In particular, a preferential
nucleation site and direction-dependent pinning of domain walls are observed due to slow kinetics of metastable switching in the sample without a bottom electrode. These in situ spatially resolved observations of a first-order bias-induced phase transition reveal the mesoscopic mechanisms underpinning functionality of a wide range of multiferroic materials. (C) 2011 American Institute of Physics. [doi:10.1063/1.3623779]“
“Emerging CCI-779 in vitro evidence suggests that an intact DNA damage response (DDR) serves as a potent barrier to malignant transformation. Using immunohistochemistry and patient-derived biopsy samples, we investigated whether the same may hold true during oral carcinogenesis. DNA damage accumulates early in the development of oral squamous cell carcinoma (OSCC) as evidenced by the detection of surrogate DDR biomarkers gamma-H2A.X and phosphorylated CHK2-threonine-68 (phospho-CHK2(Thr68)) in epithelial hyperplasias. However, whereas gamma-H2A.X expression peaked in dysplastic epithelium, its levels were significantly reduced in OSCCs (chi(2) = 7.655; P = .02). In contrast, there was a trend toward increased phospho-CHK2(Thr68) expression with increasing severity of the pathology. Nonetheless, combined expression of the biomarkers was significantly greater in
the nontransformed tissues relative to OSCCs (chi(2) = 6.42; P = .04). Thus, our findings suggest that early therapeutic exploitation of the DDR
may be worthy of investigation as a means by which to limit OSCC development. (Oral Surg Oral Med Oral Pathol selleckchem Oral Radiol Endod 2011;111:346-353)”
“The morphology evolution of miscible blends of a semicrystalline polyamide ACY-241 6 (PA6) and an amorphous polyamide 6Ico6T (PA6IcoT) was investigated using an internal Brabender mixer at a temperature range 220-260 degrees C. Morphology of the blends was characterized by scanning electron microscopy (SEM) and laser particle analysis. Temperature rising dissolution was used to separate the different phases of the blends and the phase compositions were determined by Fourier transform infrared (FTIR) spectroscopy. The particle size evolution of the dispersed phase (PA6) was calculated and agreed well with experimental observation. It was found that the particle size was quickly reduced to nanometer scale after several minutes of processing. A convection-diffusion model was adopted to study the phase evolution during meltmelt mixing stage and compute the dimension of each phase. The results strongly support the notion of existence of distinct phases during blending, whose development can be well described by the model. The dispersed phase is reduced mainly by stretching of flow, while the broadening of the blending phase can be primarily attributed to molecular diffusion.