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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.
1

Mold susceptibility of rapidly renewable materials used in wall construction

Cooper, Aaron McGill 15 May 2009 (has links)
Since 1998, the United States Green Building Council, via the Leadership in Energy and Environmental Design (LEED) standards, has established the premiere set of guidelines for construction ethics from the standpoint of eco-friendliness and occupant safety and health in the U.S. and around the world. These guidelines are skyrocketing in use due in part to two reasons: · increased awareness of a need for reducing, reusing, and recycling in order to save resources and natural areas for future generations; and, · increased amount of time spent indoors in work places and homes. The LEED guidelines encourage sustainable and responsible use of land, water, energy, and materials, and promote a safe and healthy environment through use of innovative designs and technology. As part of the responsible use of materials, the LEED guidelines encourage the use of rapidly renewable materials such as cotton, straw, wool, and cork as insulation products. Although these products can be produced naturally and quickly from nature, they are also cellulose or carbohydrate based products. Cellulose and carbohydrate based materials are typically optimal food sources for mold in the presence of moisture, ironically destroying facilities and creating poor living and work environments. Samples of wool, cork, straw, and cotton--rapidly renewable materials used as exterior wall insulation products--were exposed to different moisture amounts in an encapsulated environment, representing the environment within a wall cavity when exposed to water from pipes, leaks, condensation and absorption, or from initial construction. The samples were monitored over time for mold growth. The data logged from the samples were analyzed to determine the degree of mold susceptibility of each material. In addition, samples with increased amounts of moisture were examined to determine increased promotion of mold growth. The results from this study showed that all of the above mentioned materials were highly susceptible to mold growth and that the moisture amount did not increase the rate of mold growth. Based on the data collected from this study, recommendations were made to review the current use of rapidly renewable and other cellulose and carbohydrate based materials in wall construction.
2

Strain-specific profiling of Amyloid-β in Alzheimer´s disease: functional and clinical signature

Noor, Aneeqa 27 May 2021 (has links)
No description available.
3

Surveying Underwater Shipwrecks with Probabilistic Roadmaps

Lewis, Amy Jeannette 01 June 2019 (has links)
Almost two thirds of the Earth's surface is covered in ocean, and yet, only about 5% of it is mapped. There are an unknown amount of sunken ships, planes, and other artifacts hidden below the sea. Extensive search via boat and a sonar tow fish following a standard lawnmower pattern is used to identify sites of interest. Then, if a site has been determined to potentially be historically significant, the most common next step is a survey by either a human dive team or remotely operated vehicle. These are time consuming, error prone, and potentially dangerous options, but autonomous underwater vehicles (AUVs) are a possible solution. This thesis introduces a system for automatically generating paths for AUVs to survey and map shipwrecks. Most AUVs include software to set a lawnmower path for a given region of ocean, and individualized paths can be set via specifying GPS encoded nodes for the AUV to pass through. This thesis presents an algorithm for generating an individualized path that permits the AUV, equipped with a camera to "see" all sides of a region of interest (i.e. a shipwreck). This allows the region of interest to be completely documented. Photogrammetry can then be used to reconstruct a three-dimensional model, but a path is needed to do so. Paths are generated by a probabilistic roadmap algorithm that uses a rapidly-exploring random tree to quickly cover the volume of exploration space and generate small maps with good coverage. The roadmap is constructed out of nodes, each having its own weight. The weight of a given node is calculated using an objective function which measures an approximate view coverage by casting rays from the virtual view and intersecting them with the region of interest. In addition, the weight of a node is increased if this node allows the AUV to see a new side of the region of interest. In each iteration of the algorithm, a node to expand off of is selected based off its location in space or its high weight, a new node with a given amount of freedom is generated, and then added to the roadmap. The algorithm has degrees of freedom in position, pitch, and yaw as well as the objective function to encourage the path to see all sides of the region of interest. Once all sides of the region of interest have been viewed, a path is determined to be complete. The algorithm was tested in a virtual world where the virtual camera acted as the AUV. All of the images collected from our automatically generated path were used to create 3D models and point clouds using photogrammetry. To measure the effectiveness of our paths versus the pre-packaged lawnmower paths, the 3D models and point clouds created from our algorithm were compared to those generated from running a standard lawnmower pattern. The paths generated by our algorithm captured images that could be used in a 3D reconstruction which were more detailed and showed better coverage of the region of interest than those from the lawnmower pattern.
4

The Problems of Generating Sufficient Revenue in a Rapidly Growing Small Community

Memmott, Jeffery L. 01 May 1979 (has links)
The purpose of this study is to analyze the impact of rapid growth on the various revenue and expenditure categories at the local level. A model is presented to project local revenues and expenditures based upon projected per capita income, population, and average daily attendance. The model is based upon previous models from a review of the literature with modification and additions by the author. Revenues and expenditures are estimated simultaneously reflecting the budgetary process at the local level. Coefficients in the model are estimated using sample data from Duchesne and Uintah counties. These coefficients are then used to project the effects of oil shale development in the region. Different policies and changes in current policies are presented to lessen or alleviate the adverse impacts of rapid growht on local cities and school districts.
5

Validation and application of a highly discriminating and rapid 10-locus Y-STR DNA profiling system

Kasu, Mohaimin January 2019 (has links)
Philosophiae Doctor - PhD / DNA profiling the male specific region on the Y-chromosome is fundamental to forensic practise. Its recognised as a powerful analytical tool for investigation of sexual assault when the DNA evidence is highly admixed. Standard practises for processing sexual assault evidence include physically separate the sperm cell from the female fraction using differential extraction followed by autosomal DNA profiling. However, under specific scenarios of assault physical separation may not be possible due to the nature of the evidence. The research presented in this thesis was focused on the development and validation of the UniQTyper™ Y-10 prototype for male specific DNA profiling. The prototype which contains 10 Y-STR markers was developed and validated to deliver a rapid and cost-effective system while maintaining a forensic applicable level of performance. An allelic ladder is produced with an allele cloning approach for which an overview of the workflow and technicalities presented herein is aimed to assists an efficient bulk production process. In a second component novel sequence variation was reported across 153 sequenced alleles and submitted to Genbank. In this output the Y-STR panel was perused beyond the scope of length polymorphisms. In a proof of concept, its potential to discriminate between shared allele sizes by characterizing sequence structure variations is discussed. In a final component we generate the largest Y-STR survey across South Africa to establish reference data and to comprehensively assess the forensic genetics parameters for the UniQTyper™ Y-10.
6

An efficient algorithm for nonlinear integer programming

Moepya, Stephen Obakeng 02 November 2011 (has links)
M.Sc., Faculty of Sciences, University of the Witwatersrand, 2011 / Abstract This dissertation is concerned with discrete global optimization of nonlinear problems. These problems are constrained and unconstrained and are not easily solvable since there exists multiplicity of local and global minima. In this dissertation, we study the current methods for solving such problems and highlight their ine ciencies. We introduce a new local search procedure. We study the rapidly-exploring random tree (RRT) method, found mostly in the research area of robotics. We then design two global optimization algorithms based on RRT. RRT has never been used in the eld of global optimization. We exploit its attractive properties to develop two new algorithms for solving the discrete nonlinear optimization problems. The rst method is called RRT-Optimizer and is denoted as RRTOpt. RRTOpt is then modi ed to include probabilistic elements within the RRT. We have denoted this method by RRTOptv1. Results are generated for both methods and numerical comparisons are made with a number of recent methods.
7

Susceptibilidade antimicrobiana e tipagem molecular de Mycobacterium fortuitum isoladas de amostras clínicas de origem humana / Antimicrobial susceptibility and molecular typing of Micobacterium fortuitum isolated from clinical specimens of human origin

Schiavo, Wesley 06 November 2012 (has links)
Introdução: A revisão da literatura disponível no PubMed evidencia que há relatos de surtos de infecções por micobactérias de crescimento rápido ocorridos no Brasil, mas não há dados nacionais que permitam orientar o tratamento empírico até que o perfil de sensibilidade e a identificação da espécie estejam disponíveis. Não há estudo nacional com amostragem significativa de M. fortuitum nem tampouco análise da relação clonal entre isolados de vários pontos do território nacional. Este trabalho pretende trazer contribuições quanto ao entendimento da disseminação de clones de M. fortuitum no Brasil, assim como o perfil de sensibilidade dessa espécie no Brasil. Material e métodos: Foram utilizadas no estudo 121 isolados pertencentes ao banco de micobactérias do Fleury Medicina e Saúde, referentes ao período de janeiro de 2001 a dezembro de 2010. A identificação da espécie for determinada por sequenciamento parcial do gene rpoB, a clonalidade foi avaliada por eletroforese em campos alternados e a susceptibilidade antimicrobiana foi avaliada utilizando-se placas de microdiluição RAPMYCOI. Resultados e conclusões: Foram detectados três grupos clonais, sendo dois presentes na cidade de Campinas e o terceiro na cidade de Florianópolis. Foi observada a persistência do grupo clonal MFBRA2 na cidade de Campinas por seis anos. A maioria dos casos isolados em diferentes estados brasileiros pertence a grupos clonais distintos. O índice de similaridade de Dice mínimo para a identificação de um grupo clonal de M. fortuitum ao analisar fragmentos de restrição gerados por XbaI deve ser de 98%. Todos os isolados testados foram sensíveis à amicacina, tigeciclina, imipenem, ciprofloxacina, moxifloxacina, sulfametoxazol-trimetoprim e linezolida, o que permite seu uso no tratamento empírico das infecções por M. fortuitum. Houve uma baixa taxa de sensibilidade à doxiciclina o que não subsidia seu uso em tratamento empírico. A taxa de sensibilidade de 89% para claritromicina não permite seu uso empírico no tratamento das infecções por M. fortuitum. / Introduction: The literature available on PubMed shows that there are reports of outbreaks of infections caused by rapidly growing mycobacteria occurred in Brazil, but there is no national data to guide empiric treatment until the susceptibility profile and identification of the species are available. No national study of significant sample of M. fortuitum nor analysis of the clonal relationship between isolates from various parts of the country. This work aims to bring contributions to the understanding of the spread of clones of M. fortuitum in Brazil, as well as the susceptibility pattern of this species in Brazil. Material and methods: We studied 121 isolates belonging to the mycobacteria collection from Fleury Medicina e Saúde, collected during the period from January 2001 to December 2010. Species identification was determined by partial sequencing of the rpoB gene, clonality was assessed by pulsed field gel electrophoresis and antimicrobial susceptibility was assessed using microdilution plates RAPMYCOI. Results and conclusions: There were three clonal groups, with two present in the city of Campinas and the third in Florianopolis. We observed the persistence of the clonal group MFBRA2 in Campinas for six years. Most cases isolated in different Brazilian states belong to different clonal groups. Our data indicate that Dice\'s similarity index for identification of a M. fortuitum clonal group should be at least 98% when analyzing restriction fragments generated by XbaI. All isolates tested were susceptible to amikacin, tigecycline, imipenem, ciprofloxacin, moxifloxacin, linezolid, and trimethoprim-sulfamethoxazole, which allows its use in the empirical treatment of infections caused by M. fortuitum. There was a low sensitivity to doxicycline which does not subsidize its use in empiric treatment. The rate of 89% sensitivity does not allow the empirical use of clarithromycin in the treatment of infections caused by M. fortuitum.
8

A one-dimensional Boussinesq-type momentum model for steady rapidly varied open channel flows

Zerihun, Yebegaeshet Tsegaye Unknown Date (has links)
The depth-averaged Saint-Venant equations, which are used for most computational flow models, are adequate in simulating open channel flows with insignificant curvatures of streamlines. However, these equations are insufficient when applied to flow problems where the effects of non-hydrostatic pressure distribution are predominant. This study provides a comprehensive examination of the feasibility of a simple one-dimensional Boussinesq-type model equation for such types of flow problems. This equation, which allows for curvature of the free surface and a non-hydrostatic pressure distribution, is derived using the momentum principle together with the assumption of a constant centrifugal term at a vertical section. Besides, two Boussinesq-type model equations that incorporate different degrees of corrections for the effects of the curvature of the streamline are investigated in this work. One model, the weakly curved flow equation model, is the simplified version of the flow model based on a constant centrifugal term for flow situations that involve weak streamline curvature and slope, and the other, the Boussinesq-type momentum equation linear model is developed based on the assumption of a linear variation of centrifugal term with depth.
9

A one-dimensional Boussinesq-type momentum model for steady rapidly varied open channel flows

Zerihun, Yebegaeshet Tsegaye Unknown Date (has links)
The depth-averaged Saint-Venant equations, which are used for most computational flow models, are adequate in simulating open channel flows with insignificant curvatures of streamlines. However, these equations are insufficient when applied to flow problems where the effects of non-hydrostatic pressure distribution are predominant. This study provides a comprehensive examination of the feasibility of a simple one-dimensional Boussinesq-type model equation for such types of flow problems. This equation, which allows for curvature of the free surface and a non-hydrostatic pressure distribution, is derived using the momentum principle together with the assumption of a constant centrifugal term at a vertical section. Besides, two Boussinesq-type model equations that incorporate different degrees of corrections for the effects of the curvature of the streamline are investigated in this work. One model, the weakly curved flow equation model, is the simplified version of the flow model based on a constant centrifugal term for flow situations that involve weak streamline curvature and slope, and the other, the Boussinesq-type momentum equation linear model is developed based on the assumption of a linear variation of centrifugal term with depth.
10

Land for the Dead : Access to and Evolvement of Necral Land in Dar es Salaam, Tanzania

Eriksson, Pontus January 2010 (has links)
<p>This thesis is aiming to describe and understand the access to and evolvement of necral land (burial and crematory grounds) in Dar es Salaam, the largest city in Tanzania and one of the most rapid growing cities in Africa. The study is based on field work conducted in Kinondoni District during the spring of 2010. It could partly be described as intensive research, because it is done like a pioneer study, trying to describe and understand a phenomena; not so much trying to find out how widespread the phenomena is. The data was primarily produced through interviews with persons representing different actors. The result from the field study is that even if there are differences in costs and needs for permits to access the land, it seems like there are ways for everyone to bury or cremate a dead body. One common way of manage costs is to collect financial contributions from friends, family and neighbours. The problem however is the evolvement, where centrally located burial grounds are considered full but still used and the cemetery established by the municipality outside the centre is not used by city dwellers, because of the lack of information and the transportation cost.</p>

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