Bioautomation

Volume 9
Editorial
Worldwide Scientist
Anniversary
New Books
Forthcoming Events
Journal Presentation
In Memoriam
Bioprocess Systems
Application of the Lyapunov Exponent to Evaluate Noise Filtering Methods a Fed-batch Bioreactor for PHB Production	1-14
Pratap R. Patnaik [ +/- abstract ][ full text ]
Large-scale fed-batch fermentations are often subject to noise carried by the feed streams. This noise corrupts the process data and may destabilize the fermentation. So it is important to retrieve clear signals from noisy data. This is done by noise filters. The performances of some commonly used filters have been studied for poly-β-hydroxybutyrate production by Ralstonia eutropha. In simulated experiments, Gaussian noise was added to the flow rates of the carbon and nitrogen substrates. The filters were compared by means of the Lyapunov exponents of the outputs and their closeness to the noise-free performance. Negative exponents indicate a stable fermentation. An auto-associative neural filter performed the best, followed by a combination of a cusum filter and an extended Kalman filter. Butterworth filters were inferior and inadequate.
Optimal Biocompatible Solvent Design Mixed-integer Hybrid Differential Evolution	15-30
Hou-Chieh Cheng, Feng-Sheng Wang [ +/- abstract ][ full text ]
In this study, a flexible optimization approach is introduced to design an optimal biocompatible solvent for an extractive fermentation process with cell-recycling. The optimal process/solvent design problem is formulated as a mixed-integer nonlinear programming model in which performance requirements of the compounds are reflected in the objectives and the constraints. A flexible or fuzzy optimization approach is applied to soften the rigid requirement for maximization of the production rate, extraction efficiency and to consider the solvent utilization rate as the softened inequality constraint to the process/solvent design problem. Such a trade-off problem is then converted to the goal attainment problem, which is described as the constrained mixed-integer nonlinear programming (MINLP) problem. Mixed-integer hybrid differential evolution with multiplier updating method is introduced to solve the constrained MINLP problem. The adaptive penalty updating scheme is more efficient to achieve a global design.
Ratiometric Alcohol Sensor based on a Polymeric Nile Blue	31-39
Nirmala Chandrasekharan, Sherif Ibrahim, Yordan Kostov, Govind Rao [ +/- abstract ][ full text ]
We present a sterilizable ratiometric fluorescent ethanol sensor with sensitivity over a wide range (0-100%) of ethanol concentration v/v. The sensor is composed of a near infra red fluorescent solvatochromic dye, nile blue methacrylamide polymerized into a polyethylene (glycol) dimethacrylate matrix. The dye can typically exhibit two or more wavelength dependent shifts in the fluorescence intensities based on its different micropolar environments. Two different concentrations of the nile blue methacrylamide dye were prepared and polymerized into homogenous films. The fluorescence properties of the two different films were investigated with a view to determining their ethanol sensing capabilities. The sensor was immersed in a water-ethanol solvent mixture. Excitation of the dye was performed at 470 nm. The range of emission wavelengths was 480-800 nm. The ratio of the fluorescence intensities at 620 nm and 554 nm was obtained for ethanol concentrations varying from 0-100% and the calibration curve of the ratiometric fluorescence intensities over the entire concentration range of ethanol was plotted. A ratiometric intensity change of over 33% has been obtained for pure ethanol compared to that obtained for pure water. The sensor response was rapid (≤10 minutes). The sterilizable ethanol sensor exhibits good potential for on-line monitoring of the ethanol generated in an LB fermentation chamber.
Biomedical Systems
Screening Models for Cardiac Risk Evaluation in Emergency Abdominal Surgery. I. Evaluation of the Intraoperative Period Risk based on Data from the Preoperative Period	40-49
Maria Milanova, Mikhail Matveev [ +/- abstract ][ full text ]
A classification of intraoperative cardio-vascular complications (CVC) was performed, based on data from 466 patients subjected to emergency surgery, due to severe abdominal surgical diseases or traumas, in accordance with the severe criteria of ACC/AHA for CVC in noncardiac surgery. There were 370 intraoperative CVC registered, distributed as follows: groups with low risk (148), moderate risk (200), and high risk (22). Patient groups were formed, according to the CVC risk level, during the intraoperative period, for which the determinant factor for the group distribution of patients was the complication with the highest risk. Individual data was collected for each patient, based on 65 indices: age, physical status, diseases, surgical interventions, anaesthesiological information, intra and postoperative cardio-vascular complications, disease outcome, causes of death, cardiovascular disease anamnesis, anamnesis of all other nonsurgical diseases present, laboratory results, results from all imaging and instrumental examinations, etc. On the basis of these indices, a new distribution of the risk factors was implemented, into groups with different levels of risk of CVC during intraoperative period. This result is a solid argument, substantiating the proposal to introduce these adjustments for determining the severity of CVC in the specific conditions of emergency abdominal surgery.
Screening Models for Cardiac Risk Evaluation in Emergency Abdominal Surgery. II. Evaluation of the Postoperative Period Risk based on Data from the Pre- and Intraoperative Period	50-58
Maria Milanova, Mikhail Matveev [ +/- abstract ][ full text ]
A classification of intraoperative (IO) and postoperative (PO) cardio-vascular complications (CVC) was performed, based on data from 466 patients subjected to emergency surgery, due to severe abdominal surgical diseases or traumas, in accordance with the severe criteria of ACC/AHA in CVC for non-cardiac surgery. There were 370 intra and 405 postoperative (IO; PO) CVC registered, distributed as follows: groups with low risk (IO: 148; PO: 87), moderate risk (IO: 200; PO: 225), and high risk (IO: 22; PO: 93). Patient groups were formed, according to the CVC risk level, during the intra- and postoperative periods, for which the determinant factor for the group distribution of patients was the complication with the highest risk. Individual data was collected for each patient, based on 65 indices: age, physical status, diseases, surgical interventions, anaesthesiological information, intra and postoperative cardio-vascular complications, disease outcome, causes of death, cardio-vascular disease anamnesis, anamnesis of all other nonsurgical diseases present, laboratory results, results from all imaging and instrumental examinations, etc. The trend toward increase or decrease of the CVC risk was studied during the transition from intra- to the postoperative period. On the basis of these indices, a new distribution of the patients was implemented, into groups with different levels of risk of CVC during intra- and postoperative. This result is a solid argument, substantiating the proposal to introduce these adjustments to the ACC/AHA criteria for determining the severity of CVC in the specific conditions of emergency abdominal surgery.
Meta-analysis in Medicine: Implementation in Hypertension and Renal Disease in Diabetes Mellitus	59-68
Yee Hung Choy, Anthony Shannon [ +/- abstract ][ full text ]
This paper utilises meta-analysis and odds ratios to examine the relationship between hypertension and kidney disease in patients with diabetes (Type 1 or Type 2). Significant evidence is found to establish that our quantitative results (overall odds ratios) agree with the qualitative results of the literature, namely that hypertension has a close association with nephropathy and is a major risk factor for this renal disease. The results show that with hypertension diabetic patients have almost 3.5 times the risk of developing nephropathy than those diabetic patients without hypertension.
Principle Generalized Net Model of a Human Stress Reaction	69-78
Vihren Chakarov, Anthony Shannon, Krassimir Atanassov [ +/- abstract ][ full text ]
The present study was aimed at investigating the mechanism of a human stress reaction by means of Generalized Nets (GNs). A principle GN-model of the main structures, organs and systems of the human body taking part in the acute and chronic reaction of the organism to a stress stimulus is generated. A possible application of the GN-model of the human stress reaction for testing the effect of known or newly synthesized pharmacological products as well as of food supplements is discussed.
Ecological Systems
Comparative Analysis of Two Models of the Strouma River Ecosystem	79-87
Tatiana Ilkova, Mitko Petrov [ +/- abstract ][ full text ]
A modified method of regression analysis for modelling of the water quality of river ecosystems is offered. The method is distinguished from the conventional regression analysis of that the factors included in the regression dependence are time functions. Two type functions are tested: polynomial and periodical. The investigations show better results the periodical functions give. In addition, a model for analysis of river quality has been developed, which is a modified method of the time series analysis. The model has been applied for an assessment of water pollution of the Strouma river. An assessment for adequately of the obtained model of the statistical criteria - correlation coefficient, Fisher function and relative error is developed and it shows that the models are adequate and they can be used for modelling of the water pollution on these indexes of the Strouma river. The analysis of the river pollution shows that there is not a materially increase of the anthropogenic impact of the Strouma river in the Bulgarian part for the period from 2001 to 2004.