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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.
31

Proposta de extensão do protocolo PCE considerando parâmetros de QoT para roteamento inter-domínios em redes GMPLS. / Proposal for a PCE protocol extension considering QoT parameters to be used in inter-domain routing in GMPLS networks.

Ricardo Girnis Tombi 30 August 2007 (has links)
Este trabalho apresenta uma análise sobre a Arquitetutra PCE (Path Computation Element), como alternativa para o roteamento inter-domínios em redes heterogêneas, ou seja, em ambientes onde ocorre a integração do domínio óptico, das redes de transporte ópticas, com o domínio eletrônico, das redes convencionais, tratando inclusive com questões de qualidade de transmissão do sinal óptico, ou QoT (Quality of Transmission). Os objetivos e o funcionamento do mecanismo do PCE em redes integradas são detalhados. São apresentados também os conceitos e definições das redes ópticas, bem como seus principais elementos, a proposta de interconexão das mesmas com as redes convencionais provendo uma rede única e integrada, o papel dos planos de controle, e os principais mecanismos de roteamento. A análise do PCE foi direcionada para o comportamento do principal protocolo utilizado na sua arquitetura, denominado PCE Protocol. De forma mais específica, foi realizada a análise de suas mensagens de requisição de rotas e das mensagens de respostas a estas requisições, e sua interferência no tráfego dos enlaces das redes onde são introduzidas. A partir daí é apresentada uma proposta de extensão de parâmetros para o protocolo PCE Protocol, com o objetivo de atender necessidades específicas de QoT, baseado em estudos das particularidades das características das transmissões ópticas. A partir destas definições, foram realizadas análises adicionais a fim de verificar o impacto com relação ao tráfego gerado em enlaces de diferentes larguras de banda, com a definição original do protocolo, e com a extensão proposta, permitindo uma comparação entre ambos. / This thesis presents an analysis of Path Computation Element Architecture (PCE) as an alternative to be implemented in heterogeneous network inter-domain routing, in other words, environments where optical domains are integrated with the electronic domains of conventional networks. Also, the ability of PCE to manage issues regarding the transmission quality of the optical signal, the QoT (Quality of Transmission), is presented. Objectives and functionality of the PCE mechanism in integrated networks is detailed. Concepts and definitions regarding optical networks and their main elements, the aim of interconnection with conventional networks to build a unified and integrated network, the role of control planes, and the main routing mechanisms are also presented. The analysis of the PCE was focused on the behavior of its main protocol, called PCE Protocol. Specifically, the analysis was performed on both its request and response messages, in addition, the interference in the traffic of the links where these messages had been introduced was also analyzed. Afterwards, an extension of the PCE Protocol parameters was proposed based on the study of optical transmission characteristics, with the aim of meeting specific QoT requirements. From these definitions, further analyses of the impact on the traffic in links with different bandwidths were performed, using the PCE protocol, with and without the proposed extension, allowing a comparison between them.
32

Interdomain traffic engineering with MPLS

Pelsser, Cristel 10 November 2006 (has links)
During the last years, MultiProtocol Label Switching (MPLS) has been deployed by most large Service Providers (SP). The main driver for MPLS deployment is the ability to provide new services with stringent Service Level Agreements (SLAs) such as layer-2 and layer-3 Virtual Private Networks (VPNs) as well as Voice and Video over IP. Most of these services are already deployed inside single SP networks. However, customers now require world-wide VPN and VoIP services. Therefore, SPs need to collaborate to offer these services across multiple SP networks. Inside a single SP network, each node usually knows the complete topology of the network with the load and delay of all the links. Based on this information, each router is able to compute constrained paths toward any other router inside the SP network. Then, it can establish a connection and reserve resources along the computed path with the Resource reSerVation Protocol (RSVP-TE). However, when services with stringent requirements must cross multiple SP networks the computation of the path becomes a problem. Routers in different SP networks exchange routing information by using the Border Gateway Protocol (BGP). BGP provides reachability information. It does not distribute complete topology, delay and bandwidth information. One way to provide guaranteed services crossing different SPs is to delegate the computation of the paths to a Path Computation Element (PCE) that learns the topology of the different SPs. However, this requires that SPs reveal information that they usually consider confidential, their topology. In this thesis, we perform active measurements to show the difficulty to engineer the interdomain traffic with BGP. MPLS together with RSVP-TE provide much more control on the traffic. We define extensions to RSVP-TE for the protection of inter-AS MPLS paths. The aim is to be able to provide the same service guarantees as inside a domain while keeping the internal topology of SPs confidential, as required by SPs. We propose and evaluate distributed techniques relying on PCEs for the computation of interdomain constrained paths respecting the latter confidentiality requirement.
33

Application of two dimensional compound specific carbon-chlorine isotope analyses for degradation monitoring and assessment of organic pollutants in contaminated soil and groundwater

Wiegert, Charline January 2013 (has links)
Nearly 250,000 sites with past and present potentially polluting activities need urgent remediation within Europe. Major pollutants include organochlorines (OCls), e.g. chlorinated ethenes (CEs) and hexachlorocyclohexanes (HCHs), mainly used as industrial solvents and pesticides, respectively. Due to improper handling and disposal, OCls contaminants are present in the soil or groundwater surrounding sites, where they have been produced or used. CEs and HCHs can undergo degradation by microorganisms indigenous to the soil or groundwater. Therefore natural attenuation (NA), relying on the in situ biodegradation of pollutants, is considered as a cost effective remediation strategy, yet it requires accurate monitoring methods. Compound specific isotope analysis (CSIA) is a powerful tool to provide information on the extent of degradation and, when combining two isotope systems (2D-CSIA), such as carbon (δ13C) and chlorine (δ37Cl), on reaction mechanisms. The diagnostic reaction-specific isotope enrichment factors (εC and εCl) were determined in laboratory experiments for the anaerobic degradation of PCE, TCE (Paper II) and α-HCH (Paper III) by mixed bacterial cultures enriched from CEs and HCHs contaminated sites, respectively. The related mechanism-specific εCl/εC ratios were calculated as 0.35 ± 0.11 (PCE), 0.37 ± 0.11 (TCE) and 0.52 ± 0.23 (α-HCH). These values are smaller than previously reported values for pure cultures. This is explained by the microbial community composition changes observed during degradation of PCE and α-HCH, which also reflect the variability of the microbial community at the field level. Furthermore, εCl/εC ratio might be bacteria specific. These values allowed the estimation of the extent of contaminant degradation at the respective study sites (Paper III and IV). Application of both isotope systems (δ13C and δ37Cl) led to comparable estimates. However the choice of representative ε values is crucial for an accurate assessment. These studies show that CSIA is useful to quantify in situ degradation of OCls contaminants and identify reaction pathways, by combining δ13C and δ37Cl. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Submitted. Paper 4: Manuscript.</p>
34

A temática ambiental no contexto escolar: abordagens adotadas em projetos do Programa Ciência na Escola no Amazonas

Milhomem, Karina de Oliveira, 92-99265-8534 28 July 2017 (has links)
Submitted by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2018-05-11T15:53:08Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertação_Karina O. Milhomem.pdf: 1245608 bytes, checksum: e0b7ca4cd733a56f5c56c065d05b5ec7 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2018-05-11T15:53:20Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertação_Karina O. Milhomem.pdf: 1245608 bytes, checksum: e0b7ca4cd733a56f5c56c065d05b5ec7 (MD5) / Made available in DSpace on 2018-05-11T15:53:20Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertação_Karina O. Milhomem.pdf: 1245608 bytes, checksum: e0b7ca4cd733a56f5c56c065d05b5ec7 (MD5) Previous issue date: 2017-07-28 / FAPEAM - Fundação de Amparo à Pesquisa do Estado do Amazonas / We believe that education constitutes a powerful intervention tool in the world for the construction of new concepts and consequent change of habits. In this sense, environmental education proposes the construction of a responsible citizenship, stimulating fairer interactions between human beings and the other beings that inhabit the Planet, for the construction of a present and a sustainable, healthy and socially fair fuure. The objective of this paper was to investigate the presence of the environmental theme in public schools in Amazonas under the Science in School Program (PCE), an initiative of the Foundation for Research Support in Amazonas (FAPEAM), which aims to stimulate the scientific literacy of basic education of public schools and the involvement of their teachers with scientific practice. A total of 61 projects developed in 2014 and 2015 in public schools in the capital of Manaus and in nine municipalities (Atalaia do Norte, Borba, Coari, Iranduba, Itacoatiara, Nhamundá, Parintins, Tabatinga and Tefé) were analyzed in which was brought the theme of environment as their object of research. The results presented here were obtained from the analysis of edicts, decisions, projects and their respective reports. It could be noticed that this theme is not a priority in the projects developed, since only 8% of them, in the years of 2014 and 2015, brought this approach as a research theme. The most worked topics were garbage (28%), recycling (21%), environmental issues (16%), water (10%) and composting (10%). The majority of these projects were developed in Manaus (62%), in schools administered by the State Department of Education - SEDUC (83%) and with high school students (56%). Most of these projects were linked to the disciplines of Biology (26%), Geography (26%) and Science (19%). The main means used to carry out the activities were: bibliographic survey, workshops, collections and videos. The teachers coordinating the projects are mostly female (75%). All the professors have completed higher education, of which 31% have a postgraduate level of specialization (Lato Sensu) and 9% have a master's degree. Among the three politicalpedagogical macro-trends of Environmental Education, the pragmatic macro-trend was the one that stood out among the projects analyzed, followed by conservationist and critical. / Acreditamos que educação constitui-se como uma poderosa ferramenta de intervenção no mundo para a construção de novos conceitos e consequente mudança de hábitos. Neste sentido, a educação ambiental propõe a construção de uma cidadania responsável, estimulando interações mais justas entre os seres humanos e os demais seres que habitam o Planeta, para a construção de um presente e um futuro sustentável, sadio e socialmente justo. O objetivo deste trabalho foi averiguar a presença da temática ambiental nas escolas públicas do Amazonas no âmbito do Programa Ciência na Escola - PCE, que é uma iniciativa da Fundação de Amparo à Pesquisa no Amazonas-FAPEAM, que objetiva estimular a alfabetização cientifica de alunos da educação básica de escolas públicas e o envolvimento de seus professores com a prática científica. Foram analisados 61 projetos desenvolvidos nos anos de 2014 e 2015 em escolas públicas da capital Manaus e em nove municípios (Atalaia do Norte, Borba, Coari, Iranduba, Itacoatiara, Nhamundá, Parintins, Tabatinga e Tefé), que traziam a temática ambiental como objeto de pesquisa. Os resultados aqui apresentados foram obtidos a partir da análise de editais, decisões, projetos e seus respectivos relatórios. Pôde-se observar que esta temática não é prioridade nos projetos desenvolvidos, pois somente 8% deles, nos anos de 2014 e 2015, trouxeram esta abordagem como tema de pesquisa. As temáticas mais trabalhadas foram lixo (28%), reciclagem (21%), questões ambientais (16%), água (10%) e compostagem (10%). A grande maioria destes projetos foi desenvolvida em Manaus (62%), em escolas administradas pela Secretaria de Estado de Educação - SEDUC (83%) e com alunos do ensino médio (56%). A maior parte destes projetos estava vinculada às disciplinas de Biologia (26%), Geografia (26%) e Ciências (19%). Os principais meios utilizados para realização das atividades foram: levantamento bibliográfico, oficinas, coletas e vídeos. Os professores coordenadores dos projetos são em sua maioria do sexo feminino (75%). Todos os professores possuem formação superior completa, dos quais 31% possuem pós-graduação em nível de especialização (Lato Sensu) e 9% possuem titulação de mestre. Dentre as três macrotendências políticopedagógicas de Educação Ambiental, a macrotendência pragmática foi a que se destacou entre os projetos analisados, seguida da conservacionista e crítica.
35

Genotoxicidade e citotoxicidade de corantes azóicos em ensaio do micronúcleo in vivo (Swiss albinus) / Genotoxicity and cytotoxicity of azodyes in the in vivo micronucleus test (Swiss albinus) / Genotoxicidade e citotoxicidade de corantes azóicos em ensaio do micronúcleo in vivo (Swiss albinus)

SOUZA, Carolina C. S. H. 25 February 2015 (has links)
Submitted by biblioteca unifenas (biblioteca@unifenas.br) on 2017-08-24T13:10:32Z No. of bitstreams: 1 Carolina Soares Horta de Souza.pdf: 898395 bytes, checksum: 8025b51d63570bf92cd6485289fa3c65 (MD5) / Made available in DSpace on 2017-08-24T13:10:32Z (GMT). No. of bitstreams: 1 Carolina Soares Horta de Souza.pdf: 898395 bytes, checksum: 8025b51d63570bf92cd6485289fa3c65 (MD5) Previous issue date: 2015-02-25 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The addition of the food coloring plays an important role in the food industry under the technological point of view. Natural dyes are difficult to navigate in standard products, so we were created synthetic dyes. Among artificial synthetic dyes allowed by law, are those of azo group and its use is one of the most controversial developments in the sector. The use of these substances is still raising a lot of questions as to toxicity, because in the literature, working with this momentum is limited and controversial. In this context, the aim, with this study was to evaluate the genotoxic potential of azo dyes by the micronucleus assay (MN). The MN test is widely used and internationally accepted for evaluation of mutagenic actions. The in vivo genotoxicity test was applied to research observed in erythrocytes Polychromatic (PCE) extracted from the bone marrow of the femur 168 Swiss mice Albinus, male and female, underwent five treatments (N-nitroso-N-ethylurea: control+; 150 mM NaCl: Control–; dye at 1, 1.5 and 2 g.Kg-1) and used four azo dyes (Tartrazine, Sunset Yellow, Red 40, Ponceau 4R) for 24h and 48h (after this time euthanasia was performed). We analyzed also the PCE/NCE ratio, which it is an important marker of cytotoxicity. The data obtained in the MN assay were subjected to analysis of one-way variance (ANOVA) using a factorial scheme of 5 × 2 × 2 (treatment × sex × time), and average compared to Tukey's test (p < 0.05) using SAS® software version 9.3. The dye Tartrazine showed genotoxicity dose- and sex-dependent; Sunset Yellow was genotoxic sex-independent; Red 40, its genotoxicity was dependent on the exposure time and the sex of the animal; the dye Ponceau 4R genotoxicity depends on the dose and time until euthanasia. However, it can be concluded that studies of these food additives often must be performed in order to constantly update data that are safe for consumption, since all four dyes tested in this study showed some degree of toxicity. Recalling that they have the use regulated by specific legislation establishing the Maximum Allowable Limits (LMP) and patterns of Acceptable Daily Intake for humans, extrapolated to animals. However, despite the control required by regulatory agencies, the use of dyes in food continues to raise a number of questions, mainly due to lack of studies evaluating the toxicity of these compounds which reinforces the attention they should be given. / A adição de corantes em alimentos e rações assume papel importante na indústria alimentícia sob o ponto de vista tecnológico. Corantes naturais são difíceis de serem utilizados em produtos padronizados, portanto, foram criados corantes sintéticos. Dentre os corantes sintéticos artificiais permitidos por lei, estão aqueles do grupo Azo e seu uso é um dos avanços mais controversos no setor. A utilização destas substâncias continua levantando uma série de dúvidas quanto à toxicidade, uma vez que, na literatura, trabalhos com esse ímpeto são escassos e controversos. Neste contexto, objetivou-se, com este trabalho, avaliar o potencial genotóxico de corantes azóicos através do ensaio de micronúcleo (MN). O teste do MN é amplamente utilizado e aceito internacionalmente para avaliação de ações mutagênicas. O teste in vivo foi aplicado para investigação de genotoxicidade observada em Eritrócitos Policromáticos (PCE) extraídos da medula óssea do fêmur de 168 camundongos Swiss albinus, machos e fêmeas, submetidos a cinco tratamentos (N-Nitroso-N-etilureia: controle+; 150 mM NaCl: controle–; corante a 1, 1,5 e 2 g.Kg-1), sendo utilizados quatro corantes azóicos (Tartrazina, Amarelo Crepúsculo, Vermelho 40, Ponceau 4R) nos tempos de 24h e 48h (após estes períodos foi executada eutanásia). Foi analisada também a relação PCE/NCE, cujo se trata de um importante biomarcador de citotoxicidade. Os dados obtidos no ensaio de MN foram submetidos à análise de variância (ANOVA), utilizando um esquema fatorial de 5 × 2 × 2 (tratamento × sexo × tempo), e comparação das médias pelo teste de Tukey (p < 0,05) usando o programa computacional SAS® versão 9.3. O corante Tartrazina apresentou genotoxicidade dose e sexo dependentes; Amarelo Crepúsculo foi genotóxico independente do sexo; Vermelho 40, a sua genotoxicidade foi dependente do tempo de exposição e do sexo do animal; a genotoxicidade do corante Ponceau 4R foi dependente da dose administrada e do tempo até a eutanásia. Contudo, pode-se concluir que estudos envolvendo estes aditivos alimentares devem ser realizados frequentemente com a finalidade de atualização constante de dados que ofereçam segurança para seu consumo, uma vez que todos os quatro corantes testados nesta pesquisa apresentaram algum grau de toxicidade. Lembrando que os mesmos possuem o uso regulamentado por legislação específica, que estabelece os Limites Máximos Permitidos (LMP) e padrões de Ingestão Diária Aceitável por humanos, extrapolados para animais. Porém, apesar do controle exigido pelas agências reguladoras, a utilização de corantes em alimentos continua levantando uma série de dúvidas, principalmente devido a escassez de trabalhos avaliando a toxicidade destes compostos o que reforça a atenção que lhes deve ser conferida.
36

THE COMMUNITY STRUCTURE OF METHANOGENIC, METHANOTROPHIC, AND AMMONIA OXIDIZING BACTERIA IN VERTICAL FLOW GREENHOUSE WETLAND MESOCOSMS EXPOSED TO PCE

Gruner, William Evan January 2008 (has links)
No description available.
37

Evaluation of groundwater flow and contaminant transport at the Wells G&H Superfund Site, Woburn, Massachusetts, from 1960 to 1986 and estimation of TCE and PCE concentrations delivered to Woburn residences

Metheny, Maura A. 20 July 2004 (has links)
No description available.
38

Study of translation control by a RNA helicase A-responsive post-transcriptional control element in Retroviridae

Bolinger, Cheryl Giles 21 November 2008 (has links)
No description available.
39

Biodegradation of Aliphatic Chlorinated Hydrocarbon (PCE, TCE and DCE) in Contaminated Soil.

Tibui, Aloysius January 2006 (has links)
<p>Soil bottles and soil slurry experiments were conducted to investigate the effect of some additives on the aerobic and anaerobic biodegradation of chlorinated aliphatic hydrocarbons; tetrachloroethylene (PCE), trichloroethylene (TCE) and dichloroethylene (DCE) in a contaminated soil from Startvätten AB Linköping Sweden. For the aerobic degradation study the soil sample was divided into two groups, one was fertilised. The two groups of soil in the experimental bottles were treated to varying amount of methane in pairs. DCE and TCE were added to all samples while PCE was found in the contaminated soil. Both aerobic and anaerobic experiments were conducted. For aerobic study air was added to all bottles to serve as electron acceptor (oxygen). It was observed that all the samples showed a very small amount of methane consumption while the fertilised soil samples showed more oxygen consumption. For the chlorinated compounds the expected degradation could not be ascertained since the control and experimental set up were more or less the same.</p><p>For the anaerobic biodegradation study soil slurry was made with different media i.e. basic mineral medium (BM), BM and an organic compound (lactate), water and sulphide, phosphate buffer and sulphide and phosphate buffer, sulphide and ammonia. To assure anaerobic conditions, the headspace in the experimental bottles was changed to N2/CO2. As for the aerobic study all the samples were added DCE and TCE while PCE was found in the contaminated soil. The sample without the soil i.e. the control was also given PCE. It was observed that there was no clear decrease in the GC peak area of the pollutants in the different media. The decrease in GC peak area of the pollutants could not be seen, this may be so because more susceptible microorganisms are required, stringent addition of nutrients and to lower the risk of the high concentration of PCE and petroleum products in the soil from Startvätten AB.</p>
40

Biodegradation of Aliphatic Chlorinated Hydrocarbon (PCE, TCE and DCE) in Contaminated Soil.

Tibui, Aloysius January 2006 (has links)
Soil bottles and soil slurry experiments were conducted to investigate the effect of some additives on the aerobic and anaerobic biodegradation of chlorinated aliphatic hydrocarbons; tetrachloroethylene (PCE), trichloroethylene (TCE) and dichloroethylene (DCE) in a contaminated soil from Startvätten AB Linköping Sweden. For the aerobic degradation study the soil sample was divided into two groups, one was fertilised. The two groups of soil in the experimental bottles were treated to varying amount of methane in pairs. DCE and TCE were added to all samples while PCE was found in the contaminated soil. Both aerobic and anaerobic experiments were conducted. For aerobic study air was added to all bottles to serve as electron acceptor (oxygen). It was observed that all the samples showed a very small amount of methane consumption while the fertilised soil samples showed more oxygen consumption. For the chlorinated compounds the expected degradation could not be ascertained since the control and experimental set up were more or less the same. For the anaerobic biodegradation study soil slurry was made with different media i.e. basic mineral medium (BM), BM and an organic compound (lactate), water and sulphide, phosphate buffer and sulphide and phosphate buffer, sulphide and ammonia. To assure anaerobic conditions, the headspace in the experimental bottles was changed to N2/CO2. As for the aerobic study all the samples were added DCE and TCE while PCE was found in the contaminated soil. The sample without the soil i.e. the control was also given PCE. It was observed that there was no clear decrease in the GC peak area of the pollutants in the different media. The decrease in GC peak area of the pollutants could not be seen, this may be so because more susceptible microorganisms are required, stringent addition of nutrients and to lower the risk of the high concentration of PCE and petroleum products in the soil from Startvätten AB.

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