A closure device for use following various surgical procedures to close access openings through the tissue wall while permitting post operative flow through the tissue conduit includes a housing having proximal and distal ends, and defining a longitudinal axis. In essence, two or more modular filtration units are interlocked together to form a single cell system for processing water from aquaculture tanks. Requests to the file system for access to the image are filtered through the data set to prevent unintentionally revealed information in the image from being generally available. In another aspect, the method includes the steps of halogenating a polyarylsilane to form a halopolysilane; and reducing the halopolysilane with a metal hydride to form the polysilane.