National Space Activities Commission

The Circinus galaxy is the nearest type-2 Seyfert galaxy, located at a distance of 4.2 Mpc. Its environment is challenging to explore because of the low Galactic latitudes of its location, behind the disc of the Milky Way. The long-term goal of this work is to characterise the Circinus galaxy halo. We are also interested in determining the possible presence of dwarf satellites using near-infrared (NIR) data. We selected 1,542 galaxies from the VISTA Variables in the Vía Láctea (VVV) NIR galaxy catalogue within a 2-degree radius around the Circinus galaxy, representing roughly 2/3 of the virial radius. We used structural parameters, such as the half-light radii and colours, and correlations were examined. A neural network was trained with 486 galaxies with known spectroscopic redshifts to estimate photometric redshifts for all of these galaxies. The potential satellites of the Circinus galaxy were defined on the basis of half-light radii that were compatible with the typical sizes of dwarf satellites in galaxies and combined with photometric redshifts. The galaxy properties have been reliably characterised down to K_ s ∼ 15.5 mag, representing about 90% completeness of the detections. At the distance of the Circinus galaxy, this limiting magnitude corresponds to a K_s absolute magnitude of -12.6 mag, allowing us to locate dwarf galaxies. In total, there are 20 galaxies with half-light radii larger than 2.45 arcsec, but only 8 of them have photometric redshifts below 0.04. None of these galaxies are close to the Circinus galaxy, which has a redshift of 0.0015 and shows no evidence of associated clustering. The ANNz model exhibited a high degree of accuracy in the range of $0.001 < z_ phot < 0.023$, thereby validating this method in these extinct regions. The presence of dwarf satellites associated with the Circinus galaxy could not be confirmed with the available data in the studied region. The apparent lack of satellites could be genuine, possibly related to AGN feedback effects. Nevertheless, this work demonstrates the effectiveness of combining near-infrared data and machine learning techniques to estimate photometric redshifts at low Galactic latitudes, thereby providing useful information for future spectroscopic follow-up campaigns.

Empowerment can be thought of as a gain of power and autonomy by an unfavored group, which creates a better situation. Women in Science (WIS) face multiple barriers that ultimately affect their performance. There is an urgent need to reverse the inequalities and disadvantages that WIS face. With this aim, in May 2023, 17 WIS gathered in person for four days in a workshop entitled Empowering Women in Science. As an outcome of the workshop, we cooperatively started to draw up a list of empowerment recommendations. We continued working together for more than a year to improve this list, which we now present as the Good Practice Guide for Empowering Women in Science (GPG). The GPG contains recommendations across the individual, collective and system levels that we believe help address inequalities for WIS. The aim of this debate is twofold: a) to present the GPG and b) to use the GPG to self-evaluate the number of actions we, the authors, undertook before and after participating in the workshop. Results show that one year after ending the workshop, we doubled the number of actions performed across all categories assessed: I) identify, confront and make visible systemic barriers; II) self-promotion; III) promote other women, and IV) foster diversity, equity and inclusion. This suggests that empowerment can be fostered through formal training programs and discussion spaces. We hope that the GPG will inspire WIS across disciplines and backgrounds to: A) act towards empowerment (at the individual, collective and system level); B) embrace the notion that each of us can be part of the change that we want to see happening towards higher equity for WIS, and C) recognize that any action is better than inaction. Finally, the GPG provides a framework that will continue to be improved and expanded with the feedback of readers and users.

El presente artículo explora la organización de la tecnología lítica del sitio Cerro Casa de Piedra 7 (CCP7), ubicado en el área lacustre-cordillerana del noroeste de Santa Cruz, Argentina. CCP7 posee una secuencia cronológica amplia que evidencia la incorporación de la tecnología de hojas líticas a partir de ca. 7800 cal AP. Esto no es algo aislado, ya que a nivel regional esta nueva tecnología comienza a hacerse visible a partir del Holoceno medio, conformando una alternativa con respecto a la tecnología de lascas. En este estudio se compararon los artefactos elaborados sobre hoja con aquellos manufacturados sobre otros tipos de soporte. De este modo, se buscó evaluar la variabilidad interna del conjunto, identificar patrones de manufactura y se propusieron posibles usos relacionados al subconjunto de hojas. Los resultados indican cierto grado de estandarización de las piezas, un aprovechamiento eficiente de sus bordes, una selección cuidadosa de materias primas y diseños especializados para realizar tareas específicas. Todo esto sugiere que la adopción de esta nueva tecnología no respondió tanto a una maximización de los recursos líticos, sino más bien a una búsqueda de optimizar la eficiencia y versatilidad de estos útiles. Así, este trabajo aporta nueva información sobre la introducción y desarrollo de la tecnología de hojas en Patagonia centro-meridional e invita a pensar qué motivó su incorporación y/o adopción por parte de los grupos cazadores-recolectores que habitaron la región a partir del Holoceno medio.

Sarcoptic mange, caused by the mite Sarcoptes scabiei, is a highly contagious and potentially fatal skin disease that affects a wide range of mammals, including South American Camelids (SAC). Although the presence of mange has been described in vicuñas and llamas in northwestern Argentina, there are no previous records documenting its presence in guanacos (Lama guanicoe) of this region. We here describe a case of S. scabiei in a free-ranging guanaco in the Department of Tilcara, Jujuy Province. The animal presented alopecic, erythematous and hyperkeratotic lesions with abundant crusts in the ventral region of the body and limbs. Histopathology revealed periadnexal dermatitis with inflammatory infiltrate, severe hyperemia, orthokeratotic and parakeratotic epidermal hyperplasia, and stratum corneum thickening. The etiological agent was identified as S. scabiei by microscopic examination of adult mites. This result was confirmed by sequencing of a cytochrome oxidase subunit I gene fragment, that showed 100% identity with sequences of isolates from SAC and other mammals. Genotyping of three mites isolated from different parts of the guanaco's body using a set of ten microsatellite markers indicated the infection with a single genetic variant that showed a similar profile to those found in S. scabiei isolates from vicuñas and llamas of the same region. However, genetic differences with guanaco isolates from midwestern Argentina were observed. This work presents the first record of sarcoptic mange in a guanaco in Jujuy Province and in the northwestern region of Argentina, as well as the molecular characterization of the etiological agent. The case highlights an uncertain scenario regarding the health situation of the guanaco population in this region, which is small, fragmented, and locally categorized as endangered. Epidemiological surveillance programs for guanacos and further research on the impact of sarcoptic mange on the conservation of this species are needed.

ABSTRACTThe South American Gran Chaco is among the most threatened ecoregions worldwide. Although land use change in the plains of this region has been widely studied, less is known about the southern mountainous areas. Our main goal was to analyze the land cover change dynamics in the Chaco Serrano between 1989 and 2019. We developed 3 land cover maps for the Sierras Chicas of central Argentina (1989, 2004 and 2019) and performed a land cover change analysis. Serrano forests lost 67,055 ± 8127 ha, and the annual rate of deforestation increased from −0.58 (1989–2004) to −1.87 (2004–2019). Between 1989 and 2019, grasslands exhibited the second‐highest negative annual rate of change (−0.59). In 2019, shrublands became the dominant cover, increasing their size by 30% compared to 1989. Urban areas had the highest positive annual rate of change (5.60) and increased their extension from 1% of the total study area in 1989 to 5% in 2019. Invasive alien species expanded rapidly but only in specific areas. Our main findings show that land cover change processes in the Chaco Serrano mountains have differed from those observed in the plain areas of the Chaco and were consistent with those observed in other mountainous regions of the world. The current scenario for the Serrano forest is critical, and if conservation strategies are not applied in the near future, it could be expected that most of the Serrano forest, a unique ecosystem within the Chaco, would eventually disappear.

This letter describes a procedure based on the radiative transfer theory to calibrate the scattering contributions from the Generalized Freeman-Durden (GFD) polarimetric decomposition over corn fields. The Tor Vergata electromagnetic model (TOV) is used to simulate canonical scattering mechanisms that are compared with those obtained applying GFD to both simulated and L-band SAOCOM-1A data. The proposed method first analyzes the error between the model and the GFD applied to the simulated data. A multivariate data fitting is then performed to derive a new expression of the GFD powers, which is tested on L-band real data. The GFD volume power obtains the greatest benefit from the calibration, reducing the Root Mean Square Error (RMSE) with respect to the corresponding TOV model contribution to 0.006 in linear units. To further test the procedure, a linear regression model is used to estimate soil moisture using the calibrated GFD powers from SAOCOM-1A real data. The retrieval performance, evaluated through a Leave-One-Out (LOO) cross-validation against in situ data, shows a significant improvement: the calibrated GFD powers leads to an increased linear correlation (0.32 to 0.57), while the RMSE is reduced (0.096 to 0.055 m³/m³).

Introducción: Las características del entorno alimentario condicionan la elección de alimentos. Objetivo: Diseñar e implementar una metodología para explorar las características del entorno alimentario en un barrio céntrico de la ciudad de Córdoba, Argentina, a partir de la disponibilidad de comercios y tiendas de alimentos acorde con las recomendaciones de la dieta DASH (Dietary Approaches to Stop Hypertension). Materiales y métodos: Se relevaron 223 comercios para determinar el tipo de establecimiento y la disponibilidad de alimentos en base a los enfoques mencionados y se georeferenciaron en base a coordenadas extraídas de la plataforma Google Earth. Se clasificaron los comercios construyendo una variable cuantitativa continua que resume la información sobre las ventas de productos en cada lugar (DASH Score). El mapeo temático y la construcción del Score se realizaron con el software Qgis 3.22. Resultados: Se observó un alto predominio de quioscos, panaderías y locales de comida rápida (59,5 %) y los comercios que venden sólo alimentos frescos representaron el 17,4 % del total. Los establecimientos considerados no saludables se ubicaron al norte del barrio. Conclusiones: El enfoque propuesto contribuye al estudio de entornos alimentarios como una herramienta para la prevención de enfermedades no transmisibles y la promoción de la salud.

Chromophoric dissolved organic matter (CDOM) is crucial in aquatic ecosystems, influencing light penetration and biogeochemical processes. This study investigates the CDOM variability in seven oligotrophic lakes of North Andean Patagonia using Landsat 8 imagery. An empirical band ratio model was calibrated and validated for the estimation of CDOM concentrations in surface lake water as the absorption coefficient at 440 nm (acdom440, m−1). Of the five atmospheric corrections evaluated, the QUAC (Quick Atmospheric Correction) method demonstrated the highest accuracy for the remote estimation of CDOM. The application of separate models for deep and shallow lakes yielded superior results compared to a combined model, with R2 values of 0.76 and 0.82 and mean absolute percentage errors (MAPEs) of 14% and 22% for deep and shallow lakes, respectively. The spatio-temporal variability of CDOM was characterized over a five-year period using satellite-derived acdom440 values. CDOM concentrations varied widely, with very low values in deep lakes and moderate values in shallow lakes. Additionally, significant seasonal fluctuations were evident. Lower CDOM concentrations were observed during the summer to early autumn period, while higher concentrations were observed in the winter to spring period. A gradient boosting regression tree analysis revealed that inter-lake differences were primarily influenced by the lake perimeter to lake area ratio, mean lake depth, and watershed area to lake volume ratio. However, seasonal CDOM variation was largely influenced by Lake Nahuel Huapi water storage (a proxy for water level variability at a regional scale), followed by precipitation, air temperature, and wind. This research presents a robust method for estimating low to moderate CDOM concentrations, improving environmental monitoring of North Andean Patagonian Lake ecosystems. The results deepen the understanding of CDOM dynamics in low-impact lakes and its main environmental drivers, enhance the ability to estimate lacustrine carbon stocks on a regional scale, and help to predict the effects of climate change on this important variable.

This work presents the calibration/validation results of the operational classification product of SAOCOM mission, integrating a year's worth of field campaigns during the period 2019-2020 in a central area of the Argentine Pampas region with accuracies varying between 62% and 90% depending on the crop and its phenological phase. Accurate crop classification is a necessary preliminary step for soil moisture estimation in the SAOCOM mission (L-band Synthetic Aperture Radar satellite). For this purpose, reaction-diffusion systems that employ stochastic distances were used to reduce noise in SAR (Synthetic Aperture Radar) images and classify them.

Human activities like agriculture, industrialization, urbanization, and population growth have increased nutrient inputs in aquatic ecosystems, disrupting natural nutrient cycles. This study helps to understand how nutrients move in a river basin using the InVEST NDR module in order to model and map total nitrogen and total phosphorus delivery from different land use and land cover (LULC). Identifying non-point pollution sources and evaluating nutrient retention by vegetation allow us to understand how LULC can affect the quality of water in the Suquía River basin by affecting the amount of nutrients that get carried away in the water.