Bioprocess applications of model-based estimation techniques

The last decade has seen the development of a number of approaches for estimating those variables which are difficult to measure on-line in industrial process situations. Whilst a range of techniques is available, a common element is the use of process knowledge in the form of a system model. In the case of bioprocess systems, although a large range of models has been presented in the literature, their use in estimation schemes on an industrial scale has been limited. A number of reasons can be identified for their low level of utilisation. Of particular significance is the uncertainty which exists in quantifying system performance and the process-model mismatch which inevitably results. The level of ‘pre-defined model’ uncertainty, together with the knowledge gained during the course of the fermentation, serves to dictate estimator structure. The paper considers a range of estimation strategies and contrasts, through industrial applications, their performance characteristics and utility.     

Attentional control within 3-D space

Four experiments investigated whether directing attention to a particular plane in depth enables observers to filter out information from another depth plane. Observers viewed stereoscopic displays and searched for a red line segment among green line segments. The results showed that directing attention to a particular depth plane cannot prevent attentional capture from another depth plane when the colors of the target and distractor are identical. However, it can prevent attentional capture by a singleton from another depth plane when the colors of the target and distractor are different. These results indicate that only when both color and depth information are selective in guiding attention to the target singleton can attentional capture by irrelevant singletons be prevented. The results also suggest that retinal disparity does not have the same special status as location information in two dimensions and should be considered as just another feature along which selection may occur.     

Clinical and functional evaluation of health status of workers exposed to infrasound, noise and general vibration

The article covers complex evaluation of health state in building industry workers engaged into ferro-concrete production in St. Petersburg. The health state was considered under combined action of infrasound, noise and general vibration. Clinical and functional evaluation included medical examination by doctors, blood biochemistry and CBC, ECG, computer integral rheography, voice audiometry. Data for 62 moulders helped to assess acoustic environment at workplace and to reveal the morbidity structure.     

Flow regime, hydrodynamics, floc size distribution and sludge properties in activated sludge bubble column, air-lift and aerated stirred reactors

This paper presents a comparative study how reactor configuration, sludge loading and air flowrate affect flow regimes, hydrodynamics, floc size distribution and sludge solids-liquid separation properties. Three reactor configurations were studied in bench scale activated sludge bubble column reactor (BCR), air-lift reactor (ALR) and aerated stirred reactor (ASR). The ASR demonstrated the highest capacity of gas holdup and resistance, and homogeneity in flow regimes and shearing forces, resulting in producing large numbers of small and compact flocs. The fluid dynamics in the ALR created regularly directed recirculation forces to enhance the gas holdup and sludge flocculation. The BCR distributed a high turbulent flow regime and non-homogeneity in gas holdup and mixing, and generated large numbers of larger and looser flocs. The sludge size distributions, compressibility and settleability were significantly influenced by the reactor configurations associated with the flow regimes and hydrodynamics.     

Breast micro-opacities of lead origin mimicking microcalcifications

After a surgical excision of focal mammary "microcalcification" we noticed that in fact they represented fine lead deposits (mean diameter: 100 microns) resulting from an attempted suicide (22 long rifle) 10 years previously. The leaded nature of these foreign microbodies was demonstrated by a micro-analysis by energy dispersion on histological slides.     

Computer modelling and analysis of the photodegradation effect in a-Si:H p-i-n solar cell

Using a previous model, which was developed to describe the light-induced creation of the defect density in the a-Si:H gap states, we present in this work a numerical modelling of the photodegradation effect in the a-Si:H p-i-n solar cell under continuous illumination. We first considered the simple case of a monochromatic light beam with a wavelength λ between 530-540 nm non uniformly absorbed, then the global standard solar spectrum (AM 1.5) illumination is taken into account. The photodegradation is analysed on the basis of the resulting changes in the free carrier's densities, recombination rate, band structure, electrical potential and field, space charge, and current densities. Changes in the cell's external parameters: the open circuit voltage V_oc, the short circuit current density J_sc, the fill factor FF and the maximum power density P_max are also presented.     

Parameters for the measurement of long-term effects of an orally administered drug in organic and functional circulatory disorders. Preliminary communication

In many cases of drug-induced allergic hepatitis, peripheral lymphocytes were transformed by the stimulation with a given drug in the presence of autologous serum. However, when rat liver microsome fraction of soluble liver specific antigen fraction was added to the culture instead of autologous serum, the drug-induced lymphocyte transformation was more efficiently seen than autologus serum, while rat liver mitochondria fraction was less effective. On the other hand, in the cases of allergic drug eruption which did not show any liver injury, the addition of liver subcellular fractions were much less effective to induce the lymphocyte transformation than autologous serum. These results may suggest that liver subcellular component is involved in pathogenesis of drug-induced allergic hepatitis.     

Psychological differentiation and psychotherapy

Patient's level of psychological differentiation was studied in relation to patients' and therapists' evaluations of the initial psychotherapy session. The evaluations assessed two broad dimensions of the interaction which generally have been considered important for psychotherapeutic success and which have been found to be related to patients' psychological differentiation: namely, patients' and therapists' satisfaction with the amount of structure, and therapists' impressions of patients' appropriateness for therapy. Significant correlations were obtained between patients' psychological differentiation and both of these dimensions. However, two control variables, socioeconomic status and alcohol use, were also found to be related to these dimensions. When the effects of these variables were partialed out, the relationships with therapists' impressions of appropriateness disappeared, but the relationships with patients' and therapists' satisfaction with the amount of structure remained significant. The relationship of these findings to other studies of psychological differentiation and psychotherapy is discussed. Finally, the contribution of the present results to the choice of the most appropriate measure of psychological differentiation is noted.