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Gaborone, Botswana

The Botswana International University of Science & Technology, also known as BIUST, is an International university located in the town of Palapye, Botswana. It is the Southern African nation's second university, after the University of Botswana in the country's capital, Gaborone. The location of the University is a 2,500 hectare site of gently sloping land the outskirts of Palapye. Wikipedia.

Ajayi O.O.,Covenant University | Fagbenle R.O.,Obafemi Awolowo University | Katende J.,Botswana International University of Science and Technology | Aasa S.A.,Covenant University | Okeniyi J.O.,Covenant University
International Journal of Energy and Environmental Engineering | Year: 2013

This study analyzed the electricity generation potential from wind at Kano, Nigeria (12.05°N; 08.2°E; altitude 472.5 m; air density 1.1705 kg/m3). Twenty one years (1987 to 2007) monthly mean wind speed data at a height of 10 m were assessed from the Nigeria Meteorological Department, Oshodi. The data were subjected to different statistical tests and also compared with the two-parameter Weibull probability density function. The outcome shows that the average monthly wind speed ranged from 6.6 to 9.5 m/s. Seasonally, average wind speeds ranged between 6.6 to 8.5 m/s and 7.4 to 9.5 m/s for dry (October to March) and wet (April to September) seasons, respectively. Also, estimated monthly wind power ranged between 3.6 and 12.5 MWh/m2. The most probable and maximum energy carrying wind speeds were also determined and the two parameters of the Weibull statistics were found to lie between 2.1 ≤ k ≤ 4.9 and 7.3 ≤ c ≤ 10.7, respectively. These results indicate that wind speeds at Kano may be economically viable for wind-to-electricity at and above the height of 10 m. In addition, five practical turbine models were assessed for the site's wind profile, with results suggesting strong economic viability. © 2013 Ajayi et al.

Eze P.N.,Botswana International University of Science and Technology | Knight J.,University of Witwatersrand | Evans M.,University of Witwatersrand
Geomorphology | Year: 2016

Three pedons on the alluvial terraces of the Sabie-Sand River Basin within Kruger National Park, South Africa, were studied to improve our understanding of recent environmental changes, and assess degree of chemical weathering and pedogenesis in the area using geochemical and micromorphology proxies. Particle-size distributions were obtained using Malvern Mastersizer; soil geochemistry was determined by XRF and thin sections by routine laboratory procedures. The soils are predominantly sandy (> 94% sand in all samples). The mean phi-values of the soils had little variation suggesting that reworking of sediments upwards in individual profiles produced a more uniform pedogenesis rather than coming from different physical sources. Calcification is the dominant pedogenic process in these alluvial soils. The Chemical Index of Alteration (CIA) proved a more suitable index than Chemical Index of Weathering (CIW) for evaluating weathering in the terraces. The micromass and b-fabrics are mostly granostriated and partly brown mosaic speckled. MISECA values for the degree of soil development range from 4 to 9, which mean weakly to moderately-developed soils. Coarse secondary calcite nodules and coatings are responsible for cementation as observed in pedon 2, which suggests calcium carbonate precipitation from periodical flooding and evaporating groundwater events. The features and diagnostic properties of the soils on the alluvial terraces along the Sabie-Sand River provide evidence for land surface impacts of recent environmental changes in this internationally important conservation area. Precise dating of calcium carbonate precipitates is, however, needed to put the observed evidence into a wider geochronological perspective. © 2016 Elsevier B.V.

McCowan C.,University of Glasgow | Wang S.,Imperial College London | Thompson A.M.,University of Dundee | Makubate B.,Botswana International University of Science and Technology | Petrie D.J.,University of Melbourne
British Journal of Cancer | Year: 2013

Background:Low adherence to adjuvant tamoxifen is associated with worse health outcomes but little is known about the cost-effectiveness of high adherence.Methods:We conducted an economic evaluation using data for all women with incident breast cancer between 1993 and 2000 who were subsequently prescribed tamoxifen in the Tayside region of Scotland. Patient-level, lifetime Markov models evaluated the impact of high vs low adherence to tamoxifen using linked prescribing, cancer registry, clinical cancer audit, hospital discharge and death records. Direct medical costs were estimated for each patient and quality-of-life weights were assigned. Recurrence information was collected by case note review and adherence calculated from prescribing records with low adherence classed below 80%.Results:A total of 354 (28%) patients had a recorded recurrence and 504 (39%) died. Four hundred and seventy-five (38%) patients had low adherence over the treatment period, which was associated with reduced time to recurrence of 52% (P<0.001). Time to other cause mortality was also reduced by 23% (P=0.055) but this was not statistically significant. For an average patient over her lifetime, low adherence was associated with a loss of 1.43 (95% CI: 1.15-1.71) discounted life years or 1.12 (95% CI: 0.91-1.34) discounted quality-adjusted life years (QALYs) and increased discounted medical costs of £5970 (95% CI: £4644-£7372). Assuming a willingness to pay threshold of £25 000 per QALY, the expected value of changing a patient from low to high adherence is £33 897 (95% CI: £28 322-£39 652).Conclusion:Patients with low adherence have shorter time to recurrence, increased medical costs and worse quality of life. Interventions that encourage patients to continue taking their treatment on a daily basis for the recommended 5-year period may be highly cost-effective. © 2013 Cancer Research UK. All rights reserved.

Tirivarombo S.,Botswana International University of Science and Technology
Proceedings of the IASTED International Conference on Environment and Water Resource Management, AfricaEWRM 2014 | Year: 2014

This paper evaluates the impacts of climate change on agricultural droughts in the Zambezi River basin. The Standardised Precipitation Index (SPI) is used to estimate drought occurrence and severity, historically and in the near future (2064-2065). Outputs of three downscaled and bias-corrected Global Circulation Models (GCMs) under the A2 emissions scenario are employed to evaluate the impact of climate change on future droughts in the basin. Based on the three GCMs it is anticipated that the basin will experience a generally increasing but minimal trend in precipitation in the range of 0.3% to 12%, with increased normal conditions and the possibility of a lower frequency of occurrence of severe to extreme drought events. The study also reveals that there is uncertainty associated with the GCMs as to the magnitude and direction of change of the basin's response to future climate change.

Leseane K.,Oklahoma State University | Atekwana E.A.,Oklahoma State University | Mickus K.L.,Missouri State University | Abdelsalam M.G.,Oklahoma State University | Shemang E.M.,Botswana International University of Science and Technology
Journal of Geophysical Research B: Solid Earth | Year: 2015

We used aeromagnetic and gravity data to investigate the thermal structure beneath the incipient Okavango Rift Zone (ORZ) in northwestern Botswana in order to understand its role in strain localization during rift initiation. We used three-dimensional (3-D) inversion of aeromagnetic data to estimate the Curie Point Depth (CPD) and heat flow under the rift and surrounding basement. We also used two-dimensional (2-D) power-density spectrum analysis of gravity data to estimate the Moho depth. Our results reveal shallow CPD values (8-15 km) and high heat flow (60-90 mW m-2) beneath a ∼60 km wide NE-trending zone coincident with major rift-related border faults and the boundary between Proterozoic orogenic belts. This is accompanied by thin crust (<30 km) in the northeastern and southwestern parts of the ORZ. Within the Precambrian basement areas, the CPD values are deeper (16-30 km) and the heat flow estimates are lower (30-50 mW m-2), corresponding to thicker crust (∼40-50 km). We interpret the thermal structure under the ORZ as due to upward migration of hot mantle fluids through the lithospheric column that utilized the presence of Precambrian lithospheric shear zones as conduits. These fluids weaken the crust, enhancing rift nucleation. Our interpretation is supported by 2-D forward modeling of gravity data suggesting the presence of a wedge of altered lithospheric mantle centered beneath the ORZ. If our interpretation is correct, it may result in a potential paradigm shift in which strain localization at continental rift initiation could be achieved through fluid-assisted lithospheric weakening without asthenospheric involvement. ©2015. American Geophysical Union. All Rights Reserved.

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