This collection is made up of pre and post research articles created by both staff and students from Faculty of Sciences https://repository.biust.ac.bw/handle/123456789/58 2026-04-10T12:23:59Z 2026-04-10T12:23:59Z Makubate, Boikanyo Donnan, Peter Dewar, John Thompson, Andrew McCowan, Colin https://repository.biust.ac.bw/handle/123456789/735 2026-03-30T10:27:46Z 2013-03-21T00:00:00Z

Cohort study of adherence to adjuvant endocrine therapy, breast cancer recurrence and mortality Makubate, Boikanyo; Donnan, Peter; Dewar, John; Thompson, Andrew; McCowan, Colin Background: Adjuvant endocrine therapy is recommended for women with oestrogen receptor-positive breast cancer, but many women do not take the medication as directed and they stop treatment before completing the standard 5-year duration. Methods: This retrospective cohort study conducted between 1993 and 2008 of all women with incident breast cancer, who are residing in the Tayside region of Scotland, examined adherence to prescribed adjuvant tamoxifen or aromatase inhibitors (AIs). Survival analysis examined the effect of adherence on all-cause mortality, breast cancer death and recurrence, using linked prescribing, cancer registry, clinical cancer audit, hospital discharge and death records. Results: A total of 3361 women with breast cancer were followed for a median 4.47 years (interquartile range (IQR) ¼ 2.04–8.55). The median overall adherence was 90% (IQR ¼ 90–100%), but the annual adherence reduced after a longer period from diagnosis. Low adherence of o80% was associated with poorer survival (hazard ratios ¼ 1.20; 95% confidence interval ¼ 1.03–1.40, P ¼ 0.019). There was no significant difference for low adherence over the treatment period and recurrence, or breast cancer death, but patients with high annual adherence for 5 years had better outcomes than those with 3 or less. Conclusion: Low adherence to all adjuvant endocrine therapy for women with breast cancer, whether tamoxifen or AI, increases the risk of death.

2013-03-21T00:00:00Z Ayugi, Brian Shilenje, Zablon Weku Babaousmail, Hassen Sian, Kenny Lim Kam Mumo, Richard Dike, Victor Nnamdi Iyakaremye, Vedaste Chehbouni, Abdelghani Ongoma, Victor https://repository.biust.ac.bw/handle/123456789/577 2024-06-14T06:31:40Z 2022-04-09T00:00:00Z

Projected changes in meteorological drought over East Africa inferred from bias‑adjusted CMIP6 models Ayugi, Brian; Shilenje, Zablon Weku; Babaousmail, Hassen; Sian, Kenny Lim Kam; Mumo, Richard; Dike, Victor Nnamdi; Iyakaremye, Vedaste; Chehbouni, Abdelghani; Ongoma, Victor The ongoing global warming has caused unprecedented changes in the climate system, leading to an increase in the intensity and frequency of weather and climate extremes. This study uses the sixth phase of Coupled Model Intercomparison Project (CMIP6) data to investigate projected changes in drought events over East Africa (EA) under four Shared Socioeconomic Pathway (SSP) emission scenarios (SSP1-2.6, SSP2-4.5, SSP3-4.0, and SSP5-8.5). The CMIP6 data are bias-corrected using a quantile mapping method, with the Climatic Research Unit’s precipitation dataset as reference. Drought is quantified using the standardized precipitation index and different measures of drought are estimated: drought duration, drought frequency, drought severity, and drought intensity. Evaluating the accuracy and reliability of historical data before and after bias correction demonstrates the importance of the approach. The overall distribution after bias correction depicts a close agreement with observation. Moreover, the multi-model ensemble mean demonstrate superiority over individual Global Circulation Models. Projected future changes show enhancement in precipitation over most parts of EA in the far future under different SSP scenarios. However, the arid and semi-arid regions are expected to receive less amount of precipitation, whereas the highlands and lake regions are expected to receive a larger amount of precipitation increase. Furthermore, the dry areas of EA are likely to experience more frequent drought events with longer duration, stronger intensity, and severity in the far future. Overall, this study identifies possible drought hotspots over EA, enabling early preparation for such events.

2022-04-09T00:00:00Z Tsenang, Mmaabo Pheko, Tshepo Mokgadi, Janes Phokedi, Gothatamang Norma https://repository.biust.ac.bw/handle/123456789/574 2024-06-14T06:27:25Z 2022-10-25T00:00:00Z

A validated liquid–liquid extraction method for the quantitative analysis of ethanol in the different types of home-brewed alcoholic beverages of Botswana using gas chromatography flame ionization detector Tsenang, Mmaabo; Pheko, Tshepo; Mokgadi, Janes; Phokedi, Gothatamang Norma Home-made alcohol-related deaths are a significant public health issue which is often overlooked. To date, approxi-mately 30 people have died following the consumption of home brewed alcoholic beverages in Botswana. The process of brewing such alcoholic beverages remains unmonitored and makes it difficult to pinpoint the cause of these deaths. Ethanol content in these beverages is thought to be high and therefore contributing towards the deaths. The aim of this research was to develop and validate a method for the quantification of ethanol in the different types of home-brewed alcoholic drinks of Botswana.

2022-10-25T00:00:00Z Wafula, Henry Juma, Albert Sakwa, Thomas Musembi, Robinson Simiyu, Justus https://repository.biust.ac.bw/handle/123456789/516 2023-02-01T08:40:02Z 2016-07-22T00:00:00Z

A surface photovoltage study of surface defects on Co-doped TiO2 thin films deposited by spray pyrolysis Wafula, Henry; Juma, Albert; Sakwa, Thomas; Musembi, Robinson; Simiyu, Justus Surface photovoltage (SPV) spectroscopy is a powerful tool for studying electronic defects on semiconductor surfaces, at interfaces, and in bulk for a wide range of materials. Undoped and Cobalt-doped TiO 2 (CTO) thin films were deposited on Crystalline Silicon (c-Si) and Flourine doped Tin oxide (SnO 2 :F) substrates by chemical spray pyrolysis at a substrate temperature of 400 °C. The concentration of the Co dopant in the films was determined by Rutherford backscattering spectrometry and ranged between 0 and 4.51 at %. The amplitude of the SPV signals increased proportionately with the amount of Co in the films, which was a result of the enhancement of the slow processes of charge separation and recombination. Photogenerated holes were trapped at the surface, slowing down the time response and relaxation of the samples. The surface states were effectively passivated by a thin In 2 S 3 over-layer sprayed on top of the TiO 2 and CTO films.

2016-07-22T00:00:00Z