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Contrast-enhanced Ultrasound in Detecting Endoleaks with Failed Computed Tomography Angiography Diagnosis after Endovascular Abdominal Aortic Aneurysm Repair

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Chinese Medical Journal 2015年第18期128卷 2491-2497页

作者： Xiao Yang Yue-Xin Chen Bo Zhang Yu-Xin Jiang Chang-Wei Liu rui-na zhao Qiong Wu Da-Ming Zhang Department of Ultrasound Peking Union Medical College Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100730 China Department of Vascular Surgery Peking Union Medical College Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100730 China Department of Radiology Peking Union Medical College Hospital ChineseAcademy of Medical Sciences and Peking Union Medical College Beijing 100730 China

Background： Endovascular aneurysnl repair （EVAR） is one of the first-line therapies of abdominal aortic aneurysms. Postoperative endoleak is the most common complication of EVAR. Computed tomography angiography （CTA）, which is routine for follow-up, has side effects （e.g., radiation） and also has a certain percentage of missed diagnosis. Preliminary studies on contrast-enhanced ultrasound （CEUS） have shown that the sensitivity of CEUS for detecting endoleak is no lower than that of CTA. To investigate the advantages of CEUS, we conducted CEUS examinations of post-EVAR cases in which CTA failed to detect endoleak or could not verify the type of endoleak. Methods： Post-EVAR patients, who were clinically considered to have endoleak and met the inclusion criteria were enrolled between March 2013 and November 2014. All of the patients underwent color Doppler flow imaging （CDFI） and a CEUS examination. Size, location, microbubble dispersion, and hemodynamic characteristics of leaks were recorded. Comparison between the diagnosis of CEUS and CDF1 was conducted using Fisher＇s exact test and clinical outcomes of all patients were followed up. Results： Sixteen patients were enrolled, and 12 （75%） had endoleaks with verified types by CEUS. Among 12 cases of endoleaks were positive by CEUS, 10 were CDFl-positive, and the four CEUS-negative cases were all negative by CDFI. The diagnostic values of CEUS and CDFI were statistically difl＇erent （P = 0,008）. Six patients with high-pressure endoleaks received endovascular re-intervention guided by CEUS results. One patient with type Ⅲ endoleak had open surgery when endovascular repair failed. Conclusions： C EUS is a new, safe, and effective means for detection ofendoleaks post-EVAR. This technique can be used as a supplement for routine CTA follow-up to provide more detailed information on endoleak and its category.

关键词： Abdominal Aortic Aneurysnl: Color Doppler Flow Imaging Contrast-enhanced Ultrasound: Endoleak EndovascularAneurysm Repair

＂Onion Skin-liked Sign＂ in Thyroid Ultrasonography： A Characteristic Feature of Benign Thyroid Nodules

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Chinese Medical Journal 2016年第13期129卷 1533-1537页

作者： Shen-Ling Zhu Yu-Xin Jiang Xiao Yang Qiong Wu rui-na zhao Jian-Chu Li Ru-Yu Liu Bo Zhang Department of Ultrasound Peking Union Medical College Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Translational Medicine Center of Peking Union Medical College Hospital Beijing 100730 China

Background： Some ultrasonographic （US） signs overlap between benign and malignant nodules. The purpose of this study was to raise a special US sign of benign thyroid nodules, termed the ＂onion skin-liked sign.＂ Methods： Twenty-seven patients with 27 nodules who shrank naturally and the ＂onion skin-liked sign＂ appeared on the final US images were enrolled in the study. The ultrasound characters and risk stratifications at the start and end of observation were compared. Then, thirty goiters with fibrosis and thirty papillary thyroid carcinomas （PTC） were randomly selected from the database of our hospital, matched the sizes of 27 nodules at the end point of observation. The differences of ＂onion skin-liked sign＂ between the two groups were analyzed. Results： The average duration of follow-up of 27 nodules was 24.0 ± 12.2 months （range, 12-65 months）. At the end of the follow-up, the size of the nodules decreased on average by 1.26 ± 0.82 cm （range, 0.3-3.4 cm） and calcification was found in 21 nodules, compared with only 2 nodules with calcification at the start of the follow-up. In addition, only negligible or no blood flow signal could be detected at the periphery of all the nodules and 100% （27/27） were high suspicion at the end of observation. In matched groups, all PTC showed high suspicion of malignancy, 18/30 （60%） goiters with fibrosis were high suspicion and 11/30 （37%） were intermediate suspicion. Twenty-two patients in the group of nodular fibrosis presented ＂onion skin-liked sign,＂ which was not shown in any patient of PTC group. The sensitivity, specificity, positive predictive value, and negative predictive value of ＂onion skin-liked sign＂ in predicting nodular goiter with fibrosis were 73.3%, 100%, 100%, and 78.9%, respectively. Conclusions： The ＂onion skin-liked sign＂ was a characteristic US feature of benign thyroid nodules detected in the follow-up of thyroid nodules. It is useful to differentiate PTCs and nodular goiters with fibrosis.

关键词： Diagnosis Nodular Goiters Papillary Carcinoma Thyroid Ultrasound

Properties of collective flow and pion production in intermediate-energy heavy-ion collisions with a relativistic quantum molecular dynamics model

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Nuclear Science and Techniques 2024年第1期35卷 155-169页

作者： Si-na Wei zhao-Qing Feng School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510640China

The relativistic mean-field approach was implemented in the Lanzhou quantum molecular dynamics transport model(***). Using the ***, the properties of collective flow and pion production were investigated systematically for nuclear reactions with various isospin asymmetries. The directed and elliptic flows of the *** are able to describe the experimental data of STAR Collaboration. The directed flow difference between free neutrons and protons was associated with the stiffness of the symmetry energy, that is, a softer symmetry energy led to a larger flow difference. For various collision energies, the ratio between the π^(-) and π^(+) yields increased with a decrease in the slope parameter of the symmetry energy. When the collision energy was 270 MeV/nucleon, the single ratio of the pion transverse momentum spectra also increased with decreasing slope parameter of the symmetry energy in both nearly symmetric and neutron-rich ***, it is difficult to constrain the stiffness of the symmetry energy with the double ratio because of the lack of threshold energy correction on the pion production.

关键词： Heavy-ion collision Collective flow Pion production Symmetry energy Relativistic mean field

Modified constitutive models for Inconel 718 considering current density and temperature in electrically assisted forming process

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Chinese Journal of Aeronautics 2024年第2期37卷 524-540页

作者： Xuan CUI rui zhao Min WAN School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Jiangxi Research Institute of Beihang University Jiangxi 330000China

Electrically Assisted Forming(EAF)technology has obvious advantages in material *** develop an effective constitutive model considering electrical effects,room temperature and electrically assisted quasi-static uniaxial tensile tests were conducted using ultrathin nickelbased superalloy plates with a thickness of 0.25 *** research focused on the two most widely recognized effects:the Joule thermal and the electric athermal *** mechanism of current action can be divided into two scenarios:one considering the Joule thermal effect only,and the other considering both effects *** basic constitutive models,namely the Modified-Hollomon model and the Johnson-Cook(J-C)model,were selected to be optimized through the classification of two different situations,and four optimized constitutive models were *** was found that the J-C model with simultaneous consideration of the Joule thermal effect and electric athermal effect had the best prediction effect by comparing the results of these four ***,the accuracy of the optimization model was verified by finite element simulation of the electrically assisted stretching optimization *** results show that the constitutive model can effectively predict the temperature effect caused by the Joule heat effect and the athermal effect of current on the material.

关键词： Joule heating Elastoplasticity Plastic deformation Superalloys Constitutive models

Plasma-exfoliated g-C_(3)N_(4) with oxygen doping: tailoring photocatalytic properties

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Frontiers of Chemical Science and Engineering 2024年第2期18卷 27-39页

作者： Yuxin Li Junxin Guo rui Han zhao Wang national Engineering Research Centre of Industry Crystallization Technology School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China

Heteroatom doping and defect engineering have been proposed as effective ways to modulate the energy band structure and improve the photocatalytic activity of g-C_(3)N_(4). In this work, ultrathin defective g-C_(3)N_(4) was successfully prepared using cold plasma. Plasma exfoliation reduces the thickness of g-C_(3)N_(4) from 10 nm to 3 nm, while simultaneously introducing a large number of nitrogen defects and oxygen atoms into g-C_(3)N_(4). The amount of doped O was regulated by varying the time and power of the plasma treatment. Due to N vacancies, O atoms formed strong bonds with C atoms, resulting in O doping in g-C_(3)N_(4). The mechanism of plasma treatment involves oxygen etching and gas expansion. Photocatalytic experiments demonstrated that appropriate amount of O doping improved the photocatalytic degradation of rhodamine B compared with pure g-C_(3)N_(4). The introduction of O optimized the energy band structure and photoelectric properties of g-C_(3)N_(4). Active species trapping experiments revealed ·O_(2)^(–) as the main active species during the degradation.

关键词： graphitic carbon nitride cold plasma oxygen doping nitrogen defect visible-light photocatalysis

Microstructure evolution and mechanical properties of brazing joint for ultra-thin-walled Inconel 718 considering grain size effect and brazing temperature

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Chinese Journal of Aeronautics 2024年第2期37卷 541-556页

作者： rui zhao Yueshuai SONG Hui KANG Min WAN School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Jiangxi Research Institute of Beihang University Jiangxi 330000China

The systematic investigation of the mechanical properties and microstructure evolution process of ultra-thin-walled Inconel 718 capillary brazing joints is of great significance because of the exceptionally high demands on its *** achieve this objective,this study investigates the impact of three distinct brazing temperatures and five typical grain sizes on the brazed joints’mechanical properties and microstructure evolution *** evolution analysis was conducted based on Electron Back Scatter Diffraction(EBSD),Scanning Electron Microscopy(SEM),X-Ray Diffraction(XRD),High-Resolution Transmission Electron Microscopy(HRTEM),and Focused Ion Beam(FIB).Besides,the mechanical properties and fracture behavior were studied based on the uniaxial tension tests and in-situ tension *** findings reveal that the brazing joint’s strength is higher for the fine-grain capillary than the coarse-grain one,primarily due to the formation of a dense branch structure composed of G-phase in the brazing *** effects of grain size,such as pinning and splitting,are amplified at higher brazing ***,micro-cracks initiate around brittle intermetallic compounds and propagate through the eutectic zone,leading to a cleavage fracture *** fracture stress of fine-grain specimens is higher than that of coarse-grain due to the complex micro-crack ***,this study contributes significantly to the literature by highlighting the crucial impact of grain size on the brazing properties of ultra-thin-walled Inconel 718 structures.

关键词： EYWORDS Ultra-thin-walled structure Brazing Inconel 718 Grain size effect Brazing temperature

Broadband intelligent programmable metasurface with polarization-modulated self-adaptive electromagnetic functionality switching

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Photonics Research 2024年第7期12卷 1395-1409页

作者： XIMING LI rui XU XIAOFENG SUN YUAN zhao zhao YANG GUOHONG DU College of Electronic Engineering Chengdu University of Information TechnologyChengdu 610225China

Programmable metasurfaces have received a great deal of attention due to their ability to dynamically manipulate electromagnetic(EM) waves. Despite the rapid growth, most of the existing metasurfaces require manual control to switch among different functionalities, which poses severe limitations on practical applications. Here, we put forth an intelligent metasurface that has self-adaptive EM functionality switching in broadband without human participation. It is equipped with polarization discrimination antennas(PDAs) and feedback components to automatically adjust functionalities for the different incident polarization information.

关键词： equipped adjust polarization

The Multi-parameter Test of Gravitational Wave Dispersion with Principal Component Analysis

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Research in Astronomy and Astrophysics 2024年第5期24卷 140-150页

作者： Zhi-Chu Ma rui Niu Wen zhao CAS Key Laboratory for Research in Galaxies and Cosmology Department of AstronomyUniversity of Science and Technology of ChinaHefei 230026China School of Astronomy and Space Sciences University of Science and Technology of ChinaHefei 230026China

In this work, we consider a conventional test of gravitational wave(GW) propagation which is based on the phenomenological parameterized dispersion relation to describe potential departures from General Relativity(GR)along the propagation of GWs. But different from tests conventionally performed previously, we vary multiple deformation coefficients simultaneously and employ the principal component analysis(PCA) method to remedy the strong degeneracy among deformation coefficients and obtain informative posteriors. The dominant PCA components can be better measured and constrained, and thus are expected to be more sensitive to potential departures from the waveform model. Using this method we analyze ten selected events and get the result that the combined posteriors of the dominant PCA parameters are consistent with GR within 99.7% credible intervals. The standard deviation of the first dominant PCA parameter is three times smaller than that of the original dispersion parameter of the leading order. However, the multi-parameter test with PCA is more sensitive to not only potential deviations from GR but also systematic errors of waveform models. The difference in results obtained by using different waveform templates hints that the demands of waveform accuracy are higher to perform the multiparameter test with PCA. Whereas, it cannot be strictly proven that the deviation is indeed and only induced by systematic errors. It requires more thorough research in the future to exclude other possible reasons in parameter estimation and data processing.

关键词： gravitational waves-gravitation-black hole physics

Effects of desert plant communities on soil enzyme activities and soil organic carbon in the proluvial fan in the eastern foothills of the Helan Mountain in Ningxia,China

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Journal of Arid Land 2024年第5期16卷 725-737页

作者： SHEN Aihong SHI Yun MI Wenbao YUE Shaoli SHE Jie ZHANG Fenghong GUO rui HE Hongyuan WU Tao LI Hongxia zhao na College of Forestry and Prataculture of Ningxia University Yinchuan 750021China School of Geography and Planning of Ningxia University Yinchuan 750021China Ningxia Hui Autonomous Region Agricultural Comprehensive Development Center Yinchuan 750002China Ningxia Helan Mountain national nature Reserve Administration Yinchuan 750021China Yinchuan Yinxi Ecological Protection Forest Management Center Yinchuan 750002China

It is of great significance to study the effects of desert plants on soil enzyme activities and soil organic carbon(SOC)for maintaining the stability of the desert *** this study,we studied the responses of soil enzyme activities and SOC fractions(particulate organic carbon(POC)and mineral-associated organic carbon(MAOC))to five typical desert plant communities(Convolvulus tragacanthoides,Ephedra rhytidosperma,Stipa breviflora,Stipa tianschanica ***,and Salsola laricifolia communities)in the proluvial fan in the eastern foothills of the Helan Mountain in Ningxia Hui Autonomous Region,*** recorded the plant community information mainly including the plant coverage and herb and shrub species,and obtained the aboveground biomass and plant species diversity through sample surveys in late July *** samples were also collected at depths of 0–10 cm(topsoil)and 10–20 cm(subsoil)to determine the soil physicochemical properties and enzyme *** results showed that the plant coverage and aboveground biomass of *** community were significantly higher than those of ***,***,and *** *** communities(P<0.05).Soil enzyme activities varied among different plant *** the topsoil,the enzyme activities of alkaline phosphatase(ALP)andβ-1,4-glucosidas(βG)were significantly higher in *** and *** *** communities than in other plant communities(P<0.05).The topsoil had higher POC and MAOC contents than the ***,the content of POC in the topsoil was 18.17%–42.73%higher than that in the *** structural equation model(SEM)indicated that plant species diversity,soil pH,and soil water content(SWC)were the main factors influencing POC and *** soil pH inhibited the formation of POC and promoted the formation of ***,SWC stimulated POC production and hindered MAOC *** study aimed to gain insight into the effects of desert plant c

关键词： proluvial fan desert plant community soil enzyme activity particulate organic carbon mineral-associated organic carbon Helan Mountain