Research On Some Key Technologies And Application System For Detection Microarray Information Processing

As a powerful biological technology, microarray analysis has been widely used in the field of environmental monitoring, judicature practice, drug screen and biological warfare agent detection. Detection microarray, which is a kind of low-density microarray used in biological detection, provides a fast, reliable, accurate and high throughput approach for microorganism detection. In this thesis, some key problems in detection microarray information processing are discussed, and algorithms for prob design, image denoising and spot identification are presented and tested. Application of the technique developed in this thesis into the personal medication system is also reported.To construct an automatic probe design system, a theoretical model for probe selection is firstly presented, transforming the design as an optimization problem. A fitness function is defined to evaluate the utility of a promising probe set, which take into consideration the comparability of probe sequences and other experimental conditions. The niche genetic algorithm is used to search the optimal probe combination based on the fitness function. Simulation results show that this approach is both efficient and accurate.Two methods are studied to remove noises in microarray image. In spatial domain, according to the Gaussian probability distribution model of noises, an adaptive weighted mean filter based on image amplitude and spatial position is used; while in the wavelet domain, according to the generalized Gaussian distribution model of sub-band wavelet coefficients, the threshold algorithm based on Bayesian estimation is used for denoising. Results show that both methods can suppress noise effectively while preserving image details very well.Based on the features of microarray image recognized, an automatic spot identification method using the deformable template technique is proposed. A deformable template model is constructed based on spot array. The shift, rotation and zoom of the template are denoted by several parameters. Energy function is defined and genetic algorithm is employed to search the optimal solution of the energy function, which results the best template match.After the theoretical and technical research, we also use the resulted technique to develop a prototype for personal medication system. The diagram of the syetem is illustrated, the module for microarray scan and analysis is studied and implemented.