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Femtosecond laser-interference crystallization (FLIC) was used to form a spatially periodic magnetic structure by selectively crystallizing a paramagnetic amorphous Co2MnSi thin film. Regularly spaced alternating lines of polycrystalline and microcrystalline regions with a periodicity of 2 μm were produced by FLIC. The crystalline region composed of ∼100-nm-sized grains contained a nonequilibrium ferromagnetic phase intermixed with β-Mn. The areas between the crystallized lines also received sufficient energy, crystallizing into a microcrystalline state with its grain size ranging from 1 to 5 nm. The magnetic force microscopy of the samples clearly revealed the one-dimensional periodic magnetic domains resulting from the modulated microstructure. [ABSTRACT FROM AUTHOR]

PURPOSE: To evaluate long-term effects of multiple intravitreal antivascular endothelial growth factor (VEGF) injections on intraocular pressure (IOP) in eyes with neovascular age-related macular degeneration (AMD) or retinal vein occlusion (RVO). DESIGN: Retrospective cohort study. METHODS: This study enrolled patients who underwent multiple (more than 3) intravitreal anti-VEGF injections and who were followed for more than 12 months after their last injection. IOP elevation was defined as an increase of 5 mm Hg over the baseline measurement on 2 consecutive visits. The frequency of IOP elevation was determined. A hazard ratio of each putative risk factor for IOP elevation was calculated using the Cox proportional hazard model for all participants, incorporating underlying disease as a covariate, as well as for each cohort. RESULTS: Included in the analysis were 629 eyes with neovascular AMD and 95 eyes with RVO. Twenty eyes with neovascular AMD (3.0%) and 7 eyes with RVO (7.4%) experienced IOP elevation after multiple anti- VEGF injections, with an overall incidence of 3.7%. In the Cox proportional hazard analysis of total participants, a diagnosis ofRVO(3.424, P[0.005), a history of glaucoma (8.441, P[0.001), and low baseline IOP (0.865, P[0.040) were all significant risk factors for IOP elevation after multiple anti-VEGF injections. CONCLUSION: A history of multiple intravitreal anti- VEGF injections was not a significant risk factor for IOP elevation in our study. IOP elevation was more common in eyes with RVO than with AMD after anti-VEGF injection. [ABSTRACT FROM AUTHOR]

Structural changes of and the interactions between organic materials in liquid crystal display panel after UV exposure were systematically investigated using FT-IR, XPS, AFM, and LC-ESI-MS. When the photo-curing of the sealant was imperfect during the assembly of LCD panel, both the components in the sealant such as UV-initiator contaminated the LC's and the stray UV light oxidized the benzene rings and other chemical bonds in the polymer backbone of the alignment layer. This resulting contamination of LC's and degradation of the alignment layer could disturb the pretilt angle of the VA-mode LC's and cause the display defects on the LCD panel. In this regard, careful control of the photo-curing of the sealant will be required for precise alignment of the LCD panel and better performance of the display. [ABSTRACT FROM AUTHOR]

The purpose of this study was to predict the acoustic performance of a fully lined rectangular plenum chamber having inlet and outlet ports at arbitrary locations. Because no exact analytic solution exists for this reactive-resistive silencer configuration, numerical methods are only available for a three-dimensional analysis. The lined plenum chamber was modeled as a piston-driven rectangular tube without mean flow and the acoustic pressure in the lined chamber was obtained by superposing the acoustic pressures due to each harmonically fluctuating piston. Air pore and skeleton material of the porous liner was reduced to an equivalent medium; thus, its acoustic characteristic was given by bulk-reacting liner properties. A single weak variational statement, which satisfies the conditions of the oscillating piston and all necessary boundary conditions, was developed. The Rayleigh-Ritz method was employed as the numerical scheme for the derived variational statement. Using a transfer matrix and measured material properties, all possible types of lined plenum chambers were tested. Computed results were compared with the predicted transmission loss by the locally reacting liner model and experimental results. Transmission loss predicted by the Rayleigh–Ritz method using the bulk-reacting liner model agreed well with the measured one. [ABSTRACT FROM AUTHOR]

A problematic coordination behavior of highly hygroscopic FeCl[sub 3] in DMF solution was studied. From the compositional and structural analyses for the adduct of FeCl[sub 3]/DMF using various techniques such as FTIR, elemental analysis, UV/vis, XPS, and TGA/DTG, it was found that the iron cation exists in the form of an Fe[sup 3+] cation and coordinates via the carbonyl oxygen atom of amide bond in DMF. The analyses of both FT-IR and XPS C 1s spectra for the adduct revealed that 2.1 molecules of DMF coordinate with a more electron-deficient Fe[sup 3+]; otherwise 1.2 molecules of DMF coordinated with a relatively electron-rich Fe[sup 3+]. The Cl 2p spectrum indicated that the electron-deficient Fe[sup 3+] coordinated with two chlorine ions and the electron-rich Fe[sup 3+] with four chlorines so that the chemical formula of the adduct is of [FeCI[sub 2](DMF)[sub 1.2](H[sub 2]O)[sub 2.7]][sup +][FeCI[sub 4](DMF)[sub 2.1]][sup -]. The water molecules in the adduct were found chemisorbed rather than physisorbed, with a singular binding energy. [ABSTRACT FROM AUTHOR]

Enterotoxigenic Bacteroides fragilis (ETBF) produces a ~20-kDa heat-labile enterotoxin (BFT) that plays an essential role in mucosal inflammation. Although a variety of inflammatory cells is found at ETBF-infected sites, little is known about leukocyte adhesion in response to BFT stimulation. We investigated whether BFT affected the expression of ICAM-1 and monocytic adhesion to endothelial cells (ECs). Stimulation of HUVECs and rat aortic ECs with BFT resulted in the induction of ICAM-1 expression. Upregulation of ICAM-1 was dependent on the activation of IκB kinase (IKK) and NF-κB signaling. In contrast, suppression of AP-1 did not affect ICAM-1 expression in BFT-stimulated cells. Suppression of NF-κB activity in HUVECs significantly reduced monocytic adhesion, indicating that ICAM-1 expression is indispensable for BFT-induced adhesion of monocytes to the endothelium. Inhibition of JNK resulted in a significant attenuation of BFT-induced ICAM-1 expression in ECs. Moreover, inhibition of aldose reductase significantly reduced JNK-dependent IKK/NF-κB activation, ICAM-1 expression, and adhesion of monocytes to HUVECs. These results suggest that a signaling pathway involving aldose reductase, JNK, IKK, and NF-κB is required for ICAM-1 induction in ECs exposed to BFT, and may be involved in the leukocyte-adhesion cascade following infection with ETBF. [ABSTRACT FROM AUTHOR]

Clostridium difficile toxin A causes acute colitis associated with intense infiltrating neutrophils. Although dendritic cells (DCs) play an important role in the regulation of inflammation, little is known about the effects of toxin A on the maturation and neutrophil-attracting chemokine expression in DCs. This study investigated whether C. difficile toxin A could influence the maturation of mouse bone-marrow-derived DCs and chemokine CXCL2 expression. Toxin A increased the DC maturation which was closely related to CXCL2 upregulation. Concurrently, toxin A activated the signals of p65/p50 nuclear factor kappa B (NF-κB) heterodimers and phospho-IκB kinase (IKK) in DCs. The increased DC maturation, CXCL2 expression, and neutrophil chemoattraction were significantly downregulated in the NF-κB knockout mice. In addition, toxin A activated the phosphorylated signals of mitogen-activated protein kinases (MAPKs), such as ERK, p38, and JNK. Of all three MAPK signals, p38 MAPK was significantly related to DC maturation. Thus, suppression of p38 activity using SB203580 and siRNA transfection resulted in the significant reduction of IKK activity, DC maturation, and CXCL2 upregulation by toxin A. These results suggest that p38 MAPK may lead to the activation of IKK and NF-κB signaling, resulting in enhanced DC maturation and CXCL2 expression in response to C. difficile toxin A stimulation. [ABSTRACT FROM AUTHOR]

Clostridium difficile toxin A causes acute colitis associated with intense infiltration of neutrophils. Although C. difficile toxin A is known to induce nuclear factor-kappaB-mediated chemokine expression in intestinal epithelial cells, little is known about its effect on the regulation of activator protein-1 (AP-1) by mitogen-activated protein kinase (MAPK). In the present study, we investigated whether the MAPK and AP-1 signaling pathway is involved in interleukin (IL)-8 expression and enteric inflammation in response to stimulation with toxin A. Toxin A activated MAPK and AP-1 composed of c -Jun/c- Fos heterodimers in primary intestinal epithelial cells and HT-29 cell lines. Transfection with mutant genes for Ras, c -Jun, p38, or c -Jun N-terminal kinase (JNK) significantly inhibited C. difficile toxin A-induced activation of AP-1 and expression of IL-8 in HT-29 cell lines. Furthermore, the p38 inhibitor SB203580 attenuated toxin A-induced inflammation in vivo in the mouse ileum, evidenced by a significant decrease in neutrophil infiltration, villous destruction, and mucosal congestion. Our results suggest that the Ras/MAPK cascade acts as the upstream signaling for AP-1 activation and IL-8 expression in toxin A-stimulated intestinal epithelial cells and may be involved in the development of enteritis after infection with toxin A-producing C. difficile. [ABSTRACT FROM AUTHOR]