Structure and Conductivity of Semiconducting Polymer Hydrogels.

Poly(fluorene-alt-thiophene) (PFT) is a conjugated polyelectrolyte that self-assembles into rod-like micelles in water, with the conjugated polymer backbone running along the length of the micelle. At modest concentrations (∼10 mg/mL in aqueous solutions), PFT forms hydrogels, and this work focuses on understanding the structure and intermolecular interactions in those gel networks. The network structure can be directly visualized using cryo electron microscopy.

POLARON DYNAMICS. Long-lived photoinduced polaron formation in conjugated polyelectrolyte-fullerene assemblies.

The efficiency of biological photosynthesis results from the exquisite organization of photoactive elements that promote rapid movement of charge carriers out of a critical recombination range. If synthetic organic photovoltaic materials could mimic this assembly, charge separation and collection could be markedly enhanced. We show that micelle-forming cationic semiconducting polymers can coassemble in water with cationic fullerene derivatives to create photoinduced electron-transfer cascades that lead to exceptionally long-lived polarons.

Computerized self-monitoring and technology-assisted feedback for weight loss with and without an enhanced behavioral component.

Objective: The purpose of this study was to develop and evaluate a 12-week weight management intervention involving computerized self-monitoring and technology-assisted feedback with and without an enhanced behavioral component.

Methods: 120 overweight (30.5±2.