University of Ibadan Journals
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AVAILABILITY AND UTILIZATION OF LIBRARY-BASED ONLINE RESOURCES FOR LEARNING ACTIVITIES BY UNDERGRADUATES OF UNIVERSITY OF IBADAN, NIGERIA
Get PDFLibrary-based online resources are important due to their enormous benefits to students and university libraries. In particular, they offer students the opportunity to access current and relevant information from different subject areas. The purpose of this study was to investigate the availability and use of these resources for learning activities by undergraduates of the University of Ibadan, Nigeria. The descriptive survey design was adopted for the study and the population consisted of 12,173 full-time undergraduates. Stratified, proportionate, random sampling techniques were used, with a sampling fraction of 2.5%, to obtain a sample size of 303 students. The data collection instrument was the questionnaire titled “Availability and Utilization of library-based Online Resources For Learning Activities By Undergraduates (AULORLAU)” and data were analyzed using descriptive and inferential statistics consisting of frequency, tables, and percentages for the research questions, while Pearson Moment Correlation was used to analyze the hypothesis at 0.05 level of significance. The findings revealed that electronic journals were the most available (mean=2.9) and frequently (mean=3.3) used Library-based online resources among the undergraduates and ‘assignment’ was the main purpose for which they used these resources, while poor internet connectivity was their greatest challenge. There was a significant relationship between the availability of the resources and their utilization by the students (r=0.197; p<.05) Library-based online resources enhanced students’ learning in all academic disciplines, as the resources provided lecturers and students alike with vast quantities of information in an easily accessible non-sequential format. The study, therefore, recommended, among others, that university administrators and library management should make efforts to improve on bandwidth and enhance connectivity within the library premises so as to enable students to have easy access to the Internet
Asymptotic Behaviour of The Heat Equation as The Solution of The Black-Scholes Model
Get PDFWe carry out the reduction of the Black - Scholes equation via series of transformations toobtain the heat equation by reversing the direction of time,so that the pay-off of the Black-Scholes becomethe initial value condition of the heat equation.The solution of the obtained heat equation is generalizedas the solution of the Black-Scholes equation.Here we examine the 1-dimensional case and its extensionto the multi-dimensional case
Cubic Smoothing Spline on some Selected Blood Pressure Variables
Get PDFGeneralized Additive Model has become an elegant and practical option in modelling non-linear and linear effectsof covariates as well as the non-Gaussian response variable. This study considered modelling Blood Pressure (BP)using data with two levels of BP (abnormal and normal) and eight predictors which have both linear and non-lineareffects. The non-parametric functions were estimated in a flexible manner using cubic smoothing spline in aniterative method called the Back-fitting algorithm. The Cubic smoothing spline was applied to the metricalcovariates (Age and BMI), which gave significant results (p < 0.0001 and 0.0082 respectively) compared to thelinear fit which was not significant. The empirical findings of this study have established that BMI and Age havesignificant non-linear effect while sex and cholesterol level have significant linear effect on BP
3-D Seismic Structural Interpretation of a Part of Aloo-Field, Southwestern Niger-Delta, Nigeria
Get PDFComplexity of faulted subsurface configuration causing erroneous deductions in absence of well articulated interpretation approach led to a well refined 3D seismic data. Part of ALOO-Field located in offshore southwestern of Niger Delta was considered in this work. The study was aimed towards determining its subsurface structural features and retentive capacity of the reservoir for hydrocarbon. The methods employed include analysis of 3D seismic data using Petrel software; horizons and fault deductions. Seismic section were used to generate structural maps which revealed different structural styles present in the studied area. Three distinct horizons were mapped. Depth structural maps generated for all surfaces of interest show subsurface features such as the geometry of the identified horizons, W-E trending growth fault, fault echelons of which most of them dip to the east and fault assisted closures at the northwestern-central part of the studied section. The dipping pattern of the identified faults coincides with that of the growth fault which enhances trapping mechanism for the hydrocarbon. Two principal structural trapping mechanisms present are growth fault and rollover anticline which are synonymous with Niger Delta. The study has demonstrated the importance of seismic structural interpretation in understanding the structural styles present and their retentive ability for hydrocarbon
Essential Oil Composition of Three Compositae- Aspillia africana, Chromolaena odorata, Syndrella nodiflora and One Labiatae- Hyptis suaveolens Plants Commonly Utilized as Rabbit Feeds
Get PDFRabbits showed varied preferences in the order of their consumption of these four plants as meal: Syndrella nodiflora > Hyptis suaveolens > Aspillia africana > Chromolaena odorata. Chemical compositions with differences in levels of nutrients, palatability and odour may be responsible for the preferences observed. This study was targeted at examining volatile chemical constituents of both leaf and stem (parts utilized as meal) essential oils, which are likely responsible for the preferences observed. GC and GC-MS analyses conducted on eight essential oil samples revealed thus: Nine major compounds were responsible for 59.8 % of Syndrella nodiflora leaf essential oil. In its stem essential oil, twelve compounds which account for 40.5% of the oil were identified, these were dominated by terpenes (28.4%). Fifteen compounds were identified in leaf essential oil of the second preferred plant meal- Hyptis suaveolens, and was dominated by terpenes (61.3%), its most abundant compound being p-cineole (17.6%). Thirteen compounds make up 76.2% of its stem oil, two of which are yet to be identified; Seven (77.7%) and nine (75.7%) compounds were identified respectively in the leaf and stem volatile oils of Aspillia africana the third preferred plant meal. Its leaf oil is dominated by ?-bisabolol (46.4%), while terpenes make-up 70.4%. The stem oil has its most abundant compound to be (+) D-nerolidol (17.5%). Other interesting classes of compounds in the stem oil include hydrocarbons (23.5%), acid (9.1%) and alcohol (6.3%); Thirteen compounds each were identified in leaf and stem oils of Chromolaena odorata, the least preferred plant as meal by the rabbits, these compounds account for 57.3% and 72.3% of the oils respectively. Caryophyllene oxide (11.4%) is the dominant compound in leaf oil, while the stem oil is 3Z-3-heptadecen-5-yne (13.6%). Both oils are characterized with the dominance of terpenoids (45.4% and 47.3% respectively). Our results fully agree with compositions of the oils that have been reported in literature. This study presents compositions of stem essential oils of Syndrella nodiflora, Hyptis suaveolens and Chromolaena odorata for the first time
Determination of the pKa values of some selected aromatic amines and naturally occurring compounds in polar and non-polar solvents at 25oC
Get PDFIonisation constant is a measure of the strength of acids and bases and is expressed in terms of the pKa of conjugate acidsand bases. The pKa of naturally occurring khivorin, 7-keto-khivorin and some aromatic amines were measured in chloroform,toluene, 50% ethanol-methanol, 50% ethanol-water and 75% ethanol-methanol mixture at 25oC by potentiometric titration.The pKa values obtained are 3.23 for khivorin in toluene and 1.20 for 7-ketokhivorin in chloroform which demonstrate theiracidic nature. The aromatic amines: indole and 4-dimethylaminopyridine have a higher pKa values in 50% ethanol-watersolvent compared to their values in ethanol-methanol solvents. 3-methylindole and para-toluidine have a higher pKavalues in 50% and 75% ethanol-methanol solvents than in ethanol-water solvent. The higher pKa values of indole and 4-diemthylaminopyridine in 50% ethanol-water signifies the best medium at which the strength of these amines could bedetermined; whereas p-toluidine is best determined in 50% ethanol-methanol and 3-methylindole in 75% ethanol-methanolmixture
Subsistence of four bacteria isolated from Nigerian aquaculture farms on oxytetracyclineor
Get PDFThe ability of 147 oxytetracycline (OTC)-resistant bacteria isolated from aquaculture ponds in Ibadan, Nigeria, to subsiston OTC as a source of nutrient for growth was investigated in this study. Four bacteria identified by 16S rDNA sequencingas Bacillus pumilus Aa8, Bacillus pumilus Ab11, Stenotrophomonas maltophilia Ng7 and Klebsiella pneumoniae Nf6utilised 4.8, 13.1, 16.5 and 19.0 % of the OTC supplied in the growth medium in 72 hours with degradation rates of 8.0, 21.8,27.5 and 31.7 ?g/day respectively. The results showed that bacteria capable of subsisting on tetracycline (TET) antibioticsare present in the environment. However, the risk of possible transfer of resistance determinants to other environmentalbacteria by these strains is a disincentive to their use in the clean-up of antibiotic contaminated ecosystems
Grid-Based Prediction model for Coronary Heart Disease: Using Data Generated from the IoT-based Health Monitoring Systems
Get PDFAbstract
Internet applications are now closely associated with human life and hence, have become inevitable in human daily activities. This has resulted in the deployment of various types of sensors and computing devices in huge numbers. One of such is the network of objects which are interconnected to create and share data, called the Internet of Things (IoT). Amongst the applications enabled by the Internet of Things, the continuous health monitoring system (HMS) is a particularly important one. Therefore, this study was carried out to design architecture on fog network, that acquires data from IoT-based Health monitoring systems using Radio Frequency Identification-RFID, and develop a prediction model that predicts coronary artery disease using Artificial Neural Network. The existing heart disease datasets from the UCI Machine Learning Repository was used. In our result, the confusion matrix, in the order of (True Positive, False Positive, True Negative, False Negative) gives 41%, 8%, 40.3%, 10.6% respectively. Equal Error Rate: 0.1867, Accuracy: 0.8132, Sensitivity: 0.7939, and Precision: 0.8362. Finally, Receive Operative Characteristic (ROC) gives 0.8034. Having fully explored and implemented this model, the performance of our model was examined and compared with another work and we found out that our model out-performed the model in terms of accuracy and precision
Electrocardiogram Signal Analysis Using Artificial Neural Network
Get PDFThe electrocardiogram (ECG) is the electrical manifestation of the contractile activity of the heart and can berecorded fairly easily with surface electrodes on the limbs and chest. It is the most commonly known, recognisedand used biomedical signal. ECG wave shape is altered by cardiovascular diseases and abnormalities such asmyocardial ischemia and infarction, ventricular hypertrophy, and conduction problems. For the ECG analysis, themethod adopted involved extracting features that represent the ECG signals. Eight sets of ECG signals were used.This was achieved by extracting the QRS complexes within the ECG data first and finally using feature extractionscheme, to extract key features: Spectral Entropy, Pointcare plot geometry and Largest Lyapunov Exponent (LLE)that were used to train an Artificial Neural Network (ANN) model. The ANN model thereafter classified the ECGsignals into eight key classes. The analysis showed a very good match from the extracted features after trainingthe ANN model. The chosen features gave a 100% match when tested against known ECG data samples.Performance analysis was performed using a confusion matrix to describe how well the classification modelperforms in classifying the ECG data. The study was able to achieve the set objective in classifying the cardiacdisorders correctly into their respective classes; showing 90.6% and 97.7% accuracies for two-thirds and 90% ofdata used, respectively
Utilization of ICT Software Resources for Business, News, Education and Health Before and During Coronavirus Outbreak in Nigeria
Get PDFThis work carried out a comparative study on the utilization of ICT resources (software and radio/televisionbroadcast) for applications such as business, news, education and health before and during coronavirus outbreakin Nigeria. Borgu local government, Niger state was purposively selected for the study. The study adopted surveymethod of enquiry in which selection of participants in the study area has only one inclusion criteria which isinterest in participating in the survey. A self-constructed software resources utilization questionnaire (SRUQ) wasadministered via Google form to the interested participants in the study area and the responses retrieved werestatistically analysed. The results obtained showed decreasing utilization order for software resources (?[eeducation]>?[e-news]>?[e-business]>?[e-health]) and decreasing utilization order (?[e-news]>?[eeducation]>?[e-health]>?[e-business) for radio/television broadcast. It was also found that utilization of softwareresources for all itemised applications increased but not significantly (p>0.5) and while that of radio/televisionbroadcast increased significantly (p<0.5) during coronavirus outbreak. Moreover, radio/television broadcastpossessed significantly higher utilisation for all applications as compared with software resources before andduring coronavirus outbreak. It was therefore recommended that relevant agencies take necessary steps that wouldafford proper utilization of software resources for national development as witnessed in the developed countries