Doctoral

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A Modal Approach To Price An Option In Continuous Time
(KNUST, 2018) Osei Antwi
Average value options or Asian options have been priced using geometric and arithmetic averages of the underlying asset. However, these methods do not give accurate results especially in very low volatility regimes. In this study, we develop a new option pricing model based on the modal average of the underlying asset to price options. Using data from the NASDAQ in the United States of America we use the proposed model to price options sold on some stocks listed on the exchanges using software. The results consistently showed that for volatilities less than 3% of the underlying asset, the modal average option pricing model gives a better option price when compared to existing average option pricing models. Moreover, the modal average consistently does better at all levels of volatility when compared to the Black-Scholes model. We further proved analytically that the modal average model indeed does better than the geometric or arithmetic average models especially for low volatility stocks.
Addressing HIV/AIDS pandemic in the Ejura-Sekyedumase District: a study of knowledge, attitudes and sexual behaviour among unmarried 15-24 year-olds
(2009-08-05) Agyemang, Seth
Statistics show a rising incidence of HIV/AIDS infection in the Ejura-Sekyedumase District of the Ashanti Region in Ghana. In spite of this development, many people in the district have limited knowledge and serious misconceptions about the disease. Some deny its existence, while others attribute it to factors such as curses, witchcraft and mosquitoes. Discussions with parents, opinion leaders and young people also confirmed that premarital sex is on the ascendancy in the area, contributing to the increase in the pandemic. The research therefore sought to examine the effects of knowledge of HIV/AIDS and attitudes on the sexual behaviour of unmarried people aged 15-24 years in the study area. Both quantitative and qualitative data were employed. The quantitative data was obtained through questionnaire administered on a random sample of 450 unmarried people aged 15-24 years. The qualitative data was obtained through in-depth interviews and focus group discussions. The effects of knowledge and attitudes on sexual behaviour were and the testing of the hypotheses were done using the chi square tests, with p≤0.05 as the level of significance. Other modes of analysis were frequency tables and bar graphs. There were four hypotheses for the study: (1) Knowledge of HIV/AIDS is significantly higher among people living in urban areas compared to those living in the rural areas. (2) Higher knowledge of HIV/AIDS results in less sexual activity. (3) Positive attitudes towards premarital sex results in less sexual activity, and (4) The higher the level of self-perceived risk of acquiring HIV/AIDS, the lower the level of sexual activity. The study used a modified form of the Health Belief Model as its conceptual framework. The results showed that 47.3% of the respondents had had sex. The mean and the median ages at first sexual intercourse were 17.5 years and 18 years respectively. The most important sources of information on HIV/AIDS were radio and television. Three of the four hypotheses were justified. Knowledge of HIV/AIDS was significantly higher in the urban area compared to the rural areas (p=.000). Secondly, high self-perceived risk of getting HIV/AIDS was associated with less premarital sex (p=.000). Thirdly, positive attitudes towards premarital sex resulted in less sexual activity (p=.007). However, the hypothesis on the relationship between knowledge of HV/AIDS and sexual behaviour could not be justified as the result was not significant (p=.058). Other results were that education had a positive effect on knowledge and several attitude variables. Sexual activity was lower among respondents who perceived a higher self-efficacy to abstain from premarital sex (p=.000), and among those who believed they could refuse sex for money (p=.007). Condom use at last sexual intercourse was also higher among respondents who perceived a higher self-efficacy to insist on condom use (p=.012) and among those who believed that condoms are effective in preventing HIV/AIDS (p=.009). Contributions to knowledge by the research include the provision of a comprehensive conceptual framework and justification for a combination of qualitative and quantitative methods in studying knowledge, attitudes and sexual behaviour. The findings call for increased access to formal education to defuse false perceptions and beliefs about HIV/AIDS, sustained education and communication on HIV/AIDS, HIV/AIDS education in health settings, accessibility to condoms, and financial/economic empowerment. Unmarried people also need practical skills to be able to translate knowledge on HIV/AIDS into behavioural change. Some areas for further studies have also been suggested.
Adoption and Effects of Climate Change Adaptation, and Land Use Decision of Smallholders Farmers in the Saline Area of Sine-Saloum, Fimela Senegal
(2023-07) Thiam, Habibatou Ibrahima
Soil salinity expansion is one of the most severe land degradation issues confronting farmers in Senegal, particularly in coastal areas such as Fimela. With sea level rise, temperature rise, and rainfall decrease, soil salinity is increasing significantly. It has a negative impact on crop yields and farmers' livelihoods. Farmers developed land use adaptation strategies to deal with soil salinity. Nonetheless, despite adaptations, some farmers continue to complain about the negative impact of soil salinity on their outcomes. Then, this study investigates farmers' adaptation, the different factors that influence it, its implications for smallholder farmers' livelihoods, and farmers' perception of soil salinity and its impact. Data from face-to-face interviews of 288 households using the Krejci and Morgan’s formula and GPS coordinates of households and each of their farms was collected. An agent-based model was used to understand land use adaptation to soil salinity expansion by considering farmers' perceptions of soil salinity expansion under climate change for simulation. A sub-model of household decisions, crop yield, and perception of soil salinity was developed and incorporated into the model. Three scenarios were considered to simulate the interaction between household agents and landscape agents over 25 years. Farmers' adoption is influenced by their assets and sociopsychological factors like threat assessment, coping assessment, and subjective norms. Farmers in Fimela do not have maladaptation thinking that may break their willingness to adopt strategies to cope with soil salinity. The ESR model shows that farmers' adoption of strategies to cope with soil salinity has a positive impact on groundnut yields and a negative influence on food security but has no significant effect on their millet yields. These findings have been validated by the simulation results, which show that the yield difference between farmers who perceive soil salinity expansion and those who do not is significant for groundnut but not millet over 25 years. As a result, it is critical to base policies in combating soil salinity effects on providing better methods of soil salinity adaptation strategies through scientific research. Policies should support a few pilot farmers in these precise and effective strategies to trigger other farmers to follow through the village and social influence by the farmer-to-farmer approach to enable farmers access and appropriation of these new methods.
Adversarial Relationships in Design Service Delivery in Ghana: Effects on Supply Chains Information Flow and a Business Relationship Management Proposals for Improvement
(NOVEMBER, 2015) Orgen, Nanyi Kobina
The construction industry in developing countries like Ghana faces a number of Design Service Delivery (DSD) challenges. These challenges include non-collaborative activities and adversarial business relationships among various construction actor groups and clients. Such challenges mostly end in discords, disputes and conflicts (DDC). Subsequently, while the discords, disputes and conflicts are pervasive and not in doubt, the impact is not known, making it difficult to appreciate the severity of the problem and also to propose appropriate measures for addressing the problem. In view of these challenges this study aims at developing a framework for the empirical understanding of the nature of adversarial business relationships and how they impact on the supply chains of information flow (SCIfs) for DSD activities in Ghana and also to put together the attitudinal behaviours that can be proposed for improvement. An extensive review of relevant literature helped to identify concepts, issues, frameworks and models essential for isolating both collaborative and non-collaborative activities in business relationships. Using relevant theories such as the action oriented system theory, thinking and rethinking, and the inclusion of pertinent cultural issues like individualism and collectivism, a theoretical framework has been developed. Non-probability sampling methods such as purposive, non-proportional quota sampling were used to select samples. Further, the samples have been drawn through eligibility selection criteria. The criteria enabled the selection of forty-five DSD participants (interviewees) suitable for interview. The interviewees included Chief Executives and Senior DSD actors of both public and private companies with over 10 years experiences in DSD activities in Ghana and the West African sub-region. Qualitative data were collected electronically with automatic voice recording, written summaries from the participants and recorded observations were carefully analysed using conventional, directed and summative content analyses techniques, supported by Pareto analysis. The research contributes to knowledge by revealing the nature of the adversarial business relationships in three broad categories: no collaboration, less collaboration and close-to-average collaboration relationships among the DSD actor groups. Again, the study shows that the nature of SCIfs is as disjointed (36% frequency); fragmented and uncoordinated (16% each). These three attributes account for a total of 68% frequency. This describes the serious challenges that the nature of adversarial relationships impose on the current SCIfs developed and constituted especially in Ghana. The attributes used to describe the construction business relationships predominantly confirm the literature claims of non-collaborative business relationships, which cause improper functioning of the processes and procedures used in developing the SCIfs. The malfunctioning processes and procedures reveal 'unsystematic and insufficient details'; 'inconsistent or use of outmoded design, interpretation and transfer methods. Additionally, the processes and procedures show ‘sub-standards with gaps or no standard for supply chains' and ‘the use of weak incomplete supply chain'. The five attributes outlined also account for a total of 68% inefficiencies which cause malfunctioning of the processes and procedures used in developing and constituting SCIfs in Ghana. Based on these identified challenges as pre-conditions, 23 attitudinal behaviourial attributes and 15 technical attributes of knowledge required to transform the situation have been identified from the study. Additionally, assessment and improvement frameworks for quality improvement of the DSD activities based on the pre-conditions and multi-theories among other concepts, attitudinal behaviourial attributes and technical attributes of knowledge have been developed. This could be used for collaborative, harmonious and cordial business relationship in developing and constituting the SCIfs for hygienic, cost and time effectiveness in infrastructural development.
Aesthetic and Educational Underpinnings of signs and symbols among the Central Ewes of Ghana
(2012-07) Atiase, Cleveland Edem Kwesi
The Central Ewes have identifiable signs and symbols that are of significance to them. The youth, especially, do not adequately benefit from them. The older generations are dying with the knowledge, so a gap is created as to how to learn the accumulated knowledge and values from the signs and symbols. Central Ewe signs and symbols are also not generally known and the larger population is generally not familiar with their values. They are ‘coded’ and need to be unravelled for better appreciation. In order to solve the problem, the research sought to identify and discuss the signs and symbols, their aesthetic and educational values. The study sets out objectives, which help develop a structured interview guide to gather information. Geographically, the study is limited to eleven (11) towns in the Central Volta region of Ghana. Twenty-one (21) signs and twenty (20) symbols were identified. The signs and symbols have aesthetic and educational values from which moral lessons are learnt and it is an integral part of their everyday life. Central Ewes also have additional concepts of aesthetics which spell out the theory of excellence. Besides, they equate beauty with function or usefulness. Some of the signs and symbols are similar to that of the Akans. Their use will achieve cultural unity among the Central Ewes and other cultures, especially non-Ewes in the country.
Aesthetic and Educational Underpinnings of Signs and Symbols among the Central Ewes of Ghana
(2015-04-20) Edem Kwesi Atiase, Cleveland
The Central Ewes have identifiable signs and symbols that are of significance to them. The youth, especially, do not adequately benefit from them. The older generations are dying with the knowledge, so a gap is created as to how to learn the accumulated knowledge and values from the signs and symbols. Central Ewe signs and symbols are also not generally known and the larger population is generally not familiar with their values. They are ‘coded’ and need to be unravelled for better appreciation. In order to solve the problem, the research sought to identify and discuss the signs and symbols, their aesthetic and educational values. The study sets out objectives, which help develop a structured interview guide to gather information. Geographically, the study is limited to eleven (11) towns in the Central Volta region of Ghana. Twenty-one (21) signs and twenty (20) symbols were identified. The signs and symbols have aesthetic and educational values from which moral lessons are learnt and it is an integral part of their everyday life. Central Ewes also have additional concepts of aesthetics which spell out the theory of excellence. Besides, they equate beauty with function or usefulness. Some of the signs and symbols are similar to that of the Akans. Their use will achieve cultural unity among the Central Ewes and other cultures, especially non-Ewes in the country
Aesthetic and Educational Underpinnings of Signs and Symbols among the Central Ewes of Ghana
(2015-05-22) Atiase, Cleveland Edem Kwesi
The Central Ewes have identifiable signs and symbols that are of significance to them. The youth, especially, do not adequately benefit from them. The older generations are dying with the knowledge, so a gap is created as to how to learn the accumulated knowledge and values from the signs and symbols. Central Ewe signs and symbols are also not generally known and the larger population is generally not familiar with their values. They are ‘coded’ and need to be unravelled for better appreciation. In order to solve the problem, the research sought to identify and discuss the signs and symbols, their aesthetic and educational values. The study sets out objectives, which help develop a structured interview guide to gather information. Geographically, the study is limited to eleven (11) towns in the Central Volta region of Ghana. Twenty-one (21) signs and twenty (20) symbols were identified. The signs and symbols have aesthetic and educational values from which moral lessons are learnt and it is an integral part of their everyday life. Central Ewes also have additional concepts of aesthetics which spell out the theory of excellence. Besides, they equate beauty with function or usefulness. Some of the signs and symbols are similar to that of the Akans. Their use will achieve cultural unity among the Central Ewes and other cultures, especially non-Ewes in the country. July, 2012
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.
Aesthetics, appreciation and criticism among indigenous Asante kente weavers: implications for art education and national development
(2009-08-11) Sabutey, Gordon Terkpeh
This dissertation unravels the concepts of aesthetics, appreciation and criticism among the indigenous Asante Kente weavers and its implication for Art Education in Ghanaian schools and colleges as well as national development. Research has shown that, any education however “civilized” it might be which is not based on the culture of the people receiving that education is bound to produce societal misfits. The indigenous Asante Kente weavers have for several decades produced rich Kente Cloths. They have exhibited and promoted the rich Ghanaian cultural values that are embedded in their weaves. Thus, these philosophical values in the art works they produce are in the form of events, proverbs, stories, historical records and other aesthetic values projected from the cultural context. However, the researcher believes that knowledge in the concepts of aesthetics, appreciation and criticism acquired from the indigenous Asante Kente weavers is a very good source of aesthetic education in schools and colleges. Concepts of aesthetics, appreciation and criticism are areas of study in art education. Unfortunately, they are mostly neglected or mistreated art programmes. Aesthetics is a form of knowledge involving appreciation and criticism with its importance not only limited in schools but the entire community. Foreign education or Western culture has had tremendous influence on students in Ghana. It is very imperative to introduce students to African philosophy of life, especially, that which deals with the relationship between art and life in general. This research therefore, aims at discussing, analyzing and documenting the concepts of aesthetics, appreciation and criticism among the indigenous Asante Kente weavers, discussing the aesthetic values of some of the woven pieces, the philosophical concepts behind the use of the various cloths, implication for national development such as tourism and employment so as to use these concepts to augment teaching and learning in schools and colleges in Ghana. In order to achieve these objectives, the researcher in his analysis, deployed the use of The Statistical Package for Social Sciences (SPSS) Data Analysis Programme, especially to quantify the data. This programme was considered very helpful especially in analyzing the quantitative data. This brought very accurate information by generating tables, bar charts and percentages of ideas from respondents. A lot of essential data were collected, assessed and analysed and discussed with hypotheses tested. As discussed, qualitative and quantitative analyses were used to extract information from the data collected. The SPSS data analysis was utilized by the researcher because of its accuracy of outputs of results. The researcher also employed tools of research such as questionnaires, interviews and observation. Data were also collected from available relevant or related literature based on the topic, in the form of text books, journals, magazines, news papers, newsletters, the internet and other related sources. The stratified /simple random sampling, focused group discussion and purposive sampling techniques were used to sample master weavers, junior weavers and apprentices. In all, eighty (80) respondents were selected from a population of three hundred (300) weavers, which constitutes more than 30% of the population. These weavers were selected from 4 Kente weaving centres within the Ashanti Region. Moreover, in the case of the customers or users of the Kente cloth, questionnaires were administered to express their views on the aesthetic concepts of the cloth. The researcher also administered questionnaires each to experts of art education (including directors of education, lecturers, etc.) and students for enhancement of this dissertation. The researcher in his efforts therefore, arrived at several findings based on objectives and other vital information, yielding new knowledge for the benefit of art education and national development. These major findings include: The indigenous Asante Kente weavers have their own criteria for assessing the beauty of their Kente Cloths; they have their own terms for beauty and criticisms; have special names and symbols for cloths; for centuries they project cultural and historical values through indigenous arts including Kente cloths in the sense that events, proverbs, beliefs and folktales in the past were recorded in their cloths; that their cloths reflect intrinsic and other extra-aesthetic values - they are seriously integrated with various Ghanaian events and celebrations; they serve as great legacy, national identification and a sign of prestige, cultural preservation. The study of the indigenous Asante Kente cloth will promote and enhance aesthetic education in Ghanaian schools and colleges, national development through employment, exports and tourism; Knowledge about Kente cloth discussed in the thesis is an expansion of knowledge about Kente cloth in general as well as exposure about other cultures. The researcher has therefore, provided useful recommendations in the text. The teaching and learning of aesthetics, appreciation and criticism should be strengthened in schools and colleges bearing in mind the socio-cultural underpinnings of these concepts.
Agricultural Land Use Change in the Lowlands of Southern Mali under Climate Variability
(KNUST, 2023-07) Traore, Alou
This research investigated agricultural land use change in the lowlands of Southern Mali under climate variability. Four supervised classification techniques, Classification and Regression Tree (CART), Support Vector Machine (SVM), Random Forest (RF) and Gradient Tree Boosting (GTB) in Google Earth Engine (GEE), were used for the image classification. An integrated Cellular Automata-Artificial Neural-Network (CA-ANN) within the MOLUSCE plugin of QGIS was used for future Land Use and Land Cover prediction. The Mann-Kendall test, Sen’s slope, Pettit-test and change-point detection analyse were applied for climate variability assessment. Monthly rainfall and mean temperature extending over a period of 61 years (1960–2020) recorded at Sikasso District were analysed. Annual rainfall varied between 800 mm to 1600 mm and annual mean temperature ranged between 25 oC to 28 oC. Seasonal rainfall ranged between 37-387 mm, March-April-May (MAM), 400-1030 mm, June-July-August (JJA), 77-577 mm September-October-November (SON) and 0-45 mm for December-January-February (DJF). Mean seasonal temperature ranged from 29 oC to 32 oC (MAM), 26.5 oC to 28.5 (JJA) oC and 26 oC to 28 oC (SON). Annual and seasonal rainfall trends increased slightly. Temperature showed a significant increase in both annual and seasonal trends. Out of 395 respondents, 79 % were of the view that annual rainfall decreased while 83 % reported mean temperature increased. Again, respondents perceived late onset rainfall (97 %), early cessation of rainfall (96 %), increased in drought (83 %) and flooding (96 %). Also, 43 % of respondents adopted new varieties to cope with climate variability. The findings showed that physical and socioeconomic driving forces had impact on terrain patterns. Over the past three decades, the study revealed that apart from cropland area which increased from 43.81 % to 52.75 %, the size of the other land uses decreased, forest cover (19.93 % - 13.93 %) shrubs (16 % - 14 %), and streams (6 % - 4 %). However, the forecast for the 2020 to 2030 predicted an increasing trend in forest cover and decreasing trend in agricultural land in the study area due to the ongoing afforestation projects. The study demonstrates the need to reinforce regional land management policies and programmes.
The Agronomic qualities of the Mexican Sunflower (Tithonia diversifolia) for soil fertility improvement in Ghana: an exploratory study
(2010) Partey, Samuel Tetteh
Soil fertility depletion remains a major biophysical constraint to increased food production in Ghana even when improved germplasm has been made available. With the growing concern of the potential of low input agriculture in mitigating soil fertility challenges, exploratory researches are imperative in selecting best quality organic materials that meet this expectation. This study was conducted to assess the suitability of Tithonia diversifolia green biomass as a nutrient source for smallholder agriculture in Ghana using both on-station and on-farm trials. The on-station research comprised an evaluation of the decomposition and nutrient release patterns of T. diversifolia in comparison with well-known leguminous species of agroforestry importance: Senna spectabilis, Gliricidia sepium, Leucaena leucocephala and Acacia auriculiformis. Concurrently, field trials were conducted to appraise the quality of T. diversifolia green biomass in relation to its biophysical effects on soil properties and the agronomic characteristics of crops. This was a comparative study with S. spectabilis, G. sepium and mineral fertilizer on a ferric acrisol. Field trials were also conducted to determine best practices for optimum biomass production of T. diversifolia using different pruning regimes and cutting heights as factors. The on-farm research was conducted at Dumasua in the Brong Ahafo Region of Ghana to appraise 200 farmers’ preliminary knowledge of T. diversifolia and evaluate the effect of T. diversifolia green biomass on soil fertility indicators and crop yields. The results of the decomposition study confirmed significantly high N, P, K concentrations in T. diversifolia comparable to levels recorded for the four leguminous species. In addition, T. diversifolia recorded the highest decomposition and nutrient release rates which differed significantly (p < 0.05) vii from rates of the four leguminous species. Although decomposition and nutrient release rates of species were related to quality of leaf material, P and Mg concentrations in particular were most influential in decomposition and nutrient release based on significant results. The on-station trials showed significant effect of the green manures (particularly T. diversifolia) on soil properties and the biomass and fruit yield of okro (Abelmoschus esculentus). These results were comparable and in some cases greater than fertilizer treatments. Total yield response in T. diversifolia treatment was 61% and 20% greater than the control and fertilizer treatments respectively. From the pruning experiment, it was evident that height of cutting, pruning frequency and their interaction significantly affected dry matter production of T. diversifolia. Dry matter production was highest (7.2 t ha-1yr-1) when T. diversifolia was pruned bi-monthly at 50 cm height. Results from the sociological survey confirmed farmers’ general knowledge on T. diversifolia at Dumasua was poor. Although majority of respondents had seen the plant growing, none could give a common name. Only the ornamental importance of T. diversifolia was identified. Meanwhile, the on-farm trials revealed a significant synergistic effect of combining T. diversifolia and fertilizer on soil nutrient availability and harvest index of maize. The results showed that the application of Tithonia either alone or in combination with fertilizer can increase yield by 24% and 54% respectively compared to plots which received no inputs.
An Integrated Approach To Buruli Ulcer Transmission Studies: From Aquatic Environments To Human Infection
(KNUST, 2018-04) Charles Quaye
Buruli ulcer (BU) is a debilitating skin infection usually of impoverished tropical rural populations. BU is caused by Mycobacterium ulcerans (MU), a pathogen described as a non-tuberculous mycobacteria (NTM). The exact mode of transmission of BU is not known and involvement of insect vectors including mosquitoes, animal and small mammal reservoirs and aerosols in transmission and dispersal has been proposed. A holistic approach to studies that involve NTM is proposed especially in transmission and control studies. This study related human MU infections to MU types in identified risk areas and establishing sources of human infections. Water body type preferences of members of the two most implicated insect families in BU transmission, Family Belostomatidae (Hemiptera: Heteroptera) and Family Naucoridae (Hemiptera: Heteroptera) collected from water bodies in Ghana and Cote d’Ivoire were also related to their probability of being involved in transmission of BU. Four BU endemic communities (Bepotenten, Sukuumu, Monia-Gyaman and Wromanso) in the Amansie Central District of the Ashanti Region of Ghana were selected for the study. Two hundred and twenty-four (224) questionnaires administered proportionally to population were used to elicit responses to water use and areas of contact, BU knowledge, animal contact and infection status. Ground truthing of the four communities and the capturing of geographical information allowed the reconciliation of questionnaire water contact points and the subsequent mapping to reveal all surface water contact points. M. ulcerans from environmental sources was detected using 16S rRNA and then IS2404 detections. M. ulcerans genetic material from both human BU cases and identified environmental sources were VNTR (viable number tandem repeats) typed at four loci (VNTR targets: MIRU1, Locus 6, ST1 and Locus 19. Swimming and bathing (p=0.04) in risk environments and the capture of squirrels (p=0.04) were associated with an increased in the risk of acquiring BU in the study communities (OR= 3.28 and OR=5.85 respectively). Rigorous activity in infected water was found to increase the risk of infection laying credence on a direct trauma infection route for M. ulcerans. VNTR typing of MU from human BU disease and environmental samples revealed localized infection with inhabitants mostly being infected from community associated water bodies. Four main VNTR types were detected in human disease MU based on number of copies of four loci: MIRU1, Locus 6, ST1 and Locus 19. These were ‘W’ (1,1,2,1), ‘X’ (1.1.2.2), ‘Y’ (1,2,2,1) and ‘Z’ (1,2,2,2) in the copy number order MIRU1, Locus 6, ST1, Locus 19. The ‘Y’ VNTR type was common to all communities being detected in human as well as environmental samples and is therefore the profile causing the most infections in the study communities. A total of 125 and 321 individual Naucoridae (Hemiptera: Heteroptera) and Belostomatidae (Hemiptera: Heteroptera) respectively were classified to at least genus level. Eight species of the Naucoridae were identified; Ctenopocoris africanus (Leach, 1815), Aneorocoris insolitus (Montandon, 1897), Laccocoris limicola (Stal, 1855), Laccocoris spurcus congoensis (Poisson, 1949), Neomacrocoris bondelaufa (Sites, 2015), Neomacrocoris vuga (Sites, 2015), Naucoris obscuratus (Montandon, 1913) and Neomacrocoris usambaricus (Montandon, 1913). Differences in habitat preference of the Naucoridae were observed. Naucoris spp and Laccocoris spp showed the least preference for lotic water bodies (p<0.05). Four genera of the family Belostomatidae; Abedus, Diplonychus, Lethocerus and Benacus, were identified in collections from 82 water bodies in Ghana and 7 water bodies in Cote d’Ivoire. Abedus spp were the most abundant and most widely distributed. Belostomatidae showed no preference to type of water flow (p=0.2068). The integrated approach of the study offered complementary information, observations and deductions which together enabled verifiable conclusions to be drawn on the transmission of the environmental mycobacterium. The use of few communities facilitated a more concentrated search for risk areas and their link to BU infections in the study communities. A study involving a higher number of communities in a similar geographical range is recommended. In insect transmission studies, individual species competence should be considered and generalizations minimized as species preferences to habitat are important especially in studies involving NTMs.
Analgesic and Anti-Inflammatory constituents of annickia polycarpa stem and root barks and clausena anisata root.
(AUGUST, 2016) Kumatia, Emmanuel Kofi
Clausena anisata and Annickia polycarpa are medicinal plants used to treat various painful and inflammatory disorders among other ailments in traditional medicine. The aim of this study was to investigate the analgesic/antinociceptive and anti-inflammatory activities of the ethanol extracts of C. anisata root (CRE), A. polycarpa stem (ASE) and root barks (AR) in order to provide scientific justification for their use as anti-inflammatory and analgesic agents. Analgesic activity was evaluated using the hot plate and the acetic acid induced writhing assays. The mechanism of antinociception was evaluated by employing pharmacological antagonism assays at the opioid and cholinergic receptors in the hot plate and the writhing assays. Anti-inflammatory activity was also evaluated by carrageenan induced edema in rats’ paw assay. The compounds were isolated using bioassay-guided fractionation and their structures identified by spectroscopic methods. CRE at 1000 mg/kg p.o. produce significant (p < 0.001) analgesic activity of 72.15 and 48.05 % in the hot plate and writhing assays respectively and significant (p < 0.01) anti-inflammatory activity of 27.53 %. ASE also produced significant (p < 0.001) analgesic activity of 82.54 and 44.03 % in the hot plate and writhing assays respectively and significant anti-inflammatory activity of 69.64 %. Furthermore, the results also showed that the petroleum ether (pet ether) fraction (PEF) of C. anisata root extract and the chloroform fraction (AC) of A. polycarpa stem bark extract were the most active fractions among the petroleum ether, chloroform and aqueous fractions of these extracts. A total of seven (7) compounds were isolated. Four (4) coumarins, namely, anisocoumarin B, osthol, imperatorin and xanthotoxol in addition to a carbazole alkaloid, heptaphyline were isolated from PEF. Two (2) protoberberine alkaloids namely jatrorrhizine and palmatine were also isolated from AC. Palmatine was further isolated from the chloroform fraction of A. polycarpa root bark. The seven isolated compounds were tested for analgesic activity in the writhing test. Six of them at 6 mg/kg p.o., produced significant analgesic activity of 38.13 to 47.28 %. One of the isolates (xantothoxol) was inactive. Analgesic activity of diclofenac in the writhing test was 32.92 % at 6 mg/kg p.o. Four of the isolates were also tested for analgesic activity in the hot plate assay. These isolates at 9 mg/kg p.o. produced immence analgesic effect of 30.13 to 93.87 %. The analgesic effect of tramadol 9 mg/kg p.o. was 27.13 % in the hot plate test.
Analysis and modelling of suspended sediment concentration of rivers in catchments experiencing land cover degradation
(October, 2019) Boakye, Ebenezer
Amongst the issues threatening water security and sustainability is the increasing rate of river sedimentation. Variations in catchment sediment yield results from the variations in its controlling factors such as land use/cover characteristics. Thus, it is crucial that this factor is monitored and managed to ensure sustainability of the resource. However, existing models (statistical) have failed to explore the influence of the land use types. Hence, land cover effect and its associated modifications on the variations in suspended sediment concentration have not been empirically quantified, especially for catchment with heterogeneous land cover classes. In view of this, this research answers the question “To what extent does land use/cover characteristics influence the variations in catchment suspended sediment yield?” The following specific objectives were addressed: (1) to assess the trend and extent of land use /cover changes in the Pra River Basin and their driving forces; (2) to assess the variations in suspended sediment yield of the catchment; (3) to determine the sediment generating areas of the catchment and (4) to assess the relative importance of land use types on the variation of suspended sediment yield and to forecast same. Remote sensing and Geographic Information System techniques, field measurement, data collection and laboratory analysis, and statistical techniques such as Analysis of Variance, multiple regression and correlation analysis were employed for the study. Results reveal that between 1986 and 2018, the Pra River basin had suffered severe land cover degradation resulting from anthropogenic influence. Land use conversion occurred generally from closed and open forest to farmlands, settlement and mining. However, the rate, extent and trend of conversions differed significantly across it sub-basins. Sediment yield of the basin is very high ranging between 13.29 and 215.02 tkm-2yr-1, and differs significantly (p < 0.05) with respect to the contributing drainage basins. Erosion map showed that about 21.3% of the basin comes under severe and very severe erosion risk category. Soil erosion rate varied with land use types in a decreasing order from Mining to Settlement, Farmland/grassland, Open forest and Closed forest. Lower Ofin, Anum, Birim, Twifu Praso, Upper Ofin and Oda sub-basins were identified to be susceptible to high erosion. Model accuracy increased from 60.2% to 76.7% when land cover types were included as predictor variable in the suspended sediment concentration model. This indicates that land cover characteristics play a significant role in explaining the variations in catchment suspended sediment yield. The study recommends that immediate conservation measures and policy implementation must be put in place to restore the ecological integrity of the degraded sub-basins. The need to form district ecological or environmental task force involving officials of water, environment and security agents can be useful in handling respective sub-basin’s environmental threats. This will preserve the water resources for sustainable use.
An analysis of a peri-urban sanitation market and farmers’ perception on excreta reuse in agriculture in Dangme West District, Ghana
(MAY 2016) Nimoh, Fred
This study sought to analyse a peri-urban sanitation market and farmers’ perception on excreta reuse for agricultural purpose in Dangme West District of Ghana. Specifically, the study examined the constraints, motivations and strategies to the operation of sanitation business; analysed financing mechanisms and willingness-to-pay (WTP) for improved household latrines; investigated farmers’ perceptions toward excreta reuse for agricultural purpose; and reviewed literature on regulatory policies for sustainable sanitation. Data were collected using observations, interview guide and survey questionnaire. Descriptive and inferential statistics were used for data analysis and reporting. The motivations and constraints to sanitation business were examined using case sanitation service providers (SSPs). Budgetary estimates and the logit/logistic model were employed to analyse households’ latrine financing decisions, and their WTP for improved household latrines, using the contingent valuation method (CVM). Farmers’ perception on excreta reuse as fertilizer was analysed with a Likert-type scale and the ordered probit model. Results of the study showed that there exist various sanitation-related businesses such as latrine builders/masons, hardware suppliers and pit-emptiers, who operate as sole proprietors in a market characterized as monopolistic competition in the study area. Sanitation business in the study area was found to be profitable, despite the financial, institutional and social challenges to the SSPs’ business. The study found that a majority of the households practise open defecation (ODF), though they prefer improved latrines, particularly the flush latrine and ventilated improved pit (VIP) latrine. Lack of space and funds, availability of alternative option (beach) and no economic value for excreta were mentioned by the households as key considerations to owning a household latrine. A comparison of the households’ income and expenditure showed that the households have sufficient income to finance the construction and management of their latrines, contrary to the claim that they do not have funds to build a household latrine. A majority of households were willing to pay for improved latrines via savings rather than the use of credit, although the financial institutions in the study area are interested to offer loans for household latrines. Empirical results from the logistic model showed that there exists some relationship between households’ latrine financing decisions and their socioeconomic and community characteristics such as gender, education, household composition, income, tenancy, defecation practice and location of community. It was also found that a majority of farmers ‘disagree’ that excreta are a waste and they would use excreta as fertilizer if sterilised; as they ‘agree’ that excreta could pose health risks. Empirical results showed that a farmer’s decision to use excreta as fertilizer is more related to the perception on excreta as a resource, experience in community, household size, income, and land tenure system. Regulatory options identified for sustainable sanitation include the use of community-based organizations, the professional and trade associations, and consumers as 'watch groups'. Based on the findings of the study, the following recommendations, among others, have been made to help improve the Ghanaian peri-urban sanitation: there is the need to address the constraints to sanitation business for effective service delivery. Households should be encouraged to consider the ‘cheaper’ and more feasible latrine technologies, and also adopt joint-resource mobilization strategies for their latrines. Programmes aimed at promoting improved sanitation, in a sustainable manner, should consider the heterogeneous needs and location of households as well as the reuse potential of excreta in agriculture. The choice of regulatory options for sustainable sanitation should be based on a comparative assessment of the trade-offs between effectiveness, ease of implementation and costs and benefits.
An Analysis of Yam consumption Patterns in Ghanaian Urban Communities
(2009-07-14) Aidoo, Robert
This study examined the major factors that drive changes in yam consumption patterns across income groups, seasons and urban centers in Ghana to inform food policy formulation. The study, among other things, sought to provide evidence on whether or not yam had become a luxury food commodity in Ghanaian urban communities. Special attention was also given to the question of whether household income allocation between males and females had any significant effect on yam consumption. Quarterly household panel data collected from four urban centers were used to conduct a complete demand system analysis by employing the Almost Ideal Demand system (AIDS) and Quadratic Almost Ideal Demand System (QUAIDS) models through the use of the Ordinary Least Squares (OLS) method. The study estimated yam expenditure elasticities for the pooled/aggregate data and the four different urban centers across different income groups to test Engel’s law. Results of the study showed that majority (>80%) of yam consumers in Ghanaian urban communities preferred white yam to yellow and water yams, and the most important reason for their preference was taste. Boiled yam (ampesi) was the most preferred yam product in Ghanaian urban centers followed by pounded yam (fufu). Rice was identified as the most important substitute for yam in urban communities. In a typical Ghanaian urban center, household food budget formed about 51% of the total household budget. Yam constituted about 12% of household at-home food budget and 13% of its away-from-home food budget. The shares of food budget that households allocated to yam generally increased during the peak harvest season and dropped during lean season across all urban centers in Ghana. Yam expenditure elasticity for the pooled sample was found to be inelastic (0.76), suggesting that yam is a basic food commodity in a typical Ghanaian urban center. Yam expenditure elasticity was lowest for Tamale (0.64), a less urbanized center, and highest for Accra (1.01), a more urbanized center. Generally, across urban centers, the study supported Bennett’s law which posits that households switch from less to more expensive calorie consumption as their incomes increase. However, in each particular urban center, Engel’s law was affirmed; yam expenditure elasticity was higher for low-income households and lower for high-income households. Yam expenditure elasticity was found to vary across seasons; yam was expenditure elastic during the lean season and expenditure inelastic during the harvest season. Women’s share of household income was found to be positively related to household yam budget share. Evidence from this study did not support the hypothesis of economies of household size with respect to household yam budget share when the pooled data was used for analysis. However, the hypothesis of economies of household size was supported in the seasonal consumption analysis where households were found to enjoy economies of size during the relatively yam abundant period of August to December and diseconomies of size during the lean season. The study showed that yam budget share was own-price elastic but expenditure inelastic. Urban households were more responsive to changes in yam prices than changes in household income, implying that the substitution effect is stronger than the income effect. The high price elasticity for yam budget share stresses the importance of food price changes for households, and it is important that households’ reactions are taken into account in the development of comprehensive agricultural and food policies in Ghana. Based on the findings of the study, recommendations have been made to help improve the Ghanaian yam sector and household food security in urban centers.
Anthill as a Resource for Ceramics
(JUNE, 2009 ) Adjei-Henne, George
The unavailability of ceramic raw materials and equipment for the firing of ceramic wares coupled with the lack of technical knowhow for the construction of kilns in Junior and Senior high schools have prompted this enquiry into, “Anthill as a resource for Ceramics.”The study has been undertaken to point out the usefulness of anthills in the teaching of ceramics in the Junior High and Senior High Schools. It is to assist the teachers and students to turn to the anthills in their own backyard to source for solutions to the problem of raw material and firing equipment. A comparative study of anthill materials and soils, have been made to find out the extent to which ants have modified the soils around them. Various tests were conducted to find out how useful anthill materials are so far as ceramic production is concerned. Exploratory study of the anthill structure was also conducted to find out to what extent it could serve as firing chambers and fire ports, flue holes, chimneys and other parts of the kiln. The results of the tests conducted indicated that many clay fabrication methods can be used to shape the soil from anthill. Different forms and wares were fabricated with the clay materials from the anthill. It also unveiled anthill as an insulative structure that retains heat in the semblance of an insulation brick kiln. Three types of anthills were modified to form three kinds of kilns and they were all fired successfully. It was also seen as a stable structure that can withstand a very high temperature without crumbling. Again it was revealed that the fuel consumption rate was comparatively low as only seventeen bundles of firewood were used for a batch whilst about thirty were used for a brick kiln of a similar volume. It was however recommended that further scientific investigations be carried out to find out the physical and chemical properties of the anthill. The method of construction of the anthill and the thermal regulation strategies used by the ants could also be studied and possibly adopted in the field of architecture.
Anti-inflammatory and anti-anaphylactic effects of trichilia monadelpha (thonn.) j. j. de wilde. ex oliv.pp (meliaceae) extracts in Rodents
(2013-08-04) Okon, Inemesit Ben
Trichilia monadelpha (Meliaceae) in Ghana and other parts of Africa, is used locally to manage various inflammatory and pain conditions.Three extracts(petroleum ather extrct,PEE, etthyll acetate extract, EthE, and ethernal extarct, EAE) obtained from this plant and evaluated pharmacologically................
Anti-inflammatory and ethopharmacological effects of an ethanolic leaf extract of Palisota Hirsuta K. Schum. (Commelinaceae)
(2009-08-09) Boakye-Gyasi, Eric
Leaves of Palisota hirsuta are used in Ghana and other West African states for various painful and inflammatory conditions. This study is aimed at evaluating the anti-inflammatory and ethopharmacological properties as well as toxicity profile of an ethanolic leaf extract of Palisota hirsuta using animal models. Preliminary phytochemical screening showed that the powdered leaves contained tannins, reducing sugars, flavonoids, steroids and terpenoids with traces of alkaloids. Effect of the extract on acute inflammation was assessed in the carrageenan- induced foot edema in 7-day-old chicks with diclofenac and dexamethasone as reference drugs. Pre treatment with the extract (30-300 mg kg-1; p.o.) significantly, inhibited foot edema in the chicks comparable to the NSAID diclofenac with maximal inhibition of 54.71±11.04%. Diclofenac and dexamethasone also dose- dependently inhibited carrageenan-induced foot edema. The anti-arthritic effect of the ethanolic leaf extract was assessed in the Freund’s adjuvant induced-arthritis model in rats. Palisota hirsuta extract (PHE) as well as dexamethasone and methotrexate, used as positive controls, showed significant dose-dependent anti-arthritic properties when administered prophylactically, curatively and also in combination therapy. PHE (30-300 mg kg-1) significantly reduced the arthritic edema in the ipsilateral paw with the highest dose used giving a maximum inhibition of 13.02±8.77%. PHE (300 mg kg-1) also significantly prevented the spread of the edema from the ipsilateral to the contralateral paw indicating inhibition of systemic spread. Dexamethasone (0.3-3 mg kg-1) and methotrexate (0.1-1.0 mg kg-1) significantly and in a dose dependent manner also inhibited polyarthritis edema. PHE in combination with methotrexate did not show significant effect. However there was a significant inhibition of arthritis in both the acute and the polyarthritic phases when PHE was combined with dexamethasone. Dexamethasone in combination with methotrexate caused the greatest inhibition of both phases with an extreme level of significance as expected. Overall, the present results demonstrate that PHE has anti-arthritic effect which could be similar to that exhibited by methotrexate. P. hirsuta (30-300 mg kg-1; p.o.) also dose-dependently decreased baker’s yeast induced fever in rats when Paracetamol (10-100 mg kg-1; p.o.) was used as the reference drug. The in vitro antioxidant properties of the extract were evaluated using the reducing power test; 2, 2-diphenyl-1-picrylhydrazyl hydrate (DPPH) radical scavenging assay and the lipid peroxidation assay. In all tests, n-propyl gallate was used as the reference antioxidant. The extract (0.1-3.0 mg ml -1) showed a reducing power potential (EC ; 133.7±7.59 mg ml-1) but was less than that of the reference antioxidant n-propyl gallate (EC 3.77±0.07 mg ml-1) in the reducing power test. The relative anti-oxidative activity in the DPPH de-colorization assay (defined by the EC ) was in the order: n-propyl gallate (8.02±0.01 × 10-4) > extract (1.77±0.40 × 10-1). The extract (0.1-1.0 mg ml-1) and n-propyl gallate (0.01-0.1 mg ml-1) exhibited a concentration dependent inhibition of lipid peroxidation. The rank order of potency (defined by ED in mg ml-1) was found to be: n-propyl gallate (1.31±3.00 × 10-2) > extract (4.29±0.95 × 10-1). These findings present the extract with potent antioxidant properties which may account in part for its anti-inflammatory and analgesic activities. In the analgesic assay, the leaf extract of P. hirsuta (PHE) (30, 100 and 300 mg kg-1 p.o) as well as morphine and diclofenac (positive controls), caused significant dose- dependent anti-nociceptive activity in all the pain models used. In the tail withdrawal test, PHE (300 mg kg-1) increased withdrawal latencies significantly by 43.83±11.62%. Also, PHE (300 mg kg-1) completely reversed the inflammatory- induced mechanical hyperalgesia with a maximum percentage effect of 154.79±15.84%. PHE significantly reduced the number of acetic acid induced writhing in mice. In the formalin test, PHE (10–300 mg kg-1, p.o.) caused a marked and dose-related inhibition of both phases of formalin-induced nociception. The anti-nociceptive effect exhibited by PHE in the formalin test was reversed by the systemic administration of the non-selective opioid antagonist, naloxone, the NO synthase inhibitor, NG-nitro-arginine methyl ester (L-NAME) and the ATP- sensitive K+ channel inhibitor, glibenclamide. However, theophylline a non- selective adenosine receptor antagonist did not reverse the effect. PHE, unlike morphine, did not induce tolerance to its anti-nociceptive effect in the formalin test after chronic administration and also morphine tolerance did not cross-generalize to PHE. Overall, the present results demonstrate that the central and peripheral anti-nociceptive of PHE may partially or wholly be due to the stimulation of peripheral and/or central opioid receptors through the activation of the nitric oxide-cyclic GMP- ATP-sensitive K+ (NO/cGMP/K+ATP)-channel pathway. As part of the present study, the ethopharmacological properties of the ethanolic leaf extract, in multiple behavioral paradigms of anxiety and depression— the open field test, the light/dark box, the elevated plus maze (EPM), the forced swimming test (FST) and tail suspension test (TST) was evaluated. P. hirsuta treated mice (30-300 mg kg-1) exhibited anxiolytic activity similar to diazepam in all the anxiety models used. PHE significantly increased the percentage number of center entries and the percentage time spent in the center of the open field. It also significantly increased the time spent in the lit area in relation to the time spent in the dark area of the light/dark box as well as significantly increasing open arm activity in the EPM. These effects were completely reversed in the presence of flumazenil (3 mg kg-1), a specific antagonist of the benzodiazepine site in the GABAA benzodiazepine receptor complex. The extract also dose-dependently reduced the duration of immobility in both the FST (ED50: 114.55±72.69 mg kg ) and TST (70.42±0.06 mg kg-1). Pretreatment with •-methyldopa (400 mg kg-1; 3 h; p.o.), to reduce brain NE and DA tissue content or reserpine (1 mg kg-1; 24 h; s.c.) for the disruption of vesicular storage of brain NE, DA and 5-HT tissue content or a combination of the two drugs to deplete both newly synthesized and vesicular components of NE and DA transmission attenuated the anti-immobility effects of both imipramime and the extract but not fluoxetine. Neither the extract nor the standard drugs used modified motor performance on the rota rod test at all doses tested. Collectively, these results suggest that the extract has anxiolytic and antidepressant-like effects in the models employed possibly by GABAergic activation and/or modification of monoamine transport and/or metabolism. In the toxicological study, there were no significant differences found in almost all of the hematological, serum biochemical parameters and organ/body weight ratio. No abnormality of any organ was found during histopathological examination. The results showed that the no-observed adverse- effect level (NOAEL) of P. hirsuta extract (PHE) was >3000 mg kg-1 body weight per day in rats, which can be regarded as virtually non-toxic. In conclusion, PHE had no overt organ specific toxicity and hence has a high safety profile in rats. Putting all together, these novel findings provide some pharmacological evidence and basis for the traditional use of the leaves of P. hirsuta in traditional medicine to manage various painful and inflammatory conditions.
Anti-Nociceptive Properties of the Ethanolic Extract Of Fruits of Xylopia Aethiopica (Dunal) A. Rich (Annonaceae) and its Major Constituent, Xylopic Acid
(2012) Ameyaw, Elvis Ofori
The fruits of Xylopia aethiopica are traditionally used to treat malaria, fibroid (uterine), fungal infection, rheumatism, arthritis, amenorrhea, boil, haemorrhoids and flatulence whilst the crushed seeds are applied topically on the forehead in the treatment of headache and neuralgia. TLC and HPLC analyses of the extract revealed the presence of several compounds. The isolated xylopic acid produced a single spot in a number of solvent systems including petroleum ether: ethyl acetate (1:9) and hexane: ethyl acetate (1:9) and a single peak in HPLC analysis certifying the level of purity of the compound The extract and xylopic acid exhibited antinociception in all the pain models used. In the acetic acid-induced writhing test, the extract (30 – 300 mg kg-1) (F3,28=14.37, P<0.0001) and xylopic acid (10 – 100 mg kg-1) (F3,28=20.56, P<0.0001) significantly reduced abdominal writhes induced with acetic acid in mice with the highest dose of the extract inhibiting visceral nociception by 98.8 ± 0.8%. The highest dose of xylopic acid also inhibited visceral nociception by 93.8 ± 1.4%. Morphine (1 – 10 mg kg-1) (F3,28=9.77, P=0.00016) and diclofenac (1 - 10 mg kg-1) (F3,28=4.04, P=0.0165) used as controls in this model similarly exhibited significant antinociceptive activities in this test. The extract (30 – 300 mg kg-1) (F3,28=6.93, P=0.0012) significantly attenuated mechanical hyperalgesia in the Randall-Selitto test with maximum possible effect of 110 ± 16.17% at the highest dose used. Similarly xylopic acid (10 – 100 mg kg-1) significantly (F3,28=4.86, P=0.0076) attenuated mechanical hyperalgesia with a maximum possible effect of 94.58 ± 21.6% at the highest dose in the same test. The extract and xylopic acid were both relatively more effective in the Hargreaves thermal paw withdrawal test, (extract: F3,64= 8.10, P=0.0338, xylopic acid: F3,64= 7.11, P=0.03) compared to the tail flick test (extract: F3,64= 6.47, P=0.045, xylopic acid: F3,64= 19.5, P<0.0001). For the acute and chronic musculoskeletal pain tests morphine was most efficacious. The extract was also more efficacious than xylopic acid. Xylopic acid was however more potent in reducing both the chronic muscle and knee pain whereas the extract was more efficacious in the chronic skeletal pain model. The extract, xylopic acid and pregabalin ameliorated vincristine-induced neuropathic pain. Common symptoms experienced by patients with neuropathic pain such as mechanical hyperalgesia, tactile and cold allodynia were measured using Von Frey filaments and cold water. The extract (F3,28=5.12, P=0.006), xylopic acid (F3,28=3.72, P=0.0229) and pregabalin (F3,28=5.92, P=0.0029) produced tactile anti-allodynia. Similar effects were observed in the Von Frey intermediate and mechanical hyperalgesia as well as cold allodynia tests. In the formalin test the extract and xylopic acid inhibited both neurogenic and inflammatory phases of pain. The antinociception of the extract, xylopic acid and morphine involved the inhibition of opioid, NO-cGMP, 5-HT3, adenosine and muscarinic pathways Further determination of the mechanism of antinociception of xylopic acid carried using binding assay revealed the binding of xylopic acid to μ-opioid receptors with an enhancement of endogenous opioid binding. Capsaicin-sensitive C-fibres-glutamatergic-nociceptive pathway was found to participate in the antinociception of extract and xylopic acid. Tolerance to morphine antinociception on the opioid receptors developed after chronic treatment for eight days but failed to develop to the extract and xylopic acid. Also morphine tolerance did not cross-generalize to the extract and xylopic acid. In order to elucidate the drug—drug interaction between xylopic acid/morphine and xylopic acid/diclofenac in combination administrations, isobolographic analysis was performed. The experimental ED50’s (Zmix) of xylopic/morphine combination were smaller than their corresponding theoretical ED50’s (Zadd) in both phases of the formalin test indicating synergism. Isobolographic analysis of xylopic acid/diclofenac combination carried out also indicated potentiation of the combination as the experimental ED50 lay below the line of additivity. The degree of potentiation calculated as interaction index indicated that the combination synergized to produce antinociception. In summary these findings provide scientific data for the use of the fruit of X. aethiopica in the treatment of painful conditions and co- administration of xylopic acid/morphine and xylopic acid/diclofenac may be said to be beneficial as their various side effects may be reduced due to lower doses used with potentiation of their therapeutic effects.

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