Water and agriculture

This chapter shows the strong links between water, agriculture and the economy in Latin America and Caribbean (LAC). Both green and blue water are vital for LAC's economies and for its food security. Awareness of LAC's virtual water trade volumes and water footprints alone will not solve the local or global water problems. However, the awareness gained increases the likelihood that optimized water allocation decisions, which consider the hydrological and economical aspects of water resources, are made. • Agriculture is a significant economic sector for many LAC countries with some being major world players in the agricultural commodities world markets, such is the case for Brazil and Argentina who contribute to 13% of the global green water export. At the micro level, agriculture still plays a significant role for the food security of the population. • The consumptive water use of agricultural production was on average 1,057Gm 3 / yr for the period 1996–2005; of which, 95% corresponds to the green water footprint, whereas 5% refers to the blue component. This indicates that LAC relies heavily on green water for agricultural production, i.e. rain-fed agriculture. • Maize is a fundamental crop in Argentina, Brazil, Chile, Mexico and Peru, representing 15% of the total agricultural blue and green water footprint (773,408hm 3 /yr) and contributing to 35% of the agricultural nitrogen pollution, estimated as grey water footprint, in Argentina, Brazil, Chile, Colombia, Mexico and Peru. Only in Mexico, maize contributes 60% of the agricultural grey water footprint. • Grazing represents 24% of the total green water footprint of agriculture in these countries. The blue water consumption by the animal water supply is very significant in Argentina, Brazil, Chile, Mexico and Peru, which amounts to 13% (38,825hm 3 /yr) of the total consumption

Influencia de la geometría de entrada en tomas sumergidas sobre la sumersión crítica para la formación de vórtices que arrastran aire

RESUMENSe realizó un estudio experimental para estudiar la influencia de la geometría de una toma horizontal sumergida en la formación de vórtices de superficie libre que arrastran aire. Se ensayaron dos tipos de perfiles de ingreso a la toma: perfil acampanado y de arista viva. En un gráfico adimensional, en el que la sumersión relativa se expresa en función del número de Froude, se delinearon para cada caso las regiones en las que no se formaron vórtices con arrastre de aire. Se determinó el tipo de vórtice para cada punto y se delinearon las regiones donde no se forma ningún vórtice. Se comprobó que, a medida que aumenta el número de Froude, es necesaria una mayor sumersión relativa para evitar el ingreso de aire hacia la toma sumergida. Además, la toma de arista viva requirió una mayor sumersión relativa que la toma de perfil acampanado, en el rango de número de Froude ensayado, para evitar la formación de vórtices que atrapen aire. Se comprobó, en los vórtices de tipo B, que los periodos de ingreso de aire eran más prolongados cuando se instalaba una toma de arista viva para las mismas condiciones hidráulicas que para la toma de perfil acampanado

Chromosome assignment of eight SOX family genes in chicken

Chromosome locations of the eight SOX family genes, SOX1, SOX2, SOX3, SOX5, SOX9, SOX10, SOX14 and SOX21, were determined in the chicken by fluorescence in situ hybridization. The SOX1 and SOX21 genes were localized to chicken chromosome 1q3.1-->q3.2, SOX5 to chromosome 1p1.6-->p1.4, SOX10 to chromosome 1p1.6, and SOX3 to chromosome 4p1.2-->p1.1. The SOX2 and SOX14 genes were shown to be linked to chromosome 9 using two-colored FISH and chromosome painting, and the SOX9 gene was assigned to a pair of microchromosomes. These results suggest that these SOX genes form at least three clusters on chicken chromosomes. The seven SOX genes, SOX1, SOX2, SOX3, SOX5, SOX10, SOX14 and SOX21 were localized to chromosome segments with homologies to human chromosomes, indicating that the chromosome locations of SOX family genes are highly conserved between chicken and human

Combining hands-on and virtual experiments for enhancing fluid mechanics teaching: A design-based research study

Fluid Mechanics courses comprise both theoretical and laboratory modules. In developing nations, computer-assisted techniques are not commonly applied in Fluid Mechanics instruction. Forced by the COVID-19 pandemic, South American universities are, however, using them for online teaching. This contribution presents an 8-semester (2016–2019) educational intervention over an undergraduate Fluid Mechanics course. It mainly blends physical (hands-on) and virtual experiments (computer fluid dynamics-based simulations) for the laboratory module, which are complemented by flipped classroom-based prompts for the theoretical module. The intervention follows design-based research as a research method and is guided via conjecture mapping and fidelity of implementation standards. Our results suggest that the intervention improves fluid mechanics laboratory instruction, although improvements depend upon the participation of other educational actors such as teaching assistants and laboratory technicians to some extent. Laboratory report grades (the assessment instrument) follow the Gompertz probability distribution. Following UNESCO standards, a portion of the intervention output is shared as open educational resources. This contribution encourages upscaling the educational intervention through the formation of cooperative clusters to build common-pool Fluid Mechanics resources. Learning scientists have underlined the need to better understand laboratory instruction processes. They have been addressed in very few instances in developing countries. We believe that this study has the potential to provide valuable insights on the matter.Fil: Gutierrez, Ronald R.. Pontificia Universidad Católica de Perú; PerúFil: Escusa, Frank. Pontificia Universidad Católica de Perú; PerúFil: Lyon, Joseph A.. Purdue University; Estados UnidosFil: Magana, Alejandra J.. Purdue University; Estados UnidosFil: Cabrera, Jose H.. Pontificia Universidad Católica de Perú; PerúFil: Pehovaz, Richard. Pontificia Universidad Católica de Perú; PerúFil: Link, Oscar. Universidad de Concepción; ChileFil: Rivillas Ospina, German. Universidad del Norte; ColombiaFil: Acuña, Guillermo J.. Universidad Pontificia Bolivariana; ColombiaFil: Kuroiwa, Julio M.. Universidad Nacional de Ingenieria; PerúFil: Guzman, Monica X.. Universidad Católica Boliviana; BoliviaFil: Latosinski, Francisco Guillermo. Universidad Nacional del Litoral; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentin