Domain walls in Born-Infeld-dilaton background

We study the dynamics of domain walls in Einstein-Born-Infeld-dilaton theory. Dilaton is non-trivially coupled with the Born-Infeld electromagnetic field. We find three different types of solutions consistent with the dynamic domain walls. For every case, the solutions have singularity. Further more, in these backgrounds, we study the dynamics of domain walls. We qualitatively plot various form of the bulk metrics and the potential encountered by the domain walls. In many cases, depending upon the value of the parameters, the domain walls show bouncing universe and also undergo inflationary phase followed by standard decelerated expansion.Comment: 18 pages,6 figures,latex, References added, Some points clarifie

Protection from experimental colitis by theaflavin-3,3'-digallate correlates with inhibition of IKK and NF-κB activation

Background and purpose: Inflammatory bowel disease (IBD) is associated with activation of nuclear factor κ B (NF-κB) involved in regulating the expression of inducible nitric oxide synthase (iNOS) and proinflammatory cytokine genes. As theaflavin-3,3'-digallate (TFDG), the most potent anti-oxidant polyphenol of black tea, down-regulates NF-κB activation, we investigated if TFDG is beneficial in colonic inflammation by suppressing iNOS and proinflammatory cytokines. Experimental approach: The in vivo efficacy of TFDG was assessed in mice with trinitrobenzene sulfonic acid (TNBS)-induced colitis. Both mRNA and protein levels of proinflammatory cytokines and iNOS were analyzed in colon tissue treated with or without TFDG. NF-κB activation was determined by electrophoretic mobility shift assay and levels of NF-κB inhibitory protein (IκBα) were analyzed by Western blotting. Key results: Oral administration of TFDG (5 mg kg-1 daily i.g.) significantly improved TNBS-induced colitis associated with decreased mRNA and protein levels of TNF-α, IL-12, IFN- and iNOS in colonic mucosa. DNA binding and Western blotting revealed increase in NF-κB activation and IκB depletion in TNBS-treated mice from Day 2 through Day 8 with a maximum at Day 4, which resulted from increased phosphorylation of IκB and higher activity of IκB kinase (IKK). Pretreatment with TFDG markedly inhibited TNBS-induced increases in nuclear localization of NF-κBα, cytosolic IKK activity and preserved IκBα in colon tissue. Conclusions and Implications: TFDG exerts protective effects in experimental colitis and inhibits production of inflammatory mediators through a mechanism that, at least in part, involves inhibition of NF-κB activation

Quantum chaos in the spectrum of operators used in Shor's algorithm

We provide compelling evidence for the presence of quantum chaos in the unitary part of Shor's factoring algorithm. In particular we analyze the spectrum of this part after proper desymmetrization and show that the fluctuations of the eigenangles as well as the distribution of the eigenvector components follow the CUE ensemble of random matrices, of relevance to quantized chaotic systems that violate time-reversal symmetry. However, as the algorithm tracks the evolution of a single state, it is possible to employ other operators, in particular it is possible that the generic quantum chaos found above becomes of a nongeneric kind such as is found in the quantum cat maps, and in toy models of the quantum bakers map.Comment: Title and paper modified to include interesting additional possibilities. Principal results unaffected. Accepted for publication in Phys. Rev. E as Rapid Com

High-k HfO2 based metal-oxide-semiconductor devices using silicon and silicon carbide semiconductor

In this paper we have calculated the flatband capacitance (CFB) for high-k dielectric material hafnia oxide (HfO2) as an insulator and silicon carbide (SiC) as a semiconductor material for metal-oxide-semiconductor (MOS) devices. We simulate the capacitance-voltage (C-V) characteristics of the MOS devices with ultrathin oxide using ATLAS, a commercially available TCAD tool from SILVACO. The tool has investigated the effect on C-V characteristics of different oxide thickness and doping concentration of SiO2 and HfO2 as insulators and Si and SiC as semiconductor based MOS devices. Excellent agreement was observed over a wide range of oxide thickness and substrate doping for the materials. The C-V characteristics of different polytype of SiC semiconductor also studied for n-type MOS devices. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/2789

The interplay between the charged Higgs and squark-gluino events at the LHC

In some extensions of the standard model with extended Higgs sectors, events from new particle production may pass the selection criteria for Higgs search in different channels at the LHC - 14 TeV and mimic Higgs signals. This intriguing possibility is illustrated by PYTHIA based simulations using several representative points in the parameter space of the minimal supersymmetric standard model (MSSM) including a point in the minimal supergravity model consistent with the Dark matter (DM) relic density data. Our simulations explore the interplay between the charged Higgs signal and typical squark-gluino events. We argue that the standard selections like the one based on the polarization properties of the $\tau$'s from charged Higgs decay, though adequate for handling the SM background, may not be very efficient in the presence of SUSY backgrounds. We then propose an alternative search strategy based on pure kinematics which sufficiently controls both the SM and the MSSM backgrounds. For charged Higgs masses ($H^{\pm}$) in the deep decoupling regime (600 GeV \lsim m_{H^{\pm}} \lsim 800 GeV) this method works well and extends the LHC reach close to 800 GeV for an integrated luminosity of 30 $fb^{-1}$ with or without the SUSY background. For a lighter charged Higgs a judicious combination of the old selections and some of the cuts proposed by us may disentangle the Higgs signal from the squark-gluino backgrounds quite effectively