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Objective: Multiple lines of evidence support the key role of neuroinflammation in the pathogenesis of epilepsy and associated comorbidities. The main aim of this investigation was to study the role of different inflammatory pathways in human epileptogenesis Methods: Using immunohistochemistry [for full text, please go to the a.m. URL]

Effective shearing of fine powders for surface modification and dry coating requires a compressed powder bed to prevent aeration. A device known as Mechanofusion® provides the necessary conditions using a centrifugal field, under which submicron particles are coated onto coarser host particles by shearing under great compressive forces at very high strain rates. This creates composite powders with enhanced properties, such as good flowability, surface functional effects, etc. Understanding the dynamics of particle motion, required level of shear stresses and input energy is a prerequisite for process optimisation. Here, numerical simulation by the Discrete Element Method is carried out, analysing features which are otherwise difficult to obtain by experimental work, e.g. the determination of the thickness of the zone in which particles experience shearing strains, as necessary for functional effect, compressive forces on particles, and input energy. Correlations are proposed for the energy input requirement and stresses experienced by the device as a function of rotational speed.

Large contact forces on granules could give rise to undesirable attrition. In a new device, referred to as the Particle Shear and Impact tester, granules are subjected to repeated and sequential impact and shearing, the latter effected by two counter-rotating rollers with differential angular speeds and an adjustable gap between the rollers. This enables the contact force distribution to be varied in order to apply representative contact forces, as experienced in manufacturing plants. Granule flow in the rollers is simulated by Distinct Element Method for several roller gap sizes. The resulting contact force distribution is compared to that from shear cell simulations for representative plant normal stresses (8 to 15 kPa), in order to calibrate the appropriate gap size. The 90th percentile of the contact forces distributions from the two simulations are matched to set the gap size. A roller gap size approximately 3.5 times the 90th percentile of the particle size (based on number distribution) gives a good match of the interparticle contact forces between the rollers and the shear cell. This enables replicating the stresses that granules experience in plants, whether during handling and transport, or during more severe stressing conditions, e.g. compaction or even grinding, thereby assessing attrition or fragmentation propensity of granules.

Objective: Microglia, mono-nuclear cells distributed throughout the CNS, are key immune effector cells of the brain. The complex interactions between microglia and the other cell types in glioma play a crucial role in the development of novel treatments, presumably via the regulation of tumor progression[for full text, please go to the a.m. URL], 72. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie (DGNC), Joint Meeting mit der Polnischen Gesellschaft für Neurochirurgie

Triboelectric charging can strongly influence bulk powder flow behaviour, and hence its characterization is of great interest for safe manufacturing operations. In a recent development, the use of an aerodynamic disperser, employing a pressure pulse to disperse a small powder quantity, shows a great potential for inducing triboelectric charge transfer. We analyse this process by coupled Discrete Element Method and Computational Fluid Dynamics (DEM-CFD) simulations, incorporating triboelectric charge transfer. The simulations are based on property data of glass ballotini as model particles, together with those of α-lactose monohydrate (α-LM) and aspirin, as powders of practical interest. The characteristics of particle-particle and particle-wall collisions are analysed in detail. The analysis shows that pharmaceutical particles charge significantly more than glass ballotini. The charge-to-surface area ratio is remarkably constant and close to its equilibrium value for each test material. Overall, the analysis provides a great insight on the triboelectric charging by aerodynamic dispersion.