Browsing by Author "Adebayo, A. S."

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Annotation of virulence factors in schistosomes for the development of a SchistoVir database
(Academic Journals, 2013-04) Adebayo, A. S.; Anumudu, C. I.
Scientific efforts in the eradication of neglected tropical diseases, such as those caused by the parasitic helminthes, can be improved if a database of key virulence factors directly implicated in pathogenesis is available. As a first step towards creating SchistoVir, a database of virulence protein factors in schistosomes, in this study, we curated, annotated and aligned sequences of twenty virulence factors identified from the literature, using several bioinformatics tools including UniProtKB, SchistoDB, VirulentPred, InterProScan, ProtScale, MotifScan, TDRtarget, SignalP, MODBASE, PDB and MUSCLE. Among the protein entries, the most frequently occurring amino acid residues were lysine, serine, leucine, glutamine, glycine and cysteine in order of magnitude. Although sequence repeat regions (SRRs) of significant value were identified manually in fifty percent of the proteins (while dipeptide repeats (DiPs) and single amino acid repeats (SAARs) were not), nevertheless, seventy-two percent of the protein entries were classified as virulent by the prediction model, VirulentPred. Most of the entries (eighty percent) did not have target compounds based on the database of available chemical compounds at TDRtargets. Fourteen of the twenty entries (seventy percent) had more than 30 consecutively negative amino acid residues based on the ProtScale’s Kyte and Doolittle hydrophobicity plot. Hence, they would be hydrophobic enough to be transmembrane in location or secretory in nature. Only 7 (tyrosinase, serine protease1, Tspan-1, VAL4, cathepsin b and L and calreticulin) had cleavage sites and signal peptides, while none had a significant signal anchor probability. The annotations and characterization provided by this work and the development of a SchistoVir database will aid in further research of schistosome pathogenesis and control.
Control modelling of coupled shell and tube heat exchangers using combined neural network and fuzzy logic
(2022) Petinrin, M. O.; Oke, O. S.; Adebayo, A. S.; Towoju, O. A.; Ismail, O. S.
Control of the temperature of the outlet fluid in heat exchanger network is very important to maintain safety of equipment and meet the optimal process requirement. Conventional PID controllers have the limitations of meeting up with wide range of precision temperature control requirements, and then the predictive controllers have recently emerged as promising alternatives for advanced process control in heat exchanger systems and other industrial applications. This paper focuses on the control of output temperature of coupled shell and tube heat exchanger by combining fuzzy logic and Neural Network control system. To achieve effective control, transfer functions from the energy balance equations of the heat exchanger unit and other components were obtained. Simulation of the control process was carried out using Simulink interface of MATLAB. The time response analysis in comparison with variants of conventional PID controllers shows that combination of Neural Network and fuzzy logic controllers can efficiently improve the performance of the shell and tube heat exchanger system while in with 0.505% overshoot and less settling time of 12.74 s, and in parallel with the same overshoot of 0.505% and settling time of 11.37 s. The demonstration of the lower error indices of the neuro-fuzzy controlled system also indicated its better performance.
Development of repaglinide microspheres using novel acetylatedstarches of bitter and Chinese yams as polymers
(Elsevier B.V., 2016) Okunlola, A.; Adebayo, A. S.; Adeyeye, M. C.
Tropical starches from Dioscorea dumetorum (bitter) and Dioscorea oppositifolia (Chinese) yams were acetylated with acetic anhydride in pyridine medium and utilized as polymers for the delivery of repaglinide in microsphere formulations in comparison to ethyl cellulose. Acetylated starches of bitter and Chinese yams with degrees of substitution of 2.56 and 2.70 respectively were obtained. Acetylation was confirmed by FTIR, 1 H NMR spectroscopy. A 32 factorial experimental design was performed using polymer type and drug-polymer ratio as independent variables. Particle size, swelling, entrapment and time for 50% drug release (t50) were dependent variables. Contour plots showed the relationship between the independent factors and the response variables. All variables except swelling increased with drug: polymer ratio. Entrapment efficiency was generally in the rank of Bitter yam > Ethyl cellulose > Chinese yam. Repaglinide microspheres had size 50 ± 4.00 to 350 ± 18.10μm, entrapment efficiency 75.30 ± 3.03 to 93.10 ± 2.75% and t50 3.20 ± 0.42 to 7.20 ± 0.55h. Bitter yam starch gave longer dissolution times than Chinese yam starch at all drug-polymer ratios. Drug release fitted Korsmeyer-Peppas and Hopfenberg models. Acety-lated bitter and Chinese yam starches were found suitable as polymers to prolong release of repaglinidein microsphere formulations.
Evaluation of palm kernel oil as cutting lubricant in turning AISI 1039 steel using taguchi-grey relational analysis optimization technique
(Elsevier, 2023) Alaba, E. S.; Kazeem, R. A.; Adebayo, A. S.; Petinrin, M. O.; Ikumapayi, O. M.; Jen, T. C.; Akinlabi, E. T.
Cutting fluids have a known negative impact on productivity, human health, and the environment in the manufacturing sector. A suitable method for reducing the effect of cutting fluids on human health and the environment is minimum quantity lubrication (MQL). In this experiment, AISI 1039 steel was machined using vegetable oil lubricant and MQL. A chemical method was used to extract vegetable oil from palm kernel seeds. Then, using established techniques, the physicochemical and lubricity properties of palm kernel oil (PKO) were ascertained. The Taguchi L9 (33) orthogonal array served as the basis for the planning of the experimental design. Process parameters such as surface roughness, chip thickness ratio, cutting temperature, and material removal rate were measured during the turning operations. The multi-response outputs from TGRA were considered to simultaneously optimize the cutting parameters namely depth of cut, feed rate, and spindle speed. At a temperature of 55◦C, 180 min, and particle sizes of 0.2–0.5 mm, an oil yield of 55% by weight was obtained. The viscosity at 40◦C, specific gravity, pour, fire, cloud, and flash points of the raw PKO were 117.6 mm2/s, 0.8940 mg/ml, 21◦C, 231◦C, 22.3 ◦C and 227◦C, respectively. The surface roughness and cutting temperature of PKO improved by 44% and 12%, respectively, when compared with mineral oil. The findings of this research confirmed the effectiveness of the integrated Taguchi-grey relational analysis (TGRA) optimization method and established an experimental foundation for the use of PKO minimum quantity lubrication turning.
Experimental study of flow and heat transfer in rectangular ducts with ribbed surfaces
(2022) Petinrin, M. O.; Ajuka, L. O.; Adebayo, A. S.; Oderinlo, O. U.
The Pivotal focus on fluid and thermal equipment performance have remained to directly lower energy cost by utilizing varieties of surface structures including extended surfaces, treated surfaces, and rough surfaces. This has necessitated the resurgence of surfaces with dimples and protrusions for an enhanced system efficiency in electronic components, gas turbine blade cooling, vortex creation on air foil structures, combustion chambers, printed circuit boards, microfluidic passageways, and heat exchangers features. In this study, the performance characteristics, heat transfer enhancement (Nu/Nuo), friction factor ratio (f/fo), and overall thermal performance (OTP) of two test channels with distinct surface structures. The performance parameters were evaluated using experimental rigs, one with continuous spiral rib channel and the other one with discontinuous spiral rib channel. Thereafter, the results from both test channels were compared to a smooth surface channel. Comparing the performance characteristics, Nu/Nuo, f/fo, and OTP of the discontinuous spiral rib and continuous spiral rib were 31.5%, 91.3%, 4.4% and 81.9%, 113.6%, 38.4% higher than the smooth surface spiral rib channel. Finally, the study shows that the continuous spiral rib channel gave a lower pressure loss, and was established to possess higher heat transfer coefficient and overall thermal performance than the discontinuous spiral rib channel.
Genetic characterization of fin fish species from the Warri River at Ubeji, Niger Delta, Nigeria
(Academic Journals, 2014-07) Asagbra, M. C.; Adebayo, A. S.; Ugwumba, O. A.; Ugwumba, A. A. A.; Anumudu, C. I.
A study to evaluate the genetic similarities and differences among 11 specimens of cichlids and four specimens of mudcatfishes obtained from Warri River was carried out through DNA fingerprinting analysis using random amplified polymorphic DNA (RAPD) amplification with seven decamer primers and dendrograms through unweighted pair-group method with average (UPGMA) cluster analysis. The total number of bands generated by seven RAPD primers, ranged between 2 to 33 for the cichlids and 8 to 28 for catfish family, with band size between 100 to 800 bp. The primers produced 228 bands in total 119 for cichlids and 109 for the catfishes, with 24% polymorphism. Considerable genetic variation was observed within species (especially within Tilapia Zilli, T. guineesis and Clarias gariepinus), between species in same genera (T. zilli and T. guineensis ) and among cichlids and catfishes. The most consistent of the RAPD primers generated 87 bands among the cichlids with 23 bands (26%) polymorphic and 74% conserved. Among the catfishes, the primers produced 69 bands with 16 (23%) polymorphic. The data show that the RAPD technique was useful and sensitive in differentiating various fish genera and species.
Polycyclic aromatic hydrocarbons in water, sediment and fish from the Warri River at Ubeji, Niger Delta, Nigeria
(NISC (Pty) Limited and Taylor & Francis, 2015) Asagbra, M. C.; Adebayo, A. S.; Anumudu, C. I.; Ugwumba, O. A.; Ugwumba, A. A. A.
The Warri River at Ubeji, Nigeria, receives pollutants from an oil refinery. The levels of 16 priority polycyclic aromatic hydrocarbons (PAHs) in water, sediment and the tissue of tilapia from the Warri River were investigated in 2010 using gas chromatography with mass spectrometry. Eleven PAHs were found in the sediment and nine in fish and water, with total mean concentrations of 4 587.7 ng g-1, 1 098.5 ng g-1 and 34 ng ml-1 in sediment, fish tissues and water, respectively. Lower molecular weight PAHs were predominant, with naphthalene accounting for the highest concentration in all samples. Carcinogenic PAHs detected included benzo(a)pyrene, benzo(a)anthracene and chrysene. The predominance of lower molecular weight PAHs in the study area is an indication of recent pollution of petrogenic origin from the Warri Refining and Petrochemical Company’s refinery.