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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.
151

Generation of a reporter for mitochondrial gene expression studies

Temperley, Richard James January 2001 (has links)
No description available.
152

Evaluation of Timing of Vancomycin Surgical Site Infection Prophylaxis with Scheduled Antibiotic

Wong, Edric, Clonts, Jason January 2012 (has links)
Class of 2012 Abstract / Specific Aims: The primary purpose of this study was to evaluate the time of vancomycin pre-operative surgical site infection prophylaxis administration relative to other scheduled antibiotic therapy at a tertiary care, academic medical center. The secondary purpose was to characterize the incidence of adverse events post-surgery that were associated with vancomycin therapy in patients who received both pre- operative scheduled vancomycin therapy and vancomycin for surgical site infection prophylaxis Methods: This descriptive study was a retrospective medical chart review of all patients over the age of 28 days who received vancomycin for surgical site infection prophylaxis between February 2011 and May 2011 at a tertiary care, academic medical center. This study was approved be the Institutional Review Board. The subject population included patients admitted to the hospital for at least 72 hours who received at least 48 hours of scheduled vancomycin (IV), daptomycin or linezolid therapy before index surgery and subsequently received surgical site infection prophylaxis with vancomycin. Main Results: Of the 20 subjects who meet the study inclusion criteria, 18 (90%) subjects received scheduled vancomycin doses within 48 hours prior to surgery, 5 (25%) subjects within 4 hours, and 4 (20%) subjects within 2 hours. No surgical site infections were reported. Conclusions: This was a pilot study to evaluate the timing of vancomycin surgical site infection prophylaxis doses with scheduled vancomycin, linezolid, and daptomycin. No adverse effects associated with surgical site infection prophylaxis were reported but the sample size is small and likely inadequate to detect this potential issue.
153

Site Formation Processes and Bone Preservation Along the Trinity River Basin, North Central Texas

Colvin, Jessica 08 1900 (has links)
This thesis presents the results of geoarchaeological investigations of several archaeological sites along the Elm Fork of the Trinity River in north central Texas. Archaeological data recorded from mitigation excavations in Denton and Cooke counties were analyzed to understand the geologic impacts on faunal preservation resulting from site formation processes. The faunal assemblages are highly fragmented, even in settings known for good preservation. A combined approach using geoarchaeological and taphonomic techniques was implemented to examine how fragmentation, evidence of soil weathering, and differential preservation were impacted by differing geologic conditions throughout the river basin. Intrasite and intersite results of the sites show that a great deal of variability of faunal preservation is present at difference scales of analysis.
154

Exploratory making: site inspired making as a tool for site analysis and design

Moore, Wesley January 1900 (has links)
Master of Landscape Architecture / Landscape Architecture/Regional and Community Planning / Jon D. Hunt / Design tools (the method of making a designer uses to conceptualize or communicate the assembly of an object) are not simply secondary instruments to communicate designs through, but are the primary media through which designers contemplate and process design problems. Designers should utilize tools, whether digital or analog, with an awareness of each tool’s limitations and advantages and the possibilities they provide to each step of the design process. The intent of this report is to study how site inspired making methods can be used to observe and reveal information about a site, and thus contribute to the site analysis phase of design. Site inspired making methods are developed in this report through an exploratory research process. Exploratory research is a qualitative method used to provide flexibility in developing knowledge about a topic. An exploratory process was chosen to allow my focuses to shift as I make and reflect so my findings arise as I conduct the studies, not just from an initial hypothesis. Through an exploratory research process of making and reflecting this report answers the question: How do various methods of making develop and document my understanding of the site? Exploratory methods of drawing and sculpting are used to observe and reveal site information, and develop site-inspired artistic works. The site is a small, wooded lot and cove of Tuttle Creek Lake located northwest of Manhattan, Kansas. The research process is divided into an investigation phase in which I explored initial drawing and sculpting methods and an application phase in which I created a sculpture and series of drawings inspired by the site. I documented site conditions through observational drawing; revealed patterns and textures by drawing with and on site materials; developed parametric studies of balancing sculptures; discovered crystallization patterns by splattering ink on a frozen lake; designed a balancing sculpture inspired by the motion of ice sheets and driftwood on water; and created frost drawings by applying ink to soaked and frozen watercolor paper. Each method revealed different site qualities and informed my understanding of the site.
155

The accuracy of the wind stress over ocean of the Rossby Centre Atmospheric model (RCA)

Ohlsson, Alexandra January 2006 (has links)
The aim of this study is to investigate how well the wind stress is described in the regional climate model RCA (Rossby Centre Atmospheric model). The model data is compared with measurements taken at Östergarnsholm, an island located east of Gotland in the Baltic Sea. The investigation covers the period October 1997 to September 2000. Compared with the measurements RCA underestimates the wind speed over ocean in most cases. When the wind speed is studied in monthly mean it was found that the wind speed is consistently underestimated in the model, especially during summer and early winter. The wind stress is also underestimated during the year except during late winter and in October when it is overestimated. When wind speed from the model and measurements were studied it was found that lower wind speed is overestimated in the model. This contributes to overestimation of the wind stress for lower wind speeds. For higher wind speeds both wind speed and wind stress is underestimated in RCA. If the model would have a correct wind speed the wind stress would be overestimated with 20-30 % for all wind speeds compared to the measured. This is probably due to miscalculations of wind stress in the model. RCA fail to capture the stability in a satisfactory way. The model describes most of the times a different stratification than the measurements do. Separate studies over modeled and measured wind speed and wind stress was made. RCA is found to represent stable condition well. During unstable stratification modeled wind speed and wind stress are underestimated. Investigation of the measured wave age shows that the model underestimates both wind speed and wind stress for growing sea and mature sea. For the situations when the measured wave age was defined as swell the model overestimated wind speed and wind stress.2 / Den här studien tar upp hur väl friktionen över havsytan beskrivs i den regionala klimatmodellen RCA (Rossby Centre Atmospheric model). Modelldata jämförs med mätningar gjorda på Östergarnsholm, en ö belägen öster om Gotland i Östersjön. Studien spänner över tidsperioden oktober 1997 till september 2000. RCA underskattar i många fall vindhastigheten på 10 m över havsytan jämfört med mätningarna. Då månadsmedelvärden studeras visar det sig att modellen genomgående underskattar vindhastigheten, särskilt på sommaren och på vintern. Friktionen överskattas under sen vinter och för oktober månad. För alla andra månader underskattas friktionen. Studier över vindhastigheterna visar på att de lägre vindhastigheterna överskattas i modellen. Detta bidrar till överskattning av friktionen för de lägre vindhastigheterna. För högre vindhastigheter underskattar RCA vindhastigheterna och därmed även friktionen. Om modellen skulle ge en korrekt vindhastighet skulle resultatet istället visa på en överskattning av friktionen med 20-30 % för alla vindhastigheter. Detta beror troligen på felaktigheter i beräkningen av friktionen i modellen. Stabiliteten visar sig vara dåligt beskriven i RCA. I de flesta fall är skiktningen i modellen och mätningarna helt olika. Jämförelser mellan separata studier mellan modelldata och mätningar visar att vindhastigheten och friktionen beskrivs bra under stabila förhållanden, men i samband med instabil skiktning underskattas vindhastigheten och friktionen i modellen. Studier över den uppmätta vågåldern visar att modellen underskattar både vindhastigheten och friktionen för växande och fullvuxen sjö. Då det råder dyning överskattar modellen både vindhastigheten och friktionen.
156

Scaffolding Catalysis: Towards Regioselective Hydroformylation of Alkenes and Site-Selective Functionalization of Polyhydroxylated Molecules

Sun, Xixi January 2013 (has links)
Thesis advisor: Kian L. Tan / Chapter 1. We reported the first synthesis of all-carbon quaternary centers via hydroformylations using a catalytic directing group. With the ability of reversibly and covalently binding to a substrate, and coordinating to a metal center, scaffolding catalyst 1.1 is able to direct the branch-selective hydroformylation of 1,1-disubstituted olefins under mild temperature. Chapter 2. We have designed and synthesized a chiral organocatalyst 2.11. This catalyst is able to covalently bind to one hydroxyl, and utilize the induced intramolecularity to stereoselectively functionalize the other hydroxyl within a cis-1,2-diol via electrophile transfer. Catalyst 2.11 was used in the desymmetrization of meso-1,2-diols under mild conditions (4 C to room temperature), leading to high yields and selectivities for a broad substrate scope. Chapter 3. Catalyst 3.1 and 3.6 were demonstrated to selectively bind to primary hydroxyls over secondary hydroxyls. By combining the binding selectivity with asymmetric catalysis, these scaffolding catalysts were shown to promote the selective silylation of secondary hydroxyls within terminal (S)-1,2-diols. The reversal of substrate bias was further applied to a regiodivergent kinetic resolution of racemic terminal 1,2-diols, producing secondary protected products in synthetically practical levels of enantioselectivity (>95:5 er) and yields (≥40%). Time course studies of this reaction further revealed the optimal condition to form the primary silylated product in high s-factor. Chapter 4. Based on the previous understanding of catalyst 4.5 and 4.6, the exclusive catalyst recognition of cis-1,2-diols within polyhydroxylated molecules was further discovered. This unique functional group display recognition was further allied with the catalyst's ability to stereoselectively differentiate hydroxyls within cis-1,2-diols, enabling the site-selective protection, functionalization, and activation of the inherently less reactive axial hydroxyl groups within carbohydrates. This methodology also enables the selective functionalization of multiple complex molecules, including digoxin, mupirocin, and ribonucleosides, demonstrating the potential power of scaffolding catalysis in the rapid access to valuable synthetic derivatives of polyhydroxylated compounds. / Thesis (PhD) — Boston College, 2013. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Chemistry.
157

Coupling of dextran T40 to recombinant trichosanthin created by site-directed mutagenesis: the effect on bioactivities, nephrotoxicity and immunogenicity of trichosanthin.

January 1995 (has links)
by Chan Wah Lun. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1995. / Includes bibliographical references (leaves 252-260). / Acknowledgments --- p.i / Abstract --- p.ii / Contents --- p.vi / Naming of TCS mutants and modified TCS protein --- p.x / Abbreviations --- p.xi / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Physical and chemical properties of Trichosanthin --- p.1 / Chapter 1.2 --- Biological activities of Trichosanthin --- p.3 / Chapter 1.3 --- Renal tubular reabsorption and nephrotoxicity of Trichosanthin --- p.10 / Chapter 1.4 --- Objective and strategies of study --- p.11 / Chapter Chapter 2 --- Materials and methods --- p.19 / Chapter 2.1 --- General Techniques --- p.19 / Chapter 2.2 --- Site directed mutagenesis of Trichosanthin --- p.21 / Chapter 2.3 --- DNA sequencing --- p.37 / Chapter 2.4 --- Overexpression of modified Trichosanthin in E. coli --- p.42 / Chapter 2.5 --- Purification of modified Trichosanthin --- p.43 / Chapter 2.6 --- Breaking of Disulphide bridge between modified TCS --- p.44 / Chapter 2.7 --- Coupling of DX T40 to modified Trichosanthin --- p.44 / Chapter 2.8 --- Biological activities of modified Trichosanthin and Dextran-modified trichosantin conjugates --- p.46 / Chapter 2.9 --- Immunogenicity of modified Trichosanthin and Dextran-trichosanthin conjugates --- p.50 / Chapter 2.10 --- Nephrotoxicity of Trichosanthin and Dextran-trichosanthin conjugates --- p.53 / Chapter Chapter 3 --- Construction of TCS mutants --- p.61 / Chapter 3.1 --- Introduction --- p.61 / Chapter 3.2 --- Method --- p.61 / Chapter 3.3 --- Results --- p.62 / Chapter 3.3.1 --- Construction of K173C mutant --- p.62 / Chapter 3.3.2 --- Construction of R29C mutant --- p.64 / Chapter 3.3.3 --- Construction of K173C R29C double mutant --- p.65 / Chapter 3.4 --- Discussion --- p.66 / Chapter Chapter 4 --- "Expression,Purification and Ribosome- inactivating activities of Modified Trichosanthin proteins" --- p.87 / Chapter 4.1 --- Introduction --- p.87 / Chapter 4.2 --- Method --- p.87 / Chapter 4.3 --- Results --- p.88 / Chapter 4.3.1 --- "Expression, purification and ribosome-inactivating activity of K173C" --- p.88 / Chapter 4.3.2 --- "Expression ,purification and ribosome-inactivating activity of R29C" --- p.89 / Chapter 4.3.3 --- "Expression, purification and ribosome-inactivating activity of K173C R29C" --- p.90 / Chapter 4.4 --- Discussion --- p.91 / Chapter Chapter 5 --- Coupling of Dextran T40 to modified Trichosanthin --- p.108 / Chapter 5.1 --- Introduction --- p.108 / Chapter 5.2 --- Method --- p.109 / Chapter 5.3 --- Results --- p.109 / Chapter 5.3.1 --- Coupling of R29C --- p.109 / Chapter 5.3.2 --- Coupling of K173C --- p.111 / Chapter 5.3.3 --- Coupling of R29CK173C --- p.111 / Chapter 5.4 --- Discussion --- p.111 / Chapter Chapter 6 --- Biological Activities of modified Trichosanthin and Dextran-modified trichosanthin conjugates --- p.128 / Chapter 6.1 --- Introduction --- p.128 / Chapter 6.2 --- Method --- p.128 / Chapter 6.3 --- Results --- p.130 / Chapter 6.3.1 --- In vivo Biological activity- Mid-term abortifacient activity --- p.130 / Chapter 6.3.2 --- In vitro biological activities / Chapter 6.3.2a --- Ribosome-inactivating activity --- p.131 / Chapter 6.3.2b --- Anti-tumour activity --- p.132 / Chapter 6.4 --- Discussion --- p.133 / Chapter Chapter 7 --- Immunogenicity of Dextran-modified trichosanthin conjugates --- p.156 / Chapter 7.1 --- Introduction --- p.156 / Chapter 7.2 --- Method --- p.157 / Chapter 7.3 --- Results / Chapter 7.3.1 --- Immunogenicity without denaturation of protein --- p.158 / Chapter 7.3.2 --- Immunogenicity with denaturation of protein --- p.161 / Chapter 7.4 --- Discussion --- p.162 / Chapter Chapter 8 --- Nephrotoxicity of Trichosanthin and Dextran-Trichosanthin conjugates --- p.199 / Chapter 8.1 --- Introduction --- p.200 / Chapter 8.2 --- Method --- p.202 / Chapter 8.3 --- Results --- p.202 / Chapter 8.3.1 --- Functional study on nephrotoxicity of Trichosanthin --- p.202 / Chapter 8.3.2 --- Morphological study on the nephrotoxicity of Trichosanthin --- p.203 / Chapter 8.3.3 --- The effect of coupling of Dextran T40 on the nephrotoxicity of Trichosanthin --- p.206 / Chapter 8.4 --- Discussion --- p.207 / Chapter Chapter 9 --- General Discussion --- p.244 / References --- p.252
158

The use of site-directed integration to study genomic and transcriptional stability of recombinant promoters in CHO cells

Pereira, Mário January 2016 (has links)
Transcriptional regulation is a determinant of stability of recombinant protein production in CHO cells. Fundamental studies of recombinant gene transcription in relation to chromatin environment and promoter regulation are important for CHO cell line development and selection. This study has developed a methodology based on a cell/vector system to study recombinant transcription and expression stability of different promoters and/or proteins in the similar genomic environment. The CHO-FRT mini-pools developed in this project were mini-pools of CHO-S cell lines containing Flp Recombination Target (FRT) sites with ß-galactosidase gene, under the influence of a SV40 promoter. Continuous culture of these mini-pools for 8 weeks using a robotic system demonstrated that 20% of the mini-pools studied revealed an unstable profile (with 30% loss of protein expression). Two of these mini-pools with different characteristics, CHO-FRT 1 (low producer/unstable) and CHO-FRT 108 (high producer/stable), were selected to be used on the study of influence of SV40 and CMV promoters in long-term recombinant expression. Genes encoding fluorescent proteins were integrated in a site-directed manner under the influence of SV40 or CMV promoters. A sub-clonal population of the top 10% yellow fluorescent protein (YFP) expressing cells of each mini-pool/promoter combination was selected by cell sorting and cultured for 4 weeks. During this period protein expression was monitored by flow cytometry and compared between both promoters. The results revealed that both SV40 and CMV promoters had an unstable expression with different degrees of instability and long-term expressing behaviours. For CMV, instability was considerably high displaying a long-term logarithmic loss of 50-80% of productivity while for SV40 the loss of productivity observed was only 40-45% with a linear behaviour during long-term culture. The vector system generated contained an MS2-RNA tag sequence cloned 3'- of the recombinant gene to track the recombinant mRNA by using the MS2/MCP-GFP system. This study showed the development of a protocol to measure the transcriptional output of recombinant promoters in CHO cells. The results showed background signal in CHO cells that requires further optimisation studies to allow the direct live cell image quantification of the transcriptional activity of recombinant promoters. Although not yet optimised, the successful combination of site-directed integration with recombinant mRNA tagging method has the potential to become a valuable tool to study the mechanisms of transcriptional activity and stability of transcription driven by different promoters in CHO cells.
159

Building reliable web services: methodology, composition, modeling and experiment. / 修造可靠的網服務: 方法, 構成, 塑造和實驗 / CUHK electronic theses & dissertations collection / Xiu zao ke kao de wang fu wu: fang fa, gou cheng, su zao he shi yan

January 2008 (has links)
Finally, we perform a series of experiments employing several replication schemes and compare them with a non-redundant single service. Through the experiments, we evaluate both the reliability of the Web service paradigm and the correctness of the Web service composition algorithm. / In the paradigm, N-version programming technique is applied to increase the diversity of the system. As different versions of Web services or even different versions of their components are abundantly available in the Internet, the combination of different versions of the Web service or their components is thus becoming critical for enabling different versions in a server application using the N-version approach. We propose a dynamic Web service composition algorithm and evaluate with Petri-Net for verification purposes. / Moreover, we model the Web services with Markov chains and Petri-Nets to demonstrate the performance and reliability of the constructed Web services. Also, we develop the mathematical models to analyze the reliability of the Web services. / One of the latest achievements of the Internet usage is the availability of Web services technology and its dependability is becoming one of the most critical goals in Web related research. In this thesis, we propose a design paradigm for reliable Web services and a Web service composition algorithm. We describe the methods of dependability enhancement by redundancy in space and redundancy in time, using Round-robin scheduling technique, N-version programming and recovery block. The Web services are coordinated by a replication manager. It provides a Round-robin algorithm for scheduling the workload of the Web services and keeps updating the availability of each Web service. The replication algorithm and the detailed system configuration are described. / Chan, Pik Wah. / "March 2008." / Adviser: Micheal R. Lyn. / Source: Dissertation Abstracts International, Volume: 70-03, Section: A, page: 0722. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (p. 114-124). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.
160

Comunidades mediadas pela Internet : uma pesquisa multimétodos para estruturação de base conceitual e projeto de web sites

Bellini, Carlo Gabriel Porto January 2001 (has links)
O objeto de estudo da presente pesquisa são as comunidades mediadas pela Internet (CMIs). Uma CMI consiste de um conjunto de pessoas que compartilham interesses e que, durante algum tempo, utilizam recursos em comum na Internet (por exemplo, um web site – objeto preferencial deste trabalho) para trocarem informações umas com as outras relativamente aos interesses compartilhados. A pesquisa realizada é exploratória e qualitativa, tendo feito uso de estudos de caso, pesquisa-ação e entrevistas em profundidade para estruturar uma base conceitual para as CMIs e reunir elementos relevantes a serem considerados quando da construção de web sites para as mesmas. Realizou-se estudo de caso de 5 (cinco) web sites de CMIs, a fim de serem identificadas as principais tecnologias e métodos em uso atualmente para a estruturação de web sites para CMIs. Na pesquisa-ação, 7 (sete) grupos de pessoas foram identificados e, para cada um, construiu-se 1 (um) web site, de modo que se ofereceu um espaço na Internet para a interação dos seus integrantes. A observação da interação das pessoas através dos web sites permitiu concluir-se que, dos sete grupos iniciais, apenas 1 (um) poderia ser caracterizado como CMI, conforme critérios de Jones (1997): associação sustentável, variedade de comunicadores, espaço virtual para a comunicação em grupo, e interatividade. Para as entrevistas em profundidade, elaborou-se um questionário com base no referencial teórico, nos estudos de caso e na pesquisa-ação, sendo aplicado a 17 (dezessete) pessoas (da única CMI e de dois dos sete grupos). O objetivo das entrevistas foi levantarem-se percepções sobre os web sites utilizados pelos grupos, percepções essas que, sob análise de conteúdo, ajudaram na formação de um conjunto de 12 (doze) recomendações para a construção de web sites para CMIs. As recomendações são de natureza diversa, mas deixam clara a necessidade de haver um entendimento profundo do contexto de uma CMI previamente ao projeto do seu web site.

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