Osaro Iyekowa, Felix Okieimen, Clifford O Ehisuoria
Sickle cell disease is a genetic blood disorder that affects the shape and transportation of the red blood cells (RBCs) in blood vessels, leading to various clinical complications. Available medicines for treating the disease are insufficiently effective, toxic or expensive. Therefore, there has been a pressing need for effective and inexpensive therapeutic agents from indigenous medicinal plants. Petiveria alliacea, Canna indica and Pergularia daemia, respectively were evaluated for their cationic constituents as a measure for their antisickling activity in sickle cell anaemia disorder. The three medicinal plants were extracted separately with methanol solvent using maceration method for 72 hours. The extracts were concentrated using a rotary evaporator (Model RE, 200, USA). Phytochemical screenings were conducted using standard method, while other portions of the extract were subjected to dry ash digestion for determination of mineral elements by emission flame photometry (EFP) and atomic absorption spectrophotometry (AAS). Evaluation of the antisickling activity of the extracts was done using the sodium metabisulphite (SMBS) test. Eugenol, terpenoids and alkaloids were present in the three plant extracts, while K+ values recorded for Petiveria alliacea, Canna indica and Pergularia daemia were 54.30 mg kg–1, 180.10 mg kg–1 and 28.30 mg kg–1, respectively. Other mineral elements detected in the three plants were Cu2+, Zn2+, Fe2+ and Mg2+. The leaves extract of Canna indica and Pergularia daemia at high dose of 300 µg/mL caused significant reductions of sickle red blood cells from 15% to 6% and 15% to 1%, respectively at 90 minutes of the antisickling test. The research confirmed that extracts of both Canna indica and Pergularia daemia used in this study have significant antisickling properties in invitro studies than Petiveria alliacea.
Keywords: Antisickling activity, Petiveria alliacea, Canna indica, Pergularia daemia, sickle cell, phytochemicals, minerals
{"title":"In-vitro Antisickling Activity of Pergularia daemia, Canna indica and Petiveria alliacea Plants used in the Treatment of Sickle Cell Anaemia in Edo State, Nigeria","authors":"Osaro Iyekowa, Felix Okieimen, Clifford O Ehisuoria","doi":"10.4314/tjs.v49i2.14","DOIUrl":"https://doi.org/10.4314/tjs.v49i2.14","url":null,"abstract":"Sickle cell disease is a genetic blood disorder that affects the shape and transportation of the red blood cells (RBCs) in blood vessels, leading to various clinical complications. Available medicines for treating the disease are insufficiently effective, toxic or expensive. Therefore, there has been a pressing need for effective and inexpensive therapeutic agents from indigenous medicinal plants. Petiveria alliacea, Canna indica and Pergularia daemia, respectively were evaluated for their cationic constituents as a measure for their antisickling activity in sickle cell anaemia disorder. The three medicinal plants were extracted separately with methanol solvent using maceration method for 72 hours. The extracts were concentrated using a rotary evaporator (Model RE, 200, USA). Phytochemical screenings were conducted using standard method, while other portions of the extract were subjected to dry ash digestion for determination of mineral elements by emission flame photometry (EFP) and atomic absorption spectrophotometry (AAS). Evaluation of the antisickling activity of the extracts was done using the sodium metabisulphite (SMBS) test. Eugenol, terpenoids and alkaloids were present in the three plant extracts, while K+ values recorded for Petiveria alliacea, Canna indica and Pergularia daemia were 54.30 mg kg–1, 180.10 mg kg–1 and 28.30 mg kg–1, respectively. Other mineral elements detected in the three plants were Cu2+, Zn2+, Fe2+ and Mg2+. The leaves extract of Canna indica and Pergularia daemia at high dose of 300 µg/mL caused significant reductions of sickle red blood cells from 15% to 6% and 15% to 1%, respectively at 90 minutes of the antisickling test. The research confirmed that extracts of both Canna indica and Pergularia daemia used in this study have significant antisickling properties in invitro studies than Petiveria alliacea.
 Keywords: Antisickling activity, Petiveria alliacea, Canna indica, Pergularia daemia, sickle cell, phytochemicals, minerals","PeriodicalId":22207,"journal":{"name":"Tanzania Journal of Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136370139","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}
Jestina V. Katandukila, Ackrey G. Sissa, Ginethon G. Mhaphi, Yeremia J. Chuhila, Fred D Chibwana
Leptospirosis is a neglected zoonotic disease, prominent in north-western Tanzania where interactions among humans, livestock and wildlife is high. This study therefore, assessed Leptospira seroprevalence and associated risk factors by screening Leptospira serovars from blood sera of cattle, goats and humans in Ngara and Kibondo Districts using Microscopic Agglutination Test (MAT). Blood sera were positive for seven Leptospira serovars in which Sokoine, Sejroe and Grippotyhposa had higher seropositivity of ≥ 20.9%, whereas Leptospira serovars Kenya, Pomona, Lora, and Bataviae had seropositivity of < 10%. Variation of seropositivity and seroprevalence between Ngara and Kibondo Districts was insignificant (p = 0.0718) but varied significantly between humans, goats and cattle (p = 0.0183). Leptospira serovars Sejroe and Grippotyphosa were present in humans, goats and cattle. Sokoine, Pomona and Bataviae were co-positive in humans and goats, while serovars Kenya and Lora were co-positive in humans and cattle, indicating the possibility of dualistic transmission of Leptospira serovars in the ecosystem. Suggested risk factors associated with acquiring Leptospira bacteria were drinking contaminated water, feeding contaminated food and farming in contaminated soils. Prevalence of Leptospira in the current study alerts for health and economic risks in north-western Tanzania, which requires intensive education programs on leptospirosis transmission and avoidance.
{"title":"Leptospira Serovars Circulating Among Human, Cattle and Goats with Associated Risk Factors in Ngara and Kibondo Districts, North-Western Tanzania","authors":"Jestina V. Katandukila, Ackrey G. Sissa, Ginethon G. Mhaphi, Yeremia J. Chuhila, Fred D Chibwana","doi":"10.4314/tjs.v49i2.10","DOIUrl":"https://doi.org/10.4314/tjs.v49i2.10","url":null,"abstract":"Leptospirosis is a neglected zoonotic disease, prominent in north-western Tanzania where interactions among humans, livestock and wildlife is high. This study therefore, assessed Leptospira seroprevalence and associated risk factors by screening Leptospira serovars from blood sera of cattle, goats and humans in Ngara and Kibondo Districts using Microscopic Agglutination Test (MAT). Blood sera were positive for seven Leptospira serovars in which Sokoine, Sejroe and Grippotyhposa had higher seropositivity of ≥ 20.9%, whereas Leptospira serovars Kenya, Pomona, Lora, and Bataviae had seropositivity of < 10%. Variation of seropositivity and seroprevalence between Ngara and Kibondo Districts was insignificant (p = 0.0718) but varied significantly between humans, goats and cattle (p = 0.0183). Leptospira serovars Sejroe and Grippotyphosa were present in humans, goats and cattle. Sokoine, Pomona and Bataviae were co-positive in humans and goats, while serovars Kenya and Lora were co-positive in humans and cattle, indicating the possibility of dualistic transmission of Leptospira serovars in the ecosystem. Suggested risk factors associated with acquiring Leptospira bacteria were drinking contaminated water, feeding contaminated food and farming in contaminated soils. Prevalence of Leptospira in the current study alerts for health and economic risks in north-western Tanzania, which requires intensive education programs on leptospirosis transmission and avoidance.
","PeriodicalId":22207,"journal":{"name":"Tanzania Journal of Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136370143","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}
Swaleh Tusiime, Karidewa Nyeinga, Denis Okello, Ole J. Nydal
Thermal energy storage (TES) systems enhance the use of solar energy for cooking by matching the energy demand to its supply. Useful energy is extracted from TES systems that are thermally stratified and this is enhanced when charged at an averagely constant-temperature. This paper presents an experimental analysis of a mechanical-thermostat used to control the charging of an oil based TES system. The thermostat consisted of a slider-valve, an expansion-system acting both as a thermal-sensor and actuator, and an adjusting-knob for setting the charging temperature. Oil from a cold-oil reservoir flows by gravity into a heating-chamber when a manual valve is opened. In the heating-chamber, the oil is heated causing the oil to expand triggering the opening of the slider-valve at a preset temperature. This allows the hot-oil to flow into the TES system at the set temperature. The thermostat was demonstrated for charging a TES system at preset temperatures of 116 °C, 150 °C, 200 °C and 230 °C. The volume of hot-oil delivered into a TES tank decreased with increasing charging temperature. The observed temperature variations were minimized by reducing the oil flow-rate using a valve hence achieving a fairly stable charging temperature.
{"title":"Thermal Performance of a Mechanical Thermostat for Charging an Energy Storage System","authors":"Swaleh Tusiime, Karidewa Nyeinga, Denis Okello, Ole J. Nydal","doi":"10.4314/tjs.v49i2.1","DOIUrl":"https://doi.org/10.4314/tjs.v49i2.1","url":null,"abstract":"Thermal energy storage (TES) systems enhance the use of solar energy for cooking by matching the energy demand to its supply. Useful energy is extracted from TES systems that are thermally stratified and this is enhanced when charged at an averagely constant-temperature. This paper presents an experimental analysis of a mechanical-thermostat used to control the charging of an oil based TES system. The thermostat consisted of a slider-valve, an expansion-system acting both as a thermal-sensor and actuator, and an adjusting-knob for setting the charging temperature. Oil from a cold-oil reservoir flows by gravity into a heating-chamber when a manual valve is opened. In the heating-chamber, the oil is heated causing the oil to expand triggering the opening of the slider-valve at a preset temperature. This allows the hot-oil to flow into the TES system at the set temperature. The thermostat was demonstrated for charging a TES system at preset temperatures of 116 °C, 150 °C, 200 °C and 230 °C. The volume of hot-oil delivered into a TES tank decreased with increasing charging temperature. The observed temperature variations were minimized by reducing the oil flow-rate using a valve hence achieving a fairly stable charging temperature.","PeriodicalId":22207,"journal":{"name":"Tanzania Journal of Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136370289","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}
Land use land cover (LULC) changes affect the planet's energy balance and region's climate. Land Surface Temperature (LST) is a vital indicator of this change. Studies in Dar es Salaam Metropolitan City have investigated LST and its relationships with building heights and densities, urban heat islands, spectral indices, and urban morphological determinants. The present study used cross-sectional profiles, chord diagrams, and simple linear regression models to examine the influence of LULC changes on the LST in Dar es Salaam Metropolitan City (DMC). LST was extracted from Landsat 5 TM and 8 OLI/TIRS images for 1995, 2009, and 2017. LULC was identified via the supervised random forest classification algorithm. Between 1995 and 2017, built-up areas rose by 8%, vegetation fell 7%, and bare soil 3%. As a result, the average LST rose by 3 °C. Built-up areas had the highest temperatures (24–26.5 °C), followed by bare soil (22–25.5 °C). The lowest temperatures (21–25 °C) were on vegetation and water. Built-up area positively correlated with LST, while vegetation, water bodies, and bare soil negatively correlated. The study results can assist local authorities in enforcing urban planning regulations, raising public awareness, and guiding policymakers in creating sustainable planning and management strategies for the future.
Keywords: Dar es Salaam, Land use land cover, simple linear regression model, land surface temperature, chord diagrams
{"title":"Influence of Urban Land Use Land Cover Changes on Land Surface Temperature in Dar es Salaam Metropolitan City, Tanzania: The Use of Geospatial Approach","authors":"Simon, Olipa, Lyimo, James, Yamungu, Nestory","doi":"10.4314/tjs.v49i2.7","DOIUrl":"https://doi.org/10.4314/tjs.v49i2.7","url":null,"abstract":"Land use land cover (LULC) changes affect the planet's energy balance and region's climate. Land Surface Temperature (LST) is a vital indicator of this change. Studies in Dar es Salaam Metropolitan City have investigated LST and its relationships with building heights and densities, urban heat islands, spectral indices, and urban morphological determinants. The present study used cross-sectional profiles, chord diagrams, and simple linear regression models to examine the influence of LULC changes on the LST in Dar es Salaam Metropolitan City (DMC). LST was extracted from Landsat 5 TM and 8 OLI/TIRS images for 1995, 2009, and 2017. LULC was identified via the supervised random forest classification algorithm. Between 1995 and 2017, built-up areas rose by 8%, vegetation fell 7%, and bare soil 3%. As a result, the average LST rose by 3 °C. Built-up areas had the highest temperatures (24–26.5 °C), followed by bare soil (22–25.5 °C). The lowest temperatures (21–25 °C) were on vegetation and water. Built-up area positively correlated with LST, while vegetation, water bodies, and bare soil negatively correlated. The study results can assist local authorities in enforcing urban planning regulations, raising public awareness, and guiding policymakers in creating sustainable planning and management strategies for the future.
 Keywords: Dar es Salaam, Land use land cover, simple linear regression model, land surface temperature, chord diagrams","PeriodicalId":22207,"journal":{"name":"Tanzania Journal of Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136066550","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}
Winifrida L Mbilinyi, Cyrus Rumisha, Augustine W Mwandya, George M Msalya
Nile tilapia farmers in Tanzania have been complaining about slow growth and low yields. Since some farmers obtain their seeds from unreliable sources, they may potentially be dealing with various non-targeted tilapias that require different environments and treatments to enhance growth and yields. Thus, this study analysed fragments (600 base pairs) of the cytochrome oxidase subunit I gene (COI) from 74 farmed tilapias in Kilosa and Kibaha, Tanzania to determine the presence of non-targeted tilapias. An additional 42 samples from the Magadu Fish Farm, Mindu dam, and Lake Victoria were included for comparison. The findings revealed that non-targeted tilapias accounted for 22.22–31.41% of the farmed stock, supporting the hypothesis that farmers are unknowingly dealing with a variety of non-targeted tilapias. Furthermore, pairwise FST comparison indicated genetic relatedness among the farmed fish, suggesting the sharing of fingerlings from the same broodstock or collection from the same wild locality. Therefore, farmers are advised to ensure they source seeds from certified hatcheries to minimize the risk of stocking non-targeted species. Additionally, due to the observed low genetic diversity in Kilosa samples, it is recommended that the country should establish a national breeding program for tilapia to provide farmers with access to high-quality seeds.
{"title":"Genetic Analysis Reveals Substantial Proportion of Non-targeted Tilapias among Farmed Stocks in Kilosa and Kibaha, Tanzania","authors":"Winifrida L Mbilinyi, Cyrus Rumisha, Augustine W Mwandya, George M Msalya","doi":"10.4314/tjs.v49i2.24","DOIUrl":"https://doi.org/10.4314/tjs.v49i2.24","url":null,"abstract":"Nile tilapia farmers in Tanzania have been complaining about slow growth and low yields. Since some farmers obtain their seeds from unreliable sources, they may potentially be dealing with various non-targeted tilapias that require different environments and treatments to enhance growth and yields. Thus, this study analysed fragments (600 base pairs) of the cytochrome oxidase subunit I gene (COI) from 74 farmed tilapias in Kilosa and Kibaha, Tanzania to determine the presence of non-targeted tilapias. An additional 42 samples from the Magadu Fish Farm, Mindu dam, and Lake Victoria were included for comparison. The findings revealed that non-targeted tilapias accounted for 22.22–31.41% of the farmed stock, supporting the hypothesis that farmers are unknowingly dealing with a variety of non-targeted tilapias. Furthermore, pairwise FST comparison indicated genetic relatedness among the farmed fish, suggesting the sharing of fingerlings from the same broodstock or collection from the same wild locality. Therefore, farmers are advised to ensure they source seeds from certified hatcheries to minimize the risk of stocking non-targeted species. Additionally, due to the observed low genetic diversity in Kilosa samples, it is recommended that the country should establish a national breeding program for tilapia to provide farmers with access to high-quality seeds.","PeriodicalId":22207,"journal":{"name":"Tanzania Journal of Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136370135","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}
Paul M. Omary, Emanuel X. Ricky, Naswibu A. Kasimu, M. Madirisha, K. Kilulya, E. Lugwisha
Drilling the wellbore into subsurface formations is the earliest stage in the life of a well that requires a suitable drilling fluid with good rheological and filtration control characteristics to achieve a successful drilling operation. This paper reports on the formulation of water-based drilling mud using kaolin clay reinforced with biopolymer, surfactant, and limestone from Tanzania. The raw materials used for the formulation were characterized using XRD, XRF, FTIR, and TGA techniques. The rheological properties, filtration loss, pH, and density of the formulated mud were measured using a viscometer, filter press, pH meter, and mud balance, respectively. The XRD results revealed kaolinite and quartz as the main minerals in all kaolin clay samples which were in agreement with the FTIR findings. The mineralogical composition of the kaolin was observed to vary with the mining sites and influenced the rheological and filtration control characteristics of the mud. The beneficiated drilling mud showed better rheological and filtration control characteristics than the commercially available bentonite mud in Dar es Salaam market and was comparable with the API standards. These results, therefore, are not only new but rather important and novel information on the potential of kaolin clay for the formulation of water based drilling mud. Keywords: Water-based drilling mud, kaolin clay, biopolymers, bentonite, surfactant
{"title":"Potential of Kaolin Clay on Formulation of Water Based Drilling Mud Reinforced with Biopolymer, Surfactant, and Limestone","authors":"Paul M. Omary, Emanuel X. Ricky, Naswibu A. Kasimu, M. Madirisha, K. Kilulya, E. Lugwisha","doi":"10.4314/tjs.v49i1.19","DOIUrl":"https://doi.org/10.4314/tjs.v49i1.19","url":null,"abstract":"Drilling the wellbore into subsurface formations is the earliest stage in the life of a well that requires a suitable drilling fluid with good rheological and filtration control characteristics to achieve a successful drilling operation. This paper reports on the formulation of water-based drilling mud using kaolin clay reinforced with biopolymer, surfactant, and limestone from Tanzania. The raw materials used for the formulation were characterized using XRD, XRF, FTIR, and TGA techniques. The rheological properties, filtration loss, pH, and density of the formulated mud were measured using a viscometer, filter press, pH meter, and mud balance, respectively. The XRD results revealed kaolinite and quartz as the main minerals in all kaolin clay samples which were in agreement with the FTIR findings. The mineralogical composition of the kaolin was observed to vary with the mining sites and influenced the rheological and filtration control characteristics of the mud. The beneficiated drilling mud showed better rheological and filtration control characteristics than the commercially available bentonite mud in Dar es Salaam market and was comparable with the API standards. These results, therefore, are not only new but rather important and novel information on the potential of kaolin clay for the formulation of water based drilling mud. \u0000Keywords: Water-based drilling mud, kaolin clay, biopolymers, bentonite, surfactant","PeriodicalId":22207,"journal":{"name":"Tanzania Journal of Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79324651","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}
The increased penetration of distributed energy resources (DERs) technologies to residential users has fostered the need for DERs integration and control methods in the secondary distribution networks (SDN). In order to reap the potential advantages of DERs and achieve their inclusion in the electrical power system while avoiding their negative impacts, the DERs should be optimally placed and sized. Considering the nature of electrical networks and DER operations, the DERs placement is a nondeterministic polynomial hard (NP-hard) optimization problem. Metaheuristic algorithms are efficient for solving DER placement problems. Metaheuristic algorithms for DER placement in SDN involve high computational effort, theoretical convergence assumptions that cannot be satisfied in the real world and dependence on parameter settings. Therefore, this study proposes a DER placement algorithm that employs a cloud-based model symbiotic organism search algorithm (CMSOS). The CMSOS is attributed to simple implementation and computation, good convergence, and parameter independence. The electrical network segment taken for Tanzania’s electrical distribution network was used for testing the algorithms, considering power loss and voltage deviations. Results show that using DERs in the proposed locations reduces power loss by 89.3%. The convergence profile shows that the proposed CMSOS-based algorithm converges faster than the conventional symbiotic organism search algorithm (SOS). Keywords: Metaheuristic Algorithms, Symbiotic Organism Search, DER Placements, Radial Distribution Network, Cloud-based model
{"title":"A Cloud Based Model Symbiotic Organism Search Algorithm for Placement of Distributed Energy Resources in the Electrical Secondary Distribution Networks","authors":"Shamte Kawambwa, Daudi Mnyanghwalo","doi":"10.4314/tjs.v49i1.6","DOIUrl":"https://doi.org/10.4314/tjs.v49i1.6","url":null,"abstract":"The increased penetration of distributed energy resources (DERs) technologies to residential users has fostered the need for DERs integration and control methods in the secondary distribution networks (SDN). In order to reap the potential advantages of DERs and achieve their inclusion in the electrical power system while avoiding their negative impacts, the DERs should be optimally placed and sized. Considering the nature of electrical networks and DER operations, the DERs placement is a nondeterministic polynomial hard (NP-hard) optimization problem. Metaheuristic algorithms are efficient for solving DER placement problems. Metaheuristic algorithms for DER placement in SDN involve high computational effort, theoretical convergence assumptions that cannot be satisfied in the real world and dependence on parameter settings. Therefore, this study proposes a DER placement algorithm that employs a cloud-based model symbiotic organism search algorithm (CMSOS). The CMSOS is attributed to simple implementation and computation, good convergence, and parameter independence. The electrical network segment taken for Tanzania’s electrical distribution network was used for testing the algorithms, considering power loss and voltage deviations. Results show that using DERs in the proposed locations reduces power loss by 89.3%. The convergence profile shows that the proposed CMSOS-based algorithm converges faster than the conventional symbiotic organism search algorithm (SOS). \u0000Keywords: Metaheuristic Algorithms, Symbiotic Organism Search, DER Placements, Radial Distribution Network, Cloud-based model","PeriodicalId":22207,"journal":{"name":"Tanzania Journal of Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87892658","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}
The fast generation of images in Electrical Capacitance Tomography (ECT) systems is a desirable feature for many industrial applications. Non-iterative reconstruction algorithms which qualify for this requirement generate poor-quality images. The Linear Back Projection (LBP) is the fastest non-iterative reconstruction algorithm. The challenge is to find a technique to improve the quality of images from LBP at a low computational cost. Image enhancement techniques have been investigated for improving the quality of images reconstructed from the LBP algorithm. Simulated and measured static and dynamic flow data were used in the evaluation. The performance results were benchmarked with results from the Projected Land Weber (PLW) one of the accurate iterative reconstruction algorithms. The Gompertz enhancement algorithm was found to have 3.5 times more computation cost than the LBP reconstruction algorithm and the accuracy of the iterative PLW reconstruction algorithm. This is noteworthy since the algorithm does achieve a good balance between accuracy and speed. The fact that the accuracy gained satisfies the reservoir management standards in the multiphase hydrocarbon production sector is significant in this regard. Keywords: Electrical Capacitance tomography, Multiphase flow imaging, Maximum entropy thresholding, Gompertz distribution, Image enhancement
{"title":"Evaluation of Image Enhancement Techniques for Electrical Capacitance Tomography Applications","authors":"A. Mwambela","doi":"10.4314/tjs.v49i1.11","DOIUrl":"https://doi.org/10.4314/tjs.v49i1.11","url":null,"abstract":"The fast generation of images in Electrical Capacitance Tomography (ECT) systems is a desirable feature for many industrial applications. Non-iterative reconstruction algorithms which qualify for this requirement generate poor-quality images. The Linear Back Projection (LBP) is the fastest non-iterative reconstruction algorithm. The challenge is to find a technique to improve the quality of images from LBP at a low computational cost. Image enhancement techniques have been investigated for improving the quality of images reconstructed from the LBP algorithm. Simulated and measured static and dynamic flow data were used in the evaluation. The performance results were benchmarked with results from the Projected Land Weber (PLW) one of the accurate iterative reconstruction algorithms. The Gompertz enhancement algorithm was found to have 3.5 times more computation cost than the LBP reconstruction algorithm and the accuracy of the iterative PLW reconstruction algorithm. This is noteworthy since the algorithm does achieve a good balance between accuracy and speed. The fact that the accuracy gained satisfies the reservoir management standards in the multiphase hydrocarbon production sector is significant in this regard. \u0000Keywords: Electrical Capacitance tomography, Multiphase flow imaging, Maximum entropy thresholding, Gompertz distribution, Image enhancement","PeriodicalId":22207,"journal":{"name":"Tanzania Journal of Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80540906","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}
E. H. Alhassan, S. Osei, A. Ampofo-Yeboah, S. O. Dandi
The goal of this study was to assess common endoparasites on Tilapia zillii in the Tono Reservoir, as well as to investigate the mean intensity and prevalence of these parasites. A total of 175 fish specimens were examined during the study. Endoparasites of three metazoans and one protozoan were observed from the Tilapia zillii gills, intestines, and stomach. The findings showed that the most common endoparasites affecting Tilapia zillii are Ichthyopthirius multifiliis, Bothriocephalus sp., Contracaecum sp., and Dactylogyrus sp. Also, Contracaecum sp had the highest prevalence of 29.71, followed by Bothriocephalus sp (18.86), Ichthyopthirius multifiliis (12), and Dactylogyrus sp (6.86). The average quantity of Bothriocephalus sp was 0.84, Contracaecum sp was 1.33, Dactylogyrus sp was 0.31, and Ichthyopthirius multifiliis was 0.54. The reservoir's physicochemical parameters changed every month due to inflows and other runoffs joining. Low levels of these parameters were discovered to influence the prevalence and distribution of these parasites. Haematological parameters showed significant changes between the adult and fingerling groups, where it was observed an improvement in health status in the adult group. It was also observed that fingerlings (0.1–20 g) were more infected, which significantly affected their blood profile. Keywords: Tilapia zillii, endoparasite, blood profile, pathogenic effects, environmental stress
{"title":"Prevalence of Endoparasites and Haematology in Redbelly Tilapia from a Shallow Tropical Reservoir in Ghana","authors":"E. H. Alhassan, S. Osei, A. Ampofo-Yeboah, S. O. Dandi","doi":"10.4314/tjs.v49i1.2","DOIUrl":"https://doi.org/10.4314/tjs.v49i1.2","url":null,"abstract":"The goal of this study was to assess common endoparasites on Tilapia zillii in the Tono Reservoir, as well as to investigate the mean intensity and prevalence of these parasites. A total of 175 fish specimens were examined during the study. Endoparasites of three metazoans and one protozoan were observed from the Tilapia zillii gills, intestines, and stomach. The findings showed that the most common endoparasites affecting Tilapia zillii are Ichthyopthirius multifiliis, Bothriocephalus sp., Contracaecum sp., and Dactylogyrus sp. Also, Contracaecum sp had the highest prevalence of 29.71, followed by Bothriocephalus sp (18.86), Ichthyopthirius multifiliis (12), and Dactylogyrus sp (6.86). The average quantity of Bothriocephalus sp was 0.84, Contracaecum sp was 1.33, Dactylogyrus sp was 0.31, and Ichthyopthirius multifiliis was 0.54. The reservoir's physicochemical parameters changed every month due to inflows and other runoffs joining. Low levels of these parameters were discovered to influence the prevalence and distribution of these parasites. Haematological parameters showed significant changes between the adult and fingerling groups, where it was observed an improvement in health status in the adult group. It was also observed that fingerlings (0.1–20 g) were more infected, which significantly affected their blood profile. \u0000Keywords: Tilapia zillii, endoparasite, blood profile, pathogenic effects, environmental stress","PeriodicalId":22207,"journal":{"name":"Tanzania Journal of Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88563595","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}
D. N. Katongole, Karidewa Nyeinga, D. Okello, D. Mukiibi, J. Mubiru, Yeeko Kisira
The paper presents an analysis of spatial and temporal solar potential variations in Uganda. The solar radiation potential distribution was investigated based on measured data from 56 ground meteorological stations across Uganda from January 2015 to February 2022. The data were recorded after every 5-minute interval. The monthly average daily Global Horizontal Irradiance (GHI) was analysed using the spatial inverse distance weighting (IDW) interpolation technique in ArcGIS 10.7.1. The GHI distribution was found to have maxima at equinox and minimum between June and July. The average global horizontal irradiation is found to be 1680 KWh per year, with a daily variability below 10%. This is above the threshold for solar energy applications and with such low variability, large scale solar PV plants can be installed with minimum backup requirements. Northern Uganda receives the highest average daily global horizontal irradiation of 5.38 Whm–2 day–1, while Western Uganda receives 4.16 Whm–2 day–1, the lowest. The average AM/PM ratio depicted a value above 2 for all regions in Uganda and therefore, optimal solar energy exploitation for fixed systems favours eastern orientation. The central, eastern and northern Uganda which is 69.3% of the country has relief favourable for large scale solar PV power plants and CSP facilities. Keywords: GHI, IDW, Global solar radiation, Solar insolation, PV power plants, Uganda
{"title":"Spatial and Temporal Solar Potential Variation Analysis in Uganda Using Measured Data","authors":"D. N. Katongole, Karidewa Nyeinga, D. Okello, D. Mukiibi, J. Mubiru, Yeeko Kisira","doi":"10.4314/tjs.v49i1.1","DOIUrl":"https://doi.org/10.4314/tjs.v49i1.1","url":null,"abstract":"The paper presents an analysis of spatial and temporal solar potential variations in Uganda. The solar radiation potential distribution was investigated based on measured data from 56 ground meteorological stations across Uganda from January 2015 to February 2022. The data were recorded after every 5-minute interval. The monthly average daily Global Horizontal Irradiance (GHI) was analysed using the spatial inverse distance weighting (IDW) interpolation technique in ArcGIS 10.7.1. The GHI distribution was found to have maxima at equinox and minimum between June and July. The average global horizontal irradiation is found to be 1680 KWh per year, with a daily variability below 10%. This is above the threshold for solar energy applications and with such low variability, large scale solar PV plants can be installed with minimum backup requirements. Northern Uganda receives the highest average daily global horizontal irradiation of 5.38 Whm–2 day–1, while Western Uganda receives 4.16 Whm–2 day–1, the lowest. The average AM/PM ratio depicted a value above 2 for all regions in Uganda and therefore, optimal solar energy exploitation for fixed systems favours eastern orientation. The central, eastern and northern Uganda which is 69.3% of the country has relief favourable for large scale solar PV power plants and CSP facilities. \u0000Keywords: GHI, IDW, Global solar radiation, Solar insolation, PV power plants, Uganda","PeriodicalId":22207,"journal":{"name":"Tanzania Journal of Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76124332","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}
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