African Scientific Reports is a peer reviewed, open access, inter- and multidisciplinary scientific journal that is dedicated to expanding access to African research, increasing intra-African scientific collaboration, and building academic research capacity in Africa. The journal aims to provide a modern, highly-visible platform for publishing pan-African research and welcomes submissions from all areas of the natural sciences, psychology, medicine and engineering. With the idea that making research openly available to the public promotes better global knowledge exchange, this journal offers direct open access to its contents, i.e., all the articles published in this journal are free to access immediately from the date of publication. ASR is available in print and online. The language used in this journal is English.
Bioelectrochemical transformation of synthetic waste from the Vaal region: effects of acetic acid, sugar, and salt on biogas production and electricity generation using a microbial fuel cell
Section: ENGINEERING SECTION Categories: BIOLOGICAL SCIENCES, CHEMISTRY, ENGINEERING Keywords: Biogas, Microbial Fuel Cell, Vaal region, Wastewater Disciplines: Chemical Engineering This study investigated the effects of common domestic organic modifiers---acetic acid, brown sugar, and table salt---on the electrochemical, physicochemical, and bioenergetic characteristics of low-strength synthetic wastewater in a microbial fuel cell (MFC). Four wastewater matrices representing sewage from the Vaal region were prepared and maintained under anoxic conditions for 30 days. Maximum biogas production of 189 ppm and electrical output of 164 mV were recorded, indicating substrate-selective microbial activity. Fourier transform infrared spectroscopy (FTIR) confirmed structural changes in functional moieties in suspended solids and showed that salt and sugar were completely solubilized. Although biochemical oxygen demand ( < 0.3 mg L-1) and chemical oxygen demand ( < 5 mg L-1) were extremely low, the resident microbial communities remained electroactive, indicating that the MFC could recover energy even from matrices with low biodegradability. Response surface methodology (RSM) based on a central composite design (CCD) was used to model and optimize the effects of pH, exposure time, and substrate concentration on conductivity, total dissolved solids, and oxidation--reduction potential. Strong quadratic and interaction effects (p < 0.0001) indicated nonlinear interactions between redox potential and ionic strength. These findings suggest that low-cost additive strategies may improve MFC performance in dilute effluents from the Vaal region and support decentralized wastewater-to-energy applications.
Copyright (c) 2026 Wato Nathan Fundji, Kitenge Marie Ngoie, Kabamba Arthur Makenda, John Kabuba https://creativecommons.org/licenses/by/4.0
The impact of cognitive and emotional factors on user experience in HCI
Section: ENGINEERING SECTION Categories: ENGINEERING Keywords: Human–Computer Interaction (HCI), User Experience (UX), Cognitive Factors, Emotional Design, Affective Computing Disciplines: computer science This paper discusses how cognitive and emotional factors affect user experience (UX) in human-computer interaction (HCI). It examines how users' cognitive processes, including perception, attention, memory and decision-making, interact with emotional reactions, including satisfaction, trust and engagement, to shape the quality of interaction. Drawing on principles from cognitive psychology and affective computing, the study shows that effective HCI design extends beyond functionality and efficiency to include emotional appeal and user satisfaction. The paper emphasises that reducing cognitive load, maintaining interface consistency and using intuitive visual cues improve understanding and task performance. At the same time, integrating affective design principles, including aesthetic appeal, empathy and personalisation, contributes to greater emotional satisfaction and user motivation. It also assesses approaches for measuring UX, including usability testing, heuristic evaluation, affective feedback and physiological emotion monitoring, to capture the cognitive and emotional dimensions of interaction. The findings indicate that combining cognitive ergonomics and emotional intelligence in interface design can produce more adaptive, engaging and human-centred systems. By balancing mental efficiency with positive emotional experience, designers can create technologies that promote trust, empathy and long-term user engagement. Overall, this study supports the value of balancing rational and affective design to develop interactive systems that are useful, efficient, meaningful and emotionally satisfying.
Copyright (c) 2026 Ike Joseph Mgbeafulike, Ogochukwu C. Okeke, Osita Miracle Nwakeze, Anthony T. Umerah, Uju Cynthia Nwabudike, Chikaodili Chidi-Onuigbo https://creativecommons.org/licenses/by/4.0
High-performance and economically viable La2NiMnO6-based carrier transport layer-free perovskite solar cell with carbon-contact feasibility: a SCAPS-1D analysis
Section: PHYSICS SECTION Categories: PHYSICS Keywords: Perovskite solar cells, La2NiMnO6, Carrier transport layer-free, SCAPS-1D, Carbon contact. Disciplines: Physics, Computational Physics, Renewable Energy, Perovskite solar cels Carrier transport layers (CTLs) play a crucial role in conventional perovskite solar cells (PSCs) by aiding charge extraction. However, their involvement increases fabrication complexity, production cost, and potential instability. In this work, a simplified and economically viable CTL-free PSC configuration of FTO/La2NiMnO6/Au is proposed and systematically investigated using SCAPS-1D numerical simulation. Lanthanum nickel manganese oxide (La2NiMnO6) perovskite, an ambipolar absorber, is demonstrated to effectively perform both light absorption and charge transport without the need for auxiliary transport materials. Through systematic optimization of absorber thickness, defect density, electron capture cross-section, and resistive losses, a high power conversion efficiency (PCE) of 30.58% is recorded under standard illumination conditions, significantly outperforming previously reported single-absorber La2NiMnO6-based devices. The optimized device demonstrates strong defect tolerance, excellent carrier mobility balance, and robust thermal stability. Moreover, replacing the Au back contact with carbon (FTO/La2NiMnO6/C) yields a comparable PCE of 30.34%, confirming the potential for low-cost and scalable device fabrication. These results highlight the feasibility of eliminating CTLs in appropriately engineered devices and establish La2NiMnO6 as a promising material for next-generation, structure-simplified, and high-efficiency photovoltaic technologies.
Copyright (c) 2026 Peverga Rex Jubu, Akache Nathan-Abutu, Francis Aungwa, Chijioke Amakom, Izuchukwu Kenneth Nwokolo, Aaron Opeyemi Aransiola, Kufre I. Udofia, John Ojinere Anyanwu, Dehiin Donald Hile, Madan Mohan Gururani, Dooshima Judith Mtsor, Emeka Emmanuel Oguzie https://creativecommons.org/licenses/by/4.0
Using resistivity surveying methods for geotechnical study of subsurface properties for foundation design
Section: PHYSICS SECTION Categories: PHYSICS Keywords: Subsurface features, Foundation stability, Geotechnical evaluation, Electrical resistivity Disciplines: Physical Sciences The evaluation of subsurface properties plays a pivotal role in understanding geological formations and assessing their suitability for various engineering and environmental applications. In this work, the subsurface properties of open ground were investigated. Two constant separation traversing (CST) profiles were measured using the Wenner array electrode configuration, with electrode positions ranging from 0 to 150 m depending on the profile, and ten vertical electrical soundings (VESs) were conducted using the Schlumberger array electrode configuration, with half-current electrode separation (AB/2) ranging from 1 to 55 m. The topsoil resistivity ranged from 186.9 to 1222.0 Ω m, with an average of 422.5 Ω m, and its thickness ranged from 0.5 to 1.0 m. The weathered layer showed resistivity values between 13.6 and 70.0 Ω m, with a mean of 29.6 Ω m, thicknesses between 1.4 and 9.9 m, and depths between 1.9 and 10.9 m. These variations in resistivity and layer thickness indicate the presence of weathered and fractured zones that must be taken into account during foundation design.
Copyright (c) 2026 Adetoyinbo Adedeji Adegoke, Bello Adekunle Kazeem, Ogunseye Titus Taofik, Egbeyale Babatunde Godwin, Surajudeen Hadi Ademola, Adeleke Ayinla Ayooluwa https://creativecommons.org/licenses/by/4.0
Spectrophotometric and voltammetric assessment of totalflavonoid and phenolic content of Cucurbita species and theirantioxidant activity
Section: CHEMISTRY SECTION Categories: CHEMISTRY Keywords: Antioxidants, Voltammetry, Spectroscopy, Cucurbita Disciplines: Phyiscal Chemistry, Analytical Chemistry Evaluating the antioxidant properties of edible fruits is central to understanding their potential health benefits. We determined the antioxidant capacity and total phenolic and flavonoid contents of Cucurbita pepo and Cucurbita moschata using cyclic voltammetry and spectrophotometric assays, including 2,2'-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant potential (FRAP). A microwave-assisted method was used for extraction with n-hexane and methanol as solvents. The methanolic extracts produced higher phenolic contents in C. pepo (122.40 μg gallic acid equivalent (GA Eq)/mg) and C. moschata (132.4 μg GA Eq/mg) than the n-hexane extracts. Higher flavonoid levels were found in the methanolic extract of C. pepo (266.7 μg Q Eq/mg) and the n-hexane extract of C. moschata (177 μg Q Eq/mg). The DPPH assay showed higher percentage inhibition of free radicals in the n-hexane extracts of C. pepo (66.732 ± 6.976%) and C. moschata (58.425 ± 5.340%) than in the methanolic extracts. The FRAP assay indicated that the n-hexane extract of C. pepo had higher reducing power (∼98.0%) than the methanolic extract (∼77.5%), whereas the methanolic extract of C. moschata had higher reducing potential (∼106.9%) than the n-hexane extract (∼86.2%). The voltammetric assay showed that C. moschata had higher antioxidant activity (1.13 ± 0.061 μg GA Eq/mg and 4.19 ± 0.10 μg ascorbic acid equivalent (AA Eq)/mg) than C. pepo extracts (0.65 ± 0.004 μg GA Eq/mg and 3.40 ± 0.0068 μg AA Eq/mg). These findings provide insight into the antioxidant potential of two Cucurbita species and may support broader antioxidant research in food science and technology.
Copyright (c) 2026 C. Andrew, S. W. Ngbo, L. O. Edmund, P. S. Moses, P. Y. Olekwu, A. I. Onen https://creativecommons.org/licenses/by/4.0
Geophysical investigation of groundwater potential in parts of Afao Ekiti, Southwestern Nigeria
Section: GEOSCIENCES SECTION Categories: GEO SCIENCES Keywords: Aquifers, Fractured Basement, Groundwater Potential, Vertical electrical sounding, Water table Disciplines: Applied Geophysics A geophysical investigation was conducted to evaluate groundwater potential and explain anomalous water-table behaviour in hand-dug wells in a new community at Afao Ekiti during the 2023--2024 dry and wet seasons. The study used water-table measurements from ten observatory wells and Vertical Electrical Soundings (VES) data acquired along five traverses with the Schlumberger array. Electrode spacing (AB/2) varied from 1 to 100 m, and the maximum surveyed length was 200 m. Water tables were higher during the dry season than during the rainy season in eight wells, while two wells remained dry in both seasons. The interpreted VES results divided the area into two zones and revealed four lithologic units: topsoil, lateritic layer, weathered layer, and fractured or fresh basement. Two aquifer types were identified: a weathered-basement unconfined aquifer with resistivity values ranging between 50--150 Ωm. and a fractured-basement confined aquifer with resistivity values ranged between 100--250 Ωm. Groundwater potential is higher in Zone 1 than in Zone 2. Boreholes sited within Zone 1 are therefore expected to be productive and to yield groundwater sufficient for community needs.
Copyright (c) 2026 Oladunjoye Peter Olabode, Tokunbo Sanmi Fagbemigun, John Oluwabemiwo Olaleye, Oluwaseyi Elijah Ayobami, Tamarantare Favour Preh, Oluwatimilehin Moses Fadare https://creativecommons.org/licenses/by/4.0
Computational method for Volterra integro-differential equations of the second kind
Section: SPECIAL ISSUE IN HONOUR OF PROF. OLABODE MATTHIAS BAMIGBOLA Categories: MATHEMATICAL SCIENCES Keywords: Volterra integro-differential equations, Interpolation technique, Stability analysis, Collocation technique Disciplines: Computational and Applied Mathematics This study presents a computational method (CM) for solving second-kind Volterra integro-differential equations (VIDEs), which are widely used in engineering, physics, biology, and control systems. The method combines interpolation and collocation techniques to produce a continuous one-step computational scheme that accurately approximates the solution while maintaining stability and convergence properties. Consistency, zero-stability, order of accuracy, convergence, and the region of absolute stability are examined to confirm the suitability of the method for both linear and nonlinear problems. Numerical experiments with selected VIDEs compare the CM with the fifth--order Adams–Bashforth–Moulton predictor--corrector method, the two-point three-step block method, the trigonometrically fitted block method, the Haar wavelet method, and trapezoidal schemes. Across the tested examples, the CM provides accurate, stable, and efficient approximations, making it a useful tool for solving complex integro-differential systems in practical applications.
SPECIAL ISSUE IN HONOUR OF PROF. OLABODE MATTHIAS BAMIGBOLA
Copyright (c) 2026 Abdullahi Muhammed Ayinde, Adam Ajimoti Ishaq, Lukman Olalekan Ahmed, Emmanuel Jacob https://creativecommons.org/licenses/by/4.0
Transmission dynamics of community-and hospital-acquired infections: insights from mathematical modelling
Section: SPECIAL ISSUE IN HONOUR OF PROF. OLABODE MATTHIAS BAMIGBOLA Categories: MATHEMATICAL SCIENCES Keywords: Community transmission, local and global stability, bifurcation analysis, hospital-acquired infection Disciplines: Mathematical epidemiology Hospital-associated infections (HAIs) remain a critical public health challenge, particularly in resource-limited settings where surveillance and infection control are inadequate. This study develops and analyzes a modified S E I R mathematical model, denoted by S EcIcEhIhR, to capture the transmission dynamics of infectious diseases across hospital and community settings. The model incorporates both community and hospital transmission of infections, which have not been addressed jointly in previous studies. Using the next-generation matrix approach, the basic reproduction number (R0) was determined. Local and global stability analyses revealed that the disease-free equilibrium is stable when R0 < 1, but unstable otherwise. Sensitivity analysis identified the recruitment rate, community contact rate, and hospital infection rate as the most influential parameters, with community transmission exerting a stronger impact on the overall dynamics than hospital transmission. Numerical simulations further confirmed the dominant role of community transmission over hospital infections. Bifurcation analysis confirmed the possibility of backward bifurcation, indicating the possible coexistence of endemic and disease-free equilibrium states, even when R0 < 1. These findings highlight the complex interplay between hospital and community transmission and indicate that effective control strategies must prioritize reducing community contact rates while strengthening hospital infection-prevention measures. The model provides insights for policymakers and healthcare managers designing evidence-based interventions to mitigate HAIs and community outbreaks, particularly in countries facing systemic healthcare challenges.
Copyright (c) 2026 Peace P. Desben, Emmanuel N. Dashe, Joel N. Ndam https://creativecommons.org/licenses/by/4.0
Towards strengthening edge computing security through stack protection mechanisms
Section: MATHEMATICAL SCIENCES SECTION Categories: MATHEMATICAL SCIENCES Keywords: Agricultural Internet of Things, Stack protection, ARM Cortex-M4, Attack prevention Disciplines: Software engineering, Cybersecurity, anomaly detection, smart home, IoT, Information Systems, Machine Learning, Artificial intelligence, Computer Networks Stack-based attacks pose a major security risk to lightweight edge computing devices used in smart agriculture. This study investigated a secure stack-protection model for Advanced RISC Machines (ARM) Cortex-M4 microcontrollers commonly used in agricultural Internet of Things (IoT) workloads in Nigeria. Six configurations were simulated: Memory Protection Unit (MPU), Stack Canary, Shadow Stack under Mask (SuM), Control-Flow Integrity (CFI), a Hybrid MPU--SuM mechanism, and an unprotected control. The Python-based simulation modelled 500 sensor readings and 100 simulated attack attempts for each mechanism. The Hybrid mechanism prevented all simulated attacks within the defined threat model while incurring only 2.90% performance overhead and a 2.83% reduction in estimated battery life. It maintained an operational lifetime above 5.8 months on a 2000 mAh battery. Although CFI also achieved complete prevention in the simulation, its 10.00% overhead reduced its suitability for latency-sensitive and duty-cycled sensor workloads. The results indicate that hardware-assisted protection, particularly MPU enforcement and the Hybrid MPU--SuM approach, can provide practical stack-level security for resource-constrained agricultural IoT nodes without requiring additional hardware.
Cybersecurity, anomaly detection, smart home, IoT
Information Systems, Machine Learning, Artificial intelligence
Copyright (c) 2026 Justine Utsu Undiandeye, Moses Adah Agana https://creativecommons.org/licenses/by/4.0
A culturally aware NLP approach for fake-news detection in Nigerian online media using BERT
Section: MATHEMATICAL SCIENCES SECTION Categories: MATHEMATICAL SCIENCES Keywords: BERT, Fake-news detection, Nigerian media, Multilingual natural language processing Disciplines: computer science Fake-news dissemination in multilingual Nigerian media poses serious sociopolitical risks, yet many existing detection models do not adequately account for Nigeria's linguistic and cultural diversity. This study presents a culturally aware natural language processing (NLP) model for fake-news detection based on the Bidirectional Encoder Representations from Transformers (BERT) architecture. A curated corpus of 10,000 Nigerian news articles was assembled and stratified across Standard English, Nigerian Pidgin, Yoruba, Hausa, and Igbo. The model combines language-adaptive fine-tuning with regulatory-informed annotation based on the standards of the National Broadcasting Commission (NBC), Nigerian Communications Commission (NCC), and National Information Technology Development Agency (NITDA). Experimental results show that the proposed model achieved 91.3% accuracy, 90.8% precision, and an 89.7% F1-score, outperforming vanilla multilingual BERT and traditional machine-learning baselines. The system also performed strongly on indigenous-language and code-switched content, with an average inference latency below 400 ms. The study provides a scalable and context-dependent decision-support model for real-time misinformation detection in the Nigerian online-media environment.
Multilingual natural language processing
Copyright (c) 2026 Mutiat A. Ogunrinde, Yusuf B. Yusuf https://creativecommons.org/licenses/by/4.0
Rain fade impairment analysis for Earth-to-space radio links using site diversity techniques in Delta State, Nigeria
Section: PHYSICS SECTION Categories: PHYSICS Keywords: Rain attenuation, Site diversity, Earth-to-space link, Ku-band, Satellite communication Disciplines: Physics Electronics Site diversity is a fade mitigation technique that employs two or more spatially separated receiving stations to reduce the adverse effects of rain attenuation on satellite communication links. Its effectiveness is particularly important in tropical regions where intense convective rainfall frequently degrades Earth-to-space radio communications. This study investigates rain fade impairment and evaluates the effectiveness of site diversity for Ku-band Earth-to-space radio links in Warri, Delta State, Nigeria, a tropical coastal environment with high rainfall intensity. Rain rate and received signal level measurements collected during the peak rainy months of 2024 were analysed to generate cumulative distribution functions (CDFs) for rainfall occurrence and attenuation statistics. The study adopted the ITU-R P.618-11 and P.618-12 propagation models to estimate rain attenuation and diversity gain for both single-site and joint-site configurations. Results show that rain attenuation increases with rainfall intensity and becomes particularly severe for rainfall rates exceeding 70 mm/h. Maximum single-site attenuation values of 54.83 dB and 25.12 dB were observed during rainfall intensities of 200 mm/h in July and August, respectively. The application of site diversity reduced attenuation significantly, producing maximum diversity gains of 13.76 dB, 5.27 dB, 5.22 dB, and 4.10 dB for July, April, August, and October, respectively. Negative diversity gains observed at low rainfall intensities indicate periods of high spatial correlation between rain cells, during which diversity effectiveness is reduced. The findings validate the applicability of the ITU-R site diversity model under tropical convective rainfall conditions and provide localized propagation information for the design and optimization of reliable Ku-band satellite communication systems in the Niger Delta region of Nigeria.
Copyright (c) 2026 Jangfa Timothy Zhimwang https://creativecommons.org/licenses/by/4.0
Proteomic characteristics of resistant Proteus species in women with urinary tract infections in Nasarawa State, Nigeria
Section: BIOLOGICAL SCIENCES SECTION Categories: BIOLOGICAL SCIENCES Keywords: Multidrug resistance, Virulence, Plasmids, Outer membrane proteins, Bacteriuria Disciplines: Microbiology Urinary tract infections (UTIs) represent a recurring clinical challenge, primarily due to escalating pathogen resistance. Although Proteus species are not the most commonly isolated pathogens in UTIs, they typically exhibit high levels of resistance when present. This study investigated the proteomic profiles of resistance and virulence determinants in Proteus species isolated from women with UTIs in Nasarawa State, Nigeria. Urine samples were collected from 368 patients, from which Proteus isolates were identified and evaluated for resistance and virulence factors. Proteomic characteristics were determined following growth in Luria–Bertani (LB) broth and artificial urine (AU). Ten Proteus isolates, comprising four P. vulgaris and six P. mirabilis, were obtained from 21 urine samples exhibiting significant bacteriuria. Both species were found to harbor adhesion (20 kb) and hemolysin (30 kb and 50 kb) plasmids. Identified resistance elements included an ESBL plasmid (40 kb and 80 kb), a conjugative R-plasmid (50 kb), and a multidrug conjugative plasmid (200 kb). The outer membrane vesicle (OMV) yield ranged from 89.5-137μg/mL for P. vulgaris and 97.6-140μg/mL for P. mirabilis. The OMVs exhibited a unimodal size distribution, with average diameters ranging from 70 nm to 180 nm. Recovered outer membrane-associated proteins included outer membrane protein A (OmpA), porins (OmpC and OmpF), flagellin structural proteins (FliC and FlgE), lipoproteins (Lpp and Pal), and proteases (DegP and HtrA). Notably, P. mirabilis cultured in AU was enriched with virulence-related proteins, such as urease subunits (UreA, UreB, and UreC) and fimbrial adhesion proteins. This study confirms the complex nature of virulence and resistance factors in Proteus species, which significantly contribute to treatment failure in patients. 0.45μm
Copyright (c) 2026 M. H. Muhammad, O. O. Orole, J. F. Nfongeh, E. S. Audu, F. Gbadeyan https://creativecommons.org/licenses/by/4.0
Perturbation and bifurcation analysis of a primary-secondary dengue infection transmission model with explicit vector dynamics and optimal control
Section: MATHEMATICAL SCIENCES SECTION Categories: HEALTH & MEDICAL SCIENCES Keywords: Dengue, bifurcation, Perturbation, Reproduction number, Sensitivity Disciplines: Mathematical Modelling A robust mathematical model of multi-strain dengue infection with explicit vector dynamics is formulated to incorporate optimal control and vaccination. The bifurcation coefficients were calculated, and their numerical perturbation led to transcritical, subcritical, and supercritical bifurcations. The results showed that the effective reproduction number of the model with control is sufficiently small compared with the basic reproduction number without control. The rate of secondary infection with control, ϕc, was also lower than the rate of secondary infection without control, ϕ0; that is, ϕc < ϕ0. The sensitivity results showed that the mosquito-to-human and human-to-mosquito interaction rates should be targeted by control interventions to reduce infection in the population.
Copyright (c) 2026 Aloysius N. Ezaka, Henry O. Adagba, Sunday N. Aloke, Louis O. Omenyi, Theresa E. Efor, Okorie Nwite, Chika Agha https://creativecommons.org/licenses/by/4.0
Measurement and characterization of ambient air pollutants in selected industrial areas of Kaduna, Nigeria
Section: PHYSICS SECTION Categories: PHYSICS Keywords: Air pollution, Particulate matter, Gaseous pollutants, WHO standards, Kaduna State Disciplines: Environmental Sciences Air pollution from industrial sources is a critical environmental and public health concern in Nigeria. This study measured concentrations of gaseous pollutants (CO, NO, NO2, SO2, H2S, NH3) and particulate matter (PM1.0, PM2.5, PM10) in selected industrial areas of Kaduna Metropolis, Northwestern Nigeria. Five major stationary emission sources Kaduna Refinery, Indomie Factory, Hikman Gas Plant, PZ Cusson Factory, and A.A. Rano Diesel Plant were sampled at distances of 10--100 m from emission points. Results showed that pollutant concentrations decreased exponentially with distance due to atmospheric dispersion. Comparisons with WHO 24-hour guideline limits(CO: 4.00 μg/m3; PM2.5: 5.00 μg/m3; PM10: 20.00 μg/m3) revealed significant exceedances at four functional sites. At Indomie Factory, CO (18.71 μg/m3) and PM2.5 (32.95 μg/m3) exceeded limits by factors of 4.7 and 6.6. At Hikman Gas Plant, CO (15.30 μg/m3) and PM2.5 (24.55 μg/m3) exceeded limits by factors of 3.8 and 4.9. At PZ Cusson Factory, CO (16.18 μg/m3) and PM2.5 (32.45 μg/m3) exceeded limits by factors of 4.0 and 6.5. At A.A. Rano Diesel Plant,(17.96 μg/m3) and PM2.5 (27.89 μg/m3) exceeded limits by factors of 4.5 and 5.6. PM10 at Indomie Factory (60.07 μg/m3) exceeded the WHO limit by a factor of 3. The non-operational Kaduna Refinery recorded values within permissible limits. Diesel generator exhaust was identified as the major contributor (CO--PM2.5: r = 0.82, p < 0.01). The study recommends routine monitoring, cleaner energy adoption, and stricter enforcement of air quality standards.
Copyright (c) 2026 J. Lawal, A. A. Tyovenda, H. Lawal, M. U. Sarki, J. A. Lawal, D. A. Ismaila, D. S. Igba https://creativecommons.org/licenses/by/4.0
Fractional nonlocal strain-gradient isogeometric analysis of porous functionally graded piezoelectric microplates resting on elastic substrates
Section: MATHEMATICAL SCIENCES SECTION Categories: MATHEMATICAL SCIENCES Keywords: Fractional nonlocal strain–gradient, Porous piezoelectric microplates, Isogeometric analysis, Elastic substrate interaction Disciplines: Applied mathematics, Structural dynamics, and Computational modeling Existing strain-gradient models for piezoelectric microplates often capture local microstructural size effects but do not simultaneously represent long-range spatial interactions, porosity-induced material degradation, electromechanical coupling, and elastic-substrate effects within a unified computational framework. This paper develops a fractional nonlocal strain-gradient isogeometric formulation for the free vibration analysis of porous functionally graded piezoelectric microplates resting on elastic substrates. The plate kinematics are described using higher-order shear deformation theory, while the fractional Laplacian operator is introduced to model spatial nonlocality and the strain-gradient term accounts for intrinsic length-scale stiffening. The governing equations are derived from Hamilton's variational principle by incorporating thickness-dependent elastic, piezoelectric, dielectric, and density properties. The Winkler-Pasternak foundation model is used to represent substrate interaction, and isogeometric analysis is adopted to satisfy the higher-order continuity requirements of the enriched formulation. The proposed model is validated against published benchmark results in the classical and strain-gradient limits, with percentage-error comparisons included. Parametric results show that porosity reduces the natural frequencies, whereas strain-gradient effects and elastic foundation stiffness increase them. The fractional order, nonlocal interaction length, applied electric voltage, and porosity pattern significantly influence the effective stiffness and vibration response. The proposed formulation provides a physically consistent framework for designing smart porous piezoelectric microplates used in microelectromechanical systems, sensors, actuators, and micro-energy harvesting systems.
Applied mathematics, Structural dynamics, and Computational modeling
Copyright (c) 2026 Sule Adekunle Jimoh, Olorunsola Oriola Niyi, Adebola Samuel Adeoye, Daramola Oluwatosin Bunmi, Ezekiel Olaoluwa Omole https://creativecommons.org/licenses/by/4.0
Comparative effects of resistance training and aerobic exercise on ovulation and female reproductive physiology
Section: HEALTH & MEDICAL SCIENCES SECTION Categories: HEALTH & MEDICAL SCIENCES Keywords: Resistance training, Aerobic exercise, Ovulation, Reproductive health, Exercise physiology Disciplines: Physical Education Physical exercise plays an important role in reproductive health, particularly through its influence on the hypothalamic--pituitary--ovarian (HPO) axis and ovulation. Although both resistance training (RT) and aerobic exercise (AE) benefit women's health, their comparative effects on ovulatory function remain unclear. This narrative review evaluates the differential effects of RT and AE on ovulatory function from a sports physiology perspective, with emphasis on training type, intensity, and frequency. Literature was identified through major scientific databases, including PubMed, Scopus, Web of Science, and Google Scholar, with a focus on exercise and female reproductive health. The evidence suggests that RT and AE may have beneficial but distinct effects on ovulatory function mediated by metabolic and hormonal mechanisms. Moderate- to high-intensity AE has been reported to improve body mass index (BMI), insulin sensitivity, and menstrual regularity, whereas RT may support muscle development, androgen regulation, and metabolic health. However, excessive exercise or insufficient energy intake can disrupt gonadotropin-releasing hormone (GnRH) pulsatility and suppress gonadotropins, which may lead to menstrual dysfunction. Overall, AE has more consistent evidence for improvements in BMI and menstrual-cycle regularity, while RT shows promising but still emerging benefits for androgen regulation and metabolic health. These findings may guide women, healthcare providers, and policymakers in tailoring exercise choices to protect women's ovulatory and reproductive health. Future studies should prioritise comparative exercise trials, diverse populations, and the incorporation of nutritional factors.
Copyright (c) 2026 Olajumoke Oyedoyin https://creativecommons.org/licenses/by/4.0
Environmental exposure and health risk assessment of particulate-associated heavy metals from medical waste incineration
Section: PHYSICS SECTION Categories: PHYSICS Keywords: Particulate-associated heavy metals, Medical waste incineration, Environmental exposure, FAAS Disciplines: Radiation and Health Physics, Environmental management and toxicology Incineration, a widely adopted waste-management strategy, poses significant health and environmental risks because of the continuous emission of heavy metals (HMs). In this study, the levels of ten HMs (Zn, Fe, Cu, Cr, Cd, As, Ni, Co, Pb, and Hg) were determined in particulate matter around a hospital incineration facility using flame atomic absorption spectrometry (FAAS). HM concentrations ranged from 0.059 to 0.330 mg kg-1 in the descending order Zn > Fe > Cu > Cr > Cd > As > Ni > Co > Pb > Hg. Statistical analysis confirmed significant differences between the exposed sites and the control baseline (p < 0.05). The mean levels of Ni, As, Cd, Hg, Pb, and Cr (0.120, 0.1216, 0.1440, 0.0592, 0.0704, and 0.2192 mg kg-1, respectively) exceeded World Health Organization limits, indicating potential ecological and public health risks. Strong positive correlations (p < 0.01) were obtained between specific metal pairs (As--Pb: r = 0.864; Hg--Cd: r = 0.517; Ni--Pb: r = 0.670; Pb--Cr: r = 0.983), suggesting common emission sources and synergistic environmental effects. Several other metals also exhibited strong positive correlations, including Cr--Co, Cr--Pb, Cd--Ni, As--Ni, Cu--Co, and Pb--Co (r > 0.70). These associations reiterate multiple common exposure pathways among workers occupationally exposed to the hospital incinerator. These findings highlight the need for enhanced regulatory frameworks and mitigation strategies to address pollution, safeguard public health, and promote sustainable waste management in this environment.
Copyright (c) 2026 O. O. Oketayo, E. E. Osara, A. E. Odo, O. P. Idowu, O. J. Oluwadare, M. M. Orosun https://creativecommons.org/licenses/by/4.0
Evaluation of some Bayesian parametric survival models with application to hypertensive patients
Section: MATHEMATICAL SCIENCES SECTION Categories: HEALTH & MEDICAL SCIENCES, MATHEMATICAL SCIENCES Keywords: Parametric models, Survival, Bayesian approach, Proportional hazards, Hypertension Disciplines: Applied statistics, Public health sciences Bayesian parametric survival models provide a flexible framework for time-to-event analysis, particularly when structural assumptions may enhance efficiency. However, performance in low-event settings remains an important practical consideration. We evaluated three Bayesian parametric survival models: Exponential, Weibull, and Lognormal, using data from 155 hypertensive patients, among whom 14 events (9.1%) were observed. Five clinically relevant covariates were included a priori in all models. Posterior inference was obtained via Markov Chain Monte Carlo methods. Model comparison was performed using WAIC (Watanabe-Akaike Information Criterion) and LOOIC (Leave-one-out cross-validation). Sensitivity analyses were conducted under alternative prior specifications to assess robustness. The Bayesian Lognormal model (SE = 50.5, LOOIC = 220.4, WAIC = 220.0) outperformed other models. The study showed that occupation is significantly associated with survival time of hypertension patients across all the models. These findings underscore the need for careful consideration of the choice of the parametric model to employ in survival data analysis. The results also suggest the need for the provision of job-related intervention in people's health regarding hypertension.
Copyright (c) 2026 Dorcas Modupe Okewole, Sunday Samuel Odebode, Olumide Sunday Adesina, Adedayo Funmi Adedotun https://creativecommons.org/licenses/by/4.0
Investigating chaos in solar activity over six solar cycles
Section: PHYSICS SECTION Categories: PHYSICS Keywords: Solar cycle, Sunspot number, Equivalent planetary amplitude, Solar radio flux, Chaos Disciplines: Theoretical Physics, Ionospheric & Space Weather Research In this work, nonlinear dynamical characterization of selected geospace variables was undertaken by analyzing temporal chaotic trends in daily sunspot number (SSN), equivalent planetary amplitude (Ap), and solar radio flux (F10.7obs) data over six solar cycles (19--24). The nonlinear analysis tools used were correlation dimension, Lyapunov exponents, approximate entropy, and the Gottwald--Melbourne 0--1 test. The results show that the Lyapunov exponents, correlation dimension, and 0--1 test values indicate the presence of low-dimensional deterministic chaos in SSN, Ap, and F10.7obs. The Lyapunov exponent values were positive, the correlation dimension values fell within the range 2.1 < D2 < 2.3, the surrogate significance test returned positive values for all three parameters, and the 0--1 test results were very close to one (all >0.99). The Hurst values were between 0.8 and 1, indicating persistence and long-term autocorrelation. Based on the correlation dimension and Lyapunov exponent values, the chaoticity was affirmed as Ap < SSN < F10.7obs. Chaotic trends across the solar cycles showed that the degree of chaos in all three solar-cycle parameters increased from cycle 19 to cycle 24. This increase is attributed to small perturbations in interior plasma flow, shear in the axis of rotation, and variation in the strength and orientation of the Sun's geomagnetism, which are amplified over time, as evident in the decrease in the mean SSN (129--49) and increase in the signal-to-noise ratio (0.84--0.96). These processes lead to increased fluctuations in the amplitude and periodicity of solar activity from one solar cycle to another.
Copyright (c) 2026 Grace Adagba, Emmanuel Vezua Tikyaa, Tertsea Igbawua, Moses Owoicho Audu https://creativecommons.org/licenses/by/4.0
Knowledge, attitudes, and cervical cancer screening practices among HIV-positive female sex workers in Benue State, Nigeria
Section: HEALTH & MEDICAL SCIENCES SECTION Categories: HEALTH & MEDICAL SCIENCES Keywords: Cervical cancer screening, Female sex workers, HIV, Attitude Disciplines: Public Health Cervical cancer is a leading cause of cancer-related deaths in sub-Saharan Africa, and women with human immunodeficiency virus (HIV) are at significantly increased risk. However, information on cervical cancer screening among female sex workers (FSWs) in parts of Nigeria remains limited. This study assessed knowledge, attitudes, and screening practices relating to cervical cancer among HIV-positive FSWs in Benue State, Nigeria, and examined variables associated with screening behaviour. A facility-based descriptive cross sectional study was conducted among 215 HIV-positive FSWs receiving care at Key Population One-Stop Shop (KP-OSS) facilities in Makurdi, Gboko, and Otukpo. Data were collected using interviewer-administered questionnaires. The mean age of the participants was 32.1 ± 6.7 years, and 74.6% lived in urban areas. Overall, 77.2% had previously undergone cervical cancer screening, most commonly by visual inspection with acetic acid (VIA). In addition, 76.9% understood how cervical cancer could be prevented, whereas 66.5% demonstrated general awareness of the disease. Nevertheless, fear of the screening procedure (44.2%), fear of a positive diagnosis (49.8%), and embarrassment about genital exposure (42.3%) were reported. Knowledge was not a significant predictor of screening behaviour (β = 0.002, p > 0.05), whereas attitude was significant (β = −0.32, p < 0.01). Screening behaviour was negatively correlated with age and number of pregnancies (p < 0.01). Negative attitudes and psychosocial barriers persisted and significantly influenced screening behaviour. Culturally tailored behavioural interventions and psychosocial support should therefore be integrated into HIV care platforms to enhance cervical cancer screening uptake in this high-risk population.
Copyright (c) 2026 G. E. Ameh, L. Ameh, A. M. Ogbode, S. U. Adamu, F. O. Ejembi https://creativecommons.org/licenses/by/4.0