Volume 11, suppl.
Selected papers from 21st International Symposium "Bioprocess Systems 2008 - BioPS'08"
Bioprocess Systems
Equivalent Forms of Wang-Yerusalimsky Kinetic Model and Optimal Growth Rate Control of Fed-batch Cultivation Processes1-12
Pavlov Y.
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In the paper is presented a control design for optimal control and stabilization of the specific growth rate of fed-batch biotechnological processes. The control design is based on a Wang-Yerusalimsky kinetic model and its equivalent Brunovsky normal form. The control is written based on information of the growth rate.
Functional States Recognition System for Fed-batch Cultivation of Saccharomyces cerevisiae13-22
Ljakova K., Pencheva T.
[ +/- abstract ][ full text ]
Free software for entering and documenting data EpiData is here used for design of a system for functional states recognition during a fermentation process. The identification of the current process state is based on the predetermined rules, rendering specific metabolic mechanisms. Developed system is further applied for a fed-batch cultivation of Saccharomyces cerevisiae.
An Advisory System for On-line Control of Fed-batch Cultivation of Saccharomyces cerevisiae23-32
Pencheva T., Ljakova K.
[ +/- abstract ][ full text ]
Free software for entering and documenting data EpiData is here used for design of an advisory system for on-line control of a fermentation process. Based on the preliminary developed system for functional state recognition, presented here system will advise the user which new functional state can be reached and what kind of control actions have to be taken. New-designed system appears as an expert system and comprises knowledge of well-trained operators of cultivation processes. Developed advisory system is further applied for a fed-batch cultivation of Saccharomyces cerevisiae.
Biomedical Systems
Reduction of Dimensionality of a Dynamical Model of Aggressive Tumor Treated by Chemotherapy, Immunotherapy and siRNA Infusion. Part ≤. Establishment of Time Hierarchy in the Model Dynamics33-40
Nikolova E.
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The Tichonovís theorem for quasi-stationary approximation is considered as a basic approach for reduction of dynamical systems with time hierarchy. On the basis of previously determined parameters, seven ordinary differential equations of the dynamical model of tumor treated by chemotherapy, immunotherapy and siRNA infusion are written in a form appropriate to evaluate their terms for model reduction. In accordance with the terminology of the Tichonovís theorem, it is established that three of the system components are fast varying such that the corresponding kinetic equations form an attached system. The other four variables are slow varying and their kinetic equations form a degenerate system
Identification of the Parameters of the Tumor Therapy Process at Viral Hepatitis B49-56
Edissonov I., Nikolova E., Ranchev S.
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A generalized mathematical model of the tumor therapy process is considered as a nonlinear system of ordinary differential equations. Parameter identification of the model is carried out using experimental data of patients with viral hepatitis B. As a result of the identification procedure numerical values of the model coefficients are obtained. It is shown that the experimental clinical data are maximal near to the theoretical curves obtained by numerical simulations of the model.
Time-Frequency Spectral Differences in Event-Related Potentials between Neurotic and Stable Persons in Human EEG57-64
Georgiev S., Minchev Z., Philipova D., Christova C.
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The aim of this work is to show how Wavelet and S-transform Power Spectrum Analysis could be used for detection of the time-frequency spectral differences in series of Event-Related Potentials recorded from neurotic and stable persons. We compared the EEG records in simple counting task condition of 30 healthy subjects divided in stable and neurotic groups according to there scores in neuroticism scale on Eysenckís Personality Questionnaire. Significant differences were found in the theta and alpha EEG bands. The stable persons are characterized with more prominent theta and less prominent alpha spectral power compared to the neurotic group. The application of complex decomposed functions for both Wavelet and S-transform Power Spectrum Analysis showed to be more useful for the discrimination between both groups of subjects.
Ecological Systems
Investigation of the Properties of Immobilized Horseradish Peroxidase on Magnetic Particles65-72
Yotova L., Ivanov T., Mironova V., Chuchuranova V.
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Magnetic particles coated with copolymer of acrylamide and acrylonitrile have been prepared. Those particles were used as a matrix for a covalent binding of peroxidase. The periodic-oxidized enzyme was bound to the matrix by immobilization procedure at 4įC for 18 hours. The immobilized enzyme showed relative activity of 86%. The following results were obtained for pH and optimum temperature of the immobilized enzyme - 7.0 and 30įC, respectively. The analysis of the kinetic parameters of the immobilized enzyme showed values of Vmax - 0.0517 M.10-6/sec and Km - 2.3x10-4 M.
Application of the Ň–“-index for Ecological Status Assessment of the Riverine Water Bodies within the Basin of Kamchia River73-79
Moskova G., Soufi R., Uzunov Y.
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Indexes based on the intolerance of the groups Ephemeroptera, Plecoptera and Trichoptera to pollution were used for assessment of the ecological status along the river system of Kamchia. The achieved data about the EPT-indexes were compared with standard biological indexes for water quality assessment of the surface running waters, according to Ordinance No.7/1986 (Appendix 1). The results from the survey illustrated that the values of the Ň–“-N and Ň–“-S indexes confirm the assessment for the sapro-biological conditions along the Kamchia river valley. These indexes efficiently establish the changes in the water quality and successfully can be used for the purposes of ecological categorization of the river water bodies.

© 2008, BAS, Institute of Biophysics and Biomedical Engineering