Dual-tracer background subtraction approach for fluorescent molecular tomography

Diffuse fluorescence tomography requires high contrast-to-background ratios to accurately reconstruct inclusions of interest. This is a problem when imaging the uptake of fluorescently labeled molecularly targeted tracers in tissue, which can result in high levels of heterogeneously distributed background uptake. We present a dual-tracer background subtraction approach, wherein signal from the uptake of an untargeted tracer is subtracted from targeted tracer signal prior to image reconstruction, resulting in maps of targeted tracer binding. The approach is demonstrated in simulations, a phantom study, and in a mouse glioma imaging study, demonstrating substantial improvement over conventional and homogenous background subtraction image reconstruction approaches

High-pressure x-ray diffraction and Raman spectroscopy of Hf V 2 O 7

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High-pressure Raman and infrared study of ZrV2O7ZrV_2O_7

The room-temperature Raman and infrared spectra of zirconium vanadate $(ZrV_2O_7)$ were observed up to pressures of 12 GPa and 5.7 GPa, respectively. The frequencies of the optically active modes at ambient pressure were calculated using direct methods and compared with experimental values. Average mode Grüneisen parameters were calculated for the Raman and infrared active modes. Changes in the spectra under pressure indicate a phase transition at not, vert, similar \sim 1.6 GPa, which is consistent with the previously observed \alpha (cubic) to $_\beta$ (pseudo-tetragonal) phase transition, and changes in the spectra at not, vert, similar \sim 4 GPa are consistent with an irreversible transformation to an amorphous structure

High-pressure Raman and infrared study of ZrV2O7

The room-temperature Raman and infrared spectra of zirconium vanadate (ZrV2O7) were observed up to pressures of 12 GPa and 5.7 GPa, respectively. The frequencies of the optically active modes at ambient pressure were calculated using direct methods and compared with experimental values. Average mode Gruneisen parameters were calculated for the Raman and infrared active modes. Changes in the spectra under pressure indicate a phase transition at similar to 1.6 GPa, which is consistent with the previously observed a (cubic) to (pseudo-tetragonal) phase transition, and changes in the spectra at similar to 4 GPa are consistent with an irreversible transformation to an amorphous structure. (C) 2007 Elsevier Ltd. All rights reserved