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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

A proteomic analysis of Klebsiella oxytoca SYSU-011 after exposure to tetracyanonickelate(II)

Chen, Wen-jen 19 August 2008 (has links)
Klebsiella oxytoca SYSU-011 isolated from wastewater of a metal-plating plant in southern Taiwan had been proven to be able to degrade cyanide. In this study, we performed proteomic analyses to understand the mechanism of tetracyanonickelate (TCN) resistance in K. oxytoca by using two-dimensional polyacrylamide gel electrophoresis (2-D PAGE) and MALDI-TOF-MS techniques. There were 91 protein spots had been induced or overexpressed (≥2 fold) by TCN. Among them, 44 protein spots were successfully identified by MALDI-TOF-MS. The expressed proteins that had been escalated including chaperone, glutathione S-transferase (GST) and alkyl hydroperoxide reductase (AHR) were involved in the TCN detoxification process. Fructose-bisphosphate aldolase, glyceraldehyde-3-phosphate dehydrogenase, phosphoglucomutase and 6-phosphogluconolactonase were involved in energy-producing process; nitrogenase and glutamine synthetase (GS) were required to regulate nitrogen assimilation. We also analyzed the K. oxytoca membrane proteins. Twenty six proteins spots had been successfully identified by MALDI-TOF-MS (out of 41 protein) that were induced ≥2 fold by TCN. These proteins induced RND-drive efflux proteins (RND family, MFP subunit, outer membrane factor A and outer membrane factor TolC) and cation efflux system. These efflux pumps could transport nickel ion out of the cells. The induced ATP-binding cassette (ABC) proteins may also play a role in transportation of metal-cyano complexes TCN and nutrition. By this study, we had a better understanding on the defense mechanism of K. oxytoca after exposure to TCN.
2

An Evaluation of NAPL Wettability in 2-D Visualization Experiments

SAINT AIME, Ricot 01 December 2011 (has links)
The presence of light non-aqueous phase liquid (LNAPL) in the subsurface constitutes a long-term source of pollution for groundwater. Hence understand the movement of NAPL in the subsurface is essential in order to design effective remediation technology. Their movement in the subsurface is so complex that researchers have been using different media, different NAPLs, and conducted experiments in 1-D column, 2-D tank and 3-D tank in order to study the phenomenon. To solve the problem of limitation in flow boundaries in 1-D researchers have used two dimensional (2-D) tanks made of glass and plexiglass. However there have been some questions concerning the possible impact of NAPL wettability on materials use to construct the tank. This wettability may influence the flow of fluids at the visual interface. A representative LNAPL (dodecane) was released in the vadose zone of an Ottawa sand. Two external constant head reservoirs were used to maintain a constant water table in the tank. Time-series digital images of plume were used to analyze the geometry and position of the plume in the tanks regarding to the water table. Then relative geometry of the LNAPL was compared to Pantazidou and Sitar's equation. In both the sand and the glass tank, water is the wetting fluid, whereas dodecane (LNAPL) is the non-wetting fluid. However, on the plexiglass the LNAPL is the wetting fluid. As a result 40% and 70% difference were observed between glass and plexiglass tanks regarding the length and the thickness, and the area was twice the size of the plume in the glass tank. This demonstrates that the tank material is an important parameter to be considered on flow visualization of NAPL. Moreover, the influence of ethanol on dodecane was tested on a 2-D tank in glass. The results showed that the presence of ethanol appears to influence on the size and position of the plume in the subsurface.
3

Fast visual inspection for quality control

Mehenni, B. January 1989 (has links)
No description available.
4

Restauração de imagens médicas utilizando o filtro de Kalman / not available

Mello, Edson Batista de 13 October 1998 (has links)
Neste trabalho técnicas de restauração de imagens aplicadas à filtragem de imagens médicas foram estudadas. Considera-se uma abordagem recursiva de filtragem e suas diversas implementações em duas dimensões. A implementação utilizada neste trabalho foi a do filtro de Kalman de atualização reduzida (RUKF). Na implementação do filtro de Kalman de atualização reduzida um quarto de plano (QP) foi tomado como região de suporte e um modelo autoregressivo bidimensional (AR 2-D) foi utilizado como modelo de imagem. Os parâmetros do modelo AR 2-D e a variância do ruído foram encontrados através de uma implementação do algoritmo de Levinson para duas dimensões baseada no algoritmo de Levinson em configuração multicanal. A ordem do modelo AR 2-D foi determinada pelo critério de informação de Akaike (AIC). Para análise de resultados o filtro de Kalman de atualização reduzida foi aplicado em uma imagem planar, considerada invariante no espaço e com ruído ele observação não estacionário, e os resultados comparados àqueles obtidos com o filtro de Wiener. / In this work image restoration techniques for the filtering of medicai images are studied. Emphasis is given to the recursive approach to image restoration and its different implementations are described. The implementation used in the restoration procedure is the reduced update Kalman filter (RUKF). In the implementation of the reduced update Kalman filter a quarter plane is adopted as the region of support and a 2-D autoregressive (AR) model is used as the image model. The parameters of the 2-D AR model and the variance of the driving noise are found by a 2-D implementation of the Levinson algorithm. The model order of the 2-D AR model is determined by the Akaike information criterion (AIC). For the analysis of the results, the reduced update Kalman filter is applied to a space invariant plane image with nonstationary noise. The results are compared to the results of the Wiener filter.
5

Restauração de imagens médicas utilizando o filtro de Kalman / not available

Edson Batista de Mello 13 October 1998 (has links)
Neste trabalho técnicas de restauração de imagens aplicadas à filtragem de imagens médicas foram estudadas. Considera-se uma abordagem recursiva de filtragem e suas diversas implementações em duas dimensões. A implementação utilizada neste trabalho foi a do filtro de Kalman de atualização reduzida (RUKF). Na implementação do filtro de Kalman de atualização reduzida um quarto de plano (QP) foi tomado como região de suporte e um modelo autoregressivo bidimensional (AR 2-D) foi utilizado como modelo de imagem. Os parâmetros do modelo AR 2-D e a variância do ruído foram encontrados através de uma implementação do algoritmo de Levinson para duas dimensões baseada no algoritmo de Levinson em configuração multicanal. A ordem do modelo AR 2-D foi determinada pelo critério de informação de Akaike (AIC). Para análise de resultados o filtro de Kalman de atualização reduzida foi aplicado em uma imagem planar, considerada invariante no espaço e com ruído ele observação não estacionário, e os resultados comparados àqueles obtidos com o filtro de Wiener. / In this work image restoration techniques for the filtering of medicai images are studied. Emphasis is given to the recursive approach to image restoration and its different implementations are described. The implementation used in the restoration procedure is the reduced update Kalman filter (RUKF). In the implementation of the reduced update Kalman filter a quarter plane is adopted as the region of support and a 2-D autoregressive (AR) model is used as the image model. The parameters of the 2-D AR model and the variance of the driving noise are found by a 2-D implementation of the Levinson algorithm. The model order of the 2-D AR model is determined by the Akaike information criterion (AIC). For the analysis of the results, the reduced update Kalman filter is applied to a space invariant plane image with nonstationary noise. The results are compared to the results of the Wiener filter.
6

2-D Epithelial Tissues, Cell Mechanics, and Voronoi Tessellation

Olaranont, Nonthakorn 25 April 2019 (has links)
In this thesis, we develop a new computational method using Voronoi vertex model and energy to describe the cell-cell interaction among the epithelial tissue. Several studies and simulations will be showed such as equilibrium states, wound closure process, and abnormal growth. We also perform analysis on circular epithelial wound closure process.
7

2-D Epithelial Tissues, Cell Mechanics, and Voronoi Tessellation

Olaranont, Nonthakorn 25 April 2019 (has links)
In this thesis, we develop a new computational method using Voronoi vertex model and energy to describe the cell-cell interaction among the epithelial tissue. Several studies and simulations will be showed such as equilibrium states, wound closure process, and abnormal growth. We also perform analysis on circular epithelial wound closure process.
8

Bartonella Clarridgeiae: Invasion of Human Microvascular Endothelial Cells and Role of Flagella in Virulence

Whitney, Anne M. 14 April 2009 (has links)
B. henselae, B. bacilliformis and B. quintana are capable of causing vasoproliferative diseases in humans by modulating apoptosis and proliferation of endothelial cells. Bartonella clarridgeiae, a close relative of the pathogenic Bartonellae, has been implicated in human disease but has not yet been isolated from a human patient. Both B. bacilliformis and B. clarridgeiae have flagella and a flagellar type 3 secretion system, while B. henselae and B. quintana do not. We created 2 non-motile mutants of B. clarridgeiae by interrupting the flagellin gene, flaA, or the flagellar motor genes, motBC. We investigated whether B. clarridgeiae could invade human endothelial cells (HMECs) and if functional flagella were important for invasion. The non-motile mutants and the wild-type strain were capable of entering HMECs in vitro. The flaA mutant was deficient in attachment, but the HMECs in culture with the flaA mutant demonstrated increased proliferation. The motBC mutant showed enhanced invasion. Differential secretion of proteins was revealed by 2-D electrophoresis and MALDI-TOF analysis of secretomes from the co-cultures compared to uninfected HMECs. HMECS infected with wild-type B. clarridgeiae secreted proteins indicative of proliferation. The flaA mutant induced the secretion of proteins involved in cytoskeletal rearrangement, cell migration, and proliferation. The motBC-infected HMECs showed signs of hypoxia. The co-chaperonin GroES was found in higher concentration in the supernatant of the hyper-invasive motBC strain/HMEC co-culture than the wild-type co-culture and was found at a very low concentration in the flaA culture supernatant. Cross-talk between secretion systems is suggested.
9

Development of High Accuracy 2-D Inspection Software

Hung, Tzu-Yu 15 August 2000 (has links)
The CCD sensors have the advantage for small size clear image and low prices, It is the image capture unit of computer-vision system which developed fast in the past years, especially in the 2-D image capture CCD sensors are better then another sensors, so in the industry it be used on products detection . There are two different sections on using CCD sensors to detect products,the first section is about the detection of what kind of objects amount of objects and position of objects, the second section is about looking for lines ¡Bcircles ¡Bareas of objects¡Bdiameter¡Bcircularity and the angles between two lines The research purpose is finding a high accuracy algorithmic with low complicacy and high accuracy conditions; the accuracy can reach the sub-pixel accuracy with low price facilities and high speed .
10

Application of 2-dimensional video analysis by competitive swimming coaches to monitor fatigue in breaststroke technique during training

Thow, Jacqueline Laura January 2016 (has links)
In swimming, technical performance is a vital indicator of successful performance; however, during phases of high-intensity training, technique can be negatively influenced by fatigue. Advances in video technology have made it possible to increase coaches’ capacity to monitor athletes’ technical performances during training. Yet research examining the biomechanical responses that occur with fatigue using video methods, which are applicable and relevant to coaches during training, is scarce. The limited research to date that has examined the biomechanical responses that occur with fatigue has been restricted to examining fatigue during race-like situations and have used technology which is not available for use by coaches during training. Whilst this research indicates that changes occur during races, it does not apply to coaches for use during training. As fatigue, and its management, is a vital component of the training process, identifying a method of monitoring fatigue during training, which is applicable to coaches, is essential for athlete development. This research is therefore intended to address this by exploring the implications of 2-dimensional (2-D) video analysis in the management of fatigue, during training, by competitive swimming coaches. To explore this, this thesis comprises of four studies. The aim of the first study was to investigate whether 2-D video analysis methods currently used by coaches can measure data validly and reliably. To achieve this, the accuracy, precision, reliability and validity of thirty-five variables (thirty-four technical measures and swim time) were calculated using Dartfish Pro Suite motion analysis software, version 6.0 (Dartfish Ltd, Fribourg, Switzerland) and compared to the smallest worthwhile change. By calculating and comparing these measures, only those technical variables which can be measured with accuracy and precision could be determined objectively. A series of fifteen variables (fourteen technical measures and swim time) were found to be precise, valid and reliable when measured using Dartfish Pro Suite motion analysis software, version 6.0. Using the previously established technical measures, the aim of the second study was to assess if these measures can determine whether technical changes can occur during a high-intensity training session. To achieve this, a group of seventeen elite breaststroke swimmers completed a standard swim set. This involved repeating maximal effort 100m swims on a limited swim-rest time, designed to induce a fatigued state representative of high-intensity training conditions. To determine whether technical changes as a result of fatigue could be detected, the fourteen kinematic technique variables and swim time (fifteen dependent variables in total) were recorded and analysed using 2-D Dartfish Pro Suite motion analysis software, version 6.0 from video recordings of the first and last 100m swim of each swimmer. In addition, 95% confidence intervals were determined to investigate any commonalities or individual differences among swimmers in changes in technical parameters. It was found that during one high-intensity session, technical changes can occur in a group of elite swimmers. The largest changes were shown in leg glide duration (64.6%), swim time (33.2%), stroke rate (35.3%), stroke length (-29.2%), and average velocity (-10.2%) and were shown to have statistically significant (p < 0.05) differences between the first and last 25m of the swim set. These changes were also shown to be common amongst all swimmers and occurred early in the swim set. To evaluate coaches understanding of fatigue and its management during training, the aim of the third study was to assess coaches’ current practices and knowledge regarding fatigue during training. To achieve this, a questionnaire was distributed to over 370 coaches throughout the UK. The questionnaire was separated into multiple sections which assessed: coaches’ current understanding of the topic of fatigue; the methods coaches’ employ to monitor fatigue during a training session; and the processes used to manage fatigue during the training process. It was found that up to 98% of the coaches consider fatigue, its effect and management important in the development of their swimmers. Despite this, there is a lack of consistency in knowledge and methods used by coaches to monitor this. As a result, coaches are continuing to use traditional methods to monitor their athletes which are quick and reliable, specifically stopwatches (100%) and visual observation (98%). Due to the predominant use of visual observation to monitor fatigue, and the identification of technical changes with fatigue, the aim of the fourth study was to assess whether coaches could visually identify changes in the previously established technical markers and whether this could be improved through education of fatigue and video analysis methods. To achieve this, two groups of ten competitive swimming coaches observed a series of videos of three swimmers taken pre- and post- training, and were asked to identify any technical factors which they perceived to change. One group underwent an intervention using Dartfish Pro Suite motion analysis software, version 6.0 and underwater analysis to assess whether this improved their ability to visually observe fatigue in elite swimmers. The remaining group of coaches acted as a control group and received no feedback. Following the one hour intervention, the coaches’ observations slightly improved, however this improvement was not statistically significant (p > 0.05) nor retained after 4 weeks. Although the coaches’ perceptions of fatigue during training varied, they did show a keen interest in further training and education on fatigue and 2-D video analysis. The results from this research indicate that 2-D video analysis is an effective and useful tool, which has practical applications: in monitoring fatigue during a training session; guiding training programmes to maximise training potential; and developing coaches’ identification and management of fatigue during training through education programmes.

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