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ECG helps in diagnosing heart disease by recording heart activity. During long-term measurements, data loss occurs due to sensor detachment. Therefore, research into the reconstruction of missing ECG data is essential. However, ECG requires user participation and cannot be used for continuous heart monitoring. Continuous monitoring of PPG signals is conversely low-cost and easy to carry out. In this study, a deep neural network model is proposed for the reconstruction of missing ECG signals using PPG data. This model is an end-to-end deep learning neural network utilizing WNet architecture as a basis, on which a bidirectional long short-term memory network is added in establishing a second model. The performance of both models is verified using 146 records from the MIMIC III matched subset. Compared with the reference, the ECG reconstructed using the proposed model has a Pearson's correlation coefficient of 0.851, root mean square error (RMSE) of 0.075, percentage root mean square difference (PRD) of 5.452, and a Fréchet distance (FD) of 0.302. The experimental results demonstrate that it is feasible to reconstruct missing ECG signals from PPG. [ABSTRACT FROM AUTHOR]

Objective: To analyze the changes in the levels of bone metabolism markers related to sacroiliac joint (SIJ) inflammation in patients with axial spondyloarthritis (axSpA) after treatment with imrecoxib and celecoxib and evaluate their relationship with clinical efficacy. Methods: A total of 120 patients with axSpA with at least 2 magnetic resonance imaging (MRI) SIJ scans during a 12-week follow-up were enrolled. The levels of bone metabolism markers, including dickkopf-1(DKK-1), sclerostin, vascular endothelial growth factor (VEGF), bone morphogenetic protein-2 (BMP-2), osteoprotegerin (OPG), noggin, β-catenin, and RUNX2, were measured twice, and their association with disease activity and the Spondyloarthritis Research Consortium of Canada (SPARCC) score for SIJ were analyzed by univariate analysis of covariance. Results: A total of 116 patients completed the follow-up. The levels of sclerostin, OPG, noggin, DKK-1, and RUNX2 were increased, whereas those of VEGF and β-catenin were decreased. The levels of sclerostin and OPG were negatively correlated with disease duration. The levels of VEGF and β-catenin were significantly decreased (F = 7.866, P = 0.003; F = 4.106, P = 0.047) in patients with disease remission. A decrease in ESR was significantly correlated with decreased levels of Runx2 and SPARCC scores, with the levels of sclerostin being significantly elevated in the SPARCC-reduced group. There were no statistically significant differences between the imrecoxib and celecoxib groups (P> 0.05). Conclusion: Imrecoxib and celecoxib affect SIJ inflammation, disease activity, and the course of disease by regulating bone metabolism and angiogenesis in axSpA. Key Points •After treatment with imrecoxib and celecoxib, the levels of sclerostin, OPG, noggin, DKK-1, and RUNX2 were increased, whereas those of VEGF and β-catenin were decreased, correlating with the course of disease, disease activity, and SIJ inflammation. • A decrease in ESR was significantly correlated with a decrease in the levels of RUNX2 and SIJ inflammation.. • The levels of sclerostin were more significantly elevated in SIJ inflammation remission group.. •Imrecoxib and celecoxib affect SIJ inflammation by regulating bone metabolism and angiogenesis in axSpA.. [ABSTRACT FROM AUTHOR]

Propylene glycol methyl ether was directly synthesized from propylene and hydrogen peroxide under mild conditions via aluminum modified titanium silicalite-1 as a bifunctional catalyst. It has both active sites capable of epoxidation and active sites capable of ring opening reactions, thus realizing the one-pot preparation of propylene glycol methyl ether by propylene. The synergistic effect of Ti–Al on the catalytic performance and the distribution of propylene glycol methyl ether isomer were investigated in detail, and the synergistic catalysis between the two active sites was characterized. The gradual introduction of aluminum reduced the activation ability for hydrogen peroxide, but gradually increased the selectivity for propylene glycol methyl ether. Under the optimum conditions, the selectivity for propylene glycol methyl ether reached 91.53%. Combined with Density Functional Theory (DFT) calculations, the synergistic catalytic effect of doped Al and framework Ti in titanium silicalite-1 is discussed in detail from a microscopic perspective. Al increases the Lewis acid strength of Ti active sites and promotes the conversion of propylene to propylene oxide (PO), and simultaneously Ti increases the Brønsted acid strength of Al active sites and promotes the conversion of propylene oxide to propylene glycol ether. [ABSTRACT FROM AUTHOR]

Mg–15Gd–1Zn (wt.%) alloy was successfully prepared via the spark plasma sintering rapid solidification ribbons process. Microstructure investigation showed that the sintered alloys consisted of fine grains, the β1 phase, and long-perioded stacking ordered phase (LPSO). The sintering temperature and time have a significant effect on the microstructural evolution. A lower sintering temperature (430 °C) was beneficial for obtaining finer grain sizes with less than 5 μm and a higher content of β1 phase with a content of 3–15 vol.% and a size-distribution of (10–600) nm. A higher temperature for a longer sintering time, 450–470 °C and 5–10 min, helpfully promoted precipitating the abundantly lamellar LPSO phase, and its content was 2–10 vol.% for LPSO phase with the width of (10–100) nm. The mechanical properties indicated that the fine grain size and supersaturated solid solution contributed at least 50% of the yield stress, and the residual contribution was related to the β1 phase and LPSO phase strengthening, which were based on their contents and the sizes. [ABSTRACT FROM AUTHOR]

• The bipodal Ti species is used to model active center of TS-1 catalyst. • The preferable path of propylene epoxidation depends on the Ti-OOH active intermediate. • The bipodal Ti site exhibits Brønsted and Lewis acidity. • A poor selectivity toward PO is attributed to the stronger adsorption ability of PO and the excellent ring-opening ability of Ti-OH nucleophile. • The methoxy (CH3O) group is beneficial for the enhancement of the selectivity of PO. In order to probe into the effect of bipodal Ti species on the catalytic performance, the propylene epoxidation with H 2 O 2 over TS-1 catalyst with bipodal Ti site has been studied using an embedded quantum mechanical/molecular mechanics (QM/MM) approach, and the results shown that the bipodal Ti site has strong Brønsted and Lewis acidity, which not only greatly facilitates the epoxidation reaction but also lower selectivity toward the epoxy products. The excellent epoxidation activity is attributed to the Lewis acidity, in which, H 2 O 2 easily activated to generate active intermediates (i.e. , Ti-η1-OOH and Ti-η2-OOH) that is facile to transfer O atom to oxidize the propylene. The poor selectivity toward PO is also due to the Lewis acidity, which leads to the stronger adsorption ability of PO and excellent ring-opening ability of Ti-OH nucleophile to PO. The introduction of methoxy (CH3O) group is beneficial for the enhancement of the selectivity of PO, although it enhances the activation free energy for epoxidation to generate PO. The identifications about the relationship of the intrinsic selectivity and activity with bipodal Ti site would provide a clue for designing highly-efficient TS-1 catalysts in propylene epoxidation to PO from the theoretical point of view. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Study on matching hydrolysis rate of silicon source and titanium source in synthesis of TS-1. • Researches and challenges of reationally constructed Ti sites of TS-1 for oxidation reactions. • Study on the inhibition and treatment of non-framework titanium. • Effect of adjustment of crystallization process on the formation of titanium silicalite-1. Titanosilicate-1 (TS-1) has attracted extensive attention of researchers due to its unique shape-selective catalytic oxidation performance and excellent hydrothermal stability. However, the diffusion restriction and acid site restriction inside the molecular sieve will hinder the further industrial application of TS-1. Therefore, some modifications are needed to eliminate the influence of these two limitations. At present, although the methods of weakening or even eliminating diffusion restrictions are very mature, there is still some room for exploration due to the complex internal environment of TS-1 and the specific reaction mechanism. This paper comprehensively discussed the influence of the optimization of synthesis conditions on improving the content of framework Ti species and inhibiting the formation of non-framework Ti species. The methods for regulating the distribution, the electronic environment and the coordination states of Ti species were summarized, and the specific methods for eliminating non-framework Ti species after treatment were compared and analyzed. [ABSTRACT FROM AUTHOR]

Multiple sclerosis (MS) is a common autoimmune illness that is difficult to treat. The upregulation of Th17 cells is critical in the pathological process of MS. Hederagenol (Hed) has been shown to lower IL‐17 levels, although its role in MS pathophysiology is uncertain. In this study, we explore whether Hed could ameliorate MS by modulating Th17 cell differentiation, with the goal of identifying new treatment targets for MS. The experimental autoimmune encephalomyelitis (EAE) mouse model was conducted and Hed was intraperitoneally injected into mice. The weight was recorded and the clinical symptom grade was assessed. Hematoxylin‐eosin staining was carried out to determine the extent of inflammation in the spinal cord and liver. The luxol Fast Blue staining was performed to detect the pathological changes in the myelin sheath. Nerve damage was detected using NeuN immunofluorescence staining and terminal deoxynucleotidyl transferase dUTP nick‐end labeling staining. Immunohistology approaches were used to study alterations in immune cells in the spinal cord. The proportions of T cell subsets in the spleens were analyzed by flow cytometry. RORγt levels were measured using quantitative real‐time PCR or Western blot. The activity of the RORγt promoter was analyzed by Chromatin immunoprecipitation. Hed administration reduced the clinical symptom grade of EAE mice, as well as the inflammatory infiltration, demyelination, and cell disorder of the spinal cord, while having no discernible effect on the mouse weight. In addition, Hed treatment significantly reduced the number of T cells, particularly Th17 cells in the spinal cord and spleen‐isolated CD4+ T cells. Hed lowered the RORγt levels in spleens and CD4+ T cells and overexpression of RORγt reversed the inhibitory effect of Hed on Th17 differentiation. Hed decreased nerve injury by modulating Th17 differentiation through the RORγt promoter. Hed regulates Th17 differentiation by reducing RORγt promoter activity, which reduces nerve injury and alleviates EAE. [ABSTRACT FROM AUTHOR]

Medical image information may be polluted by noise in the process of generation and transmission, which will seriously hinder the follow-up image processing and medical diagnosis. In medical images, there is a typical mixed noise composed of additive white Gaussian noise (AWGN) and impulse noise. In the conventional denoising methods, impulse noise is first removed, followed by the elimination of white Gaussian noise (WGN). However, it is difficult to separate the two kinds of noises completely in practical application. The existing denoising algorithm of weight coding based on sparse nonlocal regularization, which can simultaneously remove AWGN and impulse noise, is plagued by the problems of incomplete noise removal and serious loss of details. The denoising algorithm based on sparse representation and low rank constraint can preserve image details better. Thus, a medical image denoising algorithm based on sparse nonlocal regularization weighted coding and low rank constraint is proposed. The denoising effect of the proposed method and the original algorithm on computed tomography (CT) image and magnetic resonance (MR) image are compared. It is revealed that, under different σ and ρ values, the PSNR and FSIM values of CT and MRI images are evidently superior to those of traditional algorithms, suggesting that the algorithm proposed in this work has better denoising effects on medical images than traditional denoising algorithms. [ABSTRACT FROM AUTHOR]

Fas is a positive regulator of Th17 cells differentiation in experimental autoimmune encephalomyelitis (EAE). However, its upstream regulators are still not fully determined. This study was designed to explore the upstream regulators of Fas in regulating Th17 cells differentiation in EAE. The mouse model of EAE was established by myelin oligodendrocyte glycoprotein injection. Th17 cells differentiation was induced by IL-23, IL-6 and TGF-β. Down-regulated Hsp70 and miR-374c and up-regulated Fas were observed in the spleen and brain of EAE mice. Hsp70 overexpression evidently reduced Fas protein level, but not mRNA level. The luciferase reporter assay indicated that miR-374c targets Fas. Overexpression of miR-374c down-regulated the mRNA and protein level of Fas. The concentration of IL-17A in CD4+ T-cells was reduced by miR-374c or Hsp70 overexpression, and Fas overexpression altered this trend. Hsp70 did not regulate the expression of miR-374c, and likewise, miR-374c did not regulate the expression of Hsp70. Further results suggested that Hsp70 and miR-374c regulated Fas expression through different ways to affect Th17 cells differentiation in EAE. This study suggested that down-regulated miR-374c and Hsp70 promote Th17 cell differentiation by inducing Fas expression in EAE. [ABSTRACT FROM AUTHOR]