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Mejorando la calidad educativa de los niños vulnerables: una propuesta aplicada al caso de Chile
(Universidad de Chile, 2013-01)
en la implementación de un sello de calidad que acredite a los profesores a trabajar con niños vulnerables. Para lograr dicha certificación es necesario que los docentes aprueben una evaluación, que llamaremos INICIA 2.0, la cual constará de las...
El método fenomenológico. Aplicación de la poché al sentido absoluto de la conciencia.
(Universidad de Chile. Facultad de Ciencias Sociales, 1998-04)
conciencia desarrollado en Ideas Relativas a una Fenomenología Pura y una Filosofía Fenomenológica (en adelante Ideas); esto permitirá mostrar cómo Husserl aplica la epoché al tema de la conciencia. Es decir, más que una investigación acerca del sentido...
Impactos potenciales en los recursos territoriales del Fiordo Comau asociados a una obra de conectividad estratégica : la Carretera Austral
(Universidad de Chile, 2019)
proyecto de infraestructura vial para ampliar la Ruta CH-7, con un tramo que está proyectado a lo largo de la zona oriental del fiordo. Se prevé que esta obra repercutirá en la valoración uso de los recursos naturales y territoriales del área...
The Comau fjord, located in the Los Lagos Region in the Chilean nordpatagonia, has a great terrestrial biodiversity, but especially marine, which shows high levels of endemism and environmental fragility. A road infrastructure project has been initiated to expand the Route CH-7, with a section that is projected along the eastern part of the fjord. It is expected that this road work will impact on the valuation and the use of natural and territorial resources of the area, mainly in marine areas, due to the incentive that this substancial improvement in road connectivity will mean for the aquaculture industry. Likewise, it will generate demographic changes and an increase in tourism, phenomena that will affect the use and consumption of the territory's resources, generating unfavorable impacts for the local biota....
The Comau fjord, located in the Los Lagos Region in the Chilean nordpatagonia, has a great terrestrial biodiversity, but especially marine, which shows high levels of endemism and environmental fragility. A road infrastructure project has been initiated to expand the Route CH-7, with a section that is projected along the eastern part of the fjord. It is expected that this road work will impact on the valuation and the use of natural and territorial resources of the area, mainly in marine areas, due to the incentive that this substancial improvement in road connectivity will mean for the aquaculture industry. Likewise, it will generate demographic changes and an increase in tourism, phenomena that will affect the use and consumption of the territory's resources, generating unfavorable impacts for the local biota....
Caracterización del mecanismo de plegamiento de una versión monomérica del represor AR, un miembro de la superfamilia RHH con topología anudada, mediante espectroscopia de fuerza de trampa óptica
(Universidad de Chile, 2014)
La topología de una proteína, definida como el camino tridimensional que sigue la cadena polipeptídica en el espacio, impone restricciones naturales al conjunto de movimientos que esta puede realizar para alcanzar su estado nativo. Por esta razón...
The topology of a protein, defined as the tridimensional path of the polypeptide chain in space, restricts the moves that the chain can perform for searching its native state. For this reason this property defines the folding mechanism of a protein. However, in recent years has been discovered some proteins that seek their native states through complex and intricate movements. Such is the case of knotted proteins which topology challenge current theories of protein folding and have opened new questions about protein folding mechanisms. The first knotted structure was identified in 2000, since then many others have been discovered reaching the 2% of the structures in the Protein data bank (PDB). The low relative abundance of the knotted structures contrast with simulation of polymer models showing that knotted structures are easy to exist in those systems. This suggests that proteins somehow have avoided knotted topologies. Another interesting thing to investigate about knotted proteins is the function that may have the knotted topology on this proteins and how that structures may fold. It has been determined that some knotted motifs are conserved in families and superfamilies despite of the low sequence identity. These results suggest that knotted motifs could provide some comparative advantage with respect to normal proteins. In this regard some theoretical and experimental evidence show that knotted topologies could enhance the stability of proteins. Nevertheless, none of these studies explain how this topologies does it. In this work we seek to elucidate the energetic consequence that brings the knotting of a polypeptide chain to its folding mechanism. For this, we compare the folding process of a knotted protein with their unknotted counterpart. In terms of experimental approach this problem impose two challenges, the first one is that the knot formation should don’t disturb the structure of the protein. The second one is that we must control de topology of the unfolded state in order to ensure the homogeneity of the thermodynamic species under experimentation. The first challenge was archived using the mARC protein from the RHH superfamily of transcription factors. This protein is a monomeric version of the ARC repressor from the p22 phage and it was constructed connecting the C terminus of the first subunit to the N terminus of the next one using a 15 residue glycine-rich polypeptide linker. Structural models mARC shows that the linker forms a flexible loop that doesn’t form contacts with hydrophobic core of the protein. Moreover, homology models indicate that the loop can move around the protein generating two conformations: a knotted and an unknotted one. The second challenge was addressed by characterizing the folding mechanism of mARC using optical tweezers. This approximation allows us to pull the protein from its C and N-terminal ends to control the topology of the unfolded state and thus to compare the energy differences between the knotted unfolded state and the unknotted unfolded state of mARC. In the other hand, by a rearrangement of the secondary structure of mARC it is possible to generate a non-cyclic permutant, pARC. This protein is reported to have the same architecture and folding stability of mARC but, its topology prevents knotting. So, pARC was used as a topological control of the effect of knotting the mARC protein. We found that mARC can be captured in two conformations characterized by different contour length (L0, total extension of a polymer chain). One group of molecules has a L0 of 43 ± 7 nm and corresponds to the expected for the unknotted conformation of mARC. The other group of molecules shows a L0 of 37 ± 7 nm and corresponds to the expected for the knotted conformation. On the contrary pARC only shows one type of molecules characterized by a L0 of 22 ± 7 nm. All together these results support the hypothesis that mARC is present in two conformations, one knotted and other unknotted. Moreover, applying Crook’s theorem to the irreversible work associated to the unfolding and refolding transitions of mARC and pARC allowed to determine the free energy (ΔG) at equilibrium required to the unfold the knotted (ΔG1= 21,8 ± 0,4 kcal/mol), unknotted (ΔG2= 12,3 ± 0,5 kcal/mol) conformations of mARC and pARC (ΔG3= 7 ± 0,4 kcal/mol). These results indicate that knotted mARC is more stable than their unknotted counterpart by 8,9 ± 0,9 kcal/mol mainly due to the energetic cost to tie the unfolded state of the protein. This value corresponds to the energetic cost of knotting a polypeptide chain of 120 residues in its unfolded state and explains the source of the stabilizing effect of the knotted topology in mARC. For the kinetic characterization we performed constant force experiments. It was only possible to study two molecules of mARC. Despite of the differences between the kinetic parameters calculated for them, both corresponds to the unknotted conformation of the protein...
The topology of a protein, defined as the tridimensional path of the polypeptide chain in space, restricts the moves that the chain can perform for searching its native state. For this reason this property defines the folding mechanism of a protein. However, in recent years has been discovered some proteins that seek their native states through complex and intricate movements. Such is the case of knotted proteins which topology challenge current theories of protein folding and have opened new questions about protein folding mechanisms. The first knotted structure was identified in 2000, since then many others have been discovered reaching the 2% of the structures in the Protein data bank (PDB). The low relative abundance of the knotted structures contrast with simulation of polymer models showing that knotted structures are easy to exist in those systems. This suggests that proteins somehow have avoided knotted topologies. Another interesting thing to investigate about knotted proteins is the function that may have the knotted topology on this proteins and how that structures may fold. It has been determined that some knotted motifs are conserved in families and superfamilies despite of the low sequence identity. These results suggest that knotted motifs could provide some comparative advantage with respect to normal proteins. In this regard some theoretical and experimental evidence show that knotted topologies could enhance the stability of proteins. Nevertheless, none of these studies explain how this topologies does it. In this work we seek to elucidate the energetic consequence that brings the knotting of a polypeptide chain to its folding mechanism. For this, we compare the folding process of a knotted protein with their unknotted counterpart. In terms of experimental approach this problem impose two challenges, the first one is that the knot formation should don’t disturb the structure of the protein. The second one is that we must control de topology of the unfolded state in order to ensure the homogeneity of the thermodynamic species under experimentation. The first challenge was archived using the mARC protein from the RHH superfamily of transcription factors. This protein is a monomeric version of the ARC repressor from the p22 phage and it was constructed connecting the C terminus of the first subunit to the N terminus of the next one using a 15 residue glycine-rich polypeptide linker. Structural models mARC shows that the linker forms a flexible loop that doesn’t form contacts with hydrophobic core of the protein. Moreover, homology models indicate that the loop can move around the protein generating two conformations: a knotted and an unknotted one. The second challenge was addressed by characterizing the folding mechanism of mARC using optical tweezers. This approximation allows us to pull the protein from its C and N-terminal ends to control the topology of the unfolded state and thus to compare the energy differences between the knotted unfolded state and the unknotted unfolded state of mARC. In the other hand, by a rearrangement of the secondary structure of mARC it is possible to generate a non-cyclic permutant, pARC. This protein is reported to have the same architecture and folding stability of mARC but, its topology prevents knotting. So, pARC was used as a topological control of the effect of knotting the mARC protein. We found that mARC can be captured in two conformations characterized by different contour length (L0, total extension of a polymer chain). One group of molecules has a L0 of 43 ± 7 nm and corresponds to the expected for the unknotted conformation of mARC. The other group of molecules shows a L0 of 37 ± 7 nm and corresponds to the expected for the knotted conformation. On the contrary pARC only shows one type of molecules characterized by a L0 of 22 ± 7 nm. All together these results support the hypothesis that mARC is present in two conformations, one knotted and other unknotted. Moreover, applying Crook’s theorem to the irreversible work associated to the unfolding and refolding transitions of mARC and pARC allowed to determine the free energy (ΔG) at equilibrium required to the unfold the knotted (ΔG1= 21,8 ± 0,4 kcal/mol), unknotted (ΔG2= 12,3 ± 0,5 kcal/mol) conformations of mARC and pARC (ΔG3= 7 ± 0,4 kcal/mol). These results indicate that knotted mARC is more stable than their unknotted counterpart by 8,9 ± 0,9 kcal/mol mainly due to the energetic cost to tie the unfolded state of the protein. This value corresponds to the energetic cost of knotting a polypeptide chain of 120 residues in its unfolded state and explains the source of the stabilizing effect of the knotted topology in mARC. For the kinetic characterization we performed constant force experiments. It was only possible to study two molecules of mARC. Despite of the differences between the kinetic parameters calculated for them, both corresponds to the unknotted conformation of the protein...
Silvicultura en bosques nativos. Avances en la investigación en Chile, Argentina y Nueva Zelandia
(Marisa Cuneo Ediciones, 2013)
................................................................................................................................ 17
2 Propuesta silvicultural para el manejo sustentable
con fines industriales en bosques naturales con quillay
(Quillaja saponaria) en Chile central Gustavo Cruz...
y herramientas de gestión para la silvicultura en Chile .......................................................................................................................... 107 6 Biometría de los bosques naturales de Chile: estado del arte...
y herramientas de gestión para la silvicultura en Chile .......................................................................................................................... 107 6 Biometría de los bosques naturales de Chile: estado del arte...
Análisis de discurso a medios de comunicación digitales en Chile respecto al cambio climático : encuadres para la construcción de las agendas pública y política
(Universidad de Chile, 2014)
El estudio de caso busca conocer la forma en que los medios digitales representan el cambio climático en Chile, poniendo énfasis en la mitigación, adaptación y resiliencia. Chile es uno de los países más expuestos del mundo a los desastres naturales...
Inventario de geositios en la comuna de Lonquimay, para la creación del Geoparque Kütralkura, IX Región de la Araucanía
(Universidad de Chile, 2013)
El estudio y la conservación del geopatrimonio constituyen uno de los ámbitos de acción más recientes en la geología. En el transcurso de las últimas décadas, la conciencia respecto de su importancia se ha desarrollado con fuerza y diversos estudios...
Evolución de la economía en Occidente. De la ética del trabajo al afán de lucro
(Universidad Alberto Hurtado, 2004)
. Dentro de ese enfoque espiritual, la
consecución de algún tipo de ganancia a través del trabajo era secundaria y
considerada un premio a un comportamiento debido. El Capitalismo de Mer-
cado Autorregulado sigue esa misma concepción en un principio. Luego...
productivo que había dominado Occidente (y en su espíritu general también otras partes del globo). Durante aproximadamente dieciséis siglos de la historia * Antropólogo. Profesor del Departamento de Estudios Humanísticos de la Facultad de Ciencias Físicas y...
productivo que había dominado Occidente (y en su espíritu general también otras partes del globo). Durante aproximadamente dieciséis siglos de la historia * Antropólogo. Profesor del Departamento de Estudios Humanísticos de la Facultad de Ciencias Físicas y...
Caracterización de sistemas productivos lecheros de pequeños productores de un servicio de asesoría técnica en la Región del Libertador General Bernardo O’Higgins.
(UNIVERSIDAD DE CHILE, 2017)
, pues les significa pérdida de leche. A su vez, gran parte de los productores realiza tratamiento propio de la mastitis, ya sea porque aprendió en cursos de capacitación u observando al médico veterinario. En términos organizacionales, gran parte de los...
A study was carried out in small dairy producers from the Libertador Bernardo O'Higgins Region, Chile, to characterize their production systems. A semi-structured survey was applied to 25 small dairy producers from a technical program that belongs to the Instituto de Desarrollo Agropecuario (INDAP), corresponding to the total of small dairy farmers advised by ProAgro Consultores. The results were analyzed based on descriptive statistics, highlighting: the percentage of dairies managed by men was higher than those of women, the average age of the producers was 57 years, who are predominantly landowners who work with complementary activities to its main item. Producers work mainly with Holstein and Holstein mixed breeds, most milking only once a day and using stainless steel containers for milk storage, being the predominant destination their own cheese production. The producers keep track of reproductive and herd records, mainly. The reproductive management used are artificial insemination, pregnancy diagnosis and heat detection, being the heat synchronization the less used management. There are also other managements such as animal dehorning, a management made by most producers before six months of age, being the use of a cutting saw the most used method, followed by cut through of scissors. On the other hand, mastitis was named like the most common disease, as it means loss of milk production. In turn, an important fraction of the producers does their own mastitis treatments, either because they learned in training courses or by observing the veterinarian. In organizational terms, most producers are not linked to any organization, mainly because of mistrust. Producers identify their animals as the most important positive aspect of their productive system, whereas infrastructure was the most substantial negative aspect of it. Most of the producers consider that their productive system is relevant for the area where they belong, which they believe turn into a high local demand. The results of this work are limited to establish an integral characterization of the study population, yet they provide general features based on the experience of small producers, which may be useful for further studies....
A study was carried out in small dairy producers from the Libertador Bernardo O'Higgins Region, Chile, to characterize their production systems. A semi-structured survey was applied to 25 small dairy producers from a technical program that belongs to the Instituto de Desarrollo Agropecuario (INDAP), corresponding to the total of small dairy farmers advised by ProAgro Consultores. The results were analyzed based on descriptive statistics, highlighting: the percentage of dairies managed by men was higher than those of women, the average age of the producers was 57 years, who are predominantly landowners who work with complementary activities to its main item. Producers work mainly with Holstein and Holstein mixed breeds, most milking only once a day and using stainless steel containers for milk storage, being the predominant destination their own cheese production. The producers keep track of reproductive and herd records, mainly. The reproductive management used are artificial insemination, pregnancy diagnosis and heat detection, being the heat synchronization the less used management. There are also other managements such as animal dehorning, a management made by most producers before six months of age, being the use of a cutting saw the most used method, followed by cut through of scissors. On the other hand, mastitis was named like the most common disease, as it means loss of milk production. In turn, an important fraction of the producers does their own mastitis treatments, either because they learned in training courses or by observing the veterinarian. In organizational terms, most producers are not linked to any organization, mainly because of mistrust. Producers identify their animals as the most important positive aspect of their productive system, whereas infrastructure was the most substantial negative aspect of it. Most of the producers consider that their productive system is relevant for the area where they belong, which they believe turn into a high local demand. The results of this work are limited to establish an integral characterization of the study population, yet they provide general features based on the experience of small producers, which may be useful for further studies....
Una revisión de la investigación sobre justicia ambiental urbana en Latinoamérica
(Universidade do Estado Rio de Janeiro, 2017)
El objetivo de la presente revisión es identificar las tendencias en la investigación sobre justicia ambiental urbana en Latinoamérica. Se consultaron las bases de datos de Scopus, Redalyc, Google Académico y Scielo y se seleccionaron los artículos...
The main objective to this review is to identify trends in research on urban environmental justice in Latin America. Scopus, Redalyc, Google Academic and Scielo databases were consulted and the articles that met the designed search criteria were selected. A bibliometric description of the scientific production about urban environmental justice in Latin America is presented and the main conceptual and methodological approaches are identified, along with* the type of sources used and the main conclusions reached in each study. The results indicate that the investigations have focused on Mexican and Chilean cities. Additionally, they are also recent, scarce and concentrated in classical aspects of social distribution of environmental damages such as natural hazards and pollution; and environmental goods, such as green spaces and public services....
The main objective to this review is to identify trends in research on urban environmental justice in Latin America. Scopus, Redalyc, Google Academic and Scielo databases were consulted and the articles that met the designed search criteria were selected. A bibliometric description of the scientific production about urban environmental justice in Latin America is presented and the main conceptual and methodological approaches are identified, along with* the type of sources used and the main conclusions reached in each study. The results indicate that the investigations have focused on Mexican and Chilean cities. Additionally, they are also recent, scarce and concentrated in classical aspects of social distribution of environmental damages such as natural hazards and pollution; and environmental goods, such as green spaces and public services....