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Kayim, Mehmet. "Founder Effect In Reintroduced Anatolian Mouflon Ovis Gmelinii Anatolica Valenciennes 1856 Populations." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/3/12610015/index.pdf.
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Reintroduction of Anatolian mouflon population at Bozdag Protection &<br>Breeding Station to its former habitats(Emremsultan Wildlife Development Area in Ankara-Nallihan, and Karadag in Karaman) started in 2004. The magnitude of genetic change among Bozdag and reintroduced populations was evaluated by 11 microsatellite loci. Study populations revealed close results (±<br>st.dev.) &ndash<br>Bozdag population: nk = 2.9091 (±<br>1.1362), AE = 2.0250 (±<br>0.9537), Ho = 0.3830 (±<br>0.2717), He = 0.3956 (±<br>0.2746)<br>Nallihan population: nk = 2.9091 (±<br>1.1362), AE = 2.0592 (±<br>0.9451), Ho = 0.4086 (±<br>0.2977), He = 0.4052 (±<br>0.2767)<br>and Karadag population: nk = 2.5455 (±<br>1.1282), AE = 1.8809 (±<br>0.8758), Ho = 0.3388 (±<br>0.2775), He = 0.3607 (±<br>0.2716). Population differences for major genetic parameters were not significant (p ><br>0.05) by comparisons with paired t-test. Also, temporal change in genetic diversity for Bozdag population was investigated by comparison with temporal data. Temporal changes in genetic parameters were found to be not significant and possible causes for differences were argued. Additionally, genetic diversity and PI computations for different traps were verified and compared to uncover any potential bias due to the catching method. Comparisons did not reveal significant differences illustrating the homogeneity among traps. On the other hand, simulations detected the higher sensitivity of allelic diversity (A) to founder events than P and heterozygosity (Ho &<br>He) levels which supports heterozygosity excess method for bottleneck analysis. With the same simulation analysis, observed genetic diversity within reintroduced samples were found to be in the ranges of expectation (99% CI) indicating that translocated individuals were chosen randomly. Bottleneck analysis based on heterozygosity excess method (one-tailed test for heterozygosity excess: pSMM = 0.28515, pTPM = 0.06445, pIAM = 0.02441) and allele frequency distributions method (normal L-shaped) could not detect a recent genetic bottleneck for Bozdag population. However, simulations determined that these two methods are prone to type II error. Bottleneck detection failure for the study population is probably due to type II error instead of other sources of error like violations of model assumptions.
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Väisänen, M. L. (Marja-Leena). "Fragile X syndrome in Northern Finland:molecular, diagnostic and population genetic aspects." Doctoral thesis, University of Oulu, 1999. http://urn.fi/urn:isbn:9514253779.
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Abstract
Fragile X syndrome, the most common inherited form of mental retardation syndrome, is caused by an expansion of the CGG trinucleotide repeat in the 5' UTR of the FMR1 gene, with concurrent hypermethylation of the region, which represses FMR1 expression. The syndrome is associated with the folate-sensitive chromosomal fragile site at Xq27.3 (FRAXA), where the gene responsible for the syndrome was first localized by linkage analysis using RFLP markers. In this study the linkage relationships of the RFLP markersat Xq27-28 and the characteristics of the CGG repeat expansion were investigated in northern Finnish fragile X families and molecular diagnostic methods were applied in order to improve diagnosis of the syndrome. Furthermore, the origin of fragile X mutations in the northern part of Finland was studied by haplotype analysis.
Linkage studies were performed in 34 northern Finnish fragile X families/pedigrees using a total of 15 RFLPs (defining 11 loci). A refined genetic map around FRAXA including five RFLP markers having recombination fractions of 0.04 or less with FRAXA was obtained in an international study of 112 affected families, containing linkage data on twelve northern Finnish families. Linkage analysis significantly improved carrier detection in fragile X families compared with previous cytogenetic methods used in diagnosis. The most efficient RFLP-based protocol for carrier detection was proposed, which is based on use of the most adjacent markers and a minimum number of restriction enzymes.
CGG repeat expansion of the FMR1 gene was investigated in original families collected for linkage studies and additional new ones. Large CGG repeat expansions (Δ > 500 bp) with concomitant methylation of the adjacent CpG island, i.e. full mutations, were found to be associated with mental retardation completely in males, but only 50% of the females having a full mutation were mentally impaired. Premutations (Δ < 700 bp) were found in healthy carriers. There was a size range of Δ = 500 to 700 bp, where the expansions could be either abnormally methylated or non-methylated, and it appeared that methylation is more important in determining the phenotype than the exact size of an expansion. Instability of the enlarged CGG repeats was detected, leading preferentially to size increases in successive generations. The instability of premutations was found to be stronger and the size increases larger in maternal than in paternal transmissions, and transition to a full mutation occurred only in female transmissions. In addition, the size of a maternal premutation was shown to have an important influence on the risk of its transition to a full mutation when transmitted. The critical premutation size leading invariably to full mutation in the offspring was found to be between Δ = 175 to 200 bp. In one of the studied families a rare contraction of a paternal premutation to a normal CGG repeat number in one of the daughters and further in her son was detected. Direct mutation analysis including measurement of the CGG repeat size and hypermethylation allowed unambiguous diagnosis of carriers and affected individuals in most cases.
Haplotype analysis using two tightly linked microsatellite markers flanking the CGG repeat mutation was performed in 60 unrelated northern and eastern Finnish fragile X families. A significant difference was found in allelic and haplotypic distributions between normal X and fragile X chromosomes. A single haplotype, which was present only in 8% of the normal X chromosomes, accounted for 80% of the fragile X chromosomes. This enrichment of one fra(X) mutation in the Finnish population suggests founder effect.
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Love-Gregory, Latisha Debrett. "Investigation of the origin of the Y393N allele in old order mennonite and non-mennonite maple syrup urine disease patients : analysis of the branched chain [alpha]-keto acid dehydrogenase complex E1[alpha] gene /." free to MU campus, to others for purchase, 2001. http://wwwlib.umi.com/cr/mo/fullcit?p3012999.
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Osmers, Karl Benjamin. "Genetic structuring between gemsbok (oryx gazella) populations and the impact of the founder effect on isolated populations." Thesis, University of Limpopo (Turfloop Campus), 2012. http://hdl.handle.net/10386/746.
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Thesis (M.Sc. (Zoology)) --University of Limpopo, 2012<br>A microsatellite-based study was performed on five populations of Gemsbok (Oryx gazella). This study was aimed at estimating genetic diversity in introduced South African gemsbok populations (an opportunity that arose when additional animals from the same source were imported into South Africa), and determine genetic structure. Population sizes at the time of sampling were: Namibia (n = 6500), Cohen (n = 70), Tempelhof (n = 55), STS Kalahari Game Ranch (n = 1000) and Elias (n = 35). The purpose of the study was to determine the genetic structure of the aforementioned O. Gazelle populations, and to assess the impact of the founder effect on isolated populations. The following primers (BMS1237, MAF46, OARFC304, OARHH64, ETH225, RBP3, MAF50, HDZ8) developed for commercial purposes in the bovine group were used. Genetic diversity were calculated as Expected Heterozygosity (He), proportion of polymorphic loc (P) and number of alleles per locus (A). Conformation to expected Hardy-Weinberg equilibrium of genotypes was also determined, using a Chi-square test. Tests for the signature of bottlenecks in the populations studied were also performed. Genetic drift/differentiation was tested by using FST and RST coefficients. Assignment tests were performed to identify the true number of genetic populations (clusters). Genetic distance was used as an additional measure of differentiation. The results indicated that all loci showed allelic polymorphism in all the populations except one (at the OARHH64 locus). The South African Cohen population displayed the highest level of genetic diversity, with He = 0.595 ± 0.247. This population also did not show evidence of a bottleneck. Genetic distance values indicated the greatest similarity between the Cohen and Namibian populations, in line with the Namibian origin of the Cohen group. Greatest distance was observed between the STS and Tempelhof populations. conclusion, results from this study reflects the origins of populations and suggest that inbreeding in small isolated populations may be less than previously estimated.
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Broders, Hugh G. "Population genetic structure and the effect of founder events on the genetic variability of moose (Alces alces) in Canada." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape10/PQDD_0035/MQ47418.pdf.
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Parsons, Donald Williams. "Intragenic SMN mutations : frequency, distribution, evidence of a founder effect, and modification of SMA phenotype by centromeric copy number /." The Ohio State University, 1999. http://rave.ohiolink.edu/etdc/view?acc_num=osu1488190109869324.
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Norgren, Nina. "Hereditary transthyretin amyloidosis (ATTR V30M) : from genes to genealogy." Doctoral thesis, Umeå universitet, Medicin, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-84494.
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Background: Hereditary transthyretin amyloidosis is an autosomal dominant disease with a reduced penetrance. The most common mutation in Sweden is the V30M mutation in the transthyretin gene. Clustering areas of the disease can be found in Northern Sweden, Portugal, Brazil and Japan, although sporadic cases exist worldwide. Despite being caused by the same mutation, there are large differences in onset, penetrance and symptoms of the disease. Swedish V30M patients typically have a later onset with a lower penetrance compared to those from the clustering Portuguese V30M areas. The reasons for these differences have not been fully understood. The aim of this thesis is to study mechanisms that may influence onset and symptoms and investigate why patients carrying the same mutation have different phenotypes. Methods: Genealogy studies were performed on all known V30M carriers in Sweden using standard genealogy methods. DNA samples from patients, asymptomatic carriers and controls from different countries were collected and the transthyretin gene was sequenced. Liver biopsies from patients were used for allele specific expression analysis and a cell assay was used for miRNA analysis with the mutated allele. Gene expression analysis was performed on biopsies from liver and fat from patients and controls. Results and conclusions: Genealogic analysis of all known Swedish V30M carriers managed to link together 73% of the Swedish ATTR V30M population to six different ancestors from the 17th and 18th century, thus dating the Swedish V30M mutation to be more than 400 years old. A founder effect was also visible in descendants to one of the ancestors, producing a later age at onset. Sequencing of the transthyretin gene revealed a SNP in the 3’ UTR of all Swedish V30M carriers that was not found in any of the Japanese or French V30M carriers. The SNP was present on the Swedish transthyretin haplotype and defined the Swedish V30M population as separate from others. However, the SNP itself had no effect upon phenotype or onset of disease. Gene expression analysis of liver and fat tissue revealed a change in genetic profile of the patients’ livers, in contrast to the unchanged profile of the fat tissue. A changed genetic profile of the liver could explain why domino liver recipients develop the disease much earlier than expected.
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Jonasson, Jenni. "Genetic and Molecular analysis of the Spinocerebellar ataxia type 7 (SCA7) disease gene." Doctoral thesis, Umeå universitet, Medicinsk och klinisk genetik, 2000. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-1900.
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Spinocerebellar ataxia type 7 (SCA7) is a hereditary neurodegenerative disorder affecting the cerebellum, pons and retina. SCA7 patients present with gait ataxia and visual impairment as the main symptoms. Anticipation, commonly observed in SCA7 families, is a phenomenon where an earlier age at onset and a more severe progression of disease is seen in successive generations. In order to identify the gene responsible for SCA7, we performed linkage analysis on a Swedish SCA7 kindred. Evidence for linkage of the SCA7 disease locus to a 32 cM region on chromosome 3p12-21.1, between markers D3S1547 and D3S1274, was established. A number of neurodegenerative disorders associated with anticipation are caused by expanded (CAG)n repeats in their respective disease genes. In order to isolate the SCA7 disease gene we, therefore, screened a human infant brain stem cDNA library for CAG repeat containing clones, mapping to chromosome 3. Four candidate clones were isolated and analysed, but could all be excluded as the SCA7 disease gene. In 1997, the SCA7 disease gene was identified and, as expected, shown to harbour a CAG repeat, expanded in SCA7 patients. Analysis of the SCA7 CAG repeat region in Swedish SCA7 patients demonstrated that CAG repeat size was negatively correlated to age at onset of disease. Furthermore, patients with larger repeats presented with visual impairment, whereas patients with smaller repeats presented with ataxia as the initial symptom. SCA7 is the most common autosomal dominant cerebellar ataxia in Sweden and Finland, but rare in other populations. In order to investigate if the relatively high frequency of SCA7 in these countries is the result of a founder effect in the region, a haplotype analysis was performed on all SCA7 families available. All 7 families shared a common haplotype of at least 1.9 cM surrounding the SCA7 locus. In addition, strong linkage disequilibrium was demonstrated for marker D3S1287 closely linked to the SCA7 gene, suggesting a founder effect for the SCA7 mutation in Sweden and Finland. The function of the SCA7 protein, ataxin-7, is not known and it does not show significant homologies to any previously known proteins. In order to gain insight into the function of ataxin-7 we analysed the expression of ataxin-7 in brain and peripheral tissue from SCA7 patients and controls. In brain, expression was found to be mainly neuronal with a nuclear subcellular localisation. Ataxin-7 expression was found throughout the CNS, not restricted to sites of pathology. We also confirmed previously reported findings of neuronal intranuclear inclusions (NIls) in the brains of SCA7 patients. Based on our findings, we conclude that the cell type specific neurodegeneration in SCA7 is not due to differences in expression pattern in affected and non-affected tissue or the distribution pattern of aggregated protein.
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Deus, Daiane Beneduzzi de. "Estudo do gene do receptor de GnRH (GNRHR) no hipogonadismo hipogonadotrófico isolado normósmico e atraso constitucional do crescimento e desenvolvimento." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/5/5135/tde-02012014-165016/.
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Mutações inativadoras do receptor de GnRH (GNRHR) são a causa genética mais frequente de hipogonadismo hipogonadotrófico isolado (HHI) normósmico. Os genes envolvidos da patogênese do HHI, incluindo o GNRHR, estão associados a um amplo espectro fenotípico, variando de HHI parcial a completo. O atraso constitucional do crescimento e desenvovimento (ACCD) poderia constituir uma variante fenotípica leve do HHI. Neste estudo avaliamos a frequência de mutações no gene GNRHR em pacientes com HHI normósmico e ACCD, bem como correlacionamos o genótipo/fenótipo nesses pacientes. Além disso, avaliamos o efeito fundador de uma mutação do GNRHR (p.R139H) frequente na população brasileira com HHI normósmico. Para esse estudo, selecionamos 116 pacientes com HHI normósmico e 51 com ACCD. Um grupo de 130 indivíduos com desenvolvimento puberal normal foi utilizado como controle. A região codificadora do gene GNRHR foi amplificada por PCR e sequenciada. Análises in silico e in vitro foram realizadas nas duas novas variantes (p.V134G e p.Y283H). Três marcadores de microssatélites (D4S409, D4S2387, D4S3018) foram amplificados e analisados nos pacientes portadores da mutação p.R139H, familiares e controles. No grupo de HHI normósmico, nove mutações (p.N10K,p.Q11K, p.Q106R, p.R139H, p.C200Y, p.R262Q, p.Y284C, p.Y283H, p.V134G) foram identificadas em onze pacientes (9,5%). Entre as mutações identificadas no GNRHR, duas foram descritas pela primeira vez no estudo atual: p.Y283H e p.V134G, cuja análise in vitro demonstrou inativação completa do receptor. Em geral, uma boa correlação genótipo-fenótipo foi observada. Pacientes portadores de mutações inativadoras apresentavam HHI completo e mutações com perda parcial de função causavam HHI parcial, incluindo dois pacientes que evoluíram com reversão do hipogonadismo após reposição androgênica. Por outro lado, não houve diferença fenotípica entre os casos com e sem mutação do GNRHR. Análise de ancestralidade genética da mutação p.R139H demonstrou que todos os casos brasileiros apresentaram o mesmo haplótipo, sugerindo que a mutação p.R139H possui um ancestral comum na população brasileira. Por outro lado o caso familial proveniente da Polônia apresentou apenas um marcador em comum com as famílias brasileiras e estudos mais abrangentes seriam necessários para determinar a origem da mutação p.R139H em indivíduos não Brasileiros. Na casuística de ACCD apenas a mutação p.Q106R foi identificada no gene GNRHR em heterozigose em um paciente. Em conclusão, o GNRHR foi o gene mais comumente afetado, apresentando uma boa correlação genótipo-fenótipo, e deve ser o primeiro candidato para análise genética em HHI normósmico. Os resultados sugerem que a mutação p.R139H possui um ancestral comum na população brasileira. Mutações no GNRHR parecem não estar envolvidas na patogênese do ACCD<br>GnRH receptor (GNRHR) inactivating mutations are the most common genetic cause of normosmic IHH. The genes involved in the IHH, including GNRHR, have been associated with a large phenotypic spectrum, varying from partial to complete IHH. Constitutional delay of growth and puberty (CDGP) might represent a mild phenotypic variant of IHH. In this study we investigated novel variants and characterized the frequency and phenotype-genotype correlation of GNRHR mutations in normosmic IHH and CDGP patients. Additionally, we determined de cause of the recurrence of GNRHR p.R139H mutation in patients with normosmic IHH. We studied 116 patients with normosmic IHH and 51 with CDGP. The control group was composed by 130 adults with normal pubertal development. The coding region of GNRHR was amplified and automatically sequenced. The two novel variants identified (p.Y283H, p.V134G) were submitted to in silico and in vitro analysis. Three microsatellite markers (D4S409, D4S2387, D4S3018) were amplified by PCR and analyzed in the patients with the p.R139H mutation. In the CDGP group, the previously described mutation p.Q106R was identified in the heterozygous state in one boy. The p.Q106R mutation has been identified in heterozygous state in individuals with normal pubertal development and does not appear be involved on the CDGP phenotype in this patient. In the normosmic IHH group, nine variants were identified (p.N10K, p.Q11K, p.Q106R, p.R139H, p.C200Y, p.R262Q, p.Y284C, p.Y283H, p.V134G) in eleven patients (9.5%). In vitro analysis of the novel variants p.Y283H and the p.V134G demonstrated that both of them cause complete loss of function of the receptor. The founder effect study revealed that all the p.R139H affected Brazilian patients presented the same haplotype, suggesting that the this mutation has a common ancestor in the Brazilian population. Nevertheless the affected Polish family presented a different haplotype, with only one marker in common with the Brazilian families and further studies would be necessary to determine the origin of the p.R139H mutation in the European population. In conclusion this study demonstrated that GNRHR was the most commonly affected gene in normosmic IHH, with a good genotype-phenotype correlation, and should be the first candidate gene for genetic screening in this condition. The results of the founder effect study suggested that the p.R139H mutation has a common ancestor in the Brazilian population. Finally, mutations in the GNRHR do not appear to be involved in the pathogenesis of CDGP
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Borges, Luciana Moreira. "VALOR PREDITIVO DA MUTAÇÃO R337H DO GENE TP53 COMO UM MARCADOR CLÍNICO EM PACIENTES COM CÂNCER." Pontifícia Universidade Católica de Goiás, 2014. http://localhost:8080/tede/handle/tede/2379.
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Previous issue date: 2014-04-07<br>Introduction: the R337H mutation of the TP53 gene was originated in the Brazilian population through a founder effect and is considered a molecular defect of low penetrance. In combination with some polymorphisms, the R337H mutation can increase the susceptibility to tumor. The frequency of the R337H mutation in Brazilian families is considered high when compared to the observed frequencies in other countries. The unambiguous association between the mutation, the emergence of different tumor types and the high number of individual that carry the mutation makes the R337H a relevant factor in public health, particularly in the prediction of cancer. Objective: This study aimed to investigate the predictive value of the R337H mutation of the TP53 gene as a clinical marker in cancer patients. Method: a systematic literature review (SLR) was carefully performed, by searching electronic scientific literature in LILACS, IBECS, MEDLINE, Pubmed and SciELO. Twelve articles, published in English between the years 2006 to 2013, were selected by performed the relevance tests I and II. Extraction of detailed data was independently performed by two investigators, following on extraction data protocol. Results: the R337H mutation was found in 287 of 1,548 patients with cancer, two of 750 women considered healthy, 200 of 887 family members of patients with adrenocortical tumor (ACT) carrying the R337H mutation, 12 of 647 health controls and in 442 of 171 630 newborns. Eight of the twelve selected references associated the R337H mutation with family history of 411 patients with the mutation. Four studies associated the R337H mutation prognosis. Conclusion: the frequency of the R337H mutation of the TP53 gene is considerably higher in the south and southeast regions of Brazil compared to other countries. The mutation was associated with family history of cancer, the increase of the positive predictive value and the decreased of negative predictive value at diagnosis, and poor prognosis in ACT and CPC patients with with the mutation.<br>Introdução: a mutação R337H do gene TP53 foi originada na população brasileira por efeito fundador e é considerada um defeito molecular de baixa penetrância. Em combinação com alguns polimorfismos, a mutação R337H, pode aumentar a susceptibilidade ao desenvolvimento do tumor. A frequência da mutação R337H em famílias brasileiras é considerada elevada, quando comparada com as frequências observadas em outros países. A inequívoca associação entre a mutação, o surgimento de diferentes tipos tumorais e o alto número de indivíduos portadores da mutação fazem da R337H um relevante fator de saúde pública, em especial na predição do câncer. Objetivos: este estudo objetiva de investiga o valor preditivo da mutação R337H do gene TP53 como um marcador clínico em pacientes com câncer. Método: revisão bibliográfica sistemática (RBS) criteriosa foi realizada, através de busca eletrônica de artigos científicos nas bases de dados LILACS, IBECS, MEDLINE, Scielo e Pubmed. Doze artigos selecionados foram publicados em língua inglesa entre os anos de 2006 à 2013, foram selecionados para aplicação dos testes de relevância I e II. Extração de dados detalhada foi realizada de forma independente por dois investigadores seguindo o protocolo para extração de dados. Resultados: a mutação R337H foi encontrada em 287 dos 1.548 portadores de câncer, duas das 750 mulheres consideradas saudáveis, 200 dos 887 familiares de pacientes portadores de tumor do córtex adrenal (TCA) com a mutação R337H, doze dos 647 controles e 442 dos 171.630 recém-nascidos. Oito das doze referências selecionadas associaram a mutação R337H com histórico familiar de 411 pacientes com a mutação. Quatro estudos associaram a mutação R337H com o prognóstico. Conclusão: a frequência da mutação R337H do gene TP53 é consideravelmente mais elevada no sul e sudeste do Brasil quando comparada com os demais países do mundo. A mutação foi associada com: histórico familiar de câncer, aumento do valor preditivo positivo e diminuição do valor preditivo negativo no diagnóstico e mal prognóstico em pacientes com ACT e CPC com a mutação.
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Pinto, Emilia Modolo. "Presença da mutação Arg337His do supressor tumoral P53 e mapa de deleção do cromossomo 17 em crianças e adultos com tumores adrenocorticais." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/5/5160/tde-07102014-094643/.
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A incidência dos tumores adrenocorticais na região sul do Brasil é 10-15 vezes maior que a incidência mundial. Mutações no gene supressor tumoral p53, localizado na região 17p13.1 têm sido identificadas em diversos tumores humanos. Uma distinta mutação germinativa, Arg337His, localizada no domínio de tetramerização da proteína supressora tumoral P53 foi identificada em 35 de 36 crianças da região sul do Brasil. No presente trabalho, investigamos a presença da mutação Arg337His em 71 pacientes não relacionados, 41 adultos e 30 crianças, portadores de tumores adrenocorticais benignos e malignos. Adicionalmente, análise de perda de heterozigose do locus p53, mapa de deleção do cromossomo 17 e instabilidade cromossômica foram estudados em DNA genômico destes pacientes. Nenhum dos pacientes estudados apresentava histórico familial compatível com a síndrome de Li-Fraumeni. Sequenciamento automático permitiu a identificação da mutação Arg337His, em DNA extraído a partir de sangue periférico e/ou tecido tumoral, em 29 (24 crianças e 5 adultos) dos 71 pacientes. Nas 10 famílias em que foi possível analisar o DNA genômico de ambos os pais verificamos que a mutação Arg337His tem caráter hereditário. Por outro lado, esta mutação não foi encontrada em DNA de 160 indivíduos do grupo controle, não relacionados, analisados por sequenciamento automático e/ou digestão enzimática. A análise pareada de DNA gênomico de sangue periférico e de tecido tumoral revelou perda de heterozigose para o locus p53 em 18 de 21 (86%) pacientes portadores da mutação Arg337His. Não observamos correlação entre a presença desta mutação e o comportamento maligno dos tumores. O estudo de dois marcadores polimórficos intragênicos do p53, pelo programa de análise de tamanho de fragmento GeneScan, evidenciou um mesmo haplótipo associado à mutação Arg337His em 91% dos pacientes com tumores adrenocorticais, configurando uma origem comum para esta mutação. O estudo de 6 marcadores polimórficos ao longo do cromossomo 17 (D17S926, VNTRP53, D17S1856, D17S942, D17S1351 e D17S928) em DNA genômico pareado de 29 pacientes demonstrou uma freqüência elevada (81%) de perda do cromossomo 17 em associação à mutação Arg337His. Não observamos correlação entre a perda do cromossomo 17 e a agressividade tumoral nestes pacientes. Instabilidade cromossômica envolvendo os cromossomos 2, 9 e 11 nos 17 pacientes que perderam o cromossomo 17 foi identificada em 47%, 47% e 71%, respectivamente. Perda dos cromossomos 2 e 11 foi evidenciada em tumores benignos e malignos. A perda do cromossomo 9 foi evidenciada exclusivamente nos tumores malignos, assim como a perda concomitante de 3 ou mais cromossomos. Em conclusão, confirmamos uma freqüência elevada da mutação Arg337His em crianças brasileiras com tumores adrenocorticais benignos e malignos. Esta mutação também foi encontrada no grupo de adultos, embora em menor freqüência. Não houve correlação entre sua presença e o comportamento maligno dos tumores adrenocorticais. Efeito fundador para a mutação Arg337His e inativação bialélica do p53, caracterizada pela presença da mutação Arg337His e a perda do cromossomo 17 foram demonstradas na maioria dos casos analisados. Finalmente, a instabilidade cromossômica envolvendo três ou mais cromossomos contribuiu para o diagnóstico de carcinoma adrenocortical<br>The incidence of adrenocortical tumors in the South region of Brazil is 10 to 15 times higher than the worldwide one. Mutations in the tumor suppressor p53 gene, located in chromosome 17p13.1, have been described in different human tumors. A germline mutation, Arg337His, in the tetramerization domain of the tumor suppressor P53 was identified in 35 of 36 children from the South region of Brazil. In the present study we have searched for Arg337His mutation in genomic DNA of 71 non-related patients, 41 adults and 30 children, with benign or malignant adrenocortical tumors. Additionally, we also analyzed the loss of heterozigosity of p53 locus, deletion mapping of chromosome 17 and chromosome instability, in genomic DNA of these patients. None of the patients had a familial history of Li-Fraumeni syndrome. Automatic sequencing identified the Arg337His mutation in genomic DNA from peripheral leukocytes and/or tumor tissues in 29 (24 children and 5 adults) of these 71 patients. In 10 families in which the study of both parent\'s DNA was possible, the Arg337His mutation was inherited from one of the parents. Sequencing analysis and/or enzymatic restriction showed that this mutation was not present in DNA of 160 non-related control subjects. Paired analysis of genomic DNA of peripheral leukocytes and tumor tissue revealed loss of heterozigosity of p53 locus in 18/21 (86%) patients with Arg337His mutation. There was no correlation between the presence of this mutation and the malignant behavior of these tumors. The study of two intragenic polymorphic markers of p53 through GeneScan software showed the association of the same haplotype with the Arg337His mutation in 91% of patients with adrenocortical tumors, indicating a common origin of this mutation. The study of 6 polymorphic markers along chromosome 17 (D17S926, VNTRP53, D17S1856, D17S942, D17S1351, D17S928) in paired genomic DNA of 29 patients showed an increased frequency (81%) of chromosome 17 loss in association with the presence of the Arg337His mutation. We did not observe any correlation between the loss of chromosome 17 and aggressive tumor behavior in these patients. In the 17 patients who lost chromosome 17, chromosome instability of chromosomes 2, 9 and 11 was identified in 47%, 47% e 71%, respectively. Loss of chromosomes 2 and 11 was observed in benign and malignant tumors, whereas the loss of chromosome 9 was observed exclusively on malignant tumors. Similarly, the concomitant loss of 3 or more chromosomes was only observed in malignant tumors. In conclusion we confirmed an increased frequency of Arg337His mutation in Brazilian children with benign or malignant adrenocortical tumors. This mutation was also found in the adult group, although at a lower frequency. There was no correlation between the presence of the mutation and the malignant behavior of adrenocortical tumor. We demonstrated a founder effect for this mutation and also a biallelic inactivation of p53 characterized by the presence of the Arg337His mutation and the loss of chromosome 17 in most of the cases studied. Finally, chromosome instability involving 3 or more chromosomes contributed for the diagnosis of adrenocortical carcinoma in these
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Herzig, Anthony Francis. "Studying the genetic architecture of complex traits in a population isolate." Thesis, Sorbonne Paris Cité, 2019. http://www.theses.fr/2019USPCC110.
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Mon projet de thèse vise à exploiter le potentiel des isolats de population pour étudier la composante génétique des maladies multifactorielles. En effet, les isolats peuvent faciliter l'identification des facteurs génétiques habituellement trop rares en population générale. Cette thèse est composée de deux études principalement : l'imputation génétique et l'analyse de l'héritabilité. Chacune de ces études ont été abordée sous deux angles : l’un théorique, s’appuyant sur une vaste étude de simulations basée sur les caractéristiques de la population isolée du Cilento, permettant d’évaluer des stratégies d’analyse et de déterminer la plus adéquate ; l’autre appliqué, s’appuyant sur l’analyse de données génétiques réelles issues de la même population.L'imputation génétique est une étape cruciale pour effectuer des analyses d'association dans un isolat et représente une méthode peu couteuse pour obtenir les séquences complètes du génome ou de l’exome des individus de la population. L'efficacité de cette approche dépend de la précision de l’imputation ; nous avons donc étudié plusieurs stratégies pour obtenir une précision d'imputation maximale dans un isolat. Nous avons montré que les logiciels utilisant des algorithmes qui s’appuient sur les caractéristiques particulières des isolats n’étaient pas, de façon inattendue, aussi performants que ceux conçus pour les populations générales. De plus, malgré la disponibilité de panels de référence publics contenant plusieurs milliers de chromosomes, nous avons confirmé qu’un panel de référence spécifique de la population d’étude, même de taille très réduite, était essentiel pour la qualité de l’imputation. Ceci était d’autant plus vrai pour les variantes rares.Pour de nombreux traits, il existe des discordances entre les estimations de l'héritabilité obtenues à partir d’individus apparentés et à partir d’individus non apparentés. En particulier, la plupart des chercheurs considère que les effets dominants (non additifs) ne jouent pas un rôle majeur malgré les résultats contrastés des études sur les isolats. Notre deuxième analyse a révélé des mécanismes possibles pour expliquer la disparité de ces estimations publiées entre populations isolées et populations générales. Cela nous a permis de faire des déductions intéressantes pour nos propres analyses dans le Cilento. En particulier, nous avons identifié la possibilité d'une composante de dominance non nulle pour les niveaux de lipoprotéines de basse densité (LDL). Cela nous a amenés à effectuer des analyses d'association pan-génomique des composantes additives et non-additives pour LDL dans le Cilento et nous avons pu identifier des gènes qui avaient déjà été liés au trait dans d'autres études.Dans le contexte de nos deux études, nous avons observé l'importance de conserver l'incertitude génotypique (dosage pour l’imputation, vraisemblance des génotypes pour les données de séquençage). Dans la perspective de cette thèse, nous avons proposé des moyens d’incorporer cette incertitude à certaines méthodes utilisées dans ce projet.Nos résultats concernant les stratégies d'imputation et l'analyse de l'héritabilité seront très utiles pour la poursuite de l'étude de l'isolat de Cilento. Mais, ils seront également instructifs pour les chercheurs travaillant sur d'autres populations isolées et également applicables plus généralement à l'étude des maladies complexes<br>My thesis project is concerned with tapping the potential of population isolates for the dissection of complex trait architecture. Specifically, isolates can aid the identification of variants that are usually rare in other populations. This thesis principally contains in depth investigations into genetic imputation and heritability analysis in isolates. We approached both of these studies from two main angles; first from a methodological standpoint where we created extensive simulation datasets in order to investigate how the specificities of an isolate should determine strategies for analyses. Secondly, we demonstrated such concepts through analysis of genetic data in the known isolate of Cilento. Imputation is a crucial step to performing association analyses in an isolate and represents a cost-efficient method for gaining dense genetic data for the population. The effectiveness of imputation is of course dependent on its accuracy. Hence, we investigated the wide range of possible strategies to gain maximal imputation accuracy in an isolate. We showed that software using algorithms which specifically evoke known characteristics of isolates were, unexpectedly, not as successful as those designed for general populations. We also demonstrated a very small study specific imputation reference panel performing very strongly in an isolate; particularly for rare variants. For many complex traits, there exist discordances between estimates of heritabilities from studies in closely related individuals and from studies on unrelated individuals. In particular, we noted that most researchers consider dominant (non-additive) genetic effects as unlikely to play a significant role despite contrasting results from previous studies on isolates. Our second analysis revealed possible mechanisms to explain such disparate published heritability estimates between isolated populations and general populations. This allowed us to make interesting deductions from our own heritability analyses of the Cilento dataset, including an indication of a non-null dominance component involved in the distribution of low-density lipoprotein level measurements (LDL). This led us to perform genome-wide association analyses of additive and non-additive components for LDL in Cilento and we were able to identify genes that had been previously linked to the trait in other studies. In the contexts of both of our studies, we observed the importance of retaining genotype uncertainty (genotype dosage following imputation or genotype likelihoods from sequencing data). As a prospective of this thesis, we have proposed ways to incorporate this uncertainty into certain methods used in this project. Our findings for imputation strategies and heritability analysis will be highly valuable for the continued study of the isolate of Cilento but will also be instructive to researchers working on other isolated populations and also applicable to the study of complex diseases in general
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Reeves, Karyn. "Founder effects and related issues in Host-viral association studies." Thesis, Reeves, Karyn (2013) Founder effects and related issues in Host-viral association studies. PhD thesis, Murdoch University, 2013. https://researchrepository.murdoch.edu.au/id/eprint/16565/.
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Viruses such as HIV which replicate rapidly and with high transcription error rates may evade immune detection by mutating at key positions within the viral amino acid sequence. Large-scale host-viral association studies are conducted to identify positions of possible escape mutation in response to host immune pressure, with this pressure predominantly governed by genes within the human leukocyte antigen (HLA) complex. When transmission of the virus is HLA-associated, however, standard tests of association can be confounded by the relatedness of contemporarily circulating viral sequences, as sequences descended from a common ancestor may share inherited patterns of polymorphisms, termed „founder effects‟. A number of model-based methods utilizing inferred phylogenetic trees estimated from the observed viral sequences have been proposed to correct for this confounding, although such methods are typically computationally intensive and require specialist software for their implementation. In this thesis we propose an alternative empirical approach based on principal components analysis (PCA) which can be implemented using widely available software, and which adapts and extends methods currently used to control for population stratification in case-control genome-wide association studies. To accommodate data with small proportions commonly observed in host-viral studies we implement the PCA-based controlling procedure within a logistic regression framework using novel formulations motivated by the Frisch-Waugh-Lovell Theorem and demonstrate their utility in detecting true associations whilst minimizing confounding generated by founder effects via simulation. The approach is then extended to the multivariate setting through the adaptation of well-known techniques which expand the scope of host-viral analyses by accommodating possible linkages within the HLA and viral data.
The thesis concludes with a discussion of issues arising from the application of tail-based rejection regions and false discovery rates in large-scale analyses based on pooled contingency tables with varying margins. We argue that constraints imposed by the margins have implications overlooked in the rigid application of techniques developed for tests based on statistics with continuous distributions, but by leveraging the scale of such analyses it may be possible to consider local deviations between observed and expected p-value distributions to better identify hypotheses of interest.
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Winbo, Annika. "Long QT syndrome in Sweden : founder effects and associated cardiac phenotypes." Doctoral thesis, Umeå universitet, Pediatrik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-57724.
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Background: We aimed to increase the knowledge regarding the familial arrhythmogenic disorder Long QT Syndrome (LQTS) and its recessive variant Jervell and Lange-Nielsen Syndrome (JLNS) in Sweden, including prevalences and clinical phenotypes. A specific focus was directed towards two KCNQ1 mutations –p.Y111C and p.R518X- commonly identified in Swedish LQTS index cases. Methods: Cases and families with LQTS (p.Y111C or p.R518X) and JLNS were recruited via regional clinical practices, national referrals to the Clinical Genetics laboratory, Umeå University Hospital, and a national inventory. Molecular genetics methods were used for case ascertainment. Clinical data was obtained via medical records, a questionnaire, and/or an interview. Electrocardiograms were manually assessed. In p.R518X heterozygotes intra-familial phenotypic variability (QTc and cardiac events) was assessed by analysis of sequence variants (modifier genes). The origins of the mutations p.Y111C and p.R518X were investigated using genealogical and haplotype analysis (microsatellite markers). In families sharing a common haplotype mutation age and associated prevalence was analyzed using ESTIAGE and DMLE computer software. Results: We identified p.Y111C (170 mutation-carriers) and p.R518X (101 mutation-carriers) as two major causes of LQTS/JLNS in Sweden. LQTS phenotype was revealed to be relatively benign in p.Y111C and p.R518X (annual incidence of life-threatening cardiac events, before therapy 0.05% and 0.04%, respectively). Gender-specific effects of genetic modifiers on phenotypic expression were seen. A founder origin, approximately 600-700 years ago in two northern river valleys was established for p.Y111C and p.R518X, and a high prevalence of LQTS founder descendants suggested. A minimum JLNS prevalence of 1:200 000 in preadolescent Swedish children was revealed. JLNS phenotype was mainly severe, with a cumulative incidence of life-threatening cardiac events of 53% (annual incidence rate before therapy 5%) and four sudden deaths. Possible founder effects regarding four KCNQ1 mutations; p.Y111C (8%), p.R518X (50%), c.572_576del (17%) and p.Q530X (8%) together explained 83% of the JLNS mutation-spectrum in Sweden, consisting of 8 KCNQ1 mutations. Conclusion: The high prevalence of p.Y111C- and p.R518X-related LQTS as well as JLNS revealed in Sweden could be explained by the combination of mild clinical phenotypes in heterozygotes and strong founder effects present during the population development of northern Sweden. Increased knowledge regarding the occurrence of LQTS and JLNS as well as mutation- and/or genotype-specific data constitute prerequisites for possible improvement of patient management.
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Kohn, Deborah Diane. "Effects of genetic variability and founder number in small populations of an annual plant." Thesis, Imperial College London, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.286448.
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Bailey, Anastasia Veronica Graham. "The Knowledge Effects of Founders' Human and Social Capital on Entrepreneurship." The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1470758829.
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Sarantaus, Laura. "Germline mutations of BRCA1 and BRCA1 genes : founder effects and contribution to ovarian carcinoma in Finland." Helsinki : University of Helsinki, 2002. http://ethesis.helsinki.fi/julkaisut/laa/kliin/vk/sarantaus/.
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Jones, Benjamin Graham. "PERCEPTUAL DIALECTOLOGY OF NEW ENGLAND: VIEWS FROM MAINE AND THE WEB." UKnowledge, 2015. http://uknowledge.uky.edu/ltt_etds/11.
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Research into the dialects of the New England states (Connecticut, New Hampshire, Maine, Massachusetts, Rhode Island, and Vermont) has traditionally split the region into distinct geographic regions based upon variations in production, primarily along an East-West border. Generally, such regions have been considered relatively stable in terms of their variation (Labov, Ash and Boberg 2006); however, recent work in the area has found that the traditional dialect boundaries have begun to shift (c.f. Stanford, Leddy-Cecere and Baclawski 2012). Such research has focused on very specific regional changes in production, ignoring the perceptual salience of the features observed to be in flux. To date very few studies (Ravindranath and Fernandes 2014) have examined how New Englanders perceive the regional divisions, with emphasis on the collected regions while not focusing specifically on how regions view each other in terms of difference and similarity.
This study examines regional perceptions of dialects in the New England states as seen by a small subset of New Englanders, predominantly residents of Maine and Massachusetts, through two studies: one conducted using a new web-based approach and another using the traditional pen-and-paper method of perceptual dialectology. Speakers have been asked to identify areas with differing varieties through the draw-a-map task (Preston 1989). These responses are then aggregated using Geographic Information Systems (GIS), contrasting results between the two methods. Results are used to identify areas of salient dialectal features across New England, informing contemporary and future research into language change in a region considered as stable. Additionally, methodological concerns and advances are addressed.
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Yigit, Cisem. "Life Cycle Assessment In Ferrous Foundry Industry." Master's thesis, METU, 2013. http://etd.lib.metu.edu.tr/upload/12615559/index.pdf.
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Foundries are most widely facilities all around the world, producing high amounts of castings. In this study, environmental impact of metal foundries was investigated toward a life cycle assessment (LCA) goal. Studies were conducted in two foundry plants in order to collect the inventory data. The difference between the plants regarding their processes was the application of secondary sand reclamation (SSR) in Plant 2. Application of SSR is indicated as a
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Zerdin, Katherine. "The photodynamic effect on micro-organisms found on packaging materials." Thesis, View thesis, 2008. http://handle.uws.edu.au:8081/1959.7/38634.
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Many types of foods are sterilised and packaged aseptically to maximise their shelf life and ensure that they are safe for consumption. However, if even a few micro-organisms survive these treatments, the quality and/or safety of the food can be seriously compromised. Therefore, packaging materials that can actively participate in the process of inactivating micro-organisms have a potentially important role in protecting the quality and safety of packaged foods. The aim of this project is to explore the effectiveness of the photodynamic effect as a method of inactivating micro-organisms on the surface of packaging materials.
Photodynamic action occurs when a photosensitiser molecule absorbs light in the presence of oxygen, leading to the formation of reactive oxygen species such as singlet oxygen, superoxide radicals, or other free radicals; these species are known to inactivate cells. Medical uses of photodynamic action have been studied extensively, usually in applications where the reactive oxygen species are produced intracellularly. However, very little research has been conducted to investigate the efficacy of extra-cellularly generated reactive oxygen species on the viability of micro-organisms, and accordingly this research project investigated the possibility that this approach might be used for inactivating micro-organisms on packaging materials. The results of this study indicate that singlet oxygen may be produced at the surface of polymer films that contain selected photosensitisers, resulting in the oxidation of known singlet-oxygen acceptors to form endoperoxides. This provides evidence that singlet-oxygen mediated reactions can occur at the surface of a sensitising film. It is likely that cell destruction is caused by singlet-oxygen, rather than involving other activated species.
It was further shown that the photodynamically generated singlet-oxygen can inactivate micro-organisms (extra-cellularly) on the surface of a polymeric material. The study included examples from each genus of micro-organisms that are of concern to the food and packaging industry, including: Gram-negative bacteria (Escherichia coli); Gram-positive bacteria (Bacillus cereus), both vegetative cells and endospores; yeast (Saccharomyces cerevisiae), and mould (Fusarium oxysporium.) Results indicate that the photodynamic effect causes a substantial reduction in viable cell numbers for vegetative cells and spores (both bacterial and fungal) that have been inoculated onto a plastic surface containing the photosensitiser, anthraquinone,. The results show that an increase in the amount of reactive oxygen species produced by photodynamic action increases the inactivation rate of the micro-organisms. The
micro-organisms investigated were susceptible to photodynamic action to varying extents.
In conclusion, the results demonstrate that control of microbial populations on the surface of polymeric films (used in food packaging) is achievable using photodynamic action produced from polymers, based on the reported amounts of micro-organisms found on food packaging materials.
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Zerdin, Katherine. "The photodynamic effect on micro-organisms found on packaging materials." View thesis, 2008. http://handle.uws.edu.au:8081/1959.7/38634.
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Thesis (M.S. (Hons.))-- University of Western Sydney, 2008.<br>A thesis submitted to the University of Western Sydney in fulfilment of the requirements for the degree of Masters of Science (Honours), School of Natural Sciences, College of Health and Science. Includes bibliography.
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Ripoll, Vera Tomás V. "Miocardiopatía hipertrófica: estudio de la correlación genotipo-fenotipo en una población insular portadora de una idéntica mutación en el gen TNNT2." Doctoral thesis, Universitat de les Illes Balears, 2014. http://hdl.handle.net/10803/145472.
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La MCH es una de las enfermedades cardíacas hereditarias más comunes. La complejidad clínica que caracteriza a la MCH tiene su base en su heterogeneidad genética. Tras varios años de investigación, la identificación de mutaciones en 13 genes que codifican proteínas del sarcómero ha llevado a la definición de la MCH primaria como una enfermedad del sarcómero.
Las mutaciones en los genes MYBPC3 y MYH7 están involucrados en la génesis de la enfermedad en aproximadamente la mitad de los pacientes índice con MCH, mientras que las mutaciones en los genes TNNT2, TNNI3, TPM1, ACTC, MYL2 y MYL3 suponen entre un 1 a un 5% de los casos.
Dada la dificultad de predecir el riesgo de eventos adversos, como la MS, a partir de los datos clínicos, la investigación genética ha perseguido desde el principio determinar la relación entre el gen mutado o el tipo de mutación y la evolución de la enfermedad. Una correlación entre el genotipo y el fenotipo bien demostrada tendría implicaciones muy importantes para el tratamiento y la prevención de los eventos adversos en estos pacientes. Así en último término, los estudios moleculares y su correlación genotipo-fenotipo podrían ser herramientas útiles para ayudar al cardiólogo a tomar decisiones sobre los tratamientos a aplicar y el seguimiento individualizado de afectados y portadores asintomáticos.
A pesar de los avances en el campo de la Genética, en la actualidad no hay consenso definitivo sobre el grado de determinismo asignable a las mutaciones conocidas en los diferentes genes. Por tanto, son necesarios estudios poblacionales con grandes series de pacientes a partir de los cuales poder establecer conclusiones definitivas sobre la relación genotipo-fenotipo.
La información sobre genotipo-fenotipo y pronóstico de las diferentes mutaciones en el gen de la troponina T (TNNT2) es escasa y en ocasiones contradictoria, por su baja prevalencia (3-5%) en las series publicadas. Clásicamente se han relacionado las mutaciones en TNNT2 con un alto riesgo de muerte súbita (MS) en jóvenes con HVI leve.
En consonancia con todo lo expuesto nos propusimos los objetivos de esta Tesis Doctoral:
1. Estudiar la penetrancia de la miocardiopatía hipertrófica en 9 familias portadoras de una idéntica mutación en el gen TNNT2.
2. Describir las variables morfológicas, clínicas y valor pronóstico de los pacientes portadores de la mutación Arg92Gln en el gen TNNT2 en nuestra serie, y comparación con las publicadas.
3. Comparar las características clínicas y pronósticas de esta población con una cohorte de pacientes con MCH no portadores de esta mutación, especialmente pacientes con otras mutaciones identificadas en TNNT2, otras mutaciones en genes sarcoméricos y pacientes con mutación no identificada.
4. Evaluar la prevalencia de mutaciones en genes sarcoméricos en pacientes con MCH de nuestra comunidad.
5. Demostrar un efecto fundador de la mutación Arg92Gln en la población de estudio.
Para ello, desde noviembre del 2007 hasta febrero 2012 se evaluan 210 pacientes consecutivos no emparentados con diagnóstico de MCH. En todos los probandos se realiza estudio cardiológico completo, y se recoge muestra sanguínea para análisis genético. A los familiares de primer grado se les ofrece la realización de screening familiar consistente en evaluación cardiológica y genética (si hallazgo de mutación en el probando).
En todos los pacientes se recogen una serie de variables en relación a la caracterización del fenotipo. La penetrancia de la enfermedad la determinamos en base a los criterios eléctricos y ecocardiográficos.
En 8 probandos se identificó una idéntica mutación de tipo missense en heterocigosis en el gen TNNT2: Arg92Gln, localizada en el exón 9. Posteriormente se analizó la presencia de dicha mutación en los familiares, y se buscó un posible efecto fundador.
Se realiza un exhaustivo análisis de resultados en cuanto a las variables clínicas y genéticas analizadas, prestando especial atención a los marcadores de mal pronóstico y/o muerte súbita en estos pacientes.
Nuestro estudio concluye lo siguiente:
1. Las mutaciones en el gen de la troponina T son responsables de un 11.4% de casos de MCH en nuestra población insular, muy superior al de otras series.
2. El origen insular de la población de estudio, y la endogamia asociada habitualmente a este tipo de poblaciones, ha influido probablemente en la alta prevalencia de estas mutaciones.
3. Se constata un efecto fundador causal de los numerosos casos de MCH por la mutación Arg92Gln, localizada geográficamente en el noroeste de Mallorca, que no explica todos los casos, pero sí la mayoría.
4. La mutación TNNT2 Arg92Gln se asocia a miocardiopatía de desarrollo precoz, a menores edades que el resto de mutaciones. La probabilidad que el 50% de los portadores expresen el fenotipo se alcanza a los 37 años de edad.
5. La MCH por mutación TNNT2 Arg92Gln se caracteriza por una alta penetrancia, un alto riesgo de MS en jóvenes, en la mayoría como 1ª manifestación de la enfermedad, precisando el 38% implante de DAI como prevención primaria, con casos de MCH con hipertrofia sólo leve o moderada o en muchos otros casos con MCD al diagnóstico.
6. La mutación Arg92Gln produce alta frecuencia de fenotipo mixto: MCH con hipertrofia leve o moderada, y/o MCD, incluso dentro de la misma familia y a edades similares. Asimismo presentan disfunción sistólica en un porcentaje elevado (45%).
7. Los sujetos índice portadores de la mutación TNNT2 Arg92Gln presentan un perfil de riesgo significativamente peor comparado con el resto de pacientes con MCH y otras mutaciones o mutación no identificada. Existe una peor supervivencia libre de muerte cardiovascular asociada a esta mutación. La supervivencia media es de 54 años. A los 50 años la probabilidad de supervivencia es del 50%.
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Bangara, Athena. "The effect of institutions, organisational governance and managerial intentionality on the internationalisation of smaller Indian firms." Monash University. Faculty of Business and Economics. Department of Management, 2008. http://arrow.monash.edu.au/hdl/1959.1/68403.
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Emerging economies and the behaviour of firms domiciled in these markets is beginning to develop as a research area; yet little empirical work exists (Bruton, Ahlstrom, & Obloj, 2008; Hoskisson, Eden, Lau, & Wright, 2000; Meyer & Peng, 2005; Peng, Wang, & Jiang, 2008; Wright, Filatotchev, Hoskisson, & Peng, 2005). An extensive and critical review of the literature revealed that there was limited research that focused on the internationalisation of emerging economy firms to other emerging and developed economies. In order to address this clear gap in our understanding, the broad research problem that this thesis sets out to investigate is ‘how do institutions, organisational governance and managerial intentionality effect the internationalisation of smaller Indian firms’? It is argued that in order for research in strategy to make a lasting contribution, there is a need to contemplate whether the theories and methodologies developed in primarily mature and developed economies are applicable to the emerging economy context (Wright et al., 2005). In addressing this concern, this study draws on institutional theory, transaction cost theory, the resource-based view and aspects of the organisational capabilities perspective in order to understand the internationalisation of smaller Indian firms. In particular, the aim of this research was to understand the effect of institutions (Research Question One), organisational governance (Research Question Two) and the moderating effect of managerial intentionality (Research Question Three) on the internationalisation of smaller Indian firms. India was chosen as the context for the study due to its rapid growth in recent years which places it among the four big emerging economies of the world (Wilson & Purushothaman, 2003). The relatively recent liberalisation of the Indian economy in 1991 provides an interesting context within which to study the internationalisation behaviour of firms. Prior to its liberalisation India adopted what was known as an inward-focused, socialist-style, economic framework (Wilson & Keim, 2006). The liberalisation of the Indian economy has increased the country’s trade linkages with other emerging and developed countries, yet little research has been conducted on the internationalisation of Indian firms (Peng et al., 2008; Wright et al., 2005). Further, India’s linguistic distance but geographic closeness to emerging markets, yet western Commonwealth past and geographic distance to developed markets makes it a unique context. The research methodology adopted in this study entailed a qualitative design conducted through multiple case studies. The case study firms comprised four smaller manufacturing and four smaller service firms. Cases for the study were selected theoretically (Eisenhardt, 1989) using intensity sampling, snowball sampling, criterion sampling and opportunistic sampling techniques (Patton, 1990). To determine the size of the firms, the definition proposed by the Government of India was used. One key growth region in India was chosen due to the institutional diversity in India. Bangalore was chosen as it is considered a high growth region of the country that is well reputed for its service sector, as well as a competitive manufacturing sector (Ahya, Xie, Roach, Sheth, & Yam, 2006). The adoption of a multiple case study design facilitated an aggregated cross-case analysis. The data was collected through in-depth, semi-structured interviews with senior management in the selected case study firms. In addition, documentary evidence was collected through newspaper articles, information from trade journals and information from the company websites. The interviews were guided by an interview protocol and a case study database was created for each firm in order to increase the reliability and validity of the data. The data was coded using NVivo (version 7) and analysed using the ‘template approach’ (Crabtree & Miller, 1999). To date, literature originating out of mature markets has regarded institutions as background information due to the stability and maturity of institutions in these markets (Ingram & Silverman, 2002). However, when studied in an emerging market context, the role of institutions is argued to be pushed to the forefront of strategy research due to its relative underdevelopment (Meyer & Peng, 2005). This study used Scott’s (1995) three institutional pillars (regulative, normative and cognitive) to gain an institution-based view of the business strategies pursued by the smaller Indian firms (Peng et al., 2008). The findings highlighted regulatory institutional influences at the home country, host country and trade policy levels. The findings from this study shed light on the notion of institutional entrepreneurship, thereby extending institutional theory to take into account the strategic behaviour of firms. The findings further emphasised the need to gain legitimacy in international markets as a means to gain access to resources and overcome the liabilities of foreignness and newness. In doing so, the findings from this study extended Mathews’ (2006) ‘linkage, leverage and learning’ strategy to a ‘linkage, leverage, learning and legitimising’ strategy. Next, the findings from Research Question One extended the U-Model of internationalisation to highlight the importance of domestic market experience when gained in an institutionally complex market such as India. Finally, the findings highlighted the interaction between the path-dependent experience of the founders and the various dimensions of their managerial intentionality in managing the institutional influences on the firm. In studying organisational governance decisions (Research Question Two), transaction cost theory was used as the key conceptual perspective. This study used Williamson’s (1975) governance continuum to understand the organisational governance decisions of smaller Indian firms. Interestingly, the findings emphasised a move away from the narrow comparative-efficiency framework developed by Williamson (1975), towards a more eclectic understanding of the effect of transaction costs. The findings highlighted the choice of governance modes not as discrete designs, but as those that overlap as a result of being influenced by institutions, the experience of the firm with a particular mode, the propensity to trust, the constraints on firm behaviour, the managerial intentionality of the founders and the need to gain local knowledge from network partners. In adopting this broader perspective, the findings addressed the call by Madhok (1997) to understand the choice of governance modes from more than a cost minimisation perspective. Hutzschenreuter, Pedersen and Volberda (2007) suggested that the role of managerial discretion to date is downplayed in existing IB literature and hence called for research to focus on the role of managerial intent in the strategies of established multinationals rather than on the process of ‘becoming a multinational’. Research Question Three highlighted the moderating effect of managerial intentionality in managing the institutional influences and governance decisions of the firm. This study extended Hutzschenreuter et al.’s (2007) conceptualisation of managerial intentionality by emphasising the resilience as well as the reluctance of the founders (due to past experiences) as important in the emerging economy context. This study has practical implications for the case study firms as well as for potential entrants into India. Firstly, for the case study firms it is important to develop clear internationalisation strategies (as opposed to a reactive approach) due to the increasing competition both locally and internationally. Second, for the manufacturing firms, it is important to move beyond their pure low cost advantage. Partnering with other companies to leverage their resources and capabilities in international markets is one possibility. Third, for these firms to remain globally competitive, the sourcing of international talent is likely to increase their legitimacy and reduce their liability of foreignness. Finally, the continued liberalisation of the Indian economy has made it an attractive destination for foreign firms. While the case study companies have recognised the opportunities overseas, they should not ignore their domestic market where they enjoy a ‘home court advantage’. For potential entrants into India, it is important to recognise the potential competitive advantage that local incumbents have with regard to the environment. Second, foreign firms entering India and competing with smaller players need to understand the subtleties of the market and tailor their strategies to meet local needs. Finally, while this study has made contributions to the field, the findings must be interpreted in light of the limitations of the study. First, this study focused on one key big emerging market; India. Further, within India only one key region was examined. The findings reflect the business strategies by firms domiciled in Bangalore. Hence future studies could extend this research to other emerging markets and other regions of India to gain a more detailed perspective. Second, given the qualitative nature of the study, only analytical generalisations can be made. However, these insights can provide a basis for future researchers to develop quantitative measures to test the inferences drawn. Finally, this study was cross sectional in nature. In order to gain a more detailed analysis on the effect of institutions, future researchers may consider a longitudinal design to capture the institutional transitions over time.
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Brauckhoff, Heiko. "The effects of globalization on strategy formulation in the German foundry industry : an empirical study." Thesis, University of Surrey, 2012. http://epubs.surrey.ac.uk/810916/.
Full textAbstract:
Strategy formulation is most critical in times of change and has long been a topic of great interest in the field of strategic management, because the effectiveness of formulating the right strategies determines whether companies are able to change and adapt to their environment, and therefore whether they are ultimately successful. Within the ongoing process of globalization, SMEs also recognize that the competition for market share is global, and that participating in the global economy is no longer a choice but a necessity. Therefore, globalization exposes SMEs to numerous strategic and organizational challenges emanating from a dramatic increase in diversity, complexity, and uncertainty - external as well as internal to the company. The thesis aims to provide an answer to the following research question: "Are there any effects of globalization on strategy formulation based on resource-orientation and/or market-orientation in the German foundry industry?" The thesis follows a positivistic approach because in the literature a large quantity of data is available about strategy and globalization, which allows the researcher to generate research questions that are tested mainly by the survey. Therefore, the author has used a deductive and quantitative approach, because the theory of strategy making, such as the REV and the MBV, is used deductively. We have three significant practical implications of this research. First, strategy formulation is a blend of resource-orientation and market-orientation. Second, the MBV elements of strategy are overall more significant than the REV elements of strategy. Especially the size of the firm seems to be important regarding the strategic orientation. Third, who makes strategy determines the firms response in times of globalization. Overall, the findings join proposals to combine both the market-based and resource-based view when formulating strategies. When employed as blend of these two approaches, it encourages managers to think and act in ways that are more entrepreneurial and creative. Following these suggestions can substantially influence the strategy formulation and improve the performance.
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Bolinder, Richard. "Atmospheric Radiation Effects Study on Avionics : An Analysis of NFF Errors." Thesis, Linköpings universitet, Programvara och system, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-96726.
Full textAbstract:
No fault found (NFF) errors, i.e. errors which origin has not been established, irregularly occur in electronic devices. The actual cause of such errors varies but one, possibly more prominent, source for these soft errors is atmospheric radiation. The overarching aim of this thesis is to demonstrate: 1) the importance of keeping the atmospheric radiation environment in mind when designing robust airborne systems, 2) how to take this environment into consideration when applying mitigation techniques which may drastically reduce the risk of SEEs (Single Event Effects) which can cause NFF errors. To achieve these goals, Part 1 of this thesis describes how cosmic rays affect electronics (i.e. what kind of errors may be induced), which types of devices are susceptible to radiation, and why this subject is of extra importance for airborne systems. In addition, soft error mitigation techniques, which may be applied at different design levels to reduce the soft error rate (SER) or the impact of soft errors, are also presented. The aim is further corroborated by Part 2. Five subsystems of a modern aircraft are studied and real examples of failures potentially induced by atmospheric radiation are presented. For each of the five systems, all errors that have been reported for these (in the past few years) have been studied, and the number of errors found to be potentially induced by cosmic radiation has been listed and compared to number of expected soft errors based on calculations and previous experimental tests.
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Javidani, Mousa. "Effect of Cu, Mg and Fe on solidification processing and microstructure evolution of Al-7Si based foundry alloys." Doctoral thesis, Université Laval, 2015. http://hdl.handle.net/20.500.11794/26146.
Full textAbstract:
Au cours de la dernière décennie, les alliages de fonderie Al-Si ont été utilisés de plus en plus comme une alternative appropriée à la fonte dans la fabrication de composants de moteurs (par exemple les culasses). Les objectifs du projet étaient d'étudier l'effet des éléments tels que le cuivre, le magnésium et le fer sur les défauts de solidification, et sur l'évolution des phases poste-eutectiques les alliages de fonderie Al-Si. Tout d’abord, les travaux antérieurs sont soigneusement examinés afin de mieux comprendre les charges de fatigue thermomécanique, les caractéristiques, les exigences et les matériaux applicables dans les composantes du moteur. Par la suite, les défauts de solidification (tendance de fissuration à chaud (HTS) et microporosité) des alliages à base d’Al-Si ont été évalués. En augmentant la teneur en Cu et en Fe des alliages, la valeur de HTS et de microporosité ont été augmentées. Les indices théoriques de fissuration à chaud ont été simulés avec un modèle de microségrégation multiphasique avec rétrodiffusion dans la phase primaire «multiphase back diffusion model». La corrélation obtenue entre les résultats expérimentaux (HTS) et les résultats simulés est excellente. L’effet de la composition chimique (Cu, Mg et Fe contenu) dans les alliages Al-Si sur l'évolution de la microstructure ont donc été étudiées. Les microstructures à l'état de coulée et à l'état de traitement thermique de mise en solution (SHT) ont été évaluées par les microscopies optique/électronique. Deux intermétalliques contenant du Mg (Q-Al5Cu2Mg8Si6, π-Al8FeMg3Si6) qui apparaissent avec une couleur grise sous le microscope optique ont été discriminés par des attaques chimiques que nous avons développées. L’analyse calorimétrique différentielle à balayage (DSC) a été utilisée pour examiner les transformations de phase survenant au cours du processus de chauffage et de refroidissement. Les calculs thermodynamiques ont été effectués pour évaluer la formation de la phase à l'état d'équilibre et hors-équilibre. Les résultats ont démontré que la séquence de solidification et la stabilité des intermétalliques contenant du Cu/Mg ont été fortement influencée par la composition chimique des alliages. La phase Q-Al5Cu2Mg8Si6 a été solidifiée soit à la même température ou plus tôt que la phase θ-Al2Cu en fonction de la teneur en Cu de l'alliage. Par ailleurs, les phases Q-Al5Cu2Mg8Si6 et π-Al8FeMg3Si6 qui étaient solubles à 505℃ dans l'alliage Al-7Si-1.5Cu-0.4mg, sont restées presque intactes dans l'alliage Al-7Si-1.5Cu-0.8mg wt.-%. Bien que l’intermétallique-AlCuFe a été à peine observé dans la microstructure de coulée, la réaction entre la phase primiare α-Al avec la phase β-Al5FeSi a causé la formation de la phase N-Al7Cu2Fe au cours de la mise en solution. La transformation de phase à l'état solide de la phase β-Al5FeSi à la phase N-Al7Cu2Fe a également été étudiée.<br>Over the past decade, Al-Si based foundry alloys have increasingly been used as a suitable alternative for cast iron in the fabrication of engine components. This project was aimed to study the effect of Cu, Mg and Fe elements on solidification defects (hot rearing tendency and microporosity), and on evolution of post eutectic phases in the Al-7Si (wt.-%) based alloys. Initially, the previous works and the most pertinent literatures were thoroughly reviewed to elaborate the thermo-mechanical fatigue loads, characteristics, requirements and materials applicable in engine components (mainly cylinder-head). Subsequently, the solidification defects of the Al-Si based alloys were evaluated. By increasing Cu and Fe content of the alloys, the hot tearing sensitivity and the microporosity content of the alloys were both enhanced. Multiphase back diffusion model was utilized to simulate the theoretical hot tearing indices. A very good correlation was obtained between the experimental and the theoretical hot tearing indices. Effect of the chemistry (Cu, Mg and Fe content) on microstructure evolution of the Al-Si foundry alloys was consequently studied. As-cast and solution heat treated (SHT) microstructures of the alloys were evaluated by optical- and electron-microscopy. Two etchants were developed to discriminate the Mg-bearing intermetallics (Q-Al5Cu2Mg8Si6, π- Al8FeMg3Si6) under optical microscope. Differential scanning calorimetry (DSC) was utilized to examine the phase transformations occurring during heating/cooling process. Thermodynamic computations were carried out to assess the phase formation in the equilibrium/non-equilibrium conditions. According to the predicted/experimental results, the solidification sequence and the stability of Cu/Mg bearing intermetallics are strongly influenced by the chemistry of the alloys. Q-Al5Cu2Mg8Si6 phase was solidified either at the same temperature or earlier than θ-Al2Cu phase depending the Cu content of the alloy. Moreover, Q-Al5Cu2Mg8Si6 and π- Al8FeMg3Si6 which were soluble at 505℃ in the alloy Al-7Si-1.5Cu-0.4Mg, remained almost intact in the alloy Al-7Si-1.5Cu-0.8Mg wt.-%. Tough the AlCuFe- intermetallic was barely observed in the as-cast microstructure, the reaction of α-Al with the β-Al5FeSi phase caused the formation of the N-Al7Cu2Fe phase during SHT. The solid state phase transformation (precipitation temperature and mechanism) of β-Al5FeSi to the N-Al7Cu2Fe phase was also investigated.
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Kapp, Anine A. C. "Evaluation of temperature variances found with integral reefer containers during shipment of Japanese plums (Prunus salicina Lindl.) at dual and single temperature." Thesis, Stellenbosch : Stellenbosch University, 2008. http://hdl.handle.net/10019.1/21447.
Full textAbstract:
Thesis (MScAgric)--Stellenbosch University, 2008.<br>ENGLISH ABSTRACT: Stone fruit is susceptible to chilling injury and intermittent warming has been shown to
alleviate chilling injury during cold storage. A dual temperature storage regime was
developed in South Africa for plums based on the principles of intermittent warming. The
regime consists of an initial period at -0.5°C, a variable duration warming period at 7.5°C,
followed by -0.5°C. Refrigerated integral containers were designed to maintain product
temperature and not to reduce product temperature, per se. Considering that dual
temperature shipment requires significant refrigeration and effective distribution of cool air to
remove sensible- and respiratory heat, the capacity of integral containers to ship plums
successfully at dual temperature is questioned.
The objectives of this study were, firstly, to analyse pulp temperature data and possibly
identify different temperature zones within containers shipping plums at dual temperature.
Secondly, to understand the underlying processes differentiating the temperature zones and
thirdly, to determine the effect of container performance on fruit quality.
Three processes were identified as important characteristics of pulp temperature data sets
recorded during dual temperature shipping, namely cooling down, heating up and over
heating in the container. The order of importance differed according to the cultivar shipped
and the container’s performance. Three temperature zones were identified in dual
temperature containers, where the average pulp temperature, time to heat up and time to
cool down for each temperature zone increased along the length, across the width from the
left to the right and up the container system. The variable temperature conditions were
possibly due to a variation in delivery air temperature, poor airflow and the effect of increased
respiration and, therefore, production of vital heat by the fruit. The cooling down process was
identified as the most important process discriminating the temperature zones.
With the exception of ‘Fortune’, variable temperature conditions found within integral
containers shipping plums at dual temperature had a significant influence on the fruit
firmness post-shipment, where deterioration levels increased from the front to the door end
of the container due to an increase in pulp temperature. However, it was also shown that fruit
firmness prior to shipment could have a determining effect on differences found. It could not be proven that variable temperature conditions resulted in significantly higher levels of
internal defects within the integral container.
Temperature zones could not be identified within refrigerated integral containers shipping
plums at single temperature, suggesting that the containers are able to maintain the
temperature well throughout the container area.
A constant 2°C storage temperature could possibly replace the commercial dual temperature
regime in the case of ‘Pioneer’ plums due to improved fruit firmness, similar colour
development to the control and less sensible heat produced in the container resulting in a
more stable container environment. However, unacceptably high levels of shrivel and internal
browning were found.<br>AFRIKAANSE OPSOMMING: Steenvrugte is vatbaar vir koueskade en dit is bewys dat periodieke verwarming gedurende
koelopberging koueskade kan verlig. Die dubbeltemperatuur opbergingsregime is in Suid-
Afrika ontwikkel vir pruime en is gebaseer op die beginsels van periodieke verwarming. Die
regime bestaan uit ‘n inisiële periode by -0.5°C, ‘n variërende periode by 7.5°C, gevolg deur
-0.5°C. Verkoelde integrale houers is ontwerp om produktemperature te handhaaf en nie
soseer om produktemperatuur te verlaag nie. Die kapasiteit van integrale houers om pruime
suksesvol teen dubbeltemperatuur te verskeep word dus bevraagteken, in ag geneem dat
dubbeltemperatuurverskeping betekenisvolle verkoeling en effektiewe verspreiding van koue
lug vereis om die waarneembare- en respiratoriese hitte te verwyder.
Die doelwitte van die studie was eerstens om die pulptemperatuurdata te analiseer en
moontlik verskillende temperatuursones binne houers wat pruime teen dubbeltemperatuur
verskeep te identifiseer. Tweedens, om die onderliggende prosesse wat die
temperatuursones van mekaar onderskei te verstaan, en derdens om die effek van die houer
se werkverrigting op vrugkwaliteit te bepaal.
Drie prosesse is geïdentifiseer as belangrike eienskappe van pulptemperatuur datastelle
aangeteken gedurende dubbeltemperatuurverskeping, naamlik afkoeling, opwarming en
oorverhitting wat binne die houer plaasvind. Die volgorde van belangrikheid het gevarieer
afhangende van die kultivar verskeep en die houer se werkverrigting. Drie temperatuursones
is geïdentifiseer binne integrale houers wat pruime teen dubbeltemperatuur verskeep, waar
die gemiddelde pulptemperatuur, die opwarmingstyd en die afkoelingstyd vir elke
temperatuursone in die lengte, oor die wydte van links na regs en van onder na bo in die
houersisteem toegeneem het. Die variërende temperatuur toestande kan moontlik toegeskryf
word aan ‘n variasie in leweringstemperatuur, swak lugvloei en die effek van toenemende
respirasie, en dus die produksie van hitte vrygestel deur die vrugte. Die afkoelingsproses is
geïdentifiseer as die belangrikste proses wat die temperatuursones van mekaar onderskei.
Behalwe in die geval van ‘Fortune, het variërende temperatuurtoestande in integrale houers
wat pruime teen dubbeltemperatuur verskeep ‘n betekenisvolle invloed op die vrugfermheid
na verskeping gehad, waar vrugveroudering toegeneem het van voor in die houer na die
deur van die houer as gevolg van ‘n toename in pulptemperatuur. Daar is egter bewys dat die vrugfermheid voor verskeping ook ‘n bepalende effek kon hê op die fermheidsverskille.
Dit kon nie bewys word dat die variërende temperatuurtoestande betekenisvol hoër vlakke
van interne defekte binne die integrale houer veroorsaak het nie.
Temperatuursones kon nie geïdentifiseer word binne verkoelde integrale houers wat pruime
teen enkeltemperatuur verskeep het nie, wat dus impliseer dat die houers daartoe instaat is
om temperatuur goed te onderhou binne die houer.
‘n Konstante 2°C opbergingstemperatuur kan moontlik die kommersiële
dubbeltemperatuurregime vervang in die geval van ‘Pioneer’ pruime as gevolg van
verbeterde vrugfermheid, soortgelyke kleurontwikkeling as die dubbeltemperatuurregime en
minder hitte geproduseer binne die houer deur die pruime, wat ‘n meer stabiele
houeromgewing veroorsaak. Onaanvaarbare hoë vlakke van verrimpeling en interne
verbruining is egter gevind.
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Finlay, Fleur. "Evidence for a retrieval strategy disruption interpretation of the inhibition effect found in studies of collaborative recall." Thesis, Lancaster University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.250018.
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Butler, Reece. "Effect of Heavy Metals Found in Flue Gas on Growth and Lipid Accumulation for Green Algae Scenedesmus obliquus." DigitalCommons@USU, 2011. https://digitalcommons.usu.edu/etd/1159.
Full textAbstract:
This study evaluated the effect of several heavy metals that are present in flue gases on the algae, focusing on the growth and accumulation of lipids in the algae that can be converted to biodiesel. Concentrations for the heavy metals were calculated based on literature and assumptions. Metals were tested individually first at the highest concentrations that might be present (reference concentrations). The metals and their reference concentrations were: arsenic at 1.56 mg/L, cadmium at 0.3 mg/L, chromium at 2.6 mg/L, cobalt at 0.32 mg/L, copper at 2.62 mg/L, lead at 1.09 mg/L, nickel at 5.08 mg/L, mercury at 0.2 mg/L, selenium at 0.2 mg/L, and zinc at 8.8 mg/L. At these concentrations, most of the metals had a negative effect on the growth and lipid content of the algae. All of the metals were then tested at lower concentrations. At 1/20 the reference concentrations, the metals enhanced growth as well as lipid accumulation in the algae. At higher concentrations there was a negative effect.
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Larsson, Emelie, and Johan Groening. "Effects of outsourcing transactional processes : A multiple cases study of Swedish SMEs on risks found within the internal control." Thesis, Karlstads universitet, Handelshögskolan (from 2013), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-67984.
Full textAbstract:
BackgroundToday’s competitive market forces companies to focus on their core processes. As a result, the number of outsourcing arrangements has grown and especially transactional processes outsourcing, which is clearly evident in Sweden. The lack of expertise and resources that characterizes SMEs makes outsourcing of transactional processes many times a necessity. However, little attention has been given the possible internal control risks associated with outsourcing (Christ et al. 2015). Moreover, frameworks such as the COSO-framework has also neglected to provide guidelines as to how companies should handle outsourcing arrangements. Although the COSO-framework argues that it can be applied to all companies, no matter the size, organizational structure or the choices management makes (COSO 2013). AimThe aim of this study is to identify and analyze internal control risks within Swedish SMEs when outsourcing transactional processes. Moreover, the study will try to provide recommendations to the COSO-framework about how outsourcing arrangements should be handled in order to maintain an effective internal control. MethodThe study uses a qualitative method where a multiple cases study is conducted. The study consists of three case companies where a total of four participants were interviewed through semi-structured interviews, where all participants has a managerial position at their respective company. ConclusionThe findings within the study indicates that outsourcing transactional processes has made the case companies more effective. Moreover, the performance and relational risks identified within the case companies align with previous research where multiple risks were identified. The authors also highlights the possibility of a new risk when outsourcing transactional processes. Furthermore, the authors suggest that the COSO-framework should be modified such that the outsourcing company is a part of the control environment within companies.
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Bergström, Balder. "The Swedish payroll tax reduction for young workers : - A study of effects found using publicly available aggregated (macro) data." Thesis, Umeå universitet, Nationalekonomi, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-166606.
Full textAbstract:
In 2007, the Swedish payroll tax was reduced for youths in an attempt to suppress the perceived high unemployment among Swedish youths. The reform was rolled back later in 2016. For this period there is a rich supply of publicly available aggregated (macro) data. This thesis aims to examine: first, if the aggregated data is suitable for policy evaluation of the reform, and second, the effects of the reform introduction and repeal. This has been done by using both a conventional fixed effects model and a more unorthodox synthetic control method. Neither of the two methods could show any unbiased and consistent significant result of the treatment effects of the reform. Instead, the results of this thesis suggest that the publicly available aggregated data doesn’t contain enough information to evaluate such reforms.
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Mutingwende, Nhamo. "Identification of agricultural and industrial pollutants in the Kat River, Eastern Cape and their effect on agricultural products found along the river banks." Thesis, University of Fort Hare, 2015. http://hdl.handle.net/10353/d1020242.
Full textAbstract:
There is growing concern that commonly used Pharmaceuticals and Personal Care Products (PPCPs) and pesticides are entering and contaminating drinking water supplies. The use of targeted quantitation of PPCP has been well established but there is an emerging trend to also screen for and identify unexpected environmental pollutants. Chemicals like pesticides hormones and antibiotics are especially of interest because of proven endocrine disrupting effects and a possible development of bacterial resistance. Powerful screening methods are required to detect and quantify the presence of these compounds in our environment. PPCP encompass a wide range of pollutants, including Endocrine Disrupting Compounds (EDC), pesticides, hormones, antibiotics, drugs of abuse, x-ray contrast agents and drinking water disinfection by-products to name a few. In order to properly assess the effects of these compounds on our environment, it is necessary to accurately monitor their presence. The diversity of chemical properties of these compounds makes method development challenging. LC/MS/MS is able to analyse polar, semi-volatile, and thermally labile compounds covering a wide molecular weight range. The new AB SCIEX TripleTOF™5600 LC/MS/MS was used to profile environmental samples for unexpected pollutants, to identify and characterise the chemical composition and structure of the pollutants, and to quantify (based on intensity) the concentration in collected water samples. Liquid Chromatography coupled to tandem Mass Spectrometry (LCMS/ MS) is able to analyse polar, semi-volatile, and thermally labile compounds covering a wide molecular weight range, such as pesticides, antibiotics, drugs of abuse, x-ray contrast agents, drinking water disinfection by-products etc. More recently there is a growing interest from environmental researchers to also screen for and identify non-targeted compounds in environmental samples, including metabolites and degradates, but also completely unexpected pollutants. The new AB SCIEX TripleTOF™5600 LC/MS/MS system is capable of performing highly sensitive and fast MS scanning experiments to search for unknown molecular ions while also performing selective and characteristic MS/MS scanning for further compound identification and, therefore, is the instrument of choice for this challenging task. General unknown screening workflows do not use a target analyte list and compound detection is not based on any prior knowledge, including retention times and information on possible molecular and fragment ions. Therefore, acquired chromatograms are very rich in information and can easily contain thousands of ions from both any compounds present in the sample as well as from the sample matrix itself. Thus, powerful software tools are needed to explore such data to identify the unexpected compound. Water samples were collected both upstream and downstream of two WWTPs (Seymour and Fort Beaufort) and were directly injected on the AB SCIEX TripleTOF™5600 LC/MS/MS after being filtered. 15 sample points along the Kat River, ranging from a point as close to the source as possible to a point just before it joins the Great Fish River were used. The samples collected from the source were used as the control in each of the experiments, the assumption being the closer you get to the source, the less contaminated the water would be for the analysis of pesticides. Points were selected where the Kat River crosses the R67 or on farms where the river was accessible using farm roads. Samples were collected from October 2013 to November 2014.The Peak view software and Analyst software were used in the analysis of PPCPs. The XIC Manager allows you to manage large lists of compounds and perform automatic extracted ion chromatogram (XIC) calculations and review results operations. The results were displayed in the chromatogram pane and the XIC table (see results). The results reported here in this thesis indicate that there is contamination in the Kat River water due to both pesticides and PPCPs. The results also indicate that the food products are also contaminated and hence both the Kat River agricultural produce and its water need to be closely monitored for both pesticide and PPCPs contaminants. Further studies to investigate the quantitative levels of pesticides and PPCPs in the Kat river water to determine if the concentration levels of the detected pesticides are below the reported Maximum Residues Limits will be explored in the future.
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Saltzwedel, Helge von [Verfasser], Marina [Akademischer Betreuer] Schäfer, Stefan [Akademischer Betreuer] Scheu, and Mark [Akademischer Betreuer] Maraun. "Genetic diversity of sexual and parthenogenetic soil living arthropods (Collembola) in Europe: colonization patterns, pre-glacial diversifications and founder effects : Genetic diversity of Collembola in Europe / Helge von Saltzwedel. Betreuer: Marina Schäfer. Gutachter: Stefan Scheu ; Mark Maraun." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2016. http://d-nb.info/1095884131/34.
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Lavoie, Monique V. "Characterisation of a conserved motif found within the Dlx cis-regulatory element URE2 and its effect on mouse URE2-lacZ activity in transgenic mice." Thesis, University of Ottawa (Canada), 2010. http://hdl.handle.net/10393/28433.
Full textAbstract:
The Distal-less-like genes, commonly referred to as Dlx genes, encode homeodomain transcription factors essential for the establishment of GABAergic interneurons in the ventral forebrain as well as their migration to the cortex. The cis-regulatory element URE2 (enhancer) is located upstream of Dlx1 and is thought to regulate the transcription of Dlx1 and/or Dlx2. The objective of this study was to examine a short conserved sequence within the URE2 element, corresponding to nucleotides 699-719, and to evaluate its contribution to URE2 activity in transgenic mouse forebrain. My results showed that a mutant version of the URE2 element, in which nucleotides 699-719 were modified, was active in the cortex and the ventricular zone of forebrain of the transgenic mice produced with the mutant enhancer, where Dlx1/Dlx2 are not usually expressed. This indicated a loss of binding by a protein with a transcriptional repressor function. Previous analyses suggested that mURE2nt699-719 would be a good candidate for a REST repressor binding site. However, we were not able to observe any transcriptional regulation by REST in co-transfection experiments performed in cultured cells. This, as well as revised bioinformatical information, led us to identify four new candidates possibly using mURE2nt699-719 as a binding site, namely the Nuclear- Factor-1 proteins: NFIA, NFIB, NFIC and NFIX. These genes are associated with transcriptional regulation, being repressors and/or activators of gene expression in the brain. We showed that NFIC was able to utilize the mURE2nt699-719 sequence to reduce the luciferase reporter expression in neuronal cells, which would explain the loss of repression in our transgenic mice at embryonic days E11.5 and E13.5. These preliminary results also allowed us to suggest that a heterodimer between NFIC/NFIB and NFIC/NFIX binds to the mURE2699-719 sequence at embryonic day E15.5 and postnatal day 0 (P0) of the transgenic mice since the mutated enhancer's activity seems to indicate a loss of an activator at those stages. These results suggest that these factors could possibly be required for the regulation of the Dlx genes by URE2. These results will also help clarify the role of URE2 by identifying transcription factors that contribute to the genetic program involved in the cellular organization of the developing forebrain in vertebrates.
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Giordano, Matteo. "Energy Savings Potential in Dual Smart Grid Solutions : Are there synergy effects to be found using a dual smart grid system for heat and electricity?" Thesis, KTH, Energiteknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-283129.
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Smart cities and eco-districts will shape a new city landscape in the upcoming years, making renewables the only source of energy. They have the potential to cut greenhouse gas emissions up to 99 %, reaching the ambitious energy and sustainability goals set by Europe and the rest of the world. Double smart grids is a 20th-century concept aiming at connecting the current main energy networks as(electrical and thermal) into a unique mesh. It enables the exchange of energy and new options for storage, flexibility, and reliability. The goal of this study is to show the potential energy savings captured by the implementation of a double smart grid on a district and city level, and to quantify energy savings on a European scale. The first chapter of this work aims to clarify the objective of a smart grid, how it is composed, and why it is called smart. It implies a complete understanding of the history of the two grids, digging on the district heating concept as well as the fundamental of an electrical grid. Moreover, an overview of the major energy needs that usually exist in a district has been presented, to demonstrate what a double smart grid should meet in terms of energy demands. Secondly, an exhaustive analysis has been carried out to point out the main technologies available on the market to meet these energy needs. It focuses on all major renewable heat sources and the upcoming technologies expected to help energy transition in reaching its ambitious goals. The same process is applied for the most mature renewable electricity sources, with a focus on decentralized and decentralized structures. Storage options and flexibility have been added at the list since their integration will drastically reduce energy production. This means that, before producing new energy, it is necessary to better consume the one already produced. It is always true that the greenest kWh is the one ever produced. Lastly, double smart grid synergies have been evaluated through an exhaustive analysis of a smart renewable energy scenario, that includes a complete integration of the double smart grid concept, in the first step, and a triple smart grid concept as full-cycle scenario (including green gas networks). Throughout the entire document, several project examples have been presented to complete the theoretical knowledge with concrete examples developed all over the world. Most of them have been developed by Dalkia Smart Building. The results show the necessity to boost innovation and pilot projects around double smart grids and in general smart energy systems, and it will require impressive efforts from government and private investors.
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Clewåker, Ottilia, Paulina Johansson, and Rebecka Rundqvist. "Firm founders adopted traits in their enterprises, and its effect on enterprise success in the different stages : A qualitative study that explores what traits are of significant value to adopt in birth, growth and maturity stages in an enterprise in Sweden." Thesis, Internationella Handelshögskolan, Högskolan i Jönköping, IHH, Företagsekonomi, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-44243.
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The number of enterprises has grown throughout the past decades, where previous research emphasizes that the difficulties of succeeding as a self-employer is a fact. Today’s society is evolving towards a competitive market of self-employment, where traits play a bigger role through the whole process. In this context, the distinct traits adopted by firm founders in birth, growth and maturity stages of an enterprise in Sweden, has not been thoroughly examined. Therefore, the authors aim to provide insight in what traits firm founders have adopted in the different stages through a retrospective perspective, and to what extent their traits have affected the success in each stage of the firm. This study collects qualitative data and adopts a comparative case study to identify what traits unite the firm founders. By conducting four semi-structured in-depth interviews, the authors identified a common trait in each stage of the enterprises amongst all participants, which were dedication (birth), energy (growth) and straight forward (maturity). Evidence showed that the common traits are specific managerial trait in birth stage, whereas leadership traits in growth stage and maturity stage. The study then elaborates on to what extent the adopted traits affect enterprise success in each stage, in which it is proven by the literature provided, that the specific traits do not lead to a particular success in the given stage.
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OBADIA, BAROGHEL SYLVIA. "Frittage de melanges al::(2)o::(3) + sio::(2) gel pour moules de fonderie : developpement des microstructures et deformation a chaud." Paris, ENMP, 1987. http://www.theses.fr/1987ENMP0079.
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Etude du frittage reactif de melanges prepares a partir de la silice colloidale et l'alumine alpha entrant dans la composition des moules. Influence du temps, de la temperature et de la composition initiale sur l'affaissement des moules carapaces de fonderies pour la coulee/solidification dirigee des aubes de turbine des reacteurs d'avions
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Leonard, Charles C. "Paul Renner and Futura: The Effects of Culture, Technology, and Social Continuity on the Design of Type for Printing." Digital Archive @ GSU, 2006. http://digitalarchive.gsu.edu/art_design_theses/2.
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This thesis reviews the circumstances that led to what Paul Renner called “the inflation of historicism,” places his response to that problem in the context of the Weimar Republic, details how the German attributes with which he began the project were displaced from the typeface that emerged in 1927, demonstrates that Futura belongs to a new category of serif-less roman fonts rooted in Arts and Crafts lettering, and considers why the specifically German aspects of the project have gone unrecognized for over seventy years. Renner’s writing is compared to ideas prevalent in early twentieth-century German cultural discourse, and Futura’s design process is placed in the context of Renner’s personal experience of Weimar’s social and economic crises. Objective measurements are employed to establish the relationship between drawings attributed to Renner and are used to compare features of Futura with other fonts of the period.
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Habgood, Angela Kate. "The effects of tissue-specific proteinase activated receptor-2 (PAR-2) ablation on remodelling events found in bone and cartilage, using a murine destabilisation of the medical meniscus (DMM) model." Thesis, University of Newcastle upon Tyne, 2017. http://hdl.handle.net/10443/3858.
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Osteoarthritis (OA) is a common musculoskeletal disease, associated with significant cost to the National Health Service (NHS) and physical consequences to the sufferer. It is known that cartilage degradation and subchondral sclerosis are hallmark features of OA. However, it is not known in which tissue pathological changes occur first. By identifying this, future therapeutics could be guided more accurately to maximise their benefit. This study has highlighted significant problems in generating a reliable and reproducible human‐derived model of cartilage catabolism using human mesenchymal stem cells (hMSCs). Generating such a model is important, as it will allow assessment of potential therapies in a physiologically relevant human model, and further work is needed in this area. However, one significant finding from this work was that the addition of matriptase to a cytokine stimulus enhanced proteoglycan and collagen degradation from cartilage discs and macro‐pellets. Matriptase is a serine proteinase, and is involved in cartilage catabolism through activation of pro‐MMPs and signaling via PAR‐2. These findings therefore support the role of matriptase in OA pathogenesis, specifically cartilage catabolism. Proteinase‐activated receptor‐2 (PAR‐2) is known to be involved in OA pathogenesis, with global ablation of this receptor preventing abnormal remodelling events in the cartilage and subchondral bone. In this study, tissue‐specific ablation of PAR‐2 revealed that loss of PAR‐2 conferred its primary beneficial effect in the bone by preventing subchondral sclerosis. The debate about whether cartilage or bone changes occur first in OA remains controversial, but it was apparent from various time‐course studies that bone changes occurred first, followed by cartilage catabolism during OA progression. However, in this study it was also evident that cartilage damage could occur independently of subchondral sclerosis, which is in opposition to the long standing view that subchondral sclerosis is a prerequisite for cartilage damage to occur. Thus, this study highlights that targeting either the cartilage or bone may be beneficial for therapies, although for ease of use, targeting the bone may be more clinically useful. Furthermore the importance of PAR‐2 expressed on chondrocytes in the development and maturation of osteophytes was evident in this study.
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Bronoske, Bruce Leonard. "A comparative study of the self-revelation of Jesus found in the canonical New Testament and the Jesus of the Qur'an, and the effect a Muslim seeker's understanding of Jesus has upon their decision to convert to Christianity." Theological Research Exchange Network (TREN), access this title online, 2005. http://www.tren.com/search.cfm?p106-0001.
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Magnusson, Victor. "Cut off cross-border data flow and international investment law. : A legal analysis of a restriction with an effect equivalent of a ban on cross-border data flow and the fair and equitable treatment standard found in bilateral investment treaties." Thesis, Uppsala universitet, Juridiska institutionen, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-443840.
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In the world we live in today, the international trade and economy is becoming more and more dependent on data. Data that can be transferred across borders and during the last couple of years there is an observable trend that the cross-border data flows is increasing. The increase of the cross-border data flows is a result of the vast boom in the global digitalization. Businesses and enterprises can use the data accessible in multiple kinds of ways, follow and keep control of production chains, follow the demand of consumers, and make alterations to the products following the requests of the consumers. This is improving the efficiency and productivity of the businesses. The free flow of data across borders does not only have positive effect for the businesses, but also from a larger perspective, it also contributes to the welfare of countries, and provide new possibilities and opportunities. Despite the fact that the free flow of data has its great effects on both businesses and the welfare of states, states are imposing restrictions on cross-border data flows. The restrictions in place are of deferent kinds, some makes it mandatory to store or process data, while other restrictions are harsher and could provide a ban or cut off on cross-border data flow. In the legal system of international investment law, the fair and equitable treatment standard is a standard found in treaties, bilateral and multilateral. The standard is protecting the forging investors. If a state is enforcing a restriction with an effect equivalent to a ban on cross-border data flow, what is the relation of that restriction to the fair and equitable treatment standard?
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Pal, Terek. "Unapređenje kvaliteta alata za livenje pod pritiskom primenom tehnologija inženjerstva površina." Phd thesis, Univerzitet u Novom Sadu, Fakultet tehničkih nauka u Novom Sadu, 2016. http://www.cris.uns.ac.rs/record.jsf?recordId=101472&source=NDLTD&language=en.
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Proučavane su koroziona postojanost i tendencija lepljenja različitihmaterijala u kontaktu sa tečnom Al–Si–Cu legurom. Ispitivanjem suobuhvaćeni čelik za rad na toplo, plazma nitrirani čelik i dupleksslojevi sa CrN, TiAlN, TiAlSiN i CrAlN prevlakama, različitog nivoapovršinske hrapavosti. Za ispitivanja pomenutih fenomenaprimenjena je metoda izvlačenja, koja je unapređena kako bi se povećalenjena tačnost i verodostojnost simulacije procesa livenja. Korozioniefekti su pojačani tako što su uzorci osim kratkog kontakta sa odlivkomzadržavani i u dužim periodima u kontaktu sa tečnom legurom (5 i 20min). Uprkos opštim stavovima, za ispitivane materijale jeustanovljeno da su sile izvlačenja uzoraka iz Al–Si–Cu odlivakanezavisne od njihovog hemijskog sastava. Uticaj hrapavosti je izraženkod uzoraka sa prevlakama kod kojih pri smanjenju hrapavosti dolazi dopovećanja sile izvlačenja. Sve ispitane prevlake su sklone mehaničkomlepljenju Al–Si–Cu legure za svoje površine, ali sa aspekta korozije utečnom metalu značajno prevazilaze performanse čelika i plazmanitriranog sloja. Duži kontakt livene legure sa površinama prevlakauzrokovao je niže vrednosti sila izvlačenja, što je posledicaoksidacije površina prevlaka. Ustanovljeno je da su ispitivaneprevlake inertne ka tečnoj leguri aluminijuma. Međutim, dolazi dooksidacije i korozije materijala podloge kroz greške rasta koje suprisutne u prevlakama. Stečena znanja o identifikovanimmehanizmima habanja i propadanja zaštitnih slojeva prevlakaposlužiće daljem razvoju dupleks slojeva namenjenih za zaštitu alataza livenje pod pritiskom.<br>Corrosion resistance and soldering tendency of different materials in moltenAl–Si–Cu alloy were studied. Hot-working tool steel, plasma nitrided steel andduplex layers with CrN, TiAlN, TiAlSiN and CrAlN top coatings, which wereproduced to various degree of surface roughness, were covered by the study.An ejection test was employed for investigation of the concerned phenomena.The ejection test was improved in order to increase its accuracy and thereliability of process simulation. Samples were examined in both short andextended periods of contact (5 and 20 min) with liquid casting. Castingsolidification was extended in order to intensify the corrosion effects. Contraryto common findings, it was found that the ejection force of the investigatedmaterials does not depend on their chemical composition. For the coatedsamples, a pronounced dependence of the ejection force on the surfaceroughness was found. The ejection force increases with decrease in surfaceroughness. All investigated coatings are prone to mechanical soldering by Al–Si–Cu alloy. Still, their corrosion resistance substantially exceeds the corrosionresistance of steel and plasma nitrided layer. Longer exposure of coatedsamples to cast alloy induced lower ejection forces, which is a consequenceof coatings oxidation. It was found that the investigated coatings are inert toliquid aluminium. However, the underlying material undergoes oxidation andcorrosion through coating growth defects. The findings concerning the wearmechanisms of protective layers support further development of duplex layersintended for die casting tools protection.
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Achuo, George. "Partner satisfaction and renewal likelihood in consumer supported agriculture (CSA) : a case study of The Equiterre CSA network." Thesis, McGill University, 2003. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=19555.
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Johansson, Martin. "Hårdgörning av Asp." Thesis, Växjö University, School of Technology and Design, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:vxu:diva-2291.
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<p>Hårdgörning av trä syftar till att göra materialet hårdare. Detta går att åstadkomma genom komprimering, det komprimerade materialet tenderar dock att återgå mot sin ursprungsform då materialet utsätts för fukt om ingen låsning sker. Låsningen kan ske mekaniskt i en treskiktskonstruktion som motverkar träets fuktrörelser. Dessa skivor har dock visat sig vara instabila och tidigare försök har uppvisat deformationer i form av kupning. Denna undersökning syftar till att utreda förutsättningarna för att använda komprimerad asp samt att ta fram underlag för framtagning av en kommersiell produkt.</p><p>Praktiska tester har genomförts för att studera hårdhet, återfjädring och densitet hos det komprimerade virket. Vidare har treskiktsskivor tagits fram för att testa om det går att få en stabil konstruktion genom att variera tjockleken på spärrskiktet. Även skillnader i acklimatiseringstid och fuktkvotens inverkan för virkets återfjädring har studerats.</p><p>Resultaten visar på att aspens hårdhet efter komprimering blir i samma nivå som bok och ask, en låg fuktkkvot vid komprimering av materialet ger en låg återfjädring, komprimerat material har en längre acklimatiseringstid till jämviktsfuktkvot och materialet går att låsa tvärs fiberriktningen i en treskiktskonstruktion.</p><br><p>To make wood harder it can be densified. This can be achieved by compression, the compressed material tends to return to the original shape when it is exposed to moisture fluxations and if no form of fixation occurs. The fixation can be done mechanically in a three-layer panel construction which reduce movements in the timber. These panels have been found to be unstable and previous attempts have shown deformations in form of cupping. This study aims to evaluate the conditions for using compressed aspen wood, and to provide a basis for development of a commercial product.</p><p>Practical tests have been conducted to study hardness, springback and density of the compressed wood. In addition, three-layer panels have been developed to test whether it is possible to have a stable construction by varying the thickness of the buttom layer. Differences in acclimatisation time and the moisture contents effect on the springback has aslo been studied.</p><p>The results show that the hardness of aspen wood after compression is in equal levels with beech and ashes, a low moisture contet provides a low springback, compressed timber have a longer time for acclimatisation and it is possible to fixate the material in the direction across the grain in a three-layer panel construction.</p>
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Mallangi, Siva Sai Reddy. "Low-Power Policies Based on DVFS for the MUSEIC v2 System-on-Chip." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-229443.
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Multi functional health monitoring wearable devices are quite prominent these days. Usually these devices are battery-operated and consequently are limited by their battery life (from few hours to a few weeks depending on the application). Of late, it was realized that these devices, which are currently being operated at fixed voltage and frequency, are capable of operating at multiple voltages and frequencies. By switching these voltages and frequencies to lower values based upon power requirements, these devices can achieve tremendous benefits in the form of energy savings. Dynamic Voltage and Frequency Scaling (DVFS) techniques have proven to be handy in this situation for an efficient trade-off between energy and timely behavior. Within imec, wearable devices make use of the indigenously developed MUSEIC v2 (Multi Sensor Integrated circuit version 2.0). This system is optimized for efficient and accurate collection, processing, and transfer of data from multiple (health) sensors. MUSEIC v2 has limited means in controlling the voltage and frequency dynamically. In this thesis we explore how traditional DVFS techniques can be applied to the MUSEIC v2. Experiments were conducted to find out the optimum power modes to efficiently operate and also to scale up-down the supply voltage and frequency. Considering the overhead caused when switching voltage and frequency, transition analysis was also done. Real-time and non real-time benchmarks were implemented based on these techniques and their performance results were obtained and analyzed. In this process, several state of the art scheduling algorithms and scaling techniques were reviewed in identifying a suitable technique. Using our proposed scaling technique implementation, we have achieved 86.95% power reduction in average, in contrast to the conventional way of the MUSEIC v2 chip’s processor operating at a fixed voltage and frequency. Techniques that include light sleep and deep sleep mode were also studied and implemented, which tested the system’s capability in accommodating Dynamic Power Management (DPM) techniques that can achieve greater benefits. A novel approach for implementing the deep sleep mechanism was also proposed and found that it can obtain up to 71.54% power savings, when compared to a traditional way of executing deep sleep mode.<br>Nuförtiden så har multifunktionella bärbara hälsoenheter fått en betydande roll. Dessa enheter drivs vanligtvis av batterier och är därför begränsade av batteritiden (från ett par timmar till ett par veckor beroende på tillämpningen). På senaste tiden har det framkommit att dessa enheter som används vid en fast spänning och frekvens kan användas vid flera spänningar och frekvenser. Genom att byta till lägre spänning och frekvens på grund av effektbehov så kan enheterna få enorma fördelar när det kommer till energibesparing. Dynamisk skalning av spänning och frekvens-tekniker (såkallad Dynamic Voltage and Frequency Scaling, DVFS) har visat sig vara användbara i detta sammanhang för en effektiv avvägning mellan energi och beteende. Hos Imec så använder sig bärbara enheter av den internt utvecklade MUSEIC v2 (Multi Sensor Integrated circuit version 2.0). Systemet är optimerat för effektiv och korrekt insamling, bearbetning och överföring av data från flera (hälso) sensorer. MUSEIC v2 har begränsad möjlighet att styra spänningen och frekvensen dynamiskt. I detta examensarbete undersöker vi hur traditionella DVFS-tekniker kan appliceras på MUSEIC v2. Experiment utfördes för att ta reda på de optimala effektlägena och för att effektivt kunna styra och även skala upp matningsspänningen och frekvensen. Eftersom att ”overhead” skapades vid växling av spänning och frekvens gjordes också en övergångsanalys. Realtidsoch icke-realtidskalkyler genomfördes baserat på dessa tekniker och resultaten sammanställdes och analyserades. I denna process granskades flera toppmoderna schemaläggningsalgoritmer och skalningstekniker för att hitta en lämplig teknik. Genom att använda vår föreslagna skalningsteknikimplementering har vi uppnått 86,95% effektreduktion i jämförelse med det konventionella sättet att MUSEIC v2-chipets processor arbetar med en fast spänning och frekvens. Tekniker som inkluderar lätt sömn och djupt sömnläge studerades och implementerades, vilket testade systemets förmåga att tillgodose DPM-tekniker (Dynamic Power Management) som kan uppnå ännu större fördelar. En ny metod för att genomföra den djupa sömnmekanismen föreslogs också och enligt erhållna resultat så kan den ge upp till 71,54% lägre energiförbrukning jämfört med det traditionella sättet att implementera djupt sömnläge.
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Ku, Ching-te, and 古清德. "The Style,Effect,and Contextual Factors of Charismatic Leadership: A Case of the Founder of a Famous Internet Enterprise." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/23078721766200178637.
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碩士<br>元智大學<br>管理碩士在職專班<br>100<br>ABSTRACT
Leadership and Management are two sides of TMT’s routine jobs. Management comprises 5 fields, i.e. production, marketing, human resource, development &; research, and finance. There are various tools and research for managers, but leadership is another story. Research for leadership expanded over 2 or 3 decades, however, few tools and formulas in practices like fields of management do. That’s because there are a lot of art-like techniques involved. No way to follow an instruction to reach success like “1+1=2”.
The Charismatic leadership, one kind of leadership, is actually surrounded by a mythic halo. With a case from the founder of a well-known telecom company, the study analyses the behavior of the leader and pro &; con of the Charismatic leadership. We hope to investigate characteristics and further effects of this kind of leadership much more through the typical Charismatic leadership case.
The study interviewed 5 subjects that worked with the leader for a long time. As a semi-structured interview, it leads interviewees to talk about behavior style of leadership, and effect to a person or organization. Furthermore, interviewees were also asked to mention personality shift or transformation of the leader over these years, course to start up a company, and interactive model with members/partners. We hope the study draw a complete picture about personality of the leader from youth to maturity, not only an analysis of leadership behavior. Through the whole picture of the leader, then we can conclude some factors, cause and effects that lead to a Charismatic leadership.
The study concluded a result that almost matches the mainstream leadership theory. The Charismatic leadership carries out higher effectiveness and efficiency on leading and more employee satisfaction from the leader. And members pay more respect and trust to the leader. However, the study also issues some points of view that others’ researches did not mention before as follow.
1. The dark side of influence from the Charismatic leadership
2. Scale of organization follows major partners of the charismatic leader.
3. The succession planning issue.
All these issues above will be discussed in the case. Although with a single case, we use a cross-reference technique to compare each interview transcript and a qualitative research approach to analyze context of manuscripts. Finally we hope the study could come out with a valuable result for this kind of leadership. And the “real &; live” case can reflect some advantage and disadvantage of the Charismatic leadership as a manager’s reference.
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Nullmeier, Jens. "The Coalescent in Boundary-Limited Range Expansions." Doctoral thesis, 2014. http://hdl.handle.net/11858/00-1735-0000-0023-9903-5.
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Bhérer, Claude. "Ramifications génétiques et démographiques de l'effet fondateur québécois." Thèse, 2014. http://hdl.handle.net/1866/11846.
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Les événements fondateurs et les expansions territoriales peuvent promouvoir une cascade de changements génétiques et ont ainsi pu jouer un rôle important au cours de l’histoire évolutive de l’Homme moderne. Or, chez les populations humaines, les conséquences évolutives et la dynamique démographique des processus de colonisation demeurent largement méconnues et difficiles à étudier. Dans cette thèse, nous avons utilisé les généalogies de la population fondatrice canadienne-française ainsi que des données génomiques pour étudier ces questions. Les analyses génomiques et généalogiques, remarquablement concordantes, ont dévoilé un nouveau portrait détaillé de la structure de la population du Québec, incluant un continuum de diversité génétique dans l’axe ouest/est et des sous-populations significativement différenciées. L’analyse de l’immigration fondatrice a montré que virtuellement tous les Canadiens français sont métissés. Allant à l’encontre d’une prétendue homogénéité génétique de la population, nos résultats démontrent que le peuplement des régions a engendré une rapide différentiation génétique et expliquent certaines signatures régionales de l’effet fondateur. De plus, en suivant les changements évolutifs dans les généalogies, nous avons montré que les caractéristiques des peuplements fondateurs peuvent affecter les traits liés à la fécondité et au succès reproducteur. Cette thèse offre une meilleure compréhension du patrimoine génétique du Québec et apporte des éléments de réponse sur les conséquences évolutives des événements fondateurs.<br>Founding events and range expansions can promote a cascade of genetic changes and may have played an important role in the evolutionary history of modern humans. Yet the evolutionary consequences and demographic dynamics of these colonization processes remain poorly documented and challenging to study in human populations. In this thesis, we used deep-rooted genealogies from the French Canadian founder population in addition to genomic data to address these questions. Genomic and genealogical analyses were remarkably concordant and revealed a new portrait of Quebec fine-scale population structure, including a continuum of genetic diversity in the west/east axis and sub-populations significantly differentiated. The analysis of the founding immigration showed that virtually all French Canadians are admixed. Contrary to the idea of homogeneity of the population, our results demonstrate that the regional settlement histories led to a rapid genetic differentiation and explain some regional signatures of the founder effect. By monitoring evolutionary changes in real genealogies, we show that founding events impact fertility traits and reproductive success. This thesis leads to a better understanding of the genetic heritage of Quebec and provides insights on how peopling of new territories shaped human evolution.
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Bourassa, Cynthia. "Découverte d'un gène causant une ataxie spastique héréditaire dominante dans la population de Terre-Neuve." Thèse, 2012. http://hdl.handle.net/1866/7061.
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Les ataxies spastiques héréditaires forment une famille hétérogène de désordres qui ont des points communs avec les ataxies héréditaires et les paraplégies spastiques héréditaires. Un de ces éléments est une ataxie, soit une difficulté de coordination des membres souvent due à un dommage au cervelet. L’autre est une spasticité des membres inférieurs, souvent due à des dommages à la voie cortico-spinale. Une seule ataxie spastique à hérédité autosomique dominante a été rapportée dans la littérature, et il s’agit de SPAX1. À l’aide de trois familles de Terre-Neuve présentant ce phénotype, le locus a été identifié en 2002. Dans ce mémoire, c’est de la découverte du gène causal dont il est question. La mutation a été trouvée dans le gène VAMP1, qui encode la protéine synaptobrévine 1, une protéine synaptique impliquée dans l’exocytose des neurotransmetteurs. Il est aussi question de la caractérisation fonctionnelle de la mutation sur l’ARN et des conséquences possibles sur la protéine, concordant avec les symptômes de la maladie.<br>Hereditary spastic ataxias comprise a family of heterogeneous disorders resembling both hereditary ataxias and hereditary spastic paraplegias. The similar symptoms are ataxia, which is a problem with limb coordination due to cerebellar damage, and lower-limb spasticity due to corticospinal tract degeneration. Only one spastic ataxia inherited in an autosomal dominant fashion has been reported in the literature: SPAX1. The locus was identified in 2002 using three families from Newfoundland with the specific phenotype. This thesis reports the discovery of the causative mutation in the VAMP1 gene, which encodes VAMP1/synaptobrevin 1, a synaptic protein involved in neurotransmitter exocytosis. Experiments characterizing the effect of the mutation on RNA were conducted, leading to a possible molecular explanation of the symptoms.
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Putorti, Maria Lisa. "Caractérisation clinique et génétique d’une famille canadienne-française atteinte de la neuropathie héréditaire sensitive avec rétinite pigmentaire et ataxie." Thèse, 2010. http://hdl.handle.net/1866/4109.
Full textAbstract:
La complexité de l’étude des neuropathies héréditaires provient de leur hétérogénéité clinique et génétique et de la diversité des fibres composant les nerfs périphériques. Cette complexité se reflète dans les nombreuses classifications différentes. Les neuropathies héréditaires se classifient entre autres selon leur mode de transmission et leur atteinte sensitive, autonomique et motrice. Les neuropathies héréditaires sensitives et autonomiques (NHSA) se présentent avec une perte de la sensation distale aux membres, accompagnée d’autres manifestations selon le type de NHSA. L’étude des NHSA est facilitée lorsqu’il existe des grappes de familles originaires de régions du Québec où des effets fondateurs pour des maladies récessives ont déjà été identifiés. Nous avons recruté une grande famille canadienne-française originaire de Paspébiac dans la Baie-des-Chaleurs dans laquelle nous avons identifié quatre cas atteints d’une neuropathie héréditaire sensitive avec rétinite pigmentaire et ataxie (NHSRPA). Nous avons émis l’hypothèse que nous étions en présence d’une nouvelle forme de neuropathie héréditaire sensitive récessive à effet fondateur. Afin d’identifier la position chromosomique du gène muté responsable de la NHSRPA, nous avons tout d’abord complété un criblage du génome en génotypant des marqueurs microsatellites «single tandem repeat» (STR) sur des individus clés et nous avons ensuite procédé à une analyse de liaison génétique paramétrique. Ces études nous ont permis de lier cette famille au chromosome 1 et de définir un premier intervalle candidat de 6,7 Mb. Grâce à un génotypage de marqueurs «single nucleotide polymorphism» (SNP), nous avons réduit l’intervalle candidat à 5,3 Mb au locus 1q32,2-q32,3. Cette région contient 44 gènes candidats. Une revue plus fine de la littérature a fait ressortir qu’une famille espagnole et une américaine de souche hollandaise souffrant de la même maladie avaient déjà été liées au même locus. L’origine possiblement basque de notre famille gaspésienne nous a poussé à comparer l’haplotype porteur avec celui de la famille espagnole qui, quoi que gitane, provient du pays basque espagnol. Ces travaux ont démontré le partage d’une région de 203 kb. Afin de rétrécir davantage notre intervalle candidat, nous avons comparé les haplotypes des cas entre les deux familles et nous avons identifié un dernier intervalle candidat de 60 SNP au locus 1q32,3. Cette région ne contient que quatre gènes candidats dont le plus intéressant est le gène «activating transcription factor» (ATF3). À ce jour, aucune mutation n’a été trouvée dans le gène ATF3 et les gènes FAM71A, BATF3 et NSL1. Des expériences supplémentaires sont nécessaires afin d’identifier le gène muté responsable de la NHSRPA.<br>Hereditary neuropathies study’s complexity comes from their clinical and genetic heterogeneity and the peripheral nerves fibers’ diversity. This complexity leads to numerous different classifications. Hereditary neuropathies are classified based on the transmission mode and the sensitive, autonomic and motor affection. Hereditary sensory and autonomic neuropathies (HSAN) present themselves with members’ distal loss and other manifestations depending on the HSAN type. HSAN study can be facilitated when there are existing family grapes originating from Quebec regions where recessive diseases founder effects have been identified. We have recruited a large French-Canadian family originating from Paspébiac in the Baie-des-Chaleurs in which we have identified four cases affected by a hereditary sensory neuropathy with retinitis pigmentosa and ataxia (HSNRPA). We have hypothesized that we were in presence of a new form of recessive hereditary sensitive neuropathy with founder effect. In order to identify the HSNRPA causing mutated gene chromosomal position, we first completed a genome wide scan by genotyping microsatellite single tandem repeat (STR) markers on informative individuals and we have then proceeded to a parametric genetic linkage analysis. These studies allowed us to link this family to chromosome 1 and define a first candidate interval of 6.7 Mb. Second to the single nucleotide polymorphism (SNP) markers genotyping, we have reduced the candidate interval at 5.3 Mb on locus 1q32.2-q32.3. This region contains 44 genes. A finer literature review made us realize that a Spanish family and an American from Dutch origin suffering from the same disease had already been linked to the same locus. The possible Gaspesian family’s Basque origins brought us to compare their carrier haplotype with the Spanish family’s, although Gypsy but coming from the Spanish Basque country. This work has demonstrated a shared region of 203 kb. In order to further refine our candidate interval, we have compared the haplotypes of the cases between the two families and we have identified a last candidate interval of 60 SNP at locus 1q32.3. This region contains only four candidate genes, the activating transcription factor (ATF3) gene being the most interesting one. Until today, no mutation has been found in the ATF3 gene and in the FAM71A, BATF3 and NSL1 genes. Further experiments will be necessary in order to identify the HSNRPA causing mutated gene.