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NUMERICAL AND EXPERIMENTAL STUDIES OF INFLUENCE OF THE CAUDAL FIN SHAPE ON THE PROPULSION PERFORMANCE OF A FLAPPING CAUDAL FIN

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Journal of Hydrodynamics 2011年第3期23卷 325-332页

作者： ZHANG xi SU yu-min wang Zhao-li State Key Laboratory of Autonomous Underwater Vehicle Harbin Engineering University Harbin 150001 China

This article presents a comprehensive study of the effects of the caudal fin shape on the propulsion performance of a candal fin in harmonic heaving and pitching. A numerical simulation based on an unsteady panel method was carried out to analyze the hydrodynamic performance of flapping caudal fins of three shapes （the whale caudal fin with the largest projected area, the dolphin caudal fin with the median projected area, and the tuna caudal fin with the smallest projected area）. Then, a series of hydrodynamic experiments for three caudal fin shapes were performed. Both computational and experimental results indicate that the tuna caudal fin produces the highest efficiency. However the mean thrust coefficient of the tuna caudal fin is the smallest. It is found that although the mean thrust coefficient for the tuna caudal fin is not large, the input power of the tuna caudal fin is also quite small. So the tuna caudal fin achieves a high efficiency.

关键词： flapping caudal fin caudal fin shape numerical simulations hydrodynamic experiments hydrodynamic performance

Evaluation on biocompatibility of biomedical polyurethanes with different hard segment contents

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Frontiers of Materials Science 2015年第4期9卷 397-404页

作者： Dai-Wei MA Rong ZHU Yi-yu wang Zong-Rui ZHANG xi n-yu wang State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology Wuhan 430070 China Biomedical Materials and Engineering Research Center of Hubei Province Wuhan University of Technology Wuhan 430070 China

In this paper, polyurethane （PU） materials with different contents of hard segment （20%, 25%, 30%） were prepared based on hexamethylene diisocyanate and polycarbonate diols by solution polymerization. The obtained polycarbonate-urethane （PCU） elastomers were characterized by very good hydrophobic property and excellent resistance to hydrolysis. Hemolysis, recalification time and platelet-rich plasma adhesion were used to evaluate the blood compatibility of the materials. L929 cells cultured with leach liquor of these PU membranes were selected to perform the cytotoxicity experiments. The results indicate that the hemolysis rates of PU membranes are all less than 5%, which can meet the requirement of the national standards for biomaterials. However, compared with 20% and 30% groups, the recalification time of the sample containing 25% hard segment is longer, while the number of platelet adhesion is less. Additionally, cells cultured in the leach liquor of PU membranes with 25% hard segment proliferated relatively more thriving, meaning that this proportion of the material has the lowest cytotoxicity.

关键词： polyurethane (PU) hydrolytic stability blood compatibility cytotoxicity

Learning curves of resection and reconstruction procedures in robotic-assisted pancreatoduodenectomy by a single surgeon:a retrospective cohort study of 160 consecutive cases

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Gastroenterology Report 2023年第1期11卷 424-432页

作者： xi-Tai Huang xi-yu wang Jin-Zhao xie Jian-Peng Cai Wei Chen Liu-Hua Chen xiao-yu Yin Department of Pancreato-Biliary Surgery The First Affiliated HospitalSun Yat-sen UniversityGuangzhouGuangdongP.R.China

Background:Robotic-assisted pancreatoduodenectomy(RPD)has been routinely performed in a few of centers *** study aimed to evaluate the perioperative outcomes and the learning curves of resection and reconstruction procedures in RPD by one single ***:Consecutive patients undergoing RPD by a single surgeon at the First Affiliated Hospital of Sun Yat-sen University(Guangzhou,China)between July 2016 and October 2022 were *** perioperative outcomes and learning curves were retrospectively analysed by using cumulative sum(CUSUM)***:One-hundred and sixty patients were *** to the CUSUM curve,the times of resection and reconstruction procedures were shortened significantly after 30 cases(median,284 vs 195 min;P<0.001)and 45 cases(median,138 vs 120 min;P<0.001),*** estimated intraoperative blood loss(median,100 vs 50 mL;P<0.001)and the incidence of clinically relevant post-operative pancreatic fistula(29.2%vs 12.5%;P=0.035)decreased significantly after 20 and 120 cases,*** were no significant differences in the total number of lymph nodes examined,post-operative major complications,or post-operative length-of-stay between the two ***:Optimization of the resection procedure and the acquisition of visual feedback facilitated the performance of *** was a safe and feasible procedure in the selected patients.

关键词： robotic-assisted surgery pancreatoduodenectomy learning curve outcomes

Evaluating the causal relationship between human blood metabolites and gastroesophageal reflux disease

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World Journal of Gastrointestinal Oncology 2023年第12期15卷 2169-2184页

作者： Jia-Yan Hu Mi Lv Kun-Li Zhang xi-yun Qiao yu-xi wang Feng-yun wang Institute of Digestive Diseases Xiyuan HospitalChina Academy of Chinese Medical SciencesXiyuan HospitalChina Academy of Chinese Medical SciencesBeijing 100091China

BACKGROUND Gastroesophageal reflux disease(GERD)affects approximately 13% of the global ***,the pathogenesis of GERD has not been fully *** development of metabolomics as a branch of systems biology in recent years has opened up new avenues for the investigation of disease *** a powerful statistical tool,Mendelian randomization(MR)is widely used to explore the causal relationship between exposure and *** To analyze of the relationship between 486 blood metabolites and *** Two-sample MR analysis was used to assess the causal relationship between blood metabolites and GERD.A genome-wide association study(GWAS)of 486 metabolites was the exposure,and two different GWAS datasets of GERD were used as endpoints for the base analysis and replication and *** correction is used to determine causal correlation features(P<1.03×10^(-4)).The results were subjected to sensitivity analysis to assess heterogeneity and *** the MR Steiger filtration method to detect whether there is a reverse causal relationship between metabolites and *** addition,metabolic pathway analysis was conducted using the online database based MetaboAnalyst 5.0 *** In MR analysis,four blood metabolites are negatively correlated with GERD:Levulinate(4-oxovalerate),stearate(18:0),adrenate(22:4n6)and ***,we also found a positive correlation between four blood metabolites and GERD:Kynurenine,1-linoleoylglycerophosphoethanolamine,butyrylcarnitine and *** bonferroni correction showed that butyrylcarnitine(odd ratio 1.10,95% confidence interval:1.05-1.16,P=7.71×10^(-5))was the most reliable causal *** addition,one significant pathways,the"glycerophospholipid metabolism"pathway,can be involved in the pathogenesis of *** Our study found through the integration of genomics and metabolomics that butyrylcarnitine may be a potential biomarker for GERD,whic

关键词： Blood metabolites Gastroesophageal reflux disease Mendelian randomization Causality Pathogenesis Biomarkers Metabolic pathway

Therapeutic effect of Qingyi decoction in severe acute pancreatitis-induced intestinal barrier injury

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World Journal of Gastroenterology 2015年第12期21卷 3537-3546页

作者： Jing-Wen Zhang Gui-xin Zhang Hai-Long Chen Ge-Liang Liu Lawrence Owusu yu-xi wang Guan-yu wang Cai-Ming Xu Department of Surgery The First Affiliated Hospital Dalian Medical University Department of Surgery The Second Affiliated Hospital Dalian Medical University

AIM: To investigate the effect of Qingyi decoction onthe expression of secreted phospholipase A2(s PLA2) in intestinal barrier ***: Fifty healthy Sprague-Dawley rats were randomly divided into control, severe acute pancreatitis(SAP), Qingyi decoction-treated(QYT), dexamethasonetreated(DEX), and verapamil-treated(VER) groups. The SAP model was induced by retrograde infusion of 1.5% sodium deoxycholate into the biliopancreatic duct of the rats. All rats were sacrificed 24 h post-SAP induction. Arterial blood, intestine, and pancreas from each rat were harvested for investigations. The levels of serum amylase(AMY) and diamine oxidase(DAO) were determined using biochemical methods, and serum tumor necrosis factor(TNF)-α level was measured by an enzyme linked immunosorbent assay. Pathologic changes in the harvested tissues were investigated by microscopic examination of hematoxylin and eosinstained tissue sections. The expressions of s PLA2 at m RNA and protein levels were detected by reverse transcriptase PCR and Western blot, respectively. A terminal deoxynucleotidyl transferase-mediated d UTP nick-end labeling assay was used to investigate apoptosis of epithelial cells in the intestinal tissues. RESULTS: Compared to the control group, the expression of s PLA2 at both the m RNA and protein levels increased significantly in the SAP group(0.36 ± 0.13 vs 0.90 ± 0.38, and 0.16 ± 0.05 vs 0.64 ± 0.05, respectively; P s < 0.01). The levels of AMY, TNF-α and DAO in serum were also significantly increased(917 ± 62 U/L vs 6870 ± 810 U/L, 59.7 ± 14.3 ng/L vs 180.5 ± 20.1 ng/L, and 10.37 ± 2.44 U/L vs 37.89 ± 5.86 U/L, respectively; P s < 0.01). The apoptosis index of intestinal epithelial cells also differed significantly between the SAP and control rats(0.05 ± 0.02 vs 0.26 ± 0.06; P < 0.01). The serum levels of DAO and TNF-α, and the intestinal apoptosis index significantly correlated with s PLA2 expression in the intestine(r = 0.895, 0.893 and 0.926, respectively; Ps

关键词： Intestinal barrier injury Qingyi decoction Secrete

The Promoting Effect on the Activities ofFe Doped TiO_2 Photocatalysts

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Chemical Research in Chinese Universities 2001年第2期17卷 187-192页

作者： yu xi-bin, wang Gui-hua and LI He-xing (Department of Chemistry, Shanghai Normal University, Shanghai 200234, P. R. China) Shanghai Normal Univ Dept Chem Shanghai 200234 Peoples R China

The particles of titanium-iron (Ti/Fe) complex with different Fe contents were prepared by means of the sol-gel method and used as a photocatalyst. The activity of the catalyst was investi- gated as a function of the Fe content during the liquid-phase oxidation of tetracycline, which showed an enhancement at the low Fe content. The XRD, Raman, XPS, and UV-Vis absorp- tion spectra indicated that the crystalline structure of the Ti/Fe complex particles changed from anatase phase to rutile phase when the Fe content increased. The isolated Fe203, Fe304, FeO species were observed and Fe3+ ions were highly dispersed in the TiO2 matrixes, then Ti-O-Fe species were formed. These species increased the surface defects of the Ti/Fe particles. Also, ac- tive hydroxyl radicals could be generated in the catalytic transformation, which led to the higher activity of the catalyst than bare Ti02 for the degradation of tetracycline.

关键词： Titanium Fe doped photocatalyst Photocatalytic activity Tetracycline

Cytoprotective Mechanism of the Novel Gastric Peptide BPC157 in Gastrointestinal Tract and Cultured Enteric Neurons and Glial Cells

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Neuroscience Bulletin 2019年第1期35卷 167-170页

作者： xi-yu wang Meihua Qu Rui Duan Dengping Shi Ling Jin Jinping Gao Jackie D.Wood Junhua Li Guo-Du wang Basic and Clinical Medical Research Center Jingmen First Hospital Department of Medicine School of Medicine Tulane University Department of Physiology School of Medicine Ohio State University School of Pharmacy Weifang Medical University Department of Gastroenterology and Surgery Jingmen Second Hospital

Dear Editor,Body protection compound (BPC) 157 is a stable gastric pentadecapeptide. Predrag Sikiric’s team has carried out many investigations of its cytoprotective effects in different organs and tissues (1, 2)Their evidence indicates that BPC157 has potent cytoprotection in neural injury and gastrointestinal (GI) ulcers. Nevertheless.

关键词： BPC HT GI Cytoprotective Mechanism of the Novel Gastric Peptide BPC157 in Gastrointestinal Tract and Cultured Enteric Neurons and Glial Cells

Colocated MIMO radar waveform-design based on two-step optimizations in spatial and spectral domains

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Frontiers of Information Technology & Electronic Engineering 2017年第7期18卷 1021-1032页

作者： yu-xi wang Guo-ce HUANG Wei LI Jin-liang LI Information and Navigation College Air Force Engineering University Xi 'an 710077 China

We propose an efficient colocated multiple-input multiple-output radar waveform-design method based on two-step optimizations in the spatial and spectral domains. First, a minimum integrated side-lobe level strategy is adopted to obtain the desired beam pattern with spatial nulling. By recovering the hidden convexity of the resulting fractional quadratically constrained quadratic programming non-convex problem, the global optimal solution can be achieved in polynomial time through a semi- definite relaxation followed by spectral factorization. Second, with the transmit waveforms obtained via spatial optimization, a phase changing diagonal matrix is introduced and optimized via power method-like iterations. Without influencing the shape of the optimized beam pattern, the transmit waveforms are further optimized in the spectral domain, and the desired spectral nulling is formed to avoid radar interference on the overlaid licensed radiators. Finally, the superior performance of the proposed method is demonstrated via numerical results and comparisons with other approaches to waveform design.

关键词： Multiple-input multiple-output (MIMO) radar Waveform design Spectral factorization Fractional quadraticallyconstrained quadratic programming (QCQP)

Involvement of cysteinyl leukotriene signaling in microglial morphological changes and CASP1 expression in vitro

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中国药理学与毒理学杂志 2017年第10期31卷 1028-1029页

作者： yu-xi wang Si-ran ZHANG Xue XU Cheng-tan LI Wei ZHENG Jian-bo ZHAO Yan-fang wang Li-hui ZHANG Department of Pharmacology Hangzhou Key Laboratory of Medical NeurobiologySchool of MedicineHangzhou Normal University Department of Neurology Zhejiang Hospital

OBJECTIVE We have recently reported that cysteinyl leukotriene(Cys LT) signaling plays an important role in microglial interleukin(IL)-1β secretion and subsequent *** present study aimed to examine microglial morphological changes and the upstream molecular underlying IL^(-1)β production in Cys LT receptor agonist leukotriene D4(LTD4)-treated BV2 microglia in *** Twenty-four hours after murine microglial BV2 cells were stimulated with LTD4(1-100 nmol·L^(-1)),the cell proliferation and morphology were *** expression level of cysteinyl aspartate-specific protease 1(CASP1) protein was measured by Western blotin BV2 *** addition,BV2 cells were pretreated with or without CysLT1 receptor antagonist montelukast for 1 h and the effects of monte-lukaston LTD4-stimulated microglial activation and CASP1 expression were *** The number of BV2 cells had an increasing tendency after 24 h treatment with LTD4,but no significant differences were observed between the control and LTD4-treated cells(P>0.05).Under basal and resting conditions,BV2 microglial cells displayed a ramified ***,LTD4 at 100 nmool·L^(-1) drove microglial morphological changes from a ramified towards an amoeboid *** expression of CASP1 protein was significantly upregulated in 100 nmool·L^(-1) LTD4-treated BV2 microglia(P<0.01).Furthermore,pretreatment with CysLT1 receptor antagonist montelukast prevented cell morphological changes and suppressed the increased CASP1 expression in LTD4-treated BV2 cells(P<0.05).CONCLUSION Cys LT receptor agonist LTD4 induces morphological changes and CASP1 expressionin BV2 microglia,which can be inhibited by CysLT1 *** results suggest the involvement of Cys LT signaling in microglial morphological changes and CASP1 expression.

关键词： cysteinyl leukotriene receptor microglia inflammation