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4DS OF CURRICULUM MODEL, SUSTAINABLE DEVELOPMENT GOALS, AND CURRICULUM ON EDUCATION FOR SUSTAINABLE DEVELOPMENT.
(2016) OGUNFOLAKAN, B.A
Most archaeological works in southwestern Nigeria are concentrated in Ile-Ife, Esie, Old Oyo and Owo. In these areas, the focus of archaeological studies had been on different works of art in bronze, terracotta, wood and stone. Studies on cultural themes related to the issues of conflict, war and displacement which have implications for landscape archaeology of the area are often relegated to the background. The main goal of this research was to highlight how conflict, war and displacement impacted on the settlement history of parts of Osun State, southwestern Nigeria. The study also appraised human interactions with the environment and the concomitant effects on emergent settlement configurations. Oral and written data were collected from Ile-Ife, Ikire, Ipetumodu, Ila-Orangun, and Ajaba to generate anthropological data. Investigations aimed at identifying and collecting surface artifacts involved reconnaissance and detailed surveys of the studied sites. Excavations were carried out on potsherd pavements at Ajaba and Asi and on a refuse mound at Ajaba. Artifacts from surface collections and excavations were classified according to types, decoration and functional attributes. Analysis of Mo, Cu, Pb, and Ni of sherd samples was done using inductively coupled plasma mass spectrometry. Ten thin sections were made from selected sherd samples for determination of pottery fabric and inclusions. Palynological analysis of soil samples collected from different depths of the excavated mound was carried out using a microscope with an attached camera. Decorative motifs such as single twisted cord impression were common to all sites. With exception of sherds from Ila-Orangun, those from other areas were related in terms of types, fabric and functional attributes. Some of the sherds bore striking resemblance to those documented for Old Oyo and Ile-Ife with regard to type, decoration and function. Stylistically, the potsherd pavements at Asi and Ajaba were similar to those documented for Ile-Ife. A C-14 date of AD 1263 was obtained from charcoal at a depth of 80cm from the Ajaba mound excavation. Maize cob decoration was absent which indicated that Ajaba site was occupied prior to 16th century when maize was introduced into West Africa. Pollen of forest species and ornamental plants of Asian origin, such as Lagerstroemia indica, Casuarina equisetifolia and Delonix regia was identified from the excavated mound. These were abundant at the lower levels of the excavated mound. However, pollen of ornamental plants disappeared completely at the upper levels while secondary forest species and artifacts increased in abundance which was indicative of increase in human population and subsequent impact on vegetation. There was evidence of increased peopling of the area from around AD 1263. Oral and written records suggested that conflicts and war caused displacement and re-occupation of most of the settlements. Conflict and war resulted in the abandonment and reoccupation of all the sites, resulting in the delineation of several historical phases of occupation. Human impact on the environment was noted from the 13th century.
Additive effects of ciprofloxacin on the in-vitro activity of chloroquine against a clinical isolate of Plasmodium falciparum
(Taylor & Francis, 2006) Kazzim, O. J.; Adegbolagun, O. M,; Osho, O.; Anumudu, C. I.
As chloroquine and ciprofloxacin each possess substantial inhibitory activity against the schizonts of Plasmodium falciparum, it seems possible that a combination of the two drugs may be clinically useful. The effects on the erythrocytic stages of P. falciparum of combined treatment with chloroquine and ciprofloxacin were therefore evaluated in vitro, using the World Health Organization’s standardized micro test. When used alone, the median inhibitory concentration (IC50) of chloroquine against the schizonts in the assay mixtures was found to be 7.75 mg/ml, whereas the corresponding value for ciprofloxacin was markedly lower, at 3.35 mg/ml. When they were used together, however, there was marked and statistically significant mutual enhancement of schizont inhibition by the two drugs, indicating that a chloroquine–ciprofloxacin combination may be useful clinically, in the treatment and management of P. falciparum malaria.
An adjusted network information criterion for model selection in statistical neural network models
(JMASM, Inc., 2016) Udomboso, C. G.; Amahia, G. N.; Dontwi, I. K.
In this paper, we derived and investigated the Adjusted Network Information Criterion (ANIC) criterion, based on Kullback’s symmetric divergence, which has been designed to be an asymptotically unbiased estimator of the expected Kullback-Leibler information of a fitted model. The ANIC improves model selection in more sample sizes than does the NIC.
An algoritm for solving electromagnetic field equations by finite element method
(Medwell Journals, 2007) Adetoyinbo, A. A.; Adewole, O. O.
Describing the behaviour of electromagnetic frequency responses from vertically inhomogenous and anisotropic earth of 2-Dimensional structures energized finite sources is computationally laborious. Differential equations were derived and their numerical solutions also sought for the desired components of electric and magnetic fields. Also, expressions for the impedance and apparent conductivity were stated. An algorithm based on the finite element method for computing approximate numerical solutions for these problems were dealinated.
Alternative goodness-of-fit test in logistic regression models
(Medwell Journals, 2011) Nja, M. E.; Enang, E. I.; Chukwu, A. U.; Udomboso, C. G.
The Deviance and the Pearson chi-square are two traditional goodness-of-fit tests in generalized linear models for which the logistic model is a special case. The effort involved in the computation of either the Deviance or Pearson chi-square statistic is enormous and this provides a reason for prospecting an alternative goodness-of-fit test in logistic regression models with discrete predictor variables. The Deviance is based on the log likelihood function while the Pearson chi-square derives from the discrepancies between observed and predicted counts. Replacing observed and predicted counts with observed proportions and predicted probabilities, respectively in a cross-classification data arrangement, the standard error of estimate is proposed as an alternative goodness-of-fit test in logistic regression models. The illustrative example returns favourable comparisons with Deviance and the Pearson chi-square statistics.
An alternative technique to ordinal logistic regression model under failed parallelism assumption
(2009-12) Adeleke, K.A .; Adepoju, A.A
Maternal health status is often measured in medical studies on an ordinal scale but data of this type arc generally reduced for analysis to a single dichotomy. Several statistical models have been developed to make full use of information in ordinal response data, but have not been much used in analyzing pregnancy outcomes. The authors discussed two of these statistical models the ordinal logistic regression model and the multinomial logistic regression model. Logistic regression models are used to analyze the dependent variable with multiple outcomes which can either be ranked or not. In this study, we described two logistic regression models for analyzing the categorical response variable. The first model uses the proportion-! odds model while the second uses the multinomial logistic regression model. The fits of these models using data on delivery from a Nigerian State hospital record/database were illustrated and compared to study the pregnancy outcomes. Analyses based on these models were carried out using STATA statistical package. The Multinomial logistic regression was found to be an important alternative to the ordinal regression technique when proportional odds assumption failed. The weight of the baby and the mother's history of disease (treated or not treated) were found to be important in determining the pregnancy outcome.
Analysis of aquatic insects’ communities of Awba reservoir and its physico-chemical properties
(Maxwell Scientific Organization, 2011-06) Popoola, K. O. K.; Otalekor, A
This study was conducted to assess the Awba reservoir insects’ communities and the health status through the determination of insects’ abundance, composition, distribution and water qualities parameters. Water samples and insects were collected bi-weekly from August through December, 2009. Insects were sampled using standard entomological methods, while water samples was analyzed using standard Winkler’s titrimetric and APHA methods to determine the chemical properties. Water analyses and insects’ identifications were conducted in the laboratory in Department of Zoology, University of Ibadan, Oyo State. The results show that only DO and phosphate-phosphorus had significant difference (p<0.05). A total of 1,154 insects were recorded, Chironomidae and Culicidae were most abundance. The chemical properties and the distinct taxa found in the water suggest that the water body is polluted and may be dangerous to the health of people around the reservoir.
Analysis of heavy metals concentration in sediments and water samples of selected functional dams in Oyo State, Southwestern Nigeria
(2008) Adegoke, J. A.; Sunmonu, L. A.; Ojeniyi, O. S.
"The quality as well as the quantity of clean water supply is of vital significance to the welfare of mankind particularly in the developing countries. Therefore, knowing the concentration of heavy metals present in Dams can help us to ascertain the health safety of the populace using the water for drinking and domestic purposes. Ten Dams at Oyo State in the Southwestern Nigeria were studied for the heavy metals concentration contained in the sediments and water of the selected Dams. Bottom sediments and water were collected from the selected dams for analysis. Analysis of both the water and sediments to determine the concentration of each heavy metal was evaluated. The result obtained shows that, the concentration of Manganese (Mn) ranges from 14.8 mg/kg to 332.96 mg/kg followed by Zinc (Zn) which ranges between 6.18 mg/kg and 52.53 mg/kg which spread across all locations., Lead (Pb) was not detected in virtually all the locations except in Ilora which has a concentration of 0.87 mg/kg and this may be as a result of the activities of motor mechanics and vulcanizers around the dam. In the water samples, the result showed that the concentration of heavy metals is very low which is far below the limit specified by World Health Organization (WHO). Zn has the highest concentration ranging from 0.049mg/kg to 0.729mg/kg, followed by Mn which has concentration between 0.011mg/kg and 0.344mg/kg. Pb, Cadmium (Cd) and Cobalt (Co) were not detected at all in all the water samples. The variation in the concentrations may be due to geological nature of the ground, solubility, an ion exchange and human activities. "
Angiotensin II type 1 receptor A1166C gene polymorphism and essential hypertension in the Efiks of Calabar
(Academic Journals, 2009) Kooffreh, M. E.; Anumudu, C. I.; Akpan, E. E.
Hypertension is a multifactoral disorder because of the interaction of risk genes and environmental factors. The angiotensin II is a well known vasoconstrictor that exerts most of its influence through the angiotensin Il type 1 receptor The A 1166C polymorphism is a single base substitution of adenine for cytosine at position 1166 in the 3' untranslated region of the gene. There are conflicting reports on the association of the Al166C polymorphism with cardiovascular diseases such as prevalent hypertension, left ventricular hypertrophy, and pregnancy induced hypertension. These variations were attributed to ethnic differences in different populations. We investigated the association of the All66C polymorphism with hypertension in 100 individuals from the Efik tribe who were matched for gender and sample size. PCR-RFLP analysis was carried out to determine the allele frequency of the gene. The genotype frequencies were 48, 2 and 47, 3 for the AA, AC genotypes respectively in the patient and control groups. No individual with the CC genotype was observed in the study population. The frequency or the C allele was 0.03 and 0.02 in the control and the patient population. The genotype and allele frequency did not conform to the Hardy-Weinberg theory. Using regression analysis, age and diastolic were positive predictors for SBP, r=0.0.50; systolic was the only predictor for DBP in the patient group. Diastolic was the only predictor for SBP, r= 0.656 while age and systolic were positive predictors for DBP r= 0.718 in the control group. Gender, BMI, Al166C polymorphism and other independent varilables were not predictors for SBP and DBP in the population. P= 0.05, odds ratio 0.65, 95% CI (0.13 to 3.44). The Al166C polymorphism is not an independent risk factor for essential hypertension in the study population.
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.
Anopheles gambiae complex: Molecular forms and occurrence of the KDR gene in rural Southwestern Nigeria
(Ibadan, Entomological Society of Nigeria, 2011) Noutcha, M. A. E.; Anumudu, C. I.
An investigation focusing on the molecular forms of Anopheles gambiae complex and occurrence of the knockdown resistance (kdr gene) was carried out from June to July 2001 and August to September 2002 at Igbo-Ora, Nigeria usirig aspirator and DNA analyses. Of the 127 An. gambiae s. l. analysed, there were 66 (51:9%)M and 61 (48.03%) S forms, both recorded in An. gambiae s.s. and Anopheles arabiensis. The forms were virtually sympatric throughout the study. Two of the An. gambiae s.s. examined harboured the kdr gene (RR, RS). The occurrence of the kdr gene at Igbo-Ora indicated the existence of the gene in the savanna woodland populations; earlier records were from the rain forest and Guinea savanna. The implications of these results, within the context of incipient speciation in Anopheles gambiae s.s. are discussed.
AN ANTHROPOLOGICAL STUDY OF THE ABO BLOOD GROUP DISTRIBUTION AMONGST THE YORUBA OF NIGERIA
(1994-06) ADEKOYA, B. B.
Twenty-five (25) sub-groups of the Yoruba language sub-family in Nigeria were identified based on such similarities as: territory, dialect, descent, cultural and economic ties. The ABO blood group samples and records of the identified Yoruba sub-groups were analysed and evaluated. These Yoruba sub-groups included: Akoko, Akure, Awori, Bunu, Egba, Egbado. Ekiti, Eko, Ibarapa, Ibolo, Ife, Igbomina, Ijebu, Ijesa, Ijumu, Ikale, Ilaje, Ilorin, Kabba, Ondo, Owo, Owu, Oyo, Remo and Yagba. Frequency distribution and percentiles of the ABO blood groups in each Yoruba sub-groups were determined through statistical analysis and subjected to X2 distribution analysis to detect deviation significance levels about the expected mean of ABO blood groups for the Yoruba language sub-family. The majority of the individual blood group types within the Yoruba sub-groups were of the type 'O'. Percentiles and frequencies for this blood group type for each Yoruba sub-group exhibited two distinct mean pulses. The mean percentiles for the type 'O' blood group were 51.6% and 55% with mean frequency values of 0.718 and 0.742 respectively, indicating the presence of two dialect groups within the Yoruba language sub-family. The Yoruba sub-groups hereby identified from the ABO blood sample analysis and subseguently classed into two dialect groups coincide with the "i" and "u" linguistic dialect areas into which the Yoruba territory of Nigeria is divided, thus confirming the existence of a definite anthropological divide of the Yoruba language sub-family.
ANTI-MOSQUITO PROPERTIES OF METHANOL EXTRACT OF Clerodendrum polycephalum Baker
(2018-02) ADEWOYIN, F.B
ABSTRACT Mosquitoes are vectors of various diseases of public health importance and their control has been premised on the use of synthetic insecticides. However, these insecticides are laden with problems of high cost, environmental hazards and development of resistance in many species of mosquitoes. Alternatives to synthetic substances are the natural products. Plant species, Clerodendrum inerme, have been found to inhibit the growth of Aedes aegypti and Culex quinquefasciatus larvae. However, there is paucity of information on the anti-mosquito properties of the Nigerian species, C. polycephalum Baker. Therefore, the aim of the study was to investigate the anti-mosquito properties of the methanol extract of the leaves of C. polycephalum. Fresh leaves (1.4 kg) of C. polycephalum were harvested and brought to the laboratory. The leaves were air-dried, powdered, extracted with methanol and concentrated to dryness using rotary evaporator. The crude methanol extract was subjected to phytochemical analysis according to standard method and separated into n-hexane, dichloromethane, ethyl acetate and ethanol fractions using vacuum liquid chromatography. The most active fraction (ethanol), was subjected to column chromatography. Gas Chromatography - Mass Spectroscopy (GC-MS) was used to analyse the subfraction which was ultra-violet active. The crude methanol extract and fractions (250–8000 ppm) were tested for larvicidal activity. The methanol extract was further tested for anti-oviposition, effects on growth and development on Aedes aegypti, Anopheles gambiae and Culex quinquefasciatus mosquitoes together with corresponding positive (lambda-cyhalothrin) and negative controls (dimethylsulfoxide) using World Health Organisation procedures. Toxic effects, determined by mortality, on representative non-target organisms was evaluated on adult Biomphalaria glabrata (snail) and tadpoles of Bufo regularis. Ten each of the organisms were used per concentration. Data were analysed using descriptive statistics and student’s t-test at α0.05. Tannins, flavonoids, saponins and alkaloids were identified from the crude extract. Seventeen compounds were detected from ethanol subfraction, with quantities varying from 0.0 to 23.7%. Prominent compounds include 4-((1E)-3-Hydroxy-1-propenyl)-2-methoxyphenol (7.5%), 2-Hydroxy-5-methylbenzaldehyde (6.1%) and Ethyl iso-allocholate (23.7%). Larvicidal activities of crude methanol extract and fractions were in the order ethanol (100.0%) > methanol (96.6%) > n-hexane (7.5%) > DCM/ethyl-acetate (0.0%) at 2000ppm after 24h. Susceptibilities of mosquito larvae to methanol extract were also in the order A. aegypti > A. gambiae > C. quinquefasciatus. Mortality of the larvae was significantly different from the positive control. Anti-oviposition index increased (46.4-89.9) with extract concentrations. Morphological deformities of larvae and pupae were observed at the higher doses of 2000 ppm (A. aegypti), 5000 ppm (A. gambiae) and 7000 ppm (C. quinquefasciatus). Mosquito adult emergence inhibitions (24.0-100.0%) were recorded at 1100–5600 ppm concentration levels. The crude extract had no effect on the tadpoles at 250–1000 ppm, but the mortality of the snail at 250–2000ppm, varied from 10.0–95.0%. Clerodendrum polycephalum leaves contained biological components capable of inhibiting the survival and development of mosquitoes and could be exploited in the control of mosquitoes.
Anti-nutritional status of uninfested and prostephanus truncatus (horn) (coleptra: bostichidae) infested dried cassava chips
(Maxwell Scientific Organization, 2015-04) Popoola, K. O. K.; Opayele, A. V.; Nkpondion, N. N.
This research study focus on the determination of anti-nutritional content status of the uninfested and infested dried cassava chips by Prostephanus truncatus. Prostephanus truncatus, the larger grain borer, is an alien invasive post harvest pest; with wide spread population all over cassava growing regions. After an infestation period of 10 weeks in the laboratory, proximate analysis revealed increased values for only alkaloids content in the infested dried cassava chips, while all other contents, such as hydrogen cyanide, saponin, tannin, trypsin inhibitor, oxalates and phytate had reduced values when compared to the un-infested dried cassava chips which recorded less anti-nutritional contents.
Antibacterial activities of daldina concentrica
(2011-01) Jonathan, S. G.; Olawuyi, O. J.; Popoola, O. O.; Aina, D. A.
Activities of the distilled water, ethanolic and chloroform extracts of Daldina concentrica an ascomycetous fungus was investigated on Escherichia coli, Proteus mirabilis, Pseudomonas aeruginosa, Bacillus cereus and Staphylococcus aureus) using agar well diffusion method. Ethanolic extract of Daldina concentrica showed significantly antibacterial activity against all the test microorganisms except Bacilllus cereus (P ≤0.05). Staphylococcus aureus was the most sensitive organism to the extracts of this fungus with 17.0mm zone of inhibition with ethanol extract. It was also shown that chloroform extract of Daldinia concentrica possessed higher anti-bacterial activity against the five tested microorganisms. The effect of fresh tissues of the fungus on test bacteria indicated that Proteus mirabilis was the only sensitive organism with 5.0mm zone of inhibition while other bacteria were resistant. The implications of these findings were discussed.
Antibody specificities of children living in a malaria endemic area to inhibitory and blocking epitopes on MSP-119 of Plasmodium falciparum
(Elsevier, 2009) Omosun, Y. O.; Adoro, S.; Anumudu, C. I.; Odaibo, A. B.; Uthiapibull, C.; Holder, A. A.; Nwagwu, M.; Nwuba, R. I.
Merozoite surface protein-119 (MSP-119) specific antibodies which include processing inhibitory, blocking and neutral antibodies have been identified in individuals exposed to Plasmodium falciparum. Here we intend to look at the effect of single and multiple amino acid substitutions of MSP-119 on the recognition by polyclonal antibodies from children living in Igbo-Ora, Nigeria. This would provide us with information on the possibility of eliciting mainly processing inhibitory antibodies with a recombinant MSP-119 vaccine. Blood was collected from children in the rainy season and binding of anti-MSP-119 antibodies to modified mutants of MSP-119 was analysed by ELISA. The MSP-119 mutant proteins with single substitutions at positions 22 (Leu→Arg), 43 (Glu→Leu) and 53 (Asn→Arg) and the MSP-119 mutant protein with multiple substitutions at positions 27 + 31 + 34 + 43 (Glu→Tyr, Leu→Arg, Tyr→Ser, Glu→Leu); which had inhibitory epitopes; had the highest recognition. Children recognised both sets of mutants with different age groups having different recognition levels. The percentage of malaria positive individuals (32–80%) with antibodies that bound to the mutants MSP-119 containing epitopes that recognise only processing inhibitory and not blocking antibodies, were significantly different from those with antibodies that did not bind to these mutants (21–28%). The amino acid substitutions that abolished the binding of blocking antibodies without affecting the binding of inhibitory antibodies are of particular interest in the design of MSP-119 based malaria vaccines. Although these MSP-119 mutants have not been found in natural population, their recognition by polyclonal antibodies from humans naturally infected with malaria is very promising for the future use of MSP-119 mutants in the design of a malaria vaccine.
Antibody specificities of children living in a malaria endemic area to inhibitory and blocking epitopes on MSP-119 of Plasmodium falciparum
(Elsevier, 2009) Omosun, Y. O.; Adoro, S.; Anumudu, C. I.; Odaibo, A. B.; Uthiapibull, C.; Holder, A. A.; Nwagwu, M.; Nwuba, R. I.
Merozoite surface protein-119 (MSP-119) specific antibodies which include processing inhibitory, blocking and neutral antibodies have been identified in individuals exposed to Plasmodium falciparum. Here we intend to look at the effect of single and multiple amino acid substitutions of MSP-119 on the recognition by polyclonal antibodies from children living in Igbo-Ora, Nigeria. This would provide us with information on the possibility of eliciting mainly processing inhibitory antibodies with a recombinant MSP-119 vaccine. Blood was collected from children in the rainy season and binding of anti-MSP-119 antibodies to modified mutants of MSP-119 was analysed by ELISA. The MSP-119 mutant proteins with single substitutions at positions 22 (Leu→Arg), 43 (Glu→Leu) and 53 (Asn→Arg) and the MSP-119 mutant protein with multiple substitutions at positions 27 + 31 + 34 + 43 (Glu→Tyr, Leu→Arg, Tyr→Ser, Glu→Leu); which had inhibitory epitopes; had the highest recognition. Children recognised both sets of mutants with different age groups having different recognition levels. The percentage of malaria positive individuals (32–80%) with antibodies that bound to the mutants MSP-119 containing epitopes that recognise only processing inhibitory and not blocking antibodies, were significantly different from those with antibodies that did not bind to these mutants (21–28%). The amino acid substitutions that abolished the binding of blocking antibodies without affecting the binding of inhibitory antibodies are of particular interest in the design of MSP-119 based malaria vaccines. Although these MSP-119 mutants have not been found in natural population, their recognition by polyclonal antibodies from humans naturally infected with malaria is very promising for the future use of MSP-119 mutants in the design of a malaria vaccine.
ANTIMICROBIAL AND ANTI – INFLAMMATORY ACTIVITIES OF EXTRACTS OF FICUS THONNINGII BLUME (MORACEAE)
(2014-05) COKER, M. E.
Infectious diseases and the associated inflammation pose a serious health problem worldwide, accounting for about 50% of all deaths in tropical countries. This is further complicated by the frequent development of bacterial resistance to many chemotherapeutic agents. These problems have necessitated the continuous search for new and effective drugs from plant materials. Thus, Ficus thonningii Blume (Moraceae), a plant used ethnomedicinally in West Africa for the treatment of some microbial infections, was studied for its antimicrobial and anti-inflammatory activities. Dried leaves and stem bark of Ficus thonningii were screened for secondary metabolites. Successive gradient extraction was carried out on the pulverised plant parts using hexane, chloroform and methanol with Soxhlet apparatus. Antimicrobial activity of the extracts on Gram-positive (10) and Gram-negative (11) bacteria, and fungal (12) isolates was evaluated using agar-diffusion method. Antibiogram of the microorganisms was determined using established antibiotics. Bioassay-guided fractionation of crude extracts using column chromatography was done. Minimum Inhibitory Concentrations (MIC) and minimum bactericidal concentrations of the crude extracts, fractions and isolated compound were determined by agar-dilution. Bactericidal kinetics of the methanol leaf extract against Staphylococcus aureus and Escherichia coli at 2.5-10.0 mg/mL were determined. Structure elucidation of the bioactive compound was carried out using 1H-NMR, 13C-NMR, DEPT 135, COSY, UV and GC-MS spectroscopy. In vivo anti-inflammatory activity of leaf extract was evaluated using carrageenan-induced rat paw oedema with acetylsalicylic acid as the reference drug. Acute oral toxicity, haematological and histopathological evaluations were carried out to determine the safety profile of methanol leaf extract in rats. Statistical analysis was carried out using Student’s t-test at p = 0.05. Alkaloids, flavonoids, terpenoids and cardiac glycosides were detected in the plant extracts. Antimicrobial assay of crude extracts and fractions showed a broad spectrum activity on sensitive and multidrug-resistant strains with the leaf and stem bark extracts having similar antimicrobial activity. Hexane leaf extract and bioactive fractions gave MIC range of 78-625 µg/mL and 20-625 µg/mL respectively while methanol leaf extract and bioactive fractions gave 156-625 µg/mL and 39-625 µg/mL. Structure elucidation of the bioactive compound isolated from hexane leaf fraction revealed a triterpenoid with MIC range of 20-156 µg/mL (Gram-positive bacteria), 39-156 µg/mL (Gram-negative bacteria) and 10-78 µg/mL (fungi), while that of gentamicin and tioconazole were 5-30 µg/mL and 10-20 µg/mL respectively. Methanol leaf extract showed bactericidal activity in a concentration-dependent manner on the microorganisms, with a 100% bactericidal action at 10 mg/mL on Staphylococcus aureus and 84% on Escherichia coli within 4 hours. The anti-inflammatory activity of methanol leaf extract was 57.5% while that of acetylsalicylic acid was 93.2%. Acute oral toxicity of methanol leaf extract showed an LD50> 5g/Kg. Significant increases were observed in the red blood cell count and mean corpuscular haemoglobin value, while histopathological evaluation revealed no significant tissue pathological changes in the major organs. Extracts of Ficus thonningii leaves contain antimicrobial and anti-inflammatory agents. These could be useful in the development of safe chemotherapeutic agents for the treatment of relevant microbial infections and inflammation-prone diseases.
An Application of Bayesian Dynamic Linear Model to Okun’s Law
(Scienpress Ltd, 2017) Awe, O. O.; Sanusi, K.A.; Adepoju, A. A.
Many authors have used dynamic time series regression models to analyse Okun’s law. This type of models often require first differencing the dependent and independent variables, as well as investigating the maximum lag length required for the model to be efficient. In this paper, we propose a straight-forward time-varying parameter state space model for analyzing Okun’s law. In particular, as a case study, we investigate the validity and stability of Okuns law using a Bayesian Dynamic Linear Model which implicitly describes the time-varying relationship between Gross Domestic Product (GDP) and unemployment rate of a major economy in Africa for three decades. The time-varying parameters of this model are estimated via a modified recursive forward filtering, backward sampling algorithm. We find that Okuns law exhibited structural instability in Nigeria in the period 1970-2011, with the sensitivity of unemployment rate to movements in output growth loosing stability over time, which may have been a contributor to her recent economic decline
Application of ordinal logistic regression model to occupation data
(Duncan Science Company, 2009) Adepoju, A. A.; Adegbite, M.
People's occupational choices might be influenced by their parents' occupation, gender, previous experiences, ages, and their own education level. We can study the relationship of one's occupation choice with education level and father's occupation. The occupational choices will be the outcome variable which consists of categories of occupations. The regression methods are capable of allowing researchers to identify explanatory variables related to organizational programs and services that contribute to the overall staff status. These methods also permit researchers to estimate the magnitude of the effect of the explanatory variables on the outcome variable. Therefore, regression methods seem to be superior in studying the relationship between the explanatory and outcome variables. This study used ordinal logistic regression method to examine the relationship between the ordinal outcome variable, different levels of staff status in the Lagos State Civil Service of Nigeria, the explanatory variables are Gender, Indigenous status, Educational Qualification, Previous Experience and Age. The outcome variable was measured on an ordered, categorical, and three-point Likert scale as Junior staff Middle Management staff, and Senior Management staff. Within the complete models, the legit link was the better choice because of its satisfying parallel lines assumption and larger model- fitting statistics. The study revealed that two explanatory variables namely, Education Qualification and Previous Working Experience significantly predicted the probability of an individual staff being a member of any of the three levels of staff status