Experimental investigation on a freestanding bridge tower under wind and wave loads

Xiaodong Bai,Anxin Guo,Hao Liu,Wenli Chen,Gao Liu,Tianchen Liu,Shangyou Chen,Hui Li 국제구조공학회 2016 Structural Engineering and Mechanics, An Int'l Jou Vol.57 No.5

Long-span cross-strait bridges extending into deep-sea waters are exposed to complex marine environments. During the construction stage, the flexible freestanding bridge towers are more vulnerable to environmental loads imposed by wind and wave loads. This paper presents an experimental investigation on the dynamic responses of a 389-m-high freestanding bridge tower model in a test facility with a wind tunnel and a wave flume. An elastic bridge model with a geometric scale of 1:150 was designed based on Froude similarity and was tested under wind-only, wave-only and wind-wave combined conditions. The dynamic responses obtained from the tests indicate that large deformation under resonant sea states could be a structural challenge. The dominant role of the wind loads and the wave loads change according to the sea states. The joint wind and wave loads have complex effects on the dynamic responses of the structure, depending on the approaching direction angle and the fluid-induced vibration mechanisms of the waves and wind

Influences of the Filter Effect on Pulse Splitting in Passively Mode-Locked Fiber Laser with Positive Dispersion Cavity

Xiaodong Chen 한국광학회 2015 Current Optics and Photonics Vol.19 No.2

Based on the extended nonlinear Schrödinger equation, the influences of the filter effect on pulse splittingin a passively mode-locked erbium-doped fiber laser with positive dispersion cavity are investigatedtheoretically. Numerical results show that, as the bandwidth of the spectral filter decreases, the nonlinearchirp appended to the pulse increases under the combined action of the filter effect of the super-Gaussianspectral filter and the self-phase modulation effect. On further decreasing the bandwidth, the wave breakingof the pulse takes place. In addition, by varying the pump power of the laser or the profile of the spectralfilter, the influences of the filter effect on pulse splitting also change accordingly

Optical Super-Resolution Imaging of Surface Reactions

Chen, Tao,Dong, Bin,Chen, Kuangcai,Zhao, Fei,Cheng, Xiaodong,Ma, Changbei,Lee, Seungah,Zhang, Peng,Kang, Seong Ho,Ha, Ji Won,Xu, Weilin,Fang, Ning American Chemical Society 2017 Chemical reviews Vol.117 No.11

<P>Optical super-resolution imaging has gained momentum in investigations of heterogeneous and homogeneous chemical reactions at the single-molecule level. Thanks to its exceptional spatial resolution and ability to monitor dynamic systems, much detailed information on single-molecule reaction/adsorption processes and single-particle catalytic processes has been revealed, including chemical kinetics and reaction dynamics; active-site distributions on single-particle surfaces; and size-, shape-, and facet-dependent catalytic activities of individual nanocatalysts. In this review, we provide an overview of recent advances in super-resolution chemical imaging of surface reactions.</P>

Research on Operation Risk and Perceived Physical Condition of Old People : an Empirical Analysis based on Online Follow-Up Survey

Long Xiaodong,Chen Liang,Wang Yuefeng,,Tao Ganchen,Chen Yuanping 보안공학연구지원센터 2015 International Journal of Smart Home Vol.9 No.9

With the development of Internet, the mass media of health management have brought great change to the previous health management model. Based on big data technology and intelligence, new technology allows doctors to make more detailed tracking investigation for the elderly. In this paper, we collected data from 561 senior citizens by using online follow-up survey, and find out the influencing factors related to perceived physical condition. The result shows that the score of the perceived physical condition is 72.91 as compared to gender (T=4.032,P=0.045), age group(T=35.561,P=0.000), educational level (T=15.116, P=0.000), monthly income (T=2.800,P=0.039), marital status (T=15.458,P=0.000), self-care ability (T=49.675,P=0.000), place of abode (T=21.127,P=0.000), previous profession (T=10.030, P=0.000), type of registered permanent residence(T=11.542,P=0.001), chronic disease (T=107.02,P=0.000).

Physically-Based Constitutive Modelling of As-Cast CL70 Steel for Hot Deformation

Fei Chen,Xiaodong Zhao,Jinyu Ren,Huiqin Chen,Xiaofeng Zhang 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.6

In order to conduct numerical simulation of plasticity forming and confirm the processing parameters of heat deformationfor as-cast CL70 steel, the hot deformation behaviors of as-cast CL70 steel were studied by isothermal compression testswhich used a Gleeble-1500D thermal mechanical simulation tester for the deformation temperatures ranging from 1173 to1523 K and the strain rates ranging from 0.001 to 1 s−1. Flow stress curves of the steel were obtained under high temperature. The flow stress constitutive models of the work hardening-dynamical recovery period and dynamical recrystallizationperiod were established for as-cast CL70 steel. In work hardening-dynamic recovery period, the flow stress was predicted byemploying the evolution rule of dislocation density in the constitutive model. In dynamic recrystallization period, the flowstress after the critical strain was predicted by employing the dynamic recrystallization kinetics in the constitutive model. To improve the prediction accuracy of the model, the dynamic recovery coefficient is modified in the traditional physicallybasedconstitutive model. The results indicate that the proposed physically-based constitutive model has high accuracy inpredicting the flow stress under hot deformation for as-cast CL70 steel.

IL28B Is Associated with Outcomes of Chronic HBV Infection

Xiaodong Shi,Junqi Niu,Xiumei Chi,Yu Pan,Yanhang Gao,Wanyu Li,Chen Yang,Jin Zhong,Damo Xu,Manna Zhang,Gerald Minuk,Jing Jiang 연세대학교의과대학 2015 Yonsei medical journal Vol.56 No.3

Purpose: The role of IL28B gene variants and expression in hepatitis B virus (HBV) infections are not well understood. Here, we evaluated whether IL28B gene expression and rs12979860 variations are associated with HBV outcomes. Materialsand Methods: IL28B genetic variations (rs12979860) were genotyped by pyrosequencingof DNA samples from 137 individuals with chronic HBV infection [50 inactive carriers (IC), 34 chronic hepatitis B (CHB), 27 cirrhosis, 26 hepatocellular carcinoma (HCC)], and 19 healthy controls. IL28A/B mRNA expression in peripheralblood mononuclear cells was determined by qRT-PCR, and serum IL28B proteinwas measured by ELISA. Results: Patients with IL28B C/C genotype had greater IL28A/B mRNA expression and higher IL28B protein levels than C/T patients. Within the various disease stages, compared to IC and healthy controls, IL28B expression was reduced in the CHB, cirrhosis, and HCC cohorts (CHB vs. IC, p=0.02; cirrhosis vs. IC, p=0.01; HCC vs. IC, p=0.001; CHB vs. controls, p<0.01; cirrhosis vs. controls, p<0.01; HCC vs. controls, p<0.01). When stratified with respect to serum HBV markers in the IC and CHB cohorts, IL28B mRNA and protein levels were higher in HBeAg-positive than negative individuals (p=0.01). Logistic regression analysis revealed that factors associated with high IL28B proteinlevels were C/C versus C/T genotype [p=0.016, odds ratio (OR)=0.25, 95% confidence interval (CI)=0.08‒0.78], high alanine aminotransferase values (p<0.001, OR=8.02, 95% CI=2.64‒24.4), and the IC stage of HBV infection (p<0.001). Conclusion: Our data suggest that IL28B genetic variations may play an important role in long-term development of disease in chronic HBV infections.

Preclinical investigation of artesunate as a therapeutic agent for hepatocellular carcinoma via impairment of glucosylceramidase-mediated autophagic degradation

Chen Wenjia,Ma Zhaochen,Yu Lingxiang,MAO Xia,Ma Nan,Guo Xiaodong,Yin Xiaoli,Jiang Funeng,Wang Qian,Wang Jigang,Fang Mingliang,Lin Na,Zhang Yanqiong 생화학분자생물학회 2022 Experimental and molecular medicine Vol.54 No.-

Artesunate (ART) has been indicated as a candidate drug for hepatocellular carcinoma (HCC). Glucosylceramidase (GBA) is required for autophagic degradation. Whether ART regulates autophagic flux by targeting GBA in HCC remains to be defined. Herein, our data demonstrated that the dramatic overexpression of GBA was significantly associated with aggressive progression and short overall survival times in HCC. Subsequent experiments revealed an association between autophagic activity and GBA expression in clinical HCC samples, tumor tissues from a rat model of inflammation-induced HCC and an orthotopic mouse model, and human HCC cell lines. Interestingly, probe labeling identified GBA as an ART target, which was further verified by both a glutathione-S-transferase pulldown assay and surface plasmon resonance analysis. The elevated protein expression of LC3B, the increased numbers of GFP-LC3B puncta and double-membrane vacuoles, and the enhanced expression of SQSTM1/p62 indicated that the degradation of autophagosomes in HCC cells was inhibited by ART treatment. Both the in vitro and in vivo data revealed that autophagosome accumulation through targeting of GBA was responsible for the anti-HCC effects of ART. In summary, this preclinical study identified GBA as one of the direct targets of ART, which may have promising potential to inhibit lysosomal autophagy for HCC therapy.

The 16-year experience in treating low-risk gestational trophoblastic neoplasia patients with failed primary methotrexate chemotherapy

Xiaodong Wu,Jiale Qin,Tao Shen,Weidong Fei,Lili Chen,Xing Xie,Weiguo Lu 대한부인종양학회 2020 Journal of Gynecologic Oncology Vol.31 No.4

Objective: To assess the outcomes and toxic effects of 5-day actinomycin D (Act-D) salvagetherapy and to explore the predictors of Act-D resistance in patients with low-risk gestationaltrophoblastic neoplasia (GTN)who failed 5-day methotrexate (MTX) chemotherapy. Methods: This retrospective study analyzed patients with low-risk GTN administered Act-Dsalvage therapy after failing MTX chemotherapy at Women's Hospital, School of MedicineZhejiang University between January 2000 and December 2015. The clinical parameters ofthese patients were collected and analyzed. Results: The final analysis included 89 cases. Of these, 73 cases (82.02%) responded tosalvage Act-D. The remaining 16 resistant cases were switched to etoposide, MTX, Act-D/cyclophosphamide, and vincristine chemotherapy and achieved complete remission. Serumhuman chorionic gonadotrophin levels before Act-D salvage therapy (hCGAct-D)in the Act-D resistant cases were significantly higher than those in the Act-D responders (median 605 vs. 103 IU/L, p=0.009). However, the range of hCGAct-D values in Act-D responders was wider thanthat in Act-D-resistant cases (5.76–16,664 IU/L vs. 11.43–6,732 IU/L). Thus, assigning a generalcut-off value was difficult considering the individual setting. Except for 2 cases requiring othersalvage regimens due to Act-D toxicity, 97.80% of cases (89/91) tolerated the toxicity. During atleast 1-year follow-up, the survival rate was 100.00% and no case developed recurrence. Conclusion: Based on the good therapeutic effect and tolerable toxicity, we recommendAct-D salvage therapy for all patients with low-risk GTN who fail primary MTX chemotherapy. The higher serum hCG levels before Act-D salvage therapy may be associated with resistanceto this treatment.

Hypoxic pancreatic cancer derived exosomal MiR-30b-5p promotes tumor angiogenesis by inhibiting GJA1 expression

Xiaodong TIAN,Kai CHEN,Yinmo YANG 한국간담췌외과학회 2022 Annals of hepato-biliary-pancreatic surgery Vol.26 No.-

New De-excitation Method for Large Hydraulic Generator

Chen, Xianming,Wang, Wei,Lu, Hongshui,Liu, Guohua,Zhu, Xiaodong The Korean Institute of Electrical Engineers 2011 The Journal of International Council on Electrical Vol.1 No.2

The requirement for arc voltage during the opening of a field breaker for large hydraulic generator increases when de-excitation (DE) is performed with a varistor parallel connected to field wingding. In fact, E.M.F of the field winding is required to be higher than the varistor threshold voltage during opening of field breaker. In this paper, the principle of DE with capacitors is introduced. The high voltage produced during DE by the R,L,C series oscillation is used to force the varistor into operation which decreases the opening arc voltage requirement of the field breaker. A simulation is completed to confirm the proper operation of the new DE approach.