951 resultados para Uses and Gratifications


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Alho do mato (Cipura paludosa, Iridaceae) is a medicinal plant found in the Amazon rain forest, North of Brazil. It has been used to treat algic, inflammatory and infectious processes. The aim of this study was to evaluate the anti-inflammatory and antinociceptive action of the crude Cipura paludosa ethanolic extract at concentrations ranging between 2.0 and 4.0% in Oil and Water cream formulations for topical use. The physical-chemical stability of the formulations was monitored over a six-month period with the use of accelerated stability tests. In order to evaluate the anti-inflammatory and antinociceptive activities, we used a paw edema test induced by carrageenan and a formalin test, respectively. The paw edema test showed that there was a statistical difference in the control group in relation to the treatments. The formalin test did not confirm antinociceptive action of the treatments with the extract in the early phase of the test. However, statistical difference was confirmed for the treatments in relation to the control in the late phase. The antinociceptive and anti-inflammatory activities of Cipura paludosa preparations, as demonstrated in the results, at least partially support the ethno-medical uses of this plant.

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Dissertação de mestrado integrado em Engenharia Biomédica (área de especialização em Informática Médica)

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Chlorine oxyanions are valuable electron acceptors for microorganisms. Recent findings have shed light on the natural formation of chlorine oxyanions in the environment. These suggest a permanent introduction of respective compounds on Earth, long before their anthropogenic manufacture. Microorganisms that are able to grow by the reduction of chlorate and perchlorate are affiliated with phylogenetically diverse lineages, spanning from the Proteobacteria to the Firmicutes and archaeal microorganisms. Microbial reduction of chlorine oxyanions can be found in diverse environments and different environmental conditions (temperature, salinities, pH). It commonly involves the enzymes perchlorate reductase (Pcr) or chlorate reductase (Clr) and chlorite dismutase (Cld). Horizontal gene transfer seems to play an important role for the acquisition of functional genes. Novel and efficient Clds were isolated from microorganisms incapable of growing on chlorine oxyanions. Archaea seem to use a periplasmic Nar-type reductase (pNar) for perchlorate reduction and lack a functional Cld. Chlorite is possibly eliminated by alternative (abiotic) reactions. This was already demonstrated for Archaeoglobus fulgidus, which uses reduced sulfur compounds to detoxify chlorite. A broad biochemical diversity of the trait, its environmental dispersal, and the occurrence of relevant enzymes in diverse lineages may indicate early adaptations of life toward chlorine oxyanions on Earth.

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This paper reports on a new façade system that uses passive solutions in the search for energy efficiency. The differentials are the versatility and flexibility of the modules, which are important advantages of the system. The thermal performance of Trombe walls and glazings and the daylighting performance of glazing were the key aspects analyzed in the results. Computational simulations were accomplished for the thermal performance of different arrangements of the modules with DesignBuilder software. The glazing daylighting performance was studied by means of Ecotect and Desktop Radiance programs and compared with the transmittance curves of glazings. Occupancy profile and internal gains were fixed according to the Portuguese reality for both studies. The main characteristics considered in this research were the use of two double glazings, four different climates in Portugal and one and two Trombe walls in the façade. The results show an important reduction in the energy consumption with the use of Trombe walls and double self-cleaning glazing in the façade, which also presented better daylighting performance.

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Dissertação de mestrado em Bioengenharia

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This research uses the textile/text axis concept as a conceptual tool to investigate the role of textile and text in contemporary women’s art practice and theorizing, investigating textile as a largely hitherto unacknowledged element in women’s art practice of the late 20th and early 21st centuries. Textile and text share a common etymological root, from the Latin textere to weave, textus a fabric. The thesis illuminates the pathways whereby textile and text played an important role in women reclaiming a speaking voice as creators of culture and signification during a revolutionary period of renewal in women’s cultural contribution and positioning. The methodological approach used in the research consisted of a comprehensive literature review, the compilation of an inventory of relevant women artists, developing a classificatory system differentiating types of approaches, concerns and concepts underpinning women’s art practice vis a vis the textile/text axis and a series of three in-depth case studies of artists Tracey Emin, Louise Bourgeois and Faith Ringgold. The thesis points to the fact that contemporary women artists and theorists have rounded their art practice and aesthetic discourse in textile as prime visual metaphor and signifier, turning towards the ancient language of textile not merely to reclaim a speaking voice but to occupy a ground breaking locus of signification and representation in contemporary culture. The textile/text axis facilitated women artists in powerfully countering a culturally inscribed status of Lacanian ‘no-woman’ (a position of abjection, absence and lack in the phallocentric symbolic). Turning towards a language of aeons, textile as fertile wellspring, the thesis identifies the methodologies and strategies whereby women artists have inserted their webs of subjectivities and deepest concerns into the records and discourses of contemporary culture. Presenting an anatomy of the textile/text axis, the thesis identifies nine component elements manifesting in contemporary women’s aesthetic practice and discourse. In this cultural renaissance, the textile/text axis, the thesis suggests, served as a complex lexicon, a system of labyrinthine references and signification, a site of layered meanings and ambiguities, a body proxy and a corporeal cartography, facilitating a revolution in women’s aesthetic praxis.

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The main objective of this thesis on flooding was to produce a detailed report on flooding with specific reference to the Clare River catchment. Past flooding in the Clare River catchment was assessed with specific reference to the November 2009 flood event. A Geographic Information System was used to produce a graphical representation of the spatial distribution of the November 2009 flood. Flood risk is prominent within the Clare River catchment especially in the region of Claregalway. The recent flooding events of November 2009 produced significant fluvial flooding from the Clare River. This resulted in considerable flood damage to property. There were also hidden costs such as the economic impact of the closing of the N17 until floodwater subsided. Land use and channel conditions are traditional factors that have long been recognised for their effect on flooding processes. These factors were examined in the context of the Clare River catchment to determine if they had any significant effect on flood flows. Climate change has become recognised as a factor that may produce more significant and frequent flood events in the future. Many experts feel that climate change will result in an increase in the intensity and duration of rainfall in western Ireland. This would have significant implications for the Clare River catchment, which is already vulnerable to flooding. Flood estimation techniques are a key aspect in understanding and preparing for flood events. This study uses methods based on the statistical analysis of recorded data and methods based on a design rainstorm and rainfall-runoff model to estimate flood flows. These provide a mathematical basis to evaluate the impacts of various factors on flooding and also to generate practical design floods, which can be used in the design of flood relief measures. The final element of the thesis includes the author’s recommendations on how flood risk management techniques can reduce existing flood risk in the Clare River catchment. Future implications to flood risk due to factors such as climate change and poor planning practices are also considered.

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Stand alone solar powered refrigeration and water desalination, two of the most popular and sought after applications of solar energy systems, have been selected as the topic of research for the works presented in this thesis. The water desalination system based on evaporation and condensation was found to be the most suitable one to be powered by solar energy. It has been established that highoutput fast-response solar heat collectors used to achieve high rates of evaporation and reliable solar powered cooling system for faster rates of condensation are the most important factors in achieving increased outputs in solar powered desalination systems. Comprehensive reviews of Solar powered cooling/refrigeration and also water desalination techniques have been presented. In view of the fact that the Institute of Technology, Sligo has a well-established long history of research and development in the production of state of the art high-efficiency fast-response evacuated solar heat collectors it was decided to use this know how in the work described in this thesis. For this reason achieving high rates of evaporation was not a problem. It was, therefore, the question of the solar powered refrigeration that was envisaged to be used in the solar powered desalination tofacilitate rapid condensation of the evaporated water that had to be addressed first. The principles of various solar powered refrigeration techniques have also been reviewed. The first step in work on solar powered refrigeration was to successfully modify a conventional refrigerator working on Platen-Munters design to be powered by highoutput fast-response evacuated solar heat collectors. In this work, which was the first ever successful attempt in the field, temperatures as low as —19°C were achieved in the icebox. A new approach in the use of photovoltaic technology to power a conventional domestic refrigerator was also attempted. This was done by modifying a conventional domestic refrigerator to be powered by photovoltaic panels in the most efficient way. In the system developed and successfully tested in this approach, the power demand has been reduced phenomenally and it is possible to achieve 48 hours of cooling power with exposure to just 7 hours of sunshine. The successful development of the first ever multi-cycle intermittent solar powered icemaker is without doubt the most exciting breakthrough in the work described in this thesis. Output of 74.3kg of ice per module with total exposure area of 2.88 m2, or 25.73kg per m2, per day is a major improvement in comparison to about 5-6kg of ice per m2 per day reported for all the single cycle intermittent systems. This system has then become the basis for the development of a new solar powered refrigeration system with even higher output, named the “composite” system described in this thesis. Another major breakthrough associated with the works described in this thesis is the successful development and testing of the high-output water desalination system. This system that uses a combination of the high-output fast-response evacuated solar heat collectors and the multi-cycle icemaker. The system is capable of producing a maximum of 141 litres of distilled water per day per module which has an exposure area of 3.24m2, or a production rate of 43.5 litres per m2 per day. Once again when this result is compared to the reported daily output of 5 litres of desalinated water per m per day the significance of this piece of work becomes apparent. In the presentation of many of the components and systems described in this thesis CAD parametric solid modelling has been used instead of photographs to illustrate them more clearly. The multi-cycle icemaker and the high-output desalination systems are the subject of two patent applications.

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Tese de mestrado em Biologia Humana e Ambiente, apresentada à Universidade de Lisboa, através da Faculdade de Ciências, 2015

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The environmental input-output approach reveals the channels through which the environmental burdens of production activities are transmitted throughout the economy. This paper uses the input-output framework and analyses the changes in Spanish emission multipliers during the period 1995-2000. By decomposing the global changes in multipliers into different components, it is possible to evaluate separately the economic and ecological impacts captured by the environmental input-output model. Specifically, in this study we distinguish between the effects on multipliers caused by changes in emission coefficients (the ecological impacts) and the effects on multipliers caused by changes in technical coefficients (the economic impacts). Our results show a significant improvement in the ecological impacts of production activities, which contributed negatively to changes in emission multipliers. They also show a deterioration in the economic impacts, which contributed positively to changes in emission multipliers. Together, these two effects lead to a small reduction in global multipliers during the period of analysis. Our results also show significant differences in the individual behaviour of different sectors in terms of their contribution to multiplier changes. Since there are considerable differences in the way individual sectors affect the changes in emission levels, and in the intensity of these effects, this means that the final effects will basically depend on the activity considered. Keywords: emission multipliers, multipliers' changes, ecological impacts, economic impacts.

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This note describes ParallelKnoppix, a bootable CD that allows econometricians with average knowledge of computers to create and begin using a high performance computing cluster for parallel computing in very little time. The computers used may be heterogeneous machines, and clusters of up to 200 nodes are supported. When the cluster is shut down, all machines are in their original state, so their temporary use in the cluster does not interfere with their normal uses. An example shows how a Monte Carlo study of a bootstrap test procedure may be done in parallel. Using a cluster of 20 nodes, the example runs approximately 20 times faster than it does on a single computer.

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The Bank of Spain uses a unique auction format to sell government bonds, which can be seen as a hybrid of a uniform and a discriminatory auction. For winning bids above the average winning bid, buyers are charged the average winning bid, otherwise they pay their respective bids. We report on an experiment that compares this auction format to the discriminatory format, used in most other countries, and to the uniform format. Our design is based on a common value model with multi-unit supply and two-unit demand. The results show significantly higher revenue with the Spanish and the uniform formats than with the discriminatory one, while volatility of prices over time is significantly lower in the discriminatory format than in the Spanish and uniform cases. Actual price dispersion is significantly larger in the discriminatory than in the Spanish. Our data also exhibit the use of bid-spreading strategies in all three designs.

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The decisions of many individuals and social groups, taking according to well-defined objectives, are causing serious social and environmental problems, in spite of following the dictates of economic rationality. There are many examples of serious problems for which there are not yet appropriate solutions, such as management of scarce natural resources including aquifer water or the distribution of space among incompatible uses. In order to solve these problems, the paper first characterizes the resources and goods involved from an economic perspective. Then, for each case, the paper notes that there is a serious divergence between individual and collective interests and, where possible, it designs the procedure for solving the conflict of interests. With this procedure, the real opportunities for the application of economic theory are shown, and especially the theory on collective goods and externalities. The limitations of conventional economic analysis are shown and the opportunity to correct the shortfalls is examined. Many environmental problems, such as climate change, have an impact on different generations that do not participate in present decisions. The paper shows that for these cases, the solutions suggested by economic theory are not valid. Furthermore, conventional methods of economic valuation (which usually help decision-makers) are unable to account for the existence of different generations and tend to obviate long-term impacts. The paper analyzes how economic valuation methods could account for the costs and benefits enjoyed by present and future generations. The paper studies an appropriate consideration of preferences for future consumption and the incorporation of sustainability as a requirement in social decisions, which implies not only more efficiency but also a fairer distribution between generations than the one implied by conventional economic analysis.

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Ecological economics has five good reasons to consider that economic globalisation, spurred by commercial and financial fluxes, to be one of the main driving forces responsible for causing environmental degradation to our planet. The first, is the energy consumption and the socio-environmental impacts which long-distance haulage entails. The second, is the ever-increasing flow of goods to far-away destinations which renders their recycling practically impossible. This is particularly significant, because it prevents the metabolic lock of the nutrients present in food and other agrarian products from taking place. The third, is that the high degree of specialization attained in agriculture, forestry, cattle, mining and industry in each region, generates deleterious effects not only on the eco-landscape structure of the uses of the soil, but on the capability to provide habitat and environmental functions to maintain biodiversity as well

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This paper presents an outline of rationale and theory of the MuSIASEM scheme (Multi-Scale Integrated Analysis of Societal and Ecosystem Metabolism). First, three points of the rationale behind our MuSIASEM scheme are discussed: (i) endosomatic and exosomatic metabolism in relation to Georgescu-Roegen’s flow-fund scheme; (2) the bioeconomic analogy of hypercycle and dissipative parts in ecosystems; (3) the dramatic reallocation of human time and land use patterns in various sectors of modern economy. Next, a flow-fund representation of the MUSIASEM scheme on three levels (the whole national level, the paid work sectors level, and the agricultural sector level) is illustrated to look at the structure of the human economy in relation to two primary factors: (i) human time - a fund; and (ii) exosomatic energy - a flow. The three levels representation uses extensive and intensive variables simultaneously. Key conceptual tools of the MuSIASEM scheme - mosaic effects and impredicative loop analysis - are explained using the three level flow-fund representation. Finally, we claim that the MuSIASEM scheme can be seen as a multi-purpose grammar useful to deal with sustainability issues.