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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

On the primarity of some block intersection graphs

Vodah, Sunday January 2018 (has links)
Philosophiae Doctor - PhD / A tactical con guration consists of a nite set V of points, a nite set B of blocks and an incidence relation between them, so that all blocks are incident with the same number k points, and all points are incident with the same number r of blocks (See [14] for example ). If v := jV j and b := jBj; then v; k; b; r are known as the parameters of the con guration. Counting incident point-block pairs, one sees that vr = bk: In this thesis, we generalize tactical con gurations on Steiner triple systems obtained from projective geometry. Our objects are subgeometries as blocks. These subgeometries are collected into systems and we study them as designs and graphs. Considered recursively is a further tactical con guration on some of the designs obtained and in what follows, we obtain similar structures as the Steiner triple systems from projective geometry. We also study these subgeometries as factorizations and examine the automorphism group of the new structures. These tactical con gurations at rst sight do not form interesting structures. However, as will be shown, they o er some level of intriguing symmetries. It will be shown that they inherit the automorphism group of the parent geometry.
62

Das terras dos índios a índios sem terras. O Estado e os Guarani do Oco\'y: violência, silêncio e luta / From the Indian lands to the Indians with no land. The Guarani do Oco\'y\'s route: violence, silence and fight

Carvalho, Maria Lucia Brant de 01 October 2013 (has links)
A população indígena Guarani desde tempos imemoriais ocupa tradicionalmente as Bacias do Rio Paraguai, Paraná e Uruguai e seus afluentes, ou seja, a grande Bacia do Prata. A região da Bacia do Paraná na Tríplice Fronteira entre Brasil, Paraguai e Argentina é denominada pelos Guarani como sendo uma parcela do Tekoa Guassu (conjunto de várias aldeias Guarani ou Aldeia Grande). Ali possuem o direito de permanecer, reconhecido legalmente desde a época colonial portuguesa e pelas sucessivas constituições brasileiras. No decorrer do século XX com a instalação de empreendimentos estatais brasileiros na região do oeste paranaense, os Guarani foram esbulhados de suas terras desaparecendo assim, inúmeras aldeias. Instalou-se um processo de desconstrução do território indígena. Grande parte da população indígena foi expulsa para o Paraguai, concentrando-se junto às aldeias ali existentes, localizadas na fronteira com o Brasil. Apesar das pressões, uma única população Guarani conseguiu resistir no Brasil. Trata-se dos habitantes da antiga aldeia do Ocoy-Jacutinga. Em 1973, ela teve a maior parte de suas terras ocupadas pelo INCRA, visando reassentar colonos retirados do Parque Nacional do Iguaçu. Em 1982 a parte restante do território indígena, foi totalmente inundada com a construção da Usina Hidrelétrica de Itaipu. Somente parte dos indígenas foram compulsoriamente reterritorializados para a Terra Indígena Avá-Guarani do Ocoy. A transferência da população, legalmente deveria ser de todo o agrupamento indígena, para terras de igual extensão e ambientalmente semelhantes à anterior, e ainda seu uso deveria ser exclusivo. Ocoy apresenta dimensões diminutas, menores que a anterior e ambientalmente comprometida. É sobreposta à Área de Preservação Permanente do reservatório da Usina Hidrelétrica de Itaipu, terras em que, antes, constituía-se parte de Glebas de Colonos, os quais não foram indenizados pelo INCRA. Dada a insuficiência de terras e os problemas sociais decorrentes das superposições, os Guarani sofrem toda sorte de impactos sociais, ambientais, econômicos e sanitários. Tentativas de reterritorialização por parte dos indígenas foram reprimidas pelo Estado. Encontram-se acuados e necessitam de terras em ambiente adequado para sua reprodução física e cultural. Para esta solução, é preciso descartar falsas versões, que atribuem à emigração de indivíduos Guarani provenientes do Paraguai, a existência de excesso demográfico no Ocoy. Esta assertiva vem sendo utilizada, impedindo e mascarando a resolução do problema fundiário. O crescimento demográfico no Ocoy é semelhante ao de qualquer aldeia da etnia. Na verdade, não é a população indígena que é excessiva, mas o território onde foi reassentada que se apresenta insuficiente e inadequado desde a sua instalação no local. Tal situação é fruto de histórico descumprimento das leis pelos poderes Executivo e Judiciário federais, favorecendo grupos de poder locais. / Traditionally, since memorable times, the Paraguay, Paraná and Uruguay Bays and their tributaries, known as the greater Prata Bay, have been occupied by the Guarani Indian population. The Paraná Bay in the triple border between Brazil, Paraguay and Argentina is identified by part of the Guarani as Tekoa Guassu (a cluster of many Guarani villages or Big Village). Their right to live there is legally recognized by the consecutive Brazilian Constitutions since Portuguese Colonial Times. During the 20th century the Guarani were evicted from their lands due to the Brazilian governments enterprises in the west region of the Paraná State which caused the disappearance of countless villages. It initiated a process of dissipating the Indian Territory. Great part of the Indian population was pushed to Paraguayan lands in the border with Brazil where other villages already existed. In spite of that, one Guarani population, the inhabitants of the old village known as Ocoy-Jacutinga managed to resist in Brazilian territory. However, in 1973, the majority of its lands was occupied by INCRA, to resettle colonists that were withdrawn from Iguaçu National Park. In 1982 the remaining part of the Indian Territory was completely flooded with the construction of Itaipu Hydroelectric Power Plant. Only part of the Indians were compulsorily relocated to the Indian Land of Avá-Guarani do Ocoy. Legally the transference of that population should be for whole Indian group to lands of the same extension and environmentally similar to the previous ones with exclusive occupation. Ocoy, conversely, presents diminutive dimensions, smaller than the preceding one and environmentally impaired. It is overlaped by the Area of Permanent Preservation of Itaipu Hydroelectric Power Plant reservoir; lands that were previously part of the colonist areas, which were not reimbursed by INCRA. Due to the small quantity of land and the social problems developed by the overlapping, the Guarani Indians suffer all kinds of social, environmental, economic and sanitary impact. Indian resettlement attempts were restrained by the State. They are cornered and need the land in a proper environment for their physical and cultural reproduction. For a solution to that matter, it is necessary to throw away false versions that attribute emigration of Guarani Indians from Paraguay due to demographic excess in Ocoy. The use of such statement is an impediment to the resolution for the land property problem. The demographic growth in Ocoy is similar to any other of its ethnic villages. Actually, it is not the Indian population that is excessive but the place where they were resettled that is insufficient and inadequate from the start. Those circunstances are a consequence of the historical unbinding of the law from the Brazilian Judiciary and Executive Federal Institutions on behalf of local power groups.
63

Role of oxidative stress in the pathogenesis of triple A syndrome and familial glucocorticoid deficiency

Prasad, Rathi January 2014 (has links)
Maintaining redox homeostasis is crucial for normal cellular functions. Electron leak by the cytochrome P450 enzymes renders steroidogenic tissues acutely vulnerable to redox imbalance and oxidative stress is implicated in several potentially lethal adrenal disorders. This thesis aims to further delineate the role of oxidative stress in triple A syndrome and familial glucocorticoid deficiency (FGD). Triple A syndrome incorporates adrenal failure and progressive neurodegenerative disease. The AAAS gene product is the nuclear pore complex protein ALADIN, of unknown function. Patient dermal fibroblasts are sensitive to oxidative stress, with failure of nuclear import of DNA repair proteins and ferritin heavy chain protein. To provide an adrenal and neuronal-specific disease model, I established AAAS-knockdown in H295R human adrenocortical tumour cells and SH-SY5Y human neuroblastoma cells. This had effects on cell viability, exacerbated by hydrogen peroxide treatment. Redox homeostasis was impaired in AAAS-knockdown H295R cells, with depletion of key components of the steroidogenic pathway and a significant reduction in cortisol production, with partial reversal following treatment with N-acetylcysteine. Mutations in the mitochondrial antioxidant, nicotinamide nucleotide transhydrogenase (NNT), causing FGD, have recently highlighted the importance of redox regulation in steroidogenesis. I investigated seven individuals from a consanguineous Kashmiri kindred, mutation negative for known causes of FGD. A stop gain mutation, p.Y447* in TXNRD2, encoding the mitochondrial selenoprotein thioredoxin reductase 2 segregated with the disease trait; with complete absence of the 56 kDa TXNRD2 protein in patients homozygous for the mutation. TXNRD2-knockdown led to impaired redox homeostasis in H295R cells. This is the first report of a homozygous mutation in any component of the thioredoxin antioxidant system leading to inherited disease in humans.
64

Enhancing triple phase boundary electrosynthesis

Watkins, John D. January 2011 (has links)
The first part of this thesis is concerned with the synthesis, characterisation and applications of surface functionalised carbon nanoparticles. Synthetic techniques are used to modify the existing surface architecture of carbon nanoparticles towards high surface area modified electrodes and pH sensing applications. Electrochemical and synthetic techniques have been used to study triple phase boundaries and enhance their properties towards a bulk synthetic technique, in which an electrolyte phase and redox probe phase are held separate. A salt matrix, ultrasound, high shear force and a carbon fibre membrane have all been used to form unique triple phase boundary environments in which electron and ion transfer processes can be studied and enhanced towards analytical and electrosynthetic applications. A number of electro-reduction reactions have been shown to be feasible using the triple phase boundary methodology. Alkenes, aldehydes and imines have all been successfully electro-reduced, analysed and optimised to elucidate the synthetic triple phase boundary mechanism.
65

The Triple Bottom Line: A Study into Corporate Social Responsibility and Sustainability Accounting Trends

Aung, Moe Myat 01 January 2019 (has links)
Sustainability within the spheres of environmental and social awareness have become increasing salient issues in the world today. This is addressed within the corporate world through Corporate Social Responsibility (CSR) disclosure and reporting. However, the reporting and disclosure surrounding such issues remains at a disadvantage in comparison to that of financial reporting. These issues not only govern sustainability and awareness itself but increasing investor and stakeholder decisions concerning firms connected to these issues. This thesis aims to explore the issues encountered today in CSR reporting. It reviews current literature on regional differences, current methods of CSR disclosure, and the drawbacks of current reporting standards. To address these topics, there is a review of the definition of a stakeholder, its development over time and how stakeholders are prioritized and affected by the actions of firms. With the definition of a stakeholder established, the thesis reviews the relationship between different stakeholders and CSR disclosure and how this can be applied in order to increase the quality and consistency of CSR reporting. Finally, trends in CSR and differences within sectors and regions are considered and it is determined that there has to be a development of standardization through a current reporting standard, in order to ensure congruency of information across nations and sectors, allowing investors and stakeholders to make better informed decisions through the provided sustainability information.
66

Värderingsbaserat värdeskapande : En studie vid HSB Centrala Värmland / Values-based Valuecreation : A Study at HSB Centrala Värmland

Engblom, Alexandra, Eriksson, Veronica January 2007 (has links)
Syftet med denna uppsats är att undersöka hur HSBs värderingar skapar värde för HSBs intressenter. För att undersöka detta har vi använt oss av en kvalitativ metod. Denna grundar sig i en syn på verkligheten som social konstruktion och en hermeneutisk, tolkande, syn på kunskap. Undersökningen är gjord vid HSB Centrala Värmland i Karlstad. Företag söker ständigt nya sätt att skapa värde. Värde anses idag vara något som skapas tillsammans, genom relationer och att enbart fokusera på ägare och att göra vinst är således inte längre tillräckligt. Ett företag måste ta hänsyn till samtliga av sina intressenter och lära sig vad som skapar värde för dem. På senare tid är det intresset för sociala, etiska och miljömässiga värderingar ökat. Begrepp som socialt ansvar och hållbarhet blir allt viktigare och dessa aktiviteter verkar kunna styras precis som andra system inom ett företag. Värderingar kan vidare vara drivande faktorer i förbättringsprocesser vad gäller tjänstekvalitet, så kallad värderingsbaserad tjänstekvalitet för hållbara affärer. Slutsatsen av undersökningen är att HSBs värderingar, engagemang, trygghet, hållbarhet, omtanke och samverkan, ETHOS, skapar värde för HSBs intressenter och särskiljer HSB från andra företag på marknaden genom att de genomsyrar hela HSBs verksamhet och kan kopplas till allt HSB gör. Avgörande i denna process är framför allt den interna kommunikationen. HSBs medarbetare definierar värderingarna, ETHOS, som sina egna och agerar enligt dem vilket, som ovan nämnt, ger värderingarna innehåll. Genom att lyssna på sina intressenter, och ge dem vad de vill ha och förväntar sig, driver och förbättrar värderingarna tjänstekvaliteten. HSB som är en kooperativ organisation har en större möjlighet att komma nära sina intressenter och därmed att förstå vilka värderingar dessa har, än andra privat- eller aktieägdaföretag, vilket måste anses som en fördel.
67

Alterations of the Monoaminergic Systems by Sustained Triple Reuptake Inhibition

Jiang, Jojo L 21 August 2012 (has links)
Recent approaches in depression therapeutics include triple reuptake inhibitors, drugs that target three monoamine systems. Using in vivo electrophysiological and microdialysis techniques, the effects of 2- and 14-day treatments of escitalopram, nomifensine and the co-administration of these two drugs (TRI) were examined in male Sprague-Dawley rats. Short- and long-term TRI administration decreased NE firing and had no effect on DA neurons. Normal 5-HT firing rates were maintained after 2-day TRI administration compared to the robust inhibitory action of selective serotonin reuptake inhibitors (SSRIs). Escitalopram treatment enhanced the tonic activation of the 5-HT1A receptors given the increase in firing observed following WAY100635 administration. Nomifensine treatment enhanced tonic activation of the α2–adrenoceptors following idazoxan administration. TRI treatment caused a robust increase in extracellular DA levels that was in part mediated by a serotonergic contribution. Therapeutic effects of the drugs examined in this study may be due to the enhancement of 5-HT, NE and/or DA neurotransmission.
68

Sustainable development in ecotourism : Tour operators managing the economic, social and environmental concerns of sustainable development in Costa Rica

Eriksson, Frida, Lidström, Matilda January 2013 (has links)
Sustainable development is concerned with acknowledging economic, social and environmental development aspects, catering for the current needs of society without damaging the well-being of future generations. Ecotourism is a niche market that emerged because of increased market demands for sustainable tourism practices. It serves to provide tourism products and services while accommodating for the economic, social and environmental aspects of society. However, earlier research suggests that it is difficult to handle the three dimensions of sustainable development, indicating that trade-offs may occur. Furthermore, as tour operators are able to affect local development prospects, it is of interest to examine how they handle sustainable development, and more specifically, contribute to trade-offs between the economic, social and environmental pillars of sustainable development. This thesis was aimed at answering the following research question; “How do ecotourism tour operators contribute to trade-offs between the economic, social and environmental dimensions of sustainable development?”, with the objective of examining how ecotourism tour operators handle the dimensions of sustainable development, and what trade-offs that may occur between economic, social and environmental concerns. This qualitative research was carried out in the context of ecotourism tour operators in Costa Rica through semi-structured interviews. Nine respondents participated in this research, representing seven local ecotourism tour operators. The data collected on the trade-offs of ecotourism and sustainable development has in turn been analysed with reference to a pre-established theoretical framework. This study has revealed that ecotourism tour operators are actively engaging in initiatives supporting the idea of sustainable development. The tour operators handle the economic, social and environmental concerns through different initiatives. One conclusion that can be derived from this research is that all pillars of sustainable development are important to acknowledge. However, this is difficult as the three dimensions are somewhat contradicting. Therefore, depending on how ecotourism tour operators prioritise different initiatives, trade-offs are inevitable as both inter- and intragenerational needs are difficult to align.
69

A Triple-Porosity Model for Fractured Horizontal Wells

Alahmadi, Hasan Ali H. 2010 August 1900 (has links)
Fractured reservoirs have been traditionally idealized using dual-porosity models. In these models, all matrix and fractures systems have identical properties. However, it is not uncommon for naturally fractured reservoirs to have orthogonal fractures with different properties. In addition, for hydraulically fractured reservoirs that have preexisting natural fractures such as shale gas reservoirs, it is almost certain that these types of fractures are present. Therefore, a triple-porosity (dual-fracture) model is developed in this work for characterizing fractured reservoirs with different fractures properties. The model consists of three contiguous porous media: the matrix, less permeable micro-fractures and more permeable macro-fractures. Only the macro-fractures produce to the well while they are fed by the micro-fractures only. Consequently, the matrix feeds the micro-fractures only. Therefore, the flow is sequential from one medium to the other. Four sub-models are derived based on the interporosity flow assumption between adjacent media, i.e., pseudosteady state or transient flow assumption. These are fully transient flow model (Model 1), fully pseudosteady state flow model (Model 4) and two mixed flow models (Model 2 and 3). The solutions were mainly derived for linear flow which makes this model the first triple-porosity model for linear reservoirs. In addition, the Laplace domain solutions are also new and have not been presented in the literature before in this form. Model 1 is used to analyze fractured shale gas horizontal wells. Non-linear regression using least absolute value method is used to match field data, mainly gas rate. Once a match is achieved, the well model is completely described. Consequently, original gas in place (OGIP) can be estimated and well future performance can be forecasted.
70

Capillary electrophoresis with triple pulsed amperometric detection at gold microelectrode for mercury speciation

Huang, Wen-Shiuan 30 August 2008 (has links)
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