124 research outputs found
Microbial Utilization Of The Hydrocarbon Components Of Atrazine In A Tropical Soil Environment Southwest, Nigeria
Biodegradation of atrazine, a xenobiotic-substance recently introduced into agricultural practice in Nigeria was assessed using native soil microorganisms. Field experiment and laboratory studies confirmed that microbial consortium utilize the hydrocarbon component of atrazine and thereby mineralize the somewhat recalcitrant organic chemical. The atrazine-degraders were isolated on Minimal salt medium and Sabouraud dextrose agar supplemented with atrazine at 0.05g/L and incubated at 28 ±2oC for 72 hrs and 5 days respectively. The sampled agricultural soil was of alkaline pH while the optimum pH at which the microbial consortium metabolizes atrazine was acidic (mean pH 5.63). Total viable count of bacterial atrazine-degraders was 602.5 x 105cfu/ml. Bacterial atrazine-degraders were: Micrococcus sp., Bacillus sp. Enterobacter Sp and Pseudomonas sp. while fungal atrazine-degraders were: Aspergillus fumigatus, A. niger, Penincillium sp and Fusarium sp. Keywords: Agriculture, Atrazine, Biodegradation, Herbicides, Sustainable development, Xenobiotic African Journal of Infectious Diseases Vol. 1 (1) 2007: pp. 25-2
Petroleum-hydrocarbon utilization by native bacterial population from a wastewater canal Southwest Nigeria
The application of a consortium of native bacterial species in bioremediation processes has long been desired in Nigeria because they would be cost effective and efficient in terms of acclimation time. Two Nigerian crude oils (Bonny light and Escravos blend) were exposed to the wastewater canal via oil impregnated membrane filters (0.45 μm diameter) for 21 days in a microcosm experiment. Bacterial petroleum-hydrocarbon utilizers were later harvested from both the millipore membrane filters and laboratory biodegradative studies. Some of the striking discoveries made were that pH fluctuations in the reaction flasks were due to microbial activities, microbial enzymes, presence of crude oil degradation metabolites such as organic acids, surfactants and aldehydes. More petroleumhydrocarbon utilizers were detected at 0 to 15 cm depth than at 15 to30 cm. The petroleum sample with higher fractions of saturated hydrocarbon was biodegraded faster (Bonny light) than the ones with higher fractions of asphaltenes and aromatics (Escravos blend). Escravos blend had C-14 component undegraded after the 3-week oil explosure to the waste water. The physico-chemical properties of the freshwater ecosystem were determined and it supported previous conclusion on the latent self purification capability of the aquatic ecosystem inspite of frequent oil pollution incidents. The mean temperatures of the freshwater ecosystem were within the mesophilic range 27-29°C and the pH of the environment supported acidophilic bacterial consortium. Gas chromatographic profiles of the mineralization process of Bonny light and Escravos blend gave the conclusive evidence for the capability of the native bacterial population to mineralize petroleum hydrocarbons in wastewater, at optimum physico-chemical conditions in the habitat. Petroleum-hydrocarbon utilizers detected included Bacillus megaterium, Pseudomonas putida, Micrococcus luteus, Bacillus brevis, B. punilis and Enterobacter aerogenes.Keywords: Biodegradation, bioremediation, petroleum-hydrocarbo
Relationship between Job Engagement, Security, Training and Employees Workplace Behaviour in Selected Industries in Ogun and Lagos states, Nigeria
A motivated employee cares about his/her workplace and work to contribute towardsthe organizational success, longevity and profitability. There are motivational factors,intrinsic or extrinsic, which influences employees’ workplace behaviour (performanceand level of satisfaction). This study examined the relationship between JobEngagement, Security, Training and Employees Workplace Behaviour in SelectedIndustries in Ogun and Lagos states, Nigeria. The descriptive research design wasused for the study. The population comprised of employees in service andmanufacturing industries in Ogun and Lagos States. A questionnaire tagged “JobEngagement, Security, Training on Employees Workplace Behaviour Questionnaire”was the main instrument used for the research. From the service industries, a randomsampling technique was used to select civil service, the teaching service andmanufacturing firms from both states. A total of 235 respondents were used as samplefor the study. A Cronbach Alpha reliability obtained for each of the sections in thequestionnaire is: Engagement at work (0.74); job security (0.67); training at work(0.80) and workplace behaviour (0.87).Three hypotheses were tested at 0.05 level ofsignificance. Finding showed that there was significant relationship between jobengagement and workplace behaviour of employees (r = .502, n= 235, P < .05), thatthere was significant relationship between job security and workplace behaviour ofemployees(r = .504, n= 235, P < .05). Furthermore, the study revealed that there wassignificant relationship between job training and workplace behaviour of employees (r= .648, n= 235, P < .05). The study therefore recommends that employers shouldassure their employees of their job security, given opportunities for job engagement.Also, employees should be trained to improve their skills and knowledge so as tomake employees care about their workplace and create positive workplace behaviour.Key words: Job engagement, job security, job training, workplace behaviou
Food security status of rural farming households in Iwo, Ayedire and Ayedaade Local Government areas of Osun State, South-Western Nigeria
This research work reports on the food security status of rural farming households in selected Local Government Areas (LGA’s) of Osun State in the South-west Geopolitical zone of Nigeria. The objectives were to estimate extent and magnitude of food insecurity in the study area and determine factors that affect household food security. Three of the thirty LGA’s were selected using stratified random sampling method, based on the geographical location, extent and number of rural population and variations in the socio-economic characteristics of households. The LGA’s were Iwo, Ayedaade and Ayedire. Fifty rural households were then selected from each of the local governments using the random sampling method. One hundred and fifty copies of the questionnaire were administered out of which 103 fully completed and certified responses were used as representative samples for the study area. Food security status of the households was analyzed based on the calorie requirement for all household members. The food security measures applied in this research were Head Count Method, Food Insecurity Gap and Squared Food Insecurity Gap to capture successively more detailed aspects of the food insecurity status of the households. It was found that majority of the rural farming households in the area were food insecure as most of them subsist below the food security line which is 2,280 Kcal in this study. Using the recommended calorie approach, it was discovered that 69.9% of the population were food insecure. In comparison to food insecure households, food secure households have a small family size, earn a high monthly income and make use of modern farm inputs. It is, therefore, advised that food security policy strategies to be put in place by the government should consider the socio-economic characteristics of households in order to achieve more than a marginal reduction in the number of food insecure households.Key words: Households, Rural, Food, Index, Insecurity-ga
Design and Construction of Automatic Fish Feeder using Atmel 8052 Microcontroller
This paper was proposed to design an automatic fish feeder system using Atmel microcontroller application. In a way, it is to control the fish feeding activity by using a fish feeder that combined the mechanical and electrical system to form a device which control the fish feeding activity. This device consists of feed storage, feed stand, display unit, microcontroller and DC motor. The feeds controlled by DC motor which is located under feed storage. A control system was then attached to this device allowing the fish to be fed at preset time as required by user. Hence, promising efficiency and productivity in fish pond in long run. Display unit his is basically the user interface where working of the system is displayed on a screen so that the user have an idea what is going on the system. The message will be displayed on a 16 by 2 liquid crystal display. The controller came with a keypad giving users more option in determining the suitable speed for the motor. In addition, the feed in the automatic fish feeder system will be controlled by the rotation speed of DC motor. Test results at the discharge interval of 4hours and dispensing time of 90minutes within 24hours showed that 15kg of feeds were evenly broadcast across the pond of 12cm less amount of feed lost was recorded compare to manual feeding. The machine adequately manages and preserves feed under harsh conditions
Isolation and characterization of synthetic detergentdegraders from wastewater
The biodegradability of the principal component of synthetic detergent products known as linear alkylbenzene sulphonate (LAS) has been contentious, hence the need to evaluate its primary biodegradation by indigenous microorganisms in wastewater ecosystem. The native microbial consortium of a wastewater ecosystem found to utilize detergent components were characterized using standard and conventional methods. The organisms identified were Enterococcus majodoratus, Klebsiella liquefasciens, Enterobacter liquefasciens, Klebsiella aerogenes, Escherichia coli, Enterobacter agglomerans, Staphylococcus albus, Pseudomonas aeruginosa, Proteus sp., Klebsiella oxytoca, Brevibacterium sp., Myceliophthora thermophila, Geomyces sp., Alternaria alternata, Verticillium alboatrum, Aspergillus flavus, Trichoderma sp. and Aspergillus oryzae. Alkaline pH andmesophilic temperature range (33.9 – 34.3oC) was found to be supportive of the metabolic activities of the detergent-degraders in the tropical wastewater ecosystem. The bacterial detergent-degraders weremore of gram-negative than gram-positive. Fungal detergent-degrader activities were abruptly terminated as the pH shifted to the alkaline range probably due to production of alkaline intermediates.The biodegradation of the synthetic detergent components that occurs in wastewaters, sewage treatment plants and in the ultimate open-water receiving ecosystems is primarily the result of microbial activities
Call hour maxillofacial emergencies presenting to a Nigerian teaching hospital
Objective: The study was undertaken to document the pattern of maxillofacial emergencies presenting to the accident and emergency unit of the Obafemi Awolowo University Teaching hospital, Ile-Ife between January 2001 and December 2002.
Method: The patients' demographics, the time of presentation, duration of emergency and mode of arrival was documented. Injuries of the oro-facial soft and hard tissues, injuries in other parts of the body, the investigations carried out and the management instituted was also recorded.
Results: 106 patients representing 1.3% of all the Accident and Emergency admissions were seen by the maxillofacial unit. Males predominated (90 males against 16 females), mean age was 31.3 years, students (28%) were the most frequently encountered and weekends recorded the highest number of emergencies (50 patients or 47.2%). Trauma was the main reason for presentation (102 patients or 96.2%) and commercial vehicles were the commonest means of transportation to the hospital in 63 patients (59.4%). About a third of the subjects (31 or 36.1%) presented within the first hour, and the soft tissues of the midface were most often involved. The mandible was the most commonly fractured bone (20 patients or 19.6%) and limb injuries were the most commonly observed injury in other parts of the body (43 patients or 42.2%). Sixty-eight out of the 88 patients who required a surgical procedure were treated in the accident and emergency unit and 49 patients (46.2%) were admitted into the wards. The outcome was not significantly affected by the time or mode of presentation.
Conclusions: There is a need for an oral and maxillofacial trauma registry at different locations in the country to ensure a long-term data collection for the development and evaluation of preventive measures.
Key Words: Maxillofacial trauma; emergencies.
African Journal of Oral Health Vol.1(1) 2004: 17-2
Lesions in Broiler Chicks Following Experimental Contamination with Battery Waste
The objective of the present study was to investigate the effect of feed contamination with battery waste on the performance, organs weights as well as the histology of some internal organs of broiler chicks. A total of 120 1- d old broiler chicks were allotted to four dietary treatments in a completely randomized design. The experiment lasted 21 days. The dietary treatments include a control diet with no battery waste (D1). Battery waste was included at 0.5%, 1.0% and 1.5%, in diets 2, 3, and 4, respectively. There were four treatments with three replicates per treatment of 10 birds per replicate. Data collected were used to evaluate feed intake, weight gain, and efficiency of feed utilization. The weights of liver, pancreas, kidney, heart, and lungs were also recorded and tissue samples of each collected for histological examination. Average daily food intake (ADFI), average daily gain (ADG), and feed conversion efficiency (FCE) were not influenced by the dietary treatments (P > 0.05). However, increasing the level of battery waste from 0.5% to 1.5% tended to increase ADFI. Weights of the kidney, liver, gizzard and heart were not influenced by the levels of contamination with battery waste (P > 0.05). Increasing the level of contamination from 0.5% to 1.5% resulted in numerical increases in the weights of the liver, and kidney. The weight of the spleen in chicks fed diets 1, 2, and 3 were similar and was significantly (P<0.05) lower than those fed diet 4. Histological results showed a range in the damage of the kidney and liver of chicks fed different level of inclusion of battery waste, this vary from mild to severe depending on the inclusion level. The kidney had mild to severe congestion of glomeruli and distention of the capillary vessels with numerous thrombi with increasing contamination with battery waste. The liver was characterized by marked coagulative necrosis and degeneration of the hepatocytes and was more pronounced in chicks fed diet 4. The structural alterations were attributed to intake of lead in diets contaminated with battery waste. It was concluded that contamination of feed for broilers chicks beyond 0.5% is detrimental to the performance of broiler chicks
Comparative study on the effect of Thaumatococcus daniellii (Benn) Benth sweetener on the Physicochemical and Sensory Properties of Sorghum based Kunun-zaki Drink
Effect of a natural sweetener (Thaumatococcus danielli) on the physicochemical properties and sensory evaluation of kunun-zaki was determined. Proximate and mineral compositions of the natural sweetener, physicochemical properties and sensory evaluation of kunun-zaki using Thaumatococcus danielli and sucrose were determined. Proximate composition of the aril showed that protein had (33.03%), crude fibre (5.20%), ash content (4.79%), moisture content (12.20%), fat content (0.16%), and carbohydrate (44.17%). The result of mineral obtained for the aril showed the following values potassium (190.00ppm), sodium (167.66ppm), calcium (132.96 ppm), iron (21.59 ppm) and magnesium (14.40 ppm). Physicochemical composition of kunun-zaki varied with concentrations of Thaumatococcus danielli aril and sucrose pH ranged between (3.90-4.90), total solid (4.95-13.49 %) and titatable acidity (0.78-0.39 %) for Thaumatococcus danielli while kunun-zaki sweetened with sucrose had pH (3.51-4.90), total Solids (4.95-7.43%) and titratable acidity (0.74-0.85) respectively. The sensory evaluation showed that the samples sweetened with Thaumatococcus daniel aril compared favorably with sucrose in terms of colour, taste, aroma and overall acceptability. Keywords: Kunun-zaki, Proximate, Mineral, Sensory properties, Thaumatococcus danielli
Triple positivity of HBsAg, anti-HCV antibody, and HIV and their influence on CD4+ lymphocyte levels in the highly HIV infected population of Abeokuta, Nigeria
Background: Few studies exist on hospital-based seroprevalence of triple positivity of HIV/HBV/HCV in Nigeria.Objectives: The study aimed at determining the triple positivity of HIV, HBsAg and HCV among HIV-infected individuals in Abeokuta, Nigeria and defining the influence of these triple infections on CD4+ counts of HIV-infected individuals as antiretroviral therapy improves in Nigeria.Methods: Enumeration of CD4+ levels in 183 HIV-infected persons was done with Partec Flow Cytometer. Seropositivity of HBsAg and anti-HCV antibody was detected with rapid kits.Results: From the result obtained, significance variance (p<0.05) existed between HIV positive persons and persons who tested positive to HIV/HBV/HCV triple infection before and after the commencement of HAART. Of these infections, 31(16.9%) had HBV/HCV/HIV triple infection, while 152(83.1%) had HIV mono infection only, 56(30.6%) had HBV/HIV dual infection only and 43(23.5%) had HCV/HIV dual infection only. Significant variance (p<0.05) also existed between subjects with CD4 counts of <200 cells/μl, 200-499 cells/μl and >500 cells/μl. Highest seroprevalence of HIV (35.0%) was found in age groups 35-44 years and >65 years had the least (2.7%). Significant variance (p<0.05) also existed in the progression of CD4+ lymphocytes cells between subjects with persistent decrease (32.3%) in CD4+ lymphocytes cells and those with fluctuation in their CD4+ lymphocytes cells (12.9%) after the commencement of ART.Conclusion: The study further confirms that triple positivity of HIV/HBV/HCV infection is common in Abeokuta, Nigeria. Testing of these triple infections should be a big concern in the best choice and commencement of ART. Also, the study showed that consistent and prolonged use of HAART had a positive impact on the CD4 count of HIV-infected individuals.Keywords: AIDS, ART, HAART, CD4, HIV/HBV/HC
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