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Covid-19 Vaccine Acceptance and Risk Perception in Ghana: Insights from A Study on Tertiary-Level Students and Surrounding Residents in Kumasi
(Journal of Science and Technology, 2024) Darko, Samuel Nkansah; Boahen, Kennedy Gyau; Okyere, Portia Boakye; Addo, Christopher N. K.; Ameyaw, Afuaa Janet; Adjei, Emmanuel; Hayford, Manuella; Anhwere, Naomi Efua; Kwarteng, Sandra Abankwa
The introduction of COVID-19 vaccines in sub-Saharan Africa has been met with mixed feelings. In Ghana, several concerns were raised about the potency and side effects of the COVID-19 vaccine. We investigated the acceptance and risk perception of students on the KNUST campus and the residents of the surrounding communities to assess the risk factors that will influence heir willingness or unwillingness to be vaccinated in the government’s quest to get its citizens vaccinated. A well-structured questionnaire was administered online and through face-toface interviews to survey 3332 respondents between the periods of March 15 and May 28, 2021. Chi-square analysis was used to show the association between the sociodemographic characteristics and, the acceptance and risk perception of the COVID-19 vaccine. Logistic regression analysis was used to explain the relationship between the acceptance and risk perception of the COVID-19 vaccine and the various socio-demographic characteristics. Out of 3323 respondents, 1,703 (45.23%) were hesitant whiles 64.39% of 3311 indicated they would accept being vaccinated. In a multivariate analysis, the age range of 31 to 40 years, being male, having secondary level education, and having a previous vaccination post-childhood immunization increased the likelihood of vaccine acceptance. More than half of the students of KNUST and inhabitants around the campus are likely to acceptant the COVID-19 vaccine. However, adequate and timely information is needed to educate prospective vaccine recipients with tertiary level education to better the level of acceptance and address misinformation about vaccines and promote individual and population-level benefits of vaccination
Cutting resistance assessment for three varieties of cassava roots
(Journal of the Ghana Institution of Engineering, 2023-11-27) Amoah, Francis; Asante, Eric Amoah; Amuaku, Randy; Bobobee, Emmanuel Yaovi Hunnuor
In this study, a model has been developed to assess the peel and root resistance to cutting. The evaluation was done with knife thicknesses of 1.0 mm, 1.5 mm and 2.0 mm using Duade kpakpa, Dudze and Sika bankye cassava varieties as experimental samples for three postharvest delays. The knife penetrated the tuber at 50 mm, 100 mm and 150 mm away from the proximal end. An average peel thickness obtained was in the range of 1.81 mm – 3.01 mm. The average diameters recorded ranged from 52.52 mm to 60.40 mm. The cutting resistance assessed for the Duade kpakpa, Sika bankye and Dudze cassava peels were 44.85 N, 50.01 N and 53.53 N, respectively with no significant differences (p < 0.05). The penetration resistance of the tuber decreased with increasing postharvest delay and increased with increasing knife thickness. The effect of the treatments on the response variables evaluated by factorial analysis showed that significant differences generally decrease with increasing interaction. Comparing the results, cutting resistances of 229.02 N, 223.09 N and 204.43 N in maximum were obtained for the Dudze, Sika bankye and Duade kpakpa cassava roots, respectively. The quantitative assessment by the PLSR model under the knife thicknesses (R2 = 0.9689; RMSE = 2.1020) was significantly better than the PLSR model under postharvest delay (R2 = 0.7845; RMSE = 4.0183). The technique employed in assessing the cutting resistance emphasized the cultivar differences and provided a measuring sequence and outstanding quantitative analysis.
Development and evaluation of agro-waste composite for sound insulation
(Journal of the Ghana Institution of Engineering, 2023-11-30) Amuaku, Randy; Amanor, Godwin K.; Adu-Gyamfi, Fehrs; Asante, Eric Amoah; Kweitsu, Eric; Opare, Samuel
The palm kernel shell is a by-product of palm kernel oil production and is commonly used in the natural biomass energy industry. Coconut husk fibre is extracted from the coconut fruit. To find a use for palm kernel shells and coconut husk fibre, a composite insulator plate was developed by the addition of a binder through a process of grinding, sieving, mixing, heating, hot-pressing and cooling in a mould. An Ahuja speaker AU60 was fixed at one end of a baffled tube and a sound level meter was placed 2 m away from the output to record sound transmission loss at 5s intervals for twenty minutes. The plates of 3, 4, 5, and, 6 mm thickness were fixed in the baffled tube at a distance of 475 mm away from the input one after the other to filter the input sound. The results showed that the setup without a composite insulator recorded the highest noise of 226.8 dB. The average recorded sound transmitted loss was 185.40, 72.47, 74.54, 76.06, and 82.85 dB for no insulator, 3, 4, 5 and, 6 mm composite insulators respectively. The introduction of the 3, 4, 5, and, 6 mm thickness composite insulators resulted in 55.3 %, 59.0 %, 59.8 % and 60.9 % reduction in noise level. The application of agro-waste composite material as a sound insulator in a baffled tube has proven to be effective by 58.7 % on average. The study has confirmed that agro-waste materials can be used in sound insulation applications.
Stochastic Optimal Selection and Analysis of Allowable Photovoltaic Penetration Level for Grid-Connected Systems Using a Hybrid NSGAII-MOPSO and Monte Carlo Method
(International Journal of Photoenergy, 2023) Abubakar, Ali; Borkor, Reindorf Nartey; Amoako-Yirenkyi, Peter; 0000-0002-5721-4638
Generally, the main focus of the grid-linked photovoltaic systems is to scale up the photovoltaic penetration level to ensure full electricity consumption coverage. However, due to the stochasticity and nondispatchable nature of its generation, significant adverse impacts such as power overloading, voltage, harmonics, current, and frequency instabilities on the utility grid arise. These impacts vary in severity as a function of the degree of penetration level of the photovoltaic system. Thus, the design problem involves optimizing the two conflicting objectives in the presence of uncertainty without violating the grid’s operational limitations. Nevertheless, existing studies avoid the technical impact and scalarize the conflicting stochastic objectives into a single stochastic objective to lessen the degree of complexity of the problem. This study proposes a stochastic multiobjective methodology to decide on the optimum allowable photovoltaic penetration level for an electricity grid system at an optimum cost without violating the system’s operational constraints. Five cutting-edge multiobjective optimization algorithms were implemented and compared using hypervolume metric, execution time, and nonparametric statistical analysis to obtain a quality solution. The results indicated that a Hybrid NSGAII-MOPSO had better convergence, diversity, and execution time capacity to handle the complex problem. The analysis of the obtained optimal solution shows that a practical design methodology could accurately decide the maximum allowable photovoltaic penetration level to match up the energy demand of any grid-linked system at a minimum cost without collapsing the grid’s operational limitations even under fluctuating weather conditions. Comparatively, the stochastic approach enables the development of a more sustainable and affordable grid-connected system.
3-Monochloropropandiol and glycidyl esters in heat-processed oil-based food products: Exposure and risk
(Applied Food Research, 2024-06) Yabani, Daniel Sitsofe; Ofosu, Isaac Williams; Ankar-Brewoo, Gloria Mathanda; Lutterodt, Herman Erick; 0000-0001-5442-6654; 0000-0002-9553-0834; 0000-0001-8574-3409; 0000-0001-7015-7597
Fatty acid esters of 3-monochloro-1,2-propanediol (3-MCPDE) and glycidol (GE) are potentially harmful heatinduced contaminants produced during food processing. In this study, 100 heat-treated oil-based food samples covering fried, smoked, grilled, and baked food groups were collected in Koforidua, Ghana and analysed for the two esters using gas chromatography-mass spectrometry. The dietary exposures were estimated by a probabilistic approach using Monte Carlo Simulation. Levels of 3-MCPDE and GE in the foods ranged from
Economic empowerment among female shea actors: the case of Savelugu District, Ghana
(Cogent OA, 2024) Adom-Asamoah, Gifty; View this author’s ORCID profile
The shea industry is a catalyst for the economic empowerment of women engaged in this sector. However, we do not know the extent to which women actors are economically empowered along this value chain, and the factors impeding their empowerment. Addressing this is crucial to developing policies in advancing the economic empowerment of female shea actors. This study aims to assess the extent to which the shea industry economically empowers female shea actors. We utilized a convergent mixed-methods approach, gathering quantitative data from 384 female shea actors (including producers, collectors, and marketers) and qualitative data from 12 experienced older women in the industry, making an overall sample of 396. The qualitative data underwent thematic analysis, while the quantitative data were subjected to the non-parametric Kruskal-Wallis test to compare the level of economic empowerment among the three groups of shea actors. We found significant differences among the three groups of shea actors (χ2 (2) = 75.266, p = 0.000). Collectors had a mean rank of 236.60, marketers had a mean rank of 131.24, and producers had a mean rank of 205.31; showing economic empowerment varies among the shea actors. However, they face challenges of inaccessibility to land, finance, and markets, as well as inadequate storage facilities that affect their operations. We recommend that the shea actors join or form groups to increase their access to loans, and control over prices, while development agents (both statutory and non-statutory) must improve access to lands, finance, and storage facilities.
A comparative study of Ghanaian propolis extracts: Chemometric analysis of the chromatographic profile, antioxidant, and hypoglycemic potential and identification of active constituents
(Scientific African, 2023-11) Amankwaah, Frederick; Addotey, John Nii; Orman, Emmanuel; Adosraku, Reimmel; Amponsah, Isaac Kingsley; 0000-0002-4372-3992
Diabetes is a disease characterized by high post-prandial glucose levels, which lead to other complications such as peripheral end organ damage. The use of enzyme inhibitors in the management of Type-2 diabetes ensure the control of blood glucose levels via the control of carbohydrate metabolism. The use of standard agents such as acarbose is associated with unwanted side effects hence the need to investigate other sources of antihyperglycemic agents. Propolis, a natural substance from bees, possesses diverse biological activities including antioxidant, antimicrobial and antidiabetic properties. However, the phytochemical content of propolis and its extracts may vary depending on the geographical area, the solvent of extraction and type of bees. This study represents the first attempt to compare different extracts of propolis from the same source in sub-Saharan Africa. In this study, the effect of solvent and source of Ghanaian propolis on parameters such as the total phenolic and flavonoid contents, chromatographic profile, antioxidant and α-amylase inhibitory effects were investigated with the aim of identifying and characterizing the most promising extract, which could be of direct or indirect benefit in the management of Type-2 diabetes. Combinations of water, ethanol-water and ethanol extracts were prepared from propolis from three regions. Phytochemical screening was performed on the extracts after which the Folin Ciocalteu method and aluminum chloride colorimetric assay were used to estimate the total phenolic and flavonoid contents respectively. Antioxidant potential of extracts was estimated using DPPH and phosphomolybdenum assays. In-vitro α-amylase inhibition assay was used to investigate hypoglycemic effect of the extracts. Statistical tools such as ANOVA, principal component analysis, hierarchical cluster analysis employed to determine sources of variations within the data obtained, to classify the extracts based on activity and to predict the most effective extract. This extract was then subjected to UHPLC-Q-TOF MS/MS and GC–MS techniques to characterize the constituents. Chemometric analysis of the data obtained showed that the variations in the data could be explained by both propolis source and extraction solvent. Though ethanol extracts generally contained more constituents, the more notable activities were in the ethanol-water extracts. The ethanol-water extract of Bono East propolis (EWBE) was the most potent DPPH radical scavenger (IC50 of 149.37 ± 2.90 µg/mL as compared to 116.60 ± 0.93 µg/mL GAE standard). It was also one of the three extracts which were more potent than acarbose (369.89 µg/mL) in the α-amylase inhibition assay. The predominant constituents from the LC-MS dereplication of EWBE were caffeic acid and flavonoid derivatives whilst 5,5-dimethyl-1-oxa-5 silacyclononanone-9 was the most significant active constituent identified through the GC–MS analysis. The identified constituents are known to have strong antioxidant and antidiabetic properties. The effects of source and solvent of extraction on the biological and physicochemical properties of propolis in Ghana have been quantified using statistical tools. The combined biological effects of propolis suggest a possible role in their usage in the management of type-2-diabetes and its related complications. Ethanol-water extracts were the most promising with EWBE showing the strongest antihyperglycemic activity. Such extracts represent leads towards further research into toxicity and formulation in order to develop safe and useful products for the management of type-2 diabetes.