Ciencia y Tecnología

Catastro de cavidades de la zona de Malargüe

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Catastro de cavidades de la zona de Malargüe La información que contiene este cuadro fue publicada en un medio de circulación acotada por la Federación Argentina de espeleología (FAdE) con sede en Malargüe. Es posible que en algunas localizaciones existan errores de coordenadas. este registro es útil a los fines de conocer cuantitativamente las cavernas y aleros identificados en el departamento de Malargüe. En el artículo "Malargüe (Argentina): extractivismo y disputa por bienes comunes" se aborda de forma secundaria la relevancia de la espeleología en el sur mendocino y su estrecha relación con la circulación de agua.

Plataformas petroleras costa este río Grande I (Malargüe)

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Plataformas petroleras costa este río Grande I (Malargüe) Relevamiento por medio de la herramienta Argenmap (IGN) de las plataformas petroleras existentes en el este del río Grande (Malargüe). Se midieron el perímetro y superficie de las plataformas y sus correspondientes centroides. Se contabilizaron un total de 571 plataformas (puede haber un límite de error en el conteo).

Plataformas petroleras zona Cerro Fortunoso (Malargüe)

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Plataformas petroleras zona Cerro Fortunoso (Malargüe) Relevamiento efectuado usando la herramienta de Argenmap (IGN) para contabilizar y medir las plataformas petroleras en el área de Cerro Fortunoso (Malargüe) en cercanías del área protegida provincial de La Payunia. Esta información se triangula con trabajo de campo donde se obtuvieron entrevistas con habitantes que crecieron en las inmediaciones y fotografías de la infraestructura que es parte de la actividad hidrocarburífera. En este lugar se contabilizaron (puede haber un límite de error) 234 plataformas. Se identifico su centroide y se midieron las superficies y perímetros.

Competitive ability of three native grass species during establishment

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Competitive ability of three native grass species during establishment Scarfó, María Cecilia; Rodriguez, Dana Aylen; Milano, Clara; Loydi, Alejandro Weed resistance is highly desirable in seed used for restoration. Therefore, assessing the competitiveness of target species during germination and establishment stages would help to plan effective restoration projects. Our study aims to assess the impact of competition in seedling establishment, height, leaf number, and aerial biomass of three native perennial forage grasses with different seed sizes. We conducted a competition experiment under greenhouse conditions with three native species Nassella longiglumis, N. tenuis and Piptochaetium napostaense), and one exotic annual species (Avena barbata). Two competition levels were established (with and without A. barbata) and two seeding densities for the perennial species were defined (15 and 30 seeds per pot). Established seedlings, leaf number, height and aerial biomass were measured. Seedling establishment was affected by competition only for N. tenuis. For all three species, N. longiglumis, with the larger seed size, was the least affected by competition. Competition reduced seedling biomass for all three species, with N. longiglumis, with the larger seed size, being the least affected. Increasing seeding density has little effect on the aerial biomass of the weed.The co-occurrence of native perennial species and the annual species A. barbata severely reduces growth, therefore it is important to implement management practices to control annual exotic species and effectively restore grassland ecosystems.

Fumonisins in infant cereals marketed as complementary food in Argentina

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Fumonisins in infant cereals marketed as complementary food in Argentina Cendoya, Eugenia; Nichea, Maria Julia; Romero Donato, Cindy Johana; Zachetti, Vanessa Gimena Lourdes; Monge, Maria del Pilar; Ramirez, Maria Laura Infant cereals are typically the first foods introduced as complementary foods. Cereals used to elaborate complementary foods, such as wheat, maize and rice, are susceptible to mycotoxin contamination. Among mycotoxins, fumonisins have been epidemiologically associated, in humans, with oesophageal cancer, neural tube defects and stunting. Fumonisins have been found in maize and wheat grains in Argentina. In the present study, a survey was conducted to determine their occurrence in 82 wheat-based and multicereal-based infant cereal items collected from retail stores in Rio Cuarto, Argentina, using HPLC-MS. Of these samples, 84% showed FBs contamination with levels ranging from 0.05 to 992 μg/kg). Although FB1 was the most prevalent fumonisin, FB2 was found at higher levels. Most samples had levels below the limit of 200 μg/kg set for Argentinean cereal products for children. The outcome of this survey provides information on the naturally presence of fumonisin in infant cereal intended for children in Argentina, which can be helpful to consider relevant monitoring programmes.

Stuck between rivers: a new species of Ctenomys from northern Argentine Patagonia

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Stuck between rivers: a new species of Ctenomys from northern Argentine Patagonia Mapelli, Fernando Javier; Esquenazi, Sofía Micaela; Teta, Pablo Vicente; Austrich, Ailin; Kittlein, Marcelo Javier; Pereyra Villaurreta, Maria Daniela Renée; Tammone, Mauro Nicolás; Mora, Matias Sebastian Ctenomys (tuco-tucos) is one of the most speciose genera of mammals, with around 70 described species. Recently, therate of new species descriptions within the genus Ctenomys has notably increased, primarily due to recent taxonomic revisionsand surveys in previously unexplored geographic areas. In this study, utilizing both morphological and molecularevidence, we describe a new species of Ctenomys from northern Argentine Patagonia, confined between the Colorado andNegro rivers. This new species is a member of the Magellanicus group displaying close relationships with other speciesdistributed in northern Patagonia and adjacent regions (C. bidaui, C. miguelchristie, C. pontifex, and C. pulcer). The majorrivers in the region (Colorado and Negro rivers) appear to delineate the distributional boundaries of the identified taxa. Wetherefore propose that rivers, acting as natural barriers to dispersal, have significantly influenced the diversity of Ctenomysin northern extra-Andean Patagonia.

Temporal host–symbiont dynamics in community contexts: Impacts of host fitness and vertical transmission efficiency on symbiosis prevalence

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Temporal host–symbiont dynamics in community contexts: Impacts of host fitness and vertical transmission efficiency on symbiosis prevalence Gundel, Pedro Emilio; Ueno, Andrea Celeste; Casas, Cecilia; Miller, Tom E. X.; Perez, Luis Ignacio; Cuyeu, Romina; Omacini, Marina Symbiotic associations play a role in plant ecology and evolution, but the outcome of the interaction depends on the life-history traits of the partners and the environmental context. Although symbiosis with vertically transmitted microorganisms should result in mutualism, it is not clear how the transmission process aligns with the outcome of the context-dependent symbiosis. For 3 years, we sampled individuals of an annual plant species that forms symbiosis with a vertically transmitted fungal endophyte, in paired stands of two contrasting vegetation communities (humid mesophytic meadows [HMM]: productive/low stress, and humid prairies [HP]: less productive/high stress). We estimated the prevalence of symbiosis at the population level, and the fitness of the plant, the symbiotic status and vertical transmission efficiency at the individual level. Over 3 years, the prevalence of symbiosis was ≈100% in HMM and ≈75% in HP. Plant fitness was very low and high in years with precipitation below and above the yearly mean, respectively. The higher fitness of endophyte-symbiotic plants was evident in the HMM and high precipitation years. Vertical transmission of endophytes was higher in HMM (≈96%) compared to HP (≈93%) and was not related to plant fitness. Despite transmission inefficiencies in HP, changes in prevalence within the growing season (from seeds to the final plant stand) suggest a fitness advantage for symbiotic plants. Vertical transmission is expected to promote mutualism as it aligns partners' fitness. Although symbiotic plants showed higher fitness and the probability of transmission failures was higher among low-fitness plants, the variation in transmission efficiency between plants and vegetation communities was not related to the fitness of the individual host. Our study provides evidence that context-dependent vertical transmission efficiency and endophyte-mediated fitness advantages interact complexly to determine the prevalence of symbiosis in populations that occur in contrasting vegetation communities.

Interplay of virulence factors and signaling molecules: albumin and calcium-mediated biofilm regulation in Bordetella bronchiseptica

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Interplay of virulence factors and signaling molecules: albumin and calcium-mediated biofilm regulation in Bordetella bronchiseptica Mugni, Sabrina Laura; Ambrosis, Nicolás Martín; O'Toole, George; Sisti, Federico Bernardo; Fernandez, Julieta Bordetella bronchiseptica, a respiratory pathogen capable of infecting various mammals, including humans, is associated with chronic infections, contrasting with the acute infections caused by Bordetella pertussis. Both pathogens can form biofilm-like structures in vivo, providing tolerance against environmental stresses. Biofilm formation by B. bronchiseptica is regulated by the BvgAS two-component system, with intermediate concentrations of certain modulators inducing a phase favoring biofilm formation. Recent studies have highlighted the role of cyclic diguanylate monophosphate (c-di-GMP) in this process: elevated c-di-GMP levels stimulate biofilm formation, whereas phosphodiesterase (PDE) activation reduces biofilms. Respiratory secretions, which contain albumin and calcium at higher concentrations than standard growth media, promote an increase in the amount and extracellular localization of the adenylate cyclase toxin (ACT), an important Bordetella spp. virulence factor. Secreted ACT present in the extracellular media or attached to the outer membrane inhibits biofilm formation. Based on these observations, we hypothesized that serum albumin and calcium together inhibit biofilm formation and explored the potential role of c-di-GMP in this process. Our findings demonstrate that serum albumin and calcium inhibit B. bronchiseptica biofilm formation by two apparently independent mechanisms, increasing AC secretion and inducing c-di-GMP degradation. This study contributes to the understanding of the mechanisms governing B. bronchiseptica biofilm formation and its modulation by host factors.

Li decorated graphdiyne nanosheets: A theoretical study for an electrode material for nonaqueous lithium batteries

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Li decorated graphdiyne nanosheets: A theoretical study for an electrode material for nonaqueous lithium batteries Jiménez, María Julia; Juan, Julián; Sandoval, Mario German; Bechthold, Pablo Ignacio; Jasen, Paula Verónica; Gonzalez, Estela Andrea; Juan, Alfredo In this work, Density Functional Theory (DFT) is used to study pristine and defectiveGDY. We investigate the effect of Li atom adsorption on the electronic and structuralproperties of this 2D material. In both cases, the Li atom is located at the corner of thetriangular-like pore (H1), but with a slight shift for the defective system. In the perfectsystem, the Li-C bond distances range from 2.289 Å to 2.461 Å, while in the defectivecase, they range from 2.237 Å to 3.184 Å. In the perfect case, the GDY-Li systembecomes metallic and the Li 2s states are stabilized. Charge transfer to the surfacesoccurs near the vicinity of the Li atom. The C vacancy generates new C=C bonds similarto double bonds, enhancing the interaction with Li through strong conjugation. After Liadsorption, the sum of bond order for all the C atoms increases in both structures,from 0.4% to 6%. The Li storage capacity without significant restructuring is six Liatoms. When the atom concentration increases, the OCV values for Li decrease from 0.93 V to 0.23 V. For defective GDY, the specific capacity is 788 mAhg-1, which isslightly higher than for pristine case.

Fotografiar el ambiente: Aportes de una experiencia con niños/as y adolescentes en el barrio

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Fotografiar el ambiente: Aportes de una experiencia con niños/as y adolescentes en el barrio; Photograph the environment: Contributions from an experience with children and adolescents in the neighborhood; Fotografar o ambiente: Contribuições de uma experiência com crianças e adolescentes do bairro Pi Puig, Ana Pilar; Guzzo, María del Rosario; Guevara, Bárbara El presente artículo parte del relato de una experiencia de trabajo en el marco del proyecto de extensión “Educación y Promoción de derechos en el barrio José Luis Cabezas de Ensenada” (FaHCE-UNLP). Esta consistió en un taller de fotografía centrado en la temática del ambiente, a través del cual se desarrollaron diferentes actividades con niños/as y adolescentes del barrio. Desde allí, el artículo busca poner de relieve dos dimensiones que atraviesan el quehacer extensionista en nuestro equipo. Por un lado, una estrategia metodológica que parte de recuperar y poner en valor los saberes y las prácticas de los/as niños/as y adolescentes. Por otro lado, una perspectiva “desde abajo” que, en tanto parte del territorio, adquiere pleno sentido en y para sus habitantes. Se concluye que el taller, orientado por la promoción del acceso a derechos, afianzó la concepción del ambiente como amalgama entre lo natural y lo construido.; This article is based on the story of a work experience within the framework of the extension project "Education and Promotion of Rights in the José Luis Cabezas neighborhood of Ensenada" (FaHCE- UNLP). It consisted of a photography workshop focused on the environment, through which different activities were developed with children and adolescents from the neighborhood. From there, the article seeks to highlight two dimensions that cross the extension work in our team. On the one hand, a methodological strategy that starts from recovering and valuing the knowledge and practices of children and adolescents. On the other hand, a perspective "from below”, that, as part of the territory, takes on full meaning in and for its inhabitants. It is concluded that the workshop, oriented by the promotion of access to rights, it strengthened the conception of the environment as an amalgam between the natural and the built.; Este artigo parte de uma experiência de trabalho no âmbito do projeto de extensão "Educação e Promoção dos Direitos no Bairro José Luis Cabezas de Ensenada" (FaHCE-UNLP). Este consistiu numa oficina de fotografia focada na temática do meio ambiente, por meio da qual foram desenvolvidas diversas atividades com crianças e adolescentes do bairro. A partir daí, o artigo busca destacar duas dimensões que atravessam o trabalho de extensão da nossa equipe. Por um lado, uma estratégia metodológica baseada na recuperação e valorização dos saberes e práticas das crianças e adolescentes. Por outro lado, uma perspectiva “de baixo” que, como parte do território, adquire pleno significado em e para seus habitantes. Concluise que a oficina, orientada por a promoção do acesso aos direitos, fortaleceu a concepção do meio ambiente como um amálgama entre o natural e o construído.

Deployment and performance of a Low-Energy-Threshold Skipper-CCD inside a nuclear reactor

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Deployment and performance of a Low-Energy-Threshold Skipper-CCD inside a nuclear reactor Depaoli, Eliana Leticia; Rodrigues Ferreira Maltez, Dario Pablo; Sidelnik, Iván Pedro; Bellino, P.; Botti, A.; Delgado, D.; Cababie, Mariano Ruben; Chierchie, Fernando; Estrada, Juan; Fernández Moroni, Guillermo; Perez, S.; Tiffenberg, J. Abstract: Charge Coupled Devices (CCD) are being used for reactor neutrino experiments and have already demonstrated their potential in constraining new physics models. The prospect of a Skipper-CCD experiment looking for standard and beyond standard model (BSM) physics in a nuclear reactor has been evaluated for different benchmark scenarios. Here, we report the first installation of a 2-g Skipper-CCD inside the containment building of a 2GWth nuclear power plant and analyze its performance throughout its first 18 months of operation. The sensor was successfully deployed at Atucha II, in Argentina, 12 meters away from the center of the reactor core. We discuss the challenges involved in the commissioning of the detector and present data acquired during reactor ON and reactor OFF periods, with the sensor functioning with a sub-electron readout noise of 0.17 e−. Based on an exposure of 56.8 g day reactor ON and two reactor OFF data sets with a total exposure of 118.1 g day we characterize the system and evaluate the sensitivity to CEvNS. We achieved a background rate of 33 kdru and a low threshold of 45 eVee. The ongoing efforts to improve sensitivities to CEvNS and BSM interaction are also discussed.

Agroecological Aptitude of the Northeast of Formosa (Argentinean Subtropical Region) for Banana Production Assessed by Multiple Factor Analysis

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Agroecological Aptitude of the Northeast of Formosa (Argentinean Subtropical Region) for Banana Production Assessed by Multiple Factor Analysis del Médico, Ana Paula; Vitelleschi, María Susana; Lavalle, Andrea Lina; Tenaglia, Gerardo Carlos; Pratta, Guillermo Raúl Banana (Musa spp.) is an important crop in the economies of many developing countries. In the north of Argentina, a subtropical region, banana plants grow in a suboptimal environment that limits yield because only one harvest per year is achieved. The objective of this work was to characterize the agroecological aptitude of Formosa, Argentina, for banana production through the behavior of three varieties of international use: Williams, Jaffa and Grand Naine, evaluated over five consecutive years. The three-way data analysis technique called Multiple Factor Analysis (MFA) was used for evaluating the varieties’ performances across cycles of production. The results allowed for inferring the existence of a genotype x environment interaction (GEI), corroborated by two-way factorial ANOVA. In order to determine how this suboptimal environment affected the development of each genotype of this perennial crop, Dual Multiple Factor Analysis (DMFA) was applied to jointly analyze the correlation structure between the traits that contributed to the performance of each variety in each year. The correlation structures between variables were different in each population and varied between years. All traits showed great variation between the years and genotypes, with the fruit peel thickness being the most discrepant throughout the years. However, Formosa appeared as a promising subtropical agroecological environment to produce banana because the varieties’ performances were acceptable for large-scale production systems. In addition to evaluating the adequate aptitude for cultivating banana in Formosa considering the significant effect of the GEIs, this research made a methodological contribution by proposing the use of three-way data analysis in Agronomy Science via MFA and DMFA.

An ultra-low noise fully-differential amplifier

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An ultra-low noise fully-differential amplifier Spinelli, Enrique Mario; Haberman, Marcelo Alejandro A general-purpose instrumentation amplifier must be dc-coupled and has a differential input to handle both differential and single-ended input signals. It must also exhibit low input noise in both voltage and current to accommodate a wide range of signal source impedances. Additionally, having a differential output is desirable to allow direct connection to current high-resolution analog-to-digital converters (ADCs), which have differential inputs. There are commercially available devices with en voltage noise spectral densities as low as 1 nV/Hz−−−√ but present high current noise spectral densities in of a few pA/Hz−−−√ . On the other hand, there are also devices with in as low as a few fA/Hz−−−√ but presenting en around 10 nV/Hz−−−√ . To obtain low values of both en and in , a fully differential circuit topology combining discrete junction field transistors (JFETs) and operational amplifiers (OAs) is proposed. Design equations, stability analysis, and experimental results are presented. As an example, a fully differential instrumentation amplifier has been designed, built, and tested showing en<1 nV/Hz−−−√ at 1 kHz and in<10 fA/Hz−−−√ at 1 kHz. The proposed topology finds applications, such as front ends for measuring and testing instruments, industrial instrumentation, and audio circuits.

Neotectonics of the Magallanes-Fagnano fault system in Fuegian Patagonia based on high-resolution seismic profiles and geomorphic markers

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Neotectonics of the Magallanes-Fagnano fault system in Fuegian Patagonia based on high-resolution seismic profiles and geomorphic markers Restelli, Florencia Belen; Bran, Donaldo Mauricio; Almaraz, Fernando; Menichetti, M.; Lodolo, E.; Esteban, Federico Damián; Lozano, Jorge Gabriel; Tassone, Alejandro Alberto The Magallanes–Fagnano Fault System (MFFS), located at the southern tip of Patagonia, is part of the transform plate boundary between the Scotia and South American plates. Modern deformation along the fault system has been mostly studied on land, such as in the eastern region of Lago Fagnano. Furthermore, previous studies have primarily focused on the analysis of co-seismic deformation, while the long-term landscape response to neotectonics has not been addressed in detail. This work aims to identify and characterize active fault segments within the lake sediments and investigate the imprint of deformation in the surrounding landscape. To achieve this, we integrate high-resolution seismic profiles acquired in Lago Fagnano with a morphometric analysis of the hydrographic basin. These segments show subaqueous ruptures affecting the lacustrine sediments reaching the lake floor, indicating recent deformation episodes. Most of the recognized faults are sub-vertical or dip steeply (> 60°) to the south and show vertical offsets that range from 4 to 17 m. The morphometric analysis is consistent with the overall southward dip of the MFFS and indicates a hydrographic rejuvenation towards the north of the lake. In addition, the ruptures of the fault system can be correlated with the deformation observed on land, resulting in a ~ 150 km long segmented surface rupture zone that might be consistent with the rupture length estimated for the 1949 M7.5 earthquake doublet.

Comprender a Spinoza desde la intimidad de la lengua: Nota al margen de una nueva edición de la Ética

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Comprender a Spinoza desde la intimidad de la lengua: Nota al margen de una nueva edición de la Ética Tatián, Diego La más reciente traducción de la Ética demostrada según el orden geométrico, realizada por Mario Caimi para la impresionante colección de clásicos de la editorial Colihue, constituye un acontecimiento para la filosofía en nuestra lengua y una enorme contribución para la comprensión de este libro singular. Se trata de una edición anotada, que cuenta con un extenso estudio preliminar donde su autor -a la manera de los trabajos clásicos de Martial Gueroult y Pierre Macherey en francés, o de Filippo Mignini en italiano- analiza minuciosamente el recorrido de proposiciones de cada una de las cinco partes de la obra.La tesis fundamental en la interpretación del libro mayor de Spinoza que desarrolla ese estudio -de ahora en más, un precioso instrumento de trabajo para investigadores a la vez que una introducción a la filosofía spinozista para quienes deseen iniciarse en ella-, consiste en que la Ética no es esencialmente un libro de ética sino de metafísica: una teoría de “lo que verdaderamente es”. El nombre de la obra habría sido adjudicado por los editores de las Opera posthuma y no por Spinoza mismo (quien en sus cartas, efectivamente, alude a ella como “mi filosofía”, pero nunca con el título bajo la que fue editada en 1677 apenas después de su muerte). En contraposición a un extendido arco de lecturas que incluye estudiosos tan diversos como Jonathan Bennett y Gilles Deleuze, el profesor Mario Caimi sostiene que el objetivo principal de este libro no es la búsqueda de la felicidad (Beatitudo) o la vida buena, sino la comprensión del fundamento y el ser de las cosas bajo el “aspecto de la eternidad”.

Hydrogeomorphological changes and the erosion-deposition impact in the San Francisco River Basin, Northwest Argentina: a multidecadal analysis

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Hydrogeomorphological changes and the erosion-deposition impact in the San Francisco River Basin, Northwest Argentina: a multidecadal analysis Isuani, María Antonella; Georgieff, Sergio Miguel; Bustos, María Soledad Modifications of wetland and forest areas are studied, in particular, to establish to what extent they are sensitive to natural changes (e.g., increased precipitation and/or temperature) in addition to human activities (e.g., advancing agricultural frontier, deforestation, channelizations). The San Francisco River Basin (SFRB; 1,789 km2) is located in the Northwest of Argentina in the Geological Province of Nortwestern Pampean Ranges (Sierras Pampeanas Noroccidentales), between 27°40?S and 28°25?S, and 65°15?W and 65°45?W). In recent decades, agricultural development and management in the middle and lower SFRB generated rural channelizations (the largest of 10 km at the basin outlet between 2005-2015), drainage of wetland forests, deforestation of native dry forest since 1995 and changes in land use. In addition, a 200 mm increase in mean annual rainfall since 1972 and an increase in extreme hydrological events, are registered. These modifications produced changes in local base level, erosive processes of retreat and the development of new river channels from upstream, increasing flow velocities, flow rates, and sediment discharge. The intensified erosive processes resulted in four new river courses in the middle and lower basin, incorporating the SFRB into the Marapa river basin, changing from arheic to endorheic behaviour, and generating the contribution of liquid and solid flows to the system of which it is now a part. The aim of this study is to examine the development of the new hydrographic network within the SFRB between 1990 and 2018 and to calculate the solid and liquid discharges generated by the new network. The hydrographic network formed by the rivers El Abra, Ovanta, San Francisco and Suncho creek, was digitized in the open-source software QGIS 3.18.3 on the basis of the visual interpretation of satellite imagery. The lengths of the rivers were automatically calculated and exported to a spreadsheet to determine the downstream expansion of the river network. Measurements and sampling of water discharge and sediment load were performed monthly in the lower section of the SFRB. The float and crosssection method was used to quantify the flow rates, and the sediment samples were filtered, dried in an oven for 24 h and weighed on a precision balance to obtain the sediment concentration (C in mg/l). The study determined the generation of 102 km of new river channels in a 28 yr period. The hydrographic network had an annual sediment production of 82,138 t/yr and an annual discharge of 21,96 hm3, contributing to the Marapa river basin and generating an acceleration in the silting of the downstream Río Hondo reservoir. This work provides a basis for management and mitigation of erosion and flooding problems in the area.

El movimiento nutricionista internacional como libreto y su adopción en América Latina: las encuestas alimentarias en la década de 1930

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El movimiento nutricionista internacional como libreto y su adopción en América Latina: las encuestas alimentarias en la década de 1930; O movimento internacional de nutrição como guia e sua implementação na América Latina: pesquisas de alimentação nos anos 1930; The international nutrition movement as a guide and its adoption in Latin America: food surveys in the 1930s Buschini, Jose Daniel Este artículo analiza una serie de encuestas alimentarias que tuvieron lugar en América Latina durante la década de 1930. Se argumenta que la realización de estas encuestas formó parte de un proceso más amplio, consistente en la participación de la región en la consolidación y expansión del movimiento nutricionista internacional, que entonces despuntaba. El trabajo hace foco en tres aspectos de esas encuestas, para mostrar de ese modo la conexión entre los desarrollos locales y globales.; Este artigo analisa uma série de pesquisas sobre alimentação realizadas na América Latina durante a década de 1930. Argumenta-se que a realização dessas pesquisas integra um processo mais amplo de participação da região na consolidação e expansão do então emergente movimento internacional de nutrição. O artigo se concentra em três aspectos dessas pesquisas para mostrar a relação entre o desenvolvimento local e global.; This study analyzes a series of food surveys that took place in Latin America during the 1930s. It argues these surveys belonged to a broader process consisting of the region participating in the consolidation and expansion of the then emerging international nutrition movement. This study focuses on three aspects of these surveys to show the connection between local and global developments.

Design of the tertiary optical system for the Large Latin American Millimeter Array radio telescope

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Design of the tertiary optical system for the Large Latin American Millimeter Array radio telescope Rasztocky, Emiliano; Hampel, Matias Rolf; Reeves, Rodrigo; Lepine, Jacques R.D.; Romero, Gustavo Esteban Many modern radio telescopes employ an observational strategy that involves maximizing the use of their available spaces (cabins), outfitting them with various receivers at different frequencies to detect incoming signals from the sky simultaneously or individually. The Large Latin American Millimeter Array is a joint venture between Argentina and Brazil consisting of the installation and operation of a 12-m aperture Cassegrain telescope. It features three available cabins for instrumentation and plans to install six single-pixel heterodyne receivers, covering different bandwidths in the 30 to 950 GHz window of the electromagnetic spectrum, in its two lateral Nasmyth cabins at different phases of the project. Therefore, it is crucial not only to design a tertiary optical system that couples the antenna beam to those receivers but also to do it in a scalable way. The primary goal for the design is to simultaneously maximize the antenna efficiency while minimizing optical aberrations for all receivers, both fundamental aspects for the optimal functioning of cutting-edge astronomical instruments. We present the entire design process, starting from the quasi-optical approach based on the propagation of a fundamental Gaussian beam mode, continuing with the validation of the design based on physical optics simulations, and ending with a tolerance analysis of the system. As a result of this process, a frequency-independent tertiary optical system has been achieved for almost all the receivers, which is expected to provide high optical performance for the radio telescope.

A supervised data-driven spatial filter denoising method for speech artifacts in intracranial electrophysiological recordings

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A supervised data-driven spatial filter denoising method for speech artifacts in intracranial electrophysiological recordings Peterson, Victoria; Vissani, Matteo; Luo, Shiyu; Rabbani, Qinwan; Crone, Nathan E.; Bush, Alan; Richardson, R. Mark Neurosurgical procedures that enable direct brain recordings in awake patients offer unique opportunities to explore the neurophysiology of human speech. The scarcity of these opportunities and the altruism of participating patients compel us to apply the highest rigor to signal analysis. Intracranial electroencephalography (iEEG) signals recorded during overt speech can contain a speech artifact that tracks the fundamental frequency (F0) of the participant’s voice, involving the same high-gamma frequencies that are modulated during speech production and perception. To address this artifact, we developed a spatial-filtering approach to identify and remove acoustic-induced contaminations of the recorded signal. We found that traditional reference schemes jeopardized signal quality, whereas our data-driven method denoised the recordings while preserving underlying neural activity.

Selected farm-level crop protection practices in Europe and Argentina: Opportunities for moving toward sustainable use of pesticides

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Selected farm-level crop protection practices in Europe and Argentina: Opportunities for moving toward sustainable use of pesticides Mark, Jennifer; Fantke, Peter; Soheilifard, Farshad; Alcon, Francisco; Contreras, Josefa; Abrantes, Nelson; Campos, Isabel; Baldi, Isabelle; Bureau, Mathilde; Alaoui, Abdallah; Christ, Florian; Mandrioli, Daniele; Sgargi, Daria; Pasković, Igor; Pasković, Marija Polić; Glavan, Matjaz; Hofman, Jakub; Harkes, Paula; Lwanga, Esperanza Huerta; Norgaard, Trine; Aparicio, Virginia Carolina; Schlünssen, Vivi; Vested, Anne; Silva, Vera; Geissen, Violette; Tamm, Lucius Extensive use of plant protection products (PPP) in the last decades contributes to negative impacts on ecosystems, animals and humans. For the strategies of PPP reduction and replacement of hazardous pesticides, farm-level data on agronomic management practices and crop protection applications are crucial. In this study, we strategically collected data for the 2021 season at the SPRINT project case study sites (CSS) in 10 European countries and Argentina, on perennial, arable and vegetable crops. Data collection included strategically selected farm and field data, pesticide records and farming practices. Results involved more than 1700 recorded PPP applications across various crops with more than 170 different active substances from PPP in organic, integrated pest management and conventional farming practices. We explored differences in application patterns (fungicides, insecticides, herbicides and non-PPP, e.g. adjuvants, growth regulators, and fertilizers) between and within crops, countries and farming systems and calculated the costs of PPP use. The pesticide dosages applied during the crop season varied up to a factor of 20 around recommended doses. Regarding the costs of PPPs use perennial crops had the highest costs per ha crop production area. Finally, we analysed the active substances applied in different farming systems in terms of their hazard statements. Our results shed light on how PPPs are used across different crop and farming types and will help elucidate how pesticide application patterns can be changed in the future. Finally, we highlighted non-PPP use practices which help to reduce dependency on PPP use. This might be used to support decision-making and policies within agricultural advisory/support systems.

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