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Mechanistic modeling of crack propagation in hydraulically fractured reservoirs for predicting inter-well fracture communication during infill well stimulation
(Geomechanics for Energy and the Environment, 2026-04-20) Pidho, Justin Jordan; Wanasolo, William; Yan, Chuanliang; Cheng, Yuanfang
Inter well fracture communication is a persistent challenge in multi well infill stimulation, often reducing production efficiency and compromising reservoir integrity. This study develops a mechanistic framework based on the Extended Finite Element Method (XFEM) with phantom node enrichment to simulate multi fracture propagation between neighboring horizontal wells. The model couples poroelastic rock deformation, fracture-matrix fluid exchange, pressure dependent leak off, and fracture propagation governed by a traction-separation law, providing a fully integrated representation of hydraulic fracturing processes. Parametric analyses reveal that zero-stagger distance with simultaneous injection promotes complete fracture linking, while larger offsets or scheduled treatments mitigate communication through stress shadow effects. Increasing rock tensile strength enhances fracture repulsion and reduces tip to tip linking. Distinct pressure signatures differentiate linking fractures, which exhibit localized sagging, from non linking fractures with monotonic gradients. The framework was validated against Displacement Discontinuity Method (DDM) benchmarks, Kristianovich-Geertsma-de Klerk (KGD) analytical solutions, and field measured pressure data from the Daqing Oilfield, demonstrating strong goodness of fit and confirming model fidelity. This work finds useful application in designing perforation patterns, optimizing cluster spacing, and scheduling treatments in unconventional shale reservoirs. By enabling accurate prediction of fracture linking, coalescence, and repulsion, the framework provides practical guidance for maximizing stimulated reservoir volume while controlling unintended inter well interference.
A factory-level data-informed roadmap to industry 4.0 for low digital maturity steel manufacturing plants
(International Journal of Advanced Manufacturing Technology, 2026-04-25) Kangwagye, Samuel; Ssempijja, Maureen Nalubowa
This paper presents a factory-level, data-informed Industry 4.0 readiness and upgrade framework for steel manufacturing plants operating in low digital maturity environments, using Uganda as a representative case. Field data was collected at three medium-scale operational steel plants. Customized Digital Maturity Index (DMI) and cybersecurity risk (CSR) assessment criteria were developed and applied. Results show an overall DMI score of 1.8, indicating very low digital maturity with predominantly manual operations, absence of industrial robots, advanced automation, and integrated digital data systems. CSR assessment results show limited formal protection mechanisms. A phased, ROI-driven transition roadmap is proposed. A worked case using plant-level production data demonstrates that selective automation of four bottleneck stations could nearly double annual billet output and achieve an incremental payback period of approximately seven weeks under stated assumptions. Workforce transition modeling using a Markov approach indicates gradual role transformation over an expected horizon of about ten transition cycles rather than abrupt displacement.
Antimicrobial Activity of Isolated Compounds from Zanthoxylum gilletii Stem Bark Extract
(International Research Journal of Pure and Applied Chemistry, 2026-04-20) Niringiyimana, Eric; Twinomuhwezi, Hannington; Gumula, Ivan; Odokonyero, I; Byaruhanga, Ivan; Onen, Patrick
Background: Zanthoxylum gilletii, an important African medicinal plant, is widely used in traditional medicine for treating various ailments due to its rich phytochemical composition. However, despite its extensive ethnomedicinal applications, the specific bioactive compounds responsible for its antimicrobial properties remain insufficiently characterized. Aims: The study aims to isolate and characterize bioactive compounds from Zanthoxylum gilletii stem bark and evaluate their antimicrobial activity against selected bacterial and fungal pathogens. Methodology: Zanthoxylum gilletii stem bark was collected from Mabira Forest Reserve (0°23′54″N 33°0′59″E), Buikwe District, Uganda on 17th June 2022. The experiments were performed at the Department of Chemistry, Kyambogo University, between June 2022 and July 2023. Stem barks were shade dried, powdered, and extracted using Maceration technique with a mixture of methanol and dichloromethane (ratio 1:1) solvent. The extract was subjected to open column chromatography and identified using NMR spectroscopy and compared with literature information. Antimicrobial activity of crude extract and also the isolated compounds were assessed via disk diffusion against five bacterial and two fungal strains. Results: In this study, four known compounds: lupeol (1), stigmasterol (2), α-amyrin cinnamate (3) and α-amyrin acetate (4) were isolated from stem bark extracts of Zanthoxylum gilletii. This is the first-time compound 4 is reported in Zanthoxylum genus. The compounds had antimicrobial activities against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Enterobacter cloacae, Candida albicans and Aspergillus fumigatus. The extract and the compounds displayed inhibition against the microorganisms with diameters measuring 3.0±0.0 mm to 19.0±0.0 mm. The minimal inhibitory concentrations (MICs and MFCs) for active strains ranged from 6.25 to 150 mg/mL. Conclusion: The observed activities support the traditional use of this plant in treating various ailments by Ugandan communities.
Microbiological and chemical quality of raw milk, Bongo andyoghurt from diverse sources in Mbarara District, Uganda: a cross-sectional analysis of contamination and safety indicators
(Cogent Food & AgriCulture, 2026-04-12) Mugabe, Amos; Mugampoza, Ediriisa; Wacoo, Paul alex
This study assessed the microbiological and chemical quality of milk, Bongo, and yoghurt collected from different points along the dairy value chain in Mbarara district, Uganda, over three sampling rounds between October and December 2024. a total of270 samples were analyzed, comprising 162 milk samples from farms, collection centers, and processors, as well as 54 yoghurt and 54 Bongo samples from processors. Microbiological quality was evaluated using standard plate count methods to determine total viable counts (TVc), Escherichia coli, and yeasts and moulds, while Salmonella was detected qualitatively. chemical quality was assessed through ph and titratable acidity following iSo protocols. overall results showed that milk from informal collection centers had the highest contamination (TVc 8.73 log cFU/ml; E. coli 4.02 log cFU/ml).yeasts and moulds were highest (5.55 log cFU/ml) in yoghurt from small-scale processors. Salmonella was detected only in milk from farms and informal collection centers. Milk from formal farms had the highest ph (7.01), whereas yogurt from small-scale processors highest titratable acidity (0.93% lactic acid). Statistical analysis(one-way anoVa, Tukey’s test, p < 0.05) showed variation in quality along the dairy value chain hence the need for improved hygiene and processing practices, especially in informal sectors.
Multi-Country-multi-city characterisation of heat stress and exposure in Africa
(International Journal of Climatology, 2026-04-21) Morakinyo, Tobi Eniolu; Adeyeri, Oluwafemi E.; Daramola, Mojolaoluwa Toluwalase; Vishal, Bobde; Ishola, Kazeem Abiodun; Obe, Oluwafemi Benjamin; Eresanya, Emmanuel Olaoluwa; Akinsanola, Akintomide Afolayan; Onyutha, Charles; Ayugi, Brian Odhiambo; Nying'uro, Patricia
This study presents the first continent-wide assessment of long-term (1974–2023) summer heat stress in Africa using the Universal Thermal Climate Index (UTCI) derived from ERA5-HEAT reanalysis datasets. Employing a grid-specific definition of summer, we analysed UTCI trends across spatial (continental to city scale) and temporal (decadal to hourly) dimensions. While annual UTCI anomalies range 0.2°C–1.6°C, substantial intensification emerges at finer scales. The frequency, duration and spatial extent of ‘very strong’ (38°C–46°C) and ‘extreme’ (≥46°C) heat stress have increased markedly, particularly, in the Sahel. Heatstressed hours (UTCI>32°C) rose by 2%–25% across most countries, with extreme events doubling in 3–5 and 6–8days episodes. City-level analyses reveal escalating risks in large urban centres like Cairo, Lagos and Kano. As climate projections indicate further intensification, the findings underscore the urgent need for targeted heat-health adaptation and early warning systems to protect vulnerable populations across the continent.