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A wheelset bearing is a crucial energy transmission element in high-speed trains. Any parts of the wheelset bearing that have faults may endanger the safety of the railway service. Therefore, it is important to monitor the running condition of a wheelset bearing. The multifault on a wheelset bearing is very common, and these impulsive components generated by different types of faults may interact with each other, which increases the difficulty of entirely identifying those faults. To solve the multifault problem, this paper proposed a hierarchical shift-invariant K-means singular value decomposition (H-SI-K-SVD) to hierarchically separate those multifault impulsive components based on their fault power levels. Each of the separated impulse signals contains only one fault impulse, and the fault information could be highlighted both in time domain and frequency domain. In addition, the sparsity of envelope spectrum (SES) is introduced as an indicator to adaptively tune a key parameter in this method. The effectiveness of the proposed method is verified by both simulation and experimental signals. Compared with ensemble empirical model decomposition (EEMD), the proposed method exhibits better performance in separating the multifault impulsive components and detecting the faults of a wheelset bearing. [ABSTRACT FROM AUTHOR]

Spinal cord injury (SCI) is a highly disabling disorder for which few effective treatments are available. Grape seed proanthocyanidins (GSPs) are polyphenolic compounds with various biological activities. In our preliminary experiment, GSP promoted functional recovery in rats with SCI, but the mechanism remains unclear. Therefore, we explored the protective effects of GSP on SCI and its possible underlying mechanisms. We found that GSP promoted locomotor recovery, reduced neuronal apoptosis, increased neuronal preservation, and regulated microglial polarisation in vivo. We also performed in vitro studies to verify the effects of GSP on neuronal protection and microglial polarisation and their potential mechanisms. We found that GSP regulated microglial polarisation and inhibited apoptosis in PC12 cells induced by M1-BV2 cells through the Toll-like receptor 4- (TLR4-) mediated nuclear factor kappa B (NF-κB) and phosphatidylinositol 3-kinase/serine threonine kinase (PI3K/AKT) signaling pathways. This suggests that GSP regulates microglial polarisation and prevents neuronal apoptosis, possibly by the TLR4-mediated NF-κB and PI3K/AKT signaling pathways. [ABSTRACT FROM AUTHOR]

Inspecting the smoothness and durability of the exterior and interior surfaces of manufactured products such as large passenger aircraft requires utilizing manufacturing precision instruments. Manual techniques are mainly adopted in inspections, which are, however, much costly and have low efficiency. Moreover, manual operation is more prone to missing and false inspections. To cope with these issues, effective precision instruments have been needed to devise intelligent inspections for impalpable damages as necessary tools. When many inspection tasks are investigated, very few public datasets are available to recognize the intelligent inspection of precision instruments. On the other hand, precision instruments can be applied to a wide variety of damages. YOLO V3 was proposed based on acquiring and processing the image appearances, which deal with the surface inspection of the precision instrument in this study. The image dataset of the impalpable damage was initially established. More specifically, the YOLO V3 detection network is leveraged to roughly calculate the location of the damage appearances and identify the damage type. Afterward, the designed level set algorithm was employed to obtain more accurate damage locations in the image block utilizing the characteristics of different types of damages. Finally, a quantitative analysis was performed employing the refined detection results. A deep architecture that can intelligently conduct damage detection was proposed. Besides, the proposed method exhibited a strong tolerance for unknown types of damages and excellent flexibility and adaptability. Extensive experimental results demonstrated that the proposed method can alleviate the shortcomings of the traditional inspection methods. Thus, it provided technical guidance for the applications of the intelligent orbital inspection of the robots. The proposed method with a more precise and noninvasive inspection technique remarkably accelerates the inspection time of impalpable damages on surfaces. [ABSTRACT FROM AUTHOR]

Intervertebral disc degeneration (IDD) is one of the main causes of low back pain (LBP), which severely reduces the quality of life and imposes a heavy financial burden on the families of affected individuals. Current research suggests that IDD is a complex cell-mediated process. Inflammation, oxidative stress, mitochondrial dysfunction, abnormal mechanical load, telomere shortening, DNA damage, and nutrient deprivation contribute to intervertebral disc cell senescence and changes in matrix metabolism, ultimately causing IDD. Natural products are widespread, structurally diverse, afford unique advantages, and exhibit great potential in terms of IDD treatment. In recent years, increasing numbers of natural ingredients have been shown to inhibit the degeneration of nucleus pulposus cells through various modes of action. Here, we review the pharmacological effects of natural products on nucleus pulposus cells and the mechanisms involved. An improved understanding of how natural products target signalling pathways will aid the development of anti-IDD drugs. This review focuses on potential IDD drugs. [ABSTRACT FROM AUTHOR]

Schisandrae Fructus (SF), the fruit of Schisandra chinensis (Turcz.) Baillon, has been used for the treatment of liver injury and metabolism-related disorders in China. The objective of this study was to investigate the effects of supplementation with ethanol extract of SF seed (EtSF-S) on serum/hepatic lipid and glucose levels as well as fecal total cholesterol (TC) contents in mice fed a normal diet (ND) or high-fat/fructose diet (HFFD) containing 15% lard oil and 15% fructose. Female ICR mice (18–20 g in body weight) were fed with ND or HFFD for 3 months, and then EtSF-S was added to both chow diets at increasing concentrations of 1, 5, and 10% (w/w). Thirty days later, serum and hepatic lipids, including TC, triglyceride (TG), high-density lipoprotein (HDL), low-density lipoprotein (LDL), and glucose, were measured. Dietary supplementation with EtSF-S reduced hepatic TC (36 and 18%) and TG levels (38 and 28%) and increased serum HDL/LDL ratio (16 and 26%) in both ND- and HFFD-fed mice, respectively. Moreover, supplementation with EtSF-S elevated serum HDL (31%) in HFFD-fed mice and reduced serum LDL (27%) in ND-fed mice. EtSF-S treatment reduced fat mass (40%) in ND-fed mice and increased fecal TC contents (33%) in HFFD-fed mice. EtSF-S supplementation decreased hepatic glucose contents (29%) in both ND- and HFFD-fed mice. However, diet supplemented with EtSF-S elevated serum TG levels (up to 123%) and hepatic size (28%), but more importantly, suppressed the body weight gain (approximately 130%) in mice fed with HFFD. These findings suggested that dietary supplementation with EtSF-S as natural herbal function food may be a useful strategy for the treatment of patients with fatty liver disease or overweight without a high intake of sugar and fat. [ABSTRACT FROM AUTHOR]

Introduction. Nonspecific chronic low back pain (NCLBP) became a public health and economic problem. Acupoint injection was used widely for patients with NCLBP. However, there were inconsistent results on the efficacy for these people. Therefore, this review was performed to systematically assess the efficacy and safety of acupoint injection. Materials and Methods. The literature sources were collected via EMBASE, Medline, CENTRAL, CINAHL, CNKI, VIP, Wanfang, and Sino-Med Database from their inception to October 13, 2019. Endnote X7, widely used document management software, was used to manage and screen the literature sources. Each record was screened according to the predetermined inclusion criteria by two review authors independently. Quality assessment tool, "Risk of table," was used to assess the quality of the included studies according to the recommendation of the Cochrane Handbook for Systematic Reviews of Interventions. Data extraction was performed by one reviewer and verified by another reviewer. Any disagreement was addressed via consulting with a third reviewer in the abovementioned processes. All procedures were performed according to the Cochrane Handbook for Systematic Reviews of Interventions. Results. This review included 13 studies involving 1381 patients with NCLBP. Quantitative analysis results indicated that there is no sufficient evidence that acupoint injection can improve the pain of patients with low back pain based on two trails: Visual Analogue Scale (VAS: MD = −1.33, 95% confidence interval (95% CI) −3.30 to 0.64, P = 0.18 , random-effect model). When assessing the effectiveness of acupoint injection therapy, the results indicated that acupoint injection can improve the effective rate for nonspecific chronic low back pain (OR = 3.64, 95% CI 2.4 to 5.21, P < 0.0001 , fixed-effect model). Conclusion. There is insufficient evidence to indicate that acupoint injection therapy could improve the pain for patients with NCLBP. However, the level of evidence was downgraded to "very low quality" because of the poor methodological quality and clinical heterogeneity. The results should be interpreted with caution. Higher quality RCTs with more appropriate comparison, more objective outcome instruments, and adequate follow-up periods are necessary to assess the efficacy of acupoint injection for NCLBP. The PROSPERO Research registration identifying number is CRD42019119158. [ABSTRACT FROM AUTHOR]

Stroke induces a robust inflammatory response. However, it still lacks a systematic view of the various immune cell types due to the limited numbers of fluorophore used in the traditional FACS technique. In our current study, we utilized the novel technique mass cytometry (CyTOF) to analyze multiple immune cell types. We detected these immune cells from the ischemic brain, peripheral blood, spleen, and bone marrow at different time courses after stroke. Our data showed (1) dynamic changes in the immune cell numbers in the ischemic brain and peripheral organs. (2) The expression levels of cell surface markers indicate the inflammation response status after stroke. Interestingly, CD62L, a key adhesion molecule, regulates the migration of leukocytes from blood vessels into secondary lymphoid tissues and peripheral tissues. (3) A strong leukocyte network across the brain and peripheral immune organs was identified using the R program at day 1 after ischemia, suggesting that the peripheral immune cells dramatically migrated into the ischemic areas after stroke. This study provides a systematic, wide view of the immune components in the brain and peripheral organs for a deep understanding of the immune response after ischemic stroke. [ABSTRACT FROM AUTHOR]