A punch for making a decorative buckle design on a sheet medium. There is also provided an inkjet recording method that includes a step of discharging the ink composition onto a recording medium, and a step of curing the ink composition by irradiating the discharged ink composition with actinic radiation. A plurality of edge sections are removable from and replaceable to the board body, and each edge section has an engaging region complementary to the recessed area of the board body. The method further involves separating one or more signals from the plurality of impedance signals using a signal separation technique, such as an algorithm-based separation technique. In particular, the present invention provides blocker oligonucleotides that at least partially inhibit the formation of invasive cleavage structures with the interfering sequences but do not substantially inhibit the formation of invasive cleavage structures with the target sequences.