For the join operator that is the most difficult to process and optimize in DBMS,the query optimization strategies, based on genetic algorithms, over the plan collections of left-deep join tree and the plan collections of bushy join tree are discussed.

Advances in study of novel absorption enhancers based on tight junctions;

Changes of tight junction claudin-1,-3,-4 protein expression in the intestinal mucosa in patients with irritable bowel syndrome;

Changes in tight junction of intestinal mucosa in patients with irritable bowel syndrome:a study with tracing electron microscope;

The system provides powerful security function because of adoption of SSL encryption connection and Servlet Techniques.

,link density and under the precondition that the size of networks remains unchanged,the effects of the heterogeneous distribution of degree and link density on the synchronizability of network are investigated and,based on the synchronization criterion,the synchroniabilities of two types of networks are explored.