Hepatitis B Precipitating Neurological Complications: A Chronic Inflammatory Demyelinating Polyneuropathy (CIDP) Conundrum.

Hepatitis B virus stands as a prominent contributor to cirrhosis, hepatocellular carcinoma, and other liver-related fatalities. On the other hand, neurological manifestations in HBV-infected individuals are infrequently observed. Chronic inflammatory demyelinating polyneuropathy (CIDP) represents an immune-mediated neuropathy, known for its distinctive pattern of symmetrical involvement and weakness in both proximal and distal muscles. In this study, we present a noteworthy instance of chronic inflammatory demyelinating polyneuropathy (CIDP) occurring in a patient with chronic inactive hepatitis B infection.

Role of solution reconstruction in hypersonic viscous computations using a sharp interface immersed boundary method.

This work discusses the development of a sharp interface immersed boundary (IB) method for viscous compressible flows and its assessment for accurate computations of wall shear and heat fluxes in hypersonic flows. The IB method is implemented in an unstructured Cartesian finite-volume (FV) framework and resolves the geometric interface sharply on the nonconformal mesh through direct imposition of boundary conditions employing a local reconstruction approach. The efficacy of the IB-FV solver is investigated for canonical high-speed viscous flows over a range of Mach numbers. The numerical results indicate that the surface pressure and shear stress distributions are computed with reasonable accuracy, whereas surface heat fluxes for aerodynamically blunt configurations are underpredicted. Employing a set of carefully designed experiments and simple diagnostic tools, we probe the possible causes for the underprediction in heat flux. We show that there exist two sources of error-one due to grid resolution and the other due to solution reconstruction, with the latter being more prominent and responsible for the observed underprediction in heat fluxes. Studies reveal that the heat flux estimates are sensitive to the choice of temperature reconstruction and linear interpolations could lead to poor estimates of heat flux. Our investigations conclusively point out the fact that existing polynomial-based reconstruction approaches for sharp interface IB techniques are not necessarily adequate for heat transfer predictions in high Reynolds number hypersonic flows.

Diffuse-interface immersed-boundary framework for conjugate-heat-transfer problems.

A monolithic solver based on a diffuse-interface immersed-boundary (IB) approach for conjugate-heat-transfer (CHT) problems is presented. The IB strategy assumes that the solid which is "immersed" into the computational grid is occupied by a "virtual" fluid to facilitate construction of "unified" governing equations that are solved everywhere in the domain. A unified momentum equation is devised using the solid volume fraction that reduces to the Navier-Stokes equation outside of the solid and to the no-slip boundary condition inside of it. The "unified" energy equation is constructed in an analogous fashion reducing to a convective-diffusive equation in the fluid domain and a fully diffusive equation in the solid domain with different thermal conductivities (or diffusivities) for both domains. The resulting equations are solved in both domains simultaneously using a hybrid staggered and nonstaggered finite-volume (FV) framework for incompressible flows. The second-order accurate IB-FV solver is employed to carry out investigations for CHT problems in natural and forced convective regimes. Numerical studies for different fluid-to-solid conductivity ratios show that the monolithic IB-CHT solver is a fast, simple, and accurate framework for simulations of CHT problems for Boussinesq flows.