Upsampling adds more pixels/dots per inch (dpi), but creates blurry images, ugly blocks of color, and high contrast in images. The only way resolution can be improved is by decreasing the image size, or by recapturing the image at a higher quality setting.
Postcrossing is an online project that allows its members to send and receive postcards from all over the world.
Definition of postnatal. : occurring or being after birth; specifically : of or relating to an infant immediately after birth postnatal care.