A system to obtain item information includes capture of an image of an item identifier, transmission of the image, and, in response to the transmission, reception of item information associated with an item identified by the item identifier. In particular, compositions are methods are provided for inhibition of interaction between a virus, especially HIV, and a receptor. The systems and methods significantly reduce lower-frequency emissions from pulse transmission spread-spectrum communication modes, which reduces potentially harmful interference to existing radio frequency services and users and also simultaneously permit transmission of multiple data bits by utilizing specific pulse shapes. In particular, when used for ligament replacement, the tissue retainer eliminates or at least minimizes the twisting that typically occurs during conventional surgery. The first sealing member is configured to seat against a seating located on the first body when the arm is in a rest position, the first seating being located between the gas outlet and the second cavity.