University of Buenos Aires

Natural grasslands are among the most threatened biomes due to land-use change and limited protection. The Flooding Pampa, Argentina, harbors well-preserved grasslands used for grazing. Cattle grazing creates habitats dominated by tall or short grasses, affecting grassland birds. We evaluated the influence of two grazing management systems and grassland height on species richness, composition and functional traits of grassland bird communities in winter and spring. Birds and vegetation variables were surveyed along eight transects in six rotational and six continuous grazing ranches. We selected seven functional traits to study their association with grassland height. Cluster Analysis and Linear Discriminant Analysis identified the grassland variables that best described site groupings based on bird composition. Generalized Linear Models compared species richness between groups obtained by Cluster Analysis, and nonmetric multidimensional scaling and fourth corner analysis explored relationships between groups and species composition and functional traits, respectively. In spring, species richness and the richness of tall grassland species were higher in tall grasslands (mean = 27.5 and 3.5, respectively) than in short grasslands (mean = 21.5 and 0.5, respectively), regardless of grazing management. In winter, species richness was similar between tall and short grasslands (mean = 18 and 18.1, respectively). Ranches with tall grass were associated with species associated with tall grassland traits and species of limited abundance. We recommend revising rotational grazing to ensure habitat availability for threatened birds. Conservation policies should aim to reduce stocking rates in continuously grazed short-grass fields and extend rest periods in rotationally grazed short-grass areas.

We demonstrate the scaling of few-cycle post-compression to the multi-TW regime by producing 15 mJ, 6.9 fs pulses through spectral broadening of 800 nm light in a large-bore ( $\oslash$ 1 mm) hollow-capillary fiber (HCF) of 5 m in length. The good beam quality allows for focusing of the beam to near diffraction limit to achieve a peak intensity of 6.5 · 10¹⁸ W/cm² for relativistic laser–matter interaction studies. The performance of the helium-filled HCF is characterized under various operating conditions. We find that a reverse pressure gradient allows for operation above the critical power for self-focusing with >88 ${\% }$ transmission for input energies of 23 mJ.

The last eruptive cycle of Copahue volcano, located on the border between Argentina and Chile, began in 2012 and continues up to the present. One of the characteristics of this volcano is the hot acidic lake located in its crater, which has undergone various changes in the past 20 years, as a result of different eruptive phases. In particular, between 2018 and 2022, changes in the crater lake level were associated with periods of increased surface activity, characterized by phreatic eruptions and SO₂ emissions into the atmosphere. We carried out a multiparametric analysis, finding correlations between the crater lake hydric balance with annual seasonal changes, gas and ash emissions, and temporal variations in the tremor seismic signal. These correlations allowed us to infer that during the cold months, the ambient temperature prevents the thaw that feeds the shallow hydrothermal system, favoring evaporation and reduction of the crater lake volume. Consequently, less efficient heat dissipation and sulfur scrubbing processes favors vent sealing, likely dominated by liquid sulfur and precipitation of secondary minerals in the shallow hydrothermal conduits. Eventually, the gas pressure in the conduits reaches a critical state, which is manifested through increased tremor activity. When the seal is ruptured, an abrupt drop in the seismic signal is observed. This activity is followed by phreatic eruptions or large SO₂ releases into the atmosphere. This crater lake behavior has occurred annually from 2018 to 2022, evidencing a seasonal control on the shallow hydrothermal system and the phreatic activity of Copahue volcano.

[Este artículo está disponible gratis si sigues el link] A medida que la antropología se enfrenta a su pasado, presente y futuro, les antropólogues buscan cada vez más desafiar las desigualdades en la disciplina y en el ámbito académico en general. La antropología, independientemente de la subdisciplina, es una tarea social. Pero la investigación a menudo sigue siendo un proceso que aísla (aunque no necesariamente solitario), incluso cuando se forma parte de un equipo de investigación y en contextos de coautoría. Aquí nos centramos en la publicación evaluada por pares como la principal manifestación de la producción de conocimiento y proponemos un método para desafiar la división, la jerarquía, las diferencias de poder y el apego a la tradición: escribir en comunidad. Escribir en comunidad es una forma colaborativa de escritura que se centra en el cuidado, la abundancia, el regocijo y la satisfacción personal por encima del individualismo que actualmente premia el mundo académico. Este proceso genera consenso, esquiva las jerarquícas normativas de la investigación y la escritura y promueve la creación de relaciones. En esta instancia experimentamos al invitar a revisores y editores a nuestra comunidad para contribuir colectivamente al proceso de escritura y reflexionar juntos sobre esa experiencia. En definitiva, desafiamos las normas de erudición, (co)autoría y modos de conocimiento para ofrecer una práctica más equitativa de la producción de conocimiento. Proponemos que escribir en comunidad puede ayudar a les antropólogues a promulgar valores de multivocalidad y transparencia en la investigación.

RESUMEN En la era digital actual, los datos de salud son cada vez más codiciados, y contar con normas jurídicas que los protejan no es suficiente para evitar su uso indebido, imprudente o improcedente. La ruptura de la confidencialidad o la intrusión, y el acceso irrestricto a datos personales y sensibles constituye un desafío para los países de América Latina y el Caribe. Esto se debe a la coexistencia de actores sociales diversos, marcos normativos inespecíficos, gestión de datos orientadas a aminorar los riesgos informáticos, desigualdades en el acceso y brechas tecnológico-financieras, susceptibles de ser analizadas desde la gobernanza. Estas evidencian una vez más la imposibilidad de la Región para lograr una distribución equitativa de los recursos necesarios para implementar políticas que garanticen el respeto de los derechos humanos. Resulta imperioso, entonces, armonizar los objetivos de desarrollo con las iniciativas destinadas a proteger la confidencialidad y la fuga de datos, a fin de mejorar no solo la reputación, la credibilidad y la confianza en las instituciones, sino también la sostenibilidad de los sistemas enfocada en el ser humano en lugar de en los datos.

Karadöller, Sümer, and Özyürek review a significant body of research underscoring the need to approach early communication as an integrated multimodal system shaped by developmental and interactional dynamics. However, most studies focus on dyadic interactions, overlooking the impact of multiparty communicative contexts not only in Indigenous and low-SES communities but also in daycare settings. Drawing on data from 98 children, we illustrate how multimodal coordination in multiparty interactions differs from dyadic exchanges, emphasizing the role of bystander speech and nonverbal cues in language socialization. We argue that a multimodal framework, accounting for diverse interactional formats, is essential for understanding language acquisition across sociocultural settings.

La principale conséquence sociale du nouveau pouvoir économique planétaire a été d'exclure de l'économie une portion croissante de la population. La relation exploiteur-exploité a fait place à une absence de relation entre inclus et exclus. Le mot « brésilianisation » est utilisé pour désigner un modèle qui se généralise de ratio 20 % d'inclus pour 80 % d'exclus, donnant lieu à une société où des îlots de ghettos riches fortifiés émergent d'une mer de pauvreté. L'objectif le plus immédiat doit être d'introduire une nouvelle dialectique entre exclus et inclus, garantissant aux exclus des conditions minimales d'alimentation, de santé et d'instruction.

Resumen A través de la demostración del hecho que las comparaciones internacionales de delincuencia omiten generalmente la dimensión esencial del sistema penal, el autor da indicaciones para la construcción de un modelo comparativo más adecuado, que integre los diferentes elementos necesarios para la comprensión y la interpretación, en particular la consideración del propio sistema penal como objeto de la investigación comparada.

One challenge in maritime archeology is correlating historical records, archeological findings, and material analysis data to accurately date and establish the provenance of shipwrecks. In the late 18th and early 19th centuries, European naval construction emphasized improvements to the durability of wooden ships, especially for tropical waters. The introduction of metal sheathing was a significant innovation to safeguard ship hulls against wood-boring organisms. Archeometallurgical analysis of copper-based sheathing and fastenings provides crucial insights into shipwreck technology and construction context. This study examines copper sheathing and fastenings on wooden ships from the late 18th to mid-19th century, focusing on wrecks in the Gulf of Mexico. Artifact analysis from these sites sheds light on evolving shipbuilding practices during the early industrial period. Additionally, archeometallurgical analysis has provided chronological references that assist in identifying these wrecks, particularly given the absence of ship hulls, which have degraded under tropical marine conditions.

The effects on the growth of basil (Ocimum basilicum L.) due to the presence of arsenic and vanadium, recently incorporated on the soil, were studied. Besides biomass and morphology, particular emphasis was placed in studying the effect on photosynthetic systems by spectroscopical methods, including reflectance and fluorescence (both stationary and variable) measurements. Assays were conducted in quadruplicate in the presence of arsenic, vanadium and both together, as well as control assays. Arsenic showed stronger effect on growth compared with vanadium, whereas both combined almost stopped growth. The presence of arsenic disrupted the photosynthetic machinery in basil, significantly impairing electron transfer processes within the chloroplasts. Notably, the negative effects on plants were most severe under both contaminants jointly, followed by arsenic alone, whereas vanadium alone showed the lesser effect.

Objective This study aimed to evaluate the immune cell populations in patients with acute myocardial infarction (AMI). Methods The keyword “myocardial infarction” was searched in the Gene Expression Omnibus database, and only transcriptomes from peripheral blood studies of patients with AMI within 12 h of symptom onset were included. Patients without myocardial infarction from the same database were included in the control group. The differential analysis of expressed genes, the enrichment of metabolic pathways associated with the significant genes, and the proportions and absolute values of immune cells between 2 groups (AMI and control) were analyzed. To validate the findings, neutrophil and lymphocyte counts were obtained from blood counts and correlated with creatine kinase-MB levels in 22 patients with AMI from Hospital Geral Roberto Santos. Results Two microarray datasets from the Gene Expression Omnibus database were analyzed, containing a total of 31 eligible blood transcriptome samples. These samples included 14 patients with AMI and 17 non-infarcted patients (control group). Patients with AMI showed significant gene expression differences compared to the control group ( P < 0.05). The enrichment analysis of the significant genes revealed an association with immune cells. The proportions of cell populations in patients with AMI from both datasets revealed an increase in neutrophils and a decrease in T and B lymphocytes, which were statistically significant ( P = 0.018, P = 0.047, respectively). The analysis of absolute cell numbers demonstrated higher neutrophil values and lower T cell values in patients with AMI compared to the control group (all P < 0.05 in GSE61144 and GSE60993 datasets). The data from Hospital Geral Roberto Santos showed that the percentage of neutrophils showed a positive correlation ( r = 0.5, P = 0.018), while the percentage of lymphocytes showed a negative correlation ( r = –0.45, P = 0.034) with creatine kinase-MB levels in patients with AMI. Conclusion This study suggests that data derived from differential cell counts could serve as an additional parameter to diagnose AMI. Neutrophilia and lymphopenia in AMI should not be used as isolated parameters, but they indicate the need for further investigation, particularly in patients with uncertain diagnoses.

In this article, we propose a model of community memory work, inspired by Michael Rothberg’s multidirectional memory and based on a research-intervention experience we carried out with teenagers in marginal areas of suburban Buenos Aires in 2022–2023. We claim that memorial community work can resignify spaces by recreating dedicated memory sites and including new spaces in a multilayered narrative of memory and future that, in essence, puts multidirectionality into action. We will start by analyzing the theoretical, methodological, and pedagogical underpinnings of “Intimate Cartographies in Community,” a research-intervention project we carried out in high schools in marginal areas of suburban Buenos Aires during the years 2022–2023 ( https://edjam.network/project/intimate-cartographies-in-community/ ) and then offer an analysis of the results.

Introduction Screen failure is a major challenge in the enrollment of metabolic dysfunction-associated steatohepatitis (MASH) randomized controlled trials (RCTs) but its impact has not been systematically assessed. Methods We searched PubMed and the Cochrane Library databases for phase ≥2 RCTs of MASH pharmacotherapies in adults using histological inclusion criteria. Screen failure rates (SFRs) were pooled using a generalized linear mixed model. Results Of 67 included RCTs, 58 reported enrollment data. The pooled SFR was 56.28% (95% CI 50.14 to 62.23) in 44949 individuals. The most common reason for screen failure was ineligibility. SFR was higher in more recent trials, globally conducted trials, and trials funded by pharmaceutical companies. Meta-regressions showed an increase in SFR over time and with more trial sites. Discussion Evidence-based strategies to reduce the high SFR in MASH clinical trials are urgently needed.

It is well established that placing an obstacle near a silo outlet reduces the clogging probability in systems approaching the jamming zone, even enhancing the flow rate when the obstacle is optimally positioned. Typically, studies have focused on fixed obstacles in 2D-silo models, using spherical particles, and the underlying mechanisms driving flow rate improvements remain a topic of ongoing research. We investigate experimentally the impact of a pendant mobile obstacle on the discharge flow of lentils using a rectangular flat-bottomed silo with a thickness of several particles. Even when the silo is inside the continuous flow regime, we still observe flow maximization for an optimal obstacle height. By selecting appropriate scaling lengths, we achieve a collapse of the flow rate curves for all aperture sizes studied. Our results indicate that different silo configurations exhibit distinct flow correlations, whose type and extent are crucial for flow rate maximization. Velocity profiles indicate that the obstacle increases particle velocity in the lateral channels surrounding the obstacle. Beyond the optimal height, this effect diminishes, and a sharp drop in velocity is found. This is the first experimental confirmation of previous numerical studies. An analytical model using free-fall particle behavior to describe the flow in the lateral channels provides a good representation of the discharge rate. Graphical Abstract

Combinations of β-lactam-diazabicyclooctane inhibitors (DBOs) like ceftazidime-avibactam (CZA) and imipenem-relebactam (IMR) have shown efficacy in treating KPC-2-producing Klebsiella pneumoniae . However, CZA-resistant K. pneumoniae strains have been identified, often linked to substitutions and/or insertions/deletions in three different loops of KPC: (i) the Ω-loop region (amino acids 164–179), (ii) the 237–243 loop; and (iii) the 266–275 loop. This study investigates the impact of the double deletion ΔG242-T243 present in KPC-14. Our results demonstrate that the lower effectiveness of CZA against KPC-14 can be explained by both increased hydrolysis of ceftazidime and a lower affinity and acylation rate by avibactam. In contrast, the IMR combination was efficient in restoring susceptibility to the KPC-14 producing-clone. Although we also observed a lower affinity and acylation rate for relebactam in KPC-14, this reduction in affinity was accompanied by a loss in the carbapenemase activity, finally resulting in an IMR susceptibility phenotype for KPC-14. Expansion of the substrate profile of KPC-14 toward ceftazidime is associated with a trade-off for carbapenems, other penicillins, and cephalosporins, as well as a higher inhibition by clavulanic acid compared to KPC-2. This study provides a better understanding of how deletions in the 237–243 loop affect the effectiveness of novel DBO-combinations and supports the hypothesis that these mutations result in CZA resistance by other different biochemical mechanisms than mutations in the Ω-loop.

The Electron-Ion Collider (EIC), a next generation electron-hadron and electron-nuclei scattering facility, will be built at Brookhaven National Laboratory. The wealth of new data will shape research in hadron physics, from nonperturbative QCD techniques to perturbative QCD improvements and global QCD analyses, for the decades to come. With the present proposal, Latin America based physicists, whose expertise lies on the theory and phenomenology side, make the case for the past and future efforts of a growing community, working hand-in-hand towards developing theoretical tools and predictions to analyze, interpret, and optimize the results that will be obtained at the EIC, unveiling the role of the glue that binds us all. This effort is along the lines of various initiatives taken in the USA and supported by colleagues worldwide, such as the ones by the EIC User Group which were highlighted during the Snowmass Process and the Particle Physics Project Prioritization Panel (P5).

Background Metabolic dysfunction-associated steatotic liver disease (MASLD) affects more than 30% of the world’s population and is associated with multisystemic comorbidities. We combined multidimensional OMICs approaches to explore the feasibility of using high-throughput targeted circulating proteomics to track systemic organ damage and infer the underlying molecular mechanisms. Methods We evaluated a 92-plex panel of prioritized proteins with pathophysiological relevance to organ damage in serum samples of patients using in-depth phenotyping. We included proteomic data from 60,042 individuals in the discovery and replication stages using diverse study designs and cross-proteomic platforms. We used deconvolution strategies to investigate whether the affected liver participated in the expression of biomarkers of organ damage. To assess cell type-specific transcriptional changes in the selected target, we used liver organoid data. Findings The implicated proteins, including ADGRG1 (GPR56), are deregulated in patients who are at-risk of progressive disease and significant fibrosis. ADGRG1 was validated as a surrogate for organ damage, as it was associated with increased risk of end-stage liver disease, moderate but clinically significant risk of death, chronic obstructive pulmonary disease and ischaemic heart disease over a 16-year follow-up, regardless of the subject’s MASLD status. ADGRG1 liver expression mirrors the circulation pattern. Mechanistic insights show that ADGRG1 shifts its transcriptional profile from low expression to upregulation in cells of the fibrotic and inflammatory niche in response to injury. Conclusions Our study provides a framework for potential mechanisms associated with systemic diseases that facilitates holistic management by stratifying patients with MASLD into subclasses at-risk of extrahepatic manifestations.

The reproductive performance of wild bees is a key determinant of their population persistence. However, few studies have directly examined the environmental drivers of demographic processes using a geographically broad approach. In this study, we explored how biotic and abiotic factors influence the reproduction of solitary, cavity-nesting bees across the Monte Desert ecoregion in Argentina. Using artificial nests and a standardized sampling spanning 2000 km and 20° of latitude, we related key reproductive metrics—nest establishment, offspring production and offspring survival—to latitude, climate and biotic factors (flower abundance, vegetation cover and brood parasitism). Climate was the strongest predictor of bee reproductive performance: warm, humid conditions during the nesting period were associated with reduced nest establishment and offspring survival. Brood parasitism further reduced offspring survival. Across the Monte Desert’s latitudinal gradient, nest establishment peaked at mid-latitudes, while offspring production and survival increased towards higher latitudes. These general patterns matched those of M. leucografa, the most abundant bee species. These findings highlight the sensitivity of wild bee reproduction to climatic conditions, particularly during the nesting period. Our study advances our understanding of the potential impacts of climate change on Neotropical wild bees, where extensive areas are experiencing dramatic land-use changes.