The impacts of vertical throughflow, rotation, cross-diffusion, and vertical heterogeneous permeability on the double-diffusive convection in a finite rotating vertical porous cylinder have been studied. The fluid in the cylinder is warmed and salted from beneath, and its top and lower walls are taken to be isothermal, isosolutal and permeable. In the model formulation, the Brinkman model was adopted, coupled with the Boussinesq approximation. The normal mode technique is used to perform linear stability analysis and single term Galerkin technique is employed to solve the eigenvalue problem. Further, the influence of vertical heterogeneity, vertical throughflow, thermal and solute Rayleigh, Taylor, and the Soret and Dufour numbers on the fluid system instability has been investigated. We found, among other results, that vertical heterogeneity may either stabilize or destabilize the fluid system. The Dufour number delays both the stationary and oscillatory convection onsets. The positive Soret number is found to have a stabilizing effect on the stationary convection case, with a destabilizing effect on the oscillatory convection case.

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Introduction: A sickle cell anaemia one of a haemoglobinopathy, which constituted as a model for genetically inherited disorders, the course of the disease involves may crises, the investigation of hemostatic components as fibrinogen and fibrinolysis as D-dimer, reflect the overall hemostatic status in the sickle cell anaemia patients. Aim: To investigates hemostatic and fibrinolytic system parameters among sickle cell anaemia patients in the Khartoum state. Methods: The study was conducted in Khartoum state, in JafarIbn Auf Reference Hospital for children as descriptive case-control, a laboratory-based study from 2017-18, specimens were collected randomly of the study population with irrespective to age and gender, blood draw in tri-sodium citrate container, the ethical and consent were obtained. The fibrinogen level was estimated by CA51 semi-automated coagulation analyzer optically based, and the D-dimer were assayed by MISPA-i2, a nephelometric based, the results for each parameter were recorded and using statistical package for the social sciences (SPSS) software for analysis by independent T-test and the statistical significance > 0.05. Results: A hundred participants fifty as study group (HbSS) sickle cell anemic Sudanese child clinically and laboratory-confirmed and fifty healthy as the control group, in comparing a mean of fibrinogen show statistically insignificant (P value 0.645) study group 291.1 ± 107.8 mg/dL and control group 283.4 ± 49.1 mg/dL, but there was a significant difference in comparing a mean of D-dimer in study group 0.56 ± 0.33 μg/mL and control group 0.33 ± 0.14 the P. value 0.00015. Conclusion: The level of D-dimer may be used as a hypercoagulability biomarker in comparison to the level of fibrinogen level for sickle cell anaemia Sudanese child.

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