Baze University is a private tertiary institution located in Abuja, Nigeria, it was established in 2011. It is the best private university in Nigeria and 3rd best in the whole country offering higher level standard education of British quality.
Background: The construction industry is one of the most hazardous sectors globally, responsible for a disproportionate share of work-related injuries and fatalities. Construction health and safety (H&S) training is widely recognised as a critical component for improving workers' H&S competence and reducing accident rates. Despite extensive investment in training programmes, research indicates that learning effectiveness varies across construction firms and may be associated with differences in training design and organisational context. However, empirical understanding of whether firm size moderates the relationship between specific training design dimensions and learning effectiveness is limited. Objective: This study investigated the relationships between training design dimensions (training content relevance, facilitator competence, opportunity for practice, and learning environment) and learning effectiveness in construction H&S training while assessing the moderating role of firm size. Methods: A cross-sectional study was conducted with 80 construction professionals from medium- and large-scale firms. Data were collected using 5-point Likert scales to measure training design dimensions and learning effectiveness. Correlation analysis, multiple regression analysis, and moderation analysis using PROCESS were performed to test the hypothesised relationships. Results: Multiple regression showed that the four training design dimensions jointly explained 64% of the variance in learning effectiveness (R2 = 0.64, adjusted R2 = 0.62), with all four dimensions showing significant positive associations. Moderation analysis showed that firm size significantly moderated the relationship between training design quality and learning effectiveness (interaction B = 0.19, p = 0.033), with a stronger conditional effect among large firms (b = 0.62) than medium-sized firms (B = 0.43). Conclusions: This study extends the training effectiveness literature by showing that the relationship between training design quality and learning effectiveness varies according to organisational context, with firm size representing a potential boundary condition.
The migration of contaminants through inactive supply wells (ISWs) has drawn significant scrutiny because these wells can act as preferential flow pathways for contaminant transfer between aquifers. Declines in groundwater levels and clogging around ISWs can significantly reduce flow rates through these wells. Moreover, these wells can be surrounded by a finite-thickness skin, such as a gravel pack, and physical and biochemical clogs. Nevertheless, the impacts of fluctuating flow rates and the presence of a skin zone on contaminant migration through ISWs have not been exhaustively investigated. This study addresses this critical gap by initially fitting observational data from fieldwork carried out in California, USA, to characterize the variability in flow rates. Subsequently, a semi-analytical model incorporating both variable flow rates and skin effects was developed to elucidate contaminant migration. When benchmarked against a numerical solution, the approach exhibited superior accuracy and robustness. Several noteworthy findings emerged. First, the proposed exponential function precisely captures the variability in flow rates. Second, even minor alterations in the power index λ lead to substantial changes in breakthrough curves (BTCs), underscoring the high sensitivity of contaminant migration to variable flow rates. Third, increased dispersivity or reduced effective porosity within the skin zone accelerates contaminant migration. Furthermore, the contrast in dispersivity between the skin and aquifer leads to sharp changes in the spatial distribution of contaminants at their interface, which affects contaminant migration potential. Thus, variations in flow rates and skin effects profoundly influence contaminant migration through ISWs and must be rigorously considered in cross-contamination assessments.
This study investigated the synthesis and application of a sulfonated heterogeneous solid acid catalyst derived from a ripe-unripe plantain peel mixture for the esterification of waste cooking oil (WCO). The catalyst was prepared by carbonizing the dried plantain peel mixture at 550 degrees C for 2 h before being sulfonated with concentrated sulfuric acid. Analytical techniques such as FTIR, SEM/EDX, XRD, XPS, and BET/BJH were used to characterize the developed catalyst. WCO esterification was modeled and optimized using a central composite design of response surface methodology. Characterization revealed that the synthesized catalyst is a crystalline material with dominant phases of K2Ca(SO4)2 & sdot;H2O and K2SO4. BET surface area of 49.3 m2/g and average pore diameter of 6.15 nm demonstrated the mesoporous nature of the developed catalyst. FTIR, XPS, and XRD analyses confirmed the successful incorporation of sulfur-containing acidic groups, primarily-SO3H, on the surface of the catalyst. At the optimized conditions of 60 degrees C reaction temperature, 62 min reaction time, 10.8:1 methanol/WCO, and 3.5 wt% catalyst amount, the esterification achieved 90.5 +/- 1.64 % FFA conversion. A possible esterification reaction mechanism was proposed. Reusability of the catalyst was successfully demonstrated after 5 reaction cycles, with a conversion of 76.4 %. The findings from this study highlight that the synthesized catalyst derived from plantain peel, is capable of serving as a solid-acid catalyst for pretreatment (FFA esterification) of WCO prior to base-catalyzed transesterification.
To support the global transition from fossil fuel to cleaner energy sources, this study conducts the techno-economic analyses of four hybrid energy systems: Grid/photovoltaic (PV)/Hydro, PV/Hydro, Grid/Hydro, and Grid/PV for sustainable rural electrification in Nigeria. While hybrid energy systems using solar PV, wind, and diesel have attracted credible attention, this work highlights the untapped potential of run-of-river hydro-power, a carbon-free resource with widespread networks across the globe. The analyses using the HOMER pro software tool incorporated the incessant utility grid interruption characteristics of developing countries. Results reveal that the hybrid Grid/PV/Hydro system is optimal in meeting the community’s electricity demand of 2,822.20 kWh/day at the lowest net present cost of 9,160,308.00 and levelized cost of energy of0.13/kWh. The micro-hydro power plants, solar PV, and grid, respectively, contribute 80.90
Health economics is crucial for optimizing resource allocation and achieving equitable health outcomes in Africa. This study reviewed the historical evolution and current state of health economics in Africa, focusing on healthcare financing mechanisms, resource allocation strategies, and policy interventions. Data from peer-reviewed articles, research reports, and grey literature were synthesized from databases like PubMed, Scopus, Google Scholar and African Journals Online (AJOL). While healthcare financing dominated the literature, this review also covers resource allocation and broader health economics, highlighting key gaps in African research. Findings highlight significant challenges such as low public expenditure, high out-of-pocket costs, and inadequate insurance coverage. Out-of-pocket payments constitute over 40
