Dissertations / Theses on the topic 'Mutation'

To see the other types of publications on this topic, follow the link: Mutation.

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the top 50 dissertations / theses for your research on the topic 'Mutation.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.

1

Komp, Lindgren Patricia. "Mutations and Mutation Rate in the Development of Fluoroquinolone Resistance." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-8275.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Ibrahim, Daniel Murad. "ChIP-seq reveals mutation-specific pathomechanisms of HOXD13 missense mutations." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2015. http://dx.doi.org/10.18452/17102.

Full text
Abstract:
Mutationen von Transkriptionsfaktoren (TF) betreffen nicht nur die Funktion des TFs, sondern auch die Expression seiner Zielgene und liegen häufig angeborenen Entwicklungsdefekten zugrunde. Über 20 Mutationen in HOXD13, einem TF der die Entwicklung der Extremitäten kontrolliert, sind bisher als Ursache verschiedenartiger Extremitätenfehlbildungen entdeckt worden. Eine molekularbiologische Grundlage für die Vielgestaltigkeit der HOXD13-Mutationen ist jedoch unbekannt. Die bisherigen Methoden zur funktionellen Charakterisierung von TF-Mutationen ermöglichten eine lediglich eingeschränkte Interpretation der molekularen Pathomechanismen. Die kürzlich entwickelte ChIP-seq Methode ermöglicht eine umfassende, funktionelle Charakterisierung eines TFs. In dieser Arbeit wurde eine Methode etabliert, um eine Vielzahl von Transkriptionsfaktoren und TF-Mutationen systematisch zu untersuchen. Zur Validierung wurden zwei neue Punktmutationen in HOXD13, p.Q317K und p.R298Q, charakterisiert. Beide Mutationen betreffen die DNA-bindende Domäne von HOXD13, rufen aber stark unterschiedliche Fehlbildungen hervor. Die Ergebnisse zeigen, dass die HOXD13Q317K Mutante eine veränderte Sequenzspezifität aufweist, welche nun jener eines anderen TFs, PITX1, ähnelt. Auch genomweit zeigt HOXD13Q317K ein Bindungsprofil, welches eher PITX1 als HOXD13wt entspricht. Durch weitere, unabhängige Analysen und Experimente wurde bestätigt, dass die p.Q317K Mutation HOXD13 in einen TF mit PITX1-ähnlichen Eigenschaften verändert. Die HOXD13R298Q-Mutante zeigt eine weitgehend unveränderte Bindungssequenz gegenüber HOXD13wt, jedoch eine veränderte Zusammensetzung der genomischen Bindestellen. Dies weist, in Kombination mit dem humanen Phänotyp auf einen dominant-negativen Pathomechanismus dieser Mutanten hin. Zusammengenommen zeigt diese Arbeit durch die Erhebung von experimentellen Daten, dass klar unterscheidbare molekularbiologische Mechanismen den HOXD13Q317K- und HOXD13R298Q-Mutationen zugrunde liegen.
Mutations in transcription factors (TF) do not only affect the function of the TF, but also the expression of its target genes and are frequently underlying congenital malformations. More than 20 distinct pathogenic mutations in HOXD13, a TF controlling limb development, have been associated with a broad range of limb malformations. However, a molecular basis underlying the variability of HOXD13-associated phenotypes remains elusive. To date, the experimental methods used to functionally characters TF mutations have allowed only limited insights into the underlying molecular pathomechanisms. The recently developed ChIP-seq technology has proven to be a powerful method to profile the binding characteristics of TFs; however a number of technical hurdles hinder its application for functional characterization of mutant TFs. This work describes the establishment of a ChIP-seq approach to investigate a wide spectrum of TFs and TF mutations. The approach was applied to characterize two previously unknown missense mutations in HOXD13, p.Q317K and p.R298Q, which both alter the DNA-binding domain of HOXD13 but cause very different disease phenotypes. The results show that the HOXD13Q317K mutant has an altered sequence specificity that resembles the recognition sequence of another TF, PITX1. Further, the genome-wide binding pattern of HOXD13Q317K shifts towards a more PITX1-like binding pattern. Even further analysis and viral overexpression in chicken limb buds confirm that the mutation partially converts HOXD13Q317K into a TF with PITX1-like properties. The HOXD13R298Q has a largely unchanged sequence specificity, but an altered composition of genomic binding sites. This, in combination with the human phenotype, indicates that the mutant might act in a dominant-negative manner. Collectively, this work shows through generation of direct experimental evidence, that clearly distinct molecular mechanisms underlie the pathogenicity of HOXD13Q317K and HOXD13R298Q mutations.
APA, Harvard, Vancouver, ISO, and other styles
3

Hagman, Hans. "Mutation Testing : A comparison of mutation selection methods." Thesis, Högskolan i Skövde, Institutionen för kommunikation och information, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-6569.

Full text
Abstract:
Software is all around us in our lives in the industrialized world, and we as a society and individuals need it to function correctly. Software testing fills the role of performing behavior audits, to guide the correction of the software to its intended behavior. The consequences of faulty software can range to the late arrival of trains, to nuclear meltdowns. This places quality requirements on the software of various levels. Program based mutation testing provides a high level of faultfinding capability. It does this by injecting many synthetic faults into the code under test, as described by mutation operators. These faults are used to search for testcases that would identify such faults, and consequently find real faults that the synthetic faults mimic. However, mutation testing is costly on three accounts; each mutant of the original code is compiled, each mutant should ideally have an associated testcase to reveal that fault the mutant contains, finally the testcases are analyzed thoroughly by looking the output of the original and mutants to reveal the error in behavior. In order to reduce cost while maintaining a high level of faultfinding, selective mutation testing is investigated, it uses a subset of all the available mutation operators. The investigation found that using Absolute value-, and Relational operator-, mutation reduces cost of mutation testing by 80%, while uncovering 83% of the injected faults.
APA, Harvard, Vancouver, ISO, and other styles
4

Krasovec, Marc. "Estimation des taux de mutation : implications pour la diversification et l'évolution du phytoplancton eucaryote." Thesis, Paris 6, 2016. http://www.theses.fr/2016PA066371/document.

Full text
Abstract:
Les mutations sont la principale source de diversité sur laquelle agit la sélection pour permettre aux espèces de s'adapter. Les études de l'effet des mutations sur la survie et du taux de mutation sont donc essentielles pour mieux comprendre l'évolution. Par une approche d'expérience d'accumulation de mutations, nous étudions ces deux questions chez cinq modèles d'algues vertes (Ostreococcus tauri, O. mediterraneus, Bathycoccus prasinos, Micromonas pusilla, et Picochlorum RCC4223). Il est mis en évidence une diminution de la fitness au cours du temps en raison des mutations délétères, et une importante interaction génotype-environnement sur l'effet des mutations. Le taux de mutation varie aux échelles intra-génomique et inter-spécifique, avec deux principaux résultats: une augmentation du taux de mutation dans les régions non codantes et une augmentation du taux de mutation avec la taille du génome chez les eucaryotes et en fonction de l'écart à l'équilibre en GC du génome. Aussi, l'assemblage et l'annotation d'une picoalgue du genre Picochlorum permettent d'étudier le rôle des transferts horizontaux de gènes chez les Chlorophytes
Mutations are the main source of diversity on which selection acts to allow species to adapt. Studies of the effect of mutations on survival and estimation of spontaneous mutation rates are essential to better understand evolution. Using mutation accumulation experimental approach, we investigated the issues of mutation effects and mutation rate in five models of green algae (Ostreococcus tauri, O. mediterraneus, Bathycoccus Prasinos, Micromonas pusilla, and Picochlorum RCC4223). It highlighted a decline in fitness over time because of deleterious mutations, and a significant genotype-environment interaction on the fitness effect of mutations. The mutation rate varies at inter-specific and intra-genomic scales, with two main results: a raise of the mutation rate in non-coding regions in accordance with trancriptional-coupled repair, and an increase of the mutation rate with an increase of the genome size in eukaryotes and the GC content deviation from the equilibrium. Also, a new Picochlorum genome is provided to investigate the role of horizontal gene transfer in the Chlorophyta group
APA, Harvard, Vancouver, ISO, and other styles
5

Krasovec, Marc. "Estimation des taux de mutation : implications pour la diversification et l'évolution du phytoplancton eucaryote." Electronic Thesis or Diss., Paris 6, 2016. https://accesdistant.sorbonne-universite.fr/login?url=https://theses-intra.sorbonne-universite.fr/2016PA066371.pdf.

Full text
Abstract:
Les mutations sont la principale source de diversité sur laquelle agit la sélection pour permettre aux espèces de s'adapter. Les études de l'effet des mutations sur la survie et du taux de mutation sont donc essentielles pour mieux comprendre l'évolution. Par une approche d'expérience d'accumulation de mutations, nous étudions ces deux questions chez cinq modèles d'algues vertes (Ostreococcus tauri, O. mediterraneus, Bathycoccus prasinos, Micromonas pusilla, et Picochlorum RCC4223). Il est mis en évidence une diminution de la fitness au cours du temps en raison des mutations délétères, et une importante interaction génotype-environnement sur l'effet des mutations. Le taux de mutation varie aux échelles intra-génomique et inter-spécifique, avec deux principaux résultats: une augmentation du taux de mutation dans les régions non codantes et une augmentation du taux de mutation avec la taille du génome chez les eucaryotes et en fonction de l'écart à l'équilibre en GC du génome. Aussi, l'assemblage et l'annotation d'une picoalgue du genre Picochlorum permettent d'étudier le rôle des transferts horizontaux de gènes chez les Chlorophytes
Mutations are the main source of diversity on which selection acts to allow species to adapt. Studies of the effect of mutations on survival and estimation of spontaneous mutation rates are essential to better understand evolution. Using mutation accumulation experimental approach, we investigated the issues of mutation effects and mutation rate in five models of green algae (Ostreococcus tauri, O. mediterraneus, Bathycoccus Prasinos, Micromonas pusilla, and Picochlorum RCC4223). It highlighted a decline in fitness over time because of deleterious mutations, and a significant genotype-environment interaction on the fitness effect of mutations. The mutation rate varies at inter-specific and intra-genomic scales, with two main results: a raise of the mutation rate in non-coding regions in accordance with trancriptional-coupled repair, and an increase of the mutation rate with an increase of the genome size in eukaryotes and the GC content deviation from the equilibrium. Also, a new Picochlorum genome is provided to investigate the role of horizontal gene transfer in the Chlorophyta group
APA, Harvard, Vancouver, ISO, and other styles
6

Lee, Angela Waishan. "Hair-loss mutation (dep) caused by a mutation in palmitoyl transferase Zdhhc21." Thesis, University of Edinburgh, 2008. http://hdl.handle.net/1842/29217.

Full text
Abstract:
The recessive hair loss mutant, dep, contains a mutation (del-233F) at the C-terminal of Zdhhc21. Wild-type Zdhhc21 has been shown to enhance palmitoylation of several specific substrates in a transfected cell assay. Zdhhc21 localises to the cis-Golgi, whereas the mutant protein is mislocalised and is inactive in palmitoylation. We verified the candidacy of Zdhhc21 by transgenic BAC rescue. Dep is characterised by progressive hair loss, hyperplasia of the sebaceous glands, the interfollicular epidermis and the outer root sheath. In-situ hybridisation and immunohistochemistry show that both wild-type and dep mRNA and protein are present in the inner root sheath (IRS). Phenotypic characterisation using molecular markers in cell culture and on skin sections reveals abnormalities that suggest a lack of correct hair shaft differentiation in dep. We speculate that dep may have a direct or indirect effect on 4 members of the Wnt family – essential regulators of hair shaft differentiation – because of their co-expression in the IRS and because the dep mutant exhibits a Wnt-deficient phenotype. This hypothesis may provide an example of how local signalling centres may be established to allow for spatiotemporal gene expression. Furthermore, dep is the first mouse model that provides direct evidence of an enzymatic activity of the Dhhc family.
APA, Harvard, Vancouver, ISO, and other styles
7

Drechsel, Dieter. "Evolution and Mutation Physics." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2011. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-69962.

Full text
Abstract:
Base rivalry arises at replication of monotonous DNA – sequences. Irreparable mutations can arise by tunnel processes if the developed energy is high enough. The tunnel probability depends not only on the base rivalry energy but also depends on the temperature of surroundings. The tunnel probability diminishes with decreasing temperature. The cytoplasm viscosity increases in the long term with decreasing temperature. The length of the monotonous sequence in which happens an irreparable mutation (caused by base rivalry) then will be larger than at higher temperatures. This means that the possible distribution variety of all base components on the given matrix will diminish; therefore the probability increases that one base component which possesses the necessary energy, comes into the certain monotonous sequence to provoke a tunnel process. These different temperature dependences are the subject of the following examinations; they lead to the equation (32) which is valid for coming off of an irreparable mutation which is caused by base rivalry. Because of the dependence between temperature change and mutating sequence length from s1 to s1+1 (expressed in this equation), there result informations about evolution, and informations about mutation of DNA – viruses. The calculations are performed with very small DNA fragments so called residual fragments.
APA, Harvard, Vancouver, ISO, and other styles
8

Duncan, Ishbel M. M. "Strong mutation testing strategies." Thesis, Durham University, 1993. http://etheses.dur.ac.uk/5771/.

Full text
Abstract:
Mutation Testing (or Mutation Analysis) is a source code testing technique which analyses code by altering code components. The output from the altered code is compared with output from the original code. If they are identical then Mutation Testing has been successful in discerning a weakness in either the test code or the test data. A mutation test therefore helps the tester to develop a program devoid of simple faults with a well developed test data set. The confidence in both program and data set is then increased. Mutation Analysis is resource intensive. It requires program copies, with one altered component, to be created and executed. Consequently, it has been used mainly by academics analysing small programs. This thesis describes an experiment to apply Mutation Analysis to larger, multi-function test programs. Mutations, alterations to the code, are induced using a sequence derived from the code control flow graph. The detection rate of live mutants, programs whose output match the original, was plotted and compared against data generated from the standard technique of mutating in statement order. This experiment was repeated for different code components such as relational operators, conditional statement or pointer references. A test was considered efficient if the majority of live mutants was detected early in the test sequence. The investigations demonstrated that control flow driven mutation could improve the efficiency of a test. However, the experiments also indicated that concentrations of live mutants of a few functions or statements could effect the efficiency of a test. This conclusion lead to the proposal that mutation testing should be directed towards functions or statements containing groupings of the code component that give rise to the live mutants. This effectively forms a test focused onto particular functions or statements.
APA, Harvard, Vancouver, ISO, and other styles
9

Williamson, David. "Haemoglobin mutation and instability." Thesis, Open University, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.315297.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

Jia, Y. "Higher order mutation testing." Thesis, University College London (University of London), 2013. http://discovery.ucl.ac.uk/1401264/.

Full text
Abstract:
Mutation testing is a fault-based software testing technique that has been studied widely for over three decades. To date, work in this field has focused largely on first order mutants because it is believed that higher order mutation testing is too computationally expensive to be practical. This thesis argues that some higher order mutants are potentially better able to simulate real world faults and to reveal insights into programming bugs than the restricted class of first order mutants. This thesis proposes a higher order mutation testing paradigm which combines valuable higher order mutants and non-trivial first order mutants together for mutation testing. To overcome the exponential increase in the number of higher order mutants a search process that seeks fit mutants (both first and higher order) from the space of all possible mutants is proposed. A fault-based higher order mutant classification scheme is introduced. Based on different types of fault interactions, this approach classifies higher order mutants into four categories: expected, worsening, fault masking and fault shifting. A search-based approach is then proposed for locating subsuming and strongly subsuming higher order mutants. These mutants are a subset of fault mask and fault shift classes of higher order mutants that are more difficult to kill than their constituent first order mutants. Finally, a hybrid test data generation approach is introduced, which combines the dynamic symbolic execution and search based software testing approaches to generate strongly adequate test data to kill first and higher order mutants.
APA, Harvard, Vancouver, ISO, and other styles
11

Maxwell, Megan Amanda, and n/a. "PEX1 Mutations in Australasian Patients with Disorders of Peroxisome Biogenesis." Griffith University. School of Biomolecular and Biomedical Science, 2004. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20040219.100649.

Full text
Abstract:
The peroxisome is a subcellular organelle that carries out a diverse range of metabolic functions, including the b-oxidation of very long chain fatty acids, the breakdown of peroxide and the a-oxidation of fatty acids. Disruption of peroxisome metabolic functions leads to severe disease in humans. These diseases can be broadly grouped into two categories: those in which a single enzyme is defective, and those known as the peroxisome biogenesis disorders (PBDs), which result from a generalised failure to import peroxisomal matrix proteins (and consequently result in disruption of multiple metabolic pathways). The PBDs result from mutations in PEX genes, which encode protein products called peroxins, required for the normal biogenesis of the peroxisome. PEX1 encodes an AAA ATPase that is essential for peroxisome biogenesis, and mutations in PEX1 are the most common cause of PBDs worldwide. This study focused on the identification of mutations in PEX1 in an Australasian cohort of PBD patients, and the impact of these mutations on PEX1 function. As a result of the studies presented in this thesis, twelve mutations in PEX1 were identified in the Australasian cohort of patients. The identified mutations can be broadly grouped into three categories: missense mutations, mutations directly introducing a premature termination codon (PTC) and mutations that interrupt the reading frame of PEX1. The missense mutations that were identified were R798G, G843D, I989T and R998Q; all of these mutations affect amino acid residues located in the AAA domains of the PEX1 protein. Two mutations that directly introduce PTCs into the PEX1 transcript (R790X and R998X), and four frameshift mutations (A302fs, I370fs, I700fs and S797fs) were identified. There was also one mutation found in an intronic region (IVS22-19A>G) that is presumed to affect splicing of the PEX1 mRNA. Three of these mutations, G843D, I700fs and G973fs, were found at high frequency in this patient cohort. At the commencement of these studies, it was hypothesised that missense mutations would result in attenuation of PEX1 function, but mutations that introduced PTCs, either directly or indirectly, would have a deleterious effect on PEX1 function. Mutations introducing PTCs are thought to cause mRNA to be degraded by the nonsense-mediated decay of mRNA (NMD) pathway, and thus result in a decrease in PEX1 protein levels. The studies on the cellular impact of the identified PEX1 mutations were consistent with these hypotheses. Missense mutations were found to reduce peroxisomal protein import and PEX1 protein levels, but a residual level of function remained. PTC-generating mutations were found to have a major impact on PEX1 function, with PEX1 mRNA and protein levels being drastically reduced, and peroxisomal protein import capability abolished. Patients with two missense mutations showed the least impact on PEX1 function, patients with two PTC-generating mutations had a severe defect in PEX1 function, and patients carrying a combination of a missense mutation and a PTC-generating mutation showed levels of PEX1 function that were intermediate between these extremes. Thus, a correlation between PEX1 genotype and phenotype was defined for the Australasian cohort of patients investigated in these studies. For a number of patients, mutations in the coding sequence of one PEX1 allele could not be identified. Analysis of the 5' UTR of this gene was therefore pursued for potential novel mutations. The initial analyses demonstrated that the 5' end of PEX1 extended further than previously reported. Two co-segregating polymorphisms were also identified, termed –137 T>C and –53C>G. The -137T>C polymorphism resided in an upstream, in-frame ATG (termed ATG1), and the possibility that the additional sequence represented PEX1 coding sequence was examined. While both ATGs were found to be functional by virtue of in vitro and in vivo expression investigations, Western blot analysis of the PEX1 protein in patient and control cell extracts indicated that physiological translation of PEX1 was from the second ATG only. Using a luciferase reporter approach, the additional sequence was found to exhibit promoter activity. When examined alone the -137T>C polymorphism exerted a detrimental effect on PEX1 promoter activity, reducing activity to half that of wild-type levels, and the -53C>G polymorphism increased PEX1 promoter activity by 25%. When co-expressed (mimicking the physiological condition) these polymorphisms compensated for each other to bring PEX1 promoter activity to near wild-type levels. The PEX1 mutations identified in this study have been utilised by collaborators at the National Referral Laboratory for Lysosomal, Peroxisomal and Related Genetic Disorders (based at the Women's and Children's Hospital, Adelaide), in prenatal diagnosis of the PBDs. In addition, the identification of three common mutations in Australasian PBD patients has led to the implementation of screening for these mutations in newly referred patients, often enabling a precise diagnosis of a PBD to be made. Finally, the strong correlation between genotype and phenotype for the patient cohort investigated as part of these studies has generated a basis for the assessment of newly identified mutations in PEX1.
APA, Harvard, Vancouver, ISO, and other styles
12

Maxwell, Megan Amanda. "PEX1 Mutations in Australasian Patients with Disorders of Peroxisome Biogenesis." Thesis, Griffith University, 2004. http://hdl.handle.net/10072/366184.

Full text
Abstract:
The peroxisome is a subcellular organelle that carries out a diverse range of metabolic functions, including the b-oxidation of very long chain fatty acids, the breakdown of peroxide and the a-oxidation of fatty acids. Disruption of peroxisome metabolic functions leads to severe disease in humans. These diseases can be broadly grouped into two categories: those in which a single enzyme is defective, and those known as the peroxisome biogenesis disorders (PBDs), which result from a generalised failure to import peroxisomal matrix proteins (and consequently result in disruption of multiple metabolic pathways). The PBDs result from mutations in PEX genes, which encode protein products called peroxins, required for the normal biogenesis of the peroxisome. PEX1 encodes an AAA ATPase that is essential for peroxisome biogenesis, and mutations in PEX1 are the most common cause of PBDs worldwide. This study focused on the identification of mutations in PEX1 in an Australasian cohort of PBD patients, and the impact of these mutations on PEX1 function. As a result of the studies presented in this thesis, twelve mutations in PEX1 were identified in the Australasian cohort of patients. The identified mutations can be broadly grouped into three categories: missense mutations, mutations directly introducing a premature termination codon (PTC) and mutations that interrupt the reading frame of PEX1. The missense mutations that were identified were R798G, G843D, I989T and R998Q; all of these mutations affect amino acid residues located in the AAA domains of the PEX1 protein. Two mutations that directly introduce PTCs into the PEX1 transcript (R790X and R998X), and four frameshift mutations (A302fs, I370fs, I700fs and S797fs) were identified. There was also one mutation found in an intronic region (IVS22-19A>G) that is presumed to affect splicing of the PEX1 mRNA. Three of these mutations, G843D, I700fs and G973fs, were found at high frequency in this patient cohort. At the commencement of these studies, it was hypothesised that missense mutations would result in attenuation of PEX1 function, but mutations that introduced PTCs, either directly or indirectly, would have a deleterious effect on PEX1 function. Mutations introducing PTCs are thought to cause mRNA to be degraded by the nonsense-mediated decay of mRNA (NMD) pathway, and thus result in a decrease in PEX1 protein levels. The studies on the cellular impact of the identified PEX1 mutations were consistent with these hypotheses. Missense mutations were found to reduce peroxisomal protein import and PEX1 protein levels, but a residual level of function remained. PTC-generating mutations were found to have a major impact on PEX1 function, with PEX1 mRNA and protein levels being drastically reduced, and peroxisomal protein import capability abolished. Patients with two missense mutations showed the least impact on PEX1 function, patients with two PTC-generating mutations had a severe defect in PEX1 function, and patients carrying a combination of a missense mutation and a PTC-generating mutation showed levels of PEX1 function that were intermediate between these extremes. Thus, a correlation between PEX1 genotype and phenotype was defined for the Australasian cohort of patients investigated in these studies. For a number of patients, mutations in the coding sequence of one PEX1 allele could not be identified. Analysis of the 5' UTR of this gene was therefore pursued for potential novel mutations. The initial analyses demonstrated that the 5' end of PEX1 extended further than previously reported. Two co-segregating polymorphisms were also identified, termed –137 T>C and –53C>G. The -137T>C polymorphism resided in an upstream, in-frame ATG (termed ATG1), and the possibility that the additional sequence represented PEX1 coding sequence was examined. While both ATGs were found to be functional by virtue of in vitro and in vivo expression investigations, Western blot analysis of the PEX1 protein in patient and control cell extracts indicated that physiological translation of PEX1 was from the second ATG only. Using a luciferase reporter approach, the additional sequence was found to exhibit promoter activity. When examined alone the -137T>C polymorphism exerted a detrimental effect on PEX1 promoter activity, reducing activity to half that of wild-type levels, and the -53C>G polymorphism increased PEX1 promoter activity by 25%. When co-expressed (mimicking the physiological condition) these polymorphisms compensated for each other to bring PEX1 promoter activity to near wild-type levels. The PEX1 mutations identified in this study have been utilised by collaborators at the National Referral Laboratory for Lysosomal, Peroxisomal and Related Genetic Disorders (based at the Women's and Children's Hospital, Adelaide), in prenatal diagnosis of the PBDs. In addition, the identification of three common mutations in Australasian PBD patients has led to the implementation of screening for these mutations in newly referred patients, often enabling a precise diagnosis of a PBD to be made. Finally, the strong correlation between genotype and phenotype for the patient cohort investigated as part of these studies has generated a basis for the assessment of newly identified mutations in PEX1.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Biomolecular and Biomedical Sciences
Full Text
APA, Harvard, Vancouver, ISO, and other styles
13

Curry, John Duncan. "Mutation monitoring in human populations." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ40453.pdf.

Full text
APA, Harvard, Vancouver, ISO, and other styles
14

Meischl, Christof. "NADPH oxidases and mutation analysis." [S.l. : Amsterdam : s.n.] ; Universiteit van Amsterdam [Host], 2003. http://dare.uva.nl/document/69587.

Full text
APA, Harvard, Vancouver, ISO, and other styles
15

Jones, Emma. "Characterisation of the robotic mutation." Thesis, University of Oxford, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.400190.

Full text
APA, Harvard, Vancouver, ISO, and other styles
16

Warkentin, Matthias. "Exchange Graphs via Quiver Mutation." Doctoral thesis, Universitätsbibliothek Chemnitz, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-153172.

Full text
Abstract:
Inspired by Happel's question, whether the exchange graph and the simplicial complex of tilting modules over a quiver algebra are independent from the multiplicities of multiple arrows in the quiver, we study quantitative aspects of Fomin and Zelevinsky's quiver mutation rule. Our results turn out to be very useful in the mutation-infinite case for understanding combinatorial structures as the cluster exchange graph or the simplicial complex of tilting modules, which are governed by quiver mutation. Using a class of quivers we call forks we can show that any such quiver yields a tree in the exchange graph. This allows us to provide a good global description of the exchange graphs of arbitrary mutation-infinite quivers. In particular we show that the exchange graph of an acyclic quiver is a tree if (and in fact only if) any two vertices are connected by at least two arrows. Furthermore we give classification results for the simplicial complexes and thereby obtain a partial positive answer to Happel's question. Another consequence of our findings is a confirmation of Unger's conjecture about the infinite number of components of the tilting exchange graph in all but finitely many cases. Finally we generalise and conceptualise our results by introducing what we call "polynomial quivers", stating several conjectures about "polynomial quiver mutation", and giving proofs in special cases.
APA, Harvard, Vancouver, ISO, and other styles
17

Henderson, Shirley. "The achondroplasia mutation rate paradox." Thesis, Open University, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.394800.

Full text
APA, Harvard, Vancouver, ISO, and other styles
18

Bunyan, David J. "Mutation screening in human diseases." Thesis, University of Southampton, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.241905.

Full text
APA, Harvard, Vancouver, ISO, and other styles
19

Huang, Zhan. "Mutation for multi-agent systems." Thesis, University of York, 2016. http://etheses.whiterose.ac.uk/19270/.

Full text
Abstract:
Although much progress has been made in engineering multi-agent systems (MAS), many issues remain to be resolved. One issue is that there is a lack of techniques that can adequately evaluate the effectiveness (fault detection ability) of tests or testing techniques for MAS. Another is that there are no systematic approaches to evaluating the impact of possible semantic changes (changes in the interpretation of agent programs) on agents' behaviour and performance. This thesis introduces syntactic and semantic mutation to address these two issues. Syntactic mutation is a technique that systematically generates variants ("syntactic mutants") of a description (usually a program) following a set of rules ("syntactic mutation operators"). Each mutant is expected to simulate a real description fault, therefore, the effectiveness of a test set can be evaluated by checking whether it can detect each simulated fault, in other words, distinguish the original description from each mutant. Although syntactic mutation is widely considered very effective, only limited work has been done to introduce it into MAS. This thesis extends syntactic mutation for MAS by proposing a set of syntactic mutation operators for the Jason agent language and showing that they can be used to generate real faults in Jason agent programs. By contrast, semantic mutation systematically generates variant interpretations ("semantic mutants") of a description following a set of rules ("semantic mutation operators"). Semantic mutation has two uses: to evaluate the effectiveness of a test set by simulating faults caused by misunderstandings of how the description is interpreted, and to evaluate the impact of possible semantic changes on agents' behaviour and performance. This thesis, for the first time, proposes semantic mutation for MAS, more specifically, for three logic based agent languages, namely Jason, GOAL and 2APL. It proposes semantic mutation operators for these languages, shows that the operators for Jason can represent real misunderstandings and are practically useful.
APA, Harvard, Vancouver, ISO, and other styles
20

Mathias, Shelley Frances. "Mutation selection using DNA technology." Thesis, University of Sussex, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.260060.

Full text
APA, Harvard, Vancouver, ISO, and other styles
21

Schafer, Robin. "A Structural Analysis of Mutation." Department of Linguistics, University of Arizona (Tucson, AZ), 1988. http://hdl.handle.net/10150/227234.

Full text
APA, Harvard, Vancouver, ISO, and other styles
22

Bennett, Lea-Christine. "Mutation screening and characterisation of mutational effects at transcript and protein level in cystic fibrosis /." [Bern] : [s.n.], 1999. http://www.ub.unibe.ch/content/bibliotheken_sammlungen/sondersammlungen/dissen_bestellformular/index_ger.html.

Full text
APA, Harvard, Vancouver, ISO, and other styles
23

Brandström, Mikael. "Bioinformatic analysis of mutation and selection in the vertebrate non-coding genome /." Uppsala : Acta Universitatis Upsaliensis Acta Universitatis Upsaliensis, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-8240.

Full text
APA, Harvard, Vancouver, ISO, and other styles
24

Smith, Matthew Liam Walker. "Mutation profiling in acute myeloid leukaemia." Thesis, Queen Mary, University of London, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.416112.

Full text
APA, Harvard, Vancouver, ISO, and other styles
25

Torkelson, Joel David. "Genome-wide hypermutation underlies adaptive mutation." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/mq22682.pdf.

Full text
APA, Harvard, Vancouver, ISO, and other styles
26

Elhaji, Youssef A. "Androgen receptor mutation in breast cancer." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0002/MQ44162.pdf.

Full text
APA, Harvard, Vancouver, ISO, and other styles
27

Makriyianni, Ioli. "Mutation analysis of hereditary breast cancers." Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=98760.

Full text
Abstract:
Mitochondrial background. Recent studies on cancer have detected many mutations and much variability in the mitochondrial genome, particularly in the non-coding region (D-loop). The present study set out to sequence and examine the hypervariable region I (HVR-I) of the D-loop and transfer RNA Leucine (tRNA Leu) for mutations in breast cancer patients. Methods. Tumor and normal tissues from 17 patients that carry mutations in either BRCA1 (n = 11), BRCA2 (n = 3) or are non-carriers of mutations in either gene (n = 3) were examined by direct genomic sequencing of PCR products. Results. We found 44 variants in the HVR-I of 16 patients, twenty-six were polymorphisms, four somatic variants, and fourteen variations were undetermined because corresponding (unaffected) normal tissue was not available. One BRCA1 mutated tumor had four somatic tumor variants (1/14). All other BRCA1/BRCA2 mutated tumors had no somatic variants. Nine out of 14 (64%) of these patients had a total 22 germline variants. One out of three (33%) non-carriers had four germ-line variants. No variants were found in tRNA Leu. A five kilobase deletion was also found as a germ-line variant in two of seven (29%) patients. There were no obvious differences in the frequency of homoplasmic variants in the mitochondrial genome between the BRCA1/BRCA2 mutation carriers and non-carriers. Conclusion. Direct genomic sequencing of PCR products showed that there were no striking differences in homoplasmic variants between tumor and normal tissue, thus homoplasmic variants in mtDNA did not have a role in tumorigenesis in our samples. We speculate that the marked differences in mutation frequencies observed amongst various studies could be the result of differences in the techniques used to generate and analyze the data.
EGFR background. Recent studies have identified mutations in the tyrosine kinase (TK) domain of the epidermal growth factor receptor (EGFR) in lung carcinomas. These mutations make the tumors sensitive to a molecular targeted drug called getifinib. Methods. We also sequenced the TK domain of EGFR in 16 breast cancer patients (BRCA1 = 9, BRCA2 = 4, non-carriers = 3) for mutations. Results. We did not find mutations reported previously in lung carcinomas but we identified other variants, in exons 18, 20 and 21 of the mutation carvers. We found one out of thirteen (eight percent) of the BRCA1/BRCA2 mutation carriers had somatic tumor variants, three out of thirteen (23%) patients had somatic variants found only in the adjacent normal tissue, and four out of thirteen (31%) patients had germ-line variants. The non-carriers did not have any variants. The variants found in the exons were two missense variants in exon 18 of two patients, three 'silent' substitutions in exon 20 of three patients, and two patients had exon 21 variants; a missense variant and a 'silent' substitution. Intronic variants were also found in three patients. Patient 5420 harbored more than one variant in the tumor tissue and patient 5483 harbored more than one somatic variant in the adjacent normal tissue. Although the sample size is small, these preliminary results seem to show a difference in EGFR variants between BRCA1/BRCA2 mutation carriers and non-carriers. Conclusion . EGFR variants found in this study were not the same ones found in lung cancer, but other variants could be significant in breast cancer progression and could possibly represent drug targets for future therapy.
APA, Harvard, Vancouver, ISO, and other styles
28

Manson, Ania Louise. "Modelling the cystic fibrosis RII7H mutation." Thesis, Imperial College London, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.300628.

Full text
APA, Harvard, Vancouver, ISO, and other styles
29

Korejo, Imtiaz Ali. "Adaptive mutation operators for evolutionary algorithms." Thesis, University of Leicester, 2012. http://hdl.handle.net/2381/10315.

Full text
Abstract:
Evolutionary algorithms (EAs) are a class of stochastic search and optimization algorithms that are inspired by principles of natural and biological evolution. Although EAs have been found to be extremely useful in finding solutions to practically intractable problems, they suffer from issues like premature convergence, getting stuck to local optima, and poor stability. Recently, researchers have been considering adaptive EAs to address the aforementioned problems. The core of adaptive EAs is to automatically adjust genetic operators and relevant parameters in order to speed up the convergence process as well as maintaining the population diversity. In this thesis, we investigate adaptive EAs for optimization problems. We study adaptive mutation operators at both population level and gene level for genetic algorithms (GAs), which are a major sub-class of EAs, and investigate their performance based on a number of benchmark optimization problems. An enhancement to standard mutation in GAs, called directed mutation (DM), is investigated in this thesis. The idea is to obtain the statistical information about the fitness of individuals and their distribution within certain regions in the search space. This information is used to move the individuals within the search space using DM. Experimental results show that the DM scheme improves the performance of GAs on various benchmark problems. Furthermore, a multi-population with adaptive mutation approach is proposed to enhance the performance of GAs for multi-modal optimization problems. The main idea is to maintain multi-populations on different peaks to locate multiple optima for multi-modal optimization problems. For each sub-population, an adaptive mutation scheme is considered to avoid the premature convergence as well as accelerating the GA toward promising areas in the search space. Experimental results show that the proposed multi-population with adaptive mutation approach is effective in helping GAs to locate multiple optima for multi-modal optimization problems.
APA, Harvard, Vancouver, ISO, and other styles
30

Sandrock, Kirstin, Ralf Knöfler, Andreas Greinacher, Birgitt Fürll, Sebastian Gerisch, Ulrich Schuler, Siegmund Gehrisch, Anja Busse, and Barbara Zieger. "Novel Mutation in Bernard-Soulier Syndrome." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-136606.

Full text
Abstract:
Background: Bernard-Soulier syndrome (BSS) is a severe congenital bleeding disorder characterized by thrombocytopenia, thrombocytopathy and decreased platelet adhesion. BSS results from genetic alterations of the glycoprotein (GP) Ib/IX/V complex. Methods: We report on a patient demonstrating typical BSS phenotype (thrombocytopenia with giant platelets, bleeding symptoms). However, BSS was not diagnosed until he reached the age of 39 years. Results: Flow cytometry of the patient’s platelets revealed absence of GPIb/IX/V receptor surface expression. In addition, immunofluorescence analysis of patient’s platelets demonstrated very faint staining of GPIX. A novel homozygous deletion comprising 11 nucleotides starting at position 1644 of the GPIX gene was identified using molecular genetic analysis. Conclusions: The novel 11-nucleotide deletion (g.1644_1654del11) was identified as causing the bleeding disorder in the BSS patient. This homozygous deletion includes the last 4 nucleotides of the Kozak sequence as well as the start codon and the following 4 nucleotides of the coding sequence. The Kozak sequence is a region indispensable for the initiation of the protein translation process, thus preventing synthesis of functional GPIX protein in the case of deletion
Hintergrund: Das Bernard-Soulier-Syndrom (BSS) ist eine angeborene Blutungsstörung, die mit Thrombozytopenie, Thrombozytopathie und verminderter Thrombozytenadhäsion assoziiert ist. BSS wird durch genetische Veränderungen des Glykoprotein(GP)-Ib/IX/V-Komplexes verursacht. Methoden: Wir berichten über einen Patienten mit typischem BSS-Phänotyp (Thrombozytopenie mit Riesenthrombozyten, Blutungssymptome). Dennoch wurde die Diagnose BSS erst im Alter von 39 Jahren gestellt. Ergebnisse: Die Durchflusszytometrie der Thrombozyten des Patienten ergab eine fehlende Oberflächenexpression des GPIb/IX/V-Rezeptors. Zusätzlich zeigten Immunfluoreszenz-Analysen der Thrombozyten eine nur sehr schwache Anfärbung von GPIX. In der molekulargenetischen Analyse wurde eine noch nicht bekannte homozygote Deletion von 11 Nukleotiden (beginnend an Position 1644 im GPIX-Gen) identifiziert. Schlussfolgerungen: Diese neue Deletion von 11 Nukleotiden (g.1644_1654del11) wurde als Ursache für die vermehrte Blutungsneigung bei dem BSS-Patienten identifiziert. Von der homozygoten Deletion betroffen sind die letzten 4 Nukleotide der Kozak-Sequenz sowie das Startkodon und weitere 4 Nukleotide des kodierenden Bereichs. Die Kozak-Sequenz ist unerlässlich für die Initiation der Translation in der Proteinbiosynthese, so dass die bei dem Patienten nachgewiesene Deletion die Synthese des funktionellen GPIX-Proteins verhindert
Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich
APA, Harvard, Vancouver, ISO, and other styles
31

Tabaries, Sébastien. "Gène Hoxa5 : régulation et mutation conditionnelle." Thesis, Université Laval, 2006. http://www.theses.ulaval.ca/2006/24020/24020.pdf.

Full text
APA, Harvard, Vancouver, ISO, and other styles
32

Irvine, Alan David. "Mutation analysis in human keratin diseases." Thesis, Queen's University Belfast, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.268237.

Full text
APA, Harvard, Vancouver, ISO, and other styles
33

Wrighton, Katharine Helen. "TP53 mutation and cell cycle regulation." Thesis, King's College London (University of London), 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.405794.

Full text
APA, Harvard, Vancouver, ISO, and other styles
34

Wu, F. "Mutation-based genetic improvement of software." Thesis, University College London (University of London), 2017. http://discovery.ucl.ac.uk/1561361/.

Full text
Abstract:
Genetic Improvement (GI) of software is a recent field that has drawn much attention from Software Engineering researchers. It aims to use search techniques to automatically modify and improve existing software. The drawback in previous GI approaches is scalability of these approaches, due to the large search space formed by the code base in real-world systems. To overcome the scalability challenge, more recent studies have confined the granularity of code modification at the statement level and applied a prior sensitivity analysis to further reduce the search space. However, some software improvements may require code changes at a finer level of granularity. This thesis demonstrates that, by combining with Mutation Testing techniques, GI can operate at this finer granularity while preserving scalability. The thesis applies Mutation Operators to automatically modify the source code of the target software. After a prior sensitivity analysis on First Order Mutants, "deep" (previously unavailable) parameters are exposed from the most sensitive locations, followed by a bi-objective optimisation process to fine tune them together with existing ("shallow") parameters. The objective is to improve both time and memory resources required by the computation. Since this approach relies on the selection of Mutation Operators and traditional Mutation Operators are not concerned with memory performance, the thesis proposes and evaluates Memory Mutation Operators in the Mutation Testing context. Using both traditional and Memory Mutation Operators, the thesis further seeks to improve the target software by searching for Higher Order Mutants (HOMs). The thesis presents the result of a code analysis study, which reveals that, among all the code modifications that contribute to the improvement, more than half of them require a finer control of the code, which our approach is better at than previous GI approaches.
APA, Harvard, Vancouver, ISO, and other styles
35

Abu, Hashish Nabil. "Mutation analysis of dynamically typed programs." Thesis, University of Hull, 2013. http://hydra.hull.ac.uk/resources/hull:8444.

Full text
Abstract:
The increasing use of dynamically typed programming languages brings a new challenge to software testing. In these languages, types are not checked at compile-time. Type errors must be found by testing and in general, programs written in these languages require additional testing compared to statically typed languages. Mutation analysis (or mutation testing) has been shown to be effective in testing statically (or strongly) typed programs. In statically typed programs, the type information is essential to ensure only type-correct mutants are generated. Mutation analysis has not so far been fully used for dynamically typed programs. In dynamically typed programs, at compile-time, the types of the values held in variables are not known. Therefore, it is not clear if a variable should be mutated with number, Boolean, string, or object mutation operators. This thesis investigates and introduces new approaches for the mutation analysis of dynamically typed programs. The first approach is a static approach that employs the static type context of variables to determine, if possible, type information and generate mutants in the manner of traditional mutation analysis. With static mutation there is the danger that the type context does not allow the precise type to be determined and so type-mutations are produced. In a type-mutation, the original and mutant expressions have a different type. These mutants may be too easily killed and if they are then they represent incompetent mutants that do not force the tester to improve the test set. The second approach is designed to avoid type-mutations. This approach requires that the types of variables are discovered. The types of variables are discovered at run-time. Using type information, it is possible to generate only type-correct mutants. This dynamic approach, although more expensive computationally, is more likely to produce high quality, difficult to kill, mutants.
APA, Harvard, Vancouver, ISO, and other styles
36

Gibbs, Mark. "Mutation at a hypervariable mouse minisatellite." Thesis, University of Leicester, 1992. http://hdl.handle.net/2381/34413.

Full text
Abstract:
'Minisatellites' are a class of tandemly repeated sequences ubiquitous to eukaryotic genomes. A subset of minisatellites have been found to be highly variable in tandem repeat copy number. This variability makes such loci highly informative markers for genetic mapping, establishing family relationships in humans and other animals, and individual identification from forensic samples. One highly unstable mouse minisatellite locus, Ms6- hm, has been previously identified in mouse DNA fingerprints by crosshybridization with the human minisatellite probe 33.6. Ms6-hm showed a high germline mutation rate to new length alleles (2.5% per gamete) causing multi-allelism and heterozygosity even within inbred strains. Mice mosaic for cells carrying a non-parental allele in somatic tissue are also seen (2.8% of mice). At reduced stringency Ms6-hm detects other loci, one of which, Hm-2, also appeared to be highly unstable This work describes the characterization of this locus. Hm-2 has been cloned, localized to chromosome 9 using recombinant inbred strains, and sequenced. The repeat sequence, (GGCA)n, is short and the largest Hm-2 alleles can have over 5000 tandem repeats. Like Ms6-hm, Hm-2 shows a high germline mutation rate (3.6% per gamete). The incidence of mosaicism at Hm-2 (20.4% of adult mice) is much greater than at Ms6-hm, however, making Hm-2 an ideal locus for further study of somatic mutation events. Analysis of Hm-2 in embryonic and extra-embryonic tissues has shown that many mutation events occur early in development to produce in some cases divergence in Hm-2 genotype between the embryo and trophoblast. In others, mosaicism was shared between the embryo and trophoblast suggesting that these mutations arose very early in development before the fifth cell division following fertilization. The degree of mosaicism in 60 mosaics has been calculated and comparison of this data with computer simulations suggests that the somatic mutation rate is not constant throughout development but rather that mutations are biased towards the first two cell divisions after fertilization.
APA, Harvard, Vancouver, ISO, and other styles
37

Sandrock, Kirstin, Ralf Knöfler, Andreas Greinacher, Birgitt Fürll, Sebastian Gerisch, Ulrich Schuler, Siegmund Gehrisch, Anja Busse, and Barbara Zieger. "Novel Mutation in Bernard-Soulier Syndrome." Karger, 2010. https://tud.qucosa.de/id/qucosa%3A27717.

Full text
Abstract:
Background: Bernard-Soulier syndrome (BSS) is a severe congenital bleeding disorder characterized by thrombocytopenia, thrombocytopathy and decreased platelet adhesion. BSS results from genetic alterations of the glycoprotein (GP) Ib/IX/V complex. Methods: We report on a patient demonstrating typical BSS phenotype (thrombocytopenia with giant platelets, bleeding symptoms). However, BSS was not diagnosed until he reached the age of 39 years. Results: Flow cytometry of the patient’s platelets revealed absence of GPIb/IX/V receptor surface expression. In addition, immunofluorescence analysis of patient’s platelets demonstrated very faint staining of GPIX. A novel homozygous deletion comprising 11 nucleotides starting at position 1644 of the GPIX gene was identified using molecular genetic analysis. Conclusions: The novel 11-nucleotide deletion (g.1644_1654del11) was identified as causing the bleeding disorder in the BSS patient. This homozygous deletion includes the last 4 nucleotides of the Kozak sequence as well as the start codon and the following 4 nucleotides of the coding sequence. The Kozak sequence is a region indispensable for the initiation of the protein translation process, thus preventing synthesis of functional GPIX protein in the case of deletion.
Hintergrund: Das Bernard-Soulier-Syndrom (BSS) ist eine angeborene Blutungsstörung, die mit Thrombozytopenie, Thrombozytopathie und verminderter Thrombozytenadhäsion assoziiert ist. BSS wird durch genetische Veränderungen des Glykoprotein(GP)-Ib/IX/V-Komplexes verursacht. Methoden: Wir berichten über einen Patienten mit typischem BSS-Phänotyp (Thrombozytopenie mit Riesenthrombozyten, Blutungssymptome). Dennoch wurde die Diagnose BSS erst im Alter von 39 Jahren gestellt. Ergebnisse: Die Durchflusszytometrie der Thrombozyten des Patienten ergab eine fehlende Oberflächenexpression des GPIb/IX/V-Rezeptors. Zusätzlich zeigten Immunfluoreszenz-Analysen der Thrombozyten eine nur sehr schwache Anfärbung von GPIX. In der molekulargenetischen Analyse wurde eine noch nicht bekannte homozygote Deletion von 11 Nukleotiden (beginnend an Position 1644 im GPIX-Gen) identifiziert. Schlussfolgerungen: Diese neue Deletion von 11 Nukleotiden (g.1644_1654del11) wurde als Ursache für die vermehrte Blutungsneigung bei dem BSS-Patienten identifiziert. Von der homozygoten Deletion betroffen sind die letzten 4 Nukleotide der Kozak-Sequenz sowie das Startkodon und weitere 4 Nukleotide des kodierenden Bereichs. Die Kozak-Sequenz ist unerlässlich für die Initiation der Translation in der Proteinbiosynthese, so dass die bei dem Patienten nachgewiesene Deletion die Synthese des funktionellen GPIX-Proteins verhindert.
Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.
APA, Harvard, Vancouver, ISO, and other styles
38

Xia, Xiaoning. "La mutation du système financier chinois." Paris 9, 1989. https://portail.bu.dauphine.fr/fileviewer/index.php?doc=1989PA090010.

Full text
Abstract:
Le système financier chinois a connu une mutation profonde depuis le début de la réforme en 1979. Elle s'est caractérisée par le développement rapide de la monétisation de l'économie, la montée des banques dans le système financier et la création des marchés financiers et monétaires. L'introduction de l'économie du marché entraine un déclin du rôle du plan et par conséquent une perte d'influence du ministère des finances. Mais, à l'heure actuelle, le rôle des institutions financières et des banques dans l'orientation des ressources est encore faible en raison de leur faible participation aux investissements à long terme et du maintien de l'importance du plan dans le financement des grands projets. Les résultats de la politique monétaire de la banque populaire sont encore médiocres. La raison en est que les moyens traditionnels administratifs ne sont plus valables et que les instruments économiques (taux d'intérêt, réserves obligatoires etc. ) ne peuvent pas fonctionner de manière satisfaisante dans une économie de marché encore partielle. Du fait de la politique d'ouverture, le système financier doit s'adapter aux besoins d'une économie qui s'intègre de plus en plus à l'économie mondiale. Dans ce sens, la banque de Chine continue son internationalisation avec succès. Les variables comme les taux de change et les taux d'intérêt ne sont plus indépendantes de l'environnement international en raison de l'arrivée d'investisseurs étrangers les capitaux étrangers jouent un rôle déterminant dans les transferts de technologies. Cependant on s'aperçoit que les banques étrangères qui s'implantent en Chine se trouvent en face d'un marché certes très alléchant mais difficile à pénétrer à court terme. Hong-Kong devrait continuer à jouer son rôle essentiel pour l'économie chinoise, en particulier par l'apport de devises, mais ce rôle ne pourra être garanti que si on préserve le dynamisme de l'industrie locale ainsi que la convertibilité de sa monnaie
The economic reform which was started in 1979 has had changes in the Chinese financial system. The changements can be summarized as the monetization of Chinese economy, the more important role of banks and financial institutions in the national saving-investment and the creation of capital markets. The introduction of market mechanism reduces the importance of the plan and causes the influential decline of the ministry of finance. Chinese banks and financial institutions have an increasing role in the national saving-investment, but the banks still limited influence in long term investment because of the domination of real bill principle in banking system. The people's bank of china tries to implement an active monetary policy but the performance is poor due to the fact that the bank tries to run an economy which doesn't have a perfect market mechanism, with market instruments such as required reserves and interest rates. With the open-door policy, Chinese financial system tries to meet the new needs of the economy. The bank of china continues its successful internationalization strategy. The Chinese economy is not any more independent of the world economy. The economic variables such as exchange rate and interest rate are now sensible to international environment due to the arrival of foreign investors. Foreign capitals are the key factors in the technology transfer from western countries to china. Meanwhile, the foreign banks find that Chinese commercial credit market to be very difficult to enter though promising in long term. Hong-Kong is a very important hard currency source which contributes to Chinese balance of payment. But its financing role could only be preserved in condition that its economic dynamic is not damaged
APA, Harvard, Vancouver, ISO, and other styles
39

Weil-Sierpinski, Batyah. "L'intervention d'humanité : un concept en mutation." Montpellier 1, 1995. http://www.theses.fr/1995MON10062.

Full text
Abstract:
L'intervention d'humanite est un concept qui s'est developpe au cours du 19eme siecle. Ce concept a ete concu differemment selon qu'il etait envisage par les etats ou par des autuers de droit international. Il s'est maintenu en droit international contemporain tout en se modifiant quant a son contenu et a ses modalites, la presentation etatique et doctrinale se rapprochant. Il a notamment ete envisage en liaison avec la protection des nationaux a l'etranger pratiquee avec la force armee. Le concept "intervention d'humanite" a ete reactive par l'emergence recente d'une forme d'assistance humanitaire. On peut considerer que l'intervention d'humanite est un concept en mutation mais quelque soit cette mutation, il faut envisager l'analyse de ce concept en fonction du droit international en vigueur. L'etude de l'intervention d'humanite stricto senso, de l'intervention d'humanite-protection des nationaux et de l'assistance humanitaire revele des mutations propres a l'evolution de la societe internationale
Humanitarian intervention is a concept that was developped in the nineteenth century. This concept was formed differently according as it was conceived by the states or authors of international law. It remained in contemporary international law but its content and modalities have changed, state presentation coming close to doctrinal presentation. It was especially envisaged in connection with rescuing nationales abroad through military coercion. The concept of humanitarian intervention was reactived by the latest emergence of a type of humanitarian assistance. It is possible to consider that humanitarian intervention is a changing concept but whatever this change is, this concept must be analysed according to nowadays international law. The study of humanitarian intervention stricto senso, humanitarian intervention rescuing national abroad and humanitarian assistnce shows typical changes in the international society evolution
APA, Harvard, Vancouver, ISO, and other styles
40

Tabariès, Sébastien. "Gène Hoxa5 : régulation et mutation conditionnelle." Doctoral thesis, Université Laval, 2006. http://hdl.handle.net/20.500.11794/18482.

Full text
APA, Harvard, Vancouver, ISO, and other styles
41

Dinda, Stephen B. "Predicting RNA Mutation Using 3D Structure." Bowling Green State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1321280932.

Full text
APA, Harvard, Vancouver, ISO, and other styles
42

Brihn, Lesil E. "POSITIONAL CLONING OF THE DISORGANIZATION MUTATION." Case Western Reserve University School of Graduate Studies / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=case1189146887.

Full text
APA, Harvard, Vancouver, ISO, and other styles
43

Zhong, Qi. "Hyperphosphorylation and Mutation Enhance Tau Aggregation." The Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=osu1228235966.

Full text
APA, Harvard, Vancouver, ISO, and other styles
44

Fischer, Jared Michael. "Mouse Models of Mutation in vivo." University of Cincinnati / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1227214862.

Full text
APA, Harvard, Vancouver, ISO, and other styles
45

Verlhac, Jérôme. "La mutation européenne du droit associatif." Limoges, 2011. http://www.theses.fr/2011LIMO1002.

Full text
Abstract:
Le droit associatif est au carrefour des grandes libertés. Il est exercé sans l'épuiser dans le droit de s'associer. Son omniprécense traduit un moyen adapté, parfois le seul, de contourner l'inadéquation d'échelle entre les capacités de l'individu et les exigences nouvelles de son environnment. Cette observation du renfort opportun du droit assocaitif révèle une mutation à double détente. D'une part, le glissement du cadre national à l'espace européen entraîne un changement de références juridiques, d'internes elles deviennent communes. D'autre part, l'exercice du droit associatif participe à un boulversement sociétal en accompagnant l'émergence d'un nouvel acteur impliqué démocratiquzement, et concerné économiquement. La mutation du droit associatif le pla ce à la convergence des droits européens en devenant l'unité de référence et un moyen de compensation des lacunes conjoncturelles de la construction européenne
The associative law is at the crossroads of the great freedoms. It is done without exhausting the right to associate. His omnipresence is a way adapted, sometimes the only way to overcome the mismatch of scale between the caâbilities of the individual and the new demands of its environment. This observation of timely reinforcement of assiation law reveals a double mutation trigger. On the one hand, the shift from natioanl to the european results in a change of legal references, interns they become common. On the other hand, the right os associations involved in societal upheaval accompanying the emergence of a new player involved democratically and economically relevant. Mutation of the associative law up the convergence of European rights by becoming the unit of reference and a meas to offset cyclical weakness of european integration
APA, Harvard, Vancouver, ISO, and other styles
46

Urteaga, Eguzki. "Les journalistes locaux : mutation d'une profession." Bordeaux 2, 2000. http://www.theses.fr/2000BOR21819.

Full text
APA, Harvard, Vancouver, ISO, and other styles
47

Aston, Elizabeth Jane. "Critical mutation rates in small populations." Thesis, Keele University, 2014. http://eprints.keele.ac.uk/1321/.

Full text
Abstract:
Mutation introduces change at the sequence level. There is a critical mutation rate above which changes occur too frequently for natural selection to maintain the population's genetic makeup. This thesis examines the relationship between this critical mutation rate and the number of individuals in the adapting population. It presents an algorithmic method capable of providing widely applicable results in haploid and diploid populations, and varies this method against analytical models for the error threshold. Use of the method led to the discovery of an exponential relationship between the critical mutation rate and population size, particularly strong in small populations with 100 individuals or less, contradicting the existing idea that critical mutation rate and population size are independent. The critical mutation rate (and error threshold) were found to be lower in diploids due to differences in recombination. Analysis of the survival-of-the-fittest to survival-of-the-flattest transition enabled improvement of existing definitions of the critical mutation rate. Development of a faster algorithm capable of running experiments with parameter values within the range found in nature began the process of bridging the gap between artificial and biological evolution. A link was established between the exponential model and natural mutation rates. Increasing the gene length by a factor of 10 was found to decrease both the critical mutation rate and error threshold by an order of magnitude. Natural mutation rates lie below these values, although further work is required to establish any trend. A potential link has been established between the critical mutation rate, error threshold, and optimal mutation rate control theory. Future work may develop the algorithmic method to include more complex features of biological populations, and go on to determine the effect the exponential model can have on population extinction, recovery, and conservation.
APA, Harvard, Vancouver, ISO, and other styles
48

Wright, Christopher. "Mutation analysis of relational database schemas." Thesis, University of Sheffield, 2015. http://etheses.whiterose.ac.uk/12059/.

Full text
Abstract:
The schema is the key artefact used to describe the structure of a relational database, specifying how data will be stored and the integrity constraints used to ensure it is valid. It is therefore surprising that to date little work has addressed the problem of schema testing, which aims to identify mistakes in the schema early in software development. Failure to do so may lead to critical faults, which may cause data loss or degradation of data quality, remaining undetected until later when they will prove much more costly to fix. This thesis explores how mutation analysis – a technique commonly used in software testing to evaluate test suite quality – can be applied to evaluate data generated to exercise the integrity constraints of a relational database schema. By injecting faults into the constraints, modelling both faults of omission and commission, this enables the fault-finding capability of test suites generated by different techniques to be compared. This is essential to empirically evaluate further schema testing research, providing a means of assessing the effectiveness of proposed techniques. To mutate the integrity constraints of a schema, a collection of novel mutation operators are proposed and implementation described. These allow an empirical evaluation of an existing data generation approach, demonstrating the effectiveness of the mutation analysis technique and identifying a configuration that killed 94% of mutants on average. Cost-effective algorithms for automatically removing equivalent mutants and other ineffective mutants are then proposed and evaluated, revealing a third of mutation scores to be mutation adequate and reducing time taken by an average of 7%. Finally, the execution cost problem is confronted, with a range of optimisation strategies being applied that consistently improve efficiency, reducing the time taken by several hours in the best case and as high as 99% on average for one DBMS.
APA, Harvard, Vancouver, ISO, and other styles
49

Thomas, E. M. "Aspects of gender mutation in Welsh." Thesis, Bangor University, 2001. https://research.bangor.ac.uk/portal/en/theses/aspects-of-gender-mutation-in-welsh(9c4dcb8d-59fa-46be-9048-c9626a09b146).html.

Full text
Abstract:
Research on the acquisition of grammatical gender has shown that for many languages, children gain an early command of gender. However, often in these languages gender marking is quite overt and provides a clear one-to-one correspondence between a marker and the gender encoded. In Welsh, gender marking is more complex. Gender is marked by mutations, a set of morphophonological changes that affect the initial consonants of words, and the mapping between mutation and gender is quite opaque. Two mutation types are used in part to mark feminine gender: both feminine nouns modified by the definite article and adjectives following feminine nouns undergo Soft Mutation, and the feminine gender of the possessive adjective ei is marked by Aspirate Mutation on the modified noun. The four studied in this thesis examined children's productive command of gender as expressed in the mutation of nouns modified by the definite article, of adjectives modifying nouns, and of nouns modified by the homonymic feminine and masculine possessive adjective. Mutation in non-gendered contexts was also examined. Subjects were 4- to 9 1I2-year-old children from North Wales. First, a seminaturalistic study was conducted to obtain knowledge about children's ability with gender marking. A Cloze procedure was also used to elicit children's production of masculine and feminine forms, both real words and nonsense forms, in a variety of linguistic contexts. Some of these contexts provided cues to gender status, some did not. The data obtained indicated that the acquisition of the Welsh gender system is a drawn-out process, and children have not mastered the system even by 9 112years of age. In addition, children become proficient in marking feminine nouns modified by the definite article and adjectives modifying feminine nouns before they do so on nouns modified by feminine ei. Results suggest that when a language has a complex gender system that is marked by opaque morpho-phonological processes the course of development is protracted and variable.
APA, Harvard, Vancouver, ISO, and other styles
50

Firth, James Dawrant. "A study of a dominant suppressor of the purple eye-color mutant in Drosophila melanogaster." Thesis, University of British Columbia, 1985. http://hdl.handle.net/2429/24663.

Full text
Abstract:
The subject of this study is a new dominant suppressor mutation Su(pr) which acts on the purple eye-colour mutant (pr) of Drosophila a melanogaster. The Induction of Su (pr) was originally associated with the synthesis of a compound-2R chromosome In SD72/cn bw females. The suppression of p_ was first observed in combination with a homologous pr bearing compound-2L chromosome. Suppressed-pr flies appeared to have a fully wild eye phenotype. The intention of this study was to determine the chromosomal constitution necessary for Su(pr) induction, and to map the suppressor site. To do this, many compound-2R chromosomes were synthesized from several combinations of standard seconds. It was found that SD72 must be present to produce a suppressing compound-2R. The SD72 second carries a pericentric inversion that results in a duplication of 2L heterochromatIn, and an associated deficiency of 2R heterochromatin in the compound-2R S u (p r) chromosome. Suppression, therefore, Is associated with the pericentric inversion found only on SD72. The role of this segmental aneuploidy was studied by detaching several C(2L)pr: C(2R)SD72/,cn bw suppressed strains such that both arms of the Su(pr) compound autosome were recovered independently and established in standard strains. Suppressing and non-suppressing detachment products were recovered with a frequency that varied according to the compound-2R Su(pr) strain from which they were derived. The chromosome mechanics involved in the process of C(2R)SD72/cn bw formation and subsequent detachment implicates alterations to a segment of proxlmial 2R heterochromatin from SD72 in Su(pr) Induction. Loss of Su(pr) in the detachment process correlates predominantly with deletions generated In 2R heterochromatIn. Recombination mapping relative to the two visible heterochromatic markers, Iight and rolled, revealed that Su(pr) Iies to the left of rolIed. SpectrophotometrIc measurements of eye pigments revealed that suppressed-pr and suppressed-pru bw flies had pigment levels that exceeded the wild type. The lethal allele prc4. was not found to be suppressible.
Science, Faculty of
Zoology, Department of
Graduate
APA, Harvard, Vancouver, ISO, and other styles
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography