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Oportunidad de aplicación de la metodología FRONT END LOADING en la expansión de gasoductos en el sureste mexicano: una evaluación

Opportunity to apply the front end loading methodology in the expansion of gas pipelines in the mexican southeast: an evaluation

Raúl Enrique Trejo Alvarado Luis Rolando Méndez Miguel (2023, [Artículo])

Con la finalidad de impulsar el desarrollo de la región sureste de México, la actual administración del gobierno federal se ha propuesto la ampliación de la red nacional de gasoductos hacia esa zona del país, con el fin de suministrar energía a los megaproyectos de la región. No obstante, estas obras presentan actualmente retrasos, evidenciando la necesidad de metodologías de gestión que permitan solucionar este problema de raíz. Una de las metodologías más prometedoras en esta materia es la front-end loading (FEL), ampliamente aplicada en el sector extractivo y energético. El propósito del articulo estriba en evaluar la posibilidad de aplicar la metodología FEL a los proyectos de expansión del Sistema Nacional de Gasoductos en el sureste mexicano.

To boost the development of the southeast region of Mexico, the current federal government administration has proposed the expansion of the national gas pipeline network to this area of the country, to supply energy to the region's mega-projects. However, these projects are currently experiencing delays, demonstrating the need for management methodologies to solve this problem at its root. One of the most promising methodologies in this area is front-end loading (FEL), which has been widely applied in the extractive and energy sector. The aim of this paper is to evaluate the possibility of applying the FEL methodology to the expansion projects of the National Gas Pipeline System in the southeastern México.

Gas natural Sector energético Front end loading (FEL) Evaluación de proyectos Sureste mexicano Natural gas Energy sector Project evaluation Mexican southeast INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS OTRAS ESPECIALIDADES TECNOLÓGICAS OTRAS OTRAS

Estado del arte sobre operación y mantenimiento de redes entubadas de riego

JUAN MANUEL ANGELES HERNANDEZ Mario Alberto Montiel Gutiérrez JOSE ANGEL GUILLEN GONZALEZ Ramon Lomeli Maria Dolores Olvera Salgado Arturo González Casillas (2011, [Documento de trabajo])

Con la finalidad de proporcionar una herramienta de consulta al personal técnico de las instituciones, especialmente de las organizaciones de usuarios que operan directamente la infraestructura de riego, en el presente trabajo se plantea la revisión del estado del arte sobre la operación y mantenimiento de las redes entubadas, en donde, en un documento maestro, se plasmarán los principales lineamientos que permitan hacer más eficiente el uso de esta tecnología para optimizar los recursos naturales, económicos y técnicos de las zonas de riego.

Riego Redes entubadas Operación y mantenimiento Informes de proyectos CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA

Entubamiento de la conducción del agua de riego del tramo San Alejo-Pilcaya y tecnificación del riego de la unidad de riego de Pilcaya, estado de Guerrero

Juan Manuel Angeles MAURO IÑIGUEZ COVARRUBIAS HELENE EMMI KARIN UNLAND WEISS (2008, [Documento de trabajo])

La Unidad de riego Pilcaya, está agrupada en una Sociedad de Aguas de Riego denominada “Flores – Jabalí“. La junta directiva de esta Sociedad hace la distribución del agua, misma que posee la concesión, consta de 429 socios con un total de 412 Acciones, en donde cada Acción comprende una superficie de 1.2 ha, por lo que esta Sociedad de Aguas de Riego representa una superficie total de 494.4 ha, misma que se considera es la superficie regada. Sin embargo, por cuestiones de rotación de cultivos, se tiene una superficie dominada con infraestructura de riego de 1,044.4 ha. El tipo de tenencia de la tierra es pequeña propiedad. La fuente de abastecimiento es uno de los manantiales que proviene de los deshielos del Volcán Nevado de Toluca, mismo que se conduce hasta la Unidad de Riego de Pilcaya, mediante un canal revestido del tramo que va desde la población de San Alejo, municipio de Ixtapan de la Sal, Estado de México, a la cabecera municipal de Pilcaya, Guerrero. Dentro de la zona de riego, se dispone de tres bordos que se utilizan para almacenar y regular el agua de riego. El propósito del entubamiento es dejar preparado para que en un futuro los usuarios puedan instalar sistemas de riego presurizados, sin necesidad de requerir equipo de bombeo.

Riego Redes entubadas Desarrollo tecnológico INGENIERÍA Y TECNOLOGÍA

Environmental Nanoparticles Reach Human Fetal Brains

LILIAN OFELIA CALDERON GARCIDUEÑAS ANGEL AUGUSTO PEREZ CALATAYUD ANGELICA GONZALEZ MACIEL RAFAEL REYNOSO ROBLES Héctor Gabriel Silva Pereyra Andrea Ramos Morales RICARDO TORRES JARDON Candelario de Jesús Soberanes Cerino Raúl Carrillo Esper JESÚS CARLOS BRIONES GARDUÑO Yazmin del Socorro Conde Gutiérrez (2022, [Artículo])

"Anthropogenic ultrafine particulate matter (UFPM) and industrial and natural nanoparticles (NPs) are ubiquitous. Normal term, preeclamptic, and postconceptional weeks(PCW) 8–15 human placentas and brains from polluted Mexican cities were analyzed by TEM and energy-dispersive X-ray spectroscopy. We documented NPs in maternal erythrocytes, early syncytiotrophoblast, Hofbauer cells, and fetal endothelium (ECs). Fetal ECs exhibited caveolar NP activity and widespread erythroblast contact. Brain ECs displayed micropodial extensions reaching luminal NP-loaded erythroblasts. Neurons and primitive glia displayed nuclear, organelle, and cytoplasmic NPs in both singles and conglomerates. Nanoscale Fe, Ti, and Al alloys, Hg, Cu, Ca, Sn, and Si were detected in placentas and fetal brains. Preeclamptic fetal blood NP vesicles are prospective neonate UFPM exposure biomarkers. NPs are reaching brain tissues at the early developmental PCW 8–15 stage, and NPs in maternal and fetal placental tissue compartments strongly suggests the placental barrier is not limiting the access of environmental NPs. Erythroblasts are the main early NP carriers to fetal tissues. The passage of UFPM/NPs from mothers to fetuses is documented and fingerprinting placental single particle composition could be useful for postnatal risk assessments. Fetal brain combustion and industrial NPs raise medical concerns about prenatal and postnatal health, including neurological and neurodegenerative lifelong consequences."

Environmental medicine Placental impairment Neurodevelopmental disorders Fetal brains Erythroblasts Preeclampsia Nanoparticles NPs extracellular vesicles Petrochemical pollution Villahermosa Tabasco BIOLOGÍA Y QUÍMICA QUÍMICA BIOQUÍMICA BIOQUÍMICA

Economics of crop residue management

Vijesh Krishna Maxwell Mkondiwa (2023, [Artículo])

More than five billion metric tons of agricultural residues are produced annually worldwide. Despite having multiple uses and significant potential to augment crop and livestock production, a large share of crop residues is burned, especially in Asian countries. This unsustainable practice causes tremendous air pollution and health hazards while restricting soil nutrient recycling. In this review, we examine the economic rationale for unsustainable residue management. The sustainability of residue utilization is determined by several economic factors, such as local demand for and quantity of residue production, development and dissemination of technologies to absorb excess residue, and market and policy instruments to internalize the social costs of residue burning. The intervention strategy to ensure sustainable residue management depends on public awareness of the private and societal costs of open residue burning.

Crop Biomass Residue Burning Environmental Effects CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CROPS BIOMASS RESIDUES ENVIRONMENTAL IMPACT CLIMATE CHANGE SMALLHOLDERS TECHNOLOGY ADOPTION

The input reduction principle of agroecology is wrong when it comes to mineral fertilizer use in sub-Saharan Africa

Gatien Falconnier Marc Corbeels Frédéric Baudron Antoine Couëdel leonard rusinamhodzi bernard vanlauwe Ken Giller (2023, [Artículo])

Can farmers in sub-Saharan Africa (SSA) boost crop yields and improve food availability without using more mineral fertilizer? This question has been at the center of lively debates among the civil society, policy-makers, and in academic editorials. Proponents of the “yes” answer have put forward the “input reduction” principle of agroecology, i.e. by relying on agrobiodiversity, recycling and better efficiency, agroecological practices such as the use of legumes and manure can increase crop productivity without the need for more mineral fertilizer. We reviewed decades of scientific literature on nutrient balances in SSA, biological nitrogen fixation of tropical legumes, manure production and use in smallholder farming systems, and the environmental impact of mineral fertilizer. Our analyses show that more mineral fertilizer is needed in SSA for five reasons: (i) the starting point in SSA is that agricultural production is “agroecological” by default, that is, very low mineral fertilizer use, widespread mixed crop-livestock systems and large crop diversity including legumes, but leading to poor soil fertility as a result of widespread soil nutrient mining, (ii) the nitrogen needs of crops cannot be adequately met solely through biological nitrogen fixation by legumes and recycling of animal manure, (iii) other nutrients like phosphorus and potassium need to be replaced continuously, (iv) mineral fertilizers, if used appropriately, cause little harm to the environment, and (v) reducing the use of mineral fertilizers would hamper productivity gains and contribute indirectly to agricultural expansion and to deforestation. Yet, the agroecological principles directly related to soil fertility—recycling, efficiency, diversity—remain key in improving soil health and nutrient-use efficiency, and are critical to sustaining crop productivity in the long run. We argue for a nuanced position that acknowledges the critical need for more mineral fertilizers in SSA, in combination with the use of agroecological practices and adequate policy support.

Manure Crop Yields Smallholder Farming Systems Environmental Hazards CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA BIOLOGICAL NITROGEN FIXATION LEGUMES NUTRIENT BALANCE SOIL FERTILITY AGROECOLOGY YIELD INCREASES LITERATURE REVIEWS