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Applying semantic web services to enterprise web
Enterprise Web provides a convenient, extendable, integrated platform for information sharing and knowledge management. However, it still has many drawbacks due to complexity and increasing information glut, as well as the heterogeneity of the information processed. Research in the field of Semantic Web Services has shown the possibility of adding higher level of semantic functionality onto the top of current Enterprise Web, enhancing usability and usefulness of resource, enabling decision support and automation. This paper aims to explore the use of Semantic Web Services in Enterprise Web and discuss the Semantic Web Services (SWS) approach for designing Enterprise Web applications. A Semantic Web Service oriented model is presented, in which resources and services are described by ontology, and processed through Semantic Web Service, allowing integrated administration, interoperability and automated reasoning
Force and Mass Dynamics in Non-Newtonian Suspensions
Above a certain solid fraction, dense granular suspensions in water exhibit
non-Newtonian behavior, including impact-activated solidification. Although it
has been suggested that solidification depends on boundary interactions,
quantitative experiments on the boundary forces have not been reported. Using
high-speed video, tracer particles, and photoelastic boundaries, we determine
the impactor kinematics and the magnitude and timings of impactor-driven events
in the body and at the boundaries of cornstarch suspensions. We observe mass
shocks in the suspension during impact. The shockfront dynamics are strongly
correlated to those of the intruder. However, the total momentum associated
with this shock never approaches the initial impactor momentum. We also observe
a faster second front, associated with the propagation of pressure to the
boundaries of the suspension. The two fronts depend differently on the initial
impactor speed, , and the suspension packing fraction. The speed of the
pressure wave is at least an order of magnitude smaller than (linear)
ultrasound speeds obtained for much higher frequencies, pointing to complex
amplitude and frequency response of cornstarch suspensions to compressive
strains
Nonequilibrium Phase Transitions of Vortex Matter in Three-Dimensional Layered Superconductors
Large-scale simulations on three-dimensional (3D) frustrated anisotropic XY
model have been performed to study the nonequilibrium phase transitions of
vortex matter in weak random pinning potential in layered superconductors. The
first-order phase transition from the moving Bragg glass to the moving smectic
is clarified, based on thermodynamic quantities. A washboard noise is observed
in the moving Bragg glass in 3D simulations for the first time. It is found
that the activation of the vortex loops play the dominant role in the dynamical
melting at high drive.Comment: 3 pages,5 figure
Phonon Squeezed States Generated by Second Order Raman Scattering
We study squeezed states of phonons, which allow a reduction in the quantum
fluctuations of the atomic displacements to below the zero-point quantum noise
level of coherent phonon states. We investigate the generation of squeezed
phonon states using a second order Raman scattering process. We calculate the
expectation values and fluctuations of both the atomic displacement and the
lattice amplitude operators, as well as the effects of the phonon squeezed
states on macroscopically measurable quantities, such as changes in the
dielectric constant. These results are compared with recent experiments.Comment: 4 pages, REVTE
Analytical Solution of Electron Spin Decoherence Through Hyperfine Interaction in a Quantum Dot
We analytically solve the {\it Non-Markovian} single electron spin dynamics
due to hyperfine interaction with surrounding nuclei in a quantum dot. We use
the equation-of-motion method assisted with a large field expansion, and find
that virtual nuclear spin flip-flops mediated by the electron contribute
significantly to a complete decoherence of transverse electron spin correlation
function. Our results show that a 90% nuclear polarization can enhance the
electron spin time by almost two orders of magnitude. In the long time
limit, the electron spin correlation function has a non-exponential
decay in the presence of both polarized and unpolarized nuclei.Comment: 4 pages, 3 figure
Relativistic description of magnetic moments in nuclei with doubly closed shells plus or minus one nucleon
Using the relativistic point-coupling model with density functional PC-PK1,
the magnetic moments of the nuclei Pb, Pb, Tl and
Bi with a closed-shell core Pb are studied on the basis of
relativistic mean field (RMF) theory. The corresponding time-odd fields, the
one-pion exchange currents, and the first- and second-order corrections are
taken into account. The present relativistic results reproduce the data well.
The relative deviation between theory and experiment for these four nuclei is
6.1% for the relativistic calculations and somewhat smaller than the value of
13.2% found in earlier non-relativistic investigations. It turns out that the
meson is important for the description of magnetic moments, first by
means of one-pion exchange currents and second by the residual interaction
provided by the exchange.Comment: 11 pages, 7 figure
Tick-borne encephalitis virus induces chemokine RANTES expression via activation of IRF-3 pathway.
BACKGROUND: Tick-borne encephalitis virus (TBEV) is one of the most important flaviviruses that targets the central nervous system (CNS) and causes encephalitides in humans. Although neuroinflammatory mechanisms may contribute to brain tissue destruction, the induction pathways and potential roles of specific chemokines in TBEV-mediated neurological disease are poorly understood. METHODS: BALB/c mice were intracerebrally injected with TBEV, followed by evaluation of chemokine and cytokine profiles using protein array analysis. The virus-infected mice were treated with the CC chemokine antagonist Met-RANTES or anti-RANTES mAb to determine the role of RANTES in affecting TBEV-induced neurological disease. The underlying signaling mechanisms were delineated using RANTES promoter luciferase reporter assay, siRNA-mediated knockdown, and pharmacological inhibitors in human brain-derived cell culture models. RESULTS: In a mouse model, pathological features including marked inflammatory cell infiltrates were observed in brain sections, which correlated with a robust up-regulation of RANTES within the brain but not in peripheral tissues and sera. Antagonizing RANTES within CNS extended the survival of mice and reduced accumulation of infiltrating cells in the brain after TBEV infection. Through in vitro studies, we show that virus infection up-regulated RANTES production at both mRNA and protein levels in human brain-derived cell lines and primary progenitor-derived astrocytes. Furthermore, IRF-3 pathway appeared to be essential for TBEV-induced RANTES production. Site mutation of an IRF-3-binding motif abrogated the RANTES promoter activity in virus-infected brain cells. Moreover, IRF-3 was activated upon TBEV infection as evidenced by phosphorylation of TBK1 and IRF-3, while blockade of IRF-3 activation drastically reduced virus-induced RANTES expression. CONCLUSIONS: Our findings together provide insights into the molecular mechanism underlying RANTES production induced by TBEV, highlighting its potential importance in the process of neuroinflammatory responses to TBEV infection
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