Le Corbusier en La Plata. La casa para el doctor Curutchet y el mito funcionalista

Producción CientíficaLa vivienda-consultorio de Le Corbusier para el Dr. Curutchet en la ciudad de La Plata, se proyectó siguiendo las peticiones del propietario, cuyo interés era la construcción de una casa según los principios funcionalistas. Le Corbusier aprovechó este encargo para diseñar un edificio en donde se armonizó la aplicación de sus cinco puntos con la incorporación de los nuevos elementos de su vocabulario formal: el doble plano (muro−pared) —cerrado como una caja de cerillas— se eleva del suelo mediante «pilotis», aislándose con el «pan de verre», protegido del sol gracias al «brise-soleil». Situado frente a un parque, el tema central fue su incorporación visual a un doble jardín: bajo la vivienda y suspendido, ambos enlazados gracias a un árbol de nueva plantación. El resultado concluyó en un brillante ejercicio formal, y un resultado plástico más allá de los intereses funcionalistas de Curutchet. Paradójicamente, el edificio es un paradigma de la arquitectura moderna, en su forma, construcción e incorporación a la trama urbana de ciudad de La Plata. The Le Corbusier´s housing-consulting to Dr. Curutchet in La Plata town, was designed following the owner requests. Le Corbusier´s interest was to build a house with functional principles. Even though LC did not know neither the place nor the owner, he designed a building bringing into harmony his five points and the new elements from his formal vocabulary: the double plane (wall–wall) – closed like a matchbox – goes up from the floor through «pilotis», using the «pan de verre» for isolation and protected from the sun with the «brise-soleil». Placed in front of a park, the project main point was to incorporate a double garden: one bellow the house and the other in suspension. Both gardens were connected by a just planted tree. The result of joining architectural elements with vegetables ones ended with a brilliant formal exercise and with a plastic result beyond Curutchet functionalist interests. Paradoxically, the building is a modern architecture paradigm, in its shape, construction and its incorporation to the urban area of the city of La Plata.Teoría de la Arquitectura y Proyectos Arquitectónico

Annual cool-season forage systems for fall grazing by cattle

Includes bibliographical references.2015 Fall.Extending the grazing season is one method that beef producers can use to reduce the need for preserved forages and supplements as these are the major inputs influencing profitability of their operations. Annual forages planted during mid- to late-summer have great potential for extending the grazing season into the fall and early winter in northern Colorado and similar environments. The development of forage systems for livestock operations must start with selection of forage species/cultivars that can yield enough biomass and have a high enough nutritive value to meet the requirements of the livestock to be fed. Accordingly, the research in this dissertation started with an evaluation of nine forage brassica cultivars from which four were chosen based on their unique traits. Barnapoli rape (Brassica napus L. var. napus) had the highest yields and stood up under a snow load; Groundhog radish (Raphanus sativus var.oleifer Strokes) and Barkant turnip (Brassicas rapa L. var. rapa) had fast growth and their bulbs provided extra feed and penetrated the soil, potentially reducing compaction; and Pasja hybrid (Chinese cabbage [Brassica rapa L. chinensis] x Turnip hybrid) had a high leaf-to-stem ratio which provided high quality forage for beef cattle. These were combined in a four-way mixture and evaluated in subsequent studies. In addition, the above study evaluated the impact of planting date on resulting yields of the brassicas and determined that they need to be planted by mid- to late-July to yield high amounts of biomass that can be stockpiled for fall grazing. The nutritive value of the brassicas was high and did not decline over time, but they were very low in fiber which can create rumen upset for beef cattle grazing them in monocultures or in brassica only mixtures. To develop a more balanced diet for beef cattle, the brassica mixture was seeded with cool-season grasses (triticale [×Triticosecale Wittm ex A. Camus {Secale x Triticum}], winter wheat [Triticum aestivum L.], and barley [Hordeum vulgare L.]) following a warm-season hay crop (pearl millet [Pennisetum glaucum L.]) that was either controlled or allowed to regrow. When the latter was controlled by spraying, brassicas dominated the mixtures to the detriment of the cool-season grasses which contributed little to available dry matter. The seed proportions of the cool-season grasses within the mixture were much lower than those used when grown in monocultures. When the proportions of cool-season grasses within mixtures were increased, their contribution to yield increased. Oats (Avena sativa) were particularly competitive when grown with the brassica mix. When the millet was allowed to regrow, it dominated the available dry matter, which influenced overall yield and nutritive value of the mixtures. Mixtures of cool-season forages and millet regrowth had lower quality than the same mixtures grown where the millet was controlled. This resulted from the brassicas dominating the mixtures where the millet regrowth was controlled, which resulted in higher quality that will likely require fiber supplements for grazing cattle. Mixtures grown with millet had higher fiber content, which negates the need for fiber supplementation. Cool-season forages and mixtures were also interseeded into corn at the V6 growth stage, which resulted in higher quality biomass on offer to beef cattle grazing cornstalks during fall and winter months. Their higher quality negates the need for supplementation, especially of protein, that is usually required to offset the low nutritive value of cornstalks. Of the forages evaluated, the brassica mix and annual ryegrass (Lolium perenne L. ssp. multiflorum [Lam.] Husnot) had the highest yields which was the determining factor for interseeded cool-season forages to compete with the costs of preserved forages that are normally used as supplements for beef cattle grazing cornstalks. Thus, the forage systems described in this dissertation provide insight into how annual forages can extend the grazing season into the fall and early-winter months, reducing the need for preserved forages to be fed in beef cattle operations. Sustainability of production systems can be enhanced when producers integrate current knowledge into their operations. Planting annual forages has the potential to benefit production of livestock and crops

Implementation of Irrigation with Dairy Cattle Manure for Tropical Perennial Pastures in Costa Rica

Animal manures allow nutrients recycling in cropping systems, while contributing to the fulfillment of environmental standards. Pasture irrigation with animal manures has been fostered for Costa Rican dairy farms over the last 15 yr. A lack of information and training regarding irrigation and management of animal manures has led to the implementation of diverse methods by producers, but those have not yet been characterized. This study aimed to describe the current management of Costa Rican dairy farms irrigating perennial pastures with slurries. The farms were mostly grass-based systems with supplements fed to cows during the time spent at the milking parlor and/or in feeding stalls through the day. Farms collect manure when facilities are washed with water, which is then stored in plastic tanks or cement structures for less than 1 day before irrigating pastures. The amount of water used by dairy producers was greater than the recommended water/manure ratio (13.4 vs. 4.0 L kg–1), with only one farm reporting values below this ratio. Slurries were sampled and analyzed for their nutrient and microbial content. Both nutrient and microbial content varied in this study due to factors specific to each farm, especially with respect to water management. The variability found in water use among farms and regions (2.4–36.7 L kg–1) may generate unintended consequences from an environmental standpoint. Sustainability of Costa Rican dairy farms can be enhanced if specific guidelines for manure irrigation are developed, which could have benefits for chemical fertilizer use and environmental effect.Universidad de Costa Rica/[739-B7-063]/UCR/Costa RicaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Agroalimentarias::Centro de Investigación en Nutrición Animal (CINA)UCR::Vicerrectoría de Docencia::Ciencias Agroalimentarias::Facultad de Ciencias Agroalimentarias::Escuela de Zootecni

Producción de biomasa y valor nutricional del pasto Phalaris arundinacea, ("pasto alpiste" o Reed canarygrass) con tres edades de corte

Evaluar el efecto de tres edades de corte sobre la producción de biomasa y el valor nutricional del pasto phalaris arundinacea en parcelas experimentales bajo condiciones de una finca con un sistema de corte y acarreoUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Agroalimentarias::Centro de Investigación en Nutrición Animal (CINA

Tutored notes: a support to teaching

Para facilitar el aprendizaje a los alumnos establecemos un sistema llamado Apuntes Tutelados que guían al alumno tanto en la clase teórica como en el estudio de la asignatura.To facilitate learning students establish a system called Tutored Notes to guide the student in both the classroom and in the theoretical study of the subject.Peer Reviewe

Fenología, producción y valor nutritivo del pasto alpiste (phalaris arundinacea) en la zona alta lechera de Costa Rica

Phenology, yield and nutritional value of reed canary grass (Phalaris arundinacea) in dairy farms in the highlands of Costa Rica. Dry matter yield, nutritional value and phenology of reed canary grass (Phalaris arundinacea) were evaluated with three harvest ages (49, 70 and 91 days), during a year and a half, in a commercial dairy farm in the district of Santa Rosa de Oreamuno, Cartago Province. Average dry-matter yield was 3101 kg.ha-1.regrowth-1 period. Average nutritional value was 17.77% CP, 55.89% NDF, 35.93% ADF, 4.14% lignin and 66.87% IVDMD on dry-matter basis. Estimated energy content expressed as TDN, DE, ME, NEL (3X) and NEG was 63.07%, 2.76, 2.13, 1.31 and 0.81 Mcal.kg-1 of DM, respectively. CP fractioning of African star grass (Cynodon nlemfuensis) and perennial ryegrass (Lolium perenne), were compared with that of reed canary grass; the main contribution was obtained from the insoluble degradable fraction (B2+B3) in the temperate species, while african star grass had a higher contribution from the degradable fraction (A+B1). Average phenological stage of reed canary grass was 5.96 green leaves per regrowth and its leaf stage must be 5 to 6 leaves to optimize dry matter yield and nutritional value. Reed canary grass has been used in several dairy farms and has gained importance as an option that can withstand the weather conditions in the highlands of Costa Rica; olso, there are already companies importing sexual seed of this species.Se evaluó la producción de biomasa, el valor nutricional y la fenología del pasto alpiste (Phalaris arundinacea) con 3 edades de cosecha (49, 70 y 91 días), a lo largo de año y medio, en una finca comercial de ganado lechero ubicada en Santa Rosa de Oreamuno, provincia de Cartago. La producción de biomasa promedio para el pasto alpiste fue 3101 kg.ha-1.corte-1 de MS. La composición nutricional promedio fue de 17,77% PC, 55,89% FDN, 35,93% FDA, 4,14% lignina y 66,87% DIVMS y su contenido energético expresado como TND, ED, EM, ENL (3X) y ENG fue 63,07%, 2,76; 2,13; 1,31 y 0,81 Mcal. kg-1 de MS, respectivamente. Se comparó el fraccionamiento de la PC de los pastos estrella africana (Cynodon nlemfuensis) y ryegrass perenne (Lolium perenne) con la del pasto alpiste, con el que las especies de clima templado presentan un aporte principalmente de la fracción insoluble degradable (B2+B3), mientras el estrella africana lo hace a nivel de la fracción degradable (A+B1). La edad fenológica promedio del pasto alpiste fue 5,96 hojas verdes por rebrote y su edad debe encontrarse entre 5 y 6 hojas para optimizar su producción de biomasa y valor nutricional. El pasto alpiste se ha utilizado en diversas fincas de ganado de leche y ha adquirido importancia como una opción que puede soportar las condiciones climatológicas de las regiones altas de Costa Rica; asimismo, ya hay empresas que importan semilla sexual de dicha especie

Fichas de forrajes (piso, corte, arbustivas)

Documento realizado en el marco del Proyecto de la Red Nacional de Pastos y Forrajes, Coordinado por Cámara Nacional de Productores de Leche. Poryecto: Validación y transferencia de casos de éxito, técnicas y variedades forrajeras adaptadas al cambio climático, para su uso en ganado bovino de Costa RicaFundecooperación para el Desarrollo Sostenible/[]//Costa RicaDirección de Cambio Climático/[]/DCC/Costa RicaUCR::Vicerrectoría de Docencia::Ciencias Agroalimentarias::Facultad de Ciencias Agroalimentarias::Escuela de ZootecniaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Agroalimentarias::Centro de Investigación en Nutrición Animal (CINA

Evaluación agronómica y nutricional del pasto estrella africana (Cynodon nlemfuensis) en la zona de Monteverde, Puntarenas, Costa Rica. II. Valor nutricional

The nutritional value of african star grass (Cynodon nlemfuensis)-based pastures was analyzed in 4 commercial dairy farms in the Monteverde region (latitude 10°20’, longitude 84°50’, 800 to 1200 masl), every other month during a 2-year period. Sampling was carried out in the paddock ready to be grazed and samples were hand-plucked leaving a 10 cm stubble height, simulating the consumption made by lactating cows. Average nutritional value for the 2 years was 23.57% DM, 20.27% CP, 2.67% EE, 10.97% ashes, 64.21% NDF, 34.95% ADF, 4.06% lignin and 68.02% IVDMD on a dry matter basis. Estimated energy content for the variables of TDN, DE, ME, NE L (3X), and NE G was 61.37%, 2.71, 2.05, 1.25 and 0.78 Mcal.kg -1 DM, respectively. Nutritional value of african star grass varied along the year, as it is sensitive to weather conditions. The farms with influence from the Pacific slope are less affected in forage quality than those with Atlantic influence. CP content was higher in this study than in previous evaluations for this species elsewhere and, in general, for tropical grasses as well. Protein is not a limiting factor for dairy cattle grazing african star grass, and its supply must use sources that allow an efficient utilization of soluble N by rumen microorganisms. The 25-day rotation systems in Monteverde must be flexible to allow, jointly with fertilization programs, the optimization of the productivity and persistence of the pastures.Se analizó el valor nutricional del pasto estrella africana (Cynodon nlemfuensis) a lo largo de 2 años en muestreos bimensuales, en 4 fincas comerciales de ganado lechero ubicadas en los cantones de Tilarán y Central (latitud 10°20’ N, longitud 84°50’, altitud 800 a 1200 msnm) de las provincias de Guanacaste y Puntarenas, respectivamente. Las muestras se recolectaron en el aparto siguiente a ser pastoreado y se utilizó una altura de cosecha de 10 cm, para simular el pastoreo que hacen los animales. La composición nutricional promedio para los 2 años de evaluación fue de 23,57% MS, 20,27% PC, 2,67% EE, 10,97% cenizas, 64,21% FDN, 34,95% FDA, 4,06% lignina y 68,02% DIVMS y su contenido energético para las variables de TND, ED, EM, EN L (3X) y EN G fue 61,37%; 2,71; 2,05; 1,25 y 0,78 Mcal.kg -1 de MS, respectivamente. El valor nutricional del pasto estrella africana varió a lo largo del año como resultado de la climatología de la zona de Monteverde, siendo las fincas con influencia de la vertiente del Pacífico las de menor afectación en la calidad del forraje. El pasto estrella africana mostró un contenido de PC superior a lo reportado para dicha especie y, en general, para pastos tropicales, por lo cual no es limitante para la producción láctea, y la suplementación del ganado lechero en la zona debe utilizar fuentes que permitan una utilización eficiente del N soluble a nivel ruminal. La rotación del pasto estrella cada 25 días debe ser flexible para permitir, en conjunto con programas de fertilización, optimizar la productividad de las pasturas y su persistencia

Análisis financiero para la implementación de un sistema estabulado en una finca de ganado de leche en Costa Rica

Financial analysis for the implementation of a feedlot in a dairy cattlefarm in Costa Rica. The financial feasibilityfor the implementation of a feedlot in a dairyfarm was evaluated. The evaluation was madein the functional departments (production,marketing, human resources and finances) todetermine the technical situation before changingthe productive system. The reproductive andproductive records were used to map out thegrowing of the herd with the program Invest-GA®. Financial analysis was carried out bysearching for market information, estimating theborrowing capacity of the company and nominalcash flows made from financial records of theDairyProfit® program. The net present value(NPV) was obtained as a financial indicatorfrom the different projections. A sensitivityanalysis was made varying the production levelof the animals (one-dimensional), and a marginalanalysis was made by using the incremental NPVobtained in the projections versus the productivesystem without investments. The best projectionfor the dairy farm was the investment in a stable,a mixer and receiving a lower payment for theadditional milk delivered to the factory obtaining¢237.129.530,15 and ¢89.169.075,85 for the NPV and incremental NPV, respectively. The receivingof the product by the dairy factories is one ofthe main factors affecting the implementation ofmore intensive systems in the dairy farms of CostaRica. Productivity of dairy farms determines theircompetitiveness, because as the specialization indairy production systems grows, there are moreexternal factors that may affect performanceand, therefore, internal control systems must beaccurate to adapt to the current situation.Se evaluó la viabilidad financiera para la implementación de un sistema de producción de ganado de leche estabulado, en una finca que utiliza un sistema semiestabulado. La evaluación se realizó por medio del análisis de las áreas funcionales de la empresa (producción, mercadeo, recursos humanos y finanzas), con el fin de determinar la situación técnica previa a un cambio en el sistema productivo, y del uso de registros productivos y reproductivos en el programa Invest-GA® para el flujo de hato. El análisisfinanciero consistió en la búsqueda de información de mercado, estimación de la capacidad de endeudamiento de la empresa y elaboración de flujos de caja nominales a partir de registros financieros del programa DairyProfit®. Con los diferentes escenarios proyectados se obtuvo el valor actual neto (VAN) como indicador financiero. Se realizó un análisis de sensibilidad unidimensional con variaciones en el nivel productivo individual de los animales y un análisis marginal por medio del VAN incremental mostrado por los diferentes escenarios, comparado con el desarrollo de la finca sin realizar inversiones. El escenario que mostró ser más viable fue la inversión en la construcción de instalaciones para estabulación, compra de un carro mezclado

El Color de Luís Barragán

Producción CientíficaLa publicación indaga sobre la luz y los muros, los dos elementos compositivos empleados por el arquitecto Luís Barragán en la génesis proyectual de sus espacios. Son con los que, sólo inicialmente, parece que el arquitecto crea sus espacios. Uno, el muro, inseparable del otro, la luz y su descomposición en colores, unidos ambos en el ambicioso proceso de generar la percepción arquitectónica.Teoría de la Arquitectura y Proyectos Arquitectónico