57 research outputs found
Leptin Regulates the Expression of Autophagy-related Genes in Chickens
Autophagy or cellular self-digestion, a lysosomal degradation pathway that is conserved from yeast to human, plays a key role in recycling cellular constituents, including damaged organelles. It also plays a pivotal role in the adaptation of cells to a plethora of distinct stressors including starvation. Autophagy has been extensively studied in mammals and yeast, but little is known in avian species. Thus, the major objective of the present study was to determine the effects of leptin on autophagy-related genes in chicken hypothalamus, muscle and liver. Leptin is an adipocytokine that is mostly produced by white adipose cells in mammals (as fat storage increases), mediating sensing mechanism for fat deposition, signaling the brain via leptin receptor-mediated signal transduction to inhibit feed intake and increase energy expenditure. In the present study, recombinant chicken leptin (625 pmol, 10 µL) diluted in artificial cerebrospinal fluid was injected intracerebroventricularly (ICV) in one week-old Hubbard x Cobb 500 chicks (n=10) and feed intake was recorded at 30, 60 and 180 min after injection. At the end of the experiment, hypothalamii, muscle, and liver were collected for gene expression and protein level analysis. Leptin significantly reduce feed intake after 30 min compared to the control group. ICV administration of both chicken and ovine leptin significantly down-regulated genes (mRNA and protein levels) in hypothalamic and muscle tissues. In the muscle, leptin upregulates the expression of AMPKβ1 and AMPKϒ1, and downregulates the expression of mTOR, upstream regulator of autophagy pathway. Expectedly, there were upregulations of leptin receptors, ObR (
Mathematical model for the control of infectious disease
We proposed a mathematical model of infectious disease dynamics. The model is a system of first order ordinary differential equations. The population is partitioned into three compartments of Susceptible S(t) , Infected I(t) and Recovered R(t). Two equilibria states exist: the disease-free equilibrium which is locally asymptotically stable if Ro < 1 and unstable if Ro > 1. Numerical simulation of the model shows that an increase in vaccination leads to low disease prevalence in a population.Keywords: Infectious Disease, Equilibrium States, Basic Reproduction Numbe
Solution of a deterministic mathematical model of typhoid fever by variational iteration method
The aim of this paper is to apply Variational Iteration Method (VIM) to solve typhoid fever model for a given constant population. This mathematical model is described by nonlinear first order ordinary differential equations. First, we find the solution of this model by using Variational Iteration Method (VIM). In order to show the efficiency of the method we compare the solutions obtained by VIM and RK4. The validity of the VIM in solving the model is established by using the computer in-built classical fourth-order Runge-Kutta method. We illustrated the profiles of the solutions of each of the compartments, from which we speculate that the VIM and RK4 solutions agreed well.Keywords: Typhoid Fever, Variational Iteration Method, Runge-Kutta Metho
Users’ Perception for Quality Service Delivery in Albert Ilesanmi Ilemobode Library, Federal University Of Technology Akure (FUTA)
Abstract
The study investigated Users’ perception for quality service delivery in Albert Ilesanmi Ilemobode Library, Federal University of Technology Akure (FUTA). The descriptive survey research design was adopted for the study; the major instrument for generating data collection was the questionnaires. In carrying out the research, a case study research method was adopted while the researchers made use of random sampling techniques. The Sampling size for this research consists of 10% of registered post graduate students of Albert Ilesanmi Ilemobode Library; hence 200 respondents were selected for the study. However, only 192 respondents completed and returned the questionnaires. The data collected were analyzed using frequency tables, and percentages. The findings of the study showed that the library was used more frequently by students. The perceptions of the quality of library services were found to be satisfactory in the library. The library environment and information resources were considered adequate by Albert Ilesanmi Ilemobode Library users, the most valued aspects of the library were the library collections, and the friendliness and willingness of library staff to assist users. It was also found that users derived a number of benefits from using the library. In the view of above findings the research recommended that the academic library should have a specific guideline for measuring their value. The research work considers the nature of library value and made recommendations for improving library services.
Keywords: Academic libraries; User Satisfaction, Library Services, Service Quality, Valu
Cadmium Increases the Sensitivity of Adolescent FemaleMice to Nicotine-Related Behavioral Deficits
This study investigates spatial and nonspatial working memory, anxiety related behavior, and motor activities in cadmium and/ornicotine exposed female adolescent mice. P28 female adolescent mice (albino strain) were divided into four groups of five
NUMERICAL SOLUTION OF VOLTERRA INTEGRO-DIFFERENTIAL EQUATIONS BY AKBARI-GANJI’S METHOD
In this study, Akbari-Ganji’s Method (AGM) was applied to solve Volterra Integro-Differential Difference Equations (VIDDE) using Legendre polynomials as basis functions. Here, a trial solution function of unknown constants that conform with the differential equations together with the initial conditions were assumed and substituted into the equations under consideration. The unknown coefficients are solved for using the new proposed approach, AGM which principally involves the application of the boundary conditions on successive derivatives and integrals of the problem to obtain a system of equations. The system of equation is solved using any appropriate computer software, Maple 18. Some examples were solved and the results compared to the exact solutions
Investigation of Distribution System Stability with Incorporation of Capacitor Switching: A Case Study of Monatan 11 Kv Distribution System
Effectiveness of an electrical distribution system depends on the stability of its voltage profile. Several methods such as Static Compensator (SC), Thyristor Controlled Series Compensation (TCSC) and Series Capacitor have been applied for the stability of the system. However, these methods have been characterized by harmonic variation and low efficiency. Therefore, this research paper applied Shunt Switching Capacitor (SSC) on 11 kV distribution system located at Monatan, Ibadan, Oyo State in order to investigate the stability of the system during outages. Hourly data on bus voltage of the system were collected to determine the average bus voltage and voltage drop of the distribution system for stability evaluation using IEEE statutory limits method. Load Flow Model (LFM) of the distribution system was developed with incorporation of Capacitor Switching Compensation (CSC). This was solved using Kirchoff’s Current Law( KCL) analysis to improve the average bus voltage and voltage drop of the distribution system while simulation was done using MATLAB R2015a. The results of the average bus voltage and voltage drop of the distribution system were 10.5  and 4.2 , respectively. The CSC model improved the average bus voltage and voltage drop by 6 % and 33 % respectively. The research showed that incorporating capacitor switching as a compensation technique enhanced the stability of the distribution systems. The research is useful in the planning and optimization of electrical distribution systems. Keywords: Electrical Distribution System, Voltage, Capacitor Switching Compensation, Load Flow Models, Monatan 11 kV Distribution System, Voltage Drop, MATLAB. DOI: 10.7176/NCS/14-02 Publication date:August 31st 202
SERIES SOLUTION OF TYPHOID FEVER MODEL USING DIFFERENTIAL TRANSFORM METHOD
This paper presents an analysis of PSIuIeTR type model, which are used to study the transmission dynamics of typhoid fever diseases in a population. Basic idea of typhoid fever disease transmission using compartmental modeling is discussed. Differential Transformation Method (DTM) is discussed in detail, which is used to compute the series solution of the non-linear system of differential equation governing the model equations. The validity of the (DTM) in solving the proposed model is established by classical fourth-order Runge-Kutta method which is implemented in Maple 18. Graphical results confirm that (DTM) is in good agreement with RK-4 and this produced correctly same behaviour of the model, thus validating the efficiency and accuracy of (DTM) in finding the series solution of an epidemic model
Development and modelling of oil-palm-mesocarp fibre polyester resin composite for helical gears
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