Gear fault diagnosis under variable conditions with intrinsic time-scale decomposition-singular value decomposition and support vector machine

Zhanqiang Xing,Jianfeng Qu,Yi Chai,Qiu Tang,Yuming Zhou 대한기계학회 2017 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.31 No.2

The gear vibration signal is nonlinear and non-stationary, gear fault diagnosis under variable conditions has always been unsatisfactory. To solve this problem, an intelligent fault diagnosis method based on Intrinsic time-scale decomposition (ITD)-Singular value decomposition (SVD) and Support vector machine (SVM) is proposed in this paper. The ITD method is adopted to decompose the vibration signal of gearbox into several Proper rotation components (PRCs). Subsequently, the singular value decomposition is proposed to obtain the singular value vectors of the proper rotation components and improve the robustness of feature extraction under variable conditions. Finally, the Support vector machine is applied to classify the fault type of gear. According to the experimental results, the performance of ITD-SVD exceeds those of the time-frequency analysis methods with EMD and WPT combined with SVD for feature extraction, and the classifier of SVM outperforms those for K-nearest neighbors (K-NN) and Back propagation (BP). Moreover, the proposed approach can accurately diagnose and identify different fault types of gear under variable conditions.

Antifungal bio-coating of endotracheal tube built by overexpressing MCP1 gene of Saccharomyces boulardii and employing hydrogel as a “house” antagonize Candida albicans

Yunyun Wei,Jianfeng Qiu,Ziqiang Han,Xuanyi Wang,Hui Zhang,Xinya Hou,Xiangwei Lv,Xiaolong Mao 한국생체재료학회 2023 생체재료학회지 Vol.27 No.00

Background For some ICU patients, an artificial airway must be established with an endotracheal tube, but Candida albicans can easily adhere to the tube surface and form a biofilm, leading to potentially life threatening fungal infections. Therefore, it is urgent to prevent and reduce C. albicans infections introduced by the endotracheal tube. However, there are few antifungal drugs effective against C. albicans, and each of these drugs may have adverse effects on human cells. Saccharomyces boulardii is regarded as an alternative strategy to inhibit the adhesion of C. albicans, but it is affected by environmental stress. We hypothesized that it is feasible to strengthen the antagonistic ability of S. boulardii via encapsulating and genetically modification. Methods In this study, a bioactive material carrying the overexpressed MCP1 gene of Saccharomyces boulardii was constructed based on one-step photo-crosslinking. This material achieved spatial growth control of S. boulardii by encapsulating each S. boulardii cell within a hydrogel pore. The bioactive material was coated on an endotracheal tube and tested for its ability to inhibit the adhesion of C. albicans. Additionally, the material’s antagonistic activity towards C. albicans was evaluated by detecting intracellular Adenosine-triphosphate content, reactive oxygen species level and the activity of antioxidative enzymes. Tissue invasion experiment was executed to further evaluate the antiadhesion ability of S. boulardii bio-coating. Results Encapsulating the overexpression of MCP1 by S. boulardii in hydrogel pores enhanced the viability of probiotics in the presence of high salt and oxidation stress. When used as the coating of an endotracheal tube, the S. boulardii bioactive material efficiently inhibited the adhesion of C. albicans by impairing the activities of superoxide dismutase and catalase and disturbing mitochondrial functions. In vivo, the S. boulardii bioactive material coating displayed good biocompatibility and reduced the host tissue invasion and virulence of C. albicans. Conclusions The integration of genetic modification and immobilization model breaks the bottleneck of previous application of microorganisms, and provides a new way to prevent fungal infections introduced by endotracheal tubes.

Bombyx mori used as a fast detection model of liver melanization after a clinical drug – Acetaminophen exposure

Yue He,Xu Xu,Jianfeng Qiu,Weimin Yin,Yang-Hu Sima,Shi-Qing Xu 한국응용곤충학회 2020 Journal of Asia-Pacific Entomology Vol.23 No.1

Acetaminophen (APAP) is an effective and widely used analgesic. However, APAP overdose is the principal cause of acute liver failure (ALF) in many countries. Here, we report the phenomenon of liver melanization which occurred before APAP-induced ALF in mice. A melanic surface induced by APAP which was time- and dosedependent in the silkworm invertebrate model was observed. In addition, an APAP-induced acute tissue failure model (ATF) was established using a metabolic detoxification tissue fat body which simulated mouse liver. An investigation of the anabolic mechanism of melanin in experimental animals showed that dopaquinone and dopamine which were synthesized from tyrosine via dopa in silkworms were further metabolized to melanin, while in mice, epinephrine was synthesized via the dopamine branch and melanin was only synthesized via the dopaquinone branch. On this basis, it is proposed that melanin-metabolic levels in plasma could be used as an early diagnostic marker of APAP overdose and the black spots on insect epidermis could be used as a fast detection model of toxicity.

Comparison of Hybridization Behavior between Double and Single Strand of Targets and the Application of Asymmetric PCR Targets in cDNA Microarray

Wei, Qing,Liu, Sanzhen,Huang, Jianfeng,Mao, Xueying,Chu, Xiaohui,Wang, Yu,Qiu, Minyan,Mao, Yumin,Xie, Yi,Li, Yao Korean Society for Biochemistry and Molecular Biol 2004 Journal of biochemistry and molecular biology Vol.37 No.4

Double stranded targets on the cDNA microarray contain representatives of both the coding and noncoding strands, which will introduce hybridization competition with probes. Here, the effect of double and single strands of targets on the signal intensity and the ratios of Cy5/Cy3 within the same slide were compared. The results show that single stranded targets can increase the hybridization efficiency without changing the Cy5/Cy3 ratio. Based on these results, a new strategy was established by generating cDNA targets with asymmetric PCR, instead of conventional PCR, to increase the sensitivity of the cDNA microarray. Furthermore, the feasibility of this approach was validated. The results indicate that the cDNA microarray system based on asymmetric PCR is more sensitive, with no decrease in the reliability and reproducibility as compared with that based on conventional symmetric PCR.

Responsive manganese-based nanoplatform amplifying cGAS-STING activation for immunotherapy

Qingbin He,Runxiao Zheng,Junchi Ma,Luyang Zhao,Yafang Shi,Jianfeng Qiu 한국생체재료학회 2023 생체재료학회지 Vol.27 No.00

Background The activation of the cyclic guanosine monophosphate-adenosine monophosphate synthasestimulator of interferon genes (cGAS-STING) signaling pathway has attracted great attention for its ability to up-regulate innate immune response and thus enhance cancer immunotherapy. However, many STING agonists limit the further advancement of immunotherapy due to weak tumor responsiveness or low activation efficiency. The responsive and effective activation of cGAS-STING signaling in tumors is a highly challenging process. Methods In this study, a manganese-based nanoplatform (MPCZ NPs) was constructed that could responsively and efficiently generate more manganese ions (Mn2+) and reactive oxygen species (ROS) to activate cGAS-STING signaling pathway. Briefly, manganese dioxide (MnO2) was loaded with zinc protoporphyrin IX (ZPP) molecule and coated by polydopamine (PDA) embedded with NH4HCO3 to obtain MPCZ NPs. Additionally, MPCZ NPs were evaluated in vitro and in vivo for their antitumor effects by methyl thiazolyl tetrazolium (MTT) assay and TUNEL assays, respectively. Results In this system, tumor responsiveness was achieved by exogenous (laser irradiation) and endogenous (high levels GSH) stimulation, which triggered the collapse or degradation of PDA and MnO2. Moreover, the release of Mn2+ augmented the cGAS-STING signaling pathway and enhanced the conversion of hydrogen peroxide (H2O2) to hydroxyl radical (·OH) under NIR laser irradiation. Furthermore, the release of ZPP and the elimination of GSH by MPCZ NPs inhibited HO-1 activity and prevented ROS consumption, respectively. Conclusions This adopted open source and reduce expenditure strategy to effectively generate more ROS and Mn2+ to responsively activate cGAS-STING signaling pathway, providing a new strategy for improving immunotherapy.