Faculty of Humanities and Sciences-Scopus2
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Publication Embargo A Comprehensive Investigation of Microplastic Contamination and Polymer Toxicity in Farmed Shrimps; L. vannamei and P. monodon(Springer Nature, 2025-02-20) Jayaweera, Y. U; Hennayaka, H. M.A.I; Herath, H.M.L.P.B; Kumara, G. M.P; Mahagamage, M.G.Y.L; Rodrigo, U.D; Manatunga, D. CMicroplastic (MP) pollution poses a significant threat to marine ecosystems, seafood safety, and human health. This study investigates the accumulation of microplastics in two commercially important shrimp species, Litopenaeus vannamei (L. vannamei) and Penaeus monodon (P. monodon), sourced from cluster farming sites in Puttalam, Sri Lanka. Shrimp exoskeletons and edible soft tissues underwent rigorous microplastic analysis, including density separation, alkali digestion, stereo microscopy, and Raman spectroscopy. The results revealed high microplastic contamination, with L. vannamei containing an average of 4.99 ± 1.81 MP particles/g and P. monodon containing 1.87 ± 0.55 MP particles/g. Microplastic sizes varied, with L. vannamei predominantly contaminated with 100–250 µm particles and P. monodon with 500 µm—1000 µm particles. Fiber morphotypes were prevalent in L. vannamei, while blue-colored microplastics were dominant in P. monodon. These comprised polystyrene (PS), nylon 6,6, and polyethylene (PE) which were identified by Raman spectroscopy. Additionally, the study investigated the acute toxicity effects of microplastic polymer combinations using a zebrafish embryo model (FET236 assay). Zebrafish embryos exposed to polyethylene-nylon 6,6 combinations exhibited significant adverse effects on hatching, survival, and heart function at lower concentrations, while polyethylene terephthalate-polystyrene combinations showed no considerable effects. These findings underscore the urgent need for monitoring and managing microplastic contamination in shrimp farming areas. Future research should focus on elucidating the ecological impacts and human health risks associated with microplastic exposure.Publication Open Access A novel solid-state, multi-layered biodegradable microbial inoculant system for rice straw composting: biocapsule design, characterization, and performance evaluation(Frontiers Media SA, 2026-04-17) Senadheera, U. E; Jasintha Jayasanka, D; Hewawasam, C; Udayanga, D; Takimoto, Y; Nakayama, TLignocellulolytic microbial inoculants are widely used to enhance lignocellulosic waste composting, but their efficacy is often limited by environmental stress and uncontrolled release when conventional liquid inoculants are used. This study introduces a multi-layered biocapsule structure that sustains lignocellulolytic microbial activity and evaluates its composting efficiency through control experiments. A three-layered biodegradable biocapsule was designed using a rice straw biocomposite, humic acid, activated carbon, corn starch, carboxymethyl cellulose, and calcium alginate beads with encapsulated Klebsiella–Enterobacter consortium immobilized on hydroxyapatite nanoparticles. The biocapsule comprises a rice straw outer biocomposite shell in the outermost layer, a moisture retention hydrogel in the middle, and the encapsulated bacteria in calcium alginate beads in the core. The designed biocapsule was used in three treatments: intact biocapsule, powdered biocapsule, and a control (without inoculants), and the composting efficacy was evaluated against Sri Lankan Standards for compost products. Calcium alginate beads achieved 78.29% ± 9.57% and 84.45% ± 6.04% bacterial encapsulation efficiency and bacterial release, respectively, with heavy bacterial colonization in beads. The entire biocapsule reached 56.16% ± 1.65% biodegradation in 7 days. Intact biocapsule enhanced early lignocellulolysis, faster pH neutralization, and reduced electrical conductivity to 0.62 ± 0.00 while sustaining prolonged thermogenesis above 55 °C for 25 days. The intact biocapsule significantly improved compost nutrient availability, increasing total nitrogen, phosphorus, and potassium levels by 71.89%, 83.0%, and 60.66%, respectively, while achieving a total organic carbon loss of 53.30% and a Carbon: Nitrogen ratio decline of 72.83%.Publication Embargo Activity enhanced TiO2 nanomaterials for photodegradation of dyes-A review(Elsevier, 2021-12-01) Thambiliyagodage, C. JWastewater generation due to anthropogenic activities has become a tremendous problem that the world is struggling to solve. Dyes release to normal water reservoirs badly impacts the environment causing severe issues. Removal of dyes from wastewater streams is important. The advanced oxidation process is advantageous as the dye molecules are degraded into harmless species. TiO2 is the most promising semiconductor that has been researched. However, the use of it in the visible range is restricted due to its high band gap (3.0 eV). TiO2 has been modified in order to enhance visible light sensitivity. This review mainly focused on the effects of doping TiO2 with metals and non-metals and coupling with metal and non-metal oxides to improve its efficiency in photodegrading dyes. TiO2 doped with Fe, Cu and Ag as the main metal species, N, S, and C as the main non-metals are summarized. Further, the effect of doping with multi non-metals and co-doping of metals and non-metals are also discussed. Moreover, coupling TiO2 with metal oxides and graphene oxide for enhanced photocatalytic activity is also summarized in this review.Publication Embargo Analysis of the ‘Toll Free Agricultural Advisory Service’ Data as Decision Support Tool for the Department of Agriculture(IEEE, 2022-07-18) Rajapaksha, N; Dias, NThe Department of Agriculture’s Toll-Free Agricultural Advisory Service was formed with the 1920 short code and is connected to all land and mobile telephone service providers in Sri Lanka. This short code allowed farmers and other stakeholders to contact technical officers which Agriculture Instructors immediately. All the information was gathered into the 1920 call center database. Farmers all over the island bring their agricultural problems to the 1920 Agricultural Advisory Service. Nevertheless, it can be seen that they do not do any analysis of these problems. This big data if properly examined has the potential to assist the country on a massive scale in the future. This study for carrying out to explore the possibility of introducing decision support for the 1920 reporting system to generate enhanced analytics and to make it easier to make informed decisions by the top management of the Department of Agriculture, more efficiently and effectively than the reporting method previously.Publication Embargo Assessing the Efficacy of Machine Learning Algorithms in Predicting Critical Properties of Gold Nanoparticles for Pharmaceutical Applications(Springer Nature Link, 2025-07-08) Fernando, H; Mohottala, S; Jayanetti, M; Thambiliyagodage, CAu nanoparticles are increasingly used in pharmaceuticals, but their synthesis is costly and time-intensive. Machine Learning can help optimize this process. In this research, eight distinct Machine Learning models were implemented and optimized on a dataset comprising 3000 records of gold nanoparticles. The performance of these models was assessed using four accuracy metrics and the time required for training and inference. The results are promising, with all seven models demonstrating high accuracy and low time requirements. Notably, the XGBoost and Artificial Neural Network models exhibited exceptional performance, with Mean Squared Error values of 0.0235 and 0.0098, Mean Absolute Error values of 0.1021 and 0.0674, Mean Absolute Percentage Deviation values of 0.4945 and 0.3590, R2 scores of 0.9995 and 0.9998, and inference times of 0.0029 and 0.4299 s, respectively. The Explainable Artificial Intelligence analysis of the resulting models revealed some interesting insights into how the models make the predictions and what factors heavily contribute to the nanoparticle AVG_R, allowing chemists to optimize the synthesis for gold nanoparticles better. The key contributions of the research include the design and development of eight Machine Learning models using industry-standard frameworks, the training, tuning, and evaluation of these eight models using five different metrics, and further assessment of these trained models using Explainable Artificial Intelligence. The findings indicate a substantial potential for applying neural networks in the design phase of nanoparticle synthesis, which could lead to significant reductions in both the time and cost required for synthesizing Au nanoparticles for pharmaceutical applications.Publication Open Access Ball milling–A green and sustainable technique for the preparation of titanium based materials from ilmenite(Elsevier, 2022-01-01) Thambiliyagodage, C. J; Wijesekera, RIlmenite is a naturally available mineral that is highly applicable in the synthesis of pure TiO2. Titania mainly presents in four polymorphs as rutile, anatase, brookite and TiO2–B. Titania could be mined from minerals such as ilmenite, leucoxene and rutile among which ilmenite is the main source. Ball milling is a mechanical activation method used before subjecting ilmenite to chemical treatment methods to produce titanium based materials. Effect of milling time, milling intensity, milling atmosphere, the introduction of reducing agents on the particle size, surface area, annealing temperature, and the crystal structure of the products are reviewed. The effect of ball milling on acid digestion of ilmenite in hydrochloric acid and sulfuric acid is discussed. Further, the effect of mechanical activation on hydrothermal treatment of ilmenite is explained in detail.Publication Open Access Biochemical shifts in Chlorella vulgaris via post-stationary magnesium sulfate stress: optimizing biomass for advanced bio-fertilizers(Frontiers Media SA, 2026-06-09) Dodangodage, C. A; Kasturiarachchi, J. C; Perera, T.A; Rajapakshe, S.D; Niyangoda, S.S; Halwatura, R.USustainable agriculture requires bio-fertilizers that improve both nutrient efficiency and soil resilience. Microalgae are promising candidates; however, conventional optimization using sodium chloride (NaCl) stress introduces phytotoxic sodium residues that limit soil application. To address this, a biphasic cultivation strategy for Chlorella vulgaris was developed using magnesium sulfate (MgSO4) as a dual-function stressor. Following the onset of a nitrogen-limited stationary phase (Day 18), the addition of 0.4 g L-¹ MgSO4 induced intracellular macromolecular accumulation. Biomass increased by 44.8% (2.810 ± 0.090 g L-¹), driven by intracellular densification, with enrichment in both total carbohydrate (42.15 ± 2.10%) and lipid (36.24 ± 1.11%) fractions. Substituting NaCl with MgSO4 eliminates the risk of sodium-induced phytotoxicity upon soil application, while simultaneously pre-loading the biomass with essential secondary macronutrients. Overall, this study demonstrates that targeted MgSO4-induced metabolic shifts can generate high-density, functionally enhanced, sodium-free microalgal biomass to serve as a potential bio-fertilizer feedstock.Publication Open Access Biocompatibility vs antibacterial activity: chitosan-mediated nanosilver/PCL/gelatin nanofibers(Taylor and Francis Ltd., 2026) Chandraguptha, D; Fernando, L; Herath, L; Godakanda, V. U; Perera, N; Samarakoon, S; de Silva, K. M. N; Williams, G.R; de Silva, W. R.MElectrospinning is an efficient approach to prepare nanofiber scaffolds that mimic local tissue environments. While many reported scaffolds incorporate nanoparticles, detailed assessments of how nanosilver distribution affects antibacterial activity and biocompatibility remain limited. In this study, we developed an electrospun biopolymer scaffold composed of polycaprolactone and gelatin with chitosan-mediated nanosilver (C-AgNPs), introduced either by bulk surface coating or by dispersing the NPs within the electrospinning solution. The C-AgNP surface-coated scaffold exhibited antibacterial activity against Staphylococcus aureus and Escherichia coli, whereas the dispersed scaffold did not. However, the dispersed scaffold promoted higher dermal fibroblast viability (82.7%) compared with the coated scaffold (60.9%). Zebrafish embryo assays further revealed mild developmental toxicity from the coated scaffold but no observable toxicity from the dispersed formulation. These findings demonstrate a distinct trade-off between antibacterial efficacy and cytocompatibility depending on nanoparticle distribution. Understanding this relationship is critical for designing electrospun nanofiber scaffolds with balanced biological properties.Publication Embargo Catalytic graphitization in nanocast carbon monoliths by iron, cobalt and nickel nanoparticles(Pergamon, 2018-08-01) Thambiliyagodage, C. J; Ulrich, S; Araujo, P. T; Bakker, M. GHierarchically porous carbon monoliths containing metal (Fe, Co, Ni) nanoparticles were synthesized in a one-pot synthesis through a nanocasting technique using silica (SiO2) as the template. The macropore structure of SiO2 has been replicated in nanocast carbon and N2 adsorption analysis shows that the monoliths have high surface area, high mesopore volume, and that micropores are also present. The temperature effect on catalytic graphitization was studied by using x-ray diffraction (XRD), transmission electron microscope (TEM) and Raman spectroscopy. It is observed that iron was capable of producing turbostratic carbon at 500 °C, while turbostratic carbon was produced at temperatures of 700 °C when cobalt and nickel are present. Iron, cobalt, and nickel were found to be good graphitization catalysts with the order of catalytic activity being iron > cobalt > nickel. Raman spectroscopy experiments provide insight into the degree of ordering of the carbon of each sample and are in agreement with the results from the other techniques: with increasing pyrolysis temperature, with and without the presence of metals, ordering of amorphous carbon is confirmed. Detailed analysis of the Raman spectroscopic data showed clear differences between the metal catalyzed and non-catalyzed samples enabling the contributions from the two different mechanisms to be clearly distinguished.Publication Open Access Chitosan-Starch Biocomposite for Enhanced Curcumin Delivery: Kinetic Modeling of pH and Ionic Strength Responsive Release and Evaluation of Biological Efficacy(American Chemical Society, 2026-07-21) Abeywickrama, L; Wijayawardana, S; Thambiliyagodage, C; Jayanetti, MA drug delivery system composed of chitosan and starch was used to deliver curcumin effectively by enhancing its pharmacokinetic properties. The sustained release of the synthesized delivery system was evaluated using a kinetic modeling approach along with its biological efficacy. The SEM analysis confirmed the coupling of starch and chitosan and loading of curcumin into the matrix during synthesis. Crystallographic orientation of the delivery system was confirmed by XRD, and the FT-IR data confirmed the successful loading of curcumin. TG analysis indicated that the increment in decomposition temperature of the composite is due to the incorporation of curcumin into the composite. BET analysis revealed the reduction in the BET surface area and pore volume in the synthesized composite, confirming successful loading. The IC50 values of the curcumin and composite for the DPPH assay were 17.81 μg/mL and 38.77 μg/mL, respectively. Composite material has shown enhanced antibacterial activity against Staphylococcus aureus and Pseudomonas aeruginosa at 20 mg/mL, with inhibition zones of 15.56 ± 0.29 and 10.11 ± 0.44 mm, respectively. Allium cepa cytotoxicity assay confirmed that all the synthesized materials promote mitosis at 2.5 mg/mL concentration. The pH and ionic strength responsive release of curcumin was studied by fitting the release data into six kinetic models, including Korsemeyer–Peppas (KP) and Peppas–Sahlin (PS), which has not been reported earlier for the synthesized system. The KP and PS models were selected to interpret the release mechanism based on R2. A combination of Fickian diffusion, relaxation and swelling dominates the curcumin release. According to the KP model, quasi-Fickian diffusion is responsible for the release in acidic and alkaline pH, whereas non-Fickian diffusion occurs at pH 6.7. At higher [NaCl], relaxation is responsible for the release (n > 0.43, kD = 0), while a combination of diffusion and relaxation governs the release at lower [NaCl]. These behaviors are related to the chemical composition of chitosan and the release media, where the electrostatic repulsion, protonation and charge screening contribute to curcumin release.Publication Open Access Chitosan-Starch Biocomposite for Enhanced Curcumin Delivery: Kinetic Modeling of pH and Ionic Strength Responsive Release and Evaluation of Biological Efficacy(American Chemical Society, 2026-07-21) Abeywickrama, L; Wijayawardana, S; Thambiliyagodage, C; Jayanetti, MadaraA drug delivery system composed of chitosan and starch was used to deliver curcumin effectively by enhancing its pharmacokinetic properties. The sustained release of the synthesized delivery system was evaluated using a kinetic modeling approach along with its biological efficacy. The SEM analysis confirmed the coupling of starch and chitosan and loading of curcumin into the matrix during synthesis. Crystallographic orientation of the delivery system was confirmed by XRD, and the FT-IR data confirmed the successful loading of curcumin. TG analysis indicated that the increment in decomposition temperature of the composite is due to the incorporation of curcumin into the composite. BET analysis revealed the reduction in the BET surface area and pore volume in the synthesized composite, confirming successful loading. The IC50 values of the curcumin and composite for the DPPH assay were 17.81 μg/mL and 38.77 μg/mL, respectively. Composite material has shown enhanced antibacterial activity against Staphylococcus aureus and Pseudomonas aeruginosa at 20 mg/mL, with inhibition zones of 15.56 ± 0.29 and 10.11 ± 0.44 mm, respectively. Allium cepa cytotoxicity assay confirmed that all the synthesized materials promote mitosis at 2.5 mg/mL concentration. The pH and ionic strength responsive release of curcumin was studied by fitting the release data into six kinetic models, including Korsemeyer–Peppas (KP) and Peppas–Sahlin (PS), which has not been reported earlier for the synthesized system. The KP and PS models were selected to interpret the release mechanism based on R2. A combination of Fickian diffusion, relaxation and swelling dominates the curcumin release. According to the KP model, quasi-Fickian diffusion is responsible for the release in acidic and alkaline pH, whereas non-Fickian diffusion occurs at pH 6.7. At higher [NaCl], relaxation is responsible for the release (n > 0.43, kD = 0), while a combination of diffusion and relaxation governs the release at lower [NaCl]. These behaviors are related to the chemical composition of chitosan and the release media, where the electrostatic repulsion, protonation and charge screening contribute to curcumin release.Publication Open Access Coconut Shell Waste-Derived Porous Carbon-Supported Sn Catalysts for Efficient Electrochemical CO2Reduction to Formic Acid and Deuterated Formic Acid(American Chemical Society, 2025-11-05) Qin, C; Masakorala, G; Mohideen, M; Samarasekara, T; Zhang, L; Zhu, W; Zhou, Y; Thambiliyagodage, CIndustrial-level electrochemical CO2 reduction reaction (CO2RR) to form HCOO– and DCOO– requires robust Sn catalysts with high performance. In this study, the hydrothermal method was employed to load varying amounts of Sn precursors onto waste biomass-derived porous carbon to investigate the structure–activity relationship between Sn loading forms and HCOO– selectivity. Through comprehensive ex/in situ characterizations, we discovered that with 5% Sn precursor addition, highly dispersed SnO2 nanoparticles formed on the carbon support, enabling the catalyst to exhibit exceptional HCOO– activity (Faradaic efficiency exceeding 90%) across a broad potential window. In situ attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) and in situ Raman spectroscopy revealed that the highly dispersed SnO2 nanoparticles enhance the stability of the *OCHO intermediate. Furthermore, when H2O was replaced with D2O, the generation of DCOO– was observed, and good selectivity was maintained. This study provides a facile strategy for waste biomass conversion and the design of Sn-based catalysts for DCOO– production.Publication Open Access Coordinated lignocellulolysis: topological analysis reveals coordinated lignocellulolysis in Klebsiella–Enterobacter-mediated rice straw degradation via surface delignification and cellulose crystallinity modulation(Microbiology Society, 2026-05-12) Senadheera, U. E; Jayasanka, D.J; Hewawasam, C; Udayanga, D; Takimoto, Y; Tadachika, NSurface-sterilized Oryza sativa AT362 straw was screened for endophytic ligninolytic and cellulolytic bacteria using colour unit reduction and Congo Red decolorization assays. Ligninolytic Klebsiella variicola AKL1104 and cellulolytic Enterobacter chuandaensis AKC1108, biocompatible, were inoculated at a 1:1 ratio and incubated in 1% (w/v) rice straw broth at 37 °C for 7 days. Topological changes due to degradation were conducted using scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) for 9 days. During t=9 d, SEM shows vascular tissue perforation with tunnels, indicating K. variicola mediated-delignification, allowing E. chuandaensis to sequentially degrade cellulose. XRD revealed a cellulose crystallinity decline from 30.08% on t=0 d to 11.76% on t=9 d. Electron microscopy and crystallite size calculations in t=6 d (6.81 nm) and t=9 d (90.16 nm) indicate self-assembly of cellulose fibrils. FTIR and XPS analysis indicated crystalline cellulose transformation to amorphous cellulose as the lateral order index dropped from 0.776±0.006 to 0.503±0.007, while surface lignin coverage was reduced from 5.01 to 2.20%, respectively.Publication Open Access Copper-Based Nanoparticles as Precision Nanoantibiotics against Bacterial Blight in Anthurium andraeanum Lind.: Synthesis, Characterization, and Antibacterial Efficacy under In Vitro and In Vivo Conditions(American Chemical Society, 2026-05-05) Wanaguru, S; Jayasinghe, S; Seneviratne, K; Kottegoda, N; Peiris, Sriyani E; Peiris, Colin NThe bacterial blight disease caused by Xanthomonas spp., a dilemma for farmers worldwide. The existing conventional methods have failed to effectively combat the disease. Therefore, it is crucial to focus on developing and implementing more affordable techniques to effectively manage bacterial blight effectively. Herein, we investigated the efficacy of copper-based nanoparticles (Cu NPs) synthesized via three different methods toward controlling bacterial blight disease in Anthurium andraeanum plants. For that, Cu NPs were engineered via chemical, semichemical, and green synthesis approaches. Cu NPs were characterized through scanning electron microscope (SEM), transmission electron microscope (TEM), Fourier-transform infrared (FTIR), and powder X-ray diffraction (PXRD) analysis. Quantitative antibacterial assays revealed that the chemical and green-synthesized Cu NPs exhibited the highest potency, with a minimum inhibitory concentration (MIC) of 31.25 μg/mL and a minimum bactericidal concentration (MBC) of 62.50 μg/mL, whereas the semichemical formulation showed lower activity (MIC = 62.50 μg/mL; MBC = 125 μg/mL). In vitro well-diffusion assays further supported this trend: at 30 ppm, the inhibition zones measured 25 ± 0.81, 15 ± 0.81, and 20.6 ± 0.94 mm for the chemical, semichemical, and green synthesis methods, respectively, compared to 26.3 ± 0.47 mm for the positive control-antibiotic sulfamethoxazole. At in vivo, optimized concentration of 200 ppm, Cu NPs produced via all three methods controlled bacterial blight disease in 90% of treated anthurium plants within 4, 7, and 5 weeks, respectively, without causing phytotoxicity. Disease progression was monitored over 12 weeks by measuring lesion areas, and statistical significance of treatments was determined using two-way analysis of variance (ANOVA). ©Publication Open Access Correlation between molecular diversity and biochemical traits of edible aerial parts of Basella alba L. from different geographical locations of Sri Lanka(BioMed Central Ltd, 2025-12-29) Dahanayaka, L. W.; Mapa, M. M. S. T; Kadigamuwa, C.C; Udayanga, DBackground: Basella alba L. a widely consumed green leafy vegetable, exhibits considerable nutritional and therapeutic potential attributed to its bioactive constituents. Prior investigations revealed significant variation in phytochemical and antioxidant activity across agro-climatic zones in Sri Lanka, suggesting potential genetic influence. This study is designed to explore underlying genetic variation using RAPD markers to investigate the correlations and contributions of genotype on previously reported bioactivity variation. Results: From a screening of 15 RAPD primers, four primers (OPA 9, OPA 10, OPA 16, and OPB 10) produced, polymorphic, consistent and clearly scorable banding profiles (under optimized PCR conditions) in B. alba L. collected from 15 Sri Lankan locations. These primers collectively yielded 36 bands, 35 of which were polymorphic, resulting in a high polymorphism rate of 97.2%, confirming the informativeness of the selected primers for genetic diversity analysis. Genetic similarity was assessed using Jaccard’s coefficient in NTSYSpc.v2·10e, revealing values ranging from 0.44 to 0.97, with the highest similarity from the samples from Ratnapura and Kandy and the lowest similarity in Ratnapura and Kalutara. A dendrogram constructed via UPGMA grouped the samples into two major clusters and five sub-clusters, demonstrating substantial genetic differentiation influenced by geographic origin. Cluster I included Ratnapura and Kandy, while the remaining samples formed Cluster II and its subgroups, each representing different ecological zones. When compared to the phytochemical and antioxidant clustering data of the previous study, partial correspondence was observed. A Mantel test comparing genetic diversity and biochemical/antioxidant potential revealed a weak negative correlation which was not significantly different. Some of the locations within similar genetic cluster shared similar biochemical traits, while others diverged significantly, indicating that environmental conditions also influence bioactive compound synthesis. Notably, Cluster I (Ratnapura and Kandy) showed both genetic similarity and lower antioxidant traits. Samples from Ella and Polonnaruwa showed similar bioactive traits even though they were grouped into different genetic clusters. Conclusion: These findings suggest that both genetic makeup and environmental adaptation contribute to observed biochemical diversity in B. alba L. with a clear geographical correlation. This study highlights the value of integrating molecular and biochemical analyses to develop regionally adapted B. alba L. cultivars with enhanced nutritional traits, supporting sustainable agriculture in Sri Lanka and beyond.Publication Open Access Detecting a decline in serial homicide: Have we banished the devil from the details?(Cogent, 2019-01-01) Yaksic, E; Allely, C; De Silva, R; Smith-Inglis, M; Konikoff, D; Konikoff, K; Gordon, D; Denisov, E; Keatley, D. AThe current research provides perspective regarding the true prevalence of serial murderers in modern society and addresses the conflict between the evidenced decline in serial homicide and the viewpoint that the phenomenon is increasing. The likelihood that serial murderers are responsible for most unresolved homicides and missing persons is examined in the context of a declining prevalence. A mixed methods approach was used, consisting of a review of a sample of unresolved homicides, a comparative analysis of the frequency of known serial homicide series and unresolved serial homicide series, and semi-structured interviews of experts. In failing to become serial killers, aspiring and probable serial killers and spree killers have impacted the rate of serial murder by not reaching their potential. The past decade contained almost half the cases (13%) that existed at the 1980s peak of serial homicide (27%). Only 282 (1.3%) strangled females made up the 22,444 unresolved homicides reviewed. Most expert respondents thought it unreasonable that any meaningful proportion of missing persons cases are victims of serial homicide. Technology, shifts in offending behavior, proactive law enforcement action, and vigilance of society have transformed serial killing and aids in viewing offenders as people impacted by societal shifts and cultural norms. The absence of narrative details inhibited some aspects of the review. An exhaustive listPublication Embargo Development of the major triterpenoids and oil in the fruit and seeds of neem (Azadirachta indica)(No longer published by Elsevier, 1996-09-01) JOHNSON, S; MORGAN, D. E; PEIRIS, C. NIn order to learn the best time for harvesting Neem (Azadirachta indica) seeds, the amount of the five major triterpenoids, together with the oil content have been determined throughout a fruiting season in six selected trees in Sri Lanka. The triterpenoid content and the relative proportions of the major compounds changed little from the hard green fruit stage to mature seeds, while the oil content increased markedly with time. The highest content of azadirachtin (10 mg g-1seed kernels) was recorded in newly ripened seeds. There was some loss of salannin and azadirachtin in storage after harvesting for up to 6 months.Publication Open Access Early Diagnosis and Severity Assessment of Weligama Coconut Leaf Wilt Disease and Coconut Caterpillar Infestation Using Deep Learning-Based Image Processing Techniques(Institute of Electrical and Electronics Engineers Inc., 2025-02-07) Vidhanaarachchi, S; Wijekoon, Janaka L; Abeysiriwardhana, W. A. S. P; Wijesundara, Mlobal Coconut (Cocos nucifera (L.)) cultivation faces significant challenges, including yield loss, due to pest and disease outbreaks. In particular, Weligama Coconut Leaf Wilt Disease (WCWLD) and Coconut Caterpillar Infestation (CCI) damage coconut trees, causing severe coconut production loss in Sri Lanka and nearby coconut-producing countries. Currently, both WCWLD and CCI are detected through on-field human observations, a process that is not only time-consuming but also limits the early detection of infections. This paper presents a study conducted in Sri Lanka, demonstrating the effectiveness of employing transfer learning-based Convolutional Neural Network (CNN) and Mask Region-based-CNN (Mask R-CNN) to identify WCWLD and CCI at their early stages and to assess disease progression. Further, this paper presents the use of the You Only Look Once (YOLO) object detection model to count the number of caterpillars distributed on leaves with CCI. The introduced methods were tested and validated using datasets collected from Matara, Puttalam, and Makandura, Sri Lanka. The results show that the proposed methods identify WCWLD and CCI with an accuracy of 90% and 95%, respectively. In addition, the proposed WCWLD disease severity identification method classifies the severity with an accuracy of 97%. Furthermore, the accuracies of the object detection models for calculating the number of caterpillars in the leaflets were: YOLOv5-96.87%, YOLOv8-96.1%, and YOLO11-95.9%.Publication Open Access Early Diagnosis and Severity Assessment of Weligama Coconut Leaf Wilt Disease and Coconut Caterpillar Infestation Using Deep Learning-Based Image Processing Techniques(Institute of Electrical and Electronics Engineers Inc., 2025-02-03) Vidhanaarachchi, S; Wijekoon, J. l; Abeysiriwardhana, W. A. S.P; Wijesundara, MGlobal Coconut (Cocos nucifera (L.)) cultivation faces significant challenges, including yield loss, due to pest and disease outbreaks. In particular, Weligama Coconut Leaf Wilt Disease (WCWLD) and Coconut Caterpillar Infestation (CCI) damage coconut trees, causing severe coconut production loss in Sri Lanka and nearby coconut-producing countries. Currently, both WCWLD and CCI are detected through on-field human observations, a process that is not only time-consuming but also limits the early detection of infections. This paper presents a study conducted in Sri Lanka, demonstrating the effectiveness of employing transfer learning-based Convolutional Neural Network (CNN) and Mask Region-based-CNN (Mask R-CNN) to identify WCWLD and CCI at their early stages and to assess disease progression. Further, this paper presents the use of the You Only Look Once (YOLO) object detection model to count the number of caterpillars distributed on leaves with CCI. The introduced methods were tested and validated using datasets collected from Matara, Puttalam, and Makandura, Sri Lanka. The results show that the proposed methods identify WCWLD and CCI with an accuracy of 90% and 95%, respectively. In addition, the proposed WCWLD disease severity identification method classifies the severity with an accuracy of 97%. Furthermore, the accuracies of the object detection models for calculating the number of caterpillars in the leaflets were: YOLOv5-96.87%, YOLOv8-96.1%, and YOLO11-95.9%.Publication Embargo Effect of Co-pollutants on the Photocatalytic Activity of Fe doped ZnO Nanoparticles on the Degradation of Methylene Blue(IEEE, 2022-07-18) Thambiliyagodage, C; Lokuge, NZnO nanoparticles and Fe doped ZnO nanoparticles with varying Fe concentrations as 0.025, 0.05, 0.075, and 0.1% respective to Zn, was successfully synthesized by the sol-gel method. Synthesized nanoparticles were characterized by X-ray diffractometry (XRD) and Raman spectroscopy. As revealed by both studies Fe has successfully doped to ZnO without causing any lattice distortions. Synthesized catalysts were photocatalytically active in degrading methylene blue under sunlight. The effect of co-pollutants; Rhodamine B, Pb 2+ , PO43− and S2O32− on the rate of photodegradation was studied and it was found that Rhodamine B, Pb 2+ , and PO43− reduce the rate and S2O32− increases the rate of photodegradation.