Biological Science Research Papers/Topics

Urban Agriculture Projects: Case Studies In The Cities Of Windhoek, Namibia And Berlin, Germany

Abstract The protection of biodiversity within cities is becoming more crucial by the increasing number of people living in urban areas. Within this study urban agriculture projects (UAP) are analysed according to their ability to face this challenge. It was uncertain if UAP exist in Windhoek, this study proofs that they do. This research was undertaken in two cities: Windhoek, Namibia and Berlin, Germany under special consideration of two main research questions: (1) Does UAP have the abili...

Detection Of Leptospira And Seasonal Prevalence Of Fleas Collected From Small Mammals In Mukwe Constituency, Kavango East Region Of Namibia

Abstract Biotic and abiotic factors can alter the abundance and community composition of mammals and in turn that of associated parasites. The aim of the study was to measure the impact of climatic variables (temperature and relative humidity) on mammal populations and on the population dynamics of associated micro- and ecto-parasites. For this, the current study described prevalence and diversity of pathogenic Leptospira, the etiological agent of leptospirosis, and fleas, arthropod vectors ...

Phytochemical Screening And Antibacterial Testing Of Selected Namibian Medicinal Plants Against Laboratory And Clinical Bacteria That Cause Diarrhoea

ABSTRACT Medicinal plants are rich in a wide variety of bioactive compounds associated with various ailments; including antibacterial activity and some of them have been used worldwide in traditional settings to treat diarrheal diseases. However evidence on safety and efficacy of some of these traditional medicinal plants is lacking, preventing their mainstream use. This study aimed at determining the antibacterial activity of Boscia albitrunca, Ziziphus mucronata, Combretum apiculatum, Sola...

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...

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...

Evaluation Of Selected Namibian Ethno-Medicinal Plants For Anti-HIV Properties

ABSTRACT Namibian ethno-medicinal plants have not yet been evaluated for their efficacy in inhibiting the activities of Human Immunodeficiency Virus (HIV) reverse transcriptase (RT) and their toxicological effects to mammalian cells have not yet been reported. Hence the aims of this study were: (1) to evaluate selected Namibian plants for their biological activities against RT; (2) to evaluate their toxicity to mammalian cells, and (3) to isolate and characterize the active compounds from se...

Bacteriological Quality And Safety Of Raw Beef From Selected Outlets In Windhoek (Namibia)

ABSTRACT Inappropriate slaughtering and retail operations can compromise food safety specifically in densely populated areas like informal markets. The bacteriological quality and prevalence of Salmonella spp. and Escherichia coli O157:H7 on beef samples from the three different outlets (supermarket, butchery and open market) were assessed to determine their safety for human consumption. A total of 138 of beef samples were collected at random from three different outlets. The bacteriological...

Challenges Affecting Grade 12 Learners’ Academic Examination Performance In Namibia Senior Secondary Certificate Ordinary Level Biology In The //Kharas Region, Namibia

ABSTRACT The main purpose of this study was to investigate the challenges affecting Grade 12 learners’ academic performance in Namibia Senior Secondary Certificate Ordinary level (NSSCO) Biology in the //Kharas Region, Namibia. The study addressed three research questions. Two categories of sample, made up of 140 learners and 12 teachers respectively were selected using the simple random sampling method to participate in the study. Furthermore, after the preliminary analysis of the questio...

SCALE AND IMPACT OF THE ILLEGAL LEOPARD SKIN TRADE FOR TRADITIONAL USE IN SOUTHERN AFRICA

While leopards (Panthera pardus) currently occupy the most extensive geographic range of all large felids, they are also suffering the highest rate of current range loss amongst large terrestrial carnivores. This is primarily because most leopards still range outside of formally protected areas where they are exposed to the full suite of anthropogenic threats affecting carnivores including habitat loss, prey depletion, conflict with humans, and commercial harvest for body parts. The extensive...

Functional Anatomy, Osteogenesis and Bone Microstructure of the Appendicular System of African Mole-Rats (Rodentia: Ctenohystrica: Bathyergidae)

In comparison to their ecophysiological and behavioral aspects, the skeletal system of African mole-rats (Bathyergidae) has been relatively understudied. Only a few studies have assessed their skeletal system, but these have mostly focused on their cranial and dental systems, with little attention on their postcranial skeleton. This PhD thesis provides a considerable amount of information about the functional anatomy, morphological diversity and postnatal bone morphogenesis of the appendicula...

Trace metal effects on phytoplankton in subpolar seas with special emphasis on coccolithophores

Abstract Coccolithophores are a biogeochemically important phytoplankton group, fulfilling an important role in the global carbon cycle through primary production and the formation and export of calcium carbonate. Despite this biogeochemical importance, relatively little is known about their ecophysiology, for example their response to nutrient availability in terms of both macronutrient (nitrate, phosphate) and micronutrient (trace metal) or how this impacts on their competition with other p...

Interactive effects of temperature and grazing by seagrass limpets (Siphonaria compressa and Fissurella mutabilis) on seagrass (Zostera capensis)

Abstract Climate change is a reality. One of the main ecological concerns regarding climate change is the predicted increase in atmospheric and sea temperatures. The latter is expected to rise by roughly 2.5O C by the end of 2050 with dramatic impacts on marine ecosystems predicted around the world. Seagrass ecosystems are a good example of vital ecosystems that are threatened by climate change and other anthropogenic factors. A decline in global seagrass cover of 29% has been estimated over ...

Lack of polymorphism suggests a recent bottleneck of Aloidendron pillansii

Abstract The Karoo-Namib is a species rich region in which many iconic and keystone species are found, such as Aloe pillansii. The recent population history of A.pillansii is poorly understood. However the suggested climatic shifts that occurred throughout the Holocene era may have affected its distribution, demographics and gene flow. The glacial/interglacial refugia hypothesis predicts that the southernmost population served as a refuge population and that the subsequent expansion of the po...

Sexual dimorphism in the genus Leucadendron: Morphology and plant hydraulics

The genus, Leucadendron, of the Cape Proteaceae family, is made up of over 70 dioecious species that vary in their degree of sexual dimorphism. Males are generally more highly ramified (branched) with smaller leaves compared to corresponding females.  It has been hypothesised that sexual dimorphism in Leucadendrons is linked to serotiny (a fire-adapted reproductive strategy), where highly serotinous females may incur extra resource costs in order to keep their transpiring cones alive betwe...

Friend or foe? The arrival of Stator limbatus (Bruchidae) in South Africa

ABSTRACT Stator limbatus is a generalist seed-feeding beetle (Coleoptera: Bruchidae) whose natural range extends from the southern USA to Latin America. Individuals have recently been collected in the Western Cape province of South Africa in seeds of the invasive alien plant species Acacia mearnsii and A. cyclops. This study conducted a preliminary examination of its oviposition preference, and development on, a number of indigenous and invasive alien Acacia species and the invasive alien Par...


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