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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Molecular characterization of digestive proteases of the yellow mealworm, Tenebrio molitor L.

Prabhakar, Sheila January 1900 (has links)
Doctor of Philosophy / Department of Entomology / C. M. Smith / Brenda Oppert / Coleopteran insects compensate for dietary protease inhibitors by a number of mechanisms. To study this compensation response at the molecular level, the digestive proteases of Tenebrio molitor were studied. Biochemical studies of the pH optima and inhibitor sensitivity of proteases indicated the cysteine proteases were mostly in the anterior and serine proteases were in the posterior midgut of T. molitor larvae. Expressed Sequence Tags (ESTs) from T. molitor larval midgut cDNA libraries contained sequences encoding putative digestive proteases. Of a total of 1,528 cDNA sequences, 92 cDNAs encoded proteases, and 50 full-length cDNAs were grouped into serine, cysteine and metallo protease classes. Sequences tmt1a, tmt1b and tmt1c were identified as genes encoding isoforms of T. molitor trypsin, and tmc1a encoded T. molitor chymotrypsin. The general distribution cysteine protease transcripts in the anterior and serine protease transcripts in the posterior midgut, of T. molitor larvae, was in agreement with the biochemically-characterized compartmentalization of proteases. Expression analyses of selected transcripts demonstrated varied expression patterns across five developmental stages of T. molitor, with maximal expression of most protease transcripts in first instar larvae. Dietary serine and cysteine protease inhibitors fed in combination to early-instar T. molitor larvae caused a significant delay in larval growth in 21-day-old larvae. Real-time quantitative PCR analysis of RNA isolated from larvae fed different protease inhibitor treatments indicated that dietary inhibitors affected the expression of serine and cysteine proteases. Larvae fed soybean trypsin inhibitor, a serine protease inhibitor, compensated by the hyperproduction of proteases from the same class, as well as the upregulation of cysteine proteases. A cysteine protease inhibitor, E-64, caused a reduction in the hyperproduction of all proteases, and, in combination with the soybean trypsin inhibitor, lowered the compensation response of T. molitor larvae to negligible levels. These data suggest that T. molitor larvae are more sensitive to the effects of cysteine protease inhibitors, perhaps because these proteases are the first line of defense for larvae against plant protease inhibitor. The bioassay and molecular studies suggested that combinations of inhibitors that target both serine and cysteine proteases are needed to effectively control larval infestations of T. molitor.
82

Evaluation of Some Statistical Methods for the Identification of Differentially Expressed Genes

Haddon, Andrew L 24 March 2015 (has links)
Microarray platforms have been around for many years and while there is a rise of new technologies in laboratories, microarrays are still prevalent. When it comes to the analysis of microarray data to identify differentially expressed (DE) genes, many methods have been proposed and modified for improvement. However, the most popular methods such as Significance Analysis of Microarrays (SAM), samroc, fold change, and rank product are far from perfect. When it comes down to choosing which method is most powerful, it comes down to the characteristics of the sample and distribution of the gene expressions. The most practiced method is usually SAM or samroc but when the data tends to be skewed, the power of these methods decrease. With the concept that the median becomes a better measure of central tendency than the mean when the data is skewed, the tests statistics of the SAM and fold change methods are modified in this thesis. This study shows that the median modified fold change method improves the power for many cases when identifying DE genes if the data follows a lognormal distribution.
83

Dříve vyslovená přání a jejich realizace v praxi / Advance directives and its realisation in current practice

Šnajdarová, Lenka January 2018 (has links)
The aim of this diploma work is to search the answer to question: What are the causes for little use of advanced directives in real life from expert's point of view? Text is separated into theoretical part, methodological and analytical. In theoretical part, the autor is conceptualising basic terms from main research question and is leading the revers into the context. Methodological part is revealing the background of the research, which was carried out by qualitative research strategy through half-structured interviews with chosen experts in problems with advanced directives. In analytical part are presented results of research, which the autor is comparing to theoretical roots. Particiapnts of the research are seeing the causes of little use in advanced directives in little information about its existence, in legal format and its rising concerns from possible legal punishment and last but not least it can be caused by ethical and personal background. Keywords Advanced directives, illness, autonomy, causes, practise.
84

Dříve vyslovená přání a jejich realizace v praxi / Advance directives and its realisation in current practice

Šnajdarová, Lenka January 2019 (has links)
The aim of this diploma work is to search the answer to question: What are the causes for little use of advanced directives in real life from expert's point of view? Text is separated into theoretical part, methodological and analytical. In theoretical part, the autor is conceptualising basic terms from main research question and is leading the revers into the context. Methodological part is revealing the background of the research, which was carried out by qualitative research strategy through half-structured interviews with chosen experts in problems with advanced directives. In analytical part are presented results of research, which the autor is comparing to theoretical roots. Particiapnts of the research are seeing the causes of little use in advanced directives in little information about its existence, in legal format and its rising concerns from possible legal punishment and last but not least it can be caused by ethical and personal background. Keywords Advanced directives, illness, autonomy, causes, practise.
85

Comparative Deep Transcriptional Profiling of Four Developing Oilseeds

Troncoso-Ponce, Manuel A., Kilaru, Aruna, Cao, Xia, Durrett, Timothy P., Fan, Jilian, Jensen, Jacob K., Thrower, Nick A., Pauly, Markus, Wilkerson, Curtis, Ohlrogge, John B. 01 December 2011 (has links)
Transcriptome analysis based on deep expressed sequence tag (EST) sequencing allows quantitative comparisons of gene expression across multiple species. Using pyrosequencing, we generated over 7 million ESTs from four stages of developing seeds of Ricinus communis, Brassica napus, Euonymus alatus and Tropaeolum majus, which differ in their storage tissue for oil, their ability to photosynthesize and in the structure and content of their triacylglycerols (TAG). The larger number of ESTs in these 16 datasets provided reliable estimates of the expression of acyltransferases and other enzymes expressed at low levels. Analysis of EST levels from these oilseeds revealed both conserved and distinct species-specific expression patterns for genes involved in the synthesis of glycerolipids and their precursors. Independent of the species and tissue type, ESTs for core fatty acid synthesis enzymes maintained a conserved stoichiometry and a strong correlation in temporal profiles throughout seed development. However, ESTs associated with non-plastid enzymes of oil biosynthesis displayed dissimilar temporal patterns indicative of different regulation. The EST levels for several genes potentially involved in accumulation of unusual TAG structures were distinct. Comparison of expression of members from multi-gene families allowed the identification of specific isoforms with conserved function in oil biosynthesis. In all four oilseeds, ESTs for Rubisco were present, suggesting its possible role in carbon metabolism, irrespective of light availability. Together, these data provide a resource for use in comparative and functional genomics of diverse oilseeds. Expression data for more than 350 genes encoding enzymes and proteins involved in lipid metabolism are available at the 'ARALIP' website ().
86

The Relations Between Maternal Expressed Emotion and Children's Perceived Self-Competence, Behavior and Intelligence in African-American Families

Kwon, Julie, Delaney-Black, Virginia, Covington, Chandice, Abell, Steven C., Nordstrom-Bailey, Beth, Sokol, Robert J., Ager, Joel 01 December 2006 (has links)
This study examined the relationship between maternal expressed emotion (EE) and children's perceived self-competence, behavior and intelligence in a community sample of 190 urban, African American children ages 6-7. Maternal EE was measured by the Five Minute Speech Sample. Self reports and standardized measures were used to examine other mother and child variables. Compared with Low EE, High EE was associated with children's decreased cognitive self-concept, increased anxiety, and greater levels of hyperactivity. EE was unrelated to children's intelligence. The study suggests that for African American children at early school age, maternal EE predicts child anxiety, perceived cognitive competence, and hyperactive behavior. Further investigation appears warranted to evaluate the relationship, over time, between EE and child outcomes.
87

Identification and Analysis of Safener-Inducible Expressed Sequence Tags in Populus Using a cDNA Microarray

Rishi, A. S., Munir, Shirin, Kapur, Vivek, Nelson, Neil D., Goyal, Arun 01 December 2004 (has links)
Safeners are the chemicals used to protect plants from detrimental effects of herbicides, but their mode of action at the molecular level is not well understood. As an initial step towards understanding the molecular mechanism of safener action in trees, homologous genes in hybrid poplar (Populus nigra x Populus maximowiczii) that were induced by a safener were identified. We here describe the identification of differentially expressed genes in Populus that are induced by Concep-III, a herbicide safener. Expressed sequence tags (ESTs) enriched for transcriptionally induced genes were isolated by suppressive subtractive hybridization (SSH). The SSH library cDNA inserts were used to construct a cDNA microarray for high-throughput validation of the up-regulated expression of safener-induced genes. Single-pass and partial sequences of 1,344 safener-induced ESTs were assembled into 418 single-tons and 328 clusters, but the putative functions of almost 53% of the ESTs are not known. Genes encoding proteins involved in all three different phases of safener action, viz., oxidation, conjugation, and sequestration, were found in the SSH library. Almost 75% of genes that showed greater than 2-fold expression upon safener treatment were redundant in the SSH library. The expression pattern for selected genes was validated by reverse transcription-polymerase chain reaction. A few safener-induced genes that were not previously reported to be induced by safeners, but which may have a role in herbicide metabolism, were identified. The newly identified genes could have potential for application in genetic engineering of plants for herbicide detoxification and tolerance.
88

Comparative transcriptome profiling of human and pig intestinal epithelial cells after Deltacoronavirus infection

Cruz Pulido, Diana Patricia 30 September 2020 (has links)
No description available.
89

Altering Histone Dynamics <i>in vitro</i> and <i>in vivo</i>

Howard, Cecil J., II January 2018 (has links)
No description available.
90

Identifying Differentially Expressed Human Lung MicroRNAs and Their Molecular Functions

Limbu, Sarita 23 December 2009 (has links)
No description available.

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