770 research outputs found
(Acetato-κO)bis(2,2′-bipyridyl-κ2 N,N′)copper(II)–ethyl sulfate–methyl sulfate (1/0.5/0.5)
In the title complex, [Cu(C2H3O2)(C10H8N2)2](CH3CH2OSO3)0.5(CH3OSO3)0.5, the CuII ion is bis-chelated by two 2,2′-bipyridine lignds and coordinated by an O atom of an acetate ligand in a CuN4O disorted square-pyramidal environment. In the structure, equal amounts of methyl sulfate and ethyl sulfate anions are disordered on the same crystallographic sites. The crystal structure is stabilized by weak intermolecular C—H⋯O interactions
Quantum and classical correlations in the one-dimensional XY model with Dzyaloshinskii-Moriya interaction
We study the effect of Dzyaloshinskii-Moriya (DM) interaction on pairwise
quantum discord, entanglement, and classical correlation in the anisotropic XY
spin-half chain. Analytical expressions for both quantum and classical
correlations are obtained from the spin-spin correlation functions. We show
that these pairwise quantities exhibit various behaviors in relation to the
relative strengths of the DM interaction, the anisotropy and the magnetic
intensity. We observe non-analyticities of the derivatives of both quantum and
classical correlations with respect to the magnetic intensity at the critical
point, with consideration of the DM interaction.Comment: 18pages, 6figure
The analysis on the single particle model of CDW
Gruner put forward a single particle model of charge-density wave, which is a
typical nonlinear differential equation, and also a mathematical model of
pendulum. This Letter analyzes the solution of equation by the rotated vector
fields theory, providing the relation between the applied field E and the
periodic solution, and the conclusion that the critical value of E for the
periodic solution is fixed in the over-damped situation. With these
conclusions, it derives the formulae of nonlinear conductivity, narrow-band
noise, which are consistent with the empirical ones given by Fleming.Comment: This is a version with a physics focus, the part with a mathematical
focus is submitted at arXiv:0807.328
Effects of Exercise on AMPK Signaling and Downstream Components to PI3K in Rat with Type 2 Diabetes
Exercise can increase skeletal muscle sensitivity to insulin, improve insulin resistance and regulate glucose homeostasis in rat models of type 2 diabetes. However, the potential mechanism remains poorly understood. In this study, we established a male Sprague-Dawley rat model of type 2 diabetes, with insulin resistance and β cell dysfunction, which was induced by a high-fat diet and low-dose streptozotocin to replicate the pathogenesis and metabolic characteristics of type 2 diabetes in humans. We also investigated the possible mechanism by which chronic and acute exercise improves metabolism, and the phosphorylation and expression of components of AMP-activated protein kinase (AMPK) and downstream components of phosphatidylinositol 3-kinase (PI3K) signaling pathways in the soleus. As a result, blood glucose, triglyceride, total cholesterol, and free fatty acid were significantly increased, whereas insulin level progressively declined in diabetic rats. Interestingly, chronic and acute exercise reduced blood glucose, increased phosphorylation and expression of AMPKα1/2 and the isoforms AMPKα1 and AMPKα2, and decreased phosphorylation and expression of AMPK substrate, acetyl CoA carboxylase (ACC). Chronic exercise upregulated phosphorylation and expression of AMPK upstream kinase, LKB1. But acute exercise only increased LKB1 expression. In particular, exercise reversed the changes in protein kinase C (PKC)ζ/λ phosphorylation, and PKCζ phosphorylation and expression. Additionally, exercise also increased protein kinase B (PKB)/Akt1, Akt2 and GLUT4 expression, but AS160 protein expression was unchanged. Chronic exercise elevated Akt (Thr(308)) and (Ser(473)) and AS160 phosphorylation. Finally, we found that exercise increased peroxisome proliferator-activated receptor-γ coactivator 1 (PGC1) mRNA expression in the soleus of diabetic rats. These results indicate that both chronic and acute exercise influence the phosphorylation and expression of components of the AMPK and downstream to PIK3 (aPKC, Akt), and improve GLUT4 trafficking in skeletal muscle. These data help explain the mechanism how exercise regulates glucose homeostasis in diabetic rats
Revisiting the quantum Szilard engine with fully quantum considerations
By considering level shifting during the insertion process we revisit the
quantum Szilard engine (QSZE) with fully quantum consideration. We derive the
general expressions of the heat absorbed from thermal bath and the total work
done to the environment by the system in a cycle with two different cyclic
strategies. We find that only the quantum information contributes to the
absorbed heat, and the classical information acts like a feedback controller
and has no direct effect on the absorbed heat. This is the first demonstration
of the different effects of quantum information and classical information for
extracting heat from the bath in the QSZE. Moreover, when the well width
or the temperature of the bath
the QSZE reduces to the classical Szilard engine (CSZE), and the total work
satisfies the relation as obtained by
Sang Wook Kim et al. [Phys. Rev. Lett. 106, 070401 (2011)] for one particle
case.Comment: 17 pages, 3 figures, to be published in Annals of Physics(NY
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