University of Sri Jayewardenepura: Journals & Proceedings
Not a member yet
5869 research outputs found
Sort by
Development and Characterization of Ready-To-Use Supplementary Food for Underweight Young Adults in Sri Lanka
No full textNutritional problems, especially being underweight, is a serious concern that impacts people of all ages and are made worse by contemporary economic unrest in Sri Lanka. Among every age, underweight young adults pose a critical concern and necessitate targeted intervention. Instant food items called "ready-to-use supplementary foods" (RUSF) are designed to treat mild malnutrition. This study aimed to develop a novel RUSF product specifically designed for underweight young adults in Sri Lanka. This research was conducted with preliminary sensory analysis, which included both hedonic rating test and a preference-ranking test, on a panel of 30 undergraduates. The optimal formulation was found to have a proximate composition of moisture, protein, crude fat, ash, and crude fiber content of 2.64±0.06%, 12.69±0.62%, 20.83±0.03%, 2.31±0.10%, and 2.07±0.10%, respectively, on a wet basis. The mineral content of calcium, iron, zinc, magnesium, and potassium was also assessed, with the results indicating levels of 1628.0±22.7, 2.3, 3.58±0.11, 413.62, and 527.30 mg per 100g of the product, respectively. The product's antioxidant activity was determined through ABTS and DPPH radical scavenging activity tests, yielding values of 12.13% and 13.94%, respectively. Furthermore, the peroxide level was negligible (0.667 mEq/Kg of fat) for the RUSF. Overall, the product boasts excellent acceptability, feasibility, nutritional value, and accessibility for the Sri Lankan young adults.
Keywords: Underweight, RUSF, Proximate analysis, Antioxidant activity, Peroxide leve
Green Synthesis, Characterization, and Antimicrobial Activity of Silver Nanoparticles from Brown Algae Padina Commersonii
No full textNanotechnology, which operates at the nanoscale (1-100 nm), is advancing due to the unique properties of materials exhibited at this scale, particularly increased surface area. Silver nanoparticles (AgNPs) are highly valued for their conductivity, stability, and therapeutic potential. Green synthesis offers an eco-friendly approach to nanoparticle production by utilizing biological compounds, including those found in marine algae like Padina commersonii, an edible brown algae species from the Hikkaduwa coast of Sri Lanka. The study's objective was to biosynthesize AgNPs using Padina commersonii, characterize the nanoparticles, and evaluate their antimicrobial activity. AgNPs were synthesized by combining crude methanol extract of the algae with silver nitrate. Characterization was conducted through various techniques, including UV-Vis spectroscopy, Dynamic Light Scattering (DLS), Zeta potential analysis, Scanning Electron Microscopy (SEM), Energy Dispersive X-ray (EDX) analysis, X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), and Raman spectroscopy. The colour shift from pale yellow to reddish-brown within 48 hours confirmed nanoparticle formation. UV-Vis spectrophotometry revealed a peak at 424 nm, indicating the presence of AgNPs. DLS analysis determined an average size of 73.19 nm, with a zeta potential of -21.5 mV, signifying stability. SEM images showed spherical nanoparticles with smooth surfaces, while EDX analysis confirmed 19.5% silver content by weight. XRD analysis indicated a face-centered cubic structure, and FTIR and Raman spectra identified proteins, phenolic compounds, and amines as capping agents. The synthesized AgNPs demonstrated significant antimicrobial effects against Staphylococcus aureus (12.77±0.58 mm), Escherichia coli (15.27±0.58 mm), Aspergillus niger (18.10±0.15 mm), and Candida albicans (17.43±0.57 mm), outperforming the crude extract of Padina commersonii. The antimicrobial potential of silver nanoparticles synthesized using Padina commersonii against bacterial strains Staphylococcus aureus (12.77±0.58 mm), Escherichia coli (15.27±0.58 mm), and fungal strains Aspergillus niger (18.10±0.15 mm) and Candida albicans (17.43±0.57 mm) was greater than that of the crude extract of Padina commersonii (S. aureus = 11.17±0.29 mm, E. coli=10.50±0.50mm, A. niger=12.66±0.10mm, C. albicans=15.66±0.10mm) These findings suggest that AgNPs synthesized through green methods offer a promising strategy for treating bacterial and fungal infections.
Keywords: Silver nanoparticles, Padina commersonii, Antimicrobial, Green synthesis, Characterizatio
Estimating the Greenhouse Gas Emissions of a Typical Wildlife Safari Tour: A Case Study from Yala National Park in the Dry Zone of Sri Lanka
No full textTourists are increasingly becoming environmentally conscious, driven by growing awareness of climate change and the environmental impact of tourism. This shift has led to a growing preference for low-carbon tourism options. Many travelers now seek destinations and experiences that prioritize renewable energy, eco-friendly transportation, and minimal waste generation. Wildlife tourism is a key component in Sri Lanka’s tourism mix. With Sri Lanka's tourism sector experiencing a significant resurgence in 2025, low-carbon wildlife tourism represents a sustainable approach to experiencing nature, while opening new opportunities. This study attempts to understand the GHG emission dynamics in a wildlife tourism setting with special reference to safari tours to identify decarbonizing opportunities. We estimated the carbon footprint of a typical safari tour at Yala National Park; one of the highly visited National Parks in Sri Lanka, using a combination of primary and secondary data. We surveyed 50 safari jeep drivers to gather emission-related details of vehicles/jeeps used for safari tours as well as tour routes, duration and passenger numbers. For this study, following the guidelines in ISO 14067:2018, the boundary of a safari tour was set from the point of entry to the point of exit through the gate of the Yala National Park. We used DEFRA/BEIS emission factors and IPCC guidelines for calculations. Secondary data such as monthly visitor numbers and numbers of vehicles entered the park were gathered from Department of Wildlife Conservation records from June 2023 to June 2024. Results suggest that a typical safari tour in Yala NP generates 24.7 kgCO2e emissions. The average number of persons per safari jeep is 5, hence this translates to 4.94 kgCO2e per tourist for a safari tour. We further analyzed the emissions associated with the hypothetical scenario of safari tour operation with 8 persons per jeep as a low carbon option. Under this scenario, the per tourist emission is 3 kgCO2e for a safari tour. This option can achieve 202,007.5 kgCO2e potential emission reductions per year. Overall, this study's findings provide important insights to the GHG emission profile of a wildlife tourism destination and support informed policy decisions to transform NPs to low-carbon tourism destinations.
Keywords: Sustainable tourism, GHG emissions, Wildlife tourism, Low-carbon tourism, Yala N
THE IMPORTANCE OF STOICISM IN EMPOWERING PEOPLE FOR ECONOMIC RECOVERY IN SRI LANKA: A CONCEPTUAL FRAMEWORK
Get PDFSri Lanka is currently recovering from a severe economic crisis. This paper explores the role of Stoicism, an ancient Greek philosophy, in assisting individuals and communities cope with adversity, facilitating recovery. The article examines how Stoic principles such as resilience, emotional regulation, and focusing on what is within one's control can potentially reduce mental health deterioration, improve stress management, and contribute to economic recovery through improved mental well-being. Additionally, it proposes interventions at the grassroots level, grounded in Stoic principles, to improve community-level productivity and overall economic resilience
Bio Inspired Aircraft Wing Design to Reduce Flow Generated Noise
Get PDFNoise generation from aircrafts has become a major problem in the current aviation industry. As a solution, scientists have conducted variety of research studies by modifying the wings with three main features of owl species which allow them to fly in silent. Those are leading edge serrations, trailing edge serrations and the porosity on the wings. Due to the increase of drag from porous designs, most of the flow generated noise reduction aimed research studies have conducted by applying leading edge serrations and trailing edge serrations. Though, there were no research performed by adding both leading edge serrations as well as trailing edge serrations on an airfoil implemented wing. Therefore, this research was conducted by modifying a NACA 0012 airfoil type wing by adding both leading edge serrations as well as trailing edge serrations. At first, this research considered the highest noise reduced leading edge and trailing edge serration geometries from literature and modified the NACA 0012 base wing. Then, the research considered the main three types of leading-edge serration geometries of one of a highest noise reducing owl species in the world called A. Otus owl and modified the NACA 0012 base wing using the serration geometries of their wing. The acoustic simulations were conducted along with the aerodynamic simulations to configure the noise reduction as well as the change in aerodynamics of the wing with different serration geometries. Finally, the highest noise reducing serration geometries and the lowest aerodynamic properties changing serration geometries were identified
Fire Distribution Analysis For The Faculty Of Engineering, University Of Sri Jayawardenepura
Get PDFThis study investigated the different modelling methods for the fire and evacuation process. Then identified different fire sources in the manufacturing laboratory of the faculty. This paper discussed, the applications of the Fire Dynamic Simulator (FDS) and discussed the outputs from FDS. The theoretical basis of related governing equations for the fire phenomena simulation and the theoretical background of human egress have been discussed. Furthermore, it identified the different fire sources of the manufacturing laboratory with the risk rating. Also, this paper explains how to perform a fire risk assessment and from that, an acetylene gas leak fire accident was selected for the simulation purpose. Then the theoretical background was discussed for Turbulence jet modelling. The smoke visibility capability calculates the distance a lighted sign can be seen in a smoke-filled environment, as well as smoke visibility obtained from the FDS smoke view results viewer. Finally, there will be some suggestions to improve the fire safety of the faculty manufacturing laboratory. This paper was created based on some research papers and books related to fire protection Engineering
Transient Thermal Simulation Based Design of a Remote Temperature Measuring System for Tire Molds
Get PDFThe curing process of tires significantly impacts their quality, performance, and production cost. Therefore, temperature control is the most crucial aspect of the curing process. Temperature measurement of the mold that reflects the tire temperature is done with human involvement, which has an associated health risk. Hence, this study aimed to develop a remote temperature measuring approach to avoid direct human involvement. The temperature distribution of the tire mold during the curing process was simulated using the transient thermal analysis system in Ansys workbench by maintaining the boundary conditions fixed. The optimal temperature measuring locations were evaluated to determine the best location to insert the temperature measuring sensor. Boundary conditions were created according to the requirement to maintain the internal temperature of the mold at the curing temperature (140 °C). Resistance Temperature Detectors (RTD), a contact-type temperature measuring device were identified as the most suitable for this application based on their high accuracy and stability. After selecting the temperature sensor and determining the insertion point, a wireless communication method was developed based on the ATmega328 microcontroller, in which the communication between the transmitter and receiver circuits occurs via the NRF24L01 2.4 GHz transceiver module. Thus, this remote mold temperature measurement approach would help eliminate human involvement in temperature measurement while providing accurate measurements for the curing process
The Relationship between Emotional Labor and Job Satisfaction among Nurses of Selected Private Hospitals in Sri Lanka with the Mediating Role of Emotions
Get PDFThe healthcare system in Sri Lanka is distinguished by its distinctive and sophisticated model, which combines elements of traditional and Western medicine. It is emerging as a highly competitive industry in Sri Lanka, with an enhanced consciousness regarding the medical-related elements in daily life. This study explores the nuanced relationship between emotional labor, emotions, and job satisfaction among nurses in private hospitals in Sri Lanka within the distinctive context of its healthcare system. Focusing on surface acting and deep acting as emotional labor strategies, the research delves into the emotions of anxiety, anger, fear, and happiness, considering their impact on job satisfaction. The current investigation is primarily based on the problem of identifying the intricate relationship between emotional labor, emotions, and job satisfaction, with a gap in existing literature in the Sri Lankan context. Thus, the primary objectives are to explore the associations between emotional labor (specifically surface acting and deep acting), emotions (anxiety, anger, fear, and happiness), and job satisfaction. The researchers collected data from five selected healthcare organizations and distributed 313 questionnaires to the study sample. The data collection process was primarily based on a simple random sampling method. The Pearson correlation analysis and the Hayes Process Model 4 Mediation Analysis were employed to unravel the direct and mediating role of emotions and emotional labor. Robust correlations regarding deep acting as a positive link with job satisfaction and surface acting as a negative link with job satisfaction are identified. The findings underscore the importance of addressing emotional labor dynamics in healthcare settings for enhanced employee well-being and improved patient care quality. This study significantly advances the understanding of the intricate relationship between emotional labor, emotions, and job satisfaction among nurses in private hospitals in Sri Lanka. The findings contribute to academic scholarship and offer actionable insights for healthcare management.
Key Words: Anger, Anxiety, Deep Acting, Emotional Labor, Emotions, Fear, Happiness, Surface Actin
Detection and Management of the Pharmaceutical Pollutants from Aquatic Systems - A Mini Review
Get PDFPharmaceutical residues in aquatic environments are common, and studies detailing their environmental fate has been given prominence in recent years. Since some pharmaceutical residues (environmentally persistent and stable drugs) are not eliminated using conventional wastewater treatments, research on the integrated methods is needed. Photocatalysis, ozonation, electrocoagulation, oxidation, adsorption, and biological treatments (phytoremediation, bioremediation) are generally used at waste water treatment plants. The most important environmental problem facing humanity is the increasing contamination of freshwater resources globally with hundreds of recalcitrant pharma micropollutants. In recent years, it has been acknowledged that research on the prevalence and destiny of pharmaceutical residues in aquatic habitats is vital. Detection of the drugs and finding solution for their removal from contaminated sites can be achieved with the optimization of biotic (microorganisms, algae, plant) and abiotic factors (light, pH, temperature, and carbon source). This mini review gives insight on the use of enzymes for the sensing of the drugs, enzyme assisted detoxification mechanism in plants as well as microorganisms. The biotic-abiotic coupled system and in site remediation processes are also discussed.Keywords: Drugs, Enzymes, Remediation, Toxicity, Phytoremediation, Wetlan
Evaluating the Impact of Brand Equity on Brand Evangelism Behavior with the Mediating Effect of Brand Trust: With Special Reference to the Institutional Market of Power Cable Industry in Sri Lanka
Get PDFWhile brand equity models are vigorously debated for their empirical validity, the notion has been investigated with various product horizons and market circumstances. Brand trust, proven to influence customer actions, is key to strong brand relationships, including brand evangelism. This study concentrated on the branding of industrial products, with the Sri Lankan cable market being the research specialty. It is observed that industrial product branding is an area where significant managerial challenges are attributed in terms of the results of brand relationships vs the investments made in brand building by Sri Lankan cable industry. Even from the standpoint of the industrial market, the trust element is a key influence in industrial product brands. Theoretical explanations and empirical reviews were used to support the hypotheses about brand equity and brand evangelism while the mediating role of brand trust was explicitly taken into consideration as a novelty supported by the commitment trust theory. The industrial market for cable brands in Sri Lanka was the study's focus, and managerial difficulties were especially discussed to explain the discrepancy between theory and practice. A deductive method of analysis was used, conceptualizing variables in accordance with the specified study topics. It used a quantitative research approach, having pretested the questionnaire in a pilot study, and using a multi-stage cluster sampling procedure. 131 respondents were conducted due to the limited number of contractors in the selected market segment following the data filtering procedure, taken into account for the final analysis. The study used descriptive statistical methods, correlation analysis and regression analysis using SPSS software to derive into conclusions. It was discovered that brand equity's effect on brand evangelism is mediated by brand trust. According to the findings, the study suggested managerial solutions to develop brand ambassadors for cable brands in Sri Lanka's industrial market. It attempted to give managerial ideas for the sector, urging how to combine brand-building strategies and methods for cable brands to produce brand evangelists while paying particular attention to the measurements for brand trust