Faculty of Natural Sciences

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Welcome to the scholarship of the Faculty of Natural Sciences.

The Faculty is developing a reputation as an important centre of research in South Africa. It equips graduates with solid academic and research skills and gives them the ability to succeed in the market place.

Electronic theses and dissertations are available in the Electronic Theses and Dissertations Repository.

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The 1.28 GHz MeerKAT DEEP2 Image
(2020) Asad, K; Cotton, W; Mauch, T
We present the confusion-limited 1.28 GHz MeerKAT DEEP2 image covering one qb » ¢ 68 FWHM primarybeam area with θ = 7 6 FWHM resolution and s =  m - n 0.55 0.01 Jy beam 1 rms noise. Its J2000 center position α = 04h 13m 26 4, δ = −80° 00′ 00″ was selected to minimize artifacts caused by bright sources. We introduce the new 64-element MeerKAT array and describe commissioning observations to measure the primary-beam attenuation pattern, estimate telescope pointing errors, and pinpoint (u, v) coordinate errors caused by offsets in frequency or time. We constructed a 1.4 GHz differential source count by combining a power-law count fit to the DEEP2 confusion P(D) distribution from 0.25 to 10 μJy with counts of individual DEEP2 sources between 10 μJy and 2.5 mJy. Most sources fainter than S ∼ 100 μJy are distant star-forming galaxies (SFGs) obeying the far-IR/ radio correlation, and sources stronger than 0.25 μJy account for ∼93% of the radio background produced by SFGs. For the first time, the DEEP2 source count has reached the depth needed to reveal the majority of the star formation history of the universe. A pure luminosity evolution of the 1.4 GHz local luminosity function consistent with the Madau & Dickinson model for the evolution of SFGs based on UV and infrared data underpredicts our 1.4 GHz source count in the range -5 log Jy 4   [ ( )] S -
16 S rDNA primers and the unbiased assessment of thermophile diversity
(Portland Press, 2004) Baker, Gillian; Cowan, Donald A.
Our understanding of thermophile diversity is based predominantly on PCR studies of community DNA. ‘Universal’ and domain-specific rRNA gene PCR primers have historically been used for the assessment of microbial diversity without adequate regard to the degree of specificity of primer pairs to different prokaryotic groups. In a reassessment of the published primers commonly used for ‘universal’ and archaeal 16 S rDNA sequence amplification we note that substantial variations in specificity exist. An unconsidered choice of primers may therefore lead to significant bias in determination of microbial community composition. In particular, Archaea-specific primer sequences typically lack specificity for the Korarchaeota and Nanoarchaea and are often biased towards certain clades. New primer pairs specifically designed for ‘universal’ archaeal 16 S rDNA sequence amplification, with homology to all four archaeal groups, have been designed. Here we present the application of these new primers for preparation of 16 S libraries from thermophile communities.
1D NiHPO4 nanotubes prepared using dissolution equilibrium as bifunctional electrocatalyst for high-efficiency water splitting
(Journal of Power Sources, 2021) Ji, Shan; Wang, Zining; Wu, Yutai
In this work, one-dimensional NiHPO4 nanotubes are successfully fabricated on nickel foam by hydrothermal reaction, in which a dissolution equilibrium between phosphates is controlled by tuning the proportion of the mixed solvent and amounts of KOH. As the dissolution equilibrium is broken, the morphology of NiHPO4 transfers from solid nanowires to hollow nanotubes. The resulting 1D NiHPO4 nanotubes exhibit good electrocatalytic activity and stability in oxygen evolution reaction (OER) and hydrogen evolution reaction (HER). Notably, a water-splitting voltage of 1.62 V at a current density of 10 mA cm􀀀 2 is obtained in an electrolyzer setup assembled using 1D NiHPO4 nanotubes as cathode and anode, demonstrating NiHPO4 nanotubes are promising catalysts for overall water splitting. Moreover, the revealed mechanism of forming tube morphology can be extended to fabricate other metal phosphates with hollow structures.
2-Arylnaphthoquinone analogues: Potential anti-TB and pro-apoptotic agents
(Green, I. R. et al. (2011). 2-Arylnaphthoquinone analogues: Potential anti-TB and pro-apoptotic agents. ARKIVOC, (x), 192-212. https://doi.org/10.3998/ark.5550190.0012.a16, 2011) Green, Ivan R; Sagar, Sunil; Swigelaar, Wendell
A useful library of substituted 2-arylnaphthoquinones prepared by reaction between the corresponding bromonaphthoquinones and arylboronic acids via Suzuki-Miyaura protocols has been established. Conversion of some of the products into new analogues was effected. The bisnaphthoquinone disospyrin 1 comprises two 7-methyljuglone units linked between C2 and C6. 1,2 Antimycobacterial activity studies performed on diospyrin 1 alerted the scientific community to the potential importance of this natural product3 which was soon followed by its first published synthesis by Yoshida and Mori in the same year.4 Subsequent studies, which included the synthesis and evaluation of related analogues of diospyrin 1 demonstrated the potential of this basic scaffold to be considered as an integral aspect for good antimycrobacterial activity.
2-phenoxyethanol as anaesthetic in removing and relocating 102 species of fishes representing 30 families from sea world to uShaka Marine World, South Africa
(AOSIS, 2008) Vaughan, D.B.; Penning, M.R.; Christison, K.W.
The South African Association for Marine Biological Research, incorporating Sea World, Oceanographic Research Institute and the Dolphinarium relocated from their old premises of 46 years on Durban’s beach front in March and April 2004 to the new Point Development’s marine theme park, uShaka Marine World in Durban, South Africa. Netting of fishes from the large exhibits could cause physical damage to struggling fishes, increasing the risk of opportunistic secondary bacterial infections (Inoue, dos Santos Neto & Morales 2004) which could not be treated in time for the opening of uShaka Marine World on 30 April 2004.
The 2020 release of the ExoMol database: Molecular line lists for exoplanet and other hot atmospheres
(Elsevier, 2020) Lynas-Gray, A.E.; Tennyson, Jonathan; Yurchenko, Sergey
The ExoMol database (www.exomol.com) provides molecular data for spectroscopic studies of hot atmospheres. While the data are intended for studies of exoplanets and other astronomical bodies, the dataset is widely applicable. The basic form of the database is extensive line lists; these are supplemented with partition functions, state lifetimes, cooling functions, Landé g-factors, temperature-dependent cross sections, opacities, pressure broadening parameters, k-coefficients and dipoles. This paper presents the latest release of the database which has been expanded to consider 80 molecules and 190 isotopologues totaling over 700 billion transitions. While the spectroscopic data are concentrated at infrared and visible wavelengths, ultraviolet transitions are being increasingly considered in response to requests from observers. The core of the database comes from the ExoMol project which primarily uses theoretical methods, albeit usually fine-tuned to reproduce laboratory spectra, to generate very extensive line lists for studies of hot bodies. The data have recently been supplemented by line lists derived from direct laboratory observations, albeit usually with the use of ab initiotransition intensities. A major push in the new release is towards accurate characterisation of transition frequencies for use in high resolution studies of exoplanets and other bodies.
3,3' Diindolylmethane mediated signalling and its role in Brassica napus L. responses to vanadium
(University of the Western Cape, 2016) Gokul, Arun; Keyster, Marshall
Anthropogenic activities such as mineral mining, improper watering practices, and the use of heavy metal contaminated fertilizers have caused an influx of heavy metals into arable lands. These heavy metals may have a negative impact on plant growth, as they are able to increase ROS species within plants resulting in plant metabolism deterioration and tissue damage. Heavy metals also have the ability to render important enzymes non-functional or may decrease their activity resulting in poor growth. Vanadium was used as the heavy metal of choice in this study, as South Africa is one of the top producers of this metal worldwide. In an effort to improve growth of crop plants, mechanisms have to be identified to increase growth under vanadium stress. One method to increase growth is the use of exogenously applied signalling molecules. In this study, one such compound 3,3' Diindolylmethane (DIM) was investigated to identify whether it had growth promoting properties.
3,3'-diindolylmethane improves drought tolerance of Zea mays through enhancing antioxidant activity
(University of the Western Cape, 2018) Basson, Gerhard Leroy; Ludidi, Ndiko; Keyster, Marshall; Gokul, Arun
Maize is one of the most abundantly produced cereals and contributes to about 40% of the global cereal production. This figure will have to increase in order to feed the ever-growing human population. One of the major environmental constraints that impact maize production is drought. Plants use antioxidant defences to cope with drought stress. Understanding and improving these defence mechanisms will be important to improve overall drought tolerance. A previous study done by Gokul and authors in 2016 showed that 3,3’-diindolylmethane (DIM) improves both seed germination and seedling shoot growth in Brassica napus. Plants belonging to the Brassicaceae family have the metabolic machinery to synthesize glucosinolates such as DIM, which play vital roles in physiological and stress responses. These responses have not been investigated in plants such as maize, which lack the machinery to produce DIM. Therefore, this study investigated the effects of exogenously applied DIM on the physiological and biochemical responses of maize under drought stress. Physiological parameters such as relative water content, chlorophyll content and lipid peroxidation, were determined in order to understand how drought and DIM , as separate or combined treatments, affected the plants. Additionally, proline accumulation was also assessed because free proline plays a role as an osmoprotectant during stress. The accumulation of ROS, namely hydrogen peroxide, was measured using spectrophotometric assays to determine how the above treatments affect ROS accumulation in maize. As a result of changes in the ROS content in due to the treatments, it would only be natural to investigate the changes in antioxidants as well. Given that hydrogen peroxide was the ROS to be measured, we therefore investigated the antioxidant enzymatic activities responsible for hydrogen peroxide scavenging. Therefore, changes in Ascorbate peroxidase (APX) and catalase (CAT) were assessed. An improved drought response was observed in maize plants treated with DIM as these plants had better ability to maintain their water status than when no DIM was applied. This is indicated by water-deprived plants treated with DIM having a higher RWC than water-deprived plant without DIM.
A 35-gene signature discriminates between rapidly- and slowly-progressing glioblastoma multiforme and predicts survival in known subtypes of the cancer
(BioMed Central, 2018) Fatai, Azeez A.; Gamieldien, Junaid
BACKGROUND: Gene expression can be employed for the discovery of prognostic gene or multigene signatures cancer. In this study, we assessed the prognostic value of a 35-gene expression signature selected by pathway and machine learning based methods in adjuvant therapy-linked glioblastoma multiforme (GBM) patients from the Cancer Genome Atlas. METHODS: Genes with high expression variance was subjected to pathway enrichment analysis and those having roles in chemoradioresistance pathways were used in expression-based feature selection. A modified Support Vector Machine Recursive Feature Elimination algorithm was employed to select a subset of these genes that discriminated between rapidly-progressing and slowly-progressing patients. RESULTS: Survival analysis on TCGA samples not used in feature selection and samples from four GBM subclasses, as well as from an entirely independent study, showed that the 35-gene signature discriminated between the survival groups in all cases (p < 0.05) and could accurately predict survival irrespective of the subtype. In a multivariate analysis, the signature predicted progression-free and overall survival independently of other factors considered. CONCLUSION: We propose that the performance of the signature makes it an attractive candidate for further studies to assess its utility as a clinical prognostic and predictive biomarker in GBM patients. Additionally, the signature genes may also be useful therapeutic targets to improve both progression-free and overall survival in GBM patients.
3D forensic crime scene reconstruction involving immersive technology: A systematic literature review
(Institute of Electrical and Electronics Engineers, 2022) Maneli, Mfundo A.; Isafiade, Omowunmi E.
Recreation of 3D crime scenes is critical for law enforcement in the investigation of serious crimes for criminal justice responses. This work presents a premier systematic literature review (SLR) that offers a structured, methodical, and rigorous approach to understanding the trend of research in 3D crime scene reconstruction as well as tools, technologies, methods, and techniques employed thereof in the last 17 years. Major credible scholarly database sources, Scopus, and Google Scholar, which index journals and conferences that are promoted by entities such as IEEE, ACM, Elsevier, and SpringerLink were explored as data sources. Of the initial 17, 912 papers that resulted from the first search string, 258 were found to be relevant to our research questions after implementing the inclusion and exclusion criteria.
3D static modeling and CO2 static storage estimation of the hydrocarbon-depleted charis beservoir, Bredasdorp basin, South Africa
(Natural Resources Research, 2023) Afolayan, Blessing Ayotomiwa; Opuwari, Mimonitu; Mackay, Eric
An essential greenhouse gas effect mitigation technology is carbon capture, utilization and storage, with carbon dioxide (CO2) injection into underground geological formations as a core of carbon sequestration. Developing a robust 3D static model of the formation of interest for CO2 storage is paramount to deduce its facies changes and petrophysical properties. This study investigates a depleted oilfield reservoir within the Bredasdorp Basin, offshore South Africa. It is a sandstone reservoir with effective porosity mean of 13.92% and dominant permeability values of 100–560 mD (1 mD = 9.869233 × 10–16 m2). The petrophysical properties are facies controlled, as the southwestern area with siltstone and shale facies has reduced porosity and permeability. The volume of shale model shows that the reservoir is composed of clean sands, and water saturation is 10–90%, hence suitable for CO2 storage based on petrophysical characteristics. Static storage capacity of the reservoir as virgin aquifer and virgin oilfield estimates sequestration of 0.71 Mt (million tons) and 1.62 Mt of CO2, respectively. Sensitivity studies showed reservoir depletion at bubble point pressure increased storage capacity more than twice the depletion at initial reservoir pressure. Reservoir pressure below bubble point with the presence of gas cap also increased storage capacity markedly.
3D-QSAR and docking studies of pentacycloundecylamines at the sigma-1 (σ1) receptor
(Elsevier, 2013) Geldenhuys, Werner J.; Novotny, Nicholas; Malan, Sarel F.; Van der Schyf, Cornelis J.
Pentacycloundecylamine (PCU) derived compounds have been shown to be promising lead structures for the development of novel drug candidates aimed at a variety of neurodegenerative and psychiatric diseases. Here we show for the first time a 3D quantitative structure–activity relationship (3D-QSAR) for a series of aza-PCU-derived compounds with activity at the sigma-1 (r1) receptor. A comparative molecular field analysis (CoMFA) model was developed with a partial least squares cross validated (q2) regression value of 0.6, and a non-cross validatedr2 of 0.9. The CoMFA model was effective at predicting the sigma-1 activities of atest set with an r2 >0.7. We also describe here the docking of the PCU-derivedcompounds into a homology model of the sigma-1 (r1) receptor, which was developed to gain insight into binding of these cage compounds to the receptor. Based on docking studies we evaluated in a [3H]pentazocine binding assay anoxa-PCU, NGP1-01 (IC50 = 1.78 lM) and its phenethyl derivative (IC50 = 1.54 lM). Results from these studies can be used to develop new compounds with specific affinity for the sigma-1(r1)
4-(Dimethylamino)pyridinium chlorosulfonate: A new ionic liquid exhibiting chlorosulfonic acid action as monoprotic Brönsted acid and no sulfonating reagent
(Journal of Molecular Liquids, 2021) Titinchi, Salam
Many papers considered chlorosulfonic acid as a sulfonating and sulfating agent, whereas our previous work and a few reports showed it acts as a monoprotic Brönsted acid. Therefore, in the present work, we decided to respond to this question by investigating the reaction between chlorosulfonic acid and DMAP. First, a new ionic liquid viz. 4-dimethylaminopyridinium chlorosulfonate was obtained, which its chemical structure was elucidated using different spectroscopic techniques. Another derivative, 4-dimethylaminopyridinium hydrogen sulfate, was also synthesized, which showed a similar NMR pattern. The NMR spectra analyses of reactants, the new ionic liquid, and 4 dimethylaminopyridinium hydrogen sulfate support the formation of 4-dimethylaminopyridinium chlorosulfonate. Therefore, the formation of N-sulfonic acid-4-dimethylaminopyridinium chloride or 4-dimethylaminopyridinium sulfate and the presence of an excess of chlorosulfonic acid and sulfuric acid were ruled out based on the spectroscopic results. Finally, the new ionic liquid's thermal behavior and thermal stability were investigated, and a possible mechanism was presented for its degradation based on a TGA/DTA analysis.
4-oxatricyclo[5.2.1.02,6]dec-8-ene-3,5-dione derivatives as nmda receptor- And VGCC blockers with neuroprotective potential
(MPDI, 2020) Egunlusi, Ayodeji O.; Malan, Sarel F.; Omoruyi, Sylvester Ifeanyi
The impact of excitotoxicity mediated by N-methyl-D-aspartate (NMDA) receptor overactivation and voltage gated calcium channel (VGCC) depolarization is prominent among the postulated processes involved in the development of neurodegenerative disorders. NGP1-01, a polycyclic amine, has been shown to be neuroprotective through modulation of the NMDA receptor and VGCC, and attenuation of MPP+-induced neurotoxicity. Recently, we reported on the calcium modulating effects of tricycloundecene derivatives, structurally similar to NGP1-01, on the NMDA receptor and VGCC of synaptoneurosomes. In the present study, we investigated novel 4-oxatricyclo[5.2.1.02,6]dec-8-ene-3,5-dione derivatives for their cytotoxicity, neuroprotective effects via attenuation of MPP+-induced neurotoxicity and calcium influx inhibition abilities through the NMDA receptor and VGCC using neuroblastoma SH-SY5Y cells. All compounds, in general, showed low or no toxicity against neuroblastoma cells at 10-50 μM concentrations. At 10 μM, all compounds significantly attenuated MPP+-induced neurotoxicity as evident by the enhancement in cell viability between 23.05 ± 3.45% to 53.56 ± 9.29%.
4-Oxatricyclo[5.2.1.02,6]dec-8-ene-3,5-dione derivatives as NMDA receptor- and VGCC blockers with neuroprotective potential
(MDPI, 2020) Egunlusi, Ayodeji O; Omoruyi, Sylvester I; Malan, Sarel F
The impact of excitotoxicity mediated by N-methyl-D-aspartate (NMDA) receptor overactivation and voltage gated calcium channel (VGCC) depolarization is prominent among the postulated processes involved in the development of neurodegenerative disorders. NGP1-01, a polycyclic amine, has been shown to be neuroprotective through modulation of the NMDA receptor and VGCC, and attenuation of MPP+-induced neurotoxicity. Recently, we reported on the calcium modulating effects of tricycloundecene derivatives, structurally similar to NGP1-01, on the NMDA receptor and VGCC of synaptoneurosomes. In the present study, we investigated novel 4-oxatricyclo[5.2.1.02,6]dec-8-ene-3,5-dione derivatives for their cytotoxicity, neuroprotective effects via attenuation of MPP+-induced neurotoxicity and calcium influx inhibition abilities through the NMDA receptor and VGCC using neuroblastoma SH-SY5Y cells. All compounds, in general, showed low or no toxicity against neuroblastoma cells at 10–50 µM concentrations. At 10 µM, all compounds significantly attenuated MPP+-induced neurotoxicity as evident by the enhancement in cell viability between 23.05 ± 3.45% to 53.56 ± 9.29%. In comparison to known active compounds, the derivatives demonstrated mono or dual calcium modulating effect on the NMDA receptor and/or VGCC. Molecular docking studies using the NMDA receptor protein structure indicated that the compounds are able to bind in a comparable manner to the crystallographic pose of MK-801 inside the NMDA ion channel. The biological characteristics, together with results from in silico studies, suggest that these compounds could act as neuroprotective agents for the purpose of halting or slowing down the degenerative processes in neuronal cells.
4-Oxatricyclo[5.2.1.02,6]dec-8-ene-3,5-dione Derivatives as NMDA Receptor- and VGCC Blockers with Neuroprotective Potential
(MDPI, 2020) Egunlusi, A; Malan, S; Omoruyi, S
The impact of excitotoxicity mediated by N-methyl-D-aspartate (NMDA) receptor overactivation and voltage gated calcium channel (VGCC) depolarization is prominent among the postulated processes involved in the development of neurodegenerative disorders. NGP1-01, a polycyclic amine, has been shown to be neuroprotective through modulation of the NMDA receptor and VGCC, and attenuation of MPP+-induced neurotoxicity. Recently, we reported on the calcium modulating effects of tricycloundecene derivatives, structurally similar to NGP1-01, on the NMDA receptor and VGCC of synaptoneurosomes.
5G wireless network support using umanned aerial vehicles for rural and low-Income areas
(University of the Western Cape, 2020) Maluleke, Hloniphani; Bagula, B.A.
The fifth-generation mobile network (5G) is a new global wireless standard that enables state-of-the-art mobile networks with enhanced cellular broadband services that support a diversity of devices. Even with the current worldwide advanced state of broadband connectivity, most rural and low-income settings lack minimum Internet connectivity because there are no economic incentives from telecommunication providers to deploy wireless communication systems in these areas. Using a team of Unmanned Aerial Vehicles (UAVs) to extend or solely supply the 5G coverage is a great opportunity for these zones to benefit from the advantages promised by this new communication technology. However, the deployment and applications of innovative technology in rural locations need extensive research.
An ∼600 pc view of the strongly lensed, massive main-sequence galaxy J0901: a baryon-dominated, thick turbulent rotating disk with a clumpy cold gas ring at z = 2.259
(The astrophysical journal, 2023) Baker, Andrew J.; Liu, Daizhong; Schreiber, N. M. Förster
We present a high-resolution kinematic study of the massive main-sequence star-forming galaxy (SFG) SDSS J090122.37+181432.3 (J0901) at z = 2.259, using ∼0.″36 Atacama Large Millimeter/submillimeter Array CO(3-2) and ∼0.″1-0.″5 SINFONI/VLT Hα observations. J0901 is a rare, strongly lensed but otherwise normal massive ( log ( M ⋆ / M ⊙ ) ∼ 11 ) main-sequence SFG, offering a unique opportunity to study a typical massive SFG under the microscope of lensing. Through forward dynamical modeling incorporating lensing deflection, we fit the CO and Hα kinematics in the image plane out to about one disk effective radius (R e ∼ 4 kpc) at an ∼600 pc delensed physical resolution along the kinematic major axis. Our results show high intrinsic dispersions of the cold molecular and warm ionized gas (σ 0,mol. ∼ 40 km s−1 and σ 0,ion. ∼ 66 km s−1) that remain constant out to R e; a moderately low dark matter fraction (f DM ∼ 0.3-0.4) within R e; and a centrally peaked Toomre Q parameter—agreeing well with the previously established σ 0 versus z, f DM versus Σbaryon, and Q's radial trends using large-sample non-lensed main-sequence SFGs. Our data further reveal a high stellar mass concentration within ∼1-2 kpc with little molecular gas, and a clumpy molecular gas ring-like structure at R ∼ 2-4 kpc, in line with the inside-out quenching scenario. Our further analysis indicates that J0901 had assembled half of its stellar mass only ∼400 Myr before its observed cosmic time, and the cold gas ring and dense central stellar component are consistent with signposts of a recent wet compaction event of a highly turbulent disk found in recent simulations. © 2023. The Author(s). Published by the American Astronomical Society.
A Community Pharmacy perspective on the epidemiology of antimicrobial drugs in the Kuilsriver urban area
(University of the Western Cape, 2017) Mhlanga, Miriam Rufaro; Obikeze, K
The epidemiology of drugs is 'defined as the manner in which drugs are used by doctors, nurses, pharmacists and patients. As such epidemiology of antimicrobial drugs is the manner in which this class of drugs is used by healthcare professional, patients or caregivers. Antimicrobial drugs have a pivotal role worldwide in preventing infections and treating infectious diseases. The challenge that lies in the health sector is to maintain antimicrobials' effectiveness by using them appropriately to avoid toxicity, adverse reactions and resistance among other problems. The world faces a future in which ten million people could die annually due to infections that are resistant to available antibiotics. Despite people already dying of drug-resistant infections in private and public hospitals, doctors are still prescribing antibiotics for viral infections, for which they have no effect. The aim of this research is to study the epidemiology of antimicrobial drugs and factors that lead to the inappropriate use of antimicrobials, which is resulting in a steep rise of antimicrobial resistance in the private sector from a community pharmacy perspective.
A comparative analysis of long-term variations of temperature and rainfall in rural and urban areas, and their effects on the estimation of design storms in Kenya
(University of the Western Cape, 2016) Gachahi, Lydiah Wangechi; Mazvimavi, Dominic
My Thesis aimed at expanding the current knowledge on how variations of temperature characteristics including the possible existence of urban heat islands (UHI) over urban areas of Kenya could be influencing rainfall characteristics, and to examine if the stationary extreme value distributionis still suitable for modeling urban storm designs in view of the global climate change. My hypothesis was that the floodingoccurring frequently in major urban areas of Kenya are due to increased rainfall caused by global climate change, and the urban heat island (UHI) effect. To put this perception into perspective, temperature and rainfall characteristics and their inter-relationships, of four of the major urban areas in Kenya namely, Nairobi, Mombasa, Kisumu, and Nakuru, were investigated. I obtained data from meteorological stations in and around each urban area, which had at least thirty (30) years of continuous monthly (or daily) temperatures and rainfall values, from the Kenya Meteorological Department. I checked the datasets for quality and missing values and adjusted where necessary before commencing with analysis. I sourced other supporting global dataset from various websites' data banks.I used various methods of data analysis which included; i) exploratory data analysis techniques such as the continuous wavelet transform (CWT), geographical information system (GIS) maps, and visual time series plots. In particular and unique in my Thesis was the use of the CWT method as a diagnostic tool to examine non-stationaritiesand variability of temperature and rainfall time series.

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