Doctoral

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Theoretical foundation of the KNUST Painting programme: A philosophical Inquiry and its Contextual Relevance in Ghanaian Culture
(2006-04-27) Seidou, Kari Kacha
In the few times the College of Art, Ghana has surfaced in any influential study, there has been a general silence over its intellectual legacy...
Cultural significance of Edina Asafo Company posts.
(2006-07-13) Adentwi, Samuel Bentum
This dissertation is the cultural manifestation of the technical study conducted by the researcher. The main objective of investigating whether in line with modern socio-political and socio-economic development of Edina traditional area, the Edina people has affected the relevance of Edina Asafo was critically appreciated. The research looked into how the Edina Asafo Posts have influenced the modernization and urbanization of the Edina community. It also seeks to find out how the Asafo Posts have affected the Psyche of the Edina people as well as the political, religious, social, medical, economics, entertainment and educational (moral) standard of the people. This research is therefore to help attract and promote both local and foreign tourism in the Edina traditional area, and thereby help create income for the socio-economic development of the people, Edina and Ghana.
Modelling cadmium and lead uptake from irrigation water by some vegetables through transpiration in the semi-deciduous forest zone of Ghana
(2007-08-08) Mensah, Ebenezer
Heavy metal contamination of agricultural soils is a major concern to food production all over the world. Agricultural soil heavy metal contamination is from wastewater irrigation, application of sewage and air deposition from the atmosphere and is of great importance because of its implications for human health. Systemic health problems can develop as a result of excessive accumulation of dietary heavy metals such as Cd, Pb, Ni, Cu and Cr in the human body. A study was carried out at the Kwame Nkrumah University of Science and Technology (KNUST) in Ghana using water to which Cd and Pb had been added to irrigate cabbage, carrots and lettuce. Cadmium solutions of concentrations 0, 0.05 and 0.1 mg L-1 and Pb solutions of concentrations of 0, 30 and 50 mg L-1 were prepared and used to irrigate the crops. Kinetics of Cd and Pb concentrations in irrigation water were studied by preparing a 1:1 ratio of the sandy loam soil from the experimental site and irrigation water and shaken for 8 hours. The results showed that Cd concentration stabilized within the first 1 hour and the partition coefficients (Kd) for the 0.05 and 0.1mg L-1 irrigation water concentrations were 4 and 11.5, respectively. For Pb solutions the partition coefficients (Kd) were not constant but varied with time with values ranging between 0 and 6.94 after 6 hours of shaking. Moisture content of soil is known to influence the release of metals in soil solutions, however agricultural soils are generally of low moisture content. It was found from the study that the release of metals in soils was non-linear resulting in variation in the metal distribution coefficient. Soil Ca and dissolved organic carbon (DOC) concentrations gave a better prediction of soil Cd concentration than soil solution pH. Plant and soil samples from the experimental fields were collected for laboratory analysis. The results showed a reduction in the yields of lettuce by 11 and 16% for the treatments with Cd concentrations of 0.05 and 0.1 mg Cd L-1 in irrigation water respectively, compared with yields from the control treatment (0 mg Cd L-1 in irrigation water). On the other hand, there were increases of 61 and 53%, respectively in yields of carrots irrigated with water containing 0.05 and 0.1 mg Cd L-1. Yields of crops irrigated with water containing Pb concentrations of 30 and 50 mg L-1 were reduced compared with yields from the control plots suggesting that lead has the potential to suppress yields of crops. Plant Cd and Pb concentrations increased significantly with irrigation water concentrations of Cd and Pb with p-values of <0.0001 for Cd and <0.05 for Pb. Cadmium concentrations for cabbage were between 0.09 and 1.11 mg kg-1 while carrots and lettuce had values between 0.04 and 1.0 mg kg-1 and 0.12 and 1.02 mg kg-1, respectively. Lead concentrations in cabbage were between 0.18 and 15.2 mg kg-1 while for carrots and lettuce the concentrations were between 0.43 and 6.24 mg kg-1, and 1.41 and 187 mg kg-1, respectively. The percentage of the total Cd in the soil that is considered available, based on extraction with 0.01 M CaCl2, ranged between 18.7 and 96.8% for the top 5 cm depth and between 8.5 and 89.6% for the 5-10 cm depth. The percentage of soil total Pb considered available was in the range 0.058-7.86% for the top 5 cm depth; and 0.077 - 2.78% for the 5-10 cm depth. Both soil total and available Cd and Pb decreased with depth. Free ion activities of cadmium constituting the ions absorbed by the plants were determined by prediction using Windemere Humic Aqueous Model (WHAM) VI and measurement by cadmium electrode. Inputs for WHAM VI included soil properties like organic matter content in humic and fulvic forms, Na, Mg, K, balanced cations and anions. However, lead free ion activities were determined by prediction using WHAM VI only due to lack of lead electrode. Mathematical modelling of heavy metals uptake by plants is useful for predicting the quality of crops produced for human and other animals. The models also help to predict yields of crops produced using soil or irrigation water that is contaminated by heavy metals. In plant science, modelling of solute uptake is achieved by empirical models fitted with an equation or a set of equations to data. A modified transpiration model was therefore developed based on climatic variables such as temperature, saturation vapour-pressure deficit and relative humidity that govern transpiration and used to estimate crop dry matter content and irrigation water metal concentration, Cd and Pb concentrations in the test vegetables. The estimated and measured values were compared to determine the efficiency (EF) of the developed model. For Cd, EF values ranged between 0.911 and 0.953, while for Pb, the range was 0.514-0.995. The overall results showed that the model output using transpiration pull driven by environmental factors was reliable to predict the uptake of the heavy metals.
Diversity within yeast involved in spontaneous fermentation of pito
(2007-11-11) Glover, Richard Lander Kwame
A survey was conducted in ten (10) “Dagarti pito” production sites located in nine towns within eight administrative regions of Ghana to investigate diversity within yeast varieties involved in the spontaneous fermentation of Dagarti pito. Samples of dry yeast were obtained from commercial Dagarti pito producers from Tamale and Nyankpala (Northern Region); Ayigya- Kumasi and Monaco-Kumasi (Ashanti Region); Accra (Greater- Accra Region); Cape Coast (Central Region); Takoradi (Western Region); Sunyani (Brong Ahafo Region); Ho (Volta Region) and Suhum (Eastern Region). For purposes of comparison, dry yeast was also sampled from three dolo production sites in Ouagadougou, Burkina Faso. Yeast populations ranged between 106 and 108 cfu g-1. Twenty-five yeast isolates from each site were characterized phenotypically by colony and cell morphology as well as carbohydrate assimilation profiling, using the API ID 32 C Kit (Biomerieux SA, Marcy L’Etoile, France). Ninety-nine percent (247) of the isolates showed colony and cell morphologies typical of S. cerevisiae. Of these, 72 % (179) had fifty-three carbohydrate assimilation profiles similar to S. cerevisiae (according to Vaughan-Martini and Martini, 1998) and were subsequently identified as such while 28 % (68) which had four carbohydrate assimilation profiles atypical of S. cerevisiae or any other member of the sensu stricto complex could not be identified in API galleries. Two isolates (1%) which had colony and cell morphologies atypical of S. cerevisiae, and a broad-spectrum assimilation profile, were identified as Candida kefyr. Genotyping of five randomly selected isolates from each site was carried out using the Polymerase Chain Reaction (PCR) to amplify the region spanning the two intergenic transcribed spacers (ITS) and the 5.8S ribosomal gene (ITS1-5.8S rDNA-ITS2), followed by restriction analysis (ITS-PCR+RFLP) of the product, as well as Pulsed Field Gel Electrophoresis (PFGE). The genetic analyses indicated that all of them belonged to S. cerevisiae, notwithstanding the phenotypic differences. The mitochondrial cytochrome-c oxidase II gene (COX 2) of four isolates representing the four chromosome profile groupings that emerged after PFGE, were then sequenced to confirm their close relatedness to S. cerevisiae, particularly type strain CBS1171. Two isolates randomly selected from each of the ten production sites, (one with a broad carbohydrate assimilation spectrum and the other with a narrow carbohydrate assimilation spectrum) and assessed for technological properties showed different patterns of growth and flocculation without much change in pH during fermentation, and most of them produced pito having sensory attributes which compared favorably with commercially produced pito. Pito produced with each of ten out of the twenty yeast strains from Ghana used for the earlier investigations and three from Burkina Faso was analyzed by headspace, for its aroma constituents. All ten Ghanaian isolates could form aromatic compounds representing the alcohols, esters, and ketones which are among reported typical flavor compounds of conventional beer. This study has demonstrated diversity within S. cerevisiae strains involved in fermentation of pito wort. These strains possess desirable technological properties, including sufficient growth during fermentation and efficient hydrolysis of sugars for biomass enhancement. They also demonstrated fermentation activities, particularly, ethanol production, formation of aroma compounds and metabolites, which impart appropriate sensory attributes to pito.
Technical Problems and Solutions in the Indigenous Leather Industry: Implications for Art Education in Ghana
(2008-07-12) Boahin, John Osei Bobie
Leatherwork is an art form that has a strong traditional foundation in Ghana; it is practiced in diverse forms in different areas of Ghana, particularly in the three regions in the northern part of Ghana where production is highly concentrated. The Ghana government’s desire to promote the indigenous vocations in schools has necessitated the improvement of the technologies used by indigenous leatherworkers. 21 Some pertinent problems affecting the industry were identified these are (a) Lack of simple but efficient tools and equipment for the execution of the tanning process, (b) Poor quality leather resulting in offensive odour and its susceptibility to grow moulds as a result of fungal attack, (c) Non-fast vegetable based dyes that easily fade in the presence of sunlight and also bleeds when washed, and (d) Limited colour range of red, black, white and brown. The research will lead to the following solutions to the identified problems: (a) The production of new tanning equipment comprising, tanning vessels, scudding, tumbling and cutting machines will improve the leatherwork industry. (b) That, leatherworkers will be able to produce some working tools locally. (c) That alternative local colourants can be applied on leather. (d) The offensive odour and the fungus attack on leather will be subdued. Solutions to these identified technical problems associated with traditional leatherwork techniques to make it attractive to leatherwork education in Ghana are the focus of this project. The results of the research were attained through the experimental research methods The research lead to the following solutions to the identified technical problems: (a) introduction of alternative tanning vessels that will be useful for academic and commercial purposes, and make it possible for tanning to be done indoors and outdoors; (b) Development of scudding equipment for dehairing and fleshing, the equipment makes it possible for the craftsman to do scudding in a more comfortable posture for increase in productivity; (c) Design and construction of 22 two types of leather dryers, open- dryer and electric-dryer; (d) Tumbling equipment for boarding oil into leathers and also softening leathers and fur, and (e) Thong cutter for cutting long strips of leather for thonging or weaving. The research also identified alternative colourants that are locally available for colouring leather; these are grouped into two, Dyes and Pigments. Dye; The dyes were vat dye and suede dye, these proved to be useful on leather. and the identified pigments were oil paint and acrylic which were successfully applied on leather. Starch was also mixed successfully with vat dye as pigment in colouring leather. The research also identified techniques for controlling the offensive odour associated with indigenous tanned leathers and fur, and prevents the development of moulds on them in order to promote the marketing of leather articles locally and awaken the export of leather articles which has not been very attractive due to these problems. The findings of the research will help in the promotion of leatherwork education and the indigenous leather industry in Ghana It is recommended that specially equipped studios be built in schools at all levels for the teaching of every aspect of leatherwork to sustain the manpower needs of the industry. Beside, a research Center must be established to support the industry in the areas of design, material and technological development to meet modern needs as well as boost up national development.
The Role of Art in the celebration of Asogli Yam Festival and its Significance to the Socio-Economic Development of Ghana
(2008-07-12) Gbadegbe, Richard Selase
The celebration of Asogli Yam Festival by the people of Ho, Kpenoe, Takla and Akoepe comes with the expression of joy and happiness. It is a period for social integration, display of rich culture and stock taking where artistic and economic features of the festival are displayed both knowingly and unknowingly. The study therefore sought to highlight the artistic aspects of the festival as well as its socio-economic features. This was successfully executed by giving a detailed description of the activities of the festival based on the rites and rituals performed. As a result, a framework was established which helped the researcher to classify the specific art forms used during the festival into groups and also to explore its socio-economic interests. With the historical background of the people, a comparison has been made between the Asogli Yam Festival of the past and present in which clear-cut ideas were developed for possible improvements on the festival. The study has succeeded in exposing the rich culture of the Ewes and for that matter the Asogli people to readers and at the same time exploring the economic fortunes of the festival which was facilitated by the appreciation of the arts. The Descriptive Method of research was used by the researcher to describe and interpret events. This was combined with statistics in the form of tables and figures to analyze and interpret data. Data was collected using questionnaire, observation and interview. The Stratified Random Sampling method was used to obtain the sample population for the study. The study was grouped into six chapters. Chapter one talked about the introduction. Chapter two dealt with the review of related literature, chapter three centered on the methodology for the study and chapter four consisted of the analysis and discussion of data. Chapter five included the presentation of the main findings and chapter six talked about summary, conclusion, recommendations, appendix, glossary and references.
A Human Resource Management Policy Development (Hrmpd) Framework for Large Construction Companies Operating in Ghana
(2008-07-14) Agbodjah, Lily Sena
A framework for the development of Human Resource Management (HRM) policies in large construction companies in Ghana was the main outcome of this study. Ongoing research on HRM practices of project-based organizations have been undertaken mainly in the developed world especially Europe and North America although some current research has focused on developments in the developing world. There has however been very little research on HRM policy development guides for HRM practitioners within the construction industry globally and Ghana in particular. The extent of HRM practices and policies in large construction companies operating in the country was examined. Following the literature review and field work, a Human Resource Management Policy Development (HRMPD) framework was developed to aid large construction companies to develop appropriate HRM policies to enhance their HRM function and productivity. A mixed method research approach and a cross-sectional research design were adopted. Quantitative data collected were analyzed using univariate and bivariate techniques whereas Qualitative data were analyzed using structured narrative and content analysis methods. The research concluded that, large construction companies rely on personnel management rather than HRM ideology in managing employees within their organizations. It was found that, these companies lack appropriately trained personnel to manage the HRM function hence the function is relegated to the background and is mainly reactive. In addition, these companies do not have HRM policies to guide the function as only a few have implicit ones. Companies rely on Collective Agreement and/ or Management Prerogative in managing their people. In view of the negative effects of pursuing personnel management practices, the investigation showed that, companies have realized the need for appropriate HRM policies to espouse their philosophies concerning HRM as well as improve their competitiveness in attracting and retaining the right calibre of employees and in project delivery. This study has contributed significantly to existing literature on HRM and has provided useful pointers for enhancing the HRM function within these companies. The proposed tool, the HRMPD framework, aims at assisting large construction companies operating in Ghana develop appropriate HRM policies to enhance their HRM function. A flow-chart was adopted for the framework design which is in three main stages: formulation; implementation; and evaluation. The evaluation stage of the framework feeds back into the first two stages if the policies are not satisfactory after evaluation. The framework was tested on a sample of stakeholders, via attitude testing using the Likert Scale, who agreed with the logic and content of the framework. It was further validated via review meeting and attitude testing on selected ‘Experts’ who also agreed to the logic and content of the framework with suggestions for possible improvement. Key words: Human Resource Management; Human Resource Management Policy; Policy Development Framework; Construction Industry; Ghana
The impact of poverty on the health of rural communities in Ghana: a case study of the Amansie West District, Ashanti Region
(2008-08-05) Osei-Wusu Adjei, Prince
Many rural Ghanaian communities are saddled with major social problems that undermine efforts towards rural development in the country. In the Amansie West District, poverty and ill health are major problems that militate against many households in the rural communities. However, the impact of poverty on health among households in the District has attracted little concern over the years. The survey analyses the poverty situation and how poverty impacts ill health in the rural communities in the District. Hypotheses tested were that, poverty is the root cause of poor health; and that, adequate income and knowledge ensure better health for the rural communities of the Amansie West District. Focus group discussions, participant observation, questionnaires and in-depth interviews were the methods employed for data collection from a sample of three hundred and six (306) heads of household randomly selected from deprived rural communities for a thorough analysis of the relationship between poverty and health in the District. Relevant data obtained were analyzed using both qualitative and quantitative methods. Percentage and frequency charts, cross tabulation and multivariate regression using the Statistical Package for Social Sciences (SPSS) were the methods used to analyse the data. The results from the study clearly justified the hypotheses set for the study. Poverty was found to be the major cause of poor health. Respondents with adequate income experience relatively better health conditions in the rural communities in the District. Further, majority of the low income earners within the rural communities either do not often or not at all use the very few healthcare facilities available in the District because of inability to pay for the service cost. Generally, poverty was found to have a significant influence on some of the highly prevalent diseases in the rural communities in the District which included malaria, whooping cough, skin and diarrhoeal diseases, measles and intestinal disorders. It is concluded that any strategy or recommendation aimed at tackling poverty and health decay in the rural communities in the Amansie West District needs to focus on equipping the poor households with adequate and regular income as well as adequate level of health education. These could be achieved through the introduction of mechanized farming practices, effective implementation of government’s youth employment programme (YEP), intensification of rural community health education, extension of village infrastructure projects and promotion of the national health insurance scheme. With adequate and regular income coupled with adequate health education, the poor would be able to satisfy their basic needs to improve their quality of life and health conditions very significantly. The difficulty in quantifying some of the poverty indicators such as hygiene using conventional measuring tools was an analysis problem which was corrected by the use of the qualitative approach. The study has provided a framework for the study of the linkages between poverty and health with both qualitative and quantitative methodologies which, in some cases, were often studied independent of each other. It has further provided a philosophical base for defining and measuring poverty. It is recommended that further research be directed to examine factors other than poverty which affect rural health for a holistic strategy to reduce health decay in rural Ghana. The key methodological innovations for the study included the use of both income and knowledge poverty in relation to health , the relationship established between the indirect effects of poverty and health and the use of both qualitative and quantitative techniques in analyzing poverty and health.
Aesthetic impact of Ghanaian socio-cultural practices on the environment and its protection in Ghana
(2008-08-08) Avenorgbo, Stephen Kofi
The environment and its protection are of absolute importance to the development of humanity, socially, culturally, economically and physically. However, due to inadequate aesthetic considerations of the environment, bad cultural practices, ineffective education through art, little integration of art into scientific applications and lack of pragmatic artistic policies by governments, the degradation of the environment is rapidly on the ascendancy. In view of these, this research emphasizes the need to utilize aesthetic considerations and good socio-cultural practices to protect, beautify and conserve our natural as well as the built environments that will help improve the very livelihood of mankind. By employing the qualitative methodology to address the problems identified the research shows by its analysis, presentation, arguments and suggestions that artistic attributes and acceptable cultural values are very important to Ghanaians in enhancing the beauty of the environment, as well as preserve everything that can be found in it, such as forests, rivers, mountains, buildings and so on. This dissertation, however, is a valuable source of information and it is geared towards sensitizing other researchers, stakeholders, policy-makers, institutions, environmentalists and tourism promotion managers to be fully aware of the aesthetic aspects of the environment. The dissertation is presented in seven chapters. The first chapter, being the introductory chapter, deals with the problem and its statement. Chapter Two surveys the related literature on the subject under investigation while Chapter Three deals with an in-depth discussion on the relationship between indigenous aesthetics and the environment. Chapter Four, however, highlights on the methodology employed in the execution of the research. Chapters Five and Six form the findings of the dissertation and provide vivid discussions on the state of the environment as well as its aesthetic impact. These two chapters also present the results of the research. The thesis ends with the seventh chapter which deals with the discussions, conclusions and recommendations. By these indications, this research hopes that if the suggestions and recommendations are well embraced in national policies, our eco-system could be effectively protected from further degradation.
Ghanaian jewellery industry: its problems and solutions
(2008-08-10) Kotoku, Worlanyoh
Many developing countries including Ghana possess significant deposits of precious and non-precious metals, materials, and stones, but many of these natural treasures are merely exported as raw materials. Although the countries including Ghana have an ancient tradition of jewellery production and a large handicraft capacity for manufacturing, jewellery is only exported in very modest quantities, if any at all. This potential can be exploited if the problems in the industry are identified and solved. Ghanaian goldsmiths and other jewellers are all known for their important jewellery manufacturing and have raised their work to the Master craft level, taking on apprentices who help them to produce their works including jewellery. Jewellery is widespread in all cultures in Ghana. The gems and jewellery often say something about general identity, ethnic identity or the wearer’s status. It also reveals the culture in which they originate. Every imaginable resource and item can be used in jewellery production. Be it artificial or synthetic material like plastic, broken bottle etc, or natural materials like leather, animal bone, seeds, coconut shells egg shells, metals like gold, silver, brass, iron, and even clay and tree backs, and also bamboo. In the course of carrying out this work, surveys were carried out on both producers and consumers of jewellery products. The researcher at the end of the work, has unearthed as many problems and solutions as possible. The following methods of research were used to come out with this thesis: Questionnaires to producers and consumers, personal interviews, documents including books, journals, magazines, newspapers, and periodicals were also be used as regards to the review of related literature and Internet. This research project covered Accra, Ho, Kumasi, Koforidua and Cape Coast, and it is hoped that with the recommendations implemented, and the government playing its role, the jewellery industry in Ghana would live up to its desired expectation. Jewellers must also know that they have a role to play in the success of the industry.
Assessing employees’ training needs as an important prerequisite for training programmes: a case study of Internal Revenue Service in Accra- Kinbu District
(2008-08-11) Acheampong, Ernest Yeboah
This research was undertaken as assessing employees training needs as an important prerequisite for training programmes at IRS in Accra, Kinbu district. The intent of the work was to find out whether IRS embarks on training needs analysis before designing training programmes to suit it. Training in IRS-Kinbu district appears to be routine and lacks any thorough pre-training investigations to determine who needs training or what training will be of maximum benefit to the general service goals. The research methodology involved informal interviews and questionnaires were administered to trainers/facilitators, heads of department, human resource manager and district director to assess the organisation training programmes. The analysis of the results of fieldwork clearly showed that there are loopholes in the organisation training programmes. For instance headquarters sole responsibility for initiating training programmes made it difficult for trainers to identify particular skills gap for the individuals since IRS does not employ training needs analysis to select the right and qualified people due for training. It came to light that most of the staff could not transfer whatever they have learnt to the job after training. The fieldwork showed that there is no post training evaluation system in place. It was found out that the organisation training programmes have got a very weak relationship with its performance. Finally the headquarters should provide the trainers with sufficient logistics and materials and carry out training needs analysis before embarking on productive and effective training. Effective evaluation system is highly recommended.
Malaria Transmission Dynamics and Pyrethroid Insecticide Resistance Status of Anopheles Gambiae Sensu Lato Gilles (Diptera: Culicidae) in two Districts of the Brong Ahafo Region, Ghana
(2009) Hayford, Daniel
Malaria results from infection with Plasmodium species transmitted mostly through the bite of female Anopheles species. The Brong Ahafo Region (BAR) of Ghana is endemic for malaria with endemicity greater than 75%. The Ghana National Malaria Control Programme (NMCP) has prioritised the use of pyrethroid-treated bednet and/or indoor residual spraying as a key strategy for combating malaria transmission. Control of malaria transmission using insecticide treated bed-nets and/or IRS impacts on both morbidity and mortality due to malaria. Evidence of insecticide resistance in malaria vectors in different areas necessitates surveillance studies to allow prompt detection of resistance should it arise and thus enable its management. Also, in preparation for the future IRS expansion programme planned by the NMCP, data on indices of malaria transmission would be required from several parts of Ghana, including the BAR. Hence, density, diversity, biting habits, feeding behaviour, parity rates, survival rates, sporozoite rates and entomological inoculation rates (EIRs) as well as pyrethroid insecticide resistance in the main malaria vector were investigated in some communities in two districts of the BAR. Mosquito larvae were collected using the dipping technique and reared to the adult stage and used for the insecticide susceptibility bioassays. Adult mosquitoes were also collected using human landing catches. The susceptibility bioassays were carried out using the standard WHO diagnostic bioassay kits. Bioassays were performed on non-blood fed female mosquitoes 2- to 4-day old. Knockdown rates were recorded after 5, 10, 15, 20, 30, 40, 50, 60, and 80 minutes. Mortality rates 24 hours post-exposure were also noted. Anopheles gambiae complex mosquitoes were analysed using the An. gambiae species specific PCR protocol. DNA from specimens identified as An. gambiae s.s. were subjected to PCR assays for the identification of the M and S molecular forms, and the detection of the leucine to phenylalanine knockdown resistance (kdr) gene mutation. Ovaries of wild-captured adult mosquito samples were dissected to examine the ovarian tracheations in order to determine parity, survival rates and life expectancy. The heads and thoraces of the parous mosquito samples were tested for the presence of circumsporozoite antigens of P. falciparum using enzyme-linked immunosorbent assay. A total of 15,384 Anopheles was collected, 13,088 in the rainy season and 2,296 in the dry season. Three Anopheles species were identified in both seasons: An. gambiae s.l. Gilles (98.80%), An. hancocki Edwards (1.20%) and An. coustani Laveran (0.03%). Anopheles gambiae s.s. was the only member of the An. gambiae s.l. found, consisting of both the M and S molecular forms but the S form was predominant (72.30%). No M/S hybrids were found. The susceptibility tests showed resistance to deltamethrin and permethrin. That is, mortality rates below 80% were observed ranging from 45% to 59% for the 0.05% deltamethrin bioassays conducted at Ahafo Kenyasi and Sunyani respectively. Mortality rates for the 0.75% permethrin bioassays ranged from 27% to 35% for the Ahafo Kenyasi and Sunyani samples respectively. Lastly, 46% mortality was observed for the Ahafo Kenyasi samples tested with 1.5% permethrin. The leucine to phenylalanine kdr gene mutation was detected in the two molecular forms but it was more frequent in the S form. That is, approximately 80.1% and 31.0% of the S and M molecular forms of the An. gambiae s.s. respectively, had the mutation. Anopheles gambiae s.s had its peak biting activity in the third and fourth quarters of the night in the rainy season but activity in the dry season peaked in the third quarter. In the rainy season, human-biting rates did not differ significantly between Sunyani, Ahafo Kenyasi and Hwidiem but the rates in these communities were significantly higher than in Chiraa (p = 0.034). In the dry season, however, there were no significant differences in HBR between the study sites (p = 0.898). Overall biting rates were higher in the rainy season (p < 0.001). Parity and survival rate did not differ significantly between sites but they were higher in the dry season. The sporozoite rate of both the An. hancocki and An. coustani was zero. There were no significant differences in P. falciparum sporozoite rates of An. gambiae between sites and seasons, however, EIRs were higher in the rainy season. The average inoculation rate was 2.864 infective bites per man per night (ib/m/n) in the rainy season, which gives an estimated 85.92 infective bites per man per month (ib/m/m). Comparative figures for the dry season were 0.468 ib/m/n and 14.07 ib/m/m. An overall average inoculation rate was 1.649 ib/m/n, which gives an estimated 49.48 ib/m/m. The results of this study suggest that the An. gambiae s.s. populations are resistant to the pyrethroid (deltamethrin and permethrin) insecticides tested. The implication of this is that malaria vector control measures in these communities using pyrethroid insecticides may be compromised due to the existence of insecticide resistance in the main malaria vector, An. gambiae s.s. The results of this study also suggest that the present study communities are areas of high malaria transmission intensity with transmission occurring all year round even though it is significantly higher in the rainy season.
The anti-termite properties and basic phytochemicals of eight local plants and the chemical characterisation of thevetia peruviana (pers) k. schum in Ghana
(2009) Tagbor, Trinity Ama
There is an increasing interest in the use natural products for termite control because of their environmental safety. Some local plant materials have been mentioned as potential alternatives to synthetic termiticides. The objective of this work was to determine the antitermitic efficacy of locally available plants such as; Thevetia peruviana (pers) K Shum Carapa procera DC, Jatropha curcus L ,Cassia nigricans Vahl, Cymbopogon ginganteus (Hachst) Chiov), Hyptis spicigera Lam., Vetiver zizaniodes Nash (vetiver grass) and Chromolaena odorata (L). Following the identification and collection of the experimental plants and termite samples, a series of field and laboratory experiments were conducted using parts of the plants to determine their antitermite efficacy. Antitermite efficacy was measured as their tolerance to termite damage, repellency and toxicity to termites. This was followed by extraction into petroleum ether, ethanol and water and the analysis of the most efficacious extract by chromatography (thin layer, column and high pressure) and spectrometry (mass spectrometry, nuclear magnetic resonance and infra red) methods to identify the active ingredients in the extract of the most efficacious plant. Resistance to termite destruction was measured by the loss in weight of stakes buried in treated and untreated soil and by visual assessment of extent of destruction. Repellency or attrantancy was determined by counting the number of termites that moved towards or away from filter paper pads treated with extracts of the test material. The results showed that soil treated with pulverised materials from T. peruviana offered the best protection to buried stakes against damage by subterranean termites. Field tests conducted with petroleum ether, ethanol and water extracts of T. peruviana suggested that the ethanol extract of T. peruviana resisted the destructive effects of termites most. In the repellency/attrantancy test, the ethanol extract was found to be an attractant. When the fractionated components of the ethanol extract were tested on brine shrimps, fraction 1 was found to be highly toxic suggesting obvious cytotoxicity. Analysis of fraction 1 by chromatography and spectrometry methods indicated the presence of two components digitoxin and digitoxigenin which were found to be toxic to brine shrimp. Sucrose was also isolated from the crude ethanolic extract of T. peruviana. Thus this work has shown that the potential for the use of anti-termite agents from T. peruviana is promising.
Conversion of Natural Forest to Cocoa Agroforest in Lowland Humid Ghana: Impact on Plant Biomass Production, Organic Carbon and Nutrient Dynamics
(2009) Dawoe, Evans
This study was conducted to assess the effects of forest conversion to shaded-cocoa system on plant biomass, nutrient fluxes and soil physico-chemical properties along a chronosequence (forest, 3, 15 and 30-year-old cocoa farms) in the Moist Semi-deciduous Forest Zone of the Ashanti Region, Ghana. It also explored farmer indigenous knowledge and perceptions of soils and soil fertility dynamic processes. Plant biomass and above-ground organic carbon and nutrient pools significantly declined following changes in land-use compared to soil pools. Tree biomass constituted the largest pool ranging from 12.7 ±1.6 Mg ha-1 for the 3-year-old cocoa system to 209.3±33.3 Mg ha-1 in the forest. Soil Organic Carbon (SOC) in 0-60 cm soil depth did not change significantly over a 30-year period and ranged from 49.0±2.3 to 67.4±1.1 Mg C ha-1 in 3 year-old shaded cocoa system and forest respectively. SOC significantly declined only in the top (0-10 cm) soil at 3 years after conversion but recovered at 15 years. Thirty-year-old shaded-cocoa systems yielded up to 151 Mg C ha-1 primarily stored in established trees (both cocoa and shade trees) and soil pools. Total N declined only in the 10-20 cm soil depth in 3 and 15 year-old treatments but remained stable in all other soil depths across the chronosequence while available P stocks declined significantly. Soil exchangeable Ca, K and Mg stocks remained relatively stable with a tendency to improve, and cation exchange capacity (CEC) and base saturation increased more or less along the chronosequence. Soil bulk density (gm cm-3) increased significantly with increasing age of plantation only for the top 0-10 cm soil layer but did not differ among sites for similar depths. Despite the apparent stability of soil C stocks and nutrients (0-60 cm) along the chronosequence, soil quality declined under cocoa land-use at 3 years. Microbial biomass demonstrated a strong seasonal variation. However, conversion of forest did not result in a significant decline in microbial biomass. Mean annual litterfall and stand litterstocks differed significantly among land-uses. Litterfall ranged from 5.0 Mg ha-1 in 3-year-old cocoa to 10.4 Mg ha-1 forest systems while stand litterstocks were from 3.6 to 5.9 Mg ha-1 in 3 and 15-year-old farms respectively. Annual decomposition coefficients (kL) were similar in cocoa systems (0.221-0.227) but greater under forests (0.354). Estimated nutrient inputs from litterfall was 4 to 165 kg ha-1yr-1 of P and Ca respectively in 15-year-old and forest plots respectively. Turnover of fine roots was 3,591, 1,427, 2,466 and 4,066 kg ha-1yr-1 for forest, 3, 15 and 30-year-old plots respectively. Nutrient inputs through turnover of fine roots were estimated to be 16-31 kg N ha–1year–1, 2 -5 kg P ha–1year–1, 9-36 kg K ha–1 year–1, 18-47 kg Ca ha–1year–1 and 3-25 kg Mg ha–1year–1 across the chronosequence. There were significant differences in incident rainfall, throughfall and stemflow chemistry. Mean annual inputs of nutrients fluxes in incident rainfall were 5.7 kg N, 0.14 kg P, 13.6 kg K, 9.43 kg Ca and 5.6 kg Mg ha-1 yr-1. Rainfall loading or net canopy exchange was negative for total N at all sites while concentrations of P and the basic cations increased in throughfall relative to incident rainfall. Throughfall on average constituted about 95% of the total solute inputs of rainfall origin to forest floor. The mean N and P input-output balances were negative showing the system’s ‘no external input’ character. Farmers in the study had a well-developed knowledge system of their soils and related fertility processes. They derived their knowledge from observable plant and soil characteristics namely; soil color, crop yield, water retention capacity, difficulty to work soil, type and abundance of indicator weeds, leaf color or deficiency symptoms observed on crops and presence and abundance of soil macro-fauna. The qualitative perceptions of farmers matched scientific assessment of fertile or infertile soils. The results suggest the integration of local and scientific knowledge to facilitate the processes for formulating policies and development plans for agriculture truly participatory, gender sensitive and collaborative approaches. Enhancement farmers’ capability to adopt improved farm management and land preparation methods is required to conserve the soil and sustain long-term productivity.
Relationships between Some Anatomical, Physical and Durability Properties of the Wood of Some Lesser Utilised Ghanaian Hardwoods
(2009) Quartey, Gladys Ama
This thesis is the result of a comprehensive study of some anatomical structures as well as some of the properties of wood utilization of selected species and the interrelationship amongst them. The natural durability of ten lesser-known West African Species, namely Albizia ferruginea (Guill. & Perr.) Benth. (Awiemfosamina), Amphimas pterocarpoides Harms (Yaya), Antiaris toxicaria Lesch. (Kyenkyen), Blighia sapida Koenig (Akye), Canarium schweinfurthii Engl. (Bediwonua), Celtis zenkeri Engl. (Esa), Cola gigantea A. Chew. (Watapuo), Petersianthus macrocarpus (P. Beauv.) Liben (Esia), Sterculia oblonga Mast. (Ohaa), Sterculia rhinopetala K. Schum. (Wawabima), and as reference Teak (Tectona grandis), were evaluated by the field test according to EN 252 (1989) for a period of 6 months. Structural size samples were tested for their mechanical properties according to EN 408 (2003). Their water sorption properties were determined at relative humidity conditions of 30, 45, 60, 75, and 90 % at a temperature of 25oC and compared with Albies alba, Picea albies, Fagus sylvatica (European species). Three of the ten species, Albizia ferruginea, Blighia sapida, and Sterculia rhinopetala were selected for anatomical investigations based on their performance in the durability and mechanical strength tests. Microscopic sections of the transverse and tangential planes were made on a Leica sliding microtome, stained and permanently mounted in Canada Balsam. The micrographs were analysed using the stereological technique described by Ifju (1983) and Steele et al. (1976). Maceration was also done. The results from the field test indicate that some of these less utilized species could be used as substitutes for the more standard commercial species in their end use applications. It was found that Albizia ferruginea was very durable, Sterculia rhinopetala was durable and Blighia sapida was moderately durable. A general trend found in the ten species was that, the denser the species the less water/moisture it takes up and the more durable it is, combined probably with specific polyphenolic substances. An exception to this trend was Albizia ferruginea, having the highest sorption of the three mentioned species but at the same time the highest durability and Sterculia rhinopetala the least. The best correlations found between the mentioned properties/features are between density and bending strength, followed by density and sorption, sorption and durability and to a lesser extent density and durability. As could be expected, durability (as a result of natural impregnation with protective substances) was in fact not completely correlated with density: Albizia ferruginea although the lightest of the three specially tested species, had the relatively highest durability according to the graveyard test. Blighia sapida was found to have crystals which could be harmful for working tools. This could explain its brittle behaviour under stress. It had a bending strength of 61.4 N/mm2 at a moisture content of 29 % with an average density of 0.899 g/cm3. A peculiar form of cell wall thickenings has been found in the vessels of this species with the help of scanning electron microscopy. In a third position, Albizia ferruginea had lowest bending strength of 50 N/mm2 at a lower average density of 0.740 g/cm3. In conclusion, Sterculia rhinopetala was used for a pedestrian bridge constructed at the KNUST campus in Kumasi due to its performance in most of the tests carried out and even though most of the tested lesser utilized species were not durable; their durability could be enhanced by impregnation with protective substances in order to be used for external applications.
Asante Folklore and Kumasi Kiosk Architecture:a Visual Exploration of Hybridity and Mythography
(KNUST, 2009-02) OPPONG, E. T.
This studio-based research improvises on the architectonics of Kumasi kiosks. I present the ensuing body of artefacts as a working prototype which joins on-going cultural conversations on hybridity in contemporary art. The typical Kumasi kiosk is referenced as a site for negotiation of boundaries in its design, setting and function, but I have also made allusions to suggestions of hybridity and boundary negotiation in the polyvalent structure of Asante myth and folklore. I made a close study of three hundred kiosks located in the urban quarters of Kumasi. I also engaged such thinkers on hybrid spaces as Homi Bhabha , Jacques Derrida, Michael Foucault, Stuart Hall, Paul Gilroy, etc, to discourse on Asante mythology. I laid emphasis on the myth of ɔhyeεni (ɔhene-king), a patriarchal figure who negotiates boundaries, Asante and Akan filial kinship narrative from Asante history. I employed a personal technique of painting, -Aberphoh, which is a reconfiguration of abstract expressionist and surrealist genres. Asante art forms laden with their myths, some of which visually portrayed mythology, especially the totems, were also studied as the basis upon which art works were recreated in the form of paintings on sculptural structures created with plywood. I used the Asante myth of Abubu-mmabaa to explore the structural dialogue of inside and outside in my hybridized artefact. I have also presented an iconographic catalogue of totems and symbols which appear on the inner and outer surfaces of my structures. I present my project as an artefact to be contained in a gallery space as well as a structure or site which contains other artefacts. Like the Kumasi kiosk, these structures are not intended to be permanently site-specific. Each is collapsible and foldable and thus portable to any possible location for re-erection and exhibition. It is a cross genre installation interfacing painting, sculpture, architecture, poetry and performance.
Soil fertility and microbial biomass carbon, nitrogen and phosphorus dynamics under different amendments and cropping systems In Ghana
(2009-02-05) Logah, Vincent
Biochemical Markers of Oxidative Stress as Indices of HIV/AIDS Progression
(2009-07-12) Obirikorang, Christian
Reactive Oxygen Species (ROS) has been implicated in the pathogenesis and the progression of HIV infection. This study was aimed at investigating the levels of oxidative stress and their probable relationship as markers of HIV disease progression in HIV positive patients in two established HIV/ART centres in Ghana. In all two hundred and twenty eight (228) confirmed People Living with HIV/AIDS (PLWHAs) were included in the study. The subjects were recruited from the Central Regional Hospital (CRH) and Bolgatanga Regional Hospital (BRH). One hundred and forty-three (143; 62.72%) PLWHAs were recruited from CRH and they comprised of eighty one (81; 56.64%) males and sixty two (62; 43.36%) females whilst eighty five (85; 37.28%) PLWHAs were recruited from BRH comprising of forty three (43; 50.59%) males and forty two (42; 49.41%) females. These two hospitals were chosen to give a fair representation of PLWHAs in Ghana. Another 100 sex- and age-matched healthy, HIV-seronegative individuals were studied in parallel as controls. Ethical clearance was obtained from Committee on Human Research, Publications and Ethics (CHRPE), School of Medical Sciences, Kwame Nkrumah University of Science & Technology (KNUST), Kumasi. All subjects gave informed consent to take part in the study after verbal and written explanation of the methods and risks involved had been given. Venous blood samples were taken and assayed for the haematological parameters (haemoglobin (Hb), haematocrit (HCT) and total white blood cell count (WBC), biochemical assays (total Serum Protein, Serum Albumin, Triglycerides, Total Cholesterol, HDL-cholesterol and LDL-cholesterol and markers of oxidative stress (Serum Malondialdehyde (MDA), Ferric Reducing Ability of Plasma (FRAP) and serum Vitamin C and E, Superoxide Dismutase (SOD) Glutathione Peroxidase (GPx). The subjects with the mean age of 36.9±10.9 years which was not significantly different from that of the control group of 39.4+13.4 years. The PLWHAs subjects were grouped per the criteria of the Center for Disease Control (CDC) as: CD4 count (1) ≥ 500 mm-3; (2) 200 – 499 mm-3; and (3) < 200 mm-3. Forty three (43; 18.86%) patients (38.7+10.94 years) had a CD4+ count ≥ 500 mm-3, sixty three (63; 27.63%) patients (37.4+9.54 years) had a CD4+ count between 200 – 499 mm-3 and one hundred and twenty two (122; 53.51%) patients (36.7+10.93 years) had a CD4+ count < 200 mm-3. Markers of oxidative stress revealed significant differences between the patients and control subjects. Malondialdehyde (p<0.001) in the patients was markedly increased as compared to the control group. This suggests increased lipid peroxidation in HIV infected individuals and this increased with the progression of the infection. Ferric reducing ability of Plasma (p<0.0001), Glutathione peroxidase (p<0.0001), Superoxide Dismutase (p<0.0001) were decreased in the patients compared to the control group indicating an increase in free radicals product. Vitamin C (p<0.0001) and E (p<0.0001) were reduced in the patients compared to the control group suggesting a decrease in the antioxidant level as the HIV infection progressed in the patients. Results from the haematological assay revealed a significant decrease in the mean blood haemoglobin levels of the HIV positive patients compared to the control subjects. The significant positive correlation (p<0.0001) between Hb and CD4 count highlights its usefulness in the progression of HIV infection. The haematocrit result pattern showed a consistency with the Hb. There was a significant positive correlation between HCT and CD4 counts (p<0.0001). No significant difference was observed in the total white blood cell count (WBC) of HIV positive patients and the control group (p=0.1830). Apart from serum total Protein (p<0.0001) and Triglycerides (p<0.001), which showed significant increase as compared to the control group, serum albumin (p=0.0106), Total cholesterol (p<0.0001), HDL-cholesterol (p<0.0001) and LDL cholesterol (p<0.0001) showed a significant decrease as compared to the control group. From the correlation analysis, serum Albumin(R=0.41), Total cholesterol (R=0.67), HDL-cholesterol (R=0.27) and LDL cholesterol (R=0.27) showed a positive significant correlation in relation to the CD4 count. However serum total Protein (R=-0.36), Potassium (R=-0.67) and Triglycerides (R=-0.27) did show a negative correlation in relation to the CD4 count. Altogether the findings of this study have revealed that oxidative stress increases as HIV infection progressed. We propose from the study that the interaction of the mechanism underlying oxidative stress and HIV progression and subsequent apoptosis is a receptor-mediated process. During the early phase of HIV infection, generation of ROS has been known to activate HIV replication in vivo through the activation of a factor that binds to a DNA-binding protein, NF-kappa B which is a known activator of HIV replication. This leads to increase in the disturbance in the antioxidant system leading to an increase in ROS production with concomitant biochemical and haematological derangement as observed in the study. Therefore an early intervention with antioxidant supplements in the early phase of HIV infection is likely to reduce HIV progression and improve the immune function.
A user‐friendly colour matching system for tie‐dye/batik producers
(2009-07-13) Frimpong, Charles
The tie-dye/batik industry in Ghana has not lived to its full potential due to shortcomings that include the narrow range of colours available on the market, which in turn, have resulted in products having similar colour schemes. The methods employed in this project are a result of inspiration drawn from colour matching systems used in various industries. Test dyeing experiments were conducted to generate a scheme for generating different shades out of two colours. This scheme was used to generate 130 different shades out of an initial 9 colours. Spectrophotometer tests that serve to determine the unique characteristics of each colour were conducted and spectral curves generated for each mixture. Additionally, tests of reproducibility were conducted on selected mixtures to determine the extent of success of the scheme adopted for mixing. The colours generated, together with some vital information about the mixture have been documented in a catalogue that every tie-dye/batik producer can use and achieve same results. As the first step in changing the status quo, it has been recommended that this solution be brought to the knowledge of producers of tie-dye/batik through the organization of workshops and re-training programmes by interested governmental and private agencies. This coupled with the availability of the basic elements of the system will surely make this solution effective.
Optimizing manure quality for increased food production on small holder farms in the upper east region of Ghana.
(2009-07-13) Ewusi – Mensah, Nana
The beneficial role of cattle manure to improving soil fertility has long been recognized. Its uses however have several drawbacks. One of such drawbacks is the nutrient content which is generally low and variable depending on the feed of the animal and manure management. This study focused on improving the quality of cattle manure for increased maize yields and consisted of five parts: 1. Assessment of the resource quality of cattle manure in seven districts of the Upper East region. 2. Composting of cattle manure. 3. Laboratory - incubation studies to determine nutrient release patterns of compost. 4. Field decomposition studies of buried compost in litter bags. 5. Assessment of the effects of compost, cowdung and NPK fertilizer on crop growth and yield. A survey was conducted in seven districts of the Upper East region using structured questionnaires to seek information on management practices likely to influence manure quality such as storage and handling. The survey revealed that nitrogen losses up to 100% were sometimes obtained by the time the manure was incorporated into the soil. An initial resource quality analysis of the manure sampled from the seven districts was conducted in the laboratory using standard protocols. The results indicated that N and P contents of the manure ranged from 0.27 to 1.14% and 0.28 to 0.76% respectively, which were all below the critical levels for net mineralization. Polyphenol levels on the other hand were lower than the critical value of 4%. Decomposition and nutrient release from the manure showed immobilization of total N during the first four weeks, suggesting the need to improve the quality by composting or by applying it in combination with mineral fertilizers. In an attempt to improve the quality of the manure, composting with Stylosanthes guinensis using the aerated pile method was carried out. Two main compost types (1:1 and 2:1 ratios of cowdung to plant material) were prepared. Total N and P contents of the composts at the end of study period ranged from 1.10 to 1.46% and 0.28 to 0.31% respectively. Mineralization studies on the resultant composts were conducted under laboratory (leaching tube method) and field (litter bag technique) conditions. Under laboratory conditions, both compost types showed net N and P immobilizations during the first two weeks of incubation. However, under field conditions, net N and P mineralization rates were observed throughout the study period for both compost types. Half life values (time required for 50% of the initial mass to decompose) of 8 and 10 days respectively were recorded for the 1:1 and 2:1 compost types. Furthermore, the 1:1 compost had a higher decomposition rate constant (k = 0.085) than the 2:1 compost (k = 0.056). In all cases, negative correlations were observed between the mass of composts remaining and nutrient released. The contribution of the composts to improving the fertility of the soil and hence crop growth was evaluated by comparing maize response to various rates of the composts with optimum mineral fertilizer combinations. The results showed that the 1:1 compost treatment at 3 t/ha, produced the highest maize grain yield (4.99 t/ha). Maize grain yields obtained from both compost types compared very well with NPK fertilizer suggesting that composting of cattle manure with Stylosanthes guinensis enhanced its quality and nutrient release potential for increased crop yield.

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