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Reasonably fabricating ordered structures of ionic polymers is very important for the development of novel functional materials. By combining the ions and liquid cry stalline polymer, we successfully designed and synthesized a series of novel combined main-chain/side-chain ionic liquid crystalline polymer (MCSC-ILCPs) containing imidazolium groups and different counter-anions, poly (2,5-bis{[6-(4-butoxy-4!-imidazolium biphenyl)hexyl]oxycarbonyl}styrene salts) poly(BImBHCS-X) with the following types of counter-anions (Br", BF4", PF6" and TFSI"). Combined technologies confirmed the chemical structures of the monomers and polymers with imidazolium cation and different counter-anions. Differential scanning calorimetry (DSC), polarized light microscopy (PLM) and one- and two-dimensional wide-angle X-ray diffraction (1D and 2D WAXD) results illustrated that the LC structures and the transitions of ordered structures depended on the nature of the counter-anion employed. The polymers with Br" and BF4" counter-anions exhibited smectic A (SmA) LC behavior below the isotropic temperature. The another one, poly(BImBHCS-TFSI) with the large volume of the TFSI" anion destroyed the packing of the LC ordered structure resulting in an amorphous structure. The photophysical properties of the polymers prepared can be adjusted by tuning the ionic interaction of the polymers by switching the counter-anion. [ABSTRACT FROM AUTHOR]

Psoralen plus ultraviolet A radiation (PUVA) therapy is a very important clinical treatment of skin diseases such as vitiligo and psoriasis, but associated with an increased risk of skin photodamage, especially photoaging. In this work, optical coherence tomography (OCT), a novel non-invasive imaging technology, was introduced to investigate in vivo the photodamage induced by PUVA qualitatively and quantitatively. Balb/c mouse dorsal skin was treated with 8-methoxypsoralen (8-MOP), and then exposed to UVA radiation. OCT images of the tissues were obtained by an OCT system with a 1310 nm central wavelength. Skin thickness and the attenuation coefficient were extracted from the OCT images to analyze the degree of injury to mouse skin. The results demonstrated that PUVA-treated skin showed an increase in skin thickness, and a reduction of attenuation coefficient in the OCT signal compared with the control groups. The data also showed good correlation with the results observed in histological sections using hematoxylin and eosin staining. In conclusion, OCT is a promising tool for photobiological studies aimed at assessing the effect of PUVA therapy in vivo. [ABSTRACT FROM AUTHOR]

Beta-induced Alfvén eigenmodes (BAEs) during strong tearing modes are investigated on the EAST tokamak systematically, and the relation between the BAE frequencies and plasma parameters such as electron density ne, ion temperature Ti, the profile of safety factor q(ρ) or the intensity of Ḃθ (the width of the magnetic island w) is given in detail during the injection of the power of lower hybrid wave (LHW) (or is also accompanied by the injection of ion cyclotron resonance frequency) comprehensively. All the conditions show that the values of BAE frequencies fBAE α (Te + 7/4Ti)1/2 are in agreement with the generalized fishbone-like dispersion relation, and the activities of the BAEs have a strong interaction with the process of magnetic reconnection. The BAEs are formed during the injection of the power of LHW, and disappear immediately when the power of LHW is turned off on the EAST tokamak. The LHW plasmas or the runaway discharge in Ohmic plasmas can increase the population of fast electrons, which plays a role in the activities of BAEs and a possible excitation mechanism for the BAEs during the strong tearing mode activities. [ABSTRACT FROM AUTHOR]

In the EAST tokamak, asymmetrical ring-like runaway electron beams with energy more than 30MeV and pitch angle about 0.1 were investigated. Those runaway beams carried about 46% of the plasma current and located around the q = 2 rational surface when m/n = 1/1 and m/n = 2/1 MHD modes existed in the plasma. Those runaway beams changed from a hollow to a filled structure during the slow oscillations in the discharge about every 0.2 s, which correlated with a large step-like jump in electron cyclotron emission (ECE) signals, a big spike-like perturbation in Mirnov signals and a large decrease in runaway energy. Between those slow oscillations with large magnitude, fast oscillations with small magnitude also existed about every 0.02 s, which correlated with a small step-like jump in ECE signals, a small spike-like perturbation in Mirnov signals, but no clear decrease in runaway energy and changes in the runaway beam structure. Resonant interactions occurred between runaway electrons and magnetohydrodynamic instabilities, which gave rise to fast pitch angle scattering processes of those resonant runaway electrons, and hence increased the synchrotron radiation. Theoretical calculations of the resonant interaction were given based on a test particle description. Synchrotron radiation of those resonant runaway electrons was increased by about 60% until the end of the resonant interaction. [ABSTRACT FROM AUTHOR]

The first plasma discharges were successfully achieved on the experimental advanced superconducting tokamak (EAST) in 2006. The sawteeth behaviours were observed by means of soft x-ray diagnostics and ECE signals in the EAST. The displacement and radius of the q = 1 surface was studied and compared with the result of equilibrium calculation. The density sawtooth oscillation was also observed by the HCN laser interferometer diagnostics. The structure of the EAST operational region was studied in detail. Plasma performance was obviously improved by the boronization and wall conditioning. It was observed that lower qa and a wider stable operating region is extended by the GDC boronization. [ABSTRACT FROM AUTHOR]

Many diabetic individuals develop anosmia but the mechanism(s) causing the dysfunction in the olfactory system is (are) unknown. Glial fibrillary acidic protein expression is reduced in diabetic retinopathy and is also reduced, with unknown consequences, in other brain regions of diabetic rats. We used immunohistochemistry and immunoblotting from untreated control and streptozotocin-induced type 1 (insulin dependent) diabetic rats to investigate main olfactory epithelial mitotic rate and glial fibrillary acidic protein expression in the lamina propria of the sensory epithelium and in the olfactory bulb. Numbers of bromodeoxyuridine-positive cells were significantly lower in the diabetic sensory epithelium compared to non-diabetic controls. Immunohistochemical observations suggested a qualitative difference in glial fibrillary acidic protein expression in both regions examined especially in the olfactory bulb external plexiform layer and the lamina propria. Immunoblot analysis confirmed that the diabetic olfactory bulb and lamina propria expressed less glial fibrillary acidic protein compared to the non-diabetic control group. The lower expression levels in the olfactory bulb external plexiform layer suggested by immunohistochemistry do not reflect a change in the number of astrocytes since the numbers of S100B(+) cells were not different between the two groups. [ABSTRACT FROM AUTHOR]

Neutron emission spectroscopy (NES) measurement aimed at providing the information on fast ions induced by auxiliary heating systems at Experimental Advanced Superconducting Tokamak (EAST), with a liquid scintillation detector is described. It is the first time that the NES diagnostics are employed to probe fast ions induced by neutral beam injection (NBI) at EAST. The time trace of the fusion neutrons, obtained by the liquid scintillation detector, was consistent with the result measured by a standard 235U fission chamber under NBI heating scenario, which verifies the performance of the detector. NUBEAM code is used to determine the fast deuteron velocity distribution using the parametrized plasma profiles as input. The pulse height spectrum of the fusion neutrons was successfully reproduced by combining the simulation of the neutron energy spectrum and the calculation of the detector response functions. The experimental data are also interpreted from a view of weight functions, which illustrate the velocity-space sensitivity of the liquid scintillation detector with a radial line of sight. The results demonstrate the capability of the liquid scintillation detector to contribute to studies on fast-ion physics at EAST. [ABSTRACT FROM AUTHOR]

In recent years, three-dimensional digital image correlation methods using a single colour camera have been reported. In this study, we propose a simplified system by employing a dichroic filter (DF) to replace the beam splitter and colour filters. The DF can be used to combine two views from different perspectives reflected by two planar mirrors and eliminate their interference. A 3CCD colour camera is then used to capture two different views simultaneously via its blue and red channels. Moreover, the measurement accuracy of the proposed method is higher since the effect of refraction is reduced. Experiments are carried out to verify the effectiveness of the proposed method. It is shown that the interference between the blue and red views is insignificant. In addition, the measurement accuracy of the proposed method is validated on the rigid body displacement. The experimental results demonstrate that the measurement accuracy of the proposed method is higher compared with the reported methods using a single colour camera. Finally, the proposed method is employed to measure the in- and out-of-plane displacements of a loaded plastic board. The re-projection errors of the proposed method are smaller than those of the reported methods using a single colour camera. [ABSTRACT FROM AUTHOR]

The concept of non-Hermitian parametric amplification was recently proposed as a means to achieve an efficient energy conversion throughout the process of nonlinear three wave mixing in the absence of phase matching. Here we investigate this effect in a waveguide coupler arrangement whose characteristics are tailored to introduce passive PT symmetry only for the idler component. By means of analytical solutions and numerical analysis, we demonstrate the utility of these novel schemes and obtain the optimal design conditions for these devices. [ABSTRACT FROM AUTHOR]

Diagnostics application of fusion reaction measurements on the Experimental Advanced Superconducting Tokamak (EAST) has been proved by fusion neutrons during deuterium plasma discharges. In lower hybrid current drive plasmas, fusion neutrons are dominant mainly due to a sufficiently low loop voltage, which suppresses the photo-neutrons caused by runaway electrons. For fixed plasma current and lower hybrid wave (LHW) power, the fusion neutron flux depends on ion density as n_{\rm i}^{(2.27\pm 0.1)} , stronger than a power of two, caused by an increased ion temperature, which is due to an increased electron and ion energy exchange by more frequent collisions at higher ion densities. The fusion neutron flux depends on I_{\rm P}^{(4.37\pm 0.18)} , at fixed LHW power and main ion density, which is mainly due to ion temperature affected by ohmic power and energy confinement time. Finally, the unchanged fusion neutron flux with LHW power indicates little variation in the main ion temperature, which is consistent with direct ion temperature measurements. This is explained by the fact that an increased energy transfer to ions by collisions is almost compensated for by less frequent collisions and decreased energy confinement time at higher LHW powers. [ABSTRACT FROM AUTHOR]