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Aiming at suppressing the vibration of low-frequency, a procedure of dynamic optimization of wafer handling robot is presented. The dynamic model of wafer handling robot is firstly build, and following that the dynamic characteristics of the robot are analyzed to find the main parameters which will influence the natural frequency. Then, the numerical procedure of the optimization of the natural frequency is introduced, and the constraint functions are obtained by considering the workspace and the structure of the robot. And at the end, as a case study, the procedure is applied to a wafer handling robot. Optimization result shows that the natural frequency is enhanced to 32.56Hz after the optimization.

Mig1p, a zinc finger class of DNA-binding protein, plays a critical role in glucose repression for maltose utilization in Baker’s yeast. Maltose is the hydrolyzate of starch, which is the main component of dough. In this study, the recombinant yeast strains with MIG1 gene deletion were constructed, and the maltose metabolism of the parental and mutant strains in batch cultivations were investigated. Our results show that the degree of glucose repression of mutants △MIG1α and △MIG1a are reduced by 49.88% and 41.59% respectively compared to their parental strains, suggesting that MIG1 deletion can partially relieve glucose repression of maltose metabolism.

A polyelectrolyte complex (PEC) composed of chitosan (CS) and phosphorylated chitosan (PCS) was used to encapsulate a calcium phosphate by a biomimetic method. An acidic CS (polycation) solution containing calcium and phosphate ions (Ca2+: 6mM, Ca/P = 1.67) was added into PCS (polyanion) solution leading to the formation of a polyelectrolyte complex (PEC) with nanoscopic carbonate-containing, low-crystallinity hydroxyapatite (HA) distributed evenly in the fibrils of the PEC by controlled crystal growth. The resulting composite material, PEC-HA, has a complicated, hierarchical porous structure that is expected to have high bio-compatibity and that may be of use as a carrier for controlled-release therapetic agents.