Technical efficiency of watermelon (Citrullus lanatus) production in Ogun State, Nigeria

This study was designed to measure the level of technical efficiency, its determinants in watermelon (Citrullus lanatus) production and the constraints in the production system in Yewa North Local Government of Ogun State using a stochastic frontier production function. A combination of purposive and random sampling technique was used to select 80 watermelon farmers for the study. The socio-­‐economic characteristics show that the farmers are predominantly males, mostly (78.8%) married with majority (87.6%) having at least primary school education. The cost and return analysis shows a high net farm income per hectare of ₦25, 574.24. The estimated farm level mean technical efficiency was found to be 65 percent. This result indicates that great opportunities exist for the farmers to increase their productivity and income through improvement in technical efficiency. Age and off-­‐farm income were found to be positively and significantly related to the technical efficiency while education was negatively signed, as expected, but significant. Policies aimed at improving farmers’ access to education through aggressive awareness campaigns and mass mobilizations are recommended by the study

Oxidative Stress, Antioxidant Enzymes and Risk of Hypertension in Obese Type 2 Diabetic Subjects in Osogbo, Osun State, Nigeria

Obesity is a chronic disease often associated with type 2 diabetes mellitus (T2DM) and metabolic syndrome. Coexistence of diabetes and hypertension have adverse clinical outcomes with micro and macrovascular complications. This study investigates the relationship of oxidative stress markers and antioxidants with occurrence of hypertension in obese type 2 diabetic subjects in Osun State, Nigeria. Four hundred and forty-five participants made up of 138 non-obese diabetics, 107 obese diabetic subjects attending two tertiary Hospitals in Osogbo in addition to 100 obese non-diabetes (positive controls) and 100 non-obese non-diabetes (negative controls) were enrolled in this study. FBS (9.55±0.13 mmol/l) and HbA1c (9.51±0.15 %) showed highest significant increase in obese diabetic subjects compared to other groups. Mean serum MDA was highest among obese diabetics (p<0.05) while least values of superoxide dismutase (121.09±3.10 µ/ml) and catalase (24.97±0.66 pg/ml) were recorded in non-obese diabetics (p<0.05). 21.0% of non-obese diabetics (n=29), 54.2% of obese diabetics (n=58), 45.0% of obese non-diabetic (n=45) and 21% of non-obese non-diabetics (n=21) were hypertensive. Age, sex, marital status, religion and occupation (χ2=9.856, 8.405, 22.701, 12.066 and 14.468) respectively were all significantly associated with occurrence of hypertension among obese diabetics.  Receiver operating characteristics (ROC) and area under the curve (AUC) showed MDA having the highest cut off point among obese diabetes subject: 0.529 (0.42-0.64 95% CI) with a steep increase in LDL: 0.505(0.40-0.62 95% CI). This study revealed that increased oxidative stress and reduced antioxidant defense enzymes are strongly associated with dyslipidemia among obese diabetic subject

Development of a System Framework that Estimate Cooling Loads for Air-Conditioning System for Residential and Non-residential Buildings

Cooling Load estimation for air conditioning systems is done either by manual calculation or judgmental estimation based on experience of the air conditioning practitioner. While manual calculation is laborious, estimate based on judgment is liable to error due to gigantic, complex and dynamic nature of present day architectural designs. Load calculation through computer automation is likely to make a positive impact in the dynamic nature of air conditioning applications. This study developed computer software to handle simple and typical load estimate for air conditioning in Nigeria. The study has developed a system framework that estimate cooling loads for air-conditioning system for residential and non-residential buildings. It provides an effective and user-friendly way of introducing a residential cooling load calculation program to users. This software results compare favourably with the previous works and it can be used for educational purposes in air conditioning laboratory. Keywords: Air-conditioning, Cooling loads, Residential buildings, Syste

Assessment of Selected Dams in Kwara State, Nigeria

In Nigeria, more than 50% of the geographical area lies in the Savannah. Over time, this area has been vulnerable to the vagaries of periodic and severe droughts, affecting the survival of man and animals. Safe and economic design and construction of dams to store surplus river waters thus assumed greater urgency. However, dam failures and flood issues has caused catastrophic damages and losses of lives and properties. The uncertainties associated with deteriorating dams have necessitated proper and timely assessment and rehabilitation of these structures. This study identifies and investigates relapse in four (4) selected dams in Kwara State namely: Unilorin-, Malete-, Okuta- Oja- and Asa-dam. A series of field inspection was carried out and results obtained were analyzed. Amongst the four dams, Okuta-Oja dam displayed the worst case of relapse with seepages through the foundation and body of the dam. About 20 baffle blocks out of 30 have been damaged in Unilorin dam, while Malete dam was undergoing re-construction owing to seepage failure. Asa dam however remains intact with no physical and structural defect. Unless appropriately handled, ageing and relapsing infrastructural systems can pose a significant problem, threatening economic prosperity and public safety. Thus, monitoring the state of dam structures to ensure timely maintenance is critically important to preventing catastrophic disasters

Modelling of Moisture Loss and Oil Uptake During Deep-Fat Frying of Plantain (Dodo)

In this study, model was developed to predict moisture loss and oil uptake during deep-fat frying of plantain (dodo). Plantain samples were sliced and fried at different frying temperatures (150, 160, 170, 180 and 190 °C) in a deep fryer for periods varying from 2 to 4 min. Moisture and fat analyses were determined based on the AOAC standard method. Mathematical model was developed from fundamental law of mass diffusion with the aim of predicting moisture loss and oil uptake rate during DFF of dodo. The model was solved numerically using explicit Finite Difference Technique (FDT). Computer codes were written in MATLAB environment for moisture loss and oil uptake in the slices at different frying conditions. The predicted results were compared with experimental data and good agreement was obtained. The correlation coefficients between the predicted and experimental values of moisture and oil transfer models ranged from 0.988 to 0.994 and 0.958 to 0.978, respectively. The results show that the model is consistent and it may be used to predict moisture loss and oil uptake during deep-fat fried of dodo

Investigation of Some Factors Influencing Corrosion on Refrigerator

The corrosion of steel reinforcing bar can proceed out of sight and eventually result in failure of a section of the highway. The collapse of electrical towers, damage to building, leakages in refrigerator all these result in significant repair cost, endangering public safety and health. This paper presents investigation of some factors influencing corrosion on refrigerator, such as presence of dissolved mineral, organic impurities and dissolved gasses in the water. The survey results are presented using graphs. T-test and Anova were used to ascertain the significance of the factors. The result of alternative Hypothesis and null Hypothesis on the T-test and Anova test were carried out on the factors causing corrosion and responsible for the corrosion were able to be identified. The results revealed that the corrosive effect of fresh water varies from locality to locality due to the wide variety of dissolved impurities, the organism causing the greatest corrosion problems are bacteria and fungi, time of exposure to a corrosive environment influences metal corrosion, most salt solution is good electrolyte and can promote corrosive attack and corrosion effects reduce the life span of refrigerator. The result of this research would guide environmental and material engineers in better planning to minimize corrosion

Optimization of Deep-Fat Frying of Plantain Chips (Ipekere) using Response Surface Methodology

Deep-fat frying of plantain chips (ipekere) was investigated with the aim of predicting optimum operating conditions for plantain chips to minimize oil content in order to produce healthy products. The effect of frying temperature and time on moisture content, oil content, breaking force and colour difference of plantain chips was evaluated. Response surface methodology was used to analyze the results of the central composite design of the frying processes for the responses as a result of variation in the levels of frying temperature (150 – 190oC) and frying time (2 – 4 min). Response surface regression analysis shows that responses were significantly (p<0.05) correlated with frying temperature and time. Regression model was developed for the investigation of the effect of frying temperature and time on the responses. The polynomial regression models were validated with statistical tool whose values of coefficients of determination (R2) were 0.995, 0.982, 0.971 and 0.996 for moisture content, oil content, breaking force and colour difference, respectively. The optimum values of moisture content, oil content, breaking force and colour difference were 3.73%, 1.18%, 17.66 N and 65.53, respectively, at frying temperature of 183oC and frying time of 3 min. Therefore, frying conditions had a significant effect on the quality attributes of chips produced from plantain. Keywords: plantain chips, deep-fat frying, regression models, texture and colou

SPATIAL DISTRIBUTION AND HEALTH RISK ASSESSMENT OF HEAVY METALS IN URBAN PARKS AND GARDENS SOILS IN LAGOS STATE, NIGERIA

Distribution and health risk assessment of heavy metals in urban parks and gardens Gani Fawehinmi Park, Ojota, (GFP), Oshodi Heritage Park Oshodi (OHP), Ikorodu/Ipado Garden (IIG), MKO Abiola Gardens, Ojota (MKO), and MOE Garden, Alausa (MOE) soils in Lagos Metropolis, Nigeria were examined using Index of Geo-accumulation (Igeo), Potential Ecological Risk Index (RI) and health risk model. Urban parks and gardens soils were substantially polluted by Cu and Pb due closeness to highways where heavy metals emitted from motor vehicles are deposited.  Geoaccumulation index (Igeo) values for Pb were 10.616, 10.060, 9.027, 8.862 and 8.665 for GFP, OHP, IIG, MKO and MOE respectively. RI values for all the sites showed high pollution as they were all above 200. Health risk assessment revealed that children who visit the urban parks and garden in Lagos State are more exposed to cancer risk from Pb especially through ingestion. Results from this study provided valuable information on the pollution levels of urban parks in Lagos, Nigeria as a result of traffic related emissions and calls for proper monitoring of anthropogenic activities in the metropolis and reduce the human health impacts. The planting of hedge plants and erection of low walls could serve as shield against traffic pollution for the roadside parks     &nbsp

A SURVIVABLE DISTRIBUTED DATABASE AGAINST BYZANTINE FAILURE

Distributed Database Systems have been very useful technologies in making a wide range of information available to users across the World. However, there are now growing security concerns, arising from the use of distributed systems, particularly the ones attached to critical systems. More than ever before, data in distributed databases are more susceptible to attacks, failures or accidents owing to advanced knowledge explosions in network and database technologies. The imperfection of the existing security mechanisms coupled with the heightened and growing concerns for intrusion, attack, compromise or even failure owing to Byzantine failure are also contributing factors. The importance of  survivable distributed databases in the face of byzantine failure, to other emerging technologies is the motivation for this research. Furthermore, It has been observed that most of the existing works on distributed database only dwelled on maintaining data integrity and availability in the face of attack. There exist few on availability or survibability of distributed databases owing to internal factors such as internal sabotage or storage defects. In this paper, an architecture for entrenching survivability of Distributed Databases occasioned by Byzantine failures is proposed. The proposed architecture concept is based on re-creating data on failing database server based on a set  threshold value.The proposed architecture is tested and found to be capable of improving probability of survivability in distributed database where it is implemented to  99.6%  from 99.2%.

Comparative Antioxidants Status of Leaves Extracts of Some Common Antimalarial Plants in West Africa

Objective: Malaria chemotherapy remains relevance and gives way to the re-evaluation of medicinal plants that has already gain approval in the traditional treatments of Malaria. This work evaluated and compared the antioxidant status of methanol leaves extracts of Azadirachta Indica (MAI), Vernonia Amygdalina (MVA) and Carica Papaya (MCP). Methods: Phenols, Flavonoids,percentage inhibition of lipid peroxidation and radical scavenging activities using 1,1-diphenyl-2- picryl hydrazyl (DPPH) and Hydroxyl radicals were determined spectrophotometrically based on international standardized methods . Results: Total Phenolic content in garlic acid equivalence (GAE)were expressed maximally at 700μg/ml by 0.015±0.002, 0.019±0.017, 0.013±0.006 mg/g and flavonoids contents at 350μg/ml by 0.063±0.004, 0.020±0.031, 0.049±0.002 Mg/g quercetin equivalence (QE) for MAI, MVA and MCP respectively. DPPH scavenging activities of 78.60, 55.55 and 54.96 % were obtained at 350μg/ml by MAI, MVA and MCP respectively in the order MAI>MVA>MCP. At 300μg/ml, the extracts scavenged hydroxyl radicals significantly( p≤0.05) by72.00, 77.80 and 53.15 % in the order MVA>MAI>MCP. Intriguingly, extracts also convered significantly (p≤0.05), 50% cell protection as they inhibited lipid peroxidation by50.00, 66.20 and 64.30% in the order MVA>MCP>MAI at 350μg/ml, respectively. Conclusion: Antioxidative properties exhibited by extracts may be correlated with their antimalarial functions, bioactive contents and suggestive of MVA as more potent antimalarial of the evaluated plants which may serve as template for malaria drugs and its local usage encouraged in poverty- stricken malarial-endemic areas of West Africa. Keywords: AzadirachtaIndica, Antimalarial, Antioxidants, CaricaPapaya, Malaria, Vernonia Amygdalina