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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.
261

Deploying Monitoring Trails for Fault Localization in All-optical Networks and Radio-over-Fiber Passive Optical Networks

Maamoun, Khaled M. 24 August 2012 (has links)
Fault localization is the process of realizing the true source of a failure from a set of collected failure notifications. Isolating failure recovery within the network optical domain is necessary to resolve alarm storm problems. The introduction of the monitoring trail (m-trail) has been proven to deliver better performance by employing monitoring resources in a form of optical trails - a monitoring framework that generalizes all the previously reported counterparts. In this dissertation, the m-trail design is explored and a focus is given to the analysis on using m-trails with established lightpaths to achieve fault localization. This process saves network resources by reducing the number of the m-trails required for fault localization and therefore the number of wavelengths used in the network. A novel approach based on Geographic Midpoint Technique, an adapted version of the Chinese Postman’s Problem (CPP) solution and an adapted version of the Traveling Salesman’s Problem (TSP) solution algorithms is introduced. The desirable features of network architectures and the enabling of innovative technologies for delivering future millimeter-waveband (mm-WB) Radio-over-Fiber (RoF) systems for wireless services integrated in a Dense Wavelength Division Multiplexing (DWDM) is proposed in this dissertation. For the conceptual illustration, a DWDM RoF system with channel spacing of 12.5 GHz is considered. The mm-WB Radio Frequency (RF) signal is obtained at each Optical Network Unit (ONU) by simultaneously using optical heterodyning photo detection between two optical carriers. The generated RF modulated signal has a frequency of 12.5 GHz. This RoF system is easy, cost-effective, resistant to laser phase noise and also reduces maintenance needs, in principle. A revision of related RoF network proposals and experiments is also included. A number of models for Passive Optical Networks (PON)/ RoF-PON that combine both innovative and existing ideas along with a number of solutions for m-trail design problem of these models are proposed. The comparison between these models uses the expected survivability function which proved that these models are liable to be implemented in the new and existing PON/ RoF-PON systems. This dissertation is followed by recommendation of possible directions for future research in this area.
262

Avaliação da estabilidade, por meio da análise da frequência de ressonância (RFA), de implantes colocados na maxila posterior variando somente o tratamento de superfície: ensaio clínico randomizado / Stability evaluation, through resonance frequency analysis (RFA), of implants placed in the posterior maxilla varying only the surface treatments: randomized clinical trial

Novellino, Marcelo Michele 03 May 2018 (has links)
Contexto: Modificações químicas da superfície dos implantes dentários com o objetivo de aumentar a molhabilidade resultam em uma osseointegração mais rápida e melhor. Objetivo: O objetivo deste estudo foi avaliar o quociente de estabilidade do implante (ISQ) (implant stability quotient) de implantes com geometria idêntica, mas com tratamentos de superfície diferentes: jateamento de areia e ataque ácido (SAE) e a mesma superfície com uma modificação química para aumento da hidrofilia, dentro das primeiras 16 semanas de cicatrização. Materiais e Método: neste estudo clínico randomizado um total de 64 implantes (32 SAE - Grupo Controle e 32 SAE modificado - Grupo Teste) com o mesmo desenho geométrico, comprimento e diâmetro (cônico e compressivo, 4,3x10 mm) foram colocados na maxila posterior de 21 pacientes parcialmente desdentados. Os valores de ISQ foram coletados no pós - cirúrgico imediato (T0), com 1 semana (T1), 2 (T2), 3 (T3), 5 ( T4), 8 (T5), 12 (T6) e 16 semanas (T7). Os resultados foram comparados por meio do ANOVA de medidas repetidas. Resultados: O grupo teste apresentou valores de ISQ mais altos que o grupo controle (ANOVA - p<0,01) a partir da 5a semana. Quando comparados os grupos em relação ao tempo necessário para se atingir o ISQ >= 70 como uma referência, houve uma diferença estatisticamente significante (p<0,01) e um Hazard Ratio de 2,24 (IC 1,62-3,11). No acompanhamento de um ano um paciente com 2 implantes abandonou a pesquisa, e estes não puderam mais ser avaliados. A taxa de sobrevida de ambos grupos foi de 100% após um ano de acompanhamento. Conclusão: O presente estudo sugere que implantes com superfície hidrofílica osseointegram mais rápido que implantes com superfície SAE convencional. O ganho de estabilidade do grupo teste foi 2,24 vezes mais rápido que do grupo controle após 5 semanas de avaliação em leitos na maxila posterior. / Background: Chemical modifications of dental implant surface, to improve the wettability, results in a faster and better osseointegration. Purpose: The aim of this study was to evaluate the implant stability quotient (ISQ) of implants with the same design, treated with two different surfaces: Sandblasted Acid-Etched (SAE) and hydrophilic SAE, within the initial 16 weeks of healing. Materials and Method: For this RCT a total of 64 implants (32 SAE - Control Group and 32 modified SAE - Test Group) with the same design, length and diameter (conical and compressive, 4.3x10 mm) were inserted in the posterior maxillae of 21 patients partially edentulous. The ISQ values were collected at the post-surgery (T0), 1-week (T1), 2-weeks (T2), 3- weeks (T3), 5-weeks (T4), 8-weeks (T5), 12-weeks (T6) and 16-weeks (T7). The statistic test was ANOVA. Results: Test group presented ISQ values higher than the Control group (ANOVA - p<0.01) from 5th week. When comparing groups regarding the amount of time required to achieve ISQ >= 70 as a reference, there was a statistically significant difference (p <0.01), and a HR (Hazard Ratio) of 2.24 (CI 1.62- 3.11). At the one-year follow up, there was a drop out of one patient and two implants were no longer evaluated. Survival rate for both groups was of 100% after one year of follow up. Conclusion: The current study suggests that implants with hydrophilic surface (modified SAE) integrates faster than implants with SAE surface. Stability gain of the tested group was 2.24 times faster than the control group after five weeks of evaluation at the posterior region of maxillae.
263

Validação do teste de trilhas - B (trail making test - B) para uso em pacientes brasileiros com câncer em cuidados paliativos / Validation of Trail Making Test B for Brazilian patients with cancer in palliative care

Santos, Juliano dos 12 July 2011 (has links)
Introdução: Prejuízos na atenção, concentração e execução de tarefas, entre outras funções cognitivas, parecem ser frequentes em doentes com câncer e em cuidados paliativos e podem comprometer o cotidiano desses pacientes. No entanto, há poucos estudos sobre o tema e desconhecem-se testes validados para essa população no Brasil. Objetivo: Validar o Teste de Trilhas B (TT-B) para uso em pacientes com câncer em cuidados paliativos. Método: Trata-se de estudo metodológico, de validação de instrumento, que envolveu pacientes (n=94) em tratamento paliativo no Ambulatório de Quimioterapia do Instituto do Câncer do Estado de São Paulo e seus acompanhantes (n=39). Os avaliados realizaram o TT-B e responderam dados sócio-demográficos, sobre a presença e intensidade de dor, de fadiga, sobre a qualidade do sono, ansiedade e depressão, em dois momentos, com intervalo máximo de sete dias. Os doentes também foram caracterizados quanto à doença e tratamento. As validades convergente e divergente foram testadas pela correlação entre o desempenho no TT-B, mensurado pelo tempo para a realização do teste e o número de erros cometidos, com a intensidade da dor, da fadiga, da ansiedade, da depressão e do repouso atribuído ao sono da noite anterior às avaliações. A validade discriminante foi testada pela comparação do TT-B entre doentes e sadios. A estabilidade do TT-B, em doentes e sadios, foi avaliada por meio de teste e reteste. Resultados: Os doentes tinham câncer colo-retal (47,8%), câncer de mama (15,9%), a totalidade apresentava metástase, foram homens (52,1%), com idade média de 53 anos. Para os doentes, o tempo médio de realização do TT-B foi de 147,5 segundos na primeira e 132 segundos na segunda avaliação e o número de erros médio foi de 1 na primeira e 0,8 na segunda avaliação. Para os acompanhantes o tempo de realização do TT-B foi de 127,3 e 110,7 segundos na primeira e segunda avaliação respectivamente e o número de erros foi 0,9 na primeira e 0,6 na segunda avaliação. O instrumento discriminou doentes de sadios em relação ao tempo utilizado para a realização do teste na primeira (p=0,014) e na segunda (p=0,035) avaliação, indicando melhor desempenho para os sadios, mas não em relação ao número de erros. O teste foi estável entre os sadios nas duas avaliações, tanto em relação ao tempo (p=0,071) quanto em relação ao número de erros (p=0,352) e entre os doentes o instrumento foi estável apenas em relação ao número de erros (p=0,913). O TT-B não demonstrou correlações significativas com dor, fadiga, depressão, ansiedade e descanso, o que causou estranheza. Conclusão: O TT-B está em processo de validação. Mostrou-se capaz de discriminar doentes de sadios e foi estável entre os saudáveis. Recomenda-se a continuidade de estudos com amostras maiores e a utilização do TT-B em paralelo a outro instrumento que avalie a função executiva. / Introduction: Impairments in attention, concentration and execution of tasks, among other cognitive functions, seem to be frequent in patients with cancer in palliative care and they can affect patients daily life. However, there are few studies about the theme and to our knowledge there are no validated tests for this population in Brazil. Objective: To validate Trial Making TestB (TMT-B) for assessment of patients with cancer in palliative care. Methods: Methodological study to validate an instrument that involved patients (n=94) in palliative treatment at the Clinic of Chemotherapy of the Instituto do Câncer do Estado de São Paulo and their healthy accompanying person (n=39). Patients were tested on TMT-B and answered demographic data, questions about the presence of pain and intensity, fatigue, quality of sleep, anxiety and depression, in two moments, with maximum interval of seven days. The patients were also characterized according to disease and treatment. The convergent and divergent validities were tested by the correlation between the performance on TMT-B, measured by the amount of time required to complete the task and the number of mistakes, and pain intensity, fatigue, anxiety, depression and the rest attributed to sleep in the previous night before assessments. The discriminate validity was tested by the comparison of TMT-B between patients and healthy accompany persons. The stability of TMT-B, in patients and healthy companions was evaluated through test and re-test. Results: The patients had colorectal cancer (47.8%), followed by breast cancer (15.9%), the totality presented metastasis, most patients were men (52.1%), mean age was 53 years. For patients, mean time required to complete TMT-B was 147.5 seconds in the first and 132 seconds in the second assessments and the mean number of mistakes was 1 in the first and 0.8 in the second assessments. For the healthy accompany person, the time required to complete TMT-B was respectively 127.3 and 110.7 seconds in the first and second assessments and the number of mistakes was 0.9 in the first and 0.6 in the second assessments. The instrument discriminated patients from healthy accompany persons regarding time required to complete the test in the first (p=0.014) and second (p=0.035) assessments, indicating better performance for the healthy ones, but not in relation to the number of mistakes. The test was stable among healthy people in the two assessments regarding time (p=0.071) and number of mistakes (p=0.352); for patients, the instrument was stable only in relation to the number of mistakes (p=0.913). TMT-B did not demonstrate significant correlations with pain, fatigue, depression, anxiety and rest. Conclusion: TMT-B is in validation process. It was able to discriminate between patients and healthy accompany persons and was stable for the healthy ones. Further studies are recommended with larger samples as well as the use of TMT-B in parallel to other instrument that evaluates the executive function.
264

Fatores de degradação ambiental e elementos construtivos na avaliação e monitoramento de escadas no percurso de trilhas no parque estadual turístico do Alto Ribeira / Environmental degradation factors and constructive elements in the assessment and monitoring of stairs in the course of Alto Ribeira Touristic State Park pathways

Kabashima, Yukie 14 June 2011 (has links)
A avaliação e monitoramento de trilhas vêm sendo implantados nos últimos anos nas unidades de conservação brasileiras. No entanto, as escadas, como parte do caminho percorrido pelos usuários não são consideradas. Este tipo de infraestrutura ocorre com maior frequência em terrenos acidentados como onde se encontra o Parque Estadual Turístico do Alto Ribeira (PETAR), local selecionado para o desenvolvimento desta pesquisa. O presente trabalho teve como objetivos descrever e avaliar os fatores que colaboram na degradação dos degraus feitos com troncos de madeira; verificar se essas escadas podem ser avaliadas da mesma forma que o restante da trilha; e com base nos resultados obtidos propor um protocolo preliminar de avaliação e monitoramento deste tipo de estrutura nas trilhas em áreas naturais. Com base nas informações obtidas, procurou-se fornecer subsídio para o manejo de trilhas em áreas naturais, especialmente em unidades de conservação. A coleta de dados detalhados das escadas foi feita em julho de 2010. A análise das informações coletadas em campo mostra que: a) a extensão do segmento de escada influencia na quantidade de afundamentos nos pisos dos degraus; b) a declividade não interfere na intensidade de erosão e empoçamento; c) a ergonomia, apesar de não apresentar correlação com os impactos negativos ao meio, pode interferir na qualidade de experiência e segurança do usuário; d) a insolação interfere na quantidade de poças; e) a presença de cobertura de copas pode auxiliar na minimização de impactos de chuva; f) há a necessidade de melhor capacitação daqueles que trabalham no manejo de trilhas; e g) as escadas necessitam de avaliação e monitoramento diferenciadas do restante da trilha. Para o PETAR, foram selecionados para o protocolo preliminar de avaliação e monitoramento de escadas feitas com troncos de madeira os seguintes indicadores: 1) existência de raízes expostas; 2) rugosidade ou irregularidade do piso que dificulte o caminhamento; 3) presença de trilhas não oficiais e seu motivo; 4) largura do degrau; 5) profundidade do degrau; 6) altura do degrau; 7) distância do segmento de degraus; 8) pontos com maior afundamento no piso do degrau; 9) estruturas de drenagem bloqueadas por queda de vegetação e sedimentação; 10) presença de estrutura de drenagem no topo dos segmentos de escadas; e 11) erosão na base dos degraus. / The trail evaluation and monitoring have been undertaken in detail throughout Brazilian protected areas. However, stairs, as a component of the pathway used by the visitors, are not taken into account. This kind of infrastructure is present more frequently in steeper terrains as where Alto Ribeira Touristic State Park (PETAR) is located, the selected area for this research. The goals of this research were to describe and evaluate the elements that contribute to the wood stair degradation; verify if these stairs can be evaluated in the same way as the rest of the trail; and based on the results suggest a preliminary protocol to evaluate and monitor this kind of structure in natural area trails. Based on the results found, the objective is to contribute to the trail management in natural areas, especially in protected areas. The detailed data on the stairs was collected in July 2010. The analysis of the data demonstrates: a) the depression quantity on the tread was affected by the length of the stair section; b) the intensity of erosion and puddle were not affected by the tread grade; c) despite the fact that ergonomics didnt show correlation with the negative impacts, it can interfere in the quality of user experience and safety; d) the solar exposure influences the quantity of puddles; e) the presence of canopy cover can minimize raindrop impact; f) better training is needed for the staff involved in trail management; and g) the stairs need differentiated evaluation and monitoring from the rest of the trail. The following indicators were selected for the preliminary protocol to evaluate and monitor the PETAR wood stairs: 1) presence of exposed tree roots; 2) tread roughness that makes it difficult to walk; 3) presence of social trails and its causes; 4) step width; 5) step depth; 6) step height; 7) length of the stair section; 8) location of the deeper depression spots in the steps; 9) drainage structures obstructed by fallen vegetation or sedimentation; 10) presence of drainage structure at the top of the stair section; and 11) erosion in the bottom of the steps.
265

Průřezové téma "Les" a lesní pedagogika jako jedna z možností jeho realizace / Cross-curricular theme "Forest" and forest pedagogy as one of the possibilities of its realization

Kozák, Jaromír January 2012 (has links)
Cross-curricular themes are important formative elements of education. A forest ecosystem is an environment with great importance and potential, and knowledge of forest ecosystem, processes taking place in it and human activities associated with it can be included in many educational areas. By combining these two phenomena we gain cross- curricular theme "Forest". A possible instrument for realization this theme is the forest pedagogy. In the theoretical part of the work is the term cross-curricular theme delineated and defined in general and also specifically on the example of cross-curricular theme "Forest". About the forest ecosystem are given knowledge that contribute to spreading the results of forestry research and to modernization of teaching about the forest ecosystem at elementary and secondary schools. The forest pedagogy is introduced as an instrument that can significantly contributes to deepen the learning points about "Forest" and its presentation as cross-curricular theme. In the practical part of this work are the results of a survey that contributed to the findings of the current state of implementation of cross-curricular theme "Forest" in teaching in elementary and secondary schools. They turned out, what is the awareness of forest pedagogy among teachers nowadays, and what...
266

Influência da umidade relativa no desempenho da tarefa de busca de água em formigas-cortadeiras da espécie Atta sexdens rubropilosa (Forel, 1908). / Influence of relative humidity on the task of water collection in the leaf-cutting ant Atta sexdens rubropilosa (Forel, 1908).

Estrella, Nathalia Sena Polydoro 18 May 2018 (has links)
Fatores ambientais abióticos, como o clima, possuem um efeito profundo sobre a biologia dos organismos e sua distribuição em diferentes habitats. Os insetos, sendo o grupo animal mais abundante do planeta, tem papel importante no entendimento de como as variações climáticas afetam a vida na Terra. Neste estudo, utilizamos as formigas-cortadeiras, da espécie Atta sexdens rubropilosa,, para tratar da importância da umidade na escolha de trilhas de forrageio. As colônias utilizadas foram separadas em dois grupos: um grupo controle, mantido em condições normais de alimentação, e um grupo experimental, alimentado com substrato seco, provocando desidratação da colônia. Os dois grupos foram submetidos a um teste de escolha de trilhas para coleta de água: uma das trilhas foi mantida úmida e a outra mantida seca. As formigas que passaram pelas trilhas, por 24 horas, foram contadas e medidas (estas últimas selecionadas aleatoriamente nas trilhas). Após análise de vídeos, os resultados mostraram que, para o fluxo, houve diferença significativa, tanto entre os grupos quanto entre as trilhas. O fluxo foi sempre maior no grupo experimental, em relação ao controle, e maior na trilha úmida que na trilha seca - sendo assimetricamente maior no grupo experimental. Este resultado demonstra que o estado fisiológico da colônia e das operárias influencia fortemente a saída de forrageadoras e a coleta de água. Além disso, mostra que a escolha da trilha foi influenciada pelo ambiente, com grande preferência das formigas pela trilha úmida. Com relação aos tamanhos, a diferença foi significativa para dois fatores: as formigas nas trilhas do grupo experimental eram, em média, menores do que as formigas do grupo controle. Há relatos de que formigas menores são especializadas em coletar água, o que explica este resultado: no grupo experimental, a dessecação impulsiona as formigas a coletar água de maneira sistemática para reidratação. No grupo experimental, as formigas eram menores na trilha seca do que as da trilha úmida, o que vai contra o esperado se levar em consideração as relações alométricas de perda evaporativa de água. É provável que esse fator esteja ligado ao engajamento na tarefa de coleta de água pelas formigas menores, que é constante nas duas trilhas, dada a necessidade da colônia. Mais estudos, no entanto, são necessários para aprimorar e aprofundar estas questões, especialmente levando em conta a dicotomia entre o comportamento individual e o coletivo / Environmental abiotic factors, such as weather, have a profound impact over the biology of organisms e their distribution on different habitats. Insects, being the most abundant animal group on the planet, play an important role to understand how climatic changes affect life on Earth. In this study, we use leafcutter ants of the species Atta sexdens rubropilosa in order to approach the importance of humidity in the choice of foraging trails. The colonies used were separated in two groups: a control group, kept under normal feeding conditions and an experimental group, fed with dry substrate, which provoked dehydration on the colony. Both groups were submitted to a test of trail choice for water collection: one of the trails was kept humid, while the other was kept dry. Ants that travelled through the trails over 24 hours were counted and measured (in the last case, randomly chosen on the trails). After video analysis, the results show that, regarding to flow, there was a significant difference between groups and between trails. Ants flow were always higher on the experimental group than on the control group, and higher on the humid trail than on the dry trail - being asymmetrically higher on the experimental group. These results show that the physiological state of the colony and the workers strongly influences the exit of foragers and the collection of water. Besides, it shows that trail choice was influenced by the environment, with ants preferring the humid trail. Regarding body size, the difference was significant for two factors: ants on the trails of the experimental group were, on average, smaller than ants from the control group. There are reports that smaller ants are specialized on water collection, which explains that difference: on the experimental group, dehydration pushes ants to collect water systematically for rehydrating. On the experimental group, ants were smaller on the dry trail than the ones on the humid trail, which goes against expected when we consider allometric relations for evaporative water loss. It is likely that this factor is connected to the smaller ant´s engagement to the water collection task, which is constant on both trails due the needs of the colony for water. More studies, however, are necessary to improve and deepen those questions, specially taking onto account the dichotomy between individual and collective behavior
267

Our Vision of Health for Future Generations: an Exploration of Proximal and Intermediary Motivations with Women of the Choctaw Nation of Oklahoma

Brown, Danica Love 12 March 2019 (has links)
Health disparities and substance misuse are increasingly prevalent, costly, and deadly in Indian Country. Although women historically held positions of influence in pre-colonial Tribal societies and shared in optimum health, their current health is relegated to some of the worst outcomes across all racial groups in the United States. Women of the Choctaw Nation of Oklahoma (CNO) have some of the highest prevalence estimates in physical inactivity and excessive drinking in the United States. Building on the Indigenous Stress Coping model of indigenous health, "Our Vision of Health for Future Generations" explores the intersection of a historical event, the Trail of Tears, and its lasting impact on the contemporary health outcomes in tribal members. This inquiry is positioned within the Yappallí Choctaw Road to Health project that explores these broader issues. This culturally-centered study explores proximal and settings-based/intermediary motivations of twenty-three women who completed the Yappallí­ project, walked the Trail of Tears, and developed a holitobit ibbak fohki "sacred giving" community health event. Analysis was conducted using the Listening Guide method, that highlighted the contrapuntal voices of embodiment, motivation, challenges, and transformation. Participants shared stories in relation to both their individual health concerns (proximal), and deep love and commitment for the health of their family, community and for future generations (intermediary). This study provides another framework for the development of indigenized research, by using in-depth interviews, haklo "listen deeply" as a form of indigenous storywork that is centering of the experiences of marginalized people, and reflexivity as anukfilli "Deep Reflection."
268

Trophic interactions on Zea spp. plants involving the herbivores Spodoptera frugiperda (J.E. Smith), Diatraea saccharalis (Fabricius) and the predator Doru luteipes Scudder / Interações tróficas em plantas Zea spp. envolvendo os herbivoros Spodoptera frugiperda (J. E. Smith), Diatrea saccharalis (Fabricius) e o predador Doru luteipes Scudder

Naranjo, Natalia Guevara 09 March 2017 (has links)
The earwigs (Dermaptera) contains mostly nocturnal insects, which are considered subsocial due to formation of aggregated family groups and maternal care. Species of Dermaptera have been shown to play an important role as generalist predators in different crop systems worldwide. Despite that, the knowledge about their behavior and insect-plant interactions remains poorly understood. The earwig Doru luteipes (Dermaptera: Forficulidae) is one of the most important generalist predators in different crops, especially in maize (Zea mays ssp. mays) by voraciously consuming eggs and larvae of Spodoptera frugiperda (Lepidoptera: Noctuidae) and Diatraea saccharalis (Lepidoptera: Crambidae), key pests in this crop. Maize is one of most produced cereals in the word. However, great losses are registered annually due to pest attacks, despite the use of pesticides. Studies have demonstrated that domesticated plants such as maize have reduced defenses against herbivores in detriment to intensely selecting for rapid growth and high yield, when compared with their wild ancestors\' species known as teosintes (Zea spp.). This thesis focuses on the study of the trophic interactions which occur in the system \'Zea plants - herbivores caterpillars - predator earwig\' and is divided in four chapters. In the Chapter 1 is present a general introduction and the thesis outline. In the Chapter 2, we studied through scent collection and multiple-choice bioassays, the communication between D. luteipes individuals which influences their predatory behavior. Our results indicate that earwigs can produce and use chemical cues by conspecifics to orientate them towards foraging resources. In the Chapter 3, we investigated the predation behavior of earwigs during photo- and scotophase and their preference for maize volatiles induced by S. frugiperda or D. saccharalis at different time intervals (early and old damage). Behavior, olfactometry bioassays and plant volatile collections were conducted. As was hypothesized, earwigs showed a predation activity only during night. Besides that, they were attracted by maize odors produced by both caterpillars and showed significant preference to early-damage odors over old-damage. Therefore, it is considered that early-damage volatiles (Green Leaf Volatiles-GLVs) could be the key compounds of D. luteipes attraction. In the last part (Chapter 4) was explored how domestication of Zea plants influences insect-plants interactions through plant defense. Experiments about food utilization by caterpillars, olfactometry bioassays and plant volatile collections were conducted. Interestingly, as in the previous chapter, we suggest that GLVs have an important role in earwig attraction. The results show that life-history of Zea plants influences plant defense and consequently the plant-insect interactions. In conclusion, our findings bring a new contribution to the knowledge about plant defenses in a tritrophic context and predatory strategies in D. luteipes, which would promote alternatives to optimize the conservation and biological control of pest by predators in the field. / As tesourinhas (Dermaptera) são em sua maioria insetos noturnos considerados sub-sociais devido ao cuidado maternal e à formação de grupos familiares agregados. Espécies de Dermaptera possuem um papel importante como predadores generalistas em diferentes culturas em todo mundo. Apesar disso, o conhecimento sobre seu comportamento e as interações inseto-planta permanecem pouco estudadas. A tesourinha Doru luteipes Scudder (Dermaptera: Forficulidae) é um dos predadores mais frequentes em diferentes culturas, especialmente no milho (Zea mays ssp. mays), devido ao voraz consumo de ovos e lagartas de Spodoptera frugiperda e Diatraea saccharalis, pragas chave nesta cultura. O milho é um dos cereais mais produzidos no mundo, embora grandes perdas sejam registradas anualmente devido ao ataque de pragas, apesar do uso de agroquímicos. Estudos recentes demostraram que plantas domesticadas tais como o milho têm reduzido suas defesas contra os herbívoros em detrimento à intensa seleção de cultivares de rápido crescimento e alta produtividade, quando comparados com seus ancestrais selvagens conhecidos como teosintos (Zea spp.). Esta tese foca no estudo das interações tróficas que ocorrem no sistema \'plantas Zea - lagartas herbívoras - tesourinhas predadoras\' e foi dividida em quatro capítulos. No Capítulo 1, apresenta-se uma introdução geral e o esboço da tese. No Capítulo 2, a partir da coleta de voláteis de adultos de D. luteipes e ensaios de múltipla escolha, foi estudada a comunicação química entre estes indivíduos que influencia o comportamento de predação. No Capítulo 3 foi investigado o comportamento de predação das tesourinhas durante a foto e escotofase, e a preferência delas pelos voláteis do milho induzidos por S. frugiperda ou D. saccharalis, em diferentes intervalos de tempo (dano recente ou dano tardio). As tesourinhas mostraram atividade predatória apenas durante a noite, e foram atraídas pelos odores do milho atacados pelas duas lagartas. O dano recente (voláteis de folhas verdes-VFVs) contêm os compostos chaves para a atração de D. luteipes. No Capítulo 4 foi explorado como a domesticação das plantas Zea influenciam as interações com insetos por meio das defesas de plantas. Assim como no capitulo anterior, os VFVs apresentaram um importante papel na atração das tesourinhas. Os resultados indicaram que a história de vida do gênero Zea influenciou as defesas das plantas e consequentemente, as interações inseto-planta. Em conclusão, o presente trabalho traz novas contribuições ao conhecimento sobre defesas de plantas num contexto tritrófico, bem como às estratégias de predação em D. luteipes, o qual pode gerar ferramentas para otimizar a conservação e controle biológico de pragas por predadores em campo.
269

Deploying Monitoring Trails for Fault Localization in All-optical Networks and Radio-over-Fiber Passive Optical Networks

Maamoun, Khaled M. 24 August 2012 (has links)
Fault localization is the process of realizing the true source of a failure from a set of collected failure notifications. Isolating failure recovery within the network optical domain is necessary to resolve alarm storm problems. The introduction of the monitoring trail (m-trail) has been proven to deliver better performance by employing monitoring resources in a form of optical trails - a monitoring framework that generalizes all the previously reported counterparts. In this dissertation, the m-trail design is explored and a focus is given to the analysis on using m-trails with established lightpaths to achieve fault localization. This process saves network resources by reducing the number of the m-trails required for fault localization and therefore the number of wavelengths used in the network. A novel approach based on Geographic Midpoint Technique, an adapted version of the Chinese Postman’s Problem (CPP) solution and an adapted version of the Traveling Salesman’s Problem (TSP) solution algorithms is introduced. The desirable features of network architectures and the enabling of innovative technologies for delivering future millimeter-waveband (mm-WB) Radio-over-Fiber (RoF) systems for wireless services integrated in a Dense Wavelength Division Multiplexing (DWDM) is proposed in this dissertation. For the conceptual illustration, a DWDM RoF system with channel spacing of 12.5 GHz is considered. The mm-WB Radio Frequency (RF) signal is obtained at each Optical Network Unit (ONU) by simultaneously using optical heterodyning photo detection between two optical carriers. The generated RF modulated signal has a frequency of 12.5 GHz. This RoF system is easy, cost-effective, resistant to laser phase noise and also reduces maintenance needs, in principle. A revision of related RoF network proposals and experiments is also included. A number of models for Passive Optical Networks (PON)/ RoF-PON that combine both innovative and existing ideas along with a number of solutions for m-trail design problem of these models are proposed. The comparison between these models uses the expected survivability function which proved that these models are liable to be implemented in the new and existing PON/ RoF-PON systems. This dissertation is followed by recommendation of possible directions for future research in this area.
270

Les cellules dendritiques plasmacytoïdes dans le cancer à travers le rôle de TRAIL

Blum, Ariane 14 May 2007 (has links) (PDF)
Les cellules dendritiques plasmacytoïdes (PDC) représentent une nouvelle entité distincte de cellules dendritiques. Elles peuvent sécréter de grandes quantités d'interféron de type I après stimulation par un virus ou des produits bactériens tels que les CpG ODN grâce à leur expression sélective des Toll-like récepteurs (TLR)7 et 9.<br />Notre laboratoire a récemment développé une lignée de PDC (GEN2.2) à partir de leucémies à PDC (LPDC), qui résistent aux thérapies conventionnelles. Les GEN2.2 partagent la plupart des caractéristiques phénotypiques et fonctionnelles des PDC normales. Nous avons d'abord utilisé cette lignée comme modèle de LPDC et nous montrons qu'elles sont sensibles à l'apoptose induite par TRAIL (TNF-Related Apoptosis-Inducing Ligand) via l'expression du récepteur DR5, comme la plupart des LPDC, alors que les PDC normales ne le sont pas, ce qui permettrait la mise en place de thérapies des leucémies à PDC utilisant des agonistes de TRAIL.<br />Les PDC normales sont difficiles à isoler ou générer. Nous avons donc ensuite utilisé la lignée GEN2.2 comme modèle de PDC normales. Nous avons ainsi découvert que ces cellules, une fois activées par des ligands des TLR7 et 9, acquièrent une fonction cytotoxique via l'expression de TRAIL et peuvent tuer des cellules tumorales. Les PDC pourraient donc jouer un rôle crucial dans l'éradication des cancers après activation.<br />Enfin, nous avons cherché à préciser les mécanismes moléculaires d'induction de TRAIL dans les PDC après activation par des ligands des TLR7 et 9.<br />L'ensemble des travaux suggère que les PDC pourraient représenter une cible de choix dans le développement de nouvelles approches thérapeutiques anti-tumorales.

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