No abstract

Rain fall trends all over the world with the attendant socio-economic effects have taken unprecedented dimensions in recent times. Trend studies of this atmospheric parameter will enable us examine the nature of variation and possible causative agents. Both seasonal and long term trends of rain fall in Calabar between 1985 and 2003 have been examined. Monthly and annual rainfall totals, number of rain days and extreme rain fall indices were determined as secondary data and used for the analyses. SPSS statistical package was used to deseasolnalise the data and determine its trend. Both raw data and deseasonalised data were used to examine long term trends and both show some level of increase in rainfall of about 1.9mm and 300mm respectively. The results also show that rainfall has highly pronounced season. The seasonality of all the parameters namely total rainfall, total extreme rainfall, total number of rain days and number of extreme rain days were all similar, with a slight break in the month of August. This break introduces a week or more of drought which is essential for crop production, drying and storage of agricultural products and their by-products .

Background: In this paper, an expanded 10-Dimensional deterministic mathematical dynamic model was formulated that accounted for the role of global stability analysis in the methodological application of dual-bilinear controls with vaccination and impeccable role of adaptive immune response in the control of COVID-19 in Nigeria. In reality, following the introduction of both nonpharmaceutical and pharmacotherapy and the recent availability of vaccines for the control and treatment of the deadly aerosol viral load known as COVID-19, a number of notable scientific investigations on the transmission and treatment dynamics have been conducted but without thoughtful contributions on the combination of these multi-facet control functions that could lead to feasible eradication of the deadly virus. Methods: The model was formulated based expanded 10-Dimensional deterministic dynamic mathematical subpopulations with compartmental interactions investigated using triple-bilinear control functions: bilinear nonpharmaceutical (face-masking and social distancing - , ), bilinear pharmacotherapies (hydroxylchloroquine and azithromycin - , ) and bilinear immunity controls (adaptive immune effectors and BNT162b2 vaccine - , ). Experimental Data was collected from University of Calabar Teaching Hospital from the period July, 2022 through September, 2022, as the initial and final time intervals. Apart from fundamental theory of differential equations explored for system mathematical properties, analytical predictions explored classical method of Lyapunov functions with the incorporation of the theory of Volterra-Lyapunov stable matrices for the analysis of the system global stability conditions. Results: System mass actions and the reproduction numbers for both off-treatment and onset-treatment scenarios was for the first time computed with explicit results obtained ( and ). Moreso, off-treatment scenario showed that population extinction was eminent following the unabated ....