Instituto de Física del Litoral

Abstract Anthropogenic activities such as agriculture and keeping livestock have significantly modified natural ecosystems, transforming them into agroecosystems and contributing to habitat loss and species decline. In Argentina, agricultural expansion has been accompanied by increased use of agrochemicals, raising concerns about their impact on biodiversity. These chemicals can affect organisms directly during application or persist in the environment, potentially disrupting reproduction. Our study focuses on Caiman latirostris populations, a species whose distribution overlaps with croplands. We conducted a comprehensive long‐term spatial and multitemporal analysis of some reproductive parameters in C. latirostris in 2000–2018, using six nesting areas located in central‐northern Santa Fe, Argentina. This analysis integrated geospatial tools to assess the impact of agrochemical exposure on reproduction. Nest monitoring data from the Proyecto Yacaré conservation program were integrated with geospatial datasets through the Google Earth Engine (GEE) platform, utilizing AI tools to evaluate environmental disturbances of each nesting area and its perinesting environment. This assessment incorporated web feature geoservices (WFS), vegetation indices (NDVI) temporal series, and land use/land cover. Reproductive parameters, including hatching success, the percentage of non‐viable embryos, infertile eggs, and neonate malformations, were analyzed in relation to the proximity of agricultural activities. Results revealed a significant decline in hatching success, accompanied by an increase in the proportion of non‐viable embryos and infertile eggs in the nests, particularly in nesting areas associated with agricultural activities. The integration of geotechnologies provided a comprehensive evaluation of the spatial and temporal aspects of the impacts of agricultural expansion on C. latirostris reproduction. These findings suggest that chronic exposure to agrochemicals is a plausible factor contributing to the decline in reproductive success, with broader implications for conservation in agroecosystems. This study highlights the utility of geotechnologies in monitoring environmental changes and their effects on wildlife. Our results also offer a scalable approach to assess anthropogenic impacts on other species and ecosystems, providing critical insights for conservation strategies.

Exposure to poly- and perfluoroalkyl substances (PFASs) has been a cause for concern for decades due to evidence linking exposure to these substances with adverse health effects. Its widespread use in industrial and consumer products combined with their persistence in the environment poses a toxicological and regulatory challenge. Due to its ubiquity, resistance to degradation, and accumulation in biological systems, humans are exposed to a mixture of multiple PFASs, which complicates the analysis of exposure effects. As PFASs pose a risk to human health, it is crucial to study their impact during vulnerable periods, such as pregnancy. In this regard, understanding the impact of PFASs on the placenta is essential, as they can affect both pregnancy and the well-being of the developing fetus. This article reviews the current evidence linking PFAS exposure with altered placental function, focusing on the affected molecular pathways. Furthermore, we examine current methodologies for analyzing the effects of exposure to complex mixtures and explore how these approaches could be employed to evaluate the potential impact of such mixtures on placental function in the context of real-life exposure to these chemicals.

In this study, the structure of metazoan endoparasites infracommunities and component community in Erythrolamprus poecilogyrus caesius (Cope, 1862) (Serpentes: Dipsadidae) is presented. From 21 specimens (15 females; 6 males) collected between February 2017 and March 2022 at Ingeniero Juárez, Formosa, Argentina, 90.5% of individuals surveyed (n= 19) were infected with at least one species of metazoan endoparasite. Nine hundred sixty specimens were collected (117 adults; 843 larvae), from 11 taxa. Kalicephalus appendiculatus (Nematoda), Raillietiella furcocerca (Pentastomida), Ophiotaenia joanae, Catadiscus uruguayensis, Opisthogonimus lecithonotus (Platyhelminthes) were found as adults. Larvae identified were Oligacanthorhynchus sp. (Acanthocephala), Physaloptera sp. (Nematoda), Strigea spp. and Alaria sp. (Digenea). Digenea was the richest group (S= 6). Adults were collected in intestines, trachea and esophagus, while larvae were found in mesenteries and body cavity. Ophiotaenia joanae was the most prevalent species (38.1%) and K. appendiculatus had the highest mean abundance (3.7). Considering larvae, Strigea spp. were dominant and Oligacanthorhynchus sp. was subdominant. Between pairs of metazoans, positive and negative covariations were obtained. In general, intensity of metazoan taxa had positive correlation to host weight and body condition but had negative relationships with snout-vent length. Mean infracommunity richness (including larvae and adults) was 4.35 ± 1.27 taxa/host. Richness and diversity were higher in larval infracommunities than those composed by adults. This is the first ecological study of endoparasites in snakes from Argentina. New reports to parasite biodiversity in Dry Chaco were added, also, information about habitat use, diet, and position in trophic webs of host was generated.

We investigate the drying dynamics of mesoporous silicon bilayers with controlled pore geometries during ethanol evaporation. Using Reflective Interferometric Fourier Transform Spectroscopy (RIFTS), we track the evolution of liquid saturation in each layer. We find that placing smaller pores atop larger ones─mimicking an ink-bottle geometry─can unexpectedly accelerate evaporation under specific thickness ratios. This behavior suggests a complex interplay of mass transport mechanisms beyond simple geometrical constraints. Additionally, we introduce a novel image-based method for spatially resolved saturation mapping over millimeter-scale areas, complementing the localized RIFTS measurements. Our results demonstrate that evaporation dynamics in porous films can be modulated through structural design, providing new experimental tools to study and tailor fluid transport in hierarchical porous materials.

La variabilidad de la irradiancia solar introduce limitaciones a la producción de energía solar fotovoltaica(PV) ya que dificulta su despacho. Por lo tanto, su cuantificación es importante para el desarrollo en gran escala desistemas PV y su contribución relativa a la matriz eléctrica. Argentina posee un gran potencial para la generación solar,con un extenso territorio que recibe una irradiación promedio anual de 5 kWh/m2/día. Además, cuenta con el respaldode políticas públicas y regulaciones que fomentan la transición hacia fuentes de energía renovable. En este trabajo secuantificó la variabilidad de corto plazo (minutal, 10-minutal y horaria) mediante la desviación estándar de los cambiosen el índice de cielo claro (kc). Se analizaron las series temporales de los años 2019 y 2020 en 6 estaciones de la redArgentina de radiación solar Saver-Net. Se encontró un promedio de variabilidad nominal en los sitios de 0,09, 0,13 y0,15 para 1 minuto, 10 minutos y 1 hora, respectivamente. Estos valores sugieren una variabilidad intermedia del recursosolar a lo largo del territorio.Palabras clave: Fluctuaciones, GHI, Energía solar

This study evaluated the effects of supplementing early-lactation Holstein cows with rumen-protected omega-3 fatty acids (calcium salts) on productive and reproductive performance. Thirty-six multiparous cows were randomly assigned to one of two treatments from 21 ± 2 days before calving to 105 ± 5 days in milk (DIM): a Control group (C) or an Omega-3-supplemented group (O-3), receiving a blend of linseed and fish oil (60:40). Both groups were fed isoenergetic diets, with ground corn as the control supplement. Total dry matter and net energy intake did not differ between treatments. A treatment-by-time interaction was observed for milk yield, with cows in the O-3 group producing more milk than controls at specific time points. Additionally, O-3 cows had higher overall protein yield and improved feed efficiency. No differences were found in body weight, BCS, glucose, insulin, IGF-1, or urea concentrations, but a tendency toward higher plasma NEFA and BHBA concentrations and lower energy balance was observed in the O-3 group. Supplementation increased plasma cholesterol and progesterone concentrations and was associated with a higher proportion of cows being pregnant at 130 DIM. These findings suggest that omega-3 supplementation may improve specific aspects of lactational performance and reproductive efficiency without compromising metabolic status.

Differential domains of activity of MIR394A and MIR394B gene promoters together with transcriptomic analysis of mutant plants, indicate that miR394 participates in the fine tuning of Arabidopsis flower development through regulation of transcription factors and chromatin remodeling factors. The initiation of flowering is a highly coordinated process that requires synchronization of endogenous plant developmental program with environmental signals through a complex interplay of genetic regulatory networks. We had previously demonstrated a role for miR394 in the regulation of flowering time, since mir394a mir394b plants harboring insertional mutations in the two MIR394 Arabidopsis genes exhibited an early flowering phenotype correlated with modified expression of flowering genes. In the present study we provide transcriptomic RNA-seq data and histologic staining of reporter lines to give further insight into the role of miR394 in the regulation of flowering in Arabidopsis thaliana and present an initial bioinformatic characterization of a newly identified lncRNA, which partially overlaps the MIR394B locus, and therefore we named MIR394B-ASSOCIATED TRANSCRIPT (MIRAST). We found that MIRAST expression is generally low and does not differ significantly between Col-0 and mir394a mir394b mutant plants, allowing for the transcriptomic analysis to focus specifically on the role of miR394 in Arabidopsis flowering. We identified 2405 differentially expressed genes, including 13 transcription factors involved in flower organ development and 7 chromatin remodeling factors. Histologic staining of reporter lines further demonstrated distinct domains of expression for MIR394A and MIR394B genes during flower development. Taken together, our results support a role for miR394 in the fine tuning of Arabidopsis flower development, likely through the regulation of key transcriptional and chromatin remodeling regulators.