A multi-period Markov model for monthly rainfall in Lagos, Nigeria

Long periods of historical hydrological data such as rainfall and streamflow which are necessary for planning and design of water resources projects, are often not available and have to be forecasted. Many models available for this were developed and tested in developed countries in temperate climates and so their application in tropical climates is questionable. A twelve-period Markov model has been developed for the monthly rainfall data for Lagos, along the coast of South Western Nigeria. The goodness of fit of the model was assessed by estimating the autocorrelations of the residuals of the historical data (from January 1924 to December 1983) for lags one to sixty. A 95% confidence band was also established for the autocorrelations. The results show that all but two of the autocorrelations fall within the 95% confidence band confirming that the residuals are indeed white noise. This indicates that the model is very adequate.Keywords: Markov, multi-perio, rainfall mode

Effect of time of application of spent oil on the growth and performance of maize (Zea mays)

The effect of spent oil pollution on the growth and performance of Zea mays at different stages of growth was investigated in this study. It involved addition of different quantities of spent oil to soils where Zea mays plants at different stages of growth were growing on. The plants showed differential response to quantities of spent oil added to the soils and the times of application. Plants exposed to spent oil pollution one week after germination had the highest level of growth inhibition and the highest chlorophyll content. The leaf area development of the plant was inhibited by the exposure of the plant to spent oil pollution as observed seven weeks after germination. The application of spent oil to the soils three and five weeks, respectively after the germination of the seeds of Z. mays had similar effects on dry matter accumulation of the plant. Statistical differences occur on the growth and performance of the plants exposure to spent oil pollution at different stages of growth (p<0.05, p<0.01 and p<0.001). The results from this study showed that generally Z. mays may suffer greater inhibition of growth and performed poorly when it is exposed to spent oil pollution at tender stage of growth.Key words: Spent oil, time application, growth, performance, Zea mays

Water Withdrawal Trends, Cost and Uses in Ota, Ogun State, Nigeria

Water is an essential component of life. Globally, there is a drawback in its availability and this is increasing and duplicating itself thereby intensifying the struggle for scarce water resources. This study assessed the water resource availability, access, water withdrawal trends, and presents the outcome of a survey of water use pattern in a semi-urban settlement in Southwest Nigeria. The study employed the use of a detailed questionnaire and oral interview for the collection of data. The water use pattern extends to various water consumers such as residential, institutional, commercial and industrial. The collected data were analyzed using descriptive statistics. The results showed that 70% of the settlement depend on groundwater alone, while 30% on surface water. The findings in the study revealed that the rate of patronizing commercial water seller is very high compared to the government approved tariff rate of 66.7% price margin, and there is an increasing demand on water from the various settlements considered. The outcome will enable better investment and management decisions in water withdrawal and usage in the near future as this must be based on estimates of future needs and the available resource potentials

Review of Sustainability in Self Compacting Concrete: the use of waste and mineral additives as supplementary cementitious material and aggregate.

Concrete is one of the commonly used construction materials, but there is a need to develop a new and sustainable technology to make concrete more affordable. With the advancement in technology, concrete was no longer seen as a three entity (binder, aggregate, and water). The unique workability properties of SCC make it unique in the concrete industry. This review assessed the materials, strength, rheological properties of agricultural waste, industrial waste and mineral additives in SCC production. The effect of the utilization of these additives and replacements on structural, mechanical and rheological properties of SCC was espoused. The review revealed that the use of both industrial and agricultural waste enhances the strength properties of SCC. Additionally, the use of agricultural waste improves the rheological properties of fresh concrete. The utilization of expansive material should be discouraged in SCC production. The review revealed that SCC developments ensure a good balance between deformability and stability. It was therefore recommended that SCC should be utilized in pavement construction, particularly when high axle load is expected

Establishing Psychometric Properties of Menopause Symptoms Inventory (MSI)

The literature has suggested that menopause symptoms are conveniently divided into two groups: these are psychological symptoms associated with immediate or eminent cessation of menses, and those physiological symptoms which appear after some years of menopause. The purpose of this study was to construct an inventory based on psychological and physiological symptoms which appear after some years of menopause, to obtain test-retest reliabilities of items and to factor analyze the instrument to empirically investigate the two-type of menopause. The first set of 550 items had mean test-retest reliabilities of 0.76 and yielded two clearly distinct factors in support of the two-type hypotheses. When items with factor loadings less tha