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Nuclear level densities (NLDs) and gamma -ray strength functions (GSFs) of 120,124Sn have been extracted with the Oslo method from proton-gamma coincidences in the (p, p'gamma ) reaction. The functional forms of the GSFs and NLDs have been further constrained with the Shape method by studying primary gamma -transitions to the ground and first excited states. The NLDs demonstrate good agreement with the NLDs of 116,118,122Sn isotopes measured previously. Moreover, the extracted partial NLD of 1- levels in 124Sn is shown to be in fair agreement with those deduced from spectra of relativistic Coulomb excitation in forward-angle inelastic proton scattering. The experimental NLDs have been applied to estimate the magnitude of the Porter-Thomas (PT) fluctuations. Within the PT fluctuations, we conclude that the GSFs for both isotopes can be considered to be independent of initial and final excitation energies, in accordance with the generalized Brink-Axel hypothesis. Particularly large fluctuations observed in the Shape-method GSFs present a considerable contribution to the uncertainty of the method and may be one of the reasons for deviations from the Oslo-method strength at low gamma -ray energies and low values of the NLD (below eta 1 x 103-2 x 103 MeV-1).

We report on spectroscopic information and lifetime measurements of even-even neutron-rich Te isotopes. Excited states were populated in fast-neutron induced fission of U-238 at the ALTO facility of IJCLab with the LICORNE neutron source and detected using the hybrid.-ball spectrometer. We provide first results on lifetimes of the 6(1)(+) state in Te-136 and the (6(1)(+)), (4(1)(+)), and (2(1)(+)) states in Te-138 and discuss the results in the context of large-scale shell-model calculations. The level schemes of Te-136 and Te-138 are revised in terms of lifetimes of their 2(1)(+), 4(1)(+) states and updated information on the (4(2)(+)) state in Te-136 is presented. In addition, previously reported data on spectroscopy and lifetimes in Te-134 are reexamined. This work provides new insights into the evolution of collectivity for Te isotopes with N = 82, 84, 86.

We report on spectroscopic information and lifetime measurements in the neutron-rich I-135,I-137,I-139 isotopes. This is the first lifetime data on iodine isotopes beyond N = 82. Excited states were populated in fast neutron-induced fission of U-238 at the ALTO facility of IJCLab with the LICORNE neutron source and detected using the hybrid nu-ball spectrometer. The level schemes of the I-135,I-137,I-139 isotopes are revised in terms of excited states with up to maximum spin-parity of (33/2(+)), populated for the first time in fast neutron-induced fission. We provide first results on the lifetimes of the (9/2(1)(+)) and (13/2(1)(+)) states in I-137 and I-139, and the (17/2(1)(+)) state in 137I. In addition, we give upper lifetime limits for the (11/2(1)(+)) states in I135-139, the (15/2(1)(+)) state in I-137, the (17/2(1)(+)) state in I-139, and reexamine the (29/2(1)(+)) state in I-137. The isomeric data in I-13(5) are reinvestigated, such as the previously known (15/2(1)(+)) and (23/21) isomers with T-1/2 of 1.64(14) and 4.6(7) ns, respectively, as obtained in this work. The new spectroscopic information is compared to that from spontaneous or thermal-neutron induced fission and discussed in the context of large scale shell-model (LSSM) calculations for the region beyond Sn-132, indicating the behavior of collectivity for the three valence-proton iodine chain with N = 82, 84, 86.

The validity of the Brink-Axel hypothesis, which is especially important for numerous astrophysical calculations, is addressed for 116,120,124Sn below the neutron separation energy by means of three independent experimental methods. The gamma-ray strength functions (GSFs) extracted from primary gamma-decay spectra following charged-particle reactions with the Oslo method and with the shape method demonstrate excellent agreement with those deduced from forward-angle inelastic proton scattering at relativistic beam energies. In addition, the GSFs are shown to be independent of excitation energies and spins of the initial and final states. The results provide a critical test of the generalized Brink-Axel hypothesis in heavy nuclei, demonstrating its applicability in the energy region of the pygmy dipole resonance.

Excited states in the neutron-rich Se-85 nucleus have been studied using for the first time a fast neutron-induced fission of Th-232. The experiment was performed at the ALTO facility of the IPN Orsay. Coupling of the LICORNE directional neutron source with the nu-ball high-resolution gamma-ray spectrometer provided unique access to high-spin states in neutron-rich fission fragments from the Th-232(n,f) reaction. A preliminary level scheme of Se-85 was established by the analysis of prompt gamma-gamma-gamma coincidences. Identification of the all known yrast states in Se-85 is the first step towards studies of more neutron-rich Se isotopes.

Prompt and delayed gamma-ray spectroscopy of the neutron-rich Kr-94 was performed, as part of the fission campaign at the ALTO facility of the IPN Orsay, using the fast-neutron-induced fission reaction U-238(n, f) in combination with the nu-Ball array, a novel hybrid gamma spectrometer for energy and lifetime measurements. Several new yrast and nonyrast transitions were observed for the first time, extending the previously known level scheme. Additionally, we report on the observation of a new short-lived isomer at 3444 keV with a half-life of 32(3) ns. The analysis of the Nilsson orbitals obtained from Gogny cranked Hartree-Fock-Bogoliubov calculations suggests a (9(-)) spin and an oblate deformation for this isomer corresponding to a two-quasineutron state, indicating an isomeric structure very similar to that of the neighboring isotones Sr-96 and Se-92.

English: It is a big challenge to present Jesus through the impact of media programs to Muslims in general and Hausa Sunni Muslims of West Africa in particular. The goal of this project is to design a strategy for using media in the cross-cultural context to accomplish mission among Hausa Sunni Muslims of West Africa. The dissertation presents an analysis of mission challenges on the reaction of Muslims when they hear the gospel message in their context. This analysis focuses firstly on the premise that mission is from God. God as first missionary reached out to people in the garden and later to them who believe in Him and accept His plan through ages, and then to share this initiative. The study traces the development of that mission from creation to the present time. It shows that through history each people group needs a special strategy in a cross-cultural context to accept and adapt the gospel message in their life without yielding to syncretism. The project examines, secondly, the history of Sunni Muslims from the foundation of the religion to the present time, as well as their key doctrines and worldview. It also establishes some determinant factors, as culture and worldview, for an effective communication, that can influence positively the conversion of Sunni to the true gospel. Historical, social context and cultural analyses of Hausa Sunni Muslims were then undertaken and the influence of media is ascertained in the project. After exploring the contextual and audience analysis of Hausa Sunni Muslims, this study suggests that a bridge be built by using the Qur’an, especially the first chapter called Al fatiha (opening), when presenting the message. This strategy can break many existing barriers and can provide opportunities to facilitate the gospel penetration and expansion among this people group. The result of this study can be used by any church member who has the desire to preach the Gospel through media among Hausa Sunni Muslims or wherever it can be u, Afrikaans: Dit is ‘n groot uitdaging om Jesus deur middel van die media aan Moslems in die algemeen en veral Hausa Sunni Moslems in Wes-Afrika te verkondig. Die doel van hierdie projek is om ‘n strategie vir die gebruik van die media in kruis-kulturele konteks te ontwerp om Hausa Sunni Moslems in Wes-Afrika met die sending te bereik. Hierdie proefskrif bied ‘n ontleding van sendinguitdagings wat Moslems bied wanneer hulle die Evangelie binne hulle konteks hoor. Ten eerste word beklemtoon dat sending uit God is. God as eerste Sendeling het na die mense in die tuin uitgereik en later ook na hulle wat in Hom glo en sy plan deur al die eeue aanvaar het en dan deel in sy inisiatiewe. Die ontwikkeling van sending van die skepping af tot die huidige tyd word nagespeur. Dit is duidelik dat elke bevolkingsgroep ‘n eie unieke strategie nodig het binne die kruis-kulturele konteks om die Evangelie in hulle lewe te aanvaar sonder om aan sinkretisme skuldig te wees. Verder word die geskiedenis van Sunni Moslems van die oorsprong van hulle godsdiens tot die huidige tyd ondersoek en word ook hulle geloofsoortuigings en wêreldbeskouing ontleed. Dit lê ook sekere vaste beginsels soos kultuur en wêreldbeskouing neer vir effektiewe kommunikasie wat tot die bekering van Sunni Moslems tot die ware evangelie kan lei. Die historiese, sosiale konteks en kulturele analise van Hausa Sunni Moslems word dan onderneem en die invloed van die media word vasgestel. Nadat die konteks en die toehoorders se uitgangspunte vasgelê is, word aanbeveel dat Hausa Sunni Moslems deur middel van ‘n brug wat met die Qur’an gebou word, veral die eerste hoofstuk, naamlik die Al fatiha (opening), wanneer die boodskap gebring word, bereik word. Hierdie strategie kan baie hindernisse oorkom en kan ook geleenthede bied om die Evangelie oor te dra om die mense te bereik en onder die mense toe te en neem. Die historiese, sosiale konteks en kulturele analise van Hausa Sunni Moslems word dan onderneem en die invloed van

English: The aims of this study are to, by means of a review of the literature and empirical investigation: • gain an understanding of the complexity and the extent to which teachers experience job satisfaction, work values and work-related stress, with particular reference to secondary schools in the Eastern Free State; and • measure the levels of stress among a group of secondary school teachers, as well as to determine the effect of biographical and organisational factors on their levels of stress. Furthermore, the aim was to look at relations in terms of how the job satisfaction and work values (teachers' needs) of these teachers are affected by work-related stress. It became very clear from the literature review that the impact of stress is experienced at all levels of society (Van Zyl & Pietersen 1999:74), from individuals to national level. In the Sunday Times (August 1999) it is indicated that South Africa is a very stressed society and that support is becoming harder to find, as familial networks are not strong enough. A very clear fact is that, without support, stress spills over into different relationships and environments. In this study it was furthermore concluded that the teaching profession also has the potential of being stressful and affecting the working environment. It was found that a lack of effective stress management results in important decrements in well-being, as well as dissatisfaction among teachers and an inability to perform up to standard (compare 6.1). The literature survey also revealed that both satisfaction and performance are connected to rewards (Steyn & Van Wyk 1999:37): • Rewards impact more directly on the cause of satisfaction than performance. • Rewards levelled on ongoing performance cause subsequent performance. Therefore this research evidence confirms the fact that it is extremely important for supervisors or school management to show appreciation and recognition of the work which is done well by teachers. Lynn (1998:46, Afrikaans: Die doelstellings van hierdie studie is die volgende: • Om In denkbeeld te vorm van die kompleksiteit en die mate waarin onderwysers werksbevrediging, werkswaardes en werksverwante stres ervaar met spesifieke verwysing na sekondêre skole in die Oos-Vrystaat. • Om die stresvlakke van In groep sekondêreskool-onderwêsers te meet, asook om die effek van biografiese en organisatoriese faktore op hul stresvlakke te bepaal. Verder was die doelom verhoudinge in oënskou te neem in terme van hoe die werksbevrediging en werkswaardes (onderwysers se behoeftes) van hierdie onderwysers beïnvloed word deur werksverwante stres. Bogenoemde doelstellings is verwesenlik deur middel van In oorsig van die literatuur en In empiriese ondersoek. Uit die literatuurstudie het dit baie duidelik geblyk dat die impak van stres op alle vlakke van die samelewing ondervind word (Van Zyl & Pietersen 1999:74), vanaf individue tot op nasionale vlak. In die Sunday Times (Augustus 1999) was dit aangedui dat Suid-Afrika In spanningsvolle samelewing is en dit word al hoe moeiliker om ondersteuning te vind, aangesien gesinsnetwerke nie sterk genoeg is nie. en Feit wat baie duidelik blyk, is dat - sonder ondersteuning - stres verskillende verhoudinge en omgewings beïnvloed. Verder is daar in hierdie studie tot die gevolgtrekking gekom dat die onderwysprofessie ook oor die potensiaal beskik om spanningsvol te wees en die werksomgewing te beïnvloed. Daar is bevind dat en gebrek aan doeltreffende stresbestuur enbelangrike afname in gesondheid tot gevolg het, asook ontevredenheid onder onderwysers en en onvermoë om volgens die gewenste gehalte te presteer (vergelyk 6.1). Die literatuuroorsig het ook aan die lig gebring dat beide tevredenheid en prestasie verband hou met belonings (Steyn & Van Wyk 1999:37): • Belonings het enmeer direkte invloed op die oorsaak van tevredenheid as op prestasie. • Belonings met die oog op voortgesette prestasie het weer op sy beurt prestasie tot gevolg. Hierdie navorsi

English: South Africa has been going through various changes since 1991. Education was no exception. Unfortunately, change also brings about uncertainties, which is exactly what the poor matric results brought to the minds of educators. Since many state-aided schools opened their doors to disadvantaged learners, poor matric results prevailed year after year. In 1997 a task-group was set up to examine the situation and find reasons for the complete collapse of a culture of learning and teaching. All stake-holders are responsible for the collapse of the culture of learning and teaching. Learners, teachers, parents, principal, governing bodies as well as departmental officials should accept joint responsibility for the present situation. In order to restore the culture of learning and teaching the Department of Education should not only try to improve the teacher-learner ratio, but should train teachers to become sensitive to the individual needs of learners, whether it may be social class differences or their individual cognitive abilities. Teachers should be guided towards developing their own potential in order to be optimistic, friendly and open to the needs of learners and the educative process. All of these mentioned factors would then lead to the creation of an inviting, positive learning environment which is conducive to facilitate effective learning. The principles of Invitational Education sets the scene for creating an inviting learning atmosphere through viewing learners as able, responsible and valuable. Teachers' behaviour is aimed at being intentionally inviting. Through this stance, they show their optimism and affirmative attitude towards teaching which in return brings forth more positive attitudes from the learners. Building learners self-confidence by making them feel special and proud, motivate them to reaching their full potential. Conflict is resolved in a constructive manner and policies and programmes are tailored to the learners' needs and to, Afrikaans: Suid-Afrika het verskeie verandering ondergaan sedert 1991. Onderwys was geen uitsondering nie, Verandering bring ongelukkig onsekerheid mee, wat presies is wat die onderwys-owerhede ervaar het by aanskoue van die swak matriek-uitslae. Sedert verskeie staat-gesubsidieerde skole hul deure oopgemaak het vir alle bevolkingsgroepe is elke jaar se matriek-uitslae meer kommerwekkend as die vorige. In 1997 is entaakgroep aangewys om die saak indringend te ondersoek. Wat is die oorsaak vir die ineenstorting van enkultuur van leer en onderrig? Alle betrokkenes blyk skuldig te wees! Leerders, onderwysers, hoofde, ouers, beheerrade and owerhede moet gesamentlik verantwoordelikheid aanvaar vir die . gebrek aan enkultuur van leer en onderrig. In enpoging om die situasie te verbeter, moet die owerhede nie net kyk na en beter onderwyser-leerder verhouding nie, maar ook onderwysers oplei wat meer sensitief is vir die behoeftes van die leerders. Hierdie behoeftes wissel van (sosiale) klasseverskille tot individuele kognitiewe vermoëns. Onderwysers behoort opgelei te word om hulle eie potensiaal te ontwikkel. Op hierdie wyse kan hulle meer vriendelik en toeganklik wees vir leerders se behoeftes. AI hierdie faktore sal lei tot die daarstelling van enmeer positiewe leeromgewing wat beter leer sal fasiliteer. Die beginsels van Uitnodigende onderwys dek die tafel vir die daarstelling van en uitnodigende leeromgewing waar leerders as waardevol, verantwoordelik en bekwaam beskou word. Onderwysers se gedrag moet daarop gemik wees om uitnodigend van aard te wees. Hierdeur sal hulle vir die leerders wys dat hulle optimisties en doelgerig is ten opsigte van hul roeping as onderwysers. Deur uitnodigende gedrag, sal leerders se selfvertroue toeneem. Deur leerders trots op hulle self en spesiaal te laat voel, word leerders gemotiveer om hul potensiaal te bereik. Konflik word op konstruktiewe wyse hanteer. Selfs programme en beleidsdokumente word met inagneming van die leerders se behoe

English: This research presents a socia-educational evaluation of the pre-school initiatives in the Nongoma district of KwaZulu-Natal. The researcher is of the opinion that socio-educatienat environmental factors in the rural areas do not support the successful implementation of pre-schooling initiatives. The historical background, in this research highlights certain social environmental factors in the rural areas. These factors translate into the school situation and consequently influence the educational effort. The literature review has shown that these factors can positively or negatively affect the educational efforts including the pre-school initiatives. The responses of the emperical research revealed that on the social scene, societal living conditions characterised by poverty, low educational attainments by the parents, ignorance of pre-school benefits, and poor communication channels across the social spectrum limit parental participation in a meaningful and far-reaching way. This research indicates that the educators in the rural areas of KwaZulu-Natal lack adequate skills needed to effectively handle pre-schooling in the management domain as well as in the classroom situation. Educators do not receive sustained support from the Education Department, as well as from the iziphathimandla (i.e. people in authority such as inkosi of the tribe, or the induna of an area). Remoteness of the rural areas from the urban areas and the lack of resources further complicate problems experienced by the rural teachers, and may negatively affect school initiatives, including pre-schooling. In the light of the findings, this research recommends that the socio-educational problems surrounding pre-school initiatives be addressed in the following way: education stakeholders are urged to encourage community participation in school initiatives, as well as stress governmental equitable distribution of available educational resources., Afrikaans: Hierdie ondersoek gee 'n sosio-opvoedkundige evaluering van die voorskoolse inisiatiewe in die Nongoma distrik van KwaZulu-Natal. Die navorser is van mening dat sosio-opvoedkundige omgewingsfaktore in die plattelandse gebiede nie 'n ondersteunende bydrae lewer tot die suksesvolle implementering van voorskoolse inisiatiewe nie. Die historiese agtergrond van hierdie navorsing het die aandag gevestig op sekere sosiale omgewingsfaktore in die plattelandse gebiede. Hierdie faktore is verwant aan die skoolsituasie en het gevolglik 'n uitwerking op die opvoedkundige taak. Die literatuurstudie het getoon dat hierdie faktore die opvoedkundige taak, wat voorskoolse inisiatiewe insluit, positief of negatief kan beïnvloed. Die response van die empiriese ondersoek het aangetoon dat wat die sosiale omgewing betref, lewensomstandighede gekenmerk word deur armoede, die lae opvoedkundige peil van ouers, onkunde betreffende die voordele van voorskoolse onderrig en swak kommunikasiekanale dwarsoor die sosiale spektrum, sodat betekenisvolle en doeltreffende deelname deur ouers beperk word. Die navorsing het ook aangetoon dat die opvoedkundiges in die plattelandse gebiede op beide bestuursvlak en in die klaskamersituasie, nie oor voldoende vaardighede beskik om voorskoolse onderrig te hanteer nie. Opvoedkundiges kry nie behoorlike ondersteuning van die Department van Onderwys, of die iziphafhimandla (gesaghebbendes in the gemeenskap) nie. Die afgeleë plattelandse gebiede en die tekort aan hulpbronne dra by tot die probleem wat deur plattelandse onderwysers ondervind word, en mag skoolinisiatiewe, insluitend voorskoolse aktiwiteite, nadelig beïnvloed. In die lig van die bevindinge, word aanbeveel dat die sosio-opvoedkundige probleme wat met voorskoolse inisiatiewe ondervind word, aangespreek word deur onder andere, die volgende: Opvoedkundige rolspelers moet aangemoedig word om die gemeenskap te beinvloed om deel te neem aan gemeenskaplike skool inisiatiewe, asook om te beklem