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Item Soil radioactivity levels and associated hazards in selected towns in uranium-rich western Namibia(University of Namibia, 2016) Shimboyo, Simon A.; Oyedele, James; Sitoka, S.S.Soil samples from three major towns and a holiday settlement in uranium-rich western Namibia have been analysed using a HPGe detector for radioactivity due to 238U, 232Th and 40K. The average activity concentrations of the radionuclides in the towns and settlement vary from a low of 18.6 ± 4.6 to a high of 69.6 ± 26.3 Bq kg−1 for 238U, 23.8 ± 8.4 to 91.1 ± 41.0 Bq kg−1 for 232Th and 460.3 ± 76.2 to 959.5 ± 194.7 Bq kg−1 for 40K. In order to evaluate the associated health hazard, the concentrations were used to calculate the mean annual effective dose, radium equivalent activity (Raeq) and external hazard index (Hex) for the towns and settlement. The values of 0.11 mSv, 195.3 Bq kg−1 and 0.53 obtained respectively for the mean annual effective dose, Raeq and Hex are, however, below their permissible limits thus implying that radiation hazard is negligible.Item Birds of Katima Mulilo town, Zambezi region, Namibia(University of Namibia, 2016) Kopij, GrzegorzLarge river valleys are usually characterized by high level of biodiversity, avian diversity. In Namibia, two towns are located in such valleys: Rundu on Okavango and Katima Malilo on Zambezi. To date, no quantitative studies on any components of biodiversity have been conducted in those towns. In January-May 2013, a total of 36 days were spent on quantitative studies of birds in Katima Mulilo town. The line transect and territory mapping methods were used in this study. A total of 122 resident (breeding), 9 visitors and 9 Palearctic migrants were recorded. The group of dominant species was composed of the following four species: Grey-headed Sparrow, Black-eyed Bulbul, Laughing Dove, and Blue Waxbill. They comprised together 42.5% of all birds. The group of subdominant species included: Rock Dove, Pied Crow, Cape Turtle-Dove, Red-eyed Dove, Southern Masked Weaver, Burchell’s Starling and Mourning Dove. Together they comprised 18.7%. The remaining 112 species comprised 38.8%. The most numerous feeding guilds were granivores (51.3%), frugivores and insectivores (each with c. 20%). Most birds (61.3%) nested in trees and shrubs. Katima Mulilo is probably the only town in whole southern Africa, where all four Streptopelia-doves are common species: Laughing, Cape Turtle, Red-eyed, and Mourning Dove. The only sparrow, which occurs in Katima Mulilo, is the Grey-headed Sparrow. Of special interest is the occurrence of dozen or so species which do not occur in other towns in Namibia, such as African Fish Eagle, Broad-billed Roller, Schalow’s Lorie, Trumpeter Hornbill, among others.Item The isolation, structural determination and bioactivity of 1E,3R,4S,5E,7Z-1-bromo 3,4,8-trichloro-7- (dichloromethyl)-3-methylocta-1,5,7-triene from a Namibian Plocamium species(University of Namibia, 2016) Knott, Michael G.; Kapewangolo, Petrina T.; Louw, Stefan; Brand, J.; Kandjengo, Lineekela; Ishola, AnthonyA known compound namely 1E,3R,4S,5E,7Z-1-bromo-3,4,8-trichloro-7- (dichloromethyl)-3-methylocta-1,5,7-triene was isolated from a Namibian Plocamium species for the first time and characterized by means of one and two dimensional Nuclear Magnetic Resonance (NMR) spectroscopic data and Mass Spectrometry (MS) analysis. The compound exhibited minimal inhibition against HIV-1 reverse transcriptase, with a 50% inhibitory concentration of > 1000μM. However, literature reviews indicate that this compound has good cytotoxic in vitro effects.Item Social engineering and the structure activity relationships (SAR’s) of selected mind-altering compounds such as tryptamine and phenylethylamine derivatives(University of Namibia, 2016) Knott, Harriet M.The chemistry of tryptamines and phenylethylamines as both neurotransmitters and as potential agents for social engineering forms a captivating area between chemistry and neuroscience. This article highlights several drugs including phenylethylamine related derivatives such as propranolol, modafinil, methylphenidate, lamotrigine and oxytocin; as well as tryptamine derivatives such as lysergic acid diethylamide and melatonin and investigates the use of these compounds or their derivatives as potential social engineering agents.Item An attempt at modelling the diets of two sympatric species of hake (Merluccius capensis and Merluccius paradoxus) off the coast of Namibia: Isotope mixing model approach(University of Namibia, 2016) Iitembu, Johannes A.Two species of hake, Merluccius capensis and Merluccius paradoxus, are the most important secondary consumers in the Benguela current ecosystem. To better understand hake diets in the northern Benguela (Namibia), the stable carbon (13C) and nitrogen (15N) isotope ratios of their muscles, and that of their prey (Hake, n = 115 and prey, n=299) were analysed. Results indicated that their diets were dominated by Plesionika martia, Chlorophthamus agazizi, Myctophids and Euphausiids. The highest contributor to the diet of M. paradoxus varied with length, while the diet of M. capensis was dominated by myctophids at all length classes. Cannibalism accounted for less than 6% and less than 4% in the diets of M. capensis and M. paradoxus respectively. Isotope based estimates of prey dietary contributions differed from that of previous gut content analyses. Overall, the results support the hypothesis that the two species have similar diets. Application of a Bayesian mixing isotope model can be improved to allow for improved hake consumption (i.e. annual) estimates to be made.Item Isolation and Genus identification of bacteria from urine contaminated soils of Windhoek(University of Namibia, 2016) Haindongo, Erastus H.; Bock, Ronnie A.; Nafuka, Sylvia N.; Mumbengegwi, Davis R.Public urination is a common sight in the vicinity of drinking establishments in Katutura, as well as other open spaces around Windhoek. A study was conducted to determine if there was a shift in the balance of the microflora in urine contaminated soils. It was hypothesized that, given soils from the same geographic region but under distinct urine conditions, the identity and counts of the pathogenic and actinobacteria communities would vary. For the purpose of this study, pathogenic microorganisms were limited to those known to cause infections of the urinary tract. Soil samples from 4 contaminated locations (Ara-Dorado, Hakahana, Eveline and Greenwell Matongo suburbs) and controls were qualitatively tested for urease activity. Selective media was used for the isolation and enumeration of pathogenic and beneficial actinobacterial colonies. Dorado showed the greatest extend of urease activity>>>Hakahana and Eveline>>Green well matongo. There is a significant difference between the colony counts at a contaminated and non-contaminated (control) site, p = 0.019(= 0.05). The results indicated that public urination introduces pathogenic bacteria, causing a shift in the balance of the normal flora.Item Trophic relationships of three deep-sea crustacean species (Aristeus varidens, Plesionika martia and Funchalia woodwardi) off Namibia(University of Namibia, 2015) Endjambi, Tobias; Iitembu, Johannes A.; Nashima, Festus P.Trophic ecology of deep-sea crustaceans in the marine waters off Namibia is not well understood, although they form part of diets of important commercial species off Namibia. Study of their trophic relationships enhances our understating of the functioning of marine food webs and avail information needed for consideration of trophic interaction in fisheries management decisions. This study aimed at investigating the trophic relationships of striped red shrimp (Aristeus varidens), golden shrimp (Plesionika martia) and Woodward’s pelagic shrimp (Funchalia woodwardi) using stable isotope (nitrogen 15N) measurements of their muscle tissues. Samples were collected during the 2010 annual hake biomass survey off Namibia. Significant differences were observed in the mean trophic levels and nitrogen (15) measurements of the three species. Funchalia woodwardi showed a negative linear relationship between size and 15 and between depth and 15. Aristeus varidens and P. martia showed no significant linear relationship between 15 and depth or size. This work is the first to examine trophic relationships of the three deep sea crustaceans in the Northern Benguela current ecosystem using stable isotope analysis.Item The road safety in Namibia: Focus on road traffic accidents(University of Namibia, 2016) Amweelo, MosesThis paper discusses road traffic accidents in Namibia. The occurrence of road accidents and the resulting fatalities and injuries are of great concern to the government of the Republic of Namibia. This is confirmed by available vehicle collision rate and overload statistics as well as independent studies of the municipal and Namibia traffic police. The paper also discusses the new road traffic and transport act, which is envisaged to be implemented in due course. This will improve the control of vehicle roadworthiness testing and registration, licensing of drivers, rules of the road and traffic law enforcement. The so-called ”human factor” plays a role in the majority of vehicle accidents. Cognitive psychology provides more detailed information on human factors. It explains theoretical concepts and principles on how the mind works. It has also been said that cars do not cause accidents, people do. For this reason a ”technical” and ”legal” approach alone are not regarded as sufficient to improve the road traffic safety situation in Namibia. Additional actions directed at applied research education of the public and in general the engendering of a road traffic safety ethic is necessary.