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Banco de agua

GUSTAVO ARMANDO ORTIZ RENDON RAMON LOPEZ HERNANDEZ (2004, [Libro])

Se propone el diseño y reglas de funcionamiento de un banco de agua en México, que facilite las transacciones de agua entre usuarios y que, en concordancia con la legislación vigente, ayude a reducir la presión de la demanda de agua y libere volúmenes de agua concesionada para lograr fines ambientales específicos, dentro del contexto de la realidad económica, politica, social y ambiental del país.

Administración del agua Política hídrica Tarifas Factores socioeconómicos Legislación ambiental Bancos de agua Cuenca Lerma-Chapala CIENCIAS SOCIALES

Training Manual for Two-wheel tractor and ancillary equipment for operators, service providers, extension experts and workshop owners

Rabe Yahaya (2022, [Libro])

Mechanization is a term used to describe tools, implements and machinery applied to improve the productivity of farm land and labour force, including crop processing after harvest. Mechanization covers broadly the entire process of on and off farm operations and mechanization may use either human, animal or motorized power, or a combination of these. In practice, therefore, it involves the provision and use of all forms of power sources and mechanical assistance to agriculture, from simple hand tools to draught animal power and to motorized power technologies. In Ethiopia, smallholder farming experiences high drudgery at all stages of crop husbandry and post-harvest processing. Field operations are performed using human and animal power (Mrema et al., 2008). Smallholder farmers without animal power use a lot of human power on crop husbandry and harvesting operations (Daum et al., 2020). Postharvest threshing and shelling are performed using human power but, in some countries like Ethiopia, farmers use livestock (cattle, donkeys and horses) for wheat, barley and teff threshing (Mohammed and Tadesse, 2018). The use of tractor power is low in Ethiopia and the government aims to increase farm power available to Ethiopian farmers 10 folds (from the current 0.1 Kw ha-1 to 1 kW ha-1 ) by 2025, with at least half of this power is derived from fossil fuel and electric engines. The government of Ethiopia aims to increase farm power using two-wheel tractors on smallholder farms in addition to four-wheel tractors that are already in use. Two-wheel tractors are sources of power designed to perform most field operations. Due to the size of two-wheel tractors, they have become an economic alternative for smallholder farming. In addition, twowheel tractors are also more productive than animal traction and they require less time for attendance and preparation, giving the individual farmer more independence and contact with modern technology. Also, due to their simple design, local manufacturing of two-wheel tractors has been implemented in several countries successfully, increasing employment opportunities in the process.

CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA FARM EQUIPMENT TRACTORS TRAINING SMALLHOLDERS

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