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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.
51

Recherche de composés à activité antiplasmodiale à partir de la biodiversité malgache / Search for antiplasmodial compounds from the malagasy biodiversity

Beniddir, Ahmed-mehdi 31 October 2012 (has links)
Dans le cadre de la recherche de nouveaux composés à activité antiplasmodiale, deux plantes de Madagascar ont été étudiées : Pyrostria major (Rubiaceae) et Gonioma malagasy (Apocynaceae). Leurs extraits acétate d’éthyle et alcaloïdique ont montré une activité antiplasmodiale significative vis-à-vis de la souche chloroquino-résistante FcB1 lors d’un criblage préliminaire. L’étude phytochimique des feuilles de P. major a conduit à l’isolement du β sitostérol ainsi que de huit nouveaux diarylheptanoïdes glycosylés, décrits pour la première fois dans une plante appartenant à la famille des Rubiaceae. L’activité antiplasmodiale de l’extrait AcOEt des feuilles est probablement due à la présence du β sitostérol. Cette activité serait due à l’effet stomatocytogénique provoqué par cette famille de composés. L’utilisation de l’"Exciton chirality" a permis de déterminer la configuration absolue des diarylheptanoïdes glycosylés isolés. Cette étude structurale nous a permis d’obtenir d’une part, deux composés antiplasmodiaux sélectifs et non cytotoxiques et d’autre part, un composé antileishmanien et un autre antitrypanosomal. L’étude de l’extrait alcaloïdique de G. malagasy a conduit à l’isolement d’une nouvelle série chimique, "les goniomedines". Ces dernières sont caractérisées par un squelette bisindolique constitué de deux monomères dihydroindoliques reliés par une unité dihydropyrane. Une étude configurationnelle basée sur le calcul théorique de spectres de dichroïsme circulaire ainsi que sur des considérations biogénétiques, a permis la détermination de leur configuration absolue. Parmi ces composés, un seul a montré une activité antiplasmodiale significative. / As part of the search for new compounds with antiplasmodial activity, two malagasy plants were studied: Pyrostria major (Rubiaceae) and Gonioma malagasy (Apocynaceae). The Ethyl acetate and alkaloidic extracts showed significant antiplasmodial activity against the chloroquine-resistant strain FcB1 during a preliminary screening. The phytochemical study of the leaves of P. major has led to the isolation of β-sitosterol together with eight new diarylheptanoid glucoside, described for the first time in a plant belonging to the Rubiaceae family. The antiplasmodial activity of the EtOAc extract of the leaves is probably due to the presence of β-sitosterol. This activity is due to the stomatocytogenic effect caused by this family of compound. The use of the "exciton chirality" has determined the absolute configuration of the natural diarylheptanoid glucoside. This structural study allowed us to obtain, two selective antiplasmodial and non-cytotoxic compounds, as well as potential antileishmanial and antitrypanosomal compounds. The study of the alkaloidic extract of G. malagasy led to the isolation of a novel chemical series, "The goniomedines." They are characterized by a bisindole backbone consisting of two monomers connected by a dihydropyran unit. Their absolute configurations were deduced following the comparison of experimental and theoretically calculated ECD spectra and through biogenetic considerations. Among these compounds, only one showed a significant antiplasmodial activity.
52

Factors affecting the implementation of inclusive education policy: A case study in one province in South Africa

Stofile, Sindiswa Yvonne January 2008 (has links)
Philosophiae Doctor - PhD / After the democratic elections of 1994, the South African government embarked on radical reforms to the apartheid education system, which included the development of a policy that is committed to human rights and social justice. The inclusive education policy, entitled: Education White Paper 6: Special Needs Education: Building an Inclusive Education and Training System (Department of Education, 2001) was released in July 2001. This inclusive education policy brought with it the prospect of changing the structures that promoted exclusionary and discriminatory practices in the education system. While the inclusive education framework is characterised by explicit policy directives, well-defined outcomes and a firm commitment to human rights and social justice, there is a growing realisation that a considerable gap exists between this framework and its effective implementation. The main aim of this study was to understand the factors that facilitate or constrain the implementation of inclusive education in the South African context. These factors were explored through a qualitative case study. A documentary analysis, as well as unstructured and semi-structured interviews was used to collect the data within the context of the research aims, questions, and a framework of categories, drawn from relevant literature, was used to analyse the data. The first major finding of this study was that the implementation of inclusive education policy in South Africa has been facilitated by the school communities' beliefs, values and norms relating to the inclusion of learners with disabilities. The second major fmding of this study is that the designers of the inclusive education policy underestimated the deep-seated socio-economic factors that inhibit effective learning in certain contexts. Poverty was identified as a major constraining factor in the study, followed by the complexities of the National Curriculum Statement, a lack of capacity to implement the policy, lack of support for policy implementation, and the limitations of the Education White Paper 6 itself. Given the facilitating and constraining factors emerging from this study, the recommendations made have been based on the assumption that the implementation of inclusive education policy is a worthwhile endeavour. These recommendations are proposed within three broad areas, namely policy implementation, inclusive education policy, and inclusive education practice. Of these recommendations the following are critical: • The Department of Education should develop differentiated inclusive education guidelines that address inclusion of learners in poverty stricken contexts. • The Department of Education, in conjunction with schools, should create formal and informal communication channels through which stakeholders can raise their views and concerns about the policy of inclusive education and how it should be implemented. • The Department of Education should take full responsibility for the advocacy, implementation, monitoring and evaluation of inclusive education policy, rather than relying on the services of independent providers. • The Department of Education should address the complexities that prevent districts and schools from establishing support structures.
53

Learning experiences of inner city early childhood development managers who participated in an ECD forum: a social work perspective

McLean, Barbara Anne 05 1900 (has links)
Early childhood development is one of the critical services to support the development of young children from conception to age six. Children raised in vulnerable inner cities, with limited access to quality, well-resourced ECD services, are at risk of perpetuating cycles of disadvantage and exclusion. Even though ECD centres exist in abundance in the inner city of Durban, eThekwini Municipality, KwaZulu-Natal, managers of ECD centres face challenges such as meeting rigorous registration norms and standards, a lack of finances, resources, trained staff and socio-economic factors which affect the wellbeing of children. Using a qualitative approach, this study communicates the role played by the Inner City ECD Forum in the learning experiences of seven ECD managers through their participation in inter-sectoral stakeholder interventions and capacity building trainings. It further outlines the benefits of networking and collective support. Based on the findings, recommendations for practice, policy and further research are made. / School of Social Sciences / M.A. (Social Work)
54

Thermal ALD of Cu via Reduction of CuxO films for the Advanced Metallization in Spintronic and ULSI Interconnect Systems

Mueller, Steve, Waechtler, Thomas, Hofmann, Lutz, Tuchscherer, Andre, Mothes, Robert, Gordan, Ovidiu, Lehmann, Daniel, Haidu, Francisc, Ogiewa, Marcel, Gerlich, Lukas, Ding, Shao-Feng, Schulz, Stefan E., Gessner, Thomas, Lang, Heinrich, Zahn, Dietrich R.T., Qu, Xin-Ping 21 February 2012 (has links) (PDF)
In this work, an approach for copper atomic layer deposition (ALD) via reduction of CuxO films was investigated regarding applications in ULSI interconnects, like Cu seed layers directly grown on diffusion barriers (e. g. TaN) or possible liner materials (e. g. Ru or Ni) as well as non-ferromagnetic spacer layers between ferromagnetic films in GMR sensor elements, like Ni or Co. The thermal CuxO ALD process is based on the Cu (I) β-diketonate precursor [(nBu3P)2Cu(acac)] and a mixture of water vapor and oxygen ("wet O2") as co-reactant at temperatures between 100 and 130 °C. Highly efficient conversions of the CuxO to metallic Cu films are realized by a vapor phase treatment with formic acid (HCOOH), especially on Ru substrates. Electrochemical deposition (ECD) experiments on Cu ALD seed / Ru liner stacks in typical interconnect patterns are showing nearly perfectly filling behavior. For improving the HCOOH reduction on arbitrary substrates, a catalytic amount of Ru was successful introduced into the CuxO films during the ALD with a precursor mixture of the Cu (I) β-diketonate and an organometallic Ru precursor. Furthermore, molecular and atomic hydrogen were studied as promising alternative reducing agents.
55

ALD-grown seed layers for electrochemical copper deposition integrated with different diffusion barrier systems

Waechtler, Thomas, Ding, Shao-Feng, Hofmann, Lutz, Mothes, Robert, Xie, Qi, Oswald, Steffen, Detavernier, Christophe, Schulz, Stefan E., Qu, Xin-Ping, Lang, Heinrich, Gessner, Thomas 18 May 2011 (has links) (PDF)
The deposition of Cu seed layers for electrochemical Cu deposition (ECD) via atomic layer deposition (ALD) of copper oxide and subsequent thermal reduction at temperatures between 110 and 120°C was studied on different diffusion barrier systems. While optimization of the process is required on TaN with respect to reduction and plating, promising results were obtained on blanket PVD Ru. The plating results on layers of ALD Cu with underlying Ru even outperformed the ones achieved on PVD Cu seed layers with respect to morphology and resistivity. Applying the processes to via and line patterns gave similar results, suggesting that a combination of ALD Cu with PVD or ALD-grown Ru could significantly improve the ECD Cu growth.
56

ALD-grown seed layers for electrochemical copper deposition integrated with different diffusion barrier systems

Waechtler, Thomas, Ding, Shao-Feng, Hofmann, Lutz, Mothes, Robert, Xie, Qi, Oswald, Steffen, Detavernier, Christophe, Schulz, Stefan E., Qu, Xin-Ping, Lang, Heinrich, Gessner, Thomas January 2011 (has links)
The deposition of Cu seed layers for electrochemical Cu deposition (ECD) via atomic layer deposition (ALD) of copper oxide and subsequent thermal reduction at temperatures between 110 and 120°C was studied on different diffusion barrier systems. While optimization of the process is required on TaN with respect to reduction and plating, promising results were obtained on blanket PVD Ru. The plating results on layers of ALD Cu with underlying Ru even outperformed the ones achieved on PVD Cu seed layers with respect to morphology and resistivity. Applying the processes to via and line patterns gave similar results, suggesting that a combination of ALD Cu with PVD or ALD-grown Ru could significantly improve the ECD Cu growth.
57

Thermal ALD of Cu via Reduction of CuxO films for the Advanced Metallization in Spintronic and ULSI Interconnect Systems

Mueller, Steve, Waechtler, Thomas, Hofmann, Lutz, Tuchscherer, Andre, Mothes, Robert, Gordan, Ovidiu, Lehmann, Daniel, Haidu, Francisc, Ogiewa, Marcel, Gerlich, Lukas, Ding, Shao-Feng, Schulz, Stefan E., Gessner, Thomas, Lang, Heinrich, Zahn, Dietrich R.T., Qu, Xin-Ping January 2011 (has links)
In this work, an approach for copper atomic layer deposition (ALD) via reduction of CuxO films was investigated regarding applications in ULSI interconnects, like Cu seed layers directly grown on diffusion barriers (e. g. TaN) or possible liner materials (e. g. Ru or Ni) as well as non-ferromagnetic spacer layers between ferromagnetic films in GMR sensor elements, like Ni or Co. The thermal CuxO ALD process is based on the Cu (I) β-diketonate precursor [(nBu3P)2Cu(acac)] and a mixture of water vapor and oxygen ("wet O2") as co-reactant at temperatures between 100 and 130 °C. Highly efficient conversions of the CuxO to metallic Cu films are realized by a vapor phase treatment with formic acid (HCOOH), especially on Ru substrates. Electrochemical deposition (ECD) experiments on Cu ALD seed / Ru liner stacks in typical interconnect patterns are showing nearly perfectly filling behavior. For improving the HCOOH reduction on arbitrary substrates, a catalytic amount of Ru was successful introduced into the CuxO films during the ALD with a precursor mixture of the Cu (I) β-diketonate and an organometallic Ru precursor. Furthermore, molecular and atomic hydrogen were studied as promising alternative reducing agents.
58

A plan-do-check-act framework for WEEE and RoHS : a model for implementing WEEE and RoHS by integrating eco-design factors and activities into business operation and strategy.

El-Gomla, Randa A.M. January 2011 (has links)
Eco-design is relatively new and fast growing field of research due to its vital importance to the manufacturing industry and its related environmental issues such as reducing waste, and CO2 emission. A major EU programme relating to the environment is the waste of Electrical and Electronic Equipment (WEEE) directive. The (WEEE) directive specifies ten categories and a voltage range which is up to 1.000 volts AC or 1.500volts DC. The developed framework came for the implementation of Eco-design principles that helps to take into account the adaption of the (WEEE) directive and the restriction of hazard substances (RoHS) used in electrical and electronic equipments. As a result of identify gaps and needs such as a lack of a comprehensive Eco-design framework and the need to integrate it to the normal business operation. In this research the PDCA framework for Eco-design and WEEE directive will be discussed. The framework will encompass all of the Eco-design¿s implementation and integration factors and activities such as WEEE and RoHS directives, Eco-design management, Environmental legislations, Eco-design tools and considerations. The literature review covers the topic of Eco-design¿s related issues, and WEEE and RoHS directives rules. Based on comprehensive questionnaire survey of Eco-design, WEEE and RoHS issues and activities among a sample of environmentally aware companies, statistical analysis is carried out using SPSS software. Then the findings of the survey triangulated with the findings of the literature review formed the basis of the design and implementation plan of the proposed framework
59

Fostering self-regulation through positive discipline during free play in early childhood education

Msipha, Zenzile 10 June 2021 (has links)
Abstract in English, Afrikaans and Zulu / The fostering of self-regulation is of great importance in the Early Childhood Development (ECD) phase, because it leads to future self-discipline. The aim of the study was to understand the participants’ ways of fostering self-regulation during free play in three primary schools in Zimbabwe. The theoretical frameworks of the study, namely positive psychology and Deci and Ryan’s Self-Determination Theory (SDT), as well as the Basic Psychological Needs Theory (BPNT), regarded the learners’ support for autonomy, competence and relatedness as key characteristics of positive discipline that support the development of self-regulation. Benner’s interpretive phenomenology method was used with the aim of describing and interpreting participants’ experiences of the phenomenon under study. The social constructivism paradigm underpinned the study and the approach was qualitative. Data collection and analysis were guided by Benner’s interpretive phenomenological method. A paradigm case, themes and exemplars were used in data presentation, discussion and interpretation. Findings showed that free-play activities consisted of, for instance, socio-dramatic play, indoor play in play corners and outdoor play. The common practices used by the participants to foster self-regulation through positive discipline were co-regulation, positive reinforcement, time-out and logical consequences. Teachers and learners often perceived the teachers’ use of time-out and logical consequences as punishment rather than positive discipline, because of the rigidity of its application without considering psychosocial needs. The findings, however, were consistent with an understanding of fostering self-regulation through positive discipline during free play by nurturing the learners’ psychological needs for autonomy, competence and relatedness, as well as mindfulness. Research proposed mindfulness as a possible fourth basic psychological need. In line with the Sustainable Development Goals (SDGs) for achieving a better and sustainable future for all people by 2030, participants perceived the fostering of self-regulation through positive discipline as part of gender education for eradicating gender-based violence and to foster resilience. / Selfregulering moet in die vroeë kinderjare reeds by klein kinders gekweek word sodat hulle later in die lewe in staat sal wees om selfdissipline aan die dag te lê. Die doel van hierdie studie was om vas te stel hoe die deelnemers by drie laerskole in Zimbabwe gedurende vrye spel selfregulering by leerders gekweek het. Die drie teoretiese raamwerke waarop hierdie studie berus, is die positiewe sielkunde, Deci en Ryan se selfbeskikkingsteorie (SBT) en die teorie van basiese psigososiale behoeftes (TBSB). Hiervolgens is die bevrediging van kinders se behoefte aan outonomie, bedrewenheid (‘competence’) en verhoudings (‘relatedness’) voorvereistes vir die positiewe dissiplinering waarmee selfregulering by hulle gekweek word. Benner se metode van interpretatiewe fenomenologie is gevolg om deelnemers se belewing van die fenomeen te beskryf en te vertolk. Die sosiale konstruktivisme het die grondslag van hierdie studie gevorm, en die benadering was kwalitatief. Data is volgens Benner se metode van interpretatiewe fenomenologie ingewin en ontleed. ʼn Paradigmageval, temas en voorbeelde (‘exemplars’) is in die aanbieding, bespreking en interpretasie van data gebruik. Volgens die bevindings het vryespelaktiwiteite bestaan uit onder meer sosiaal-dramatiese spel, binnenshuise spel in speelhoekies, en buitelugspel. Die praktyke waarvolgens deelnemers selfregulering deur positiewe dissiplinering gekweek het, was onderlinge regulering, positiewe versterking, afkoeltyd en logiese gevolge. Onderwysers en leerders het afkoeltyd en logiese gevolge nie as positiewe dissiplinering nie, maar eerder as straf belewe aangesien dit streng toegepas word en nie met die kind se psigososiale behoeftes rekening hou nie. Die bevindings strook egter met ons siening van die kweek van selfregulering deur positiewe dissiplinering tydens vrye spel deur leerders se psigososiale behoefte aan outonomie, bedrewenheid (‘comptetence’), verhoudings (‘relatedness’) en bewustheid (‘mindfulness’) te bevredig. Navorsers stel bewustheid (‘mindfulness’) as ʼn vierde basiese psigososiale behoefte voor. In ooreenstemming met die Doelwitte vir Volhoubare Ontwikkeling (DVO’s) vir ʼn beter en volhoubare toekoms vir alle mense teen 2030, het deelnemers gevind dat die kweek van selfregulering deur positiewe dissiplinering deel uitmaak van genderopvoeding as teenvoeter vir geslagsgeweld, en vindingrykheid aanwakker. / Ukukhuthaza ukuzilawula kubaluleke kakhulu esigabeni sokuThuthukiswa Kwabantwana Abasebancane (i-ECD phase), ngoba kuholela ekuzikhalimeni esikhathini esizayo. Inhloso yalolu cwaningo bekuwukuqonda izindlela zababambiqhaza zokukhuthaza ukuzilawula ngesikhathi sokudlala ngokukhululeka ezikoleni ezintathu zamabanga aphansi eZimbabwe. Izinhlaka zombono wezinzululwazi zalolu cwaningo, ezaziwa ngokuthi okuhle kwengqondo kanye noMbono Wenzululwazi kaDeci noRyan Wokuzimisela (i-SDT), kanye noMbono Wenzululwazi Wezidingo Eziyisisekelo Zokuphathelene Nenggqondo (i-BPNT), zithathe ukwesekwa kwabafundi njengokuzimele, ikhono kanye nokuhlobana njengezimpawu ezisemqoka zokukwazi ukuzikhalima okuhle okusekela ukuthuthukiswa kokuzilawula. Kusetshenziswe indlela kaBenner yokuhumusha okwenzekile ngenhloso yokuchaza nokuhumusha okwenzeke kubabambiqhaza kulokho okufundwa ngako. Inqubo yokwakhiwa kwezenhlalakahle iyona esekele ucwaningo kanti futhi indlela yokwenza ibibheka amaqiniso. Ukuqoqwa kwemininingo nokuhlaziywa bekuncike endleleni kaBenner yokuhumusha okwenzekile. Kwasetshenziswa izimo semiqondo, izingqikithi kanye nezibonelo ukwethula imininingo, izingxoxo nokuhumusha. Okutholakele kukhombisile ukuthi ukudlala ngokukhululeka kubandakanya, ngokwesibonelo, ukudlala ngokulingisa ezenhlalo, ukudlala endlini emakhoneni okudlala kanye nokudlala ngaphandle. Imikhuba ejwayelekile esetshenziswa ngababambiqhaza ukukhuthaza ukuzilawula ngokusebenzisa ukukhalima okukahle kwakungukulawula ngokubambisana, ukukhuthaza okuhle, ukuqedwa komdlalo kanye nemiphumela eyenza umqondo. Othisha nabafundi babevame ukubona ukuqedwa komdlalo nemiphumela eyenza umqondo njengento esetshenziswa ngothisha njengesijeziso kunokukhalima okuhle, ngenxa yobukhuni bokusetshenziswa kwako ngaphandle kokubheka izidingo zomqondo. Okutholakele, nokho, bekuhambisana nokuqonda kokukhuthaza ukuzilawula ngokukhalima okukahle ngesikhathi sokudlala ngokukhululeka ngokunakekela izidingo zabafundi zokuphathelene nengqondo ekuzimeleni, ikhono kanye nokuhlobana, kanye nokuqaphela izinto. Ucwaningo luhlongoze ukuqaphela izinto njengesidingo sesine esiyisisekelo kokuphathelene nengqondo. Ngokuhambisanayo neziNjongo Zokuthuthukiswa Okusinokusimama (ama-SDG) ukuze kufezeke ikusasa elingcono nelinokusimama kubantu bonke ngonyaka ka- 2030, ababambiqhaza babona ukukhuthaza ukuzilawula ngokuzikhalima okukahle njengengxenye yemfundo yobulili ukuze kuncishiswe udlame oluncike ebulilini futhi kukhuthazwe ukuqina. / Psychology of Education / D. Ed. (Psychology of Education)
60

Parents' role in governance: the case of early childhood development centres in Mabopane

Mbele, Kgoto Jan 10 1900 (has links)
Good governance occupies a centre stage in the development discourse. Since there are currently no guidelines on the practice of good governance for ECD centres, this qualitative study followed the exploratory research approach and employed the case study research design to gain insight into how ECD centres in Mabopane practiced good governance concerning the roles played by parents in decision-making and accountability. The study used the Social Capital and Stakeholder theoretical frameworks to contextualise the investigation and employed eclectic methodological approaches involving triangulated sampling techniques, data collection methods and tools as well as data sources to generate data. The data were analysed using thematic content analysis and it was found amongst others that there were weaknesses in the governance practices within the ECD centres regarding parents’ roles in decision-making and accountability. The study recommended, amongst others, for concerted efforts involving all stakeholders to address those flaws. / Development Studies / M.A. (Development Studies)

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