Volume 8 (ISTJN)

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Influence of resting period on fruits and secondary tubers of Harpagophytum procumbens in Namibia
(University of Namibia, 2016) Mowa, Edgar; Maas, Erika
Harpagophytum procumbens, the devil’s claw, is a plant with medicinal values in Namibia, leading to high demands, and resulting in unsustainable harvesting techniques by locals. The most commonly practiced harvesting period is 2 years, mostly dictated by the need to make as much money as possible. A study was undertaken to investigate the effect of extending the current 2 year harvesting period to 5 years on secondary tuber and fruit production. Two experimental plots at two sites (Vergenoeg and Tjaka Ben Hur) were explored. The first plot had plants harvested every 2 years and another only after 5 years. Between sites and within sites differences in means were analyzed using a t-test at _ = 0.05. Results established that there was no difference in fruit production between the 2 groups at Vergenoeg (p = 0.375) and Ben Hur (p = 0.131). However, between sites variability in number of secondary tubers was Observed (p = 0.014). Particularly, at Vergenoeg, the number of secondary tubers pro duced after 5 years, were abundant (p = 0.003). In addition, the harvest at Vergenoeg showed a difference in weight of secondary tubers between the 2 groups (p = 0.006). Within Ben Hur, there was no difference (p = 0.928) between the numbers of secondary Tubers produced at 2 years and at 5 years. A holistic management approach (rotational harvesting) is recommended for to harvest every 5 years to maximize benefit and sustain the species.
The role of the National Botanic Garden of Namibia in plant species conservation
(University of Namibia, 2016) Kangombe, Fransiska; Moses, M.N.; Kwembeya, E.G.
This study was aimed at determining and comparing plant species diversity, species Composition and species richness in the National Botanic Garden and AloeTrail areas in Windhoek, Namibia. Floristic data were collected following standard random plot sampling procedure, where1m × 1m plots were nested in the 20m x 20m plots to measure herbaceous and woody plant species respectively. A total of 50 and 40 plots were sampled at the Botanic Garden and Aloe Trail areas respectively. The Shannon-Wiener diversity index was used to compute the species diversity of each plot sampled in each area. The Shapiro-Wilk test was used to test the data for normality. The Jaccard index of similarity revealed a 64% percentage similarity in species composition Between the two sites. However, there was no significant difference in the herbaceous Cover (Mann-Whitneystatistic, Z = −1.314,p = 0.189) between the two areas. The Botanic Garden showed a significantly higher species richness than the AloeTrail (ttest, p= 0.000). In addition, the Botanic Garden was found to be significantly more diverse (Mann-Whitneystatistic, U=478, p=0.000) than the AloeTrail because it is a protected area that is fenced and with minimal disturbances. The higher species diversity in the National Botanic Garden is attributable to the role of these living collections in the conservation of plant species.
An assessment of the prevalence and treatment outcomes of multiple antibiotic prescribing vis-`a-vis the appropriateness of antibiotic prescriptions in the empirical treatment of infections: Across-sectional study from Lesotho
(University of Namibia, 2016) Adorka, Matthias; Mitonga, Kabwebwe H.; Allen, Kirk
Purpose: The study had the objective of evaluating the prevalence and effectiveness of healthcare providers use of multiple antibiotics in the empiric treatment of infections. Methods: Three hundred and seven (307) antibiotic prescriptions from inpatient departments of five selected hospitals in Lesotho were assessed for their appropriateness. Antibiotic treatment success rates among patient groups and subgroups treated with antibiotic prescription categories considered appropriate and in appropriate and with specific numbers of antibiotics were determined. Correlations or associations of numbers of antibiotics per prescription and relevant variables were determined and used to evaluate the effects of multiple antibiotic prescribing on treatment outcomes. Results: Single antibiotics were almost prescribed for clinical conditions where prescribes had not absolutely identified bacteria pathogens as aetiologies of treated infections. Greater numbers of prescribed antibiotics were associated with inappropriate use of the agents in the empiric treatment of infections. Appropriateness rather than numbers of prescribed antibiotics correlated positively with treatment outcomes. Conclusion: no categorical relationship appears to exist between the number of antibiotics prescribed and treatment outcome. Prescribing higher numbers of antibiotics did not produce higher favorable treatment outcomes as compared with prescribing antibiotics appropriately.
Effect of pre-cooking pearl millet (Pennisetum glaucum) flour on the reduction of dregs in oshikundu
(University of Namibia, 2016) Hepute, N.R.; Embashu, Werner; Cheikhyoussef, Ahmad; Nantanga, Komeine K.
Oshikundu or ontaku is a low-or non-alcoholic fermented drink commonly produced in over half of Namibian households on daily basis. It is prepared using water, pearl millet (Pennisetum glaucum) flour and sorghum (Sorghumbicolor) malt flour. Like many African fermented drinks, oshikundu is a dynamic drink with live fermenting microorganisms that can lead to spoil age of the drink. Thus, the optimal shelf life is not known. The amount and quality of ingredients and conditions of processing are not standardised. Oshikundu has a lot of insoluble solids which tend to settle and form a sediment (dregs) at the bottom. To reduce the amount of dregs, this study used smaller amounts of sorghum malt and pearl millet flour that produced the same volume of oshikundu, as that produced using traditional amounts. The duration of heating pearl millet flour adjunct was also varied to improve the solubilisation of starch but not to change the consistency of oshikundu from the way it is prepared traditionally in households. The amount of total solids in oshikundu prepared in this study was significantly lower from those of common household-made oshikundu.
Risk factors for the transmission of brucellosis on mixed sheep and springbok (Antidorcas marsupialis) farms in the //Kharas region
(University of Namibia, 2016) Madzingira, Oscar; McCrindle, C.M.E.
A questionnaire survey was carried out on eleven randomly selected farms in the //Kharas region rearing both sheep and springbok to find out the factors which may favor the transmission of brucellosis in either direction. Sheep (69%) and springbok (Antidorcas marsupialis) (21%) were the main species on the farms, with varying numbers of cattle, goats, Oryx (Oryx gazelle) and kudu (Tragelaphus strepsiceros). The introduction of replacement rams and ewes of unknown brucellosis status on the farms; the absence of vaccination of sheep against Brucella melitensis (n=11); the close interaction be- tween sheep and springbok throughout the year (n=8) at watering points and in areas with good grazing (n=3) were identified as factors that may favour the introduction and cross-transmission of brucellosis between the two species. The study identified that farm workers on three farms were at risk of brucellosis because they consumed raw sheep milk.
Effects of varying acidic levels on dissolution, strength, organic content ands urface texture of Pacific oysters (Crassostrea gigas) shells
(University of Namibia, 2016) Omoregie, Edosa; Garises, G.; Liswaniso, G.; Iitembu, J.
Marine coastal organisms are exposed to periodic fluctuations in sea water pH driven By biological carbon dioxide (CO2) production which may in the future be further exacerbated by the ocean acidification associated with the global rise in CO2. There is widespread concern that these changes have direct impact on coastal organisms and alter the habitats severely. However, little or no attention has been given to the effects of the anticipated decrease in coastal pH on farmed oysters within the Namibian coastal waters. In this investigation, shells of the Pacific oysters, Crassostrea gigas were exposed to varying acidic levels under laboratory conditions; pH level 6.5 represented extreme hypercarpnia condition, 7.0 and 7.5 representing future predicted coastal pH levels. Shell dissolution rate, strength, organic content and surface texture were assessed after a two-week exposure period. Significant loss (p < 0.05) in weight and diameter were observed in shells exposed to 6.5,7.0 and 7.5 pH levels compared to shells in the control groups (pH8.1-8.2). With regard to organic content of the shell, significant reduction (p < 0.05) was only observed in shells exposed to 6.5 and 7.0 pH levels. Microscopic examination of the shell surface revealed reduced nacreous layer while the organic layer of the shells was sheared in acidic conditions. Visual inspection of the nacre region of shells exposed to 6.5 ,7.0 and 7.5 pH showed straight edged tablets, with the nacre regions characterised by sparse with irregular shaped tablets within a reduced organic matrix. Ocean acidification can impact potential changes in morphometry and shell structure of pacific oysters during culture.
An examination of the chemical structures and in vitro cytotoxic bioactivity of halomon related secondary metabolites from Portieria hornemannii found worldwide
(2016) Knott, Michael G.
An examination of the chemical structures and in vitro cytotoxic bioactivity of halo-genated monoterpenes isolated from Portieria hornemannii worldwide is presented here for the first time. It is anticipated that this analysis will be of valuable to the natural product chemist working in the field of drug discovery with reference to the rapid identification and possible characterisation of halogenated monoterpene secondary metabolites which demonstrate in vitro cytotoxic bioactivity.
A brief overview about models and methods to calculate the tilt angle and orientation of photovoltaic panels to maximize power generation
(University of Namibia, 2016) Torres-Perez, Mirelys; Rodriguez-Puente, Rafael
Photovoltaic systems are presented as an alternative energy for a sustainable development that can satisfy global energy requirements and provide electricity in remote locations, usually in accessible and away from the electrical network. An essential step in the installation of a photovoltaic solar module is to determine the tilt angle and orientation with respect to the horizontal plane, because an incorrect orientation and inclination can decrease the production capacity and lifetime of a photovoltaic module. The optimum angle for collector’s surfaces of a solar system is determined by many factors such as the incident radiation on the place of the installation and the solar sky, where the shadow of objects that cannot be eliminated like buildings, mountains and others must be taking into account. Based on a literature review of the models and methods more employees worldwide, we provide a brief overview of models and methods to calculate the angle and orientation of a panel in order to maximize power generation.
An activity theory analysis of factorsm influencing information security practices in software organisations
(University of Namibia, 2016) Iyawa, Gloria E.; Mufeti, Tulimeveva K.
Information is an asset to any organisation. As a result, different organisations strive to ensure that information is well protected. This has led to organisations creating information security policies Despite this approach, employees play a vital role to ensure that these policies are implemented. Information security has been studied in different contexts. However, in the existing literature, there is limited research which investigates the factors that influence information security practices in the context of software organisations. Similar to other business contexts, information is an important tool within software organisations. The purpose of this study was to investigate the factors that influence information security practices in software organisations using a Namibian software organisation as a case study. The use of Activity Theory as a lens helped to investigate the factors that influence information security practices in software organisations which are often overlooked. From the analysis of the findings, it is evident that factor such as employee structure, work context, information sensitivity, reputation, responsibility, accountability and policies influence information security practices in software organisations. The findings revealed that information security policies have to been forced at different levels and units in software organisations. The findings from this study may assist software organisations when implementing information security policies.

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