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The non-uniformity of temperature field distribution of long-span steel structure is proportional to the intensity of solar radiation. Based on the background of Guangzhou Baiyun Station large-span complex steel roof structure, this paper studies the non-uniformtemperature field distribution of large-span steel structure under the Summer Solstice daily radiation-thermal-fluid coupling action based on Star-ccm, finite element software, and uses Spa2000 software to analyze the stress and deformation of steel roof under temperature action. Combined with the on-site temperature monitoring, the maximum difference with the measured value is 2.5°C compared with the numerical simulation results, which verifies the validity of the finite element simulation. The results show that: from 8:00, with the increase of solar altitude angle, the intensity of solar radiation increases, the temperature rises, and the temperature distribution of large-span steel structure becomes more and more non-uniform. From14:00 to18:00, the solar radiation weakens, and the temperature distribution tends to be uniform. Finally, reasonable construction suggestions and measures are proposed to reduce the adverse effects of temperature effects, which can provide theoretical references for the safe construction and normal operation of large-span steel structures located in the subtropics. [ABSTRACT FROM AUTHOR]

The depressed scar and the hypertrophic scar are very common in the abdomen after operation. How to reduce the scar after operation becomes more and more important. The three-dimensional Z-plasty is performed on the abdominal skin & subcutaneous tissue and its effectivity is perfect. It seems that this is a logical treatment of depressed scar or hypertrophic scar in the abdomen. [ABSTRACT FROM AUTHOR]

Traditional fault diagnosis methods require complex signal processing and expert experience, and the accuracy of fault identification is low. To solve these problems, a fault diagnosis method based on an improved convolutional neural network (CNN) is proposed. Based on the traditional CNN model, a variety of convolution stride modes were added to extract features of different scales of signals and expand the feature dimension. Firstly, the vibration signals were collected and grouped. Then, the data were divided into a training set and a test set and input into improved CNN for feature extraction and model training to realize fault identification. The proposed model achieved a classification accuracy of 99.3% when testing the vibration data of the armored vehicle. Finally, the proposed model was used to classify different fault types of planetary gearboxes. The gradient-weighted class activation mapping (Grad-CAM) method was used to visualize the classification weight of samples. The results showed that the classification accuracy reaches 98% under various working conditions of the planetary gearbox. [ABSTRACT FROM AUTHOR]

Traditional prognostics and health management (PHM) methods for fault detection require complex signal processing and manual fault feature extraction, and the accuracy is low. To address these problems, a fault diagnosis method of planetary gearbox based on deep belief networks (DBNs) is proposed. Firstly, the vibration signals of the planetary gearbox are collected and analyzed in the time domain and the frequency domain. Then, the DBN model and optimal parameters are determined to meet the task requirements. Finally, the vibration data is divided into training set and test set and input into the DBN model, which can realize the automatic feature extraction and fault recognition of vibration signals. The results show that the identification accuracy reaches 97% under five working conditions of planetary gearbox. [ABSTRACT FROM AUTHOR]

Background/Aims: Emerging evidence points towards an important role of long noncoding RNAs (lncRNAs) in the tumorigenesis and progression of gastric cancer (GC). MT1JP has recently been reported to be differentially expressed and act as a tumor suppressor in different tumors, with its mechanisms not fully understood in GC. Methods: RT-qPCR was used to detect the expression of MT1JP, miR-214-3p and RUNX3 in tumor tissues and cell lines of GC. The CCK-8 assay, colony formation, Transwell assay and wound healing assay were used to evaluate the proliferation, invasion and migration of GC cells, respectively. Bioinformatics analysis and luciferase reporter assay were performed to disclose the interaction between MT1JP, miR-214-3p and RUNX3. Western blot and immunofluorescence were applied to assess the downstream signaling of RUNX3. Results: MT1JP was found downregulated in GC tissues and cells. Low expression of MT1JP was significantly correlated with advanced TNM stage and lymphatic metastasis. The expression of plasma MT1JP was also found decreased in GC patients compared to healthy controls, with an area under the ROC curve (AUC) of 0.649 for diagnosis of GC. Gain- and loss-of-function of MT1JP revealed that MT1JP functioned as a ceRNA for miR-214-3p to facilitate RUNX3 expression and then upregulated p21 and Bim levels suppressing GC cell proliferation, invasion and migration, and promoting apoptosis. Furthermore, MT1JP overexpression suppressed tumor growth and inhibited the expression of miR-214-3p and proliferation antigen Ki-67, but increased the expression of RUNX3, p21 and Bim in vivo. Conclusions: Our results suggest a potential ceRNA regulatory network involving MT1JP regulates RUNX3 expression by competitively binding endogenous miR-214-3p in tumorigenesis and progression of GC. This mechanism may contribute to a better understanding of GC pathogenesis and provide potential therapeutic strategy for GC. [ABSTRACT FROM AUTHOR]

Objectives: Long noncoding RNAs (lncRNAs) play important roles in cancer development and progression. The deregulated expression of LINC00978 has been reported in human cancers. However, the expression pattern and biological roles of LINC00978 in gastric cancer (GC) remain unclear. In this study, we investigated the potential roles and clinical value of LINC00978 in gastric cancer. Materials and methods: QRT-PCR was performed to investigate the expression of LINC00978 in gastric cancer cell lines, tissues and serum samples. Cell counting, colony formation, transwell migration and matrigel invasion assays were performed to determine the effects of shRNA-mediated knockdown of LINC00978 on gastric cancer cell functions. In vivo tumour growth assay was also conducted. Flow cytometry, immunohistochemistry, western blot and qRT-PCR were used for potential mechanism study. Results: LINC00978 expression level was elevated in GC tumour tissues, serum samples and cell lines. The expression level of LINC00978 was significantly correlated with tumour size (P = 0.02), lymphatic metastasis (P = 0.009) and TNM stage (P = 0.009). LINC00978 knockdown inhibited the proliferation of GC cells by suppressing cell cycle progression and inducing apoptosis. LINC00978 knockdown also inhibited the migration and invasion of GC cells. In addition, LINC00978 knockdown inhibited the activation of TGF-β/ SMAD signalling pathway and the process of epithelial-mesenchymal transition (EMT) in GC cells. Moreover, the in vivo tumorigenicity of LINC00978 knockdown GC cells in mice was significantly decreased. Conclusions: LINC00978 promotes gastric cancer progression and may serve as a potential biomarker for GC. [ABSTRACT FROM AUTHOR]

The kurtosis-based indexes are usually used to identify the optimal resonant frequency band. However, kurtosis can only describe the strength of transient impulses, which cannot differentiate impulse noises and repetitive transient impulses cyclically generated in bearing vibration signals. As a result, it may lead to inaccurate results in identifying resonant frequency bands, in demodulating fault features and hence in fault diagnosis. In view of those drawbacks, this manuscript redefines the correlated kurtosis based on kurtosis and auto-correlative function, puts forward an improved correlated kurtosis based on squared envelope spectrum of bearing vibration signals. Meanwhile, this manuscript proposes an optimal resonant band demodulation method, which can adaptively determine the optimal resonant frequency band and accurately demodulate transient fault features of rolling bearings, by combining the complex Morlet wavelet filter and the Particle Swarm Optimization algorithm. Analysis of both simulation data and experimental data reveal that the improved correlated kurtosis can effectively remedy the drawbacks of kurtosis-based indexes and the proposed optimal resonant band demodulation is more accurate in identifying the optimal central frequencies and bandwidth of resonant bands. Improved fault diagnosis results in experiment verified the validity and advantage of the proposed method over the traditional kurtosis-based indexes. [ABSTRACT FROM AUTHOR]

Mesenchymal stem cells (MSCs) are a component of the tumor microenvironment and can promote the development of gastric cancer through paracrine mechanism. However, the effects of MSC-exosomes (MSC-ex) on gastric cancer are less clear. The present study reported that MSC-ex promoted the proliferative and metastatic potential of gastric cancer cells ex vivo. It was found that MSC-ex enhanced the migration and invasion of HGC-27 cells via the induction of the epithelial-mesenchymal transition. MSC-ex increased the expression of mesenchymal markers and reduced the expression of epithelial markers in gastric cancer cells. MSC-ex also enhanced the tumorigenicity of gastric cancer cells ex vivo. MSC-ex induced the stemness of gastric cancer cells. The expression of octamer-binding transcription factor 4, ex determining region Y-box 2 and Lin28B significantly increased in gastric cancer cells treated with MSC-ex. The present study further demonstrated that MSC-ex elicited these biological effects predominantly via the activation of the protein kinase B signaling pathway. Taken together, the present findings provided novel evidence for the role of MSC-ex in gastric cancer and a new opportunity for improving the efficiency of gastric cancer treatment by targeting MSC-ex. [ABSTRACT FROM AUTHOR]