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Femtosecond ultra-short laser pulses can induce various micro- and nanostructural changes in the surface of stainless steel, paving the way for new functionalities in the application of these materials. In this work, UV, visible, and IR femtosecond laser pulses have been utilized on ferritic stainless steel under differing conditions of fluence, pulses per spot and hatch distance. These variables resulted in various compositional and micro- and nanostructural changes on the steel surfaces. The texturing processes which originate these changes can be meticulously designed by selecting the appropriate strategy and laser parameters, leading to Laser-Induced Periodic Surface Structures (LIPSS) and other potential morphologies. A significant problem to consider during the laser treatment of stainless-steel surfaces is the effect that these microstructural modifications, induced by the ultra-short pulses, can have on the corrosion behavior and the brightness of the surface. On one hand, a detailed study of the effect that these treatments can have on the corrosion resistance of the stainless steel under investigation has been conducted. The study shows that under specific conditions, treatments with ultra-short laser pulses maintain the corrosion resistance of the surfaces. On the other hand, the study of the surface brightness after laser treatments, as measured by the Light Reflectance Value (LRV), shows that brightness is only slightly decreased (less than 10 %) for samples where Surface Density of Applied Energy (SDAE) is lower than 2 J/cm2. Furthermore, the diffuse LRV is increased in every textured sample due to the presence of ripples.

Este análisis responde a un estudio cualitativo sobre la eficacia del principio jurídico de la participación ciudadana en la implementación de las políticas públicas educativas en Colombia a nivel básico. Se utiliza una metodología de investigación cualitativa y los resultados permiten contrastar los principales hallazgos bibliográficos y documentales, a partir de un enfoque socio-jurídico el cual pretende reconocer la eficacia del precepto de la participación por parte de los llamados destinatarios de la norma jurídica consagrada en la Constitución Política como en la ley. La reflexión propuesta se hace desde la perspectiva asociada con los procesos de reforma del Estado en América Latina de mediados de la década de 1990, los cuales pretenden implementar estrategias para democratizar y generar confianza en la gestión pública. Este análisis teórico permitió evidenciar los principales desafíos que debe afrontar la participación ciudadana frente a las prácticas institucionales, sobre todo locales, encargadas de la implementación de las políticas públicas de calidad de la educación en el nivel básico

Microplastics in aquatic ecosystems harbor numerous microorganisms, including pathogenic species. The ingestion of these microplastics by commercial fish poses a threat to the ecosystem and human livelihood. Coastal lagoons are highly vulnerable to microplastic and microbiological pollution, yet limited understanding of the risks complicates management. Here, we present the main bacterial groups, including potentially pathogenic species, identified on microplastics in waters, sediments, and commercial fish from Ciénaga Grande de Santa Marta (CGSM), the largest coastal lagoon in Colombia. DNA metabarcoding allowed identifying 1760 bacterial genera on microplastics, with Aeromonas and Acinetobacter as the most frequent and present in all three matrices. The greatest bacterial richness and diversity were recorded on microplastics from sediments, followed by waters and fish. Biochemical analyses yielded 19 species of potentially pathogenic culturable bacteria on microplastics. Aeromonas caviae was the most frequent and, along with Pantoea sp., was found on microplastics in all three matrices. Enterobacter roggenkampii and Pseudomonas fluorescens were also found on microplastics from waters and fish. We propose management strategies for an Early Warning System against microbiological and microplastic pollution risks in coastal lagoons, illustrated by CGSM. This includes forming inter-institutional alliances for research and monitoring, accompanied by strengthening governance and health infrastructures., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Microplastics are emerging pollutants that have been found in different environmental matrices of marine and coastal ecosystems, where they can generate harmful ecological impacts. Little is known about the current state of microplastic pollution in fragile tropical lagoon ecosystems, such as Ciénaga Grande de Santa Marta (CGSM) in the Caribbean coast of Colombia. This study assesses microplastic pollution in surface waters and sediments, and the occurrence of microplastic ingestion in commercially important fish species from CGSM. In waters, microplastic abundances ranged from 0.0 to 0.3 items L -1 while in sediments they varied from 0.0 to 3.1 items kg -1 . The most abundant types of microplastics are fibers and fragments, with polypropylene, polyethylene and high-density polyethylene as the most abundant polymers. Also, 100 (i.e. 21.1%) out of 474 individuals from nine fish species had microplastics in their digestive tracts. Microplastics present in water and sediments and in the digestive tract of the analyzed fish species have similar characteristics, also showing a moderate and statistically significant association. Microplastic abundances are higher near river mouths and in urban areas with a high density of fishing activities and aquaculture infrastructures, which are important sources of contaminants. Microplastic pollution in CGSM represents a threat to the lagoon ecosystem and to local people depending on artisanal fishing. Consequently, effective actions to reduce pollution and its socio-environmental impacts are urgently required., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

There is widespread concern about the increase in cases of human and animal infections caused by pathogenic Vibrio species due to the emergence of epidemic lineages. In Colombia, active surveillance by the National Institute of Health (INS) has confirmed the presence of Vibrio ; however, in routine surveillance, these isolates are not genomically characterized. This study focused on the pangenome analysis of six Vibrio species: V. parahaemolyticus , V. vulnificus , V. alginolyticus , V. fluvialis , V. diabolicus and V. furnissii to determine the genetic architectures of potentially virulent and antimicrobial resistance traits. Isolates from environmental and clinical samples were genome sequenced, assembled and annotated. The most important species in public health were further characterized by multilocus sequence typing and phylogenomics. For V. parahaemolyticus , we found the virulent ST3 and ST120 genotypes. For V. vulnificus , we identified isolates belonging to lineages 1 and 2. Virulence gene homologues between species were found even in non-pathogenic species such as V. diabolicus . Annotations related to the mobilome, integrative mobile and conjugative elements and resistance genes were obtained from environmental and clinical isolates. This study contributes genomic information to the intensified surveillance program implemented by the INS to establish potential sources of vibriosis in Colombia.

Introduction and Objective: In order to determine the effects of hyperbaric oxygenation, 14 Cuban children (8 boys and 6 girls) with affected lesions on the Central Nervous System (CNS), were prospectively studied between September 1994 and September 1995; the patients came from the external consultation of Neuropediatric of the Academic Pediatrics Hospital, Tuna Martyrs, Cuba., Patients and Methods: They were evaluated from the neuropediatric and neurophysiologic point of view and submitted to treatment with hyperbaric oxygenation (HBO). Five patients showed a injury to the CNS by severe asphyxia, seven by generalized infections of CNS, one patient with cerebral damage by craneoencephalic traumatism and other with vasoclusive cerebral crisis of siclemic. The average age of the children was of 4.8 +/- 3.4 years. The symptoms and signs were depending on the type on cerebral damage and its evolution. 100% of the children presented infantile cerebral paralysis (ICP) and epilepsy, most of the children were in treatment with antiepileptic drugs, buy they weren't balanced., Results and Conclusions: Satisfactory response was observed in patients that were oxygenated within the first year of the lesion, with better and faster results.