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SYNTHESIS OF NOVEL HYDROPHILIC BIODEGRADABLE POLYESTER WITH FUNCTIONALIZED SIDE CHAIN GROUPS

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Chinese Journal of Polymer Science 2001年第5期19卷 509-516页

作者： Ji-yuan Yang Jian Yu Huai-zhong Pan zhong-wei gu wei-xiao Cao Xin-de Feng Department of Polymer Science and Engineering Peking University Beijing 100871, China National Research Institute for Family Planning Beijing 100081, China Dept. of Poly. Sci. and Engineering Peking University Beijing 100871 China Natl. Res. Inst. for Family Planning Beijing 100081 China

A substituted glycolide, 3-benzyloxymethyl-1,4-dioxane-2,5-dione, was synthesized. It is a suitable precursor for the preparation of a new hydrophilic biodegradable poly(a-hydroxy acid). The polymerizations were carried out in bulk in the presence of Sn(Oct)(2) at 120-140 degreesC. The resulting polymers were subjected to hydrogenolysis with a Pd/C catalyst in a mixed solvent to remove the protecting benzyl groups. A novel poly(a-hydroxy acid) with pendant hydroxy groups was obtained. The hydrophilicity of the resulting polymer was evaluated preliminarily.

关键词： biodegradable polyester hydrophilicity functional pendant group

Primary and secondary postoperative hemorrhage in pediatric tonsillectomy

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World Journal of Clinical Cases 2021年第7期9卷 1543-1553页

作者： Bin Xu Hai-Yan Jin Ke Wu Cao Chen Li Li Yang Zhang wei-zhong gu Chao Chen Department of Otorhinolaryngology-Head and Neck Surgery The Children's HospitalZhejiang University School of MedicineNational Clinical Research Center for Child HealthNational Children's Regional Medical CenterHangzhou 310052Zhejiang ProvinceChina Department of Anesthesiology The Children's HospitalZhejiang University School of MedicineNational Clinical Research Center for Child HealthNational Children's Regional Medical CenterHangzhou 310052Zhejiang ProvinceChina Department of Operating Room The Children's HospitalZhejiang University School of MedicineNational Clinical Research Center for Child HealthNational Children's Regional Medical CenterHangzhou 310052Zhejiang ProvinceChina Department of Pathology The Children's HospitalZhejiang University School of MedicineNational Clinical Research Center for Child HealthNational Children's Regional Medical CenterHangzhou 310052Zhejiang ProvinceChina Department of Radiology The Children's HospitalZhejiang University School of MedicineNational Clinical Research Center for Child HealthNational Children's Regional Medical CenterHangzhou 310052Zhejiang ProvinceChina

Tonsillectomy is the most common procedure for treatment of pediatric recurrent acute tonsillitis and tonsillar enlargement that contributes to obstructive sleep apnea hypopnea *** hemorrhage of tonsillectomy is a lifethreatening *** To identify the risk factors that may contribute to primary and secondary postoperative hemorrhage in pediatric *** The clinical data from 5015 children,3443 males and 1572 females,aged 1.92-17.08 years,with recurrent tonsillitis and/or tonsil hypertrophy who underwent tonsillectomy in our hospital from January 2009 to December 2018 were retrospectively *** variables including sex,age,time of onset,diagnosis,method of tonsillectomy,experience of surgeon,time when the surgery started and monthly average air temperature were *** patients with postoperative hemorrhage were classied into two groups,the primary bleeding group and the secondary bleeding group,and their characteristics were compared with those of the nonbleeding group *** analysis was performed by chi-square test with SPSS *** Ninety-two patients had post-tonsillectomy hemorrhage,and the incidence rate of post-tonsillectomy hemorrhage was 1.83%.The mean age was 5.75 *** of primary hemorrhage accounted for approximately 33.70%(31/92),and cases of secondary hemorrhage occurred in 66.30%(61/92).The rate of reoperation for bleeding was 0.92%,and the rate of rehospitalization for bleeding was 0.88%in all *** hemostasis surgery was performed in 6.52%(3/46)of *** method of tonsillectomy(coblation tonsillectomy)and experience of the surgeon(junior surgeon with less than 5 years of experience)were significantly associated with primary hemorrhage(χ^(2)=5.830,P=0.016,χ^(2)=6.621,P=0.010,respectively).Age(over 6 years old)and time of onset(more than a 1-year history)were significantly associated with secondary hemorrhage(χ^(2)=15.242,P=0.000,χ^(2)=4.293,P=0.038,

关键词： Postoperative hemorrhage Tonsillitis Sleep apnea Obstructive Tonsillectomy Child

Design, performance and application of a line-imaging velocity interferometer system for any reflector coupled with a streaked optical pyrometer system at the Shenguang-Ⅱ upgrade laser facility

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High Power Laser Science and Engineering 2024年第1期12卷 52-59页

作者： Dawei Yuan Shaojun Wang Huigang wei Haochen gu Yu Dai Jiayong zhong Yutong Li Gang Zhao Jie Zhang Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijingChina Institute of Frontiers in Astronomy and Astrophysics of Beijing Normal University BeijingChina Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijingChina Key Laboratory for Laser Plasmas(MOE)and School of Physics and Astronomy Shanghai Jiao Tong UniversityShanghaiChina Department of Astronomy Beijing Normal UniversityBeijingChina Collaborative Innovation Center of IFSA Shanghai Jiao Tong UniversityShanghaiChina School of Physical Sciences University of Chinese Academy of SciencesBeijingChina Songshan Lake Materials Laboratory DongguanChina

The velocity interferometer system for any reflector(VISAR) coupled with a streaked optical pyrometer(SOP) system is used as a diagnostic tool in inertial confinement fusion(ICF) experiments involving equations of state and shock *** validate the process of adiabatically compressing the fuel shell through precise tuning of shocks in experimental campaigns for the double-cone ignition(DCI) scheme of ICF, a compact line-imaging VISAR with an SOP system is designed and implemented at the Shenguang-II upgrade laser facility. The temporal and spatial resolutions of the system are better than 30 ps and 7 μm, respectively. An illumination lens is used to adjust the lighting spot size matching with the target size. A polarization beam splitter and λ/4 waveplate are used to increase the transmission efficiency of our system. The VISAR and SOP work at 660 and 450 nm, respectively, to differentiate the signals from the scattered lights of the drive lasers. The VISAR can measure the shock velocity. At the same time, the SOP system can give the shock timing and relative strength. This system has been used in different DCI campaigns, where the generation and propagation processes of multi-shock are carefully diagnosed.

关键词： double-cone ignition streaked optical pyrometer velocity interferometer system for any reflector

Association of T-helper cell cytokine level with age in patients with biliary atresia: a preliminary study

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World Journal of Pediatrics 2018年第4期14卷 404-409页

作者： Fu-Bang Li Xiao-Li Shu wei-zhong gu Xiao-Xia Zhao Shou-Jiang Huang Hong Zhao Ke-Rong Peng Jin-Fa Tou Department of Gastroenterology Children's HospitalZhejiang University School of MedicineHangzhouChina Laboratory of Gastroenterology Children's HospitalZhejiang University School of MedicineHangzhouChina Department of Pathology Children's HospitalZhejiang University School of MedicineHangzhouChina Department of General Surgery Children's HospitalZhejiang University School of MedicineHangzhouChina

Background The pathogenesis of biliary atresia (BA) is associated with an inflammatory process involving the biliary tree. This study aimed to investigate the association of T-helper cell cytokine levels with age in patients with BA. Methods Twenty-eight patients with BA were divided into three groups according to their age (< 2 months, 2–3 months, and ≥ 3 months). All the patients underwent Kasai portoenterostomy. Blood samples were collected from the patients pre-operatively, and the liver tissue specimens were obtained during surgery. We detected serum levels of interleukin (IL)-1β, IL-12p70, interferon (IFN)-γ, IL-6, IL-10, and transforming growth factor (TGF)-β1 and liver expression of IL-1β, IL-6, and TGF-β1. Results The serum levels of IL-1β, IL-12p70, IL-6, and IL-10 in patients aged ≥ 3 months were significantly higher than those in patients aged < 2 months. There were no significant age-related differences in the IL-1β, IL-6 and TGF-β1 expres-sion levels in the liver tissue of patients with BA. Conclusions The serum levels of IL-1β, IL-6, IL-10 and IL-12p70 showed significant age-related differences in patients with BA. Interpretation of the role of cytokines in BA needs to take patient's age into consideration.

关键词： Biliary atresia Cytokines Pathogenesis T-helper cell

COPOLYMERIZATION AND DETERMINATION OF MONOMER REACTIVITY RATIOS OF DL-LACTIDE WITH 3-BENZYLOXYMETHYL-1,4-DIOXANE-2,5-DIONE

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Chinese Journal of Polymer Science 2002年第5期20卷 413-417页

作者： Ji-yuan Yang Jian Yu Mei Li zhong-wei gu Xin-de Feng Department of Polymer Science and Engineering Peking University Beijing 100871, China National Research Institute for Family Planning Beijing 100081, China Department of Polymer Science and Engineering Peking University 北京 100871 National Research Institute for Family Planning 北京 100081

The copolymerization of DL-LA and 3-BMG was carried out in bulk with stannous 2-ethythexanoate as the catalyst. A series of copolymers with pendant protected groups were obtained and characterized by H-1-NMR and GPC analysis. The monomer reactivity ratios were evaluated by the Fineman-Ross method and the Kelen-Tudos method and found to be r(BMG)=1.96 and r(LA)=0.37, respectively.

关键词： 3-benzyloxymethyl 1,4-dioxane-2,5-dione DL-lactide reactivity ratios

Dark Localized Waves in Shallow Waters:Analysis within an Extended Boussinesq System

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Chinese Physics Letters 2024年第4期41卷 32-37页

作者： Zhengping Yang wei-Ping zhong Milivoj Belic Department of Medical Science Shunde PolytechnicShunde 528300China Department of Electronic Engineering Shunde PolytechnicShunde 528300China Division of Arts and Sciences Texas A&M University at Qatar23874 DohaQatar

We study dark localized waves within a nonlinear system based on the Boussinesq approximation,describing the dynamics of shallow water *** symbolic calculus,we apply the Hirota bilinear method to transform an extended Boussinesq system into a bilinear form,and then use the multiple rogue wave method to obtain its dark rational *** the first-and second-order dark solutions,we examine the conditions under which these localized solutions exist and their spatiotemporal *** the selection of various parameters and by utilizing different visualization techniques(intensity distributions and contour plots),we explore the dynamical properties of dark solutions found:in particular,the first-and second-order dark rogue *** also explore the methods of their *** findings presented here not only deepen the understanding of physical phenomena described by the(1+1)-dimensional Boussinesq equation,but also expand avenues for further *** method can be extended to other nonlinear systems,to conceivably obtain higher-order dark rogue waves.

关键词： Boussinesq bilinear nonlinear

Dynamic Simulation of Distribution Networks Using Multi-stage Discontinuous Galerkin Method

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 185-196页

作者： Ruizhi Yu wei gu weiqi Liu Peixin Li wei Liu School of Electrical Engineering Southeast UniversityNanjing 210096China. the School of Electrical Engineering Southeast UniversityNanjing 210096China School of Automation Nanjing University of Science and TechnologyNanjing 210094China

Dynamic simulation plays a fundamental role in security evaluation of distribution networks(DNs).However,the strong stiffness and non-linearity of distributed generation(DG)models in DNs bring about burdensome computation and noteworthy instability on traditional methods which hampers the rapid response of simulation ***,a novel L-stable approximate analytical method with high accuracy is proposed to handle these *** method referred to as multistage discontinuous Galerkin method(MDGM),first derives approximate analytical solutions(AASs)of state variables which are explicit symbolic expressions concerning system ***,in each time window,it substitutes values for symbolic variables and trajectories of state variables are obtained *** paper applies MDGM to DG models to derive ***-truncation-error-based variable step size strategy is also developed to further improve simulation *** addition,this paper establishes detailed MDGM-based dynamic simulation *** case studies on a numerical problem,a modified 33-bus system and a practical large-scale DN,it can be seen that proposed method demonstrates fast and dependable performance compared with the traditional trapezoidal method.

关键词： Approximate analytical method distribution network distributed generation dynamic simulation multi-stage discontinuous Galerkin method variable step size

Research on concrete structure defect repair based on three-dimensional printing

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Frontiers of Structural and Civil Engineering 2024年第5期18卷 731-742页

作者： Yang gu wei LI Xupeng YAO guangjun LIU School of Mechanical Engineering Tongji UniversityShanghai 201804China College of Civil Engineering Tongji UniversityShanghai 200092China Shanghai Engineering Research Center for Safety Intelligent Control of Building Machinery Shanghai 200032China

Quality assurance and maintenance play a crucial role in engineering construction,as they have a significant impact on project *** common issue in concrete structures is the presence of *** enhance the automation level of concrete defect repairs,this study proposes a computer vision-based robotic system,which is based on three-dimensional(3D)printing technology to repair *** system integrates multiple sensors such as light detection and ranging(LiDAR)and *** is utilized to model concrete pipelines and obtain geometric parameters regarding their ***,a convolutional neural network(CNN)is employed with a depth camera to locate defects in concrete ***,a method for coordinate transformation is presented to convert the obtained coordinates into executable ones for a robotic ***,the feasibility of this concrete defect repair method is validated through simulation and experiments.

关键词： concrete defect detection 3D printing deep learning point cloud data

H∞ Robustness for Distributed Control in Autonomous Microgrids Considering Cyber Disturbances

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 696-706页

作者： Ge Cao guannan Lou wei gu Lina Sheng School of Electrical Engineering Southeast UniversityNanjing 210096China

The physical connections and logical relationships between microgrids and communication networks allow microgrids to develop into typical cyber-physical systems(CPSs).With the extensive use of open communication mechanisms,the impact of cyber disturbances in public communication networks cannot be *** this paper,a parameter optimal method for a distributed secondary controller based on the robust control theory and consensus algorithm is presented to enhance the robustness of a secondary control system under data disturbance,parameter perturbation,and time ***,a distributed secondary control strategy of microgrids is demonstrated that coordinates frequency and voltage restoration and power ***,considering the impact of cyber events on the secondary control,a distributed robust controller gain design method is proposed to satisfy the H∞ performance *** solution of the distributed robust control is transformed into a linear matrix in equation problem and latency margin is simultaneously ***,a test microgrid CPS is simulated with and without time delay to investigate the impact of cyber events on system operational states and the effectiveness and robustness of the proposed method.

关键词： Cyber disturbance cyber-physical lsystem distributed control microgrid robust H∞control