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      • KCI등재

        Addition of Theophylline or Increasing the Dose of Inhaled Corticosteroid in Symptomatic Asthma: A Meta-Analysis of Randomized Controlled Trials

        Yan Wang,Kexiong Lin,Changzheng Wang,Xiuqing Liao 연세대학교의과대학 2011 Yonsei medical journal Vol.52 No.2

        Purpose: Low-dose theophylline has anti-inflammatory effects. The aim of this study was to evaluate the effects of adding theophylline compared with increasing the dose of inhaled corticosteroid (ICS) on symptomatic asthma. Materials and Methods: The associated literature was acquired through deliberate searching and selected based on the established inclusion criteria for publications. The extracted data were further analyzed by a meta-analysis. Results: Four randomized, controlled,parallel studies were selected. Addition of theophylline produced a greater increase of forced expiratory volume in one second as %predicted (FEV1pred) by 2.49% [95% confidence interval (CI) 1.99-3.00; z = 9.70; p < 0.001], compared with increasing the dose of ICS. There was no difference between the two treatments in terms of peak expiratory flow (PEF). Conclusion: Addition of theophylline to ICS has similar therapeutic effects on improving lung function as increasing the dose of ICS in the treatment of symptomatic asthma.

      • KCI등재

        Direct Electrodeposition to Fabricate 3D Graphene Network Modified Glassy Carbon Electrode for Sensitive Determination of Tadalafil

        Changzheng Xin,ShanShan Gao,Yaxin Din,Yanju Wu,Fei Wang 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2019 NANO Vol.14 No.1

        In this work, pulse potential method (PPM) was presented to fabricate directly three-dimensional graphene (3DG) network on the surface of glassy carbon electrode (GCE). The morphological characteristic of 3DG network were investigated by means of Raman spectra, scanning electron microscopy (SEM) and electrochemical experiments. The 3DG network as a new voltammetric material was used to develop a high-sensitive electrochemical sensor for determination of tadalafil. Electrochemical tests showed that the 3DG network can help to enhance response due to the large accessible surface area as well as its excellent conductivity. Under the optimum conditions, the electrochemical response showed a linear relationship with tadalafil concentrations in the range of 5.0 x 10 -8 – 2.5 x 10 -5 mol L -1, and a low detection limit of 1.0 x 10 -8 mol L -1 was achieved for tadalafil. Moreover, the fabricated electrochemical sensor exhibited excellent selectivity, stability, reproducibility and repeatability, which make it very suitable for analytical applications for the trace level determination of tadalafil.

      • KCI등재

        Application of different surrogate models on the optimization of centrifugal pump

        Wenjie Wang,Ji Pei,Shouqi Yuan,Jinfeng Zhang,Jian-Ping Yuan,Changzheng Xu 대한기계학회 2016 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.30 No.2

        An optimization process for impellers was carried out based on numerical simulation, Latin hypercube sampling (LHS), surrogate model and Genetic algorithm (GA) to improve the efficiency of residual heat removal pump. The commercial software ANSYS CFX 14.5 was utilized to solve the Reynolds-averaged Navier-Stokes equations by using the Shear stress transport turbulence model. The impeller blade parameters, which contain the blade inlet incidence angle ∆β, blade wrap angle φ, and blade outlet angle β 2 , were designed by random sample points according to the LHS method. The efficiency predicted under the design flow rate was selected as the objective function. The best combination of parameters was obtained by calculating the surrogate model with the GA. Meanwhile, the prediction accuracies of three surrogate models, namely, Response surface model (RSM), Kriging model, and Radial basis neural network (RBNN), were compared. Results showed that the calculated findings agree with the experimental performance results of the original pump. The RSF model predicted the highest efficiency, while the RBNN had the highest prediction accuracy. Compared with the simulated efficiency of the original pump, the optimization increased efficiency by 8.34% under the design point. Finally, the internal flow fields were analyzed to understand the mechanism of efficiency improvement. The optimization process, including the comparison of the surrogate models, can provide reference for the optimization design of other pumps.

      • KCI등재

        Initial fault diagnosis of bearing based on AVMD-SE and multiscale enhanced morphological top-hat filter

        Tong Wang,Changzheng Chen,Yuanqing Luo,Siyu Zhao,Shaohui Huang 대한기계학회 2022 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.36 No.12

        Early fault signature detection and background noise removal are essential for bearing fault diagnosis. A novel multiscale enhanced morphological top-hat filter fault diagnosis method, adaptive variational mode decomposition-sample entropy-multiscale enhanced top-hat filter (AVMD-SE-MEMTF), is proposed based on AVMD-SE noise reduction. First, gray wolf optimization algorithm is proposed to optimize the VMD to achieve the optimal decomposition parameters adaptively and combine with SE to eliminate the high noise components and improve the noise reduction effect. Then, based on the pulse extraction property of morphological operations, the concept of MEMTF is proposed. To enhance the multiscale index selection strategy, a synthesis method of eigenfrequency envelope coefficients is constructed to increase the accuracy of the operator during the vibration signal process. Finally, experimental and engineering results show that the proposed method has good diagnostic performance for weak faults in the presence of noise interference.

      • KCI등재

        Omalizumab Improves Quality of Life and Asthma Control in Chinese Patients With Moderate to Severe Asthma: A Randomized Phase III Study

        Jing Li,Jian Kang,Changzheng Wang,Jing Yang,Linda Wang,Ioannis Kottakis,Michael Humphries,Nanshan Zhong,China Omalizumab Study Group 대한천식알레르기학회 2016 Allergy, Asthma & Immunology Research Vol.8 No.4

        Purpose: Omalizumab is the preferred add-on therapy for patients with moderate-to-severe persistent allergic asthma and has demonstrated efficacy and safety in various ethnicities. This study evaluated the efficacy and safety of omalizumab in Chinese patients with moderate-to-severe allergic asthma. Methods: This randomized, double-blind, parallel-group, placebo-controlled, phase III study assessed lung function, quality of life, asthma control, and safety of omalizumab after 24-week therapy in Chinese patients (18-75 years of age). Results: A total of 616 patients were randomized (1:1) to omalizumab or placebo. The primary endpoint, least squares mean treatment difference (LSM-TD) in morning peak expiratory flow (PEF) (omalizumab vs placebo), at Weeks >20-24 was 8.85 L/min (Full analysis set; P=0.062). Per-protocol analysis set showed significant improvements with LSM-TD of 11.53 L/min in mean mPEF at Weeks >20-24 (P=0.022). The FEV1 % predicted was significantly improved with omalizumab vs placebo from 8 to 24 weeks (after 24-week treatment: LSM-TD=4.12%; P=0.001). At Week 24, a higher proportion of omalizumab-treated patients achieved clinically relevant improvements in standardized AQLQ (58.2% vs 39.3%; LSM=0.51 vs 0.10; P<0.001) and ACQ (49.5% vs 35.5%; LSM=-0.51 vs -0.34; P=0.002) scores vs placebo. Total and nighttime symptom scores reduced significantly with omalizumab vs placebo (LSM-TD=-0.21, P=0.048 and -0.12, P=0.011, respectively). Although the study was not powered to study differences in exacerbation rates (P=0.097), exacerbations in winter months were less frequent in the omalizumab vs placebo group (2 vs 21). Adverse event and severe adverse event rates were comparable between omalizumab and placebo. Conclusions: Omalizumab improves lung function, quality of life, and asthma control in Chinese patients with moderate-to-severe persistent allergic asthma and has a good safety profile.

      • Ocean Economy and Fault Diagnosis of Electric Submersible Pump applied in Floating platform

        Panlong ZHANG,Tingkai CHEN,Guochao WANG,Changzheng PENG 국제이네비해양경제학회 2017 International Journal of e-Navigation and Maritime Vol.6 No.1

        Ocean economy plays a crucial role in the strengthening maritime safety industry and in the welfare of human beings. Electric Submersible Pumps (ESP) have been widely used in floating platforms on the sea to provide oil for machines. However, the ESP fault may lead to ocean environment pollution, on the other hand, a timely fault diagnosis of ESP can improve the ocean economy. In order to meet the strict regulations of the ocean economy and environmental protection, the fault diagnosis of ESP system has become more and more popular in many countries. The vibration mechanical models of typical faults have been able to successfully diagnose the faults of ESP. And different types of sensors are used to monitor the vibration signal for the signal analysis and fault diagnosis in the ESP system. Meanwhile, physical sensors would increase the fault diagnosis challenge. Nowadays, the method of neural network for the fault diagnosis of ESP has been applied widely, which can diagnose the fault of an electric pump accurately based on the large database. To reduce the number of sensors and to avoid the large database, in this paper, algorithms are designed based on feature extraction to diagnose the fault of the ESP system. Simulation results show that the algorithms can achieve the prospective objectives superbly.

      • KCI등재

        Hospitalization Due to Asthma Exacerbation: A China Asthma Research Network (CARN) Retrospective Study in 29 Provinces Across Mainland China

        Jiangtao Lin,Bin Xing,Huaping Tang,Lan Yang,Yadong Yuan,Yuhai Gu,Ping Chen,Xiaoju Liu,Jie Zhang,Huiguo Liu,Changzheng Wang,Wei Zhou,Dejun Sun,Yiqiang Chen,Zhuochang Chen,Mao Huang,Qichang Lin,Chengpin 대한천식알레르기학회 2020 Allergy, Asthma & Immunology Research Vol.12 No.3

        Purpose: Details of patients hospitalized for asthma exacerbation in mainland China are lacking. To improve disease control and reduce economic burden, a large sample survey among this patient population is indispensable. This study aimed to investigate the clinical characteristics and outcomes of such patients. Methods: A retrospective study was conducted on patients hospitalized for asthma exacerbation in 29 hospitals of 29 regions in mainland China during the period 2013 to 2014. Demographic features, pre-admission conditions, exacerbation details, and outcomes were summarized. Risk factors for exacerbation severity were analyzed. Results: There were 3,240 asthmatic patients included in this study (57.7% females, 42.3% males). Only 28.0% used daily controller medications; 1,287 (39.7%) patients were not currently on inhaled corticosteroids. Acute upper airway infection was the most common trigger of exacerbation (42.3%). Patients with severe to life-threatening exacerbation tended to have a longer disease course, a smoking history, and had comorbidities such as hypertension, chronic obstructive pulmonary disease (COPD), and food allergy. The multivariate analysis showed that smoking history, comorbidities of hypertension, COPD, and food allergy were independent risk factors for more severe exacerbation. The number of patients hospitalized for asthma exacerbation varied with seasons, peaking in March and September. Eight patients died during the study period (mortality 0.25%). Conclusions: Despite enhanced education on asthma self-management in China during recent years, few patients were using daily controller medications before the onset of their exacerbation, indicating that more educational efforts and considerations are needed. The findings of this study may improve our understanding of hospital admission for asthma exacerbation in mainland China and provide evidence for decision-making.

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