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This study investigates the rain-initiated mixing and variability in the mixing ratio of selected trace gases in the atmosphere over the central Amazon rain forest. It builds on comprehensive data from the Amazon Tall Tower Observatory (ATTO), spanning from 2013 to 2020 and comprising the greenhouse gases (GHGs) carbon dioxide (CO2) and methane (CH4); the reactive trace gases carbon monoxide (CO), ozone (O3), nitric oxide (NO), and nitrogen dioxide (NO2); and selected volatile organic compounds (VOCs). Based on more than 1000 analyzed rainfall events, the study resolves the trace gas mixing ratio patterns before, during, and after the rain events, along with vertical mixing ratio gradients across the forest canopy. The assessment of the rainfall events was conducted independently for daytime and nighttime periods, which allows us to elucidate the influence of solar radiation. The mixing ratios of CO2, CO, and CH4 clearly declined during rainfall, which can be attributed to the downdraft-related entrainment of pristine air from higher altitudes into the boundary layer, a reduction of the photosynthetic activity under increased cloud cover, and changes in the surface fluxes. Notably, CO showed a faster reduction than CO2, and the vertical gradient of CO2 and CO is steeper than for CH4. Conversely, the O3 mixing ratio increased across all measurement heights in the course of the rain-related downdrafts. Following the O3 enhancement by up to a factor of 2, NO, NO2, and isoprene mixing ratios decreased. The temporal and vertical variability of the trace gases is intricately linked to the diverse sink and source processes, surface fluxes, and free-troposphere transport. Within the canopy, several interactions unfold among soil, atmosphere, and plants, shaping the overall dynamics. Also, the mixing ratio of biogenic VOCs (BVOCs) clearly varied with rainfall, driven by factors such as light, temperature, physical transport, and soil processes. Our results disentangle the patterns in the trace gas mixing ratio in the course of sudden and vigorous atmospheric mixing during rainfall events. By selectively uncovering processes that are not clearly detectable under undisturbed conditions, our results contribute to a better understanding of the trace gas life cycle and its interplay with meteorology, cloud dynamics, and rainfall in the Amazon.

Abstract. The wet-season atmosphere in the central Amazon resembles natural conditions with minimal anthropogenic influence, making it one of the rare preindustrial-like continental areas worldwide. Previous long-term studies have analyzed the properties and sources of the natural Amazonian background aerosol. However, the vertical profile of the planetary boundary layer (PBL) has not been assessed systematically. Since 2017, such a profile assessment has been possible with the 325 m high tower at the Amazon Tall Tower Observatory (ATTO), located in a largely untouched primary forest in the central Amazon. This study investigates the variability of submicrometer aerosol concentration, size distribution, and optical properties at 60 and 325 m in the Amazonian PBL. The results show significant differences in aerosol volumes and scattering coefficients in the vertical gradient. The aerosol population was well-mixed throughout the boundary layer during the daytime but became separated upon stratification during the nighttime. We also found a significant difference in the spectral dependence of the scattering coefficients between the two heights. The analysis of downdrafts and the related rainfall revealed changes in the aerosol populations before and after rain events, with absorption and scattering coefficients decreasing as optically active particles are removed by wet deposition. The recovery of absorption and scattering coefficients is faster at 325 m than at 60 m. Convective events were concomitant with rapid increases in the concentrations of sub-50 nm particles, which were likely associated with downdrafts. We found that the aerosol population near the canopy had a significantly higher mass scattering efficiency than at 325 m. There was also a clear spectral dependence, with values for λ=450, 525, and 635 nm of 7.74±0.12, 5.49±0.11, and 4.15±0.11 m2 g−1, respectively, at 60 m, while at 325 m the values were 5.26±0.06, 3.76±0.05, and 2.46±0.04 m2 g−1, respectively. The equivalent aerosol refractive index results, which were obtained for the first time for the wet season in the central Amazon, show slightly higher scattering (real) components at 60 m compared to 325 m of 1.33 and 1.27, respectively. In contrast, the refractive index's absorptive (imaginary) component was identical for both heights, at 0.006. This study shows that the aerosol physical properties at 60 and 325 m are different, likely due to aging processes, and strongly depend on the photochemistry, PBL dynamics, and aerosol sources. These findings provide valuable insights into the impact of aerosols on climate and radiative balance and can be used to improve the representation of aerosols in global climate models.

The climate effects of atmospheric aerosol particles serving as cloud condensation nuclei (CCN) depend on chemical composition and hygroscopicity, which are highly variable on spatial and temporal scales. Here we present global CCN measurements, covering diverse environments from pristine to highly polluted conditions. We show that the effective aerosol hygroscopicity, κ, can be derived accurately from the fine aerosol mass fractions of organic particulate matter (ϵorg) and inorganic ions (ϵinorg) through a linear combination, κ = ϵorg ⋅ κorg + ϵinorg ⋅ κinorg. In spite of the chemical complexity of organic matter, its hygroscopicity is well captured and represented by a global average value of κorg = 0.12 ± 0.02 with κinorg = 0.63 ± 0.01 as the corresponding value for inorganic ions. By showing that the sensitivity of global climate forcing to changes in κorg and κinorg is small, we constrain a critically important aspect of global climate modelling.

Los bajos índices de productividad se evidencian en el incumplimiento de cronogramas, costos elevados, alto porcentaje de desperdicio de material y, por ende, pérdidas económicas; El presente documento analiza la situación actual de la empresa Maxplot S.A. para determinar los factores críticos que afectan los niveles de productividad que permitan incrementar los niveles de eficiencia a través de metodologías de mejora. Para lograrlo, se estudió las diferentes metodologías de gestión de proyectos que pudieran aplicarse para beneficio de la compañía, y se concluye que la metodología más adecuada es la Last Planner System® (LPS), cuyo sistema permite medir el ritmo en el que se desarrolla el producto, fecha para llevar a cabo la compra de principales elementos de construcción como alternativa para el cumplimiento de los proyectos en el sector de la construcción. Palabras clave: Productividad, eficiencia, Last Planner System, gestión de proyectos ABSTRACT Low productivity rates are evidenced in the non-compliance with schedules, high costs, high percentage of material waste and, therefore, economic losses; This document analyzes the current situation of the company Maxplot S.A. to determine the critical factors that reduce productivity levels that increase efficiency levels through improvement methodologies. To achieve this, the different project management methodologies that could be applied for the benefit of the company were studied, and it is concluded that the most appropriate methodology is the Last Planner System® (LPS), whose system allows measuring the pace in which it is developed. the product, date to carry out the purchase of the main construction elements as an alternative for the fulfillment of projects in the construction sector. Keywords: Productivity, efficiency, Last Planner System, project management.

AbstractSmoke from vegetation fires affects air quality, atmospheric cycling, and the climate in the Amazon rain forest. A major unknown has remained the quantity of long-range transported smoke from Africa in relation to local and regional fire emissions. Here we quantify the abundance, seasonality, and properties of African smoke in central Amazonia. We show that it accounts for ~ 60% of the black carbon concentrations during the wet season and ~ 30% during the dry season. The African smoke influences aerosol-radiation interactions across the entire Amazon, with the strongest impact on the vulnerable eastern basin, a hot spot of climate and land use change. Our findings further suggest that the direct influence of African smoke has been historically relevant for soil fertilization, the carbon and water cycles, and, thus, the development of the Amazon forest ecosystem, even in the pre-industrial era.

Introducción. Una de las patologías más frecuentes del pericardio es la pericarditis, que puede presentarse como pericarditis aguda, subaguda o crónica, derrame pericárdico, taponamiento cardíaco o pericarditis constrictiva. Sin embargo, es una condición infrecuente en la población pediátrica. Métodos. Presentamos una serie de casos de pacientes con pericarditis que fueron llevados a pericardiotomía, drenaje pericárdico y pericardiectomía parcial anterior, entre julio de 2014 y junio de 2023. Se recolectaron las variables demográficas y clínicas, se evaluaron los aislamientos microbiológicos y el manejo recibido. Resultados. Un total de 12 pacientes fueron llevados a manejo quirúrgico mínimamente invasivo; de estos, 58 % pertenecían a comunidades indígenas y residían en zonas rurales. La mitad tenían neumonía asociada. En la mayoría de los casos no se obtuvo aislamiento microbiológico. Conclusión. La necesidad de manejo quirúrgico está determinada por la repercusión en las variables hemodinámicas relacionadas con el derrame y el compromiso pericárdico. La pericardiectomía parcial por toracoscopia es una alternativa en estos casos.

The retinoblastoma (RB) tumor suppressor is functionally inactivated in a wide range of human tumors where this inactivation promotes tumorigenesis in part by allowing uncontrolled proliferation. RB has been extensively studied, but its mechanisms of action in normal and cancer cells remain only partly understood. Here, we describe a new mouse model to investigate the consequences of RB depletion and its re-activation in vivo. In these mice, induction of shRNA molecules targeting RB for knock-down results in the development of phenotypes similar to Rb knock-out mice, including the development of pituitary and thyroid tumors. Re-expression of RB leads to cell cycle arrest in cancer cells and repression of transcriptional programs driven by E2F activity. Thus, continuous RB loss is required for the maintenance of tumor phenotypes initiated by loss of RB, and this new mouse model will provide a new platform to investigate RB function in vivo.

Antimicrobial peptides (AMPs) are important mediator molecules of the innate defense mechanisms in a wide range of living organisms, including bacteria, mammals, and plants. Among them, peptide protease inhibitors (PPIs) from plants play a central role in their defense mechanisms by directly attacking pathogens or by modulating the plant’s defense response. The growing prevalence of microbial resistance to currently available antibiotics has intensified the interest concerning these molecules as novel antimicrobial agents. In this scenario, PPIs isolated from a variety of plants have shown potential in inhibiting the growth of pathogenic bacteria, protozoans, and fungal strains, either by interfering with essential biochemical or physiological processes or by altering the permeability of biological membranes of invading organisms. Moreover, these molecules are active inhibitors of a range of proteases, including aspartic, serine, and cysteine types, with some showing particular efficacy as trypsin and chymotrypsin inhibitors. In this review, we provide a comprehensive analysis of the potential of plant-derived PPIs as novel antimicrobial molecules, highlighting their broad-spectrum antimicrobial efficacy, specificity, and minimal toxicity. These natural compounds exhibit diverse mechanisms of action and often multifunctionality, positioning them as promising molecular scaffolds for developing new therapeutic antibacterial agents.

Introducción. La ingesta de cáusticos continúa siendo un problema de salud pública en los países en vía de desarrollo, por lo que a veces es necesario realizar un reemplazo esofágico en estos pacientes. Aún no existe una técnica estandarizada para este procedimiento. Caso clínico. Masculino de 10 años con estenosis esofágica por ingesta de cáusticos, quien no mejoró con las dilataciones endoscópicas. Se realizó un ascenso gástrico transhiatal por vía ortotópica mediante cirugía mínimamente invasiva como manejo quirúrgico definitivo. Discusión. Actualmente existen varios tipos de injertos usados en el reemplazo esofágico. La interposición colónica y gástrica son las que cuentan con mayores estudios, mostrando resultados similares. Conclusiones. La elección del tipo y posición del injerto debe ser individualizada, tomando en cuenta las características de las lesiones y la anatomía de cada paciente para aumentar la tasa de éxito.

The 72‐foot sailing yacht Eugen Seibold is a new research platform for contamination‐free sampling of the water column and atmosphere for biological, chemical, and physical properties, and the exchange processes between the two realms. Ultimate goal of the project is a better understanding of the modern and past ocean and climate. Operations started in 2019 in the Northeast Atlantic, and will focus on the Tropical Eastern Pacific from 2023 until 2025. Laboratories for air and seawater analyses are equipped with down‐sized and automated state‐of‐the‐art technology for a comprehensive description of the marine carbon system including CO2 concentration in the air and sea surface, pH, macro‐, and micro‐nutrient concentration (e.g., Fe, Cd), trace metals, and calcareous plankton. Air samples are obtained from ca. 13 m above sea surface and analyzed for particles (incl. black carbon and aerosols) and greenhouse gases. Plankton nets and seawater probes are deployed over the custom‐made A‐frame at the stern of the boat. Near Real‐Time Transfer of underway data via satellite connection allows dynamic expedition planning to maximize gain of information. Data and samples are analyzed in collaboration with the international expert research community. Quality controlled data are published for open access. The entire suite of data facilitates refined proxy calibration of paleoceanographic and paleoclimate archives at high temporal and spatial resolution in relation to seawater and atmospheric parameters. Plain Language Summary: The new research sailing yacht Eugen Seibold (ES) enables clean, contamination‐free sampling of air and seawater to better understand the interactions between ocean and climate. For example, the oceans remove increasingly less carbon dioxide (CO2) from the atmosphere the more saturated they are with CO2 (ocean acidification). However, a detailed systematic understanding of air‐sea exchange processes remains to be developed. We analyze air and seawater as well as the exchange of greenhouse gases and other substances such as aerosols and soot (black carbon) between air and seawater at high resolution using modern materials and technologies. Scaled‐down, energy‐efficient, and automated probes developed over the past decade are being used to measure around 50 different characteristics of the marine environment. The work deck at the stern of the boat allows the use of custom‐made water samplers and plankton nets to study the ocean to below 1,000 m depth. In addition, the new data enables a better understanding of past ocean archives, such as the marine plankton accumulated in seafloor sediments, to reconstruct past climate changes. From 2019 to 2022, the S/Y ES sailed in the eastern North Atlantic and will operate in the tropical eastern Pacific until 2025. Key Points: New research platform for contamination‐free sampling of the water column and atmosphere of biological, chemical, and physical propertiesComprehensive marine geochemical analyzes including carbon (e.g., CO2) in air and sea surfaceProxy calibration of paleoclimate archives at high temporal and spatial resolution in relation to seawater and atmospheric parameters [ABSTRACT FROM AUTHOR]

Phytoplankton photosynthesis is the first step of energy capture in the open ocean and is therefore fundamental for global biogeochemical processes and ecosystem functioning. High‐resolution methods are required to fully capture the variability of marine photosynthesis and its environmental drivers. Here, we combine two high‐resolution underway methods to study phytoplankton photophysiology, Fast Repetition Rate fluorometry and Flow Cytometry, along a transect in the North‐East Atlantic Ocean from the polar circle to the equator. Significant spatial distinctions in photophysiological strategies were found between biogeographical provinces. The most pronounced distinction was present between the subarctic North Atlantic and the oligotrophic subtropical gyre, where the latter was typified by high photosystem II (PSII) turnover rates, low pigment‐to‐cell volume ratios, low PSII quantum efficiency and low absorption cross sections for photochemistry in PSII. Small‐scale variability along the transect results from varying diel cycles in photophysiology, possibly governed by light availability and cell metabolism. In general, we found that variability in PSII photochemistry was associated with variability in sea surface temperature, whereas the median mixed layer irradiance could explain more of the variation in the light harvesting capacity of the phytoplankton community. This implies that the expected climate change driven shoaling of the mixed layer may impact phytoplankton light harvesting strategies. Plain Language Summary: Marine photosynthesis is the basis of life in the ocean and therefore plays a fundamental role in the worlds' largest ecosystem. Phytoplankton adjust their photosynthesis to different environmental conditions, such as nutrients and light. Here, we combine data from two high‐resolution methods to study phytoplankton in the eastern North Atlantic Ocean from the polar circle to the equator. We show that the photosynthesis of phytoplankton differs between oceanographic regions and that daily cycles as well as environmental drivers play a role in the observed variability in marine photosynthesis. These insights are important to improve our predictions and understanding of the effects of climate change on marine ecosystems and biological productivity. Key Points: Combining underway methods on a small sailing sampling platform allows for high‐resolution characterization of phytoplankton photophysiologyDistinct photophysiological adaptation per marine biogeographical province reflects prevailing geochemical conditions across spatio‐temporal scalesNon‐linear relationships between photophysiology and environmental variables were present with superimposed diel trends [ABSTRACT FROM AUTHOR]

This article presents a literature review to provide inputs to build a theoretical framework and select a methodology to study the sociolinguistic reality of the Embera Chamí community displaced to the urban context of Bogotá, Colombia. In order to carry it out, a selection and synthesis of 68 printed and electronic documents published since 2000 in databases, digital libraries and websites of various organizations were used. The thematic and content analysis, based on categorization and coding, dealt with three thematic axes: the first axis offers a historical overview of the Embera Chamí community, both nationally and locally, the places of origin and the various causes and effects of the phenomenon of displacement. The second axis succinctly describes the Embera Chamí language phonetically, phonologically and grammatically. The last axis presents concepts such as superdiversity, communities of practice and contact networks of diverse nature, as well as some initiatives for the promotion of the Embera Chamí language and culture. The review suggests the need to establish a dialogue between the concepts arising from sociolinguistic theory, the particular context and the worldview of community members, through empirical ethnographic work that incorporates various data collection mechanisms.