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Existing models are built upon to develop new ones. As a foundational model in porous media flow, the Darcy flow model has been built upon by many researchers. The groundwater flow equation evolved from the Darcy equation. Dupuit–Forchheimer built upon it to develop the simplified forms for both the confined and unconfined aquifers flow, usable for studying groundwater flow into wells. Aside from height, permeability, and availability of water in the aquifers, other factors influence groundwater flow into wells, as enshrined in the flow equation. This paper investigates the roles of storability, hydraulic conductivity, and source/sink strength in both confined and unconfined groundwater flow into wells using the Dupuit–Forchheimer assumption. In this model, the Dupuit–Forchheimer pressure assumption is substituted into the groundwater flow equations and solved using the Bessel form for separation of variable technique, and Mathematica 11.2 computational software to obtain the expressions for the pressure, which are computed and presented quantitatively. The results show that an increase in the hydraulic conductivity and storability have no effect on the flow pressures in the confined and unconfined aquifers but cause fluctuation in the pressure structure in the unconfined aquifer; the source/sink strength factor causes fluctuation in the pressure structures in both confined and unconfined aquifers flow. However, in both confined/unconfined aquifers the pressures increase as the radii of the wells increase. Importantly, the fluctuation in the pressure structures causes a loss of energy for groundwater flow into the wells.

Venous blood flow through the superior and inferior vena cavae and via a merger to the right atrium of the heart is investigated. Based on the Newtonian assumption for blood, the model is developed using Boussinesq’s approximation for the continuity, momentum, energy, and mass diffusion equations, which are non-linear partial differential equations. The governing equations are non-dimensionalized and solved by the regular perturbation technique. Expressions for the concentration, temperature, and velocity are obtained, analyzed, and presented graphically and quantitatively, and discussed. The results show that an increase in the magnetic field strength and conflux angle produce fluctuations in the flow velocity.

Green plants are the major tappers of the energy from the sun. The collected solar energy in the form of light is used to activate the chemical reaction occurring in matured leaves between carbon dioxide and water, leading to the synthesis of sugar (chemical energy). Two main transport processes are involved in the transport of mineral salt water from the soil through the roots, via the trunk and branches to the leaves where photosynthetic activity occurs, and the translocation of sugar from the leaves to where they are needed and possibly, stored. The xylem vessels bear the absorbed mineral salt water while the phloem vessels bear the manufactured sugar. In this study, neglecting the effects of occlusion and clogging of the phloem channels, we investigate the transport of sugars in the merging phloem vessels using the hydrodynamic approach. The model is designed using the Boussinesq approximation and solved semi-analytically using the regular perturbation series expansion solutions and Mathematica 11.2 computational software. Expressions for the concentration, temperature, and velocity are obtained and presented quantitatively and graphically. The results show among others, that increase in the merging angle causes a reduction in the concentration, temperature, and velocity profiles. However, there exists fluctuations in the concentration and temperature structures.

Evaluation of physicochemical parameters and heavy metal levels in surface water of the Miniokoro stream, Port Harcourt, Nigeria were investigated to determine its potability and pollution status at various stations along the stream. The physicochemical parameters analyzed in the water samples were: pH, Temperature, Salinity, Electrical conductivity, TDS, DO, BOD, Alkalinity, Chloride, NH4+, NO3-, PO43-, SO42- while heavy metals such as Nickel, lead, Iron, Zinc and Chromium were analyzed using atomic absorption spectrophotometer. The results from the research showed an average concentration level of the physicochemical parameters such as pH (5.79-7.01), EC (136.43 - 960.67µS/cm), TDS (90.17 - 1517.67) and the spatial distribution of heavy metals: zinc (0.07 - 1.09mg/l), chromium (0.03 - 0.09mg/l), nickel (0.07 - 0.08mg/l) and iron (12.29 - 39.95mg/l). Water samples from various stations depicts the varying level of pollution along the stream when compared with national and international permissible limit. Thus, it suggests that the government should develop and implement an effective waste management plans due to environmental and other anthropogenic impacts on the stream.

The aim of this study was to evaluate pamidronate for bone pain in a randomised double-blind trial and to evaluate the contribution of new markers of bone resorption in patients with bone metastases.Fifty-two patients with painful bone metastases were randomised to receive a two-hour infusion of pamidronate 120 mg or an identical infusion of saline. Four weeks later, all patients received pamidronate 120 mg. Bone resorption markers measured included urinary calcium (uCa), hydroxyproline (Hyp), and the collagen breakdown products: NTx, Crosslaps and Free Dpd.Symptomatic response during the first four weeks was seen after pamidronate, but not with placebo (P0.05). Quality of life was maintained with pamidronate and deteriorated after placebo (P0.05). Resorption markers did not decrease after placebo, but NTx and Crosslaps both decreased by 70% after pamidronate (P = 0.001). A second infusion of pamidronate did not decrease resorption further, but maintained the suppression of resorption at similar levels for a further four weeks. Symptomatic response to pamidronate correlated closely with the rate of bone resorption; it was more frequent in those patients with an initial NTx value of2 times the upper limit of normal (17 of 27, 62%) and in those where the level of Ntx returned to normal (19 of 32, 59%), than in the patients with either high baseline values of NTx (2 times the upper limit of normal) or Ntx levels which failed to normalise for whom the response frequencies were 2 of 16 (13%) and 0 of 11 (0%), respectively.Subjective benefit after intravenous pamidronate is confirmed in this placebo-controlled study. The new bone resorption markers of collagen breakdown were able to predict clinical response to pamidronate.