23 research outputs found
Expulsion of Magnetic Flux Lines from the Growing Superconducting Core of a Magnetized Quark Star
The expulsion of magnetic flux lines from a growing superconducting core of a
quark star has been investigated. The idea of impurity diffusion in molten
alloys and an identical mechanism of baryon number transport from hot
quark-gluon-plasma phase to hadronic phase during quark-hadron phase transition
in the early universe, micro-second after big bang has been used. The
possibility of Mullins-Sekerka normal-superconducting interface instability has
also been studied.Comment: Thoroughly revised version. Accepted for Astrophysics & Space Scienc
On the Low Surface Magnetic Field Structure of Quark Stars
Following some of the recent articles on hole super-conductivity and related
phenomena by Hirsch \cite{H1,H2,H3}, a simple model is proposed to explain the
observed low surface magnetic field of the expected quark stars. It is argued
that the diamagnetic moments of the electrons circulating in the electro-sphere
induce a magnetic field, which forces the existing quark star magnetic flux
density to become dilute. We have also analysed the instability of
normal-superconducting interface due to excess accumulation of magnetic flux
lines, assuming an extremely slow growth of superconducting phase through a
first order bubble nucleation type transition.Comment: 24 pages REVTEX, one .eps figure, psfig.sty is include
What Drives Fitness Apps Usage? An Empirical Evaluation
Part 3: Creating Value through ApplicationsInternational audienceThe increased health problems associated with lack of physical activity is of great concern around the world. Mobile phone based fitness applications appear to be a cost effective promising solution for this problem. The aim of this study is to develop a research model that can broaden understanding of the factors that influence the user acceptance of mobile fitness apps. Drawing from Unified Theory of Acceptance and Use of Technology (UTAUT) and Elaboration Likelihood Model (ELM), we conceptualize the antecedents and moderating factors of fitness app use. We validate our model using field survey. Implications for research and practice are discussed
IAP antagonists target cIAP1 to induce TNFalpha-dependent apoptosis.
XIAP prevents apoptosis by binding to and inhibiting caspases, and this inhibition can be relieved by IAP antagonists, such as Smac/DIABLO. IAP antagonist compounds (IACs) have therefore been designed to inhibit XIAP to kill tumor cells. Because XIAP inhibits postmitochondrial caspases, caspase 8 inhibitors should not block killing by IACs. Instead, we show that apoptosis caused by an IAC is blocked by the caspase 8 inhibitor crmA and that IAP antagonists activate NF-kappaB signaling via inhibtion of cIAP1. In sensitive tumor lines, IAP antagonist induced NF-kappaB-stimulated production of TNFalpha that killed cells in an autocrine fashion. Inhibition of NF-kappaB reduced TNFalpha production, and blocking NF-kappaB activation or TNFalpha allowed tumor cells to survive IAC-induced apoptosis. Cells treated with an IAC, or those in which cIAP1 was deleted, became sensitive to apoptosis induced by exogenous TNFalpha, suggesting novel uses of these compounds in treating cancer