Abstract: A 3D printer may precisely control deposition of diffusible chemical signals in different spatial regions of a solid polymer structure, in such a way that the concentration and spatial distribution of each diffusible chemical signal in each spatial region of the structure is independently controlled. A hydrogel containing genetically engineered, living organisms may be applied to a surface of the solid polymer structure. The living organisms may be single-celled organisms, such as bacteria. The diffusible chemical signals may diffuse out of the solid polymer structure and into the hydrogel, and may control gene expression of genetically engineered cells in different spatial locations in the hydrogel. Thus, gene expression of genetically-engineered cells in a hydrogel may be controlled on a region-by-region basis, by precisely controlling the position and concentration of diffusible chemical signals that are initially embedded in a solid structure adjacent to the hydrogel.

Abstract: An apparatus for reminding individuals when to take a medication, in a first embodiment 10 is a mechanical timer with different varieties of pegs 18 disposed to ring an alarm when a medication is to be taken and indicative of the medication by their style. A second embodiment 10A actually dispenses the medication that is required at that time. A third embodiment 56 is in the form of a wrist watch and displays 64 the medication and (any caveats) that is to be taken. A fourth embodiment 56A is pre-programmed so that the patient cannot tamper with the settings. The invention is apt for multi-medication multi-dose time situations.