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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.
61

Detection And Characterization Of Plant Genes Involved In Various Biotic And Abiotic Stress Conditions Using Ddrt-pcr And Isolation Of Interacting Proteins

Unver, Turgay 01 August 2008 (has links) (PDF)
The main objective of this thesis dissertation is functionally characterizing the genes involved in biotic and abiotic stresses of plants at molecular level. Previously, upon pathogen attack Rad6 gene expression was found to be changed in wheat and barley plants. To functionally characterize the Rad6 gene, VIGS (Virus induced gene silencing) system was used. HR (Hypersensitive response) like symptoms was detected in every silenced barley and wheat plants. To figure out, transcriptomes and proteomes of Rad6 silenced plants were analyzed. 2-D PAGE analysis was also performed on silenced and control wheat plants. No pathogen growth was observed in Rad6 silenced barley lines. Additionally, the susceptible wild type Arabidopsis plants showed resistant phenotype when any of the Rad6 gene copies is mutated. This suggests that Rad6 gene has a negative regulatory role in plant disease resistance which was proved for the first time. Yeast two hybrid protein interaction study suggests that RAD6 carrying out its function by interacting with SGT1 protein and regulating resistance related genes. It has been first time reported in this thesis that E2 (Ubiquitin conjugating enzyme) takes role in plant disease resistance. Boron which is the other consideration in the scope of thesis as an abiotic stress factor at a very limited amount is necessary for the normal development of plants. This study is conducted on highly boron tolerant Gypsophila perfoliata L. collected from a location in the boron mining area. The plant samples were tested in the presence of high boron (35 mg/kg) concentrations. The transcriptomes of the plant samples treated with the excess levels of boron to that of the samples grown under normal concentration were compared using differential display PCR method. Thirty bands showing differential expression levels at varying time points were analyzed. 18 of them were confirmed via qRT-PCR.
62

Elucidation Of The Role Of Gcn2 Gene In Response To Powdery Mildew Infection

Ozturk, Ibrahim Kutay 01 August 2012 (has links) (PDF)
Plant immune system is entirely based on the immunities of the individual cells in which systemic signals originate from the infection sites. Powdery mildew disease is one of the agents causing these infection sites, resulting in significant yield losses, if disease develops. Understanding the molecular basis of plant-pathogen interactions is the new trend for fighting against plant pathogens, since classical methods used in selection of resistant plants are becoming less and less efficient nowadays. Thus, finding out the genes which are responsible in plant&rsquo / s resistance is becoming very important. In this thesis, effect of &lsquo / General Control Nondepressible-2&rsquo / (GCN2) homolog protein in barley defense mechanism was aimed to be studied. The GCN2 of yeast was v previously identified in our laboratory as an interacting protein when the yeast cDNA library was screened with a putative yellow rust R gene (Yr10) fragment. There are reports available in the literature for the function of GCN2 protein, which makes it a good candidate for a role in disease resistance. Thus, the barley homologue of GCN2 might have a role in the R protein mediated early disease response of which may be proceeding via Programmed Cell Death (PCD). In order to observe such function of HvGCN2 in barley, silencing of its expression via Virus Induced Gene Silencing (VIGS) was investigated. Therefore, the GCN2 homologue was found to function as dampening the severity of the disease. The silencing with triple technical replicates was observed in 5 of the 6 samples, at an average of 43.2% by qRT-PCR analysis. The pathogen growth levels at different time points were analyzed under light microscope on the silenced and the control samples by measuring the primary and secondary hyphae lengths. The total of 24 seedlings and 292 individual spores were analyzed, and then the level of disease formation was quantitated with 603 primary hyphae and 106 secondary hyphae measurements. Up to 25% hyphae growth rate differences between the control and silenced groups were observed with a probability value less than 0.05 on t-test.
63

MIV-positiewe huiswerksters se konstruering van hul ervarings van MIV en VIGS binne die werkgewersgesin (Afrikaans)

Barnard, Jakoba Petronella 11 March 2005 (has links)
This study focused on HIV-positive domestic helpers and the constructions of their experiences in their employing families. A literature survey established the primary theoretical assumption for the study that acknowledges the domestic helper as an integral part of the extended family of the employer. The study sought to generate grounded theory through content analysis, qualitative research methods and the constructivist-interpretative paradigm. Semi-structured interviews with open questions were conducted with 14 HIV-positive domestic helpers. Responses captured in audio recordings were transcribed and analysed. The textual data was then analysed and interpreted based on open, axial and selective coding. From this coding process four themes emerged as the ways in which HIV-positive domestic helpers construct their experiences within the families. The results from this study indicate that they construct their experiences around: <ul> <li> the HIV&AIDS diagnosis, </li> <li> their HIV&AIDS status, </li> <li> their emotions and </li> <li> their needs. </li></ul> A particularistic scrutiny of the data and research results indicate that participants experience that visible symptoms of HIV&AIDS may forewarn employers when domestic helpers are HIV-positive. These domestic helpers experience negative attitudes, reduction of job content and retrenchment with concomitant financial repercussions. However, the participants in this study indicated that the attitude of employers' children towards them remain positive after diagnosis. In terms of the way in which they construct their experience around emotion, results indicate that they experience complex emotions including shock, uncertainty, loneliness, unworthiness, guilt, rejection, concern, anger, shamefulness and depression. Yet, they also present high levels of acceptance and spiritual growth. In terms of needs, they indicate the need for HIV-friendly workplaces and medical care. They specifically desire employers to help care for their children when they pass away. A comprehensive appraisal of the research results points towards two key aspects: the lack of agency that is prevalent in this group of participants and the silences that is evident from their narratives. The narratives of the HIV-positive domestic helpers indicate that they easily negate agency of their lives to their employers and concomitantly that the lack of agency hampers their ability to retain a sense of worthiness and responsibility for their lives. The results from this study also ensconce silences in many guises. Silences were reflected: <ul> <li> through semantic values and linguistic nuances,</li> <li> regarding acts or omissions of employers,</li> <li> regarding communications,</li> <li> regarding needs and</li> <li> regarding reduction of job content</li> </ul> In rare instances, the construction of experiences of some participants confirmed the ability of HIV-positive domestic helpers to accept agency of their circumstances. In summary, HIV-positive domestic helpers in this study experienced a lack of agency, they report narratives of silences, but they also reflect elements of healing, growth and spiritual deepening when they construct their experiences of HIV&AIDS in their families of employment. Copyright 2004, University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria. Please cite as follows: Barnard, JP 2004, MIV-positiewe huiswerksters se konstruering van hul ervarings van MIV en VIGS binne die werkgewersgesin (Afrikaans), PhD thesis, University of Pretoria, Pretoria, viewed yymmdd < http://upetd.up.ac.za/thesis/available/etd-03112005-080007 / > / Thesis (PhD (Educational Psychology))--University of Pretoria, 2006. / Educational Psychology / unrestricted
64

'n Verkenning van opvoeders se mobilisering van bates ter ondersteuning van gemeenskapshantering van MIV/VIGS (Afrikaans)

Loots, Mathilda Christina 05 September 2005 (has links)
The purpose of this study was to empower educators to mobilise assets and resources within their community in order to enable the community to cope better with the daily difficulties associated with HIV/AIDS. The study was conducted to explore and describe the process of mobilising assets in a HIV/AIDS infected and affected rural community. The working assumption was that the mobilisation of community assets could support and enhance community-based coping with the HIV/AIDS pandemic. A qualitative approach was followed. Purposeful sampling was applied to select an information-rich case for in-depth study (instrumental case study design). The case was a primary school in the Nelson Mandela Metropole. Ten educators participated in the study. The study was theoretically founded on an asset-based approach, with the focus on community-based coping. An interpretavist approach was used to describe and interpret the process of asset mobilisation in coping with HIV/AIDS. A number of data selection strategies were implemented: focus groups in combination with workshops, visual data, observation and a reflective field journal. The ten educators who participated in the study were empowered to identify and mobilise assets and resources within their community and to continue with the facilitation process on their own. The educators identified three priority areas and succeeded in establishing a vegetable garden on the school premises, a support group and an information centre at school, for HIV/AIDS infected and affected members of the community. These initiatives resulted in the wider community being better equipped and empowered to cope with the daily difficulties associated with HIV/AIDS that are being experienced on emotional, spiritual, materialistic, social and knowledge levels. It is concluded that the community, the school and individuals were empowered with regard to effective coping strategies, more specifically in dealing with the challenges associated with HIV/AIDS. / Dissertation (MEd (Educational Psychology))--University of Pretoria, 2006. / Educational Psychology / unrestricted
65

An assessment tool for social workers to identify risk behaviour in foster children / Narina Bester

Bester, Narina January 2014 (has links)
Problem statement Due to HIV and AIDS impacting on communities, devastating consequences have been predicted. The number of orphans and vulnerable children (OVC) in need of care is escalating, causing social workers’ caseloads to become unmanageable. These OVC who lost their parents through death are suffering multiple losses due to being orphaned. The material, protection and affection needs have to be addressed in a holistic, eco-systematic, multidisciplinary team approach. In practice social workers tend to focus mainly on the material and protection needs of OVC due to high caseloads and staff turnover, neglecting their affection needs. Social workers need to work with foster parents and children in identifying potential risk factors that could lead to risk behaviour in foster children who have lost their parents through death. The researcher designed an assessment tool that could enable social workers in practice to do an effective risk assessment of OVC in foster care. Intervention could be planned accordingly by setting goals to address risk factors timeously in an attempt to prevent future problem behaviour in OVC placed in foster care. Aim To develop an assessment tool for social workers to identify risk behaviour in foster children who have experienced multiple losses such as the loss of one or both parents. Method A mixed methods design was used, specifically the sequential and explanatory design which involved collecting and analysing both qualitative and quantitative data. These obtained data were then connected and integrated. Results It was proved that a Risk assessment tool helped social workers to identify risk factors in a team effort between social workers, foster parents and children. Meeting the psychosocial needs of OVC placed in foster care more effectively is important in order to prevent the development of negative behaviour. / PhD (Social Work), North-West University, Potchefstroom Campus, 2015
66

An assessment tool for social workers to identify risk behaviour in foster children / Narina Bester

Bester, Narina January 2014 (has links)
Problem statement Due to HIV and AIDS impacting on communities, devastating consequences have been predicted. The number of orphans and vulnerable children (OVC) in need of care is escalating, causing social workers’ caseloads to become unmanageable. These OVC who lost their parents through death are suffering multiple losses due to being orphaned. The material, protection and affection needs have to be addressed in a holistic, eco-systematic, multidisciplinary team approach. In practice social workers tend to focus mainly on the material and protection needs of OVC due to high caseloads and staff turnover, neglecting their affection needs. Social workers need to work with foster parents and children in identifying potential risk factors that could lead to risk behaviour in foster children who have lost their parents through death. The researcher designed an assessment tool that could enable social workers in practice to do an effective risk assessment of OVC in foster care. Intervention could be planned accordingly by setting goals to address risk factors timeously in an attempt to prevent future problem behaviour in OVC placed in foster care. Aim To develop an assessment tool for social workers to identify risk behaviour in foster children who have experienced multiple losses such as the loss of one or both parents. Method A mixed methods design was used, specifically the sequential and explanatory design which involved collecting and analysing both qualitative and quantitative data. These obtained data were then connected and integrated. Results It was proved that a Risk assessment tool helped social workers to identify risk factors in a team effort between social workers, foster parents and children. Meeting the psychosocial needs of OVC placed in foster care more effectively is important in order to prevent the development of negative behaviour. / PhD (Social Work), North-West University, Potchefstroom Campus, 2015
67

Riglyne vir pleegouers by die bekendmaking van pediatriese MIV

Davin, Reda J. (Reda Johanna) 05 October 2011 (has links)
Afrikaans text / Die studie ondersoek die leemte aan teoreties gefundeerde riglyne om pleegouers in die bekendmakingsproses van hulle kind se MIV-positiewe status te ondersteun Die studie geskied binne die teoretiese raamwerk van ʼn intervensienavorsingsmodel. In die empiriese navorsing is die vrese en probleme van pleegouers by die bekendmakingsproses ondersoek. Daar is bevind dat hierdie vrese en probleme in ag geneem moet word in die beoogde riglyne. Die kognitiewe ontwikkeling van die kind is deur middel van ʼn literatuurstudie ondersoek om vas te stel watter kennis, denke en inligting die kind op verskillende ouderdomme begryp. Daar is bevind dat kinders wat MIV-positief is, moontlike agterstande ondervind en dat die riglyne gevolglik gebaseer moet word op die toenemende ontwikkeling van die kind, met begrip vir individuele ontwikkelingsverskille. Voorts is bevind dat pleegouers se eie gereedheid ʼn belangrike rol speel. Alhoewel die pleegouer die bekendmakingsproses self moet aanvoer en hanteer is dit belangrik dat die pleegouers deur ʼn interdissiplinêre span ondersteun en begelei sal word. / This study investigates the absence of theoretical grounded guidelines to support foster parents when disclosing paediatric HIV. The study was done within the theoretical framework of an intervention research model. The empirical research investigated the fears and problems experienced by foster parents during the disclosure process. It was found that these fears and problems should be taken into account when compiling guidelines. The child‟s cognitive development was researched by way of a literary study in order to determine what knowledge, thoughts and information the child is able to grasp at different ages. It was found that children who are HIV positive could possibly lag behind and that the guidelines should therefore be based on the accumulative development of the child, with consideration given to individual developmental differences. Furthermore, it was established that foster parents‟ own readiness plays an important role. For this reason the foster parents should be supported and guided by an interdisciplinary team, but that they themselves should take care and execute the process of disclosure. / Social Work / M. Diac. (Spelterapie)
68

Etude du métabolisme des phénylpropanoïdes; analyse de l'interaction de la caféoyl-coenzyme A 3-O-méthyltransférase (CCoAOMT) avec son substrat et caractérisation fonctionnelle d'une nouvelle acyltransférase, l'HydroxyCinnamoyl-CoA : shikimate/quinate hydroxycinnamoyl Transférase (HCT).

Hoffmann, Laurent 04 July 2003 (has links) (PDF)
Le métabolisme des phénylpropanoïdes est un métabolisme secondaire spécifique au règne végétal. Il conduit, à partir de la phénylalanine, à la synthèse d'une grande variété de substances telles que les anthocyanes, les isoflavonoïdes, les stilbènes, des esters d'acides hydroxycinnamiques, ou encore à la lignine. Ces métabolites secondaires interviennent dans la pigmentation florale ou encore la protection des tissus végétaux contre divers stress biotiques et abiotiques. Quant à la lignine, elle assure rigidité aux parois cellulaires végétales et imperméabilité aux tissus conducteurs. La lignine est un polymère tridimensionnel constitué de trois unités monomériques qui possèdent le même squelette carboné phénylpropane mais diffèrent par leur degré de méthoxylation et d'hydroxylation. Une partie de mon travail de thèse a consisté à étudier la relation structure/fonction de la caféoyl-coenzyme A O-méthyltransférase (CCoAOMT) de N. tabacum, responsable de l'introduction de la première des deux fonctions méthyles. Des études bioinformatiques couplées à des approches de biochimie et de mutagenèse dirigée, nous ont permis de modéliser l'interaction de la CCoAOMT avec son substrat, le caféoyl-CoA. Trois acides aminés du site actif ont notamment été identifiés comme intervenant dans la reconnaissance spécifique de la chaîne latérale de CoA. J'ai également caractérisé, chez N. tabacum, une nouvelle acyltransférase à activité HydroxyCinnamoyl-CoA : shikimate/quinate hydroxycinnamoyl Transférase (HCT) impliquée dans le métabolisme des phénylpropanoïdes. Nous avons montré que l'enzyme HCT recombinante synthétisait, in vitro, les substrats de l'hydroxylation en position 3 du noyau aromatique. De plus, la répression de l'expression du gène HCT par le «VIGS» conduit à un ralentissement de la croissance des plantes, à une perturbation importante du pool d'acide chlorogénique, ainsi qu'à une diminution de la quantité et à une modification de la composition de la lignine synthétisée.
69

Die rol wat die reg op toegang tot gesondheidsorgdienste speel in armoedevermindering in Suid–Afrika / Z. Strauss (Kruger)

Strauss, Zannelize January 2010 (has links)
Section 27(1)(a) of the Constitution of the Republic of South Africa, 1996, entrenches everyone's right of access to health care services. The purpose of this dissertation is to determine the manner in which this right must be interpreted and implemented in order to alleviate poverty to the optimal extent possible, in South Africa. As a point of departure, the relationship between poverty and health, as well as the theoretical basis of poverty, is addressed in terms of soft law. Thereafter, the theoretical basis of the right of access to health care service is analysed and explained from both an international and a South African perspective. This is followed by an investigation into international law. The manner in which the United Nations International Covenant on Economic, Social and Cultural Rights is interpreted and implemented and whether or not this contributes to poverty alleviation, is investigated. This is followed by an analysis of the right in terms of the Constitution and case law. Particular attention is paid to the manner in which the courts interpret the right of access to health care services. It is then determined whether the state is implementing the right in such a manner as to contribute to the optimal alleviation of poverty, in South Africa. Finally, a conclusion is reached and recommendations are made as to ways in which the right can be interpreted and implemented to reduce poverty to the optimal extent possible, in South Africa. / Thesis (LL.M.)--North-West University, Potchefstroom Campus, 2010.
70

Medicine prescribing patterns in HIV/AIDS and non HIV/AIDS children : a comparative study in the private health care sector of South Africa / Mocke, M.

Mocke, Martlie January 2010 (has links)
Background: According to the United Nations AIDS Reference Group (2010) and World Health Organization (2010:2), approximately 33 million people in the world had HIV/AIDS in 2009 of which 2.6 million were children. More than 30 million of these individuals resided in low– and middle–income countries. South–Africa had the highest prevalence of HIV/AIDS in the world with an estimated 5.2 million patients in 2009 (Statistics South Africa, 2010:2). Although the prevalence of human immunodeficiency virus (HIV) infection among children is reported to be high, little is known about other medication administrated concomitantly with their antiretroviral drugs. Objective: The general objective of this study was to investigate possible changes in the medicine prescribing patterns of HIV/AIDS and non–HIV/AIDS children. Methods: A quantitative, retrospective drug utilisation review was performed utilising medicine claims data of a South African pharmacy benefit management company. Data for a four–year period (Jan 1, 2005 to Dec 31, 2008) were analysed. The study population consisted of all children <=12 years divided into those receiving ARVs (designated HIV positive) and those without (designated HIV negative). Descriptive statistics such as average mean, standard deviation, t–test, d–values, and two way frequency tables were used to describe the results. Data were analysed using the Statistical Analysis System ® SAS 9.1 ® programme. Results: The study population (children <= 12 years) represented 16.2% (n = 197 323) of the total population in 2005, 15.4% (n = 193 346) in 2006, 15.6% (n = 142 049) in 2007 and 13.3% (n = 98 939) in 2008. Children with HIV/AIDS represented 0.2% (n = 197 323) of the study population in 2005 and increased to 0.4% (n = 98 939) in 2008, whereas the percentage of children without HIV/AIDS decreased from 99.8% (n = 197 323) in 2005 to 99.6% (n = 98 939) in 2008. The total number of HIV/AIDS children that also received other medication concomitantly with their ARVs increased from 96.5% (n = 402) in 2005 to 97.2% (n = 427) in 2008. Males with HIV/AIDS who used other medication represented 52.6% (n = 388) in 2005 and increased to 53.3% in 2008 while female HIV/AIDS patients represented 47.4% in 2005 and decreased to 46.7% in 2008. Prescriptions containing three ARV items represented 69.5% (n = 2 969) of the total number of prescriptions received by HIV/AIDS patients in 2005 and decreased to 67.7% in 2008. The combination of lamivudine, nevirapine and stavudine were the three products that appeared most frequently on prescriptions for HIV/AIDS children in the age group 0 <= 1 years and 1 <= 5 years from 2005 to 2008. In the age group 5 <= 12 years the combination most frequently prescribed was lamivudine, nevirapine and zidovudine. HIV positive children received 6.2 ± 4.62 prescriptions for other medication (non–ARVs) per year during 2005 compared to HIV negative children with 3.9 ± 3.71 (p < 0.0001, d = 0.5). In 2008 HIV positive children received 6.4 ± 5.02 prescriptions per year compared to HIV negative patients who received 4.36 ± 4.05 prescriptions (p < 0.0001, d = 0.5) in 2008. HIV negative children received more central nervous system items, endocrine items and autacoids than HIV positive children, whereas HIV positive children received more respiratory system agents, dermatological, ear, nose throat and antimicrobials items. Conclusion: The study showed that HIV positive children received significantly more prescriptions for other medication per year compared to their HIV negative counterparts. The top pharmacological groups mostly prescribed to both groups were respiratory agents, antimicrobials, analgesics, dermatological and ear, nose and throat items. / Thesis (M.Pharm. (Pharmacy Practice))--North-West University, Potchefstroom Campus, 2012.

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