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Efecto de radiación UV–C y atmósferas modificadas activas sobre la calidad microbiológica y funcional de rúcula
(Universidad de Chile, 2012)
El objetivo de este trabajo fue evaluar el efecto de gases no convencionales como el argón (Ar), helio (He), óxido nitroso (N2O), altas concentraciones de O2 y aire, sobre el crecimiento microbiológico en hojas de rúcula (Eruca vesicaria) MPF...
The aim of this study was to evaluate the effect of novel gases such as argon (Ar), helium (He), nitrous oxide (N2O), O2 and air, on Escherichia coli inoculated on arugula leaves (Eruca vesicaria). The samples were disinfected with sodium hypochlorite (95 mg·L-1, pH 6.5) and rinsed with sterile water; the leaves were inoculated with E. coli (6,5 log CFU·g-1) and packed in different atmospheres enriched with Ar (53% Ar + 41% O2 + 6% N2); He (53% He + 42% O2 + 5% N2); N2O (53% N2O + 42% O2 + 5% N2), O2 (80% O2 + 20% N2) plus a control packed with air (21% O2 + 80% N2) and stored at 5 °C for 10 days. The gas concentrations inside the bags, E. coli and Enterobacteriaceae were periodically determined. The headspace gas composition inside the bags during storage changed mainly due to the respiration of the arugula leaves. The concentration of O2 decreased from 40% to 20-26% in the Ar, He and N2O enriched atmospheres, and from 80 to 58% in the O2 atmosphere treatment. The concentration of CO2 levels increased in all bags approximately to 20-23%, except in the bags with He which reached 10%. The Ar and He atmospheres were the most effective in reducing the count of E. coli (<5.0 log CFU·g-1) and Enterobacteriaceae (<7.0 log CFU·g-1) after 10 days. Novel gases Ar and He had the greater reduction in microbial growth on arugula leaves....
The aim of this study was to evaluate the effect of novel gases such as argon (Ar), helium (He), nitrous oxide (N2O), O2 and air, on Escherichia coli inoculated on arugula leaves (Eruca vesicaria). The samples were disinfected with sodium hypochlorite (95 mg·L-1, pH 6.5) and rinsed with sterile water; the leaves were inoculated with E. coli (6,5 log CFU·g-1) and packed in different atmospheres enriched with Ar (53% Ar + 41% O2 + 6% N2); He (53% He + 42% O2 + 5% N2); N2O (53% N2O + 42% O2 + 5% N2), O2 (80% O2 + 20% N2) plus a control packed with air (21% O2 + 80% N2) and stored at 5 °C for 10 days. The gas concentrations inside the bags, E. coli and Enterobacteriaceae were periodically determined. The headspace gas composition inside the bags during storage changed mainly due to the respiration of the arugula leaves. The concentration of O2 decreased from 40% to 20-26% in the Ar, He and N2O enriched atmospheres, and from 80 to 58% in the O2 atmosphere treatment. The concentration of CO2 levels increased in all bags approximately to 20-23%, except in the bags with He which reached 10%. The Ar and He atmospheres were the most effective in reducing the count of E. coli (<5.0 log CFU·g-1) and Enterobacteriaceae (<7.0 log CFU·g-1) after 10 days. Novel gases Ar and He had the greater reduction in microbial growth on arugula leaves....
Actualización de la herramienta de análisis integral para los niveles de toma de decisión estratégica, táctica y operativa de la ingeniería química
(Universidad de Chile, 2020)
Dentro de la industria de procesos los ingenieros se ven constantemente enfrentados a dilemas éticos pues sus decisiones pueden tener efectos, deseados y no deseados, sobre la sociedad y el medioambiente. Por lo anterior es que Richard Martínez, en...
¿Democracia sustantiva con estado mínimo? Los Derechos Sociales en el Neoliberalismo.
(Universidad de Chile, 2016)
predefinen los alcances y posibilidades de la democracia. Además, los alcances de la democracia repercuten en la noción misma de ciudadanía. Esta discusión se aborda mediante el estudio teórico de los derechos sociales, como dimensiones de los Derechos...
Oportunidad de inversión inmobiliaria, en el ámbito de una posible revitalización urbana en el centro histórico de Rancagua
(Universidad de Chile, 2019)
El tiempo ha demostrado que las ciudades son dinámicas y su transformación se debe, principalmente, a las políticas económicas y a los modelos de desarrollo subyacentes, los que derivan en las políticas gubernamentales. La flexibilidad asociada a lo...
Time has shown that cities are dynamic and their transformation is mainly due to economic policies and underlying development models, which are derived in government programs. The flexibility associated with this has caused the abandonment and deterioration of its historical downtowns, a situation that has been accelerated by phenomena like earthquakes. Despite this, many cities have undertaken reconversion, renovation and rehabilitation processes, which have had an impact on the urban revitalization of this kind of sector, whose integrality has been discussed. In Chile, there has been a program of state subsidies aimed at renovating the central neighborhoods of some cities, but in the larger intermediate cities there have not prospered. The research determines the factors that hinder the investment property of housing in the historic and urban center of an intermediate Chilean city. Then, with the determination and analysis of some urban attributes, a possible building proyect is defined, which can help as a reference and subsequent studies in this field....
Time has shown that cities are dynamic and their transformation is mainly due to economic policies and underlying development models, which are derived in government programs. The flexibility associated with this has caused the abandonment and deterioration of its historical downtowns, a situation that has been accelerated by phenomena like earthquakes. Despite this, many cities have undertaken reconversion, renovation and rehabilitation processes, which have had an impact on the urban revitalization of this kind of sector, whose integrality has been discussed. In Chile, there has been a program of state subsidies aimed at renovating the central neighborhoods of some cities, but in the larger intermediate cities there have not prospered. The research determines the factors that hinder the investment property of housing in the historic and urban center of an intermediate Chilean city. Then, with the determination and analysis of some urban attributes, a possible building proyect is defined, which can help as a reference and subsequent studies in this field....
Empoderamiento y autonomía de mujeres campesinas de Musa, Las Margaritas, Chiapas, México
(Universidad de Chile, 2013)
La importancia de la participación de las mujeres, campesinas e indígenas en espacios públicos considerados culturalmente sólo para los hombres, los recursos que facilitan su inserción a esos ámbitos y el conocimiento de los obstáculos que impiden...
Caracterización de bacteriófagos contra Pseudomonas syringae pv. tomato como parte de una estrategia de biocontrol de la Peca Bacteriana en cultivos de tomate
(Universidad de Chile, 2021-04)
Pseudomonas syringae patovar tomato es la bacteria fitopatógena causante de la Peca Bacteriana en tomates. Actualmente, el manejo de la enfermedad se basa en el control cultural y químico, con uso frecuente de pesticidas en base a cobre y...
Pseudomonas syringae pathovar tomato is the phytopathogenic bacterium that causes Bacterial Speck in tomatoes. Currently, the management of the disease is based on cultural and chemical control, with frequent use of pesticides based on copper and streptomycin. However, the abuse of these products has led to the selection of resistant bacteria, intensifying the development of alternative management strategies. In this regard, bacteriophages or phages have gained renewed interest as biological control agents due to their ability to exclusively infect and lyse bacteria, even those resistant to pesticides. The present study aimed to isolate and characterize phages as potential biocontrol agents of P. syringae pathovar tomato strains isolated from tomato crops in the Central Zone of Chile, some of them tolerant to pesticides. As a result, ten phages were isolated from sewage samples and an acequia, which were proceeded to characterize morphological and molecularly. Among their main characteristics, they all produced clear plaques, they lack lipid membrane, and their genomes are composed of double-stranded DNA. In addition to this, the morphologies observed by transmission electron microscopy determined that the ten phages belong to the Caudovirales order and possess the morphologies of the families Myoviridae (phages Φ1 and Φ16), Podoviridae (phages Φ11, Φ12, Φ15 and Φ18) and Siphoviridae (phages Φ7 and Φ8). Direct genome restriction enzyme analysis revealed that the phages are genetically diverse, distinguishing five clusters that are associated with morphology. Subsequently, the host range of the phages was determined by evaluating the ability to lyse 77 strains of P. syringae pathovar tomato. The phages lysed 44 strains, of which 41% are tolerant to copper, 9% to streptomycin and 30% to both pesticides. Also, the translocation capability of the phages through the roots of young tomato plants in a hydroponic medium was evaluated. For the tests, six phages were selected according to morphological diversity and, as a result, phages Φ6, Φ8, Φ12 and Φ18 were detected in stem and phage Φ1 also in leaves. Finally, this is the first study that reports the isolation and characterization of bacteriophages that infect P. syringae pathovar tomato strains isolated in Chile. The phages lysed 57% of strains, including copper and/or streptomycin tolerant strains. In addition, they are able to translocate in tomato plants from the roots into higher tissues. The results indicate the potential to be used in an effective biocontrol strategy against P. syringae pathovar tomato....
Pseudomonas syringae pathovar tomato is the phytopathogenic bacterium that causes Bacterial Speck in tomatoes. Currently, the management of the disease is based on cultural and chemical control, with frequent use of pesticides based on copper and streptomycin. However, the abuse of these products has led to the selection of resistant bacteria, intensifying the development of alternative management strategies. In this regard, bacteriophages or phages have gained renewed interest as biological control agents due to their ability to exclusively infect and lyse bacteria, even those resistant to pesticides. The present study aimed to isolate and characterize phages as potential biocontrol agents of P. syringae pathovar tomato strains isolated from tomato crops in the Central Zone of Chile, some of them tolerant to pesticides. As a result, ten phages were isolated from sewage samples and an acequia, which were proceeded to characterize morphological and molecularly. Among their main characteristics, they all produced clear plaques, they lack lipid membrane, and their genomes are composed of double-stranded DNA. In addition to this, the morphologies observed by transmission electron microscopy determined that the ten phages belong to the Caudovirales order and possess the morphologies of the families Myoviridae (phages Φ1 and Φ16), Podoviridae (phages Φ11, Φ12, Φ15 and Φ18) and Siphoviridae (phages Φ7 and Φ8). Direct genome restriction enzyme analysis revealed that the phages are genetically diverse, distinguishing five clusters that are associated with morphology. Subsequently, the host range of the phages was determined by evaluating the ability to lyse 77 strains of P. syringae pathovar tomato. The phages lysed 44 strains, of which 41% are tolerant to copper, 9% to streptomycin and 30% to both pesticides. Also, the translocation capability of the phages through the roots of young tomato plants in a hydroponic medium was evaluated. For the tests, six phages were selected according to morphological diversity and, as a result, phages Φ6, Φ8, Φ12 and Φ18 were detected in stem and phage Φ1 also in leaves. Finally, this is the first study that reports the isolation and characterization of bacteriophages that infect P. syringae pathovar tomato strains isolated in Chile. The phages lysed 57% of strains, including copper and/or streptomycin tolerant strains. In addition, they are able to translocate in tomato plants from the roots into higher tissues. The results indicate the potential to be used in an effective biocontrol strategy against P. syringae pathovar tomato....
Estudio técnico económico del proceso de extracción de florotaninos desde M. pyrifera
(Universidad de Chile, 2018)
consistió en realizar balances de masa y energía a partir de un caso base de producción, para dimensionar los equipos requeridos y posteriormente analizarlo económicamente. Además, se seleccionaron variables a sensibilizar para concluir acerca de la...
Deducibilidad de los gastos por concepto de responsabilidad social empresarial
(Universidad de Chile, 2018-10)
internacional para evaluar la responsabilidad social de
proveedores y vendedores. La norma SA8000 provee los requisitos y la metodología
para evaluar las condiciones en los lugares de trabajo incluyendo el trabajo infantil,
la fuerza de trabajo, la seguridad...
Investigación y Desarrollo………………...…….......14 6.3.3. Inversión en Zonas Extremas……………………………............15 6.3.4. Donaciones Culturales, Deportivas en Fundaciones y Corporaciones…………………………………………….……...16 7. El proyecto de reglamento de los acuerdos...
Investigación y Desarrollo………………...…….......14 6.3.3. Inversión en Zonas Extremas……………………………............15 6.3.4. Donaciones Culturales, Deportivas en Fundaciones y Corporaciones…………………………………………….……...16 7. El proyecto de reglamento de los acuerdos...
Propuesta de un modelo de cooperativa en comunidades aisladas para electrificación rural económica: mediante sistema modular de energías renovables, eólico y solar
(Universidad de Chile, 2018)
El acceso a fuentes energéticas estables, continuas y seguras es un requisito mínimo para asegurar una calidad de vida, existen en Chile más de 20 mil familias de sectores rurales sin acceso de ningún tipo a la energía eléctrica, lo cual es un...
Caracterización de atributo que agregan valor al aceite de oliva según consumidor
(Universidad de Chile, 2014)
En el mundo, el consumo de aceites de semilla, se masificó como un importante producto gastronómico cuyo uso varía entre un vegetal y otro de acuerdo a su accesibilidad y precio. Dado que hoy el consumidor de aceite se siente atraído por un producto...
Worldwide, consumption of seed oils, are massified as an important gastronomic product whose use varies between a vegetable and another according to their accessibility and price. Given that today's consumer is attracted to oil as a functional product, is that there has been a large increase in the consumption of olive oil. In response, the industry has established Chilean olive production quality products worldwide’s recognized, using the soil and climate in the country. This study aimed to learn about aspects of the olive oil market from a consumer perspective. A survey was applied to a nonrandomized probability sample of 400 consumers from La Florida commune, Metropolitan Region of Chile. The data were analyzed using multivariate methods, specifically main component analysis, cluster analysis and conjoint analysis. In addition, variables related with descriptive aspects of consumption, sociodemographic characteristics, In addition, variables were analyzed with descriptive aspects regarding purchase and consumption of olive oil, and sociodemographic characteristics. Moreover, analysis of market shares was performed, with the price sensitivity that both segments have was observed....
Worldwide, consumption of seed oils, are massified as an important gastronomic product whose use varies between a vegetable and another according to their accessibility and price. Given that today's consumer is attracted to oil as a functional product, is that there has been a large increase in the consumption of olive oil. In response, the industry has established Chilean olive production quality products worldwide’s recognized, using the soil and climate in the country. This study aimed to learn about aspects of the olive oil market from a consumer perspective. A survey was applied to a nonrandomized probability sample of 400 consumers from La Florida commune, Metropolitan Region of Chile. The data were analyzed using multivariate methods, specifically main component analysis, cluster analysis and conjoint analysis. In addition, variables related with descriptive aspects of consumption, sociodemographic characteristics, In addition, variables were analyzed with descriptive aspects regarding purchase and consumption of olive oil, and sociodemographic characteristics. Moreover, analysis of market shares was performed, with the price sensitivity that both segments have was observed....