The present invention relates to, inter alia, pharmaceutical compositions comprising a polyunsaturated fatty acid and to methods of using the same to treat or prevent cardiovascular-related diseases. The guide mechanism of the present invention includes at least one guide passage which is protruded outwardly from the side wall of the chassis and has two guiding oblique surfaces at its both ends. The intersecting bond lines define unbonded pattern elements, each of the pattern elements being at least partially bounded by non-linear segments of the bond lines. 2,3-difluoro-4,6-dihydrothieno3,4-bthiophene is then oxidized with an oxidant to produce 2,3-difluorothieno3,4-bthiophene. The monomer is permitted to polymerize in the temporary container to form polymer. This view makes it clear that the slat cover strip will be moved into position proximate the vertical control cord hole when the slat is tilted.