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Selecciona los temas de tu interés y recibe en tu correo las publicaciones más actuales
Dagne Wegary Gissa Amsal Tarekegne (2023, [Artículo])
Three-Way Crosses Single-Crosses Better and Mid-Parent Heterosis CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CROSS-BREEDING HYBRIDS HETEROSIS MAIZE
Briseida Corzo Rivera Gabriel Castañeda Nolasco (2023, [Artículo, Artículo])
Access to water is a common struggle of the communities in the state of Chiapas, with the effects of urban expansion these struggles increase and with them the challenges that these populations already face, having a greater impact on the rural environment. The struggles to satisfy this basic need are a factor that has triggered processes that promote community participation. Based on a qualitative analysis, this paper compares two existing forms of participation in the rural communities of the Metropolitan Area of Tuxtla Gutierrez that allow the population to manage actions to improve their quality of life. The objective is to analyze how these processes promote or restrict the empowerment of the community and allow progress, not only in the population's access to water, but also in the construction of the right to the city. From the urban-rural linkages, the right to the city is discussed beyond the city, addressing other territories. The study identifies factors that show changes in the participation of the populations and strengthen the community, as well as factors in the relationships of the community and of the community with other actors that limit the scope of the processes.
Participation Right to the city Urban-rural linkages Access to water participación, derecho a la ciudad, vínculos urbano-rurales, acceso al agua. CIENCIAS SOCIALES CIENCIAS SOCIALES
Esther Imelda Ponce García (2023, [Tesis de maestría])
"Las enfermedades causadas por bacterias del género Vibrio en el cultivo de camarón son de gran importancia debido a su impacto negativo en la industria acuícola. Estas bacterias pueden causar diversas enfermedades en camarones, como la necrosis hepatopancreática aguda (AHPND). La fagoterapia es una alternativa para el biocontrol de estas bacterias patógenas que presenta importantes ventajas, como la alta especificidad a sus huéspedes, la replicación en el sitio de infección, y la capacidad de infectar a bacterias resistentes a antibióticos. Sin embargo, la estabilidad de los fagos en el sistema de cultivo es una preocupación latente, ya que los fagos presentan una estabilidad limitada en solución y experimentan una caída significativa en el título de fagos durante el procesamiento y almacenamiento. El método de encapsulación de bacteriófagos, un área que aún no se estudia del todo, se presenta como una potencial alternativa para atender esta problemática. En el presente estudio se evaluó la eficacia terapéutica de un cóctel de bacteriófagos (vB_Vp_PvVp05, vB_Vp_PvVp07 y vB_Vp_PvVp11), encapsulados en alginato de sodio comercial y de mediana viscosidad, pectina, carboxilmetilcelulosa, liposomas y liofilizado en pectina como agente de biocontrol de Vibrio parahaemolyticus para su uso en terapias fagicas pasiva y activa. Se observó que el encapsulado en alginato de sodio de mediana viscosidad presentó la mayor liberación de fagos activos y al momento de ser incorporado a alimento para camarón y horneados a 80 – 100°C, se mantuvo una concentración de 1.3 x105 UFP/g después de 100 días de almacenamiento. Para la evaluación de las terapias pasiva y activa se realizó una infección experimental en juveniles de Penaeus vannamei para conocer la efectividad de los encapsulados, utilizando para la terapia pasiva la cepa Vp M0904 y para la activa la cepa Vp M0605. El experimento de terapia pasiva mostró una mortalidad del 80.6% en los camarones a las 48 hpi (p > 0.05) y una concentración de 5 x102 UFC/mL de Vibrio spp. no fermentativos en TCBS. En el caso de la terapia activa no se presentó mortalidades, pero hubo una disminución de la concentración de Vibrio spp. no fermentativos en TCBS con 5.56 x101 UFC/mL a las 48 hpi (p < 0.05) y aumentó la densidad de vibriófagos en 1.4 x102 UFP/mL en el agua de los acuarios (p < 0.05)..."
"Diseases caused by bacteria of the Vibrio genus in shrimp farming are of great importance due to their negative impact on the aquaculture industry. These bacteria can cause various diseases in shrimp, such as acute hepatopancreatic necrosis disease (AHPND). Phage therapy is an alternative for the biocontrol of these pathogenic bacteria, offering significant advantages, including high specificity to their hosts, replication at the infection site, and the ability to infect antibiotic-resistant bacteria. However, the stability of phages in the farming system is a persistent concern, as phages have limited stability in solution and undergo a significant drop in phage titer during processing and storage. The method of bacteriophage encapsulation, an area that is not yet fully explored, emerges as a potential alternative to address this issue. In this study, the therapeutic efficacy of a cocktail of bacteriophages (vB_Vp_PvVp05, vB_Vp_PvVp07, and vB_Vp_PvVp11), encapsulated in commercial medium-viscosity sodium alginate, pectin, carboxymethylcellulose, liposomes, and lyophilized pectin, was evaluated as a biocontrol agent against Vibrio parahaemolyticus for use in passive and active phage therapies. It was observed that encapsulation in medium-viscosity sodium alginate showed the highest release of active phages, maintaining a concentration of 1.3 x 105 PFU/g after 100 days of storage when incorporated into shrimp feed and baked at 80–100°C.For the evaluation of passive and active therapies, an experimental infection was conducted on Penaeus vannamei juveniles to assess the effectiveness of the encapsulated phages. The passive therapy experiment showed a mortality rate of 80.6% in shrimp at 48 hpi (p > 0.05) and a concentration of 5 x 102 CFU/mL of non-fermentative Vibrio spp. on TCBS agar. In the case of active therapy, no mortalities were observed, but there was a decrease in the concentration of non-fermentative Vibrio sp. on TCBS agar to 5.56 x 101 CFU/mL at 48 hpi (p < 0.05), and the density of vibriophages increased to 1.4 x 102 PFU/mL in the aquarium water (p < 0.05). It was determined that passive therapy offered no advantage for the control of Vibrio parahaemolyticus, unlike active therapy, which proved to be effective in controlling this bacterium."
vibriófagos, encapsulado, Penaeus vannamei, terapia activa, terapia pasiva vibriophages, encapsulated, active therapy, passive therapy BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA MICROBIOLOGÍA BACTERIÓFAGOS BACTERIÓFAGOS
Jose Crossa Osval Antonio Montesinos-Lopez Morten Lillemo (2024, [Artículo])
Multispectral Imaging Grain Yield Genomic Prediction CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA GRAIN YIELDS HIGH-THROUGHPUT PHENOTYPING SPRING WHEAT
Satellite imagery for high-throughput phenotyping in breeding plots
Francisco Pinto Mainassara Zaman-Allah Matthew Paul Reynolds Urs Schulthess (2023, [Artículo])
Optimized Soil Adjusted Vegetation Index CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA HIGH-THROUGHPUT PHENOTYPING SATELLITES WHEAT MAIZE BREEDING NORMALIZED DIFFERENCE VEGETATION INDEX
Gerald Blasch David Hodson Francelino Rodrigues (2023, [Artículo])
Very high (spatial and temporal) resolution satellite (VHRS) and high-resolution unmanned aerial vehicle (UAV) imagery provides the opportunity to develop new crop disease detection methods at early growth stages with utility for early warning systems. The capability of multispectral UAV, SkySat and Pleiades imagery as a high throughput phenotyping (HTP) and rapid disease detection tool for wheat rusts is assessed. In a randomized trial with and without fungicide control, six bread wheat varieties with differing rust resistance were monitored using UAV and VHRS. In total, 18 spectral features served as predictors for stem and yellow rust disease progression and associated yield loss. Several spectral features demonstrated strong predictive power for the detection of combined wheat rust diseases and the estimation of varieties’ response to disease stress and grain yield. Visible spectral (VIS) bands (Green, Red) were more useful at booting, shifting to VIS–NIR (near-infrared) vegetation indices (e.g., NDVI, RVI) at heading. The top-performing spectral features for disease progression and grain yield were the Red band and UAV-derived RVI and NDVI. Our findings provide valuable insight into the upscaling capability of multispectral sensors for disease detection, demonstrating the possibility of upscaling disease detection from plot to regional scales at early growth stages.
Very High Resolution Imagery Disease Detection Methods Early Growth Stages CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA UNMANNED AERIAL VEHICLES STEM RUST PHENOTYPING HIGH-THROUGHPUT PHENOTYPING WHEAT
In-service weld repair by direct deposition: numerical simulation and experimental validation
LUIS DANTE MELENDEZ MORALES Jose Jorge Ruiz Mondragon MARICRUZ HERNANDEZ HERNANDEZ (2023, [Artículo])
In-Service Welding is a technological process for which interconnection and repair of pipelines can be made while they are in operation, before making it two main risks need to be assessed: hydrogen cracking and burn-through. Current simulations and validations assess these risks independently, but due to its interdependence these risks need to be assessed in conjunction. A repair method not normally used, but with high potential due to its simplicity and versatility is the direct deposition of weld. In the present research, a fluid-thermo-mechanical coupled simulation and validation were done of an in-service welding repair by direct deposition on a flowing pressurized pipe having an internal defect. The results demonstrated the effectiveness of using this repair method to restore the mechanical strength of pipelines. Surface, sub-surface, and volumetric non-destructive examinations evidenced no cracking immediately to finish the repair and delayed. Temperature tendency curves showed good approximations having a maximum difference of 5.09 % between numerical and experimental. Perimeter deformation along the pipe length between numerical and experimental results displayed a similar behaviour with a significant difference in the numerical values attributed to the lack of input data for weld properties. The structural analysis performed in this study used the approach of the risk of burn-through under internal pressure determined by the occurrence of localized radial bulging. Numerical results indicated no relevant plastic strain occurs. Is strongly recommended that thermal analysis assessments using the actual defect morphology would be performed, not only considering the remaining thickness of the pipe.
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.
Acknowledgements: The authors gratefully acknowledge to Petropipe de Mexico for technical support, materials and equipment needed for the experimental validation. The first author wants also to acknowledge to CONAHCYT (Consejo Nacional de Humanidades, Ciencias y Tecnologías), for the post-graduate scholarship received.
In-service welding Burn-through Hydrogen cracking Weld repair INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS OTRAS ESPECIALIDADES TECNOLÓGICAS OTRAS OTRAS
LUIS DANTE MELENDEZ MORALES (2023, [Tesis de doctorado])
El transporte de hidrocarburos por ductos enterrados es la forma más segura, confiable y económica para su suministro, estos pueden extenderse grandes longitudes territoriales e inclusive atravesar países con tal de satisfacer la demanda energética. No obstante, los ductos pueden sufrir daños provocados por el ambiente, su operación o bien provocados por terceros, siendo necesario que sean intervenidos reemplazando las secciones dañadas. Las regulaciones nacionales y tratados internacionales desalientan la liberación de grandes cantidades de gas natural a la atmósfera, por demás de que un paro de suministro conlleva a desabasto energético, multas y a costosas operaciones asociadas con la rehabilitación del ducto, forzando a soldar envolventes y accesorios sin detener la operación de los ductos, esto se conoce como “soldadura en servicio”. La soldadura en servicio es un proceso tecnológico, por el cual se puede efectuar la interconexión y la reparación de ductos mientras están en operación, previo a realizar estas actividades, se requiere que dos riesgos sean evaluados: agrietamiento por hidrógeno y quemada pasante. Las simulaciones actuales y validaciones evalúan estos riesgos de forma independiente, pero debido a su interdependencia estos riesgos deben evaluarse en conjunto. Un método de reparación que no es normalmente empleado, pero con un alto potencial debido a su simplicidad y versatilidad, es la deposición directa de soldadura. En la presente investigación, se realizó una simulación numérica fluido-termo-mecánica acoplada con validación experimental, de la reparación de un tubo con flujo presurizado conteniendo un defecto interno por la deposición directa de soldadura. Por medio de la cual, es posible predecir el comportamiento estructural del ducto mientras se realiza la reparación.
La simulación numérica se efectuó con el apoyo del software ANSYS versión académica 22R2, siendo esta una herramienta de última generación capaz de contribuir en la predicción de mecanismos complejos como lo es la soldadura en servicio, incrementando con ello la seguridad y confiabilidad de estas operaciones. Cabe hacer mención, que la regulación nacional prohíbe la reparación de defectos internos por la deposición directa de soldadura, esto se debe principalmente a la falta de investigaciones validadas que respalden su viabilidad. Los resultados demostraron la efectividad de emplear este método de reparación para restaurar la resistencia mecánica de los ductos. Las inspecciones por pruebas no destructivas superficiales, subsuperficiales y volumétricas, evidenciaron que no ocurrió agrietamiento inmediatamente al finalizar la reparación y retardada (posterior a por lo menos 12 horas después de haberse finalizada la reparación, tiempo suficiente para permitir la difusión de hidrógeno atómico a hidrógeno molecular). Las curvas de tendencia de temperatura mostraron buena aproximación teniéndose una diferencia máxima de 5.09% entre los resultados numéricos y experimental. Los resultados numéricos y experimentales de la deformación perimetral a lo largo de la longitud de la tubería mostraron un comportamiento similar con una diferencia significativa del 17.7% entre los valores numéricos atribuidos a la falta de información de entrada para las propiedades de la soldadura. El análisis estructural efectuado en este estudio emplea la estimación del riesgo de quemada pasante bajo presión interna, determinado por la ocurrencia de abultamiento radial localizado. Los resultados numéricos indican que no ocurre deformación plástica relevante. Se hace una fuerte recomendación para que las evaluaciones de análisis térmico empleen la morfología actual del defecto y no solo consideren el espesor remanente del tubo. De acuerdo con la revisión bibliográfica realizada y recientemente publicada, este tipo de simulación numérica acoplada con validación experimental de la reparación de ductos en servicio por deposición directa de soldadura para la reparación de defectos internos contemplando la prevención de quemada pasante y agrietamiento por hidrógeno no ha sido realizada con anterioridad.
Hydrocarbon transportation by buried pipelines is the safest, most reliable, and economical way for its supply; these can extend long territorial distances and even cross countries with the purpose of satisfying the energy demand. However, the pipelines can suffer damages caused by their environment, their operation, or provoked by third parties, making necessary interventions to replace the damaged sections. National regulations and international agreements discourage the release of large quantities of natural gas into the atmosphere; moreover, a stop in its supply entails an energetic shortage, fines, and expensive operations associated with the pipeline rehabilitation, forcing to weld sleeves and fittings without stop the pipeline operation, this is known as “In-Service Welding”. In-Service welding is a technological process for which interconnection and repair of pipelines can be made while they are in operation; before making it, two main risks need to be assessed: hydrogen cracking and burn-through. Current simulations and validations assess these risks independently, but due to their interdependence, these risks need to be assessed in conjunction. A repair method not normally used but with high potential due to its simplicity and versatility is the direct deposition of the weld. In the present research, a fluid-thermo-mechanical coupled numerical simulation with experimental validation was done of a repair on a pipe with pressurized flow having an internal defect by direct deposition of the weld. It is possible predict the structural behavior of a pipeline while the reparation is performed.
The numerical simulation was done with the support of ANSYS software academic version 22R2, the latest generation tool able to contribute to the prediction of complex mechanisms, as is in-service welding, increasing the security and confidence of these operations. It is worth mentioning that national regulation forbids the reparation of internal defects for direct deposition of the weld; the main reason is the lack of validated investigations supporting its viability. The results demonstrated the effectiveness of using this repair method to restore the mechanical strength of pipelines. Surface, sub-surface, and volumetric non-destructive inspections evidenced no cracking immediately to finish the repair and delayed (after at least 12 hours of having finished the repair, time enough to allow the hydrogen diffusion from atomic hydrogen to molecular hydrogen). Temperature tendency curves showed good approximations, having a maximum difference of 5.09 % between numerical and experimental. Perimeter deformation along the pipe length between numerical and experimental results displayed a similar behavior with a significant difference of 17.7% against numerical values attributed to the lack of input data for weld properties. The structural analysis performed in this study used the approach of the risk of burn-through under internal pressure determined by the occurrence of localized radial bulging. Numerical results indicated no relevant plastic strain occurs. It is strongly recommended that thermal analysis assessments using the actual defect morphology be performed, not only considering the remaining thickness of the pipe. According to the bibliographic revision performed and recently published, this kind of coupled numerical simulation of in-service repair or pipelines by direct deposition for repairing internal defects considering the prevention of burn-through and hydrogen cracking has not been done.
Ducto Soldadura en servicio Quemada pasante Agrietamiento por hidrógeno Reparación de soldadura Simulación numérica Pipeline In-service welding Burn-through Hydrogen cracking Weld repair Numerical simulation INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS OTRAS ESPECIALIDADES TECNOLÓGICAS OTRAS ESPECIALIDADES TECNOLÓGICAS
MARKUS SEBASTIAN GROSS (2016, [Artículo])
In previous work, the authors demonstrated how data from climate simulations can be utilized to estimate regional wind power densities. In particular, it was shown that the quality of wind power densities, estimated from the UPSCALE global dataset in offshore regions of Mexico, compared well with regional high resolution studies. Additionally, a link between surface temperature and moist air density in the estimates was presented. UPSCALE is an acronym for UK on PRACE (the Partnership for Advanced Computing in Europe)-weather-resolving Simulations of Climate for globAL Environmental risk. The UPSCALE experiment was performed in 2012 by NCAS (National Centre for Atmospheric Science)- Climate, at the University of Reading and the UK Met Office Hadley Centre. The study included a 25.6-year, five-member ensemble simulation of the HadGEM3 global atmosphere, at 25km resolution for present climate conditions. The initial conditions for the ensemble runs were taken from consecutive days of a test configuration. In the present paper, the emphasis is placed on the single climate run for a potential future climate scenario in the UPSCALE experiment dataset, using the Representation Concentrations Pathways (RCP) 8.5 climate change scenario. Firstly, some tests were performed to ensure that the results using only one instantiation of the current climate dataset are as robust as possible within the constraints of the available data. In order to achieve this, an artificial time series over a longer sampling period was created. Then, it was shown that these longer time series provided almost the same results than the short ones, thus leading to the argument that the short time series is sufficient to capture the climate. Finally, with the confidence that one instantiation is sufficient, the future climate dataset was analysed to provide, for the first time, a projection of future changes in wind power resources using the UPSCALE dataset. It is hoped that this, in turn, will provide some guidance for wind power developers and policy makers to prepare and adapt for climate change impacts on wind energy production. Although offshore locations around Mexico were used as a case study, the dataset is global and hence the methodology presented can be readily applied at any desired location. © Copyright 2016 Gross, Magar. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reprod
atmosphere, climate change, Europe, Mexico, sampling, time series analysis, university, weather, wind power, climate, risk, theoretical model, wind, Climate, Models, Theoretical, Risk, Wind CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO OCEANOGRAFÍA OCEANOGRAFÍA
Research for development approaches in mixed crop-livestock systems of the Ethiopian highlands
Million Gebreyes James Hammond Lulseged Tamene Getachew Agegnehu Rabe Yahaya Anthony Whitbread (2023, [Artículo])
This study presents processes and success stories that emerged from Africa RISING's Research for Development project in the Ethiopian Highlands. The project has tested a combination of participatory tools at multiple levels, with systems thinking and concern for sustainable and diversified livelihoods. Bottom-up approaches guided the selection of technological interventions that could address the priority farming system challenges of the communities, leading to higher uptake levels and increased impact. Joint learning, appropriate technology selection, and the creation of an enabling environment such as the formation of farmer research groups, the establishment of innovation platforms, and capacity development for institutional and technical innovations were key to this study. The study concludes by identifying key lessons that focus more on matching innovations to community needs and geographies, systems orientation/integration of innovations, stepwise approaches to enhance the adoption of innovations, documenting farmers' capacity to modify innovations, building successful partnerships, and facilitating wider scaling of innovations for future implementation of agricultural research for development projects.
Action Research Systems Thinking CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA INNOVATION PARTNERSHIPS SCALING UP INTEGRATED CROP-LIVESTOCK SYSTEMS