Evaluating the Strength Characteristics of Clay- Gravel Mixtures

Shear strength is one of the most important soil properties in almost all geotechnical engineering problems. Therefore, this study was aimed at investigating the effect of gravel on the shear strength of clayey soil. Two clayey soil samples were obtained from a dug pit from different locations in Osogbo, Osun State and the gravels were collected locally. Three different gradations of gravel (2-6mm, 6-12mm, and 12-20 mm) were mixed in a dry state in percentages of 5, 10, 15, 20, 30, 40 and 50% with the collected clay soil respectively. Initially, some physical properties of clayey soil and the gravel, which include specific gravity, particle size analysis, liquid limit and plastic limit, were determined in accordance with BS 1377-3:2018. Consequently, the California Bearing Ratio (CBR) and Consolidated - Undrained (CU) triaxial compression tests at three different confining pressures of 50, 100 and 150 kN/m2, with a loading rate of 0.5 mm/min were carried out on the clay-gravel mixtures in accordance with BS 1377 (1990). The results from the CBR test indicated that the CBR value of the clay-gravel mixtures was higher than that of pure clay. The result of shear strength showed that the cohesion and effective angle of internal friction increases as the concentration of gravel increases from 0 to 50%. As the gravel size was increased from 6-12mm, effective cohesion reduces and angle of internal friction increases.  It concluded that locally available gravel can be used to improve the strength properties of clayey soil for engineering construction

Impact of Credit Demand on the Productivity of Rice Farmers in South West Nigeria

Employing cross-sectional data from 360 rice farmers selected from three states in South West Nigeria, the study analyzes the impact of credit demand on the productivity of rice farmers. An Endogenous Switching Regression Model (ESRM) that accounts for both heterogeneity and sample selection biases were used to estimate the impact of credit demand on rice productivity in South West Nigeria. In addition, a Tobit regression model was employed to measure the level of participation of rice farmers in the credit market. The result of the first stage (probit model) of the ESRM revealed that household assets, access to service, climate variables, regional variables, and transaction cost are statistically significant in influencing farmers’ credit demand decision. The results of the second stage of the ESRM indicate factors such as household assets and access to service were statistically significant in explaining variations in rice productivity among participants and non-participants in the credit market. Furthermore, the results of the Tobit model showed that the farmers’ location income from rice farming experience, interest rate, and distance to the source of credit are statistically significant determinants of the amount of credit received. These findings suggest that facilitating farmers’ access to credit will improve rice productivity. Therefore, it is imperative for government and development partner to work together in order to improve the conditions for suitable agricultural credit access to rice farmers, especially a review of interest rates. A necessary addition should be developed to the assistance already being provided under Nigeria Incentive-Based Risk Sharing System for Agricultural Lending (NIRSAL) in the form of loan guarantees and other risk-sharing incentives, such as a regulatory environment that supports the modern contractual obligations that are characteristic of well-functioning agricultural financing. This would not only contribute to the intensification of rice production in Nigeria to meet its increasing rice demand, but also improve rice farmers’ productivity and their households’ incomes

Analysis of Independence of Available Infrastructure on Geographical Location of Public Secondary Schools in Ondo State, Nigeria

This paper has attempted to study the availability of infrastructural facilities in public secondary schools in Ondo State, Nigeria. Six local government areas (LGAs) were randomly selected with due consideration to the geo-political set-up of the State. Quantitative methods of analysis that were used include both descriptive and inferential statistics. The descriptive statistical techniques were tabular presentation and bar chart while the inferential statistical technique applied is chi-square analysis. The inferential statistics revealed that enrollment of students in secondary schools depends on gender and on Local Government Area. Also, the level of equipping of laboratories, availability of information technology facilities,  portable water supply and supply of electricity depend on Local Government Area while availability of library in secondary schools is independent of Local Government Area. Conclusively, much still need to be done in the area of infrastructural development in public primary and secondary schools in Ondo State towards the achievement of the vision 20: 2020 goal of Nigeria as one of the 20 most developed economy of the world in terms of education. Keywords:  education, infrastructure, information technology, chi-square, enrollment

ASSESSMENT OF JEBBA HYDROPOWER DAM OPERATION FOR IMPROVED ENERGY PRODUCTION AND FLOOD MANAGEMENT

One of the reservoir management options for flood moderation and energy production is the operation of Hydropower Dams to protect people and their socio-economic activities in flood plain areas. This study focuses on assessing Jebba Hydropower Dam Operation for improved energy production and flood management. Available Data for 27-year period (1984 - 2011) such as inflow, elevation, turbine release, generating head, energy generation, tailrace water level and plant coefficient was obtained from Jebba Dam Station. The present reservoir-operating rule was investigated using statistical analysis to model the operation of the multi-purpose reservoir. Statistical tests carried out in accordance with standard procedure include chi-square (χ2), probability plot coefficient of correlation (r), and coefficient of determination (R2). The results show that the optimal solution at operating performance of 50% reservoir inflow reliability has the total annual energy generation of 42105.63MWH with adequate water supply for downstream users and for irrigation throughout the year with annual optimal evaporation losses averaged at 58.16Mm3. Average optimal energy generation obtained is 19% of the observed energy generation but with adequate water supply for downstream users and for irrigation throughout the year. It is, therefore, essential to develop a decision-making framework capable of handling the conflicting demand

EFFLUX MEDIATED MULTIDRUG RESISTANT PSEUDOMONAS AERUGINOSA ISOLATED FROM DIFFERENT ENVIRONMENTAL SOURCES

Pseudomonas aeruginosa is an important opportunistic pathogen and one of the leading causes of multi-drug resistant nosocomial infections. This study was therefore carried out to determine the resistance nature, and the role of efflux pump in multidrug resistance of Pseudomonas aeruginosa isolated from different environmental sources using the efflux pump inhibitor, Carbonyl Cyanide 3-Chlorophenylhydrazone (CCCP). A total of 220 environmental samples were collected and processed following standard techniques. Susceptibility to antibiotics was performed using disc diffusion methods as described by the Clinical and Laboratory Standards Institute. Activity of the efflux pump system was carried out using the efflux pump inhibitor, CCCP. Results obtained identified 100 (45.5%) Pseudomonas aeruginosa and 72 (32.7%) other strains of Pseudomonas spp. The susceptibility testing revealed that all the identified strains of Pseudomonas aeruginosa that were subjected to susceptibility test were significantly resistant to ampicillin and cefotaxime, But the  resistance profile of isolates to tetracycline, chloramphenicol, ceftriaxone, cefuroxime and perfloxacin were 93%, 72.1%, 79.1%, 58.1% and 51.2% respectively. However, imipenem was the most sensitive (100%), followed by cefepime (65%) and gentamicin (44%). Carbonyl Cyanide 3-Chlorophenylhydrazone decreased the minimum inhibitory concentration (MIC) of the isolates by 2 folds. Results obtained have shown the ubiquitous presence of multi-drug resistant P. aeruginosa from the environmental samples examined. Furthermore, it indicated the role of efflux pump in antibiotics resistance in P. aeruginosa isolates which indicate that P. aeruginosa strains from environmental sources could resist antibiotics by the efflux mechanism.     &nbsp

Vulnerability analysis of maize farmers to climate risk in Kwara state, Nigeria

There is an increasing concern on the vulnerability of farmers to the impact of climate change. The study analyses maize farmers’ vulnerability to climate risk, it specifically determines their knowledge of climate change; examines their vulnerability; identifies the determinants of vulnerability and their management strategies. Three-stage random sampling was employed. Descriptive statistics, Likert scale, vulnerability index and stepwise regression were the tools of analysis. Result showed 79.5% of the respondents were males while 20.5% were females; 77.5% had no formal education; and their mean farm size was 2.88ha. The majority of the farmers agreed that the climate is changing which is corroborated by the meteorological data analysed. The vulnerability assessment shows that the farmers are vulnerable. The determinants of vulnerability among the farmers were years of experience, information about climate change, sensitivity of farming resource and susceptibility to drought.. The results also showed that farmers do not have the necessary capacity to mitigate against the effect of climate change. It therefore recommends that adequate climatic information, easy access to drought tolerant maize variety should be prioritize in policy making.Keywords: Climate Risk, Kwara State, Maize Farmers, Nigeria, Vulnerability

The burden of erectile dysfunction in hypertensive men attending a general out patient unit in a rural Nigerian hospital

Background: Hypertension is often cited as a cause of erectile dysfuntion (ED) which is currently known to be a risk factor for coronary artery disease (CAD). Both ED and CAD lower the quality of life of affected men.Objectives: To study the characteristics of men with hypertension-associated ED and to determine the ED burden in hypertension in this rural community.Design: Questionnaire based cohort study.Setting: The General Out Patient unit of Irrua Teaching Hospital, Nigeria.Subjects: Men attending the General Out Patient Unit during the study period for diagnosis and treatment of hypertension and who consented to the study.Outcome Measure: The burden of ED in hypertensive men and the characteristics of such men.Result: Two hundred and forty two respondents correctly filled and submitted the questionnaire. Fifty four (22.41%) were newly diagnosed, un treated while 188(77.59%) had been on treatment. In the untreated group, 40(74.07%) and in the treated group, 166(86.20%) had some degree of ED compared to 57.4% in the general population. Age(p=0.000), BMI(P=0.010)in the newly diagnosed group and age(p=0.001), duration of treatment(p=0.009) and co-morbidities(p=0.010) in the treated group were risk factors for ED. Majority of the men(80.30%) were on combination therapy.Conclusion: ED is common among hypertensive men, treated or untreated. Considering the socio-economic and clinical effects of CAD for which ED is a fore runner, physicians should endeavour to obtain a sexual history when evaluating these men as a preventive measure against feature cardiovascular event

Abundance and Distribution of Large Mammals in the Upper Ogun Game Reserve, Oyo State, Nigeria

Three different methods for estimating wild animal populations were used to assess the density of different species in a game reserve in the Sahel region of Nigeria. Hunting for bushmeat by local communities living around the reserve was identified as one of the threats to wildlife populations. Bushmeat was an essential resource for communities around the reserve

Abundance and Distribution of Large Mammals in the Upper Ogun Game Reserve, Oyo State, Nigeria

In this study, three indirect methods [counts of animal droppings, footprints, and tracks) were used as indices to estimate the abundance and distribution of large mammals in the Upper Ogun Game Reserve, which is located in a typical Southern Guinea savanna zone of Nigeria. Thirteen animal species were recorded; kob, bushbuck, hartebeest, roan antelope and duicker were the most abundant. The distribution of large mammals appears to be controlled by several factors: accessibility to the River Ogun [the main source of water in the reserve), availability of food and cover, and the extent of illegal hunting. An analysis of questionnaires distributed to various people living in villages around the reserve revealed that these people depend heavily on bushmeat for their animal protein requirements. They also use other wildlife products to meet their economic, social, and cultural needs. It is recommended that adequate protection should be accorded to the game reserve for at least 5 years. After that time, the area could be opened up to tourism, and controlled hunting could be permitted in the buffer zone around the reserve

Two case reports on Mandibular metastases

Metastatic tumours of the oral cavity are not common. The most common site for bone metastases in the head and neck region is the mandible. Metastatic lesion of the mandible most commonly originate from the lungs in men and breast in women, and these lesions (or tumours) usually are carcinomas rather than sarcomas. We report two cases of metastatic lesions in the mandible: (1) A 19year old male with right mandibular swelling and a nodular swelling in the distal two–third of the right tibia. Radiograghs revealed sclerotic lesion with a sunburst appearance in both the jaw and tibia. Histology of the jaw lesion confirmed a metastatic osteosarcoma of the mandible. (2) A 51year old female with a right mandibular swelling with associated swelling in the anterior neck, right shoulder and right parietal region of the skull. Computerised tomography scan (CT) of the jaws showed an osteolytic lesion of the right mandible. CT scan of the brain also showed a large lytic lesion seen in the posterior aspect of the right parietal bone. Histology of the jaw mass confirmed a metastatic follicular carcinoma from the thyroid. Mandibular metastasis may be the first presenting feature of underlying occult malignancy of another primary site. Therefore, clinicians should maintain a high level of suspicion while evaluating patients with a history of cancer presenting with oral lesions. Keywords: metastatic tumours, mandible, tibia, thyroi