Microorganisms play a crucial role in the stability and functioning of ecosystems, responsible for essential processes such as soil nutrient cycling, plant growth, marine biogeochemical cycles, and human health. The conservation of microorganisms and microbiomes has become a priority in biotechnology and ecosystem sustainability. The preservation of these organisms is crucial not only to maintain biodiversity but also to ensure they continue to fulfill their vital roles in the ecosystem. Their role in maintaining ecosystem stability is urgent and underscores the importance of their conservation. Current conservation techniques, such as cryopreservation, freeze-drying, and storage in dry media, are essential to preserve their viability, genetic stability, and functionality. However, effective conservation goes beyond merely preserving survival; it is crucial to maintain their functionality and genetic diversity intact. Emerging methods, such as the use of nanoparticles, vitrification, and biofilms, have shown great potential to improve the protection of microorganisms from extreme environmental conditions, allowing for more effective and long-term conservation. The development of new conservation technologies is vital to overcoming the limitations of traditional methods. These innovations not only improve the viability and functionality of microorganisms but also facilitate the restoration of degraded ecosystems and foster progress in fields such as medicine, agriculture, and industry. Ensuring the conservation of these organisms is critical to ensuring the health and sustainability of our ecosystems and humanity in the future.
The article examines the seasonal dynamics of As, Pb, Cr, and Cd in the surface waters of the Taxco mining district in Guerrero, located in southwestern Mexico. It quantifies the concentrations of these metals via Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES) and assesses spatial source influences through ArcGIS-based geostatistical mapping. Ecotoxicological responses were assessed in the submerged macrophyte Elodea canadensis, focusing on genotoxic effects and the decline of chlorophyll a, chlorophyll b, and total chlorophyll over a 30-day exposure period at mixed-metal hotspot sites. Seasonal contrasts showed that As, Pb, Cr, and Cd concentrations were higher during the wet season, consistent with enhanced hydrologic mobilization and runoff from mine wastes. Conversely, As levels concentrations peaked in the dry season, likely due to reduced dilution and greater aqueous aqueous persistence relative to particulate partitioning. Despite generally low genotoxic signals, the highest Pb exposure produced approximately 60-65 % DNA damage, indicating a dominant contribution of Pb to mixture toxicity. The overall toxicity ranking followed the order Pb > Cr > Cd > As at both 15-day and 30-day exposures. The parallel decreases in total and individual chlorophyll fractions reflect photosynthetic impairment under mixed-metal stress. However, the moderate pigment loss and time-dependent recovery suggest compensatory physiological mechanisms, such as antioxidant activation and pigment remodeling, that partially offset cumulative damage-particularly under Cr-rich conditions. The spatial clustering of metals near mine-waste discharges zones, combined with seasonally modulated exposure, underscores thejoint influence of source proximity and hydrologic regime on ecological risk. The agreement between geochemical gradients and the physiological responses of E. canadensis supports its use as a reliable bioindicator for mixture toxicity screening in mining-impacted tropical dry-forest watersheds. Overall, the results emphasize: (i) the need to prioritize Pb-dominated mixtures in management actions; (ii) the importance of seasonally targeted monitoring and flow-awere mitigation strategies (e.g., enhance controls during storm season), and (iii) the potential of phytorestoration strategies employing metal-tolerant macrophytes to reduce contaminant loading at the source.Future work focusing on redox/speciation (As(III)/As(V), Cr(VI)/Cr(III)) and bioaccumulation dynamics will refine risk assessments and inform the design pathway-based remediation approaches.
Antecedentes y objetivos Valorar la utilidad de biomarcadores de tipo clínico y estructural obtenidos por tomografía de coherencia óptica (SD-OCT) como predictores de resultado visual tras la cirugía de membrana epirretiniana idiopática (MERi). Materiales y métodos Estudio retrospectivo, observacional y analítico de 50 ojos de 50 pacientes sometidos a cirugía de MERi. Se estudió la agudeza visual mejor corregida (AVMC) preoperatoria (Pre) como biomarcador clínico, y biomarcadores estructurales por SD-OCT: grosor macular central (GMC) pre y postoperatorio (Post); estadio de Govetto Pre, y la presencia de capas ectópicas internas (EIFL), disrupción de capas internas (DRIL), disrupción de capas externas (DCE) y disrupción de zona de interdigitación (DZI) Pre. Resultados Se incluyeron 10 ojos en estadio2, 27 en estadio3 y 13 en estadio4. AVMC Pre: 0,96±0,36 logMAR, y Post: 0,65±0,43 logMAR. GMC Pre: 425,4±91,5μm, y Post: 338,5±73,6μm. Se encontraron diferencias significativas en la AVMC Post entre estadios, con tendencia a peor AVMC en estadios más avanzados. Se encontró una correlación positiva moderada-fuerte entre la AVMC Pre y AVMC Post. La AVMC Post no se correlacionó con el GMC Post, pero sí con el GMC Pre. Aquellos pacientes con uno o más de los biomarcadores EIFL, DRIL, DCE y DZI tendieron a un peor resultado visual. Conclusiones Una peor AVMC inicial, mayor GMC Pre y la presencia de EIFL, DRIL, DCE y/o DZI (asociados a estadios más avanzados) se traducen en una peor visión postoperatoria. Una cirugía temprana pudiera conferir mayores probabilidades de un mejor resultado visual.
In this work, a novel strategy is developed to implement a trajectory tracking controller for a two-degree-of-freedom underactuated control moment gyroscope (CMG). A change of variables is first performed to obtain a convenient form that facilitates the interconnection between the actuated and underactuated gimbals. A model-based controller is proposed to ensure asymptotic tracking of the actuated gimbal to a reference signal. This reference is designed under a singular perturbation framework, and the Tikhonov solution is employed to generate a signal that guarantees asymptotic trajectory tracking of the underactuated gimbal. Theoretical stability analysis and numerical simulations are presented to validate the proposed approach.
Introducción: La educación física (EF) constituye la base de la alfabetización motriz, clave para el desarrollo multidimensional del ser humano. En este sentido, la EF de calidad ha sido señalada como un eslabón inicial en la trayectoria hacia el alto rendimiento deportivo (ARD). Objetivo: Sintetizar la evidencia científica disponible sobre la relación entre la EF de calidad y el ARD, evaluando la pertinencia metodológica de los estudios publicados en la última década. Metodología: Se realizó una revisión sistemática siguiendo la guía PRISMA en cuatro bases de datos (Google Académico, SciELO, Dialnet y Scopus), incluyendo estudios publicados entre enero de 2015 y julio de 2025. Se identificaron inicialmente 250 registros; tras eliminar duplicados y aplicar criterios de inclusión y exclusión, se evaluaron 20 artículos a texto completo, de los cuales 6 fueron incorporados en el análisis final. La calidad metodológica de las revisiones sistemáticas se evaluó mediante AMSTAR 2. Resultados: 3 estudios presentaron bajo riesgo de sesgo (revisiones sistemáticas de calidad), 1 riesgo moderado y 2 riesgos altos. La evidencia converge en que programas de EF estructurados y bien diseñados potencian el desarrollo psicomotor y la identificación de talentos, considerados predictores del rendimiento deportivo en etapas posteriores. Sin embargo, persiste heterogeneidad conceptual y escasez de estudios longitudinales. Conclusiones: La EF aparece como un factor determinante en las trayectorias hacia el ARD. No obstante, se requieren investigaciones sistemáticas y longitudinales para reforzar la solidez de la evidencia y generar recomendaciones aplicables a políticas públicas. DOI: https://doi.org/10.54167/rmccf.v6i12.2085.
