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Appendicitis combined with Meckel’s diverticulum obstruction, perforation, and inflammation in children: Three case reports

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World Journal of Clinical Cases 2024年第4期12卷 865-871页

作者： Yi-Meng Sun Wang Xin yu-fang liu Zhe-Ming Guan Hao-Wen Du Ning-Ning Sun Yong-Dong liu School of Clinical Medicine Weifang Medical UniversityWeifang 261000Shandong ProvinceChina Department of Pediatric Surgery Weifang People’s HospitalWeifang 261000Shandong ProvinceChina Department of Burn Surgery Weifang People’s HospitalWeifang 261000Shandong ProvinceChina

BACKGROUND Meckel’s diverticulum is a common congenital malformation of the small intestine,with the three most common complications being obstruction,per-foration,and *** date,only a few cases have been reported *** children,the clinical symptoms are similar to *** most of the imaging features are nonspecific,the preoperative diagnosis is not *** addition,the clinical characteristics are highly similar to pediatric acute appendicitis,thus special attention is necessary to distinguish Meckel’s diver-ticulum from pediatric *** with poor disease control should undergo laparoscopic exploration to avoid serious complications,including intestinal necrosis,intestinal perforation and gastrointestinal *** SUMMARY This report presents three cases of appendicitis in children combined with intestinal obstruction,which was caused by fibrous bands(ligaments)arising from the top part of Meckel's diverticulum,diverticular perforation,and diver-ticular *** three patients,aged 11-12 years,had acute appendicitis as their initial clinical *** were treated by laparoscopic surgery with a favorable outcome.A complete dataset including clinical presentation,dia-gnostic imaging,surgical information,and histopathologic findings was also *** Preoperative diagnosis of Meckel’s diverticulum and its complications is challenging because its clinical signs and complications are similar to those of appendicitis in *** combined with laparotomy is useful for diagnosis and treatment.

关键词： Meckel’s diverticulum Complications Intestinal obstruction Perforation Appendicitis in children Mesodiverticular band Ligament Diverticular disease Case report

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Ab initio Study on Ionization Energies of 1-Methyl-hypoxanthine

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Chinese Journal of Chemical Physics 2012年第5期25卷 540-544,I0003页

作者： Ke-dong Wang Da-peng Yang yu-fang liu College of Physics and information Engineering Henan Normal UniversityXinxianE 453007China College of Mathematics and Information Science North China University of Water Resources andElectric PowerZhengzhou 450011China

Six low-lying tautomers of 1-methyl-hypoxanthine have been studied at the B3LYP/aug-cc- pVDZ level. Two tautomers NTH and N9H with the comparable energies are far more stable than the others. The vertical ionization energies of the tautomers calculated with ab initio electron propagator theory in the P3/aug-cc-pVDZ approximation are in agreement with the experimental data from photoelectron spectroscopy. According to the calculated relative energies and the comparison between the simulated and the experimental photoelectron spectra, it demonstrates that there are at least two tautomers of 1-methyl-hypoxanthine in the gas-phase experiments.

关键词： Tautomer Ionization energy Relative energy Photoelectron spectrum

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TDDFT Study on Excited-State Hydrogen Bonding of 2'-Deoxyguanosine in H2O Solution

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Chinese Journal of Chemical Physics 2015年第6期28卷 -页

作者： Dong-lin Li Hui Li Yong-gang Yang yu-fang liu Department of Physics Henan Normal University Xinxiang 453007 China

The mono and dihydrated complexes of 2′-deoxyguanosine have been used to elucidate the importance of the 2′-hydroxy group in the hydration. Density functional theory and time-dependent density functional theory methods were performed to investigate the ground-and excited-state hydrogen bonding properties of 2′-deoxyguanosine-water (2′-dG-W) and 2′-deoxyguanosine-2water (2′-dG-2W). Infrared spectra, geometric optimizations, frontier molecular orbitals and Mulliken charges have also been studied. The results demonstrated that the excited-state intramolecular hydrogen bonding dynamics of complexes 2′-dG-W and 2′-dG-2W behaves differently upon photoexcitation, while their intermolecular hydrogen bonding dynamics behaves similarly. Moreover, the significant weakening of the intermolecular hydrogen bond O4⋯H1–N1 and the formation of the new strong hydrogen bond O4⋯H3–N2 in the 2′-dG-2W upon photoexcitation were due to the geometric structure bending of guanine and the rigidity of related molecules. In addition, the charge transfer properties were theoretically investigated by analysis of molecular orbital.

关键词： Hydrate Time-dependent density functional theory Rigidity Hydrogen bonding dynamics

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Compressive behavior of hybrid steel-polyvinyl alcohol fiber-reinforced concrete containing fly ash and slag powder:experiments and an artificial neural network model

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2021年第9期22卷 721-735页

作者： fang-yu liu Wen-qi DING Ya-fei QIAO Lin-bing WANG Qi-yang CHEN Department of Civil and Environmental Engineering Virginia Polytechnic Institute and State UniversityVirginia 24061USA Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghai 200092China Key Laboratory of Geotechnical and Underground Engineering Ministry of EducationShanghai 200092China Department of Civil and Environmental Engineering University of Illinois at Urbana-ChampaignUrbana 61801USA

Understanding the mechanical behavior of hybrid fiber-reinforced concrete(HFRC),a composite material,is crucial for the design of HFRC and HFRC *** this study,a series of compression experiments were performed on hybrid steelpolyvinyl alcohol(PVA)fiber-reinforced concrete containing fly ash and slag powder,with a focus on the fiber content/ratio effect on its compressive behavior;a new approach was built to model the compression behavior of HFRC by using an artificial neural network(ANN)*** proposed ANN model incorporated two new developments:the prediction of the compressive stress-strain curve and consideration of 23 features of components of *** build a database for the ANN model,relevant published data were also *** indices were used to train and evaluate the ANN *** highlight the performance of the ANN model,it was compared with a traditional equation-based *** results revealed that the relative errors of the predicted compressive strength and strain corresponding to compressive strength of the ANN model were close to 0,while the corresponding values from the equation-based model were ***,the ANN model is better able to consider the effect of different components on the compressive behavior of HFRC in terms of compressive strength,the strain corresponding to compressive strength,and the compressive stress-strain *** an ANN model could also be a good tool to predict the mechanical behavior of other composite materials.

关键词： Experiments Artificial neural network(ANN) Hybrid fiber-reinforced concrete(HFRC) Compressive behavior Stress-strain curve

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Impact of climate change on food security in the Central Asian countries

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Science China Earth Sciences 2024年第1期67卷 268-280页

作者： fang SU yu liu Lvfan CHEN Rustam OROZBAEV Liangcheng TAN School of Economics and Management Northwest UniversityXi’an 710127China School of Economics and Management Shaanxi University of Science and TechnologyXi’an 710021China State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’an 710061China Institute of Geology National Academy of Sciences of Kyrgyz RepublicBishkek 720040Kyrgyzstan Institute of Global Environmental Change Xi’an Jiaotong UniversityXi’an 710049China

The current and potential impacts of global warming have generated widespread concerns about food security among all sectors of *** Asian countries located deep in the interior of Asia with fragile ecological environments and lower agricultural technology are particularly more prone to severe threats from climate *** on panel data acquired in five Central Asian countries from 1990 to 2019,a C-D-C model was developed to study how climate change affects food security in the region and to predict future *** study found that the level of food security has generally increased for these five Central Asian countries over the past 30 years,with Kazakhstan and Tajikistan having the highest and lowest food security levels,*** average annual temperature and precipitation exhibit an inverted U-shaped relationship with the region’s food security,with the most positive effect on the food security of *** high and low temperatures have significantly affected food security in the studied region,with Turkmenistan experiencing the most significant negative *** number of frost days had no significant effect on food *** analysis of future climate showed that the temperature and precipitation in Central Asia will continue to increase from 2030 to 2090,which will negatively impact the food security of these *** is recommended that the Central Asian countries enhance their understanding of climate risks,strengthen scientific climate research,and develop multiple adaptation strategies in ***,they are encouraged to consolidate international cooperation,reducing greenhouse gas emissions effectively and maintaining the ability to ensure food security.

关键词： Global warming Extreme climate Food security Future forecasts Five Central Asian countries

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Single dose of ibutilide for conversion of persistent atrial fibrillation after radiofrequency ablation

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Chinese Medical Journal 2011年第5期124卷 710-713页

作者： HOU yu fang Pi-hua liu Jun LI Xiao-feng HU Ji-qiang ZHANG Shu Clinical EP Lab and Arrhythmia Center Fuwai Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100037 China

Background Patients with persistent or permanent atrial fibrillation （AF） often need direct current cardioversion after radiofrequency ablation. The aim of this study was to investigate the effectiveness and safety of ibutilide for cardioversion of persistent or permanent atrial fibrillation after radiofrequency ablation and the factors related to conversion. Methods Patients with persistent or permanent atrial fibrillation were treated with combined ablation strategy including circumferential pulmonary vein isolation, linear ablation and CAFE potential ablation. If AF was not terminated after ablation, ibutilide was used for cardioversion （1 mg, intravenous injection in 10 minutes）. These patients were divided into a conversion group and a non-conversion group according to whether AF was converted to sinus rhythm within 30 minutes after administration. ECG monitoring was performed during the injection of ibutilide. Atrial waves recorded by coronary sinus electrodes were measured for calculating average wavelength of AF waves in six seconds. The QT interval was measured immediately after conversion and 2 hours after injection of *** Forty patients whose AF was not converted to sinus rhythm after radiofrequency ablation were given an intravenous injection of ibutilide. Of the 40 patients, 29 cases were converted to sinus rhythm, with a conversion rate of 72.5%. The average conversion time was （13.2±5.5） minutes. Compared with the conversion group, patients in the non-conversion group had a longer history of AF （9.4±5.3） years vs. （4.3±2.8） years, P 〈0.05）, and a markedly enlarged left atrium （47.3±2.9） mm vs. （42.1±4.5） mm, P〈0.05）. There were no significant differences in gender, age, body mass index and left ventricular function between the two groups. Ibutilide significantly prolonged the average wavelength of the AF wave （171.8±29.5） ms vs. （242.0±40.0） ms, P 〈0.001）. Two hours after ibutilide treatment, the QT interval was significantly shortened （

关键词： ibutilide conversion atrial fibrillation radiofrequency ablation

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Control of Virtual Synchronous Generator for Frequency Regulation Using a Coordinated Self-adaptive Method

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 175-184页

作者： Hongwei fang Zhiwei yu School of Electrical and Information Engineering and Key Laboratory of Tianjin Electric Power System Simulation and Control Tianjin UniversityTianjin 300072China

Power inverter adopting virtual synchronous generator(VSG)control can provide inertia support for distributed generation ***,it cannot take into account the dynamic regulation characteristics of ***,when the system encounters a sudden change in load or disturbance,the dynamic process of frequency regulation will be greatly *** view of this issue,an improved VSG control strategy based on a coordinated self-adaptive(CSA)method is *** time domain analysis method is used to study the influences of virtual inertia and damping parameter perturbation on the system steady and dynamic ***,in order to make the control strategy suitable for large load changes and suppress frequency variations beyond the limit,the secondary frequency modulation is introduced into the control *** the coordinated adaptive control of virtual inertia,virtual damping and frequency modulation,the dynamic performance of vSG frequency regulation can be obviously *** and experiment results have verified the effectiveness of the proposed CSA control strategy.

关键词： Coordinated self-adaptive method frequency regulation time domain analysis virtual synchronous generator

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Sequence-Controlled Synthesis of Alternating Poly(ester amide)s using Water as Control Agent in One-Pot

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Chinese Journal of Polymer Science 2024年第8期42卷 1015-1020页

作者： Tao liu fang-fang Niu Kan Cheng yu-Min Xia Bo-Mou Ma Xue-Li Wang Jian-Yong yu Yong He State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai 201620China Innovation Center for Textile Science and Technology Donghua UniversityShanghai 201620China

Poly(ester amide)s(PEAs)attract much attention as a new kind of biodegradable ***,the synthesis of PEAs with sequence-regulated chain structures is still complicated due to the multistep polymerization,high monomer purity,as well as the usage of organic solvents,which greatly inhibits its development and ***,a one-pot strategy without solvent was developed to synthesize the alternating PEA fromα,ω-amino alcohol and dicarboxylic acid by sequential polycondensation,where water was used as the controlling agent for amidation and ***,the amidation and esterification were controlled to proceed in turn by adding or removing water,realizing the one-pot preparation of alternating *** resultant PEA is characterized by^1H-and^(13)C-NMR,and its chain structure is confirmed to be highly quasi-alternating similar to alternating PEAs prepared by classical methods The evaluations from DSC and DMA demonstrate that the properties of quasi-alternating PEA(T_(m)=102℃,ΔH_(m)=30J·g^(-1))are far superior to those of random PEA(T_(m)=72℃,ΔH_(m)<1 J·g^(-1)).

关键词： Biodegradable macromolecules Polymer architectures Sequence-controlled synthesis One-pot polymerization

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SGT-Net: A Transformer-Based Stratified Graph Convolutional Network for 3D Point Cloud Semantic Segmentation

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Computers, Materials & Continua 2024年第6期79卷 4471-4489页

作者： Suyi liu Jianning Chi Chengdong Wu fang Xu Xiaosheng yu Faculty of Robot Science and Engineering Northeastern UniversityShenyang110167China State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang110016China Institutes for Robotics and Intelligent Manufacturing Chinese Academy of SciencesShenyang110169China SIASUN Robot&Automation Co. Ltd.Shenyang110169China

In recent years,semantic segmentation on 3D point cloud data has attracted much *** 2D images where pixels distribute regularly in the image domain,3D point clouds in non-Euclidean space are irregular and inherently ***,it is very difficult to extract long-range contexts and effectively aggregate local features for semantic segmentation in 3D point cloud *** current methods either focus on local feature aggregation or long-range context dependency,but fail to directly establish a global-local feature extractor to complete the point cloud semantic segmentation *** this paper,we propose a Transformer-based stratified graph convolutional network(SGT-Net),which enlarges the effective receptive field and builds direct long-range ***,we first propose a novel dense-sparse sampling strategy that provides dense local vertices and sparse long-distance vertices for subsequent graph convolutional network(GCN).Secondly,we propose a multi-key self-attention mechanism based on the Transformer to further weight augmentation for crucial neighboring relationships and enlarge the effective receptive *** addition,to further improve the efficiency of the network,we propose a similarity measurement module to determine whether the neighborhood near the center point is *** demonstrate the validity and superiority of our method on the S3DIS and ShapeNet *** ablation experiments and segmentation visualization,we verify that the SGT model can improve the performance of the point cloud semantic segmentation.

关键词： 3D point cloud semantic segmentation long-range contexts global-local feature graph convolutional network dense-sparse sampling strategy

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Cosmetics use-related adverse events

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Chinese Medical Journal 2019年第17期132卷 2135-2136页

作者： Su-Lian Yang yue Zheng yun-Qing Zhang Cong-Xiu Ye Jin-Ling Yi yu-fang liu Wei Lai Department of Dermatology and Venereology The Third Affiliated Hospital Sun Yat-sen University Guangzhou Guangdong 510630 China

To the Editor: Cosmetics (non-prescription skin care products) use-induced adverse events could present as skin erythema, papules, pruritus, dryness, desquamation, and abnormal discoloration. Non-medicated cosmetics use is more and more common in the China, but little is known about the characteristics of cosmetic-related adverse events.

关键词： pruritus desquamation erythema

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