1,828 research outputs found

    The role of substrate hydrogeology and surface hydrology in the construction of phreatomagmatic volcanoes on an active monogenetic field (Auckland, New Zealand) : a thesis presented in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Earth Science at Massey University, Palmerston North, New Zealand

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    Material removed for copyright reasons (appendices B, D and E): Agustín-Flores, J., Németh K., Cronin, S., Lindsay, J., Kereszturi, G., Brand, B., & Smith, I.E.M. (2014). Phreatomagmatic eruptions through unconsolidated coastal plain sequences, Maungataketake, Auckland Volcanic Field (New Zealand). Journalof Volcanology and Geothermal Research, 180, 203-224. doi.org/10.1016/j.jvolgeores.2014.02.021 Agustín-Flores, J., Németh, K., Cronin, S., Lindsay, J., & Kereszturi, G. (2015). Shallow-seated explosions in the construction of the Motukorea tuff ring (Auckland, New Zealand): Evidence from lithic and sedimentary characteristics. Journal of Volcanology and Geothermal Research, 304, 272-286. doi.org/10.1016/j.jvolgeores.2015.09.013 Agustín-Flores, J., Németh, K., Cronin, S., Lindsay, J., & Kereszturi, G., 2015. Construction of the North Head (Maungauika) tuff cone: a product of Surtseyan volcanism, rare in the Auckland Volcanic Field, New Zealand. Bulletin of Volcanology, 77, 11. doi:10.1007/s00445-014-0892-9Phreatomagmatic activity is pervasive in the Auckland Volcanic Field (AVF) with more than two thirds of the erupted volcanoes showing this type of activity at different degrees, dominantly at the onset of their eruptive histories. In general, the volcanoes built in the northern AVF rest on Late Miocene Waitemata Group rocks (turbiditic siltstone and sandstone succession), whereas in the southern AVF the Waitemata rocks are overlain by tens of metres of Plio-Pleistocene, water-saturated sediments (Tauranga Group and Kaawa Formation). Identifying the control exerted by the type of substrate in the eruption dynamics of the phreatomagmatic phases of three volcanoes in the AVF is the objective of this study. The stratigraphic, sedimentary, and pyroclast characteristics of the phreatomagmatic sequences of Maungataketake, Motukorea, and North Head volcanoes, together with supplementary information on the geology and hydrogeology of the area, were investigated to solve the problem. Three phreatomagmatic eruptive scenarios were outlined. Scenario 1 (Maungataketake eruption) and Scenario 2 (Motukorea eruption) depict the formation of maar-diatreme volcanoes in the southern and northern AVF, respectively. The dominant presence of lithics from the upper part of the substrate in their tephra rings suggests the construction of their tephra rings from shallow-seated explosions. Due to the water-saturated sediments filling the diatreme in Scenario 1, the eruption appears to have remained relatively wet throughout. Conversely, the drier Waitemata rocks involved in Scenario 2 promoted a progressive drying of the eruption. Scenario 3 (North Head eruption) represents a Surtseyan eruption scenario in which the rising magma erupted to the shallow sea floor (a few metres-water depth), promoting rapid chilling and explosive fragmentation. This study shows that the characterization of lithics within the tephra ring and the geological and hydrogeological information provide valuable clues to envisage the degree of influence of the substrate in the phreatomagmatic eruption dynamics. Other studies in the AVF appear to confirm this view. It is proposed that any future phreatomagmatic eruption in the AVF will be strongly influenced by the substrate hydrogeology and geology, as well as the surface hydrological conditions

    Aspectos de la teoría gramatical de Gougenheim.

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    Agua y desarrollo urbano en la Castilla medieval: aportaciones a su estudio en la ciudad de Guadalajara

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    One of the most critical elements for urban development in medieval Castile was access to water resources that could be used to supply human settlements. Depending on the climatic conditions, the surrounding terrain and previously existing infrastructures, each city and town in the kingdom sought the best means to secure a water supply for its population. In this article, we will analyse how the council of Guadalajara, together with the main religious and civil powers in the city, began to construct the local water supply network in the Late Middle Ages, fed by springs located in a place known as El Sotillo, and the start of commercial exploitation of the Henares River nearby the city. Water, a scarce resource in the Alcarria region, was of critical importance for the economy in the Late Middle Ages, as well as being a symbol of social prestige, and aroused the interest of all members of the local society.Uno de los elementos críticos del urbanismo castellano en la Edad Media era el acceso a recursos hídricos que pudieran servir para el abastecimiento humano. En función del clima, la orografía, y las infraestructuras heredadas de épocas anteriores, cada ciudad y villa del reino trató de buscar la mejor manera de asegurar el suministro de agua para sus vecinos. A lo largo de este trabajo se analiza la forma en la que el concejo de Guadalajara, así como los principales poderes religiosos y nobiliarios de la ciudad, fueron trazando la red de abastecimiento urbano durante la Baja Edad Media, a partir de las fuentes del paraje conocido como El Sotillo, y cómo realizaron la explotación económica del cauce del río Henares en las cercanías del municipio. El agua, bien escaso en la Alcarria, fue durante los siglos bajomedievales un elemento de gran importancia económica y símbolo de prestigio social, que despertó el interés de todos los grupos de la sociedad arriacense

    Molybdenum-catalyzed enantioselective sulfoxidation controlled by a nonclassical hydrogen bond between coordinated chiral imidazolium-based dicarboxylate and peroxido ligands

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    Chiral alkyl aryl sulfoxides were obtained by molybdenum-catalyzed oxidation of alkyl aryl sulfides with hydrogen peroxide as oxidant in mild conditions with high yields and moderate enantioselectivities. The asymmetry is generated by the use of imidazolium-based dicarboxylic compounds, HLR. The in-situ-generated catalyst, a mixture of aqueous [Mo(O)(O2)2(H2O)n] with HLR as chirality inductors, in the presence of [PPh4]Br, was identified as the anionic binuclear complex [PPh4]{[Mo(O)(O2)2(H2O)]2( -LR)}, according to spectroscopic data and Density Functional Theory (DFT) calculations. A nonclassical hydrogen bond between one C–H bond of the alkyl R group of coordinated (LR)- and one oxygen atom of the peroxido ligand was identified as the interaction responsible for the asymmetry in the process. Additionally, the step that governs the enantioselectivity was theoretically analyzed by locating the transition states of the oxido-transfer to PhMeS of model complexes [Mo(O)(O2)2(H2O)( 1-O-LR)]- (R = H, iPr). The DDG6= is ca. 0 kcal mol-1 for R = H, racemic sulfoxide, meanwhile for chiral species the DDG6= of ca. 2 kcal mol-1 favors the formation of (R)-sulfoxide.Junta de Andalucía (Proyecto de Excelencia FQM-7079)Universidad de Sevilla (VI Plan Propio

    Victoria : El avance de la lógica privativa sobre los espacios públicos

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    El primer segmento de este trabajo está constituido por un breve apartado histórico de Victoria con el fin de brindar un conocimiento sobre el desarrollo histórico y urbano de dicha localidad. Explicaremos luego el impacto del modelo neoliberal en la composición socio-urbana de la localidad, centrándonos en el proceso de fragmentación de su trama urbana. En el tercer segmento prestaremos particular atención al proceso de poblamiento de la zona costera, poniendo el foco en las instituciones que fueron instalándose a la veda del río. Por último, abocaremos nuestro análisis a dos tipos particulares de aquellas instituciones: los clubes náuticos y las costaneras públicas. Habremos de poner el foco en dichas instituciones debido a que -a nuestro entender- la comparación y explicación conjunta de ambos espacios permiten develar las lógicas y perspectivas sociales que operan de fondo en la zona del río configurando su particular trama urbana.Facultad de Humanidades y Ciencias de la Educació

    Study of the preparation process and variation of wall components in chia (Salvia hispanica L.) oil microencapsulation

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    A study of the microencapsulation process of omega-3 rich oil extracted from chia (Salvia hispanica L.) seeds was carried out, which included a comparative analysis of the microcapsules obtained by the spray- and freeze-drying methods using isolated soy proteins and maltodextrin as wall materials at different proportions. Color characterization of the obtained powders was performed and revealed a darker and yellower appearance of the freeze-dried samples compared with the spray-dried ones. Moisture content was measured for each sample and all presented values around 3.5%. The SEM micrographs revealed that spray-dried microcapsules can occur individually or may form clusters or aggregates, with the particles exhibiting a size range varying from 4 to 10 µm. Encapsulation efficiency was measured, with no significant differences found between drying methods or on varying the proportion of wall components (all samples presented values of aproximately 60%). The oxidative stability of microencapsulated oils under accelerated oxidative conditions revealed protection factors 2-fold higher for all samples. In addition, microencapsulated oil stored under 25 ºC revealed lower hydroperoxide values than those of unencapsulated oil throughout the whole storage test. Finally, oil encapsulated in SPI microcapsules also showed lower HPV values than that of the acceptable limit for virgin and cold-pressed vegetable oils (15 meq. O2/kg oil) during the storage test, while unencapsulated oil attained the acceptable limit in 62 days. This result represents an increase in the time of the oil shelf life of between 30 and 48%.Fil: González, Agustín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; ArgentinaFil: Martinez, Marcela Lilian. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Paredes, Alejandro Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica; ArgentinaFil: Leon, Alberto Edel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; ArgentinaFil: Ribotta, Pablo Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; Argentin

    O Questionário de Metas de Realização 3 × 2- Argentina (3 × 2 AGQ-AR): Adaptação, Estrutura Fatorial e Consistência Interna

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    Este trabajo evaluó la adaptación, validez y confiabilidad del Cuestionario de metas de logro 3 × 2 (Elliot et al., 2011) en una muestra de estudiantes universitarios argentinos. Se realizó una traducción directa al español y se analizó su equivalencia en una muestra bilingüe. Las correlaciones entre las versiones original y traducida de las escalas fueron moderadas y altas (.53 a .93). En dos instancias, se proveyó evidencia de la estructura factorial del instrumento mediante análisis factorial confirmatorio y se examinó la consistencia interna a través de los coeficientes alfa y omega. Los índices de ajuste apoyaron el modelo propuesto de metas 3 × 2 (S-B χ 2 /df = 1.39, p < .001, CFI = .99, RMSEA [IC 95] = .04 [.02-.06]) y fueron superiores a diez modelos alternativos. La consistencia interna de cada escala fue muy buena (.80 a .96) y similar a la de la investigación original.This research examined the adaptation, validity and reliability of the 3 × 2 Achievement Goal Questionnaire (Elliot, Murayama, & Pekrun, 2011) in a sample of Argentine university students. A direct translation into Spanish was made and its equivalence was analyzed in a bilingual sample. The correlations between the original and translated versions of the scales were moderate and high (.53 to .93). In two instances, evidence of the factor structure of the instrument was provided by confirmatory factor analysis and the internal consistency was examined by the coefficients alpha and omega. The fit indexes support the proposed 3 × 2 goal model (S-B χ2/df = 1.39, p < .001, CFI = .99, RMSEA [IC 95] = .04 [.02-.06]) and were superior to ten alternative models. The internal consistency of each scale was very good (.80 to .96) and similar to that of the original research.Este trabalho avaliou a adaptação, validade e confiabilidade do questionário de metas de realização 3 × 2 (Elliot et al., 2011) em uma amostra de estudantes universitários argentinos. Foi realizada tradução direta para o espanhol e sua equivalência analisada em uma amostra bilíngue. As correlações entre as versões original e traduzida das escalas foram moderadas e altas (.53 a .93). Em dois casos, a evidência da estrutura fatorial do instrumento foi fornecida por análise fatorial confirmatória e a consistência interna foi examinada por meio dos coeficientes alfa e ômega. Os índices de ajuste apoiaram o modelo de metas 3 × 2 proposto (S-B χ 2 /df = 1.39, p < .001, CFI = .99, RMSEA [IC 95] = .04 [.02-.06]) e foram superiores a dez modelos alternativos. A consistência interna de cada escala foi muito boa (.80 a .96) e semelhante à da pesquisa original.Fil: Sánchez Rosas, Javier. Universidad Nacional de Córdoba; ArgentinaFil: Alonso Crespo, Agustín. Universidad Nacional de Córdoba; ArgentinaFil: Furlan, Luis Alberto. Universidad Nacional de Córdoba; ArgentinaFil: Freiberg Hoffmann, Agustín. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires; Argentin

    Alcances y limitaciones de la aplicación del enfoque agroecológico a sistemas productivos extensivos del centrosur de la provincia de Buenos Aires

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    El enfoque actual para manejar y diseñar los agroecosistemas ha ocasionado problemáticas en las dimensiones económica, social, ecológica. Para lograr un cambio hacia alternativas más sustentables aparece el enfoque agroecológico, siendo un nuevo paradigma para fortalecer los procesos naturales, con una visión holística y sistémica, que perdure en el largo plazo. Se analizaron las potencialidades y limitaciones que tiene el enfoque agroecológico para implementarse en el centro-sur de la provincia de Buenos Aires, mediante entrevistas a diferentes actores del sector productivo. Las principales potencialidades que se obtuvieron son la visualización de la estabilidad y sustentabilidad de los sistemas mixtos, y la búsqueda de alternativas sustentables por parte de diferentes actores. Las mayores limitaciones fueron la falta de profesionales para un manejo agroecológico, y la no visualización de la Agroecología como alternativa.The current approach to managing and designing agro-ecosystems has caused problems in the economic, social, environmental dimensions. To achieve a shift towards more sustainable alternatives agroecological approach appears to be a new paradigm to strengthen natural processes, with a holistic and systemic that lasts over the long term. The potentialities and limitations of the agro-ecological approach to be implemented in the southcentral province of Buenos Aires, through interviews with various actors in the productive sector were analyzed. The main potentials that were obtained are viewing the stability and sustainability of mixed systems, and finding sustainable alternatives by different actors. The major constraints were lack of professional for agro-ecological management, and nondisplay of agroecology as an alternative

    Examining the role of product involvement in consumption elicited emotions

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    La implicación tiene una influencia muy importante en el comportamiento del consumidor. Este trabajo aborda las siguientes preguntas: “¿Influye la implicación con el producto en cómo las emociones crean la satisfacción con los productos?”, y “¿la implicación con el producto desempeña un papel moderador en las relaciones emociones-satisfacción?”. Basándonos en la Teoría de la Asimetría Hedónica, mediante un Modelo de Ecuaciones Estructurales (SEM) analizamos la influencia de las emociones en la satisfacción. Se recogió una muestra de 570 consumidores de un producto de alta implicación –vino-, y una muestra de 431 consumidores para el producto de baja implicación –una taza de café-. Los resultados muestran que las emociones positivas ejercen una influencia mayor en la satisfacción de los consumidores para el producto de baja implicación que para el producto de alta implicación, sugiriendo los factores situacionales –como la ocasión de consumo- podrían estar actuando como potenciadores de las emociones positivas. Adicionalmente, se ofrece evidencia empírica del rol moderador de la implicación en la relación que existe entre las emociones derivadas del consumo y la satisfacción del consumidor.Involvement has a major impact on consumer behavior. This study addresses the following questions: “Does product involvement influence how emotions drive satisfaction with products?”, and “does product involvement play a moderating role in the relationship emotions-satisfaction?”. Based on the Theory of the Hedonic Asymmetry we test through Structural Equation Modeling (SEM) how emotions drive consumer satisfaction. A sample of 570 respondents was gathered for a high involvement product –wine-, while a sample of 431 consumers was collected for a low involvement product –a cup of coffee-. Findings show that positive emotions exert a higher influence on satisfaction in low involvement products, compared to high involvement products, suggesting that situational factors, such as the occasion of consumption, could be acting as qualifiers of positive emotions. Additionally, we provide empirical support for the moderating role of product involvement as influencing the relationship between consumption elicited emotions and consumer satisfaction
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