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Impact of nano-Al 2 O 3 particle size on shear bond strength in petroleum and low-temperature geothermal wells
(Elsevier Ltd., 2026-08-04) Maagi, Mtaki
This study examines the shear bond strength of cement paste at the wellbore interface in petroleum and low-temperature geothermal wells. Class G cement enhanced with nano-Al2O3 (NA) particles (20 nm and 40 nm) was used for wellbore simulations at 80°C. The particles were chosen in percentages of 1, 2, 3, and 4% based on the weight of cement. According to the research results, the interfacial shear bond strength was considerably increased by NA. The findings also demonstrated that the size of the NA particles influenced the strength improvement. The specimens with NA 40 nm offered more strength than those with 20 nm due to their notable pozzolanic effects. By adjusting the NA doses, the optimal replacement content was found to be 3% across all sizes of particles. The size of the particles solely affected the interface bonding strength, it did not affect the ideal dosing of NA. By incorporating 3% (40 nm) NA, the strength improved by 557.14, 525.00, 514.75, and 421.30% at 3, 7, 14, and 28 days, respectively. Overall, NA boosts shear bond strength through microstructure refinement. Its smaller dimensions provide multiple benefits to improve well integrity for prolonged zonal isolation. The effect of NA on cement-formation bond was investigated using a scanning electron microscope, X-ray diffraction, and thermogravimetric method.
Waste-derived activated carbon electrodes from Colocasia esculenta peels for lead removal using flow-electrode capacitive deionization
(Elsevier Ltd., 2026-08-18) William, Erick; Jande, Yusufu; Alfredy, Tusekile
Transforming agricultural waste into high-value water treatment materials offers a sustainable solution to pollution and resource scarcity. However, biomass-derived carbon electrodes with optimized hierarchical porosity and surface chemistry for efficient Pb2+ electrosorption in flow-electrode capacitive deionization (FCDI) remain underexplored. In this study, activated carbon derived from Colocasia esculenta peels (CEPAC) was investigated as a sustainable flow-electrode material for Pb2+ removal. CEPAC was synthesized through carbonization, followed by KOH activation at mass ratios of 1:1–1:4. The optimized activated sample (CEP-1:2.0) exhibited a well-developed porosity with a high specific surface area of 1364.39 m2 g−1 compared to CEP (379.91 m² g⁻¹), abundant oxygen-containing functional groups, and improved hydrophilicity. Electrochemical testing confirmed superior capacitive behavior, with a maximum CV specific capacitance of 384.53 F g⁻¹ at 1 mV s−1. Under optimal FCDI operating conditions (1.2 V, 2.5 wt% slurry concentration, and 100 mg L−1 initial Pb2+), the CEP-1:2.0 electrode achieved a Pb²⁺ removal efficiency (RE) of 90.1 ± 1.8% and a lead electrosorption capacity (LEC) of 3.5 ± 0.04 mg g⁻¹, outperforming pristine CEP (42 ± 2.8% RE, 1.7 ± 0.06 mg g−1). These findings underscore the potential of CEPAC, particularly at a 1:2 activation ratio, as a cost-effective, improved-performance electrode for scalable heavy-metal remediation, especially Pb2+.
Improving functional properties of maize bran by lactic acid bacteria fermentation: Insights from physicochemical properties, amino acid composition, aroma profile, antioxidant activities, and metabolomics analyses
(Elsevier Ltd., 2026-10-15) Dimoso, Noel; Chen, Caowei; Tang, Anqi; Feng, Yue; Yang, Zhen-Quan
Maize bran (MB), a nutrient-rich milling by-product, was separately solid-state fermented by Limosilactobacillus fermentum, Lactiplantibacillus plantarum, and Pediococcus pentosaceus strains. Subsequently, their effects on the structural properties, bioactivity, and chemical composition of MB were investigated. Compared to the others, L. fermentum rapidly promoted acidification of MB with the relative content of volatile 3-methylpentanoic acid reaching 32.92% after 24 h and significantly enhanced the hydroxyl radical scavenging rate by 58.92% after 48 h. L. plantarum fermentation exhibited an excellent water solubility index (33.33%), swelling capacity (254%), total phenolics (3.95 mg gallic acid equivalent (GAE)/g), and ABTS•+ scavenging rate (90.45%) and had high relative contents of volatile 3-furaldehyde and vanillin at 16.06% and 2.14%, respectively, after 48 h. Notably, all strains significantly increased the contents of essential and branched-chain amino acids at 48 h and 72 h. Meanwhile, MB treated with P. pentosaceus for 72 h, with high contents of sweet (1125.33 mg/kg) and hydrophobic amino acids (1609.8 mg/kg), total phenolics (4.01 mg GAE/g), and volatile 2-furanmethanol (8.16%), exhibited a strong DPPH• scavenging rate (74.49%) and water absorption index (42.21%). Non-targeted metabolomics analysis revealed significant metabolic modulation, predominantly including amino acids, saccharides, fatty acids, benzoic acids, hydroxycinnamic acids, and their derivatives. Furthermore, L. plantarum, L. fermentum, and P. pentosaceus significantly enriched cofactor biosynthesis, pyrimidine metabolism, and phenylpropanoid biosynthesis, respectively. This study highlights the potential of fermented MB as a functional ingredient with food and nutraceutical value.
Structural drivers of per- and polyfluoroalkyl substances environmental fate, bioaccumulation kinetics, and sub-cellular toxicity: A systematic review of legacy and emerging alternatives
(Elsevier Ltd., 2026-10-15) Yeboah, Cornelius; Sackey, Lyndon; Asamoah, Daniel; Aidoo, Isaac; Mwema, Mwema
Per- and polyfluoroalkyl substances (PFAS) pose a critical global challenge due to extreme persistence and multi-media migration. Following PRISMA 2020 guidelines, this systematic review synthesized data from 22 core studies to evaluate environmental fate, bioaccumulation, and sub-cellular toxicity using an adapted Joanna Briggs Institute appraisal. The findings revealed a structural division: hydrophobic long-chain compounds (PFOS, PFOA, PFNA) and chlorinated substitutes (8:2 Cl-PFESA) sequestered in solid repositories, exhibiting sediment-water partition coefficients (logKd) from 1.64 to 4.14 with a direct linear increase (R2=0.99) per carbon atom. Soluble short-chain variants (PFBA, PFBS) and ether substitutes (GenX) tracked with stormwater and translocated into edible foliage. In aquatic webs, linear PFOS showed extreme biomagnification in apex predators (Trophic Magnification Factors 3.7–9.3), accelerated by slow in-situ transformation of sediment SAmPAP precursor reservoirs. Epidemiological tracking indicated traditional water-based one-compartment toxicokinetic models systematically under-predicted real-world serum burdens (up to 116.2 μg/Lfor PFOA) in high-exposure cohorts by omitting multi-media pathways like topsoil dust and local produce ingestion. At the sub-cellular scale, in silico docking verified that short-chain alternatives like PFBS possessed high competitive binding affinities for fish estrogen receptors, triggering multi-generational reproductive failure, altered endocrine signaling, and disrupted adipocyte lipogenesis. While shortening fluorocarbon chains minimizes human serum accumulation, it heightens environmental mobility and introduces sub-cellular metabolic risks. Future research must resolve baseline data deficits across the Global South and adopt multi-media toxicokinetic frameworks to establish internationally standardized reference doses.
Computational elucidation of the potential mechanisms of Warburgia ugandensis against colorectal cancer
(Springer Nature, 2026-10-01) Amos, Yohana; Nsengimaana, Bienvenu; Faleyimu, Mercy; Adeniyi, Peter; Lawal, Aishat; Kenou, Orace; Martin, Darius; Jawali, Ashita; Awe, Olaitan
Background
Colorectal cancer remains a major global health challenge due to its high incidence, mortality, therapeutic resistance, and treatment-related adverse effects. Warburgia ugandensis is a medicinal plant that has demonstrated anti-colorectal cancer; however, the specific bioactive compounds responsible and their underlying molecular mechanisms remain underexplored. This study investigated the anti-colorectal cancer potential and molecular mechanisms of W. ugandensis phytochemicals using an integrated computational approach.
Methods
Phytochemicals were retrieved from published literature and the Collection of Open Natural Products database, standardized, and screened for drug-likeness and oral bioavailability. Potential protein targets were predicted and intersected with colorectal cancer-associated genes, followed by network pharmacology and functional enrichment analyses. Molecular docking, 100 ns molecular dynamics simulations, molecular mechanics Poisson-Boltzmann surface area binding energy calculations, and absorption, distribution, metabolism, excretion, and toxicity (ADMET) analyses were performed to evaluate compound-target interactions, complex stability, and pharmacological properties.
Results
Among 242 identified phytochemicals, 21 compounds satisfied drug-likeness and oral bioavailability criteria. Target prediction identified 435 potential protein targets of the screened phytochemicals, of which 411 overlapped with colorectal cancer-associated genes. Network analysis of the overlapping targets identified PIK3CA, PIK3CD, GNAI1, GNAI3, and SRC as key hub genes. Functional enrichment analysis suggested that these targets are involved in cancer-relevant signaling pathways, including the phosphatidylinositol 3-kinase-protein kinase B, insulin receptor, and relaxin signaling pathways. Molecular docking identified quercetin, kaempferol, and bemadienolide as leading candidates, with strong binding affinities toward GNAI1 (-9.8 kcal/mol), GNAI3 (-9.6 kcal/mol), and PIK3CD (-8.7 kcal/mol), respectively. Molecular dynamics simulations demonstrated stable protein-ligand complexes with reduced structural fluctuations over 100 ns. Binding free energy analysis revealed favorable interactions, with quercetin-GNAI1 showing the strongest predicted binding stability (-86.2 ± 3.3 kcal/mol). Pharmacokinetic and toxicity predictions indicated high gastrointestinal absorption and generally low predicted toxicity profiles.
Conclusion
This study provides computational, hypothesis-generating evidence that Warburgia ugandensis phytochemicals may modulate multiple molecular targets and signaling pathways involved in colorectal cancer. Quercetin, kaempferol, and bemadienolide represent promising candidates for further experimental investigation. Nevertheless, these predictive findings require validation through in-vitro and in-vivo studies to establish their therapeutic relevance.