Abstract: In some aspects, improved hydrogel copolymers (e.g., comprising itaconic acid and N-vinylpyrrolidone) are provided and may be used, e.g., for oral delivery of a therapeutic protein. In some embodiments, improved methods for loading a therapeutic protein (e.g., a high isoelectric point protein) into a hydrogel copolymer are provided, and may comprise incubating the therapeutic protein and the hydrogel in a reduced ionic strength loading solution. In some embodiments, use of the reduced ionic strength loading solution can result in hydrogel copolymer-therapeutic protein compositions that display improved pharmacokinetic attributes, e.g., improved loading and/or release of a therapeutic protein.

Abstract: A method of locating one or more reflectors in an environment crowded with reflectors. A transmitter and multiple receivers are used to obtain reflected signals. Each path of a reflected signal is defined by an ellipse having the transmitter at one focus and a receiver at the other. A reflector is assumed to lie on the ellipse, and an intersection of ellipses is assumed to be a reflector location. The region is iteratively divided into smaller and smaller cells, and a search algorithm is performed to determine whether a given point in each cell lies on an ellipse. A “solution” is a point that lies on the same number of ellipses as the number of receivers.