International Journal of Natural and Applied Sciences

Mathematical analysis of brewery effluent distribution in Ikpoba River in Benin City, Nigeria

2013-03-14T14:36:38+00:00

A fundamental study was carried out in a lotic ecosystem loaded with brewery effluent and other oxygen-demanding wastes from non-point sources to ascertain the pollutant level and its potential hazardousness to aquatic live and human health in the environment studied. Samples of waste water and river water which were taken at predetermined points, on different days, in the neighbourhood of the point source, were subjected to laboratory chemical analysis to determine the concentration of effluent parameters namely: BOD, COD, DO, and pH. Differential calculus and statistical models adapted for the analysis proved to be successful in predicting the contaminant distribution in the river thereby making the research result relevant for surface water pollution control.

Keywords: Brewery effluent, pollutants, lotic ecosystem, water pollution, river, oxygen-sag-curve

Preventive maintenance for computer systems - concepts & issues

2013-03-14T14:36:38+00:00

Performing preventive maintenance activities for the computer is not optional. The computer is a sensitive and delicate device that needs adequate time and attention to make it work properly. In this paper, the concept and issues on how to prolong the life span of the system, that is, the way to make the system last long and function well, with the knowledge of preventive maintenance scheme were elaborated. Good information via document review and research site visits on how
preventive maintenance scheme play a key part to users, details on how maintenance work, the common and effective production and procedures that can be used to maintain the health of one’s computer, the various safety measures that should apply when working with system components
and proper disposal procedures for replaceable components as well as some environment issues that will be useful to computer owners and users were discussed.

Keywords: Computer system, safety measures, disposal procedures, maintenance policy

High power and high external efficiency m-plane Ingan light emitting diodes

2013-03-14T14:36:38+00:00

High power and high efficiency non-polar, m-plane nitride light emitting diodes (LEDs) have been fabricated on low extended defect bulk m-plane GaN substrates. The LEDs were grown by metal organic chemical vapor deposition (MOCVD) using conditions similar to that of c-plane device growth. The output power and external quantum efficiency (EQE) of the packaged 300 x 300 Bm2
was 23.7mW and 38.9%, respectively, at 20 mA. The peak wavelength was 407 nm and <1 nm and a redshift was observed with change in drive current from 1– 20 mA. The EQE showed a minimal drop off at higher currents, where a 90 mA current had an EQE of 35%.

Keywords: GaN substrates, m-plane, LED, diodes, external quantum efficiency

Cytoprotective and healing properties of Musa paradisiacal Linn on gastric ulceration in albino wistar rats

2013-03-14T14:36:38+00:00

This study was designed to investigate the potential preventive and healing effects of the methanolic extract of Musa paradisiacal and its effects in combination with catecholamine on indomethacin-induced peptic ulcer. Forty wistar rats (150 – 250 g) of both sexes were used for the
experiments: 20 rats for prophylaxis and 20 rats for healing assessment. Rats in prophylaxis experiment comprised four groups of five rats each. Group I (Ulcerated control) received distilled water, Groups II - IV received 0.5 ml of the plant extract orally for 14 days. Animals were fasted
for 48 hours after 14 days. 50 mg/kg of both adrenalin (Epinephrine) and dopamine were administered to members of group II and group III respectively. One hour later the animals were sacrificed. Pylorus ligation in the group II, III and IV showed significant (p< 0.05) reduction in the
ulcer index compared to group I. The ulcer index of group I was 14.8±3.5 compared to group II (8.2±1.4), Group III (4.8±1.7), and Group IV (3.0±1.1). The extract also showed 67.57% ulcer protection index. In the healing assessment study, the rats were again divided into five groups of
four rats each. 50 mg/kg of indomethacin was administered orally to the rats after a 48 hours fast to induce ulcer. Group I (ulcerated control) rats were sacrificed one hour after the administration of indomethacin (NSAID) drug and the gastric lesions in the glandular region of the stomach
assessed. Group II (ulcerated untreated control) was administered with normal saline (0.9%), Group III (positive control) was administered with 200 mg/kg of Cimetidine, Groups IV and V were treated with the extract for 14 days while supplying feed and water ad libitum. After the 14 days of
drug treatment, the stomach glandular region was assessed for healing gastric lesions. The ulcer index of the control was 29.5±0.39 and 21±0.85 in the ulcerated untreated control. The percentage ulcer inhibition of Cimetidine was 89.83% with an ulcer index of 3.0±0.46. The extract
at 100 mg/kg produced a significant (p< 0.05) dose dependent healing effect (81.35% inhibition) at a mean ulcer index of 5.5±0.93 and a significant (p< 0.05) mean ulcer index from 29.5±0.39 and 21±0.85 to 2.0±1.15 in group V (93.22%) at 200 mg/kg of the extract. Preliminary
phytochemical screening of the extracts showed the presence of alkaloids, flavonoids, saponins, glycosides, terpenoids, proteins and carbohydrates.

Keywords: Musa paradisiacal, rat, ulceration, cytoprotective, catecholamine, indomethacin

The hypoglycemic effect of aqueous leaf extract of aloes in alloxan-induced diabetic albino rats

2013-03-14T14:36:38+00:00

The hypoglycemic effect of aqueous leaf extract of aloes was studied in alloxan-induced diabetic albino winster rats. Twenty five mature rats used in the study were randomly divided into five groups with five rats in each group. Group C served as the control and received no drug. Group 1
was treated with water; group 2 was treated with the plant extract at 1000 mg/kg; group 3 was treated with the drug glibenclamide (10 mg/kg) and group 4 with a combination therapy (500 mg/kg aloes extract and 5 mg/kg Glibenclamide). The rats were fed ad libitum in 14 day experiment. At 3 days intervals, the blood sample was collected to determine the glucose level in all the different groups. When compared with the standard drug gluburide, the glucose lowering effect of aqueous extract of aloes was significantly at p<0.05. The oral treatment with 1000 mg/kg/day of Aloe extract for 14 consecutive days significantly lowered the fasting blood glucose level (p<0.05) in the diabetic rats indicative of the fact that the extract contains active phytochemicals with potent hypoglycaemic property.

Keywords: Aloes, alloxan, diabetic, glyburide, hypoglycemic effect, albino rat

Does vitamin e supplementation influence serum oestradiol and progesterone concentrations in gilts?

2013-03-14T14:36:38+00:00

Eight mature gilts, randomly selected, individually housed and placed into two groups – vitamin E supplemented and non-supplemented were compared for serum ovarian levels of progesterone and estradiol. This was to access the influence of vitamin E supplementation on the concentrations of progesterone and estradiol using Enzyme Linked Assay. The estradiol concentration was 36.719 pg/mL in the supplemented group, while in the non supplemented group it was 37.344 pg/Ml. Progesterone values were 3.738 (ng/ml) in the supplemented group and 5.313 (ng/ml) in the non
supplemented group. The progesterone values were seen to be on the decline after estrus with a value of 4.425 ng/ml in the supplemented group and 2.250 ng/ml for the non-supplemented animals. The highest values of estradiol was observed during the period of estrus (follicular phase),
while the least values were at the diestrus (luteal) phase. This study is therefore in agreement with the theory of vitamin E's mechanism of action in improving fertility by sparing progesterone.

Keywords: Vitamin E, Enzyme linked assay, progesterone, estradiol, gilts

Analysis of technical and economic efficiencies of Fadama and non-Fadama arable crop farmers in Imo state

2013-03-14T14:36:38+00:00

The study analyzed the technical and economic efficiencies of Fadama and non-Fadama arable crop farmers in Imo state, Nigeria, with focus was on the estimation and comparison of their levels of technical and economic efficiencies. A multi stage sampling technique was employed in the
selection of both the study location and respondents. One hundred and twenty (120) Fadama farmers formed the sample size. Also, 120 non-Fadama farmers were drawn using the same technique for comparison purposes. Data were analyzed using t-test and stochastic frontier model.
Results indicates that the maximum technical efficiency value of Fadama farmers was 87%, while on the part of the non-Fadama farmers, technical efficiency ranged from 0.01 to 0.76 with a mean of 0.50. In terms of economic efficiency, the Fadama farmers posted a mean economic efficiency of 0.52, while their non-Fadama counterparts recorded 0.49. Comparing their efficiency, the coefficient of the difference in technical efficiency is statistically significant. However, the difference in their economic efficiency is not significant. This implies that the Fadama farmers were more technically efficient than economic. The study recommends a reorganization of the ADP extension system to sell the Fadama production technology to more farmers and enhance their productive potentials and capacity.

Keywords: Arable agriculture, Fadama, crop farmers, production technology

Influence of soil and water conservation techniques on yield of small-holder swamp rice farmers in Imo state, Nigeria

2013-03-14T14:36:38+00:00

The study determined the application of soil and water conservation techniques in relation to yield of small-holder swamp rice farmers in Imo State, Nigeria in 2009. Specifically, the socio-economic characteristics of the farmer were described, their influence on the application of the techniques examined and relationship of application of the techniques and yield of farmers ascertained. Purposive and multi-staged random sampling techniques were adopted to select 270 respondents. However, 268 copies of the instrument were retrieved and used for the study. Primary data were
collected through the use of structured questionnaires and interview schedules. The data generated were subjected to both descriptive (frequency, mean and percentage) and inferential (logistic regression, z and t-test) statistical analyses. The study showed that positive significant relationship between gender, education level, yield, access to credit/loan, social participation and application were established, while negative relationship existed between family size, farm size, land tenure and application. This was determined at 5% and 1% levels of significance. Furthermore, a significant positive relationship between yield and application was established at 5% level of significance. The study recommended that small holder swamp rice farmers be motivated through
provision of credit/loan with mild emphasis on collateral.

Keywords: Small holder, farmer, soil, water conservation, swamp, rice

Prevalence of intestinal helminthes among school children and pregnant women in a low socio-economic area, Odenkume-Obowu, south east, Nigeria

2013-03-14T14:36:38+00:00

Between September and October, 2010 a study was conducted to estimate the prevalence of intestinal parasitic infections (IPI) in school children and pregnant women attending the primary health care centers in Odenkume Imo State, Nigeria. Stool samples were collected from 208 children and 62 pregnant women. The stool samples were examined for intestinal parasites by direct microscopy and formol ether concentration techniques. The results indicated that intestinal parasitic infections among school children and pregnant women in the study area were more of helminthes infections (70.7%) than water-borne infections (29.3%). Ascaris lumbricoides, hookworm, Trichuris trichiura and Entamoeba histolytica were the commonest parasites found in stool samples of both study subjects. Age-specific prevalence of the pupils had significant effect on infection (p<0.05). However, there was insignificant difference on infection rate by age of pregnant women (p>0.05). Multigravidae (83.3%) had significantly higher infection rate than primigravidae (52.0%). The burden of parasitic infestations among the school children together with the poor sanitary conditions in the schools should be regarded as an issues of public health priority.

Keywords: Intestinal parasites, helminthes, school children, pregnant women, Nigeria

Seroprevalence of hepatitis B infection among pregnant women in Katsina, Nigeria

2013-03-14T14:36:38+00:00

The seroprevalence of Hepatitis B virus (HBV) in pregnant women attending antenatal clinic at Federal Medical Centre, Katsina was determined within the period, January to March, 2011. Two hundred pregnant women were recruited for this study. Out of this number, 21(10.5%) tested positive for HBV. Of the overall positive cases, 13(61.9%) were in the second trimester, while 7(33.3%) were in the third trimester of their pregnancy. Age brackets 16 - 20 and 21-25 years had 33.3% prevalence rate each, although, there was no significant association (p>0.05) between HBsAg and age groups. This finding implies that the area under study has high endemicity for the infection. Therefore, screening of all pregnant women in the study area for HBsAg is recommended so that positive ones would be give necessary medical care.

Keywords: Seroprevalence, hepatitis B virus, HBsAg, pregnancy, Nigeria

Estimation of bare soil surface temperature from air temperature and soil depth temperature in a tropical station

2013-03-14T14:36:38+00:00

Soil surface temperature has critical influence on climate, agricultural and hydrological activities since it serves as a good indicator of the energy budget of the earth’s surface. Two empirical models for estimating soil surface temperature from air temperature and soil depth temperature were developed. The coefficient of determination (R2) of soil surface temperature from the air temperature model ranged from 0.92 - 0.99, while the mean absolute error (MAE) and root mean squared error (RMSE) ranged from 0.5 - 2.48 and 0.77 - 2.630C respectively. For the soil depth model, the R2 value ranged from 0.75 - 0.96, MAE ranged between 1.05 and 4.94, while RMSE ranged from 1.28 - 5.25. Both models performed well on days of year (DOYs), under similar prevailing weather conditions during the model training period.

Keyword: Air, Soil, temperature, prevailing weather, energy budget, earth surface

Multi- factor volatility of security at Charles Schwab Corporation

2013-03-14T14:36:38+00:00

This paper examined the rate of returns required by investors who invested at Charles Schwab (Discount Brokerage firm) from 30th September, 1987 to 29th August, 1997. The methodology adapted involved the use of a multi-factor stochastic model; APT. The study shows a low systematic risk of the security. There was ARCH effect on the idiosyncratic noise, and about 28.07% benchmark was the opportunity cost of capital that the investment had to beat to a good investment.

Keywords: ARCH effect, rate of returns, low systematic risk, opportunity cost of capital