Spelling suggestions: "subject:"southern africa"" "subject:"southern affrica""
21 |
An investigation in the use of satellite data to develop a geomagnetic secular variation model over Southern Africa.Nahayo, Emmanuel. January 2011 (has links)
Time variations of the geomagnetic field can be classified into two main categories
of internal and external origin with respect to the surface of the Earth. It has been
found that the variations that take place on longer time scales (~ 1 year and longer)
are commonly known as secular variation (SV) and are of internal origin. There is a
need to develop SV models using satellite data as the use of ground data is not always
possible with many limitations including the limited data points and lack of data over
ocean areas that are not easily accessible. Two regional geomagnetic field modelling
techniques namely polynomial surface modelling (PolyM) and Spherical Cap Harmonic
Analysis (SCHA) were applied to CHAMP satellite data recorded between 2001 and
2005 to investigate the use of satellite data to develop a geomagnetic SV model over
southern Africa. The restricted area of investigation is between 10° and 40° South in
latitude and between 10° and 40° East in longitude. The resulting regional models of
this investigation were validated against the two widely used global field models IGRF
10 and CHAOS using the available ground survey data obtained during the same period
over southern Africa. The results suggest that the regional field models can be derived
based entirely on satellite data. However, the regional SV models can be improved by
combining both high quality satellite and ground survey data, since they lack the high
quality of a global field model like CHAOS. / Thesis (M.Sc.)-University of KwaZulu-Natal, Westville, 2011.
|
22 |
In vitro studies and phytocompound analysis in Lessertia frutescens (Fabaceae)Shaik, Shakira. January 2011 (has links)
The cancer bush (Lessertia frutescens L.) is an important leguminous perennial native to
southern Africa and has been used for centuries in traditional medicine by the continent’s diverse
cultural groups. Like many other legumes, the seeds of this species exhibit dormancy. Moreover,
woody plants are typically difficult to propagate in in vitro culture systems. But in vitro shoot
cultures are valuable in providing an alternative means of deriving desired secondary metabolites
or phytocompounds, under controlled conditions. This study describes novel protocols for
breaking seed dormancy, rapid and efficient in vitro propagation, bioreactor culture, and
comprehensive phytochemical data following screening and analysis of in vitro and field extracts
of L. frutescens. Experiments using physical, mechanical and chemical pre-sowing treatments
were conducted to determine the germination response of this species. The results indicated that
seeds of L. frutescens exhibited exogenous dormancy due to the inhibitory effect of the hard coat
on germination. Seed dormancy was released by mechanical scarification in which 100 %
germination was achieved. In vitro propagation studies using single node explants in Murashige
and Skoog (MS) medium supplemented with combinations of different concentrations of
benzyladenine and naphthaleneacetic acid revealed a maximum number of 10 shoots per explant
in solid medium, and 12.9 shoots per explant in liquid medium inside a temporary immersion
bioreactor. Indirect shoot organogenesis and plant regeneration using rachis and stem segments
was achieved with the highest percentage of explants forming shoots (88.8 %) from rachis
explants cultured onto MS medium supplemented with thidiazuron. Direct shoot organogenesis
from hypocotyl and cotyledon segments was also achieved in L. frutescens. The highest shoot
regeneration using hypocotyls (83 %) was obtained in MS medium supplemented with kinetin
whilst the highest shoot regeneration using cotyledons (46 %) was obtained in MS medium
supplemented with kinetin in combination with benzyladenine. Successful rooting (up to 80 %)
and acclimatization (up to 90 % survival rate) was attained. Spectrophotometric and gravimetric
methods indicated that saponins were the most abundant, followed by phenolics, flavonoids and
then alkaloids in in vitro leaf extracts then in field leaf extracts and seed extracts, respectively.
After qualitative analysis these extracts were also found to contain tannins, phlobatannins and
cardiac glycosides of medicinal interest. By using gas and liquid chromatography the presence of
the medicinally important L-canavanine, gamma amino-butyric acid and D-pinitol was verified
in in vitro leaf, field leaf and seed extracts. In vitro leaves had higher quantities of all
compounds, except for D-pinitol. Phytocompound analysis of shoots derived from several of the
cytokinin-enhanced media showed that these organs contained higher quantities of L-canavanine
compared to the control. This study, therefore, highlights the potential techno-economic
production of medicinal phytocompounds from in vitro leaves of L. frutescens following large
scale production using the protocols described in this study. / Thesis (Ph.D.)-University of KwaZulu-Natal, Westville, 2011.
|
23 |
An application of SERVQUAL to determine customer satisfaction of furniture retailers in Southern Africa : a cross-national study / Shaun PrithivirajhPrithivirajh, Shaun January 2013 (has links)
Africa, and Southern Africa in particular, has been identified by both South African and
international retail chains as an area for growth. Because conflict on the continent has all but
dissipated, economic growth naturally follows political stability. Africa, with its wealth of
resources, provides attractive markets for international investors. This increased investment
leads to a growing middle class, with growing needs for goods and services. The reason for
the interest from organised retail is therefore obvious. The challenge, however, is that, given
the size of the individual markets in Southern Africa, it is not financially viable to have an
independent marketing strategy for each market. There is no cross-national empirical research that has measured customers’ expectations and perceptions, allowing marketers to develop financially viable marketing strategies. This research, which can be considered an exploratory study, attempted to fill that void. Quality is an elusive and indistinct construct, and as such, it is difficult to measure. A large body of customer satisfaction/dissatisfaction literature acknowledges the importance of expectations in the customers’ evaluation (perception) of their service experience. Although there are several models which have been used to measure service quality, SERVQUAL remains the most popular. It has been successfully adapted to a range of service and retail environments, more especially in emerging markets. This study also employs an adapted SERVQUAL instrument to measure customer satisfaction levels in Southern Africa. The main objective of this study was to investigate the similarities in and differences between the perceptions and expectations regarding service quality of the customer groups of retail stores in different Southern African countries in order to develop financially viable retail strategies. In order to achieve this, the following secondary objectives were identified: *To determine the applicability of the adapted SERVQUAL model in Southern African countries. *To determine, by means of a cross-national study, whether other dimensions of service quality are relevant in the development of a service quality model in a Southern African context. The research population constituted all the existing and potential customers of Beares, Ellerines and FurnCity stores in Namibia, Botswana, Zambia, Swaziland, Lesotho and South Africa. Six hundred questionnaires in total were distributed, one hundred being sent to different stores in each of the six countries. Stores were chosen from both rural and metropolitan areas. This was a convenience sample and an interviewer-administered survey. Existing and prospective customers were intercepted in the store and interviewed by store managers. The findings indicated that there were statistically significant differences between expectations and perceptions in two factors of the measuring scale. Although the measuring instrument SERVQUAL was found to be both valid and reliable, only two factors were loaded during the analysis stage, and, as a result, the adaptability of SERVQUAL is questionable. The effect of culture does not form part of the SERVQUAL measuring scale yet service quality literature indicates that national cultures affect both the perceptions and the expectations of service quality. / PhD (Business Management), North-West University, Vaal Triangle Campus, 2014
|
24 |
The role of the Industrial Development Corporation in regional development in Southern Africa.Thabede, Mthokozisi Herbert 09 June 2008 (has links)
Miss Carina Van Rooyen
|
25 |
Some aspects of the mission policy and practice of the Church of the Province of South Africa in Ovamboland, 1924-1960Mallory, Charles Shannon January 1971 (has links)
This thesis is a study that was originally inspired by the question, "What does it mean to be a Christian in rural Africa today?" While the Church needs to ask this question everywhere in the world, from experience the writer believes it is especially germane to the non-Western cultures of Africa and Asia. That experience is drawn from eight years' work among the Kwanyama tribe of Ovambos in the Ovamboland Anglican Mission. Hence, this study is confined to one rural African tribe as it came under 46 years' influence of one Christian denomination.
|
26 |
A theology of spiritual direction for the Presbyterian Church of Southern AfricaSnyman, Kevin January 1997 (has links)
This essay is written in response to a lacuna that appears to exist within the Presbyterian Church of Southern Africa with regard to the ancient and highly regarded ministry of spiritual direction. My primary assertion is that, in the light of what might be perceived of as a crisis of relevance in Presbyterian life and spiritual practice, spiritual direction offers one particular way of fostering an exciting and existentially relevant spirituality for the denomination. Through the hoped-for renewal brought about by direction, Presbyterians may well have something to say to a South Africa racked not only with violence and poverty, but also bored by an increasingly irrelevant Christianity. The essay traces that history of spiritual direction most apposite to Presbyterianism in South Africa. This includes an overview of aspects of the Celtic and African spiritual traditions with a view to finding any correspondence that would help to narrow the distance between the spirituality of its black and white members. It then asks questions about the character and tasks of directors. Highlighted is the task of fostering an awareness of God that is not purely ''heavenly minded", but is able to speak into the real issues facing Presbyterians today. The essay goes on to explore the relationship that should exist between director and directee, focussing for a moment on the direction necessary in the directee's prayer life. The essay comes full circle as it considers the implications of introducing direction more widely in this largely "directionless" denomination. As a microcosm of the country, divergent cultures are as much a reality in the P.C.S.A. as in the rest of South Africa. So respect for uniqueness and the practice of interpathy are encouraged as part of the familiarisation process. Throughout the essay, I attempt to show that spiritual direction is a means of allowing the directee to more clearly discern the voice of the Spirit, who constantly encourages the transcendence of self - viz. the breaking of and dying to old perceptions, habits and beliefs so that s/he might more fully enter into the mystery that one usually refers to as God.
|
27 |
Trade facilitation under the WTO multilateral system : the key to ensuring sustainable development in Southern Africa through intra-regional tradeJordaan, Ruan 05 October 2010 (has links)
No abstract available. / Dissertation (LLM)--University of Pretoria, 2010. / Centre for Human Rights / unrestricted
|
28 |
Taxonomic status of Saccostomus campestris (Rodentia: Cricetomyinae) from southern Africa : a multidisciplinary approachMaputla, N.W. (Nakedi Walter) 19 November 2008 (has links)
The pouched mouse, Saccostomus campestris Peters, 1846 from southern Africa shows a high degree of karyotypic variation where up to 16 variants (2n = 30–50) have been reported. This has led to a systematic uncertainty that the present study attempts to assess using: 1) cytochrome b (cyt b; 1077 bp) and 16S rRNA (528 bp) partial sequences; 2) G-banding cytogenetic data; and 3)geometric morphometric data of various views of the cranium and mandible. The results from these multidisciplinary analyses are broadly similar with phylogenetic analyses of the molecular data revealing the presence of two major lineages. The first lineage comprises the high diploid numbered 2n = 46 cytotype from KwaZulu-Natal Province, South Africa that is considered to be ancestral. The second lineage consists of multiple inland populations that are subdivided into: 1) a sub-lineage comprising samples from a large semi-arid area in the west; and b) a sub-lineage of small distinct populations of low migrations from the east. The cytogenetic data suggest that karyotypic variation within S. campestris from southern Africa is due to autosomal Robertsonian fusions, with evidence of geographic structuring where cytotypes with high diploid numbers originate from the mesic east, while those with low diploid numbers originate from the arid west. The reduction in chromosome number appears to be due to adaptation to cold and dry conditions in the arid west. The X-chromosome revealed three variants that arose from a single pericentric inversion followed by the addition of genetic material, possibly heterochromatin. Variant 1 is only present in the ancestral cytotype and is found in all cytotypes throughout southern Africa, variant 2 is found in cytotypes from areas with < 600 mm of annual rainfall, while variant 3, although only found in females, is sympatric with variant 2. Geometric morphometric analysis of karyotyped specimens showed no discernible patterns of variation among karyotypic variants except for some subtle but equivocal indication of the morphological distinctiveness of the 2n = 46 cytotype from KwaZulu-Natal. Collation of the molecular, cytogenetic, and geometric morphometric data in the present study suggest that S. campestris from southern Africa is monotypic. / Dissertation (MSc)--University of Pretoria, 2011. / Zoology and Entomology / unrestricted
|
29 |
Riding the wave of change : the transition process of FNBCraven, Chantell 15 August 2012 (has links)
M.Comm. / Riding the wave of change is a challenge that companies often take on but just as often fail in. First National Bank decided to take on such a challenge when they merged with FirstRand Ltd. Moving from a second to a third wave company was a challenge not only management faced, but all the employees of First National Bank. The wave change required changes in various aspects of the company, for example management styles, company structure and culture of the company. A performance decline was experienced during the process of restructuring. Therefore management had to ensure that employees were motivated and focused throughout the period of change. However is it possible to keep employees motivated and focused? During this process of change the atmosphere among employees was tense and stressful. How does management assure their employees that the change is beneficial for them as well as for the company? Managing the change and ensuring that it is successful is a responsibility that lies heavily on management's shoulders. How does management guarantee successful change management? The aim of this study is to examine how First National Bank and FirstRand ensured a successful third wave change.
|
30 |
An evaluation of southern Africa's elephant sub-populations as a metapopulationOlivier, Pieter Ignatius 13 August 2010 (has links)
Elephant management traditionally centers on reducing ecological impact and human-elephant conflict by controlling numbers. However, such an approach only deals with symptoms, and ignores the causes of the problem. Planning for cases when a species is a nuisance in some areas, but threatened in others, could benefit from the application of metapopulation theory. The theory offers a framework that is elegant, and have ecological as well as political appeal. Applying classic metapopulation theory to long-lived species that are widely distributed in stochastic environments where they can resist extinctions is problematic. However, empirical evidence for metapopulation structure may exist when applying more lenient criteria. I examined the literature for empirical support of classic criteria set by Hanski (1999) and for a more lenient sub-set of criteria proposed by Elmhagen&Angerbjörn (2001) for specifically mammals. I propose that for small mammals (≤5kg) the full complement of classic criteria must be applied to yield perspectives on population regulation and conservation. However, for large (>100kg) and medium sized (>5≤100kg) mammals only habitat discreteness, potential of demographic asynchrony and the likelihood of dispersal among sub-populations must be evaluated. Metapopulation theory could then be useful when constructing conservation plans that ensure the persistence of a species and contribute to forces that stabilize populations regionally. I evaluated the applicability of metapopulation theory to southern Africa’s elephant sub-populations. I identified 51 discrete administrative sub-populations that occurred in six conservation clusters. Population growth rates varied across space and time within and among conservation clusters. Some sub-populations and conservation clusters increased or decreased while others remained stable. Therefore, elephant populations in southern Africa were in demographic asynchrony, both on a local and regional scale. I also suggest that dispersal may occur among sub-populations within clusters. Consequently, the regional population is stabilized by emigration to, or immigration from neighboring sub-populations as a result of demographic asynchrony across an ecological gradient. Elephant populations across southern Africa thus adhered to one and could possibly adhere to all metapopulation criteria. Observed changes in elephant numbers could also be the result of survey error. To gain an understanding of how survey error could affect estimates, I used dung counts and measurements to estimate population size and construct an age structure for the elephants living in the Maputo Elephant Reserve in Mozambique. I suggest that dung surveys can yield population estimates with known precision and can be used in monitoring programmes aimed at assessing population trends - despite the fact that it can be affected by observer bias. In this thesis I show that metapopulation theory provides the opportunity of applying a spatio-temporal approach to elephant conservation that is not obsessed with numbers. When implementing metapopulation theory, management no longer have to centre on elephants, but can focus on the landscape as a spatially and temporally dynamic area. Local fluctuations in elephant numbers could be construed within a regional context, rather than implementing management strategies on a local scale. Such an approach will focus on the causes rather than the symptoms of the elephant problem and may contribute to the persistence of elephants as well as other components of southern African biodiversity. AFRIKAANS : Die ekologiese impak van olifante en konflik tussen mense en olifante word tradisioneel hanteer deur olifant getalle te beheer. Ongelukkig los so ʼn benadering net die simptome en nie die oorsaak van die problem op nie. Gevalle waar ʼn spesie ʼn problem is in sommige areas maar bedreig is in ander, kan baat vind by die toepasing van die metabevolkings teorie. Die teorie bied ʼn elegante raamwerk wat op ekologiese en politieke gebiede aanklank vind. Die toepasing van die klassieke metabevolkings teorie op lang lewende spesies wat wyd versprei voorkom in stochastiese omgewings waar hulle weerstand kan bied teen uitsterwings skep egter probleme. Emperiese bewyse vir ʼn metabevolkings struktuur kan egter voorkom waneer meer gematigde kriteria ondersoek word. Ek het die literatuur ondersoek vir emperiese ondersteuning vir die klassieke kriteria wat Hanski (1999) voorgestel het, asook vir ʼn meer gematigte sub-groep van kriteria wat deur Elmhagen&Angerbjörn (2001) vir spesifiek soogdiere voorgestel is. Ek stel voor dat die klassieke kriteria aangewend kan word om bevolkings van klein soogdiere (5≤kg) te reguleer, beter te kan verstaan en dan te bewaar. Vir groot (>100kg) en medium groot (>5≤100kg) soogdiere kan die metabevolkings teorie net gebruik word as die bestaan van aparte habitate, demografiese asinkronie en die potensiaal van verstrooing tussen tussen subbevolkings bewys kan word. Die metabevolkings toerie kan dan gebruik word om bewarings inisiatiewe in te stel wat spesies in staat sal stel om voort te bestaan en oor die streek te stabiliseer. Ek het die toepasbaarheid van die metabevolkings teorie vir suidelike Afrika se olifant sub-bevolkings ondersoek. Ek het 51 aparte administratiewe sub-bevolkings geidentifiseer wat in ses ‘bewaringsklosse’ voorkom. Bevolkings groeitempos het binne in en tussen bewaringsklosse gewissel. Sommige het of toegeneem of afgeneem terwyl ander stabiel gebly het. Olifant sub-bevolkings in Suider Afrika was dus in demografiese asinkronie, op ʼn lokale sowel as op ʼn streeks vlak. Ek het ook voorgestel dat verstrooing kan voorkom tussen sub-bevolkings binne in bewarings klosse. Die olifant bevolking van die streek word dus deur emigrasie na, of immigrasie van naburige sub-bevolkings as gevolg van demografiese asinkronie oor ʼn ekologiese gradient gestabiliseer. Olifant bevolkings in Suider Afrika het dus voldoen aan een, en kan potensieel voldoen aan alle metabevolkings kriteria. Opmerklike veranderinge in olifant getalle kan ook wees as gevolg van foute wat tydens tellings gemaak word. Om beter te verstaan hoe sulke foute bevolking skattings affekteer, het ek olifant mis tellings en metings gebruik om ʼn bevolking skatting en ouderdomsstruktuur vir olifante in die Maputo Olifant Reservaat in Mosambiek saam te stel. Ek stel voor dat mis opnames bevolking skattings kan lewer wat bekende presiesie het en dat dit gebruik kan word in moniterings programme wat neigings in olifiant bevolkings ondersoek - alhoewel sulke skattings beinvloed kan word deur die vooroordeel van waarnemers. In hierdie tesis toon ek aan dat die metabevolkings teorie ʼn geleentheid skep vir ʼn ruimtelike-tydelike benadering in olifant bewaring wat nie net op getalle fokus nie. Wanneer die metabevolkings teorie toegepas word, kan bestuur op die landskap as ʼn ruimtelike en tydsgebonde dinamiese area fokus, in plaas van net op olifant getalle. Lokale wisselings in olifant getalle kan binne in ʼn streek konteks geinterpreteer word, eerder as om bestuurs inisiatiewe net op ʼn lokale vlak in te stel. So ʼn benadering sal fokus op die oorsprong in plaas van die simptome van die olifant problem en mag bydra tot die voorbestaan van nie net olifante nie, maar ook tot die biologiese diversiteit van Suider Afrika. Copyright / Dissertation (MSc)--University of Pretoria, 2010. / Zoology and Entomology / unrestricted
|
Page generated in 0.0633 seconds