Neuroprotective Effects of Astaxanthin in Oxygen-Glucose Deprivation in SH-SY5Y Cells and Global Cerebral Ischemia in Rat

Astaxanthin (ATX), a naturally occurring carotenoid pigment, is a powerful biological antioxidant. In the present study, we investigated whether ATX pharmacologically offers neuroprotection against oxidative stress by cerebral ischemia. We found that the neuroprotective efficacy of ATX at the dose of 30 mg/kg (n = 8) was 59.5% compared with the control group (n = 3). In order to make clear the mechanism of ATX neuroprotection, the up-regulation inducible nitric oxide synthase (iNOS) and heat shock proteins (HSPs) together with the oxygen glucose deprivation (OGD) in SH-SY5Y cells were also investigated. The induction of various factors involved in oxidative stress processes such as iNOS was suppressed by the treatment of ATX at 25 and 50 µM after OGD-induced oxidative stress. In addition, Western blots showed that ATX elevated of heme oxygenase-1 (HO-1; Hsp32) and Hsp70 protein levels in in vitro. These results suggest that the neuroprotective effects of ATX were related to anti-oxidant activities in global ischemia

Global Characteristics of the Correlation and Time Lag Between Solar and Ionospheric Parameters in the 27-day Period

The 27-day variations of topside ionosphere are investigated using the in-situ electron density measurements from the CHAMP planar Langmuir probe and GRACE K-band ranging system. As the two satellite systems orbit at the altitudes of approx. 370 km and approx. 480 km, respectively, the satellite data sets are greatly valuable for examining the electron density variations in the vicinity of F2-peak. In a 27-day period, the electron density measurements from the satellites are in good agreements with the solar flux, except during the solar minimum period. The time delays are mostly 1-2 day and represent the hemispherical asymmetry. The globally-estimated spatial patterns of the correlation between solar flux and in-situ satellite measurements show poor correlations in the (magnetic) equatorial region, which are not found from the ground measurements of vertically-integrated electron content. We suggest that the most plausible cause for the poor correlation is the vertical movement of ionization due to atmospheric dynamic processes that is not controlled by the solar extreme ultraviolet radiation

Resonance of Domain Wall in a Ferromagnetic Nanostrip: Relation Between Distortion and Velocity

The resonance of the magnetic domain wall under the applied field amplifies its velocity compared to the one-dimensional model. To quantify the amplification, we define the distortion variation rate of the domain wall that can represent how fast and severely the wall shape is variated. Introducing that rate gives a way to bring the resonance into the one-dimensional domain wall dynamics model. We obtain the dissipated energy and domain wall velocity amplification by calculating the distortion variation rate. The relationship between velocity and distortion variation rate agrees well with micromagnetic simulation.Comment: 15 pages, 4 figure

State Complexity of Regular Tree Languages for Tree Matching

We study the state complexity of regular tree languages for tree matching problem. Given a tree t and a set of pattern trees L, we can decide whether or not there exists a subtree occurrence of trees in L from the tree t by considering the new language L′ which accepts all trees containing trees in L as subtrees. We consider the case when we are given a set of pattern trees as a regular tree language and investigate the state complexity. Based on the sequential and parallel tree concatenation, we define three types of tree languages for deciding the existence of different types of subtree occurrences. We also study the deterministic top-down state complexity of path-closed languages for the same problem.</jats:p

Physical Origin and Generic Control of Magnonic Band Gaps of Dipole-Exchange Spin Waves in Width-Modulated-Nanostrip Waveguides

We report, for the first time, on a novel planar structure of magnonic-crystal waveguides, made of a single magnetic material, in which the allowed and forbidden bands of propagating dipole-exchange spin-waves can be manipulated by the periodic modulation of different widths in thin-film nanostrips. The origin of the presence of several magnonic wide band gaps and the crucial parameters for controlling those band gaps of the order of ~10 GHz are found by micromagnetic numerical and analytical calculations. This work can offer a route to the potential application to broad-band spin-wave filters in the GHz frequency range.Comment: 24 pages, 8 figure

Ice Velocity Mapping of Ross Ice Shelf, Antarctica by Matching Surface Undulations Measured by Icesat Laser Altimetry

We present a novel method for estimating the surface horizontal velocity on ice shelves using laser altimetrydata from the Ice Cloud and land Elevation Satellite (ICESat; 20032009). The method matches undulations measured at crossover points between successive campaigns