Abstract: A synthetic hydrogel is described, including hydrated mucin glycoproteins cross-linked with multi-arm thiol functional cross-linker, which can be prepared to model viscoelastic and micro-rheological properties of natural mucus. Such synthetic hydrogel can be prepared from a wide variety of mucin raw materials. Also described is a method of microrheologically characterizing mucus, by dispersing in the mucus muco-inert particles (MIP), irradiating the mucus containing MIP with polarized light, and measuring fluorescence polarization (FP) resulting from rotational diffusion of the MIP in the mucus in response to such irradiating, as a microrheological characteristic of the mucus. This method can be carried out using a plate reader equipped with a spectrofluorometer and polarized filter set, and therefore can be readily carried out in clinical settings without the necessity of specialized microrheological equipment.

Abstract: An integrated circuit for implementing a resistor network on a die of the integrated circuit. The integrated circuit includes a common conductor, which is disposed on a first side of the die and coupled to resistors of the resistor network. The integrated circuit further includes a substantially conductive substrate through the die. There is further included a conductive back side contact coupled to the substantially conductive substrate. The conductive back side contact is disposed on a second side of the die opposite the first side, whereby the common conductor, the substantially conductive substrate, and the conductive back side contact form a common conducting bus from the common conductor to the conductive back side contact through the die.