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Total synthesis of isoflavonoids
Selepe, Mamoalosi A.; Mthembu, Siyanda T.; Sonopo, Molahlehi S. (Royal Society of Chemistry, 2025-03)
Isoflavonoids are phenolic compounds with wide structural diversity and a plethora of biological activities. Owing to their structural variation and potential health-promoting and other benefits, they have been targeted for synthesis. Herein, we review the synthesis of natural isoflavonoids belonging to different classes that include isoflavones, isoflavanones, isoflavans, isoflavenes, pterocarpans, rotenoids, coumaronochromones, and coumestans. The synthetic methodologies employed and advancements in synthetic strategies are highlighted.
Editorial to the special issue on decoupling and environmental sustainability
Ryding, Daniella; Lichy, Jessica; Africa, South; Ritch, Elaine (Elsevier, 2026-02)
No abstract available.
Establishing linguistic categories for hearing aid experiences in adults : a modified Delphi study
Oosthuizen, Ilze; Manchaiah, Vinaya; Launer, Stefan; Swanepoel, De Wet (American Academy of Audiology, 2025-07)
BACKGROUND : Recent advancements in automated natural language processing (NLP) methods and tools have enhanced the efficacy and accuracy of quantitative analysis of natural language data. NLP offers significant potential for audiology by providing valuable insights from open-text responses about users’ lived hearing aid experiences. PURPOSE : This study aimed to establish linguistic categories pertinent to the experiences of adults using hearing aids, with the ultimate goal of developing a specialized text processing module to facilitate natural language analysis of textual data on hearing aid experiences. RESEARCH DESIGN : A modified electronic Delphi (e-Delphi) design was employed. STUDY SAMPLE : A panel of 16 audiology experts from seven countries. DATA COLLECTION AND ANALYSIS : Two survey rounds were conducted. In round 1, experts rated categories from the Linguistic Inquiry and Word Count (LIWC) software and categories from principal component analysis of open-ended text data on hearing aid experiences. Experts also responded to open-ended prompts regarding categories derived from qualitative studies on hearing aid experiences. Responses were condensed and refined into items for rating during round 2. In round 2, experts reconsidered their ratings in light of the group answers of round 1. All ratings used a four-point Likert scale of importance. Measures of central tendency, levels of dispersion, and Cronbach’s α reliability coefficients were conducted in both rounds for comparative purposes. RESULTS : The open-ended section generated 26 items. Consensus was met on 53 linguistic categories encompassing social (e.g., social situations, social support), emotional (e.g., positive tone, negative tone), cognitive (e.g., cognitive processes, causation), lifestyle (e.g., work, leisure), hearing aid–related (e.g., sound quality, use and handling), and service delivery–related dimensions. CONCLUSIONS : The linguistic categories identified provide a foundation for developing a customized LIWC text processing module tailored to the analysis of hearing aid experiences. Future research is needed to refine and validate the custom text processing module. CLINICAL RELEVANCE STATEMENT : The findings provide a framework to enable the development of a customized hearing aid LIWC dictionary. Such a tool may enhance clinicians’ ability to explore hearing aid outcomes and improve patient-centered care by integrating real-world experiences into clinical practice.
Increasing culvert hydraulic capacity for improved climate resilience : a physical modelling analysis
Giliomee, Maria Dorothea; Loots, Ione; Van Dijk, Marco (IWA, 2025-08)
Culverts often fail to handle increased flood peaks due to urbanisation and climate change. Modifying culvert inlets to increase discharge capacity can negate the need for additional culvert barrels or to rebuild the entire structure. Although some previous studies investigated hydraulic culvert improvements, this study is the first to test different combinations of headwall and wingwall angles, and the effect of aeration vents, to improve capacity of inlet-controlled culverts. This physical modelling study evaluates various modified box and circular culvert inlets, quantifies their impact on capacity, develops a coefficient for use in standard equations, and verifies the alignment of results with established references and guidelines. A 15° headwall with a 30° wingwall added to a box culvert or a rounded inlet edge for a circular culvert improved the flow by up to 34% at a headwater depth of twice the culvert height (2D), or up to 18% at 1.2D for box culverts and 24% at 1.2D for circular culverts. An air vent after the inlet had an insignificant influence on the capacity. A novel flow improvement coefficient was developed to calculate improved capacity with existing design equations. Culvert inlet improvements will reduce flood risks and contribute to sustainable drainage infrastructure.
Coal fly ash-based adsorbents for tetracycline removal : comparative insights into modification and zeolite conversion
Houghton, Eric Emmanuel; Yapi, Litha; Haneklaus, Nils; Brink, Hendrik Gideon; Tichapondwa, Shepherd Masimba (MDPI, 2025-03-01)
Emerging xenobiotics, such as tetracycline (TC), pose significant risks to both the environment and human health. Adsorption is a recognized method for removing these contaminants, and in this study, fly ash (FA), a by-product of coal combustion, was modified to develop adsorbents. Acid-modified FA (AM-FA) and base-modified FA (BM-FA) were prepared, and zeolite Na-P1 (ZNa-P1) was synthesized via hydrothermal treatment. Adsorption tests revealed that BM-FA and ZNa-P1 removed 76% and 90% of TC, respectively, compared to 35% with unmodified FA. AM-FA had the lowest performance, removing just 11% of TC. ZNa-P1’s superior performance was linked to its high zeolite purity, with a cation exchange capacity (CEC) of 6.37 meq/g and a surface area of 35.7 m2/g. Though BM-FA had a larger surface area of 110.8 m2/g, it exhibited a lower CEC of 3.42 meq/g. Adsorption efficiency was more closely related to CEC than surface area. Optimal TC removal with ZNa-P1 was achieved at a 7.5 g/L dosage and pH 5. The process followed pseudo second order kinetics and the Langmuir isotherm, with a maximum capacity of 46.34 mg/g at 30 °C. The adsorption thermodynamics indicated that the adsorption was endothermic and spontaneous. The adsorption mechanism of tetracycline on ZNa-P1 involved electrostatic attraction, hydrogen, and ion exchange. This study aligns with SDGs 6 (Clean Water and Sanitation) and 12 (Responsible Consumption and Production).