Duality, generalized Chern-Simons terms and gauge transformations in a high-dimensional curved spacetime

With two typical parent actions we have two kinds of dual worlds: i) one of which contains an electric as well as magnetic current, and ii) the other contains (generalized) Chern-Simons terms. All these fields are defined on a curved spacetime of arbitrary (odd) dimensions. A new form of gauge transformations is introduced and plays an essential role in defining the interaction with a magnetic monopole or in defining the generalized Chern-Simons terms.Comment: 10pages, Late

Dislocation Structure in Deformed Fe-35%Ni Invar Alloy Single Crystals(Metallurgy)

Dislocation structures of Fe-35%Ni invar alloy single crystals deformed at room temperature have been observed by transmission electron microscopy. The peculiar characteristics of dislocation structures are as follows : 1) most of the residual dislocations after plastic deformation are cusped screw ones in the early stage of deformation and increase in edge components with increasing strain, 2) dislocation loops exist with high density, distributed homogeneously and form weak obstacles against other dislocation motion, 3) a dislocation accumulation is observed, but does not tangle heavily. It is shown that these experimental results can be explained by the invar properties of these alloys

Exchange Effects in the Invar Hardening: Fe0.65Ni0.35Fe_{0.65}Ni_{0.35} as a test case

An increase of the critical resolved shear stress of Invar alloys (Invar hardening) with a lowering temperature is explained. The effect is caused by a growth of the exchange interaction between dangling $d$-electron states of dislocation cores and paramagnetic obstacles (e.g., Ni atoms in FeNi alloys) which occurs below the Curie temperature. The spins of the two electrons align along the magnetization due to the exchange interaction with the surrounding atoms of the ferromagnetic. The exchange interaction between the dislocations and obstacles is enhanced in Invars due to a strong growth of the magnetic moments of atoms under the action of elastic strains near the dislocation cores. Parameters characterizing the exchange interaction are determined for the case of the Fe$_{0.65}$Ni$_{0.35}$ Invar. The influence of the internal magnetic field on the dislocation detachment from the obstacles is taken into account. The obtained temperature dependence of the critical resolved shear stress in the Fe$_{0.65}$Ni$_{0.35}$ Invar agrees well with the available experimental data. Experiments facilitating a further check of the theoretical model are suggested.Comment: 8 pages, 2 figure

High glucose stimulates the expression of erythropoietin in rat glomerular epithelial cells

It has been reported that the levels of erythropoietin are associated with diabetes mellitus. Glomerular epithelial cells, located in the renal cortex, play an important role in the regulation of kidney function and hyperglycemia-induced cell loss of glomerular epithelial cells is implicated in the onset of diabetic nephropathy. This study investigated the effect of high glucose on erythropoietin and erythropoietin receptor expression in rat glomerular epithelial cells. We found that 25 mM D-glucose, but not mannitol or L-glucose, stimulated erythropoietin mRNA and protein expression in a time dependent manner (>4 h) in rat glomerular epithelial cells. In addition, 25 mM glucose, but not mannitol or L-glucose, also increased the phosphorylation of erythropoietin receptor, suggesting a role for erythropoietin receptor phosphorylation in erythropoietin synthesis. We conclude that high glucose stimulates erythropoietin production and erythropoietin receptor phosphorylation in rat glomerular epithelial cells

Growth and Perfection of Nickel and Cobalt Single Crystals Using the Floating-Zone Method(Physics)

Using the floating-zone method, Ni and Co single crystals were grown under various experimental conditions. Detailed observations of low angle boundaries or striations and of the dislocation arrangements in the grown crystals were carried out using an optical microscope. Ni single crystals grew preferentially along the direction and were striation-free. As the growth direction deviated from the , sharp striations were formed. The dislocation density in the crystals was about 10^6 cm^, which were distributed at random. Co single crystals grew along the direction and were also striation-free. As the growth direction deviated from the , many striations were formed with more complex shapes. These experimental results are discussed on the basis of the growth mechanism of crystals and of dislocation behaviour during the solidification process