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- 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.
- ItemHousehold Energy, Coping Strategies and Health Effects in the Bongo District of Ghana(2009-07-14) Odoi -Agyarko, Aba ObrumahCurrently millions of people around the globe rely on wood as a source of fuel for cooking. Although this situation not only pertains to impoverished rural communities, it is within these communities and in developing countries like Ghana that this is occurring the most. The burning of wood in open fires is causing a number of health problems but is also deteriorating for the rural household economy as well as for the local and global environment. Women and children are the main groups exposed to the indoor smoke produced while cooking. Illnesses as a result of this exposure take millions of lives every year. This thesis looks into the relationship between rural household energy consumption patterns, coping strategies and health effects for domestic cooking in the Bongo district in the Upper East Region of Ghana. Several methods including household survey; focus group discussion and key informant interviews were employed to collect data at household and individual levels. The methods involved queries on several aspects of household energy consumption. The survey of household energy consumption pattern was carried out in fifteen communities comprising of 625 households between January-April 2006. The households surveyed covered heterogeneous population belonging to different income, educational and social groups. Daily average concentrations of respirable particulates and carbon monoxide from woodsmoke in 45 rural homes selected through stratified random sampling from the Bongo district in Ghana was also quantified using UCB Particle Monitors. CO was measured with Onset HOBO Loggers. Graphical, cross-tabulation and multinomial logistic regression methods are applied to data drawn from Household Survey. The results indicated that there was more availability and utilization of solid biomass fuels as energy resources in domestic sector as compared to the commercial fuels. Crop residues, firewood and Charcoal were found to be the three main fuels used for cooking, though LPG was also used along with biomass fuels. But complete conversion to cleaner fuels has not taken place yet even in households that has been using LPG for many years. Income was an important factor determining the choice of fuel for cooking, but there were some socio-cultural factors which were equally important in making fuel preferences at household level. The use of biomass fuels; from it collection to combustion also has impacts on the health of the user. Result from the woodsmoke monitoring shows that the values of respirable particles (PM2.5) ranged from 0.05–6 _g.39mg/m3 and 2.90- 45.60ppm for CO. Both PM2.5 and CO concentrations were well above both the World Health Organisation 24-hour Guideline and Interim Targets. Observed health effects from the collection and use of biofuels included eye discomfort, headache, backache, coughing, skin irritation, stiff necks and chest pains. Extrapolation of diseases with PM concentration showed that households were in a higher risk of being infected with respiratory diseases from the use of biomass fuels. This observation confirms with the self-reported symptoms associated with biomass fuel use where respiratory diseases dominated (cough, wheezing, shortness of breath, eye irritation). Considering that traditional biomass will likely continue to be the most popular cooking fuel in rural areas of the district in the near future, and that households can achieve considerable welfare gains from improvement in stoves and kitchen ventilation, the analysis suggests that the government should consider reviving the improved stove program with a new advanced stove strategy coupled with conducting advocacy campaigns on how to improve kitchen ventilation.
- 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.
- ItemQuantum Mechanical Studies of the Mechanisms of Some Transition Metal Organometallic Reactions(2009-07-18) Tia, RichardThe mechanistic pathways of three organometallic reactions, namely the oxidation of ethylene by chromyl chloride leading to the formation of epoxide, 1,2-dichloroethane, 1,2-chlorohydrin, acetaldehyde, and vinyl alcohol precursors; the olefin metathesis reaction involving ethylene and 20 metal methylidene Cl4MCH2(M=Cr, Mo, W, Ru, Re) and metal oxo-methylidene Cl2(O)MCH2(M=Cr, Mo, W, Ru, Re) complexes; and the transition-metal-assisted formation of 1,2-dinitroso complexes of cobalt and its congeners have been studied using hybrid density functional theory at the B3LYP/LACVP* level of theory. The formation of the epoxide precursor (Cl2(O)Cr-OC2H4) was found to take place via initial [2+2] addition of ethylene across the Cr=O bond of CrO2Cl2 to form a chromaoxetane intermediate, as opposed to [3+2] addition across the two Cr=O bonds of CrO2Cl2 as suggested in earlier studies. The hitherto unexplored pathway involving initial [3+2] addition of ethylene across the Cr=O and Cr-Cl bonds of CrO2Cl2 was found to be more favorable than the [3+2] addition across the two Cr-O bonds of CrO2Cl2. The formation of the 1,2-dichloroethane precursor was found to take place via [3+2] addition of ethylene across the two Cr-Cl bonds of CrO2Cl2. The 1,2-chlorohydrin precursor was also found to originate from [3+2] addition of ethylene across the Cr-O and Cr-Cl bonds of CrO2Cl2 as opposed to [2+2] addition of ethylene across the Cr-Cl bond. Also the vinyl alcohol and acetaldehyde precursors were found to arise from a direct attack of one of the carbon atoms of ethylene on an oxygen atom of CrO2Cl2 through a triplet intermediate. In the reactions of Cl4MCH2(M=Cr, Mo, W, Ru, Re) with ethylene it was found that the formation of the metallacyclobutane through formal [2+2] cycloaddition, a key step in the olefin metathesis reaction according to the Herrison-Chauvin mechanism, is a low-barrier process in each of the complexes studied. It was also found that the active species for the formation of the metallacyclobutane is a carbene complex and not a carbenoid complex. One key factor was found to be responsible for the difference in metathesis activity in these complexes: the stability of the carbenoid complexes relative to the carbenes. In Cr and Ru, the carbenoid complexes are more stable than the carbenes and thus Cl4CrCH2 and Cl4RuCH2 are likely to exist in the lower- 21 energy carbenoid Cl3MCH2Cl form as opposed to the carbene Cl4M=CH2 form. This is likely to deplete the reaction surface of the active species of the process, making Cl4MCH2(M=Cr, Ru) not suitable for olefin metathesis. This suggests that whereas Cl4MCH2 (M = Mo, W, Re) may catalyze olefin metathesis, Cl4MCH2 (M = Cr, Ru) may not. The W and Re complexes have been found to have greater metathesis activity than the Mo complex. In the Cl2(O)MCH2 (M=Mo, W, Re) complexes the metathesis reaction has favorable energetics and is found to be more feasible than the side-reactions studied while in the Cl2(O)MCH2(M=Cr, Ru) complexes, the olefin metathesis is found to be less favorable than the side reactions. In the transition-metal-assisted formation of 1,2-dinitrosoalkanes, it was found that the activation barriers for the one-step [3+2] addition pathway for the formation 1,2-dinitrosoalkanes are generally very low while the activation barriers for the [2+2] addition of the C=C bond of the olefins across the M-N bonds of CpM(NO)2 (M=Co, Rh, Ir) to form an intermediate are generally very high. A transition state for the re-arrangement of the products of [2+2] addition to the products of [3+2] addition could not be located, indicating that the re-arrangement of the products of [2+2] addition by reductive elimination involving the second metal-nitrogen π-bond to form the observed 1,2-dintrosoalkanes as suggested in the work of Rappé and Upton may not be possible. Therefore it is concluded that the direct one-step [3+2] addition pathway proposed by Bergman and Becker for the formation of 1,2-dinitrosoalkanes is a more plausible pathway.
- ItemControl of pregnancy-associated malaria through community involvement in rural Ghana(2009-6) Bam, Victoria BubunyoMissing Page
- ItemThree essays on economic impact assessment of the use of the Heavily Indebted Poor Countries (HIPC) initiative for poverty reduction in Ghana(2010) Osei-Fosu, Anthony KofiGhana applied to join the Heavily Indebted Poor Countries (HIPC) in 2001. The argument was that HIPC spending will help to develop capacity of the poor (through human development), give them capital for investment (through micro-credit), improve their labour productivity (through improvement in health and rural water and sanitation), enhance rural agriculture (through feeder roads construction and rehabilitation), give them skill training, etc. These will enhance the incomes of the poor in the immediate future and help them come out of the vicious cycle of poverty. After eight year of implementation there was the need to assess the impact of the initiative on poverty reduction. This study therefore investigates the economic impact of the utilization of the HIPC relief fund on poverty reduction in Ghana. Specifically, the study objected to: assess the extent to which the HIPC relief fund has helped to reduce poverty, both at the individual and community levels; determine the relative effectiveness of the various HIPC funded programmes to the reduction of poverty; assess the impact of the HIPC micro-credit on poverty reduction and its benefit incidence; examine how the poor themselves feel about how the programmes have improved their welfare and hence reduced their poverty situation; and examine the extent to which the HIPC initiative has improved the asset, need-base and capabilities of the poor that will make them function as economic and social being. These research concerns were addressed in the thesis in a three separate but related essays on; Economic Impact Assessment of the Heavily Indebted Poor Countries (HIPC) Initiative on Poverty Reduction in Ghana; The Heavily Indebted Poor Countries (HIPC) Initiative Micro-credit and Poverty Reduction in Ghana: a Panacea or a Mirage?; and Assessment of the Impact of the Heavily Indebted Poor Countries (HIPC) Initiative on Poverty Reduction: The Subjective-Multidimensional and Deprivation Approach, in that order. The techniques that were used for the analysis included: FGT Index method (Foster, Greer and Thorbecke, 1984); Community Poverty Ratio method (Sullivan, 2002); Benefit Incidence Analysis methods (Demery, 2003); Subjective-Multidimensional Model (Van Praag et al, 1982); Multidimensional Deprivation method (Barrientos, 2003); Capabilities and Functioning model (Sen, 1983), among others. The definitions and details of these approaches are provided in the appropriate essays that constitute the Thesis. The study used method with no counterfactual (before and after), which compares the performance of key variables after the initiative with those prior to the initiative. The approach uses statistical methods to evaluate whether there is a significant change in some essential variables over the period. The study uses both primary and secondary data. The primary data were derived from household survey. Some of the major findings of the study are summarised as follows: In the first essay, the study found that over the period when the Heavily Indebted Poor Countries (HIPC) initiative was implemented per capita income of the households have significantly increased and therefore decreasing the proportion of the people below the poverty line. The Foster-Greer-Thorbecke (FGT) Poverty Gap Index (PGI) also indicates that the proportion of income needed to transfer the poor above the poverty line has also significantly reduced over the period. By implication over the period poverty incidence has been reduced. Secondly, the extent of community deprivation of social amenities reduced. That is over the period of the HIPC implementation (2001-2008) more social amenities were provided to the communities. For example 27 more communities were provided with health facilities, 30 were connected with electricity, 40 got access to telephone facilities and 33 communities had their feeder roads re-shape to all weather roads. It also came out that there was improvement in human development outcomes; school enrolment, attendance, retention, completion rate, school performance, adult literacy rate, life expectancy at birth, coverage of vaccination, and delivery assistance increased over the period while infant mortality, maternal mortality, malnutrition, malaria rate, cholera cases, and guinea worm cases went down. Furthermore, the study found that the improvement in the human development outcomes significantly relate to HIPC initiative funds, except in the case of school performance, adult literacy rate and malaria cases. Hence, it can be said that with respect to the provision of social amenities for communities the HIPC initiative has done marvelously well to reduce poverty in Ghana. Thirdly, the ordinary least square (OLS) analysis proved significantly that the poverty reduction is positively related to the initiative. Hence, the hypothesis that the HIPC initiative has reduced poverty in Ghana is accepted and therefore the strategies used under the initiative have high potential to Ghana’s future poverty reduction, growth and over-all economic development. Furthermore, the study found that the most effective programme to poverty reduction is education, followed by health and water and sanitation. These programmes proved statistically significant relationship to the poverty reduction over the period. This means that when funds are shifted from micro-credit, private sector development and good governance, the rate of poverty will fall. The study however found that over the period the intensity of poverty (inequality among the poor) increased implying that the HIPC initiative appears not pro-poorest. This was shown by the increase in the Foster-Greer-Thorbecke (FGT) squared poverty gap index from 2000 to 2008. This means the proportion of income needed to move the more poor to catch up with the less poor has increased over the period. This implies that the initiative was more regressive to the poorer and hence not pro-poor. This suggests that even though the initiative has helped to reduce poverty, it impacted significantly on the less poor in the country than the poorest. Again, some of the programmes; example, the micro-credit, private sector development and good governance appear not to impact on the poor meaning they were probably poorly implemented or they might have long term effects on poverty reduction whose impact cannot be immediately felt. From the second essay, the study found that the HIPC micro-credit is a panacea to poverty reduction in Ghana. That is it has the potential for poverty reduction because between the HIPC implementation period (2001- 2008), the beneficiaries of the HIPC micro-credit had significant increases in their incomes than the non-beneficiaries. However, from the benefit incidence analysis in section 4.5.2 the distribution of the HIPC micro-credit was skewed. Both the standard and the marginal benefits of the micro-credit were distributed regressively towards the rural areas and the poorest income-quintile of the population. This therefore explains why the intensity of poverty (inequality among the poor) increased as discussed in section 3.4.1. By implication, if efforts are made to channel the HIPC micro-credit to the rural areas and the poorest income-quintile of the population, the country is likely to reduce poverty drastically, if not completely eradicate it. The third essay revealed that both the head count and poverty gap indices from Foster-Greer-Thorbecke (FGT) were very high. Also, over the period there was no significant reduction. From counts of domain satisfaction on average over 60% of the households felt that they were poor by all the welfare indicators and therefore it is clear that from the subjective point of view that the initiative did not significantly reduce the poverty situation of the populace. Furthermore, the study found that the initiative did not significantly improve the households’ basic-needs, asset-needs and capabilities that will enable them enhance their well-being and help them to function as economic and social beings. There was no significant statistical difference between the conditions of the households’ basic-needs, asset-needs and capabilities in 2000 and 2008. The study therefore concludes that with respect to basic-needs, asset-needs and capabilities the initiative did not positively impact on poverty reduction over the implementation period.
- ItemFramework Development for Integrating Information and Communication Technologies Into The Ghanaian Senior High School Visual Art Curriculum(2010-07-15) Degraft-Yankson, PatriqueWithin the past decade, efforts at integrating ICT into the school curriculum have become popular in the country's educational institutions. Even before the government of Ghana, on the basis of the Anamuah-Mensah committee on education, recommended ICT infusion into the educational system, there were far-flung ICT integration attempts initiated by Parent/Teacher Associations, Old Students Associations, non-governmental organizations and some ICT related establishments. This indeed is a clear manifestation of how conscious Ghanaians have become about the importance of ICT in institutions of learning. Unfortunately, however, a close observation of the emergence of ICTs in Ghanaian Senior High Schools seems to lack definite goals for teaching and learning. Besides, attempts at ICT integration are happening so independently that the extent to which its infusion or introduction (to phrase itrealistically) is benefiting education of the students is uncertain. It is for this reason that a Curriculum Framework aimed at developing the use of ICTs in the teaching and learning of Visual Arts in Ghanaian senior high schools is considered essential. This study begins with an examination of the opinions and knowledge base of Art teachers and students about ICT and Art Education. It also explores the educational goals of existing ICT progarmmes in Ghanaian Senior High Schools which focus on conventional computing that only enables students to use a narrow range of software that have very little benefit for the Visual Art student in particular. The study further seeks the views of ICT experts, curriculum planners/reviewers, teachers and other stake holders concerning effective integration of ICT into the teaching and learning of visual arts in the senior high schools. Two key dimensions emerged from the views sampled from Visual Art teachers, students, curriculum reviewers and ICT experts: (1) Motivation for ICT integration and usage, based on (2) Curricular and pedagogical innovations. Despite the divergence in opinions, beliefs and attitudes, Visual Art teachers and students seem ready and highly motivated by the promises of new technologies to use ICTs. However, this can be possible only when efforts are formally put in place to ensure innovations in pedagogy through a qualitative change in the existing Visual Art curriculum. The outcome of the investigations formed the rationale for developing a Framework for Integrating ICTs into the Ghanaian Senior High Schools Visual Art Curriculum. The framework aims at exposing students in the Visual Arts to relevant basic skills that are required to develop their computer literacy skills beyond word processing, ultimately developing their creative thinking skills through information and communication technology.
- 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.
- ItemModelling Customers Response to Service offers using game Theory Case Study; MTN and Vodafone in Bolgatanga Polytechnic(2011-11-18) Issahaku, Abdul-MajeedGame theory is being found to be one of the useful tools for analysing strategic situations that involve competitors or rivals who struggle against each other for supremacy...
- ItemAn In Vitro Model of Endemic Burkitt’s Lymphoma (eBL) Pathogenesis; Cooperation of Plasmodium Falciparum and Epstein Barr Virus in DNA Damage Mediated Via Activation Induced Cytidine Deaminase.(2012-06-15) Ayivor-Djanie, ReubenPlasmodium falciparum (P. falciparum) and Epstein-Barr virus (EBV) infections are contributors in the pathogenesis of endemic Burkitt’s lymphoma (eBL), although the precise mechanism of their synergy remains elusive. Reports suggest that the role of P. falciparum is indirect, creating a permissive environment for the outgrowth of EBV. EBV on the other hand invades and immortalizes lymphocytes in vitro and upregulates activation-induced cytidine deaminase (AID), a DNA repair enzyme responsible for diversifying the antibody repertoire and a potent mutagen capable of inducing the genetic damage characteristic of eBL. It is yet to be shown how exposure to P. falciparum affects the expression of AID in lymphocytes. The aim of this work was to investigate the possible direct role of P. falciparum in eBL lymphomagenesis by exploring parasite-lymphocyte interactions and AID expression after exposure to P. falciparum and/or EBV. Malaria positive slides were examined for parasite-lymphocyte interactions and primary tonsillar mononuclear cells (MNCs) were co-cultured with RBCs infected with up to 5% parasitemia of the 3D7 strain of P. falciparum. Geimsa stained thin smears were made from these co-cultures and examined for parasite-MNC interactions over a five day period. No direct parasite-MNC interaction was observed from all slides examined. The levels of AID mRNA in MNCs was measured by qPCR after in vitro exposure to P. falciparum and/or EBV, and in the presence or absence of 2µg/ml cyclosporine. P. falciparum induced up to a 6-fold increase in AID over unstimulated controls, EBV induced a 13-fold maximum increase, and both pathogens together induced up to a 22-fold increase in AID. With cyclosporine, AID mRNA levels in the P. falciparum stimulated cultures remained unchanged. EBV alone induced a 22- fold increase in AID and both pathogens together induced a 42-fold increase in AID. DNA damage was estimated by Comet Assay and quantified with an algorithm from the Comet Assay Project Lab (CASP). DNA comets revealed that P. falciparum induced moderate DNA damage in MNCs with up to 5.6% and 10% DNA in tails of comets with and without cyclosporine respectively. Cultures stimulated with EBV recorded DNA damage of up to 16% and 13% DNA in tails of comets with and without cyclosporine respectively; and both pathogens induced DNA damage with up to 11% and 16% DNA in tails of comets with and without cyclosporine respectively. The levels of DNA damage in these cells correlated with AID levels and demonstrate that P. falciparum plays a direct role in eBL pathogenesis, by inducing AID expression to levels similar to that expressed in BL cells and cooperating with EBV to induce abnormally high levels of AID and DNA damage.
- ItemThe kinetics of mycolactone in relation to the microbiological, clinical and immunological responses to antibiotic therapy for mycobacterium ulcerans disease.(2014) Sarfo, Fred StephenBackground: Mycobacterium ulcerans is the causative agent for a chronic necrotising skin infection called Buruli ulcer. Pathology of the disease is closely linked with the elaboration of a unique lipid toxin, mycolactone, which has potent cytotoxic and immunomodulatory properties. In this study, assays were developed to detect and quantify mycolactone concentrations in tissues during curative antibiotic therapy in mice and in humans to understand its dynamics in pathogenesis and to explore its potential as a biomarker for diagnosis and monitoring of patients with Buruli ulcer disease on antibiotic therapy. The currently recommended antibiotic regimen for the management of Buruli ulcer is a combination of daily intramuscular injections of streptomycin and oral rifampicin for 8 weeks (RS8). This regimen was compared with streptomycin/rifampicin for 2 weeks followed by clarithromycin/rifampicin (RS2RC6) for 6 weeks in patients to determine the clinical and bacteriological effectiveness in a pilot study. Methods: Biopsies were obtained from infected human skin tissues and BALB/c mouse hind footpads before, during and after 8-weeks of rifampicin-containing combination antibiotic therapy. Lipids were extracted from tissues using organic solvents, mycolactone concentrations were measured using a cytotoxicity assay and mass spectrometry. Trends in mycolactone concentrations and clinical, bacteriological and immuno-histopathological responses were determined. Concentrations of cytokines in supernates of whole blood assays in humans or murine splenocytes after stimulation with mycobacterial antigens/T-cell mitogens were measured using ELISA. iv Results: Eighty-three patients with confirmed Buruli ulcer were randomized to RS8 or RS2RC6 and monitored for recurrence free-healing. Bacterial load in tissue samples before and after treatment for 6 and 12 weeks was monitored in samples obtained by 4mm punch biopsy by semi-quantitative culture. There was no difference in using RS8 or RS2RC6 with respect to healing rate or the proportion healed in each group after 4, 8, 12, 16, 20, 24 and up to 52 weeks. The success rate was 93% in each group and there was no recurrence after 12-month follow-up. There was no difference in the number of bacteria cultured at the different time points for the two regimens. Mycolactone was detectable in 92% and 77% of human samples (n=80) using cytotoxicity assays and mass spectrometry respectively. Antibiotic therapy was associated with a decline in tissue concentration of mycolactone in both human and murine-infected tissues which was paralleled by resolution of clinical lesions, reductions in bacteriological counts and restoration of local and systemic immune responses. Discussions/Conclusions: This study shows that mycolactone concentrations in tissues is closely associated with the presence of M. ulcerans and provides useful proof-of-concept data that mycolactone detection could potentially be used to monitor response to antibiotic therapy as well as for diagnosis of Buruli ulcer disease. The findings from the pilot study indicate that rifampicin combined with clarithromycin can replace rifampicin and streptomycin for the continuation phase after rifampicin-streptomycin treatment for 2 weeks without any apparent loss of efficacy. The implication is that a controlled trial of fully oral therapy using rifampicin and clarithromycin for 8 weeks (RC8) is justified.
- 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 kinetics of mycolactone in relation to the microbiological, clinical and immunological responses to antibiotic therapy for mycobacterium ulcerans disease.(2014-11-20) Sarfo, Fred StephenBackground: Mycobacterium ulcerans is the causative agent for a chronic necrotising skin infection called Buruli ulcer. Pathology of the disease is closely linked with the elaboration of a unique lipid toxin, mycolactone, which has potent cytotoxic and immunomodulatory properties. In this study, assays were developed to detect and quantify mycolactone concentrations in tissues during curative antibiotic therapy in mice and in humans to understand its dynamics in pathogenesis and to explore its potential as a biomarker for diagnosis and monitoring of patients with Buruli ulcer disease on antibiotic therapy. The currently recommended antibiotic regimen for the management of Buruli ulcer is a combination of daily intramuscular injections of streptomycin and oral rifampicin for 8 weeks (RS8). This regimen was compared with streptomycin/rifampicin for 2 weeks followed by clarithromycin/rifampicin (RS2RC6) for 6 weeks in patients to determine the clinical and bacteriological effectiveness in a pilot study. Methods: Biopsies were obtained from infected human skin tissues and BALB/c mouse hind footpads before, during and after 8-weeks of rifampicin-containing combination antibiotic therapy. Lipids were extracted from tissues using organic solvents, mycolactone concentrations were measured using a cytotoxicity assay and mass spectrometry. Trends in mycolactone concentrations and clinical, bacteriological and immuno-histopathological responses were determined. Concentrations of cytokines in supernates of whole blood assays in humans or murine splenocytes after stimulation with mycobacterial antigens/T-cell mitogens were measured using ELISA. iv Results: Eighty-three patients with confirmed Buruli ulcer were randomized to RS8 or RS2RC6 and monitored for recurrence free-healing. Bacterial load in tissue samples before and after treatment for 6 and 12 weeks was monitored in samples obtained by 4mm punch biopsy by semi-quantitative culture. There was no difference in using RS8 or RS2RC6 with respect to healing rate or the proportion healed in each group after 4, 8, 12, 16, 20, 24 and up to 52 weeks. The success rate was 93% in each group and there was no recurrence after 12-month follow-up. There was no difference in the number of bacteria cultured at the different time points for the two regimens. Mycolactone was detectable in 92% and 77% of human samples (n=80) using cytotoxicity assays and mass spectrometry respectively. Antibiotic therapy was associated with a decline in tissue concentration of mycolactone in both human and murine-infected tissues which was paralleled by resolution of clinical lesions, reductions in bacteriological counts and restoration of local and systemic immune responses. Discussions/Conclusions: This study shows that mycolactone concentrations in tissues is closely associated with the presence of M. ulcerans and provides useful proof-of-concept data that mycolactone detection could potentially be used to monitor response to antibiotic therapy as well as for diagnosis of Buruli ulcer disease. The findings from the pilot study indicate that rifampicin combined with clarithromycin can replace rifampicin and streptomycin for the continuation phase after rifampicin-streptomycin treatment for 2 weeks without any apparent loss of efficacy. The implication is that a controlled trial of fully oral therapy using rifampicin and clarithromycin for 8 weeks (RC8) is justified.
- 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.
- ItemThermophysical Properties of Selected Cash Crops Grown in Ghana(2015-05-22) Bart-Plange, Prof AtoIn this thesis, the influence of moisture on selected physical, compressive and thermal properties of cocoa beans, shea and cashew nut and kernel were studied. Standard methodologies that have been accepted internationally and used by several researchers globally were used for the determination of the selected properties in moisture content ranges normally used for the postharvest processing of the selected crops. The results of moisture variation on physical properties of cocoa beans and cashew kernels such as 1000-bean mass, true density, porosity, emptying angle of repose and static coefficient of friction showed increasing trends with linear relationships while bulk density decreased linearly for cocoa bean and cashew kernel samples. The compressive strain and Young’s Modulus for cocoa beans decreased linearly with moisture from 0.009 to 0.0045, and 1300 to 205 MPa respectively. However the compressive stress decreased exponentially with increasing moisture content from 1.5 - 0.3 MPa while the crushing energy had more positive linear function with moisture content and increased from 0.013 - 0.2 J. For shea kernel, compressive stress, compressive strain and Young’s Modulus decreased linearly from 2.0 - 0.8 MPa, 0.0085 - 0.002 mm/mm and 2000 – 100 MPa with increasing moisture content. Crushing energy increased non-linearly from 0.005 - 0.13 mJ in the moisture content range of 5% - 24% w.b. The compressive stress, strain, and Young’s modulus for the cashew kernel increased from 0.214 - 1.214 MPa, 0.355 - 0.472 mm/mm, and 2.446 - 6.416 MPa respectively as moisture content increased from 5.0 - 9.0% wb. Thermal conductivity increased linearly for ground cocoa beans sample from 0.0243 - 0.0311 W/oCm and for ground shea kernels from 0.0165 - 0.0458 W/oCm in the moisture content range of 12.59 - 43.84%w.b. at a constant bulk density of 295 kg/m3. Specific heat, thermal conductivity and thermal diffusivity for ground cashew kernel were found to increase linearly from 1586 – 1756 J/kgº., 0.2103 - 0.2296 W/mK and 2.369×10-7 - 2.588×10-7 m2/s with increasing moisture content from 5.0 - 9.0% w.b. Keywords: Cocoa beans, shea kernel, cashew kernel, physical properties, compressive properties, thermal properties, moisture content. iii Contribution to Science and Technology From this study, the following have been established and therefore added onto the scientific knowledge on engineering properties of food materials: 1. The publication on the physical properties of cocoa beans has been cited by 96 related articles as found in google thus contributing to information on physical properties of food grains. 2. The findings on crushing energy provide useful information for food and agricultural engineers in the design of suitable cocoa beans, shea and cashew nut crackers. 3. In a bid to mechanize the various unit operations involved in the postharvest processing of shea and cashew kernel, information and data on the behaviour of these strength properties as a function of moisture is needed. These data when utilised fully will not only save energy but will promote the design and development of effective and efficient processing machines. 4. Attempts have been made to optimize the drying process and to minimize internal cracking during drying of food grains with the aid of mathematical and numerical drying models, but estimation of the thermal properties of the material being dried, is also required. Data generated on specific heat, thermal conductivity, thermal diffusivity could be used in the analysis of drying processes and storage conditions. iv Publications from Candidate’s Work 1. Bart-Plange, A., Dzisi, K. A., Addo, A., Teye, E. and Kumi, F. (2012). A comparative study of some physical properties of large and medium size Cocoa beans from Ghana. ARPN Journal of Science and Technology. 2(3): 135-141, March.www.ejournalofscience.org. ISSN NO.: 2225-7217. 2. Bart-Plange, A. P. Mohammed-Kamil, A. Addo and E. Teye (2012). Some Physical and Mechanical Properties of Cashew Nut and Kernel Grown in Ghana. International Journal of Science and Nature (IJSN). 3(2): 406-415, May 2012.www.scienceandnature.org. ISSN NO.: 2229-6441. 3. Bart-Plange, A., Addo, A., Abano, E.E. and Akowuah, J.O. (2012). Compressive Properties of Cocoa Beans Considering the Effect of Moisture Content Variations. International Journal of Engineering and Technology (IJET UK). 2(5): 850-858 http:/www.iet-journals.org. ISSN NO.: 2049-3444. 4. Bart-Plange, A. Addo, J. O. Akowuah and J. Ampah (2012). Some moisture dependent compressive properties of Shea Kernel (vitellaria Paradoxa L). Canadian Journal of Pure and Applied Sciences (CJPAS), 6(3): 2113-2119, www.cjpas.net. ISSN NO.: 1920-3853. 5. Bart-Plange, A. Addo, F. Kumi, and A. K. Piegu (2012). Some moisture dependent thermal properties of Cashew kernel (Anarcardium occidentale L.). Australian Journal of Agricultural Engineering. AJAE 3(2): 65-69. ISSN NO.: 1836-9448. 6. Bart-Plange, A. Addo, S. K. Amponsah and J. Ampah (2012). Effect of Moisture, Bulk Density and Temperature on Thermal Conductivity of Ground Cocoa Beans and Ground Sheanut Kernels. Global Journal of Science Frontier Research (GJSFR). 12( 8). ISSN NO.: 2249-4626.
- 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.
- ItemLong -Term Vegetation Dynamics over the Bani River Basin as Impacted by Climate Change and Land Use(2015-07-29) Traore, Souleymane SidiThis study investigated the long-term trends in vegetation and rainfall and the extent and rate of vegetation change over the Bani river Basin at multiple spatial and temporal scales in relation to local and regional drivers. Monthly 8-km Normalized Difference Vegetation Index (NDVI) time-series data from 1982 to 2011 was derived from 10-day Satellite Pour l’Observation de la Terre vegetation product (SPOT-VGT) at 1-km (1998-2011) and 15-day GIMMS (Global Inventories Monitoring and Modelling Systems) at 8-km satellite data (1982-2006). Gridded rainfall data at 8-km grid resolution was created from 40 meteorological stations and complemented with Tropical Rainfall Measurement Mission (TRMM) data. A Mann Kendall (MK) trend analysis was used to determine the trend for each dataset using monthly and annual time-series. This analysis produced some indicators like Kendall’s tau, p-value and Theil-Sen. The p-value estimator (p-value less than 0.07) was used in this study to show the significance of the trend. Trend analysis revealed that within the study area vegetation greening trends are mostly associated with areas where natural vegetation is still well represented. From the results 934 pixels (49% of the study area) showed a positive trend while 155 pixels (8% of the study area) showed a negative trend significant at p-value less than 0.07. During the same period rainfall had increased by about 17 mm, translating into a positive trend for almost the entire study area. Vegetation productivity in the study area is dependent on rainfall which varies greatly temporally and spatially. The linear Pearson correlation was used to estimate the relationship between NDVI and rainfall for every pixel at monthly interval for the growing season data. Comparing their long-term mean the result showed a good correlation between the two datasets with an R value of 0.98. Four (4) reference areas were used to explain and cross verify representative areas that exhibit either entirely negative MK-trends or entirely positive MK-trends over the monitoring period. These reference areas were selected based on their trend in rainfall and NDVI and their NDVI long-term departure. Free 30-meter Landsat images were acquired for the four reference areas for the following three intervals: 1984 and 1986, 1999 and 2000 and 2009 and 2010. Land Use/Land Cover (LULC) change was then quantified and the rate of land conversion was determined. LULC variables included urban, Cropland and natural vegetation (Shrublands, Steppe, Open Trees and Closed Trees). For the entire period, the class ‘Natural Vegetation’ decreased between 22.83% and 63.47% from its initial area for areas (1) and (2), while the decrease was 8.35% for area (3) and 13.39% for area (4). The class ‘Cropland’ increased for 564.86% in area (3); 62.17% in area (4); 35.79% in area (2) and 16.22% in area (1). To investigate whether there is a relationship between NDVI, rainfall and LULC change, LULC variables were correlated with long-term trend in rainfall and NDVI. The results showed there is a positive correlation between increases in rainfall and some land cover classes, while some classes such as settlements were negatively correlated with vegetation productivity trends. Croplands and Natural Vegetation were positively correlated (r=0.89) with rainfall while settlements have a negative correlation with NDVI time series trends (r=-0.57). Despite the fact that rainfall is the major determinant of vegetation cover dynamics in the study area, it appears that other human-induced factors such as urbanisation have negatively influenced the change in vegetation cover. The results provide spatially explicit and temporally good and rich information of vegetation productivity dynamics and its drivers at landscape scale. This is an important input for assessing the impact of climate change on vegetation for biophysical modelling. It also improves our knowledge of the drivers of vegetation productivity changes. The study suggests that NDVI can be useful for general vegetation cover monitoring and planning. Future studies need to also look at the effect of vegetation cover change in regard to other landscape components such as specifically population density and soil degradation.
- ItemEvaluating the role of the Ghanaian pharmacist in medication safety strategies in hospitals(2015-11-04) Acheampong, FranklineHealthcare has always been a risky venture with a lot of harm associated with it. Medicines form a major and vital part of the healthcare delivery system. The World Health Organisation and many national safety organisations have created a lot of awareness about the importance of enhancing patient safety in the healthcare system. Evidence available suggests that a lot of adverse drug events especially medication administration errors occur during the medication use process. Consequently, it is important to detect and prevent errors at the drug administration stage, since it is also the last step before these errors could reach patients. In Ghana, little is known of the prevalence and contributory factors of medication administration errors. Current literature suggests the existence of many medication safety strategies that are being employed. Pharmacists in particular, have been identified to contribute immensely to the safe use of medicines globally. The aim of this study was to determine the existence of adverse drug events with emphasis on medication administration errors, explore the perceived roles and documented evidences of pharmacists’ roles in the safe use of medicines and understand the experiences and expectations of doctors and nurses on such roles. Methods The methods used were the following: • A direct non-participatory observation of medication administration by nurses followed by face-to-face interview with a sample of these nurses at the Surgical Medical Emergency Department of Korle Bu Teaching Hospital. • Survey of pharmacists working in Ghanaian hospitals across the country using a structured questionnaire. • Retrospective evaluation of documented clinical intervention reports followed by key informant interviews of pharmacists involved in the reporting. • Open and close-ended questionnaires administered to a conveniently sampled doctors and nurses at the hospital to explore their perceptions and expectations. Key findings • Medication administration errors occurred at a rate of 27.2% at the emergency setting. It was also shown that most of the causes of the errors were related to staff and environmental factors such as workload, and lack of adequate knowledge about medication and their use. • Pharmacists in Ghanaian hospitals perceived their services to be useful in preventing adverse drug events. They indicated that they spent more time on activities with perceived greatest impact on patient care such as reviewing pharmacotherapies, monitoring adverse drug reactions and counselling patients on medication use. • Documented evidence of Pharmacist’s clinical interventions activities revealed that 24 pharmacists made 1019 clinical interventions in 448 handwritten reports. Majority (76.1%) of the interventions related to drug therapy changes. The pharmacists reported that the major barrier to their medication safety roles was the perceived discrepant attitude of doctors and nurses. • In contrast, doctors and nurses indicated that they interacted frequently with pharmacists and acknowledged their roles to be useful in contributing to medication safety. Conclusions and Recommendations • Medication administration errors were observed in over a quarter of the activities of the nurses involved in the study. • There was an overwhelming evidence of the strategic role of hospital pharmacists in identifying and preventing adverse drug events. • Unlike the perception that pharmacists had about the discrepant attitudes of doctors and nurses, the clinicians acknowledged and appreciated the role of the pharmacist in medication safety. • The clinical role of pharmacist in hospitals should be intensified to enhance safety and patient care.
- ItemPreparation and characterization of fat particles-in-water emulsions for the encapsulation of bioactive compounds using allanblackia seed fat and tween 20 and sodium alginate as emulsifying agents(2015-11-09) Badu, MercyEffective delivery of poorly water-soluble bioactive ingredients has been considered a great challenge in the pharmaceutical, food and cosmetic industries. The compartmentalized hydrophobic and hydrophilic regions of emulsion systems give them the advantage to encapsulate polar and non-polar compounds for effective delivery. However, the challenge associated with emulsions is their thermodynamic instability. This study investigated the stabilisation process of fully crystallised fat globules as a dispersed phase in an oil-in-water emulsion system prepared from a naturally occurring vegetable fat, a nonionic surfactant and a polysaccharide biopolymer. The crystallisation profiles of the fats from Allanblackia seed and shea nuts were determined. Based on the results Allanblackia seed fat was selected and used as the dispersed phase in the oil-in-water emulsion system. The emulsion was formulated in the presence of Tween 20 and sodium alginate. The mixed emulsifier system gave stability against aggregation of the fat particles hence preventing coalescing, creaming and flocculation and this was more significant at 2 % to 4 % sodium alginate content. The emulsion particle size and microstructure were dependent on the fat/water ratio and a viscoelastic system with G′ > G′′ at the lower frequencies and G′′ > G′ at higher frequencies (where G and G are….). The dispersed fat particles emulsion system was used to encapsulate sudan orange dye (a water insoluble dye) and the efficiency of the encapsulation was characterized by an increase in particle size (ranging from 246 to 250 nm) and varying size distribution. UV-Vis spectrophotometric analysis of the dye loading capacity, release rate and leaching capacity showed a successful entrapment of the dye in the fat matrix. This confirms Allanblackia seed fat as a potential solid fat for its application in the formulation of oil-in-water emulsions.
- ItemMechanistic Studies and Mathematical Models for Mycolactone Toxin and Autoinhibitory WASP: Model Mechanisms for Buruli ulcer Initiation and Spread.(2015-11-09) Nyarko, Peter RomeoThe Wiskott-Aldrich Syndrome Protein (WASP) has been implicated in many diseases such as Wiskott-Aldrich Syndrome (WAS) and Buruli ulcer. Mycobactrium ulcerans is the main causative organism of Buruli ulcer (BU) disease. The bacteria secretes a polyketide lipid toxin (Mycolactone). The toxin not only di uses through the cell membranes, but also binds, hijacks and disrupts the normal functions of WASP in the cytoplasm leading to over polymerization of actin lament, cytoskeletal rearrangement and eventually cell death through necrosis. In pre-ulcerative BU disease, toxins extend beyond the actual size of the lesion. A mathematical model is developed to describe the binding mechanism of the two conformations of WASP and the complexes formed using the idea of isomerization. The formulation utilizes ligand concentration-dependence (ligand-receptor), equilibrium and conservation principles. By this approach, we are able to determine the fractional response of WASP against change in concentration of its activators;
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