College of Basic and Applied Sciences

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    Comparative Study of Phosgene Gas Sensing Using Carbon and Boron Nitride Nanomaterials-A DFT Approach
    (Molecules, 2021) Kweitsu, E.O.; Dodoo-Arhin, D.; Armoo, S.K.; et al.
    Phosgene (COCl2 ), a valuable industrial compound, may be a public safety and health risk due to potential abuse and possible accidental spillage. Conventional techniques suffer from issues related to procedural complexity and sensitivity. Therefore, there is a need for the development of simple and highly sensitive techniques that overcome these challenges. Recent advances in nanomaterials science offer the opportunity for the development of such techniques by exploiting the unique properties of these nanostructures. In this study, we investigated the potential of six types of nanomaterials: three carbon-based ([5,0] CNT, C60, C70) and three boron nitride-based (BNNT, BN60, BN70) for the detection of COCl2 . The local density approximation (LDA) approach of the density functional theory (DFT) was used to estimate the adsorption characteristics and conductivities of these materials. The results show that the COCl2 molecule adsorbed spontaneously on the Fullerene or nanocages and endothermically on the pristine zigzag nanotubes. Using the magnitude of the bandgap modulation, the order of suitability of the different nanomaterials was established as follows: PBN60 (0.19%) < PC70 (1.39%) < PC60 (1.77%) < PBNNT (27.64%) < PCNT (65.29%) < PBN70 (134.12%). Since the desired criterion for the design of an electronic device is increased conductivity after adsorption due to the resulting low power consumption, PC60 was found to be most suitable because of its power consumption as it had the largest decrease of 1.77% of the bandgap.
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    Surface Functionalized MXenes for Wastewater Treatment-A Comprehensive Review
    (Global Challenges, 2022) Damptey, L.; Dodoo-Arhin, D.; Jaato, B.N.; et al.
    Over 80% of wastewater worldwide is released into the environment without proper treatment. Whilst environmental pollution continues to intensify due to the increase in the number of polluting industries, conventional techniques employed to clean the environment are poorly effective and expensive. MXenes are a new class of 2D materials that have received a lot of attention for an extensive range of applications due to their tuneable interlayer spacing and tailorable surface chemistry. Several MXene-based nanomaterials with remarkable properties have been proposed, synthesized, and used in environmental remediation applications. This work, a comprehensive review of the state-of-the-art research progress on the promising potential of surface-functionalized MXenes as photocatalysts, adsorbents, and membranes for wastewater treatment are presented. The sources, composition, and effects of wastewater on human health and the environment are displayed. Furthermore, the synthesis, surface functionalization, and characterization techniques of merit used in the study of MXenes are discussed, detailing the effects of a range of factors (e.g., PH, temperature, precursor, etc.) on the synthesis, surface functionalization, and performance of the resulting MXenes. Finally, the limits of MXenes and MXene-based materials as well as their potential future research directions, especially for wastewater treatment applications are highlighted.
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    Consumer Preference Heterogeneity and Preference Segmentation: The Case of Ecolabeled Salmon in Danish Retail Sales
    (Marine Resource Economics, 2020) Ankamah-Yeboah, I.; Asche, F.; Bronnmann, J.; et al.
    The popularity of sustainably produced food products has grown rapidly in recent years. Ecolabels are used to indicate the environmental sustainability of products and have been implemented in the seafood market, with the leading ecolabel being that of the Marine Stewardship Council (MSC) for wild fish. However, the effect of ecolabels on consumer decision-making remains unclear regarding actual purchasing behavior. This study analyzes scanner data from a household panel in Denmark, accounting for consumer heterogeneity using random parameters and latent class logit models to identify the effect of ecolabels. The results indicate substantial consumer preference heterogeneity concerning important salmon attributes. Salmon attributes that confer convenience to household fish consumption appear to be very important in consumer choices. Ecolabeling has a significant effect on household decision-making, but the majority of consumers are more likely to choose non-labeled products, which may be due to the low availability of eco-labeled products. Five consumer segments are identified, revealing one consumer segment with a preference for organic labeled salmon, comprising 15% of households. However, a consumer segment for MSC-labeled salmon is not identified. The implication is that management can rely on a segment of consumers to implement organic principles in salmon farming, but the preference for sustainable salmon fishing is inconclusive due to uncertain confounding effects.
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    Physicochemical, Functional Properties And Mycotoxin Occurrence Of Ghanaian Tigernuts (Cyperus Esculentus L.)
    (University of Ghana, 2022-06) Battuta-Dawlah
    In Ghana, tigernut (Cyperus esculentus L.) is grossly underutilized in food applications and is mostly consumed raw as a snack. However, the soil and climate conditions of the country are conducive for cultivation of the crop on a large scale for applications in food for local consumption, industrialisation and for the export market. Food applications of tigernut and its derivatives and their possible inclusion as ingredient in the Ghanaian diet would require knowledge on its handling quality and functional properties. The aim of this study was to characterise Ghanaian tigernut as an ingredient for possible food applications. The study design consisted of two parts: (a) a cross-sectional survey of different categories of stakeholders using pre-tested semi-structured questionnaires (b) followed by laboratory designed experiments to study the quality, physicochemical and functional properties of tigernut as a function of tigernut variety and process conditions. For the surveys, a total of 1277 stakeholders in the value chain, comprising of 711 consumers and 487 traders (wholesalers/retailers) in Greater Accra region and 79 tigernut farmers in the Western and Eastern regions of Ghana, were interviewed using semi-structured researcher-administered questionnaires. The questionnaires sought to gain information on respondents’ level of knowledge on mycotoxins, as well as ascertain if measures were in place to mitigate the risk of fungal colonisation of the crop along the supply chain. Additionally, tigernuts collected at various points along the supply chain (farm, wholesale and retail) were analysed for their mycotoxin (aflatoxins and ochratoxin A) levels using reverse phase High-Performance Liquid Chromatography (HPLC), to determine the hot spots of mycotoxin contamination along the value chain. The second part of the study investigated the physical characteristics of tigernut tubers as well as the functional properties of tigernut flour with the aim of determining its suitability in food applications. Additionally, the shelf life of the tigernut flour was determined by accelerated shelf life testing using the Arrhenius model. Fresh tigernut milk is usually University of Ghana http://ugspace.ug.edu.gh iii characterised by the sedimentation of starch which influences its flow behaviour as well as the physical stability. Furthermore, heat treatment of the milk leads to gelatinisation of the starches, which also affects the same properties. Consequently, the effects of heat (by roasting tigernuts) and adding α- amylase to the tigernut milk on the physicochemical and functional properties of tiger nut milk were studied. Tigernut oil was extracted and the phenolic and functional properties were determined as well as the effect of heat on these properties. The macro nutritional composition of tigernut tuber, flour, oil and milk were also investigated. The results of the surveys showed that tigernut farmers and consumers had appreciable knowledge in and displayed better attitude towards the prevention of mycotoxin contamination than the tigernut traders (wholesalers/retailers). The educational level of all stakeholders influenced their attitude and knowledge towards the prevention of mycotoxin contamination. Almost all consumers were willing to try new tigernut products such as the flour, oil and milk and would like to see more of these products on the Ghanaian market. The number of samples and the levels of mycotoxins (Ochratoxin A and aflatoxins) increased as the value chain progressed, with retail samples containing all the mycotoxins analysed. Total mycotoxins ranged from 0-27 µg/kg at the farm stage to 0-52 µg/kg at the wholesale stage and finally to 7.9 to 1115.48 µg/kg at the retail stage. These highlight post-harvest stage of the value chain as the focal point for mycotoxin prevention programs, although mycotoxin prevention can be agreed as a cumulative process. Both black and yellowish-brown tigernut flours contained relatively high and comparable amounts of sucrose, glucose and fructose. The relatively high resistant starch content of the tigernut flour makes the flour ideal for diabetics and weight watchers. The yellowish-brown variety had higher total starch content, higher water-retaining ability and viscosity at heating and holding cycles as compared to the black variety. Titratable acidity was found to be the crucial determinant of spoilage in tigernut flour and higher temperature was observed to increase the oxidation of the tigernut flour. This may imply that tigernut flour should be stored below room temperature. Heat and the addition of α- amylase increased the total solids, brix and titratable acidity but caused a decrease in the pH of the tigernut milk. Addition of 0.2% of α- amylase to roasted tigernut milk improved its emulsion stability. Heat and addition of α- amylase caused the tigernut milk to become darker in colour. The flow behaviour of the tigernut milk exhibited shear thinning (pseudoplastic) fluid properties. This implies that commercial production of milk from tigernut must control parameters such as speed of machines during processing as well as concentrations of food additives such as α-amylase. Chemical qualities such as iodine value, peroxide value, ester value, saponification value, free fatty acids and acid value of oil extracted from tigernut tubers, all increased at higher temperatures whilst antioxidant activity and phenolic content decreased. The functional properties of tigernut oil suggested that the oil is good for frying at lower temperatures and for shorter periods. The carbohydrate component of the tigernut tuber was mainly made up of starch and dietary fibre (resistant starches) which reduced in the milk and oil. Crude fat was the second most abundant component in the tigernut tuber. Quercetin and gallic acid were found in appreciable amounts in the tigernut oil. Although, the protein content in the tigernut milk was lower compared to the tuber, it was probably enough to impart desirable functionality to help stabilize the tigernut milk. Tigernut tuber and its derivatives can offer various options in food products. The safety of the tuber and its products can however be improved when stakeholders of the supply chain are educated and supported to implement strategies that prevent mycotoxin contamination.
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    Assessment of Agricultural Advisory Messages from Farmer-to Farmer in Making a Case for Scaling Up Production: A Qualitative Study
    (The Qualitative Report, 2020) Kwapong, N.A.; Ankrah, D.A.; Boateng-Gyambiby, D.; et.al
    Inadequate access to agricultural extension services often results in poor farm practices, affecting yields and subsequently the income and well-being of smallholder farmers. Given the high demand for agricultural information and the limited capacity of extension services, a farmer-to-farmer extension approach has been explored by many underserved farmers. In this study, we use a qualitative case study approach to explore how cassava farmers who had limited access to agricultural advisory services from public extension agents managed to up-scale their farming business. Our research question was: what lessons can be learned from the lived experience of these farmers to address the current challenges of cassava farming? The results of our study revealed diversity in advisory messages from farmer to farmer and agricultural extension agents. Farmers’ messages focused on encouraging farmers’ commitment and motivation towards farming business, availability of needed financial resources for the entire production season, willingness to reinvest profits, and access to farmland for future expansion. In contrast, the traditional messages from agricultural extension agents focused on encouraging group formation to address marketing challenges, diversification of farm operations, and good agricultural practices. These results show the need for pluralistic extension approaches to ensure farmers get access to necessary information. Keywords: Agricultural Extension, Case Study, Farmer to Farmer Extension, Social Learning
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    Modelling The Relationship Between The West African Mangrove Oyster (Crassostrea Tulipa, L.1819) And The Aquatic And Climatic Environment For Use As A Bio-Indicator In The Densu Estuary
    (University of Ghana, 2021-09) Atindana, S. A.
    Crassostrea tulipa (Lamarck, 1819) in the Densu estuary was investigated from March 2019 to August 2020 for aspects of its ecology; it’s potential as a bio-indicator of environmental variability; and long-term effects of climate variability on shellfish production in Ghana’s artisanal fisheries and its implication on sustainable management of oyster fisheries. Oyster samples were collected monthly and physicochemical parameters namely Temperature (OC), Dissolved Oxygen (mg/L), pH, Total Dissolved Substances (mg/L), Conductivity (µS/cm) and Salinity (0 /00) measured in situ in triplicates. Silicates, Total Alkalinity, Chlorophyll a, microbes (Total Viable Counts, faecal coliform and Escherichia coli) and heavy metals (Lead, Cadmium and Mercury) were measured ex situ following standards of APHA (2015). Relative abundance was measured as Catch Per Unit Effort (CPUE) and growth pattern determined using the TropFishR package in R programming software. The numerical and frequency of occurrence methods were used to determine its food habits. Species-environmental driver relationship was analyzed following Canonical Correspondence Analysis (CCA) approach using the Vegan package (version 2.5-4.) in R studio software (version1.3.1056). CPUE from experimental fishing was significantly (p < 0.05) higher (6-200; 233.33 ± 6.00 kg/hr/fisher/day) than commercial fishing (3-100;78.12 ± 7.11 kg/hr/fisher/day). CPUE was significantly higher (p = 0.0161) at low tide (115-500;50.10 ± 5.3 kg/hr/fisher/day) than high tide (6-200; 62.58 ± 3.12 kg/hr/fisher/day). CPUE was higher (p = 0.023) in the dry season (150.87 ± 1.12 kg/hr/fisher/day) than the rainy season (57.45 ± 0.55 kg/hr/fisher/day). Crassostrea tulipa has a fast growth rate (K= 0.81; L∞ = 13.24 cm). Higher condition index (60 %) was recorded in the rainy season than the dry season (39 %). University of Ghana http://ugspace.ug.edu.gh iv The diet of the oyster was predominated by golden algae (IRI=595), red algae (IRI=209), green algae (IRI=131.37) and diatoms (IRI =172). Densu estuary is a dynamic shallow system with high concentration of total alkalinity and aragonite. Water depth, silicates, e coli and revelle factor were significantly higher (p < 0.05) at high tide than low tide. Also, mean water depth, cadmium, total alkalinity, pH, carbon dioxide, lead, total carbon dioxide, carbon dioxide fugacity and chlorophyll a were significantly higher (p< 0.05) bio accumulated Pb and Cd than big- sized (4.5-5.4g) tissues. Lead, mercury, TVC, faecal coliform and Escherichia coli also bio accumulated in C. tulipa tissues more (BAF > 1) than in the water medium which suggests that it has the ability to provide a measurable response to changes in the estuarine environment. Therefore, C. tulipa in the Densu estuary has the ability to accumulate pollutants from the environment and its morphometric features could give clues on the state of environmental variables. C. tulipa is a good bioindicator for assessing; lead, mercury, Total viable counts, E coli and faecal coliform in the Densu estuary. Densu estuary is high in aragonite and total alkalinity. The predictor variables for; Condition factor is aragonite, shellfish catch is temperature and Shell height & Width are faecal coliform, total carbon dioxide and carbon dioxide fugacity. There is the occurrence of contamination and therefore the need for regular monitoring, enactment of control measures and depuration prior to consumption. Also, the use of refuse dam and sewage outlet should be prohibited. It is recommended that laboratory and field-controlled experiments be conducted on oyster responses to extremes of temperature, aragonite and total alkalinity. There is an urgent need for the collation of data on estuarine/lagoonal shellfisheries in Ghana by Fisheries Commission and other stakeholders on catch trends, gears, effort and income of artisanal oyster collectors.
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    Assessing Individuals’ Littering Behaviour In Public Spaces In The Greater Accra Metropolitan Area
    (University of Ghana, 2021-12) Yandam, R.
    Littering is a social and environmental behaviour involving indiscriminate waste disposal practice that challenges the government's quest for a clean city environment. This study explores individuals' littering behaviour in four urban public spaces in Metropolitan Accra, using cross-sectional convergent parallel mixed methods, including in-depth interviews, focus group discussion, and litter characterisation. The qualitative data analysis employed a thematic approach, while the quantitative data used descriptive statistics and binary logistic regression with IBM-SPSS version 23. Individuals' perceptions revealed that littering is an everyday practice in public spaces resulting from collective action and a strategy to minimise private costs. Norms such as weak law enforcement, lack of litter bin, ineffective informal social controls, and absence of written prompts prohibiting littering were cited as justification for littering. Critical litter abatement approaches recommended included an adequate supply of litter bins, intensifying public education, and strict law enforcement. A binary logistic regression analysis revealed that participant age, group size, gender, activity engagement, litter items, crowdedness, existing litter in the environment, and distance to the litter bin significantly influenced littering behaviour. Also, age and littering behaviour depended on distance and vice versa. The litter characterisation and branded audit recorded 37,280 pieces of items, with two-thirds, i.e., 78% being plastics, while paper recorded 14%, and organic, 2%. Broadly, the water and beverage industry litter, with Kasapreko, Multi Pac Limited, and Special Ice industries were dominant. The study identified factors that drive littering behaviour, including individual and contextual factors such as bad governance and leadership and incompatibility between local cultural norms and policies. The study recommends that the sector Ministry promotes civic responsibilities while urging the manufacturing industry and brand owners to channel corporate social responsibility activities towards post-consumer packaging litter management.
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    Mapping The Kinetics And Diversity Of Adaptive Immune Responses In Children Over The Course Of An Acute Plasmodium Falciparum Infection
    (University Of Ghana, 2021-07) Nyakoe, N.K.
    Naturally acquired immunity to malaria is Plasmodium species strain- and variant- specific. It is non-sterile and short-lived therefore requiring repeated exposure. These protective immune responses are directed against pre-erythrocytic parasites, blood-stage merozoites, or Plasmodium antigens on the surface of infected red blood cells and can be humoral or cellular. The importance of the various immune response components during malaria episodes in exposed populations remains unknown, as conclusive interpretation of data from previous studies has been limited by sampling design, disease definition, patient selection and approaches in natural infections. Long-term malaria protection in humans is likely to be determined by the cumulative effect of multiple low-level immune responses to various antigens, with each person having a unique "protective signature" based on their genetic background. Differences in transmission intensity observed in malaria-endemic areas significantly influence the acquisition of natural immunity to malaria. Antibody and cytokine responses, which contribute to malaria protective immunity, are exposure-dependent; hence, are significantly influenced by transmission intensity. Cytokine levels change rapidly upon exposure to malaria and often dictate the extent of clinical disease, whereas antibodies increase gradually and are long-lasting, and act to control and eliminate parasites. A variety of molecular mechanisms are involved in regulating these immune responses; however, it is still unclear what combination of immune features is essential for protection. Characterization of these host immune responses is important in understanding the bidirectional host-parasite interactions which will aid in effective vaccine development and eventual malaria control and elimination. This study employed a systems immunological approach to profile changes in the cellular, humoral, and molecular components of the immune system during acute P. falciparum infection and after treatment to identify immune signatures associated with varying malaria transmission intensity. Methods: Samples were collected from children of ages 5-14 years in two regions in Ghana with distinct malaria transmission intensities: Accra (low transmission) and Kintampo (high transmission). Whole blood samples were collected and a portion separated to obtain plasma from the participants when they present at the hospital with confirmed P. falciparum infection (Day 0), and convalescent phases (Day 7 and Day 21). Levels of 25 plasma cytokines were determined using a multiplex Luminex human magnetic 25-plex bead array kit. A custom-made protein microarray was used to detect IgG responses to 190 antigenic targets for blood-stage, pre-erythrocytic, and gametocyte stage parasite proteins. Antibodies and cytokine levels from the 2 sites were compared during infection and convalescent phases. Additionally, whole-blood transcriptomes were profiled by RNA-sequencing and differential gene expression compared during infection and convalescent in the study participants. Correlation and machine-learning classifier approaches were used to model immune responses to identify predictive responses correlating with distinct transmission intensities. Gene ontology modules associated with changes in immune responses in the two transmission areas were identified using gene set enrichment analysis. Results: Acute P. falciparum infection was associated with pro-inflammatory cytokines IL-6, IFN-γ, IFN-α, MIG, MCP-1, and IP-10, as well as an immunomodulatory profile mediated by IL-10, IL-2R and IL-1RA. In children from low transmission areas, they were significantly higher than in children in the high transmission areas, whereas, IFN-α, IL-6, IL-1RA, and MCP-1 were significantly associated with parasitemia. In addition, analysis of the correlation network revealed a distinctive signature between individuals from the low and high transmission areas. Of interest, is a subset of children from the high transmission area with detectable parasitemia at day 21 (D21) after treatment, with a unique cytokine signature dominated by IL-10 and IL-1RA. This was associated with asymptomatic parasitemia. Of the 190 Plasmodium antigens tested, 118 had antibody reactivity in more than 80% of the children in our study cohorts. Though overall breadth and magnitude of antibody responses was similar, the composition of these responses was different between individuals from high and low transmission areas. Hierarchical clustering revealed IgG response clusters to antigens associated with different malaria endemicity, with 48/118 antigens including EBA140, ETRAMP5, GLURP, MSP1 and MSP6 associated to low transmission area and 30/118 antigens associated to high transmission area, including Rh5.1, EBA181, VAR2CSA, ACS5, HSP40, MSP2, MSP3, MSP4, and MSP7. Machine-learning and feature selection approaches further predicted 17 antibody signatures (MSP4, MSP2 3D7, MSP1-19 2A, Etramp 5 Ag1 His var 3, MSP1-19 2B, Etramp 5 Ag1 His var 2, MSP2 [15-46b], MSP2 [5-36A], ACS5 Ag 3, PfMSP1_19, MSP3 FVO, Var2CSA, SE36/SERA 5 (T), HSP40 Ag 3, GLURP R2, Rh4.2_2030, and MSP2 CH150/9) that distinguish individuals from these two regions. Multivariable linear regression models predicted age and transmission intensity as factors that highly affect antibody reactivity to most antigens in our panel. Gene expression levels differ with transmission intensity More genes were differentially expressed during infection (D0) compared to convalesces (D7 and D21). Comparison of the DEGs between the two sites show that more genes were highly expressed in low transmission area compared to the high transmission area at D0. In the high transmission area, the DEGs enriched in gene ontology (GO) modules related to B cell and surface signature, T cell development and activation, platelet activation-actin binding, enriched cell cycle, and regulation of transcription and transcription factor modules, were up-regulated. In the low transmission area, there was DEGs in modules associated with cell cycle and transcription, immune activation- generic cluster, E2F1 targets, plasma cell surface signature, immunoglobulins, enriched monocytes, enriched NK cells, platelet activation, enriched neutrophils, enriched activated dendritic cells, NK cell surface signature, chemokine and inflammatory molecules in myeloid cells, Golgi membrane and TBA modules, were up-regulated. Cellular deconvolution revealed an increased proportion of neutrophils cell type in both high and low transmission areas, with decreased CD4 naïve, CD8, B-cells and T-follicular cells, during infection compared to convalescence in both high and low transmission. Our data identified transcription patterns that are distinguish by malaria transmission intensity, where most genes highly expressed in the high transmission area are those involved in adaptive immune response. While genes highly expressed in the low transmission area are those involve in the innate immune response. These data provide insight into molecular and cellular immune response kinetics in natural infection. Conclusion: The findings show that cytokine responses during active malaria infection varies significantly between individuals with differing levels of prior exposure, with individuals from low transmission settings having higher levels of pro-inflammatory cytokines. However, these differences are transient and do not persist during recovery. Whereas antibodies levels remained relatively stable across the timepoints for most antigens in our panel. We show that models trained to capture distinct antibody response patterns predicted 17 antibody responses that are key in distinguishing between individuals from different intensities. Given the important role that exposure plays in the acquisition of immunity these could be useful antigens as possible targets of protective immunity and provides clues for potential vaccine candidates that can be prioritized in evaluation. Transcriptomic analysis of whole blood over the course of infection revealed molecular signatures that can provide insights into the protective immune responses against P. falciparum infection. We identified genes whose expression patterns can help differentiate changes during acute P. falciparum infection and convalesces in varying transmission intensity. Taken together, this study predicts humoral and cellular signatures associated with the acquisition of naturally acquired immunity that can fairly distinguish individuals from two distinct transmission areas based on their immune profile
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    Potential Transmission Of Zoonoses Between The Human-Domestic-Wildlife Interface And Its Implication For Sustainable Health.
    (University Of Ghana, 2021-09) Amoah, L.A.O
    Zoonoses have been of great public health concern and a global phenomenon that continues to challenge both veterinary and human health systems. The risk of zoonoses is predicted to be higher in domestic settings where animals are constantly in close contact with humans and exposure to zoonotic pathogens is very high. In Ghana, some studies to identify zoonotic diseases transmitted by domestic animals or animals in the wild usually consider either the human-domestic interface or human-wildlife interface. Considering that in recent times diseases continue to emerge from unexpected reservoir hosts and through novel pathways, this study investigated zoonotic diseases that are potentially transmissible by domestic and wild animals to humans across the human-domestic-wildlife interface. It also assessed the awareness and knowledge of owners of companion animals on zoonoses in two human-dominated landscapes. The cross-sectional study involved fieldwork and laboratory processing of biological samples from dogs, cats, and rodents using molecular techniques. Specifically, Polymerase Chain Reaction (PCR) and gel electrophoresis were used to investigate the presence or absence of zoonotic pathogens in biological samples. In addition, questionnaires were administered to owners of companion animals in households and veterinary institutions in designated study areas. Secondary data on zoonotic diseases presented at selected health facilities were also accessed and evaluated to complement the field data. Overall, 404 animals comprising 185(45.8%) dogs, 15(3.7%) cats and 204 (50.5%) rodents were sampled from households, veterinary institutions and selected study sites. In all, seven (7) species of rodents were trapped with Arvicanthis niloticus and Praomys tullbergi identified as the dominant species in the urban and peri-urban areas, respectively. The prevalence of Babesia spp. was the highest (80.7%), followed by Staphylococcus spp. (72.5%) and the least was Ancylostoma spp. (18.1%). For zoonotic helminths (Toxocara canis, Strongyloides stercoralis and Ancylostoma spp.), a prevalence of 30.12% was recorded. The study found significant differences in the prevalence of T. canis (p<0.001), S. stercoralis (p=0.033), and Salmonella spp. (p<0.001), Staphylococcus spp. (p=0.017) and Babesia spp. (p=0.029) between the two human-dominated landscapes. Similarly, there were significant differences in the prevalence of T. canis (p=0.034), S. stercoralis (p<0.001) and Babesia spp. (p<0.001) between the households and veterinary institutions as well as among sampled animals (p<0.05). On the whole, 13.9% of sampled animals had a single or mono-zoonotic infection, while 80.9% were co-infected with multiple zoonotic pathogens. Additionally, medical records from Shai-Osudoku and Pentecost Hospitals revealed that helminth infections were the commonest zoonoses presented by clients, particularly those under 18 years old. Conversely, staphylococcal infections were the highest zoonotic infections reported by clients of the University of Ghana Hospital. Again, 33.8% of 230 respondents who participated in the survey owned companion animals for companionship or as part of the family. Remarkably, 38.9% of the respondents had never dewormed their companion animals. While 62% of respondents had vaccinated their animals, 10.1% did it over a year ago, implying that about 48.1% of these animals were at risk of infectious diseases and could transmit the same to their owners. Furthermore, significant positive associations were found between the educational level of respondents and the frequency of vaccinating pets (rs =0.254, p<0.001) as well as respondents’ knowledge of causes or sources of zoonoses (rs =0.141, p=0.049). On the contrary, there was a significant negative association between the frequency of deworming pets and the main reason for keeping such animals (rs =-0.203, p=0.011) besides the prevention of zoonoses (rs =-0.260, p=0.001). Findings from this study indicate companion animals and rodents are reservoir hosts to zoonotic pathogens of public health importance that can potentially be transmissible to their owners and the community. Also, because these animals are co-infected with multiple zoonotic pathogens, it suggests there could be serious implications for sustainable health, which SDG 3 seeks to achieve. Data from the animal interface and the medical records from the human interface indicate the potential transmission of zoonoses, especially helminthiasis, in the studied communities. In addition, the urban areas were identified to best support the potential transmission of zoonoses contrary to the peri-urban areas. Thus, active surveillance of zoonoses in animals in close contact with humans in our urban and peri-urban communities is urgently required. Again, respondents had some knowledge of zoonotic diseases from companion animals, although most were ignorant of zoonoses from rodents. Findings from the survey indicate that a high proportion of owners of companion animals in the study areas were engaged in activities that predispose them to zoonotic diseases. It is recommended that public education campaigns and awareness creation programmes using a one-health approach should be started in earnest to ensure the effective prevention and control of zoonotic diseases.
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    Martingale Hardy-Amalgam Spaces
    (University of Ghana, 2022-07) Bansah, J.S.
    In this work, we introduce the new spaces, Hs p;q; HS p;q; H_ p;q; Qp;q; Pp;q; called the martingale Hardy-amalgam spaces. We study some of the properties of these newly introduced spaces; two de_nitions of atoms are given and hence two atomic decompositions are given, dualities of these spaces are characterized and the martingale inequalities and embeddings of these spaces are also discussed. It is proved that the dual of Hs p;q; (0 < p _ q _ 1); is a Campanato-type space and the dual of Hs p;q; (1 < p _ q < 1); is Hs p0;q0 where (p; p0); (q; q0) are conjugate pairs. The variation integrable space Gp;q is also introduced and it is established that the jump bounded space BDp;q is the dual of Gp;q: To be able to characterize this duality, a larger space, which we denote by K(Lp;q; `r); is introduced, such that Gp;q can be embedded into. The classical Doob's martingale inequality is also extended from the classical martingale Hardy spaces to the newly introduced martingale Hardy-amalgam spaces. The Burkholder-Davis-Gundy inequality is also extended from the classical martingale Hardy spaces to the martingale Hardy-amalgam spaces as well as the convexity inequality and the concavity inequalities involving measurable functions. The classical martingale Hardy space embeddings are also extended to the martingale Hardy-amalgam spaces. The Davis decompositions of martingales in the classical martingale Hardy spaces are also extended to the martingale Hardy-amalgam spaces. As an application of the Davis decomposition and the Garsia space, a duality theorem for H_ p;q (1 _ p; q _ 2) is provided. Finally, the boundedness of martingale transforms between the martingale Hardy-amalgam spaces are also discussed. No data was collected for this study as the methodology used is purely theoretical in nature.