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Características de la canal y de la carne de corderos de raza Merino Precoz: efecto del peso de sacrificio
(Universidad de Chile, 2008)
El objetivo de la presente memoria de título fue evaluar el efecto del peso de sacrificio sobre las características de la canal y de la calidad de la carne de corderos de raza Merino Precoz. Con este propósito se emplearon 36 corderos machos Merino...
Concepto de biofilia en educación inicial
(Universidad de Chile, 2017-10-19)
Esta investigación pretende reflejar cómo se visualiza y trabaja el concepto de biofilia en el nivel de transición 2 de dos colegios particulares de la Región Metropolitana que difieren en sus ambientes de aprendizaje (presencia/ausencia de...
Interrelaciones de la segregación socio espacial con los impactos territoriales de las recientes crisis (estallido social y pandemia COVID-19) : estudio de la RM 2017-2020
(Universidad de Chile, 2021)
La segregación socio espacial es un fenómeno estructural y de largo aliento que ha sido identificado por la PNDU y otras políticas como un elemento nocivo para las ciudades. A pesar de ello, no han existido a la fecha actual instrumentos claros de...
"Chile y la inversión extranjera : análisis de casos CIADI"
(Universidad de Chile, 2014)
UNIVERSIDAD DE CHILE
ESCUELA DE DERECHO
DEPARTAMENTO DE DERECHO INTERNACIONAL
“CHILE Y LA INVERSION EXTRANJERA: ANÁLISIS DE
CASOS CIADI”
Memoria para optar al grado de Licenciado en Ciencias Jurídicas y...
Sociales. PABLO ANDRÉS MAHU MARTÍNEZ y MAXIMILIANO JOSÉ ROJAS CONEJERO Profesor guía: Eduardo Picand Albónico. Santiago de Chile Mayo de 2014 Quisiéramos agradecer al profesor por su dedicación y colaboración incondicional. A Elcira, Nelly...
Sociales. PABLO ANDRÉS MAHU MARTÍNEZ y MAXIMILIANO JOSÉ ROJAS CONEJERO Profesor guía: Eduardo Picand Albónico. Santiago de Chile Mayo de 2014 Quisiéramos agradecer al profesor por su dedicación y colaboración incondicional. A Elcira, Nelly...
Síntesis y caracterización de dióxido de manganeso y silicatos de calcio nano-estructurados con propiedades magnéticas a emplear como adsorbentes de contaminantes inorgánicos desde soluciones acuosas que simulan aguas ácidas de mina
(Universidad de Chile, 2017)
En esta investigación se estudió la síntesis y caracterización de nuevos adsorbentes de bajo costo correspondientes a dióxido de manganeso con propiedades magnéticas (mag-MnO2) y silicatos de calcio nano-estructurados magnetizados (mag...
The synthesis and characterization of new low-cost adsorbents corresponding to manganese dioxide with magnetics properties (mag-MnO2) and magnetized nano-structured calcium silicates (mag-NanoSCH) were studied. These adsorbents were applied in acid aqueous solutions in order to remove some inorganic contaminants normally found in mine waters. The synthesis of mag-MnO2 was accomplished by the chemical reaction of KMnO4, MnCl2, KOH and the addition of magnetite, which gives to it magnetic properties. The synthesis of mag-NanoSCH was conducted by means of the chemical reaction between Ca(OH)2 an aqueous solution of sodium silicate (Na2SiO3) and magnetite. In this particular case, two composites were synthetized in two proportions, 1:1 and 2:1 in rate to NanoSCH/Fe3O4. The synthesis was fast, efficient and reproducible. The adsorbents were characterized using different methodologies. These results show that they possess a crystalline nucleus formed by magnetite and a cover of amorphous characteristics having tendency to the particles agglomeration. Moreover, they present a great reasonable high surface area that generate a structure with a large number of active sites available to be adsorbed. The magnetic saturation showed by VSM was high enough for the adsorbents, which ensured an efficient separation of them from the refine. The adsorbents presented an adequate chemical stability towards acid aqueous solutions. The adsorbent mag-MnO2 presented an excellent behavior for adsorbing the metallic ions Pb2+, Cd2+, Cu2+ y Zn2+ at pH higher than 3.0 through a mechanism of ion exchange between the metal ionic and H+ existent in the surface of the adsorbent. Regarding to the anionic species (arsenates and molybdates), the adsorption is favored at pH ≤ 2 through a mechanism of electrostatic attraction and the formation of ionic pairs. Tests of equilibrium and kinetics adsorption were carried out with the adsorbent mag-MnO2, for the metal ions and the oxyanion. In tests of equilibrium, high values of qmax were obtained for most of the adsorbates and the experimental results adjusted well the Langmuir model when mono-elemental solutions were used. However, when more complex and real aqueous matrices are utilized, experimental data are best fitted using Freundlich isotherm. The initial kinetics of adsorption was fast for almost all the contaminants, whose results were well explained for a pseudo-second-order kinetic model. Additionally, the possibility of reusing the adsorbent in more than one adsorption cycle was studied. In this sense, it was determined that contacting the adsorbent charged with the removed contaminants with and acid aqueous solution of pH 2.0, a high grade of desorption was achieved, which enabled the reuse of the adsorbent in at least four cycles of adsorption-desorption, without a significant loss of adsorption capacity. The composite mag-MnO2 could effectively remove in a collective way the metal ions and anionic species existent in multicomponent aqueous solutions. The hydrometallurgical exploratory tests using the magnetized nano-structured calcium silicates showed a great adsorption capacity that these adsorbents present, both NanoSCH/Fe3O4 1:1 and 2:1. They presented an effective behavior for aqueous solutions of pH among 1.0 to 6.0, being measured high percentages of adsorption and loading capacities for all the ionic species that were studied. The use of both types of adsorbents prepared in this study, in a consecutive way, first NanoSCH/Fe3O4 followed of use of mag-MnO2, for treating an aqueous matrix that simulate an acidic mine water containing multiple contaminants in different concentrations was highly efficient. In a practical way, were obtained refines whose final contents of the main components accomplish with the environmental norm described in the supreme decree 90/2000 of Chilean government concerning water discharge in fluvial bodies...
The synthesis and characterization of new low-cost adsorbents corresponding to manganese dioxide with magnetics properties (mag-MnO2) and magnetized nano-structured calcium silicates (mag-NanoSCH) were studied. These adsorbents were applied in acid aqueous solutions in order to remove some inorganic contaminants normally found in mine waters. The synthesis of mag-MnO2 was accomplished by the chemical reaction of KMnO4, MnCl2, KOH and the addition of magnetite, which gives to it magnetic properties. The synthesis of mag-NanoSCH was conducted by means of the chemical reaction between Ca(OH)2 an aqueous solution of sodium silicate (Na2SiO3) and magnetite. In this particular case, two composites were synthetized in two proportions, 1:1 and 2:1 in rate to NanoSCH/Fe3O4. The synthesis was fast, efficient and reproducible. The adsorbents were characterized using different methodologies. These results show that they possess a crystalline nucleus formed by magnetite and a cover of amorphous characteristics having tendency to the particles agglomeration. Moreover, they present a great reasonable high surface area that generate a structure with a large number of active sites available to be adsorbed. The magnetic saturation showed by VSM was high enough for the adsorbents, which ensured an efficient separation of them from the refine. The adsorbents presented an adequate chemical stability towards acid aqueous solutions. The adsorbent mag-MnO2 presented an excellent behavior for adsorbing the metallic ions Pb2+, Cd2+, Cu2+ y Zn2+ at pH higher than 3.0 through a mechanism of ion exchange between the metal ionic and H+ existent in the surface of the adsorbent. Regarding to the anionic species (arsenates and molybdates), the adsorption is favored at pH ≤ 2 through a mechanism of electrostatic attraction and the formation of ionic pairs. Tests of equilibrium and kinetics adsorption were carried out with the adsorbent mag-MnO2, for the metal ions and the oxyanion. In tests of equilibrium, high values of qmax were obtained for most of the adsorbates and the experimental results adjusted well the Langmuir model when mono-elemental solutions were used. However, when more complex and real aqueous matrices are utilized, experimental data are best fitted using Freundlich isotherm. The initial kinetics of adsorption was fast for almost all the contaminants, whose results were well explained for a pseudo-second-order kinetic model. Additionally, the possibility of reusing the adsorbent in more than one adsorption cycle was studied. In this sense, it was determined that contacting the adsorbent charged with the removed contaminants with and acid aqueous solution of pH 2.0, a high grade of desorption was achieved, which enabled the reuse of the adsorbent in at least four cycles of adsorption-desorption, without a significant loss of adsorption capacity. The composite mag-MnO2 could effectively remove in a collective way the metal ions and anionic species existent in multicomponent aqueous solutions. The hydrometallurgical exploratory tests using the magnetized nano-structured calcium silicates showed a great adsorption capacity that these adsorbents present, both NanoSCH/Fe3O4 1:1 and 2:1. They presented an effective behavior for aqueous solutions of pH among 1.0 to 6.0, being measured high percentages of adsorption and loading capacities for all the ionic species that were studied. The use of both types of adsorbents prepared in this study, in a consecutive way, first NanoSCH/Fe3O4 followed of use of mag-MnO2, for treating an aqueous matrix that simulate an acidic mine water containing multiple contaminants in different concentrations was highly efficient. In a practical way, were obtained refines whose final contents of the main components accomplish with the environmental norm described in the supreme decree 90/2000 of Chilean government concerning water discharge in fluvial bodies...
El best seller literario en Chile: (2006-2010)
(Universidad de Chile, 2012)
En una realidad en la que la tecnología empieza a tomar protagonismo, las transformaciones en los productos culturales son inevitables. El libro es un objeto por el que se lucha para que no deje de existir y se mantenga el valor simbólico que ha...
Recubrimiento de nanoesferas de oro conjugadas al péptido CLPFFD-NH2 con poloxámeros para mejorar la penetración a través de membranas biológicas
(Universidad de Chile, 2014)
En la actualidad existe gran interés en el uso de nanopartículas esféricas de oro (NPAu) para aplicaciones biomédicas. Éstas presentan propiedades ópticas que permiten la absorción y disipación de energía de manera local en forma de calor luego de...
Nowadays, there exists a great interest in the use of spherical gold nanoparticles (NPAu) for biomedical applications. NPAu have optical properties that allow the absorption and local dissipation of energy in the form of heating after being irradiated, which can be used to destroy tumoral cells or dissolve ammiloid-β toxic protein aggregates (ATAβ) that are involved in the Alzheimer disease (EA). In our laboratory, NPAu were conjugated with the CLPFFD-NH2 peptide which recognizes ATAβ, forming the NPAu-CLPFFD conjugate. These aggregates can be dissolved in the presence of NPAu-CLPFFD through the application of weak microwaves fields, decreasing their toxicity. However, the NPAu-CLPFFD conjugate crosses the blood brain barrier (BHE) in very small proportion with respect to the dose injected. The main focus of this study was the coating of NPAu-CLPFFD by amphiphilic polymers such as poloxamers (Pluronics®) to facilitate the cross throughout the BHE. These copolymers have demonstrated the capacity to inhibit efflux transporter expressed in different types of cells and also modify the fluidity of model membranes. In this study, three copolymers were used which differ in their structural properties: Pluronic® P85, F127 y L121, where their hydrophilic lipophilic balances (HLB) are 16, 22 and 1, respectively. The nanocomposites were characterized through molecular absorption spectrophotometry, dynamic light scattering (DLS), zeta potential, transmission electronic microscopy (TEM) and thermogravimetry. Also, changes in the stability and permeability of membrane models due to the interaction with nanocomposites, and the capacity of these to cross passively through the parallel artificial membrane permeability assay (PAMPA), were evaluated in vitro. In this way, it was determined that these nanocomposites are capable of modify biological membrane model stability and permeability possibly due to changes in their organization. Despite this, these systems were not capable to improve the cross of NPAu through passive diffusion in the PAMPA...
Nowadays, there exists a great interest in the use of spherical gold nanoparticles (NPAu) for biomedical applications. NPAu have optical properties that allow the absorption and local dissipation of energy in the form of heating after being irradiated, which can be used to destroy tumoral cells or dissolve ammiloid-β toxic protein aggregates (ATAβ) that are involved in the Alzheimer disease (EA). In our laboratory, NPAu were conjugated with the CLPFFD-NH2 peptide which recognizes ATAβ, forming the NPAu-CLPFFD conjugate. These aggregates can be dissolved in the presence of NPAu-CLPFFD through the application of weak microwaves fields, decreasing their toxicity. However, the NPAu-CLPFFD conjugate crosses the blood brain barrier (BHE) in very small proportion with respect to the dose injected. The main focus of this study was the coating of NPAu-CLPFFD by amphiphilic polymers such as poloxamers (Pluronics®) to facilitate the cross throughout the BHE. These copolymers have demonstrated the capacity to inhibit efflux transporter expressed in different types of cells and also modify the fluidity of model membranes. In this study, three copolymers were used which differ in their structural properties: Pluronic® P85, F127 y L121, where their hydrophilic lipophilic balances (HLB) are 16, 22 and 1, respectively. The nanocomposites were characterized through molecular absorption spectrophotometry, dynamic light scattering (DLS), zeta potential, transmission electronic microscopy (TEM) and thermogravimetry. Also, changes in the stability and permeability of membrane models due to the interaction with nanocomposites, and the capacity of these to cross passively through the parallel artificial membrane permeability assay (PAMPA), were evaluated in vitro. In this way, it was determined that these nanocomposites are capable of modify biological membrane model stability and permeability possibly due to changes in their organization. Despite this, these systems were not capable to improve the cross of NPAu through passive diffusion in the PAMPA...
Evaluación de la respuesta inmune protectora contra Metapneumovirus humano inducida por el prototipo de vacuna compuesto por la nucleoproteína N más el adyuvante AbISCO-100
(Universidad de Chile, 2016)
El Metapneumovirus humano (hMPV) es el segundo agente viral causante de bronquiolitis en niños de todo el mundo. Es el origen etiológico de variados cuadros clínicos del tracto respiratorio y afecto principalmente a niños y ancianos. La infección...
Worldwide, human Metapneumovirus (hMPV) is the second cause of acute respiratory tract infection in children such as bronchiolitis and pneumonia. It is the etiological origin of several clinical manifestations of the respiratory tract and mainly affects children and the elderly. The hMPV infection has been associated with an unbalanced Th2 pathological response causing inflammation and obstruction in the respiratory tract. Because a poor immunological memory induction is developed, the airway infections with hMPV and disease associated are recurrent. In consequence, an hMPV vaccine that generates protective immune response is necessary. To date there is no effective vaccine available against this virus. This study shows that vaccinated mice with N-hMPV-ABISCO developed a protective immune response against hMPV infection. Compared to non-vaccinated mice, we measured a reduction in the transcripts of the N gene of hMPV in lungs and a reduction in weight loss in vaccinated mice. Besides, in these mice there is a decrease of granulocyte infiltration and of dendritic cell infiltration of conventional migratory DCs (CD11b-/CD11c+) in lungs. Moreover, we isolated splenocytes from vaccinated and non-vaccinated mice and stimulated these cells with recombinant N protein of hMPV. The induced cytokines was measured in the supernatant tissue culture medium. We observed an increase of IFN-γ, IL-10 and IL-17A in splenocytes obtained from vaccinated mice. Total and IgG subclasses was measured in serum and higher levels of IgG and IgG2a were detected in the serum of vaccinated and challenged mice compared to naïve mice. The results obtained in this investigation suggest that the vaccinated mice developed a protective T cell-mediated immune response with a combined Th1 / Th17 profile that protected them against infection with hMPV and its associated pathology and that N protein could be a good candidate for a vaccine...
Worldwide, human Metapneumovirus (hMPV) is the second cause of acute respiratory tract infection in children such as bronchiolitis and pneumonia. It is the etiological origin of several clinical manifestations of the respiratory tract and mainly affects children and the elderly. The hMPV infection has been associated with an unbalanced Th2 pathological response causing inflammation and obstruction in the respiratory tract. Because a poor immunological memory induction is developed, the airway infections with hMPV and disease associated are recurrent. In consequence, an hMPV vaccine that generates protective immune response is necessary. To date there is no effective vaccine available against this virus. This study shows that vaccinated mice with N-hMPV-ABISCO developed a protective immune response against hMPV infection. Compared to non-vaccinated mice, we measured a reduction in the transcripts of the N gene of hMPV in lungs and a reduction in weight loss in vaccinated mice. Besides, in these mice there is a decrease of granulocyte infiltration and of dendritic cell infiltration of conventional migratory DCs (CD11b-/CD11c+) in lungs. Moreover, we isolated splenocytes from vaccinated and non-vaccinated mice and stimulated these cells with recombinant N protein of hMPV. The induced cytokines was measured in the supernatant tissue culture medium. We observed an increase of IFN-γ, IL-10 and IL-17A in splenocytes obtained from vaccinated mice. Total and IgG subclasses was measured in serum and higher levels of IgG and IgG2a were detected in the serum of vaccinated and challenged mice compared to naïve mice. The results obtained in this investigation suggest that the vaccinated mice developed a protective T cell-mediated immune response with a combined Th1 / Th17 profile that protected them against infection with hMPV and its associated pathology and that N protein could be a good candidate for a vaccine...
Desarrollo de la actividad física y deportiva, fomento público y responsabilidad social empresarial
(Universidad de Chile, 2014)
El deporte debemos entenderlo, no sólo como una actividad lúdica y de esparcimiento, que debe ser realizada en momentos de “ocio” por los individuos, sino también es importante señalar que el deporte es un derecho que todo ser humano debiera poder...
Significados de la experiencia de terremoto y tsunami del 27 de Febrero de 2010 en un grupo de niños y niñas de la comuna de Paredones, VI Región, a través de sus narrativas
(Universidad de Chile, 2012)
El presente trabajo pretende observar con detenimiento los significados que le dan un grupo de niños y niñas de la Comuna de Paredones, al terremoto del 27/F y sus posibles elementos traumáticos, a través de las narrativas que se construyen en la...