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Item3D Electrospun poly L-lactic acid nanofibrous structures coated with regenerated silk fibroin and silver nitrate for burn wounds(Makerere University, 2026)Pediatric burn victims, who are the majority in Uganda, are treated with cotton gauze embedded with topical creams that require painful, frequent changes because of their adherence tendency due to absorption properties. This research developed a 3D-ES poly L-lactic acid (PLLA) nanofibrous structure coated with antibacterial properties that is also biocompatible and biodegradable. An optimized pristine 3D-ES structure had a height of 23.58 mm and a fiber diameter of 0.77 ± 0.05 µm (p > 0.05), suggesting uniform fiber diameters. It had a contact angle of 120°, 40.3% in vitro degradation, and 480.29% fluid take-up on Day 4. No cytotoxicity was observed by Lactate dehydrogenase (LDH) release assay, and cells adhered and grew, indicating biocompatibility. The 3D-ES structure was coated with regenerated silk fibroin (RSF), whose optimized extraction process was based on Activity-Based Costing (ABC) accounting for the total cost of producing 1 g of RSF, which cost $ 100.06 compared to the $379.58 cost of 1 g of Lyophilized RSF. With optimized spray parameters, silver nitrate (AgNO3) was coated onto the 3D-ES structure. Prior, the minimum inhibitory concentration (MIC) and maximum bactericidal concentration (MBC) of 0.5 mg mL-1 AgNO3 were analyzed and recorded as the 1st and Neat for all standard and clinical isolates for S. aureus and E. coli. The zone of inhibition (ZOI) decreased with increasing serial dilution, with the widest clearance being 24 mm for SE. coli clinical isolate. Overall, the 3D-ES PLLA structure coated with RSF and AgNO3 was biodegradable, biocompatible, and had antibacterial properties. This research introduces the potential of using 3D-ES drug-loaded structures as potential wound dressings.
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ItemModelling of the Behavior of the Heated Crude oil in the East African Crude oil Pipeline.(Makerere University, 2026)The East African Crude Oil Pipeline (EACOP) is designed to transport waxy crude oil from Uganda to the port of Tanga, Tanzania. Uganda's crude oil has a uniquely high pour point of 40°C, making active heating necessary for flow assurance. This research developed an integrated numerical model (Finite Element Method (FEM) and Computational Fluid Dynamics (CFD) in ANSYS) to simulate the behavior of heated crude oil in the East African Crude Oil Pipeline (EACOP) under normal and failure scenarios. The specific objectives were to quantify radial heat loss across the pipe cross‑section for different crude oil fill levels (full, ¾, ½, ¼ bore) and ambient soil temperatures (18 °C to 35 °C), to simulate temperature, velocity, and viscosity profiles along an 18 m pipeline section for five scenarios (normal operation: 50 °C inlet temperature with 70 °C heat trace , heating failure at 50 °C and 40 °C inlet temperature) and to assess the impact of a 20 mm wax layer on those profiles under heating failure at the same two inlet temperatures. The key findings were firstly, the polyurethane foam (PUF) layer contributed 97.8 % of the total thermal resistance, heat loss varied by 32.8 % across the soil temperature range and fill level had a negligible effect when crude oil was present in the pipe. Secondly, under normal heating, the temperature drop was only 2‑3 °C over 18 m and viscosity remained constant; without heating and with a 40 °C inlet, the crude oil cool ed below its pour point (36.5 °C) and viscosity increased by 300 %. Thirdly, a 20 mm wax layer caused a 31‑47 % velocity increase: however, while offering a minor thermal insulation (10 % reduction in cooling rate). The FEM cross‑sectional results were validated against the analytical multi‑layer conduction solution with a deviation <0.2 %. The study concluded that EACOP’s heated and insulated design is sound, but operational success requires maintaining the inlet temperature above 50 °C, proactive pigging before wax reaches 20 mm, and dynamically adjusting heating power according to soil temperature variations.
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ItemDevelopment of a Single - Phase Power Quality Monitoring System(Makerere University, 2026-06-10)Electricity is crucial for the social, cultural, and overall well-being of Uganda. However, the absence of real-time monitoring and reporting on single-phase electricity networks exacerbates downtime and power instability, resulting in reduced productivity, equipment damage, and revenue loss. The existing call center structure, which depends on social media feedback and phone calls to the Supervisory control and data acquisition (SCADA), is susceptible to human error, process delays, and is labor-intensive in managing reference numbers. This study aimed to develop a prototype of an automated voltage quality reporting system with location updates. The conceptual framework was employed to visually represent the relationships between various concepts and variables. A comprehensive literature review of related studies and system development life cycle (SDLC) models was conducted to inform and guide the research. Methods were developed to address the research questions and to guide activities to fulfill the objectives' requirements. Data were gathered using measurement instruments from a sample area of single-phase households, with a focus on shops for ease of accessibility. The findings were subsequently employed to benchmark the study's test setup. The data collected from the sample area closely aligned with the test bench results, exhibiting only minor deviations, which indicated that the trends observed in the test bench were consistent with those in the sample area. The hardware and software were assembled and calibrated, resulting in a functional singlephase power quality monitoring system, with reports and alerts accessible online and on mobile devices. The developed prototype exhibited hardware and software configurations analogous to those documented in comparable studies. The study recommended integrating the system with an existing powermeter for regular power supply to prevent misreporting of power failures when customer units are depleted. Further research recommends embedding of algorithms and AI tools for designing power distribution topologies, promoting continuous improvement within the energy sector.
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ItemInvestigating the influence of masonry infill walls on the seismic response of reinforced concrete frame structures in Uganda(Makerere University, 2026)This study investigates the influence of masonry infill walls on the seismic response of Reinforced Concrete frame structures in Uganda, where current seismic design codes lack explicit provisions for infill wall and RC frame interactions. The study develops a site-specific design response spectrum for Uganda’s highest seismic zone. Finite element modelling in ABAQUS was employed to simulate the detailed nonlinear in-plane behaviour of infilled and bare RC frames. For broader parametric studies across varying building heights and infill types, like, clay bricks and solid concrete blocks, the equivalent diagonal strut method was implemented in ETABS. Model validation was conducted against established experimental results from pseudo-dynamic tests, ensuring accuracy in displacement, drift, and base shear predictions. Nonlinear static pushover analyses were performed to evaluate seismic performance indicators, including lateral displacement, storey drift, base shear capacity, and stiffness contribution. Results indicate that concrete block infills, owing to their higher compressive strength, provide greater initial stiffness and higher base shear capacity than clay brick infills. However, stiffness contribution decreases with increasing building height, reducing the relative benefit of infills in taller frames. Infill walls significantly reduced displacement and storey drift across all configurations, while Base shear was increased. Displacement was reduced by 80% for the concrete infill in the 2-storey structure and by 73 % for the clay infill. However, the stiffness contribution decreased as building height increased. This is observed by concrete infill reducing displacement by 79.7% in a 2-storey structure, but reducing it by 50% in a 10-storey structure. This research, therefore, provides region-specific evidence for the inclusion of masonry infill effects in seismic design.
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ItemEncapsulated and non-Organic Fertilizers for water retention and controlled nutrient release.(Makerere University, 2026-02)Declining soil fertility, low nutrient-use efficiency, and heavy dependence on imported synthetic fertilizers remain critical constraints to agricultural productivity in Uganda. This research developed and evaluated advanced organic fertilizers derived from biochar-blended compost (BBC), specifically focusing on two engineered derivatives: Encapsulated Biochar-Blended Compost (EBBC) and Nano-Biochar-Blended Compost (Nano-BBC). An optimized co-composting matrix (60% Tithonia diversifolia and 5.7% rice husk biochar) was established using Response Surface Methodology and Central Composite Design. The quadratic models developed for nitrogen, phosphorus, and potassium were highly significant (F-values of 33.70, 50.64, and 86.60, respectively) and exhibited a non-significant lack of fit (p < 0.05). Model robustness was confirmed by high coefficients of determination (R2 ≥ 0.97) and adjusted R2 ≥ 0.94, and low coefficients of variation (3.24%–6.24%), indicating high reproducibility. Tithonia diversifolia most influenced N and K enrichment, while P availability depended on quadratic effects of both substrates. The enriched mature compost served as the base for enhancements. Nano-BBC synthesis was optimized via high-energy ball milling, and a reduced quadratic model identified the milling solvent mass and ball-to-powder ratio as key factors for particle size reduction. Chitosan–starch biopolymer encapsulation further enhanced performance. Under simulated 20-mm rainfall, EBBC reduced leachate volume to 6.5 mL (65% less than conventional BBC and mineral fertilizers) while eliminating nitrate-N leaching. Nitrogen-release assays showed controlled release: EBBC pellets released 56.9–70% of total N over 30 days via Fickian diffusion, unlike uncoated BBC, which exceeded 100% by day 25 via non-Fickian kinetics. EBBC also improved soil moisture retention in sandy loam to 4.4% at 30 days via hydrogel effects. In semi-field Zea mays L. (Maize) trials under drought, EBBC produced the highest plant height and shoot biomass, outperforming BBC, Nano-BBC, and synthetics. All formulations met FAO/EU heavy-metal thresholds. This scalable, climate-smart framework transforms organic waste into high-performance fertilizers, synchronizing nutrient delivery with drought resilience in Uganda.