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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
131

Expressão do mRNA do VEGF, FIt-1 e KDR no placentoma, região interplacentomal e corpo lúteo em diferentes fases gestacionais em bovinos clonados e não clonados / Expression of mRNA of the VEGF, Flt-1 and KDR in placentome, interplacentomal areas and gestational corpus luteum in different phases of pregnancy in cloned and non-cloned bovines

Fernando Garbelotti 31 May 2006 (has links)
O VEGF é um fator mitogênico específico de células endoteliais que promove diferenciação celular materno-fetal placentária quando ligado a seus receptores (Flt-1 e KDR). Sua expressão é controlada por mecanismos autócrinos e parácrinos e está associada ao desenvolvimento da placenta. A placenta bovina foi utilizada como modelo de estudo por apresentar a facilidade de se avaliar os componentes do sistema VEGF em diferentes fases gestacionais. Como objetivo este estudo buscou analisar o fator de crescimento vascular endotelial (VEGF) e seus receptores através da técnica de PCR em tempo real no início, meio e fim de gestação. Para tanto, amostras de placentomas, região interplacentomal e corpo lúteo foram coletadas em diferentes fases gestacionais. Foram utilizados placentomas de animais clonados obtidos apenas aos 270 dias de gestação e estas amostras foram comparadas aos animais não clonados na mesma fase. A expressão do VEGF no placentoma apresentou um decréscimo (p < 0.05) no final da gestação (270 dias) em relação à expressão do VEGF aos 90 dias. A expressão do Flt-1 e do KDR na região interplacentomal foi semelhante desde os 45 até 90 dias de gestação e apresentou um aumento significativo (p < 0.05) aos 150 dias. No corpo lúteo gestacional, a expressão do VEGF aos 210 dias foi maior (p ≤ 0.05) em relação a 90 e 150 dias; observou-se também baixa expressão do KDR aos 90 dias de gestação (p < 0.05) em relação aos 210 dias. Pode-se concluir que a regulação da expressão do VEGF variou em relação aos seus receptores nos três tecidos avaliados. Placentomas de bovinos clonados não apresentaram diferenças significativas em relação à expressão do sistema VEGF se comparados aos placentomas de animais não clonados sugerindo ser esta expressão equivalente em placentas de animais clonados que vieram a termo. / The VEGF is a specific endothelial mitogenic factor that promotes feto-maternal cell differentiation in placenta through binding to its receptors (Flt-1 and KDR). Their expression is controlled by autocrine and paracrine mechanisms that are associated to placenta development. The bovine placenta was used in this study as a model due to easiness of evaluation of VEGF system components in different phases of pregnancy. The objective of this study was to analyze the vascular endothelial growth factor (VEGF) and its receptors expression using the real time PCR technique in the beginning, half and end of pregnancy. Furthermore, placentome samples, interplacentomal areas and corpus luteum were collected in different gestational phases for comparative studies. Placentome of cloned animals were analyzed at 270 days of pregnancy and compared to non-cloned animals in the same phase. The expression of VEGF in the placentome presented a decrease of expression (p < 0.05) in the end of the gestation (270 days) in relation to 90 days. The expression of Flt-1 and of KDR in interplacentomal area was similar from 45 to 90 days of pregnancy with a significant increase (p <0.05) observed at 150 days. In the gestational corpus luteum, the expression of VEGF at 210 days was higher (p ≤ 0.05) in comparison to 90 and 150 days. In the same tissue KDR expression at 90 days was lower (p < 0.05) in relation to 210 days. In conclusion the regulation VEGF varied in relation to its receptors expression in all three studied tissues. Cloned placentomes showed no significant differences in VEGF system expression compared to the placentome of non-cloned animals, suggesting there is an equivalent expression in placentas from cloned animals that came to term.
132

Efeitos do VEGF e do bFGF sobre a expressão da aromatase P450 em cultivo de células placentárias provenientes de bovinos clonados e não clonados / VEGF and bFGF effects on P450 aromatase expression of cultivated placental cells from cloned and non-cloned bovines

Liza Margareth Medeiros de Carvalho Sousa 29 June 2007 (has links)
Os fatores de crescimento vascular endotelial (VEGF) e o fibroblástico básico (bFGF) são reguladores importantes do desenvolvimento e função placentária. Os efeitos destes na expressão da enzima esteroidogênica aromatase P450 (P450arom) na placenta bovina em diferentes estágios gestacionais (90 a 270 dias) foram avaliados através de imunocitoquímica. Além disso, comparou-se a influência destes entre células placentárias de bovinos clonados e não clonados aos 270 dias. A aromatase P450 foi localizada exclusivamente no citoplasma das células trofoblásticas gigantes e sua expressão foi menor aos 150 dias de gestação, em relação às demais idades (p<0,05). O VEGF (50 ng/ml) influenciou significativamente a expressão da P450arom aos 150 e 270 dias, enquanto o bFGF (10 ng/ml) foi efetivo em estimular essa expressão particularmente no final da gestação (270 dias). Os dois fatores combinados (bFGF+VEGF) inibiram a expressão da P450arom no terço inicial (90 dias), mas, por outro lado, estimularam-na aos 150 e 270 dias (p<0,05). Nos clones, a expressão da P450arom, nos grupos controle e VEGF, foi semelhante a dos animais não clonados aos 270 dias de gestação, porém, o bFGF e os dois fatores combinados inibiram-na significativamente (p<0,05). Em todos os grupos analisados, a expressão da P450arom apresentou característica ascendente em função dos dias de cultivo, atingindo concentração máxima após 96 horas de incubação. Assim, o presente estudo demonstrou efeitos distintos e estágio-específicos dos fatores de crescimento bFGF e VEGF na secreção de estrógenos na placenta bovina via modulação da expressão da aromatase P450 in vitro. Conclui-se que estes fatores de crescimento agem como potentes moduladores de enzimas esteroidogênicas e que, sob as condições de cultivo estabelecidas, as células placentárias de bovinos clonados apresentam padrão de resposta distinto quando comparadas com células de bovinos não clonados de mesma idade gestacional. / Vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) are important regulators of placental development and function. Their effects on the steroidogenic enzyme aromatase P450 (P450arom) expression from bovine placenta at different gestational stages (90 - 270 days) were evaluated by immunocytochemistry. Moreover, we compared the effects of these growth factors on P450arom expression between cloned and non cloned bovine placental cells. P450arom was localized exclusively in trophoblast giant cells cytoplasm, and its expression reached lowest levels at day 150 of gestation in comparison to the remaining evaluated gestational stages. VEGF (50 ng/mL) influenced significantly P450arom expression at days 150 and 270, whereas bFGF (10 ng/mL) was effective in stimulating P450arom expression particularly during late gestation (day 270). The two factors combined (bFGF+VEGF) inhibited P450arom expression during early gestation (day 90), but, in contrast, stimulated it at days 150 and 270 of pregnancy (P<0.05). In cloned bovine placental cells, P450arom expression was similar to non-cloned cells in the control and VEGF groups, however, bFGF and both factors together inhibited it significantly (P<0.05). In all groups analyzed, P450arom expression presented rising pattern over the duration of the culture, reaching maximal values at 96 hours of incubation. Thus, the present study demonstrated distinct and stage-specific effects of these growth factors on bovine placenta P450arom expression in vitro. We concluded that these growth factors act as potent steroidogenic enzymes regulators, and, under the established culture conditions, placental cells from cloned bovines presented distinct answer pattern compared to non cloned placental cells at the same gestational stage.
133

Algebry konečného relačního stupně / Finitely Related Algebras

Goldstein, Marek January 2017 (has links)
An algebraic structure is finitely related if its clone is determined by a finite set of finitary relations. In this thesis we examine graph algebras in order to determine which of them have this property. We provide a brief sum- mary of a background theory and we present an overview of known results, in particular, we emphasize the relation between finitely related algebras and Mal'cev conditions. Further we present basic results about the structure of graph algebras. The main part of this thesis is a partial classification of finitely related graph algebras. We provide proofs for various classes of graph algebras, for example for algebras defined by connected bipartite graphs or algebras de- fined by graphs containing certain subgraphs, although several cases are missing to complete the classification. 1
134

An automated multicolour fluorescence in situ hybridization workstation for the identification of clonally related cells

Dubrowski, Piotr 05 1900 (has links)
The methods presented in this study are aimed at the identification of subpopulations (clones) of genetically similar cells within tissue samples through measurement of loci-specific Fluorescence in-situ hybridization (FISH) spot signals for each nucleus and analyzing cell spatial distributions by way of Voronoi tessellation and Delaunay triangulation to robustly define cell neighbourhoods. The motivation for the system is to examine lung cancer patient for subpopulations of Non-Small Cell Lung Cancer (NSCLC) cells with biologically meaningful gene copy-number profiles: patterns of genetic alterations statistically associated with resistance to cis-platinum/vinorelbine doublet chemotherapy treatment. Current technologies for gene-copy number profiling rely on large amount of cellular material, which is not always available and suffers from limited sensitivity to only the most dominant clone in often heterogeneous samples. Thus, through the use of FISH, the detection of gene copy-numbers is possible in unprocessed tissues, allowing identification of specific tumour clones with biologically relevant patterns of genetic aberrations. The tissue-wide characterization of multiplexed loci-specific FISH signals, described herein, is achieved through a fully automated, multicolour fluorescence imaging microscope and object segmentation algorithms to identify cell nuclei and FISH spots within. Related tumour clones are identified through analysis of robustly defined cell neighbourhoods and cell-to-cell connections for regions of cells with homogenous and highly interconnected FISH spot signal characteristics. This study presents experiments which demonstrate the system’s ability to accurately quantify FISH spot signals in various tumour tissues and in up to 5 colours simultaneously or more through multiple rounds of FISH staining. Furthermore, the system’s FISH-based cell classification performance is evaluated at a sensitivity of 84% and specificity 81% and clonal identification algorithm results are determined to be comparable to clone delineation by a human-observer. Additionally, guidelines and procedures to perform anticipated, routine analysis experiments are established. / Science, Faculty of / Physics and Astronomy, Department of / Graduate
135

cDNA SEQUENCES OF THE CAPRINE GAMMA DELTA T CELL HYBRID CO-RECEPTOR AND PATHOGEN RECOGNITION RECEPTOR WC1 MULTIGENE FAMILY

Solangi, Maria 24 March 2017 (has links)
Workshop cluster 1 (WC1) molecules are exclusively expressed on the surface of gamma delta T cells and act as co-receptors and bind pathogens thus also functioning as pattern recognition receptors. The aim was to obtain cDNA evidence to support the recent caprine genome annotation of the WC1 multigene family conducted by a colleague. To get cDNA sequences three strategies were used. Strategy 'I' was used to obtain three clones that corresponded to WC1 SRCR domain d9 through the intracytoplasmic tail sequence. Strategy 'II' was used to obtain 6 clones. A PCR was conducted using SRCR domain b7 through the intracytoplasmic tail sequence. A third strategy obtained full-length WC1 transcripts. The three sequences that extended from SRCR domain d9 to the intracytoplasmic tail matched closely with predicted goat Gene 1 or 14. Another 3 sequences that extended from the SRCR b7 domain through SRCR domain d11 or through the intracytoplasmic tail matched with the predicted Genes 1, 2 and 14, respectively. Two additional full-length cDNA clones CH-MA-03 and 41 were completely sequenced in stages which involved a PCR amplication of the internal domains to complete the sequencing. The a1 domain of CH-MA41 was 100% similar to the annotated and predicted Gene 4 while CH-MA03 also was closest to Gene 4 with a 99% similarity. However, the intracytoplasmic tail sequence of these two cDNA clones was a Type II tail while Gene 4 had a Type I tail. Because of this difference in tails these two cDNA clones had a greater overall similarity with Genes 7 and 15 which had Type II tails. These results suggest that the genome assembly may have errors.
136

Empirische Untersuchung der Eignung von Code-Clones für den Nachweis der Redundanz als Treiber für die Evolution von Programmierkonzepten

Harnisch, Björn Ole 12 February 2018 (has links)
Bei der Entwicklung von Programmen werden durch Entwickler regelmäßig Code-Clones durch das Kopieren von Quellcode erzeugt. In dieser Arbeit wird ein Ansatz zur automatisierten Messung dieses duplizierten Codes mit Hilfe von Clone-Detection-Tools über mehrere Versionen von verschiedenen Software-Produkten gezeigt. Anhand der Historien von Code-Clones werden Einflüsse auf die Redundanzen dieser Software empirisch gemessen. Damit wird eine Grundlage für den Beweis, dass die Entwicklung von Programmiersprachen zu einem dominanten Teil durch Redundanzreduzierung getrieben wird, geschaffen.:Inhaltsverzeichnis Abstract I Inhaltsverzeichnis II 1 Einleitung 1 1.1 Problemstellung 1 1.2 Zielsetzung 1 1.3 Vorgehensweise 3 2 Vorbetrachtung 5 2.1 Programmierkonzepte 5 2.1.1 Definition 5 2.1.2 Programmierkonzepte in Java 5 2.2 Treiber für die Entwicklung von Programmierkonzepten 8 2.2.1 Arten der Treiber von Programmierkonzepten 9 2.2.2 Reduzierung von Redundanz in Software 10 2.2.2.1 Arten von Redundanz in Software 10 2.2.2.2 Code-Clones 11 2.2.2.3 Folgen von Redundanz in Software 13 2.2.3 Ansätze für den Nachweis von Redundanzreduzierung als Treiber 14 2.3 Auswahl Software Repositories für die Analysen 16 2.3.1 Arten von Software Repositories 16 2.3.2 Anforderung an Software Repositories 17 3 Erhebungsprozess für die Analyse von Software auf Clones 20 3.1 Aufbau des Erhebungsprozesses 20 3.1.1 Lösungsansatz 20 3.1.2 Prozessteuerung 21 3.2 Umgang mit Versionierung 22 3.2.1 Allgemein 22 3.2.2 Commit-Filter 24 3.3 Clone-Detection 25 3.3.1 Arten und Vertreter 25 3.3.2 Eigene Verwendung 28 3.3.2.1 Simian 28 3.3.2.2 CCFinderX 29 3.3.3 Laufzeitproblem und Lösungsansätze 31 3.4 Datenaggregation 32 4 Auswertung der Messungen 35 4.1 Vorgehensweise der Auswertung 35 4.2 Betrachtung von Code-Clone-Historien 35 4.3 Vergleich unterschiedlicher Konfigurationen 41 4.3.1 Vergleich unterschiedlicher Clone-Detection-Tools 41 4.3.2 Vergleich unterschiedlicher Commit-Filter 45 4.3.3 Vergleich unterschiedlicher Schwellwerte für die Erkennung 46 4.4 Untersuchung verschiedener Interessenpunkte 48 5 Nachbetrachtung 53 5.1 Fehlerbetrachtung 53 5.2 Erweiterungsmöglichkeiten 55 5.3 Schlussbemerkung 57 Anhang V Vorgehensweise der Literaturrecherchen V Verwendete Computerkonfiguration IX Beispiele für Dateien X Beispiel für Detailausgabe von Simian X Beispiel für Detailausgabe von CCFinderX XI Beispiel für aggregierte Daten XII Abbildungsverzeichnis XIII Tabellenverzeichnis XIV Programmtextverzeichnis XV Abkürzungsverzeichnis XVI Literaturverzeichnis XVII Eidesstattliche Erklärung XXIII
137

Arten der Redundanz im Zusammenhang mit Code-Clones

Willert, Nico 19 November 2018 (has links)
Durch Redundanz im Quellcode kommt es zur Einschränkung wichtiger Faktoren wie der Lesbarkeit oder Wartbarkeit des Codes. Damit einhergehend kann Fehlverhalten im Programmablauf entstehen, wenn Code-Fragmente gezielt dupliziert werden, anstatt sie wiederzuverwenden. Für die frühzeitige Erkennung solcher Probleme ist es daher nötig, die Redundanz in ihren verschiedenen Formen aufzuschlüsseln. Das Ziel dieser Arbeit war es zu untersuchen, wodurch sich diese Formen beziehungsweise Arten der Redundanz unterscheiden, wie diese zusammenhängen und auf welche Weise man Redundanz mit dem Begriff Code-Clone zusammenführen kann. Zu diesem Zweck wurde eine Literaturstudie durchgeführt, um den aktuellen Forschungsstand zu erfassen. Dabei wurden neben der Redundanz auch die Themen Code-Clones und Ähnlichkeit betrachtet. Die Ergebnisse der Literaturstudie wurden anhand der Arten der Redundanz gegliedert und durch Code-Clone-Beispiele verdeutlicht. Die Literaturstudie ergab, dass Redundanz vorwiegend durch Duplikation von Code- Fragmenten entsteht, wodurch sich mithilfe von Code-Clones ein Großteil der Redundanz abbilden lässt. Des Weiteren sind die Arten der Redundanz nicht disjunkt, wodurch sich eine hundertprozentige Untergliederung nicht durchführen lässt.:Gliederung AbbildungsverzeichnisI Quellcode-Listing 1. Einleitung 1.1 Motivation 1.2 Zielstellung 1.3 Aufbau der Arbeit 2. Definitionen 3.Vorgehen 3.1Methodisches Vorgehen 3.2 Planung 3.3 Selektion 3.4 Extraktion 3.5 Ausführung 4. Ergebnisse 4.1 Negative Software Redundanz 4.2 Textuelle Redundanzen 4.3 Funktionelle Redundanz 4.4 Boilerplate-Code 4.5 Entstehungsgrund-basierte Redundanzen 4.5.1 Gezwungene Redundanz 4.5.2 Zufällige Redundanz 4.6 Abgrenzung der Redundanzarten voneinander 5. Fazit 6. Ausblick Quellen
138

Reverse Genetics-based Approaches to Attenuate Porcine Reproductive and Respiratory Syndrome Virus (PRRSV)

Ni, Yanyan 01 November 2013 (has links)
Porcine reproductive and respiratory syndrome virus (PRRSV) is arguably the most economically-important swine pathogen. As the emergences of novel virulent strains of PRRSV continue to occur worldwide, rapid vaccine development is the key for effective control of ongoing PRRSV outbreaks. With the availability of the PRRSV reverse genetics systems, rapid vaccine development against PRRSV through the manipulation of the reverse genetics becomes feasible. To facilitate the vaccine development effort and study of PRRSV genes, we first established a DNA-launched infectious clone of the passage 14 PRRSV strain VR2385, pIR-VR2385-CA, and identified a spontaneous 435-bp deletion in the nsp2 gene. To characterize the biological and pathological significance of this nsp2 deletion, we restored deleted nsp2 sequence back to pIR-VR2385-CA and constructed another clone pIR-VR2385-R. VR2385-CA and VR2385-R were successfully rescued in vitro. The results from this study indicates that the spontaneous nsp2 deletion plays a role for enhanced PRRSV replication in vitro but has no significant effect on the pathogenicity of the virus. With the availability of the DNA-launched infectious clone of PRRSV, we successfully applied the molecular breeding approach to rapidly attenuate PRRSV. The GP5 envelope genes of 7 genetically divergent PRRSV strains and the GP5-M genes of 6 different PRRSV strains were molecularly bred. DS722 with shuffled GP5 genes and DS5M3 with shuffled GP5-M genes, were successfully rescued in vitro and shown to be attenuated both in vitro and in vivo. Furthermore, DS722, but not DS5M3, still elicit similar protection against PRRSV challenge as its parental virus. This study reveals a unique approach through DNA shuffling of viral envelope genes to attenuate a positive-strand RNA virus. We subsequently utilized the novel synthetic attenuated virus engineering (SAVE) approach to attenuate PRRSV. The GP5 and nsp9 genes of PRRSV were codon-pair deoptimized with the aid of a computer algorithm. SAVE5 and SAVE9 with deoptimized GP5 gene and SAVE9 with deoptimized nsp9 gene, were successfully rescued and shown to be attenuated in vitro. An in vivo pathogenicity study indicated the attenuation of SAVE5 virus in vivo. The results have important implications for rapid vaccine development against PRRSV and other important viruses. / Ph. D.
139

Code duplication and reuse in Jupyter notebooks

Koenzen, Andreas Peter 21 September 2020 (has links)
Reusing code can expedite software creation, analysis and exploration of data. Expediency can be particularly valuable for users of computational notebooks, where duplication allows them to quickly test hypotheses and iterate over data, without creating code from scratch. In this thesis, I’ll explore the topic of code duplication and the behaviour of code reuse for Jupyter notebooks; quantifying and describing snippets of code and explore potential barriers for reuse. As part of this thesis I conducted two studies into Jupyter notebooks use. In my first study, I mined GitHub repositories, quantifying and describing code duplicates contained within repositories that contained at least one Jupyter notebook. For my second study, I conducted an observational user study using a contextual inquiry, where my participants solved specific tasks using notebooks, while I observed and took notes. The work in this thesis can be categorized as exploratory, since both my studies were aimed at generating hypotheses for which further studies can build upon. My contributions with this thesis is two-fold: a thorough description of code duplicates contained within GitHub repositories and an exploration of the behaviour behind code reuse in Jupyter notebooks. It is my desire that others can build upon this work to provide new tools, addressing some of the issues outlined in this thesis. / Graduate
140

General and Specific Combining Ability of five Alfalfa Clones Including Reciprocal Effects for Seedling Vigor and Seed Yield

Bingham, Edwin Theodore 01 May 1961 (has links)
The use of F1 hybrids for commercial production of such cross-pollinated crops as corn, sorghum, sugar beets, onions, and pearl millet suggests the feasibility of using this technique for alfalfa. Production of F1 hybrids of commercial value is dependent on the use of breeding material expressing good combining ability. In order to obtain precise estimates of combining ability for quantitative characters in alfalfa, it is necessary to produce all possible single crosses among a number of parents. The single cross seed required is difficult to obtain due to the vegetative reproduction and isolation required; and, subsequently, limited testing of this type has been conducted in alfalfa. Testing breeding material for combining ability based on seed production has been more limited than testing based on forage yield or various other measurements. In this experiment a diallel crossing system was used to test the general and specific combining ability of five alfalfa clones previously selected for good general combining ability. The report is based on first-year data of a three-year study, and the results are subject to errors which may occur due to variability inherent in the year of establishment. This is especially true for conclusions based on seed production. However, first-year data should be valid for such characteristics as flower color and seedling height. The analysis of seed production and seedling height is designed to measure the relative amount of general and specific combining ability of the cones involved. Reciprocals of the single crosses were evaluated for flower color, seedling height, and seed yield to check if reciprocal cross progeny give equal performance.

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