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Open Journal of Obstetrics and Gynecology 2021年第4期11卷 461-473页

作者： Akintunde Olusegun Fehintola Olufemi Timothy Awotunde Olumuyiwa Ayotunde Ogunlaja Lawrence Olujire Olujide Samuel Eniola Akinola sunday adekunle oladeji Babatola Bakare Olurotimi Idowu Aaron Department of Obstetrics Gynaecology and Perinatology Obafemi Awolowo University Ile-Ife Osun State Nigeria Department of Obstetrics and Gynaecology Bowen University Teaching Hospital Ogbomoso Oyo State Nigeria Department of Obstetrics and Gynaecology Royal Hampshire County Hospital Winchester UK Department of Obstetrics & Gynaecology Unimed Teaching Hospital Ondo Ondo State Nigeria Department of Anaesthesia Obafemi Awolowo University Ile-Ife Osun State Nigeria

Background: Symptomatic pelvic organ prolapse (POP) impacts the sufferers’ quality of life negatively. There is a preference for a mechanical device in certain conditions though the definitive management of POP is surgical. Objectives: We conducted the study to evaluate the outcome of management of POP using mechanical devices. Methods: It was a prospective study. It took place in the gynecology unit of the Bowen University Teaching Hospital Ogbomoso between May 2014 and April 2019. We followed up with eligible patients who opted for pessary use for a median duration of 18 months (Range 12 - 84 months). We excluded those who refuse to participate in the study. Results: Of the 127 patients with symptomatic POP, seventy-five (59.1%) opted for the use of mechanical devices, and 70 successfully retained them four weeks after insertion. We lost Six (9.2%) patients to follow up. Of the 64 women included in the analysis, 16 (25%) discontinued use at so

关键词： Mechanical Device Symptomatic Pelvic Organ Prolapse Complications Dis-continuation

Lead exposure increases oxidative stress in the gastric mucosa of HCl/ethanol-exposed rats

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World Journal of Gastroenterology 2007年第38期13卷 5121-5126页

作者： Samuel Babafemi Olaleye Oluwatosin adekunle Adaramoye Perebiri Peter Erigbali Olasupo sunday Adeniyi Department of Physiology College of Medicine University of Ibadan Ibadan Nigeria Department of Biochemistry College of Medicine University of Ibadan Ibadan Nigeria

AIM: To investigate the role of reactive oxygen species in the ulcer-aggravating effect of lead in albino rats. METHODS: Albino Wistar rats were randomly divided into three groups and treated orally with 100 mg/L (low dose) or 5000 mg/L (high dose) of lead acetate for 15 wk. A third group received saline and served as control. At the end of wk 15, colorimetric assays were applied to determine the concentrations of total protein and nitrite, the activities of the oxidative enzymes catalase and superoxide dismutase, and lipid peroxidation in homogenized gastric mucosal samples. RESULTS: Exposure of rats to lead significantly increased the gastric mucosal damage caused by acidified ethanol. Although the basal gastric acid secretory rate was not significantly altered, the maximal response of the stomach to histamine was significantly higher in the lead-exposed animals than in the unexposed control group. Exposure to low and high levels of lead significantly increased gastric lipid peroxidation to 183.2% ± 12.7% and 226.1% ± 6.8% of control values respectively (P < 0.0). On the other hand, lead exposure significantly decreased catalase and superoxide dismutase (SOD) activities and the amount of nitrite in gastric mucosal samples. CONCLUSION: Lead increases the formation of gastric ulcers by interfering with the oxidative metabolism in the stomach.

关键词： Lead Ulcer Lipid peroxidation Catalase Gastric acid

A Novel Insertion Solution for the Travelling Salesman Problem

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Computers, Materials & Continua 2024年第4期79卷 1581-1597页

作者： Emmanuel Oluwatobi Asani Aderemi Elisha Okeyinka sunday Adeola Ajagbe Ayodele Ariyo Adebiyi Roseline Oluwaseun Ogundokun Temitope Samson adekunle Pragasen Mudali Matthew Olusegun Adigun Department of Computer Science Landmark UniversityOmu Aran251103Nigeria SDG 11 Group Landmark UniversityOmu Aran251103Nigeria Department of Computing MiVA UniversityAbuja900211Nigeria Department of Computer Science Ibrahim Badamasi Babangida UniversityLapai911101Nigeria Department of Computer Science University of ZululandKwadlangezwa3886South Africa Department of Computer&Industrial Production Engineering First Technical UniversityIbadan200243Nigeria Department of Multimedia Engineering Kaunas University of TechnologyKaunasLT-44249Lithuania Department of Computer Science Colorado State UniversityFort Collins80523USA

The studypresents theHalfMax InsertionHeuristic (HMIH) as a novel approach to solving theTravelling SalesmanProblem (TSP). The goal is to outperform existing techniques such as the Farthest Insertion Heuristic (FIH) andNearest Neighbour Heuristic (NNH). The paper discusses the limitations of current construction tour heuristics,focusing particularly on the significant margin of error in FIH. It then proposes HMIH as an alternative thatminimizes the increase in tour distance and includes more nodes. HMIH improves tour quality by starting withan initial tour consisting of a ‘minimum’ polygon and iteratively adding nodes using our novel Half Max *** paper thoroughly examines and compares HMIH with FIH and NNH via rigorous testing on standard TSPbenchmarks. The results indicate that HMIH consistently delivers superior performance, particularly with respectto tour cost and computational efficiency. HMIH’s tours were sometimes 16% shorter than those generated by FIHand NNH, showcasing its potential and value as a novel benchmark for TSP solutions. The study used statisticalmethods, including Friedman’s Non-parametric Test, to validate the performance of HMIH over FIH and *** guarantees that the identified advantages are statistically significant and consistent in various situations. Thiscomprehensive analysis emphasizes the reliability and efficiency of the heuristic, making a compelling case for itsuse in solving TSP issues. The research shows that, in general, HMIH fared better than FIH in all cases studied,except for a few instances (pr439, eil51, and eil101) where FIH either performed equally or slightly better thanHMIH. HMIH’s efficiency is shown by its improvements in error percentage (δ) and goodness values (g) comparedto FIH and NNH. In the att48 instance, HMIH had an error rate of 6.3%, whereas FIH had 14.6% and NNH had20.9%, indicating that HMIH was closer to the optimal solution. HMIH consistently showed superior performanceacross many benchmarks,

关键词： Nearest neighbour heuristic farthest insertion heuristic half max insertion heuristic tour construction travelling salesman problem

Effect of functional composite coating developed via sulphate and chloride process parameter on the UNS G10150 steel for structural and wear mitigation in defence application

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Defence Technology（防务技术） 2018年第3期14卷 196-203页

作者： Ojo sunday Isaac Fayomi Department of Mechanical Engineering Covenant University Department of Chemical Metallurgical and Materials Engineering Tshwane University of Technology

The major engineering challenge of materials in defence technologies is the vulnerability of based metals to structural and wears deformation in service. In this paper, structural formation, mechanical and thermal stability behavior of developed composite coating of Zn-30 Al-7%Ti/Sn chloride bath and Zn-30 Al-7%Ti/Sn sulphate bath was investigated and compared to provide mitigation against failure. The thermal ageing property was done for 2 h at 600C via isothermal furnace. The structural, interfacial effect and stability behaviors of the co-deposited alloys were evaluated using scanning electron microscope equipped with energy dispersive spectrometer(SEM/EDS), atomic force microscope(AFM) and Xray diffractometer(XRD). The hardness and wear properties of the deposited coatings were examined with diamond base micro-hardness tester and reciprocating sliding tester respectively. The result shows that Zn-30 Al-7%Ti/Sn sulphate co-deposition contributed to increase hardness and wear resistance than Zn-30 Al-7%Ti/Sn chloride bath alloy. The stable crystal growth and significant performance of Zn-30 Al-7%Ti/Sn sulphate are link to the intermetallic phase hybrid of Zn Al, Zn4 Ti Al2, Zn3 Al Ti. Besides, it was observed that Zn-30 Al-7%Ti/Sn sulphate has excellent thermomechanical stability at harsh temperature,due to the deposition of Sn/Ti on steel; leading to formation of super-hard interface. However, it was established that co-deposition of mild steel with Zn-30 Al-7%Ti/Sn in sulphate bath significantly improved the structural and wear performance. It was shown that the hardness and wear of the developed composite Zn-30 Al-7%Ti/Sn is increased by about 80% compared to as received sample and about 25% compared with Zn-30 Al-7%Ti/Sn chloride coating developed. The improvement was proved to be an interference of zinc-composite growth. Thus, this work shows that sulphate induced Zn-30 Al-7%Ti/Sn via generation of controllable process parameter can provide significant improv

关键词：防卫技术硫酸盐氯化物低碳钢结构涂层合成 UNS

A compositional function hybridization of PSO and GWO for solving well placement optimisation problem

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Petroleum Research 2022年第3期7卷 401-408页

作者： Daniel Ocran sunday sunday Ikiensikimama Eric Broni-Bediako University of Mines and Technology(UMaT) Department of Petroleum and Natural Gas EngineeringTarkwaGhana Universty of Port Harcourt Department of Petroleum and Natural Gas EngineeringPort HarcourtNigeria

Advances in technology and optimisation are helping to improve decision making in the oil and gas ***,most of the traditional metaheuristic algorithms applied in well placement optimisation problems suffer from extensive parameter experimentations and local optimum trapping *** couples with the complex and heterogeneous nature of hydrocarbon reservoirs and increased decision variables poses severe simulation process *** study considered a functional composition integration approach to formulate a robust hybrid metaheuristic algorithm called *** HGWO-PSO leverages on the strengths of Grey Wolf Optimiser(GWO)and Particle Swarm Optimisation(PSO)and the Clerc's parameter setting considerations.A rigorous approach which enforces regulatory agreed minimum well spacing was incorporated in the optimisation *** models ranging from unimodal to multimodal spatial systems were used as examples to test the explorative and exploitative capabilities of the *** this paper we show the performance curve and statistical analysis of HGWO-PSO as a well placement algorithm and compares its performance with that of standalone PSO,and GWO and the traditional Genetic Algorithm(GA).Results revealed that the HGWO-PSO demonstrated comparative performances in terms of exploration and exploitation obtaining the best optimal solutions which give highest contractor's NPVs in majority of cases ***,the means and standard deviations for HGWO-PSO among the various runs showed consistent and efficient *** Wilcoxon signed rank test conducted gave very low p-values suggesting uniqueness of HGWO-PSO from the other metaheuristic ***,the computational speed of HGWO-PSO was relatively better as compared to the individual GWO and PSO in most the test *** simulation results for all test cases confirm that implementation of HGWO-PSO can cause considerable improvement in locations of wells even in hete

关键词： Well location optimisation Metaheuristic algorithms Oilfield development Hybridisation

Placental Malaria and Pre-Eclampsia from the Lagos State University Teaching Hospital, Ikeja, Lagos Nigeria

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International Journal of Clinical Medicine 2019年第11期10卷 613-621页

作者： Abidoye Gbadegesin sunday Soyemi Joy Agbara adekunle Sobande Samuel Adebayo Department of Obstetrics & Gynaecology Ikeja Lagos Nigeria Lagos State University Teaching Hospital Ikeja Lagos Nigeria Department of Pathology and Forensic Medicine College of Medicine Lagos State University Ikeja Lagos Nigeria

Objective: To determine the relationship between placental malaria infection and pre-eclampsia in a holo-endemic zone. Design: Prospective case-control study. Materials and Methods: One hundred and twenty seven (127) pregnant women with a diagnosis of pre-eclampsia in labour or having caesarean section served as cases while controls were 127 normotensive parturient women. They were recruited from the maternity unit of Ifako Ijaiye and Isolo General Hospitals, Lagos that served as secondary care centers. At delivery, either spontaneous vaginal delivery or by caesarean section, a 2.0 cm × 2.0 cm placenta tissue was cut with scalpel and fixed in 10% formaldehyde in a specimen bottle and sent to the pathologist. Following this, 2.5 mls of Cord blood and 2.5 mls of the maternal venous blood were taken into separate EDTA bottles properly labeled at delivery, samples were sent to the haematology laboratory immediately for peripheral thick film smear for malaria parasite. Results were obtained from the laboratory and together with data from the case files, they were entered into SPSS version 16 for analysis. Independent Student t-test was used for significance for continuous variables while Chi-square was used for qualitative data. The significance was set at 0.05. Results: There were statistically significant differences between the cases and controls regarding the maternal age, number of pregnancies, p p > 0.05. There was statistically significant difference between the two groups regarding the diagnosis of placental malaria as well as past history of alcohol intake and occupation, p Conclusion: Placental malaria infection was more common in patients with preeclampsia than their matched normotensive patients in our environment. At the same time, chronic malaria was found to be an independent risk factor for preeclampsia. More concerted efforts by all stake holders should be geared towards primary prevention together with early diagnosis and treatment of malaria especially

关键词： Placental Malaria Preeclampsia Holoendemic Zone

Numerical modeling and parametric sensitivity analysis of heat transfer and two-phase oil and water flow characteristics in horizontal and inclined flowlines using OpenFOAM

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Petroleum Science 2023年第2期20卷 1183-1199页

作者： Nsidibe sunday Abdelhakim Settar Khaled Chetehouna Nicolas Gascoin INSA Centre Val de Loire UniversitéOrléansPRISME EA 4229F-18020BourgesFrance

Estimating the oil-water temperatures in flowlines is challenging especially in deepwater and ultra-deepwater offshore applications where issues of flow assurance and dramatic heat transfer are likely to occur due to the temperature difference between the fluids and the surroundings. Heat transfer analysis is very important for the prediction and prevention of deposits in oil and water flowlines, which could impede the flow and give rise to huge financial losses. Therefore, a 3D mathematical model of oil-water Newtonian flow under non-isothermal conditions is established to explore the complex mechanisms of the two-phase oil-water transportation and heat transfer in different flowline inclinations. In this work, a non-isothermal two-phase flow model is first modified and then implemented in the InterFoam solver by introducing the energy equation using OpenFOAM® code. The Low Reynolds Number (LRN) k-ε turbulence model is utilized to resolve the turbulence phenomena within the oil and water mixtures. The flow patterns and the local heat transfer coefficients (HTC) for two-phase oil-water flow at different flowlines inclinations (0°, +4°, +7°) are validated by the experimental literature results and the relative errors are also compared. Global sensitivity analysis is then conducted to determine the effect of the different parameters on the performance of the produced two-phase hydrocarbon systems for effective subsea fluid transportation. Thereafter, HTC and flow patterns for oil-water flows at downward inclinations of 4°, and 7° can be predicted by the models. The velocity distribution, pressure gradient, liquid holdup, and temperature variation at the flowline cross-sections are simulated and analyzed in detail. Consequently, the numerical model can be generally applied to compute the global properties of the fluid and other operating parameters that are beneficial in the management of two-phase oil-water transportation.

关键词： Flow assurance Flow pattern Heat transfer Flowlines Two-phase flow Global sensitivity analysis

Anti-Corrosion and Tribo-Mechanical Properties of Co-deposited Zn–SnO_2 Composite Coating

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Acta Metallurgica Sinica(English Letters) 2015年第4期28卷 521-530页

作者： Ojo sunday Isaac Fayomi Abimbola Patricia Idowu Popoola Department of Chemical Metallurgical and Materials EngineeringTshwane University of Technology Department of Mechanical Engineering Covenant University

Zn-SnO2 composite coatings were prepared by direct potential using electrolytic co-deposition technique from sulfate solution. The effect of Zn2＋ and SnO2 concentrations in deposited bath on the mechanical properties and mor- phological characteristics of the composite coatings were examined. The characterizations of the sample were analyzed using scanning electron microscopy couple with energy dispersive spectroscopy （SEM/EDS）, X-ray diffraction （XRD） and atomic force microscopy （AFM）. The electrochemical degradation behavior of the samples in 3.65 wt.% NaCl solution was studied using potentiodynamic polarization technique and characterized by high-resolution optical microscope. From all the fabricated composite coatings, obvious diffraction peaks were observed with Zn-7Sn-S-0.3V film with Zn2Sn7, Sn, Zn2Sn5 and Zn phases, confirming the presence and formation of Zn-SnO2 coating. The XRD pattern shows that the presences of SnO2 particle remarkably play a major role in the precipitation and orientation of the alloy matrix. From the SEM/EDS and AFM results, the deposits show that composite particle and proper bath composition have strong influence on the microstructure. An enhanced corrosion resistance was attained as a result of the induced particles.

关键词： Metal matrix composite Co-deposition Mechanical property Corrosion resistance

Inclusion engineering and metallurgy of calcium treatment

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Journal of Iron and Steel Research International 2018年第2期25卷 133-145页

作者： sunday Abraham Rick Bodnar Justin Raines Yufeng Wang SSAB Americas Muscatine IA 52761 USA

Although a great deal of research has been done in the area of inclusion control during steelmaking, a complete description of the process of inclusion modification and shape control cannot be found in literatures. As a result, the terms ＂inclusion modification＂ and ＂shape control＂ are often used loosely in the technical community. To utilize the full potential offered by a calcium treatment, it is important to understand why an inclusion whose composition has been modified may not necessarily have its shape modified. With the purpose of decoupling the process of inclusion phase change from inclusion shape control, and to provide a complete description of the metallurgy of calcium treatment, a detailed literature survey has been performed on the subject. By coupling the survey with a new concept developed to tailor the cleanliness of steels to the intended applications, the hope is to provide the reader with valuable information on calcium treatment for inclusion modification and shape control.

关键词： Nonmetallic inclusion Cleanliness Calcium treatment Inclusion modification Inclusion shape control

Diagenetic and Reservoir Quality Variation of Miocene Sandstone Reservoir Analogues from Three Basins of Southern California,USA

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Journal of Earth Science 2020年第5期31卷 930-949页

作者： sunday E.Okunuwadje David MacDonald Stephen Bowden School of Geosciences University of AberdeenAberdeen AB243UEUK Department of Geology University of BeninBenin City PMB 1154Nigeria

The Miocene sandstone deposits in the Southern California region are important hydrocarbon reservoirs. However, their development has been very challenging due to the wide variability in their reservoir quality. These sandstones have been studied from three sedimentary basins by petrographic thin section, scanning electron microscope, and X-ray diffraction to evaluate and compare the influence of diagenesis on their reservoir quality in these basins. Four petrofacies, namely P1(sand injectite or dyke), P2(sub-marine fan), P3(turbidite and marine-influenced alluvial fans) and P4(continental sandstones) have been identified. P1 and P2 characterise the sandstones in the San Joaquin forearc basin and are affected by kaolinite and extensive early calcite diagenesis. P3 and P4 delineate the sandstones in the Cajon Valley and Salton Trough strike-slip basins and are dominated by smectite, mixed illite-smectite, early calcite and late calcite diagenesis. Early calcite cement in P3 and P4 is in lower proportion than in P1 and P2. Although the dissolution of these sandstones by acidic fluids did not have a pattern, it, however, has the most considerable influence on P2 creating moldic pores which are expected to increase pore connectivity. The relatively abundant dissolution pores in P2, together with the absence of late authigenic calcite and illite clay in comparison to the other petrofacies studied are likely to make this sandstone facies the best reservoir targets in the Southern California region. These rocks are analogous to producing reservoirs in the region. However, because, petroleum accumulation in these reservoirs are compartmentalized by early calcite cement, maximum recovery using acidified fluids is recommended to dissolve the calcite-filled pores in order to increase connectivity of their pore network and enhance flow potential.

关键词： diagenesis petrofacies reservoir quality Miocene California