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BL03HB: a Laue microdiffraction beamline for both protein crystallography and materials science at SSRF

Nuclear Science and Techniques 2024年第7期35卷 68-78页

作者： Zhi-Jun Wang Si-Sheng Wang zheng-Huang su Li Yu Yu-Zhu Wang Bo sun wen wen Xing-Yu Gao Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai201210China University of Chinese Academy of Science Beijing100049China

A Laue microdiffraction beamline (BL03HB) was constructed at the Shanghai SynchrotronRadiation Facility (SSRF). This beamline featu res two consecutive focusing points in twodifferent sectors within its end station, the first dedicated to protein crystallography and theother tailored to materials science applications. Based on a superbend dipole magnet with amagnetic field of 2.29 T, a two-stage focusing design was implemented with two sets of Kirkpatrick- Baez mirrors to achieve a micro white beam as small as 4.2 um X4.3 pμm at the firstsector and 09 pum X 1.3 pum at the second sector in the standard beamline operation mode at *** X-ray microbeam in the two sectors can be easily switched between monochromatic andwhite beams by moving a four-bounce monochromator in or out of the light path, respectively. Inthe protein crystallography sector, white-beam Laue microdifraction was dermonstrated tosuccessully determine the structure of protein crystals from only a few images of diffraction data .collected by a Pilatus 2 M area detector. In the materials science sector, the white -beam Lauediffraction was collected in a reflection geometry using another Pilatus 2 M area detector, whichcould map the microstructural distribution on the sample surface by scanning the samples. Ingeneral, the BL03HB beamline promotes the application of Laue microdiffraction in both proteincrystallgraphy and materials science. This paper presents a comprehensive overview of theBL03HB beamline, end station, and the first commission results.

关键词： Crystallography White-beam Laue microdiffraction Beamline Synchrotron

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P-and SV-wave dispersion and attenuation in saturated microcracked porous rock with aligned penny-shaped fractures

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Petroleum Science 2024年第1期21卷 143-161页

作者： Sheng-Qing Li wen-Hao Wang Yuan-Da su Jun-Xin Guo Xiao-Ming Tang School of Geosciences China University of Petroleum(East China)Qingdao 266580ShandongChina Laoshan National Laboratory Qingdao 266071ShangdongChina Guangdong Provincial Key Laboratory of Geophysical High-resolution Imaging Technology Southern University of Science and TechnologyShenzhen 518055GuangdongChina Department of Earth and Space Sciences Southern University of Science and TechnologyShenzhen 518055GuangdongChina

P-and SV-wave dispersion and attenuation have been extensively investigated in saturated poroelastic media with aligned ***,there are few existing models that incorporate the multiple wave attenuation mechanisms from the microscopic scale to the macroscopic ***,in this work,we developed a unified model to incorporate the wave attenuation mechanisms at different scales,which includes the microscopic squirt flow between the microcracks and pores,the mesoscopic wave-induced fluid flow between fractures and background(FB-WIFF),and the macroscopic Biot's global flow and elastic scattering(ES)from the *** Tang's modified Biot's theory and the mixed-boundary conditions,we derived the exact frequency-dependent solutions of the scattering problem for a single penny-shaped fracture with oblique incident P-and *** then developed theoretical models for a set of aligned fractures and randomly oriented fractures using the Foldy *** results indicated that microcrack squirt flow considerably influences the dispersion and attenuation of P-and SV-wave *** coupling effects of microcrack squirt flow with the FB-WIFF and ES of fractures cause much higher velocity dispersion and attenuation for P waves than for SV *** oriented fractures substantially reduce the attenuation caused by the FB-WIFF and ES,particularly for the ES attenuation of SV *** a comparison with existing models in the limiting cases and previous experimental measurements,we validated our model.

关键词： Aligned fractures P-and SV-wave Dispersion and attenuation Microcracked porous background FB-WIFF Elastic scattering Squirt flow

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Enhancement of comprehensive properties of Nb–Si based in-situ composites by Ho rare earth doping

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Rare Metals 2024年第9期43卷 4508-4520页

作者： Wei Wei Qi Wang Rui-Run Chen Chao-wen zheng Yan-Qing su National Key Laboratory for Precision Hot Processing of Metals School of Materials Science and EngineeringHarbin Institute of Technology

This study examines the microstructure,mechanical properties （with a focus on room-temperature toughness）, and oxidation resistance of Ho-doped NbDSi based in-situ composites. The base alloy consists of the coarse primary Nb5Si3phase and the Nb5Si3+Nbss （Nb solid solution） eutectic cells. Ho doping influences the solidification path. When the Ho doping is higher than0.2 at%, the alloys transform into eutectic alloys. Ho can be solid-solved in trace amounts in the Nbss phase. However, most of Ho forms a stable Ho oxide phase, which alleviates oxygen contamination problem to some ***, the interface separation between Ho oxide and other phases reduces the plastic deformation ***, with 0.4 at%Ho doping, the KQvalue is18.03 MPa·m1/2, which is 31.1%higher than that of the base alloy. The strength of the Ho-doped alloys does not deteriorate with an increase in toughness. However, the large network-like Ho2O3in the 0.8Ho alloy causes a decrease in toughness and strength. In addition, the Ho oxide phase effectively blocks the inward oxygen *** 0.8 at%Ho doping, the oxidation mass gain per unit area is 10.16 mg·cm2, which is 39.7%lower than that of the base alloy.

关键词： Ho Microstructure Nb–Si based composites Properties Rare earth elements

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Protein crystallization with DNA templates

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Particuology 2024年第3期86卷 262-268页

作者： Bo Zhang Jia Yu zhe Pu wenhui Guo Ruoqi Yang Yu wen Zhijiang Rong Hui Wang Xiaoli Wu Bo Wang Hongyan sun School of Environment and Resources Taiyuan University of Science and TechnologyTaiyuan030024China School of Chemical Engineering and Technology Taiyuan University of Science and TechnologyTaiyuan030024China

Protein crystallization plays a significant role in three-dimensional structural analysis and protein *** is important to increase the crystallization efficiency,which is possible by adding hetero-geneous templates in crystallization *** is biologically compatible and artificially designable polymer,which is easy to *** this study,single-and double-stranded DNA of precise sequences were designed and used as templates to promote protein crystallization of lysozyme and ***-fluence of DNA,single-stranded DNA with 10,20,40 bases and double-stranded DNA with 10,20,40 base pairs,were *** success rate of obtaining crystals of lysozyme and catalase in equal period was significantly improved with the addition of DNA comparing without templates ***-stranded DNA led to higher nucleation rate than that with single-stranded *** promotion of nucleation was more obvious at low concentration of protein solution and with longer chain DNA *** number and crystallization rate was enhanced with addition of long double-stranded DNA *** the results confirm that DNA is an effective polymer additive to enhance protein crystallization,especially for the application of the scarce protein crystallization.

关键词： DNA Polymer Additive Protein Crystallization

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Vibration-Based Fault Diagnosis for Railway Point Machines Using VMD and Multiscale Fluctuation-Based Dispersion Entropy

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Chinese Journal of Electronics 2024年第3期33卷 803-813页

作者： Yongkui suN Yuan CAO Peng LI Guo XIE Tao wen Shuai su National Engineering Research Center of Rail Transportation Operation and Control System Beijing Jiaotong University School of Electronic and Information Engineering Beijing Jiaotong University Shaanxi Key Laboratory of Complex System Control and Intelligent Information Processing Xi'an University of Technology Frontiers Science Center for Smart High-speed Railway System Beijing Jiaotong University

As one of the most important railway signaling equipment,railway point machines undertake the major task of ensuring train operation *** fault diagnosis for railway point machines becomes a hot *** the advantage of the anti-interference characteristics of vibration signals,this paper proposes an novel intelligent fault diagnosis method for railway point machines based on vibration signals.A feature extraction method combining variational mode decomposition(VMD) and multiscale fluctuation-based dispersion entropy is developed,which is verified a more effective tool for feature ***,a two-stage feature selection method based on Fisher discrimination and ReliefF is proposed,which is validated more powerful than single feature selection ***,support vector machine is utilized for fault *** comparisons show that the proposed method performs *** diagnosis accuracies of normal-reverse and reverse-normal switching processes reach 100% and 96.57% ***,it is a try to use new means for fault diagnosis on railway point machines,which can also provide references for similar fields.

关键词： Fault diagnosis Vibrations support vector machines Diversity reception Switches Feature extraction Rail transportation

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基于轮廓关键点形状上下文描述的BIM模型版本对比方法

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图学学报 2023年第5期44卷 1034-1040页

作者：刘建秀苏文哲苏治东中国电建集团中南勘测设计研究院有限公司湖南长沙410140 湖南省BIM工程技术研究中心湖南长沙410140

在工程全生命周期过程中,需求、参与方、工况等因素的变化使得BIM模型变更频繁,模型校审工作量巨大,校审的基础是识别不同版本之间模型的差异。针对模型中的结构化信息,可采用文本比较的方式。对于非结构化的几何信息,提出了基于轮廓关... 详细信息

在工程全生命周期过程中,需求、参与方、工况等因素的变化使得BIM模型变更频繁,模型校审工作量巨大,校审的基础是识别不同版本之间模型的差异。针对模型中的结构化信息,可采用文本比较的方式。对于非结构化的几何信息,提出了基于轮廓关键点和表面描述点进行形状上下文描述的方法。该方法首先通过计算获得模型的轮廓线,其次采用轮廓线均匀采样和表面泊松盘均匀采样的方式获取关于模型的特征描述,最后对模型统计特征进行定量比较。相较于目前主流的随机采样方法,该方法不仅能通过较少的采样点获得对模型的稳定描述,提高对比效率,且对模型结构改变十分敏感,同时也可以抵抗因曲面细分或简化带来的影响。本文方法在某水电工程的部分非标准化构件中进行实验验证,在模型差异化对比方面取得了良好的效果。

关键词：模型版本对比轮廓线关键点均匀采样

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Utility of real-time 3D visualization system in the early stage of phacoemulsification training

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International Journal of Ophthalmology(English edition) 2024年第3期17卷 577-582页

作者： zhe Xu Dan Chen Jing-Wei Xu Yi-Xuan Feng Ce Shi Li Zhang wen Xu Eye Center the Second Affiliated HospitalSchool of MedicineZhejiang UniversityHangzhou 310009Zhejiang ProvinceChina zhejiang Provincial Key Laboratory of Ophthalmology Hangzhou 310009Zhejiang ProvinceChina zhejiang Provincial Clinical Research Center for Eye Diseases Hangzhou 310009Zhejiang ProvinceChina zhejiang Provincial Engineering Institute on Eye Diseases Hangzhou 310009Zhejiang ProvinceChina

●AIM:To determine the teaching effects of a real-time three dimensional(3D)visualization system in the operating room for early-stage phacoemulsification training.●METHODS:A total of 10 ophthalmology residents of the first-year postgraduate were *** the residents were novices to cataract ***-time cataract surgical observations were performed using a custom-built 3D visualization *** training lasted 4wk(32h)in all.A modified International Council of Ophthalmology’s Ophthalmology surgical Competency Assessment Rubric(ICO-OSCAR)containing 4 specific steps of cataract surgery was *** self-assessment(self)and expert-assessment(expert)were performed through the microsurgical attempts in the wet lab for each participant.●REsuLTS:Compared with pre-training assessments(self 3.2±0.8,expert 2.5±0.6),the overall mean scores of posttraining(self 5.2±0.4,expert 4.7±0.6)were significantly improved after real-time observation training of 3D visualization system(Psurgical items were significantly improved both self and expert assessment after training(Psurgical *** is a useful tool to improve teaching efficiency of surgical education.

关键词： 3D visualization system phacoemulsification training wet lab

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Serrated flow behavior of GH536 superalloy under different loading rates at room temperature

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Rare Metals 2024年第5期43卷 2317-2323页

作者： wen-Xiang Gao Dong Ma Li-Li Zhao Fan Ye Ling Shao su-Jun Wu School of Materials Science and Technology Beihang UniversityBeijing100091China

Serrated flow phenomenon has been widely observed among different metals due to the potential influence on their *** tensile tests of nickel-based superalloy GH536 were carried out at loading rates of 0.06,0.60,3.60,and 36.00 mm·min^(-1)at room temperature,*** tensile stress-strain curves demonstrate repetitive and discontinuous yielding behavior,namely serrated *** is observed that the stress-strain curves were dominated by type B serration,and original annealing twin boundaries(TBs)were distorted to various degrees under comparatively different lower tensile *** contrast,the TBs almost disappear,and the type B serrations become smoother and regular under the higher loading *** phenomenon can be attributed to the interactions between TBs and dislocations during tensile *** effects of the mobile and immobile dislocations illustrate the unsteady amplitude of serrations observed in stress-strain *** electron microscope images of tested pieces reveal the interaction of dislocation and TB,with dislocation tangling around the TBs.

关键词： Nickel-based superalloy Serrations Twin boundaries Deformation mechanism

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Mesenteric adipose tissue B lymphocytes promote intestinal injury in severe acute pancreatitis by mediating enteric pyroptosis

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Hepatobiliary & Pancreatic Diseases International 2024年第3期23卷 300-309页

作者： Qing Huang Jia-wen Liu Hai-Bin Dong zheng-Jie Wei Jin-zhe Liu Yu-Tang Ren Xuan Jiang Bo Jiang Department of Gastroenterology Beijing Tsinghua Changgung HospitalSchool of Clinical MedicineTsinghua UniversityBeijing 102218China

Background:Visceral adipose tissue(VAT)has been linked to the severe acute pancreatitis(SAP)prognosis,although the underlying mechanism remains *** has been reported that pyroptosis worsens *** present study aimed to verify whether mesenteric adipose tissue(MAT,a component of VAT)can cause secondary intestinal injury through the pyroptotic ***:Thirty-six male Sprague Dawley(SD)rats were divided into six different *** rats were randomly divided into the SAP and control *** monitored the changes of MAT and B lymphocytes infiltration in MAT of SAP *** SAP rats were injected with MAT B lymphocytes or phosphate buffer solution(PBS).The remaining twelve SAP rats were first injected with MAT B lymphocytes,and then with MCC950(NLRP3 inhibitor)or *** collected blood and tissue samples from pancreas,gut and MAT for ***:Compared to the control rats,the SAP group showed inflammation in MAT,including higher expression of tumor necrosis factor(TNF-α)and interleukin-6(IL-6),lower expression of IL-10,and histological *** cytometry analysis revealed B lymphocytes infiltration in MAT but not T lymphocytes and *** SAP rats also exhibited intestinal injury,characterized by lower expression of zonula occludens-1(ZO-1)and occludin,higher levels of lipopolysaccharide and diamine oxidase,and pathological *** expression of NLRP3 and n-GSDMD,which are responsible for pyroptosis,was increased in the intestine of SAP *** injection of MAT B lymphocytes into SAP rats exacerbated the inflammation in *** upregulation of pyroptosis reduced tight junction in the intestine,which contributed to the SAP progression,including higher inflammatory indicators and worse histological *** administration of MCC950 to SAP+MAT B rats downregulated pyroptosis,which subsequently improved the intestinal barrier and ameliorated inflammatory response of ***:In SAP,MAT B lymphocytes aggravated local

关键词： Acute pancreatitis Mesenteric adipose tissue B lymphocyte Intestinal barrier Pyroptosis

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Clinical practice guidelines for neoadjuvant therapy in patients with early-stage breast cancer:Chinese Society of Breast surgery practice guidelines 2022

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Chinese Medical Journal 2024年第12期137卷 1387-1388页

作者： Juliang Zhang Ting Wang zhe Wang Jing Fan Xiaolong Xu Jing Kong Xinxin wen Rui Ling Yinhua Liu Department of Thyroid Breast and Vascular SurgeryXijing HospitalThe Fourth Military Medical UniversityXi’anShaanxi 710032China Breast Disease Center Peking University First HospitalBeijing 100034China.

Neoadjuvant therapy can yield clinical benefits in earlystage breast cancer with *** indications,treatment regimens,and efficacy of neoadjuvant therapy have been investigated,which have contributed valuable clinical evidence.[1,2]The Chinese Society of Breast surgery convened a panel of breast disease experts to review and discuss the literature on neoadjuvant therapy for breast cancer and evaluate relevant evidence by referring to the Grading of Recommendations,Assessment,Development,and Evaluations(GRADE)*** into account China’s specific circumstances,the society and participating experts developed the Clinical Practice Guidelines for Neoadjuvant Therapy for Early-stage Breast Cancer(Version 2022)to serve as a reference for breast surgeons in China.

关键词： surgery Breast breast

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