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- ItemA Modal Approach To Price An Option In Continuous Time(KNUST, 2018) Osei AntwiAverage 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.
- ItemAdoption 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 IbrahimaSoil 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.
- ItemAgricultural Land Use Change in the Lowlands of Southern Mali under Climate Variability(KNUST, 2023-07) Traore, AlouThis 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.
- ItemAn Integrated Approach To Buruli Ulcer Transmission Studies: From Aquatic Environments To Human Infection(KNUST, 2018-04) Charles QuayeBuruli 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.
- ItemAnalgesic and Anti-Inflammatory constituents of annickia polycarpa stem and root barks and clausena anisata root.(AUGUST, 2016) Kumatia, Emmanuel KofiClausena 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.
- ItemAn analysis of a peri-urban sanitation market and farmers’ perception on excreta reuse in agriculture in Dangme West District, Ghana(MAY 2016) Nimoh, FredThis 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.
- ItemAnticonvulsant and related neuropharmacological effects of a hydro-ethanolic whole plant extract of synedrella nodiflora (L.) gaertn (FAM:Asteraceae).(2011-07-19) Amoateng, PatrickSynedrella nodiflora (L.) Gaertn. (Family: Asteraceae) is an annual herb which grows to about 60-120 cm high and occurs throughout the West African region. In Ghanaian traditional medicine, the whole plant is used for the treatment of epilepsy. This study presents the anticonvulsant, sedative, muscle relaxant, antinociceptive, antioxidant, the effect on anxiety and the safety of a hydro-ethanolic extract of the whole plant of Synedrella nodiflora. Four murine models of experimental epilepsy were employed for the anticonvulsant screening of the extract, namely; pentylenetetrazole-, picrotoxin- and pilocarpine- induced seizure and penetylenetetrazole- induced kindling. The ability of the extract to cause sedation was investigated using the pentobarbitone- induced sleep test. The neuromuscular effects of the extract were also determined in vivo using the rota-rod test and in vitro with the chick biventer cervicis preparation. Moreover, formalin induced pain and acetic acid induced writhing assay were the tests employed to assess the antinociceptive effects of the extract. The antioxidant effects of the extract was also determined by measuring the total phenols, antioxidant capacity, 1, 1-diphenyl-2-picryl-hydrazyl (DPPH) scavenging assay, reducing power assay and inhibition of linoleic acid peroxidation. The elevated plus maze, the light/dark test and the Versamax animal monitor were used to investigate the effect of the extract on anxiety in rodents. The acute toxicity test was also done to assess the safety of the extract as herbal medicine. The extract, SNE, showed significant anticonvulsant effect against seizures induced by PTZ by dose dependent increase in both the onset of the myoclonic jerks and latency to myoclonic seizures and a reduction in the duration of seizures. However this effect was not significant compared to the vehicle treated group and not dose dependent. SNE significantly and dose- dependently delayed the latencies to myoclonic jerks and tonic-clonic seizures induced by picrotoxin. SNE also reduced the duration of seizures significantly. SNE also significantly reduced the total frequency of seizures. SNE, also, dose-dependently reduced the total duration of seizures induced by pilocarpine in the mice treated. SNE significantly suppressed the PTZ- kindled seizure at all the dose levels used. SNE (100-1000 mg kg-1) dose-dependently inhibited lipid peroxidation in the PTZ-kindled rats. SNE also, dose-dependently, increased the duration of sleep induced by pentobarbitone in mice. The ability of SNE to attenuate PTZ-, picrotoxin- pilocarpine- induced seizures, PTZ- induced kindling, enhanced sedation of pentobarbitone suggests the possible involvement of GABAergic, anti-cholinergic, or antioxidant mechanism(s). SNE at 1000 mg kg-1 produced a significant reduction in the time spent on the rota-rod at 24 rpm over the two-hour period thus suggesting motor impairment at this dose. Baclofen at 10 mg kg-1 significantly reduced the duration spent by pre-treated mice on the rota-rod. SNE also antagonised acetylcholine- induced contractions in the chick biventer cervicis preparation, thus a neuromuscular blocker. These results suggest a skeletal muscle relaxant effect by S. nodiflora possibly via centrally mediated mechanism(s) involving neuromuscular blockade. In the formalin-induced pain and the acetic acid- induced writhing, morphine and diclofenac were used as standard opioid and NSAID respectively. The hydro-ethanolic extract of S. nodiflora (100-1000 mg kg-1, p.o) and morphine (1-10 mg kg-1) dose-dependently decreased both phases of the formalin-induced nociceptive behavior. The antinociceptive effects of S. nodiflora (300 mg kg-1, p.o) on the first and second phases of formalin-induced pain were significantly blocked by caffeine but not by naloxone. In the acetic acid-induced writhing test, diclofenac and S. nodiflora significantly reduced the number of writhes dose-dependently. Also, the effect of the S. nodiflora (300 mg kg-1) was blocked by caffeine (3 mg kg-1) but the analgesic effect of diclofenac was significantly enhanced. The observed effects of caffeine on the central and peripheral analgesic effects of S. nodiflora in the formalin and acetic acid- induced writhing suggest the possible involvement of adenosinergic mechanism(s). The extract (0.1-3.0 mg ml-1 ) was found to contain phenolic compounds which could be responsible for the antioxidant properties. The extract also exhibited antioxidant properties by reducing Fe3+ to Fe2+ in the reducing power test, scavenged DPPH free radicals and effectively inhibited linoleic acid autoxidation. In the EPM paradigm, S. nodiflora extract (10-300 mg kg-1) exhibited anxiogenic-like activity by dose-dependently decreasing the number of entries into both the open and closed arms, no significant effect on the percent number of entry into the open arms and a decrease in the time spent in the open arm in comparison to the vehicle-treated group. Similarly, S. nodiflora extract (SNE) dose-dependently decreased the number of head dips and stretch-attend postures and the duration of grooming. In the LD test, SNE also exhibited anxiogenic-like effect by significantly and dose-dependently reducing the number of entry into the light compartment, the number of transitions and not significantly, the time spent in the light area. In the EPM and LD test, diazepam (0.1-1.0 mg kg-1), a reference anxiolytic drug, produced a directly opposite response to that exhibited by SNE. The extract, in the VAMS, decreased the locomotor activity of pretreated-mice dose dependently and significantly. SNE reduced the distance travelled and time spent at the center of the observation cage indicating an anxiogenic-like effect. The extract‟s ability to cause a general reduction in locomotor activity suggests sedative effects rather than anxiogenesis. Oral administration of SNE (1000-10,000 mg kg-1) yielded no mortality in the treated mice over a 24 h of observation. Thus the LD50 was approximated to be greater than 10,000 mg kg-1. Thus the extract can be said of as being less toxic. Also high protective indexes produce in the PTZ-, picrotoxin- and pilocarpine-induced seizures by the extract suggest that it has a safe therapeutic profile. In conclusion, the hydro-ethanolic extract of S. nodiflora has anticonvulsant effect in the acute and chronic seizure models of epilepsy used and indicates a possible GABAergic mechanism(s); exhibits central analgesic effect possibly mediated through adenosinergic mechanism and a peripheral anti-inflammatory activity and a potent antioxidant and free radical scavenger, a muscle relaxant and has anxiogenic-like and sedation effects.
- ItemAntiplasmodial compounds from Ghanaian medicinal plants(December 2015) Komlaga, GustavMalaria is a major public health challenge in Ghana, and many indigenes employ medicinal plants, beside orthodox medicines, to treat the disease. An ethnobotanical survey was performed in the Bosomtwi and Sekyere East Districts of Ghana to identify plants used locally to manage malaria. This was done in comparison with the plant ingredients in marketed herbal antimalarial remedies in the Kumasi metropolis. The survey inventoried ninety-eight (98) plant species; twelve (12; 12.2%) reported for the first time globally, and twenty (20; 20.4%) others for the first time in Ghana for the treatment of malaria. Twenty-three (23) locally available finished, often multi/polyherbal antimalarial products examined contained aerial or underground parts of twenty-nine (29) of the plants cited in the survey as ingredients. Twenty-two (22) of these products were registered by the Ghana Food and Drugs Authority; four (4) were included in the Ghana Health Service recommended herbal medicine list for treating malaria in Ghana. The aqueous as well as serially extracted organic solvents (petroleum ether, ethyl acetate, and methanol) extracts of five plants parts, selected based on their importance in the traditional treatment of malaria and lack of the appropriate data in the literature, were studied against the chloroquine-sensitive 3D7 and chloroquine-resistant W2 P. falciparum parasite in vitro. The plant materials included the whole of Phyllanthus fraternus, leaves of Tectona grandis, Terminalia ivorensis and Bambusa vulgaris, and root of Senna siamea. All the aqueous extracts showed notable antiplasmodial activity (IC50 < 10 µg/mL), except that of S. siamea, against 3D7 P. falciparum. Only T. ivorensis and S. siamea extracts showed activity against W2 P. falciparum (IC50 < 50 µg/mL). The extracts demonstrated high selectivity index (SI) for 3D7 P. falciparum (SI > 3.5) but very low SI for W2 P. falciparum. Resistance index (RI) was largely under 20. The organic fractions were equally active (IC50 < 50 µg/mL; 3D7 P. falciparum). The methanol extracts of the two most potent plant materials, the whole of P. fraternus and leaf of B. vulgaris, were subjected to phytochemical study to isolate and elucidate the chemical constituents, which were then assayed for antiplasmodial activity. The phytochemical study of the v methanol extract of P. fraternus yielded six compounds; Pf 1 to Pf 6 identified as the lignan, phyllanthin, and five securinega alkaloids namely nirurine, ent-norsecurinine, allo-norsecurinine, bubbialine and epibubbialine. This is the first isolation of allo - norsecurinine from a natural source and bubbialine from the Phyllanthus genus. The compounds displayed significant antiplasmodial activity against both 3D7 and W2 P. falciparum (1.14 ± 0.32 µM ≤ IC50 ≤ 59.00 ± 5.43 µM); ent-norsecurinine being the most active (IC50=1.14± 0.32 µM) and against the W2 P. falciparum. Only Pf2 (nirurine) and Pf1 (phyllanthin) displayed cytotoxicity (CC50 < 100 μM; HUVECs). This is the first report of the antiplasmodial activity of these compounds. Similar study of the methanol extract of B. vulgaris yielded 6 compounds, Bv1 to Bv6, identified as p-coumaric acid [(E)-3-(4-hydroxyphenyl) acrylic acid], cinnamic acid, dehydrovomifoliol [(E)-4-hydroxy-3,5,5-trimethyl-4-(3-oxobut-1-en-1-yl)cyclohex- 2-en-1-one], 3-oxo-α-ionol [9-hydroxy megastigma-4, 7-dien-3-one], loliolide [6- hydroxy-4, 4, 7a-trimethyl-5, 6, 7, 7a-tetrahydrobenzofuran-2(4H)-one] and tricin [5,7,4’-trihydroxy-3’,5’-dimethoxyflavone]. The six compounds are the first everreported isolations from B. vulgaris. All the compounds from B. vulgaris displayed significant activity against 3D7 (IC50 < 5 μΜ and W2 strains of P. falciparum (IC50 < 7 μM). Bv1 (p-coumaric acid) was the most active against 3D7 P. falciparum (IC50: 0.84 ± 0.90 μM) and Bv2 (cinnamic acid) the most active against W2 P. falciparum (IC50: 1.41 ± 0.38 μM). The compounds displayed no cytotoxicity (CC50 > 100 μM; HUVECs). This is the first report of the antiplasmodial activity of the six compounds. These twelve (12) compounds with remarkable antiplasmodial activity add to the library of natural compounds with antiplasmodial activity. This study has illustrated the potentials of Ghanaian medicinal plants as source of natural antiplasmodial compounds, and has justified the use of the plants in traditional treatment of malaria.
- ItemArt Therapy as an Intervention to Mitigate the Traumatic Effects Experienced by Victims of Human-Trafficking: A Case(KNUST, 2017-06) Aba-Afari, SarahHuman trafficking is a crime that has become a notorious phenomenon and iconic for contemporary slavery. It is premised on life distortions caused by wars, frequent interferences in democratic governance by the armed forces and natural disasters affecting the supply of essential commodities for which reason, many people suffer deprivation. This development creates opportunity for criminal gangs to exploit the vulnerable especially, women and children. In spite of the stringent laws at both national and international levels aimed at preventing the crime, several media reportages in Ghana revealed intermittent rescuing of human trafficked victims by the Ghana Police Service and some NGOs. The aims of the study were to identify and describe the causes of human trafficking in Ghana and their types and also to examine the existing social interventions available for victims of human trafficking and their effectiveness in dealing with the trauma associated with human trafficking. Additionally, the study aimed to determine how Art Therapy can be used to assist victims to recover from their trauma, since preliminary investigation indicated that these rescued victims exhibit series of traumatic dispositions at the police stations due to the trauma they suffer. The Qualitative and quantitative research designs were adopted to collect data on human trafficking. Case Study, Phenomenological Study, approaches were used together with interview, observation and questionnaire as instruments to determine trauma and its effects on these rescued victims. Whereas, purposive and snowball sampling techniques were used to select the population for the study. Content Analysis was also adopted to review the available social interventions and their effectiveness to deal with trauma of victims; whereas, Art Therapy was used to induce non-verbal communication of these voiceless, emotionally buttered and traumatised victims through drawing sessions and the artworks produced revealed the instabilities suffered in their emotional world. Through directed and non-directed themes in drawing, victims were observed to consistently, get releases as they shred various levels of traumatic dispositions and were healed emotionally and their attitudes resumed normal functioning. Art Therapy was identified to be effective in mitigating trauma of human trafficked victims. Their growth of healing was demonstrated through their artworks. Efficacy of Art Therapy in healing buttered emotions was revealed as these human trafficking victims were observed to regain their lost-selves and identity, which enabled their successful v reintegration. The methodologies applied facilitated the identification of causes and types of human trafficking prevalent in Ghana. Also the social interventions available for victims and limitations to their effectiveness in dealing with trauma associated with human trafficking were identified. The study has established Art Therapy as an effective intervention in healing the remote stressors that resulted into emotional instability of human trafficked victims. Further, the study outcomes indicated that Poverty, Religious Issues, Gender Roles and Abusive Parents were the major causes of human trafficking in Ghana. The study also revealed that the Social Protection division of the Ministry of Gender, Children and Social Protection was under resourced in terms of human and logistics so could not effectively perform its mandated duty of offering professional counselling services leading to reintegration as required by laws. The use of Art Therapy was identified to be effective, cost effective and a timely intervention in dealing with trauma experienced by human trafficking victims and it was observed to have multi utility effects in addressing trauma. For this effectiveness, cogent and logical conclusions and recommendations were made to the Government of Ghana and, the Ministry of Gender, Children and Social Protection to incorporate Art Therapy as a complementary intervention to counselling services so as to accelerate the healing process of human trafficked victims to normal functioning. The Government of Ghana was encouraged to recruit Art Therapists to offer services to victims.
- ItemArt Therapy in Special Needs Education: A Case of Autism in New Horizon Special School in Accra(KNUST, 2017-08) Esi Saah, GracevictoriaInclusive Education (IE) has become very necessary in education today, and the increasing prevalence of cases such as autism and the fear of autistic individuals missing out on quality education to assist them attain their full potential as they get integrated into society cannot be denied. Unfortunately, the Special Educational Needs Policy of Ghana does not include a curriculum for teaching autistic children. Autism schools and teachers in Ghana are compelled to use curriculums that may not suit the needs and learning styles of autistic learners or adopt curriculums of other jurisdictions. This study investigated how autism teachers teach and autistic learners imbibe instructions, and the therapies used at the New Horizon Special School at Cantonments in Accra, Ghana. The study also explored the world and characteristics of autistic learners and how they function, and how the inclusion of Art Therapy as an intervention may be helpful in teaching autistic learners at the New Horizon Special School, as studies have proved its efficacy in this regard. The research being qualitative was quasiexperimental and descriptive in nature, and adopted observation and interview as data collection instruments. These helped to identify and describe the characteristics of autistic learners at the school, the instructional strategies and existing therapies employed in the school, and their influences or impact on the education of Numeracy and Literacy. It also facilitated the description of Art therapy sessions, processes and outcomes on the behaviour and coping skills of autistic pupils were also described. Purposive, cluster and simple random sampling techniques were adopted for the study; sampling 21 participants comprising 9 autistic pupils each in the senior and junior autism classes, 2 autism teachers and 1 sensory coach. The study identified art therapy as a worthy inclusion in the education of autistic individuals. Therefore, a series of art therapy sessions were conducted for autistic learners in groups and individually during which their behavioural differences were observed. The art of the autistic learners was interpreted for the development of an art therapy inclusive teaching model for autistic individuals. The model was pre-tested and was found to enhance the communication and personality of the autistic learners while improving classroom management. Typically, aggressive and hyperactive pupils had better control of their emotions through art therapy in Numeracy and Literacy education. Therefore, Art therapy was proposed as a worthy intervention in the education of autistic learners at New Horizon Special School
- ItemAsante 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.
- ItemAspects of the ecology of noack’s roundleaf bat (Hipposideros Aff. Ruber) in Ghana(2014-07-20) Nkrumah, Evans EwaldThe roost of bats in five caves in the central parts of Ghana were investigated. A total of 10,226 bats belonging to nine species were mist-netted within two years. There was a significant difference in species composition of the caves. The Noacks’s roundleaf bat, Hipposideros aff. ruber was found to be the most dominant species roosting inside the cave and some aspects of its ecology were further investigated. The flight activity of Hipposideros aff. ruber was limited to certain periods of the night at Kwamang cave one while it was uniform at Kwamang cave two. The estimated mean home range size of this species using radio-tracking was thirty-six hectares with a foraging range of 1.2 km. There was no significant difference in the home range sizes of the males and females. Hipposideros aff. ruber used 50% of its home range as the foraging area and 2% as the core area. Pregnant females had smaller home ranges and foraged not more than 0.2 km away from the roost cave. Hipposideros aff. ruber used all available habitats around its roost but strongly preferred to forage in fallow lands ahead of other habitats. This bat used tree farms such as cocoa as flight paths to commute between roost caves and foraging areas and exhibited a trimodal activity pattern foraging at dusk, midnight and dawn. Hipposideros aff. ruber is a strong flyer commuting over longer distances. A three kilometre radius around its roost should be included in the protection of its home range. In highly impacted agricultural landscapes, fallow lands are recommended as conservation units to support this bat. In such landscapes, provision of canopy trees as flight paths is recommended to allow them to commute between roost and habitats that support higher prey densities
- ItemThe attitudes and perceptions of students about the study of english grammar: the case of selected senior high school students in northern region(2015-05-22) Akurugu, Brigandi MichealThe poor quality of English, both spoken and written, of Ghanaians in general, and of our students in particular, has become a source of worry to many well meaning educationists, parents and the general public. Several reasons have been given for the falling standards. Included among them are reading habits, poor teaching, inadequate library facilities, decline in the teaching of grammar and the de-emphasis of the mother tongue as the medium of instruction. There are those who believe that the use of the mother tongue at the basic level of education helps the learner to relate similar grammatical concepts in the L1 to those of the English Language. Much as the aforementioned could be said to be accountable, there is a fundamental phenomenon that acts as the underlying cause of the problem. The role that perception and attitude of the learners plays in the acquisition of skills in English has, over the years, been terribly ignored. The perception of students, teachers, policy makers, and the larger community, which includes parents, has played a considerable role in bringing about the fall in the standard of English. This study investigates the extent to which the fall in the standards of English could be attributed to attitudes and perceptions. The study has revealed that a serious disconnection exists between the needs of students and the solutions that are being used to raise the standard of English Language among learners. The study also reveals that, in most cases, parents, teachers and policymakers cannot escape blame for the problem either for their action or inaction regarding the promotion of the learning of the language. Though the study may have identified other reasons for the decline in the standards of English, the study focuses, to a large extent, on the very attitude and perception of the learner. It has suggested ways of developing positive perceptions and attitudes v towards the language. These suggestions include sound approaches to the teaching and learning of the language. The approach is carved in a manner that would make English more attractive to learners thus leading to attitudinal and perceptual change, which in turn would lead to enhanced performance of learners in English.
- ItemComparative Clinical Study of Mist Amen Fevermix and Edhec Malacure: Two Polyherbal Products used for the Treatment of uncomplicated malaria in Ghana against Artemether/Lumefantrine(2020-11) Turkson, Bernard Kofi; https://orcid.org/0000-0002-4990-7725The use of herbal medicinal products for the treatment of malaria an infectious and a life threatening disease, has increased globally. However, inadequate scientific studies, questions about the quality, safety and efficacy of such herbal products have been raised. On the other hand, the reduced sensitivity of the malaria parasites to artemisinin-based combination therapies is also of concern. There is therefore the need for new antimalarial medications including those from alternative sources such as herbal medicinal products. In this study, methods for the quality control of Mist Amen Fevermix and Edhec Malacure, two polyherbal antimalarial products used in Ghana for the management of uncomplicated malaria was undertaken. The development of the quality parameters for the test samples was based on phytochemical, physicochemical, chromatographic and spectroscopic methods. The set parameters were found to be sufficient to evaluate Mist Amen Fevermix and Edhec Malacure, and can be used as reference standards for the quality control purposes. Qualitative phytochemical screening and fingerprinting were undertaken based on standard analytical methods. The antiplasmodial activity was assessed in vitro by using field isolates of Plasmodium falciparum with SYBR® Green assays to measure parasite growth inhibition. Thermo Elemental M5 Atomic Absorption Spectrophotometer (AAS) fitted with Graphite furnace and an auto sampler was used to determine the heavy metal contents of the herbal products. The herbal samples were evaluated for microbial load by using the appropriate culture media. In vivo antiparasitic activity in mice was assessed using the Rane’s curative method using ANKA strain of Plasmodium berghei parasites. A comparative clinical study was done to assess the safety and effectiveness of the test samples at the Tafo Government Hospital, Kumasi after Committee on Human Research, Publication and Ethics approval. Male and female patients aged 15-45 years with clinically established malaria were treated with Mist Amen Fevermix and Edhec Malacure, at the specified doses of 45 mls (0.1063 g) and 30 mls (0.0521 g) three times daily after meals for three days. Basic phytochemical screening of the two products indicated the presence of the following phytochemicals: alkaloids, saponins, tannins, phytosterols and flavonoids. From the data, it was established that Mist Amen Fevermix and Edhec Malacure complied with the pharmacopoeial standards after testing for microbes. The following heavy metals were present in Mist Amen Fevermix and Edhec Malacure: Fe, Ni, K, Zn, Hg, Cu, Mn, Cr, Cd, Pb, Fe, Cu, K and Na. Ni was below detectable limit in Edhec Malacure. The phytochemical screening of the products revealed the presence of alkaloid flavonoid, tannin, steroid and saponin. The HPLC method was validated for linearity, limits of detection and quantification, precision and accuracy. The test products were found not to have been adulterated with lumefantrine, artemether and quinine. The test herbal products showed in vitro and in vivo antiplasmodial activities against Plasmodium falciparum and Plasmodium berghei parasites. Inhibitory concentration (IC50) values for Edhec Malacure was 70.89 ng/ml and that of Mist Amen Fevermix was 112.5 ng/ml. Edhec Malacure suppressed 76.17% of parasitaemia while Mist Amen Fevermix suppressed 69.03% of parasitaemia. Edhec Malacure demonstrated curative chemo suppressive potentials of 80.93% at the dose of 2.234 mgkg-1 and Mist Amen Fevermix % suppression was 69.03% at a dose of 4.56mg/kg-1. Both products demonstrated antiplasmodial activity in human red blood cells. The clinical evaluation of the test samples showed that Mist Amen Fevermix exhibited a statistically significant difference between the mean malaria parasite load recorded at the first visit and those recorded at the second visit, t(23) = 4.59, p =0 .000. Similarly, there was a significant difference between the mean parasite count recorded on the second visit and the third visit, t(6) = 1.49, p =0 .187. No difference were recorded for the third and fourth visits t(3) = 1.00, p =0 .391. Edhec Malacure also exhibited a significant difference in efficacy between the mean malaria parasite count recorded at the first visit and those recorded at the second visit, t(26) =3.77, p =0 .001. Similarly, there is a statistically significant difference between malaria parasite count at the second visits and third visits, t(16) = 1.74, p =0 .100. This shows the significant effectiveness of the products. Kidney and liver panel as well as full blood count and vital signs were within normalviii reference range at the end of the 28-day study and thus established the safety of Mist Amen Fevermix and Edhec Malacure in the treatment of uncomplicated malaria. The results support claims that Mist Amen Fevermix and Edhec Malacure may be useful antimalarial agents. This study has demonstrated the in vitro and in vivo antiplasmodial activities of Mist Amen Fevermix and Edhec Malacure, and suggests that, the products have promising antimalarial activity. The in vivo findings showed that Mist Amen Fevermix and Edhec Malacure are relatively safe for oral administration at doses tested. In addition, the study supports the use of Mist Amen Fevermix and Edhec Malacure, two polyherbal products for the treatment of uncomplicated malaria. Both products achieved a comparable clinical treatment outcome to the reference control medication artemether/lumefantrine.
- ItemCompatibility of Jatropha Curcas in an Agroforestry System(2015-04-20) Abugre, SimonJatropha curcas is gaining importance as a potential biofuel crop in Ghana. Already skeptics are talking about the impact of the crop on food crops. It is important that the compatibility of J. curcas in agroforestry systems is investigated to provide answers to some of the potential problems being advanced. Experiments were conducted to determine the compatibility of J. curcas on the growth and yield performance of Zea mays. To determine the growth and yield of Z. mays under J. curcas hedgerows, an experiment using a Randomized Complete Block Design (RCBD) with three hedgerow spacings of 2 m x 1 m, 3 m x 1 m, 4 m x 1 m of J. curcas and a control (No hedgerow) was conducted. This was replicated 3 times. The results of the study showed that J. curcas spacing had no significant effect (P ≥ 0.05) on plant height, plant diameter, number of leaves and number of nodes/plant of maize in the first year. In the second year, however, increases in plant height of 17.19%, 22.39% and 23.38% were realized for 3 m x 1 m, 4 m x 1 m and the control (No hedgerow) respectively with respect to 2 m x 1 m. Diameter at first node however, increased by 19.69%, 16.87% and 18.46% for control, 3 m x 1 m and 4 m x 1 m respectively with respect to 2 m x 1 m. Maximum grain yield of maize was 4.47 tons/ha in the first year at the control treatment, which differed significantly from the 2 m x 1 m, 3 m x 1 m, 4 m x 1 m treatments. Chemical properties of the soil did not record any significant decline after two years of cultivation for pH, organic carbon, total nitrogen, organic matter, exchangeable cations, total exchangeable bases, exchangeable acids and base saturation. The highest Land Equivalent Ratio (LER) was recorded at 4 m x 1 m for both years, making it the most suitable plant spacing for J. curcas with maize while the highest economic returns were obtained at 4m x 1m and 3m x 1m spacing. The influence of storage period, fertilizer and spacing on the growth and yield of J. curcas propagated from seed were evaluated in a second experiment using two different designs. Seeds of J. curcas were stored for 1 to 12 months, sown on beds in a RCBD,replicated four times and their viability and germination energy tested. The results showed a progressive decline in germination from 98% after one month to 52% when stored for 12 months. The highest germination energy was obtained during the first two months of storage. Fertilizer and spacing effects were also evaluated in a split plot design in RCBD and replicated three times. Three plant spacings (D1=1m x 1m; D2=2m x 1m; D3=3m x 1m) and two fertilizer application levels (F0: 0kgNPK/ha, F1: 150kgNPK/ha) were used. Fertilizer and spacing interaction did not significantly (P ≥ 0.05) affect yield components of J. curcas. The fertilizer treatment however, had a significant effect on yield components and increased seed and fruit yield by 56.4% and 51.75% respectively. Spacing did not significantly affect seed yield. A third experiment on the variation in seed sources of J. curcas and polybag size on the growth of seedlings was laid out using a split plot design in RCBD with 3 replicates. The results showed significant variation in seed weight from the various seed sources but no differences in seed length and seed width. Seedling growth of J. curcas was highest when larger polybag size was used, however, it did not differ significantly from medium polybag size. Based on the results obtained medium polybag size would be ideal for raising seedlings. In a fourth experiment the decomposition trend of J. curcas leaves was assessed by placing 80 g fresh leaves in a 0.30 m x 0.30 m nylon litter decomposition bags of 2 mm mesh size under closed and open canopies. The total quantity of litter produced in a year at different spacings were 2.27 ton/ha, 1.10 tons/ha and 0.79 tons/ha for 1 m x 1m, 2 m x 1m and 3 m x 1m, respectively. The month of November had the highest litter fall (508.8 kg/ha) for 1 m x 1 m. J. curcas under open canopy had 97-99% of leaf litter decomposing by the end of the experimental period and a half-life of 25 days. Open canopy had the highest decomposition constant (k) of 0.020. In a final experiment the effect of aqueous extracts from leaves and roots of J. curcas on four traditional crops (Phaseolus vulgaris, Zea mais, Lycopersicon lycopersicum and Abelmoschus esculentus was examined. Aqueousextracts at concentrations of 2%, 4%, 6%, 8% and 10% applied to the test crops affected all the crops. Extracts at higher concentrations of J. curcas had a strong inhibitory effect on germination, radicle and plumule length of all the test crops. The inhibitory effect suggests the presence of allelochemicals that could inhibit the growth of the crops. Generally, it can be concluded that J. curcas is compatible with maize in an alley cropping system but closer spacing of planting J. curcas can reduce maize yields. Management practices such as pruning could be applied to get the optimum benefit from the system.
- ItemConstruction of a Texturing Device for Managing Surface Defects of Locally Produced Vegetable Tanned Leather(2017-11) Sefaah Tabi, JenniferLeather surface quality is very vital when it comes to leather artefact production. Leather surface defects reduces the surface quality of leather thereby affecting the value of the leather products on the market. In view of this, this research emphasizes the need to utilize leather surface defect management techniques which is keen as it tends to improve the surface quality of the leather and its products at large. The study identified various defects and management methods which are currently implored by leather users to manage surface defects. The research further designed, produced and tested the efficacy of an alternative leather defect management device. This intervention was adopted based on the assertion made by Allman (2012-2016), Deines (2014) and Anon (n.d.) that texturing contributes quality to surfaces and their appearance by improving and correcting surface imperfections. By employing the qualitative methodology to address the problems identified the research used arguments and suggestions to advance the fact that texturing truly improves and corrects surface imperfections in some leather defects. Defects which could be corrected include grain loosening and wrinkled surface defects. Defects like holes and patched remained as they are after the intervention. Cuts, molds, and parasitic infections were slightly nullified. The study further recommended other researchers to take it upon and develop different textures to test effectiveness of varying textures for various leather surface defects.
- ItemThe Contributions of International Development partners to rural poverty reduction in Ghana: a case study of the International Fund for Agricultural Development (ifad) and small-holder farming in the Sekyere-West District, Ashanti Region(2009-07-15) Asamoah K., KennedyAlthough available statistics in recent years reveal a decline in poverty in Ghana, many people still live below the poverty line. Rural small-holder food crops farmers are the most vulnerable groups affected by poverty. They have limited access to productive assets, most especially micro-credit. Many international development organisations have emerged to help alleviate some of the problems encountered by the rural poor. The International Fund for Agricultural Development (IFAD) as an international development partner in Ghana, has been working with small-holder farmers in the Sekyere West District since 2000 with the aim of improving rural income, reducing vulnerability, ensuring rural household food security and generally improving the well-being of the rural poor. This thesis examines the effects of IFAD’s project on food crops production, employment as well as income levels and the general welfare of small-holder farmers in the District. A random sample size of 240 IFAD assisted farmers in the District was used to undertake the study. Cross-sectional data covering the farming years (2000 – 2004) were elicited from the farmers through structured interviews and focus group discussions. Information such as sources of financing, farm input, farm size, crop yields and income levels were sought from the farmers. The study revealed that IFAD, as enshrined in its policy statement of ensuring gender equity in the distribution of its resources/assistance (IFAD, 2000), equal number of male as that of female small-holder farmers (approximately 50-50 respectively) were selected in the District to participate in the project. The study also showed that majority of the farmers interviewed depended on farm income as their main source of subsistence. Micro-credit provision was particularly seen as the most important factor influencing food crops production in the District. The study also showed that the effective training and monitoring activities of IFAD field staff ensured that resources given out to the farmers were not misappropriated. The study showed that the project registered a high food crops production rate as well as a high loan repayment rate of the farmers. Furthermore, the study revealed that the average income of beneficiary farmers increased considerably over the project period due to the good marketing strategy introduced by the project. Based on the findings of the study, it was recommended that the government should adopt and replicate the IFAD intervention scheme in all the other districts in Ghana since the project could have a multiplier effect on the livelihood of the rural poor especially the small-holder farmers.
- ItemControl of pregnancy-associated malaria through community involvement in rural Ghana(2009-6) Bam, Victoria BubunyoMissing Page
- ItemCrops-Livestock Integration as a Resilience Strategy to Climate Change in Burkina Faso(2023-07) Sanou, Charles LamoussaThis study titled addressed a topical issue of climate change and its impacts on farmers' livelihoods and the role that an integrated crop-livestock system can play in building resilient farmers and agricultural systems. The research first of all analysed historical climate (rainfall, minimum and maximum temperature) trends across three climatic zones Sudan (Dano), Sudan-Sahel (Niou) and Sahel (Dori)) at annual, seasonal and decadal scales. Climates indices computation was done using the package ClimPACT2 GUI in R software. Annual and seasonal climate were compared using the independent t-test. Decadal climate indices were subjected to a Principal Component Analysis (PCA). The research also analysed the susceptibility or sensibility of crop production and livestock health to climate change. Thirdly, the research developed and/or updated measurement tool known as Crop-Livestock Integration (CLI) indicators for a holistic characterisation of integrated croplivestock system. These indicators were developed based on the information from 589 farmers’ households and secondary data. Above ground, data were collected from 4,733 trees over a total land area of 243.2 ha (80.1 ha, 78.8 ha and 84.3 ha in Sudan, Sudan-Sahel and Sahel zones, respectively). Due to the Sahel zone's insecurity, soil data could be collected only within Sudan and Sudan-Sahel zones. In total, 120 composite soil samples were collected for this purpose and 240 other samples for soil bulk density determination. Results revealed changes in climate conditions, more pronounced in temperature variations than in rainfall. In the Sudan-Sahel and Sahel zones, a re-wetting trends was observed over the last decade supporting the re-greening hypothesis of the Sahel. Despite some positive effects of the climate indices, crop failure was the major impact of climate pejoration across iv zones. Similarly, livestock health was majorly negatively affected by climate deterioration though the resurgence of diseases due to climate change. Climate indices could explain 23.0 - 50.2 % of the variations in crop yield and an increased cases of livestock diseases occurrence by 1-9.4 units due to the deterioration in climate conditions across climatic zones. Changes in climatic conditions may also induce microbial proliferation and host susceptibility to result in the emergence, redistribution, and changes in the incidence and intensity of pest infestations. The study concluded that crop-livestock integration is underperforming in Burkina Faso and can be improved. Majority farmers (91.6 %) in the Sudan-Sahel zone are practising full crop-livestock integration, unlike the Sahel (62.3%) and Sudan (48.2%) zones. However, only 14.8%, 10.5% and 5.1 % showed the effectiveness of integration in the Sudan-Sahel, Sahel and Sudan zones, respectively. CLI was comparatively more effective in Sudan-Sahel (65.9±32.0 %) than Sahel (44.9±29.5 %) and Sudan zones (35.6±35.0 %). Integration indicators were significantly associated with farm emissions, productivity, biodiversity and soils nutrients. CLI is also a tree-based system with high sequestration potential that could significantly counterbalance the whole system emissions. However, the coverage of fodder needs is negatively associated with soils nutrients content indicating field nutrient mining if an appropriate scheme of nutrient return to the soils as manure is not set. An adequate combination of CLI components offers an opportunity to build resilient farming systems in Burkina Faso to adapt to the changing climate.
- ItemDehydration Characteristics, Quality Evaluation And Consumer Assessment Of Solar Dried Tomato.(KNUST, 2018-11-29) Mavis Owureku AsareTomato (Lycopersicon esculentum) is an important vegetable used in cooking most local foods in Ghana. At the peak season of harvesting, high loses are incurred because of the absence of facilities to process fresh tomato and extend the shelf life. Solar drying has been proven to be a more efficient and low cost method of enhancing quality and adding value to tomato and other vegetables. However, there are concerns on the usage, functionality and sensory appeal of the dried products by consumers. In this study a natural mixed mode solar dryer suitable for drying tomato was adapted and used to investigate the dehydration characteristics, quality and consumer acceptability of the dried products. An initial baseline survey was conducted using semi structured questionnaires administered to 395 randomly selected respondents in the Accra Metropolis. Information was obtained on the demographics, consumption pattern, knowledge and acceptance of tomato processing technologies and assessment of quality attributes of tomato. The efficiency of a passive solar dryer was evaluated and used in the processing of fresh tomato to powder. The processing involved the pre-treatment of 6mm slices of fresh roma tomato by dipping in (a) 1% potassium metabisulphite solution (b) 1 % ascorbic acid solution (1:1) for 10 minutes respectively. Untreated tomato slices served as control. Samples were then dried in the passives and in the open sun, with the open sun drying serving as control. The moisture content, moisture ratio and dehydration rate of solar dried tomato was assessed. The quality of dried tomato was assessed for their physicochemical, nutritional and microbiological characteristics. Physicochemical analysis involved determination of pH, total titratable acidity, dry matter, ash, tristimulus colour, total soluble solids, water activity and moisture. Nutritional quality was assessed for lycopene, beta-carotene, total carotenoid acids using high performance liquid chromatography (HPLC) procedures. Flowability, smoothness and compressibility (or packing porosity), particle size and shape distribution of the tomato powder was determined using a Morphologi G3-ID. Scanning electron microscopy of pre-treated solar and sundried tomato samples were imaged with an FEI Quanta 3D FEG scanning electron microscope. Quantitative Descriptive Analysis (QDA) was carried out to compare the sensory descriptive profiles of solar dried tomato powder with existing products on the market using a trained descriptive panel of nine (9). Home Use Test (HUT) was conducted using a trained panel to assess the acceptability of solar dried tomato powder in local foods. The results showed that, most consumers (74%) preferred tomato powder that was conveniently packaged to retain the characteristic intense taste and the flavour. The first day dryer efficiency of 24.2 % facilitated the drying process of tomato (final moisture content of 12-14%). The ash content was slightly higher in the sun-dried tomato (9.3 -10.14 %) compared with the solar dried tomato (9.4 - 9.68 %), an indication of potential contamination with extraneous materials from the environment. Water activity for solar dried tomato powder were significantly lower (0.35 - 0.38) than sundried tomato powder (0.53 - 0.57) and water activity lower than 0.6 is considered microbiologically safe for storage. Lower tristimulus colour L* values (37.81 - 40.31) observed for sun-dried tomato samples indicated that these samples were darker in colour than the solar dried samples with L* values (50.35 - 46.44). Aerobic mesophile counts were lower in solar dried (3.90 CFU/g) tomato pre-treated with potassium metabisulphite compared with sun-dried samples (4.85 CFU/g). Sulphur dioxide content (740.8 ppm) of solar dried tomato pre-treated with potassium metabisulphite was lower than the maximum legal limit (2000 ppm) recommended in fruits and vegetables, indicating its safety for human consumption. A strong, negative correlation between sulphur dioxide 740.9 ppm concentration and microbial load was observed for solar dried tomato. QDA results indicated a strong tomato aroma intensity (scored 127 out of 150) for solar dried tomato powder with the market samples having an extremely low intensity score of 0.7 out of 150 for tomato. Sensory profiling of the two products differed extremely in aroma, appearance and texture. Sensory characteristics of reconstituted solar dried tomato powder was similar to that of fresh tomato and tomato paste (two products commonly used in cooking). It had a very coarse appearance and texture (as predicted by the particle size distribution and shape profile and parameters of convexity and circularity) and a strong boiled/cooked aroma compared to tomato paste which had a higher intensity of red colour, metallic and stewed tomato concentrate aroma and flavour. Most of the participants used tomato powder to prepare local dishes such as “jollof “rice, tomato stew and light soup because of the good swelling characteristics of the product. The mixed mode solar dryer developed in this study was efficient in processing tomato powder which appealed to consumers and had varied uses in food production. The dryer has the potential of enhancing post-harvest loses, extending the shelf life of tomato and creating an alternative processing method which is simple and convenient.
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