Design and evaluation of a no-tillage seeder for small scale vegetable production using a two-wheeled tractor in Coahuila, Mexico

Currently used conventional tillage systems for small-scale vegetable production in the region of Saltillo, Coahuila, Mexico require a considerable amount of hand labor, energy and materials for all activities. Seedbed preparation can require up to 60% of the total production cost in some systems in Mexico. Further, soil is degraded and eroded due to the system. Conservation tillage may reduce costs and prevent soil degradation, but appropriate tools, such as, no-tillage seeders for small-scale farmers are not available. This papers reports on the design and construction of a prototype of a no-tillage seeder for small-scale conservation tillage using a 2-wheeled tractor. Three main functions received particular attention: opening of the soil, placing seed and/or fertilizer and closing the slot. Because of its vapor conservation and good seedling emergence, tools to create T-shaped slots were chosen, with adapted depth control and closing and covering devices. A systematic design process was applied in order to reach the required decisions. Function diagrams were defined from where morphologic charts guided the selection of the configuration of the seeder. A preliminary evaluation included testing of two furrow opener disc types (notched and fluted), and four crop residue levels, 0, 30, 60 and 100%, with respect to performance of the seeder. An evaluation showed that with low cover amounts a consistent and firm seed cover was obtained, but emergence quality decreased due to insufficient residue cover. The notched disc had a better performance than the fluted disc. The inverted T-shape in the soil was not always sustained due to technical flaws. It was possible to build a prototype under 2000 dollars with basic tools in a local workshop. Further research will focus on the biological performance and improvement of the mechanical components and performance

Soil workability as a basis for advice on tillage activities

In the tropical area of Mexico, when and how to carry out tillage is a qualitative decision. There is no quantified information about the interaction between a chosen process of cultivation, soil type and weather, which dictate the tool and power requirements. Waste of energy and soil degradation by erosion and compaction, and lack of timeliness are recognized problems caused by inadequate tillage management in the tropical area of Mexico.In this thesis, the workable range of soils was quantified in the field, and the limits of that range, represented in the laboratory by tests to soil samples. This information is the basic part of a soil workability based procedure which is developed as a decision support tool for selecting specific tillage practices. The methodology was conceived for application in the tropical area of Mexico. For this reason a description of the area under study in relation to the present agricultural production system, including tillage related problems, was presented in Chapter 2 .In Chapter 3, The field and the laboratory studies to quantify the workable range of soils in the area, were treated. The methodology and results from those studies were presented and discussed, considering the technological result of the tillage operation and the input of energy at a range of soil moisture contents. Empirical relationships between initial moisture content and the technological result of tillage showed that results from Loam and Clay soils changed from optimum to sub-optimum at soil water potentials that rather coincide with the plastic limit in relatively moist soil. As soil was drying out , the implement result changed from optimum to sub-optimum at soil water potentials well below to that for the shrinkage limit, so the actual field work was smaller than the theoretical friable range of the soils. The minimum input of specific energy to obtain optimum results was close to the soil water potential, where results changed to sub-optimum as the soils where drying out. Observations in a Sandy soil indicate that required technological result is attained at almost any moisture content.The thresholds that delimit the optimum and sub-optimum results in the field are represented by means of laboratory tests, air permeability test (for a wet limit) and a Drop test (for the dry limit). The methodology and results from laboratory experiments are also presented, and any links and discrepancies in representing field results were discussed. The thresholds established by the results of the laboratory tests agree well with the findings in the field. This allow that worability limits in terms of soil water potential can be established for other soils in the area by means the mentioned laboratory tests.This was the main part of this research since it was the development of the methodology to characterize the workable range of soils for the area under study.Once the workable range of a soil is known, whether this status is present on time (during the workable period within the cropping calendar) depends on the interactions between soil characteristics and weather. In Chapter 4, the necessary data used to model the soil-water balance in order to obtain the relevant information for tillage planning and operation, was discussed. The possibility of use PTF's for deriving the hydraulic characteristics of soils from limited textural data normally available in the area under study was explored, as they are required by deterministic soil-water models. It was found that PTF's developed in The Netherlands estimate well the hydraulic characteristics for a Loam soil of the area under study.The soil workability and the soil-water balance are the 'tools' to calculate the workable periods, but in this area the data available to determine both 'tools' is available at different spatial scales. The possibility of extending the methodology applied at the experimental field level to other scales and the use of workability information for operational decisions and planning was discussed in Chapter 5.To decide objectively which tillage practice will be chosen and when tillage should be carried out, a great deal of information has to be analyzed. To take advantage of the soil workability methodology developed, it shall be used within an automated procedure wherein the user need only supply its specific circumstances and receive as output the relevant information to utilize as support for planning decisions. In chapter 6 an initial version of such an automated procedure was presented.In Chapter 7 From results and discussions and having as reference the posed hypothesis, general conclusions were stated regarding the development and use of the methodology on soil workability to support the planning and operation of tillage systems in the area under study.</p

Fijación del precio del seguro obligatorio de accidentes de tránsito (SOAT) en Ecuador, período 2008 – 2012.

En el Ecuador en el 2008 se implementó el seguro de accidentes de tránsito con la finalidad de garantizar la cobertura a las víctimas de estos accidentes; luego de su primer año de funcionamiento por variaciones en los márgenes de utilidad percibidos por las aseguradoras, la tarifa disminuyó para los siguientes años. Además se expidió un nuevo reglamento para la aplicación de la Ley de tránsito en la cual se incrementaron las coberturas. Bajo ese contexto no se ha planteado un estudio que contemple la siniestralidad como criterio fundamental en el cálculo de las tarifas, manteniéndose la metodología de cálculo inicial y sin una diferenciación en las tarifas desde la reducción de éstas en el año 2009

Advertising of ultra-processed foods and beverages: children as a vulnerable population

La rápida transición nutricional en América Latina tiene como resultado el aumento pronunciado de sobrepeso y obesidad en los niños. Evidencia reciente muestra que la publicidad de comidas y bebidas ejerce gran influencia en las preferencias alimenticias de los niños. Esta población se torna centro de atención para la industria de alimentos ultra procesados y bebidas, productos comercializados agresivamente. En los países de América Latina, sólo existen reglamentos ineficientes para la publicidad de bebidas y alimentos ultra procesados, y el discurso de auto regulación prevalece sobre los reglamentos legales. Este comentario explora el importante papel de la publicidad en el desarrollo de patrones de dietas no saludables y en la obesidad de niños en América Latina, así como la necesidad de acción gubernamental y participación social en la resolución de este problema de salud pública.A rápida transição nutricional na América Latina tem como resultado o aumento pronunciado de sobrepeso e obesidade nas crianças. Evidência recente mostra que a publicidade de comidas e bebidas tem grande influência nas preferências alimentares das crianças. Essa população torna-se alvo da indústria de alimentos ultraprocessados e bebidas, produtos comercializados agressivamente. Nos países da América Latina, só existem regulamentos ineficientes para a publicidade de bebidas e alimentos ultraprocessados, e o discurso de auto-regulação prevalece sobre os regulamentos legais. Este comentário explora o papel importante da publicidade no desenvolvimento de padrões de dietas não saudáveis e na obesidade das crianças na América Latina, bem como a necessidade de ação governamental e participação social na resolução desse problema de saúde pública.The rapid nutrition transition occurring in Latin America has resulted in a sharp increase of childhood overweight and obesity. Recent evidence has shown that food and beverage advertising has a great influence on children’s eating behavior. This population has become a key target market for the ultra-processed foods and beverages industry, which is marketing products in an aggressive way. Evidence shows that Latin American countries have poor regulation of ultra-processed foods and beverages advertising, where the discourse of self-regulation still prevails over statutory regulations. The following commentary explores how advertising might play an important role in developing unhealthy dietary patterns and obesity in Latin American children, as well as the urgent need for government action and the involvement of civil society to tackle this public health issue

Adaptation and Validation of the Subtle and Blatant Prejudice Scale in a Colombian Sample

El objetivo del estudio fue establecer las propiedades psicométricas para Colombia de la Escala de Prejuicios Sutiles y Manifiestos elaborada por Pettigrew y Meertens (1995) y adaptada al español por Rueda y Navas (1996), tomando como población objetivo los inmigrantes venezolanos que han llegado a Colombia. La muestra fue de 1078 colombianos residentes en Barranquilla (Atlántico) seleccionados intencionalmente, con edades entre 18 y 78 años (M = 34.6 y DE = 13.4). Un 49% (n=523) eran hombres. Los resultados indican una consistencia interna para la escala global de α =.84 y ω = .85. La subescala de Prejuicio Sutil muestra una consistencia interna de α = .74 y ω = .75, y la de Prejuicio Manifiesto de α = .78 y ω = .80. Con el Análisis Factorial Confirmatorio se ratifica la estructura factorial, pero se cambia el ítem 17 de factor y se elimina el ítem 7, quedando en total con 19 ítems. Se describen las limitaciones.The main objective of this study was to establish the psychometric properties for Colombia of the Subtle and Blatant Prejudice Scale of Pettigrew and Meertens (1995) which was adapted to Spanish by Rueda and Navas (1996). Venezuelan immigrants in Colombia are the target population. The sample comprised 1078 Barranquilla residents (Atlantic) who were selected intentionally, with an age range between 18 and 78 years old (M = 34.6 and SD= 13.4), of whom 49 % (n=523) were male. Outcomes show a Cronbach’s alpha (α) of .84 and an Omega (ω) of .85 for the global scale. The Subtle Prejudice subscale displays α = .74 and ω = .75, while the Blatant Prejudice subscale demonstrates α = .78 and ω = .80. Confirmatory Factor Analysis confirms the underlying factorial structure, but item 17 changes factor and item 7 is eliminated, leaving a total of 19 items. Limitations are discussed

Prototipo funcional para el control y gestión de los semilleros de investigación en el programa de ingeniería de sistemas de la Universidad Libre

Los semilleros de investigación, constituyen para la facultad de ingeniería y para el programa de Ingeniería de Sistemas, la estrategia de consolidación para la Investigación formativa, permitiendo la proyección ante el contexto Local y Nacional de los desarrollos y adelantos de los diferentes trabajos y actividades en sus líneas de investigación. La necesidad de contar con un sistema de información para la gestión y seguimiento de las actividades del semillero ha motivado a la construcción de una solución integral cuya calidad garantice la usabilidad y efectividad operacional de la información requerida. Los semilleros, recolectan sus momentos de creación, de desarrollo, producción y de titulación, y en torno a ello es necesario poseer el núcleo de acción que constituye la traza de control, saber por ejemplo en qué fecha se crea el semillero, cuáles son sus integrantes, que resultados se han obtenido en los diferentes eventos y cuál ha sido su nivel de producción dentro de su historial. El programa, en la actualidad, realiza esfuerzos por integrar la información pertinente, pero solo esta actividad se refleja al interior de cada uno de los semilleros, siendo imposible poder definir métricas de control sobre el historial y seguimiento de cada uno de los semilleros, amén de no poder de referenciar para fines de presentación la producción realizada a nivel digital como muestra de la realizaciones y trabajos en los que participa el semiller

Uso del caucho reciclado para mejorar la durabilidad de la carpeta asfáltica en la Av. Dorado, JLO, Chiclayo

La presente investigación denominada “Uso de caucho reciclado para mejorar la durabilidad de la carpeta asfáltica en la Av. Dorado, José Leonardo Ortiz, Chiclayo”, en la que se planteó como problema general ¿Con el uso del caucho reciclado, se podrá mejorar la durabilidad del pavimento flexible de la Av. Dorado, José Leonardo Ortiz? Ante esta problemática, se tiene como objetivo general usar el caucho reciclado para mejorar la durabilidad del pavimento flexible de la Av. Dorado, ¿José Leonardo Ortiz? Ante esta problemática, se tiene como objetivo general usar el caucho reciclado para mejorar la durabilidad del pavimento flexible de la Av. Dorado, JLO, Chiclayo. De esta manera, se planteó como hipótesis “Si usamos el caucho reciclado es posible mejorar la carpeta asfáltica de la Av. Dorado”. El diseño de investigación es experimental, del tipo cuasiexperimental con grupo de control y de experimentación, es decir con sustitución de 0.5%, 0.75%, 1.0%, 1.5% de caucho reciclado para mejorar la durabilidad de la carpeta asfáltica. Los resultados de los efectos en la carpeta asfáltica convencional con caucho reciclado muestran mejoras en su desempeño. Los resultados obtenidos en el diseño de la mezcla asfáltica convencional indican que el caucho reciclado en las proporciones 0.5%, se encuentra dentro de los parámetros exigidos de estabilidad, porcentaje de vacíos y flujo

Caracterización de los componentes ambientales del predio Álamos (Jamundí – Valle del Cauca) como herramienta de gestión del proceso de Registro de Reserva Natural de la Sociedad Civil (RNSC).

Caracterización de determinantes ambientales del predio Álamos del municipio de Jamundí, que conlleva al registro de Reserva Natural de la Sociedad Civil ante la Unidad de Parques Nacionales Naturales - PNNCharacterization of environmental determinants of the Alamos property in the municipality of Jamundí, which leads to the registration of the Civil Society's Natural Reserve before the National Natural Parks Unit - PN

Definición y estandarización de los procesos de impacto al cliente y propuesta de implementación de un CRM para la empresa Almacén Espinoza ubicada en la ciudad de Quito para el año 2012

El presente trabajo se desarrolla para “Almacenes Espinoza”, una empresa con una trayectoria de 27 años en el mercado, dedicada a la comercialización de productos para el hogar. La empresa, a pesar de contar con una extensa cartera de clientes, no ha definido su cultura organizacional ni sus procesos con enfoque en el cliente; motivo por el cual el presente trabajo definirá a lo largo del desarrollo de siete capítulos la propuesta de implementación de un modelo CRM para la gestión de clientes