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Publication Open Access Anthocyanin (ATH)-incorporating polyvinylpyrrolidone-ethyl cellulose-(2-hydroxypropyl)-β-cyclodextrin (PVP–EC–BCD) nanofiber-based pH sensor for ocular pH detection during accidental chemical spills(Royal Society of Chemistry, 2026-02-03) Sandaruwan, B; Liyanage, R; Costha, P; Dassanayake, R.S; Wijesinghe, R.E; Herath H.M.L.P.B.; Nalin de S.K.M; de Silva, R.M; Rajapaksha, S.M; Wijenayake, U; Manatunga, D.CThe existing ocular pH detection methods encounter numerous limitations, including low accuracy, poor sensitivity across a wide pH range, and patient discomfort, highlighting the need for innovative approaches. A novel biosensor for ocular pH detection has been developed to assess ocular health and chemical injuries in clinical settings. This study uses the pH-sensitive properties of anthocyanins (ATHs), natural pigments extracted from butterfly pea flowers, to develop a novel pH-responsive nanofiber mat. ATHs are integrated into a polymer blend containing polyvinylpyrrolidone (PVP), ethyl cellulose (EC), and (2-hydroxypropyl)-β-cyclodextrin (BCD) to fabricate electrospun nanofibers. The acquired characterization, employing scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and thermogravimetric analysis (TGA), confirmed the successful fabrication of the ATH-infused nanofibers with a mean diameter ranging from 121 to 396 nm. Four formulations were tested: PVP:EC:BCD:ATH (18 ppm), PVP:EC:BCD:ATH (25 ppm), PVP:EC:BCD:ATH (35 ppm), and PVP:EC:BCD:ATH (50 ppm). Among them, the 50 ppm ATH-incorporating nanofiber mat exhibited the best performance in terms of color clarity, response time, and pH sensitivity. The fabricated 50 ppm ATH incorporating nanofiber mat demonstrated a rapid pH response time of less than 5 seconds (s) while exhibiting a color variation from pink to blue to green across the pH range of 1 to 12, providing a rapid and accurate method for visual pH detection. Based on the color performance of the 50 ppm ATH-incorporating system, a standardized color reference chart was developed to serve as a practical and visual guide for estimating pH levels in clinical applications. Zebrafish toxicity assays were conducted further to validate the safety and biocompatibility of the developed sensor, revealing no significant toxic effects across the range of ATH concentrations.Publication Open Access Nature-Based Urban Drainage Solutions Using Industrial Waste-Incorporated Pervious Concrete Pavements(Multidisciplinary Digital Publishing Institute (MDPI), 2026-03-11) Ratnapala, N; Miguntanna, Nandika; Miguntanna, Nadeeka; Rathnayake, UPervious concrete pavements have gained increasing attention as a sustainable stormwater management solution due to their ability to reduce runoff volume and improve water quality through infiltration. This study investigates the stormwater runoff treatment potential and performance efficiency of pervious concrete pavements incorporating industrial waste materials, namely recycled concrete aggregate (RCA), ceramic waste (C), and waste tires (T), as partial replacements for natural coarse aggregates. Concrete mixes were prepared by replacing 10%, 20%, and 30% of the coarse aggregate volume with each waste material, and the results were compared with normal pervious concrete. Stormwater runoff treatment performance was evaluated by analyzing key water quality parameters, including total suspended solids (TSSs), pH, turbidity, color, and electrical conductivity (EC), using collected urban runoff samples. In addition, mechanical properties (compressive, tensile, and flexural strength) and hydraulic properties (porosity and infiltration rate) were assessed to ensure structural and functional suitability. The results demonstrate that pervious concrete pavements incorporating industrial waste materials exhibit effective pollutant removal while maintaining acceptable mechanical performance in accordance with ASTM standards. Among the investigated pervious concrete types, pavements containing 10% recycled concrete aggregate and 10% ceramic waste showed superior reductions in TSS, turbidity, and color compared to other waste-based and normal pervious concrete mixes. This study demonstrated significant reductions in particulate pollutants (TSS, turbidity, and color), while increases in pH and electrical conductivity highlighted early-age ion leaching from the concrete matrix, underscoring both the treatment benefits and the need for long-term monitoring under realistic deployment conditions. Overall, the findings highlight the potential of industrial waste-based pervious concrete pavements as an environmentally sustainable and effective solution for urban stormwater management.Publication Embargo Infill Masonry Strut Models in Reinforced Concrete Frames: Multilevel Reliability Analyses for Predicting In-Plane Responses(John Wiley and Sons Inc, 2026-03-10) Raheem, S; Thamboo, J; Mallikarachi, C; Wijesundara, K; Dias, PThe moment-resisting reinforced concrete (RC) frame infilled with masonry walls is a common form of construction for low- to medium-rise buildings. The importance of considering the infill masonry walls (IMW) in seismic analysis is accentuated due to the interaction between infills and the surrounding frame. Several analytical IMW models have been proposed to model IMW as equivalent diagonal struts, and the appropriateness of those models has been justified through experimental and numerical calibrations. However, the reliability of those analytical models is not well substantiated. Therefore, the reliabilities of five different analytical models have been evaluated herein using the First-Order Reliability Method (FORM). The stochastic uncertainties involved in predicting the in-plane capacities of IMW-RC frames have been incorporated in the reliability analyses. Subsequently, reliabilities of IMW models have been ascertained using experimental data sets compiled at two different scales, namely (1) single story–single bay and (2) multistory IMW-RC frames. 120 experimental data sets of single story–single bay IMW-RC frames tested under in-plane loading and three multistory IMW-RC frames tested on shake-tables were used to assess the reliabilities of IMW models. The results showed that the IMW models considered have predicted the in-plane behavior of IMW-RC frames (single or multistory) to certain levels of accuracy. The predicted reliability indices (β values) of the models vary between 1.03 and 4.13. The reliabilities differ when different aspects of the predictions are being considered, such as peak or ultimate load and drift capacities of single story–single bay frames or base shear and story drift of multistory frames. Therefore, depending on the requirement (strength- or displacement-based design), the IMW models should be selected appropriately to carry out the seismic analyses of IMW-RC buildings.Publication Open Access Status Quo Bias and EV Adoption: A Prospect Theory Perspective from a Developing Country Context(Multidisciplinary Digital Publishing Institute (MDPI), 2026-04-01) Theekshana, D; Gamage, K. A.A; Herath, R; Kavirathna, C.A; Jayasinghe, S; Weerakkody W.A.SElectric vehicles (EVs) are promoted to decarbonise road transport, yet uptake remains slow in many emerging markets. This study examines consumer resistance to EV adoption in Sri Lanka by modelling status quo bias (SQB) using a Prospect Theory lens. An online survey of urban vehicle owners and near-term buyers yielded 157 responses; after screening and removing influential outliers, 151 cases were analysed using partial least squares structural equation modelling (PLS-SEM). The model tests five Prospect Theory-aligned antecedents, namely, loss aversion, reference dependence, risk perception, framing effects, and uncertainty aversion, and evaluates environmental concern as a moderator. Results indicate that loss aversion has a significant positive effect on SQB (β = 0.216, p = 0.005) and uncertainty aversion is the strongest predictor (β = 0.453, p < 0.001), while reference dependence, risk perception, and framing effects show positive but statistically non-significant direct effects. Moderation tests show that environmental concern significantly moderates the effects of reference dependence (β = 0.181, p = 0.039) and framing effects (β = 0.179, p = 0.037) on SQB, but does not significantly moderate the loss aversion, risk perception, or uncertainty aversion paths. Overall, perceived losses and—especially—ambiguity surrounding EV ownership appear to sustain reliance on internal combustion vehicles in this developing-country context, underscoring the need for interventions that reduce uncertainty (credible infrastructure signals, stable policy, serviPublication Embargo E-commerce success redefined: integrating information systems and customer empowerment for e-customer engagement(Emerald Publishing, 2026-03-17) Boyagoda, G; Thalagala, S.M; Pathirana, S.L; Jeewantha, S; Wisenthige, KPurpose – This study aims to explore the impact of system quality, information quality, service quality and customer empowerment on customer satisfaction and e-commerce success in Sri Lanka, focusing on Millennials and Generation Z. By integrating the DeLone and McLean Information Systems Success (D&M ISS) model with customer empowerment theory, the research seeks to provide insights into the key drivers of e-customer engagement in e-commerce. Design/methodology/approach – A structured questionnaire was used to collect data from 413 respondents employing the purposive sampling technique. The data collection instrument comprised 32 questions related to system quality, information quality, service quality, customer empowerment and customer satisfaction, as well as demographic questions. The data were analysed using Partial Least Squares Structural Equation Modelling (PLS-SEM). Findings – The results revealed that the system quality, information quality and service quality significantly influence customer satisfaction and intention to use the system in the context of e-commerce, which leads to higher customer engagement. Furthermore, the findings substantiate the crucial role that customer empowerment plays in terms of increasing customer satisfaction. Research limitations/implications – This study focuses on Millennials and Generation Z e-customers in Sri Lanka. It provides insights into this demographic, but does not capture the diverse cultural and technological landscape of the entire country. The study examines Information System (IS) dimensions and customer empowerment, excluding other significant variables like overall customer engagement. Self-reported data may introduce biases, and future research with larger sample sizes and different methods could improve the validity. Focusing on four selected online shopping platforms may limit the applicability as the e-commerce landscape is continuously evolving. Practical implications – The findings offer guidance to e-commerce businesses and policymakers to enhance their digital services and customer satisfaction. Businesses can improve their system quality with intuitive designs, offering accurate information to boost engagement and deliver excellent service quality. Initiatives such as interactive tools, loyalty programs and tailored support can empower customers, fostering a stronger impact. Policymakers can support e-commerce growth by improving regulations and providing training programs. These measures contribute to a more efficient and satisfying online shopping experience, driving long-term customer loyalty and business growth. Social implications – The research emphasises the role of customer empowerment in fostering customer engagement, contributing to the growth of the digital economy and enhancing online shopping experiences. Originality/value – This research enhances the academic understanding of e-commerce success by strengthening the DeLone and McLean Information Systems Success model by adding the concept of customer empowerment. This unique improvement is applied in the context of Sri Lanka, an emerging market with its own socio-economic characteristics. This addition provides new insights into key factors affecting e-customer engagement in the e-commerce sector.Publication Embargo Focus on Middle East and Central Asia: rationale of IMF assistance seeking(Springer Science and Business Media Deutschland GmbH, 2026-03) Wisenthige, K; Pathiranage, H. S.K; Jayathilaka, RThis study delves into the rationale behind the tendency of nations in the Middle East and Central Asia (MECA) to seek aid from the IMF. The IMF supports global financial stability, aiming to foster economic growth and prosperity across its member countries by promoting policies that encourage monetary cooperation and financial resilience. The study employs a conditional fixed-effects logit model, the analysis spans 22 years of data from twenty-five MECA countries to identify the factors driving these nations to seek IMF assistance. It focuses on six determinants: Current Account Balance (CAB), Inflation (INF), Corruption (CORR), General Government Net Lending and Borrowing (GGNLB), General Government Gross Debt (GGGD), and Gross Domestic Product Growth (GDPG). The fixed-effects logit shows that slower GDP growth raises the odds of an IMF programme, while short-run changes in corruption control and public debt ratios are not significant once country and year effects are absorbed. Inflation is weakly positive; the current account balance is still insignificant. A post-GFC and an income-group robustness check confirm the pattern. Furthermore, the study identifies Lebanon, a lower-middle-income country, as a leading example of seeking IMF assistance during the study period. Overall, this research highlights the importance of policymakers understanding the dynamics and rankings within the MECA region to effectively address economic challenges, provide financial support, and foster a more sustainable economic structure.Publication Open Access Achieving zero hunger: A global policy lens on food security drivers and income group disparities(Elsevier B.V., 2026-03) Pulle, N; Sampath, P; Perera, S; Wijayaweera, D; Jayathilaka, RMany countries struggle to meet their daily dietary requirements despite numerous attempts to address the existing demand. Consequently, this study collectively analyses the impact of urbanisation, renewable energy, greenhouse gas emissions, population growth, gross domestic product per capita and agricultural land on food production relying on Sen's Entitlement Theory, thus providing insights to resolve the long-standing issue of food insecurity, and support the achievement of the Sustainable Development Goals. The study utilises a stepwise panel ordered Probit model on 146 countries, for the years 1993 to 2023. It further categorises the food production index into three categories of food security as; low, moderate and high, thereby enabling discussion of the likelihood of a country falling into one of the aforementioned food security categories over the years. Urbanisation, agricultural land, and the dummy variables introduced to represent the income groups have been identified to have a significant and favourable relationship with the food production index. In contrast, the greenhouse gas emissions and renewable energy variables have a significantly inverse impact on the food production index. This makes a unique contribution to the existing body of literature, especially by comparing odds over the years, across different food secure categories, countries, and their specific income levels. This study enables policymakers to gain a comprehensive historical perspective on each case. This study further promotes the Sustainable Development Goals, highlighting areas where these goals have been negatively impacted. Additionally, the study discusses optimised investment allocations, agricultural research and development, agricultural technology, climate resilient farming, and sustainable urbanisation planning as solutions for extreme cases.Publication Embargo Expanding STEM education in low- and middle-income countries: Evidence from policy reforms in Sri Lanka(Elsevier Ltd, 2026-03-01) Priyadarshana, IGovernments in low- and middle-income countries (LMICs) are increasingly investing in STEM education to enhance youth employability and economic growth. Yet, the success of such initiatives depends on students’ responses, which are shaped by their perceptions, motivations, and institutional context. This study examines the effectiveness of two parallel government interventions in Sri Lanka aimed at increasing high school enrollment in STEM subjects: (1) introducing a new Technology stream and (2) upgrading selected schools to offer the Science stream. Using nationwide school census data from 2008 to 2021 and a Difference-in-Differences approach, the study compares the impacts of these interventions on student enrollment patterns across STEM and non-STEM majors. The results show that the introduction of the Technology stream had a significantly larger impact on increasing STEM enrollment and reducing non-STEM enrollments—especially among male students and those in provincial schools—compared to the Science stream intervention. The study draws on education economics and psychological theories to explain these differences, highlighting the roles of perceived returns, self-efficacy, and student interest orientation. The findings underscore the need for STEM policies to align with both student characteristics and broader systemic structures. Insights from Sri Lanka may be relevant to other LMICs where educational reforms must navigate stratified school systems, constrained resources, and persistent gender disparities in STEM participation.Publication Open Access Circular Valorization of Post-Industrial Textile Waste in Thermal-Insulating Cementitious Ceiling Sheets(Multidisciplinary Digital Publishing Institute (MDPI), 2026-02-27) Fernando, K. V; Dodangodage, C.A; Seneviratne, V.M; Jayasinghe, S.M; Dharmaratne, D.D; Gamage, G.N; Halwatura, R. H; Gunasekera U.S.W; Halwatura, R.UThe construction sector faces increasing pressure to reduce the embodied energy of building materials while valorizing industrial waste streams. This study evaluates the direct incorporation of post-industrial textile waste (100% cotton and cotton–polyester blends) in its native form to develop high-performance cementitious ceiling sheets. Composites were fabricated under a controlled hydraulic compaction pressure of 2.0 MPa, optimized to achieve matrix densification while preserving the integrity of the fibrous network. Viscoelastic recovery of the compressed fibers induced a hierarchical double-porosity architecture characterized by macro-voids and hollow fiber lumens. This microstructural evolution reduced thermal conductivity to 0.091 W/m·K, approximately 50% lower than commercial cement–fiber benchmarks—without compromising mechanical compliance. Scanning Electron Microscopy (SEM) revealed a mechanistic decoupling between water absorption and dimensional stability. Although the CP15 formulation (15 wt.% cotton–polyester) exhibited high moisture uptake (~21%), thickness swelling remained limited to 1.35%. This dimensional stability is attributed to the hydrophobic polyester framework, which bridges microcracks and constrains hygroscopic expansion within the cellulosic phase. The optimized CP15 composite achieved a Modulus of Rupture (MOR) of 8.75 MPa, exceeding ISO 8336 Category C, Class 2 requirements. Despite increased thickness, the areal density (10.84 kg/m2) remains compatible with standard gypsum-grade suspension systems, eliminating the need for structural modification. These findings establish a scalable, direct-valorization strategy for circular construction materials delivering enhanced thermal insulation and robust performance under tropical climatic conditions.Publication Open Access A cross-category analysis of high impact low occurrence (HILO) disasters(Elsevier Ltd, 2026-03-19) Samaraweera, U; Kulatunga, U; Dias, PThis paper explores six High Impact Low Occurrence (HILO) disasters, generating insights from five different categories associated with them, namely causes (geophysical, technological, biological, sociological), phases (preparedness, response, recovery), dimensions (socio-economics, governance, equity), sectors (health, education, infrastructure, economy) and national contexts with differing levels of economic development. The process involved the generation of a questionnaire, based on a literature review; and the subsequent analysis and discussion of the questionnaire responses made by six experts nominated by six academies of science in Asia. The findings highlight the limitations of probabilistic, frequency-based risk models for HILO disasters and instead emphasise the importance of scenario-based (worst-case) analyses; mechanisms that preserve inter‐generational knowledge, institutional continuity and community‐based early‐response networks; strengthening community resilience while ensuring equity; and making appropriate investments for increasing preparedness, if not through structural interventions, at least through sustained awareness programs and periodic drills. Theoretical contributions include arguments that institutional capacity, governance quality, and social resilience are more decisive determinants of HILO event outcomes than probabilistic risk analyses; and that effective preparedness depends more on anticipatory planning, scenario-based training and institutionalised memory rather than experiential learning; thus advancing HILO theory beyond event-centred and frequency-driven interpretations towards a more governance- and resilience-oriented understanding.