Fast food consumption pattern and body weight status among students of Obafemi Awolowo University, Ile-Ife, Nigeria

The study assessed fast food consumption pattern (FFCP) and body weight status among the undergraduates of Obafemi Awolowo University, Ile-Ife, Nigeria, living in different halls of residence on the university campus during the Rain semester of 2011/2012 session. The study employed survey research design to give an insight into the pattern of fast food consumption and its consequent risk of obesity among undergraduates. The campus has thirteen faculties which have their pivots in science, technology, arts and social science, and nine undergraduate halls of residence. A simple random sampling technique was employed to select 40 students from each hall of nine kinds. The sum total of respondents was 360.The specific objectives were to: investigate the body weight of undergraduates using Body Mass Index (BMI), determine the gender of undergraduates who indulge most in fast food consumption, and examine the influence of fast food consumption pattern on body weight of undergraduates in Obafemi Awolowo University, Ile-Ife. The study relied on primary data which was collected through personally administered questionnaires. The respondents’ weight and height were taken using a weighing scale and meter rule, respectively to determine the Body Mass Index (BMI) which was used to assess students’ body weight status among the respondents. Data collected were summarized and presented using means and percentages. The hypotheses were tested using t-test to determine the significant difference in the Fast Food Consumption Pattern (FFCP) between male and female undergraduates while correlation was employed to test the significant relationship between fast food consumption (FFC) and body weight status. The findings revealed that there was a significant difference (t = 7.14; df = 1; p<0.05) between the FFC of male and female undergraduates. The study further showed from the correlation coefficient analysis that there was a significant relationship between FFC and Obesity (r= 0.47, p<0.05). Based on the findings, the study recommended that the university commission should postulate a compulsory general elective course on physical health and nutrition education across board to give fitness to students and teach them nutrition information and knowledge.Key words: Overweight, Students, Obesity, Fast-food, Food consumption, Binge, BMI, Universit

Performance evaluation of 200W solar photovoltaic panel considering Bauchi microclimatic conditions

Measurement and modeling of broadband and spectral terrestrial solar radiation is important for the evaluation and deployment of solar renewable energy systems. This paper focuses on optimizing the performance of 200W solar module taking into consideration the local climatic conditions of Bauchi locality. The uncertainty in life cycle savings for solar thermal and photovoltaic (PV) systems as linearly correlated with uncertainty in solar resource data. These uncertainties paved way for the need to conduct a critical assessment of the resource. Assessment of the solar resource for these technologies rely upon measured data, where available. In this paper, we present the development of mathematical model of photovoltaic solar cells based on their detailed single diode equivalent circuit representation. Pertinent simulation models for PV solar module both for an ideal weather situation and for taking into consideration the effects of microclimatic conditions that prevail in Bauchi as evaluated and compared with benchmarks available. The complete model of the PV system was implemented using MATLAB/Simulink platform. The standard characteristic curves for the 200W solar panel are as presented. The simulation of the ideal PV system made use of standard test conditions (STC) to facilitate comparison with the existing benchmark results in the literature. The analysis of the characteristics performance curves returned an average VOC = 42.9v and ISC = 4.21A. The simulation results further revealed that the power delivered by the 200W monocrystalline solar module of 144.3W @620W/m2, 35ºC as recorded for Bauchi under all climatic conditions as evaluated. The benchmark values obtained in the laboratory are VOC = 45.5V, ISC = 5.92A and 200-W under the Standard test condition (STC) conditions of cell temperature 25ºC, solar irradiance of 1000W/m2 and air mass (AM) of 1.5. The average conversion efficiency and fill factor as evaluated are 0.77 and 16% respectively. This result agrees with the benchmark of module efficiency of >15.66% recorded at STC. The results conclusively reveal that the microclimate of a locality essentially affects the performances of solar PV systems deployed to each location on the globe. Therefore, utilization of these parameters is essential for consideration in the design of solar systems in all localities

Reactive Power and Voltage Control of the Nigerian Grid System using Micro-Genetic Algorithm

In this paper, a micro-genetic based approach to the optimization of reactive power and voltage profiles improvement and real power loss minimization is presented. The reactive power control devices such as generators, tap positions of on-load tap changer of transformers, shunt reactors are used to correct voltage limits violations while simultaneously reducing the system real power losses. Genetic algorithms (GAs) are well-known global search techniques anchored on the mechanisms of natural selection and genetics. Because of the time intensive nature of the conventional GA, the micro-GA is proposed as a more time efficient alternative. The feasibility and effectiveness of the developed algorithm is tested and verified on the Nigerian grid power system for three case studies scenarios preset in the power world simulator. The far-reaching simulation results that validate the effectiveness of the developed tool are presented and discussed in depth

Antibiotic Resistance and Public Health Perspective of Bacterial Contamination of Nigerian Currency

Nigerian bank notes like other currencies in the world pass through different hands and have been implicated in the carriage of medically important pathogens. This study was undertaken to determine the types of bacteria present on Nigerian currency in Ile-Ife, Osun State, with a view to determining the potential of naira notes as environmental vehicle for the transmission of potential pathogenic bacteria.  Standard microbiological methods were used to isolate, characterize and identify the bacterial isolates from different banknotes. Disc diffusion method was used to determine the sensitivity of the isolates to ten antibiotics. Representative multiple antibiotic resistant isolates were profiled for plasmid deoxyribonucleic acid (DNA). A total of three hundred and five comprising 216 Gram positive and 89 Gram negative bacteria were isolated from two hundred and five bank notes sampled; naira in mint condition was used as control. Thirteen bacterial genera namely Bacillus, Corynebacterium, Staphylococcus, Lactobacillus, Micrococcus, Aeromonas, Citrobacter, Edwardsiella, Klebsiella, Moraxiella, Pseudomonas, Enterobacter and Proteus were recovered. Resistance to antibiotics was generally high and varied among the isolates. Resistance ranged from 18.18% to 100% in Gram negative bacteria and 26.6% to 100% in Gram positive isolates. Enterobacter sp. and Edwardsiella sp. recovered were 100% resistant to all the antibiotics except septrin. All the isolates were resistant to more than one antibiotic. Multiple antibiotic resistant isolates harboured plasmids of various sizes, ranging from 1,356 bp to 17,367 bp in Gram- positive bacteria and 1815 to 23130 bp in Gram negative isolates. Nigerian currency harboured different types of multiple antibiotic resistant bacteria which can be implicated in human infections; hence constituting a potential public health hazard. Keywords: bacteria, multiple antibiotic resistance, currency, plasmids, pathogens, min

Regulatory mutations affecting the synthesis of cellulase in Pseudomonas fluorescens

Pseudomonas fluorescens, was cultured in basal medium containing carboxymethyl-cellulose (CMC) as inducer and glucose or glycerol as carbon and energy sources. Ethylmethanesulphonate (EMS) was used to mutagenize the wild-type organism to produce mutants. The isolated mutants were screened for the isolation of catabolite repression resistant mutants in the presence of 1% (w/v) glucose as carbon source. A total of fifty mutants were isolated. All the mutants produced cellulase in the presence of CMC as an inducer with specific activity of 0.057, 0.088 and 0.074 units/mg protein for the wild-type, catabolite repression resistant mutant4 (CRRmt4) and catabolite repression resistant mutant24 (CRRmt24), respectively. It was observed that addition of glucose or glycerol as carbon and energy sources to the culture medium resulted into considerable reduction in the cellulolytic activity. However, glycerol appeared to be a better carbon and energy source than glucose which inhibited enzyme expression in most of the strains used in this study. It was also observed that potent cellulase production occurred at the exponential growth phase of the organism. The isolated mutants were grouped into three classes based on their induction ratios namely; unimproved mutants, catabolite repression resistant mutants and mutants with highest induction ratio but sensitive to catabolite repression in the presence of high glucose concentration. The overall results obtained showed that cellulolytic activity in P. fluorescens was regulated by catabolite repression.Key words: Pseudomonas fluorescens, ethylmethanesulphonate, mutants, cellulose, catabolite repression, induction ratio.African Journal of Biotechnology Vol. 4 (8), pp. 838-84

Computational Enhancement of Genetic Algorithm Via Control Device Pre-Selection Mechanism for Power System Reactive Power/Voltage Control

In this paper, the application of a novel and computationally enhances genetic algorithm (GA) for solving the reactive power dispatch problem is presented. In order to attain a significant reduction in the computational time of GA, a systematic procedure of reactive power control device pre-selection mechanism is herein proposed to choose a-priori subsets of the available control devices, which maximally influence buses experiencing voltage limit violations. The GA reactive power dispatch module then accesses such judiciously pre-selected control device candidates to determine their optimal settings. A pragmatic scheme aimed at further curtailing the number of the final control actions entertained is also set forth. The far-reaching simulation results obtained for two case study scenarios using the proposed algorithmic procedures on a German utility network of Duisburg, replicated on an operator-training simulator, are presented and fully discussed in depth

Genetic Algorithms Based Economic Dispatch with Application to Coordination of Nigerian Thermal Power Plants

The main focus of this paper is on the application of genetic algorithm (GA) to search for an optimal solution to a realistically formulated economic dispatch (ED) problem. GA is a global search technique based on principles inspired from the genetic and evolution mechanism observed in natural biological systems. A major drawback of the conventional GA (CGA) approach is that it can be time consuming. The micro-GA (µGA) approach has been proposed as a better time efficient alternative for some engineering problems. The effectiveness of CGA and µGA. to solving ED problem is initially verified on an IEEE 3-generating unit, 6-bus test system. Simulation results obtained on this network using CGA and µGA validate their effectiveness when compared with the published results obtained via the classical and the Hopfield neural network approaches. Finally, both GA approaches have been successfully applied to the coordination of the Nigerian 31-bus system fed by four thermal and three hydro generating units. Herein, use has been made of the loss formula developed for the Nigerian system from several power flow studies. For the Nigerian case study, the µGA. is shown to exhibit superior performance than the CGA from both optimal generation allocations and computational time viewpoints

Differential Evolution Approach for Reactive Power Optimization of Nigerian Grid System

The goal of reactive power dispatch is to minimize the system losses and improve the system voltage profiles at all times. This is achieved by adjusting various generating units\u27 excitation systems continuously, discrete tap positions of on-load tap changers of transformers as well as switching of correct doses of inductors or capacitors. This is a mixed integer non-linear optimization problem. In this paper, the differential evolution (DE), a novel evolutionary computation technique which was originally designed for continuous problems is applied to solve this problem. DE appears to ally qualities of established computational intelligence (CI) techniques with a more striking computational performance, thus suggesting the possibility of having the potential for on line applications in the control center; comparison work with other techniques is presently conducted. The developed tool was demonstrated on the Nigerian power system grid for three case scenarios preset on the power world simulator which was linked with DE for power flow calculation (fitness check of solutions). The results achieved revealed that DE procured a significant reduction of real power losses while simultaneously keeping the voltage profiles within the acceptable limits

Comparative Application of Differential Evolution and Particle Swarm Techniques to Reactive Power and Voltage Control

This paper presents the comparative application of two metaheuristic approaches: Differential Evolution (DE) and Particle Swarm Optimization (PSO) to the solution of the reactive power and voltage control problem. Efficient distribution of reactive power in an electric network leads to minimization of the system losses and improvement of the system voltage profile. It can be achieved by varying the excitation of generators or the on-load tap changer positions of transformers as well as by switching of discrete portions of inductors or capacitors etc. This constitutes a typical mixed integer non-linear optimization problem for the solution of which metaheuristic techniques have proven well suited in principle. The feasibility, effectiveness and generic nature of both DE and PSO approaches investigated are exemplarily demonstrated on the Nigerian grid system and the New England power system. Comparisons were made between the two approaches in terms of the solution quality and convergence characteristics. The simulation results revealed that both approaches were able to remove the voltage limit violations, but PSO procured in some instances slightly higher power loss reduction as compared with DE; on the other hand DE required a lower number of function evaluations as compared with PSO. Consideration of computational effort is relevant for potential real time on line application

PERFORMANCE EVALUATION OF 1 kW HORIZONTAL AXIS WIND TURBINE FOR RESIDENTIAL USE IN ABEOKUTA

The conventional energy sources are mainly use in Nigeria to generate electricity and yet, there is a critical challenge of electric power deficit. Therefore, design, modeling and simulation of 1 kW horizontal axis wind turbine as alternative power supply for residential use is considered. This paper presents the design, modeling and simulation of horizontal axis type wind turbine with power output of 1 kW at a wind speed of 4 m/s. Analysis of wind power capacity in W/m2 was done based on the obtained wind data using Weibull probability distribution function. The results showed that the average exploitable wind power density between 4 W/m2 and 14.97 W/m2 was realizable. The wind turbine blades were modeled using blade element momentum theory. The rotational speed of the blades was increased by using airfoil. Mathematical equations were used to determine the tip speed ratio, lift and drag forces and the power output.  The MATLABTM AND SIMULINKTM scientific computer program was used to simulate the model of the wind turbine. The model with its required input parameters, pitch angle, rotational speed of the rotor, angle of attack, and wind speed were varied above and below its actual settings. The results showed that when the parameters were decreased, there was no power output and with the parameters values above the actual settings, the output power was increased to 2.5 kW at a wind speed of 8 m/s and generator speed of 620 rpm. The capacity is small and it is affordable for many household applications in Nigeria