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Item Assessment of background radiation fin playgrounds of selected basic schools in the GA east municipal district, Accra, Ghana(University of Namibia, 2017) Taapopi, Erastus E.; Faanu, A.; Dampare, S.B.A study has been carried out in the play grounds of selected basic schools in the Ga East municipal district of Accra, Ghana, to determine the exposure of school children to the radiation emitted by Naturally Occurring Radionuclide Materials and trace elements. The activity concentrations of different radionuclides were determined using high purity germanium (HPGe) detector. The average activity concentrations of 238U, 232Th and 40K were found to be19.8±8.7, 29.1±16.3 and119.4±97.9 Bq ·kg−1 respectively. The average annual effective dose calculated from these activity concentrations was 0.04mSv which is below the dose limit of1 mSv/year recommended by the International Commission on Radiological Protection (ICRP) for public exposure control. Radiological hazard assessments were carried out and the Rn−222 concentration and exhalation rate were estimated to be 32.13 kBg ·m−3 and 0.016 Bg ·m−2 · s−1 respectively. These values are with in the world average values..Item Subjective well-being, psychological well-being and anxiety symptoms of medical and pharmacy students in Namibia(University of Namibia, 2017) Perstling, Martina; Nepolo, Emmanuel; Udjombala, N.; Nyarango, Peter; Karuaihe, M.; Hunter, Christian J.Medical and pharmacy students at the School of Medicine of Namibia underwent a survey investigating their level of mental well-being and anxiety symptoms. Not only were the two constructs, subjective well-being and psychological well-being positively inter- related but also correlated inversely with anxiety symptoms. Environmental mastery in the psychological well-being scale was negatively associated with anxiety (coefficient: -0.17, 95% CI: [-0.27,-0.7], p-value = 0.001). Supportive qualitative data brought some environmental challenges forward that were typical for medical and pharmacy students as these professions are fundamentally emotionally challenging, in addition to a taxing curriculum, work overload and time constraints influencing well-being negatively. Supplementary information contributed towards additional challenges which deviate from the common hardships of studying high profile professions such as medicine and pharmacy. Firstly, most of the students needed to migrate to the capital city to study, finding themselves in a new and unfamiliar environment; and, secondly poverty influenced the well-being of the students in addition to physical safety issues.Item Prevalence, trends and risk factors of breast cancer Mortality in Namibia: 2000-2015(University of Namibia, 2017) Pazvakawambwa, Lillian; Embula, S.P.The objectives of the study were to establish prevalence, trends and risk factors for breast cancer survival in Namibia. Secondary data was available from the Namibia Cancer Association Registry for breast, cervical and prostate cancer from the year 2000 to 2015. Patient survival was measured by age at death and the event variable was whether the patient was still alive or dead. Covariates included sex, ethnicity, and region. Descriptive summary statistics in form of tables, charts and graphs were used to profile the background characteristics of the patients. Kaplan-Meier curves were constructed and the Cox proportional hazards model was used to establish the determinants of survival among cancer patients. Results showed that breast cancer survival was influenced by age, region and ethnicity. Policy efforts should focus on the whites, basters and Herero speaking groups. Khomas region had the highest percentage of cancer cases and this calls for further research on the causes.Item Utilization of water quality index (WQI) in water quality assessment of groundwater in Agbor metropolis, Delta State Nigeria(University of Namibia, 2017) Oboh, I.P.; Egun, N.K.A water quality index provides a single number that expresses the overall quality at a certain location and time based on several water parameters. The objective of the study was to calculate the Water Quality Index (WQI) of groundwater in Agbor metropolis, Delta State Nigeria in order to assess its suitability for drinking and domestic purposes. WQI was determined on the basis of various physico-chemical parameters namely pH, Electrical conductivity (EC), Turbidity, Total suspended Solids (TSS), Total Dissolved Solids (TDS), Dissolved Oxygen (DO), Biochemical Oxygen Demand (BOD), Sulphate, Nitrate, Phosphate, Chloride, Copper, Lead, Iron, Zinc and Cadmium. The calculation of the WQI was done using weighted arithmetic index method. The WQI was found to be 45.46 indicating that the groundwater in the study area is of good quality in its un- treated state quality and therefore safe for human consumption and domestic purposes.Item Diet of Barn owls (Tytoalba) in Katima Mulilo, Zambezi region, Namibia(University of Namibia, 2017) Nghipangelua, P.N.; Lukubwe, Michael SinvulaThe diet of barn owls (tytoalba) was studied at three active roosting sites in order to understand their feeding ecology throughout various phases of the annual cycle. We conducted weekly field trips between June and October 2016. During that period a total of 516 pellets were collected during the wet (353) and dry season (163). Furthermore, this study has resulted in the first-ever documentation on the diet of barn owl in Katima Mulilo in the Zambezi region of north eastern Namibia. bones and skulls were extracted from dissected pellets and identified to taxonomic level based on cranial structure and bdirect comparison to reference specimens collected from shamvura, Kavango east region by kopij (2013).small mammals were the main prey in both seasons (86.3% in the wet season and 94% in the dry season) followed by arthropods in the wet season with 12.8% and 2% in the dry season, while birds contributed 0.5%in the wet season and 4%in the dry season. Results of this study point to the importance of basic field studies to understand the needs of a particular species as well as the community that supports it.Item The Savannas: An integrated synthesis of three major competing paradigms(University of Namibia, 2017) Nakanyala, Jesaya; Kosmas, S.; Hipondoka, MartinThe coexistence between trees and grasses in the savannas is a contentious issue. Al- though necessary scientific efforts have been done, unfortunately such efforts have given rise to contrasting theories and models. This review provides a synthesis of these theories how they influenced our understanding of the savannas over time. The review found that while the equilibrium theory predicts savannas as stable ecosystems regulated by natural mechanisms such as root niche partitioning, such ideas have been disputed in favour of non-equilibrium framework. The latter suggests that savannas are unstable ecosystems largely regulated by stochastic dynamics such as inter annual rainfall variations and episodic environmental shocks such as fire and overgrazing which result in an ecosystem oscillation between grass dominated and woody dominated phases in time and space. On the other hand the disequilibrium paradigm argues that savannas are unnatural ecosystems formed as a result of anthropogenic disturbances such as fire and grazing that buffer the ecosystem from complete domination by either trees or grasses. This review demonstrates that the savannas still lack a unifying theoretical framework. The current one is characterized by conflicting, contradictory, diverging ideas. Such revelations call for a need to develop a unifying theoretical framework for the savannas.Item Bacteriological analysis of household water from hand-dug wells in the Cuvelai-Etosha basin of Namibia(University of Namibia, 2017) McBenedict, Billy M.; Wanke, Heike; Hang' ombe, B.M.; Chimwamurombe, Percy M.Communities in Oshikoto, Omusati, Ohangwena and Oshana regions of Namibia widely utilize the Cuvelai-Etosha Basin by constructing hand-dug wells to provide water to sustain agriculture and households. Since these regions lack a developed water pipeline system and deeper ground water maybe saline in large parts of the Basin, people rely on domestic water supply from private hand-dug wells which are near their houses for convenience and preference. However, the microbial water quality and safety of hand-dug wells being utilized for household consumption in the Cuvelai-Etosha Basin is unknown and this is undesirable since water is a habitat for some pathogenic microorganisms there by posing a health risk. Thus, a bacteriological water quality study that focuses on the identification of microbial contaminants was conducted on 25 wells in the Cuvelai-Etosha Basin of Northern Namibia during two sampling campaigns. Molecular methods indicated the presence of Bacillus aerophilus, Bacillus amyloliquefaciens, Bacillus aquimaris, Bacillus aryabhattai, Bacillus cereus, Bacillus licheniformis, Bacillus pumilus, Bacillus safensis, Bacillus samanii, Bacillussp.M37,Bacillussp. M26, Bacillus stratophericus, Bacillus subtilis, Pseudomonas mendocina, Staphylococcus haemolyticus and Streptomyces celuloflavus.Item Level of adherence to safety measures on construction sites in Abuja, Nigeria(University of Namibia, 2017) Jimoh, R.A.; Oyewobi, L.O.; Isa, R.B.; Momoh, A.S.The construction industry is known to be one of the most hazardous industries in terms of the activities on the construction site and it has poor safety records. In order to have a comprehensive understanding and gainfully benefit from safety measures on site, the causes of accidents and level of adherence to safety rules needed to be examined. Therefore, this research assessed the level of adherence to safety measures on construction sites in Abuja, Nigeria. A well-structured self-administered questionnaire survey of 140 selected firms was conducted in Abuja. Findings showed that the Personal Protective Equipment (PPE) is the most used safety measure on construction site. Using factor analysis, the causes of accidents were classified into three dimensions namely poor safety planning; poor adherence and worker attitude, while safety measures were grouped into five underlying factors: personal protective equipment; effective enforcement; safety prevention mechanism; safety arrangement and safety culture. The study concluded that there is high adherence level to safety measures by the medium and large construction firms in the study area. It is recommended that construction firms should ensure that operatives comply with the prescribed safety and health measures so as to reduce accident occurrence on construction sites.Item Analysis of the basic Ross-MacDonald Malaria model parameters(University of Namibia, 2017) Iiyambo, David S.We consider a basic finite dimensional Ross-Macdonald malaria mathematical model on interaction of the infected humans and the infected mosquitoes. We study this system for consistence of the equations to the real biomedical situation that they model. Local and global well-posedness of the system is proven and the analysis of the equilibrium points is carried out. Numerical analysis show that mathematical analysis is very powerful for understanding such systems.Item An investigation into the antibacterial activity of pigmented secondary metabolites isolated from streptomyces from Windhoek soil(University of Namibia, 2017) Iikasha, Albertina M.; Eiman, H.; Mumbengegwi, Davis R.There is an increase in mortality from infectious diseases due to an increase in antibiotic resistance worldwide. Hence, his study aimed at investigating the antibacterial activity of Streptomyces that produces pigmented secondary metabolites .The soil samples were collected from 3 different sites in Windhoek. Streptomyces were isolated on starch case in agar. Biochemical and physiological tests were used to identify Streptomyces species. Case in slantagar method was used for preliminary anti-bacterial test. Chloroform and n-Hexane were used to extract secondary metabolites by solvent-liquid extraction method.Thin layer chromatography plates were used for antibacterial activity of the isolated secondary tabolites.Minimum inhibitory concentration of isolated secondary metabolites was determined by the broth dilution method at concentrations ranging from 50to1.5 μg/ml. Six out of nine Streptomyces isolates showed antibacterial activity against at least one of three test bacteria. Streptomyces isolate 1exhibited potentactivityof19.5mm ± 0.056 against M. avium. Different pigmented secondary metabolites were produced and showed antibacterial activity against at least against one of three test organism. Streptomyces isolate 4 and 6 showed the lowest minimum inhibitory concentration of 6.25 μg/ml against M. avium and E. faecialis. The results showed that Windhoek soil contain antibiotic producing Streptomyces.Item Potential application of the Moringa species as natural supplements in Namibia: A review(University of Namibia, 2017) Huber, Sharon; Huber, Thomas J.; Ananias, Natalia K.; Knott, Michael G.The members of the Moringaceae tree family show promise as good dietary sources of essential nutrients. Moringa oleifera is the most researched species of Moringa trees and has gained much recognition for its exceptionally high nutritional value. It is particularly rich in minerals, such as calcium and iron which are essential for growth and development. Indigenous to Namibia, Moringa ovalifolia is one of the under-recognized species which could potentially carry the same nutritional importance as M. oleifera. Malnutrition remains a major public health problem in Namibia. On average27%of the Namibian population lives below the poverty line and are at risk of food in security. In times of persistent drought, micro nutrient malnutrition may become a wide spread occurrence. This paper explores the health benefits of nutrients found in M. oleifera and M. ovalifolia, with particular focus on their potential to alleviate nutrient deficiencies in Namibia.Item Nitrate and bacteriological assessment of groundwater in Omaheke region, Namibia(University of Namibia, 2017) Claasen, Tiffany; Lewis, Earl W.In Namibia, a large percentage of the population uses water from sources such as rivers, wells and boreholes. The quality and safety of such water sources is generally considered poor, and therefore is a potential health hazard. Groundwater in boreholes does not go through a treatment process and therefore the cleanliness of water is a major concern. The main objectives of the study were to analyze groundwater for nitrate and bacteriological content, i.e. total coliforms, faecal coliforms, Enterococci and E.coli, as well as evaluate sanitation practices. The study area included 8 farms on the C20 road to Aranos, Omaheke region. The nitrate and bacteriological results were compared with the guidelines for safe drinking water used by NamWater and World Health Organization (WHO). The results showed that Groot Ums was the only farm having water unfit for human consumption (Grade D), Cristiana 1 had water that had a moderate risk factor (Grade C) to human health, while the rest of the 6 farms had very safe drinking water (Grade A and B). Based on the findings, short and long-term recommendations on sanitation practices were made to help farmers with the current water situation.Item Relative importance analysis of the factors influencing maize productivity at Olushandja and Etunda irrigation Schemes of Namibia: A secondary analysis of data from farm household survey(University of Namibia, 2017) Charamba, Vonai; Thomas, Benisiu; Charamba, BeatriceThe main objective of this study was to apply relative importance analysis to determine the main factors that affect maize productivity for smallholder maize farmers in the Olushandja Dam and Etunda Irrigation Schemes, north-central Namibia. According to the analysis the key determinants were labour, consultation with extension service providers, land under maize production, the type of seeds used (local or hybrid), access to credit facilities, the experience in horticultural farming. The results singled out labour as the most important factor in maize production, accounting for 16.4% of the farm level variations in technical efficiencies. Technical efficiency gains as the size of land increases. This probably means that those farmers with small plots applied too much of inputs with respect to the size of their land. Farmers who consult extension services and those trained in good horticultural practices were more technically efficient and credit facilities should be availed to farmers so that they can access farm inputs in time to boost productivity.