94 research outputs found
Organizaciones sustentables: caracterización y formas de instrumentación
Fil: Verón, Carmen S. Universidad Nacional Villa María; Argentina..Fil: Marcolini, Silvina B. Universidad Nacional Villa María; Argentina..Fil: Cipollone, Daniel E. Universidad Nacional Villa María; Argentina..Fil: Lopez Pujato, María C. Universidad Nacional Villa María; Argentina.
La rentabilidad agrícola como condicionante de la decisión de producción en las empresas de la región centro de Argentina
The objective of this study is to analyze whether Argentinian farmers from the central region make production decisions considering the calculations of profitability obtained at the time of sowing, or if there are other factors that have an impact such as diversity and alternation of the crops, climate predictions, commercialization problems, expectations of the sectorial policy, technology, and others. The alternatives examined link the production of soy, corn and wheat, which are annual crops, in the provinces of Santa Fe, Córdoba and Buenos Aires, as dependent variable, and the gross margins of soy, corn and wheat in each zone. The period under study covers the years 2011 to 2016. Although profit margins constitute an important element that conditions the production decision, it is clear that other elements are considered at the time of deciding which crop to produce, with the exception of the province of Santa Fe, favored by its lands, climate and logistics, where results evidence a relationship between the crops of higher margin and farmed areas. Future studies can attempt to identify other elements that condition the production and even the degree to which each influences it.El objetivo del trabajo es analizar, si el productor agrícola argentino de la región centro, toma decisiones de producción en virtud de los cálculos de rentabilidad que realiza al momento de sembrar o hay otros factores que influyen como la diversidad y alternancia de los cultivos; pronósticos climáticos, problemas de comercialización, expectativas de la política sectorial, tecnología y otros. Las alternativas examinadas vinculan la producción de soja, maíz y trigo que son cultivos anuales, en las provincias de Santa Fe, Córdoba y Buenos Aires, como variable dependiente y los márgenes brutos de soja, maíz y trigo de cada zona. El período bajo estudio abarca los años 2011 a 2016. Si bien los márgenes de ganancias constituyen un elemento importante que condiciona la decisión de producción, resulta claro que excepto en la provincia de Santa Fe, favorecida por sus tierras, clima y logística, en la que los resultados evidencian una relación entre los cultivos de mayor margen y las áreas sembradas, otros elementos son considerados al momento de decidir el cultivo a producir. Futuras investigaciones pueden intentar identificar otros elementos que condicionan la producción e incluso la medida en que cada uno influye en ésta
On an efficient k-step iterative method for nonlinear equations
[EN] This paper is devoted to the construction and analysis of an efficient k-step iterative method for nonlinear equations. The main advantage of this method is that it does not need to evaluate any high order Frechet derivative. Moreover, all the k-step have the same matrix, in particular only one LU decomposition is required in each iteration. We study the convergence order, the efficiency and the dynamics in order to motivate the proposed family. We prove, using some recurrence relations, a semilocal convergence result in Banach spaces. Finally, a numerical application related to nonlinear conservative systems is presented. (C) 2016 Elsevier B.V. All rights reserved.This work was supported in part by the project MTM2011-28636-C02-01-{01,02} of the Spanish Ministry of Science and Innovation.Amat, S.; Bermúdez, C.; Hernández-Verón, MA.; Martínez Molada, E. (2016). On an efficient k-step iterative method for nonlinear equations. Journal of Computational and Applied Mathematics. 302:258-271. https://doi.org/10.1016/j.cam.2016.02.003S25827130
Proposals for Innovation and Improvement of the Quality of Life in Caprine Pastoralist Communities of Subsistence in the Monte Desert, Argentina
In a satisfactory alliance between the main environmental policy organizations and the academy, the National Observatory on Land Degradation and Desertification (ONDTyT) is created. The ONDTyD provides information regarding status and trends of land degradation/desertification in order to promote prevention and mitigation measures used for advising public and private decision-makers in Argentina. It is based in the development of 17 Pilot Sites that constitutes the local level network, providing bio-physical and socio-economic indicators of land degradation.
In this network the pilot site of the Monte, the largest dry region of Argentina (Lavalle desert, Mendoza), aims to improve the living conditions of native communities dedicated to subsistence goat farming, located below the poverty line. Precipitation ranges from 80-100 mm/year, strongly affecting productive activities. The proposal includes innovative traits in an area whose natural resources have been devastated. It is framed within a conception of rural territory development generating sustainable development strategies of rural indigenous communities, improve the status of the ecosystem through an integral management of natural and cultural resources, and improve socioeconomic conditions of inhabitants, compatibilizing ecosystem regeneration with investment in infrastructure and services, diversification of productive activities and generation of employment.
An interdisciplinary group designed the proposal and the integrated desertification assessment in the fields with active community participation through their knowledge, land and livestock. The pilot case can be replicated throughout the territory. The work combines participatory and integrated methodologies, showing that the Observatory is a successful example of partnership building between the political and scientific-technological sectors in Argentina
Fungal peritonitis in patients on peritoneal dialysis: Twenty five years of experience in a teaching hospital in Argentina
ABSTRACT Fungal peritonitis is a rare but serious complication of peritoneal dialysis. The aim of this study was to analyze peritonitis rates, associated factors, clinical course, microbiological aspects, therapeutic regimens, and outcome of patients with fungal peritonitis in the dialysis center of a teaching hospital over the last 25 years. A hundred and eighty three episodes of peritonitis were detected and microbiologically documented in 57 patients. Fungi were identified in eight episodes (4.37%) occurring in seven female patients. The fungal peritonitis rate was 0.06 episodes/patient-year. Gram and Giemsa stains were positive in five out of eight dialysate fluids. The causative microorganisms were: Candida albicans in five episodes, and Candida parapsilosis, Candida glabrata, and Neosartorya hiratsukae in the remaining three. Antibiotics were administered to all but one patient, within 3 months before fungal peritonitis was detected. All patients required hospitalization, and antifungal therapy was administered in all episodes. The Tenckhoff catheter was removed in seven out of eight fungal peritonitis. All patients recovered from the fungal episodes. In the group of patients studied, it is concluded that recent exposure to antibiotics and female sex, were strongly associated with the development of fungal peritonitis by yeasts. The peritonitis caused by the environmental filamentous fungus did not require antibiotic pressure. Direct microscopy of the dialysate pellet was extremely useful for the prompt management of the fungal episode. Fungal peritonitis preceded by multiple episodes of bacterial peritonitis always determined the definitive dropout of the patient from the peritoneal dialysis program. Patients with de novo yeastrelated peritonitis could continue on the program. Key words: peritoneal dialysis, fungal peritonitis, peritonitis rates, causative microorganisms, Candida albicans, Candida spp. RESUMEN Peritonitis fúngica en pacientes en diálisis peritoneal: la experiencia de 25 años en un hospital universitario de la Argentina. La peritonitis fúngica es una complicación infrecuente pero grave de la diálisis peritoneal. Los objetivos de este trabajo fueron el análisis de las tasas de peritonitis, factores asociados, aspectos clínicos y microbiológicos, esquemas terapéuticos y evolución de los pacientes afectados. Se detectaron y documentaron microbiológicamente 183 episodios de peritonitis en 57 pacientes. Se identificaron hongos en ocho episodios (4,37%) en siete pacientes, todos ellos de sexo femenino. La tasa de peritonitis fúngica fue 0,06 episodios/paciente-año. Las coloraciones de Gram y Giemsa revelaron la presencia de microorganismos en cinco de los ocho líquidos de diálisis evaluados. Los microorganismos causales fueron Candida albicans en cinco episodios y Candida parapsilosis, Candida glabrata y Neosartorya hiratsukae en los otros tres. Todos estos pacientes, excepto uno, habían recibido antibióticos en los tres meses previos al episodio de peritonitis fúngica. El catéter de Tenckhoff fue extraído en siete de los ocho episodios. Todos los pacientes evolucionaron favorablemente. Concluimos que en la población estudiada el sexo femenino y la administración reciente de antibióticos estuvieron estrechamente relacionados con el desarrollo de peritonitis fúngicas por levaduras. Sin embargo, la peritonitis causada por el hongo filamentoso ambiental no requirió de la presión antibiótica. La microscopía del sedimento del líquido de diálisis fue útil en el manejo precoz del episodio. La peritonitis fúngica precedida por múltiples episodios de peritonitis bacteriana determinó siempre la exclusión definitiva del paciente del programa de diálisis peritoneal. Los pacientes con peritonitis de novo por levaduras, en cambio, pudieron continuar en él
Abuelos 2.0: ampliando sus vínculos sociales
Las redes sociales adquieren día a día mayor importancia en la vida de las personas y son el espacio de interacción social más utilizado. A través de estas redes, se forman comunidades virtuales donde sus usuarios interactúan con personas de todo el mundo con quienes encuentran aficiones o intereses en común. Funcionan como una plataforma de comunicaciones que permite conectar gente que se conoce o que desea conocerse, y que les permite compartir fotos y vídeos, entre otros recursos. Si bien algunos adultos mayores tienen nociones básicas de computación, la gran mayoría no comprenden el funcionamiento de las redes sociales. Esto hace que este gran grupo social sea el de menor participación en dichas redes, quedando excluidos de estas comunidades virtuales, que en muchas oportunidades se transforma en la única compañía, ya que muchos adultos viven en soledad. En el presente artículo se presenta el Proyecto de Voluntariado Universitario “Abuelos 2.0: Me Gusta”, mediante el cual se pretende integrar a los adultos mayores a Facebook (la red social más popular) para proveerles una herramienta de comunicación que les permita intercambiar ideas, reencontrarse con otras personas, compartir fotos y videos, etc., e incluso menguar su soledad en caso de adultos mayores que viven solos. El propósito es permitir a los adultos mayores ampliar sus vínculos sociales y generar un espacio de dispersión y entretenimiento, mejorando su calidad de vida, manteniéndolos activos mental y emocionalmente.Sociedad Argentina de Informática e Investigación Operativa (SADIO
Elementos conceptuales y metodológicos para la evaluación de impactos ambientales acumulativos (eiaac) en bosques subtropicales : el caso del este de salta, argentina
163-178Northern Argentina experienced an unprecedented deforestation rate of xerophitic forests as a consequence of agricultural expansion. In the Province of Salta, 26 percent of the forest were removed between 1977 and 2008. At the end of 2007, just before the No. 26331 Law of Native Forest Protection was voted by the Congress, the highest annual rate of deforestation was registered, reaching a value of 2.1 percent. Regarding this situation, indigenous people of Eastern Salta along with the "criollos" (local small ranchers) appealed to the National Supreme Court of Justice for legal protection. The Court requested the province to elaborate a Cumulative Environmental Effects Assessment (CEEA) regarding the process of logging and deforestation in four departments of Salta Province (San Martín, Rivadavia, Santa Victoria, and Orán). The aim of this work is to present a conceptual framework to conduct a CEEA in eastern Salta and to present the evidences and existing methodologies to characterize the impacts of deforestation. The conceptual framework suggested depends on the quantitative characterization of the changes in the provision level of key ecosystem services as a function of the stress and/or disturbance level (in this case deforestation). Based on the literature and our own data, the effects of deforestation on four key ecosystem services have been assessed: C dynamics, energy balance and greenhouse gases emissions, water dynamics and landscape structure. Deforestation produced emissions of 2000 t of CH 4, 200 t of N 2O, above 20 Gg of C/year, a 1.1 watt/m2 reduction in reflected radiation and 4400 TJ radiative energy emissions caused by deforestation fires, increases in the risk of soil salinization and landscape fragmentation. Considering these aspects of the structure and functioning of the ecosystems provides objective elements to evaluate management alternatives and to elaborate monitoring programmes. To consider such management and monitoring alternatives arises technical challenges but also institutional and political ones
A family of iterative methods that uses divided differences of first and second orders
The family of fourth-order Steffensen-type methods proposed by Zheng et al. (Appl. Math. Comput. 217, 9592-9597 (2011)) is extended to solve systems of nonlinear equations. This extension uses multidimensional divided differences of first and second orders. For a certain computational efficiency index, two optimal methods are identified in the family. Semilocal convergence is shown for one of these optimal methods under mild conditions. Moreover, a numerical example is given to illustrate the theoretical results.Peer ReviewedPostprint (author's final draft
PELLETS DE KAOLIN POROSOS UTILIZADOS COMO SISTEMA DE LIBERACIÓN LENTA DE FEROMONA BENZALDEHYDE PARA CAPTURAR TRIATOMINOS
El objetivo de este trabajo es estudiar las propiedades de los gránulos de caolín porosos que se aplicarán como un sistema de liberación lenta de feromonas, para la captura de vectores de la enfermedad de Chagas.CONACYT – Consejo Nacional de Ciencia y TecnologíaPROCIENCI
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