ICAPS 2024

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Evaluating heavy metal accumulation in Scylla serrata (mud crabs) inhabiting the Negombo lagoon, Sri Lanka
(Faculty of Science, University of Kelaniya Sri Lanka, 2024) Dias, B. C. G.; De Silva, D. S. M.; Amarathunga, A. A. D.; Bakir, A.; McGoran, A. R.; Sivyer, D. B.; Reeve, C.
A multitude of anthropogenic and industrial uses lead to the extensive dispersion of heavy metals in aquatic environments. The protracted presence and poisonous nature of heavy metals inflict negative impacts including organ malfunction and the inactivation of enzymes in aquatic organisms. The bottomdwelling mud crabs are frequently used as bioindicators for evaluating such heavy metal contamination in lagoons and estuaries. Therefore, the main emphasis of this study was on the amounts of heavy metals found in the meat of the Scylla serrata mud crab that lives in Negombo Lagoon, Sri Lanka. Due to their great sensitivity, mud crabs, bottom dwelling crustaceans that live in the bottom zones of lagoons, are frequently utilized as indicators for evaluating heavy metal contamination. Mud crab samples (n = 42) were randomly collected from the Negombo Lagoon from March to May 2023. Three replicates, 1 g each, of the flesh from each crab sample, were treated to acid digestion (conc. HNO3 and H2O2) and analysed separately using an atomic absorption spectrophotometer (AAS). Cu, Fe, Mn, and Zn were found to be the most common heavy metals in crab flesh based on the metal analysis. The amounts of Cd and Cr were not detectable. Zn (0.70 ± 0.24 mg/L) was the most prevalent heavy metal in the meat, followed by Mn (0.08 ± 0.07 mg/L), Cu (0.15 ± 0.12 mg/L), and Fe (0.46 ± 0.30 mg/L). The study's findings support the notion that the mud crabs living in the Negombo Lagoon have heavy metals in their meat. A recent study offers strong proof that heavy metals are present in mud crabs, a popular edible shellfish in Sri Lanka. The Negombo Lagoon's whole food chain may be affected by this contamination.
Placental abnormalities observed among stillbirths, Kandy district, Sri Lanka
(Faculty of Science, University of Kelaniya Sri Lanka, 2024) Alahakoon, A. M. S. S.; Rathnayake, C.; Tennakoon, S.; Karunakaran, K.
Stillbirths are a major concern of the health system of a country as it is a tragic event both for the mother and the society. The placenta of a stillborn baby may have evident anatomical and physiological changes that deviate from the typical appearance of a healthy placenta. These variations could be a cause for the foetal demise in utero. Our study aimed to determine remarkable gross abnormalities identified among placentae of stillbirths. A cross-sectional study was conducted in the National Hospital Kandy, Teaching Hospital Peradeniya, Base Hospital Gampola, and District General Hospital Nawalapititya, for one year from April 2017. The placentas, including umbilical cords of stillbirths that completed 22 weeks of period of amenorrhoea were examined to assess the presence of abnormalities. All consecutive cases were included in the study from the beginning for one whole year. Of 213, placentae that had irregular shapes were 4 (1.9%), and all had complete cotyledons. Two (0.9%) had succenturiate lobes, and one (0.5%) had incomplete membranes. Retroplacental blood clots were observed in 48 (22.5%). Placental infarcts were seen in 25 (11.7%). Among the 211 umbilical cords observed, 195 (92.4%) depicted normal insertion at the placental site. Abnormal insertions observed were battledore (n=13, 6.2%), furcate (n=2, 0.9%) and velamentous (n=1, 0.5%). The number of true umbilical cord knots, nuchal entanglement, umbilical cord hemorrhages, and two cord blood vessels were 4 (1.9%), 24 (11.4%), 46 (21.8%), and 1 (0.5%) respectively. The mean umbilical cord length was 39.4cm. Our study found apparent gross abnormalities in the placentas and umbilical cords among stillbirths. Hemorrhages in both placentae and the umbilical cord, and placental infarcts showed higher incidences compared to other changes. Direct impact on the foetus can be found in the cases of true cord knots ceasing blood supply to the foetus, as well as nuchal entanglement that was leading to asphyxia. Furthermore, the mean cord length in the study was shorter than the normal average length. In-depth laboratory investigations are needed to determine their direct or indirect association with stillbirth. Moreover, national-level values for umbilical cord length must be made for future references and better evaluation.
Investigating the effluent quality of a sewage treatment plant in the Kelaniya area: A temporal analysis
(Faculty of Science, University of Kelaniya Sri Lanka, 2024) Jayasekara, J. M. P. M.; Najim, M. M. M.
Sewage treatment focuses on effectively removing contaminants from sewage to produce an effluent that is safe for discharge into the environment or reuse. Monitoring the effluent quality of a wastewater treatment plant is crucial for maintaining the treated effluent quality. There are growing concerns about the potential environmental impacts of the selected sewage wastewater treatment plant (SWWTP). However, there is a lack of comprehensive research to assess the actual impact of SWWTP on the local environment. Hence, the current study investigated the quality of the effluent of the selected SWWTP. This study was conducted by analysing variations of effluent quality parameters over 6 months (August 2023 to January 2024). Water samples were collected monthly and analysed for key water quality indicators using APHA methods. Temperature, pH, Dissolved Oxygen (DO), Biological Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Total Suspended Solids (TSS), Total Dissolved Solids (TDS), conductivity, salinity, and flow velocity were measured as key water quality indicators. The values of each parameter were compared with the tolerance limits for the discharge of wastewater or effluent into Inland Surface Waters presented by the National Environmental (Protection and Quality) Regulations. The temporal variations of the studied parameters of water samples were statistically analysed using a One-way ANOVA. Results suggest that COD values exceeded the standard values in August (654±16.8 mg/L), October (336.5±35.4 mg/L), November (273±16.8 mg/L), and January (95.2±11 mg/L). TSS values exceeded the standard values in August (87±14.2 mg/L) and October (60±1.74 mg/L) and Dissolved oxygen did not reach the standard values in October (4.47±0.09 mg/L) and November (4.46±0.03 mg/L). Nitrate concentration exceeded the standard values in August (16±1.14 mg/L) and January (13.54±1.04 mg/L). All the other parameters lay within the range of standard values. The cluster analysis of water quality parameters was used to identify the similarities between the sampling sites, and it revealed that effluent released into the environment in August has very different water quality values than other sampling months. All the parameters except pH exhibit significant temporal fluctuations. Low DO level suggested limitations in the aeration process or overload of the organic matter. Low DO levels can affect microbial activities and chemical reactions. Ultimately this can lead to elevated levels of COD and BOD. In addition, sand filtration and carbon filtration are not sufficient to remove soluble organic matter in the water. Therefore, it can be concluded that this treatment plant has some environmental implications due to high COD, TSS, DO, and nitrate levels. Further analysis of each step of the wastewater treatment plant is needed to thoroughly understand the causes of variations in the water quality parameters.
Computer vision-based approach to floating waste detection
(Faculty of Science, University of Kelaniya Sri Lanka, 2024) Rathsara, K. M. A. C. D.; Sandaruwan, K. D.
Water pollution, especially from floating waste like plastics, metals, and organic matter, poses a severe threat to aquatic ecosystems and environmental health. This study aims to develop a computer visionbased model for detecting floating waste in water bodies, utilizing recent advancements in deep learning to enhance detection accuracy and efficiency. This paper presents a study toward the development and implementation of the You Only Look Once model (YOLOv8n) to improve accuracy and efficiency in detecting floating waste. The primary objective is to develop a better model for the detection of various floating waste of concern, including glass, metal, plastic, and water hyacinth. The Research involves collecting datasets from publicly available sources as well as web scraping to collect additional images. After data collection, several preprocessing steps were applied, including cleaning and normalization to ensure consistency across the dataset. Data augmentation techniques were used to increase the diversity of images and improve model reliability. Finally, the dataset was labeled using annotation tools. The YOLOv8n model was trained on this dataset with iterative parameter optimization and various experiments to improve detection performance. Experiments included creating a model from scratch, fine-tuning it, using a pre-trained model, and transferring weights to new configurations. The experiments demonstrate that the YOLOv8n model is highly effective for detecting floating waste. The model achieved a mean average precision (mAP50) of 0.932, with a precision of 0.904 and recall of 0.852, indicating strong accuracy in detection. The YOLOv8n model has shown exceptional performance, particularly in detecting water hyacinth, highlighting its effectiveness and efficiency in floating waste detection. Moreover, the model has the ability to detect floating waste precisely and potentially can also be used in real-time applications for monitoring the water environment. These findings have a huge potential for real-world applications involving rapid responses in aquatic environments and further conservation. Future work will focus on further training with iterative adjustments and dataset augmentation to improve the adaptability and accuracy of the model across different water conditions. This includes expanding the dataset through additional data collection efforts and increasing the diversity and number of identification classes. This study contributes to the wider discourse of environmental conservation by calling for innovation in technological solutions to reduce the adverse effects of floating waste in aquatic environments and also promotes sustainable management of water resources.
Wireless pager system for enhancing emergency communication in hospital environment
(Faculty of Science, University of Kelaniya Sri Lanka, 2024) Gunarathna, T. G. L.; Adhikari, A. M. N. D. S.; Bandara, K. D. Y.; Gunawardana, K. D. B. H.; Seneviratne, J. A.; Perera, M. H. M. T. S.
Maintaining fast and efficient communication between hospital staff is critical to ensure patient safety during emergencies. However, challenges such as the lack of Global System for Mobile Communications (GSM) signals in countries like Sri Lanka and the risk of using cable communication during hazardous weather conditions further complicate emergency communication. This paper proposes a wireless pager system utilizing LoRa (Long Range) technology to facilitate seamless interaction between doctors, nurses, and other supportive and administrative staff in a hospital. LoRa operates on sub-gigahertz frequencies, providing robust signal penetration and extended range, making it ideal for hospital environments where walls and infrastructure often disrupt traditional signals. The proposed system consists of three primary modules: the Ward Module, Central Hub, and Doctor Module. The Ward Module, placed in hospital wards, allows nurses to trigger emergency alerts by selecting an available doctor. It also provides status updates on message delivery and doctors' responses. The Central Hub acts as the system's control center, maintaining a database of doctors and wards, managing doctor availability, registering new entries, and logging communication transactions. It utilizes a web-based application to handle and collect data, which runs on the Central Hub, streamlining data management and access. The Hub also backs up data to the cloud and stores it locally during internet outages, synchronizing once the connection is restored. The Doctor Modules enable doctors to log their presence by selecting their ID from a list obtained from the Central Hub. This login data is updated in the Central Hub and shared with the Ward Modules. Upon receiving an emergency alert, doctors can respond by accepting, canceling, or forwarding the message, with the updated status being communicated back to the Ward Module. The system was tested in a simulated hospital environment using two Ward Modules, two Doctor Modules, and a Central Hub, covering a 200m distance. Both the Ward and Doctor Modules were built using ESP32 microcontrollers with LoRa modules operating at 433 MHz, while the Central Hub was developed using a Raspberry Pi single board computer with a LoRa module. The system demonstrated reliable performance, maintaining stable communication across the test range. It also demonstrated potential for larger hospitals, with extended range possible through proper antenna configuration. A 96% success rate was recorded, with message transmission in under 2 seconds. While LoRa offers robust long-range communication with low power use, its limited bandwidth poses challenges for large data transmission. However, for emergency pager systems, the trade-off between power efficiency and data capacity is acceptable. The system operates independently of traditional communication infrastructure, providing hospitals with a sustainable and resilient solution for emergency communication. It streamlines emergency response in hospital wards by enabling realtime communication and status updates between staff, ensuring fast and accurate transmission of critical information. This enhances the efficiency of interventions and improves patient care outcomes.
Allelopathic effects of aqueous extract of invasive alien cactus on seed germination and seedling growth of an invasive alien legume – Leucaena leucocephala
(Faculty of Science, University of Kelaniya Sri Lanka, 2024) Sandamini, O. V. P. H. N.; Ratnayake, R. M. C. S
One impact of Alien invasive plants (AIP) on the ecosystems is allelopathy. The allelopathic activity of the aqueous extract of an AIP, Opuntia stricta on seed germination and seedling growth of Leucaena leucocephala (AIP) were studied in this research. Selection of these two AIP based control of AIP by utilization. A concentration series of 10, 25, 50, and 75 g L-1 O. stricta was tested with distilled water as the control to assess seed germination percentages, mean shoot lengths and mean root lengths of L. leucocephala. The viability of the L. leucocephala seed lots were 80%. A pot experiment was conducted to investigate the seedling growth performance of L. leucocephala. All the data were subjected to the One-way ANOVA test at p ≤ 0.05 followed by Tukey pairwise comparison using the “R” software. The highest and lowest germination percentages were recorded in control (60.0 ± 2.9) and 50 g L-1 treatment (43.3 ± 1.6) respectively after four weeks. Seed germination percentages of L. leucocephala were decreased under the different concentrations of O. stricta extract compared to the control. However, the difference was not significant (One-way ANOVA, p ≤ 0.05). The lowest mean shoot (37.6 ± 3.5 cm) and root (11.3 ± 0.3 cm) lengths of L. leucocephala were observed at 50 g L-1 concentration after 12 weeks. There was no significant difference among the shoot length of L. leucocephala plants in all treatments. There was a significant difference in the mean root length of L. leucocephala plants between 10 and 75 g L-1 treatments. The highest mean shoot (49.7 ± 1.9 cm) and root (13.5 ± 0.8 cm) lengths were observed at 75 g L-1 concentration indicating allelochemicals enhanced the seedling growth of L. leucocephala. The 75 g L-1 concentration showed a fertilizer effect by increases in the mean shoot length and mean root length of L. leucocephala. As an AIP, L. leucocephala may also possess allelopathic compounds of its own, which could interact with those of allelochemicals in O. stricta extracts and neutralized the allopathy. Therefore, the growth performance of L. leucocephala was enhanced. The findings of the study provide novel knowledge and understanding of the competitive nature of both AIP studied in relation to their allelopathy.
Interactions between penicillin and aqueous extracts of Plectranthus amboinicus and Plectranthus zeylanicus against Staphylococcus aureus.
(Faculty of Science, University of Kelaniya Sri Lanka, 2024) Hafsa, M. F. F.; Darshana, D.; Wickramasinghe, S. S.; Tennakoon, S. H.; Napagoda, M. T.
Penicillin, the pioneering antibiotic, has declined in effectiveness against Staphylococcus aureus due to increasing resistance, highlighting the urgent need for alternative strategies. Combining penicillin with medicinal plant extracts, such as Plectranthus amboinicus (Kapparawalliya) and Plectranthus zeylanicus (Iriveriya), rich in antibacterial compounds, offers a promising approach to revitalising its therapeutic efficacy. This study aimed to evaluate the potential interactions between penicillin and the aqueous extracts from P. amboinicus (PA) and P. zeylanicus (PZ) against both Methicillin-sensitive S. aureus (MSSA) and Methicillin-resistant S. aureus (MRSA). Whole plants of PA and PZ were macerated in distilled water for 24 hours at room temperature to prepare aqueous extracts. In the preliminary screening, the antibacterial activity of the aqueous extracts (500 mg/mL), and penicillin (3 mg/mL) were evaluated individually using the well-diffusion method. Ciprofloxacin (2 mg/mL) and distilled water were used as positive and negative controls, respectively. Subsequently, the minimum inhibitory concentration (MIC) of penicillin against MSSA and MRSA was determined using the broth microdilution method, followed by subculturing to determine minimum bactericidal concentrations (MBC). Aqueous extracts of PA and PZ were combined with different penicillin concentrations (2×MIC, MIC, 1/2×MIC, 1/4×MIC). The antibacterial activity of these combinations against MSSA and MRSA was evaluated using the well-diffusion method (well-diameter = 6 mm), measuring the inhibition zone diameter (IZD). The IZD of MIC of penicillin was compared with the IZD of penicillinPA and penicillin-PZ combinations to determine the interactions. Results showed that the aqueous extracts of PA and PZ did not demonstrate inhibition zones against MSSA and MRSA. The MIC and MBC of penicillin against MSSA were determined as 0.052 µg/mL and 100 µg/mL, respectively. However, the MIC of penicillin against MRSA was indeterminable, with an MBC exceeding 100 µg/mL. Notably, most combinations of penicillin with PA and PZ exhibited significantly higher IZD compared to MIC of penicillin alone (no inhibition zones), against both MSSA and MRSA (p < 0.05). Among all the combinations, the highest IZD was observed with the MIC+PZ combination against both MSSA and MRSA (IZD = 12.78 mm and 11.89 mm respectively). Potentiation was observed for the penicillin-PA combination, at penicillin concentration corresponding to the MIC against MSSA and at MIC, 1/2×MIC, 1/4×MIC against MRSA. With PZ, potentiation against MSSA and MRSA occurred at a penicillin concentration equivalent to the MIC. Additionally, penicillin combined with PZ demonstrated significantly stronger potentiation (p < 0.05) compared to penicillin-PA combinations, at equal penicillin concentrations, against both strains. In conclusion, the aqueous extracts from PA and PZ potentiated the antibacterial effectiveness of penicillin against MSSA and MRSA. This underscores the promise of these combinations for potent antibacterial therapies, suggesting a potential avenue for repurposing and reintroducing penicillin in combination with plant extracts to address antibiotic resistance. Further research should focus on understanding the mechanisms that enhance the effectiveness of penicillin when combined with PA and PZ.
Assessment of derivative spectrophotometry for analyzing competitive adsorption of brilliant green and methylene blue using multiple coated graphite oxide/sand composite
(Faculty of Science, University of Kelaniya Sri Lanka, 2024) Sakalasuriya, D. D.; Perera, P. L. R. A.; Perera, W. P. R. T.; Sakunthala, K. A. D. D.; Premaratne, W. A. P. J.; Liyanage, J. A
Wastewater from industrial sectors such as paint production and textile processing are often contaminated with multiple dye pollutants. The simultaneous presence of multiple dyes like Brilliant Green (BG) and Methylene Blue (MB) poses significant challenges for treatment technologies. These dyes not only contribute to environmental degradation but also pose significant health risks, including allergic reactions and cancer due to their toxicity and persistence in ecosystems. A major challenge in treating dye mixtures is the accurate identification and quantification of multiple dyes due to overlapping absorption spectra. This research aims to enhance the resolution of spectral data using derivative spectrophotometry, enabling more distinct identification of overlapping dye components. In this study, the competitive adsorption of MB and BG onto multiple coated graphite oxide/sand (MGO/S) composite was examined. The determination of dye concentrations was carried out using first order derivative (1D) spectrophotometry. Kinetic and isotherm evaluations were conducted under optimal conditions: pH 7.0, 0.09 g of M-GO/S, and a contact time of 20 minutes in binary dye systems. The 20-minute contact time was sufficient to reach equilibrium, as extended durations showed no significant change in adsorption results from preliminary experiments. The experiment was triplicated. The equilibrium adsorption of MB and BG dyes onto M-GO/S showed an inverse relationship with their initial concentrations, signifying the competitive adsorption dynamics where the dyes compete for the available adsorption sites. In a binary mixture of 10 mg/L BG and MB, significant peak overlap at 625 nm and 664 nm hinders precise concentration measurement using zero-order spectra. First-order derivative spectrophotometry resolves this by identifying the adsorption peaks of MB at 625.6, and 503 nm, and BG at 443.2, 445.6, 525.6 and 664.2 nm. Simultaneous determination of BG and MB was achieved at 443.2 nm (1D443.2) (R2=0.9982) and 625.6 nm (1D625.6) (R2=0.9958), respectively. The characteristic parameters of regression equation for the 1D method and obtained coefficient of determination for individual BG and MB were also studied. Therefore, the application of derivative spectrophotometry has proven to be an effective method for quantification of simultaneous adsorptions of BG and MB onto multiple coated graphite oxide adsorbent. This technique allows for precise differentiation and quantification of each dye in the presence of the other, enhancing the understanding of their adsorption dynamics. The results demonstrate that derivative spectrophotometry can improve the accuracy and efficiency of multipollutant adsorption studies.
Factors associated with bedtime procrastination among undergraduates of a selected higher educational institute in Sri Lanka: a cross-sectional study
(Faculty of Science, University of Kelaniya Sri Lanka, 2024) De Silva, K. U. S.; Samarakoon, N.; Rathnapala, J.
Bedtime procrastination can negatively impact one’s life in different ways, including learning, concentration, memory, stress, irascibility, obesity, diabetes, stroke, hypertension, working inefficiency, and a reduction in life satisfaction. In order to lead a balanced, fulfilling, and productive life, it is important to establish and maintain a proper sleeping schedule. Procrastinating bedtime is an irritating and problematic trait that is witnessed in a multitude of cultures and is highly prevalent among university students throughout the world. Also, there is less evidence on demonstrating factors associated with bedtime procrastination of university students in the Sri Lankan context. The present study aimed to investigate the factors associated with bedtime procrastination among undergraduates at a selected higher educational institute in Sri Lanka. The descriptive cross-sectional study was conducted among 335 undergraduates of KAATSU International University (KIU) in Sri Lanka using the Simple Random Sampling method. It was completed within the time period from January 2023 to January 2024. Ethical approval was obtained from the Ethics Review Committee at KIU. A self-administered questionnaire was used to collect the data, and the questionnaires were distributed among the participants by physically reaching them. The nine-item Bedtime Procrastination Scale (BPS) was utilized to assess bedtime procrastination, and a demographic questionnaire was utilized to assess the demographic factors among the undergraduates at KIU. The data were analysed using the One Way ANOVA using IBM SPSS version 25. The variables; ‘gender’, ‘academic year’ and ‘degree categories’ have not shown any statistically significant differences (p>0.05; One Way ANOVA). Yet according to the test results, it revealed that ‘employment status’ has shown statistically significant differences. (F= (2,332) = -4.251, p = 0.015). A Turkey post hoc test revealed that the bedtime procrastination varied among the employment status was statistically significantly lower in-unemployed (27.82 ± 5.3, p = 0.022) and self-employed (23.4 ± 3.2, p = 0.011) compared with employed (25.98 ± 5.0). However, there was no statistically significant difference between the unemployed and self-employed groups (p = 0.090). The present study concluded that there is an association between the employment status of undergraduates at KIU and their bedtime procrastination, along with university students who procrastinate at bedtime are more likely to be employed. Further research studies to develop interventions to minimize university students in Sri Lanka from procrastinating at night before going to bed is recommended.
Mathematical modeling of diabetes mellitus
(Faculty of Science, University of Kelaniya Sri Lanka, 2024) Subawickrama, H. D. K. M.; Munasinghe, J.; De Silva, T. M. M.
Diabetes is becoming a silent epidemic that is endangering public health worldwide. For instance, the majority of the 422 million diabetics globally reside in low- and middle-income nations, and the illness directly causes 1.5 million fatalities per year. In recent decades, the prevalence and complexity of the chronic medical condition diabetes have raised serious concerns about global health. As a result, studying and developing mathematical models becomes increasingly important since they provide an advanced perspective for realizing the complex nature of the disease and creating realistic care with preventive measures. Furthermore, it is a useful tool for tracking the rising incidence of the disease and creating affordable control measures for both its incidence and consequences. Thus, the main focus of this study is to propose a mathematical model that is employed to forecast changes in the prevalence of diabetes using a saturated incidence rate, which reflects a diminishing rate of new infections as the number of affected individuals increases, by extending the Diabetes Complication (DC) and Susceptible Diabetes Complication (SDC) models. It has been established which factors lead to both endemic and disease-free equilibriums. The conditions that contribute to the equilibrium between endemic and disease-free states are identified. Based on the eigenvalues of the Jacobian matrix, the local stability of the equilibrium points has been determined. Since diabetes is not a transmissible disease, there is no disease-free equilibrium and when the constant term 𝑅0 < 1, the endemic equilibrium point is locally asymptotically stable. Additionally, the Lyapunov function theory has been utilized to study global stability. We observe the effect of the term saturated incidence rate under some parameter conditions. Based on data gathered from annual mortality reports and health bulletins that have been published by the Ministry of Health, Sri Lanka and the United Nations’ World Population Prospects the parameters for complications related mortality rate, the natural mortality rate, and the birth rate are estimated. Numerical simulations using MATLAB’s ODE 45 technique are conducted to validate the analytical findings of the proposed model and assess its approach. This model also monitors the number of susceptible people as well as the population with and without diabetes complications. We predict that the 2.29 million will be the approximate Sri Lankan total prevalence of diabetes in 2024 and additionally, it notes an average annual increase of about 0.2199% in diabetes prevalence. The model’s accuracy is highlighted by its minimal average relative error, making it effective for forecasting and valuable for informing disease management strategies.
An automated approach to female body-type classification for fashion style recommendations using computer-vision and machine learning
(Faculty of Science, University of Kelaniya Sri Lanka, 2024) Navodya, H. K. S.; Sandaruwan, K. D.
This research explores a computer vision-based approach to automating female body-type classification with the goal of enhancing personalized fashion recommendations in the online retail industry. By tailoring style suggestions to individual body types, the system aims to improve customer satisfaction and reduce return rates. The system utilizes deep learning techniques to analyze full-body images and classify them into five body-types: apple, inverted triangle, hourglass, pear, and rectangle. Traditional body-type classification methods often require detailed body measurements or complex 3D modeling, posing challenges in terms of user-friendliness and accessibility. This study highlights the advantages of deep learning and transfer learning, which enable the extraction of complex features from images, facilitating accurate and efficient classification without requiring specialized hardware or extensive user input. The model was trained using a dataset of 560 full-body images of female participants aged 20 to 35 years, representing a young adult demographic. To identify the most effective model for this task, the research compared the performance of various machine learning algorithms, including machine learning models, deep learning CNN architectures, and transfer learning models such as Xception, ResNet50, MobileNetV2, and VGG16. Accuracy and model stability were the primary evaluation criteria. The VGG16 model emerged as the best-performing classifier, achieving an accuracy rate of 83.50%. It was trained on 224x224x3 images over 100 epochs with a batch size of 32, using the Adam optimizer and a learning rate of 1e-5. Categorical cross-entropy was used to measure model performance, ensuring optimal parameter adjustments. This model was integrated into both a mobile application, and a web application. These applications allow users to upload images, predict their bodytype, and receive personalized fashion suggestions. In addition to performance metrics like precision, recall, F1-score, and accuracy, the system was validated through a user feedback survey. This survey gathered responses from users who interacted with the web application and served as a human validation metric. The classification model demonstrated performance, particularly with high F1-scores for the Inverted Triangle (0.91) and Apple Shape (0.82) body types. Hourglass and Pear shapes, while moderately accurate, showed lower precision and recall. User feedback from 60 respondents indicated high satisfaction with the system: 94% expressed satisfaction with the classification accuracy, 85.5% emphasized the importance of body type in fashion selection, and 73% reported satisfaction with the personalized fashion suggestions. These insights confirm the system's reliability in real-world applications. While this research demonstrates satisfactory results, limitations exist. The utilized dataset is relatively small, and the classification is limited to five body-types. Additionally, the fashion suggestions are text-based rather than image-based. Future work will focus on expanding the dataset to improve classification accuracy, incorporating all eight recognized female body types, and integrating image-based fashion suggestions to enhance usability. This research lays the foundation for future advancements in AI-driven fashion recommendation systems, contributing to a more personalized, and efficient fashion retail experience.
Intracellular peloton colonization and mycorrhizal associations in epiphytic orchid roots
(Faculty of Science, University of Kelaniya Sri Lanka, 2024) Disanayaka, D. M. H. A.; Thathsarani, Y. K. D. D.; Edirisinghe, P.; Senanayake, S. P.
Orchids are highly valued for their esthetic beauty and economic significance, playing a vital role in the global floriculture industry. In their natural habitats, orchids heavily depend on mycorrhizal associations, which influence seed germination, protocorm growth, and nutrition. Despite their importance, understanding these associations remains a challenge. In Sri Lanka, there is limited knowledge exists on the root-associated fungal species interacting with epiphytic orchids and their ecological roles. Exploring the endophytic fungal microbiome in these orchids helps in identifying fungi that form mycorrhizae in epiphytic habitats, paving the way for effective cultivation and developing novel conservation strategies. Intracellular entangled hyphal coils that colonize within the cortex of the roots of epiphytic orchids are known as pelotons. Knowledge of the presence and the distribution of pelotons is crucial for understanding the symbiotic relationships between orchids and mycorrhizal fungi. Therefore, the objective of this study was to investigate the distribution of pelotons in the roots of selected epiphytic orchids. In the present study, sixteen wild-grown and cultivated epiphytic orchid roots belonging to genera, i.e. Dendrobium, Arachnis, and Vanilla were randomly collected from four study sites in tropical lowland, wet and intermediate zones in Sri Lanka. Microscopic imaging of microtome sections was employed to observe the peloton colonization within the randomly sampled orchid roots. Longitudinal and cross-sectional analyses of six orchid root samples revealed sparse colonization of fungal hyphae. Extensive peloton colonization was observed only in the roots of two specimens of Dendrobium sp. and in one specimen of each Arachnis sp. and Vanilla sp. indicating the presence of mycorrhizal fungi in the roots. However, peloton colonization was not found in all the sampled roots of the studied genera. Furthermore, microscopic observations showed that intracellular pelotons were predominantly colonized in the cortex at approximately two centimeters beyond the tip of the roots that are adhered to the substrate. Pelotons were observed as thin hyphal masses ranging from circular and irregular to elongated shapes with hyphae often knotted or spiraled in various dimensions. The study highlighted that wild Dendrobium sp. from Avissawella, Western province, exhibited the highest peloton colonization (5–6 per root cortical cell) with both circular and elongated shapes. In contrast, Arachnis sp. had one irregularly shaped peloton per root cortical cell. Dendrobium sp. from Mahawa, Northwestern province showed both circular and irregular pelotons while Vanilla sp. from Kelaniya, Western province displayed the lowest colonization with irregular pelotons. Irregularshaped pelotons are predominantly found except in Dendrobium sp. from Mahawa, Northwestern province underscoring geographic and genus-specific influences on peloton morphology. These findings enhance the understanding of mycorrhizal associations in orchids and provide valuable information for future research on orchid-mycorrhizal symbioses and their ecological significance.
Change detection of vegetation cover in Kurunegala district by using remote sensing approach
(Faculty of Science, University of Kelaniya Sri Lanka, 2024) Imbulana, I. B. A. C.; Jayasinghe, V. S.; Peramune, P. R. S. N.; Samaraweera, S. A. P. T.; Weerasinghe, V. P. A
The amount of vegetation cover has reduced over time due to the rapid increase in population, expansion and intensification of agricultural activities, and unsustainable use of resources worldwide. This leads to significant negative impacts on the ecosystems. Although several studies have been carried out on vegetation change in Sri Lanka, there is little or no information available in Kurunegala District. Therefore, the objective of the present study was to assess the extent of changes in areas with healthy vegetation cover in Kurunegala District of Sri Lanka, through examining the Normalized Vegetation Index (NDVI) over a period of 10 years from 2013 to 2023. NDVI was employed to determine the growth condition of vegetation. Remote sensing data from Landsat-8 OLI/TIRS images were used to perform NDVI analysis. The area was classified into no vegetation and vegetation and the values above 0.3 were considered as the vegetation. The obtained NDVI maps were reclassified, and the resulting maps were converted to vector maps. The final values were used to compute the area under no vegetation and vegetation. The results of the present study indicated a significant vegetation cover change between 2013 and 2023. The results revealed a conversion of 1424.95 km2 area from no vegetation to vegetation and a conversion of 550.57 km2 area from vegetation to no vegetation. In addition, 669.98 km2 of no vegetation area and 2253.35 km2 of vegetation area have remained unchanged. The vegetation area, which was initially 2804.32 km2 in 2013, had expanded to 3678.79 km2 in 2023, reflecting a 31.18% transformation of no vegetation areas to vegetation areas. Thus, it can be concluded that the vegetation cover area in the year 2023 had increased compared to 2013. However, NDVI does not differentiate between various types of vegetation, such as agricultural crops and forests, which is a limitation of this study. Enhancing sustainable land management, strengthening environmental policies, promoting community involvement and continuous monitoring are crucial for further expansion of the vegetation cover in Kurunegala District
A simulation framework for investigating the market scenarios of the forex market using Ornstein-Uhlenbeck and Monte-Carlo simulation
(Faculty of Science, University of Kelaniya Sri Lanka, 2024) Kaushalya, H. A. T.; Liyanage, U. P.
The forex market is a financial market that is a global marketplace for exchanging national currencies. Forex investment is generally mediated by a broker and executed by a trader. Thereby, the investment scenarios are based on realistic exchange price fluctuations and the best market representations. Herein, all possible combinations of upward-downward movement of the exchange rate fluctuations have been considered as scenarios. However, the exchange rates have three parts namely, selling price, buying price, and absolute exchange rate, making the framework rather complex. The three price series have to be simulated focusing on the market behaviors and particular exchange rate patterns alongside price regulations undertaken by the respective authorities. As the literature suggests, in such a scenario modeling, the currency historical data analysis may not be prominent as the currency profiles have less memory dependency. Thus, in the determination of possible scenarios, memory-less stochastic processes are more appropriate than memory-depending stochastic processes. This study investigated the possibility of forming such a realistic simulation framework using appropriate mathematical tools. The exchange rates of currencies are highly volatile. The literature has illustrated that the OrnsteinUhlenbeck (OU) process shows a reliable representation of such exchange rate profiles. Thereby, this analysis focused on OU simulation representing the exchange of major nine currency pairs. The respective OU process parameters were identified based on historical data. However, parameter optimization was conducted at the level of stochastic process expectation. Thus, the Monte Carlo procedure is used in parameter estimation and has been utilized in scenario analysis as well. The respective realizations of these identified OU processes have been utilized in modeling the possible exchange rate representations and scenario simulations. As an example, the three series of USD-EURO exchange rates are simulated by the OU process with the identified parameters based on their respective historical data. A Monte-Carlo is used to formed to analyze desired strategies alongside the perspectives of brokers and traders. Using the simulation framework, we have tested the price fluctuations for traders and brokers to ensure they are realistic based on exchange rate data. The results have illustrated that brokers get the optimum profit. The profit of each process has been calculated for the broker, and the expected profit has also been calculated. Not only that, changing the parameters (mean and volatility) from 0.0001 to 0.0006 also got the expected values to check how the profits vary in that situation. After each process space was stable, identified strategies to get more profit from the broker's perspective. Finally, the strategies from the trader’s perspective were identified to get more profit while assuming there was only one trader. Also, the same process was done 1000 times and got traders an expected profit. Through the application of simulation tools, this research contributes to the current discussion about successful trading tactics in this changing environment.
Effect of organic amendments for growth enhancement of ornamental cactus: Mammillaria prolifera (P. Mill.)
(Faculty of Science, University of Kelaniya Sri Lanka, 2024) Ranathunga, R. M. T. K.; Ratnayake, R. M. C. S.
Cactus is a popular group of house plants in the world due to their attractive morphology. Among the ornamental cacti, Mammillaria prolifera (P. Mill.) is widely cultivated in different geographical regions of the world. Chemical fertilizers are excessively applied in cacti nurseries and their toxic traces such as arsenic, chromium, cadmium, and mercury accumulate in water resources and soil causing environmental pollution. This study aimed to evaluate the effect of a novel organic liquid fertilizer (OLF) to enhance the growth of M. prolifera, as a substitute for chemical fertilizers. The OLF was prepared by aerobically digesting a mixture of Tithonia diversifolia leaves, coconut husk ash, rock phosphate, and dried cow dung in 6.0 L of water for six weeks. 5%, 15%, and 25% OLF concentrations were used as the OLF treatments along with “Lonzin” as the chemical liquid fertilizer (CLF). Samesized M. prolifera stems were transplanted in 10 cm diameter pots filled with a cactus growth medium prepared by mixing coarse sand, sand, and compost. After one month of growing, M. prolifera plants were randomly assigned to OLF treatments and CLF treatment with 15 replicates. Treated plants were placed in a plant house at 27 0C temperature and 60% relative humidity. All the treatments were applied once a week for six months. After six months of the experiment, the height and width of the mother stem, number of phylloclades, number of flowers, time for first flowering, and root length were measured. Data were analyzed using, analyzed by one-way ANOVA at α = 0.05 and Turkey pairwise comparison test using “R” software (version 4.2.2). Plants treated with 5% OLF showed significantly better growth metrics including mean height (6.760 ± 0.942 cm), width (2.013 ± 0.344 cm), number of phylloclades (12.33 ± 5.1) number of flowers (2.07 ± 0.99) and root length (7.061 ± 1.24 cm) while no significant differences were observed between the 15% OLF, 25% OLF, and CLF treatments. M. prolifera plants treated with 25% OLF recorded the lowest mean duration (15.3 ± 4.2 weeks) for the first flower formation due to the appropriate nutrient content for flowering. Based on the growth performance data, 5% OLF treatment significantly enhanced the growth of M. Prolifera plants. Hence, 5% OLF concentration can be considered as the optimum concentration for the growth enhancement of M. prolifera cactus.
Antifungal activity of chitosan-plant extract-based coating for crown rot disease in banana (cv. Embul)
(Faculty of Science, University of Kelaniya Sri Lanka, 2024) Piyumali, W. M. D. T.; Gunaratna, A. G. M. J.; Kodituwakku, T. D.
Proper postharvest handling is essential to reduce postharvest losses and maintain the quality of fresh produce. Banana crown rot, which is caused mainly by Colletotrichum musae and Fusarium poliferatum is one of the most economically significant diseases affecting banana fruits. It impacts both the yield and marketability of bananas. Fungal infection occurs through the cut surface of crown tissues of dehanded banana. Symptom development initiates as a blackening of crown tissues which later advances down the fruit stalks. Fungal control methods often rely on synthetic fungicides and may cause environmental and health concerns due to their toxicity. Thus, this study was planned to develop an eco-friendly alternative to chemical fungicides to control banana crown rot disease. This research investigated the potential of soursop (Annona muricata) pulp extract in combination with chitosan as a natural antifungal coating to inhibit the growth of C. musae and F. poliferatum in banana (cv. Embul). In the initial stages of the study, soursop pulp oil was extracted using a Soxhlet apparatus. The solvent was evaporated using a rotary evaporator and freeze-dried. Fruit coating was prepared using chitosan, glycerol, Tween 80 and soursop pulp. A range of pulp oil concentrations were tested including 2.5%, 5.0%, 7.5% and 10% combined with chitosan (1%). The food poisoning technique was used to test the antifungal activity of the fruit coating using One-way ANOVA and Tukey’s pair-wise comparison tests. Mancozeb was used as positive control and DMSO was used as negative control for antifungal assay. A significant difference in antifungal activity was observed among several concentrations of peel and pulp coating solutions (p < 0.05). For In vivo application C. musae inoculated Embul banana were treated with pulp coating, fungicide and distilled water as control. The impact of the treatments was assessed by measuring the percentage weight loss, fruit firmness, total soluble solids (TSS), titratable acidity (TA) and pH values. Complete inhibition of the pathogen (in vitro) was observed at both pulp and peel extract concentrations of 7.5% and above for both fungal species. The minimum inhibitory concentration (MIC) for C. musae and F. poliferatum was considered to be 7.5%. The minimum lethal concentration (MLC) was 10%, at which no mycelial growth was noted in the growth revival test. In vivo, pulp extract coating showed significant inhibition of C. musae compared to the control. Kruskal – Wallis test showed a statistically significant difference in disease severity among the treatment groups (H = 6.77, p = 0.034) with the coating applied group showing lowest disease severity. Previous research findings revealed that chitosan possesses antifungal activity. The combined antifungal efficacy of chitosan and A. muricata extracts inhibits fungal growth and these findings suggest that the developed fruit coating has the potential to be an effective strategy for mitigating crown rot in bananas caused by C. musae and F. poliferatum.
Comparative desorption efficiency of Cd(II) and Pb(II) from used plasma-functionalized coconut coir biochar
(Faculty of Science, University of Kelaniya Sri Lanka, 2024) De Alwis, B.; Rathnayake, I.; Munaweera, I.; Perera, A. D. L. C.; Jayasinghe, S.
This study investigates the desorption of Cadmium (Cd(II)) and Lead (Pb(II)) ions from used plasmafunctionalized coconut coir biochar (PBC), a process crucial for wastewater treatment. The improper disposal of used adsorbents laden with Cd(II) and Pb(II) contributes to environmental pollution, making this research significant. Coconut coir biochar (BC) was prepared using coconut coir dust via pyrolysis at 500 °C for 3 h under controlled N2 environment. The BC was subjected to atmospheric air plasma treatment (AAPT) for 30 min to produce PBC. Both BC and PBC were characterized using Fourier Transform Infrared Spectroscopy (FTIR), point of zero charge (pHPZC), methylene blue (MB) and iodine number, moisture and ash content. The quantitative analysis was performed using a flame atomic absorption spectrometer (FAAS). At pH 7, PBC adsorbs 130.00 mg g-1 of Cd(II) from a 250 ppm solution, and at pH 5, it adsorbs 80.97 mg g-1 of Pb(II) from a 500 ppm solution within 1 minute. In comparison, BC shows lower adsorption capacities of 96.00 mg g-1for Cd(II) and 50.01 mg g-1for Pb(II) under the same conditions. Desorption experiments were conducted using 25.0 mg of Cd(II) and Pb(II) adsorbed BC and PBC, which were shaken with HNO3 as the desorbing agent at 30 °C. The pH and contact time were optimized to evaluate the maximum desorption capacity of both BC and PBC. The maximum desorption capacity of Pb(II) for PBC was 73.80 mg g-1 within a contact time of 15-minute and for Cd(II), it was 8.91 mg g-1 under the optimum conditions of pH 1 and 1-minute contact time. For BC maximum desorption capacity of Pb(II) was 47.63 mg g-1 with a 30-minute contact time and for Cd(II), it was 8.54 mg g-1 under the pH 1 and 1-minute contact time. The desorption percentage from the adsorbed amount was 91.14% for Pb(II) and 6.85% for Cd(II) for PBC. For BC, it was 95.24% for Pb(II) and 8.83% for Cd(II). These results highlight the potential of PBC as an efficient adsorbent for the remediation of Pb(II) and Cd(II) in wastewater, demonstrating high efficiency in Pb(II) desorption but limited efficiency in Cd(II) desorption.
Educational background of the child abuse convicts in Sri Lanka
(Faculty of Science, University of Kelaniya Sri Lanka, 2024) Subasinghe, W.; Ihalagama, S.
Child abuse is one of the most violent incidents in Sri Lanka. There are nearly 10000 reported child abuse cases in 2023. There is a new trend of criminal offences against persons related to child abuse in Sri Lanka. The study was focused on exploring the child abuse perpetrators’ social background and education access in childhood. Research Problem was ‘what is the social background to get less education of child abuse perpetrators’. research question was, ‘is there a relationship between less education opportunities and committing child abuses in Sri Lanka?’. research objective was to explore the relationship between opportunities for education and committing child abuse among convicts. The research adopted an ontological approach to subjectivism and an epistemological approach of interpretivism. It was descriptive, cross-sectional, and qualitative. The study was underpinned in cognitive theory introduced by Charles Goring focused on the differences on addressing education towards crime. Ten convicted persons have been interviewed. Thematic analysis was used for the analysis. Child abuse can happen with one's own child abuse, close relatives' child abuse, neighbor child abuse, and stranger child abuse. Several risk factor characteristics of child abuse perpetrators could be identified. It could be summarized as perpetrators’ childhood experience, social interrelationships, less opportunities and encouragements to get education, less economic background, and lack of awareness about the child abuse law in the community, etc. Family background was important in determining the risk of becoming a child abuser and was intertwined with economic factors and issues related to sexual behaviour. Poor childcare and parent care relationships, frustration, socioeconomic conditions, and alcoholism are other main factors behind this behaviour. Most of them grew up not with their mothers but with close relatives such as grandparents, aunts, etc. Most of these people had only attended school up to a maximum grade eight. Many of them cannot read and write, they had associated with older people, not peers at their school age, they had been addicted to use illicit alcohol and to watch nude pictures. There were also people who had developed sexual relationships with girls of fourteen or fifteen years of age and brought them to their homes. But they didn't know or had ignored that one day they would be punished by the law. Most of the abusers had done wage labor as their occupation in paddy work and other unskilled works. Many of these abusers had failed in marriages with divorces or separations. The social background of abused children was also in an unsafe condition. 13 years of school education access must be compulsory and government attention should be enhanced to mitigate the issue
The role of Solenopsis geminata in affecting health and routine activities: A case study of undergraduate students at Eastern University, Sri Lanka
(Faculty of Science, University of Kelaniya Sri Lanka, 2024) Gunarathna, S. M. D. P.; Vinobaba, M.; Udayakantha, W. S.
The tropical fire ant, Solenopsis geminata, is an invasive species that damages agriculture, infrastructure, and human health globally. In Sri Lanka, research is limited. This study examines the impact of Solenopsis geminata on undergraduate students’ health, daily activities, and campus experience at Eastern University. A structured interview-type questionnaire survey, using both closed and open-ended questions, was conducted to investigate details about allergic responses caused by S. geminata stings and other related issues experienced by undergraduate students at the Eastern University of Sri Lanka from July to December 2023. The questionnaire consisted of 20 questions in three major sections, demographics, sting incidents, and other related information. A randomly selected general undergraduate sample of 120 students participated in the questionnaire survey and were shown live samples and photographs of S. geminata for identification. Seventy-eight (n = 78) students who identified the species continued with the survey. Their ages ranged from 21 to 30 years old, with a maleto-female ratio of 4:5. In the group surveyed, 100% reported experiencing S. geminata stings. The most frequent symptoms were a combination of redness, itching, and swelling (51.7%), or just redness and itching (24.1%). Additionally, 13.79% exhibited oozing, and 5.2% developed long-term scars. According to Turkey's HSD, there is no correlation between the number of bites received and gender (p = 0.46), but a significant correlation was found between the average reaction to bites and age (p = 0.005). The survey also revealed that 10.34% reported damage to stored staples, 10.34% to crops, 11.2% to selling items, 8.6% to physical equipment, and 4.3% to seeds. These descriptive statistics highlight the significant impact of S. geminata stings on students' health and daily life, the economic damage to their stored staples, crops, and equipment. Future recommendations include increasing education on the prevention, urging the usage of biopesticides and management of S. geminata stings among students and implementing effective control measures to reduce the population of these ants.
Phytoplankton abundance and diversity in relation to water quality parameters: A study on Beira Lake and Ihalagama Lake in the Western Province in Sri Lanka
(Faculty of Science, University of Kelaniya Sri Lanka, 2024) Samaranayake, D. A. G. G. S.; Perera, H. A. C. C
Phytoplanktons are important components of the aquatic ecosystem. Diversity and abundance of the phytoplankton community of two urban lakes namely; Ihalagama Lake and Beira Lake were assessed in this study. The main aim of the present study is to investigate how the distribution of phytoplankton community is varied among two lakes and their relationship with water quality. Phytoplankton samples were collected from each sampling site from September 2023 to February 2024. Spatial variation of water quality parameters and phytoplankton diversity were assessed by one way ANOVA followed by Tukey’s pairwise comparison using MINITAB 17 software. A total of 20 phytoplankton species were recorded from both Beira Lake and Ihalagama Lake. They belong to six classes namely Class Bacillariophyceae, Class Chlorophyceae, Class Cyanophyceae, Class Zygnematophyceae, Class Euglenophyceae and Class Ulvophyceae. 16 phytoplankton species were identified from Ihalagama Lake, while 12 species were from Beira Lake. Microcystis aeruginosa is the most abundant phytoplankton species having 40% of relative abundance. Based on the results obtained from the Principal Component Analysis (PCA), Beira Lake was characterized by high abundance of Microcystis aeruginosa, Scenedesmus perforates, Pediastrum, Chlamydomonas, Rhizosolenia stolterfothii, Ulothrix, Lyngbya contorta, and Asterionella species. Ihalagama Lake was characterized by Navicula cryptocephala, Scenedesmus obliquus, Trachyneis aspera, and Stephanodiscus species. Total abundance is higher in the both sites of the Beira Lake than that of the Ihalagama Lake. The highest Shannon-Wiener diversity index (H) was recorded from Beira Lake (H = 1.124) while the highest species richness (SR) was recorded from Ihalagama Lake (SR = 1.046). Some water quality parameters including conductivity, secchi depth, NO3- concentration, PO43- concentration, COD, and BOD varied significantly between four sampling sites at 95% level of significance. The highest mean BOD level was recorded from the Beira Lake (7.30 mg/L) and the recorded lowest value was 2.46 mg/L, from the Ihalagama Lake. Similarly, the highest values for COD, nitrate and phosphate were recorded from the Beira Lake (633 mg/L, 1.73 mg/L, 1.07 mg/L respectively) while lowest COD, nitrate, and phosphate levels were recorded from Ihalagama lake (238.8 mg/L, 0.46 mg/L, 0.15 mg/L respectively). In terms of the two lakes combined, Beira Lake had higher than average levels of BOD, COD, and inorganic nutrients like phosphate and nitrate. On the other hand, Ihalagama Lake had lower than average levels of BOD, COD, nitrate, and phosphate, indicating that its water quality conditions are healthier and less contaminated. Therefore, it is suggested to identify the sources of pollutants and carry out continuous monitoring of water quality parameters, particularly in Beira Lake.