Browsing by Title
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Mpoloka, S.W. (Academic Journals. http://www.academicjournals.org/AJB, NaN, 2008)[more][less]
Abstract: Over the past few decades, there has been a depletion of the stratospheric ozone layer due to emissions of halogen-containing compounds of anthropogenic origin. This has resulted in a concomitant increase in solar ultraviolet-B radiation. High levels of UV-B radiation are responsible for multiple biologically harmful effects in both plants and animals. In plants, these effects include DNA damage, which often causes heritable mutations affecting various physiological processes, including the photosynthetic apparatus, protein destruction and signal transduction via UV-B photoreceptors. High UV-B levels introduce a number of different lesions, predominantly cyclobutane pyrimidine dimmers (CPDs) and pyrimidine (6-4) pyrimidinone products [(6-4) PPs] in the genome. These could adversely affect plant growth, development and morphology, especially the productivity of sensitive crop species. This paper reviews the genetic effects of long-term UV-B exposure in plants. URI: http://hdl.handle.net/10311/491 Files in this item: 1
Effects of prolonged.pdf (2.345Mb) -
Siele, M.P.; Mubyana-John, T.; Bonyongo, M.C. (Global Science Books http://www.globalsciencebooks.com/index.php?page=shop.product_details&category_id=1&flypage=shop.flypage&product_id=5&option=com_virtuemart&Itemid=56&vmcchk=1&Itemid=56, NaN, 2008)[more][less]
Abstract: Soil cover influences soil biological and chemical processes in various ways. The effects of soil cover (bare soil without litter, litter cover, Mopane tree canopy and grass cover) on soil respiration and microbial population at four sites in the Mopane woodland of north western Botswana were investigated. Soil respiration rates were measured using an infrared gas analyzer. Nitrifying bacterial populations were quantified by MPN on ammonium and nitrite calcium carbonate media, oligotrophs on 1% nutrient agar, actinomycetes on starch casein agar, bacteriovorous protozoans by MPN on sodium chloride agar baited with Enterobacter, and fungal biomass carbon using buried slides were also determined. Soil respiration in different habitats was significantly influenced by type of cover, diurnal temperature variations and soil moisture. Soils under cover showed significantly higher soil respiration than the bare soils. Autochthonous bacterial populations in the Mopane woodland soils consisted mostly of oligotrophs which varied insignificantly between seasons. Fungi were the most dominant microorganisms in all the Mopane woodland soils, with biomass of 162.05 to 282.14 μg C/g soil in the wet season and 11.84 to 44.16 μg C/g soil in the dry season. Microscopic observation of buried slides revealed that fungi play a vital role in holding soil particles together in these soils. The results showed a strong positive relationship between changes in fungal biomass and fluctuation of soil respiration. However, no clear correlation was observed between the variation of soil respiration and other microbial populations (oligotrophic bacteria, actinomycetes, and nitrifying bacteria). Overall these results indicate that in soils under Mopane tree canopy, fungi contribute significantly to soil structure and soil respiration. Other microbial populations consist mostly of oligotrophs which show minimal seasonal variations. Soil moisture significantly influences seasonal fluctuation in soil respiration. URI: http://hdl.handle.net/10311/292 Files in this item: 1
The Effects of Soil Cover.pdf (6.625Mb) -
Abadjieva, T. (University of Botswana, NaN, 1998)[more][less]
Abstract: Investigations of the influence of various factors on the modulus of elasticity and deformability of different types of lightweight concrete are presented.The results show that the modulus are not constant and decrease with the increase of the level of applied stress. Aggregate proposity and volume fraction effects the modulus of elasticity and the modulus of deformability of concrete. Using different concrete mixes of varying strength, it was confirmed that the the modulus of elasticity and the comprehensive strength of concrete are directly proportioned. The modulus of elasticity per unit strength decreases with the age of concrete. As lightweight concrete is a heterogeneous, multiphase material, the volume fraction and modulus of elasticity of the principal constituents influence the modulus of elasticity of the composite material. URI: http://hdl.handle.net/10311/611 Files in this item: 1
Abajieva_BJT_1998.pdf (1.208Mb) -
Toteng, E.N. (Routledge http://dx.doi.org/10.1080/02508060802475415, NaN, 2008)[more][less]
Abstract: This article examines the adverse effects of a fragmented water management framework and the role of domestic water users on water conservation in Gaborone, the rapidly growing capital city of Botswana. There was a major drought in Botswana in 2004, which recurred in 2007. The drought seriously affected water availability in Gaborone, re-igniting the water conservation debate. Most urban households prior to 2004 did not practise water conservation, except in cases of enforced temporary measures, such as water restrictions and increased water tariffs imposed by the Water Utilities Corporation. From secondary evidence, the situation had not changed much in 2007. URI: http://hdl.handle.net/10311/363 Files in this item: 1
Toteng_WI_2008.pdf (851.6Kb) -
Mbaiwa, J.E.; Stronza, A.M. (Routledge (Taylor & Francis) www.routledge.com, January 19, 2010)[more][less]
Abstract: The Community-Based Natural Resource Management (CBNRM) program in Botswana aims to achieve biodiversity conservation and rural development in rich biodiversity areas like the Okavango Delta. CBNRM assumes that if rural communities derive benefits from natural resources, they will be obliged to use such resources sustainably. Using the sustainable livelihoods framework, this study analyzes the effects of tourism development through CBNRM on rural livelihoods at Khwai, Sankoyo and Mababe in the Okavango Delta, Botswana, using primary and secondary data sources. Results of long-term surveys and in-depth interviews indicate that the three communities have forgone traditional livelihood activities such as hunting and gathering, livestock and crop farming to participate in tourism through CBNRM. Livelihoods in these villages have been improved as a result. Basic needs such as shelter, employment and income and social services like water supply systems, transportation, scholarships and payment of funeral expenses are now provided to community members and funded with income from CBNRM. Social capital has been built up in order to agree, manage and develop the CBNRM process. These results show that tourism development in these villages is achieving its goal of improved livelihoods, contradicting claims that community development projects are failing to achieve rural development. URI: http://hdl.handle.net/10311/960 Files in this item: 1
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Mbaiwa, J.E.; Mbaiwa, O.I. (International Journal of Wilderness; http://ijw.wilderness.net/, December NaN, 2006)[more][less]
Abstract: This article examines the effects of veterinary fences on wildlife populations in the Okavango Delta, Botswana. Using data from secondary data sources, findings indicate that the existence of veterinary fences in the Okavango Delta contributes to the decline of wildlife species in Botswana. Veterinary fences are erected to control the spread of livestock diseases in order to protect the European Union beef market where Botswanaâ s beef is largely exported. Migratory wildlife species such as wildebeests, zebras, giraffes, buffalo, and tsessebes have their migratory routes blocked by veterinary fences and hence die from dehydration and entanglements in the fence. Those that get trapped by the fence often become easy kill targets for poachers. Some of the animals have been observed walking along the fence trying to cross. The erection of veterinary fences indicates that the expansion of livestock production into wildlife areas threaten the survival of wildlife in Botswana. To address the problem, an integration of wildlife production with other sectors such as agricultural development should be made a priority at national and local policy levels. This means that the principles of sustainability should be given priority in the erection of veterinary fences in wildlife areas. URI: http://hdl.handle.net/10311/28 Files in this item: 2
license.txt (1.998Kb)mbaiwa_int_j_wilderness_2006.pdf (338.1Kb) -
Mazimba, O.; Masesane, I.B.; Majinda, R.R. (Elsevier Science Ltd, http://www.elsevier.com/locate/tetlet, NaN, 2011)[more][less]
Abstract: An efficient total synthesis of flavans from the reactions of salicylaldehyde and acetophenone derivatives is reported. The synthesis involves preparation of chalcones through an aldol reaction followed by reduction of both the double bond and the ketone using NaBH4 and an acetic acid mediated cyclization. Methoxy groups on the aromatic rings did not affect significantly the yields of the procedure. URI: http://hdl.handle.net/10311/1027 Files in this item: 1
Mazimba_TL_2011.pdf (204.0Kb) -
Forcheh, N. (Wiley-Blackwell, www.wiley.com/wiley-blackwell, NaN, 2002)[more][less]
Abstract: Summary. Ehrenberg presented the simple law-like relationship log(w) = 0.8h + 0.4 ? 0.04 between the weight and height of children aged 5-13 years. Several researchers have confirmed that this relationship holds, irrespective of the child's ethnic, racial, gender and social class. In anthropometry, a weight-height relationship is used to measure the nutritional status of children. For this purpose, the World Health Organization have adopted the National Center for Health Statistics population as the international reference population. The relationship between the World Health Organization-National Center for Health Statistics anthropometric standards and Ehrenberg law-like relationship is examined. Differences between the weight-for-height relationship in anthropometry and the law-like relationship between weight and height for children are small and can be attributable to functional differences. It is found that an Ehrenberg law-like relationship can be extended to include children who are under 5 years old. Criteria for using the law-like relationship to assess the nutritional status of these children are thus suggested. The criteria are evaluated using anthropometric data of a sample of 513 children from a rural district of Botswana. The results indicate that the proposed method of using the law-like relationship to assess nutritional status is much simpler and at least as reliable as the existing methods in anthropometry. Description: Symbols on the abstract may differ from the original abstract URI: http://hdl.handle.net/10311/1055 Files in this item: 1
Forcheh_JRSS.A_2002.pdf (2.588Mb) -
Masale, M. (Elsevier Science Ltd. http://www.elsevier.com/wps/find/journaldescription.cws_home/622948/description#description, NaN, 2008)[more][less]
Abstract: A calculation is presented on the scattering rates of electrons via the bulk spectrum of longitudinal optical phonons near a current-carrying core of radius R employing the Frohlich interaction Hamiltonian. The electrons are mainly confined near the core by an electric potential and are also under the influence of the current-induced spatially inhomogeneous static azimuthal magnetic field. The external magnetic field lifts the double degeneracy of the non-zero electron's axial wave number (kz ) states, while that of the nonzero azimuthal quantum number (m) states is preserved. In fact, the kz < 0 electron's energy subbands are found to be characterized by minima in their variations with the field. The intrasubband scattering rates show a remarkable behavior in their variations with the field. First, for weak electric potential of the nanosystem, these exhibit a strong, nonetheless inharmonic, oscillatory behavior in their variations with the field. The oscillations are, however, smoothed out as the strength of the electrical potential is increased, commencing at lower values of the field, within the same range of values of the field used. Second, for the same strength of the electric potential, there arise phase variations of the scattering rates in their variations with the field, resulting from the variation in the electron's axial wave number. URI: http://hdl.handle.net/10311/232 Files in this item: 2
license.txt (1.998Kb)Masale_SM_2008.pdf (1.267Mb) -
Nindi, M.M.; Kgarebe, B.V.; Wolfender, J.L.; Abegaz, B.M. (John Wiley & Sons, Ltd., NaN, 1999)[more][less]
Abstract: Three naphthalenic derivatives, four flavonoids and two of the four anthraquinones previously isolated from the leaves of Rhamnus prinoides were successfully ionised under electrospray ionisation conditions. These compounds were subsequently detected in the leaf extract of the plant using electrospray liquid chromatography–mass spectrometry (LC–ESI–MS). The potential of LC–ESI–MS for screening a leaf extract, with the focus on the suitability of the method for assaying the bitter principle, geshoidin, of this commercially important plant, is presented. URI: http://hdl.handle.net/10311/290 Files in this item: 1
Electrospray Liquid.pdf (1.464Mb) -
Thupayagale-Tshweneagae, G.; Seloilwe, E.S. (Informa Healthcare, http://informahealthcare.com/journal/mhn, NaN, 2010)[more][less]
Abstract: A Heideggerian hermeneutic phenomenological approach was used to investigate the lived experience of women in Botswana who had experienced emotional abuse in intimate relationships. Hermeneutic phenomenologyis concerned with the human experience as it is lived. Ten educated Botswana women who had formal employment and have been in intimate relationships for longer than ten years, narrated their life experiences with abusive men. Extensive interviews took place over a six month period. Sociocultural practices in Botswana emerged as salient factors that contribute to emotional abuse and predispose womento mental illness. Entwined in these cultural practices are issues of age, ethnicity, payment of lobola (bride price), financial standing, change of name, and relocation to the man's residence. Education and employment seem to worsen the abuse. Depression and anxiety are common results of abuse. Understanding how the sociocultural factors perpetuate abuse can assist nurses in the way they provide health care services to women. URI: http://hdl.handle.net/10311/982 Files in this item: 1
Thupayagale-Tshweneagae_IMHN_2010.pdf (1.091Mb) -
Jain, P. (Emerald/www.emeraldinsight.com, NaN, 2007)[more][less]
Abstract: The purpose of this paper is to distinguish between information management (IM) and knowledge management (KM) and present the findings of small-scale research conducted to investigate KM practices in academic libraries in East and Southern Africa, and discussing the importance of KM and suggest the way forward. Design/methodology/approach – This research was undertaken in 20 university libraries in Africa using a questionnaire survey to investigate the current practices in university libraries in Africa to discover whether these libraries are practising KM or IM. Findings – This survey results seem to suggest that currently most participating libraries are practising IM. A majority of 65 per cent of the participants considered themselves information managers. Research limitations/ implications – This survey have had some limitations: one, all the participants were University librarians; two, due to the unavailability of contact addresses, the survey could cover only eight African countries. Future research should include a broader spectrum of participants to have an in-depth knowledge related to KM. Practical implications – This paper has practical implications for those who are not fully aware of the importance of KM, how KM can be used to gain a competitive advantage; to break financial and technological constraints; and to satisfy escalating user needs. Originality/value – Not much has been done in Africa to explore KM practices in University libraries, this paper contributes towards filling that gap and adds to KM literature in general and offers empirical support to KM concept. This paper discusses the benefits of KM and offers several recommendations to facilitate KM practices in university libraries in East and Southern Africa. URI: http://hdl.handle.net/10311/874 Files in this item: 1
Jain_LR_2007.pdf (1.409Mb) -
Jain, P. (Emerald, www.emeraldinsight.com, NaN, 2006)[more][less]
Abstract: Purpose – The purpose of the paper is to explore the role of information and communication technology (ICT) using a knowledge management (KM) approach. The knowledge in the context of this paper refers to indigenous knowledge. Design/methodology/ approach – The paper is based on a literature review. Findings – The discussion suggests that, in spite of various infrastructural limitations in Africa, KM applications can still play a vital role in indigenous knowledge management and consequently empowering Africa’s development. Research limitations/ implications – The major hindrance is the fact that Africa has thus far achieved little on its own; rather it has been emulating the progress made in the developed world. Because of this, there is a scarcity of in-depth knowledge related to an African context. In truth, some areas in which ICT has the potential to change, pertaining to the economy and society, have not been observed in any way. More research is required to identify specific needs of a country. Practical implications – The paper supposes that in spite of all these variations and implications KM can be adapted for indigenous knowledge. The paper contributes in terms of the literature review to showing how tacit knowledge can be managed using ICT. It can be useful for the researchers and knowledge workers. Recommendations are made concerning what needs to be done to improve ICT conditions in Africa such as: ICT policy formulation; literacy programs; legal and regulatory framework; manpower training; and empowerment of local people. Originality/value – Little has been done in Africa to explore the potential of using ICT as a mechanism with a knowledge management approach, in the thrust of Africa’s development. This paper proposes how it is possible to use ICT to manage and disseminate indigenous knowledge. URI: http://hdl.handle.net/10311/846 Files in this item: 1
Jain_EL_2006.pdf (1.502Mb) -
Mbaiwa, J.E. (Elsevier http://www.doi:10.1016/j.tourman.2003.11.005, NaN, 2005)[more][less]
Abstract: This paper draws on the dependency paradigm to explain the development of enclave tourism and its socio-economic impacts in the Okavango Delta, Botswana. Using both primary and secondary data source, the study indicates that international tourists, foreign safari companies and investors dominate the tourism industry in the Okavango Delta. The foreign domination and ownership of tourism facilities has led to the repatriation of tourism revenue, domination of management positions by expatriates, lower salaries for citizen workers, and a general failure by tourism to significantly contribute to rural poverty alleviation in the Okavango region. Tourism as a result has a minimal economic impact on rural development mainly because it has weak linkages with the domestic economy, particularly agriculture. Because of its nature, tourism in the Okavango Delta cannot be described as being sustainable from a socio-economic perspective. In order to address problems of enclave tourism development and promote more inclusive and beneficial tourism development in the Okavango, there is need to adopt policies and strategies that will ensure that substantial amounts of tourism revenue are retained in the Okavango and Botswana. These strategies should also ensure that tourism development in the Okavango Delta has strong linkages with the rest of the economy in Botswana. URI: http://hdl.handle.net/10311/429 Files in this item: 1
Mbaiwa_TM_2005.pdf (2.402Mb) -
Oladiran, M.T.; Meyer, J.P. (Elsevier http://www.elsevier.com, NaN, 2007)[more][less]
Abstract: The energy-utilization over a 10-year period (1994–2003) has been analysed for the South African industrial sector, which consumes more primary energy than any other sector of the economy. Four principal sub-sectors, namely iron and steel, chemical and petrochemical, mining and quarrying, and non-ferrous metals/non-metallic minerals were considered in this study. Primary-energy utilization data were used to calculate the weighted mean energy and exergy efficiencies for the sub-sectors and then overall values for the industrial sector were obtained. The results indicate that exergy efficiency is considerably lower than energy efficiency in all the sub-sectors, particularly in mining and quarrying processes, for which the values were approximately 83% and 16%, respectively. The performance of exergy utilization in the industrial sector can be improved by introducing various conservation strategies. Results from this study were compared with those for other countries. URI: http://hdl.handle.net/10311/957 Files in this item: 1
Oladiran_AP_2007.pdf (792.0Kb) -
Meyer, J.P. (Elsevier Science Ltd, http://www.elsevier.com/locate/apenergy, NaN, 2007)[more][less]
Abstract: The energy-utilization over a 10-year period (1994–2003) has been analysed for the South African industrial sector, which consumes more primary energy than any other sector of the economy. Four principal sub-sectors, namely iron and steel, chemical and petrochemical, mining and quarrying, and non-ferrous metals/non-metallic minerals were considered in this study. Primary-energy utilization data were used to calculate the weighted mean energy and exergy efficiencies for the sub-sectors and then overall values for the industrial sector were obtained. The results indicate that exergy efficiency is considerably lower than energy efficiency in all the sub-sectors, particularly in mining and quarrying processes, for which the values were approximately 83% and 16%, respectively. The performance of exergy utilization in the industrial sector can be improved by introducing various conservation strategies. Results from this study were compared with those for other countries. URI: http://hdl.handle.net/10311/668 Files in this item: 1
Oladiran_AE_2007.pdf (589.3Kb) -
Oladiran, M.T. (Elsevier Science Ltd, http://www.elsevier.com/wps/find/journaldescription.cws_home/269/description#description, NaN, 1995)[more][less]
Abstract: Botswana depends heavily on imported petroleum products for all premium applications. However, there is an abundant reserve of coal and other alternative sources of energy. This paper presents the energy trends and the various options for harnessing the resources. The importance of energy conservation is also discussed. URI: http://hdl.handle.net/10311/670 Files in this item: 1
Oladiran_ECM_1995.pdf (958.6Kb) -
Uziak, J.; Loukanov, I. A. (Dalhousie University, NaN, 2009)[more][less]
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Gwebu, T.D. (Kluwer Academic Publishers, http://www.springerlink.com/content/102895/, NaN, 2002)[more][less]
Abstract: Like most African countries, Botswana contributes almost insignificantly to global greenhouse emissions (GHGs). In this context, some have argued that energy policy and legislative measures to regulate emissions in Botswana should not be accorded high priority. This is a misguided view when one considers that each country, no matter how under-industrialized, contributes to the overall global emission problem. Moreover, the least developed countries will have to industrialize in order to meet the increasing economic and social needs of their growing populations. For rapidly growing economies like Botswana, whose annual energy demand is projected to increase by about 4% for the next ten years, the importance of compiling accurate inventories of sources and sinks of GHGs and formulating environmentally-friendly policies can hardly be over- emphasized. The United Nations Framework Convention on Climate Change (UNFCCC) provides the ideal basis for the country-by-country investigations and management of global climatic change; specifically its nature, properties, directionality, characteristics and probable consequences. Botswana was a founding signatory of UNFCCC in 1992 and ratified the Convention in 1994. The country is also involved in regional cooperation efforts, within the Southern African Development Community, to enforce regulatory mechanisms to minimize GHG emissions from the energy sector. There exist certain energy-related institutions, policies, and regulations in the country which could mitigate the impact of GHG emissions on global warming. This paper, based on government and other relevant documentation, critically analyses Botswana’s energy sector policies in as far as they affect climate change. It is clear that much still needs to be done about energy policies in terms of proper formulation, monitoring, co-ordination, energy pricing and the exploration of energy alternatives to mitigate potentially negative impacts on climate change. URI: http://hdl.handle.net/10311/958 Files in this item: 1
Gwebu_GJ_2002.pdf (1.010Mb) -
Foster, J. D. G. (Tempus Publications http://www.ijee.ie/, NaN, 2002)[more][less]
Abstract: The economy of Botswana has grown rapidly since it became independent in 1966, but the population is only 1.7 million. Engineering construction projects are of large scale. The University of Botswana offers engineering degrees in four disciplines, under programs that cover ten semesters. The particular challenges to engineering education in Botswana, as well as the structure of the present and future University of Botswana programs, are described in this paper. Emphasis is placed on a wide range of student individual investigation and design work, and the benefits of a particular project to the student and the program are stated in an illustration. URI: http://hdl.handle.net/10311/704 Files in this item: 1
Uziak_IJEE_2002.pdf (769.0Kb)