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PERCENTAGE ANTIOXIDANT ACTIVITY OF SOME PLANT EXTRACTS IN LINOLEIC ACID PEROXIDATION SYSTEM USING THIOCYANATE METHOD
No full textTotal Antioxidant Activity (TAA) by thiocyanate (-SCN) method was used to assay antioxidant activity of experimental wistar rats treated with oil extracts from kernels of Mangifera indica, (Mi); Irvingia gabonensis, (Ig) and Irvingia wombolu (Iw). All the oil extracts were found to exhibit high antioxidant activity of between 61 – 93% irrespective of time of investigation. The results for percent inhibition of lipid peroxidation of all fractions were found to be significant (p < 0.05) and the order was found to be I. wombolu (93.71±0.57%) in 24hours followed by M. indica (79.17±0.9%) in 36hours and I. gabonensis fraction (92.46±0.53%) in 60hours confirming I. wombolu as a superior radical scavenger compared to the other extract
PRELIMINARY ASSESSMENT OF HEAVY METALS AND WATER QUALITY OF SELECTED WELLS IN TALATA MAFARA, ZAMFARA STATE, NIGERIA
Get PDFContamination of drinking water source by pollutants is one of the major problems affecting rural areas in developing countries like Nigeria. Accessibility of high-quality water is necessary for preventing diseases and improving quality of life. Well water is the main source of drinking water in Talata Mafara, Zamfara State, Nigeria. Well water samples collected from two major locations, Tashar Kali (TKM) and Yarkurna area (YAM) of Talata Mafara metropolis of Zamfara State, Nigeria were assessed for heavy metal concentrationusing atomic absorption spectroscopy (AAS). Also, a physicochemical analysis was carried out using standard procedure of water analysis approved by Association of Analytical Chemist and American Public Health Association. The results obtained revealed that both samples have neutral pH of 6.8, Turbidity of (3.23 and 5.46 NTU), electric conductivity of (29.5 and 29.6μ/cm), Phosphate (0.12 and 0.13mg/L), Temperature (21 and 21OC), TDS (1.5 and 1.7ppt), B.O.D (0.1 and 0.3mg/L), C.O.D (2.397 and 3.196mg/L) and D.O (4.0 and2.0mg/L). The concentrations of heavy metals obtained were Cd 219μg/ml and ND, Cr 0.954 and 0.587μg/ml, Fe 1.948μg/ml and ND, Pb 0.587 and 0.158μg/ml, Mn 0.159 and 0.052μg/ml, Ni 6.620 and 3.104μg/ml, more over Cu, Se, and Zn were not detected in the both samples respectively. the results obtained are compared with the National standard (NSDWQ 2007) and International standard (WHO 2011), The research recommended that the Government should provide some water treatment agencies in the study areas to reduce the level of heavy metals in the water for safety purpose in terms of drinking and domestic use
OPERATING SYSTEM SECURITY AND PENETRATION TESTING
Get PDFPenetration testing is an integral part of any organization or individual that employs the use of Information Technology services. This ensures that their computing infrastructures are checked for vulnerabilities in a routine manner. This paper explains the processes and phases involved in ethical hacking. In addition, major penetration testing types available are also discussed. A Local Area Network (LAN) was designed in a virtual environment running Linux and Windows Operating Systems. We carried out a white box penetration test on the systems. Kali Linux; an open source Debian-based Linux distribution designed for penetration testing and digital forensics was used for the experiment. Several built-in tools in Kali Linux were used, while going through the main phases of penetration testing. Starting from the reconnaissance phase of the process, information about computers was gathered, the network was scanned for vulnerabilities in the scanning phase, and identified vulnerabilities were exploited in the third phase of the penetration test, which is gaining access. Backdoors to exploited system(s) were created to maintain access and event logs were deleted to prevent detection in the final phase of the proces
EFFECT OF BREWERY WASTE-WATERS ON IDEMILI RIVER
No full textThe effect of the waste waters from two Breweries located in Onitsha on the Idemili River was investigated for two years. The physico-and microbiological parameters of both the waste waters and the river samples were also examined. Results obtained indicated that the waste waters had higher level of pH, potassiumions, nitrate ions, sulphate ions and BOD5 than the river sample. Similarly higher values were recorded for outfall sites of river samples than upstream. There was significant difference between the values recorded for the upstream and the outfall site samples of the river at 5% significant level. It was observed that the outfallsite sample was richer in microbial population density than the upstream sample. There were higher levels of both physico-chemical and microbiological parameters of the river samples in the rainy season than in the dry season. The waste water had pollutional effect on the Idemili river especially at the outfall sites
MICROBIAL EXAMINATION OF RAW MILK SOLD IN GARIKI, OKIGWE, IMO STATE, NIGERIA
No full textThis study investigated the microbial quality of raw milk sold in different locations in Gariki, Okigwe, Imo State using standard laboratory techniques. A total of 60 raw milk samples were aseptically collected following standard methods from three different locations to determine total heterotrophic bacteria counts (TBC), total coliforms counts (TCC), and fecal coliforms counts (FCC). The total heterotrophic bacteria counts ranged between 7.2±0.3×103 cfu/ml to 6.9±0.1×102cfu/ml while the total coliform counts ranged from 7.2±0.2×103cfu/ml to 7.0±0.2×102cfu/ml and the total faecal coliform counts ranged between 5.3±0.6×104cfu/ml to 5.1±0.1×104cfu/ml. The bacterial organisms identified and characterized include Staphylococcus aureus, Escherichia coli, Salmonella spp, Pseudomonas aeruginosa, Shigella spp and Enterobacter spp. The percentage distribution of the isolates indicated that E.coli and Salmonella spp had the highest rate of occurrence (100% respectively) while Enterobacter spp had the least occurrence rate (33.3%). There was no significant variation (at P=0.05) in the THBC, TCC and FCC in the samples collected from the different locations. The high level of counts and isolate numbers and types found in the sampled raw cow milk represent a poor keeping quality of milk and public health risk to the consumers. This suggests the need for improved hygienic practice at all levels of milk production in the Gariki communit
DIRECT NUMERICAL METHOD FOR GENERALIZED OPTIMAL CONTROL PROBLEMS CONSTRAINED WITH ORDINARY DIFFERENTIAL EQUATIONS
Get PDFIn this paper, we considered general class of continuous optimal control problem governed by Nth-orderordinary differential equations, in which the state and control variables are and column vectors respectivelywith corresponding matrix coefficients of dimension n×n, n×r. We adopt direct numerical method where the continuous optimal control problem is converted to a nonlinear programming problem via Augmented Langrangian which makes it amenable to optimization techniques (Conjugate Gradient Method). The result is compared with an existing method (exterior penalty method) and found to be more accurat
ON PERFORMANCE OF SOME METHODS OF DETECTING NONLINEARITY IN STATIONARY AND NON-STATIONARY TIME SERIES DATA
Get PDFThere has been growing interest in exploiting potential forecast gains from the nonlinear structure of autoregressive time series. Several models are available to fit nonlinear time series data. However, before investigating specific nonlinear models for time series data, it is desirable to have a test of nonlinearity in the data. And since most of real life data collected are non-stationary, there is need to investigate which of these test is suitable for stationary and non-stationary data. Statistical tests have been proposed in the literature to help analysts to check for the presence of nonlinearities in observed time series, these tests include Keenan and Tsay tests, and they have been used under the assumption that data is stationary. However, in this paper, we investigated the performance of these two tests for the stationary and non-stationary data. The effect of the stationarity and non-stationarity were studied on simulated data based on general class of linear and nonlinear autoregressive structures using R-software. The powers of tests were compared at different sample sizes for the two cases. It was observed that the Tsay F-test performed better than Keenan’s tests with little order ofautoregressive and increase in sample size when data is non-stationary and vice-versa when data is stationary. Finally, we provided illustrative examples by applying the statistical tests to real life datasets and results obtained were desirabl
BACTERIOLOGICAL QUALITY OF SOME FERMENTED FOOD PRODUCTS IN KEFFI, NASARAWA STATE
Get PDFGarri, cassava and yam flours are African traditional fermented food products prepared from cassava and yam that is widely accepted by both rural and urban dwelling peoples with little concern about those microorganisms that are associated with it. The present study was undertaken to investigate the bacteria that are associated with these food flours. Total bacterial count (×105 cfu/g) was found to be highest in cassava (7.1), followed by garri (6.2) and yam (4.4). The total coliform count (×105 cfu/g) recorded 3.7 in cassava, 1.6 in garri, and 1.4 in yam flours. Similarly, total faecal coliform (×105 cfu/g) was highest in cassava flour (4.1), while garri had 2.4, and yam recorded 2.2; also, the Staphylococcus aureus count (×105 cfu/g) was highest in cassava flour (3.6),followed by yam flour (3.1), and garri flour had 2.8. However, the Salmonella/Shigella count (×105 cfu/g) was high in garri flour (3.2), compared to cassava flour (2.5), and yam flour (1.2).The percentage occurrence of the bacteria isolates showed that Staphylococcus aureus was 86.7%, followed by Klebsiella spp. (60.0%), Proteus vulgaris (66.7%), E. coli (86.7%).Similarly, percentage occurrence of Salmonella spp. was 80.0% and Bacillus spp. 66.7%. The bacteria isolated were Staphylococcus aureus, Klebsiella spp., Proteus vulgaris, Salmonella spp., E. coli and Bacillus spp. The isolates were further subjected to antibacterial susceptibility tests usingKirby-Bauer disc diffusion method. The antibiotic susceptibility test revealed that most of the bacterial isolates were resistant to Nitrofurantoin (28%), Septrin (36%), Ampicillin (39%), slightly resistant to Perfloxacin (46%), Nalidixic acid (45%), Tetracycline (46%), slightly susceptible to Augmentin (63%), Ciprofloxacin (67%), Ofloxacin (52%) and highly susceptible to Gentamicin (95%). This present work revealed high bioload and vast array of bacteria in market garri, cassava and yam flours. It is therefore recommended that these food flours be sold in well packaged bags and not as exposed in basins/ bowls. Also, personal hygiene of hawkersand sanitation of utensils are important. Hawkers should be enlightened on hygienic practice
ISOLATION AND IDENTIFICATION OF LIPASE PRODUCING FUNGI FROM THE SOIL ENVIRONMENT OF KEFFI METROPOLIS
Get PDFAn investigation was carried out to isolate, identify and screen for lipase producing fungal species present in the soil environment of Keffi metropolis. Soil samples of approximately 200g each were randomly collected from ten different locations within the Keffi metropolis for the investigation. Sabouraud Dextrose Agar was used for the isolation of the fungal species by pour plate method using Direct Soil Inoculation technique. Five fungal species, Acremonium spp, Mucorsp, Rhizopus stolonifer, Aspergillus niger and Aspergillus flavus were isolated and screened for their ability to produce lipases on tween-20 and phenol red agar. The results of lipase production on tween-20 and phenol red after 5 days of incubation showed that all the isolates were positive for lipase production which was indicated by diameter zone of clearance and visible precipitate of calcium monolaurate due to the deposition of calcium crystal. The diameter of the zone of clearance of the various isolates revealed that Rhizopus stolonifer had the highest lipase producing ability (having a diameter zone of clearance of 12 ± 0.04 mm), followed by Aspergillus niger ( having 10 ± 0.02 mm). Acremonium sp. and Mucor sp. had 8 ± 0.07 mm respectively, while Aspergillus flavus was able to produce just a minimal amount of lipases indicated by its zone of clearance (6 ± 0.04mm). These results demonstrate the presence of lipase producing fungi in the soil environment of Keffi metropolis, Nasarawa State, and these can be explored locally for the production of the enzyme which is of value commercially in the production of detergents, and also as constituents of some special diets and pharmaceuticals
 
DESIGN AND IMPLEMENTATION OF A COMPUTERIZED LIBRARY SYSTEM FOR THE NATIONAL INSTITUTE OF POLICY AND STRATEGIC STUDIES, KURU NIGERIA
Get PDFMost educational institutions in Nigeria, such as the Universities, Polytechnics and Colleges of Education still operate on the manual method of library functions of acquisition, cataloging and circulation. This paper examines the inadequacies involved in the manual method of acquisition, cataloging and circulation functions of a library and proposes a solution by developing a software application to facilitate the automated processing of these library functions. The software was developed using Visual Basic 6.0 and employing MS-ACCESS Relational Database Management System in designing the database. The developed software was tested and found to perform well and produced expected results on completion. With this program, it was possible to record books that were acquired by the National Institute for Policy and Strategic Studies, (NIPSS) as well as the cataloging and the circulation section of the library. The new system has some qualities such as reduction in the cost of processing of information, reduction in time spent in the acquisition, cataloging and circulation of books, increase in accuracy and efficiency, and elimination of duplication of effort which makes it superiorto the manual system of information processing. This new system is flexible and can be modified to suit any kind of library and data processing nee