University of Sri Jayewardenepura: Journals & Proceedings
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The implication of Canvas to enhance English language teaching and learning: A case study conducted at the Nawaloka College of Higher Studies
Get PDFTechnology has had a significant impact on education over the past few decades leading to a transition from paper-based learning towards digital tools. In response, learning management systems were integrated to assist classroom management. However, the perceptions of its users are crucial in determining the success of technology integration. Given that, the study aims to investigate the implication of the Canvas application to enhance English language teaching and learning at Nawaloka College of Higher Studies, Sri Lanka focusing on its user perceptions. Using the qualitative research approach, a questionnaire consisting of both close-ended and open-ended questions was distributed among a sample of 100 students from Engineering and Business backgrounds following the Academic and Communication Skills A module and 6 experienced English teachers. Accordingly, thematic analysis exercised on the data indicated the ease of use, increased motivation and accessibility as contributing to the user’s positive attitude when using the application. Thus, with the identification of benefits achieved through Canvas which outweigh the difficulties such as poor network and lack of knowledge in technology; the study recommends the necessity for higher studies institutes to integrate the same for an enhanced English language teaching and learning experience in tertiary education.
DOI: http://doi.org/10.31357/fhss/vjhss.v09i02.0
A Review of Biological Foundations of Anger
Get PDFAnger, happiness, sadness, fear, surprise, and disgust are the six fundamental emotions that people can experience. Anger is a strong feeling of annoyance, displeasure, or hostility. It is a blaming emotion that is aimed against individuals, and it frequently leads to violent actions. However, anger serves survival purposes and is embedded in humans. While anger is typically viewed as a psychological or social phenomenon, it also has a biological basis. This literature review focuses on anger and its underlying biological foundations. The biological basis of anger can be explained through the activation of the amygdala, which plays a crucial role in emotional processing. Additionally, studies have shown that anger is associated with decreased activity in the prefrontal cortex. When a person becomes angry, this region of the brain is less active, leading to impulsive behaviors and decreased rational thinking. This explains why individuals often engage in aggressive or violent behaviors when angry. Understanding the biological basis of anger can help us better manage and control this emotion. By recognizing the physiological changes that occur when we become angry, we can take steps to calm ourselves down and develop healthier coping mechanisms.Keywords: Emotions, Anger, Amygdala, Prefrontal cortex, Biological basi
මාතර හෙළ වෙදකම පිළිබඳ විමර්ශනාත්මක අධ්යයනයක්
No full textHela wedakama is Sri Lanka’s local helth insurance system. That has existed since time immemorial.This was not introduced from any other country, but was produced by the ancient inhabitants of ourcountry. Traditional Hela medicine treats the three categories of human, animal and non-humanTraditional medicine helps in the prevention of physical, mental, infectious and non-infectious diseases.The specialties of Hela medicine are unique to each region and they differ from each other. Matararegion has been known as the birth place of Hela medicine since time immemorial. Matara Helavedakama is at the forefront in providing treatment for human and non-human categories as well asphysical, mental, infectious and non-infectious diseases. Matara Hela medicine is special, because it isbased on the practices of the area for disease prevention. Accordingly, the content and practices ofMatara Hela medicine were studied in this research. Data was collected through library reference, fieldstudy and interviews. According to the facts revealed in the study, it was possible to identify thepeculiarities of Hela medicine, that is unique to the Matara area
Solid Waste Challenges and Management in a Traditional Sahelian City: A Case Study of Sokoto, Nigeria
Get PDFThis study assessed the solid waste generation, management, and consequences in the traditional city of Sokoto. The utmost challenges facing this Sahel region include scarcity of modernized and control measures of waste resulting from daily hectic impacts on the community. In this city, solid waste is characterized by inefficient control, insufficient coverage of collection system and improper disposal methods. The increasing population of residents has accelerated more pollution of all categories, and the consequence is a dearth of hygienic standards. This work further sampled different materials from heaps of waste such as; the level of sub-soils at 0-30 cm (at random) from each of the dump sites to determine the extent of heavy metal concentrations and for fertility supplement in comparison with the National Environmental Standards and Regulations Enforcement Agency (NESREA). Fifty structural questionnaires were administered randomly to selected residents around dumping sites and the staff of Sokoto Waste Management &Planning Board to solicit relevant information that can assist the governments, stakeholders, and waste control agencies. Also, Landsat data was utilized to map out the waste sites for spatio-temporal analysis. Results indicated that 89% of respondents agreed that Sokoto metropolis is characterized by untidiness with masquerades of biodegradable wastes, while major streets especially in the congested areas which displayed a lot of drains and channels remain blocked.
DOI: http://doi.org/10.31357/fhss/vjhss.v09i01.0
Removal of Nitrate and Phosphate in Wastewater by Composite Rice Husk Ash and Dolomite
Get PDFExcess nitrate and phosphate present in water contribute to water quality degradation, altering the structure and functions of aquatic ecosystems, and also induces socio-economic impacts by facilitating eutrophication. Although many techniques are available for the removal of nitrate and phosphate from wastewater, adsorption using solid materials as adsorbents is simpler, more effective, and cheaper process than other techniques due to the possibility of using any conventional or non-conventional material as the adsorbent. Therefore, this study was conducted to investigate the potential of composite rice husk ash and dolomite to remove phosphates and nitrates in wastewater by adsorption. Batch studies were conducted for composite rice husk ash and dolomite to determine the effect of pH, initial concentration, and contact time on the anion adsorption. For that, the sieved RHA and dolomite were mixed in 1:5 ratio and used as the adsorbent maintaining adsorbent concentration at 60 gL-1 . The adsorption capacity of composite rice husk ash and dolomite for the removal of phosphates and nitrates was evaluated in the range of pH 3 to 9, changing initial anion concentrations from 20-200 mgL-1 for 24 h contact time. According to the results, overall adsorption of both phosphates and nitrates onto composite rice husk ash and dolomite was increased with the increase in pH. The adsorption of both phosphates and nitrates reached highest level at pH~8. Furthermore, isotherm studies showed that the adsorption of both phosphate and nitrate onto composite rice husk ash and dolomite was well fitted to the Langmuir isotherm model indicating a monolayer adsorption. The dimensionless constant was ranged in between 0 and 1 for both phosphate and nitrate adsorption indicating a favourable adsorption with a strong affinity between the solute and the adsorbent. The maximum adsorption capacities of phosphate and nitrate were 5.59 mg g-1 and 1.84 mg g-1 , respectively. According to the kinetic studies, adsorption of both phosphate and nitrate was well described by pseudo second-order model suggesting chemical sorption. Importantly, the equilibrium for phosphate and nitrate adsorption was achieved within just 60 minutes and 45 minutes, respectively under the experimental conditions. In summary, this study concludes that rice husk ash and dolomite composite is an effective adsorbent for the removal of phosphate and nitrate in wastewater, offering an eco-friendly and cost-effective alternative for addressing water pollution challenges, thereby contributing to the restoration of water quality, and associated socio-economic well-being.
Keywords: Adsorption, Isotherm models, Kinetic models, pH, Phosphate, Nitrat
Contamination of Buried Plastic Marine Litter on Sandy Beaches in the West Coast of Sri Lanka
Get PDFSandy beaches act as an interface between land and sea and can serve as an indicator of the level of contamination in the marine environment. The beach can be both a source and a sink for marine litter contamination. Long-term accumulation of buried plastic marine litter (BPML) can produce microplastics by mechanical destruction and/or UV-degradation. This study aims to investigate the contamination and distribution of BPML in the Crow Island (CR) and Wattala (WT) beach areas during the Northeast monsoon. CR had a significantly higher anthropogenic load compared to WT beach. BPML (>5 mm) was determined in 12 quadrats (0.5×0.5 m) per beach area. From each quadrat, sand samples (2 sand samples per quadrat) were obtained in shallow and deep layers of the beach (surface to 3 cm, and 3 cm to 6 cm respectively). The fraction of the mass of coarser sand was determined to identify the relationship between the coarseness of the sand sample and BPML contamination. Coarseness of the sample was determined by removing fine sand using a 1 mm sieve. Accumulation patterns of BPML were analysed between the storm line and sand dune. On average, 21 items/kg Dry Weight (DW) and 7 items/kg DW were collected from sand samples from shallow and deep layers of the CR beach, respectively. In contrast, the WT beach area had almost no plastic pieces on average in a kilogram of dried sand samples collected from both depths. Out of the 24 sand samples collected from the WT beach, only 7 of them contained plastic pieces. Characterization of the polymers of the BPML was carried out using ATR-FTIR. Shallow and deep layers of sample from CR beach contained Polyethylene (10 items/kg DW and 3 items/kg DW respectively) and polyethylene terephthalate (5 items/kg DW and 2 items/ kg DW respectively) type BPML in high amounts. BPML accumulation on the CR beach was significantly affected by the depth of the beach and distance from the storm line (p<0.05, One-way ANOVA). High contamination by BPML is found to be associated with coarser sands. The average fraction of coarser sand for samples collected from the shallow and deep layers of the CR beach near the storm line is 17.4% and 26.1%, respectively, which indicates high contamination of plastics in the deep layer compared to the shallow layer. In contrast, the shallow layer contained a high percentage of coarse sand (5.3%) compared to the deep layer (3.7%) near the sand dune or vegetation. Findings indicate encouraging mitigatory measures to clean up marine litter focusing on both shallow and deep layers is recommended. Keywords: West Coast, Buried plastic marine litter, ATR-FTIR, Coarser sands >< 0.05, One-way ANOVA). High contamination by BPML is found to be associated with coarser sands. The average fraction of coarser sand for samples collected from the shallow and deep layers of the CR beach near the storm line is 17.4% and 26.1%, respectively, which indicates high contamination of plastics in the deep layer compared to the shallow layer. In contrast, the shallow layer contained a high percentage of coarse sand (5.3%) compared to the deep layer (3.7%) near the sand dune or vegetation. Findings indicate encouraging mitigatory measures to clean up marine litter focusing on both shallow and deep layers is recommended.
Keywords: West Coast, Buried plastic marine litter, ATR-FTIR, Coarser sand
Graphene Oxide Coated Sand Composites as Molecular Sieves to Mitigate Water Contaminants
Get PDFThis research focuses on the synthesis of a novel adsorbent, a sand/graphene oxide composite with five layers of graphene oxide coating, referred to as S-GO5. The primary aim of this study is to assess the potential suitability of S-GO5 as a molecular sieving material via the adsorption of Methylene blue (MB) dye and 2-methyl-4-chlorophenoxyacetic acid (MCPA) pesticide molecules. The composite is created through a stepwise deposition of graphene oxide onto river sand using a thermal annealing process. Characterization studies conducted with scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FT-IR) reveal a non-uniform graphene oxide coating on the sand's surface and the incorporation of oxygenated functional groups within the composite structure. The study compares the adsorption capacity of S-GO5 with other sorbent materials like activated carbon, graphene oxide, and sand, for the removal of MB dye and MCPA. For the analysis of MB dye and MCPA adsorption, UV visible spectroscopy (665 nm) and high[1]performance liquid chromatography (HPLC) methods were employed respectively. The optimization studies for MB adsorption on S-GO5 revealed that the ideal conditions are a concentration of 5 mg/L, a dosage of 0.09 g, a contact time of 20 minutes, at pH 9. Focusing on the adsorption of MCPA onto the S-GO5, the optimum concentration, dosage, and contact time were 75 mg/L, 0.05 g, and 105 minutes respectively, at neutral pH values. The investigation of adsorption equilibrium isotherms indicated that the Freundlich model best describes the adsorption process, with high correlation coefficients for both MB and MCPA. Additionally, adsorption kinetics analysis suggests a pseudo-second-order model best fits the data, indicating a chemical sorption mechanism governing the adsorption process. It is evident that MB (98.6%) has a significantly higher adsorption capacity on S-GO5 compared to MCPA (53.3%). The adsorption capacity values of MB, and MCPA were 52. 861 mg/g and 4.7316 mg/g respectively. Despite MB having a cationic charge and MCPA being either neutral or negatively charged in solution, the S-GO5 composite demonstrates a remarkable adsorption capacity for both compounds. This suggests that the synthesized composite could be a promising solution for molecular sieving material, owing to the removing positively charged molecules (MB) as well as negatively charged (MCPA) pesticide contaminants from water.
Keywords: Adsorption, Graphene, Sand, Dye, Pesticide
Support from the research project PS/DSP/CKDU/ 06/3.5 Establish a CKDU Information and Research Centre at the University of Kelaniya, Sri Lanka is acknowledged
Beach Cleanliness using the Clean Coast Index at a Recreational Beach: A Case Study of Charty Beach, Northern Sri Lanka
Get PDFMarine litter is a major environmental concern and has a huge impact on the cleanliness of beaches in Sri Lanka. The Clean Coast Index (CCI) is a tool that monitors marine debris as a beach cleanliness indicator and is used to evaluate the actual cleanliness of the coast. The aim of this first investigation is to assess the quantity of marine debris, determine the cleanliness of the beach using CCI and identify the sources of marine debris using the basic assumption method and the matrix scoring technique. A total of ten surveys were conducted between December 2020 and April 2021. Two transects of sampling were carried out, each with a dimension of 100 m in length and 5 m in width, covering an area of 500 m2. The marine litter greater than 2.5 cm in the longest dimension was collected, quantified and classified into eight distinct types. The average marine debris density on the beach was 0.106 items m-2 and 0.574 gm-2. Plastic (92%) was found to be the most abundant type of marine debris. The highest CCI recorded (13) was in December 2020, while the lowest (CCI=5) was recorded in March 2021. As the first study of actual beach cleanliness at Charty Beach in northern Sri Lanka, the findings show that the average beach cleanliness was moderate, with a CCI of 9. When the matrix scoring technique and the basic assumption method were used to determine the source of marine debris, both methods showed that recreational activities, smoke- related activities, and fishing activities are the main contributors to beach pollution. Quantifying beach cleanliness is an effective method to attract beachgoers and keep them coming back to bathing beaches. Therefore, continuous monitoring of beach cleanliness is important for environmental conservation and the sustainable development of coastal areas.
Keywords: Basic assumption method, Beach cleanliness, Clean Coast Index, Marine debris, Matrix scoring techniqu
GIS-Based Approach to Identify High Risk Zones for Floods and Evacuation Centres
Get PDFUrban areas are vulnerable to both natural and man-made disasters, which can put the lives of the population at risk. In order to protect them, an effective evacuation plan must be in place. This research study proposes a GIS-based system that utilizes a multi-criteria analysis method to identify safe areas for evacuees and determine the best evacuation routes from the disaster site to the designated safe areas. The aim is to minimize the time required for the evacuation process to be completed. Jaffna is one of the areas that suffer from seasonal flood disaster annually. The suitability of evacuation centres can be determined based on several criteria such as Elevation, LULC pattern, distance from road, distance from water bodies, slope and rainfall. The aim of the study was to identify suitable evacuation centres after calculating required resources for all evacuees, create short and safe routes for navigation in a disaster situation. ArcGIS Pro main software was used for final route analysis along with network analysis tools and ArcMap package was used for all layer creation and multi-criteria analysis. Multi-criteria evaluation method was chosen to analyse the suitable areas and Analytical hierarchical process was used to assign the weights for each primary criterion. Those are providing suitable evacuation centres with 80% validity and found the route risk zones to evacuation centres. The weights for primary criteria were assigned by using pairwise comparison matrices. All these layers were overlapped according to their weights and final suitable weighted overlay map was prepared and it was reclassified as 1, 2, 3, 4 and 5 where 1 is less rating and 5 is high rating. More suitable locations were found as the best evacuation centres. Closest evacuation shelter area from all flood hazard regions were identified by using closet facilities under the network Analysis. Hazard residents was taken as incidents and evacuation buildings Points are chosen for facilities. Nearest evacuation shelter facility for a hazard area was identified by analysing the attribute table of routes in closet facilities. The result of the study suggests a number of disaster management processes for the administration and general public.
Keywords: Flood, Risk, GIS, Analytical hierarchical process, Disaster managemen
Lipid Yields and Fatty Acid Composition if Indigenous Microalgae, Isolated from the Beira, and Diyawanna Urban Lakes, for Sustainable Biofuel Production in Sri Lanka
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Biofuels are carbon-neutral combustibles produced from renewable biomass. Third generation biofuels, derived from microalgal biomass, are distinctly superior to their preceding generations, due to higher productivity and resource use efficiency of microalgae compared to conventional energy crops. It is a viable source of sustainable energy for our country due to the availability of water, ambient temperatures and year-round sunlight needed for microalgae cultivation, and most importantly, the abundance of diverse microalgae species. However, these native microalgae are relatively unexplored for their productivities and thereby, greatly underutilized. This research was aimed to investigate the lipid yields and fatty acid compositions of local freshwater microalgae, and to identify their potential for biodiesel production. This was carried out by (1) microalgae isolation and morphological identification (2) microalgae cultivation (3) biomass harvesting, lipid extraction, gravimetric measurement of extracted lipids and (4) acid-catalysed transesterification, followed by GCMS analysis of the biodiesel product. Chlorella sp., Chlorococcum sp. and Chlamydomonas sp. were isolated from Beira/ Diyawanna Lakes using streak plate technique in solid standard BBM media. They were next cultivated under axenic conditions in liquid standard BBM media under 16: 8 (light: dark), at 25°C for 20 days in duplicates. The biomass was then harvested using alum, dried to reach a constant weight and the Bligh and Dyer lipid extraction was done in triplicate. The extracted lipids were trans-esterified with methanol, using sulfuric acid catalyst at 90° C for 60 minutes. The separated product was analysed by GCMS. Chlorella sp., Chlorococcum sp. and Chlamydomonas sp. cultivated under standard conditions gave average lipid yields of 11.34±1.01%, 15.00±1.40% and 2.10±0.50% respectively. Average lipid yield of Chlamydomonas sp. was significantly lower than the other two species at 95% confidence level (Two-sample T test on SPSS Version 21). GCMS analysis of the biodiesel product from Chlorella sp. indicated significant levels of saturated fatty acids including palmitic and stearic acids, monounsaturated fatty acids like cis-11- eicosenoic acid and polyunsaturated fatty acids including linoleic and linolenic acids. The fatty acid ratios were used to calculate the saturation value, cetane number, density, iodine value and pour point of the produced biodiesel. These quality parameters were in accordance with the ASTM D6751- 20a standards. Therefore, with a substantial yield and fatty acid composition of intracellular lipids, this local species of Chlorella can be a prospective candidate for sustainable bioenergy production in Sri Lanka.
Keywords: Chlorella, Chlorococcum, Chlamydomonas, Microalgal lipids, Biodiese