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A novel characterization method using Raman scattering microscopy for basal plane stacking faults (SFs) and associated partial dislocations (PDs) in 4H-SiC crystals is proposed. Atomically thin SFs were successfully detected through the peak shift of the A1t transverse optical phonon mode in 4H-SiC, which could induce an electrical dipole moment within the SFs. The A1t mode was also sensitive to the strain field around the PDs encompassing SFs. Raman scattering microscopy imaging was able to determine the core type of PDs and their line direction within the crystals. Numerical simulation of Raman scattering microscopy images of PDs was also conducted and showed a quantitative agreement with the experimentally obtained images. Finally, the method was applied to the investigation of expansion behaviors of double Shockley SFs (DSSFs) in heavily nitrogen-doped 4H-SiC crystals during high temperature annealing and revealed several important aspects of DSSF expansion. [ABSTRACT FROM AUTHOR]

The formation of single Shockley stacking faults (SSSFs) in 4H-SiC crystals under non-equilibrium conditions (e.g., the forward biasing of PiN diodes and ultraviolet light illumination) is a key phenomenon in the so-called bipolar degradation of SiC power devices. This study theoretically investigated the physical mechanism of this phenomenon based on the concept of quantum well action. As a first approximation describing the non-equilibrium state of the material, we employed quasi-Fermi level approximation. We then made improvements by considering several physical effects governing the carrier distribution near and in the SSSF. The improved model accounts well for the excitation threshold and the temperature dependence of SSSF expansion. Thus, the model provides useful insights into the driving force of SSSF expansion under non-equilibrium conditions. [ABSTRACT FROM AUTHOR]

Abstract: Objective: It was shown that aerobic exercise training may protect against the development of atherosclerosis. However, the precise mechanisms are still unknown. We assessed the hypothesis that exercise training reduced the severity of experimental atherosclerosis in apolipoprotein (apo) E-deficient mice by antioxidant effects. Methods: Exercise training (45 min swimming, 3 times/week) was conducted on apo E-deficient mice fed a high fat diet. Over 8 and 16 weeks on alternate days, mice were treated with and without exercise, and additional exercise-treated mice were orally given 25 mg/kg/day of N G-nitro-l-arginine methylester (l-NAME), an inhibitor of nitric oxide synthase (NOS). In addition, the effect of l-arginine against l-NAME was also tested. Results: Fatty streak formation at 8 weeks and fibrofatty plaques at 16 weeks developed in apo E-deficient mice fed a high fat diet, and were suppressed in mice treated with swimming for 8 and 16 weeks. In contrast, atherosclerotic lesions were not ameliorated in mice treated with exercise training associated with oral l-NAME. However, in mice treated with swimming associated with l-NAME and l-arginine, the atherosclerotic lesions were reduced. Immunohistochemical analysis revealed that macrophage and CD4+ cell accumulation in the fatty streak lesions was suppressed in mice treated with exercise, but not in those treated with exercise associated with l-NAME administration. The severity of atherosclerotic lesions was inversely correlated with the endothelial NOS expression and the expression of an endogenous antioxidant protein, thioredoxin. Namely, the expression of thioredoxin in mice treated with exercise was suppressed compared with mice without exercise. Plasma thiobarbituric acid-reactive substance levels were significantly lower in groups with exercise than in those without exercise or with exercise associated with l-NAME administration, suggesting exercise-induced less lipid peroxidation. Differences in lesion area did not correlate with any significant alterations in serum lipid levels. The exercise load used in the current study did not affect energy metabolism efficacies in the hearts. Conclusion: Exercise training, in which the load did not affect energy metabolism efficacy of the heart, suppressed atherosclerosis by antioxidant effects via the vascular NO system. [Copyright &y& Elsevier]

Combination chemotherapy with pertuzumab, trastuzumab, and docetaxel is recommended as the first-line treatment for patients with HER2-positive unresectable or metastatic breast cancer. We report 2 cases of unresectable breast cancer for which pertuzumab, trastuzumab, and docetaxel therapy was effective. Case 1: A woman in her 40s was diagnosed with TxN3aM0, Stage ⅢC, HER2-positive, hormone receptor-positive advanced breast cancer. After administration of 6 courses of pertuzumab, trastuzumab, and docetaxel therapy, she underwent surgery(Bt+Ax[Ⅱ]). Histopathological examination revealed that chemotherapy effect was Grade 3. Case 2: A woman in her 60s was diagnosed with de novo Stage Ⅳ, HER2- positive, hormone receptor-negative breast cancer. She was administered 8 courses of pertuzumab, trastuzumab, and docetaxel therapy as the third-line treatment, because she initially refused treatment. Thereafter, she underwent surgery(Bt+Ax [Ⅰ]). In both cases, histopathological examination revealed complete response after chemotherapy. Thus, combination therapy of pertuzumab and trastuzumab may improve the prognosis in patients with HER2-positive breast cancer.

Objectives: Immunoglobulin treatment is known to suppress atherosclerosis in apolipoprotein E-deficient mice. In addition, immunoglobulin inhibits atherosclerosis via the Fc receptors. However, the effect of immunoglobulin treatment at the advanced stage of atherosclerosis is still unclear. This study examined the effects of immunoglobulin on apolipoprotein E-deficient mice at the advanced stage of the disease., Methods: Atherosclerosis was induced in mice fed a high-fat diet containing 0.3% cholesterol. After confirming the presence of atherosclerotic lesions at 11 weeks, mice were intraperitoneally treated with injections of either intact type of immunoglobulin (1 g/kg/day) or F (ab') 2 fragments of immunoglobulin (1 g/kg/day) on alternate days over 4 weeks. Oil red-O staining and immunohistochemical staining with CD4+ cells were performed of the aorta, and atherosclerotic lesions was evaluated and compared between the groups., Results: Fatty streak lesion was significantly suppressed by intact immunoglobulin compared with saline, and inflammatory cell infiltration and expression of CD4+ cells were less in mice treated with intact immunoglobulin compared with the control., Conclusions: Immunoglobulin treatment even at the advanced stage of atherosclerosis suppressed the development of fatty lesions and may stabilize atherosclerotic plaques by inhibiting inflammatory cell expression. Immunoglobulin suppression of atherosclerosis was confirmed to act via the Fc receptors.