R. G. Zhang

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The crystal structure of the trp repressor/operator complex shows an extensive contact surface, including 24 direct and 6 solvent-mediated hydrogen bonds to the phosphate groups of the DNA. There are no direct hydrogen bonds or non-polar contacts to the bases that can explain the repressor's specificity for the operator sequence. Rather, the sequence seems(More)
Comparison of the crystal structure of inactive unliganded trp aporepressor with that of trp repressor shows that binding tryptophan activates the dimer a thousandfold by moving two symmetrically-disposed flexible bihelical motifs. These flexible 'DNA-reading heads' flank a highly inflexible core domain formed by an unusual arrangement of interlocking(More)
Nadolschi chaotic system is a system with intense non-linear behavior; chaotic systems are stable systems with unique behavioral characteristics. Very high sensitivity to parameters, the initial con ditions and pseudo-random behavior while having a simple structure are examples of these features. Considering numerous applications in various fields,(More)
Fuzzy data analyses on metal nanocluster composites prepared by Cu ion implantation have been studied. Fast nonlinear optical refraction and nonlinear optical absorption coefficients were measured at 790 nm for Cu nanocluster composites by the Z-scan technique. With the increase of annealing temperature, the size of nanoclusters increased significantly, and(More)
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