This doctoral thesis deals with biophysical interpretation of quantitative phase imaging (QPI) gained with coherence-controlled holographic microscope (CCHM). In the first part methods evaluating information from QPI such as analysis of shape and dynamical characteristics of segmented objects as well as evaluation of the phase information itself are described. In addition, a method of dynamic phase differences (DPD) is designed to allow more detailed monitoring of cell mass translocations. All of these methods are used in biological applications. In an extensive study of various types of cell death, QPI information is compared with flow cytometry data, and preferably a combination of QPI and fluorescence microscopy is used. The DPD method is used to study mass translocations inside the cell during osmotic events. The simplified DPD method is applied to investigate the mechanism of tumor cell movement in collagen gels.

The main task of this master’s thesis is to design circuits for feedback control of the main drives Minidarpa robot. It contains the description of power-driven mobile robot control theory and the DC motor. The second part deals with the design options of the control module and its mechanical design. The last part of the proposal made cascade speed control with current loop by using optimal module and the symmetric optimum methods.

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No description available.

<p dir="ltr">The aquaculture industry has experienced remarkable expansion over the past few decades, largely due to the development of modern technologies and intensive farming systems. However, as the industry continues to grow, farming-related and environmental stressors such as overcrowding, poor water conditions and handling have continued to pose major obstacles to the worldwide expansion of this sector. The presence of these stressors affect the growth potential and health of farmed animals leading to significant economic losses. Hence, efficient management of the stress response of farmed species via sustainable means is important to ensure continuous development of the aquaculture sector. This study, therefore, explores the potential of dietary tryptophan supplementation to mitigate stress and improve growth, immune response, and disease resistance in channel catfish (<i>Ictalurus punctatus</i>). The study comprised a 36-day feeding trial where juvenile catfish were fed a tryptophan-supplemented diet under stressed (cortisol-supplemented) and unstressed conditions, followed by a 72-hour disease challenge with <i>Aeromonas hydrophila </i>(vAh). At the end of the study, the results show tryptophan supplementation did not significantly enhance growth or nutrient utilization, likely due to its neuroendocrine effects on feed intake. However, tryptophan demonstrated potential in modulating stress physiology and immune responses, including upregulation of key immune-related genes post-infection and promoting survival against vAh infection. These findings suggest that while tryptophan may not directly improve growth in our specific experimental conditions, its role in stress and immune regulation warrants further investigation, particularly in optimizing its dosage and combination with other dietary additives.</p>

The question I address is: how might a theology of authority be conceived in the light of questions raised by what is termed 'post-modernity'? Is it possible to articulate a theology of authority coming to the church community 'from God' that avoids an oppressive and alienating heteronomy? The thesis explores the question of authority as of vital importance in the sociological dimension of religion, calling for legitimisation (in light of claims made for itself) and as obligatory in the theological sphere. For this reason the project involves two methodologies (theological and sociological/ethnographic). While this investigation is relevant to all sections of the Christian church, particular attention is paid to Baptist churches in the UK, since they hold a concept in their tradition that I suggest is valuable in answering the question of the thesis, namely that of covenant. Within the Christian tradition there is an inner 'problematic' relating the personal authority of Christ to the forms of institution (church) and text (scripture). I explore this with a brief survey of theological authority as found in the fourfold foundation of scripture, tradition, reason and experience. From this is developed a brief theological and Christological reflection on divine authority and covenant theology as found in Karl Barth and his response to the 'inner problematic'. Within contemporary culture I view authority through the lens of so-called 'postmodernism', identifying four challenges to the notion of 'external authority' (all of which exemplify a move from the external to internal, and objective to subjective approaches to authority). This is further explored by means of qualitative research with one-to-one interviews conducted in a Baptist church in York. This data is reflected upon by means of ethnography and 'judicious narratives', especially in dialogue with material from Guest ('congregational study'), Heelas and Woodhead ('subjectivised-self') and Healy ('theodramatic horizon' and 'practical-prophetic ecclesiology'), providing an intersection between the language of theology and sociology. The concept of church as covenant community is explored in Baptist and (more briefly) Anglican traditions, leading to a constructive proposal that both the inner-church 'problematic' and the 'postmodern' challenge to authority might begin to be resolved with the notion of covenant. It is within this context of relationship, human and divine, that the authoritative and revelatory Word of God, the story that is Christ, is found in community and praxis. Here is a 'triangulating' relationship between authority, story and covenant revealing divine authority in a non-coercive way and relevant to contemporary culture.

‘Net Positive Water’ explores the capability of domestic architecture to combat the developing urban water problem. Urban intensification is contributing to the volatility of urban waters and the breakdown of the urban water cycle. Inhabitant water misuse and overconsumption is overwhelming aging municipal utilities, resulting in the decay of urban water quality. LEEDTM and The Living Building Challenge are recognized Green Building Guidelines prescribing sustainable site and building water standards. Case Studies of domestic Green Building projects will showcase water conservation to enable domestic water renewal. Net Zero Water Guidelines based on the Green Building Guidelines outline Potable and Non-Potable water use to achieve a sustainable volume of water demand at 70 litres per capita per day. Sustainable water practices are encouraged by utilizing domestic building systems to increase water value and water awareness. Time-of-Use and Choice-of-Use exposure for household water related tasks establish water savings through the use of best-performing water fixtures and appliances. Net Positive Water Guidelines will establish On-site and Building standards for sustainable harvesting and storage of water resources. Clean and Dirty water management will prescribe Passive design and Active mechanical processes to maintain best-available water quality in the urban domestic environment. Net Positive Water building typology will integrate urban inhabitation as a functional component of the urban water cycle to use, reuse, and renew water resources. The method will be tested using a Mid-rise Pilot project to deploy the necessary Passive and Active mechanisms to generate Net Positive Water quality through Net Zero Water sustainable water use. The pilot project is situated in Waterfront Toronto - The Lower Don Lands development to harness regional interests for water renewal and environmental revitalization.

Job insecurity in the workplace has become an increasingly important trend in organisational research. The appraisal of job insecurity by individuals plays a significant part in how reactions manifest in the experiences of workplace stressors, job satisfaction, positive and negative work attributes and social support. However, there is a lack of research regarding specific workplace stressors at work leading to certain outcomes like safety behaviour, turnover intention and mental health, especially within a South African working context. Job insecurity has also been classified as a workplace stressor. The existence of other stressors tends to increase the ultimate effect of insecurity for the individual. The attempts from organisational management to manage this phenomenon are therefore crucial in decreasing the negative effects of job insecurity and increasing the productivity of the organisation. In order to measure the job insecurity levels of employees, it is important to make use of valid and reliable job insecurity measures. An absence of empirical research on validity and reliability studies in terms of job insecurity in South African is evident. The main objectives of this research were: 1) to establish the psychometric properties of a measure of job insecurity in a selected gold mining company in South Africa; 2) to determine the influence of job insecurity and work stress (i.e. role conflict, clarity and overload) on worker safety performance and if coping could moderate this; 3) to investigate the theoretical and empirical relationships between job stressors (task completion ambiguity and task quality ambiguity), competency demands, employability perceptions, job satisfaction and turnover intention over time, and 4) to investigate if social support has a mediating effect between positive interpersonal attributes, negative interpersonal attributes, job insecurity and subsequent health. To achieve the first objective, a cross-sectional design was used (N = 566), including various business units of a South African-based gold mining company. The assessment of the psychometric properties of a measure of quantitative and qualitative job insecurity for employees was determined through construct (structural) equivalence, exploratory factor analysis and multivariate analysis of variance to calculate the comparison of the factor structure for the different cultural groups. For qualitative job insecurity, the scale shows low equivalence for the African languages group. Statistically significant differences were found between the levels of job insecurity of employees in terms of gender. The second objective, concerning the investigation into the relationship of work stress and job insecurity with unsafe behaviour at work, was achieved with across-sectional survey design (N = 771). The hypothesised model included the influence of role conflict, role ambiguity, role overload, and job insecurity on unsafe work behaviour. Coping was introduced as a moderator in this relationship. The results indicated that when employees experience work stress and job insecurity, their safety compliance is low. This relationship was also moderated by a coping strategy of Avoidance. To achieve the third objective, a longitudinal study was conducted and data was gathered by means of an electronic survey, with 771 employees participating at Time 1, and 345 participating at Time 2. Results for predicting employees’ turnover intentions, experience of task completion and quality ambiguity, external employability and job satisfaction made a direct contribution in predicting their turnover intention. No mediating role of job satisfaction between job stressors, competency demands and employability perceptions on the one hand and turnover intentions on the other hand, were found. Addressing the fourth objective in investigating the moderating role of social support between the relationship of experiencing positive interpersonal (communication with the manager and feedback), negative interpersonal experiences (powerlessness and interpersonal conflict), job insecurity (quantitative and qualitative) and health, was met with a longitudinal random sample of employees in different business units in one selected multi-national mining company based in South Africa (N = 771). Results for these employees indicated that all the proposed variables, except feedback from the manager, were statistically significantly related to health. No moderating effect for social support could be found over time, but it was shown that interpersonal conflict at work is a longitudinal predictor of employee health. By way of conclusion, the implications of the research were discussed and recommendations for managers and for future research were made. / Thesis (PhD (Industrial Psychology))--North-West University, Potchefstroom Campus, 2013.

Job insecurity in the workplace has become an increasingly important trend in organisational research. The appraisal of job insecurity by individuals plays a significant part in how reactions manifest in the experiences of workplace stressors, job satisfaction, positive and negative work attributes and social support. However, there is a lack of research regarding specific workplace stressors at work leading to certain outcomes like safety behaviour, turnover intention and mental health, especially within a South African working context. Job insecurity has also been classified as a workplace stressor. The existence of other stressors tends to increase the ultimate effect of insecurity for the individual. The attempts from organisational management to manage this phenomenon are therefore crucial in decreasing the negative effects of job insecurity and increasing the productivity of the organisation. In order to measure the job insecurity levels of employees, it is important to make use of valid and reliable job insecurity measures. An absence of empirical research on validity and reliability studies in terms of job insecurity in South African is evident. The main objectives of this research were: 1) to establish the psychometric properties of a measure of job insecurity in a selected gold mining company in South Africa; 2) to determine the influence of job insecurity and work stress (i.e. role conflict, clarity and overload) on worker safety performance and if coping could moderate this; 3) to investigate the theoretical and empirical relationships between job stressors (task completion ambiguity and task quality ambiguity), competency demands, employability perceptions, job satisfaction and turnover intention over time, and 4) to investigate if social support has a mediating effect between positive interpersonal attributes, negative interpersonal attributes, job insecurity and subsequent health. To achieve the first objective, a cross-sectional design was used (N = 566), including various business units of a South African-based gold mining company. The assessment of the psychometric properties of a measure of quantitative and qualitative job insecurity for employees was determined through construct (structural) equivalence, exploratory factor analysis and multivariate analysis of variance to calculate the comparison of the factor structure for the different cultural groups. For qualitative job insecurity, the scale shows low equivalence for the African languages group. Statistically significant differences were found between the levels of job insecurity of employees in terms of gender. The second objective, concerning the investigation into the relationship of work stress and job insecurity with unsafe behaviour at work, was achieved with across-sectional survey design (N = 771). The hypothesised model included the influence of role conflict, role ambiguity, role overload, and job insecurity on unsafe work behaviour. Coping was introduced as a moderator in this relationship. The results indicated that when employees experience work stress and job insecurity, their safety compliance is low. This relationship was also moderated by a coping strategy of Avoidance. To achieve the third objective, a longitudinal study was conducted and data was gathered by means of an electronic survey, with 771 employees participating at Time 1, and 345 participating at Time 2. Results for predicting employees’ turnover intentions, experience of task completion and quality ambiguity, external employability and job satisfaction made a direct contribution in predicting their turnover intention. No mediating role of job satisfaction between job stressors, competency demands and employability perceptions on the one hand and turnover intentions on the other hand, were found. Addressing the fourth objective in investigating the moderating role of social support between the relationship of experiencing positive interpersonal (communication with the manager and feedback), negative interpersonal experiences (powerlessness and interpersonal conflict), job insecurity (quantitative and qualitative) and health, was met with a longitudinal random sample of employees in different business units in one selected multi-national mining company based in South Africa (N = 771). Results for these employees indicated that all the proposed variables, except feedback from the manager, were statistically significantly related to health. No moderating effect for social support could be found over time, but it was shown that interpersonal conflict at work is a longitudinal predictor of employee health. By way of conclusion, the implications of the research were discussed and recommendations for managers and for future research were made. / Thesis (PhD (Industrial Psychology))--North-West University, Potchefstroom Campus, 2013.

‘Net Positive Water’ explores the capability of domestic architecture to combat the developing urban water problem. Urban intensification is contributing to the volatility of urban waters and the breakdown of the urban water cycle. Inhabitant water misuse and overconsumption is overwhelming aging municipal utilities, resulting in the decay of urban water quality. LEEDTM and The Living Building Challenge are recognized Green Building Guidelines prescribing sustainable site and building water standards. Case Studies of domestic Green Building projects will showcase water conservation to enable domestic water renewal. Net Zero Water Guidelines based on the Green Building Guidelines outline Potable and Non-Potable water use to achieve a sustainable volume of water demand at 70 litres per capita per day. Sustainable water practices are encouraged by utilizing domestic building systems to increase water value and water awareness. Time-of-Use and Choice-of-Use exposure for household water related tasks establish water savings through the use of best-performing water fixtures and appliances. Net Positive Water Guidelines will establish On-site and Building standards for sustainable harvesting and storage of water resources. Clean and Dirty water management will prescribe Passive design and Active mechanical processes to maintain best-available water quality in the urban domestic environment. Net Positive Water building typology will integrate urban inhabitation as a functional component of the urban water cycle to use, reuse, and renew water resources. The method will be tested using a Mid-rise Pilot project to deploy the necessary Passive and Active mechanisms to generate Net Positive Water quality through Net Zero Water sustainable water use. The pilot project is situated in Waterfront Toronto - The Lower Don Lands development to harness regional interests for water renewal and environmental revitalization.