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This paper aims to discuss about the benefits of Cu(NO₃)₂ applied in coating paint film that consists of plant extract from Cassia Alata. Cu(NO₃)₂ has been added to the coating paint film as a colour stabilizer and as an antifungal property by forming a zone of inhibition towards fungal growth.

The coating paint film resin consists of a mixture of poly (methyl methacrylate) (PMMA) and acrylic polyol. The coating paint film’s performances were observed in terms of visible optical and physical appearance.

When exposed to the fungus Trichoderma Sp., a zone of inhibition of 208 mm² was formed around the coating paint film and therefore it gave the coating paint films an antifungal property. The commission internationale de l’éclairage (CIE) L*a*b* colour coordinate system was used to identify the colour changes in the coating paint film and it was found that the addition of Cu(NO₃)₂ to the coating paint film has a better colour stability, as it has a lower standard deviation (STD) value of 6.46 than the pure dye coating paint film of 8.95. The gloss of coating paint film with the addition of Cu(NO₃)₂ was found to be have a more stable gloss based on its smaller STD value at both angles taken at 20° and 60°.

The Cassia Alata plant has different amount of antifungal properties based on location its growth.

The coating paint film developed in this study is suitable for indoor applications.

The plant extract from the Cassia Alata gives the coating paint film an antifungal property.

The purpose of this paper is to study the colour stability and water content resistivity of the green colour coating paint film (consisting of chlorophyll) during exposure to ultraviolet A (UV-A).

The natural green dye was prepared by immersing Cassia alata L. leaves in absolute ethanol. The extract was prepared in two batches of dye samples where one of it was a pure dye and the other was added with 3 Wt. % Cu(NO₃)₂ as an additive. Polymer blend as a binder was prepared by mixing poly(methyl methacrylate) (PMMA) and commercial acrylic polyol. The blended polymer was mixed with the natural dye in a specific ratio and applied as coating paint film on glass panel surfaces. The visible spectrum stability (colour stability) and water content resistivity of the coating paint films during exposure to UV-A were monitored.

Addition of Cu(NO₃)₂ had improved the colour stability of the coating paint film. Fourier transform infrared spectroscopy analysis showed that both coating paint films do not absorb water and are resistive to water content.

The ability of Cu(NO₃)₂ as an colour stability additive to the natural green dye applied in the coating paint film.

The coating paint film developed in this work is suitable to be applied on glass substrates.

The colour stability of the coating paint film was analysed by using the reflectance spectrum.

The effect of using microcrystalline cellulose (MCC) as an additive in coating paint films for non-stick coatings was studied in this work. This paper aims to discuss the benefits of MCC blended in the coating paint film that consists of poly(methyl methacrylate) (PMMA) and dammar.

PMMA and dammar mixed at a specific Wt.% ratio with xylene as its solvent. Two sets of mixtures were prepared, where one mixture contained MCC and another, without. The mixtures were applied to metal substrates as coating paint films. The performance of the non-stick coating paint film was observed through the adhesive test between adhesion layers on the coating paint film and also through the cross-hatch test for the adhesion of the non-stick coating paint film to the metal substrate. The results correlate with the surface roughness and glossiness tests.

The results showed that for the coating paint films, Sample B consisted of 80:20 Wt.% ratio of PMMA-dammar with an addition of 5 Wt.% MCC had an excellent performance as non-stick coating paint films. The MCC formed microparticles on the surface of the coating paint film sample and this causes the coating paint film samples with MCC to develop a rougher surface compared to the coating paint film without MCC. Sample B coating paint film had the highest average surface roughness (Ra) of 383 µm. The cross-hatch test showed the coating paint film with the addition of MCC had stronger adhesiveness on the substrate’s surface thus prevents the coating from peeling off from the surface.

The developed coating paint film in this study would be suitable for outdoor applications to prevent illegal advertisements and stickers.

MCC added to the coating paint film improves the surface performance as a non-stick coating.

Previous RMIL versions of the conjugate gradient method proposed in literature exhibit sufficient descent with Wolfe line search conditions, yet their global convergence depends on certain restrictions. To alleviate these assumptions, a hybrid conjugate gradient method is proposed based on the conjugacy condition.

The conjugate gradient (CG) method strategically alternates between RMIL and KMD CG methods by using a convex combination of the two schemes, mitigating their respective weaknesses. The theoretical analysis of the hybrid method, conducted without line search consideration, demonstrates its sufficient descent property. This theoretical understanding of sufficient descent enables the removal of restrictions previously imposed on versions of the RMIL CG method for global convergence result.

Numerical experiments conducted using a hybrid strategy that combines the RMIL and KMD CG methods demonstrate superior performance compared to each method used individually and even outperform some recent versions of the RMIL method. Furthermore, when applied to solve an image reconstruction model, the method exhibits reliable results.

The strategy used to demonstrate the sufficient descent property and convergence result of RMIL CG without line search consideration through hybrid techniques has not been previously explored in literature. Additionally, the two CG schemes involved in the combination exhibit similar sufficient descent structures based on the assumption regarding the norm of the search direction.

This paper aims to examine the effect of e-evaluation on work motivation among teachers during the Movement Control Order (MCO) in COVID-19 and determining the mediating role of stress.

The study is designed using a causal research design to examine the cause-effect relationship between the study variables. The study sample consists of 595 school teachers selected via convenient sampling. Quantitative data are collected from an online survey through the questionnaires with demographic, stress, e-evaluation and work motivation developed by the researchers were distributed during the MCO period. To test the model, structural equation modelling (SEM) was applied by using AMOS 21.

The results indicated that the e-evaluation, stress and work motivation of teachers during the MCO were conducted at a moderate level. The stress relationship with work motivation of teachers was also weak and showed a negative relationship, while e-evaluation and work motivation showed a strong relationship. The results of the SEM analysis revealed that the model fit was achieved with RMSEA = 0.07, GFI = 0.96, CFI = 0.98, TLI = 0.97, ChiSq/df = 4.30 and p = 0.00. In addition, there was no role of stress as a mediator in the relationship between e-evaluation and work motivation and e-evaluation contributed 54% to work motivation.

This study underlines our contention that teachers’ work motivation correlated positively with their e-evaluation. The findings suggest that teachers’ stress cannot mediate the relationship between e-evaluation and work motivation. The limitations of the study include the convenience sampling, non-probability sampling technique, not chosen at random and undermines the generalizations from sample to the population.

The results provide a useful framework to teachers for the successful implementation of e-evaluations in their instruction to enhance their work-motivation.

There is a lack of e-evaluation studies in teacher education and teaching strategies, and the correlation between e-evaluation and work motivation during COVID-19 pandemic is often absent.

Against the background that Ghanaians seldom purchase insurance policies, the purpose of this paper is to investigate the determinants of life insurance uptake among male and female household heads in Ghana.

The study employs data on 775 male and 233 female household heads from the sixth round of the Ghana Living Standards Survey. Adjusted Wald test statistics and logistic regressions are employed for the empirical estimations.

Results from the adjusted Wald test show that the sampled male household heads significantly differ from their female counterparts in terms of the selected socioeconomic and demographic characteristics. Though ill health status, higher wealth, being self-employed or in wage or salaried employment and residing in either of the three northern regions (upper east, upper west and northern regions) in Ghana broadly affect the demand for life insurance among both male and female heads, other factors are peculiar to either parties. Particularly, whereas female heads who are married and those with more dependants have a higher propensity of purchasing life insurance policies, their male counterparts with higher education are more likely to buy life insurance policies.

The paper adds to the paucity of cross-sectional studies on life insurance demand in Africa.

Based on the explored determinants, insurers could better regulate the purchase of their products by taking into consideration the gender differences to maximize their sales and enhance economic growth and development.

This paper explores the gender dynamics in the determinants of life insurance demand in a developing country, Ghana. Besides, findings from related literature are reported to be mixed. Though the current paper is not wholly nationally representative, it utilizes data from across all the ten administrative regions of Ghana. To the best of the authors’ knowledge, no prior study has been conducted in this manner.

This study is a pre-COVID-19 exposition of the existing situation about external debt-GDP relationship, incorporating corruption into the hypothesis, making South Africa the object of the study. The aim is to examine the causal relationship between corruption, economic growth and external debt, and in the end proffer solutions to the problems arising therefrom.

The study employed ARDL technique on time series data running from 1990 to 2019 with real gross domestic product as the dependent variable and external debt, external debt servicing, corruption, inflation and capital formation as regressors. Necessary tests that include unit root, cointegration, CUSUM and CUSUMSq, normality, serial correlation and heteroscedasticity were performed on the model.

The study shows that corruption, inflation and external debt servicing exert negative influences on economic growth while the effect of investment on growth was positive. External debt's effect in the short run was positive while its long-run effect on growth was negative. Among other things, the need to improve and strengthen public institutions in addition to targeting tax evaders and avoiders for increased government revenue were emphasized.

The study incorporates corruption into the country specific debt-GDP debate as against earlier studies that excluded corruption in their time series analysis or that were cross-country based. The authors also exposit the existing knowledge of the debt-GDP hypothesis before the outbreak of COVID 19 pandemic. This is expected to serve as a precursor to subsequent studies on the rising debt of South Africa during and after the pandemic.

The purpose of this paper is to examine the role external debt and foreign direct investment play in influencing financial development in Africa.

Annual data on external debt, foreign direct investment and financial development were extracted from the World Bank World Development Indicators from 2002 to 2015. The data employed were analysed within causal research design and the dynamic panel using generalized method of moment estimation approach.

The findings revealed that external debt and foreign direct investment have a significant positive relationship with financial development in African economies. Governments of the sampled economies should enact policies that would help attract high level of foreign direct investment as it contributes positively to financial development. Finally, governments of the sampled African economies should ensure foreign direct investment and external funds borrowed are channelled to productive sectors.

The paper analysed the relationship between external debt, FDI inflows and financial sector development. The paper is the first in terms of such analysis within the framework of the dual-gap framework, which is the first time in these kinds of studies. Previous studies have concentrated on the effect of financial sector on FDI and not the other way around.

This study aims to examine the symmetric and asymmetric impact of external debt on inflation in Sudan from 1970 to 2020 within a multivariate framework by including money supply and the nominal effective exchange rate as additional inflation determinants.

The authors utilize an Auto Regressive Distributed Lag (ARDL) model to examine the symmetric impact of external debt on inflation, while the asymmetric impact is examined using a Nonlinear ARDL (NARDL) model. The existence of a long-run relationship between inflation and external debt is tested using the bounds-testing approach to cointegration, and a vector error-correction model is estimated to determine the short parameters of equilibrium dynamics.

The linear ARDL model results show that external debt has no statistically significant impact on inflation in the long run. On the contrary, the results of the NARDL model show that positive and negative external debt shocks statistically affect inflation in the long run. The estimated long-run elasticity coefficients of the linear and nonlinear ARDL models reveal that the domestic money supply has a statistically significant positive impact on inflation. In contrast, the nominal effective exchange rate has a statistically significant negative impact on inflation.

The reliance on symmetric analysis may not be sufficient to uncover the existence of a linkage between external debt and inflation. Proper external debt management is crucial to control inflation rates in Sudan.

To date, no empirical study has assessed the external debt-inflation nexus and its potential asymmetry in Sudan, and the current study aims to fill this gap in the literature.