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En el presente estudio se analiza el proceso de acorazamiento (blindaje) que se presenta en el río La Miel (Colombia), un importante río tropical regulado y fuertemente modificado en sus regímenes hidrológicos, hidráulicos y sedimentológicos. Para confirmar la hipótesis del acorazamiento se emplean tres enfoques diferentes: 1) verificación cualitativa del proceso de acorazamiento realizada durante un recorrido de campo, 2) verificación cuantitativa del acorazamiento empleando el criterio definido por Little y Meyer (1976) para la desviación geométrica estándar de la granulometría del lecho (determinada con el software BASEGRAIN) y 3) análisis de los registros de carga de sedimentos en suspensión y de fondo en las estaciones de monitorio hidrosedimentológico. Los resultados indican que el río La Miel efectivamente se encuentra acorazado según la evidencia de campo y la marcada disminución en la carga de sedimentos de fondo, además, se identifica que el proceso de acorazamiento se ha dado en escalas de tiempo más cortas que las reportadas en la literatura para ríos extratropicales, debido al exceso de capacidad de transporte producido por el aumento sistemático de los caudales mínimos luego de la regulación y los transvases de los ríos Guarinó y Manso. Por otro lado, podemos indicar que efectivamente existe un umbral de caudal importante (234 m3/s) el cual se debe superar para que se rompa la coraza y se registre transporte de la carga de fondo.

AbstractWe reported an outbreak of wild rabies in Potus flavus (choznas), a carnivorous mammal associated with insectivorous bats in Kosñipata, Cusco, Peru, from February 2021 to October 2022. Eight human exposures were reported, with aggressive attacks resulting in injuries. The outbreak prompted a public health response and raised concerns about zoonotic diseases due to habitat fragmentation and urbanization. The study involved antigenic and genetic characterization of the virus in the affected animals, revealing similarities with variants in non-hematophagous bats. This outbreak marked the first time rabies had been reported in choznas in the region, highlighting the need for early intervention programs and wildlife protection. Pre-exposure rabies vaccinations were administered to residents, and community surveillance was established to control the outbreak. The study emphasizes the importance of continuous surveillance and education to prevent rabies transmission from choznas to humans and other animals, as their role as potential secondary transmitters of the virus warrants further investigation.

Se presenta la metodología utilizada para la determinación de umbrales asociados a avenidas torrenciales en el municipio de Mocoa – Putumayo (Colombia). Estos se proponen en términos de precipitación, cota de nivel del agua (msnm) y caudal; y se obtuvieron con soporte en la modelación basada en la física de un escenario de avenida torrencial y su afectación a viviendas cercanas al cauce. Se determinaron también umbrales lluvia - deslizamiento con base en el análisis probabilístico de curvas reportadas en la literatura y su comparación con dos eventos previos ocurridos en Mocoa. Se evidencia la necesidad de la redundancia en la propuesta de los umbrales dada la alta incertidumbre epistémica y aleatoria incluida en el proceso de modelación física, la complejidad del proceso en la ocurrencia de una avenida torrencial y su posterior impacto sobre la protección de la vida, principal objetivo de la gestión del riesgo de desastres, en caso de que el sistema de alerta temprana no tenga el funcionamiento adecuado. Por primera vez se presenta un procedimiento para la generación de los umbrales para un Sistema de Alerta Temprana de avenidas torrenciales en Colombia proveniente de un análisis físico integrado articulado con análisis probabilistas de la información disponible.

Road structures undergo a series of chemical and physical processes once they are put into service. This phenomenon results from the action of the load and the influence of the environment, which causes their progressive deterioration. In order to mitigate the risk of progressive deterioration and guarantee their stability and durability, various maintenance tasks are required, including visual inspections. The Intelligent Bridge Management System of Colombia (SIGP) includes visual inspection as one of its modules. The system has been designed based on state-of-the-art criteria and national experience with relevant damages and bridge collapses. This paper presents the visual inspection methodology, which includes several stages such as a classification scale, condition index, evaluation areas, damage catalog, and evaluation criteria. In addition, a digital application has been developed to facilitate real-time data collection during field inspections using mobile devices, which can be uploaded directly to the system database hosted in the cloud. The results from the inspection of bridges of different typologies and years of construction are presented, as well as general inspection results from 150 bridges in Colombia. The relevance, comprehensiveness, and accuracy of the inspection are supported by a damage catalog, which allows the identification of intervention needs and reduces the bias of the collected data.

Introduction: Although freshwater ecosystems encompass 12% of all known species, their study has achieved less progress in systematic conservation planning exercises compared with terrestrial and marine ecosystems. Moreover, little attention has been given to ecosystem services and cultural and spiritual values, which are pivotal in the long-term preservation of freshwater ecosystems. Conservation, restoration, and sustainable management actions within freshwater systems are currently addressed individually, underscoring the necessity of comprehensive methodological frameworks that holistically address the questions of where and how to conserve while integrating ecosystem services and cultural factors as conservation values.Methods: We propose a new methodological framework for the conservation of freshwater ecosystems that incorporates these elements and fulfills six prioritization criteria: 1) representativeness, 2) integrity, 3) importance, 4) rarity, 5) complementarity, and 6) connectivity. To illustrate the application of this approach, we conducted a regional study in the Caquetá River basin in Colombia.Results: By applying our methodological framework, we demonstrated that the Caquetá River basin hosts 518 distinct freshwater groups with unique characteristics that contribute to the maintenance of ecosystems and the preservation of their inherent values. Additionally, our analysis revealed that protection is the most effective conservation strategy for 77.4% of the Caquetá River basin, whereas restoration and sustainable management are suitable for 4.7% and 17.9% of the basin, respectively. The prioritized portfolio for the Caquetá River basin encompasses 80.1% of all freshwater groups, effectively meeting The Nature Conservancy’s proposed conservation objectives.Conclusion: This novel methodological framework provides a pragmatic approach to systematic conservation planning and answers the questions of both where and how to conserve.

Introduction: Despite its central role in medicine electrical stimulation (ES) is still limited by its selectivity. Different reports did assess effects of different waveforms, intensities, and frequency on the activation threshold of nerve fibres with different diameters. We aimed to extend this knowledge by investigating the effect of short monophasic rectangular pulses (1, 2, 5, 10, 50, 100 and 200 μs) on the recruitment order. Methods:The sciatic nerve of rats was stimulated, and the evoked compound nerve action potential (CNAP) measured at two sites on the tibialis nerve, using epineural electrodes. Changes in delay, amplitude, and the shape of the CNAP were analyzed. Results:The amplitude and delay of the CNAP were significantly affected by the pulse-width (PW). The delay and duration of the compound nerve action potential increased with longer PW, while the amplitude decreased. Discussion:Found changes are likely caused by changes in the time point of excitation of individual neuron fibres, depending on electrical field strength and exposure time. This might be of particular interest when selecting PWs for design and validation of stimulation patterns and analysis of experimental and clinical observations.

Abstract Background Salicylic acid participates in the regulation of the plant's response to a series of environmental stresses such as extreme temperatures, salinity, and oxidative condition of potato growth, so it is necessary to determine a safe application dosage for potato in field conditions. Methods The purpose of the research was to evaluate the effect of increasing doses of acetylsalicylic acid on the agronomic traits of two potato cultivars in Lima, Peru. In a field experiment, an RCBD with 3 replications was used under a split-plot arrangement in which five doses (0.0, 0.2, 0.4, 0.6, and 0.8 mM) of acetylsalicylic acid plus control with Biol (biostimulant) were assigned to plots, and two potato cultivars ('Perricholi' and 'Unica') were assigned to subplots. The average temperatures were between 15 and 21º C, the air relative humidity was between 61 and 73% and the soil was loam textural class, free of salts. Results No statistical differences were found for the number and weight of tubers and biomass due to the effect of the application of the treatments. The effects of doses of acetylsalicylic acid showed statistical differences for sprouting, vegetative vigor, and percentage of flowering; likewise, significant interactions (p

In Colombia, most of the energy is produced by using water resources. However, the morphological impact of damming has not been thoroughly studied yet. Therefore, upstream and downstream changes in the channel width and sinuosity along the river due to the Betania, Prado, Salvajina, and Urrá I Dams, four of the oldest hydroelectric projects, were estimated. These changes were reported by using aerial photographs and satellite images to compare the river before and after dam construction. The analysis was complemented by including hydrological trends and geological characteristics of the areas to evaluate their relevance on the impacts on channel morphology. It was shown that factors such as valley confinement and the bank’s composition are key to determining the magnitude of the impact downstream of the dam. Upstream of the dam, contrastingly, the influence of the reservoir geometry controls the magnitude of the morphological changes, marking the boundaries of affected areas. The impacts of dam construction on river morphology vary notably, but including the geological characteristics of the river reach can be useful to improve predictions of the channel morphology response. The proposed methodology can be used to identify biotic compensation measures for new projects, a task that is not well defined in several countries.

Pulmonary function tests are vital for detecting pathologies, especially chronic obstructive pulmonary diseases (COPD), emphasizing the importance of assessing lung parenchyma involvement in maintaining proper gas exchange. Electrical impedance tomography (EIT) offers a non-invasive alternative for respiratory function evaluation while preserving natural breathing. We propose using EIT to detect lung parenchyma conditions by analyzing tidal volume patterns (by averaging the impedance image) in the frequency domain. Twenty COPD patients underwent simultaneous evaluation with a pneumotachometer and an EIT device, performing three 30-second respiratory maneuvers. FFT spectra analysis yielded parameters, including the area under the curve and quartiles (25 %, 50 %, 75 %) of power values in six frequency regions. Correlations between these parameters and clinical test results (pulmonary diffusing capacity and arterial blood gas analysis) revealed significant associations, particularly with PCO2. Multiple linear regression analysis predicted PCO2 with an R2adj = 0.827, suggesting the potential for noninvasively detecting lung parenchyma affectation by correlating FFT bioimpedance ventilatory patterns with gas exchange performance in COPD patients. [ABSTRACT FROM AUTHOR]

Road structures undergo a series of chemical and physical processes once they are put into service. This phenomenon results from the action of the load and the influence of the environment, which causes their progressive deterioration. In order to mitigate the risk of progressive deterioration and guarantee their stability and durability, various maintenance tasks are required, including visual inspections. The Intelligent Bridge Management System of Colombia (SIGP) includes visual inspection as one of its modules. The system has been designed based on state-of-the-art criteria and national experience with relevant damages and bridge collapses. This paper presents the visual inspection methodology, which includes several stages such as a classification scale, condition index, evaluation areas, damage catalog, and evaluation criteria. In addition, a digital application has been developed to facilitate real-time data collection during field inspections using mobile devices, which can be uploaded directly to the system database hosted in the cloud. The results from the inspection of bridges of different typologies and years of construction are presented, as well as general inspection results from 150 bridges in Colombia. The relevance, comprehensiveness, and accuracy of the inspection are supported by a damage catalog, which allows the identification of intervention needs and reduces the bias of the collected data. [ABSTRACT FROM AUTHOR]

Molecular phylogenetic studies of the six currently accepted species in the genus Echinocactus have partially clarified certain aspects of its phylogeny. Most of the studies lack a complete sampling of Echinocactus and are based only in one source of data. Phylogenetic uncertainties in Echinocactus, such as the recognition of Homalocephala as a different genus from Echinocactus, the exclusion of E. grusonii or the affinities of E. polycephalus, are here resolved. Phylogenetic relationships of Echinocactus were reconstructed with a maximum parsimony, a maximum likelihood and a Bayesian approach including 42 morphological characters, four chloroplast markers (atpB-rbcL, trnH-psbA, trnL-trnF and trnK/matK) and two nuclear genes. The utility of these two nuclear regions related to the betalain cycles (DODA and 5GT) are explored and discussed in relation to their potential as phylogenetic markers. Concatenated analyses with morphological and molecular data sets, plus 13 indels (2847 characters and 26 taxa), show general agreement with previous independent phylogenetic proposals but with strong support in order to propose the recognition of a reduced Echinocactus and the recognition of Homalocephala at the generic level. These results recovered a polyphyletic Echinocactus as currently defined. The here-named HEA clade, recovers the species of Homalocephala, Echinocacuts and Astrophytum as a monophyletic group with strong internal support. The Homalocephala (H. texensis, H. parryi and H. polycephala), was recovered as sister to the Echinocactus clade (E. platyacanthus and E. horizonthalonius), plus the Astrophytum clade. Consequently, we propose here to recognise a monophyletic Echinocactus and a monophyletic Homalocephala as two distinct genera with their own molecular and morphological synapomorphies. The evolution of some morphological characters supporting these clades are discussed, the necessary new taxonomic combinations for Homalocephala are proposed and an identification key for the genera, the species and the subspecies of the HEA clade are presented.

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