Open Access Original Research Article

Global Stability of Almost Periodic Solution of a Discrete Multispecies Gilpin-Ayala Mutualism System

Hui Zhang

Current Journal of Applied Science and Technology, Page 1-19
DOI: 10.9734/BJAST/2015/19138

This paper discusses a discrete multispecies Gilpin-Ayala mutualism system. We first study the permanence and global attractivity of the system. Assume that the coefficients in the system are almost periodic sequences, we obtain the sufficient conditions for the existence of a unique almost periodic solution which is globally attractive and uniformly asymptotically stable by constructing a suitable Liapunov function, respectively. Two examples together with numerical simulation indicate the feasibility of the main results.

Open Access Original Research Article

Useful Working Fluids for Feasible Super Efficient Trilateral Cycles

Ramon Ferreiro Garcia, Beatriz Ferreiro Sanz

Current Journal of Applied Science and Technology, Page 1-13
DOI: 10.9734/BJAST/2015/19147

This work studies feasible trilateral thermal cycles which undergo controlled isothermal expansion path functions. The interest of the study focuses on choosing some working fluids that exhibit operating characteristics such that, first, fulfil the necessary conditions to yield high thermal efficiency in the supercritical region slightly above the critical point, and second, the critical point of each selected working fluid is located within the range of medium and low temperatures. The relevance of the studied working fluids resides in that the trilateral cycle performance can be increased by using the ability of the selected working fluids to exhibiting very high thermal efficiency when operating within the vicinity of its critical point. Thus, on the basis of thermo physical characteristics such the critical temperature, pressure and maximum allowable operating temperature, working fluids have been selected.

The analysis of the trilateral cycle undergoing the transformation of heat into mechanical work on the basis of an isothermal expansion for every selected working fluid has been carried out. The achieved results reveal that almost all candidate working fluids analysed provides high thermal efficiency when operating in the vicinity of the critical point, considering the two best fluids, water for medium top temperatures, and carbon dioxide for low temperatures.

Open Access Original Research Article

Design and Evaluation of Livestock Dewatering Machine

A. O. Igbozulike, U. D. Bill

Current Journal of Applied Science and Technology, Page 1-6
DOI: 10.9734/BJAST/2015/17858

A livestock dewatering machine was designed, fabricated and evaluated to improve on-farm management of animal waste. This is in response to the need to reduce and eliminate the many challenges of improper waste handling in livestock production farms in Nigeria. The machine consists of a hopper, gear rack, shaft, speed reducer, ball bearings, screen, and discharge chute. The machine is manually operated by cranking of the handle which transmits torque to the shaft and thus set the rack in motion. The rack compresses the slurry against the wall of hard casing, and the liquid is separated from the waste and let out through the screen at the bottom of the casing, leaving the dewatered waste to escape through the discharge chute. Particle size distribution analysis guided the choice of screen size of 2 mm diameter. The machine was tested with pig dung, and it gave a throughput capacity of 472.75 kh/hr and a separating efficiency of 9%.

Open Access Original Research Article

Analysis of Weak and Strong Fiber Bragg Grating

Mohamed B. El-Mashade, A. E. Abdelnaiem, W. S. El-Deeb, N. I. Tawfik

Current Journal of Applied Science and Technology, Page 1-17
DOI: 10.9734/BJAST/2015/18898

Because of the importance of fiber Bragg grating in designing new devices to meet a need range of optical communication systems, it has attracted a great deal of attention. Fiber Bragg gratings have become a key technology in many applications. They are widely used in optical communication systems as a narrow band filters, dispersion compensators, fiber’s sensors and dense wavelength division multiplexing. Advanced functionalities of fiber Bragg grating can be achieved by controlling its structural parameters. This paper is devoted to the modeling and simulation of weak and strong fiber Bragg gratings. The simulation is based on the solution of the coupled mode equations. The effect of the structural parameters such as grating length, refractive index modulation and grating period on the reflectivity, spectral bandwidth and maximum wavelength is studied. Additionally, the role of a new parameter, which is known as fringe visibility, that it can play in controlling the spectral response of the grating is also investigated. The results show that the reflectivity increases by increasing the grating length, refractive index modulation, or fringe visibility and will be decreased by increasing the grating period. Additionally, the influence of the spectral bandwidth and maximum wavelength by the changing of the grating’s parameters is also taken into account in studying the two types of fiber grating.

Open Access Original Research Article

Blending of Acetylated Cassava Starch, Cassava Flour and Wheat Flour for Composite in Bread Making

C. I. Owuamanam, C. C. Ogueke, N. C. Ihediohanma, G. C. Omeire, C. O. Omeni

Current Journal of Applied Science and Technology, Page 1-9
DOI: 10.9734/BJAST/2015/14309

Chemical modification of cassava starch was carried out by acetylation and the resultant modified cassava starch was blended with high quality cassava flour and wheat flour as composites for bread production. High quality cassava flour (HQCF) and cassava starch were produced from TMS 30575 variety. The starch was treated chemically with acetic anhydride. Wheat flour, cassava flour and acetylated cassava starch were blended at varying ratios of 90:7:3, 80:11:9,  70:18:12, 60:25:15, 50:32:18 respectively and 100% wheat flour served as the control. The various composites were subjected to proximate and functional analyses; and thereafter used in bread production, following the straight dough method. The composite breads produced were subjected to physical analysis and sensory evaluation.  The data were analyzed statistical and the means compared at 5% probability. Values obtained from the functional analysis ranged from 1.09-1.99 ml/g; 0.61-0.73 g/ml; 7.90-8.60 ml/g; 7.99-8.60 ml/g and 46.67-51.67°C for the swelling index, bulk density, oil absorption capacity, water absorption capacity and gelling temperature respectively.  The proximate values ranged from 9.5-12.00%; 9.62-11.09% and 68.99-84.45% for protein, moisture content and carbohydrate respectively. Also the bread volume ranged from 725.3–1060.5 cm3. The bread from, 70:18:12 composite did not differ from the 100% wheat flour at p>0.05 in the bread volume. Also, the blend of 70:18:12 did not differ significantly (p>0.05) from the control in the crumb colour, aroma and taste respectively.

Open Access Original Research Article

Alkaline Pretreatment and Fermentation Modifies Protein Fractions and Tannins Content of Karamaka -A High-Tannin Sorghum Cultivar

Nawal M. M. Ali, Abdullahi H. El Tinay, Abd Elmoneim O. Elkhalifa

Current Journal of Applied Science and Technology, Page 1-6
DOI: 10.9734/BJAST/2015/19492

Aims: To study the effect of soaking in 0.20% NaOH for 8 h, followed by fermentation for 16 h on tannins content and protein fractions.

Study Design:  Factorial Experimental design.

Place and Duration of Study: Department of Food Science and Technology, Faculty of Agriculture, University of Khartoum, Sudan and Food Research Center, Shambat, Sudan, between July 2007 and May 2008

Methodology: A high-tannin sorghum (Sorghum bicolor L. Moench) cultivar (Karamaka) was soaked in 0.20% NaOH for 8 h followed by fermentation for 16 h. The effect of soaking and fermentation was studied on tannins content and protein fractions, and untreated sorghum was used as a control.

Results: Results showed that soaking the sorghum grains in NaOH for 8 h caused a decrease in tannins content by 41.96%. Combining soaking and fermentation further lowered the tannins content of sorghum by 59.09%, with a maximum reduction of 81.44%. Soaking in NaOH and fermentation caused a significant (P≤0.05) increase in the albumins fraction by 40.97%, accompanied by a significant reduction in the glutelins fraction by 46.44%.

Conclusion: This modification of sorghum protein fractions along with the decrease in the tannins content can indicate improvement in the quality of sorghum proteins and therefore improve the nutrition status of populations where sorghum is staple food.

Open Access Original Research Article

Morphological Changes in the Testis of Rattus norvegicus Exposed to Cigarette Smoke

José James Lima da Silva-Segundo, Karinne Sousa de Araújo, Jadson Lener Oliveira dos Santos, Marina Bezerra Couto, Jainara Delane Silva Pinheiro, Walter Borges Leal Filho, Ísidra Manoela Sousa Portela Santos, Antônio Luiz Martins Maia Filho

Current Journal of Applied Science and Technology, Page 1-8
DOI: 10.9734/BJAST/2015/18069

Smoking has become a major cause of diseases worldwide. Cigarette smoking is associated with an increase in the development of a number of conditions which represent significant impact on public health. In this light the problem arises: Does exposure to cigarette smoke cause morphological changes in the testicles of rats? The present study is justified because of the growing importance of pathological conditions caused by exposure to substances in the cigarette and the scarcity of literature to correlate exposure to cigarette smoke to the emergence of testicular diseases that can promote infertility. The objective of this study was to analyze the morphology of the rat testicles exposed or not to cigarette smoke by checking the cell area of the germinal epithelium and comparison of histomorphometry of the seminiferous tubules. The study was approved by the “Comitê de Ética em Uso de Animais” (Ethics Committee on Animal Use) - CEUA / FACID under protocol 038/13. A total of 14 animals of the species Rattus norvegicus were selected, males, with 60 days of age and weighing 300 g, divided into two groups (G1 and G2), with seven animals each group. The G1 animals were exposed to smoke produced by the combustion of four cigarettes for 30 minutes, twice a day, six days a week for 60 days. The G2 animals were not exposed. After 60 days, animals in both groups were euthanized and samples of the testicles were dissected and sent for routine processing for further microscopy light analysis. In each testicle sample was randomly calculated the cell area of the germinal epithelium of the seminiferous tubules, with the help of “ImageJ” software. Then the mean areas and standard deviations of each group of animals were calculated, for later histomorphometric comparison between groups. The results were statistically analyzed. Student T test was used, and the level of significance was 5% (p <0.05). Statistical analysis of the data showed that after the exposure period, the average cell area of the seminiferous tubules of the unexposed group is significantly higher than the cell area of the seminiferous tubules of the above group (p <0.05). It can be concluded that exposure of rats to cigarette smoke triggered histomorphometric changes in the testicles, by promoting a reduction of the cell area of the seminiferous tubules, indicating that smoking may result in atrophy of these structures.

Open Access Original Research Article

Assessment of Hydrological Properties and Proximate Impact of Septic Tank Leachate on Well-water Quality in Two Residential Areas in Ibadan, South-western Nigeria

Roseangela I. Nwuba, Amire O. Philips

Current Journal of Applied Science and Technology, Page 1-18
DOI: 10.9734/BJAST/2015/12452

Aims: To determine the impact of leachate from septic tank on proximate well-water quality in two different residential areas and the variation in the physico-chemical parameters of the well-water that are associated with spatial geographical location.

Study Design: Randomized monthly collection and analysis of well-water over four months in two chosen residential areas.

Place and Duration of Study: Residential houses at Agbowo and Akobo, Ibadan, Nigeria between April and August, 2012.

Methodology: The well-water samples were collected from 30 sites once every month; from different wells located at various perimeters from the septic tanks. The distance between the septic tanks and the wells were measured and the water subjected to physico-chemical analysis and bacteriological assessment to evaluate their qualitative, spatial and temporal variations.

Results: A significant increase (p<0.01) was found in results from coliform counts between dry and wet seasons, while significant decrease (p<0.05) was recorded in the concentration of phosphate, salinity, total dissolved solids and potassium. The distance from the well to the septic tanks exhibited a negative correlation with coliform count (p<0.05), as well as for phosphate, nitrate, chlorine and ammonia (p>0.05). The Discriminant Chi square (X2 = 62.526, p<0.01) and Wilk’s Lambda (0.058) revealed a significant discrimination between the two study sites. Partial Eta Squared value of 0.740, 0.382 and 0.137 were reported for location, proximity of septic tank to well-water site and well depth respectively, showing their degree of contribution to variation in parameters measured.

Conclusion: The results stressed the need to set standards concerning the distance and location of wells from septic tanks/septic tank, while considering spatial and temporal variations in hydrological environment of well-water sites.

Open Access Original Research Article

Demolition or Restoration: A Case Study

Nasreddin Elmezaini

Current Journal of Applied Science and Technology, Page 1-10
DOI: 10.9734/BJAST/2015/19513

The decision of whether to repair (restore) or demolish-and-reconstruct a severely damaged building is not always obvious. Such decisions require not only regular inspection and design calculation, but rather long experience and practical judgment that needs to consider safety, serviceability, economy, and local conditions and constraints. In the case of Al-Amin Mosque in Gaza which was severely damaged during the war in July of 2014, two assessments were made. The first assessment classified the building as severely damaged and recommended the total removal of the building and reconstruction. However, another thorough investigation considering previous experience with similar cases and local conditions and constraints concluded the possibility of repairing and restoring the building. A cautious repairing program was successfully adopted which saved time and cost.

Open Access Review Article

Urban Noise Pollution in Nigerian Cities: Imperatives for Abatement

Abotutu Ahi Abel

Current Journal of Applied Science and Technology, Page 1-9
DOI: 10.9734/BJAST/2015/18466

Noise, it is said, is any sound that is unpleasant to the ear. Medically, when it persists, it can damage the ear. Considering the ear organ, it has been said that human ears were designed to process naturally-occurring sounds, and they are beautifully adapted to handle that task. They are able to detect sounds of intensities that vary across many orders of magnitude, and to meaningfully transmit these signals to our brains. But they are not well equipped to deal with the high noise levels that are common in Nigeria’s urban centres today, because such loud sounds occur only rarely in nature. Although the eardrum may sometimes be ruptured by severe noise (acoustic trauma) or pressure changes, the part that is most vulnerable to damage by noise lies more deeply in the inner ear, where the final processing takes place before the sound is converted into nerve impulses that are transmitted to the brain. The extent of damage noise pollution could inflict on man provided the impetus for this study which aims to verify the persistent incidence and magnitude of noise pollution in urban Nigeria. Findings revealed that urban dwellers in Nigeria are exposed to high noise levels (above 70 decibels), with the attendant health implications. The study recommends technical, planning, behavioural and public enlightenment strategies to abate noise pollution in urban Nigeria.