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The growth of GaSb on GaAs is of interest for a variety of scientific and technological applications. Some evidence suggests that low threading dislocation density GaSb can be grown directly on GaAs through arrays of periodic edge misfit dislocations. However, significant conflicting data also exist. This work seeks to clarify the question through transmission electron microscopy analysis of GaSb grown on GaAs. The results of this work show that the single strategy of direct growth of GaSb on GaAs results in dislocation densities too high for devices. A secondary strategy of dislocation filtering layers is introduced to further reduce threading dislocations. Dislocation filtering layers are shown to be effective at bending threading dislocations at strained interfaces. Advanced analytical methods are employed to assist in developing a unique view of the dislocation filtering layer. These results enable a comprehensive evaluation of dislocation behavior extending the scientific understanding of this complex interface.

C57BL/6 mice with dilated cardiomyopathy (DCM) were randomly divided to receive placebo or pitavastatin at a dose of 1 or 3 mg kg–1 d–1. After 8 weeks of treatment, mice with dilated cardiomyopathy developed serious cardiac dysfunction characterized by significantly enhanced left ventricular end-diastolic diameter (LVIDd), decreased left ventricular ejection fraction (LVEF) as well as left ventricular short axis fractional shortening (LVFS), accompanied with enlarged cardiomyocytes, and increased plasma levels of N-terminal pro-B type natriuretic peptide (NT-proBNP) and plasma angiotensin II (AngII) concentration. Moreover, myocardium sarcoplasmic reticulum Ca2+ pump (SERCA-2) activity was decreased. The ratio of phosphorylated phospholamban (PLB) to total PLB decreased significantly with the down-regulation of SERCA-2a and ryanodine receptor (RyR2) expression. Pitavastatin was found to ameliorate the cardiac dysfunction in mice with dilated cardiomyopathy by reversing the changes of the ratios of phosphorylated PLB to total PLB, SERCA-2a and RyR2 via reducing the plasma AngII concentration, and the expressions of myocardium angiotensin II type 1 receptor (AT1R) and protein kinase C (PKC)β2. The possible underlying mechanism might be the regulation of myocardial AT1R-PKCβ2-Ca2+ handling proteins.