Browsing by Author "Alabi, O."

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    Modification of Darcy's law for turbulent flow in saturated porous media
    (Medwell, 2007) Popoola, O. I.; Adegoke, J. A; Alabi, O.
    "Darcy's law is an essential equation in determining the permeability of porous media which is vital tool in seepage and drainage control in soils. However, whenever the aggregate sizes of the porous media and hydraulic gradient are large, the flow in drains will be semi-turbulent to turbulent. This research aims at modifying the true Darcy's permeability determined under small hydraulic gradients that ensure laminar or nearly laminar flow to allow for reduced efficiency caused by turbulence at greater hydraulic gradient and provide a relation between the maximum gradient for laminar flow and porosity of the porous media. A modeled experiment was set up using sand samples of different porosities from riverbed as porous media, which were packed in a vertical transparent cylinder tube of diameter 1.85x102m and relative permeabilities were determined for gradient ranging from 1.15-15.00. The result of the experiment shows that relative permeability increases with increasing porosity but decreases with increasing gradient. The maximum (or limiting) hydraulic gradient for laminar flow decreases with increasing porosity. Also, the vertical fluid flow in any porous medium is laminar or nearly laminar as much as hydraulic gradient is less than or equal to 1.04. "
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    Schistosome specific antibodies in individuals co-infected with malaria in Southwest Nigeria
    (Nigerian Society of Parasitology, 2012-09) Anumudu, C. I.; Alabi, O.; Oniya, M. O.
    A cross-sectional study design in two primary schools in Ibadan and Akure was used to determine the prevalence of urinary schistosomiasis, and the human humoral immune response to schistosome antigens in individuals with malaria co-infection. Urine samples were collected from 163 children, while 112 gave blood samples. Malaria parasitaemia was determined by microscopy after Giernsa staining and schistosomiasis by centrifugation technique. Serum samples were analyzed for antibodies to crude S. mansoni soluble egg, adult worm antigens, and crude S. haematobium egg antigen by ELISA. The sample population consisted of 40% (62/163) infected with schistosomiasis, 31% (50/163) with malaria, and 6% (10/163) co-infected. All the co-infected students had asymptomatic malaria with parasite densities ranging from 200 - 4,420 parasites/ul blood. IgG titres to the various Schistosoma antigens did not vary significantly. However, antibody titres to the soluble egg antigen increased with age of volunteers. Antigen specific isotype distribution showed a higher prevalence of IgG3 and lgG4.