Computational Fluid Dynamics Achievements Applied to Optimal Crop Production in a Greenhouse

Computational fluid dynamics has been successfully used in protected agriculture to simulate greenhouse weather as physical processes. The variables involved are velocity, wind direction related to either absolute or relative humidity, temperature as well as deficit vapor pressure, and carbon dioxide, among others. The research evolution is changing from the traditional validation of new designs and management to testing efficient production with less environmental pollution. This work points out this kind of assessment based on the physical principles of conservation of mass, momentum, and energy. Constitutive relationships like Darcy-Forchheimer porosity model in the momentum equation as well as the geometry and physical properties of the materials involved are needed to fulfill the particular solutions of temperature, wind, and humidity. This chapter is enhanced by the effect of solar radiation in more processes like crop transpiration with dynamical meshes and condensation

Correlation sow, piglet and personnel responsible at the design of a farrowing crate for sow

ABSTRACT In housing for sows in a farrowing pen must meet the environmental requirements of the sow, the piglet and personnel responsible. Their daily activities require compliance with thermal, physical and social factors that are closely related to their welfare. Evaluation of 200 models used in the main pig producing countries to define world trends farrowing, their technical and economic arguments that fundamental. Coexistence sow, piglet and human, required to provide a temperature distribution that meets the biological requirements of every living entity and generate comfort, technical argument that explains why traditional farrowing crates that restrict the movement of the sow to protect the piglets are by discontinuing use. This work show the design of a farrowing crate as a commercial alternative to Mexico, which meets the 30 parameters defined, privileges the senses of touch, taste, smell, sight and hearing of the sow as generators of comfort, the footprint of his hooves and their points of contact with floors and express their respect by natural movements, when lie down, get up, eat and exercise. The five met manufactured prototypes expected in each of the four test runs expectations. With litter average 12 piglets, the average mortality rate in the twenty test scores is 5.3% after 3 days and 4.8% after 15 days old piglets. Swine farmers made following recommendations to help reduce the mortality rate. 1 show the economic benefits involved stress reduction in the sow. 2. Attend the timely and individual to each sow in childbirth. 3. Promote environmental enrichment variables that must be implemented in the Farrowing crate. 4. Provide the necessary room temperature for piglets and sows

La eficiencia en el uso del agua en la agricultura controlada

Muchas regiones del mundo han alcanzado el límite de aprovechamiento del agua, lo que las ha llevado a sobreexplotar los recursos hidráulicos superficiales y subterráneos, creando un impacto negativo en el ambiente. En los países en los que se depende del agua subterránea para el riego, como es el caso de México, el exceso de extracción está provocando que los niveles freáticos de agua dulce estén descendiendo a un ritmo muy alarmante. Aunado a lo anterior, el 77% del agua concesionada en México es utilizada en la agricultura; por tal razón, es urgente incrementar la eficiencia en el uso del agua en este sector. Este trabajo representa una breve revisión sobre las técnicas modernas de producción para incrementar la eficiencia del uso del agua, tales como el control ambiental en los invernaderos, sistemas hidropónicos de circuito semicerrado y cerrado, y los invernaderos semicerrados

Potential use of water saved with technification of gravity irrigation in non-agricultural sectors

Objective: Conceptually analyze the potential use of water that the technification of gravity irrigation allows to save and generate alternatives of use according to the extrapolation of volumes, both in the same agricultural sector, or outside it. Design/methodology/approach: The Technified Gravity Irrigation Program (RIGRAT) will be evaluated. By measuring the volumes of irrigation used in the Irrigation Districts (DR) 075 Rio Fuerte, 076 Valle del Carrizo and 063 Guasave, Sinaloa, during the 2015-2018 agricultural cycles. The measured and statistical data are integrated for the analysis of volumes saved by the program and its national statistical projection. Results: In 6,114.5 ha under technification of the RIGRAT program in DR 075, the volume saved was 2,401.02 thousand m3 (2.4 hm3). The volume of water saved on that surface represents 10% of the water used by the industrial sector of Sinaloa. It is inferred that the modernization of the DR075 Rio Fuerte in the planted area of 289,780 ha, would imply a saving of 40% of the water that can be used in urban areas of Sinaloa. In the same agricultural sector, it would be possible to save a volume of 187 thousand m3, which means 6.4% of the water used by the irrigation district at plot level. Limitations on study/implications: Current regulations do not allow the transfer of water volume in its different uses, with the aim of optimizing the value of water. Findings/conclusions: With actions implemented in the RIGRAT program, it represents that achieving water savings at the farm level would have a great impact, since agriculture is the main consumer of water and there could be volumes saved to be used in other sectors.  Objective: To analyze conceptually the potential use of water that the technification of gravity irrigation allows in saving and generating alternatives of use according to the extrapolation of volumes, both in the agricultural sector or outside of it. Design/methodology/approach: The Modernized Gravity Irrigation Program (RIGRAT) will be evaluated, by measuring the volumes of irrigation used in the Irrigation Districts (ID) 075 Río Fuerte, 076 Valle del Carrizo, and 063 Guasave, Sinaloa, during the 2015-2018 agricultural cycles. The measured and statistical data are integrated for the analysis of volumes saved by the program and its national statistical projection. Results: The volume saved in the ID 075 was 2,401.02 thousand m3 (2.4 hm3) in 6,114.5 ha under technification of the RIGRAT program. The volume of water saved on that surface represents 10% of the water used by the industrial sector of Sinaloa. It is inferred that the modernization of the ID 075 Río Fuerte in the planted area of 289,780 ha, would imply a saving of 40% of the water that can be used in urban areas of Sinaloa. In the same agricultural sector, it would be possible to save a volume of 187 thousand m3, which represents 6.4% of the water used by the irrigation district at plot level. Limitations on study/implications: Current regulations do not allow the transfer of water volume in its different uses, with the aim of optimizing the value of water. Findings/conclusions: With actions implemented in the RIGRAT program, water saving is achieved at the farm level and there would be a great impact, since agriculture is the main consumer of water and there could be volumes saved to be used in other sectors

Advancing in Schaaf-Yang syndrome pathophysiology: from bedside to subcellular analyses of truncated MAGEL2

Background Schaaf-Yang syndrome (SYS) is caused by truncating mutations in MAGEL2, mapping to the Prader-Willi region (15q11-q13), with an observed phenotype partially overlapping that of Prader-Willi syndrome. MAGEL2 plays a role in retrograde transport and protein recycling regulation. Our aim is to contribute to the characterisation of SYS pathophysiology at clinical, genetic and molecular levels. Methods We performed an extensive phenotypic and mutational revision of previously reported patients with SYS. We analysed the secretion levels of amyloid-β 1-40 peptide (Aβ1-40) and performed targeted metabolomic and transcriptomic profiles in fibroblasts of patients with SYS (n=7) compared with controls (n=11). We also transfected cell lines with vectors encoding wild- type (WT) or mutated MAGEL2 to assess stability and subcellular localisation of the truncated protein. Results Functional studies show significantly decreased levels of secreted Aβ1-40 and intracellular glutamine in SYS fibroblasts compared with WT. We also identified 132 differentially expressed genes, including non-coding RNAs (ncRNAs) such as HOTAIR, and many of them related to developmental processes and mitotic mechanisms. The truncated form of MAGEL2 displayed a stability similar to the WT but it was significantly switched to the nucleus, compared with a mainly cytoplasmic distribution of the WT MAGEL2. Based on the updated knowledge, we offer guidelines for the clinical management of patients with SYS. Conclusion A truncated MAGEL2 protein is stable and localises mainly in the nucleus, where it might exert a pathogenic neomorphic effect. Aβ1-40 secretion levels and HOTAIR mRNA levels might be promising biomarkers for SYS. Our findings may improve SYS understanding and clinical management

Investigación en matemáticas, economía y ciencias sociales

El resultado de este libro que reune inquietudes académicas en torno a temas tan estudiados como los que están alrededor del maíz, del frijol o del café; y tan contemporáneos como las aplicaciones concretas de las ciencias ya citadas, al estudio de la adopción del comercio electrónico en empresas del sector agroindustrial o, el caso de la generación de biogas o energía eléctrica por medio de biodigestores. Al editar este texto e incorporarlo a la bibliografía de los temas de referencia, se enriquecen opciones de consulta para los estudiosos de esos temas en general; pero también para interesados en aspectos tan específicos como la cadena de suministro del mercado hortofrutícola en Texcoco

A theoretical study of gas flow in porous media with a spherical source

Gas flow behavior from a spherical source is explored by using linear and nonlinear models, not only in terms of pressure but also in terms of flux. The approach considers dimensionless parameters scaling both radius and time. Specific observations are made for large, moderate, and small time conditions. At large time, the nonlinear model becomes a linear ordinary differential equation with pressure solution independent of the material. However, for moderate and small scaled times this is not the case. The nonlinear model must be solved by using either linear approximations, semi-analytical, or numerical procedures. This model is nonlinear in the primary variable (pressure). However, appropriate mathematical manipulations allow one to change the nonlinearity into a single coefficient, depending on pressure. Focusing on the effects of this coefficient, the nonlinear solution can be confined between two linear solutions obtained by using atmospheric and boundary pressures. Appendix A is an exploration of the errors arising between the nonlinear solution and these two solutions. In Appendix B, a nonlinear model is used to find solutions for large, moderate, and small times. For large time, the case corresponds to the steady state case, and coincides with the solution presented in Appendix A. For moderate and small times the quasi-analytical approximation and the asymptotic solutions of linear and quadratic normalizations of pressure are presented. In Appendix C, simulations of gas flows in linear and nonlinear situations are made. The problem is to determine the change of air pressure in a tank when it is connected to a spherical cavity embedded in a porous medium. These changes in pressure occur when the air moves through the porous media, either for gas extraction or air injection. Both linear and nonlinear analyses require calculations of the pressure and the mass in the tank when the initial and boundary conditions change with time. For each case, gas extraction or air injection, the differences between the linear and the nonlinear models are examined to determine the suitability of the linear model

Methodology for estimation of integrated evapotranspiration and canal capacity in an irrigation zone

La capacidad de la red de canales en un sistema de riego depende de satisfacer la demanda hídrica máxima de los cultivos. Los métodos para determinar la capacidad del canal requieren de la estimación de la variable agronómica: evapotranspiración de los cultivos. En grandes áreas de riego, con un padrón diversificado de cultivos, diferentes fechas de siembra y varios ciclos agrícolas no existe un procedimiento integrado para estimar esta variable agronómica, lo cual genera incertidumbre al ser requerida en los métodos. En este trabajo se desarrolla una propuesta para estimar dicha variable para grandes zonas de riego. La propuesta inicia con el cálculo de la evapotranspiración de los cultivos por fecha de siembra, y termina con la obtención de una curva general integral para un año agrícola, encontrándose la variable evapotranspiración de una zona de riego (ETzr). Esta metodología se aplicó para el canal principal del módulo de riego Santa Rosa, Distrito de Riego 075, Sinaloa, México en que la ETzr resultó de 4,1 mm d-1. Por los resultados se concluye la veracidad de la propuesta en determinar la evapotranspiración para el cálculo en la capacidad del canal.Capacity of irrigation networks needs to satisfy peak crop water demands. The methods to size canal capacity require the estimation of an agronomic variable: crop evapotranspiration. There is not an integrated procedure to estimate crop evapotranspiration for large irrigation zones with a diversified crop pattern, different planting dates, and several crop seasons. Not having this procedure generates uncertainty in methods for canal capacity estimations. This paper presents a methodological proposal to estimate the ET variable for large irrigation zones. The procedure starts with calculating the ET for each planting date per crop and season. Next, it integrates a general ET curve for the water year that finds the evapotranspiration for the irrigation zone (ETzr). The methodology was applied to size the main canal that supplies the “Santa Rosa" Water Irrigation Association in the 075 Irrigation District located in the state of Sinaloa, Mexico. A value of 4.1 mm d-1 was estimated for ETzr. The results indicate the proposed method’s accuracy to estimate the ET variable to size irrigation canals.Fil: Íñiguez-Covarrubias, Mauro. Instituto Mexicano de Tecnología del Agua (Morelos, México).Fil: Ojeda-Bustamante, Waldo. Instituto Mexicano de Tecnología del Agua (Morelos, México).Fil: Rojano-Aguilar, Abraham. Universidad Autónoma Chapingo (México