ABSTRACT This study aimed at investigating the teaching of Biology and Physical Science practical works in Senior Secondary schools in the Zambezi Region, Namibia. The study was guided by four questions: 1. Did the teaching of Biology and Physical Science practical works in Senior Secondary schools in the Zambezi region follow the learning objectives outlined in the subjects’ curricula?; 2. What practical skills do the Biology and Physical Science teachers aim to achieve from the practical...
Abstract. We generate two new exact models for the Einstein–Maxwell field equations. In our models, we consider the stellar object that is anisotropic and charged with linear equation of state consistent with quark stars. We have a new choice of measure of anisotropy that is physically reasonable. It is interesting that in our models we regain previous isotropic results as special cases. Isotropic exact solutions regained include models by Komathiraj and Maharaj; Mak and Harko; and Misner ...
ABSTRACT Network Vulnerabilities are weaknesses that allow attackers to bypass communication systems or network security. This grants the attackers access to crucial information on victim’s computer systems. So, analysis of network vulnerabilities is highly recommended as it helps to identify them in order to ensure a secured network. The experiments for this study were carried out on three networking environments. The first one was the CIVE LAN (as the main target), the second one was the...
Abstract Stated preference (SP) experiments are becoming an increasing popular survey methodology for investigating air travellers’ choices. Analysis of this behaviour, which is an element of the demand prediction, helps for a better future planning and development of competing airlines. In this thesis, emphasis is stressed on the stated preferences of passengers in choosing between low-cost carriers (LCC) and full-service carriers (FSC). Binary logit and probit model and latent class mode...
This paper considers the estimation of stress–strength reliability when two independent exponential inverse Rayleigh distributions with different shape parameters and common scale parameter. The maximum likelihood estimator (MLE) of the reliability, its asymptotic distribution and asymptotic confidence intervals are constructed. Comparisons of the performance of the estimators are carried out using Monte Carlo simulations, the mean squared error (MSE), bias, average length and coverage prob...
Abstract In this study, natural dye-sensitized solar cells (NDSSCs) were fabricated using crude and purified natural dye extracts aimed at investigating the effect of purified natural dyes on the dye-sensitized solar cell (DSSC) performance. Ethanol and methanol solvents were used to extract natural dyes from Senna singueana flowers, Senna singueana leaves, Ximenia caffra fruits, and Bougainvillea glabra bracts. Liquid-liquid extraction (LLE) method was used to purify the ethanol and methano...
ABSTRACT Depression has been the number one disease, causing a high motility rate in the world, marking the need for new highly effective antidepressants that can alleviate the situation. Unfortunately, the price of carrying out experimentally the whole process of drug discovery and design costs an endeavor billion of money. Yet, computer-aided drug design is a cost-effective way of obtaining new potential drugs within a short period of time. A study helpful in designing potent drug candidat...
ABSTRACT Information on genetic variation of breeding materials helps maintain genetically diversity and sustains long term selection gain. Marama bean [Tylosema esculentum (Burchell) Schreiber] occurs naturally in arid, dry parts of Southern Africa and due to the high nutrient value of the seeds and tubers, rich in protein, oil and starch, is a potential crop for arid areas where few conventional crops can survive. Microsatellites are becoming the molecular marker system of choice because t...
ABSTRACT The purpose of this project was to study the antioxidant potential of selected Namibian Leafy Vegetables (NLV), using Total Phenolic Content (TPC), Total Flavonoid contents (TFC) as well as Diphenyl-1-picrylhydrazyl (DPPH), 2,2-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and Reducing Power (RP) assays. The study also aimed at detecting and characterizing eight phenolic acids (4- hydroxybenzoic, trans-ferulic, vanillic, gallic, syringic, sinapic and para-coumaric acids) ...
The Magombera forest is a home of endemic and endangered biological species such as Udzungwa red colobus monkey (Procolobus gordonorum) and the Magombera chameleon (Kinyongia magomberae). However, the forest is facing high threat of disappearing through resources extraction pressure from adjacent local communities. The project aimed at improving conservation of Magombera forest by involving the adjacent communities through provision of conservation education, restoration initiatives and bee k...
ABSTRACT Kinetic and mechanistic investigations on the reactions of ozone with phenol and some of its derivatives (hydroquinone, catechol, phloroglucinol, pentachlorophenol, pentabromophenol, 1,2- dimethoxybenzene, 1,4-dimethoxybenzene and 1,3,5-trimethoxybenzene) have been carried out. These compounds were chosen, as they can serve as models for compounds which are abundant in surface waters and wastewater. The scope of the investigation was widened by including dihydrogen sulfide, often a ...
Abstract T-cell proliferation studies are traditionally carried out with radioactive reagents or fluorescent reagents that require measurement with advanced technology instrumentation. We attempted to calibrate the optimal conditions suitable for the use of a non-radioactive assay for the measurement of a T-cell proliferation assay in bovine fascioliasis, but applicable to the study of other infectious diseases in our developing 'country setting, Crude antigen extract was prepared from 15 adu...
Physico chemical properties and consumer acceptance of instant cowpea powder for complementary food
ABSTRACT Radiation exposure during diagnostic X-ray examinations has been widely reported as one of the sources of cancer induction. Information on X-ray machine and exposure parameters are crucial to risk assessment, which in turn are important for optimization of radiation protection measures. The documentation of radiation risk in Nigeria is sparse and hence the effectiveness of radiation protection measures at diagnostic centres has not been well established. This work was aimed at measur...
Abstract A modification of Biot's pornelastic differential equi~tionsis made to include nrarrix-fluid interaction mech~ismsw hich assume n solid-fluid relaxation hnction coiipli~igc c~eflicient. Vulucs of physical propcrtics of scdi~iicntsn .rc incorporuted'into cqilationswhicl~d cfinc phnsc yelocity nnd attei~uatibnf or pcirous media which are dependent on the co~~posidteen sities of various medin (silt, and lnediu~na nd coqfse sand). The results enable us to coinpare tlie .atenuation and ve...