Ruhuna Journal of Science最新文献_第4页

Analysis of rainfall trends and variabilities for three decades in Sub – Sahara Africa 撒哈拉以南非洲三十年来降雨趋势和变化分析

Ruhuna Journal of Science Pub Date : 2021-09-15 DOI: 10.4038/rjs.v12i1.100

F. O. Aweda, A. A. Adeniji, J. Akinpelu, Ayodele J. Abiodun

{"title":"Analysis of rainfall trends and variabilities for three decades in Sub – Sahara Africa","authors":"F. O. Aweda, A. A. Adeniji, J. Akinpelu, Ayodele J. Abiodun","doi":"10.4038/rjs.v12i1.100","DOIUrl":"https://doi.org/10.4038/rjs.v12i1.100","url":null,"abstract":"Rainfall trend is an important climatic factor that influences agricultural products, groundwater production, drainage planning, commercial and industrial activities. The research aims to determine the trends and variability of monthly, seasonal, and annual rainfall for 30 years (from 1980 to 2010) in Sokoto (13.0059° N, 5.2476° E) and Maiduguri (11. 8333° N, 13.1500° E) using archives data obtained from the Nigeria Meteorological Agency (NiMet), Oshodi Lagos Nigeria. Statistical models were used to analyze the data. The results reveal that the maximum rainfall recorded was 371.60 mm at Maiduguri station and 374.90 mm at Sokoto station which shows a higher rainfall peak in Sokoto than Maiduguri. The coefficient of variation in the Sokoto station (126.39%) was higher than that of Maiduguri station (61.78%) which indicates that there was more rainfall variability in Sokoto than in Maiduguri. Seasonally, the average rainfall recorded in both stations was 61.78% and 126.39% respectively. No rainfall was recorded in January, February, and November for Maiduguri station, more so, no rainfall was recorded in January, November, and December for Sokoto station. According to Man-Kendal trend analysis, significant trends (p<0.5) were observed in Maiduguri and Sokoto. Therefore, the modelled statistical approach on rainfall trends and variability revealed that the peak month of annual rainfall is between June and September for the two stations. It can be recommended that the government should make favourable policies to utilize the rainfall received during this period to store more water in reservoirs and construction of water channels across the country.","PeriodicalId":56207,"journal":{"name":"Ruhuna Journal of Science","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48067587","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}

引用次数: 3

Modelling non-life insurance in Sri Lanka using Cox Hazard Model and classification of risky customers 使用Cox风险模型和风险客户分类对斯里兰卡非人寿保险进行建模

Ruhuna Journal of Science Pub Date : 2020-12-31 DOI: 10.4038/RJS.V11I2.91

W. A. D. Mel, W. A. P. A. Chathurangani

{"title":"Modelling non-life insurance in Sri Lanka using Cox Hazard Model and classification of risky customers","authors":"W. A. D. Mel, W. A. P. A. Chathurangani","doi":"10.4038/RJS.V11I2.91","DOIUrl":"https://doi.org/10.4038/RJS.V11I2.91","url":null,"abstract":"Some of the major factors that help the decision-making process of an insurance company include Time of the first claim (TFC), claim Size and the frequency of claims. However, in most situations researchers focus mainly on the second and third factors mentioned above. We hypothesize the importance of the TFC of an insurance contract in the decision-making process. Empirical evidence of motor vehicle insurance data in Sri Lanka suggests that nine covariates are responsible for the claim sizes. In the current study, our main objective is to find the key factors of those nine that are responsible for the TFC of the insurance contract. This study is based on the claim data in the whole year of 2016 of non-life insurance policies of a particular insurance company in Sri Lanka. Considering the TFC as right-censored data, selected nonparametric methods, i.e., Kaplan-Meier, Nelson-Aalen estimators, and Cox Proportional Hazard Model are used to analyze the data. We identified the five most influential covariates namely, vehicle type, log of Premium Value and that of Assured Sum, the lease type and the age range via fitting the Cox Model to TFC data. After a thorough residual analysis, the Logistic regression model has been used to identify the important covariates to classify future customers as risky or not. \u0000 \u0000Key words: Classification, Cox Proportional Hazard model, Kaplan-Meier, Right-censored","PeriodicalId":56207,"journal":{"name":"Ruhuna Journal of Science","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48175584","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}

引用次数: 0

Antioxidant and anti-inflammatory potential, and chemical composition of fractions of ethanol extract of Annona muricata leaf 番荔枝叶乙醇提取物的抗氧化、抗炎活性及化学成分研究

Ruhuna Journal of Science Pub Date : 2020-12-31 DOI: 10.4038/RJS.V11I2.92

Idorenyin Nwaehujor, G. Olatunji, O. Fabiyi, S. Akande

{"title":"Antioxidant and anti-inflammatory potential, and chemical composition of fractions of ethanol extract of Annona muricata leaf","authors":"Idorenyin Nwaehujor, G. Olatunji, O. Fabiyi, S. Akande","doi":"10.4038/RJS.V11I2.92","DOIUrl":"https://doi.org/10.4038/RJS.V11I2.92","url":null,"abstract":"Serious health challenges have been associated with inflammation which is a major cause of mortality in the world. This study evaluated the antioxidant, anti-inflammatory potential, and chemical compositions of fractions of ethanol extract of Annona muricata leaf. The leaves were dried at room temperature, blended and extracted in sequential with solvents of varying degree of polarities, i.e., n-hexane, ethyl acetate and ethanol. Ethanol extract was fractionated via solvent-solvent partitioning into five fractions, i.e., n-hexane fraction (F1), dichloromethane fraction (F2), dichloromethane/ methanol (1:1) fraction (F3), methanol fraction (F4), and ethanol fraction (F5). These fractions were examined for their in-vitro antioxidant activities on DPPH, ABTS and H2O2 while the anti-inflammatory activities were investigated using lipoxygenase inhibition, proteinase inhibition and membrane stabilization assays. The F4 being the most active fraction was further analyzed with GCMS to determine its chemical compositions. The results showed that F4 had the highest H2O2 scavenging activity at 10–100 µg/mL. The activity of F4 at 50 µg/mL was significantly higher (P<0.05) than that of other treatments including the standard (Vitamin C). Activity of F4 also showed significantly higher (P<0.05) membrane stabilization than other fractions at 50-100 µg/mL. F4 exhibited higher antioxidant and anti-inflammatory activities than the other fractions. The activity of this fraction could be attributed to the synergetic effect of various antioxidant compounds present in the fraction. Some of the bioactive compounds identified in the GC-MS of F4 were coumaran, tyrosol, phytol, tetracosanol, elaidic acid methyl ester and β-sitosterol. Keywords: Bioactivity, concentration, inhibition, radical scavenging","PeriodicalId":56207,"journal":{"name":"Ruhuna Journal of Science","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48591125","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}

引用次数: 2

Survival modelling of teenage childbirth among Nigerian women 尼日利亚妇女青少年分娩的生存模型

Ruhuna Journal of Science Pub Date : 2020-12-31 DOI: 10.4038/RJS.V11I2.93

O. Oladuti

{"title":"Survival modelling of teenage childbirth among Nigerian women","authors":"O. Oladuti","doi":"10.4038/RJS.V11I2.93","DOIUrl":"https://doi.org/10.4038/RJS.V11I2.93","url":null,"abstract":"Childbearing is an essential event in woman’s life when she neglects her education and career for motherhood. The main cause of population growth in Nigeria is teenage childbearing as reported by many researchers with no significant intervention to reduce this menace. This work is designed to compare the results of Cox, Gompertz and Weibull models with a view to determine the model that best fits the data. To evaluate the effect of some risk factors on the hazard of teenage childbirth among Nigerian women, data obtained from National Demographic Health Survey 2013 was analysed. Results of the analysis showed that having a child at teen age depends on geopolitical zone, location, educational level, circumcision, household wealth index, religion belief, use of contraceptive, whether had a terminated pregnancy, forced sexual acts, awareness of HIV/AIDS, STI and the age of first sexual acts. Akaike Information Criterion (AIC) was employed to evaluate performances of the three models. Weibull regression model has the minimum AIC value compared to both Gompertz and Cox regression models. This shows that Weibull regression model provides best fit to the data. \u0000 \u0000Keywords: Cox proportional hazard model, risk factors, survival time, teenage childbirth","PeriodicalId":56207,"journal":{"name":"Ruhuna Journal of Science","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46274997","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}

引用次数: 0

Preliminary study on diversity of intertidal gastropods in Barangay Day-asan, Surigao City, Philippines 菲律宾苏里高Barangay Day-asan潮间带腹足类动物多样性的初步研究

Ruhuna Journal of Science Pub Date : 2019-06-30 DOI: 10.4038/RJS.V10I1.54

V. Abarquez, N. Mendez, G. Galan

{"title":"Preliminary study on diversity of intertidal gastropods in Barangay Day-asan, Surigao City, Philippines","authors":"V. Abarquez, N. Mendez, G. Galan","doi":"10.4038/RJS.V10I1.54","DOIUrl":"https://doi.org/10.4038/RJS.V10I1.54","url":null,"abstract":"Unregulated harvesting and habitat degradation of marine \u0000gastropods are major anthropogenic activities done by the local people in Barangay Day-asan, Surigao City, Philippines. This study was undertaken to determine the diversity of marine gastropods found in the intertidal of Dapya Island. Collection of specimens was done through hand picking and beachcombing methods in the three established study stations. Data revealed a total of 184 individuals belonging to 37 species in 5 orders, 15 families and 25 genera. The order Neogastropoda obtained the highest number of species with 15 species, followed by order Mesogastropoda with 10 species, order Archaeogastropoda with 7 species, order Neritopsina with 4 species and order Caenogastropoda. Among the 37 species, Nerita undata was the most abundant. Shannon-Weiner diversity index revealed that station 2 (H=1.193) obtained the highest species diversity, followed by station 3 (H= 1.103) and station 1 (H=1.063). The Bray-Curtis analysis of species composition showed two different clusters of habitat. Cluster 1 is composed of two related habitats joined by Stations 1 and 2 with Si= 54.26% and cluster 2 composed of Stations 3 and 1 with Si= 40.65%. Furthermore, among the 37 species, six of which were concordant in all study stations viz., Angaria delphinus, Astralium calcar, Conus miles, Lambis lambis, Euprotomus bulla and Canarium labiatum. The results of the study showed a low diversity of intertidal gastropods in Barangay Day-asan. The area is known to be the most gleaned by locals and it is been already disturbed due to overharvesting of gastropod species.","PeriodicalId":56207,"journal":{"name":"Ruhuna Journal of Science","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42109830","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}

引用次数: 1

Assessment of tree species resistance to air pollution around a metal-scrap recycling factory using air pollution tolerance index and anticipated performance index 使用空气污染耐受指数和预期性能指数评估金属废料回收厂周围的树种对空气污染的抵抗力

Ruhuna Journal of Science Pub Date : 2019-06-30 DOI: 10.4038/RJS.V10I1.51

S. Oyedeji, O. O. Agboola, Janet K. Oyekunle, D. A. Animasaun, P. Fatoba

{"title":"Assessment of tree species resistance to air pollution around a metal-scrap recycling factory using air pollution tolerance index and anticipated performance index","authors":"S. Oyedeji, O. O. Agboola, Janet K. Oyekunle, D. A. Animasaun, P. Fatoba","doi":"10.4038/RJS.V10I1.51","DOIUrl":"https://doi.org/10.4038/RJS.V10I1.51","url":null,"abstract":"Air pollution is one of the major global tribulations in many developing cities around the world. This study evaluates pollution resistances of Terminalia catappa, Anacardium occidentale and Tectona grandis growing around a metal scrap-recycling factory in Osun state, Nigeria using air pollution tolerance index and anticipated performance index with the view of recommending the species for greenbelt development in urban spaces. Biochemical parameters such as ascorbic acid, total chlorophyll, foliar extract pH and relative water content were analyzed in fresh leaves harvested from the tree species growing around the metal-scrap recycling factory (ES) and a relatively unpolluted control site (CS). Air pollution tolerance index (APTI) and anticipated performance index (API) were obtained from the results of biochemical variables. The results showed biochemical parameters (including ascorbic acid, total chlorophyll, foliar extract pH and relative water content) and APTI varied significantly (p A. occidentale (13.53) > T. grandis (13.17) with plants having a higher index at CS than at ES. All three-tree species had intermediate tolerance but T. catappa and A. occidentale were assessed as good performers while T. grandis performed moderately in polluted sites. The study recommended T. catappa and A. occidentale over T. grandis for use in developing greenbelts in urban centres especially in highly polluted areas, such as the vicinity of factories.","PeriodicalId":56207,"journal":{"name":"Ruhuna Journal of Science","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42619658","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}

引用次数: 0

Efficacy of Gum Arabic as an esculent film on shelf life extension of tomato (Solanum lycopersicum L) fruit 阿拉伯胶保鲜膜对番茄果实保鲜期的影响

Ruhuna Journal of Science Pub Date : 2019-06-30 DOI: 10.4038/RJS.V10I1.49

T. A. Fashanu, A. Oladiji, O. A. Peters

{"title":"Efficacy of Gum Arabic as an esculent film on shelf life extension of tomato (Solanum lycopersicum L) fruit","authors":"T. A. Fashanu, A. Oladiji, O. A. Peters","doi":"10.4038/RJS.V10I1.49","DOIUrl":"https://doi.org/10.4038/RJS.V10I1.49","url":null,"abstract":"Effect of Gum Arabic (GA) as a non-toxic outer layer to prolong the shelf-life of tomato was carried out in the present study. Tomatoes were coated with 0% (Control) (A), 5% w/v (B), 10% w/v (C), 15% w/v (D) and 20% w/v (E) GA and stored at ambient (33°C; 70%). The polygalacturonase and β-galacturonase activities were carried out. Weight loss, titratable acidity, pH, lycopene, β-Carotene and antioxidant property of the fruits were determined at day 0, 5, 10, 15 and 20 during the experimental duration. Results indicated that polygalacturonase activity ranged from 0.753-1.138 unit/mg, β-galacturonase activity ranged from 1.55-2.78 x 103 miller units, β-carotene ranged from 1.78-23.89 mg/g, antioxidant property ranged from 66.26-192.12μg/g, titratable acidity was from 0.595-0.95% while the lycopene ranged from 0.77-17.62 mg/g. These results showed that control had significant rapid weight loss with faster rate of softening while the tomatoes coated with GA demonstrated a significant (p<0.05) deferment in ripening as well as maintained its nutritional quality up to 20 days. This indicates that GA may be utilized as an edible coating for tomato. \u0000 \u0000Key words: Edible film, Gum Arabic, ripening, shelf life.","PeriodicalId":56207,"journal":{"name":"Ruhuna Journal of Science","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45912721","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}

引用次数: 3

Development of a novel and benign emulsion paint binder from epoxidized soybean oil and dimethylol urea blend 环氧大豆油与二甲基脲共混物制备新型良性乳胶漆粘合剂

Ruhuna Journal of Science Pub Date : 2019-06-30 DOI: 10.4038/RJS.V10I1.50

A. Akinterinwa, Sunday Ogwuche, Sunday A Osameahon, Abdulraheem Anumah

引用次数: 0

Types and frequency of fingerprint minutiae in individuals of Igbo and Yoruba ethnic groups of Nigeria 尼日利亚伊博族和约鲁巴族个体指纹细节的类型和频率

Ruhuna Journal of Science Pub Date : 2019-06-30 DOI: 10.4038/RJS.V10I1.52

U. U. Akpan, T. E. Awe, D. Idowu, Khalid Olajide Adekoya

{"title":"Types and frequency of fingerprint minutiae in individuals of Igbo and Yoruba ethnic groups of Nigeria","authors":"U. U. Akpan, T. E. Awe, D. Idowu, Khalid Olajide Adekoya","doi":"10.4038/RJS.V10I1.52","DOIUrl":"https://doi.org/10.4038/RJS.V10I1.52","url":null,"abstract":"The population distribution of fingerprint minutiae is necessary to improve efficiency of fingerprints in identifying individuals in a population-specific manner. The objective of the study was to determine the distribution of different types of minutiae fingerprint feature in two Nigerian ethnic populations. Fingerprints from forty-four (44) Igbo individuals and forty-four (44) Yoruba individuals, both of Nigeria were collected using a manual impression method that uses ink pad and paper. Of all the minutiae types considered, bifurcations and convergences accounted for 54.85% of the study’s total minutiae counts (TMC). This study shows that the Igbo ethnic group consistently have higher count of all minutiae types and higher total minutiae counts for both hands statistically significant at P<0.001. We found association between gender and minutiae distribution in some minutiae types including fragment/point or dot (FP), overlap (OL) and break (BR). This work revealed important variations among individuals from the two ethnic groups on the distribution and variability of minutiae in Nigeria populations. \u0000 \u0000Keywords: Dermatoglyphics, fingerprints, forensic, Igbo, minutiae, Nigeria, Yoruba.","PeriodicalId":56207,"journal":{"name":"Ruhuna Journal of Science","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44232049","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}

引用次数: 2

Potential of cow dung as insect herbivore repellent on Cowpea (Vigna unguiculata) 牛粪对豇豆的驱草潜力

Ruhuna Journal of Science Pub Date : 2019-06-30 DOI: 10.4038/RJS.V10I1.53

A. Ogunyebi, Amos Olubiyo, K. Omoyajowo, Tina Fingesi

{"title":"Potential of cow dung as insect herbivore repellent on Cowpea (Vigna unguiculata)","authors":"A. Ogunyebi, Amos Olubiyo, K. Omoyajowo, Tina Fingesi","doi":"10.4038/RJS.V10I1.53","DOIUrl":"https://doi.org/10.4038/RJS.V10I1.53","url":null,"abstract":"This study examined the potential of using cow dung as a repellent of herbivore pest on cowpea (Vigna unguiculata) and the work was carried out in the botanical and zoological garden of the University of Lagos, Akoka, Lagos, Nigeria. Four accessions of cowpea were grown in the soil samples collected from the Botanical and Zoological garden of the University of Lagos. The experiment was arranged in a randomized block design with three replicates to monitor the potential of using cow dung as a repellent of herbivore pest on cowpea for a period of six weeks. The data collected was analyzed using ANOVA. The results showed that cow dung treatments did not have significant effect at (P> 0.05) in repelling the insect of cowpeas. However, the plants treated with high concentrations of cow dung attracted significantly (P<0.05) higher number of insect pests and as the days of the application of the treatments increases, the number of leaves damaged by the insects increases. This study therefore recommends that a further study should be carried out using some other different plants species at different locations and under different environmental conditions. \u0000Keywords: Cow dung, cowpea, insect repellent","PeriodicalId":56207,"journal":{"name":"Ruhuna Journal of Science","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48069228","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}

引用次数: 0