33rd Aerospace Mechanisms Symposium

The proceedings of the 33rd Aerospace Mechanisms Symposium are reported. JPL hosted the conference, which was held at the Pasadena Conference and Exhibition Center, Pasadena, California, on May 19-21, 1999. Lockheed Martin Missiles and Space cosponsored the symposium. Technology areas covered include bearings and tribology; pointing, solar array and deployment mechanisms; orbiter/space station; and other mechanisms for spacecraft

Doping of Semiconductors at Nanoscale with Microwave Heating (Overview)

Incorporation of dopants efficiently in semiconductors at the nanoscale is an open challenge and is also essential to tune the conductivity. Typically, heating is a necessary step during nanomaterials’ solution growth either as pristine or doped products. Usually, conventional heating induces the diffusion of dopant atoms into host nanocrystals towards the surface at the time of doped sample growth. However, the dielectric heating by microwave irradiation minimizes this dopant diffusion problem and accelerates precursors’ reaction, which certainly improves the doping yield and reduces processing costs. The microwave radiation provides rapid and homogeneous volumetric heating due to its high penetration depth, which is crucial for the uniform distribution of dopants inside nanometer-scale semiconducting materials. This chapter discusses the effective uses of microwave heating for high-quality nanomaterials synthesis in a solution where doping is necessary to tune the electronic and optoelectronic properties for various applications

Morphological changes in diabetic kidney are associated with increased O-GlcNAcylation of cytoskeletal proteins including α-actinin 4

Abstract Purpose The objective of the present study is to identify proteins that change in the extent of the modification with O-linked N-acetylglucosamine (O-GlcNAcylation) in the kidney from diabetic model Goto-Kakizaki (GK) rats, and to discuss the relation between O-GlcNAcylation and the pathological condition in diabetes. Methods O-GlcNAcylated proteins were identified by two-dimensional gel electrophoresis, immunoblotting and peptide mass fingerprinting. The level of O-GlcNAcylation of these proteins was examined by immunoprecipitation, immunoblotting and in situ Proximity Ligation Assay (PLA). Results O-GlcNAcylated proteins that changed significantly in the degree of O-GlcNAcylation were identified as cytoskeletal proteins (α-actin, α-tubulin, α-actinin 4, myosin) and mitochondrial proteins (ATP synthase β, pyruvate carboxylase). The extent of O-GlcNAcylation of the above proteins increased in the diabetic kidney. Immunofluorescence and in situ PLA studies revealed that the levels of O-GlcNAcylation of actin, α-actinin 4 and myosin were significantly increased in the glomerulus and the proximal tubule of the diabetic kidney. Immunoelectron microscopy revealed that immunolabeling of α-actinin 4 is disturbed and increased in the foot process of podocytes of glomerulus and in the microvilli of proximal tubules. Conclusion These results suggest that changes in the O-GlcNAcylation of cytoskeletal proteins are closely associated with the morphological changes in the podocyte foot processes in the glomerulus and in microvilli of proximal tubules in the diabetic kidney. This is the first report to show that α-actinin 4 is O-GlcNAcylated. α-Actinin 4 will be a good marker protein to examine the relation between O-GlcNAcylation and diabetic nephropathy.</p