Swept-sine integration method for complex amplitude extraction of sweptsine signal

Wei Zheng,Xuli Cui,Huaihai Chen,Ronghui Zheng 대한기계학회 2020 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.34 No.12

Swept-sine vibration test plays a significant role in product validations. As its basic step, the accuracy and efficiency of complex amplitude (which includes the amplitude and phase information of swept-sine signal) extraction have an important impact on the performance of swept-sine vibration test. In order to improve the efficiency while ensuring its accuracy, a swept-sine integration method is proposed. The proposed swept-sine integration method, which is inspired by tracking filter method and tracking integration method, utilizes a weighted integral process to extract the complex amplitude. A numeral example is presented to compare the performance of the proposed method with several other methods for complex amplitude extraction which are also reviewed in this paper. By comparing the results of the numerical example, some light is shed on the strength of the method proposed. Afterwards, the swept-sine integration method is applied in a real test, further validating the appliance value of this method.

Study on the transient flow induced by the windbreak transition regions in a railway subject to crosswinds

Zheng-Wei Chen,Syeda Anam Hashmi,Tanghong Liu,Wenhui Li,Zhuang Sun,Dongrun Liu,Hassan Hemida,Hong-Kang Liu 한국풍공학회 2022 Wind and Structures, An International Journal (WAS Vol.35 No.5

Due to the complex terrain around high-speed railways, the windbreaks were established along different landforms, resulting in irregular windbreak transition regions between different subgrade infrastructures (flat ground, cutting, embankment, etc). In this paper, the effect of a windbreak transition on the wind flow around railways subjected to crosswinds was studied. Wind tunnel testing was conducted to study the wind speed change around a windbreak transition on flat ground with a uniform wind speed inflow, and the collected data were used to validate a numerical simulation based on a detached eddy simulation method. The validated numerical method was then used to investigate the effect of the windbreak transition from the flat ground to cutting (the “cutting” is a railway subgrade type formed by digging down from the original ground) for three different wind incidence angles of 90º, 75º, and 105º. The deterioration mechanism of the flow fields and the reasons behind the occurrence of the peak wind velocities were explained in detail. The results showed that for the windbreak transition on flat ground, the impact was small. For the transition from the flat ground to the cutting, the influence was relatively large. The significant increase in the wind speeds was due to the right-angle structure of the windbreak transition, which resulted in sudden changes of the wind velocity as well as the direction. In addition, the height mismatch in the transition region worsened the protective effect of a typical windbreak.

Primary Aldosteronism and Cerebrovascular Diseases

Zheng-Wei Chen,Chi-Sheng Hung,Vin-Cent Wu,Yen-Hung Lin,TAIPAI study group 대한내분비학회 2018 Endocrinology and metabolism Vol.33 No.4

As diagnostic techniques have advanced, primary aldosteronism (PA) has emerged as the most common cause of secondary hypertension. The excess of aldosterone caused by PA resulted in not only cardiovascular complications, including coronary artery disease,myocardial infarction, arrhythmia, and heart failure, but also cerebrovascular complications, such as stroke and transient ischemicattack. Moreover, PA is associated more closely with these conditions than is essential hypertension. In this review, we present up-todate findings on the association between PA and cerebrovascular diseases.

The Phytotoxic Effects of Selenium–Mercury Interactions on Root Growth in Brassica rapa (LvLing)

Zhi-Wei Bian,Jian Chen,Hui Li,Dan-Dan Liu,Li-Fei Yang,Yue-Lin Zhu,Wen-Li Zhu,Wei Liu,Zheng-Zheng Ying 한국원예학회 2016 Horticulture, Environment, and Biotechnology Vol.57 No.3

Rapid industrial and agricultural development has dramatically increased the emission of selenium (Se) and mercury (Hg) into the environment. Combined soil pollution by Se and Hg poses a potential threat to crop production. However, no toxic effects of Hg–Se interactions on plants have been reported previously. In this study, we investigated the effects of Hg–Se interactions on biochemical and physiological indices in the roots of Brassica rapa (LvLing). Seedlings were treated hydroponically with solutions of mercury chloride (1 μM), sodium selenite (4 μM), or a combination of the two. Combined Hg+Se treatment significantly inhibited root growth, reduced root biomass, and enhanced reactive oxygen species (ROS) and malondialdehyde accumulation and led to a loss of plasma membrane integrity. The combined treatment increased glutathione peroxidase, glutathione S-transferase, and peroxidase activity, reduced superoxide dismutase activity, and had no effect on catalase activity. In addition, we detected increased glutathione concentrations in root tips and reduced ascorbic acid concentrations in the presence of Hg+Se relative to individual treatments with these elements. Thus, Hg–Se interactions enhanced oxidative injury, cell death, and phytotoxicity in B. rapa roots.

Study of the Band-gap Structure of a 1D-photonic Crystal by Using Different Numerical Approaches

Liang-Yao Chen,Jian-Bo Chen,Yue-Rui Chen,Yan Shen,Wei-Xi Zhou,Jiu-Chun Ren,Yu-Xiang Zheng 한국물리학회 2010 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.56 No.4

Comparative studies between the transfer matrices method (TMM) and plane wave method (PWM) approaches have been performed on 1D photonics crystal under different conditions to show the differences between these two kinds of calculations. TMM is suitable for the design of 1D photonic crystal device with high precision and is in good agreement with experimental results, but is not suitable for the 2D and 3D photonic structures which are limited by the complicated boundary conditions at micro interfaces. The result based on the PWM approach to deal approximately with the photonic structure in approximation has not yet been strictly verified by experiment, not even for 1D photonic crystal structures. More efforts will be required to explore its validation under all physical conditions to enhance its application.

Pancreatic Cancer Incidence and Mortality Patterns in China, 2009

Chen, Wan-Qing,Liang, Di,Zhang, Si-Wei,Zheng, Rou-Shou,He, Yu-Tong Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.12

Objective: To estimate the incidence and mortality rates for pancreatic cancer in China. Methods: After checking and reviewing the cancer registry data in 2009 from 72 cancer registry centers, we divided cancer registry areas into urban and rural areas. Incidence/mortality rates, age-specific incidence/mortality rates, age-standardized incidence/mortality rates, proportions, and cumulative incidence/mortality rates for pancreatic cancer were calculated. Results: The total number of newly diagnosed pancreatic cancer cases and deaths in 2009 were 6,220 and 5,650, respectively. The crude incidence rate in all cancer registry areas was 7.28/100,000 (males 8.24, females 6.29). The age-standardized incidence rate by Chinese standard population (ASR) was 3.35/100,000, with ranking at 7th among all cancers. Pancreatic cancer incidence rate was 8.19/100,000 in urban areas whereas it was 5.41/100 000 in rural areas. Cancer mortality rate in all cancer registry areas was 6.61/100,000 (males 7.45; females 5.75), with ranking at 6th among all cancers, and 7.42/100 000 in urban but 4.94/100000 in rural areas. Conclusions: Pancreatic cancer incidence and mortality rates have shown a gradual increase in China. Owing to the difficulty of early diagnosis, identification of high-risk population and modification of risk factors are important to reduce the burden of pancreatic cancer.

Endophytic fungi harbored in Panax notoginseng: diversity and potential as biological control agents against host plant pathogens of root-rot disease

Zheng, You-Kun,Miao, Cui-Ping,Chen, Hua-Hong,Huang, Fang-Fang,Xia, Yu-Mei,Chen, You-Wei,Zhao, Li-Xing The Korean Society of Ginseng 2017 Journal of Ginseng Research Vol.41 No.3

Background: Endophytic fungi play an important role in balancing the ecosystem and boosting host growth. In the present study, we investigated the endophytic fungal diversity of healthy Panax notoginseng and evaluated its potential antimicrobial activity against five major phytopathogens causing root-rot of P. notoginseng. Methods: A culture-dependent technique, combining morphological and molecular methods, was used to analyze endophytic fungal diversity. A double-layer agar technique was used to challenge the phytopathogens of P. notoginseng. Results: A total of 89 fungi were obtained from the roots, stems, leaves, and seeds of P. notoginseng, and 41 isolates representing different morphotypes were selected for taxonomic characterization. The fungal isolates belonged to Ascomycota (96.6%) and Zygomycota (3.4%). All isolates were classified to 23 genera and an unknown taxon belonging to Sordariomycetes. The number of isolates obtained from different tissues ranged from 12 to 42 for leaves and roots, respectively. The selected endophytic fungal isolates were challenged by the root-rot pathogens Alternaria panax, Fusarium oxysporum, Fusarium solani, Phoma herbarum, and Mycocentrospora acerina. Twenty-six of the 41 isolates (63.4%) exhibited activity against at least one of the pathogens tested. Conclusion: Our results suggested that P. notoginseng harbors diversified endophytic fungi that would provide a basis for the identification of new bioactive compounds, and for effective biocontrol of notoginseng root rot.

NEW FORM OF INDUSTRIAL FREQUENCY WATTMETER BASED ON DOUBLE THREE SLOPE PRINCIPLE

Wei, Wang Xue,Sheng, Fei Zheng,Chen, Liu Bei,Lin, Wang 대한전자공학회 1992 HICEC:Harbin International Conference on Electroni Vol.1 No.1

This paper proposes a double three slope multiplying A/D converter and introduces the new A/D converter application with sample/hold technique and microprocessor in the field of industrial power measurement. The new A/D converter has low price. The wattmeter based on the new A/D converter and microprocessor now is used, its precision is better than 0.1%.

Serum Anti-Fumarate Hydratase Autoantibody as a Biomarker for Predicting Prognosis of Acute-on-Chronic Liver Failure

Wei Linlin,Wang Ting,Chen Sisi,Liu Yeying,Huang Xueying,Zheng Sujun,Xu Bin,Ren Feng,Liu Mei 거트앤리버 소화기연관학회협의회 2023 Gut and Liver Vol.17 No.5

Background/Aims: To investigate the autoantibody against fumarate hydratase (FH), which is a specific liver failure-associated antigen (LFAA) and determine whether it can be used as a biomarker to evaluate the prognosis of acute-on-chronic liver failure (ACLF). Methods: An immunoproteomic approach was applied to screen specific LFAAs related to differential prognosis of ACLF (n=60). Enzyme-linked immunosorbent assay (ELISA) technology was employed for the validation of the frequency and titer of autoantibodies against FH in ACLF patients with different prognoses (n=82). Moreover, we clarified the expression of autoantibodies against FH in patients with chronic hepatitis B (n=60) and hepatitis B virus-related liver cirrhosis (n=60). The dynamic changes in the titers of autoantibodies against FH were analyzed by sample collection at multiple time points during the clinical course of eight ACLF patients with different prognoses. Results: Ultimately, 15 LFAAs were screened and identified by the immunoproteomic approach. Based on ELISA-based verification, anti-FH/Fumarate hydratase protein autoantibody was chosen to verify its expression in ACLF patients. ACLF patients had a much higher anti-FH autoantibody frequency (76.8%) than patients with liver cirrhosis (10%, p=0.000), patients with chronic hepatitis B (6.7%, p=0.022), and normal humans (0%, p=0.000). More importantly, the frequency and titer of anti-FH protein autoantibodies in the serum of ACLF patients with a good prognosis were much higher than that of patients with a poor prognosis (83.9% vs 61.5%, p=0.019; 1.41±0.85 vs 0.94±0.56, p=0.017, respectively). The titer of anti-FH autoantibodies showed dynamic changes in the clinical course of ACLF. Conclusions: The anti-FH autoantibody in serum may be a potential biomarker for predicting the prognosis of ACLF.

Percutaneous radiologic gastrostomy in patients with amyotrophic lateral sclerosis: A safe and effective technique

Chen Xu,Zheng-Qiang Yang,Sheng Liu,Wei Yang,Hai-Bin Shi,Wei-Zhong Zhou 소화기인터벤션의학회 2021 Gastrointestinal Intervention Vol.10 No.2

Background: Percutaneous radiologic gastrostomy (PRG) was considered as an alternative technique for long-term enteral nutrition, and the current study is aimed to evaluate the feasibility and safety of this technique in patients with amyotrophic lateral sclerosis (ALS) at a single medical center. Methods: From July 2017 to October 2020, a total of 14 patients underwent PRG with ALS were included in this retrospective study with a median age of 64.0 years, and 78.6% were male. The procedure comprised a dilation of the stomach via a nasogastric catheter, followed by puncture and gastrostomy tube placement under fluoroscopic guidance. The technical success rate and clinical outcomes were recorded over 3 months following the procedure. Results: The technical success rate was 100%. During the follow-up period, minor complications were reported in 2 of patients (14.3%) including superficial skin infection and early tube block. Neither major complications nor mortality were observed. Body mass index of the patients increased significantly from 16.4 ± 2.1 kg/m2 to 17.1 ± 2.0 kg/m2 (t = –13.77; P < 0.001), and the albumin level increased significantly from 37.5 ± 2.3 g/L to 41.8 ± 1.6 g/L (t = –8.82, P < 0.001). Conclusion: PRG is a relatively safe and effective method for ALS patients, and deserves widespread clinical acceptance.