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Evaluating effectiveness and safety of combined percutaneous transhepatic gallbladder drainage and laparoscopic cholecystectomy in acute cholecystitis patients:Meta-analysis

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World Journal of Gastrointestinal Surgery 2024年第5期16卷 1407-1419页

作者： Yu li Wei-Ke xiao xiao-jun li Hui-Yuan Dong Department of General Surgery No.942 Hospital of PLAYinchuan 750004Ningxia Hui Autonomous RegionChina

BACKGROUND Acute cholecystitis(AC)is a common disease in general *** cholecystectomy(LC)is widely recognized as the"gold standard"surgical procedure for treating *** low-risk patients without complications,LC is the recommended treatment plan,but there is still controversy regarding the treatment strategy for moderate AC patients,which relies more on the surgeon's experience and the medical platform of the visiting *** transhepatic gallbladder puncture drainage(PTGBD)can effectively alleviate gallbladder inflammation,reduce gallbladder wall edema and adhesion around the gallbladder,and create a"time window"for elective *** To compare the clinical efficacy and safety of LC or PTGBD combined with LC for treating AC patients,providing a theoretical basis for choosing reasonable surgical methods for AC *** In this study,we conducted a clinical investigation regarding the combined use of PTGBD tubes for the treatment of gastric cancer patients with *** performed searches in the following databases:PubMed,Web of Science,EMBASE,Cochrane library,China National Knowledge Infrastructure,and Wanfang *** search encompassed literature published from the inception of these databases to the ***,relevant data were extracted,and a meta-analysis was conducted using RevMan 5.3 *** A comprehensive analysis was conducted,encompassing 24 studies involving a total of 2564 *** patients were categorized into two groups:1371 in the LC group and 1193 in the PTGBD+LC *** outcomes of the meta-analysis revealed noteworthy disparities between the PTGBD+LC group and the LC group in multiple dimensions:(1)Operative time:Mean difference(MD)=17.51,95%CI:9.53-25.49,P<0.01;(2)Conversion to open surgery rate:Odds ratio(OR)=2.95,95%CI:1.90-4.58,P<0.01;(3)Intraoperative bleeding loss:MD=32.27,95%CI:23.03-41.50,P<0.01;(4)Postoperative hospital stay:MD=1.44,95%CI:0.14-2.73,P=0.03;(5)Overall posto

关键词： Acute cholecystitis Laparoscopic cholecystectomy Percutaneous transhepatic gallbladder drainage Metaanalysis Efficacy

STRUCTURE AND PROPERTIES OF PHOSPHROUS-CONTAINING POLY(ARYLETHER KETONE)WITH BISPHENOL-A MOIETY

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Chinese Journal of Polymer Science 2007年第6期25卷 651-655页

作者： Kai-jun li xiao-ting Chen Hao Sun Xu-dong Tang College of Material Science ＆ Chemical Engineering Tianjin University of Science ＆ Techology Tianjin 300457 China

A phosphrous-containing poly（aryl ether ketone） was synthesized derived from bisphenol-A and bis[4-（4- fluorobenzoyl）phenyl] phenyl phosphine oxide （FPPPO） by nucleophilic substitution reaction. The structure of the polymer was characterized by FT-IR, ^1H-NMR and ^31p-NMR. The thermal property of the PAEK was measured by DSC and TGA. The glass transition temperature （Tg） of the polymer was 205℃, and the 5% weight loss temperature under nitrogen was 475℃. Good solubility of the polymer in organic solvents, such as N-methylpyrrolidone, dimethylformamide, dimethylacetamide, dimethylsulfoxide and chloroalkanes was observed, flexible film was obtained from the polymer＇s CH2Cl2 solution. The limiting oxygen index （LOI） of the PAEK was 40, which indicated that organic phosphorus moiety can offer good flame retardant property to the polymer.

关键词： Poly(aryl ether ketone) Bis[4-(4-fluorobenzoyl)phenyl] phenyl phosphine oxide (FPPPO) Nucleophilic substitution reaction Bisphenol-A.

NUMERICAL SIMULATION OF IRREGULAR WAVE-SIMULATING IRREGULAR WAVE TRAIN

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Journal of Hydrodynamics 2010年第4期22卷 537-545页

作者： liANG Xiu-feng YANG Jian-min li jun xiao Long-fei li Xin State Key Laboratory of Ocean Engineering Shanghai Jiao Tong University Shanghai 200030 China

In real sea states,damage incidents on offshore floating structures are not due to the whole time series of wave elevation characterized as statistical one but due to few extreme waves or wave groups in irregular wave ***,using CFD tools to precisely simulate predetermined irregular wave train will lay sound basis for understanding the local characteristic of the flow field and impact loads on offshore floating structures when damage incidents *** this article,the generation of single extreme wave is investigated in a numerical wave ***,experimental irregular wave train is decomposed into certain number of small-amplitude *** Fourier series expansion is performed to determine the amplitude and initial phase angle of each wave component.A hydrodynamic transfer function is used to calculate the amplitude of wave-maker motion associated with each wave *** superposition is carried out on all of the wave-maker motion components to get the final wave-maker *** the wave-maker motion as input,simulation of the single extreme irregular wave train is modeled *** the method is applied to simulating a much more complicated irregular wave *** again main features of the complicated irregular wave train are reproduced compared with experiment carried out in the new deepwater experimental basin at Shanghai Jiao Tong *** the simulation,dynamic mesh method is enabled to model the piston-type wave-maker,the Volume Of Fluid（VOF） method is employed to capture the free surface and a dissipation zone is introduced to deal with wave reflection.

关键词： numerical wave tank irregular wave train Volume of Fluid (VOF) dynamic mesh

KGSR-GG:A Noval Scheme for Dynamic Recommendation

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Computers, Materials & Continua 2022年第12期73卷 5509-5524页

作者： jun-Ping Yao Kai-Yuan Cheng Meng-Meng Ge xiao-jun li Yi-Jing Wang Xi’an Research Institute of High-Tech Xi’anShaanxi710025China Nanyang Technological University Singapore639798Singapore

Recommendation algorithms regard user-item interaction as a sequence to capture the user’s short-term preferences,but conventional algorithms cannot capture information of constantly-changing user interest in complex *** these years,combining the knowledge graphwith sequential recommendation has gained *** advantages of knowledge graph-based recommendation systems are that more semantic associations can improve the accuracy of recommendations,rich association facts can increase the diversity of recommendations,and complex relational paths can hence the interpretability of *** the information in the knowledge graph,such as entities and relations,often fails to be fully utilized and high-order connectivity is unattainable in graph modelling in knowledge graph-based sequential recommender *** address the above problems,a knowledge graph-based sequential recommendation algorithm that combines the gated recurrent unit and the graph neural network(KGSRGG)is proposed in the present ***,entity disambiguation in the knowledge graph is performed on the preprocessing layer;on the embedding layer,the TransR embedding technique is employed to process the user information,item information and the entities and relations in the knowledge graph;on the aggregation layer,the information is aggregated by graph convolutional neural networks and residual connections;and at last,on the sequence layer,a bi-directional gated recurrent unit(Bi-GRU)is utilized to model the user’s sequential *** research results showed that this newalgorithm performed better than existing sequential recommendation algorithms on the MovieLens-1M and Book-Crossing datasets,as measured by five evaluation indicators.

关键词： Sequential recommendation knowledge graph graph neural network gated recurrent unit

Characteristics of secondary electron emission from few layer graphene on silicon(111) surface

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Chinese Physics B 2022年第10期31卷 549-562页

作者： Guo-Bao Feng Yun li xiao-jun li Gui-Bai Xie Lu liu National Key Laboratory of Science and Technology on Space Microwave China Academy of Space TechnologyXi’an 710100China School of Computer Science and Engineering Xi’an University of TechnologyXi’an 710048China

As a typical two-dimensional(2D) coating material, graphene has been utilized to effectively reduce secondary electron emission from the surface. Nevertheless, the microscopic mechanism and the dominant factor of secondary electron emission suppression remain controversial. Since traditional models rely on the data of experimental bulk properties which are scarcely appropriate to the 2D coating situation, this paper presents the first-principles-based numerical calculations of the electron interaction and emission process for monolayer and multilayer graphene on silicon(111) substrate. By using the anisotropic energy loss for the coating graphene, the electron transport process can be described more realistically. The real physical electron interactions, including the elastic scattering of electron-nucleus, inelastic scattering of the electron-extranuclear electron, and electron-phonon effect, are considered and calculated by using the Monte Carlo method. The energy level transition theory-based first-principles method and the full Penn algorithm are used to calculate the energy loss function during the inelastic scattering. Variations of the energy loss function and interface electron density differences for 1 to 4 layer graphene coating Go Si are calculated, and their inner electron distributions and secondary electron emissions are analyzed. Simulation results demonstrate that the dominant factor of the inhibiting of secondary electron yield(SEY) of Go Si is to induce the deeper electrons in the internal scattering process. In contrast, a low surface potential barrier due to the positive deviation of electron density difference at monolayer Go Si interface in turn weakens the suppression of secondary electron emission of the graphene layer. Only when the graphene layer number is 3, does the contribution of surface work function to the secondary electron emission suppression appear to be slightly positive.

关键词： secondary electron emission graphene on silicon numerical simulation

Effect of Polynomial Expressed Distribution Dust Particles for Unmagnetized Two-Ion-Temperature Dusty Plasma

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Communications in Theoretical Physics 2009年第8期52卷 346-350页

作者： HE Guang-jun li xiao-li liN Mai-Mai SHI Yu-Ren DUAN Wen-Shan Department of Physics Northwest Normal University Lanzhou 730070 China

linear dispersion relation for linear wave and a Kadomtsev-Petviashvili (KP) equation for nonlinearwave are given for the unmagnetized two-ion-temperature cold dusty plasma with many different dust grain *** numerical results of variations of linear dispersion with respect to the different dust size distribution are ***,how the amplitude,width,and propagation velocity of solitary wave vary vs different dust size distribution isalso studied numerically in this paper.

关键词： polynomial expressed dust size distribution linear dispersion relation Kadomtsev-Petviashvili (KP) equation

Design, Synthesis and Biological Activity of Substituted-N-[4-(substituted-phenylsulfamoyl)phenyl]benzamide as Potential AHAS Inhibitors

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Chinese Chemical Letters 2006年第12期17卷 1555-1558页

作者： Jian Guo WANC Yong jun xiao Yong Hong li Xing Hai liU Zheng Ming li State-Key Laboratory of Elemento-Organic Chemistry Nankai University Tianjin 300071

Based on the crystal structure of AHAS/sulfonylurea complex, we obtained 296 compounds with low binding energy towards AHAS via virtual screening. One series of them have been synthesized. Preliminary bioassay indicated that some compounds displayed good herbicidal activity on rape and bamygrass and inhibited AHAS to some extent. This study indicated the rationality of our molecular design based on the crystal structure of target enzyme.

关键词： AHAS molecular docking organic synthesis biological activity

Design and Realization of a New Type of Constant Current Source with Small Current and High Precision 36

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Design and Realization of a New Type of Constant Current Sou...

Rupture directivity effect on strong ground motion during the 12 May 2008 M_(W)7.9 Wenchuan earthquake

第36届中国控制会议

作者： jun xiao li Xue mei Wang Zhe Xu Xi’an High Tech Research Institute

ISBN: (纸本)9781538629185

Using constant current source as the excitation signal is an effective method for system testing of the *** present,the constant current source circuit built by TL431 voltage regulator does not meet the system test requirements of the aircraft under the condition of small current *** when the temperature span is large,the working circuit does not have the ability to inhibit the temperature drift,of which the temperature drift is *** this paper,the constant current source circuit built by TL431 voltage regulator is *** OP77 and π-type filter circuit to ensure the output accuracy,the design of the resistor network can achieve complementary temperature *** drift is reduced by adjusting the appropriate compensation ***,the superior performance of the improved constant current source is verified by simulation and experiment.

关键词： Small current High precision Low temperature drift Constant current source

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Earthquake Science 2021年第3期34卷 234-245页

作者： Zhao An jun-Ju Xie Yong Zhang xiao-jun li Zeng-Ping Wen Institute of Geophysics China Earthquake AdministrationBeijing 100081China School of Earth and Space Sciences Peking UniversityBeijing 100871China China Earthquake Hazard and Insurance Research Laboratory Beijing 100081China College of Architecture and Civil Engineering Beijing University of TechnologyBeijing 100124China

We focus here on the rupture directivity effect on the spatial distribution and attenuation characteristics of near-field ground motions during the 2008 MW7.9 Wenchuan *** examine the difference between the observed ground motions in and opposite the rupture directions and compare them with Next Generation Attenuation-West2(NGA-West2)ground motion prediction *** isochrone directivity predictor is used to quantify the band-limited nature of the rupture directivity effect on strong ground *** results show that the observed peak ground velocity(PGV)and spectral accelerations of periods of 1.0 s and longer are significantly amplified in the rupture direction,but de-amplified in the opposite direction affected by rupture directivity effect of this *** contrast,the effect of rupture directivity on the observed peak ground acceleration(PGA)and periods of shorter than 1.0 s are relatively *** rupture directivity of this event shows clear period dependent and band limited characteristics with the strongest effect occurring around the period of 7.5 s.

关键词： Wenchuan earthquake long-period ground motion near-fault ground motion rupture directivity