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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.
1

Worldwide occurrence of sporadic E

Smith, Ernest K. January 1957 (has links)
Thesis--Cornell University. / Without thesis statement. Bibliography: p. 273-278.
2

Generating sporadic association rules

Koh, Yun Sing, n/a January 2007 (has links)
Association rule mining is an essential part of data mining, which tries to discover associations, relationships, or correlations among sets of items. As it was initially proposed for market basket analysis, most of the previous research focuses on generating frequent patterns. This thesis focuses on finding infrequent patterns, which we call sporadic rules. They represent rare itemsets that are scattered sporadically throughout the database but with high confidence of occurring together. As sporadic rules have low support the minabssup (minimum absolute support) measure was proposed to filter out any rules with low support whose occurrence is indistinguishable from that of coincidence. There are two classes of sporadic rules: perfectly sporadic and imperfectly sporadic rules. Apriori-Inverse was then proposed for perfectly sporadic rule generation. It uses a maximum support threshold and user-defined minimum confidence threshold. This method is designed to find itemsets which consist only of items falling below a maximum support threshold. However imperfectly sporadic rules may contain items with a frequency of occurrence over the maximum support threshold. To look for these rules, variations of Apriori-Inverse, namely Fixed Threshold, Adaptive Threshold, and Hill Climbing, were proposed. However these extensions are heuristic. Thus the MIISR algorithm was proposed to find imperfectly sporadic rules using item constraints, which capture rules with a single-item consequent below the maximum support threshold. A comprehensive evaluation of sporadic rules and current interestingness measures was carried out. Our investigation suggests that current interestingness measures are not suitable for detecting sporadic rules.
3

Currarino syndrome : gene identification and mutational analysis

Ross, Alison Jane January 2001 (has links)
No description available.
4

Interrelation of ionospheric sporadic E with thunderstorms and jet streams

Damon, Thomas DeLoyd, January 1965 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1965. / eContent provider-neutral record in process. Description based on print version record. Bibliography: l. 30-32.
5

Symmetric representation of elements of sporadic groups

Harris, Elena Yavorska 01 January 2005 (has links)
Uses the techniques of symmetric presentations to manipulate elements of large sporadic groups and to represent elements of these groups in much shorter forms than their corresponding permutation or matrix representation. Undertakes to develop a nested algorithm and a computer program to manipulate elements of large sporadic groups.
6

Higher order commutators in the method of orbits

Unknown Date (has links)
Benson spaces of higher order are introduced extending the idea of N. Krugljak and M. Milman, A distance between orbits that controls commutator estimates and invertibilty of operators, Advances in Mathematics 182 (2004), 78-123. The concept of Benson shift operators is introduced and a class of spaces equipped with these operators is considered. Commutator theorems of higher order on orbit spaces generated by a single element are proved for this class. It is shown that these results apply to the complex method of interpolation and to the real method of interpolation for the case q=1. Two new characterizations are presented of the domain space of the "derivation" operator in the context of orbital methods. Comparisons to the work of others are made, especially the unifying paper of M. Cwikel, N. Kalton, M. Milman and R. Rochberg, A United Theory of Commutator Estimates for a Class of Interpolation Methods, Advances in Mathematics 169 2002, 241-312. / by Eva, Kasprikova / Thesis (Ph.D.)--Florida Atlantic University, 2009. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2009. Mode of access: World Wide Web.
7

Graphs associated with sporadic group geometries, and the semisimple elements of E8(2)

Phillips, Jamie January 2016 (has links)
This thesis studies collinearity graphs and commuting involution graphs associated with sporadic group geometries, and the conjugacy classes of semisimple elements in the exceptional Lie-type group E8(2).First we construct plane-line collinearity graphs for the sporadic simple groups and their associated minimal and maximal 2-local parabolic geometries. For such a group and geometry, the plane-line collinearity graph takes all planes of the geometry as its vertices and joins two vertices with an edge if their planes are collinear in the geometry. We construct these graphs for the groups M23, J4, Fi22, Fi23, He, Co3 and Co2. Additionally we construct a variety of collinearity graphs associated with the minimal 2-local geometries of McL.A second short study looks at the commuting involution graphs associated with the Baby Monster sporadic group. These are graphs which take a conjugacy class of involutions as its vertex set and joins two vertices with an edge if they commute. We detail information relating to two such graphs. Finally, we study the conjugacy classes of semisimple elements in the exceptional group E8(2). This study is a joint work with Ali Aubad, John Ballantyne, Alexander McGaw, Peter Neuhaus, Peter Rowley and David Ward in which we determine the structure of centralisers for all such elements including information such as fixed-space dimensions and powering up maps. The ultimate aim is to determine all maximal subgroups of E8(2). This is a lengthy ongoing project and this study forms part of that effort.
8

Aperiodic Job Handling in Cache-Based Real-Time Systems

Motakpalli, Sankalpanand 01 December 2017 (has links)
Real-time systems require a-priori temporal guarantees. While most of the normal operation in such a system is modeled using time-driven, hard-deadline sporadic tasks, event-driven behavior is modeled using aperiodic jobs with soft or no deadlines. To provide good Quality-of- Service for aperiodic jobs in the presence of sporadic tasks, aperiodic servers were introduced. Aperiodic servers act as a sporadic task and reserve a quota periodically to serve aperiodic jobs. The use of aperiodic servers in systems with caches is unsafe because aperiodic servers do not take into account, the indirect cache-related preemption delays that the execution of aperiodic jobs might impose on the lower-priority sporadic tasks, thus jeopardizing their safety. To solve this problem, we propose an enhancement to the aperiodic server that we call a Cache Delay Server. Here, each lower-priority sporadic task is assigned a delay quota to accommodate the cache-related preemption delay imposed by the execution of aperiodic jobs. Aperiodic jobs are allowed to execute at their assigned server priority only when all the active lower-priority sporadic tasks have a sufficient delay quota to accommodate it. Simulation results demonstrate that a Cache Delay Server ensures the safety of sporadic tasks while providing acceptable Quality-of-Service for aperiodic jobs. We propose a Integer Linear Program based approach to calculate delay quotas for sporadic tasks within a task set where Cache Delay Servers have been pre-assigned. We then propose algorithms to determine Cache Delay Server characteristics for a given sporadic task set. Finally, we extend the Cache Delay Server concept to multi-core architectures and propose approaches to schedule aperiodic jobs on appropriate Cache Delay Servers. Simulation results demonstrate the effectiveness of all our proposed algorithms in improving aperiodic job response times while maintaining the safety of sporadic task execution.
9

Caracterização imunogenética de variantes dos genes CCR2, CCR5 e HLA-G como potenciais alvos para diagnóstico, prognóstico e tratamento do câncer de mama feminino esporádico e familial

Giongo, Cíntia de Oliveira January 2012 (has links)
O câncer de mama é a neoplasia mais comum entre as mulheres. Sua etiologia é complexa, onde tanto fatores ambientais como genéticos podem contribuir para o desenvolvimento tumoral. Estima-se que 5 a 10% dos casos de carcinomas de mama sejam representados pelos carcinomas de mama familial e 90 a 95% sejam representados pelos carcinomas de mama esporádicos. Independente da etiologia, um dos principais agravantes é consequência da habilidade das células tumorais metastizar. Mutações podem levar a mudança ou perda de expressão de diferentes genes e isto possibilita que as células adquiram particularidades genéticas e fenotípicas que contribuem para a progressão do tumor através da aquisição de vantagens que medeiam a sua sobrevivência. Dentre estas vantagens adquiridas está a capacidade das células tumorais de escaparem da destruição pelas células imunológicas ou, até mesmo, utilizarem estas células a seu favor, na promoção de um microambiente tumoral inflamatório que pode auxiliar o desenvolvimento da angiogênese que posteriormente facilitará a metástase. As características dos carcinomas de mama são as principais ferramentas para avaliação do diagnóstico e prognóstico da doença. Portanto, o objetivo de nosso trabalho foi a análise de quatro variantes polimórficas de genes que codificam importantes moléculas do sistema imunológico, duas relacionadas aos genes que codificam os receptores de quimiocinas, CCR2 e CCR5, e duas relacionadas ao gene HLA-G em 188 mulheres com carcinoma de mama (105 com câncer de mama familial e 83 com câncer de mama esporádico) e em 151 mulheres sem carcinoma e sem história familiar de câncer (grupo controle), como possíveis marcadores de diagnóstico e prognóstico do carcinoma de mama. Para a análise da variante do CCR2, denominada CCR264I, e para a análise de uma das variantes que codifica a molécula de HLA-G, denominada +3142, utilizou-se a técnica PCR-RFLP. Para a análise da variante do gene CCR5, denominada CCR5delta32 e para a análise da outra variante do HLA-G, caracterizada pela inserção de 14pb na região 3’UTR do gene, utilizou-se a técnica PCR. As frequências alélicas, genotípicas e haplotípicas foram estimadas e comparadas entre os grupos de mulheres, usando o Teste Qui-Quadrado ou o Teste Exato de Fisher e, posteriormente, foram relacionadas a fatores de diagnóstico e prognóstico. Observou-se maiores frequências dos alelos selvagens do CCR2, Val (p=0,040, OR 0,61, IC 95% = 0,38 – 0,98) e do CCR5, Wt (p=0,032, OR 0,46, IC 95% = 0,23 – 0,94) e maior frequência do haplótipo duplo selvagem Wt/Val destas mesmas variantes gênicas dos genes CCR2 e CCR5, nas mulheres do grupo controle (p=0,030) em relação às mulheres com câncer de mama familial. Quando as variantes foram avaliadas em conjunto com os parâmetros clínicos, observou-se que as mulheres com carcinoma de mama esporádico apresentavam a doença em idade mais elevada (57,29 ± 8,457 anos e 44,23 ± 12,092 anos para mulheres com câncer de mama esporádico e familial, respectivamente, p < 0.001) e de forma mais agressiva, com maior frequência dos carcinomas invasores (p = 0,001) que as mulheres com carcinoma de mama familial. Além disso, as variantes de inserção/deleção de 14 pb do HLA-G e CCR264I, mostraram relação positiva com a agressividade tumoral nestas mulheres (p = 0,039 e p = 0,005). Nossos dados sugerem que os carcinomas invasores possam estar relacionados a uma maior infiltração de células imunológicas e com o aumento da inflamação no microambiente tumoral, mediados pelo receptor CCR2 e pela molécula HLA-G, respectivamente. / Breast cancer is the most common cancer among women. Its etiology is complex, where genetic, environmental and endocrine factors contribute to tumor development. It is estimated that 5 to 10% of the breast cancers are represented by familial breast cancers and 90 to 95% are represented by sporadic breast cancers. Independent of the etiology, the major aggravating consequence is the ability of tumor cells to metastasize. Mutations can lead to a change or loss of expression a different genes and this allows the appearance of genetic and phenotypic features which contribute to tumor progression. Among these features is the ability of tumor cells to evade from the immune cells or even use immune cells in the promotion of a inflammatory microenvironment promotion which may help angiogenesis and, later, metastasis. The aim of our study was to evaluate four important polymorphic variants of genes which encode important immune system molecules, two related genes encoding chemokine receptors, CCR2 and CCR5, and two related to HLA-G gene in 188 women with breast cancer (105 women with familial breast cancer and 83 with sporadic breast cancer) and 151 women without cancer and family history of cancer (control group), such as potential markers for diagnosis and prognosis of breast cancer. CCR2 polymorphism, CCR264I, and one HLA-G polymorphism, +3142, were genotyped by PCR-RFLP. CCR5delta32 and 14pb HLA-G polymorphism were genotyped by PCR. Allelic, genotypic and haplotypic frequencies were estimated and compared between the groups using the Chi-square test or Fisher's exact test and subsequently were associated to diagnostic and prognostic factors. We observed a higher allelic frequency of the CCR2 wild type allele, Val (p = 0.040, OR 0.61, 95% CI = 0.38 - 0.98) e CCR5 wild type allele, Wt (p = 0.032, OR 0.46, CI 95% = 0.23 - 0.94) and higher haplotype frequency of the double wild type variants (Wt/Val) of these same genes (CCR2 and CCR5) in women in the control group (p = 0.030) compared to women with familial breast cancer. All polymorphisms were evaluated together with the clinical parameters and it was observed that women with breast cancer showed sporadic cancer latter (57.29 ± 8.457 years and 44.23 ± 12.092 years for women with sporadic breast cancer and familial breast cancer, respectively, p < 0.001) and more invasiveness (p = 0.001) as compared to women with familial breast cancer. Moreover, the HLA-G 14pb and CCR264I polymorphism, showed a positive association with tumor aggressiveness in women with sporadic breast cancer (p = 0.039 and p = 0.005, respectively). Our data suggest that invasive cancers may be associated with increased immune cells infiltration and inflammation in the tumor microenvironment mediated by both CCR2 receptor and HLA-G molecule.
10

Caracterização imunogenética de variantes dos genes CCR2, CCR5 e HLA-G como potenciais alvos para diagnóstico, prognóstico e tratamento do câncer de mama feminino esporádico e familial

Giongo, Cíntia de Oliveira January 2012 (has links)
O câncer de mama é a neoplasia mais comum entre as mulheres. Sua etiologia é complexa, onde tanto fatores ambientais como genéticos podem contribuir para o desenvolvimento tumoral. Estima-se que 5 a 10% dos casos de carcinomas de mama sejam representados pelos carcinomas de mama familial e 90 a 95% sejam representados pelos carcinomas de mama esporádicos. Independente da etiologia, um dos principais agravantes é consequência da habilidade das células tumorais metastizar. Mutações podem levar a mudança ou perda de expressão de diferentes genes e isto possibilita que as células adquiram particularidades genéticas e fenotípicas que contribuem para a progressão do tumor através da aquisição de vantagens que medeiam a sua sobrevivência. Dentre estas vantagens adquiridas está a capacidade das células tumorais de escaparem da destruição pelas células imunológicas ou, até mesmo, utilizarem estas células a seu favor, na promoção de um microambiente tumoral inflamatório que pode auxiliar o desenvolvimento da angiogênese que posteriormente facilitará a metástase. As características dos carcinomas de mama são as principais ferramentas para avaliação do diagnóstico e prognóstico da doença. Portanto, o objetivo de nosso trabalho foi a análise de quatro variantes polimórficas de genes que codificam importantes moléculas do sistema imunológico, duas relacionadas aos genes que codificam os receptores de quimiocinas, CCR2 e CCR5, e duas relacionadas ao gene HLA-G em 188 mulheres com carcinoma de mama (105 com câncer de mama familial e 83 com câncer de mama esporádico) e em 151 mulheres sem carcinoma e sem história familiar de câncer (grupo controle), como possíveis marcadores de diagnóstico e prognóstico do carcinoma de mama. Para a análise da variante do CCR2, denominada CCR264I, e para a análise de uma das variantes que codifica a molécula de HLA-G, denominada +3142, utilizou-se a técnica PCR-RFLP. Para a análise da variante do gene CCR5, denominada CCR5delta32 e para a análise da outra variante do HLA-G, caracterizada pela inserção de 14pb na região 3’UTR do gene, utilizou-se a técnica PCR. As frequências alélicas, genotípicas e haplotípicas foram estimadas e comparadas entre os grupos de mulheres, usando o Teste Qui-Quadrado ou o Teste Exato de Fisher e, posteriormente, foram relacionadas a fatores de diagnóstico e prognóstico. Observou-se maiores frequências dos alelos selvagens do CCR2, Val (p=0,040, OR 0,61, IC 95% = 0,38 – 0,98) e do CCR5, Wt (p=0,032, OR 0,46, IC 95% = 0,23 – 0,94) e maior frequência do haplótipo duplo selvagem Wt/Val destas mesmas variantes gênicas dos genes CCR2 e CCR5, nas mulheres do grupo controle (p=0,030) em relação às mulheres com câncer de mama familial. Quando as variantes foram avaliadas em conjunto com os parâmetros clínicos, observou-se que as mulheres com carcinoma de mama esporádico apresentavam a doença em idade mais elevada (57,29 ± 8,457 anos e 44,23 ± 12,092 anos para mulheres com câncer de mama esporádico e familial, respectivamente, p < 0.001) e de forma mais agressiva, com maior frequência dos carcinomas invasores (p = 0,001) que as mulheres com carcinoma de mama familial. Além disso, as variantes de inserção/deleção de 14 pb do HLA-G e CCR264I, mostraram relação positiva com a agressividade tumoral nestas mulheres (p = 0,039 e p = 0,005). Nossos dados sugerem que os carcinomas invasores possam estar relacionados a uma maior infiltração de células imunológicas e com o aumento da inflamação no microambiente tumoral, mediados pelo receptor CCR2 e pela molécula HLA-G, respectivamente. / Breast cancer is the most common cancer among women. Its etiology is complex, where genetic, environmental and endocrine factors contribute to tumor development. It is estimated that 5 to 10% of the breast cancers are represented by familial breast cancers and 90 to 95% are represented by sporadic breast cancers. Independent of the etiology, the major aggravating consequence is the ability of tumor cells to metastasize. Mutations can lead to a change or loss of expression a different genes and this allows the appearance of genetic and phenotypic features which contribute to tumor progression. Among these features is the ability of tumor cells to evade from the immune cells or even use immune cells in the promotion of a inflammatory microenvironment promotion which may help angiogenesis and, later, metastasis. The aim of our study was to evaluate four important polymorphic variants of genes which encode important immune system molecules, two related genes encoding chemokine receptors, CCR2 and CCR5, and two related to HLA-G gene in 188 women with breast cancer (105 women with familial breast cancer and 83 with sporadic breast cancer) and 151 women without cancer and family history of cancer (control group), such as potential markers for diagnosis and prognosis of breast cancer. CCR2 polymorphism, CCR264I, and one HLA-G polymorphism, +3142, were genotyped by PCR-RFLP. CCR5delta32 and 14pb HLA-G polymorphism were genotyped by PCR. Allelic, genotypic and haplotypic frequencies were estimated and compared between the groups using the Chi-square test or Fisher's exact test and subsequently were associated to diagnostic and prognostic factors. We observed a higher allelic frequency of the CCR2 wild type allele, Val (p = 0.040, OR 0.61, 95% CI = 0.38 - 0.98) e CCR5 wild type allele, Wt (p = 0.032, OR 0.46, CI 95% = 0.23 - 0.94) and higher haplotype frequency of the double wild type variants (Wt/Val) of these same genes (CCR2 and CCR5) in women in the control group (p = 0.030) compared to women with familial breast cancer. All polymorphisms were evaluated together with the clinical parameters and it was observed that women with breast cancer showed sporadic cancer latter (57.29 ± 8.457 years and 44.23 ± 12.092 years for women with sporadic breast cancer and familial breast cancer, respectively, p < 0.001) and more invasiveness (p = 0.001) as compared to women with familial breast cancer. Moreover, the HLA-G 14pb and CCR264I polymorphism, showed a positive association with tumor aggressiveness in women with sporadic breast cancer (p = 0.039 and p = 0.005, respectively). Our data suggest that invasive cancers may be associated with increased immune cells infiltration and inflammation in the tumor microenvironment mediated by both CCR2 receptor and HLA-G molecule.

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