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Abstract: Objectives: To investigate the effects of benzo[a]pyrene (B[a]P), a major toxic component of cigarette smoke, on the expression of Slug and to determine the effect of B[a]P/Slug on the invasive properties of rheumatoid arthritis (RA) fibroblast-like synoviocytes (FLS). Method: The expression of Slug was measured by real-time PCR following the stimulation of FLS with different concentrations of B[a]P or EGF. The phosphorylation of the key enzymes in the signaling pathway was analyzed by western blots. Inhibitors of PI3K/Akt/mTOR pathway were used to confirm the critical pathway for Slug expression. An in vitro cell invasion assay was performed using RA FLS treated with Slug cDNA, Slug small interference RNA, or control. Results: Slug expression increased significantly following treatment with B[a]P or EGF in a dose-dependent manner. The stimulation of FLS with B[a]P or EGF induced the phosphorylation of Akt kinase, but not in ERK, JNK and p38. The Slug mRNA expression induced by B[a]P and EGF decreased significantly following the treatment with PI3K/Akt/mTOR inhibitors. Slug overexpression using Slug cDNA upregulated the invasive function of FLS, and Slug depletion using siRNA showed the opposite effect compared with the control. In addition, the stimulation with B[a]P increased the invasive function of the control siRNA-treated FLS but not in the Slug siRNA-treated FLS. Conclusion: Our data showed that B[a]P regulates the invasive properties of RA FLS through Slug expression. This mechanism may provide a novel molecular link underlying the association between smoking and increased radiographic progression in RA. [Copyright &y& Elsevier]

Abstract: The power loss of a wind turbine due to wakes from upstream turbines is significant for a wind farm. This power loss is usually about 20% of wind turbine power, and this can increase to 40% for an extreme case. Such effects decrease the annual energy production of a wind farm. Thus, it is important to predict the effect of these types of wakes so as to maximize the power output of a wind farm. In this study, we investigate a method to control the pitch angle of turbines to maximize the aerodynamic power of a wind farm. The pitch angle of each wind turbine is controlled by its own pitch schedule or feedback algorithm to optimize the power output. However, these control methods cannot consider the effects of wakes, such as velocity defects and an increase of the turbulent intensity. Thus, controlling the pitch angle of the turbine does not guarantee the maximum aerodynamic power of the wind farm, which is why a comprehensive control method considering all of the wind turbines of a wind farm is needed. The blade element momentum theory (BEM) is used for the aerodynamic analysis. In addition, in order to evaluate the wind turbine wake, the eddy viscosity model (EVM) is used. The wake is assumed to be a two-dimensional Gaussian profile determined by the thrust coefficients of the fore-located turbines and the atmospheric conditions. A genetic algorithm (GA) was applied to calculate the optimal power. The results show that control of the pitch angle can maximize the power output of the wind farm. [Copyright &y& Elsevier]

Objectives: Spondyloarthritis (SpA) encompasses a group of disorders including ankylosing spondylitis, psoriatic arthritis, reactive arthritis, and enteropathic arthritis. SpA pathogenesis is still not well understood. Animal models are important for studying disease mechanisms and identifying new therapeutic agents. Recently, a β-glucan-induced SKG mouse was used as an animal model for SpA. The aim of this study was to evaluate the clinical and molecular characteristics of a zymosan-induced SKG mouse.Methods: Zymosan was injected intraperitoneally into SKG mice. Clinical arthritis scores were measured, and fluorine-18 fluorodeoxyglucose (18F-FDG) small-animal positron emission tomography/computed tomography (PET/CT) was performed to quantify joint inflammation. Histologic features of the joints, intestines, skin, and eyes were evaluated. Inflammatory cytokine and Wnt inhibitor expression was measured in mouse serum.Results: Zymosan exposure triggered SpA-like diseases in SKG mice, including peripheral arthritis, spondylitis, dactylitis, enteritis, and psoriatic skin lesions. 18F-FDG uptake was significantly higher in the zymosan-treated mice compared with controls. The expression of tumor necrosis factor α, interleukin (IL)-6, and Dickkopf-1 increased significantly, while IL-4 and sclerostin expression decreased significantly in zymosan-induced mice compared with control mice.Conclusions: Zymosan-induced SKG mice developed articular and extra-articular features as well as molecular changes that resembled those of human SpA. These findings suggest that the zymosan-induced SKG mouse is a good animal model to reflect the complex features of human SpA. [ABSTRACT FROM AUTHOR]

Although many full waveform inversion methods have been developed to construct velocity models of subsurface, various approaches have been presented to obtain an inversion result with long-wavelength features even though seismic data lacking low-frequency components were used. In this study, a new full waveform inversion algorithm was proposed to recover a long-wavelength velocity model that reflects the inherent characteristics of each frequency component of seismic data using a single-frequency component decomposed from the spectrogram. We utilized the wavelet transform method to obtain the spectrogram, and the decomposed signal from the spectrogram was used as transformed data. The Gauss–Newton method with the diagonal elements of an approximate Hessian matrix was used to update the model parameters at each iteration. Based on the results of time–frequency analysis in the spectrogram, numerical tests with some decomposed frequency components were performed using a modified SEG/EAGE salt dome (A–A′) line to demonstrate the feasibility of the proposed inversion algorithm. This demonstrated that a reasonable inverted velocity model with long-wavelength structures can be obtained using a single frequency component. It was also confirmed that when strong noise occurs in part of the frequency band, it is feasible to obtain a long-wavelength velocity model from the noise data with a frequency component that is less affected by the noise. Finally, it was confirmed that the results obtained from the spectrogram inversion can be used as an initial velocity model in conventional inversion methods. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this study is to measure α-defensin-1 expression in the peripheral blood of patients with Behçet's disease (BD) and healthy control (HC) and to assess the association between α-defensin-1 expression and clinical features of BD.Methods: Our patients fulfilled the diagnostic criteria of the international BD study group. ELISA and real-time PCR were performed to measure α-defensin-1 protein level in the sera and α-defensin-1 mRNA level in peripheral blood mononuclear cells (PBMC), respectively.Results: The α-defensin-1 mRNA expression was significantly higher in BD patients (n=59) than HC (n=34) (0.49±0.10 vs. 0.19±0.45, P=0.03). The level of α-defensin-1 mRNA and protein was significantly higher in active patients than inactive patients (n=15, 0.91±0.28 vs. n=44, 0.35±0.09, P<0.001 and n=21, 7.50±2.14ng/ml vs. n=50, 3.32±0.96ng/ml, P=0.001, respectively). The level of α-defensin-1 mRNA was significant higher in patients with arthritis (n=20) than those without arthritis (n=39).Conclusion: α-defensin-1 mRNA and protein levels are significantly increased in BD patients, especially in active BD patients. Furthermore, α-defensin-1 mRNA is over-expressed in the PBMC of BD patients with arthritis. The present study suggests that α-defensin-1 may be involved in the pathogenesis of BD and can be used as valuable biologic marker for estimation of disease activity in BD. [ABSTRACT FROM AUTHOR]