African Scientific Reports最新文献

{"title":"Chemical and bioprotective studies of Xylopia aethiopica seed extract and molecular docking of doconexent and cryptopinone as the prominent compounds","authors":"O. U. Igwe, Cletus Christian Oru, I. Otuokere","doi":"10.46481/asr.2024.3.2.186","DOIUrl":"https://doi.org/10.46481/asr.2024.3.2.186","url":null,"abstract":"Fourteen phytochemical compounds were identified in the gas chromatography/mass spectrometry (GC/MS) analysis of the petroleum ether extract of the seeds of Xylopia aethiopica. The compounds comprised of terpenoids (56.027 %), unsaturated fatty acids (30.081 %), alcohol (9.385 %) and saturated fatty acid (4.507 %). The extract showed high antioxidant activity in a dose dependent pattern at a minimum and maximum concentrations of 25 and 400 μg/ml respectively and could be compared with that of ascorbic acid used as a standard antioxidant agent. The antibacterial activity screening of the extract against five pathogenic bacteria organisms indicated that the extract possessed more antibacterial activity than gentamicin used as a standard antibacterial agent. The trend of activity was Klebsiella pneumoniae (gram-negative) > Shigella flexneri (gram-negative) > Staphylococcus epidermidis (gram-positive) > Escherichia coli (gram-negative) > Streptococcus pneumoniae (gram-positive). The presence of high amount of terpenoids in the extract of X. aethiopica could be the reason for the high antioxidant and antibacterial activities shown by the extract and also suggests why the seed extract of the plant is used in herbal medicine for the treatment of diseases and infections. All of the test compounds had negative binding affinities, according to molecular docking modelling, indicating that the compounds had been successfully docked to the receptors. The compounds showed good pharmacokinetic properties, such as high blood-brain barrier absorption, oral bioavailability, and water solubility, in the in-silico ADME and drug-likeness predictions. The findings of this study significantly increase the relevance of these compounds as promising first targets for the treatment of drug resistant bacteria. This may help pharmacologists and other medicinal chemists create and synthesize even more potent drug candidates.","PeriodicalId":470488,"journal":{"name":"African Scientific Reports","volume":" 719","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141823859","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":"Radiotoxicity and groundwater quality for drinking in a multi-layered saline sedimentary terrain of Keana, Central Benue trough, Nigeria","authors":"N. Umar, S. Iyakwari","doi":"10.46481/asr.2024.3.2.169","DOIUrl":"https://doi.org/10.46481/asr.2024.3.2.169","url":null,"abstract":"The evaluation of uranium concentrations in the groundwater is therefore pertinent to advise on the known connection between the chemical and radiological toxicity of the element with some chronic lung cancer and kidney diseases. The activity concentrations in all the water samples vary from 372 to 19964 µgL-1 with the highest value in the AG borehole samples and the lowest in both the AB and AC samples respectively. The estimated Annual Effective Dose (AED) for all the age groups that rely on groundwater-based drinking varies from 0.012 to 0.991 mSvy-1 with the highest value of 0.991 mSvy-1 reported in sample AG for children age range from 7-12 years. The lifetime cancer mortality and morbidity risk due to 238U vary from 1.40 x 10-2 to 1.54 x 10-1 and 2.14 x10-2 to 8.60 x 10-1 respectively, with the highest value reported in the sample AG. All the values exceed the acceptable cancer risk value of 10-3 recommended by the United States Environmental Protection Agency (USEPA). The Lifetime Average Daily Dose (LADD) of 238U varies from 8.58 x 10-4 to 4.61 x 10-2 with the highest value of 4.61 x 10-2 μgkg‒1day‒1 noted in the sample AG. The LADD for all the samples is lower than the acceptable value of 0.6 × 10-1 μgkg‒ day‒1. Though the risk at some locations is close to the threshold value, thus the present concentration of 238U in the groundwater may pose a serious threat to the users unless adequate treatments are taken before consumption.","PeriodicalId":470488,"journal":{"name":"African Scientific Reports","volume":"68 16","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141651303","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":"Predicting the needs of people living with a disability using the two-level logit-skewed exponential power model","authors":"Abayomi Ajayi, Olaniyi Olayiwola, Fadeke Apantaku, Idowu Osinuga, Oluwaseun Wale-Orojo","doi":"10.46481/asr.2024.3.2.181","DOIUrl":"https://doi.org/10.46481/asr.2024.3.2.181","url":null,"abstract":"The impact of high cost of living and movement of medical personnel in Nigeria to other countries. has a major impact on families/households. These has affected Person’s living with disabilities (PLWD) with special needs which require regular visitation to clinic and additional expenses. Therefore this study proposed predictive models with generalized distributed (combination of normal and non-normal) error term under Two Stage Sampling. Data from the Nigeria Living Standard Survey (NLSS) 2018 on frequency of doctor’s visit and cost by households with difficulty in remembering were used. Logit Skewed Exponential Power (LSEP-II) were developed for two-level Random Effect Model using Bayesian framework. The parameters for LSEP-II were estimated using the Markov Chain Monte-Carlo (MCMC) algorithm with JAGS software. Cartograms were used to determine the spatial distribution for the proportion of doctor’s visit and cost using the predicted values. R-hat showed that the posterior distribution converges. The study revealed that Logit Skewed Exponential Power for two-level Random Effect Model modelled and predicted doctor’s visit and additional cost for PLWDs in two-Stage Stratified Random Sampling Design.","PeriodicalId":470488,"journal":{"name":"African Scientific Reports","volume":" 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141679701","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":"Bathymetric survey and volumetric analysis of Bakolori dam reservoir North West Nigeria","authors":"Ahmad Mahi Shuaibu","doi":"10.46481/asr.2024.3.2.154","DOIUrl":"https://doi.org/10.46481/asr.2024.3.2.154","url":null,"abstract":"Many approaches have been devised for measuring water depth in bathymetric surveys, which are used to assess sediment deposited directly in lakes and reservoirs. This technique is mostly used to calculate the reservoir's capacity and the amount of sedimentation that occurs there. The results of the volumetric analysis and bathymetric survey of the Bakolori Dam reservoir, which is situated in Northwestern Nigeria, are presented in this work. During this investigation, the differential Global Positioning System receiver (GPS), automatic level measuring tool, echo-sounder, and engine boat were utilized. ArcGis 10.0 was used to analyze the acquired data. In order to evaluate the reservoir capacity loss during the Bakolori reservoir's operating period as of 1983, the designed computed reservoir capacity was compared with the current bathymetry survey. At a spillway crest elevation of 334 meters above mean sea level (amsl), the reservoir's initial capacity is reported as 430 million cubic meters (MCM). However, the capacity has since been revised to 291 meters at the same level, with a volume change of 139,269,495 m3. As a result, the reservoir's volume changed by approximately 139 MCM during a thirty-five (35) year period of service, representing a loss of storage capacity, while the annual siltation rate was around 3,979,128 m3/a. This indicated that 33% of the reservoir's storage capacity had silted up. This is demonstrated by the aquatic weeds that have grown to a height of 334.21 meters on the lake's surface, rising from the lakebed. Therefore, to prevent total siltation, the dam reservoir needs to be adequately dredged.","PeriodicalId":470488,"journal":{"name":"African Scientific Reports","volume":" 46","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141367990","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":"Geothermal resource potentials estimation from the interpretation of aeromagnetic data over parts of Southwestern Nigeria","authors":"Emmanuel Ike, A. S. Oniku, S. Ezike, Maxwell Obia Kanu, Rodney Ewusi-Wilson","doi":"10.46481/asr.2024.3.1.179","DOIUrl":"https://doi.org/10.46481/asr.2024.3.1.179","url":null,"abstract":"In a bid to explore unconventional electricity generation sources and reduce effects of fossil fuels, this study evaluates geothermal resource potentials over parts of Southwestern Nigeria, precisely depth to the bottom of magnetic source (DBMS), heat flow, geothermal gradient and their relationships. Regional-residual anomaly separation was conducted, and spectral analysis was applied on the residual anomaly component of 14 aeromagnetic data sheets. Depth to the bottom of magnetic source varies between 1.87 and 6.26 km, with average value of 3.50 km, heat flow varies between 23.18 and 77.38 mWm−2, with average value of 43.79 mWm−2, while geothermal gradient varies between 9.27 and 30.95 oC/km with average value of 17.52 oC/km. Northcentral region has the highest heat flow (77.4 mWm−2), followed by Northeast (68.3 mWm−2), Southwest has the least (< 40.0 mWm−2) while Southeast has values in between the extremes. A comparison between the average heat flow and that of ‘thermally stable’ continental regions of the world (60 or 65) mW/m2 gives 72.98 or 67.37% respectively. The estimated heat is probably from mantle plumes, radioactive sources or heat generated from pressures within basements that are overlaid by thick thermally insulated sediments, hence hot magmatic fluid flows into fractured basement and cause hydrothermal alterations of surrounding rocks. Since most geodynamic operations depends on thermal structure of the earth’s crust, the result of this study has undoubtedly contributed significantly to the body of existing thermal knowledge and closed the information gap regarding crustal temperature distribution at depth in Southwest part of Nigeria and Nigeria in general.","PeriodicalId":470488,"journal":{"name":"African Scientific Reports","volume":"5 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140674123","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":"Temperature-dependent viscometry of baobab pectin (Adansonia digitata L.)","authors":"Shadreck Muyambo, J. Urombo","doi":"10.46481/asr.2024.3.1.146","DOIUrl":"https://doi.org/10.46481/asr.2024.3.1.146","url":null,"abstract":"This study uses the Arrhenius-type equation and the Frenkel-Eyring equation to evaluate the viscosity-temperature dependency of the baobab pectin (BoP) solution at 278.16-353.16 K. The viscosity parameters (apparent viscosity, ηA and intrinsic viscosity, [η]) were analysed for polymeric systems of WEp (pectin extracted using water), AEp (pectin extracted using acid), and Cp (citrus pectin, a control). A Vibro-viscometer was used to measure ηA, while [η] values were estimated from the Kuwara equation. The viscosity parameters decrease with an increase in temperature, though the effects were more pronounced in WEp than in AEp and Cp. Data from [η] indicated that activation energy Ea was higher for AEp (12.24 kJ/mol) and lower for WEp (10.18 kJ/mol). In contrast, the ηA data had a higher Ea for WEp (21.38 kJ/mol) and a lower Ea for Cp (16.49 kJ/mol). The ηA data showed a non-linear viscosity-temperature relationship, and the Vogel-Fulcher-Tammann-Hesse equation was used instead to relate the temperature dependency of BoP. The flow patterns of all pectin solutions showed positive entropy (ΔS + v ), positive enthalpy (ΔH+ v ), and negative Gibbs free energy (ΔG−v ). This revealed that the flow was disordered, dependent on temperature, and spontaneous. Overall, the viscous flow of WEp was more sensitive and less dependent on temperature compared to AEp and Cp.","PeriodicalId":470488,"journal":{"name":"African Scientific Reports","volume":"57 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139850695","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":"Temperature-dependent viscometry of baobab pectin (Adansonia digitata L.)","authors":"Shadreck Muyambo, J. Urombo","doi":"10.46481/asr.2024.3.1.146","DOIUrl":"https://doi.org/10.46481/asr.2024.3.1.146","url":null,"abstract":"This study uses the Arrhenius-type equation and the Frenkel-Eyring equation to evaluate the viscosity-temperature dependency of the baobab pectin (BoP) solution at 278.16-353.16 K. The viscosity parameters (apparent viscosity, ηA and intrinsic viscosity, [η]) were analysed for polymeric systems of WEp (pectin extracted using water), AEp (pectin extracted using acid), and Cp (citrus pectin, a control). A Vibro-viscometer was used to measure ηA, while [η] values were estimated from the Kuwara equation. The viscosity parameters decrease with an increase in temperature, though the effects were more pronounced in WEp than in AEp and Cp. Data from [η] indicated that activation energy Ea was higher for AEp (12.24 kJ/mol) and lower for WEp (10.18 kJ/mol). In contrast, the ηA data had a higher Ea for WEp (21.38 kJ/mol) and a lower Ea for Cp (16.49 kJ/mol). The ηA data showed a non-linear viscosity-temperature relationship, and the Vogel-Fulcher-Tammann-Hesse equation was used instead to relate the temperature dependency of BoP. The flow patterns of all pectin solutions showed positive entropy (ΔS + v ), positive enthalpy (ΔH+ v ), and negative Gibbs free energy (ΔG−v ). This revealed that the flow was disordered, dependent on temperature, and spontaneous. Overall, the viscous flow of WEp was more sensitive and less dependent on temperature compared to AEp and Cp.","PeriodicalId":470488,"journal":{"name":"African Scientific Reports","volume":" 11","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139791039","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":"Development of 3D flow diagnostic numerical simulator and rock property modelling for a homogeneous faulted reservoir","authors":"Surajo Muhammed Gwio, Ibrahim Ayuba, Umar Faruk Aminua","doi":"10.46481/asr.2024.3.1.167","DOIUrl":"https://doi.org/10.46481/asr.2024.3.1.167","url":null,"abstract":"Research has shown that faults, especially sealing faults, have become a barrier to flow. Flow diagnostics, on the other hand, are straightforward and controlled numerical flow experiments that are performed to examine a reservoir model, build links and offer rudimentary volume estimates as well as to quickly produce a qualitative representation of the reservoir’s flow patterns. To evaluate, assess, and validate reservoir models and production scenarios, the ’diagnostics’ module in the Matlab Reservoir Simulation Toolbox (MRST) provides a computationally less expensive alternative to running fully featured multiphase simulations. This is done to determine qualitatively regions for well placement to maximize hydrocarbon recovery. Monitoring flow fields, timelines, and tracers—neutral particles in the fluid that flow with the fluid—are all part of flow diagnostics. These techniques are used to determine volumetric communication between a pair of injector-producer wells, as well as flow patterns between injection-production wells and the arrival time between them. To create the grid, the simulation schedule, the wells, upscaling, arrival time computation, and flow diagnostics (drainage and sweep regions) were all done using the Matlab reservoir simulation toolbox (MRST) package by “Makemodel 3” on the data obtained from “SPE 10th comparative solution project” on the MRST package. This was done for a homogeneous anisotropic faulted porous medium. The simulation runs for about 473,739 milliseconds on a fine grid having 20040 active cells while in the coarse model with faster computational time of about 200 seconds, 112 milliseconds. At the early stages of the reservoir bottom-hole pressure for injector I1(about 7000psia) and three producers P1, P2 and P3 remains constant over time (about 3600psia) thanks to pressure support by I1. The extent of residence time after 10 years for the fine, coarse and more coarser model is that fluid element find it easier to transverse through the fault line from I1 to P1, P2 then P3 which takes lesser time than crossing across two intersecting faults, It can also be seen that the sweep efficiency of the fine grid is more effective than the coarse grid. Finally, it has been seen clearly that the fine grid model gives more accurate details but slower computational time while the coarse model which is less accurate but with faster computational time.","PeriodicalId":470488,"journal":{"name":"African Scientific Reports","volume":"53 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139812466","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":"Development of 3D flow diagnostic numerical simulator and rock property modelling for a homogeneous faulted reservoir","authors":"Surajo Muhammed Gwio, Ibrahim Ayuba, Umar Faruk Aminua","doi":"10.46481/asr.2024.3.1.167","DOIUrl":"https://doi.org/10.46481/asr.2024.3.1.167","url":null,"abstract":"Research has shown that faults, especially sealing faults, have become a barrier to flow. Flow diagnostics, on the other hand, are straightforward and controlled numerical flow experiments that are performed to examine a reservoir model, build links and offer rudimentary volume estimates as well as to quickly produce a qualitative representation of the reservoir’s flow patterns. To evaluate, assess, and validate reservoir models and production scenarios, the ’diagnostics’ module in the Matlab Reservoir Simulation Toolbox (MRST) provides a computationally less expensive alternative to running fully featured multiphase simulations. This is done to determine qualitatively regions for well placement to maximize hydrocarbon recovery. Monitoring flow fields, timelines, and tracers—neutral particles in the fluid that flow with the fluid—are all part of flow diagnostics. These techniques are used to determine volumetric communication between a pair of injector-producer wells, as well as flow patterns between injection-production wells and the arrival time between them. To create the grid, the simulation schedule, the wells, upscaling, arrival time computation, and flow diagnostics (drainage and sweep regions) were all done using the Matlab reservoir simulation toolbox (MRST) package by “Makemodel 3” on the data obtained from “SPE 10th comparative solution project” on the MRST package. This was done for a homogeneous anisotropic faulted porous medium. The simulation runs for about 473,739 milliseconds on a fine grid having 20040 active cells while in the coarse model with faster computational time of about 200 seconds, 112 milliseconds. At the early stages of the reservoir bottom-hole pressure for injector I1(about 7000psia) and three producers P1, P2 and P3 remains constant over time (about 3600psia) thanks to pressure support by I1. The extent of residence time after 10 years for the fine, coarse and more coarser model is that fluid element find it easier to transverse through the fault line from I1 to P1, P2 then P3 which takes lesser time than crossing across two intersecting faults, It can also be seen that the sweep efficiency of the fine grid is more effective than the coarse grid. Finally, it has been seen clearly that the fine grid model gives more accurate details but slower computational time while the coarse model which is less accurate but with faster computational time.","PeriodicalId":470488,"journal":{"name":"African Scientific Reports","volume":"45 10","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139872561","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":"Numerical simulation of a nonlinear diffusion type equation in a two phase media with linear porosity and permeability model","authors":"I. D. Dorothy, I. M. Echi, A. N. Amah","doi":"10.46481/asr.2024.3.1.119","DOIUrl":"https://doi.org/10.46481/asr.2024.3.1.119","url":null,"abstract":"Predicting and understanding the behavior of pressure is important in reservoir maintenance and evaluation. This work studies the behavior of fluid pressure in a reservoir by numerical simulation of the pressure diffusion type equation in a two phase media with a linear porosity and permeability model. Because the porosity and permeability are pressure dependent, the resulting diffusion type equation is nonlinear and is solved using a backward-forward finite difference method. The simulation code was ran using a constant porosity and permeability model and a linear porosity and permeability model. The results from the linear porosity and permeability model was compared to that of the constant porosity and permeability model. In both cases the pressure gradient was greatest at the wellbore and decreases as the radial distances away from the wellbore increases. The pressure in both cases also decreased with time. However, at each location and time the pressure drop was lower in the linear porosity and permeability model than with the constant porosity and permeability. The backward-forward finite difference method proved to be useful in solving numerically the nonlinear diffusion type equation. This work can be applied in the oil and gas industry to predict pressure behavior in reservoirs and make investment decisions, production and maintenance decision.","PeriodicalId":470488,"journal":{"name":"African Scientific Reports","volume":"37 42","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139684194","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}