counts in the seawater of sea urchin (Arbacia dufresnii) aquaculture recir-culating systems (RAS).Methods: The bacteriological water quality of two RAS containing sea urchins was determined. For approxi-mately two months, weekly water samples were taken. The bacteriological quality was determined by countingtotal aerobic heterotrophic populations, lactic acid bacteria, enterobacterias and genus Vibrio. Physicochemicalparameters were also measured.Results: There was no presence of disease or mortality. Enterobacteria and lactic acid bacteria were not detectedfrom both RAS systems. The number of animals had an important effect on the observed difference in the countof total bacteria and Vibrio spp. In RAS 1 the maximum counts of total bacteria and Vibrio spp. were 2.8 x 105± 1.7 x 105 and 1.45 x 105 ± 3.6 x 104 UFC ml-1, respectively. In RAS 2 total bacteria and Vibrio spp. exhibitedrepetitive behavior over time influenced in part by water exchange and mainly by feeding. The results indicatethat periodic water changes ensure a limited growth of bacterial strains as Vibrio and other bacteria.Conclusions: Our results suggests that the bacterial count levels recorded in this study can be used as a thresholdor safety limit for Arbacia dufresnii aquaculture.; Introducción: La acuicultura de erizos de mar es una industria en auge, y en consecuencia, existe la necesidad de establecer los parámetros de cultivo óptimos para garantizar la salud de los animales en cultivo.Objetivo: Evaluar los recuentos bacterianos en el agua de cultivo de los sistemas de recirculación acuícola (RAS) de erizo de mar Arbacia dufresnii. Métodos: Se determinó la calidad bacteriológica del agua de cultivo de dos RAS que contenían erizos de mar. Durante aproximadamente dos meses, se tomaron muestras de agua semanalmente. La calidad bacteriológica se determinó realizando recuento de las poblaciones heterótrofas aerobias totales, bacterias ácido lácticas, enterobacterias y bacterias del género Vibrio. También se midieron parámetros fisicoquímicos. Resultados: No se observaron patologías ni mortalidad. No se detectaron enterobacterias ni bacterias del ácido láctico en ninguno de los sistemas RAS. El número de animales cultivados tuvo un efecto importante en la diferencia observada en el recuento de bacterias totales y Vibrio spp. En el RAS 1 los recuentos máximos de bacterias totales y Vibrio spp. fueron 2.8 x 105 ± 1.7 x 105 y 1.45 x 105 ± 3.6 x 104 UFC ml-1, respectivamente. En RAS 2 los recuentos de bacterias totales y Vibrio spp. exhibieron un comportamiento repetitivo en el tiempo influenciado en parte por el recambio de agua y principalmente por la alimentación. Los resultados indican que los cambios periódicos de agua aseguran un crecimiento limitado de cepas bacterianas como Vibrio y otras bacterias. Conclusiones: Nuestros resultados sugieren que los niveles de recuento bacteriano registrados en este estudio pueden usarse como umbral o límite de seguridad para la acuicultura de Arbacia dufresnii.

El Boletín de la Biblioteca Pública de la Provincia de Buenos Aires: un instrumento estratégico de gestión y exhibición (1899-1905); The Bulletin of the Public Library of the Province of Buenos Aires: a strategic management and exhibition instrument (1899-1905) Dorta, Ruth Ayelén Se elabora una caracterización del Boletín de la Biblioteca Pública de la Provincia de Buenos Aires, editado entre 1899 y 1905 por Luis Ricardo Fors en el marco de sus funciones como director de la Biblioteca situada en La Plata. Se parte de una breve inscripción del órgano periódico en el campo revisteril decimonónico para, luego, poner la mirada sobre los aspectos materiales y de contenido que configuraron su identidad. A modo de conclusión, se sostiene que el Boletín se constituyó como un hito en la historia institucional del espacio bibliotecario y en la historia de la bibliotecología argentina como disciplina en emergencia. En paralelo, se argumenta que Fors hizo un empleo estratégico de éste dispositivo, tanto en términos institucionales como personales.; A characterization is made of the Bulletin of the Public Library of the Province of Buenos Aires, edited between 1899 and 1905 by Luis Ricardo Fors as director of the Library located in La Plata. It starts from a brief inscription of the periodical organ in the field of magazines from the late 19th century and early 20th century to then look at the material and content aspects that shaped its identity. In conclusion, it is argued that the Bulletin was established as a milestone in the institutional history of the Library and in the Argentine library history science as an emerging discipline. In parallel, it is argued that Fors made strategic use of this device, both in institutional and personal terms.

Environmental benchmarks for the European cement industry Sambataro, Luciano; Bre, Facundo; Ukrainczyk, Neven; Koenders, Eduardus A. B. The urgent need to address climate change has pushed Europe to the forefront of environmental legislation initiatives, such as the Environment Action Program (EAP) within the European Green Deal and the disclosure of Environmental Product Declarations (EPDs) in the construction sector. The cement industry plays a vital role in this transition because it is one of the biggest contributors to greenhouse gas emissions worldwide. EPDs have managed to articulate the environmental information flow across different stakeholders, allowing them to incorporate sustainability design practices at the manufacturing, construction, and design levels. However, current EPDs are deterministically disclosed and lack benchmarks, hindering effective comparison and impeding sustainable material development. To address this challenge, the present research introduces a novel Life Cycle Assessment (LCA)-based probabilistic analysis to develop clinker and cement benchmarks. The proposed method incorporates data from industry reports, environmental databases, and EPDs, to generate the stochastic benchmarks. Moreover, a wide range of environmental performance indicators at a national level in Europe are covered, offering a holistic perspective beyond climate change. The results highlight the benefits of using country-specific environmental benchmarks, reducing the standard deviation of results by 2 to 7 times compared to background datasets. The reduction of clinker content proved to reduce 7 to 9 kg CO2eq/t for every 1% reduction in all countries. However, it also increased other indicators depending on the mineral component used as a replacement, underscoring the need for holistic analysis. The research also exposes discrepancies between EPDs and industry-related data, accentuating the need for stochastic information disclosure to enhance reliability and facilitate decision-making by stakeholders. Another significant contribution of this research is the development of an extensive open-access database, providing a reference for future developments regarding sustainable cement and concrete.

Crónicas de implementación: la política educativa viva; Chronicles of implementation: the live educational policy Alucin, Silvia Vanesa En este artículo construimos breves crónicas de implementación de políticas educativas que apuntan a la inclusión en el nivel medio. El trabajo de campo fue realizado, desde una perspectiva etnográfica, en tres escuelas secundarias de la ciudad de Rosario (Santa Fe), entre 2020 y 2023. En estos establecimientos rastreamos estrategias institucionales delimitadas en el camino de la implementación, la traducción, la apropiación de políticas estatales. Analizaremos tres mecanismos a través de los cuales fueron cobrando vida diferentes planes y programas. Éstos son la toma de posiciones al momento de implementar políticas de distribución y asistencia; los modos de ejercer las políticas de acompañamiento educativo y el aprovechamiento de los recursos que brindan las políticas. De este modo indagamos las diversas formas que toma lo estatal en lo escolar.; In this article we construct short chronicles of the implementation of educational policies aimed at inclusion at the secondary level. The fieldwork was conducted, from an ethnographic perspective, in three secondary schools in the city of Rosario (Santa Fe), between 2020 and 2023. In these establishments we tracked institutional strategies delimited in the route of implementation, translation, appropriation of state policies. We will analyze three mechanisms through which different plans and programs came to life. These are the positions taken at the time of implementing distribution and assistance policies; the ways of exercising educational support policies and the use of the resources provided by the policies. In this way, we investigate the different forms taken by the state in schools.

Border effects on the ground state of an ultrathin magnetic film model Horowitz, Claudio; Loscar, Ernesto Selim In the study of ultrathin magnetic films, one of the most simple and widely studied model is the two-dimensional Ising model with short-range ferromagnetic exchange and long-range antiferromagnetic dipolar interactions (ILRA model). In substrates with periodic boundary conditions, it is well known that the ground state of this system, depending on the strength parameter delta , is given by the antiferromagnetic, the irregular checkerboard and the striped states. In this work, we study the border effects on the ground state. We develop a systematic study on square substrates of size LxL with open boundary conditions focusing our attention on the range 0.35 < delta < 0.75. Our results show that, at intermediate values of delta, none of the configurations present on substrates with periodic boundary conditions correspond to the ground state of the system. Specifically, we find three new kinds of ground states for L<9, which are also our best candidates to be ground state in systems of sizes up to L=100. Also, by means of the same systematic study on a similar short-range model, we analyze which of these ground states is a consequence of the long-range character of the dipolar interactions in the ILRA model.

Bone microstructure of Priosphenodon avelasi (Rhynchocephalia: Sphenodontia): paleobiological implications Cavasín, Sol Aldana; Cerda, Ignacio Alejandro; Apesteguía, Sebastián Sphenodontians are a group of vertebrates with a vast taxonomic diversity and worldwide distribution of their fossils. Although they have been the subject of many studies on their phylogeny and morphology, those focused on their paleobiology are still scarce. We present here the osteohistology of eleven postcranial elements corresponding to a single specimen of Priosphenodon avelasi, an eilenodontine sphenodontian from Cenomanian–Turonian rocks of Río Negro (Argentina). The bone samples described here share a parallel-fibered type of matrix. The degree of vascularization varies in all the samples, but none of them present a significant density of primary vascular canals. Lines of arrested growth were observed in all appendicular elements, being better preserved in the humerus, radius and fibula. Extrinsic fibers were observed only in reduced regions of the cortex of the ulna and in one of the phalanges. The primary bone tissue suggests that the specimen had a relatively low growth rate with alternation between slow and accelerated stages. The latter could explain why this taxon reached the largest sizes of all known sphenodontians.

New insights into the molecular phylogeny, biogeographical history, and diversification of Amblyomma ticks (Acari: Ixodidae) based on mitogenomes and nuclear sequences Uribe, Juan E.; Kelava, Samuel; Nava, Santiago; Cotes Perdomo, Andrea P.; Castro, Lyda R.; Rivera Paéz, Fredy A.; Perea, Silvia; Mans, Ben J.; Gofton, Alexander; Teo, Ernest J. M.; Zardoya, Rafael; Barker, Stephen C. Background: Amblyomma is the third most diversified genus of Ixodidae that is distributed across the Indomalayan, Afrotropical, Australasian (IAA), Nearctic and Neotropical biogeographic ecoregions, reaching in the Neotropic its highest diversity. There have been hints in previously published phylogenetic trees from mitochondrial genome, nuclear rRNA, from combinations of both and morphology that the Australasian Amblyomma or the Australasian Amblyomma plus the Amblyomma species from the southern cone of South America, might be sister-group to the Amblyomma of the rest of the world. However, a stable phylogenetic framework of Amblyomma for a better understanding of the biogeographic patterns underpinning its diversification is lacking. Methods: We used genomic techniques to sequence complete and nearly complete mitochondrial genomes –ca. 15 kbp– as well as the nuclear ribosomal cluster –ca. 8 kbp– for 17 Amblyomma ticks in order to study the phylogeny and biogeographic pattern of the genus Amblyomma, with particular emphasis on the Neotropical region. The new genomic information generated here together with genomic information available on 43 ticks (22 other Amblyomma species and 21 other hard ticks–as outgroup–) were used to perform probabilistic methods of phylogenetic and biogeographic inferences and time-tree estimation using biogeographic dates. Results: In the present paper, we present the strongest evidence yet that Australasian Amblyomma may indeed be the sister-group to the Amblyomma of the rest of the world (species that occur mainly in the Neotropical and Afrotropical zoogeographic regions). Our results showed that all Amblyomma subgenera (Cernyomma, Anastosiella, Xiphiastor, Adenopleura, Aponomma and Dermiomma) are not monophyletic, except for Walkeriana and Amblyomma. Likewise, our best biogeographic scenario supports the origin of Amblyomma and its posterior diversification in the southern hemisphere at 47.8 and 36.8 Mya, respectively. This diversification could be associated with the end of the connection of Australasia and Neotropical ecoregions by the Antarctic land bridge. Also, the biogeographic analyses let us see the colonization patterns of some neotropical Amblyomma species to the Nearctic. Conclusions: We found strong evidence that the main theater of diversification of Amblyomma was the southern hemisphere, potentially driven by the Antarctic Bridge's intermittent connection in the late Eocene. In addition, the subgeneric classification of Amblyomma lacks evolutionary support. Future studies using denser taxonomic sampling may lead to new findings on the phylogenetic relationships and biogeographic history of Amblyomma genus.

El rol de las revistas humorísticas durante la última dictadura argentina Palacios, Cristian Cada vez más insatisfechos con el papel asignado a la historieta como arte de masas y compelidos a intentar reflejar la realidad argentina de aquel entonces, los dibujantes y guionistas argentinos de historietas comenzarán a introducir a partir de los años setenta, en el marco de un contexto de conflictividad social profundamente atravesado por la violencia, una serie de cambios en sus obras que traerá aparejado, entre otras cosas, un salto en la calidad artística, que los llevará a competir en el mercado europeo del momento. En lo que respecta a la historieta humorística o al campo del humor gráfico más propenso, por su propia naturaleza, a la experimentación y al juego respecto de sus propias posibilidades tanto gráficas como narrativas, dichas transformaciones encontrarán su lugar natural en revistas humorísticas. En este trabajo nos proponemos revisar cuál fue el rol de dichas revistas durante la última dictadura argentina (1976–1983), poniendo especial énfasis en los períodos que precedieron y prosiguieron este proceso (años 1972–1976 y 1983–1986), que coinciden, acaso no tan paradójicamente, con el apogeo de algunas de las más representativas. Lo que nos interesa indagar es el rol del humor, entendido aquí como un modo diferenciado de lo cómico, en la constitución de una subjetividad humorística específicamente argentina a la hora de dar cuenta del horror de la coyuntura histórica que aquellos creadores estaban viviendo. Las revistas humorísticas, como veremos, ocuparon un lugar muy especial en la historia de los sujetos y de los modos de subjetivación locales, toda vez que en la constitución de una imagen autoral determinada, dichas publicaciones configuraban también un tipo lector al que dicha imagen apelaba de manera directa.

Notas críticas sobre políticas de comunicación y regulaciones en el capitalismo de plataformas en América Latina; Critical notes on communication policies and regulations in platform capitalism in Latin America Aminahuel, Aimé; Rodríguez, Malvina Eugenia El debate sobre políticas públicas y regulaciones para las plataformas digitales constituye una temática de urgente actualidad para las ciencias de la comunicación. Este artículo tiene como objetivo el abordaje teórico-analítico de dimensiones emergentes en la investigación sobre políticas de comunicación en el capitalismo de plataformas en América Latina. El trabajo se inscribe en un enfoque crítico de la economía política de la comunicación, ofrece un estado del arte e incluye una sistematización bibliográfica de los principales debates sobre Estado, big tech y políticas públicas. Las reflexiones desde las nociones de capitalismo cognitivo y capitalismo de plataformas permiten confrontar los enfoques teóricos instrumentales que caracterizan el estudio de los intermediarios de internet. Asimismo, se esbozan consideraciones orientadas a problematizar los dilemas que plantean las propuestas de regulaciones a partir de una revisión de iniciativas estatales y sentencias judiciales en América Latina. La discusión final aborda los desafíos y las tensiones para la investigación en políticas de comunicación sobre plataformas digitales en América Latina, entre los cuales se destaca la necesidad de construir un mapa de conceptos y actores para el análisis de casos en el campo de la política, la legislación y la economía de la comunicación.; The debate on public policies and regulations for digital platforms constitutes an urgent topic for communication sciences. This article aims to provide a theoreticalanalytical approach to emerging dimensions in research on communication policies in platform capitalism in Latin America. The work is part of a critical approach to the political economy of communication, offers state-of-the-art information, and includes a bibliographic systematisation of the primary debates on the state, big tech, and public policies. Reflections from the notions of cognitive capitalism and platform capitalism allow us to confront the instrumental theoretical approaches that characterise the study of internet intermediaries. Likewise, the paper problematises the dilemmas posed by regulatory proposals based on a review of state initiatives and judicial decisions in Latin America. The final discussion addresses the challenges and tensions for research on communication policies on digital platforms in Latin America, such as the need to build a map of concepts and actors to analyse cases in politics, legislation and economics of communication.

Public opinion about solar radiation management: A cross-cultural study in 20 countries around the world Contzen, Nadja; Perlaviciute, Goda; Steg, Linda; Reckels, Sophie Charlotte; Alves, Susana; Bidwell, David; Böhm, Gisela; Bonaiuto, Marino; Chou, Li Fang; Corral Verdugo, Victor; Dessi, Federica; Dietz, Thomas; Doran, Rouven; Eulálio, Maria do Carmo; Fielding, Kelly; Gómez Román, Cristina; Granskaya, Juliana V.; Gurikova, Tatyana; Hernández, Bernardo; Kabakova, Maira P.; Lee, Chieh Yu; Li, Fan; Ortiz, María Victoria; Argüello Pitt, Maria; Reyna, Cecilia; Schuitema, Geertje; Shwom, Rachael; Yalcinkaya, Nur Soylu; Spence, Elspeth; Sütterlin, Bernadette Some argue that complementing climate change mitigation measures with solar radiation management (SRM) might prove a last resort to limit global warming to 1.5 °C. To make a socially responsible decision on whether to use SRM, it is important to consider also public opinion, across the globe and particularly in the Global South, which would face the greatest risks from both global warming and SRM. However, most research on public opinion about SRM stems from the Global North. We report findings from the first large-scale, cross-cultural study on the public opinion about SRM among the general public (N = 2,248) and students (N = 4,583) in 20 countries covering all inhabited continents, including five countries from the Global South and five ‘non-WEIRD’ (i.e. not Western, Educated, Industrialised, Rich, and Democratic) countries from the Global North. As public awareness of SRM is usually low, we provided participants with information on SRM, including key arguments in favour of and against SRM that appear in the scientific debate. On average, acceptability of SRM was significantly higher in the Global South than in the ‘non-WEIRD’ Global North, while acceptability in the ‘WEIRD’ Global North was in between. However, we found substantial variation within these clusters, especially in the ‘non-WEIRD’ Global North, suggesting that countries do not form homogenous clusters and should thus be considered individually. Moreover, the average participants’ views, while generally neither strong nor polarised, differed from some expert views in important ways, including that participants perceived SRM as only slightly effective in limiting global warming. Still, our data suggests overall a conditional, reluctant acceptance. That is, while on average, people think SRM would have mostly negative consequences, they may still be willing to tolerate it as a potential last resort to fight global warming, particularly if they think SRM has only minor negative (or even positive) impacts on humans and nature.

A glimpse inside materials: Polymer structure – Glass transition temperature relationship as observed by a trained artificial intelligence Miccio, Luis Alejandro; Borredon, Claudia; Schwartz, Gustavo A. Artificial neural networks (ANNs), a subset of Quantitative Structure-Property Relationship (QSPR) methods, offer a promising avenue for addressing challenges in materials science. In particular, ANNs can learn intricated patterns within the experimental data, enabling them to predict properties and recognize complex relationships with remarkable accuracy. However, the opacity of ANNs, normally acting as black boxes, raises concerns about their reliability and interpretability. To enhance their transparency and to uncover the underlying relationships between chemical features and material properties, we propose a novel approach that employs Gradient-weighted Class Activation Mapping (Grad-CAM) applied to Convolutional Neural Networks (CNNs). By analyzing these attention maps, we identify the crucial chemical features influencing the prediction of a polymer property, specifically the glass transition temperature (Tg). Our methodology is validated using a dataset of atactic acrylates, allowing us to not only predict Tg values for a control group of polymers but also to quantitatively assess the impact of individual monomer structural elements on these predictions. This work proposes a step towards transparent models in materials science, contributing to a deeper understanding of the intricate relationship between chemical structures and material properties.

Development of antibacterial magnetic clay-based nanocomposites for water treatment Horue, Manuel; Barraqué, Facundo; Montes, María Luciana; Zelaya Soulé, María Emilia; Fernández Morantes, César; Urruchua, Florencia Camila; Correa, Hilda Edith; Castro, Guillermo Raul; Fernandez, Mariela Alejandra Organoclays were prepared using Argentinean montmorillonite (Mt), hexadecyltrimethylammonium, or benzalkonium chloride at different concentrations. Surfactant incorporation, a key factor in biocide capacity, was estimated using interlayer space and thermogravimetric analysis (TGA). Subsequently, Fe oxides were grown on the organoclays. Saturation magnetization indicated that all magnetic composites could respond to an external magnetic field. Inhibition experiments showed high antibacterial activity against Enterococcus faecium, Escherichia coli, and Salmonella typhimurium. The synthesized nanocomposites loaded with 150% CEC (cation exchange capacity) of hexadecyltrimethylammonium were the most effective. Those results were more precisely investigated using the viable plate count method. The magnetic materials had a similar antimicrobial effect to those without magnetic properties, indicating that Fe oxides can be nucleated to impart a magnetic response without affecting the biocide properties. The organoclays showed higher antibacterial activity against E. coli than against the other bacteria assayed. In addition, the agar disk-diffusion method revealed that antimicrobial agents were not released from clays, which is a relevant fact in the water treatment process.

Hydrologic remobilisation of tephra‐fall deposits: A sedimentological analysis throughout fluvio‐lacustrine systems of North‐West Patagonia Losano, Nahuel Ezequiel; Villarosa, Gustavo; Beigt, Debora; Amat Morales, Pablo Nicolas; Cottet, Julieta; Outes, Ana Valeria This paper explores the response to Holocene ash inundation in different sub-environments of two fluvio-lacustrine systems, Las Piedritas and Totoral, focussing on the processes of volcaniclastic remobilisation. Sediment cores and outcrops were used to recognise three deposit types, noting how some differ from lahars, through sedimentological and stratigraphic analysis: (1) thick, laterally discontinuous, pumice-dominated deposits occur overlying alluvial plain and lower terrace surfaces across both watersheds; (2) chaotic, extremely poorly sorted and matrix-supported beds composed of both epiclastic and pyroclastic material occur as two conspicuous deposits at Las Piedritas outcrops, in a low-gradient confined channel setting; and (3) layers with an exclusively pyroclastic composition and no flow sedimentary structures or fragment roundness were found draping each of the two chaotic intervals and intercalating with the background sediment in Las Piedritas prodelta. Thick pumice packages capping the floodplains resulted from the overflow of streams carrying a floating pumice load. Due to its positive buoyancy, the pumice is transported as a slowly moving overlying mantle without mixing with the streamflow. The disorganised pattern and poor sorting of the matrix-rich polymictic beds are consistent with laminar, gravity-driven, high-concentration flows. They constitute secondary lahars, originating upstream from large run-off processes that reworked a pyroclastic substrate. The lack of reworking features in the vitric-rich units identified in the lake core retrieved from Las Piedritas prodelta, as well as the continuous and widespread occurrences of those interbedded in upstream outcrops, indicate an airfall origin. No reworked tephra unit is recognised in the prodelta sediment record, although various deposits from the hydrologic remobilisation of airfall tephra are found along the subaerial portion of both watersheds. Apparently, large amounts of flotation-remobilised tephra were retained on the delta plain, while another considerable fraction would have been carried away from the creek mouth under the influence of dominant regional winds.