The effects of thermo-electrically induced convection in alloy solidification

The effects of a constant uniform magnetic field on thermoelectric currents during dendritic solidification were investigated using a 2-dimensional enthalpy based numerical model. Using an approximation of the dendrite growing in free space it was found that the resulting Lorentz force generates a circulating flow influencing the solidification pattern. As the magnetic field strength increases it was found that secondary growth on the clockwise side of the primary arm of the dendrite was encouraged, while the anticlockwise side is suppressed due to a reduction in local free energy. The preferred direction of growth rotated in the clockwise sense under an anti-clockwise flow for both the binary alloy and pure material. The tip velociy is significantly increased compared to growth in stagnant flow. This is due to a small recirculation that follows the tip of the dendrite; bringing in colder liquid and lower concentrations of solute. The recirculation being not normally incident on the tip is most likely the cause for the rotation. Grain growth consisting of multiple seeds with the same anisotropy growing in the same plane, gives a competition to release latent heat resulting in stunted growth. The initial growth for each dendrite is very similar to the single seed cases indicating that dendrites must become before the thermoelectric interactions are significant.

Barriers to effective pain management in sickle cell disease

Sickle cell disease (SCD) is a long-term condition that would benefit from a long-term conditions approach to its care and management. SCD is growing in prevalence, affecting 10,000-12,000 people in the UK, with SCD sufferers having an increased life expectancy from in the past. The most problematic aspect of managing SCD is management of the pain from vaso-occlusive crises. Vaso-occlusive pain is the most common reason for hospital admissions in people with SCD and accounts for large numbers of accident and emergency (A&E) attendances. A literature review was carried out to examine the management of vaso-occlusive pain in SCD. The review identified three main barriers to effective pain management in SCD: the manifestation of vaso-occlusive pain, the sociocultural factors affecting pain assessment, and the concerns regarding addiction and pseudo-addiction. Addressing these barriers will allow people with SCD to have their pain managed more effectively, improve their quality of life and potentially reduce A&E attendances and admissions to hospital.