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Wavelet power spectrum (WPS) techniques were used to evaluate the temporal structure of the clearness index and relative sunshine duration, using monthly values of clearness index and relative sunshine duration between 1995 and 2010. The significant years are featured by high wavelet coefficients of both the clearness index and relative sunshine duration. Low wavelet coefficients noticed during the selected years might emerge from the increase in turbidity and cloudiness, indicating that cloudiness has the greater impact on the solar radiation resulting in weak sky condition. Bootstrap method was also used to acquire regression correlations between clearness index and relative sunshine duration. The correlation coefficient between the monthly values of clearness index and relative sunshine duration for ABK (0.32), ENU (0.31), JOS (0.40), MAID (0.46), OWE (0.25), PH (0.46), SOK (0.65), YOL (0.58). The climatic condition and weather patterns of locations have an impact on the amount solar energy received.

The chaotic behaviour of monthly rainfall data of Benin, Cote d'Ivoire, Cameroon, Ghana, Niger, Nigeria, Senegal and Togo between January 1901 and December 2015 were investigated using wavelet transformation analysis and time series techniques. Wavelet power spectrum was used to split the time series into different scales. Power concentrations between 8 and 16 months were observed for the selected locations. The embedding dimension, delay and largest Lyapunov exponent (LE) were calculated. We observed positive LE ranging from 0.13 to 0.36, indicating the rainfall was chaotic. Ghana had the highest values of LE, while the lowest LE was observed at Niger.. [ABSTRACT FROM AUTHOR]

This paper propose a Pilot Symbol Assisted Modulation (PSAM) channel estimation and compensation technique for rectangular M-QAM based on Cubic interpolation in order to determine the channel state information (CSI) over flat Rayleigh fading channels. The proposed Cubic channel estimator technique is based on sliding window approach and pilot symbol estimates adjustment in order to reduce its computational time complexity. The Cubic estimator is combined with the Koetter and Vardy (KV) Reed-Solomon (RS) decoder to test its performance. The simulation results show that the Cubic interpolation gives the same performance as the Linear, and Sinc interpolators over slow flat Rayleigh fading channel; however, it achieves significant performance improvement of +1.0dB in symbol error rate (SER) over fast flat Rayleigh fading channel. [ABSTRACT FROM AUTHOR]

The annual mean solar indices of MgII core to core wing ratio, solar flux 10.7 cm and sunspot number over an eleven (11) year period, 2000 - 2010, were correlated with the annual mean rainfall, maximum temperature, relative humidity, cloud cover and wind speed of 8 meteorological stations in Nigeria. Correlation analyses were performed to determine relationships between the solar indices and the meteorological parameters at the same temporal scale. In general, weak correlation and significant levels were exhibited between solar indices and meteorological parameters, except Sokoto, Ilorin and Yola, where there were strong negative and positive correlations with high level of significance between solar indices and meteorological parameters. The observations indicated that increased solar activities might have contributed to decrease in rainfall, cloud cover, and relative humidity; but elevated maximum temperature; implying that variability of solar indices affected galactic cosmic radiation reaching the earth's atmosphere. [ABSTRACT FROM AUTHOR]

Multiple regression models have been developed to study the variation of diffuse solar radiation over Nigeria using monthly mean data of clearness index, relative sunshine duration, average temperature and cloud cover. The data for eight stations representing the weather conditions of Nigeria and covering a period 16 years were analyzed, and the statistical accuracy of the regression equations were evaluated by root mean square error, standard error, mean bias error, t-statistic, correlation coefficient and coefficient of determination. The regression produced good correlation between the dependent variable of fraction of diffuse solar radiation and the independent variables of clearness index, relative sunshine duration, cloud cover and average temperature. The multiple regression equations reflected the spatial variability with the latitudes, and can be used for prediction of diffuse solar radiation in Nigeria. A temporal and spatial diffuse solar radiation contour map was developed using Surfer 10 Golden graphic software. [ABSTRACT FROM AUTHOR]

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Diabetes Mellitus (DM) is one of the diseases of public health concerns of the 21st century with rising burden in developing countries. The evaluation of care for diabetes from patients' perspective an important indicator of measuring quality of health services and improving treatment approaches but data of the nature are scarce in Nigeria. The study therefore investigated Patients' Evaluation of the Quality of Diabetes care (PEQD) in Ibadan. This descriptive cross-sectional study recruited 384 diabetic patients from three hospitals where specialised services are offered in Ibadan. A semi-structured pre-tested questionnaire was used to collect data. A 42-point PEQD questionnaire scale was used to collect data and a score of >21 was rated as good Perceived Quality of Care (PQC). Data were analysed using descriptive statistics, chi-square test and logistic regression set at 5% level of statistical significance. Mean age of respondents was 62.5 + 10.8 years and mean diabetes duration was 8.4 + 7.6. Majority (58.3%) of the respondents didn't know the type of diabetes they had. Patients aged less than 60 years were less likely to PQC received as good (OR: 0.21; CI: 0.05 - 0.91) compared to those who were above 60 years. More than half (55.0%) of the respondents perceive quality of care as good. Patients' assessment of the quality of diabetes care received was perceived good. There is need to sustain current satisfactory services in diabetic care and institutionalize periodic survey patients' satisfaction to provide feedback for future quality improvement.

Background: Globally, sexually transmitted disease (STD) is a public health problem. In Nigeria, adolescents form a substantial proportion (22%) of the population and are particularly prone to STDs because of the influence of peer pressure and urge to experiment sexual activity. The study examined the knowledge and attitude of adolescents towards the prevention of sexually transmitted diseases., Method: The survey study was descriptive cross- sectional and carried out among consenting secondary school students aged 10-24 years completing a self- administered questionnaire on knowledge and attitude in relation to sexually transmitted diseases in Ikeji- Arakeji, Oriade Local government, Osun State, Nigeria. The proportionate sampling technique was used to recruit 341 participants into the study. Data were analyzed using descriptive and inferential statistics., Results: Male-Female distributions were 46.3% and 53.7% respectively. Mean age at first sex (sex initiation) was 16.8 years (approximately 17years) and about 97% of the respondents knew about STDs. The media/ magazine was the major source of information about STDs, accounting for more than half (57%) of the responses on sources of STD information followed closely from that from friends with 31%. Parent's source of information was about 11%. Knowledge of STDs centred mainly on HIV/AIDS with 83% and there was a poor knowledge (78%) of its symptoms. About 40% of all respondents had initiated sex at the time of the study and 46% of the adolescents, as against 54%, thought it was bad to initiate sex before marriage. There was a significant association between perception about initiating sex before marriage and ever having sex using bivariate analysis x(2)=268.4, P<0.001). Also, there was a significant difference between the different groups (sources of information) in influencing sex initiation (F=318.47 and P=0.000). Post-hoc analysis showed that each of the different groups (sources of information) was distinct., Conclusion: Adolescents' knowledge of STDs generally limited to HIV/AIDS and perception about sex significantly influenced the decision to initiate sex. There is, therefore, a serious need to implement sexual education and other sexual and reproductive health interventions early for adolescents in Nigeria.