Energy transfer from photoexcited porphyrin molecules to single-walled carbon nanotubes (SWNTs) has been experimentally detected for samples in aqueous Triton X-100 micellar suspensions. Addition of SWNTs to micelle-suspended porphyrin results in strong quenching of porphyrin fluorescence. Measurements of concentration-dependent quenching and spectra suggest that this process arises from formation of ground state non-covalent complexes between porphyrins and SWNTs. Optical excitation of the porphyrin generates characteristic near-IR emission from the SWNTs, indicating efficient energy transfer within the complexes. This energy transfer is deduced to occur through a Dexter-type electron exchange mechanism. Complexation of SWNTs with organic photosensitizers provides a novel way of uniformly exciting a wide range of nanotube structural species in polydisperse samples using only a single excitation wavelength.

Abstract:Traditionally diabetes education has relied on written materials, with limited resources available for children with diabetes. Mobile games can be effective and motivating tools for the promotion of children's health. In our earlier work, we proposed a novel approach for designing computer games aimed at educating children with diabetes. In this paper, we apply our game design to a mobile Android game (Mario Brothers). We also introduce four heuristics that are specifically designed for evaluating the mobile game, by adapting traditional usability heuristics. Results of a pilot study (n=12) to evaluate game play over 1-week showed that the children found the game engaging and improved their knowledge of healthy diet and lifestyle.

The extra- and intracapsular techniques evaluated in this study reduced CrCa tibial translation in CrCL deficient stifles to varying amounts.

An efficient new method is demonstrated for measuring length distributions of semiconducting single-walled carbon nanotubes (SWCNTs) through analysis of their highly polarized photoluminescence when aligned by shear flows. Instrumentation and procedures are developed to characterize nanotube lengths in bulk suspensions with rapid data acquisition and interpretation. Applying the method with spectrally resolved SWCNT emission provides the first measurements of (n,m)-specific length distributions. A positive correlation is found between average length and nanotube diameter, although this correlation is weaker following extensive sample centrifugation. Intense sonication shortened all nanotube species and had the strongest effect on those with small diameters. The new method should provide a useful alternative to atomic force microscopy for characterizing SWCNT lengths.