Circuits and methods to provide an LDO output stage implemented with low-voltage devices and still allowing higher voltage levels have been achieved. In certain example embodiments, the window structure includes a slidable window panel or sheet located between a pair of fixed window panels or sheets. The absorbent structure is characterized by that the pores of the foam structure contains hydrophilic fibers, at which at least the main part of the hydrophilic fibers are firmly anchored in the pore walls of the foam structure, and that the fiber amount is at least 10% by weight of the total weight of the open-cell foam in dry condition. 1 MPa to 700 MPa, at least within the portion which corresponds with the position of the cavity section, wherein by selectively compressing the cavity section from the external surface of the member andor the member, the volume of the cavity section can be reduced in a reversible manner. In other embodiments, a wire-core strap can include transverse ridges, holes, or other types of grooves or apertures.