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Study question Are the extracellular vesicles (exosomes and microvesicles) presented in seminal plasma a potential novel biomarkers of male infertility? Summary answer There are significant differences in surface molecules (CD9, CD29, CD40, CD49d, CD73, CD282 and CD284) expressed in extracellular vesicles of patient and control groups What is known already Male infertility has been progressively increasing in recent decades. Therefore, it is essential to find new tools that help us to diagnose the male factor. One of the potential markers could be the study of the extracellular vesicles (EV), mainly exosomes (EXO) and microvesicles (MV), present in the seminal plasma. Recent works have shown that these extracellular vesicles would have an important role in the modulation of the maternal immune system, as well as in regulating the sperm activation. Therefore, the study of the extracellular vesicles can be a useful model to increase the diagnosis of the infertile male Study design, size, duration This prospective study, performed between March 2019 to January 2022, included 44 semen samples from healthy semen donors (control group) and 44 semen samples from infertile males seeking infertility treatment with their partners (study group). Men under drug treatment and/or with infectious or chronic diseases were excluded from the study Participants/materials, setting, methods After conventional semen analysis, semen samples were ultra-centrifuged to obtain EVs enriched plasma seminal. The samples were then stained with fluorescent antibodies against the following surface molecules: CD81, CD63, CD9, CD40, CD44, CD49d, CD73, CD284 and CD29. After incubation, samples were analyzed by flow cytometry (Cytoflex cytometer) The percentage and mean expression of each molecule in EVs populations (EXOs and MVs) were determined. Statistical analysis was performed by t-Student test; significance established under 0.05 Main results and the role of chance Conventional semen analysis showed significant differences between control and patient group in sperm concentration (77.2 · 106 vs 40.2 · 106 cells / ml, respectively, p Limitations, reasons for caution This study enrolled male partners of couples seeking infertility treatment with dissimilar disorders and seminal diagnosis (astheno, oligo, and teratozoospermia). Therefore, further studies are needed lowering the heterogeneity of the study group. No data about reproductive outcome of these patients are available at this moment Wider implications of the findings These results suggest that the differences found in the expression profiles between men with proven fertility and infertile men may be related to molecular mechanisms implicated in sperm function, and/or female immune system modulation and, for that reason, may be used as a new potential marker of male fertility Trial registration number 1904-MAD-045-AP

En el presente estudio, se pretende conocer la situación actual de las empresas del sector alimentos en Barranquilla, analizando las variables del entorno económico mundial, latinoamericano, colombiano, región caribe, departamento del Atlántico, hasta llegar a la ciudad de Barranquilla; teniendo como base la perspectiva de diferentes investigaciones con puntos de incidencia. Se plantea las características de las empresas de alimentos, con el propósito de aumentar la competitividad, se establece entre las principales acciones; es estratégico invertir en el desarrollo de los proveedores de las materias primas con prácticas ambientales eficientes, crear nuevos productos y mantener una buena imagen para posicionar y así ampliar el mercado. Los dirigentes del Atlántico deben dirigir sus esfuerzos en buscar nuevos inversores económicos, articular con las principales instituciones del gobierno que invierten con recursos económicos o factor humano tanto en el sector rural y urbano para las pequeñas y medianas empresas. El gobierno rige un papel fundamental para aplicar medidas como reducir incertidumbre de reforma tributarias, disminuir el contrabando, invertir en aumentar las capacidades de las empresas como productividad, calidad y estrategias de comercialización, disminuir los efectos de los fenómenos del clima por medio del desarrollo de medidas de mitigación y regulación, controlar los principales factores que potencializan la depreciación del peso por medio de acciones a largo plazo, simplificar las restricciones de entrada y salida de alimentos para no afectar la producción de alimentos, competitividad y por ende el crecimiento económico del sector.

Barrier islands in tropical regions are prone to coastal flooding and erosion during hurricane events. The Yucatan coast, characterized by karstic geology and the presence of barrier islands, was impacted by Hurricanes Gamma and Delta in October 2020. Inner shelf, coastal, and inland observations were acquired simultaneously near a coastal community (Sisal, Yucatan) located within 150 km of the hurricanes’ tracks. In the study area, Gamma moved at a slow speed and induced heavy rain, mixing in the shelf sea, and northern winds exceeding 20 m s-1. Similar wind and wave conditions were observed at this location during the passage of Hurricane Delta. However, a higher storm surge (0.5 m) was measured due to wind setup and the drop (< 1000 mbar) in atmospheric pressure. Beach morphology changes, based on GPS measurements conducted before and after the passage of the storms, show alongshore gradients ascribed to the presence of coastal structures and macrophyte wracks on the beach face. Moreover, net onshore sediment transport during the storm contributes to the increase in beach elevation. Urban flooding occurred mainly on the back-barrier associated with heavy rain and the confinement of the coastal aquifer which prevented rapid infiltration. Two different modeling systems, aimed at providing coastal flooding early warning and coastal hazards assessment, presented difficulties in forecasting the coastal hydrodynamic response during these seaward translating events, regardless of the grid resolution and wind forcing employed. Compound flooding plays an important role in this region and hence must be incorporated in future modeling efforts.

Terrestrial biodiversity is higher in topographically complex regions than in low relief ones, and this diversity evolved over millions of years along elevation gradients with disequilibrium of climatic conditions and biological interactions. Also, the mountainous complex is heterogeneous, consisting of orogenic and volcanic mountains with different geological and climatic features. However, there has not been an investigation in regard how a volcanic environment may have influenced ecosystem changes or faunal evolution to. Rodents are an excellent model to explore these questions because they are the most speciose clade of mammals and many species live in montane regions. Hypotheses of the ecological evolution in different volcanic provinces in America were discussed during the Workshop on Volcanism and Rodent Evolution organized by the Research Group “Mammal diversification about dynamic landscapes of the North American Rodents Landscapes, Evolution & Ecology”. Workshop consisted of two modules: 1) origin and development of volcanic provinces in North America during the late Cenozoic with an emphasis on the geological process crucial to the ecosystem; 2) some examples of ecosystems in volcanic regions and evolutive patterns related to sky-island process. In both modules, we discuss the evolution of different lineages of rodents, fossil and extant species, and how we can distinguish the volcanic influence on their biodiversity. The topics were: speciation, endemism, genetic drift, geographic-range shifts, environmental sorting, and sky-island processes.

Spa: Esta investigación surge de la inquietud que generan los resultados poco favorables en el área de Ciencias Naturales en la Institución Educativa Colegio de Sugamuxi de Sogamoso, Boyacá con respecto a las pruebas que evalúan la calidad educativa, como también el contraste que se hace con otras áreas como matemáticas y castellano que se encuentran por encima de los promedios que obtiene el área de Ciencias Naturales. El propósito fue desarrollar una propuesta de cualificación en competencia de indagación centrada en el aprendizaje basado en problemas. Se propuso tres objetivos, el primero, caracterizar las concepciones que los docentes del área de Ciencias Naturales de la Institución Educativa Colegio de Sugamuxi tiene sobre la indagación, segundo, diseñar e implementar una propuesta de formación que permita incentivar la competencia específica de indagación del área de Ciencias Naturales en los docentes de la Institución Educativa Colegio de Sugamuxi y tercero, Evaluar el modelo de trabajo con los docentes del área al implementar el Aprendizaje Basado en Problemas con los estudiantes de grado 6C. El alcance de estos objetivos permitió el cumplimiento del objetivo general que fue desarrollar una propuesta de cualificación docente en la competencia de indagación centrada en el Aprendizaje Basado en Problemas, con docentes de Ciencias Naturales de la Institución Educativa Colegio de Sugamuxi. Los fundamentos teóricos que apoyaron esta investigación se basaron en tres miradas: la primera, lo que plantea el Instituto Colombiano de la Evaluación de la Educación acerca de la competencia de indagación; la segunda, referente a la enseñanza de las ciencias basada en indagación, y la tercera, el Aprendizaje Basado en Problemas. Metodológicamente, el trabajo se abordó a partir de los postulados del paradigma crítico social, con un enfoque cualitativo y un tipo de investigación acción pedagógica. Se desarrolló en tres fases: a. diagnóstico sobre los conocimientos que tiene los docentes sobre indagación; b. diseño e implementación de la propuesta; y c. evaluación del proceso. Las técnicas de recolección de información correspondieron a un grupo focal, la observación y la encuesta, y los instrumento que se utilizaron para recolectar la información fueron el cuestionario y diario de campo. La formación en los docentes se consideró un espacio de transformación necesario, en el cual se generó un intercambio de ideas y de propuestas que se basaron siempre en las necesidades de la institución, así mismo se reflexionó sobre problematizar los planes de mejoramiento institucional, de área y de aula, en algunos de los aspectos que lo componen, como en este caso la competencia de indagación. Los docentes que participaron en este proceso investigativo valoraron el trabajo realizado y lo propusieron como un espacio de formación continua., Bibliografía y webgrafía: páginas 95-107., Maestría, Magister en Educación

In order to achieve high yields, the use of radiation by agricultural crops must be improved in order to maximize and extend the duration of foliar interception of solar radiation. Appropriately, studies aimed at the understanding and behavior of radiation in plants are extremely relevant. Accordingly, the objective of this study was to approach information about the concepts, radiation availability temporal, geographical, photosynthesis efficiency as a function of leaf arrangement and radiation interception efficiency × leaf area index (LAI). Studies aimed at a significant comprehension of radiation in crops demonstrate that the plant growth and development depend on the intensity and duration of solar radiation. More surveys are required on the subject for a better development of the culture, aiming to guarantee that the plants have better conditions to express their potential.

The Ring of Cenotes (RC) extends along the edge of the Chicxulub crater, in the limestone platform of the Yucatan Peninsula (YP), where groundwater shows two preferential flow paths toward the coast near Celestun and Dzilam Bravo towns. The objectives of this study were to describe the regional hydrogeochemical evolution of the groundwater in the RC, and its association with the dissolution/precipitation of the minerals present along its pathway to the ocean. These objectives results were obtained by: a) characterizing groundwater hydrogeochemistry, b) calculating calcite, dolomite, and gypsum saturation indexes in the study area, and c) developing a hydrogeochemical model using PHREEQC (U. S. Geological Survey) inverse modelling approach. The model predictions confirmed that there are two evolution pathways of the groundwater consistent with the preferential flow paths suggested in a previous regionalization of the RC. On the western path, where groundwater flows towards Celestun, marine intrusion influences the hydrogeochemical processes and represents a risk for the freshwater. On the eastern path, where groundwater flows toward Dzilam Bravo, rainfall has an important effect on the hydrogeochemical processes, evidenced by a higher concentration in sulfates during droughts than during rainy periods. Then, monitoring of marine intrusion and phases dissolution in the RC is highly recommended

Karst aquifers show dissolution/precipitation processes of the minerals present in the carbonate rocks. The Ring of Cenotes (RC) extends along the edge of the Chicxulub crater, in the limestone platform of the Yucatan Peninsula (YP), where groundwater shows preferential flow paths toward the coast near Celestun and Dzilam Bravo towns. This study aimed to describe the regional hydrogeochemical evolution of groundwater of the RC, and its association with the dissolution/precipitation of the minerals present along its path to the ocean. To achieve this aim, we: a) characterized groundwater's hydrogeochemistry; b) determined the calcite, dolomite, and gypsum saturation indexes (reaction phases with the groundwater) in the study area; c) proposed a hydrogeochemical model developed through PHREEQC using an inverse modelling approach. The model predictions confirmed that there are two evolution pathways of the groundwater consistent with the preferential flow paths suggested in a previous regionalization of the RC. On the western path, where groundwater flows towards Celestun, an important marine intrusion influences the hydrogeochemical processes and represents a risk for the prevalence of freshwater. On the eastern path, where groundwater flows toward Dzilam Bravo, the hydrogeochemistry in the sinkholes correlates well with rainfall, suggesting a higher vulnerability during droughts than during rainy periods.

El conflicto armado colombiano deja millones de personas víctimas de migración interna, lo que implica la obligada interacción de las personas afectadas con marcos normativos que pretenden reestablecer sus derechos y la institucionalidad que lo ejecuta. Todo lo anterior moviliza procesos psicológicos, sociales, administrativos y judiciales que trascienden desde lo individual a lo colectivo y viceversa; estos aspectos han sido poco visibilizados y demandan ser estudiados desde diferentes disciplinas; es así como el presente estudio pretendió reconocer desde una mirada cualitativa y psicojurídica las representaciones sociales que surgen en esta población producto de la dinámica mencionada, a través de la aplicación de 20 entrevistas grupales e individuales con población desplazada en Montería. Como resultado se evidenció el sentir común hacia la normatividad que expresa ideas de: insatisfacción, abandono, revictimización e inoperancia; un elemento que llamó la atención es la adecuación del lenguaje de las víctimas que incorpora elementos jurídicos como respuesta adaptativa resiliente en su propio marco de representación de la ley. El artículo finaliza proponiendo una pregunta entorno a la noción de < Representación Psicojurídica> como propuesta para avanzar hacia estudios en contextos jurídicos disimiles. The Colombian armed conflict leaves millions of people victims of internal migration, which implies the obligation of people to interact with regulatory frameworks that seek to reestablish their rights and the institutions that execute it. All of the above mobilizes psychological, social, administrative and judicial processes that transcend from the individual to the collective and vice versa; These aspects have been little visible and demand to be studied from different disciplines; Thus, the present study sought to recognize from a qualitative and psycho-legal perspective the social representations that arise in this population as a result of the aforementioned dynamics, through the application of 20 group and individual interviews with displaced population in Montería. As a result, common sense towards regulations expressing ideas of: dissatisfaction, abandonment, revictimization and ineffectiveness is evident; An element that specifies care is the adaptation of the language of the victims that incorporates legal elements as a resilient adaptive response in its own framework of representation of the law. The article ends by proposing a question around the notion of as a proposal to advance towards studies in dissimilar legal contexts. Magíster en Psicología Jurídica Maestría

The company Metro Caribe made an approach to the Universidad del Norte, where the problems presented by Transmetro were explained. The losses are in the fuel consumption, because only the air conditioning consumes 40% of the Diesel. Subsequently, a target was set for a savings target of close to 30 per cent. To solve the problem, 3 alternatives were established: Total hybridization of the bus powered by a fuel cell (PEM), the implementation of a Diesel generator for partial loads and a hybrid transmission kit; the latter being the selected alternative, together with a regenerative braking system. In order to reduce costs, by independent consumption of miscellaneous power of the thermal engine. The project focuses on the cooling system, its working parameters and the variability of costs. During the project, with the help of isoconsumption maps, the operating regimes were analyzed, thus evaluating the different technologies found in the market and the optimal working conditions. Finally, the implementation of these technologies, such as the replacement of the compressor used, showed considerable levels of savings in the fuel consumption of the fleet; which shows that the alternative selected, in terms of design and implementation, is a possible solution to the problem. In order to obtain more precise simulations of the operation, it is recommended to make measurements, within the operating parameters, of the different vehicle consumption. La empresa Metro Caribe realizó un acercamiento a la Universidad del Norte, en el cual explicó la problemática que presenta Transmetro, operando en Barranquilla. Las pérdidas radican en el consumo del combustible, debido a que sólo el aire acondicionado consume el 40% del Diésel. Posteriormente, se estableció un objetivo para trazar un valor meta de ahorro cercano al 30%. Para subsanar la problemática, se establecieron 3 alternativas: La hibridación total del bus potenciado por una celda de combustible (PEM), la implementación de un generador Diésel para cargas parciales y un kit de trasmisión híbrida; siendo esta última la alternativa seleccionada, en conjunto a un sistema de frenado regenerativo. Con el fin de aminorar los costos, al independizar el consumo de potencias misceláneas del motor térmico. El proyecto se centra en el sistema de refrigeración, sus parámetros de trabajo y la variabilidad de los costos. Durante el proyecto, con ayuda de los mapas de isoconsumo, se analizaron los regímenes de operación; evaluando así las diferentes tecnologías encontradas en el mercado y las óptimas condiciones de trabajo. Para finalizar, la implementación de dichas tecnologías, tales como la sustitución del compresor utilizado, permitió evidenciar niveles considerables de ahorro en el consumo del combustible de la flota; lo cual demuestra que la alternativa seleccionada, en materia de diseño y de ejecución, es una posible solución ante el problema. Con la finalidad de obtener simulaciones más precisas, del funcionamiento, se recomienda realizar mediciones, dentro de los parámetros operativos, de los diferentes consumos del vehículo.

There are limited economic and reliable tools to monitor the effects of airborne particulate matter PM originating from rapid industrialization, urbanization, population growth, and economic development. It is now well established that urban PM contains magnetic particles along with other air pollutants. The velocity and temporal variability of the deposition of such PM on tree leaves are subject to the pollution sources, climate, and local atmospheric conditions. Therefore, these variables have to be taken into account during a biomonitoring. This study presents a magnetic biomonitoring in the city of Queretaro. In the city’s metropolitan area, the most abundant and perennial tree species for biomonitoring is Ficus benjamina. For leaves of this species, the number of days needed for collection NDNC was measured, taking into account the meteorological conditions and the time at which they reached the saturation of airborne PM (pollutants). By means of sequential sampling, we identified that the minimum NDNC after a rainfall > 3 mm is 15 days. In such a period, total suspended particle TSP depositions reach its dynamic equilibrium. This behavior can be observed from measurements of specific magnetic susceptibility χ in Ficus benjamina samples and their comparison with TSP depositions collected with traditional Hi-Vol monitoring systems. After the NDNC calculation, a magnetic monitoring was performed with the biomonitor Ficus benjamina to evaluate the air quality at different sites in the metropolitan area every month for a period of 5 months. Values of χ ranged from 0.45 to 18.52 × 10−8m3kg−1. The species Ficus benjamina can be used as a biomonitor in the city of Queretaro only in seasons (winter-spring) with no or low rainfall. The species has the advantage of providing current PM information about a specific period of time.

The Yucatan state, Mexico, encloses a large karstic aquifer, which is confined near the coast. There are places where this confinement is fractured creating springs that discharge to wetlands or shallow lagoons, which are important because of the freshwater ecosystems that develop around them (locally known as Petenes), and because they provide a thermohaline equilibrium in these systems. Previous studies reported that during spring low tide, the spring becomes a sink, reversing the flow in the Peten channel connecting the lagoon to the spring. Potentially, this inversion of the flow can cause the intrusion of brackish – and sometimes hypersaline - water from the lagoon into the aquifer, which can also have ecological implications. The flow reversal was observed in two sampling campaigns and it occurred a total of 16 times. In the last sampling campaign, it was confirmed that the spring becomes a sink, with measured water velocities of about 0.37 m/s at the channel end close to the spring. Preliminary results suggest that the flow reversal is controlled by the discharge from the aquifer, the confinement of the aquifer, the geometry of the lagoon and the inlet channel, as well as the sea tides. A simple 1D analytical solution was used to explain this phenomenon, which describes the hydrodynamic interaction between the lagoon and the aquifer by solving the heat equation, which can be used to simulate flow in both systems, a confined aquifer and a highly frictional lagoon. Therefore, the same solution was used to simulate the gradients observed between the confined aquifer and the lagoon. The solution was implemented as a Python library using Fourier series, and has the advantage that it can be used with more general boundary conditions and finite length systems. Finally, we present coefficients that can be used to determine under which conditions the flow reverses at the lagoon.

Springs are common features on the Yucatán coast. They can discharge either under the sea (submarine) or inland in coastal lagoons and wetlands. Previous observations of a coastal lagoon located on the northern Yucatán Peninsula (La Carbonera) reported sea water intrusion on a spring that discharge on a coastal lagoon (lagoon tidal spring). The saltwater intrusion occurs when the tide is at its lower level, which is the opposite to what has been reported for submarine springs in the Yucatán Peninsula. In this study, the hydrodynamics of the spring is analyzed and the driving forces controlling the seawater intrusion are identified and discussed. Time series of water levels, salinity, and velocity measurements in the lagoon, the aquifer, and the spring are analyzed by means of tide component decomposition and cross-correlations analysis of the tide signals. Results show that the main driving forces causing the intrusion are the density differences and pressure head gradients, and the mechanisms influencing the driving forces driving those differences are the tides, the friction in the lagoon, and the confinement of the aquifer; other mechanisms are discussed to present a complete idea of the complexity of the interactions between the coastal aquifer, the coastal lagoons, and the sea.