Natural & Applied Sciences

Research Papers/Topics Natural & Applied Sciences

Effect Of Silver Doping On The Optical And Photocatalytic Properties Of Zinc Oxide Thin Films

Abstract To study the optical and photocatalytic properties of zinc oxide (ZnO or zincite), thin films doped with metallic silver-nanoparticles (Ag-NPs), with various amounts of Ag (20 mol% ≤ n ≤ 80 mol%), were fabricated on a quartz glass substrate at 600°C in air using the molecular precursor method (MPM). The fabricated thin films were analysed and X-ray diffraction (XRD) patterns of Ag nanoparticles, zinc oxide, and composite AgNP/ZnO films were measured using an X-ray diffractomete...

Assessment Of The Prevalence Of Pathogenic Bacteria In Street Vended Ready-To-Eat Meats In Windhoek, Namibia

ABSTRACT While street vended ready-to-eat meats provide a source of readily available and nutritious meals for the consumers, there is a concern for their safety and microbiological quality. The prevalence of E. coli, Salmonella, Shigella, L. monocytogenes, S. aureus and Enterobacteriaceae was assessed in a total of 96 street vended ready-to-eat meat samples collected from Windhoek locations, namely, Katutura, Prosperita and Dorado Park. Selective media was used to assess aerobic plate count...

The q-Analogues of Some Inequalities for the Digamma Function.

Abstract In this paper, we present the q-analogues of some inequalities concerning the digamma function.

Complementary Power Series Exponentiated Nadarajah-Haghighi Distribution

ABSTRACT   A new class of distributions, called complementary power series exponentiated Nadarajah-Haghighi distribution was developed in this study by compounding the exponentiated Nadarajah-Haghighi distribution with zero truncated power series distributions. The new class of distributions were developed using the concepts of latent complementary risk scenario, in which the lifetime associated with a particular risk is not observable; rather we observe only the maximum lifetime value amon...

Pub Network 95 PAGES (14021 WORDS) Statistics Thesis
The Distribution, Genetic Diversity And Uses Of Ganoderma Mushrooms In Oshana And Ohangwena Regions Of Northern Namibia

ABSTRACT Basidiomycetous fungi, including Ganoderma lucidum, have a variety of uses such as providing nutrition and as medical remedies. The mushroom G. lucidum has been used for a long time to cure liver problems, heart condition, asthma, cancer high blood pressure and arthritis. Recently, it has been associated with boosting immune systems in HIV infected persons. It is for these reasons that the mushroom has attracted a lot of attention leading to proposals of cultivating to increase supp...

Types Of Strategies Used To Solve Algebraic Word Problems By Grade 12 Ordinary Level Mathematics Learners Of Kavango East Region Of Namibia

ABSTRACT This study investigated the types of strategies used by Grade 12 ordinary level mathematics learners to solve algebraic word problems in Namibian settings in the Kavango East Educational Region. The study used a descriptive qualitative research approach in which the researcher identified the strategies used by Grade 12 learners to solve algebraic word problems. The study used observations and focus group discussions as methods for data collection. The researcher independently conduc...

A Copula Approach To Sample Selection Modeling Of Treatment Adherence And Viral Suppression Among HIV Patients On Antiretroviral Therapy (ART) In Namibia

ABSTRACT Namibia has a generalized human immunodeficiency virus (HIV) epidemic, with HIV mainly transmitted through heterosexual transmission. Although the number of people receiving ART has increased, the achievement of the 90-90-90 strategy on testing, treatment and suppression has not been evaluated. Moreover, examining factors associated with treatment adherence and viral suppression will assist in designing appropriate accelerated interventions. However, modelling treatment adherence an...

Electronic Commerce In Namibia: Its Growth, Present Status And Potential

Abstract Wide varieties of trading methods are rapidly being replaced by the use of computers and communications networks the world over. This new concept of trading is known as Electronic Commerce (e-commerce). Great potentials exist for saving costs and improving services by utilizing this technology. Examples of phenomenal successes and staggering cost savings are just too many. Profits in millions of dollars are mentioned with ease, as a result of applying e-commerce. It is apparent that...

An Investigative Study In The Utilisation And Promotion Of Electronic Resources In Government Libraries: A Case Of Namibia

ABSTRACT This research study assesses whether a lack of marketing and promotion causes a decrease in the usage of electronic resources or whether there are other prevailing factors that prevent users from using the libraries’ electronic resources. The research tried to find out what marketing and promotional techniques are employed and how the electronic resources are organised in the selected libraries. The study covered the Khomas region in Windhoek, Namibia. The principal method used to...

Magnetic Nanoparticles Modified With Moringa Seed Proteins For Water Treatment And Recovery Of Precious Metal Ions

ABSTRACT Access to clean and safe water for everyday use is needed for a healthy society. Water treatment and recovery of precious metals is a serious challenge particularly for developing countries since the current technologies are not attractive because they are often expensive and not environmentally friendly. Precious metals such as gold, palladium, and platinum are valuable and hence crucial for any economy. Coagulants used in the treatment and recovery of precious metals have setbacks...

Anticancer, Antioxidant And Antimicrobial Screening Of Extracts From Ziziphus Mucronata, Heliotropium Ciliatum And Gnidia Polycephala From The Oshikoto Region Of Namibia

ABSTRACT Plants have long been used to treat ailments such as headaches, stomach-ache, diarrhoea, tumours, wounds and sexually transmitted diseases, just to mention a few. Ziziphus mucronata, Heliotropium ciliatum and Gnidia polycephala are traditionally used to treat tumours and wound-related illnesses. Tumours and persistent wounds can be a sign of cancer. Microbial wound infections can also bring fatal consequences if unattended. This study evaluates the antioxidant, anticancer and antimi...

An Investigation Of The Strongness Property For Nearness Frames

Abstract This study will investigate the strongness property for nearness and nearness partial frames. We initially revisit the concepts of strong and totally strong nearness frame and study their closures under completion. We also explore the properties of totally strong and uniformly completely regular nearness frames, and study the relationship between them. We show that the category of totally strong nearness frames is coreflective in the category of uniformly completely regular nearness...

Characterization Of Starch Accumulation In Storage Root Of Marama (Tylosema Esculentum)

ABSTRACT Starch is of substantial industrial significance for food and non-food uses. Plant roots and tubers such as potato and cassava are rich in starch and they are among the sources of starch for food consumption and industrial use. With climatic changes it is important to find crops that can be used as food and will still be able to survive the arid conditions. Marama is a plant that grows in the arid Namibian conditions, that bears a storage root that it is underutilized and has a pote...

The Occurrence And Distribution Of Mercury And Co-Occuring Metals In Selected Namibian Areas Affected By Industrial And Mining Activities

Abstract The occurrence and distribution of mercury (Hg) and other co-occurring heavy metals in the mining towns of Berg Aukas and Tsumeb in northern Namibia were studied Different forms of Hg and other heavy metals were characterized in soils, water and plants collected in these areas. Total metal concentration was determined using ICP–OES and total Hg was determined using the DMA 80 mercury analyser. Fractionation of Hg and other heavy metals were determined by performing a four step seq...

Antibacterial, Antioxidant And Phytochemical Investigation Of Acacia Arenaria, Aloe Esculenta, And Pechuel-Loeschea Leubnitziae

ABSTRACT Natural products present in medicinal plants are an important source of therapeutic agents and many research groups are currently screening different biological activities of plants. This study aimed to investigate the antibacterial, antioxidant properties and phytochemical analysis of Acacia arenaria (Fabaceae), Aloe esculenta (Alliaceae) and Pechuel-Loeschea leubnitziae (Asteraceae) that are used in traditional settings. The antimicrobial activity of the methanol-dichloromethane (...


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