25 at% Eu doped BNBT6 ceramic presents excellent electrical properties: piezoelectric constant d(33)=149 pC/N, remnant polarization P-r=40.27 mu C/cm(2), coercive field E-c=2.95 kV/mm, dielectric constant epsilon(r)=1658 and dissipation factor tan delta=0.0557 (10 kHz). (C) 2013 Elsevier Ltd and Techna Group S.r.l. All rights reserved.”
“In the search for improved imaging modalities
for detection and diagnosis of breast cancer, a high negative prediction value is also important. Photoacoustic (optoacoustic) imaging is a relatively new technique that has high potential for visualizing breast malignancies, but little is known about the photoacoustic appearance of benign lesions. In this work, we investigate the visibility of benign breast cysts in forward-mode photoacoustic mammography using 1064-nm light, as currently applied in the Twente photoacoustic mammoscope. Results from (Monte Carlo and k-wave) simulations and phantom measurements selleck screening library were used to interpret results from patient measurements. There was a strong agreement among the results from simulations, phantom, and patient measurements. Depending on the absorption contrast between
cyst and breast tissue, cysts were visible as either one or two confined high-contrast areas representing the NU7441 front and the back of the cyst, respectively. This edge enhancement is most likely the consequence of the local sudden change in the absorbed energy density and Gruneisen coefficients. Although the current forward-mode
single-wavelength photoacoustic mammoscope cannot always unambiguously discriminate cysts from malignancies, this study reveals specific features of cysts compared to malignancies, which can be exploited for discrimination of the two abnormalities in future modifications of the imager. (C) The Authors.”
“Perinaphthenone (1H-phenalen-1-one, PN) is a reference photosensitizer producing singlet oxygen with a quantum yield close to one in a large variety of solvents. It is also the basic structure of a class of photo-toxic phytoalexins. In this work, the PN photoreactivity was studied for the first time AZD9291 mouse in a paraffinic wax, used as model of leaf epicuticular waxes. The PN photodegradation was monitored by UV-Vis spectroscopy. The triplet excited state, singlet oxygen and the hydroxyperinaphthenyl radical were detected by diffuse reflectance laser flash photolysis, near infrared phosphorescence and by EPR spectroscopy, respectively. The PN phototransformation was found to be fivefold faster in the wax than in n-heptane under steady-state irradiation. The hydroxyperinaphthenyl radical formation was observed in aerated irradiated paraffin wax while in n-heptane solution the radical was observed only in the absence of oxygen. These results show that under continuous irradiation, PN is much more easily phototransformed in a solid environment than in solution. Several photoproducts were identified, in particular phenalanone, PN dimers, and oxidized PN-alkanes adducts.