3,654 research outputs found
Non-perturbative Dynamical Decoupling Control: A Spin Chain Model
This paper considers a spin chain model by numerically solving the exact
model to explore the non-perturbative dynamical decoupling regime, where an
important issue arises recently (J. Jing, L.-A. Wu, J. Q. You and T. Yu,
arXiv:1202.5056.). Our study has revealed a few universal features of
non-perturbative dynamical control irrespective of the types of environments
and system-environment couplings. We have shown that, for the spin chain model,
there is a threshold and a large pulse parameter region where the effective
dynamical control can be implemented, in contrast to the perturbative
decoupling schemes where the permissible parameters are represented by a point
or converge to a very small subset in the large parameter region admitted by
our non-perturbative approach. An important implication of the non-perturbative
approach is its flexibility in implementing the dynamical control scheme in a
experimental setup. Our findings have exhibited several interesting features of
the non-perturbative regimes such as the chain-size independence, pulse
strength upper-bound, noncontinuous valid parameter regions, etc. Furthermore,
we find that our non-perturbative scheme is robust against randomness in model
fabrication and time-dependent random noise
The peculiar filamentary HI structure of NGC 6145
In this paper, we report the peculiar HI morphology of the cluster spiral
galaxy NGC 6145, which has a 150 kpc HI filament on one side that is nearly
parallel to its major axis. This filament is made up of several HI clouds and
the diffuse HI gas between them, with no optical counterparts. We compare its
HI distribution with other one-sided HI distributions in the literature, and
find that the overall HI distribution is very different from the typical tidal
and ram-pressure stripped HI shape, and its morphology is inconsistent with
being a pure accretion event. Only about 30% of the total HI gas is anchored on
the stellar disk, while most of HI gas forms the filament in the west. At a
projected distance of 122 kpc, we find a massive elliptical companion (NGC
6146) with extended radio emission, whose axis points to an HI gap in NGC 6145.
The velocity of the HI filament shows an overall light-of- sight motion of 80
to 180 km/s with respect to NGC 6145. Using the long-slit spectra of NGC 6145
along its major stellar axis, we find that some outer regions show enhanced
star formation, while in contrast, almost no star formation activities are
found in its center (less than 2 kpc). Pure accretion, tidal or ram-pressure
stripping is not likely to produce the observed HI filament. An alternative
explanation is the jet-stripping from NGC 6146, although direct evidence for a
jet-cold gas interaction has not been found.Comment: 12 pages, 6 figures; Accepted for publication in A
Rutin has anti-asthmatic effects in an ovalbumin-induced asthmatic mouse model
Purpose: To investigate the anti-asthmatic effects of the flavonoid rutin in an ovalbumin (OVA)-induced asthmatic mouse model.Methods: Asthma was induced by OVA induction. Effects of rutin (25–100 mg/kg BW) on interleukins (IL)-4, IL-5, and IL-13 and interferon (IFN)-γ in bronchoalveolar lavage fluid (BALF) and serum OVAspecific IgE levels were assessed by enzyme linked immunosorbent assay (ELISA). Airway hyperresponsiveness (AHR) was measured by determining lung compliance and airway resistance. Expression levels of p-I-κBα, p-NF-κB p65, TNF-α, and Foxp3 were also assessed. The CD4+ CD25+ Foxp3+ T regulatory cell population was determined by flow cytometry.Results: Rutin significantly (p < 0.05) decreased Th2 cytokines (IL-4, IL-5, IL-13), whereas it enhanced IFN-γ levels in BALF. Decreased OVA-specific serum IgE was also observed with improved lung histology. Rutin was effective in reducing AHR and regulating the expression levels of p-I-κBα, p-NF-κB p65, and TNF α, and also increased the CD4+ CD25+ Foxp3+ Treg cell population and Foxp3 mRNA and protein levels.Conclusion: Rutin effectively suppresses OVA-induced asthma and improves airway function by suppressing inflammatory mediators and inflammatory cell infiltration.Keywords: Asthma, CD4+ CD25+, Cytokines, Inflammation, Ovalbumin, Rutin, Protein level
Progressive amorphization of GeSbTe phase-change material under electron beam irradiation
Fast and reversible phase transitions in chalcogenide phase-change materials
(PCMs), in particular, Ge-Sb-Te compounds, are not only of fundamental
interests, but also make PCMs based random access memory (PRAM) a leading
candidate for non-volatile memory and neuromorphic computing devices. To RESET
the memory cell, crystalline Ge-Sb-Te has to undergo phase transitions firstly
to a liquid state and then to an amorphous state, corresponding to an abrupt
change in electrical resistance. In this work, we demonstrate a progressive
amorphization process in GeSb2Te4 thin films under electron beam irradiation on
transmission electron microscope (TEM). Melting is shown to be completely
absent by the in situ TEM experiments. The progressive amorphization process
resembles closely the cumulative crystallization process that accompanies a
continuous change in electrical resistance. Our work suggests that if
displacement forces can be implemented properly, it should be possible to
emulate symmetric neuronal dynamics by using PCMs
Distribution-Based Trajectory Clustering
Trajectory clustering enables the discovery of common patterns in trajectory
data. Current methods of trajectory clustering rely on a distance measure
between two points in order to measure the dissimilarity between two
trajectories. The distance measures employed have two challenges: high
computational cost and low fidelity. Independent of the distance measure
employed, existing clustering algorithms have another challenge: either
effectiveness issues or high time complexity. In this paper, we propose to use
a recent Isolation Distributional Kernel (IDK) as the main tool to meet all
three challenges. The new IDK-based clustering algorithm, called TIDKC, makes
full use of the distributional kernel for trajectory similarity measuring and
clustering. TIDKC identifies non-linearly separable clusters with irregular
shapes and varied densities in linear time. It does not rely on random
initialisation and is robust to outliers. An extensive evaluation on 7 large
real-world trajectory datasets confirms that IDK is more effective in capturing
complex structures in trajectories than traditional and deep learning-based
distance measures. Furthermore, the proposed TIDKC has superior clustering
performance and efficiency to existing trajectory clustering algorithms
Exploring The Spatiotemporaloral Dynamics of DNA Binding and Cleavage by Restriction Endonucleaes
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