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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.
81

Likelihood-based procedures for obtaining confidence intervals of disease Loci with general pedigree data

Wan, Shuyan 30 November 2006 (has links)
No description available.
82

Design of User-Weight-based Exercise Machines

Coombs, Dana Joseph 07 February 1997 (has links)
This thesis describes the process of designing exercise machines that raise the weight of the user as the primary source of resistance. Most strength training machines use weight stacks or springs as the source of resistance. While such machines are highly evolved and provide an excellent workout, they typically have a number of disadvantages including high cost, and large size and weight. A user weight-based exercise design will reduce the cost, size, and weight of the machine. The design process considers some important issues. Parallelogram linkages are implemented to provide non-rotary motion without the disadvantage of linear bearings. The user input is located with respect to the user providing correct relative motion for the exercise. The design also considers proper resistance curves during the design process. Specific examples are given for each step of the design process. These examples include the evolution of ideas and the creation and use of kinematic and automatic tools. / Master of Science
83

Improving case ascertainment of congenital anomalies: findings from a prospective birth cohort with detailed primary care linkage

Bishop, C., Small, Neil A., Mason, D., Corry, P., Wright, J., Parslow, Roger C., Bittles, A.H., Sheridan, E. 12 November 2017 (has links)
Yes / Congenital anomalies (CAs) are a common cause of infant death and disability. We linked children from a large birth cohort to a routine primary care database to detect CA diagnoses from birth to age 5 years. There could be evidence of underreporting by CA registries as they estimate that only 2% of CA registrations occur after age 1 year. Methods CA cases were identified by linking children from a prospective birth cohort to primary care records. CAs were classified according to the European Surveillance of CA guidelines. We calculated rates of CAs by using a bodily system group for children aged 0 to <5 years, together with risk ratios (RRs) with 95% CIs for maternal risk factors. Results Routinely collected primary care data increased the ascertainment of children with CAs from 432.9 per 10 000 live births under 1 year to 620.6 per 10 000 live births under 5 years. Consanguinity was a risk factor for Pakistani mothers (multivariable RR 1.87, 95% CI 1.46 to 2.83), and maternal age >34 years was a risk factor for mothers of other ethnicities (multivariable RR 2.19, 95% CI 1.36 to 3.54). Education was associated with a lower risk (multivariable RR 0.78, 95% CI 0.62 to 0.98). Conclusion 98% of UK CA registrations relate to diagnoses made in the first year of life. Our data suggest that this leads to incomplete case ascertainment with a further 30% identified after age 1 year in our study. Risk factors for CAs identified up to age 1 year persist up to 5 years. National registries should consider using routine data linkage to provide more complete case ascertainment after infancy. / Collaboration for Leadership in Applied Health Research and Care Yorkshire and Humber programme ‘Healthy Children Healthy Families Theme’ (IS-CLA-0113–10020).
84

Operadores de recombinação por decomposição para otimização pseudo-booleana / Operators of recombination by decomposition for pseudo-Boolean optimization

Oliveira Filho, Diogenes Laertius Silva de 24 January 2019 (has links)
Utiliza-se recombinação de soluções em diversas estratégias de otimização, principalmente aquelas relacionadas a meta-heurísticas populacionais. Operadores de recombinação por decomposição particionam as variáveis de decisão do problema de modo a permitir a decomposição da função de avaliação. Assim, encontra-se, com custo computacional proporcional ao custo de se avaliar uma solução do problema, a melhor solução entre um número de soluções descendentes que cresce exponencialmente com o número de partições encontradas. Recombinação por decomposição foi até aqui utilizada apenas em problemas em que as informações sobre o relacionamento entre as variáveis de decisão são conhecidas a priori. O objetivo principal desta pesquisa de mestrado foi o desenvolvimento de um novo operador de recombinação por decomposição para todos os problemas de otimização pseudo-Booleana. Para isso, foi necessário estimar as ligações entre as variáveis de decisão por meio de procedimentos utilizados em algoritmos de estimação de distribuição e avaliar as partições encontradas pelo novo operador de recombinação. Os resultados encontrados demonstram que o novo operador desenvolvido obteve resultados relevantes para os problemas abordados em relação a geração de novas soluções candidatas por recombinação, em comparação aos demais operadores de recombinação utilizados / The recombination of solutions is important for most of the population meta- heuristics. Recombination by decomposition partitions the decision variables of the problem in order to allow the decomposition of the evaluation function. In this way, it allows to find, with computational cost proportional to the cost of evaluating one solution of the problem, the best solution among a number of offspring solutions that grows exponentially with the number of partitions found by the recombination operator. Recombination by decomposition has been so far used only in problems where the information about the linkage between the decision variables is known. The main objective of this project was the development of new operators of recombination by decomposition for all pseudo-Boolean optimization problems. For this purpose, was necessary to estimate the linkage between the decision variables by using procedures generally employed in estimation of distribution algorithms. Our results show that the new recombination operator obtained significant results for the problems chosen relate to the generation of new solutions by recombination, in comparison to the other recombination operators used
85

Ascertainment in two-phase sampling designs for segregation and linkage analysis /

Zhu, Guohua. January 2005 (has links)
Thesis (Ph. D.)--Case Western Reserve University, 2005. / [School of Medicine] Department of Epidemiology and Biostatistics. Includes bibliographical references. Available online via OhioLINK's ETD Center.
86

Subnotificação da comorbidade Tuberculose e Aids: uma aplicação do método de linkage.

Carvalho, Carolina Novaes January 2007 (has links)
p. 1-71 / Submitted by Santiago Fabio (fabio.ssantiago@hotmail.com) on 2013-04-11T19:25:20Z No. of bitstreams: 1 Dissertacao Carolina Carvalho MP.pdf: 827108 bytes, checksum: 8070a2b199b6cd79e684b870ff01497c (MD5) / Approved for entry into archive by Maria Creuza Silva(mariakreuza@yahoo.com.br) on 2013-04-11T19:28:07Z (GMT) No. of bitstreams: 1 Dissertacao Carolina Carvalho MP.pdf: 827108 bytes, checksum: 8070a2b199b6cd79e684b870ff01497c (MD5) / Made available in DSpace on 2013-04-11T19:28:07Z (GMT). No. of bitstreams: 1 Dissertacao Carolina Carvalho MP.pdf: 827108 bytes, checksum: 8070a2b199b6cd79e684b870ff01497c (MD5) Previous issue date: 2007 / A subnotificação da comorbidade tuberculose e Aids resulta no desconhecimento da dimensão da associação entre essas doenças. O conhecimento do status HIV e da presença de Aids dos pacientes com tuberculose é essencial para o ótimo manejo do paciente. No Brasil, a vigilância dos casos de tuberculose e Aids é realizada principalmente por meio do Sistema de Informação de Agravos de Notificação (Sinan). O pareamento dos bancos de dados informatizados desses agravos pode auxiliar na identificação da subnotifcação da comorbidade TB-Aids. Objetivo: Avaliar a subnotificação da comorbidade TB-Aids no Sinan TB, no Brasil, no período de 2000 a 2005. Metodologia: Estudo descritivo exploratório utilizando os registros de casos notificados no banco do Sinan TB e banco nacional da Aids. Foram considerados casos de comorbidade TB-Aids subnotificados no Sinan TB, os registros sem informação de presença desse agravo e que foram pareados a registros da Aids que possuíssem ano de diagnóstico de Aids igual ou anterior ao ano de notificação da TB, assim como os registros de um mesmo paciente cujos registros anteriores possuíssem essa informação. Os registros de TB que possuíam informação de presença de Aids em uma variável específica foram considerados casos de comorbidade TB-Aids reconhecidos. Resultados: A subnotificação da comorbidade TB-Aids identificada no Sinan TB foi de 17,7%. Essa porcentagem variou bastante entre estados. A incorporação dos registros subnotificados aos previamente reconhecidos elevou a proporção da comorbidade TB-Aids no Brasil de 6,9% para 8,4% no período analisado. Conclusões: A evidência de subnotificação da comorbidade TB-Aids no Brasil deve deflagrar modificações no sistema de vigilância desses agravos de modo a permitir que os programas nacionais disponham dessa informação. / Salvador
87

Design of structural mechanisms

Chen, Yan January 2003 (has links)
In this dissertation, we explore the possibilities of systematically constructing large structural mechanisms using existing spatial overconstrained linkages with only revolute joints as basic elements. The first part of the dissertation is devoted to structural mechanisms (networks) based on the Bennett linkage, a well-known spatial 4R linkage. This special linkage has been used as the basic element. A particular layout of the structures has been identified allowing unlimited extension of the network by repeating elements. As a result, a family of structural mechanisms has been found which form single-layer structural mechanisms. In general, these structures deploy into profiles of cylindrical surface. Meanwhile, two special cases of the single-layer structures have been extended to form multi-layer structures. In addition, according to the mathematical derivation, the problem of connecting two similar Bennett linkages into a mobile structure, which other researchers were unable to solve, has also been solved. A study into the existence of alternative forms of the Bennett linkage has also been done. The condition for the alternative forms to achieve the compact folding and maximum expansion has been derived. This work has resulted in the creation of the most effective deployable element based on the Bennett linkage. A simple method to build the Bennett linkage in its alternative form has been introduced and verified. The corresponding networks have been obtained following the similar layout of the original Bennett linkage. The second effort has been made to construct large overconstrained structural mechanisms using hybrid Bricard linkages as basic elements. The hybrid Bricard linkage is a special case of the Bricard linkage, which is overconstrained and with a single degree of mobility. Starting with the derivation of the compatibility condition and the study of its deployment behaviour, it has been found that for some particular twists, the hybrid Bricard linkage can be folded completely into a bundle and deployed to a flat triangular profile. Based on this linkage, a network of hybrid Bricard linkages has been produced. Furthermore, in-depth research into the deployment characteristics, including kinematic bifurcation and the alternative forms of the hybrid Bricard linkage, has also been conducted. The final part of the dissertation is a study into tiling techniques in order to develop a systematic approach for determining the layout of mobile assemblies. A general approach to constructing large structural mechanisms has been proposed, which can be divided into three steps: selection of suitable tilings, construction of overconstrained units and validation of compatibility. This approach has been successfully applied to the construction of the structural mechanisms based on Bennett linkages and hybrid Bricard linkages. Several possible configurations are discussed including those described previously. All of the novel structural mechanisms presented in this dissertation contain only revolute joints, have a single degree of mobility and are geometrically overconstrained. Research work reported in this dissertation could lead to substantial advancement in building large spatial deployable structures.
88

Genome-wide SNP identification and QTL mapping for black rot resistance in cabbage

Lee, Jonghoon, Izzah, Nur K., Jayakodi, Murukarthick, Perumal, Sampath, Joh, Ho J., Lee, Hyeon J., Lee, Sang-Choon, Park, Jee Y., Yang, Ki-Woung, Nou, Il-Sup, Seo, Joodeok, Yoo, Jaeheung, Suh, Youngdeok, Ahn, Kyounggu, Lee, Ji Hyun, Choi, Gyung Ja, Yu, Yeisoo, Kim, Heebal, Yang, Tae-Jin January 2015 (has links)
BACKGROUND: Black rot is a destructive bacterial disease causing large yield and quality losses in Brassica oleracea. To detect quantitative trait loci (QTL) for black rot resistance, we performed whole-genome resequencing of two cabbage parental lines and genome-wide SNP identification using the recently published B. oleracea genome sequences as reference. RESULTS: Approximately 11.5 Gb of sequencing data was produced from each parental line. Reference genome-guided mapping and SNP calling revealed 674,521 SNPs between the two cabbage lines, with an average of one SNP per 662.5 bp. Among 167 dCAPS markers derived from candidate SNPs, 117 (70.1%) were validated as bona fide SNPs showing polymorphism between the parental lines. We then improved the resolution of a previous genetic map by adding 103 markers including 87 SNP-based dCAPS markers. The new map composed of 368 markers and covers 1467.3 cM with an average interval of 3.88 cM between adjacent markers. We evaluated black rot resistance in the mapping population in three independent inoculation tests using F₂:₃ progenies and identified one major QTL and three minor QTLs. CONCLUSION: We report successful utilization of whole-genome resequencing for large-scale SNP identification and development of molecular markers for genetic map construction. In addition, we identified novel QTLs for black rot resistance. The high-density genetic map will promote QTL analysis for other important agricultural traits and marker-assisted breeding of B. oleracea.
89

The Complex Genetics of Multiple Sclerosis : A preliminary study of MS-associated SNPs prior to a larger genotyping project

Söderholm, Simon January 2016 (has links)
Biomedical research have been revolutionized by recent technological advances, both in the fields of molecular biology and computer science, turning the biomolecular and genetic research into “big data science”. One of the main objectives have been to improve our understanding of complex human diseases. Among those diseases, multiple sclerosis (MS) is considered as one of the most common. MS is a chronic autoimmune disease that cause inflammation and damage to the central nervous system. In this study, a set of bioinformatics analyses have been conducted on SNP data, as an initial step to gain more information prior to an upcoming genotyping project. The results showed extensive regulatory properties for the 761 selected SNPs, which is consistent with current scientific knowledge, and also identified another 332 SNPs in linkage to these. However, during the study some issues have also been identified, which need to be addressed going forward.
90

Linkage analysis and lignin peroxidase gene expression in Phanerochaete chrysosporium

Allsop, Simon 12 1900 (has links)
Thesis (MSc)- Stellenbosch University, 2001. / ENGLISH ABSTRACT: Wood is composed of three main components: cellulose, hemicellulose and lignin. Cellulose is the main structural polymer, whereas the function of lignin in plants is to impart rigidity to the cells, to waterproof the vascular system, and to protect the plant against pathogens. A group of microorganisms, called white-rot fungi, are able to selectively degrade the lignin and hemicellulose from wood leaving the cellulose virtually untouched. The most widely studied fungus of this group is the basidiomycete Phanerochaete chrysosporium, which has become a model organism in studies of lignin degradation. Lignin is a large, heterogenous and water insoluble polymer and therefore the enzymes needed to degrade it have to be extracellular and non-specific. There are a number of enzymes that are involved in the degradation of lignin, including lignin peroxidases, manganese dependent peroxidases and laccases. Laecases are blue copper oxidases that require molecular oxygen to function, whereas lignin peroxidases and manganese peroxidases are heme proteins that require hydrogen peroxide. Phanerochaete chrysosporium has all three of these enzymes, as well as a system for producing the hydrogen peroxide that is necessary for peroxidases to function. For both scientific and industrial purposes, it is important to obtain linkage maps of the positions of genes in the genome of an organism. Most fungi, including P. chrysosporium, lack easily identifiable phenotypical markers that can be used to map the position of genes relative to each other on the genome. Previous methods of mapping genes in P. chrysosporium involved auxotrophic mutants, radioactivity, or the use of hazardous chemicals. Here we describe an automated DNA-sequencing based mapping technique that eliminates many of the problems associated with previous techniques. Portions of the genes to be mapped were amplified from homokaryotic single basidiospore cultures using gene specific primers using the polymerase chain reaction (PCR) technique. The PCR products were sequenced to determine the segregation of alleles. Two previously mapped lignin peroxidases, lipA and lipC, were used to develop this method, and the results obtained corresponded to the known genetic linkage. A newly characterised 13-glucosidase encoding gene from P. chrysosporium was also mapped. Linkage was found between the 13-glucosidase gene and a histone (Hl) encoding gene. In P. chrysosporium the lignin peroxidase isozymes are encoded by a family of at least ten genes. Previous studies with P. chrysosporium BKM-F-1767 in defined media, wood and soil have shown differential expression of the lignin peroxidase isozymes. In this investigation the levels of expression of lignin peroxidases in P. chrysosporium ME446 cultures grown in nitrogen or carbon limited defined liquid media, as well as on aspen wood chips were determined by competitive reverse transcriptase polymerase chain reaction (RT-peR). These results were compared to those previously obtained from P. chrysosporium BKM-F-1767 to evaluate strain specific variation in the expression of lignin peroxidases. The results indicate that, although there were many similarities in the patterns of lignin peroxidase expression, there were also enough differences to conclude that there were strain specific variations in the temporal expression of the lignin peroxidases. To conclude, a fast and cost effective method for mapping genes in P. chrysosporium was developed. Also, we showed that strain specific variation in temporal expression of lignin peroxidases occurs. / AFRIKAANSE OPSOMMING: Hout bestaan uit drie hoof komponente nl. sellulose, hemisellulose en lignien. Sellulose is die hoof strukturele polimeer, terwyl die funksie van lignin in plante is om die selle te versterk, die vaskulêre sisteem waterdig te hou, en die plant teen patogene te beskerm. 'n Groep mikroërganisms, bekend as witvrotswamme, kan lignien en hemisellulose selektief uit die hout verwyder, terwyl die sellulosevesels oorbly. Vanuit hierdie groep swamme is die meeste navorsing op die basidiomiseet Phanerochaete chrysosporium gedoen Lignien is 'n groot, heterogene polimeer en is onoplosbaar in water. Die ensieme wat benodig word om lignien afte breek is daarom nie-spesifiek en kom ekstrasellulêr voor. 'n Aantal ensieme is by die afbraak van lignien betrokke, insluitend lignienperoksidase, mangaanperoksidase en lakkase. Lakkase is 'n blou koperoksidase wat suurstof benodig vir aktiwiteit. Lignienperoksidase en mangaanperoxidase is heemproteïene en benodig waterstofperoksied. Phanerochaete chrysosporium het al drie van hiedie ensieme, sowel as 'n sisteem wat waterstofperoksied produseer. Vir beide wetenskaplike en nywerheidsdoeleindes is koppelingskaarte wat die posisie van gene in die genoom van 'n organisme aandui noodsaaklik. Die meeste swamme, P. chrysosporium ingesluit, het geen fenotipiese merkers wat maklik van mekaar onderskei kan word nie, en dit is dus moeilik om 'n kaart van die ligging van gene op die genoom te bepaal. Vorige metodes om gene in P. chrysosporium te karteer het auksotrofiese mutante, radioaktiwiteit of gevaarlike chemikalieë gebruik. Ons beskryf 'n metode wat van automatiese DNA-volgordebepaling gebruik maak en wat baie van die tekortkominge van die ou metodes oorkom. Dele van die gene is met geen-spesifieke PKR-amplifikasie uit kulture van homokariotiese enkel basidiospore verkry en die DNA-volgorde is bepaal om die segregasie van die allele te ondersoek. Twee gene waarvoor 'n koppelingskaart alreeds uitgewerk is, fipA en lipt), was gebruik om hierdie metode te ontwikkel. Die resultate stem ooreen met die bekende genetiese koppeling tussen hierdie gene. 'n Geen wat onlangs in P. chrysosporium ontdek is, nl. I3-glucosidase, is ook met hierdie metode gekarteer. Koppeling is met 'n histoon (Hl) geen gevind. Die lignienperoksidase isoensieme in P. chrysosporium word deur 'n familie van ten minste tien gene gekodeer. Vorige navorsing met P. chrysosporium BKM-F-1767 in gedefineerde media, hout en grond het getoon dat 'n variasie in die uitdrukking van lignienperoxidase isoensieme voorkom. In hierdie ondersoek is 'n kultuur van P. chrysosporium ME446 in stikstof- of koolstof-beperkende vloeibare media opgegroei, as ook op aspen houtblokkies. Die vlak van uitdrukking van die lignienperoksidases is deur middel van die omgekeerde transkripsie polimerasekettingreaksie (RT-PKR) bepaal. Die resultate vir P. chrysosporium ME446 is vergelyk met vorige resultate van P. chrysosporium BKM-F-1767 om te bepaal of stamspesifieke variasies in die uitdrukking van lignienperoksidases voorkom. Daar is 'n aanduiding dat, alhoewel soortgelyke patrone in die vlakke van lignienperoksidase uitdrukking voorkom, daar ook noemenswaardige verskille is. Hieruit kan afgelui word dat stamverwante variasie van lignienperokisdase uitdrukking voorkom. Ten slotte, ons het 'n vinnige, goedkoop metode om die gene in P. chrysosporium te karteer ontwikkel. Ons het ook bewys dat stam-spesifieke variasie in die uitdrukking van die lignienperoxidase gene voorkom.

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