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Item Open Access Molecular characterization of methicillin resistant staphylococcus aureus from clinical specimens and antimicrobial activity of plant extracts against the isolates(Federal University of Technology, Owerri, 2021-09) Ifediora, Afoma ChinweStaphylococcus aureus is a major bacterial pathogen that causes different community and hospital-acquired infections. S. aureus resistant to methicillin has become a big and expanding problem of concern in many developing countries. This study examined the molecular characterization and the effect of plant extracts on methicillin resistant Staphylococcus aureus (MRSA) from clinical specimens in Abia State, Nigeria using standard recommended procedures. Conventional cultural, morphological and biochemical methods were used to identify the isolates, while the antimicrobial susceptibility testing was performed by the disc diffusion method. Methicillin resistance was detected phenotypically using cefoxitin 30µg disc and oxacillin 1µg disc. Inducible clindamycin resistance was evaluated by the D-test. Polymerase chain reaction (PCR) was used to amplify genes for methicillin resistance (mecA), clindamycin resistance (ermB), beta-lactamase production (blaZ), Panton Valentine leukocidin (pvl) with 16SrRNA gene being the internal control. Sequencing was carried out on the amplified isolates. The Random Amplified Polymorphic DNA (RAPD) was implemented on the mecA strains isolated using three randomly selected oligonucleotide primers. Plant antimicrobial assay was done using the agar well technique and phytochemicals detected in the two plants tested. A total of 750 clinical specimens of blood, urine samples, wound, ear, nasal, high vaginal, urethral and ear swabs were collected from three major health facilities located in the three senatorial zones of Abia State, Nigeria. A total of 265 (35.3%) S. aureus isolates were recovered, out of which 126(47.5%) were from males and 139(52.5%) were from females, however there was no association between the prevalence and gender (p-value = 0.05) and also prevalence and age (p-value = 0.52). Phenotypic detection of MRSA using cefoxitin disc diffusion gave an MRSA prevalence of 164(61.9%) with 65(39.6%) being from urine, 3(23.1%) from wound, 31(18.9%) from high vaginal swab, 22(13.4%) from urethral swab, 4(2.4%) from ear swab, 3(1.8%) from nasal swab and 1(0.6%) from blood samples. All (100%) of the MRSA were susceptible to vancomycin, 120(73.2%) to clindamycin, 92 (56.1%) to gentamycin. All were resistant to ceftazidine, 157(95.7%) to cloxacillin, 146(89.0%) to augmentin, 136(82.9%) to ceftriaxone and 103(61.6%) to erythromycin. The MRSA strains showed much higher resistance rate than their methicillin susceptible Staphylococcus aureus (MSSA) counterparts to all tested antibiotic except clindamycin. Exactly 64(39.0%) of the MRSA were resistant to 4 classes of antibiotics indicating multi drug resistance (MDR). The overall prevalence of inducible clindamycin resistance among methicillin resistant isolates was 29(17.7%) while 66.5% xix produced beta-lactamase. Out of 40 cefoxitin positive isolates, 12 (30%) possessed mecA gene, 17.5% harboured the β-lactamase (blaZ) gene, 20% and 10% possessed the pvl gene. Dendogram analysis of RAPD-PCR amplification of mecA positive strains showed three different clones in circulation in the state. The plant extracts showed varied levels of antimicrobial activity against the MRSA isolates. The growth of the microorganisms used for the test was inhibited by the ethanolic extracts of the leaves of Alchornea cordifolia and Acalypha wilkesiana at concentrations of 50mg/ml to 200mg/ml. The inhibition zones ranged from 9.0mm to 21.0mm whereas the water extracts showed moderate activity against the isolates. The Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) of Alchornea cordifolia ranged from 12.5-50mg/ml and 25-100mg/ml for Acalypha wilkesiana. The results of the rates of kill revealed a gradual reduction in the total viable count of bacteria from 1hr to 24hrs in all the test isolates. The phytochemical screening of the ethanol extract revealed the presence of tannins, flavonoids, glycosides, resins and carbohydrates but in variable degrees. The percentage yields of phytochemical content of the leaves of the Alchornea cordifolia plants were as follows: alkaloids (1.85%), flavonoids (1.08%), Glycosides (1.05%), saponins (4.13%), and tannins (0.70%). The use of phenotypic and molecular methods in this study provided useful information on antibiotic resistance and genetic diversity of S. aureus isolates from clinical specimens in Abia State of Nigeria. The information provided could help in monitoring the evolution of S. aureus strains in Nigeria over time.Item Open Access Analysis of gender equality opportunities and resource use in cereal value chain: Evidence from youth engagement in rice value chain in Sourth-East, Nigeria.(Federal University of Technology,Owerri, 2023-09) Tim-Ashama, A. C.The study analyzed gender equity opportunities and resource use in cereal value chain: evidence from youth engagement in rice value chains in Nigeria. it identify the actors and gender roles along rice value chain; examine by gender, the socioeconomic characteristics of actors along the rice value chain; determine the level of gender equity gap in opportunities along the rice value chain; determine the technical efficiency and sources of inefficiency among male and female actors along the rice value chain; determine the value added and the share of the value added by gender along the rice value chain; estimate the factors affecting value added by gender along rice value chain and, identify the constraints to youth engagement in the rice value chain, by gender. A multistage sampling technique was adopted for this study. The sample size consists of 476 youth rice value chain actors randomly selected from 48 villages across three states in South-East Nigeria. The data were collected using questionnaires and analyzed using Modified Gender Equity Index (MGEI), stochastic meta-frontier, value addition and multiple regression models. Descriptive statistics such as frequency, percentages, charts and mean were also used to realize some additional results. Results from MGEI show that the level of gender equity opportunities for youth rice producers, processors and marketers were-0.21,-0.21 and-0.04, respectively, indicating inequity against the female youth. The mean technical efficiency for male and female producers are 0.64 and 0.59, processors 0.70 and 0.69 and marketers 0.52 and 0.61. The determinant factors of technical inefficiency among male and female youth in the study area were level of education, membership of cooperative society, years of experience and access to credit. The overall value-added per tonne by the male youth actors was ₦52,281 and the female youth actor was ₦52,229. The share of the value-added by male youth producers, processors and marketers were 51.65%, 49.41% and 47.78% while the female youth were 48.38%, 50.59% and 52.22%, respectively. Some factors affecting value added by actors in rice value chain were level of education, years of experience, capital invested, information and distance to actor’s node. The major constraints to youth engagement in rice value chain include lack of capital to start up, lack of access to credit, drought, lack of access to better technology, high cost of hiring/operating machines, lack of technical knowhow/skills, and stressful nature of rice value chain. In addition, the female processors added marital challenges and responsibilities as a major challenge while recommends that Policies and interventions that ensure equal access to resources, opportunities, and decision-making power for both male and female youth actors should be implemented through targeted training programmes, awareness campaigns and capacity-building initiatives that promote gender equality. In addition, access to affordable credit and financial services for youth involved in rice value chain should be strengthened through establishment of financial institutions and mechanisms specially targeting youth in agricultural sectors.Item Open Access Ecological risk assessment and phytoremediation of spent engine oil contaminated soils of selected mechanic workshops in Imo State(Federal University of Technology, Owerri, 2023-05) Azorji, Johnpaul NnawuikeAssessment of the ecotoxicological risk of indiscriminate disposal of spent engine oil on terrestrial ecosystem was investigated using physicochemical, biochemical, and bioterance assays. Soil samples were collected from a depth of 0-20cm and analyzed using standard analytical protocols. Acute toxicity tests were conducted based on germination and seedling establishment of higher plants (Zea mays, G. maxV. unguiculata), Earthworms (mortality rate) and microorganisms (inhibitory effects) which covered a wide range of short-term lethal and sub-lethal endpoints used for risk characterization and analyzed using Probit analysis. Results obtained showed that majority of the mechanics who are within 20-30 age bracket were found in Owerri (22.42%) while the least was found in Okigwe (12.98%); on weekly basis, 42 vehicles are serviced in Owerri; 27 inOrlu while 21 is been serviced in Okigwe respectively. Total annual volume of spent engine oil generated (in litres) was highest in Owerri zone (124,489.36L) while the least value was obtained in Orlu zone (18,434.52L). A significant volume 168 (49.56%) of the spent engine oil is been disposed into the immediate environment with others being sold off 41 (12.09%); given out for free 66 (19.47%); and taken by car owners 64 (18.88%). Axonopuss compressus, Aspillia africana, and Chromolaena odorata species were the dominant plant species identified in the order: Axonopuss compressus>Aspillia africana> Chromolaena odorata. Mean values of physical and chemical properties of soil indicated alteration of parameters analyzed relative to the control. The mean concentrations of heavy metals across the zones ranged from Pb(1.045 ± 0.1 to 1.534 ± 0.2), As (1.761 ± 0.3 to 1.805 ± 0.3), Cr (0.272 ± 0.01 to 0.273 ± 0.01), Cd (0.302 ± 0.02 to 0.606 ± 0.03), Ni (0.918 ± 0.03 to 0.932 ± 0.03), Co (1.278 ± 0.1 to 1.324 ± 0.2), Fe (63.927 ± 3.34 to 69.563 ± 3.53), Cu (12.446 ± 2.14 to 12.964 ± 2.42), Zn (156.121 ± 28.01 to 156.137 ± 28.12), and Al (1.353 ± 0.2 to 1.353 ± 0.12) mg/kg with a distribution pattern of Zn>Fe>Cu>As>Al>Co>Pb>Ni>Cd>Cr. Concentration of heavy metals were significantly (p<0.05) higher at the polluted sites than the control and above WHO permissible limits. Mean concentration of PAHs ranged between Owerri zone (0.03 ± 0.01 to 1.980 ± 0.36mg/kg) Orlu zone (0.004 ± 0.001 to 1.614 ± 0.10 mg/kg), and in Okigwe zone (0.01 ±0.001 to 1.418 ± 0.19mg/kg) with distribution pattern of Nap>Pyr>Mepl>Ind>Acpt>Flu>Bbf>B(ghi)p>B(g)p>Bkf>Da>An>Acph across the zones.Maximum Concentration of TPH was recorded in Owerriwhile the minimum value was gotten from the control site. Mean values of TPH were in the order: Owerri>Orlu>Okigwe>control. Result of acute toxicity assay showed that Zea mays exhibited more sensitivity than V. unguiculata and G. max. The microbial absorbance rate depended on the dose and type of organism in the order of: Acinetobacter>Enterobacter> Bacillus species >Pseudomonas. Mortality in earthworm was noted as concentration increased. Values of Risk Quotient for Zea mays, V. unguiculata, G. max and earthworm ranged from low risk to very high risk based on the estimated PNEC values. The microorganisms differed slightly in biotolerance to spent engine oil exposure based on estimated risk quotients. Exposure to spent engine oil posed minimal risk to Pseudomonas sp., Bacillus sp., and Acinetobacter sp., at the estimated PNECs with values less than unity (<1). Risk quotient values for Enterobacter sp. indicated a high risk with values above unity. Variable xxi concentrations of heavy metals were accumulated by the plants from soil and were stored in the root, shoot and leaf except for A. compressus that accumulated values less than one (<1) for Pb and As. Metal accumulation pattern were in the order C. odorat>A.africana>A.compressus. C. odorata and A. africana exhibited characteristics typical of a phytoextractor while A. compressus could be applied as a phytostabiliser of spent engine oil polluted soils. The sensitivities exhibited by the organisms exposed to spent engine oil indicate the possibility of using them as bioindicators and for assessing the efficacy of phytoremediation process. Spent engine oil adversely affected the organisms in each scenario in a dose dependent manner. Overall, these findings proved that spent engine oil greatly altered soil properties and also repressed the growth of organisms in the ecosystem thereby strengthening the need to curb indiscriminate disposal of spent oil on the environment by mechanics in the business of auto repairs to forestall possible pollution problems of other components of the food chain.Item Open Access Design and modelling of smart home technologies for the aged persons(Federal University of Technology, Owerri, 2021-07) Okoroafor, Godfrey NwajiSmart home technology for the aged persons here is a wireless sensor-based home system that provide the aged persons a safe, sound and secure home environment, while enabling them to live independently in their own homes as long as possible. The aged persons here are that population within the ages of 65 years and above. Nowadays, the rapid increase in the number of aged persons, including those with disabilities, the decrease in the number of family care-givers as a result of youths` migration to cities in search of white-collar jobs, and inability of government to provide adequate infrastructural needs to these aged persons has resulted in a miss-match on the caring facilities in Nigeria. These have contributed to the problem of these aged persons, since neither families nor government are able to meet their needs, especially in Africa due to high level of mass poverty, illiteracy and corruption in governance. Therefore, the task of this proposed system here is to design and model a voice activated home control system that will utilize the natural voice of the aged home occupants, to provide a more convenient, easier to install and use, user friendly home technologies for the aged persons. This will enable them maneuver assistive wheelchair, and manage home appliances through voice commands. This assistive wheelchair developed is embedded with collision detection and avoidance. The tools used to realize this proposed system are; The Personal Computer (PC), HC-SR04 ultrasonic sensor, and Voice Recognition (VR) module in a PC used for voice processing and recognition, Microphone for voice signal acquisition, C-language with the help of C# for coding. Bluetooth and Radio Frequency (RF) transceivers wirelessly link the input module to the controller module (microcontroller) which selects the appliances/assistive device to be controlled according to the input voice command. Proteus Virtual System Modelling (VSM) was used for developing smart home technology system schematic model and carried out the animated simulation to validate the system`s performance within the home. The designed system was tested on Dead Home (a home with closed curtains, carpet, an air-conditioner, and other leaving home appliances switched off) and Live Home (a home with opened curtains, carpet, an air-conditioner, television, and other leaving home appliances, switched on, and with background music or noise from a stereo people) conditions, and the effective result was 92.93% for dead home and 75.85% for live home respectively. This showed that the realized system controlled the devices with voice, though, the level of this system response is higher in dead home than in a live home, hence, the level of the system performance is lower in a noisy environment.Item Open Access Biochemical and carcinogenic effects of monosodium glutate and soya bean in wistar rats(Federal University of Technology, Owerri, 2021-07) Bob Chile-Agada, AdaezeThis study was carried out to investigate the biochemical effects of short, medium and long term administration of monosodium glutamate (MSG) and soya beans in both male and female Wistar rats, using standard methods. LD50 was carried out using rats which led to the choice of 1000, 2000 and 3000 mg/kg b.w for low, medium, and high doses of the samples. A total of 210 (105 males and 105 females) weanly Wistar rats weighing 70 – 78g were divided equally into three groups of 70 rats each representing the various experimental durations (2, 4, and 6 months). Each of these groups containing 70 rats was further divided equally into 14 subgroups, each containing 5 rats. Group 1 and 8 were controls for female and male rats fed normal raw chow and saline. Groups 2-7 (female rats) and 9-14 (male rats) were rats administered low dose (LD), medium dose (MD) and high dose (HD) MSG and soya beans respectively. 6-o-Malonylgenistin (98.47%) and Glycitin (98.11%) were the most abundant oestrogen-like compounds in the dehulled and oil of soya beans. The glucose and insulin levels of both male and female rats were significantly altered by HDs of both MSG and soya beans after 6 months while ALT, ALP and AST levels were significantly elevated after 4 and 6 months following administration of both MSG and soya beans and were more extensive in HD soya bean fed rats. No significant changes (P> 0.05) were observed in the urea levels after 2 and 4 months soya beans respective administration to female and male rats, while HD MSG significantly elevated the creatinine levels of male and female rats after 4 and 6 months administration. Administration of soya beans and MSG for 2 and 4 months had no significant effect (P > 0.05) on the bicarbonate and chloride levels. The HDL levels were significantly reduced while LDL, TC, and TG were significantly (P < 0.05) elevated after 6months HD administration of MSG and soya beans. Soya beans administration produced no significant change in the SOD levels for female rats and catalase levels in male rats after 2 months administration whereas the MD and HD administration of MSG significantly elevated MDA levels of both male and female rats after 4 and 6 months. Two and four months administration of soya beans and MSG produced no significant changes (P > 0.05) in the LH and FSH of female rats while MD and HD of MSG and soyabean significantly decreased the testosterone and LH of male rats. The colorectal, pancreatic, and ovarian cancer markers, and prostate specific antigen levels were significantly elevated after administration of MD and HD of MSG for 2, 4, and 6 months. This study has shown that the high dose administration of monosodium glutamate and soya bean produced delecterious effects on the biochemical parameters and cancer markers on rats after six months extensive administration.Item Open Access Determination of some algebraic properties of basarab loops(Federal University of Technology, Owerri, 2021-12) Effiong, Gideon OkonBasarab loops are non-associative generalizations of groups and are classified as loops of non Bol-Moufang type. They are G-loops with deep algebraic and structural properties. Not much were known about the form of isotopes, holomorphs, associators, center, and subloops of Basarab loops. This work was to determine some algebraic properties of Basarab loops. The objectives of the study were to construct a Basarab loop, investigate the relationship between Basarab loop and other loops like conjugacy closed loop, abelian inner mapping loop, and Osborn loop, examine the isotopes of a Basarab loop, investigate the holomorphs and associators of a Basarab loop, and characterize some subloops of a Basarab loop. Basarab loop identities were considered and some algebraic properties of loops were investigated. Loop notions such as the use of parentheses, multiplication group, isotopy theory, and holomorphy theory, total multiplication group were examined on a Basarab loop through the governing laws of Basarab loop. Some constructions of Basarab loops were given and some algebraic properties of Basarab loops were determined. The results obtained have shown that the centrum of a Basarab loop is a subloop and it is equal to the center of a Basarab loop, and that a Basarab loop with the left (right) inverse property, or inverse property is an extra loop. Necessary and sufficient conditions for isotopes and principal isotopes of a Basarab loop were determined. It was proved that every principal isotope of a Basarab loop is a Basarab loop. It was proved that any Osborn loop is a Basarab loop if and only if it is a left (right) Basarab loop. Also, the holo morphs of a Basarab loop were investigated by considering a group A(Q) of automorphisms of a loop. Some necessary and sufficient conditions for an A(Q)-holomorph of a loop (Q, ·) to be left (right) Basarab loop, and Basarab loop were established. Some left (right) translation mapping of the holomorph of a left (right) Basarab loop was shown to be left (right) regular. It was shown that an A(Q)-holomorph of a loop (Q, ·) which satisfies the inverse property is a Basarab loop if and only if (Q, ·) is a Basarab loop and every automorphism of Q is nuclear.Some subloops of a Basarab loop which are characterized by permutations were obtained. It was proved that a Basarab loop is a centrum-abelian inner mapping loop. Relationship betweenassociators and inner mappings of a Basarab loop was defined. It was shown that the associator of any three elements of a Basarab loop is contained in the center and centrum of a Basarabloop. This study has presented additional properties of Basarab loops which are now available for applications. Therefore, it is recommended that researchers and cryptographers should usethe properties of Basarab loops determined by this study for further research and applications.Item Open Access Hybrid deep learning-based model for covid-19 prediction and interpretation using multiple data modalities(Federal University of Technology, Owerri, 2024-05) Dokun, OyewoleThis research addresses the critical need for accurate and timely COVID-19 diagnosis and prognosis by developing a hybrid deep learning model that integrates multiple data modalities, including chest X-rays, Computed Tomography (CT) scans, blood smears, and clinical data. The model employs specialized architectures such as Residual Network with 50 Layers (ResNet50) for Chest X-ray, InceptionV3 for CT scans, Convolutional Neural Network (CNN) for blood smears, and a Random Forest classifier for clinical data analysis. The results demonstrate high accuracy rates: 96.7% for ResNet50, 97.58% for InceptionV3, 96.12% for CNN, and 98.30% for the Random Forest classifier. Grad-CAM enhances transparency by visualizing critical regions in the images, aiding healthcare professionals in understanding the model's decisions. This hybrid model offers improved accuracy and reliability for COVID-19 diagnosis and prognosis, making it a valuable tool for clinical settings and resource allocation. The research underscores the potential of multi-modal data integration in medical AI and suggests further exploration and refinement of such models for broader healthcare applications.Item Open Access Intelligent evaluation system for software quality measurement(Federal University of Technology, Owerri., 2022-12) Nwandu, Ikenna CaeserThe concern about the large-scale and complexity of contemporary software cannot be over-emphasized. This is inclined to the assurance of standardized software quality which is essential for preventing disastrous effects of releasing fault-prone systems. This thesis designed an intelligent model that uses various metrics corresponding to six quality attributes (namely Reliability, Usability, Efficiency, Functionality, Maintainability and Portability) to measure the quality of software. This agreed to the assertion that software quality evaluation process is an instrument that observes the characteristics of a software product. In software engineering, the primary quality evaluation and assurance technique that establishes confidence over successful execution of software is termed software testing. Software testing usually identifies and applies metrics to software products in order to promote and assess their quality. This thesis designed an intelligent evaluation model in conformance with software testing principles. The objective of the model is to apply reinforcement learning in its software evaluation process to measure six software attributes in terms of speed of execution and to ensure optimal decision-making in the evaluation process, such that the model returns a reliable outcome. The model utilized a formulated model equation, whose input are the measured attributes, to achieve the evaluation. The model is developed using extreme programming principles, an agile framework whose operation is based on simplicity. It also adopted object-oriented analysis and design methodology which allowed the utilization of various artifacts including use cases, data flow, sequence, flowchart, entity-relationship and class diagrams to describe the architecture and functionality of the system. The model was implemented using Python programming language with the database design on MySQL platform. The model is further validated by comparing its performance measures on test data gotten from the functional information of Oil-palm Management Program and Estate CanePro. These tests data produced quality values of 0.9 and 1.0 respectively via the model equation. These results gave the indication that the resource software perform efficiently owing to the fact that the model’s value benchmark is best as it approaches unity. The result of comparing the outcomes showed that reinforcement learning makes software evaluation dynamic and precise. The results indicated that the model independently determines the strategies to follow during evaluations and the same set of data consistently gives the same outcome. The result also showed that the reliability of a software is directly proportional to its usability and maintainability. However, the result also showed that having a high portability value does not guarantee the reliability and/or maintainability of a given software.Item Open Access Modelling of Nigeria’s Liquefied Natural Gas Shipping Trade(Federal University of Technology, Owerri., 2022-12) Igboanisi, Chinaemerem C.Nigeria has the largest proven natural gas reserves in Africa and its reserves ranked as ninth (9th) largest in the World- accounting for 188.8tcf (trillion cubic feet) of proven reserves as at the year 2019. However, Nigeria’s capacity to participate in the global natural gas shipping trade and earn freight revenue has been constrained by shipping tonnage market domination by other nations. Thus, as the nation strives to improve her revenue earnings through robust visible and invisible trade policy; it has become imperative to investigate empirically the determinants of Nigeria’s international shipping trade in Natural gas. This research developed the gravity model of Nigeria’s natural gas (NLNG) shipping trade to determine the factors affecting NLNG international freight market. The secondary data for the study comprised of volume of natural gas production (in billion cubic meters) shipped between Nigeria and other trading partner countries, geographical distance data between trading partner countries, population mass of trading partners, price of natural gas and bilateral trade agreements. Others include: logistics performance indices and shipping freight rates. These were sourced from global databases, Nigeria LNG limited, the Nigerian Ports Authority and covered the periods between years 2003 to 2020. To address the hypotheses governing this research, we developed an augmented gravity model of natural gas shipping trade in Nigeria’s international freight market and examined trends in demand. The following variables were found statistically significant in explaining NLNG trade namely: quality of transport infrastructure (-225.448), geographical distance (-232.721), trade agreement (42.534) and population mass (0.955). These coefficients are in their natural logs and can therefore be interpreted as elasticities. In terms of most important trading blocs or shipping routes, the most important shipping routes (which are dummy variables) are namely: The United States of America (3,360.056), EuroAsia (3,090.082), Europe (904.810) and South America (786.413). These findings indicate that robust policy interventions are needed to promote trade with our trading partners. Robust investments are also needed in our transport infrastructure quality (especially that of bunkering facilities for LNG vessels) in order to reduce impediments to trade. From the positive trend analysis results, demand for natural gas is positive and the federal government should encourage more private sector investment in LNG shipping fleet to increase Nigeria’s participation in LNG international freight market. As recommendation for further studies, modelling of constraints of natural gas trade involving gasification and re-gasification stations should be explored in order to expand the scope of the present work.