An envelope comprising a tear strip that functions as an efficient opening means for access to the envelope contents. During the on time, the receiver sequentially is open to receive a first signal with a first baud rate. In another embodiment, the face mask of the present invention further comprises an outer seal connected the perimeter of the air-permeable body. The midship hull section is preferably constructed in a specialized shipyard, and the same shipyard installs drilling equipment and equipment that connects to risers that bring up hydrocarbons, so the expertise of the shipyard is used for both the midsection hull construction and specialized drilling and riser handling equipment. The invention also provides a method for measuring glycated proteins such as glycated hemoglobin and glycated albumin and for measuring their decomposition products fructosylamines, such as fructosylvaline, as well as assay reagents and sensors for use in the method.