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Identification and Pathogenicity of Fungi Responsible for Foliar Diseases of Groundnut (Arachis hypogaea L.) in Lafia
Get PDFFoliar diseases of groundnuts are important determinants of yield and productivity of the crop. The aim of this study was to identify and evaluate the pathogenicity of fungi responsible for foliar diseases of groundnut in Lafia. Tissues of groundnut leaves showing signs of discoloration, and spots, were cultured on potato dextrose agar (PDA) for isolation of in-dwelling fungi. A total of 48 isolates belonging to five genera, namely Fusarium, Rhizomucor, Curvularia, Epicoccum, and Aureobasidium were recovered. The identified species were Fusarium incarnatum, Rhizomucor spp., Curvularia lunata, Epicoccum nigrum, and Aureobasidium pullulans. Results of pathogenicity test showed that Rhizomucor spp. produced the highest leaf spots (60.00%), followed by Aureobasidium pullulans (55.00%), Epicoccum nigrum (30.00%), Curvularia lunata (16.67%), and Fusarium incarnatum (12.33%). However, differences in the severity of leaf spots caused by the different fungal pathogens were not significant (P>0.05). The study revealed that fungi isolated from symptomatic leaves of groundnuts were pathogenic, producing varying percentages of leaf spots on inoculated leaves. Therefore, there is a need to control fungal contamination of groundnut leaves in order to improve crop health and enhance yield of groundnuts
Impact of Gaussian Noise on the Optimization of Medical Image Registration
Get PDFGaussian noise often poses a significant challenge to medical image registration, impacting the accuracy and reliability of alignment across varying imaging modalities. The research investigates the effect of Gaussian noise on medical image registration by comparing four optimization techniques: a direct approach, an optimization using fmincon, a multiscale approach, and a combined optimization strategy that integrates fmincon and the multiscale approach. The comparative analysis assesses each method\u27s robustness against Gaussian noise, evaluating registration accuracy through three key similarity metrics: Mean Squared Error (MSE), Peak Signal-to-Noise Ratio (PSNR), and Structural Similarity Index Measure (SSIM). The results reveal that while each approach demonstrates a degree of resilience to noise, the combined optimization method significantly outperforms the others, achieving the lowest MSE, highest PSNR, and superior SSIM. These findings suggest that the combined approach effectively enhances the optimization process by leveraging the strengths of both fmincon and multiscale frameworks, thus providing a more accurate and noise-resistant solution for medical image registration. The analysis highlights the necessity of image filtering techniques to mitigate noise interference and improve the image registration process in clinical application
Machine Learning for detecting Microbial and chemical Contaminants in sachet Water
Get PDFThis study addresses the critical challenge of detecting microbial and chemical contaminants in sachet water in Nigeria using machine learning (ML) techniques. Traditional methods for water quality assessment are often time-consuming, costly, and ill-suited for real-time monitoring, particularly in resource-limited settings. We propose a novel approach that leverages supervised ML algorithms, including Gradient Boosting (GBC) and Random Forest (RF), to predict water potability based on an augmented dataset of 20 parameters, encompassing both microbial contaminants (e.g., Escherichia coli, Salmonella) and chemical contaminants (e.g., lead, arsenic). The dataset was enhanced using synthetic data generation techniques to address gaps in the original dataset, which lacked comprehensive coverage of critical contaminants. Our results demonstrate that the Gradient Boosting Classifier (GBC) achieves an accuracy of 99.8% and an F1 score of 99.7% on the augmented dataset, significantly outperforming other models. Feature importance analysis revealed that Escherichia coli, Salmonella, and lead were the most critical predictors of water potability, aligning with public health concerns. This study highlights the potential of ML for enhancing water quality monitoring, offering a scalable and cost-effective solution to mitigate waterborne diseases in regions like Nigeria, Nigeria. Future work will focus on integrating real-time sensor data and validating the model in real-world scenarios to further improve its applicability and impact
The Health Economics of Life Expectancy: Counting the Days before the Individual’s Roll Call
Get PDFFor a life office, the potential deviations from the mortality assumptions applied in premium setting at the time of incepting contracts represents serious threats to its financial performance when underwriting life insurance policies including annuities. Furthermore, in view of the uncertainties associated with the complete expectation of life evolving from the inadequately modelled life expectancy as a form of mortality risk indicator, this study explores the CMI’s generalized Makeham’s mortality law which would be advantageous to compute complete life expectancies. When continuous parsimonious parametric mortality intensities are Makehamized, then the limiting value of the continuous whole life annuity function is construed to mean the complete life expectancy which is expressed in line with special functions such as incomplete upper gamma function for a homogeneous insured population. In this study, the objective are to (i) construct actuarial estimation of individual’s time remaining through single life parameterization from GM(1,2) (ii) construct closed form expressions for complete life expectancy using the properties of the special functions as applicable in classical mortality dynamics. To circumvent the need for any rigorous numerical procedures, the advanced technique of the Gradshteyn and Ryzhik’s analytic integral is applied in computing the complete life expectancies. From our results, it is apparent that ex(male)< ex(female). Specifically, within the interval 111<x<119 for women, there is a sharp decrease in complete life expectancies whereas for men within the interval 75<x<119, life expectancies sharply decrease confirming earlier exposure of men to mortality risk
Malaria In Symptomatic Patients Attending A Federal Medical Centre In Central Nigeria
Get PDFMalaria remains an ongoing problem in Nigeria even though a lot has been achieved in the past years; millions of people are still at risk of contracting the parasite. Thus, this study determined the malaria prevalence in symptomatic patients attending a Federal Medical Centre in Central Nigeria. Five milliliters (5mls) of blood was collected from 250 patients between July and December 2023 by the use of a well labeled ethylene diamine tetraacetic acid (EDTA) vacutainer tube and malaria parasite test was conducted using microscopy and Rapid Diagnostic Test (RDT). Out of a total of 250 patients examined for malaria parasite in this study, 132 (52.8%) were significantly (P<0.05) positive to microscopy while RDT recorded 55 (22.0%) positive. Males had higher malaria prevalence of 61.3% in microscopy and 28.6% in RDT than 45.0% (microscopy) and 16.0% (RDT) recorded in females. Age groups, < 5, 5 – 10 and 50 and above years had the highest positive cases of 51.8%, 56.1% and 65.6%, respectively. A significant difference (P<0.05) was also recorded in relation to educational background, amongst rural and urban dwellers, and net usage status, respectively. The inhabitants of Keffi Local Government Area should observe regular sanitation to clear out all potential malaria vectors breeding grounds and avoid human-vectors contact by sleeping under long lasting insecticide treated bednets
Redox Kinetics and Mechanism of the Reactions of µ –Oxobis [aquobis (2,2’ – Bipyridine)] diruthenium (III) Ion and some Aliphatic Alcohols in Acidic Medium
Get PDFThe redox kinetics and mechanisms of the reactions of μ – oxobis[aquobis(2,2’ - bipyridine)]diruthenium (III) ion, [(bipy)2(H2O)RuORu(H2O)(bipy)2]4+ (hereafter denoted as Ru2O4+ or [(H2O)2(bipy)4Ru2O]4+) and some primary aliphatic alcohols was studied in perchloric acid medium, [H+] = 5.0 x 10-3 mol dm-3, ionic strength (I), = 0.5 mol dm–3 (NaClO4), temperature (T) = 31 ± 1°C and wavelength ,λmax = 660 nm. The reactions, which led to the formation of corresponding aldehydes had a stoichiometry of 1:1, were all first order with respect to each reactant, and second order overall. The reactions proceeded in the absence of acid but when acid was added, the reactions ceased. Varying the ionic strength and dielectric constants of the reaction medium had no effect on the reaction. Added ions catalysed the reaction and free radicals were identified in the reaction mixtures in the course of the reactions. There was no evidence for the formation if intermediate complex in the course of the reaction. The order of reactivity is of the order CH3OH > C2H5OH > C3H7OH Based on the results, it is suggested that all the reactions proceeded through the outer – sphere electron transfer mechanism and a plausible mechanism that represented all the reactions is proposed
Comparative Evaluation of the Proximate, Phytochemical and Antioxidant Properties of Selected Leafy Vegetables (Bitter, Pumpkin and Spinach Leaves)
Get PDFThe study is aimed at comparative evaluation of the proximate, phytochemicals and antioxidant properties of three leafy vegetables (V. amygdalina, Spinacia oleracea and Telfairia occidentalis).The study was carried out using standard analytical procedures. The proximate analysis revealed highest percent moisture (5.08±0.13%), crude protein (19.69±0.87%), carbohydrate (38.31± 1.42 %) and metabolizable energy (244.24±3.82 KJ/100 g) in pumpkin, highest percent ash (15.20± 0.86 %), %) and crude fat contents (8.30±0.18 %) in spinach, while bitter leaf recorded the highest percent crude fibre (20.01 ± 1.20%). The phytochemical analysis revealed the presence of flavonoid, saponin, alkaloid, tannin and phenol which ranged from 8.67±0.11 mg/100 g to 18.98± 0.15mg/100 g, 0.9±0.00 mg/100 g to 1.21± 0.10 mg/100 g, 8.87±0.21 mg/100 g to 11.65±0.68 mg/100 g, 0.81 ± 0.01 to 10.32± 1.2 mg/100 g and 1.36 ±0.01 mg to 4.24±0.01 mg/ 100 g respectively. The antioxidant activities revealed highest percent inhibition (71.20%) in bitter leaf. However, based on the analysis of variance on the results obtained, the study revealed that there were significant differences in most of the analyzed parameters at P ≥ 0.05. Therefore, this study inferred that the nutritional and phytochemical contents of the leafy vegetables samples varied significantly and their consumption in a diet will be responsible for maintaining good health and proper functioning of the body system
CUCURBITA PEPO FLOWER EXTRACT AS A CORROSION INHIBITOR FOR MILD STEEL IN ACIDIC MEDIUM
Get PDFAn investigation into the corrosion inhibition potentials of the flower of Cucurbita pepo was undertaken. The gravimetric and gasometric methods of corrosion measurements were employed at temperatures of thirty and sixty degree celcius. Ethanoic extract of the flower of Cucurbita pepo was used as a corrosion inhibitor in 0.5 M HCl and the results revealed that it mitigated the corrosion of mild steel in the acidic medium. The inhibition efficiency of the plant increased with concentration and it is temperature dependent. The experimental data fitted to the Temkin adsorption isotherm model. A mechanism of physical adsorption is proposed for the corrosion inhibition process. This work provides novel information on the possibility of using the flower of Cucurbita pepo as a corrosion inhibitor
CORRELATION ANALYSIS AND MODELLING OF HEAVY METAL CONCENTRATIONS AND PHYSICOCHEMICAL PARAMETERS FROM SOIL SAMPLES OF FIVE SELECTED REFUSE DUMPSITES IN LAFIA LOCAL GOVERNMENT AREA OF NASARAWA STATE, NIGERIA
No full textThousands of tons of solid wastes are generated and disposed daily in open dumps of most Nigerian cities due to rapid population explosion and commercial activities. In this study, concentrations of heavy metals and physicochemical parameters from 20 soil samples each from selected refuse dumpsites in wet and dry seasons were determined using Atomic Absorption Spectrophotometer and Association of Official Analytical Chemists (AOAC) standard methods. The results showed that during the wet and dry seasons, the concentration of heavy metals, Hg, Cr, Mn were above that of World Health Organisation (WHO), and National Environmental Standards and Regulations Enforcement Agency (NESREA), while that of Pb, As, Fe, Zn, Cu and Ni were below the tolerable limits. The results for physicochemical parameters in wet and dry seasons for nitrates, phosphates and organic matter were above WHO standards. Statistical test at 0.05 probability level (p < 0.05) was used to determine the degree of association between pairs of the variables. The principal component analysis (PCA) was performed to measure the direct and inverse relationship between these parameters and heavy metal availability. Based on the different variables obtained at the study areas, a multiple linear regression analysis was determined from which a general linear model was formulated. The study recommends appropriate government agencies should as a matter urgency integrate the regular monitoring of waste disposal into the state developmental plan and framework in order to prevent excessive build-up of these metals in humans through the food chain
A Comparative Study of the Role of Constant and Logistic Recruitment Rates in Epidemiological Models
Get PDFIn this paper, we present three mathematical models of epidemiology. In each of the models, we present a scenario where constant and logistic recruitment rate are incorporated in each case. It was observed in Case I that, the reproduction number of the model with logistic recruitment rate is less than the reproduction number from the model with constant recruitment rate. Further, in Case II, the reproduction number from the model with both constant and logistic recruitment rates are the same. Finally, in Case III, it was observed that the human reproduction number from the model with logistic recruitment rate is higher than the human reproduction number from the model with constant recruitment rate.