Ceylon Journal of Science最新文献

{"title":"Catalytic derivatization of 2-Aminobenzo[d]thiazole for observing antibacterial activity and in silico analysis","authors":"S. Bepary, B. K. Biswas, F. M. Nazia, S. Islam, T. S. Juthy","doi":"10.4038/cjs.v52i3.8095","DOIUrl":"https://doi.org/10.4038/cjs.v52i3.8095","url":null,"abstract":"2-Aminobenzo[d]thiazoles have been converted to corresponding acetanilides and 2-hydroxy compounds for observing antibacterial activities. The acetylation was done by direct use of acetic acid, whereas the corresponding 2-hydroxy derivative was synthesized following various reaction conditions with or without a catalyst for observing the associated yield and ease of the reaction. In this study, the reaction yield was found to be between 20% and 86%. The synthesized acetanilides and the 2-hydroxy compounds were screened for antibacterial activity against various common pathogenic gram-positive and gram-negative organisms. Encouraging antimicrobial potential was noted from these small molecules. Finally, the compounds were taken for in silico analysis to observe the possible orientations in the binding site of the alanine racemase enzyme of Enterococcus faecalis.","PeriodicalId":9894,"journal":{"name":"Ceylon Journal of Science","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45281033","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A quality review of EIA: A comparative study of state-funded and International Aid Agency funded development projects in Sri Lanka","authors":"V. Ravi, N. Vimaladhas, V. Vimaladhas","doi":"10.4038/cjs.v52i3.8021","DOIUrl":"https://doi.org/10.4038/cjs.v52i3.8021","url":null,"abstract":"Environmental Impact Assessment (EIA) is a tool for mitigating the effects of developmental projects on the environment and promoting sustainable development. EIA is an expensive, and professionally engaged process that involves the public. Many countries around the world have long-standing laws in place connected to this topic, as well as solid knowledge and experience. One persistent argument against the efficacy of EIA in developing nations is that the procedure and quality differ from country to country. The International Aid Agencies (IAA) have their guidelines for protecting the environment while following local environmental assessment standards for any financing requirements. IAA involvement in the EIA process might significantly affect how well-written EIA reports are. To evaluate the assessment quality, six EIA reports from state-financed development projects (SL-EIAs) and another six development projects EIAs funded by the IAA (IAA-EIAs) in Sri Lanka were randomly chosen. LeeCooley review package (1990) was used to evaluate the Environmental Impact Statements (EIS) of each EIA. In this investigation, it was discovered that IAA-EIAs and SL-EIAs had a significant difference in overall quality. IAA-EIAs show values that range from highly satisfactory to satisfactory and each share 50 percent, whereas SL-EIAs indicate 83% satisfactory and 17 % of borderline quality. In comparison to the SL-EIAs, all four review areas of the IAA-EIAs performed notably well. While the SL-EIA shows good to borderline quality (0.66-0.72), all evaluated IAA-EIA reports reveal highly satisfactory to satisfactory (0.81-0.93) quality. The engagement of IAA in the environmental assessment has a considerable impact to improve assessment quality in comparison to the only domestic assessment. Finding the weak area in the SL-EIA process and adhering to the IAA standards would elevate the standard of the report.","PeriodicalId":9894,"journal":{"name":"Ceylon Journal of Science","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42811876","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Agent-based modelling of electric vehicle behaviour in a university environment","authors":"S. K. Jaslin, M. A. U. S. Navaratne, J. B. Ekanayake","doi":"10.4038/cjs.v52i3.8089","DOIUrl":"https://doi.org/10.4038/cjs.v52i3.8089","url":null,"abstract":"As the number of electric vehicles (EVs) increases, the strategic planning of charging infrastructure becomes a crucial matter. Vehicle parking time takes the longest at home and work. The residential is responsible for 75% of EV charging time, while the workplace is for 14%. The combination of EVs with intermittent energy sources has attracted considerable attention in recent years. It has several advantages, including significantly greening the entire EV usage cycle and attaining financial viability by lowering the direct peak demand on the grid. This study has described the agent-based infrastructure of the EV charging station model on university premises. It lets us obtain the best possible energy supply from solar PV, external batteries, and grid agents. Three charging scenarios (uncontrolled, vehicle-to-grid (V2G), and grid-to-vehicle (G2V)) are constructed and simulated with varying percentages of EV resemblance. Slow charging is included in the G2V scenario to improve the PV benefits in the EV charging model. The simulation result shows that slow charging in the workplace infrastructure increases the PV benefits of EV charging while reducing grid dependency.","PeriodicalId":9894,"journal":{"name":"Ceylon Journal of Science","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42240688","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Junior secondary students’ satisfaction of basic psychological needs and their achievement in physics","authors":"P. Vijayakumaran, P. Liyanage, W. Chandrasena","doi":"10.4038/cjs.v52i3.8071","DOIUrl":"https://doi.org/10.4038/cjs.v52i3.8071","url":null,"abstract":"Self-Determination Theory (SDT) is a broad theory of human development and wellness, with strong implications in education. According to SDT, three psychological needs are essential settings for self-growth, integrity and well-being viz., competence, autonomy, and relatedness (CAR). This study investigates the relations of junior secondary students’ physics achievement with the satisfaction of their Basic Psychological Needs (CAR). A mixed methods approach was used in the study and selected a convenience sample of 855 junior secondary students and 8 principals in all five educational zones in Jaffna District in the North Province, Sri Lanka. The student related quantitative data were collected using standard Korean Basic Psychological Needs Scale (K-BPNS) with four-point Likert scale and assessment test papers for each Grade. Qualitative data were gathered in interviews from eight principals to explore their views on current situation of physics teaching-learning processes according to the framework for comprehending motivation in SDT. Quantitative data were analysed descriptively using SPSS 20.0. Qualitative data were analysed in narrative analysis. The results revealed that students’ satisfaction with BPN (CAR) factors were directly correlated with their achievement in physics.  Principals’ perception on Reeve’s student-teacher dialectical frame is not at a satisfactory level. Thus, this study provides essential information for policymakers on enhancing students’ physics achievement at the junior secondary school level.","PeriodicalId":9894,"journal":{"name":"Ceylon Journal of Science","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43404465","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of extraction temperature on the phytochemicals, minerals and antioxidant properties of Telfairia occidentalis leaf extracts","authors":"A. J. Awoniyi, O. Ogunmola, O. Babatunde, O. M. Daniel","doi":"10.4038/cjs.v52i3.8207","DOIUrl":"https://doi.org/10.4038/cjs.v52i3.8207","url":null,"abstract":"Telfairia occidentalis leaves are known to possess many therapeutic potentials such as antidiabetic, anti-inflammatory, anticholesterolemic etc. To maximize their use in phytomedicine, the conditions used in preparation methods are crucial. Therefore, this study estimated the effect of extraction temperature on the phytochemicals, minerals, and antioxidant properties of T. occidentalis leaves. The powdered samples of T. occidentalis leaves were extracted using water at 1000C and 250C, respectively, followed by the phytochemical, mineral and antioxidant analyses of the plant extracts. The concentration of most constituent metabolites in the cold extract of T. occidentalis leaves was significantly (p < 0.05) higher than that of the hot extract. The highest mineral concentrations in hot and cold extracts of T. occidentalis leaves were sodium (2.22 mg/L) and potassium (2.77 mg/L), respectively. In the antioxidant study, the EC50  values (131.20 ± 1.70 μg/ml and 105.08 ± 0.54 μg/ml) of the hot extract of T. occidentalis leaves were significantly (p < 0.05) lower than those of the cold extract (228.17 ± 23.03 μg/ml and 151.47 ± 14.68 μg/ml). The study reveals that the extracts hold varying biological importance. The cold aqueous extract can be an excellent nutritional adjuvant for the supply of essential nutrients, whereas the hot aqueous extract can act as an important agent in ameliorating pathological conditions thrive on excessive free radical generation. Therefore, the different extraction procedures can be utilized based on the desired biological outcome.","PeriodicalId":9894,"journal":{"name":"Ceylon Journal of Science","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44771604","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Antivenoms for local effects of snake envenoming ","authors":"Umesha Madhushani, G. Isbister, W. Hodgson, S. Siribaddana, Anjana Silva","doi":"10.4038/cjs.v52i3.8209","DOIUrl":"https://doi.org/10.4038/cjs.v52i3.8209","url":null,"abstract":"Snake envenoming is a significant public health issue that disproportionately affects the poorest communities in the tropical regions. There is a spectrum of local effects following snakebite, including pain, swelling, bluish discolouration, haemorrhagic blistering, local tissue necrosis and gangrene at the bite site. In severe local envenomings, significant tissue loss and impaired function can occur and may result in permanent disability in snakebite survivors. Although the mainstay of hospital treatment for snake envenoming is antivenom, its effectiveness for local effects remains contentious.  The preclinical efficacy of antivenoms against the local effects of envenoming is examined with a range of in-vivo and in-vitro tests. Most of these tests are only capable of examining the ability of the antivenom to prevent, rather than reverse, the local effect. A limitation of the above tests is that they do not consider venom pharmacokinetics or the time course of irreversible effects in envenomed humans. Therefore, more clinically relevant experimental models of antivenom efficacy are required. We searched MEDLINE for studies on the local effects of snakebite. The current clinical literature on the effectiveness of antivenom for local effects appears to be limited. We identified only two randomised trials that compared antivenom with placebo and six randomised trials that tested the effectiveness of one antivenom or one dosage regimen of an antivenom compared to another antivenom or different dosage of antivenom for preventing or reversing the local effects. All these studies were on viperine envenomings. In addition, several studies without a control/comparative group have commented on antivenom effectiveness, although they invariably have significant bias. The existing studies had contrasting conclusions, including no effect of antivenom, antivenom halting the progression of local effects, early antivenom preventing the occurrence of severe local effects including necrosis, early antivenom leading to faster functional improvement, antivenom accelerating the resolution of local effects, or no conclusion. Future research needs to focus on well-designed studies investigating whether the early administration of antivenom will prevent severe local effects.","PeriodicalId":9894,"journal":{"name":"Ceylon Journal of Science","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47908453","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of ocean circulation and chlorophyll-a concentration on yellowfin tuna catch rates in Sri Lankan logline fishery","authors":"U. S. Maddumage, J. Rajapaksha, J. Gunatilake","doi":"10.4038/cjs.v52i3.8208","DOIUrl":"https://doi.org/10.4038/cjs.v52i3.8208","url":null,"abstract":"Sri Lanka has access to fishery resources in the Indian Ocean due to its location. While traditional fishing methods are still used in the Sri Lankan fishery industry, modern technologies such as remote sensing and GIS are employed to determine spatiotemporal distribution of tuna fish resources in the offshore fishery industry. However, due to uncertain catch rates, Sri Lankan fishers report low catch per unit effort, leading to increased fishing duration to meet targeted catch. Potential fishing areas can be identified based on oceanographic conditions to reduce search time and improve efficiency, particularly for highly migratory species like yellowfin tuna. Therefore, this study is focused on identifying the impact of subsurface ocean currents and chlorophyll-a concentration on yellowfin tuna aggregations. The study analysed fishery and oceanographic data from January 2018 to December 2019 within a latitudinal range of 0°N to 20°N and a longitudinal range of 70°E to 90°E. The data were gridded at a resolution of 0.25 degrees and then matched for analysis. The generalized additive model (GAM) and the empirical cumulative distribution function (ECDF) were applied to identify the nature of relationships between CPUE and the oceanographic conditions. The results showed high tuna aggregations occurred in chlorophyll-a concentration between 0.3– 0.4 mg/m3 and current speed less than 0.4 m/s at a depth of 60 – 75 m of Sri Lankan longliners. Yellowfin tuna fishable aggregations were available throughout the year, although the spatial distribution of yellowfin tuna varied depending on the prevailing oceanographic conditions. Thus, searching for fishing locations based on oceanographic factors is essential for successful fishing operations. Hence, tuna harvest can be enhanced by maintaining fishing areas and the longline depth according to the oceanographic factors.","PeriodicalId":9894,"journal":{"name":"Ceylon Journal of Science","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43094697","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The rainbow vertex connection number of ladder graphs and Roach graphs","authors":"W. D. D. P. Dewananda, K. K. K. R. Perera","doi":"10.4038/cjs.v52i3.8045","DOIUrl":"https://doi.org/10.4038/cjs.v52i3.8045","url":null,"abstract":"A vertex-coloured graph G is said to be rainbow vertex-connected, if every two vertices of G are connected by a path whose internal vertices have distinct colours. The rainbow vertex-connection number of a connected graph G, denoted by rvc(G), is the smallest number of colours that are needed to make G, a rainbow vertex-connected. This study focuses on deriving formulas for the rainbow vertex connectivity number of a simple ladder graph and a roach graph.","PeriodicalId":9894,"journal":{"name":"Ceylon Journal of Science","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42568463","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Biofilm Enriched rock phosphate as a potential phosphorous fertilizer to replace triple super phosphate in rice cultivation: A preliminary field trial","authors":"J. Jayaneththi, G. Seneviratne, H. Madawala, M. G. T. S. Amarasekara","doi":"10.4038/cjs.v52i3.8091","DOIUrl":"https://doi.org/10.4038/cjs.v52i3.8091","url":null,"abstract":"Rock Phosphate (RP), derived from natural apatite mined from Eppawala (ERP), is identified as a possible substitute for Triple Super Phosphate (TSP). However, its application is limited due to low solubility. If the bio-solubility is enhanced, ERP can be used as a phosphorous (P) fertilizer for annual crops. The present study focused on using an effective biofilm formulation identified after screening several known phosphate solubilizing biofilms, and introducing a biofilm-enriched ERP (BEE) as an alternative for TSP in rice cultivation. Two field trials were conducted in two consecutive seasons, dry season in 2018 (Yala) and the wet in 2018/2019 (Maha). The existing chemical fertilizer dosage (CF) recommended for rice by the Department of Agriculture (DOA) was modified by fully replacing TSP-P with BEE, along with 65% nitrogen (N) and potassium (K) fertilizers (CFNK). Three different rates of BEE, 65, 80 and 100% (equivalent to TSP-P recommended by the DOA) were tested (CFNK + 65 BEE, CFNK + 80 BEE and CFNK + 100 BEE) against CF. Results revealed that the rate of 100% BEE performed better than that of other rates of BEE (65% and 80%), while the same recorded significantly higher grain yields in both seasons compared to all other treatments. Moreover, plant growth parameters viz. shoot and root dry masses, height, and panicle length were also recorded higher values with CFNK + 100BEE application than the control (CF). Therefore, the BEE can be suggested as an alternative to TSP for rice cultivation, with an added advantage of using a reduced dosage of N and K fertilizers. However, further studies are needed to test the BEE under different soil and climatic conditions in the country.","PeriodicalId":9894,"journal":{"name":"Ceylon Journal of Science","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44995143","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Wind power calculation based on sums of diffusion method and a novel power curve approximation model","authors":"H. Bandarathilake, G. Palamakumbura","doi":"10.4038/cjs.v52i2.8023","DOIUrl":"https://doi.org/10.4038/cjs.v52i2.8023","url":null,"abstract":"","PeriodicalId":9894,"journal":{"name":"Ceylon Journal of Science","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42913677","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}