Natural & Applied Sciences

Natural & Applied Sciences Research Papers/Topics

Geothermal Gradients and Burial History Modelling in Parts of the Eastern Niger Delta, Nigeria

ABSTRACT Reservoir and bottom hole temperatures from seventy wells in the Eastern Niger Delta suggests that two leg dogleg geothermal patterns characterize the geothermal gradients pattern of the Central Swamp and the Coastal Swamp in contrast to the single gradient patterns seen in the Shallow Offshore. In the shallow/continental sections in the Niger Delta, geothermal gradients vary between 10 - 18 o C/Km onshore, increasing to about 24 o C/Km seawards. In the deeper (marine/parallic) secti...

Characterization of Trypanosomes Isolated from Bovine and Canine Using Polymerase Chain Reaction.

ABSTRACT Trypanosomiasis is a vector-borne parasitic disease, transmitted to animals by tsetse fly (Glossina genus) bites. The human type causes sleeping sickness in man while animal type causes nagana in animals. The aim of this study is to characterize trypanosomes isolated from dogs and cattle in Jos South Abattoir. Isolated trypanosomes were subjected to polymerase chain reaction using kin primers targeting internal transcribed spacer 1 (ITS1) of ribosomal deoxyribonucleic acids. The PCR ...

On Equal Predictive Ability and Parallelism of Self-Exciting Threshold Autoregressive Model

Abstract Several authors have developed statistical procedures for testing whether two models are similar. In this work, we not only present the notion of equivalence but also extend this to a measure of predictive ability of a time series following a stationary self-exciting threshold autoregressive (SETAR) process. A proposition and a lemma were used to join the structure of the predictability measure to the coefficients and sample autocorrelation of the SETAR process. Illustrative examples...

Generalized Mathematical Modeling of Aqueous Humour Flow in the Anterior Chamber and Through a Mesh Channel in the Human Eye

ABSTRACT In this work, we propose mathematical models for the processes that take place in the human eye and how they contribute to the development of pathological states. We considered and studied two related dynamics processes that take place in the eye. Firstly, a generalized mathematical model of aqueous humour flow driven by temperature gradient in the anterior chamber is presented. This predicts the flow behavior when the ambient temperature is higher than the core body temperature. The...

Characterisation of the Compounds of the Ethylacetate Extract of the Leaves of Alstonia Boonei De Wild and Their Antioxidant and Antimicrobial Potentials

ABSTRACT Dried and pulverised leaves of A. boonei De Wild (Apocynacea) were extracted using methanol for 48 h. The methanol extract obtained was defatted using n-hexane and fractionated using ethylacetate. The ethyl acetate fraction of the extract was subjected to vacuum liquid chromatography (VLC) in silica gel using gradients of hexane-ethyl acetate. The VLC fractions were further separated on Sephadex LH-20. A total of 10 compounds were successfully isolated and purified using the reverse ...

Course Registration and Result Processing System in Computer Science Department University of Nigeria, Nsukka

ABSTRACT Course Registration and Result processing system form the key activities in the life span of a student. The demand for effective and efficient result computation and output lead to the production of the automated result process. The digitalized process provides the capabilities of centralized repository for storage, management and dissemination of result information to those concerned. A study into the manual process reveals the inefficiencies and the rigorous nature of course regist...

Weak and Strong Convergence of an Iterative Algorithm for Lipschitz Pseudo-Contractive Maps in Hilbert Spaces

ABSTRACT Let H be a real Hilbert space and K a nonempty, closed convex subset of H.Let T : K → K be Lipschitz pseudo-contractive map with a nonempty fixed points set. We introduce a modified Ishikawa iterative algorithm for Lipschitz pseudo-contractive maps and prove that our new iterative algorithm converges strongly to a fixed point of T in real Hilbert space. Contents Certification ii Dedication iii Acknowledgement iv Abstract viii 1 Introduction 1 1.1 General Introduction . . . . . . . ...

Use of Petri Net in Protocol Specification

Abstract This project work is concerned with application of Petri Net in protocol specification. In this project work, definition of Petri Nets and Protocols are given. The role and importance of formal specification techniques are also discussed. Petri Nets are a graphical tool and could be used for the formal description of the flow of activities in complex systems like protocol. It is gaining popularity in recent years as a tool for the representation of complex logical interactions like s...

Hydrogeochemistry and Impact of Iron Ore Mining on groundwater Quality in Itakpe and its Environs, Kogi State, Central Nigeria

ABSTRACT This work is a hydrogeochemical study of groundwater and the impact of over twenty five years of iron ore exploration and mining on groundwater quality in Itakpe and environs. Measurements were carried out on water samples from eight shallow hand dug open wells, four deep boreholes and a seasonal river flowing through the mine area. Groundwater in the area occurs within weathered rocks, fractured and faulted terraces. Depths to water level in the open wells were generally below 15m. ...

Synthesis, Characterization and Solvent Extraction Studies of 3,5-Bis[(2-Hydroxybenzylidene)-Amino]-Benzoic Acid and Its Co(Ii) and Ni(Ii) Complexes

ABSTRACT 3,5-Bis[(2-hydroxy-benzylidene)-amino]-benzoic acid (H2B) and its cobalt(II) and nickel(II) complexes were synthesized and characterized via: electronic, IR, 1 H NMR and 13C NMR. Job’s continuous variation method was used to determine the mole ratio for both metal complexes. Solvent extraction studies were carried out on H2B in 5% DMF with its cobalt(II) and nickel(II) complexes using CHCl3 as organic solvent; with variable condition effects of equilibrium time, buffer pH, mineral ...

Synthesis and Biological Activities of Phenylsulphonylaminoalkanamides

ABSTRACT Palladium catalysed synthesis of substituted 2-[acetyl(phenylsulphonyl)amino]-3- methylbutanamide (176) is reported. The intermediate 2-[acetyl(phenylsulphonyl)amino]-3- methybutanamide (175) was obtained by the reaction between 2-[acetyl (phenylsulphonyl)amino]-3-methybutanoic acid chloride (175) and ammonia. Substituted 2- [acetyl (phenylsulphonyl)amino]-3-methylbutanamides (176a-f) were obtained by coupling 2-[acetyl (phenylsulphonyl)amino]-3-methylbutanamide (175) with various re...

Evaluation of the Antinociceptive and Anxiolytic-Like Activities of Leaf Extract and Fraction of Phyllanthus Muellerianus Kuntze

ABSTRACT The anxiolytic and antinociceptive properties of the leaf extract and fraction of Phyllanthus muellerianus Kuntze (Phyllanthaceae) were investigated.The extract (MME; 500.18 g; 10%w/w), obtained by cold maceration in 1:1 mixture of methylene chloride: methanol for 48 h, was fractionationed in a silica gel column which yielded the ethyl acetate fraction (EF; 199.2 g; 39.83% w/w). The extract and fraction were subjected to phytochemical analysis. Acute toxicity of MME was determined in...

Mathematical Model on Glucose, Insulin and Β-Cells Mass Dynamics in Type 2 Diabetes

ABSTRACT A mathematical model, describing glucose, insulin and β-cells mass dynamics of a type 2 diabetic patient was developed in the form of a system of ordinary differential equation, considering insulin resistance, the body inability to overcome the resistance and the fact that glucose production from food intake is not constant. Numerical solution of the model using RungeKutta code in MATLAB, graphically shows rise in blood glucose concentration and further decline over time in glucose ...

Sonographic Determination of Gestational Age in the Second and Third Trimester from Transverse Cerebellar Diameter Among Pregnant Women in Enugu, Nigeria

ABSTRACT Fetal transverse cerebellar diameter (TCD) was found to be useful in gestational age (GA) assessment during routine fetal ultrasound examination. The aim of this study is to establish normogram of fetal TCD in the second and third trimesters of pregnancy and to compare its ability to predict gestational age with previously published nomograms. Six hundred and ninety seven pregnant women with GA between 14 and 40 weeks were scanned using convenience sampling method. Each woman had thr...

Galactic Cosmic Ray Variability in the High and Mid Latitudes During Solar Cycles 22 and 23

ABSTRACT Galactic cosmic rays are modulated in the heliosphere primarily due to the global merged interaction regions with intense magnetic field which leads to a decrease in the galactic cosmic rays throughout the heliosphere. Using long term averages of solar wind (SW) component parameters in addition to cosmic ray count rates of two high latitude Neutron monitor stations (Apatity and Thule) and two mid latitude stations (Newark and Tbilisi) with different rigidity cut-offs, we analyzed the...


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