[en] TiO₂ films with potential for dye-sensitized solar cells were deposited by using reactive medium frequency magnetron sputtering deposition. Two groups of films were prepared respectively by changing the oblique angle of the substrate and the total pressure. Scanning electron microscopy and spectroscopic ellipsometry measurements were used to characterize the deposited TiO₂ films. The result showed that increasing the oblique angle and increasing the total pressure were both effective in increasing the porosity of the TiO₂ films.

[en] Recently, oxidative stress is involved in hepatofibrogenesis. Matrix metalloproteinase-2 (MMP-2) is required for activation of hepatic stellate cells (HSCs) in response to reactive oxygen species (ROS). This study was designed to explore the hypothesis that the inhibitory effect of rosmarinic acid (RA) on HSCs activation might mainly result from its antioxidant capability by increasing the synthesis of glutathione (GSH) involved in nuclear factor kappa B (NF-κB)-dependent inhibition of MMP-2 activity. Here, we demonstrate that RA reverses activated HSCs to quiescent cells. Concomitantly, RA inhibits MMP-2 activity. RNA interference-imposed knockdown of NF-κB abolished down-regulation of MMP-2 by RA. RA-mediated inactivation of NF-κB could be blocked by the diphenyleneiodonium chloride (DPI; a ROS inhibitor). Conversely, transfection of dominant-negative (DN) mutant of extracellular signal-regulated kinases 2 (ERK2), c-Jun N-terminal kinase 1 (JNK1), or p38α kinase had no such effect. Simultaneously, RA suppresses ROS generation and lipid peroxidation (LPO) whereas increases cellular GSH in HSC-T6 cells. Furthermore, RA significantly increased antioxidant response element (ARE)-mediated luciferase activity, nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2) and catalytic subunits from glutamate cysteine ligase (GCLc) expression, but not modulatory subunits from GCL (GCLm). RA-mediated up-regulation of GClc is inhibited by the shRNA-induced Nrf2 knockdown. The knocking down of Nrf2 or buthionine sulfoximine (a GCL inhibitor) abolished RA-mediated inhibition of ROS. Collectively, these results provide novel insights into the mechanisms of RA as an antifibrogenic candidate in the prevention and treatment of liver fibrosis. - Highlights: • RA reverses activated HSCs to quiescent cells. • RA suppresses MMP-2 activity through a NF-κB-dependent pathway. • Inhibition of oxidative stress by RA is dependent on nuclear translocation of Nrf2. • RA-mediated down-regulation of MMP-2 was ROS-dependent.

[en] Branching ratios of cross section for pp-bar annihilation into two various meson processes are calculated by using the one-gluon-exchange quark-antiquark annihilation potential model. The results are compared with the experimental data and other theoretical values. For the processe pp-bar → π⁺π^-, the corss section as a function of incident momentum of p-bar is also studied and it is in agreement with the measured result

[en] Cross sections for the excitation of Al¹⁰⁺ ion by electron impact from ground state to 2p, 3s and 3p states have been investigated with 2-state close-coupling (2cc) and 5-state close-coupling (5cc) approximation. The indirect coupling effect has been analyzed. Comparing with the results of distorted wave approximation, it is found that the coupling effect is less important for 2s-2p transition, but for 2s-3s and 2s-3p transition it should be taken into account

[en] A generalized Bethe analytic formula for dipole-excited collision strengths is suggested, in which a cut-off k₀ in the momentum transfer, a threshold (via extrapolation) and a thrice threshold of collision strengths for each dipole-excited process are calculated quickly based on the quasi-relativistic plane wave Born (QRPB) and distorted wave (QRDW) methods respectively. The formula can be applied to moderate and low impact electron energies. As a example, dipole collision strengths and corresponding rate coefficients of Au⁵⁰⁺ are given at all impact energies, which are in agreement with that of a least-square spline method. Meanwhile the systems of k₀ in channel n₀l₀→n(l₀ + 1) are analyzed

[en] In this work, we propose a statistically weighted simultaneous algebraic reconstruction technique (wSART) for computed tomography (CT) imaging. The wSART algorithm is a generalization of the conventional simultaneous algebraic reconstruction technique (SART) which accounts for the statistical information of the measured projection data. We validate our proposed algorithm by use of real phantom data collected from Aquilion ONETM scanner. Our preliminary results showed that the wSART algorithm can efficiently suppress the streak artifacts induced by photon starvation. (orig.)

[en] Electron-impact excitation collision strength Ω(nl-n'l'), (3≤n≤7, 4≤n'≤7) among configuration-average levels for the Cu-like Ions Ba, Nd, Gd, Yb, Au, Pb have been calculated systematically using the quasi-relativistic distorted-wave methods. In addition, the collision strength in high energy limit have been calculated. The data for the collision strength or thermally averaged rate coefficient over the entire range of energy or temperature have been evaluated by a least-squares spline fitting procedure. As a result, the collision strength with arbitrary electron energy and rate coefficient with arbitrary temperature can be determined by ten parameters. Some scaled rules have also been given

[en] The development of accurate and efficient algorithms for image reconstruction from helical cone-beam projections remains a subject of active research. In the last few years, a number of quasi-exact and exact algorithms have been developed. Among them, the Katsevich algorithms are of filtered backprojection type and thus possess computational advantages over other existing exact algorithms. In this work, we propose an alternative approach to reconstructing exactly an image from helical cone-beam projections. Based on this approach, we develop an algorithm that requires less data than do the existing quasi-exact and exact algorithms, including the Katsevich algorithms. Our proposed algorithm is also of filtered backprojection type with one-dimensional filtering performed along a PI-line in image space. Therefore, it is (at least) computationally as efficient as the Katsevich algorithms. We have performed a preliminary numerical study to demonstrate and validate the proposed algorithm using computer-simulation data. The implication of the proposed approach and algorithm appears to be significant in that they can naturally address the long object problem as well as the super-short scan problem and, most importantly, in that they provide the opportunity to reconstruct images within any selected region of interest from minimum data, allowing the use of detector with a reduced size, the selection of a minimum number of rotation angles and thus the reduction of radiation dose delivered to the imaged subject

[en] The Hatree-Fock relativistic (HFR) method has been used to calculate the cross section of photoionization and the Bethe coefficient of all charge states of Al. The latter, which dominates the cross section of electron-impact ionization at high energy region, is also related to the cross section of photoionization. Variation of the cross section of different charge states is discussed. The data reported here is in good agreement with that of Verner et al. obtained with Hatree-Dirac-Slater method

[en] The DWBE method has been used to calculate the cross sections and of electron impact ionization of Al^q+ (q = 1-12). The authors have related the scaled cross sections to the Bethe coefficients at high energy regime. The latter can be obtained by integral of cross section of photoionization. These cross sections are then fit to obtain corresponding rate coefficients. According to the calculations, the scaled cross sections vary slowly as the charge state change. Authors' results are in good agreement with those of experiment and other theoretical calculations