35,173 research outputs found

    Inventario ambiental de los elementos flora, fauna y agua que permita establecer el grado de conservación y los servicios ecosistémicos ofrecidos por la Reserva los Robles del Municipio de Palestina – Huila.

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    En Colombia las reservas naturales, se han visto afectadas por la pérdida de biodiversidad debido a problemáticas ambientales asociadas a actividades antrópicas, alterando considerablemente los bosques naturales, generando fragmentación de cobertura vegetal disminuyendo así la conectividad de especies y exponiéndolas a extinguirse; esta fragmentación causa degradación en la calidad de los ecosistemas, lo cual disminuye la provisión de servicios ecosistémicos que oferta en beneficio de la población. La reserva natural los Robles representa un alto potencial en recursos naturales la cual posee gran variedad en especies de flora, fauna, cuerpos de agua, proporcionando servicios ambientales que representan una gran importancia para la zona. Realizar una investigación por medio de un inventario ambiental permitirá el reconocimiento del estado actual de la reserva natural Los Robles, la identificación de nuevas especies, la caracterización de cada uno de los componentes naturales, los servicios ecosistémicos que oferta, entre otros. Se identificará cada una de las problemáticas que puedan afectar la reserva. De esta manera se propondrán medidas que garanticen a futuro la sostenibilidad de la biodiversidad, y a su vez aportar al cuidado de los recursos naturales, mejorar la calidad de vida de las comunidades y reconocer el valor que proporciona a nivel ambiental.In Colombia, natural reserves have been affected by the loss of biodiversity due to environmental problems associated with anthropic activities, considerably altering natural forests, generating fragmentation of plant cover, thus reducing the connectivity of species, and exposing them to extinction; This fragmentation causes degradation in the quality of ecosystems, which reduces the provision of ecosystem services that it offers for the benefit of the population. The Los Robles natural reserve represents a high potential in natural resources which has a great variety in species of flora, fauna, bodies of water, providing environmental services that represent great importance for the area. Carrying out an investigation through an environmental inventory will allow the recognition of the current state of the Los Robles natural reserve, the identification of new species, the characterization of each of the natural components, the ecosystem services it offers, among others. Each of the problems that may affect the reservation will be identified. In this way, measures will be proposed that guarantee the future sustainability of biodiversity, and in turn contribute to the care of natural resources, improve the quality of life of communities and recognize the value it provides at an environmental level

    The Reputations of Sir Francis Burdett

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    Optimising acoustic cavitation for industrial application

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    The ultrasonic horn is one of the most commonly used acoustic devices in laboratories and industry. For its efficient application to cavitation mediated process, the cavitation generated at its tip as a function of its tip-vibration amplitudes still needed to be studied in detail. High-speed imaging and acoustic detection are used to investigate the cavitation generated at the tip of an ultrasonic horn, operating at a fundamental frequency, f0, of 20 kHz. Tip-vibration amplitudes are sampled at fine increments across the range of input powers available. The primary bubble cluster under the tip is found to undergo subharmonic periodic collapse, with concurrent shock wave emission, at frequencies of f0/m, with m increasing through integer values with increasing tip-vibration amplitude. The contribution of periodic shock waves to the noise spectra of the acoustic emissions is confirmed. Transitional input powers for which the value of m is indistinct, and shock wave emission irregular and inconsistent, are identified through Vrms of the acoustic detector output. For cavitation applications mediated by bubble collapse, sonications at transitional powers may lead to inefficient processing. The ultrasonic horn is also deployed to investigate the role of shock waves in the fragmentation of intermetallic crystals, nominally for ultrasonic treatment of Aluminium melt, and in a novel two-horn configuration for potential cavitation enhancement effects. An experiment investigating nitrogen fixation via cavitation generated by focused ultrasound exposures is also described. Vrms from the acoustic detector is again used to quantify the acoustic emissions for comparison to the sonochemical nitrite yield and for optimisation of sonication protocols at constant input energy. The findings revealed that the acoustic cavitation could be enhanced at constant input energy through optimisation of the pulse duration and pulse interval. Anomalous results may be due to inadequate assessment for the nitrate generated. The studies presented in this thesis have illustrated means of improving the cavitation efficiency of the used acoustic devices, which may be important to some selected industrial processes

    Representaciones sociales de salud. Enfermedad en en profesionales de la salud y sus usuarios indígenas zapotecas de Oaxaca

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    Tesis de DoctoradoLas preguntas centrales que guían el presente trabajo giran en torno a saber ¿Cuáles son las representaciones sociales, en relación con los conceptos de salud/enfermedad, que construyen tanto los profesionales de salud como los usuarios del servicio médico público de la comunidad ndígena de San Bartolomé Quialana, Oaxaca? y a partir de ello, conocer ¿Cómo dichas representaciones presentan divergencias y convergencias culturales que distancian y/o acercan el diálogo intercultural en la atención de la salud? De ahí que el objetivo general consiste en analizar las representaciones sociales sobre salud/enfermedad de los prestadores de servicios de salud y de los usuarios de la comunidad indígena de San Bartolomé Quialana, Oaxaca para identificar las divergencias y convergencias que propicien el dialogo intercultural entre dichos actores, a través de los discursos y vivencia de los propios sujetos y de la observación de sus prácticas en salud. Dentro de algunos resultados a los que se llega se encuentra El estudio de las representaciones sociales entre profesionales de la salud y usuarios de Quialana, Oaxaca, permite desengranar cada uno de los denominados “conflictos culturales” que se manifiestan en la interpretación y matrices de conocer, sentir y expresar la salud y la enfermedad en cada uno de ellos. En este sentido, interpretar y comprender las representaciones sociales que se configuran en las dimensiones y dinámicas de dicho conocimiento de sentido común, permite crear vínculos de interacción e interculturalidad que promueven una salud justa, solidaria y ética para todos los pobladores, incluyendo en esta estructura de la población a los profesionales de la salud. Desde esta perspectiva se puede señalar que, lo que encierra al término de conflicto y/o arraigo cultural, no es más que aquello que no se puede explicar en términos de producción y evidencia científica, pero que se ancla a los conceptos subjetivos y culturales de la salud y la enfermedad, tal es el caso de las desigualdades sociales, el cual no se percibe solamente desde el espacio territorial de pobreza y geodistribución económica mundial y nacional, sino que el término de desigualdad abarca un sin número de significados que se produjeron a partir de los procesos coloniales, capitalistas, patriarcales y hegemónicos del modelo biomédico en la interpretación epistemológica e interacción ontológica y social con las otredades. En esta dirección, la salud como término biomédico es manifestado por los profesionales como una utopía que solo puede ser abordado desde lo institucional e individual para que este pueda ser posible, medible, transferible y controlable, en cambio, los usuarios más que hablar de salud, prefieren posicionarse desde la connotación de la sanación y el equilibrio para configurar su corporalidad como un ente que interactúa constanmente con el universo y los seres que lo habitan, por tanto, las corporalidades presentan desequilibrios que requieren de enseñanzas, procesos, estrategias y modos de vida individual y colectiva que habrán de repensarse y reflexionarse en conjunto para encontrar la sanación y equilibrio. No obstante, para ambos, actores y actoras, la salud no puede ser pensada sólo en términos de ausencia de enfermedad o de completo estado de bienestar físico y psicológico. Así, recuperar las memorias de los profesionales y usuarios permite reconocer que la salud vista desde el esquema de configuración de las representaciones sociales se descapitaliza del sentido literal y simbólico que se transmite desde las instituciones de la salud.Universidad Autónoma del Estado de México, Conacy

    Pontus in Antiquity: aspects of identity

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    The purpose of this thesis is the presentation of the interaction between the successive inhabitants of Pontus in antiquity, indigenous Anatolians, Greeks, Persians and Romans. Limited archaeological evidence cannot determine the precise extent of interaction, although the available information substantiates the notion of a slow, but steady amalgamation. Initially, the intermingling was based on mutual trading links. Although the Hellenic cultural element tended to surface, Eastern factors remained visible. The Mithridatic dynasty was established around the vicinity of Pontus, creating the 'Kingdom of Pontus' which reached its height under Mithridates VI. His administrative and military policy appears to have placed the foundations for the later, Roman corresponding structures. His policies-propaganda reflected the GraecoEastern image of a king, which appealed to the Greek and Persian-Eastern inhabitants of his kingdom, Asia Minor and, to a lesser extent, mainland Greece. This GraecoEastern image might have nourished the concept of a shared history among the inhabitants of Pontus. Their interactions appear to have given rise to an unnamed, local culture, which was enriched with the relevant Roman practices. Around the third century A.D., the Roman administrative patterns might have established an externally defined appellation. During Roman times, Christianity started to be established in Pontus. Although it was not yet a socio-political factor, its non-racial nature prevailed in later centuries. The influence of the Roman-Christian elements can still be observed in the modern Ponti an identity. In antiquity, (lack of) evidence indicates that no group defined themselves as 'Pontics' or 'Pontians' and an internally defined Pontic identity is unlikely to have existed. However, people associated themselves with the geographical area of Pont us, cultural and religious concepts were frequently amalgamated, while the notion of a common descent and a shared history might have been unconsciously fostered. These factors can assist in the understanding of the 'Pontians' today

    The Caribbean Syzygy: a study of the novels of Edgar Mittelholzer and Wilson Harris

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    The problem of racial inheritance - the "search for identity" - is a recurring theme in the criticism of Caribbean literature. It is a pre-occupation with Caribbean writers, affecting both subject matter and literary quality, as FM. Birbalsingh, for example, has shown with reference to the novels of John Hearne and E,R. Braithwaite (Caribbean quarterly Vols. 14, December 1968 and 16, March 1970). This study of the work of Edgar Mittelholzer and Wilson Harris will attempt to show that there are important areas still to be explored relating Caribbean literature to its complex racial and cultural background. Both Mittelholzer and Harris deserve close, critical study in their own right; but a parallel examination reveals similarities and differences which bring into sharper focus wider concerns of Caribbean literature. The two important directions of West Indian writing are more clearly seen: the one, pioneered by Mittelholzer, in which the writer looks outward towards a "parent" culture, and the other looking inward, seeking in its own, complex inheritance the raw material for new and original growth. Mittelholzer and Harris are both Guyanese of mixed racial stock, both deeply concerned with the psychological effects of this mixture, and both writers have a profound awareness of the Guyanese historical and cultural heritage. They also share a deep feeling for the Guyenese landscape which appears in their work as a brooding presence affecting radically -the lives of those who live within i-t. Mittelholzer's attitude to his mixed racial and cultural origins, however, produces in his work a schizophrenic Imbalance while Harris, by accepting racial and cultural complexity as a starting-point, initiates a uniquely creative and experimental art. Mittelholzer, in his approach to history, human character eM landscape, remains a vi "coastal" writer never really concerned (as Harris is) with. the deeper significance of the "Interior" and all that this implies, both in a geographical and psychological sense. The fact that Mittelbolzer's work reflects a psychological imbalance induced by a pre-occupation with racial identity has been demonstrated by Denis Williams in the 1968 Mittelholzer Lectures, and by Joyce Sparer in a series of articles in the Guyana Graphic. Mittelholzer's awareness of this imbalance, however, and his attempt to come to terms with it in his art remain to be examined and documented, as does Harris's attempt to create am "associative" art aimed at healing the breach in the individual consciousness of Caribbean Man. The aim of this study is to demonstrate that Mitteholzer and. Harris, although antithetical in impact and style (each representing an approach to fiction directly opposed to the other) are, in fact, the opposite elements of a dichotomy. Their work illustrates the negative and positive aspects of the racial and cultural schizophrenia of the Caribbean, for both writers in their different ways are preoccupied with (and therefore have embodied in their work) the juxtaposition and, contrasting of apparently irreconcilable emotional and intellectual qualities - the Caribbean Syzygy

    The withdrawal of being and the discursive creation of the modern subject - an examination of the movement form being to non-being through a consideration of Heideggerean and Arsitotelian notions of being

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    This work considers what it means to 'be' human and seeks to show that it is in the activity of 'being' human that our individual identity lies, because this is the activity that determines what we are and what we will become. Aristotle asked the fundamental metaphysical question, "is a human being idle by nature?" and concluded, from his realisations concerning the dynamic nature of reality, that he is not. Accordingly, the metaphysical vision of 'beinghuman' that Aristotle articulated, which is considered and applied in this work, in contrast to the static notions of being presented by Heidegger and Christian scholasticism, presents an understanding of man as a potentially dynamic and internally active being, capable of maintaining himself by bein~ attuned to reality and thereby contemplating God. It seems most timely to explore Aristotle's understanding of 'being-human' because much postmodern thought seems to be concerned with locating the 'self, or explicating its disappearance in terms of an emancipation from form, or as the exposure of some form of illusion that has kept us all living the lie of selfhood. However, the 'absent' postmodern self finds a place in Aristotle's metaphysical vision, because not only did Aristotle recognise the significance of actively 'being' human, he also recognised that through deprivation and incapacity some forms of being can go out of existence or become something else. And it appears that our postmodern form of unconscious existence constitutes such an altered form, determined according to a deprivation of actively 'being', i.e., by 'non-being.' The determining movement of 'non-being', which emerges from the ontological gap created by failing to 'be', is considered throughout this work, particularly with regard to developments in language and technology, because it is through our single-minded engagement in external productive activities, which are incidental to 'being-human', that we have avoided the inner contemplative activity that inheres in human 'thinghood'

    Alternativas de asociatividad territorial para la subregión del Oriente Antioqueño : análisis de viabilidad frente a la implementación de nuevos esquemas de integración en el Valle de San Nicolás

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    El presente trabajo, se centra en analizar cuáles han sido las claves de la asociatividad territorial entre los municipios de la subregión del Oriente Antioqueño, en especial los ubicados en la zona del Altiplano, o también llamado Valle de San Nicolás, a saber: Rionegro, La Ceja del Tambo, El Retiro, La Unión, El Carmen de Viboral, Guarne, San Vicente Ferrer, Marinilla y El Santuario. Dentro de dichas claves, se intentarán comprender los aciertos y desaciertos de estas dinámicas de integración, haciendo un análisis de las características de los esquemas que hoy están conformados y en los que se encuentran asociados éstos municipios. Se proponen tres alternativas nuevas de integración que pueden ser exploradas en la subregión; por un lado, un esquema que ya ha sido debatido sin llegar a concretarse, como lo es la iniciativa de crear un Área Metropolitana en el Oriente; y de otro lado, se propone la exploración de figuras que aún no han sido discutidas dentro de este escenario, como la posibilidad de conformar una Región de Planeación y Gestión (RPG), o la de crear una figura de régimen especial que se asemeje a la recién creada Región Metropolitana de Bogotá. Sobre cada una, se realizará un análisis de viabilidad tanto desde el punto de vista legal -a la luz de las disposiciones contenidas en el ordenamiento jurídico colombiano- como desde el punto de vista político, toda vez que la conformación de un Esquema Asociativo Territorial depende en gran medida de la voluntad de los tomadores de decisiones.The present paper focuses on analyzing the keys to territorial associativity among the municipalities of the Eastern Antioquia subregion, especially those located in the Altiplano area, or also called the San Nicolás Valley, namely: Rionegro, La Ceja del Tambo, El Retiro, La Unión, El Carmen de Viboral, Guarne, San Vicente Ferrer, Marinilla and El Santuario. Within these keys, an attempt will be made to understand the successes and failures of these integration dynamics, making an analysis of the characteristics of the schemes that today are formed and in which these municipalities are associated. Three new integration alternatives are proposed to can be explored in the subregion; one of them, a scheme that has already been debated without materializing, such as the initiative to create a Metropolitan Area in the Eastern subregion; in addition, this paper proposes the exploration of figures that have not yet been discussed within this scenario, such as the possibility of creating a Planning and Management Region (RPG for its acronym in Spanish), or creating a special regime figure that resembles the newly created Metropolitan Region of Bogotá. On each one, a feasibility analysis will be carried out both from the legal point of view -according with the content of the Colombian legal system- and from the political point of view, since the formation of a Territorial Associative Scheme depends largely of the will of the decision makers

    The influence of a Hamiltonian vibration vs a bath vibration on the 2D electronic spectra of a homodimer

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    We elucidate the influence of the system–bath boundary placement within an open quantum system, with emphasis on the two-dimensional electronic spectra, through the application of the hierarchical equations of motion formalism for an exciton system. We apply two different models, the Hamiltonian vibration model (HVM) and bath vibration model (BVM), to a monomer and a homodimer. In the HVM, we specifically include the vibronic states in the Hamiltonian capturing vibronic quenching, whereas in the BVM, all vibrational details are contained within the bath and described by an underdamped spectral density. The resultant spectra are analyzed in terms of energetic peak position and thermodynamic broadening precision in order to evaluate the efficacy of the two models. The HVM produces 2D spectra with accurate peak positional information, while the BVM is well suited to modeling dynamic peak broadening. For the monomer, both models produce equivalent spectra in the limit where additional damping associated with the underdamped vibration in the BVM approaches zero. This is supported by analytical results. However, for the homodimer, the BVM spectra are redshifted with respect to the HVM due to an absence of vibronic quenching in the BVM. The computational efficiency of the two models is also discussed in order to inform us of the most appropriate use of each method
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