Berliner Gramophone formulations remained the standard disc record material until the first vinyl records – initially made only for radio use and other special applications – were introduced in the 1930s. Beginning in 1896, Berliner's gramophones were made by Philadelphia-based machinist Eldridge Johnson, who added a spring motor to drive the previously hand-rotated turntable. Berliner also opened an office in New York City, staffed by Frank Seaman and O. D. LaDow and organized as the National Gramophone Company. Master recordings were made onto zinc plates, which were then electroplated and a negative-image "mother" made from them to stamp discs. A major reversal
Temperature-responsive polymer covalently linked gels the polymers chains are not covalently linked together. That means that the gel could re-dissolve in a good solvent under some conditions. Thermoresponsive physical gels, also sometimes called thermoresponsive injectable gels have been used in Tissue Engineering. This involves mixing at room temperature the thermoresponsive polymer in solution with the cells and then inject the solution to the body. Due to the temperature increase (to body temperature) the polymer creates a physical gel. Within this physical gel the cells are encapsulated. Tailoring the temperature that the polymer solution gels can be challenging because this depend by many