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Expression analysis of the regenerating utricle sensory epithelia : from microarrays to parsing pathwaysHawkins, Raymond David. January 2005 (has links) (PDF)
Thesis (Ph. D.) -- University of Texas Southwestern Medical Center at Dallas, 2005. / Vita. Bibliography: 197-219.
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Peptide nucleic acid (PNA) hybridization to nucleic acid targetsNulf, Christopher J. January 2004 (has links) (PDF)
Thesis (Ph. D.) -- University of Texas Southwestern Medical Center at Dallas, 2004. / Vita. Bibliography: References located at the end of each chapter.
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Identification of candidate genes that influence sex hormone dependent disease phenotypes in mouse lupus /Gubbels, Melanie Rae. January 2005 (has links)
Thesis (Ph.D. in Human Medical Genetics) -- University of Colorado at Denver and Health Sciences Center, 2005. / Typescript. Includes bibliographical references (leaves 104-138). Free to UCDHSC affiliates. Online version available via ProQuest Digital Dissertations;
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European labour market trajectories before and during the 2008 financial crisis : national, regional and individual variationDima, Dafni January 2018 (has links)
Since 2008 Europe has been in crisis, a financial and debt crisis that spread from the U.S. to all European countries. This thesis aims to provide evidence on the consequences of the crisis for individuals’ labour market outcomes across different countries and regions of Europe and to analyse how the recession has differentially affected sub-groups of the European population. Through the analysis of the longitudinal component of the European Union Statistics on Income and Living Conditions (EU-SILC) dataset, the project sheds light on the labour market trajectories of more than 20,000 Europeans across 11 European countries and 41 regions, before and during the 2008 financial crisis (2005-2012). Sequence and cluster analysis are used to investigate the heterogeneity of individual labour market trajectories across countries and time, while multilevel models are used to study regional labour markets during the years in crisis. The concept of transitional labour markets, as well as theories of labour market segmentation, job competition and job mobility, provide the theoretical framework for this research. The empirical findings show that during the financial crisis, labour market trajectories appear more turbulent and fragmented for the already disadvantaged sub-groups, namely women, younger workers and low educated workers. Furthermore, during the Great recession, an increase in unemployment among men confirms the sectoral profile of the crisis, which hit harder the male-dominated sectors of construction and industry. At the same time, a decrease in inactivity among women is consistent with the added worker effect, according to which women in periods of economic hardship are pushed towards labour market activity in order to contribute to the household income. Countries with weak economies and underperforming labour markets prior to the crisis, such as Greece and Italy, unsurprisingly experienced a deep and persistent crisis, while countries with stronger economies and more inclusive labour markets, such as Denmark and Sweden, managed to survive the crisis with less social harm. The institutional context of the countries offering high chances of employment even during the financial crisis, such as the Nordic countries, lies on the flexicurity of their labour markets. Indeed, flexible labour markets with the use of reduced working-time schemes, i.e. part-time forms of employment, contained unemployment during the financial shock. However, we need to be cautious about flexibility without security or partial deregulation of the markets, implemented in southern European countries, because during the crisis such policies led to further labour market segmentation and thus an increase in employment inequalities. Finally, the region of residence matters in employment outcomes, almost as much as the country of residence. In fact, from the regional analysis of individual employment outcomes during the years of the crisis, an uneven distribution of labour is detected even within the national borders. Summing up, the European crisis should be considered as the sum of national and regional crises.
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Expressão gênica diferencial do câncer de mama de pacientes pós-menopausadas responsivas e não-responsivas ao efeito antiproliferativo da vitamina D / Breast cancer gene expression profile in post-menopausal patients responsive or non-responsive to the antiproliferative effect of vitamin DYuri Nagamine Urata 30 August 2010 (has links)
Baixos níveis séricos de 25(OH)D3 e 1,25(OH)2D3 (calcitriol) podem estar associados à incidência e prognóstico do câncer de mama. Além disso, vários estudos indicam que a vitamina D tenha um efeito antiproliferativo em linhagens celulares de câncer de mama expostas a concentrações supra-fisiológicas de calcitriol (1,25(OH)2D3, 100nM). A suplementação com vitamina D é indicada a mulheres pós-menopausadas para prevenção de osteoporose e observamos previamente que a suplementação de calcitirol a pacientes pós-menopausadas com câncer de mama causa redução do índice proliferativo tumoral. Entretanto, não há estudos até o momento que avaliam o efeito da vitamina D na expressão gênica global in vivo. Incluímos 31 pacientes pós-menopausadas com câncer de mama. Estas pacientes realizaram suplementação com calcitriol (0,5g/dia, dose indicada para prevenção de osteoporose) por um curto período de tempo (mediana de 32 dias). A amostra tumoral foi coletada por ocasião da biópsia (présuplementação) e da ressecção tumoral (pós-suplementação). Os perfis de expressão gênica de 16 pacientes foram analisados a partir de 100ng de RNA total no gene chip U133 Plus 2.0 Affymetrix. Observamos redução na expressão de Ki-67 após a suplementação. Dentre os genes diferencialmente expressos encontram-se EGR1, FOS, DUSP1, MMP12 e RGS1, os quais foram mais expressos em amostras pós-suplementadas. Genes modulados pela vitamina D estão associados à resposta inflamatória e à membrana. Nossos resultados indicam que a suplementação com vitamina D reduz o índice de proliferação tumoral, sendo a mesma envolvida em vias importantes na regulação da resposta inflamatória / Low 25(OH)2D3 or 1,25(OH)2D3 serum levels may be associated with breast cancer incidence and prognosis. Additionally, the antiproliferative effects of vitamin D are observed in breast cancer cell lines exposed to phamacological doses of calcitriol (1,25(OH)2D3, 100nM). Vitamin D supplementation is indicated for post-menopausal women to prevent osteoporosis and a previous study from our group observed a reduced tumor proliferative index after calcitriol supplementation on post menopausal breast cancer patients. However, there is no study that verifies the effect of vitamin D on gene expression profile in vivo so far. Thirty one post menopausal breast cancer patients were included on our analysis. They were supplemented with calcitriol after tumor biopsy (0.50g/day, indicated dose for osteoporosis prevention) for a short period of time (median 32 days). Tumor samples were collected during biopsy (before supplementation) and breast surgery (after supplementation). Gene expression profile of 16 patients was analyzed using the U133 Plus 2.0 Affymetrix Gene Chips from 100ng of total RNA. After supplementation, a reduced expression of Ki-67 was observed. Among the differentially expressed genes, EGR1, FOS, DUSP1, MMP12 and RGS1 were upregulated after calcitriol supplementation. Differentially expressed genes were involved in inflammatory response or were associated with the membrane. Our results indicate that calcitriol supplementation diminish tumor proliferation index regulating inflammatory pathways .
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Mönster som leder till sjukfrånvaro : Sekvensanalys på longitudinella data / Patterns that lead to sick leave : Sequence analysis on longitudinal dataJesperson, Sara, Johansson, Sara January 2017 (has links)
Sjukfrånvaro innebär en kostnad för både arbetsgivare och arbetstagare. För en anonym fullgrossist är detta ett problem på en av deras lagerlokaler, där sjukfrånvaron är hög. Uppsatsen syftar till att identifiera intressanta mönster över tid som leder till sjukfrånvaro genom att analysera data från företagets lönesystem och tidssystem. Datamaterialet är longitudinellt och för att upptäcka mönster som leder till sjukfrånvaro används sekvensanalys. För att generera de sekventiella mönstren används algoritmen cSPADE då den möjliggör att tidsbegränsningar kan anges för sekvenserna. Relevansen hos de genererade sekvenserna utvärderas med tre intressemått: support, konfidens och lift. Tre separata analyser genomförs där olika antal variabler används, beroende på om de förändras över tid eller har ett konstant värde, och för dessa analyser aggregeras data veckovis. De vanligaste händelserna som leder till sjukfrånvaro hos expeditörer är olika anställningstider, kön och födelseår. Några dagars sjukfrånvaro under en vecka, det vill säga mellan 8 och 40 timmar, är mer förekommande bland expeditörerna jämfört med kortare respektive längre sjukfrånvaro. Det går att konstatera att mönster med tidigare sjukfrånvaro ofta leder till fortsatt sjukfrånvaro. Uppsatsen belyser även de problem som uppstår inom sekvensanalys, till exempel att konstanta variabler överskuggar de icke-konstanta variablerna i de genererade sekvenserna. Detta händer när variabler som förändras över tiden används i kombination med variabler som har konstanta värden, något som kan förekomma i longitudinella datamaterial. / Absence due to sickness results in a cost to both employers and employees. For an unnamed wholesaler this is a problem at one of their warehouses, where the rate of sick leave is high. The aim of this thesis is to identify interesting patterns over time that lead to sick leave by analyzing data from the company's payroll system and their attendance system. The data is longitudinal and to detect the patterns that lead to sick leave, sequence analysis is used. To generate the sequential patterns the algorithm cSPADE is used since it allows time constraints to be specified for the sequences. The relevance of the generated sequences is evaluated with three interest measures: support, confidence and lift. Three separate analyses are performed where different variables are used, depending on whether they change over time or have a constant value, and for these analyses the data is aggregated weekly. The most common events that lead to sick leave for the employees are different duration of employment, gender and birth year. A few days sick leave during a week, namely between 8 and 40 hours, is more common among the employees compared to shorter and longer sick leave. It can be noted that the pattern of previous sick leave usually leads to continued sick leave. The thesis also highlights the problems that arise in sequence analysis, for example that the constant variables overshadow the non-constant variables in the resulting sequences. This happens when variables that change over time are used in combination with variables that have a constant value, which may occur in longitudinal data.
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Rodinná a pracovní uspořádání v kontextu společenských změn v České republice po roce 1989. Proměny rodinných a pracovních startů / Family and work arrangements in the context of social changes in the Czech Republic after 1989. Transformations in family and professional startsChaloupková, Jana January 2011 (has links)
Charles University in Prague Faculty of Philosophy and Arts Department of Sociology Study Program: Sociology Family and work arrangements in the context of social changes in the Czech Republic after 1989. Transformations in family and professional starts Mgr. Jana Chaloupková Supervisor: PhDr. Dana Hamplová, Ph.D. 2011 Dissertation abstract This dissertation explores the changes in professional and family starts of young men and women in the Czech Republic. It compares an early family and work trajectories of persons, who reached adulthood in 1990s and those theirs family and work starts occurred before 1989. Theoretical and methodological background of this study draws upon a holistic approach to the life-course study and a sequence analysis. The empirical analyses focus on three domains: 1) a normative context of family and work starts, 2) the development of variability of family and work starts, 3) analysis of similarity (types) of early family and work trajectories. Using ISSP 2002 data, the analysis deals with a sequence of family and work statuses held between 18 and 35 years of age. The analyses of the normative context show that in most European countries social adulthood is more strongly linked to becoming financially independent than to starting a family. In the Czech society dominates a norm of...
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Photogrammetrische Verfahren zur Risserkennung und -analyse im bautechnischen VersuchswesenLiebold, Frank 20 January 2021 (has links)
Photogrammetrische Methoden gewinnen zunehmend an Bedeutung im bautechnischen Versuchswesen. Die Auswertung von Bildsequenzen ermöglicht eine kontaktlose, flächenhafte, hochaufgelöste und hochgenaue Veränderungsdetektion von Oberflächen in der Materialprüfung und Bauwerksüberwachung. Diese Arbeit behandelt einige Aspekte der Deformationsanalyse auf Basis von Bildsequenzen mit Hilfe triangulierter Verschiebungsfelder. Zunächst wird auf Untersuchungen zu Deformationen ebener Objektoberflächen, die mit monokularen Bildsequenzen beobachtet wurden, eingegangen. Im weiteren Verlauf wird auf Stereobildsequenzen übergegangen, die Deformationsmessungen für beliebige Oberflächen erlauben.
Im ersten Teil der Arbeit wird gezeigt, wie Verschiebungsfelder in monokularen Bildsequenzen bestimmt werden können. Die Bildpunkte, an welche die Verschiebungen geknüpft sind, werden zu einem Dreiecksnetz trianguliert. Jedes einzelne Dreieck wird auf Änderungen zu der Referenzepoche, die als die erste Epoche ohne jegliche Deformation definiert ist, untersucht. Ein gängiges Verfahren zur Analyse solcher Veränderungen ist die Berechnung von Hauptdehnungen für jedes Dreieck. Schwellwerte können zur Erkennung deformierter Bereiche und die farbkodierte Darstellung der Hauptdehnungen für eine visuelle Betrachtung genutzt werden.
In den räumlich verteilten Hauptdehnungen sowie im zeitlichen Ablauf treten Rauscheffekte auf. Deshalb werden verschiedene Filtermethoden zur Rauschunterdrückung untersucht. Dabei kommt ein Filter zum Einsatz, der gleichzeitig in der räumlichen sowie der zeitlichen Dimension filtert. Es werden aber auch Filter untersucht, die in beiden Dimensionen getrennt filtern.
Aus den Hauptdehnungen können nicht direkt Rissbreiten abgeleitet werden. Diese spielen für die Materialprüfung im Bauwesen allerdings eine wichtige Rolle, weswegen sich diese Arbeit auch mit der Berechnung von Rissbreiten in Dreiecksnetzen befasst. Als deformierte Dreiecke werden diejenigen detektiert, deren Hauptdehnung einen Schwellwert überschreiten. Für diese Kandidaten werden im Folgenden Rissbreiten bestimmt. Drei verschiedene Verfahren für die Ermittlung von Rissbreiten werden vorgestellt und verglichen.
Die Dehnbarkeit faserbewehrter Komposite, die unter anderem zur Verstärkung von Mauern und anderen Bauwerken verwendet werden, wird bei Belastung durch die Bildung multipler Rissstrukturen gewährleistet. Auf Grund dessen widmet sich ein weiterer Teil der Dissertation der Auswertung multipler Rissstrukturen. Hierzu werden dichte Verschiebungsfelder berechnet. Dann wird zunächst eine Auswahl der verfolgten Punkte genutzt, um ein grobes Dreiecksnetz zu generieren. Deformierte Dreiecke der ausgedünnten triangulierten Punktmenge werden mit dem Betrag des relativen Translationsvektors, der als Deformationsmaß eingeführt wird, detektiert. Eine iterative Verdichtung des Dreiecknetzes in deformierten Bereichen ermöglicht die Auswertung enger Rissmuster. Zudem erlaubt eine Ausgleichung, dass nicht-triangulierte Punkte des dichten Verschiebungsfeldes in die Rissbreitenberechnung einbezogen werden können.
Ein weiterer Bestandteil der Arbeit ist die Betrachtung unebener Oberflächen, die mit Stereokamerasystemen beobachtet werden. Dazu werden die Algorithmen für die zweidimensionale Auswertung entsprechend übertragen und erweitert. Auf Basis von Verschiebungsfeldern dreidimensionaler Punkte wird auch hier ein Dreiecksnetz zur Änderungsdetektion genutzt.
So wird am Beispiel von dynamischen Dehnungstests an zylindrischen Probekörpern ein Algorithmus zur Rissbreitenmessung auf nicht ebenen Oberflächen vorgestellt. Dabei wird angenommen, dass die Deformationen ausschließlich tangential zur Oberfläche auftreten. Dies erlaubt die Transformation (Kongruenzabbildung) der Dreiecke in einen zweidimensionalen Raum und auch eine zweidimensionale Auswertung.
Außerdem wird eine Methode zur Berechnung des dreidimensionalen Rissöffnungsvektors präsentiert. Dieses Verfahren ist eine Erweiterung zum vorhergehenden Algorithmus und erlaubt zudem die Vermessung vertikaler Deformationen. Deformierte Dreiecke im triangulierten dreidimensionalen Verschiebungsfeld werden mit Hilfe des zweidimensionalen Relativtranslationsvektorbetrags der in den zweidimensionalen Raum transformierten Dreiecke detektiert. Anschließend folgt für alle deformierten Dreiecke durch Hinzunahme mindestens eines undeformierten Nachbardreiecks die Berechnung eines dreidimensionalen relativen Translationsvektors, mit Hilfe dessen die Komponenten des Rissöffnungsvektors ermittelt werden.:Kurzfassung iii
Abstract v
1. Einführung 1
1.1. Struktur der Arbeit 1
1.2. Motivation 2
1.3. Verwandte Arbeiten 4
1.4. Ziele der Arbeit 7
2. Photogrammetrische Deformationsmessung in monokularen Bildsequenzen 8
2.1. Filtermethoden in Dreiecksnetzen 9
2.2. Rissbreitenberechnung mit Hilfe von Dreiecksnetzen 19
2.3. Strategie zur Rissbreitenmessung für multiple Rissstrukturen 29
3. Photogrammetrische Deformationsmessung in Stereobildsequenzen 50
3.1. Rissbreitenberechnung für tangentiale Deformationen auf nicht ebenen
Oberflächen mit gegebenem 3D-Verschiebungsfeld 51
3.2. Berechnung des dreidimensionalen Rissöffnungsvektors bei gegebenem
3D-Verschiebungsfeld 59
4. Diskussion 70
5. Ausblick 77
5.1. Bestimmung der Anzahl der Risse 77
5.2. Rissspitzenbestimmung und -verfolgung 78
5.3. Anwendung der entwickelten Algorithmen auf Voxeldaten 78
5.4. Modellerweiterung durch Relativrotation 82
5.5. Genauigkeitssteigerungen für die Rissposition 82
5.6 Verbesserung der Rissnormalenschätzung 82
Literaturverzeichnis 83
Abkürzungsverzeichnis 89
Tabellenverzeichnis 90
Abbildungsverzeichnis 90 / Photogrammetric methods are gaining importance in civil engineering material testing and structural health monitoring. The analysis of image sequences ensures an extensive change detection of surfaces with a high spatial resolution and a high accuracy. This thesis deals with some aspects of deformation analysis based on image sequences and triangulated displacement fields. At the beginning, the examination of planar surfaces of specimens observed with monocular image sequences is considered. Later, a transition to stereo image sequences is given because they allow a deformation measurement of arbitrary surfaces.
The first part of the thesis shows how to derive displacement fields from monocular image sequences. The matching points corresponding to the displacements are triangulated into a mesh. Each triangle is compared to the reference epoch which is defined as the first time epoch under zero load without any deformation. As a current method, principal strains are used to detect deformations. Thresholds can be used to find deformed areas. In addition, color-coded maps of the principal strains are helpful for a visual detection.
In the field of the principal strains, noise effects appear in the spatial as well as in the temporal domain. Therefore, different filter methods are applied to reduce noise. In addition to filter techniques that are applied independently in the time and the spatial domain, a combined spatio-temporal filter is tested.
Crack widths cannot be derived directly from principal strains but crack widths are an important issue in civil engineering material testing. For this reason, this thesis also gives attention to the computation of crack widths in triangle meshes. The principal strains of the triangles are tested for exceeding a threshold to detect deformed triangles. For the deformed triangles, crack widths are computed. Three different methods for the crack width determination are presented and compared.
Multiple cracking ensures the ductility of loaded fiber-reinforced composites used to strengthen walls among other things. Therefore, another part of the dissertation deals with the photogrammetric analysis of multiple crack patterns. Herein, dense displacement fields are computed. Then, a thinned-out set of points is triangulated into a mesh. For each triangle, the norm of the relative translations vector defined as a new quantity to detect deformations is determined and used to find cracked triangles. The mesh is densified iteratively in deformed areas to ensure an analysis of narrow crack structures. In addition, a least squares algorithm is presented which allows that points of the displacement field, that are not part of the mesh, can be included in the crack width computation.
A further part of the dissertation deals with non-planar surfaces observed with stereo camera systems. The algorithms of the two dimensional analysis are adapted and extended to use them for these applications. These methods are based on three dimensional displacement fields and also use triangle meshes to detect deformed areas.
One algorithm concentrates on the crack width measurement of non-planar surfaces with deformations that are only tangential to the surface. The method is applied on a cylindrical specimen in a dynamic tension test. The assumption that deformations are tangential to the surface allows the transformation of the triangles in the two dimensional space and also a two dimensional analysis.
In addition, an algorithm for the computation of the three dimensional crack opening vectors is presented. This method is an extension to the foregoing algorithm and is capable of measuring vertical deformations. To find deformed triangles in the triangulated three dimensional displacement field, the triangles are transformed in the two dimensional space in a first step. In a second step, the norm of the two dimensional relative translation vector is determined and tested if it exceeds a threshold. In the following, for each deformed triangle, the three dimensional relative translation vector is computed using a undeformed neighbor triangle. At the end, the three dimensional relative translation vectors can be transformed to the crack opening vectors.:Kurzfassung iii
Abstract v
1. Einführung 1
1.1. Struktur der Arbeit 1
1.2. Motivation 2
1.3. Verwandte Arbeiten 4
1.4. Ziele der Arbeit 7
2. Photogrammetrische Deformationsmessung in monokularen Bildsequenzen 8
2.1. Filtermethoden in Dreiecksnetzen 9
2.2. Rissbreitenberechnung mit Hilfe von Dreiecksnetzen 19
2.3. Strategie zur Rissbreitenmessung für multiple Rissstrukturen 29
3. Photogrammetrische Deformationsmessung in Stereobildsequenzen 50
3.1. Rissbreitenberechnung für tangentiale Deformationen auf nicht ebenen
Oberflächen mit gegebenem 3D-Verschiebungsfeld 51
3.2. Berechnung des dreidimensionalen Rissöffnungsvektors bei gegebenem
3D-Verschiebungsfeld 59
4. Diskussion 70
5. Ausblick 77
5.1. Bestimmung der Anzahl der Risse 77
5.2. Rissspitzenbestimmung und -verfolgung 78
5.3. Anwendung der entwickelten Algorithmen auf Voxeldaten 78
5.4. Modellerweiterung durch Relativrotation 82
5.5. Genauigkeitssteigerungen für die Rissposition 82
5.6 Verbesserung der Rissnormalenschätzung 82
Literaturverzeichnis 83
Abkürzungsverzeichnis 89
Tabellenverzeichnis 90
Abbildungsverzeichnis 90
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Nrg1p and Rfg1p in Candida albicans yeast-to-hyphae transitionLacroix, Céline. January 2008 (has links)
No description available.
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A Family-Based Mapping Study of Autosomal Dominant Nonsyndromic Sensorineural Hearing LossGiovanni, Monica A. 12 July 2007 (has links)
No description available.
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