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Magnetic resonance imaging for local complications of acute pancreatitis: A pictorial review

World Journal of Gastroenterology 2010年第22期16卷 2735-2742页

作者： Xiao, bo zhang, Xiao-Ming Tang, Wei Zeng, nan-Lin Zhai, Zhao-Hua N Sichuan Med Coll Affiliated Hosp Dept Radiol Sichuan Key Lab Med Imaging Nanchong 637000 Sichuan Prov Peoples R China

Acute pancreatitis is a common disease characterized by sudden upper abdominal pain and vomiting. Alcoholism and choledocholithiasis are the most common factors for this disease. The choice of treatment for acute pancreatitis might be affected by local complications, such as local hemorrhage in or around the pancreas, and peripancreatic infection or pseudoaneurysm. Diagnostic imaging modalities for acute pancreatitis have a significant role in confirming the diagnosis of the disease, helping detect the extent of pancreatic necrosis, and for diagnosing local complications. Magnetic resonance imaging (MRI) might be indicated in acute pancreatitis for detecting and characterizing local complications of acute pancreatitis that involve necrotic, hemorrhagic, infectious, vascular, and pseudocyst disorders. The general MRI sequences for pancreatitis require the combined use of T1-weighted, T2-weighted sequences, and magnetic resonance chol-angiopancreatography. For imaging of pancreatic necrosis, the combination of T1-weighted and T2-weighted findings with dynamic contrast-enhanced imaging gives a comprehensive evaluation of the extent of necrosis and full range of inflammatory extension. For imaging of infectious complications, dynamic contrast-enhanced examinations might help differentiate pancreatic cellulitis or abscesses, from pancreatic fluid collection or simple pseudocysts. For vascular abnormalities, the combination of cross-sectional pancreatic parenchyma imaging with MRA represents a single diagnostic modality for the full evaluation of peripancreatic artery and vein involvement, such as arterial pseudoaneurysms and venous thromboses. The purpose of this pictorial review is to examine the MRI appearances of various local complications of acute pancreatitis and to discuss the practical setup of MRI in local complications of acute pancreatitis.

关键词： Pancreas Pancreatitis Complication Magnetic resonance imaging Pictorial review

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Environmentally Friendly Sizing Strategy for Pbo Fiber-reinforced Composites through Building Carbon nanosphere Coatings

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Chinese Journal of Polymer Science 2023年第2期41卷 306-314页

作者： Rong Ling Shao-Hua Wu Chun-Cheng Li Yao-nan Xiao Jia-Jian Liu bo zhang Beijing National Laboratory for Molecular Sciences Key Laboratory of Engineering PlasticsInstitute of ChemistryChinese Academy of Sciences(ICCAS)Beijing100190China University of the Chinese Academy of Sciences Beijing100049China

Sizing treatment has shown great potential in improving the interfacial properties of poly(p-phenylene benzodioxazole)(Pbo)fiber-reinforced composites,but is severely limited due to the use of flammable and explosive organic ***,a new high-efficiency waterborne sizing agent has been developed by using functionalized carbon nanospheres(CNSs)as a *** to abundant oxygen-containing groups,the CNSs greatly improves the surface activity,wettability,and roughness of the Pbo *** a result,the interfacial shear strength of the CNSs sized fiber-reinforced composite increases by 79.6%compared with that of the pristine fiber-reinforced ***,the excellent mechanical and thermal properties of the Pbo fibers remain almost unchanged after sizing ***,this work provides an environmentally friendly and scalable method for constructing a strong interface between the Pbo fibers and the matrix resins,which makes sense in promoting the application of Pbo fiber-reinforced composites in aerospace and military industries.

关键词： Carbon nanospheres Sizing treatment Pbo fiber-reinforced composites Environmentally friendly Scalable methods

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Stem cell therapy:light in the tunnel for penetrating Crohn’s disease

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Gastroenterology Report 2023年第1期11卷 78-87页

作者： nan Lan Xianrui Wu bo Shen Center for Inflammatory bowel Disease Columbia University Irving Medical Center/NewYork Presbyterian HospitalNew YorkNYUSA Department of Colorectal Surgery The 6th Hospital of Sun Yat-Sen UniversityGuangzhouGuangdongP.R.China

Patients with Crohn’s disease frequently suffer from fistula resulting from adverse sequelae of persistent complicated active disease or surgical *** affects a patient’s quality of life and is directly associated with the need for surgical *** of fistula can be made through CT enterography,MR enterography,gastrograffin-based imaging,and transanal *** for fistula mainly consists of medication,endoscopic procedures,and *** are emerging approaches under current investigation,such as stem cell *** results showed a decent response in patients with perianal and rectovaginal fistula with minimal side *** investigation is still needed for other internal fistula.

关键词： Crohn’s disease fistula perianal disease stem cells therapy

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Photometric redshift estimation of galaxies with Convolutional Neural Network

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Research in Astronomy and Astrophysics 2020年第6期20卷 193-202页

作者： Yong-Huan Mu bo Qiu Jian-nan zhang Jun-Cheng Ma Xiao-Dong Fan School of Electronics and Information Engineering Hebei University of TechnologyTianjin 300401China CAS Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China

The abundant photometric data collected from multiple large-scale sky surveys give important opportunities for photometric redshift ***,low accuracy is still a serious issue in the current photometric redshift estimation *** this paper,we propose a novel two-stage approach by integration of Self Organizing Map(SOM)and Convolutional Neural Network(CNN)methods *** SOM-CNN method is tested on the dataset of 150000 galaxies from Sloan Digital Sky Survey Data Release 13(SDSS-DR13).Inthe first stage,we apply the SOM algorithm to photometric data clustering and divide the samples into early-type and *** the second stage,the SOM-CNN model is established to estimate the photometric redshifts of ***,the precision rate and recall rate curves(PRC)are given to evaluate the models of SOM-CNN and Back Propagation(BP).It can been seen from the PRC that the SOM-CNN model is better than BP,and the area of SOM-CNN is 0.94,while the BP is ***,we provide two key error indicators:mean square error(MSE)and *** results show that the MSE of early-type is 0.0014 while late-type is 0.0019,which are better than the BP algorithm 22.2%and 26%,*** compared with Outliers,our result is optimally 1.32%,while the K-nearest neighbor(KNN)algorithm has 3.93%.In addition,we also provide the error visualization figures aboutΔZ andδ.According to the statistical calculations,the early-type with an error of less than 0.1 accounts for 98.86%,while the late-type is 99.03%.This result is better than those reported in the literature.

关键词： galaxies distances and redshifts-techniques photometric-method data analysis

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A FRAMEWORK FOR REAL-VALUED CIPHER SYSTEMS

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Journal of Systems Science & Complexity 2007年第4期20卷 486-491页

作者： Zhaozhi zhang nan JIANG Institute of Systems Science Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 China College of Computer Science and Technology Beijing University of Technology Beijing 100022 China

Most cipher systems designed thus far are binary-valued or integer-valued cipher systems. Their security relies on the assumption that one-way functions exist. Though the existence of one-way functions has not been proved yet, most cryptographic researchers believe that one-way functions exist. In addition, many candidates for one-way functions have been proposed. Therefore, the key step for developing real-valued cipher systems is to define real one-way functions and to propose candidates for them. In this paper, based on computational complexity theory over the real field, we give two definitions of real one-way functions; one is for digital one-way functions and the other is for general one-way functions. Candidates for these two classes of one-way functions are also proposed. Moreover, we present two examples to demonstrate that the candidates for both digital one-way functions and general one-way functions can be applied to construct secure real-valued cipher systems.

关键词： Computational complexity theory digital one-way function general one-way function real-valued cipher system.

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Multidimensional Waveform Design for MIMO SAR Interferometry

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Chinese Journal of Electronics 2018年第1期27卷 198-205页

作者： LIU nan zhang Linrang National Key Laboratory of Radar Signal Processing Xidian University

One key of Multiple-input multiple-output(MIMO) Synthetic aperture radar(SAR) interferometry is the effective separation of the echoes originating from different transmissions. A multidimensional waveform design method for MIMO SAR interferometry is presented. By exploiting the wavenumber shift and Doppler-band shift phenomenon in the design of transmitted signals, the echo separation can be efficiently accomplished via the filtering operations in range-frequency domain and azimuth-spatial domain. Such waveform design can meet the requirement of MIMO SAR imaging on integrated cross interference level without reduce the swath width. Such waveform design also improves the coherence between the independent observations and enlarges the unambiguity range of height estimation. The results of the numerical simulations demonstrate the feasibility of the proposed waveform design method.

关键词： Synthetic aperture radar(SAR) interferometry Multiple-input multiple-output(MIMO) Multidimensional waveform design Echo separation

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Microstructure,phase composition and wear resistance of low valence electron concentration Al_(x)CoCrFeNiSi high-entropy alloys prepared by vacuum arc melting

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Journal of Iron and Steel Research International 2021年第2期28卷 181-189页

作者： Bing-qian Jin nan-nan zhang Yue zhang De-yuan Li Department of Material Science and Engineering Shenyang University of TechnologyShenyang 110870LiaoningChina Provincial Key Laboratory of Advanced Welding Technology and Automation Shenyang 110870LiaoningChina

The low valence electron concentration(VEC)Al_(x)CoCrFeNiSi(x=0.5,1.0,1.5 and 2.0)high-entropy alloys(HEAs)were designed by the fundamental properties of the constituent elements and prepared by vacuum arc melting *** effects of Al addition on the crystal structure and microstructure were *** microhardness and wear property were also *** results showed that the microstructure transformed from dendritic crystal to equiaxed *** was found that FCC phase gradually decreased with the increasing Al content and disappeared until in a composition of 1.0 in Al_(x)CoCrFeNiSi *** FCC phase was found with continuously adding Al,while the phase fraction of BCC increased from 85.0% to 91.8%,and VEC decreased from 7.00 to *** microhardness was increased gradually from 598 up to 909 HV with addition of Al from 0.5 to *** was the same of the compressive strength results,which improved from 1200 to 1920 *** wear coefficient and mass loss were in line with mechanical properties evolution,which was attributed to the microstructure transformation into equiaxed crystal and the increase in BCC phase.

关键词： High-entropy alloy Valence electron concentration Microstructure Phase assemblage Wear resistance

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Organ transplantation management in the midst of the COVID-19 outbreak: a synopsis

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Hepatobiliary Surgery and Nutrition 2020年第2期9卷 250-252页

作者： bo-Han zhang Lyu-nan Yan Jia-Yin Yang Department of Liver Surgery and Liver Transplantation Center Organ Transplantation CenterWest China Hospital of Sichuan UniversityChengdu 610041China

On December 8,2019,the first case of unexplained pneumonia was reported in China,in Wuhan,Hubei Province(1).By March 6,2020,over 100,000 confirmed cases of coronavirus disease 2019(COVID-19),and more than 3,400 deaths have been reported worldwide(data from National Health Commission of the People’s Republic of China,Official Channels of Hong Kong,Macao and Taiwan,and World Health Organization).COVID-19,which is caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),is bound to have widespread ramifications on the clinical management system,organ transplantation being a prime *** on the transplant waitlist are generally in poor ***,post-transplant patients with weak immunity stemming from the long-term and regular administration of immunosuppressants are more likely to contract the SARS-CoV-2 infection than are healthy ***,when considering transplant patient safety,balancing organ allocation principles with epidemic prevention and control is a dilemma for transplant teams.

关键词： prevention Taiwan likely

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单元整体教学视角下高中英语课程思政实践研究

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英语教师 2025年第1期 151-156页

作者：邵晨张博广东省中山市第一中学广东中山528400

概述英语课程思政的内涵和特征。从逻辑关系、育人路线、场域和抓手三个角度分析通过单元整体教学落实高中英语课程思政的可行性。以人教版(2019年)高中《英语》必修三Unit 2 Morals and Virtues为例,探索单元整体教学视角下高中英语课... 详细信息

概述英语课程思政的内涵和特征。从逻辑关系、育人路线、场域和抓手三个角度分析通过单元整体教学落实高中英语课程思政的可行性。以人教版(2019年)高中《英语》必修三Unit 2 Morals and Virtues为例,探索单元整体教学视角下高中英语课程思政实践路径,即梳理单元大小观念,挖掘思政元素;设计单元学习目标,融入思政理念;规划单元学习活动,聚焦思政价值;优化单元教学评价,增强思政实效。

关键词：高中英语课程思政单元整体教学大观念

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Effect of vanadium addition on microstructure and properties of AI_(0.5)Cr_(0.9)FeNi_(2.5)multi-principal alloys

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Journal of Iron and Steel Research International 2021年第5期28卷 586-596页

作者： De-xi Hao nan-nan zhang Yue zhang De-yuan Li Department of Material Science and Engineering Shenyang University of TechnologyShenyang 110870LiaoningChina Provincial Key Laboratory of Advanced Welding Technology and Automation Shenyang 110870LiaoningChina

AI_(0.5)Cr_(0.9)FeNi_(2.5)V_(x)(x=0,0.2,0.4,0.6,0.8,1.0)multi-principal alloys were prepared by vacuum arc *** effect of vanadium addition on its microstructure and properties was *** results show that the alloys of all components exhibited an FCC single-phase *** the addition of vanadium,the microstructure of the alloy changed from dendrites to equiaxed crystals,the grains were remarkably refined,and the layered CrV phase was exhibited,which improved the properties of the *** yield strength of the alloy was slightly improved,and the alloys with various components presented good *** V content reached 0.8,the yield strength was 600 MPa,and no fracture ***-wear testing showed that the wear debris was reduced with the addition of V *** sample with V element content of 0.4 had the best friction and wear *** surface grooves became shallow,the worn debris was less,and the wear mechanism was mainly abrasive *** polarisation curve showed that the alloy with V element content of 0.2 has the best corrosion *** passivation interval reached 900 *** corrosion potential and the corrosion current density were-496.299 mV and 2.759μA/cm^(2),respectively.

关键词： Multi-principal alloy Vacuum arc melting CrV phase Adhesive wear Electrochemical testing

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