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The optimization of operating conditions is vital for cell culture process development. In the present study, the pilot-scale single-use bioreactor XcellerexTM XDR-200, which is typically used in cell culture scale-up, is investigated. This unbaffled reactor is equipped with an off-centered, bottom mounted impeller, and has a maximum working volume of 200 L. The flow field for this sparsely investigated bioreactor configuration is studied with computational fluid dynamics. Moreover, numerical simulations of the mixing time and the volumetric oxygen mass transfer coefficient for seven different test conditions are validated against experimental data. Mixing times across all tested conditions are found to remain below 30 s, and the volumetric oxygen mass transfer coefficient is between 2.0 to 20.0 h−1, which is a typical range for animal cell culture processes. These values of the oxygen transfer coefficient are found for as low as 0.004 to 0.125 L L−1 min−1 sparging rates with the microporous sparger. The hydrodynamic stress remains below critical values for cell damage for all conditions investigated. Vortex formation is suppressed in the bioreactor even though it is unbaffled due to off-centered impeller. Across the test conditions, the highest investigated impeller speed of 200 rpm is the most favorable due to fast mixing and high oxygen transfer.

The focus of this study is to establish a characterization method determining the powder flowability in context of tableting. At first, flowability of different materials is measured using the ring shear tester, and its prediction from particle size is established. Next, the model die-filling system is presented which is a modified version of previous studies. Using this system, flowability of different materials is measured at varying die speeds. A new curve fit to assess die fill ratio vs die speed is suggested improving predictability, and a novel flowability metric, "Die Fill Index" (DFI), is derived. The DFI is appropriate to describe flowability for most of the tested materials, and sensitivity of a material with respect to tableting speed. A correlation is generated predicting DFI from particle size. Additionally, it is shown that model die filling is the preferable method to assess flowability for tableting compared to ring shear tester.

A signal analysis system with memory-programmable automatic process control for determining power consumption in a high-shear mixer is described. A measuring transformer for unbalanced loads and special cascade transformers with controllable amplification stages allows highly accurate measurements to be made. The signal analyis system makes it possible to perform gliding mean value calculations of the measuring signal and to evaluate the signal fluctuations. The granulation end point is determined by curve analysis. Using this system, granules with a reproducible particle size distribution are obtained from active ingredient/excipient mixtures which either show a tendency to form lumps in the case of overwetting (paracetamol) or require a short granulation time due to low melting points (ibuprofen). The software, which allows the flexible setting of several system parameters, permits optimal adjustment to the behaviour of specific products.

Objective This study was intended to describe the neuropsychological phenomenology of focal nonconvulsive status epilepticus (NCSE). Methods Ictal, postictal, and interictal neuropsychological testing (NPT) was performed on six patients who developed NCSE during video/electroencephalographic monitoring in the context of presurgical evaluation. Results Neuropsychological impairments were marked in four of six and discrete in two of six patients. The majority of patients had selective rather than global neuropsychological deficits. The most important deficits involved consciousness, speech, praxis, cognitive functions, and affect. Impairment of consciousness was characterized by reduced vigilance, reactivity, and orientation. Some patients exhibited combined deficits of several higher cognitive functions (apraxia, acalculia, alexia, and aphasia with or without additional memory disturbance). Several patients had relatively subtle expressive or receptive aphasia. More severe language deficits were associated with reduced vigilance. Speech deficits may have caused poor performance in other areas evaluated with NPT. Conclusion NPT demonstrated that focal NCSE can be associated with pleomorphic but often discrete neuropsychological deficits.