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Normalized glandular dose coefficients for digital breast tomosynthesis using detailed Chinese breast models

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Nuclear Science and Techniques 2024年第5期35卷 42-59页

作者： Jia-Hao Wang rui qiu An-Kang hu Ye-qi Liu Zhen Wu hui Zhang Jun-Li Li Department of Engineering Physics Tsinghua UniversityBeijing 100084China Key Laboratory of Particle and Radiation Imaging Ministry of EducationTsinghua UniversityBeijing 100084China Joint Institute of Tsinghua University Nuctech Company Limited BeijingBeijing 100084China

The rise in breast cancer diagnoses among Chinese women has necessitated the use of X-ray breast screening,which carries a radiation *** study aimed to provide a dosimetry protocol for the Chinese female population to replace the traditional standard that utilizes simplified breast models,for the accurate estimation of the mean glandular dose of a patient undergoing digital breast tomosynthesis(DBT).The first set of detailed Chinese female breast models and representative breast parameters was *** backscatter radiation and computational efficiency,we improved the combination of these models and the Chinese reference adult female whole-body voxel *** acquisition for four commercial DBT systems that are widely employed in China was simulated using the Monte Carlo method to obtain the normalized glandular dose coefficients of DBT(D_(gN)^(DBT))and the glandular depth dose(D_(g)^(dep)(z))for different breast characteristics and X-ray *** calculated a series of D_(gN)^(DBT) values for breasts with different percentage mass glandularities(5%,25%,50%,75%,and 100%)and compressed breast thicknesses(2,3,4,5,6,and 7 cm)at various tube potentials(25,28,30,32,35,and 49 kV)and target/filter combinations(W/Rh,W/Al,Mo/Mo,Rh/Rh,and Rh/Ag).The parameter dependence of the breast characteristics and beam conditions on D_(gN)^(DBT) in detailed breast models was *** D_(gN)^(DBT) results were 14.6-51.0%lower than those of the traditional dosimetry standard in *** difference in D_(gN)^(DBT) was mainly due to a decrease in the depth of the main energy deposition area caused by the glandular distribution along the depth *** results obtained in this study may be used to improve breast dosimetry in China and provide more detailed information on risk assessment during DBT.

关键词： Digital breast tomosynthesis Normalized glandular dose coefficients Detailed breast model Monte Carlo simulation

Percutaneous drug-eluting stent implantation in dextrocardia:case report

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Chinese Medical Journal 2007年第3期120卷 248-250页

作者： ZHANG qi ZHANG rui-yan hu Jian SHEN Wei-feng Department of Cardiology Shanghai Ruijin Hospital Medical School of Shanghai Jiaotong Unisersity Shanghai 200025 China

Although situs inversus with dextrocardia is a rare clinical phenomenon, the association with coronary artery disease（CAD） is at the same frequency as in the general popuLation. Few cases of dextrocardia complicated with CAD was reported before. The feasibility and prognosis of percutaneous coronary intervention （PCI） in such case still remains unclear because of the uncommon anatomical abnormality, especially in the drug-eluting stent （DES） era. Here we report a female case with dextrocardia and CAD was successfully treated by DES implantation.

关键词： dextrocardia coronary stent

Acoustic radiation force on a cylindrical composite particle with an elastic thin shell and an internal eccentric liquid column in a plane ultrasonic wave field

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Chinese Physics B 2024年第9期33卷 423-431页

作者： rui-qi Pan Zhi-Wei Du Cheng-hui Wang Jing hu Run-Yang Mo Institute of Shaanxi Key Laboratory of Ultrasonics Shaanxi Normal UniversityXi’an 710119China

A model with three-layer structure is introduced to explore the acoustic radiation force(ARF)on composite particles with an elastic thin *** acoustic scattering of cylinder and the thin-shell theorem,the ARF expression was derived,and the longitudinal and transverse components of the force and axial torque for an eccentric liquid-filled composite particle was *** was found that many factors,such as medium properties,acoustic parameters,eccentricity,and radius ratio of the inner liquid column,affect the acoustic scattering field of the particle,which in turn changes the forces and *** acoustic response varies with the particle structures,so the resonance peaks of the force function and torque shift with the eccentricity and radii ratio of *** acoustic response of the particle is enhanced and exhibits higher force values due to the presence of the elastic thin shell and the coupling effect with the eccentricity of the internal liquid *** decrease of the inner liquid density may suppress the high-order resonance peaks,and internal fluid column has less effects on the change in force on composite particle at ka>3,while limited differences exist at ka<*** axial torque on particles due to geometric asymmetry is closely related to ka and the *** distribution of positive and negative force and torque along the axis ka exhibits that composite particle can be manipulated or separated by *** theoretical analysis can provide support for the acoustic manipulation,sorting,and targeting of inhomogeneous particles.

关键词： acoustic radiation force acoustic scattering of cylinders elastic shell composite particles

The New Methods for Characterization of Molecular Weight of Supramolecular Polymers

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Chinese Journal of Polymer Science 2024年第10期42卷 1403-1413,I0006页

作者： hui Liu rui hu Zi-qing hu Xiao-Fan Ji Key Laboratory of Materials Chemistry for Energy Conversion and Storage Ministry of EducationHubei Key Laboratory of Materials Chemistry and Service FailureHubei Engineering Research Center for Biomaterials and Medical Protective MaterialsSchool of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan430074China

Supramolecular polymers,as a type of dynamic polymers,are subordinate to the interdisciplinary field of polymer chemistry and supramolecular chemistry,whose development has greatly promoted the prosperity of new ***,molecular weight is one of the most important parameters of supramolecular polymers,which affects the physical/chemical properties and processing applications of *** new methods for characterizing the molecular weight of supramolecular polymers is crucial for advancing the development of supramolecular *** this review,we elaborate and summarize three strategies for characterizing the molecular weight of supramolecular polymers that recently reported by our research group according to the characteristics of supramolecular polymers,including(1)the molecular weight distinction corresponding to variable fluorescence colors,(2)matching different molecular weights with different fluorescence lifetime,(3)transforming supramolecular polymers into mechanically interlocked polymers or covalent ***,we also discuss the limitations of current methods for characterizing supramolecular *** hope that this review can promote the development of supramolecular polymers and significantly inspire to exploit new methods to characterizing molecular weight of supramolecular polymers.

关键词： Supramolecular polymers Molecular weight Self-assembly Mechanically interlocked polymers Dynamic polymers

Simplified design of nonlinear damper parameters and seismic responses for long-span cable-stayed bridges with nonlinear viscous dampers

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Frontiers of Structural and Civil Engineering 2024年第7期18卷 1103-1116页

作者： huihui LI Lifeng LI rui hu Meng YE College of Civil and Transportation Engineering Shenzhen UniversityShenzhen 518060China Guangdong Provincial Key Laboratory of Durability for Marine Civil Engineering Shenzhen UniversityShenzhen 518060China College of Civil Engineering Hunan UniversityChangsha 410082China

Viscous dampers are widely used as passive energy dissipation devices for long-span cable-stayed bridges for mitigation of seismic load-induced ***,complicated finite element(FE)modeling,together with repetitive and computationally intensive nonlinear time-history analyses(NTHAs)are generally required in conventional design *** streamline the preliminary design process,this paper developed a simplified longitudinal double degree of freedom model(DDFM)for single and symmetric twin-tower cable-stayed *** on the proposed simplified longitudinal DDFM,the analytical equations for the relevant mass-and stiffness-related parameters and longitudinal natural frequencies of the structure were derived by using analytical and energy *** of the relationship between the nonlinear viscous damper parameters and the equivalent damping ratio was achieved through the equivalent linearization ***,the analytical equations of longitudinal seismic responses for long-span cable-stayed bridges with nonlinear viscous dampers were *** on the developed simplified DDFM and suggested analytical equations,this paper proposed a simplified calculation framework to achieve a simplified design method of nonlinear viscous damper ***,the effectiveness and applicability of the developed simplified longitudinal DDFM and the proposed calculation framework were further validated through numerical analysis of a practical cable-stayed ***,the results indicated the following.1)For the obtained fundamental period and longitudinal stiffness,the differences between results of the simplified longitudinal DDFM and numerical analysis were only 2.05%and 1.5%,respectively.2)Relative calculation errors of the longitudinal girder-end displacement and bending moment of the bottom tower section of the bridge obtained from the simplified longitudinal DDFM were limited to less than 25%.3)The equivalent damping ratio of nonline

关键词： cable-stayed bridges viscous dampers simplified analytical model equivalent damping ratio seismic mitigation

Reconfigurable mechanism-based metamaterials for ternary-coded elastic wave polarizers and programmable refraction control

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Applied Mathematics and Mechanics(English Edition) 2024年第7期45卷 1225-1242页

作者： Zhou hu Zhibo WEI Yan CHEN rui Zhu School of Aerospace Engineering Beijing Institute of TechnologyBeijing100081China School of Mechanical Engineering Tianjin UniversityTianjin300350China Key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education Tianjin UniversityTianjin300350China

Elastic metamaterials with unusual elastic properties offer unprecedented ways to modulate the polarization and propagation of elastic ***,most of them rely on the resonant structural components,and thus are frequency-dependent and ***,we present a reconfigurable 2D mechanism-based metamaterial which possesses transformable and frequency-independent elastic *** on the proposed mechanism-based metamaterial,interesting functionalities,such as ternarycoded elastic wave polarizer and programmable refraction,are ***,unique ternary-coded polarizers,with 1-trit polarization filtering and 2-trit polarization separating of longitudinal and transverse waves,are first ***,the strong anisotropy of the proposed metamaterial is harnessed to realize positive-negative bi-refraction,only-positive refraction,and only-negative ***,the wave functions with detailed microstructures are numerically verified.

关键词： elastic metamaterial elastic wave reconfigurable design zero mode ternary code programmable refraction

A Probabilistic Approach for Predicting Vessel Motion

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IEEE/CAA Journal of Automatica Sinica 2024年第8期11卷 1877-1879页

作者： qi hu Jingyi Liu Zongyu Zuo 7th Research Division Beihang University(BUAA)Beijing 100191China 54th Research Institute of China Electronics Technology Group Corporation Shijiazhuang 050081China

Dear Editor,This letter addresses the challenge of forecasting the motion of real-world vessels over an extended period with a limited amount of available *** employing stochastic differential equation(SDE)modeling,we integrate both deterministic and stochastic components of the available ***,we establish a recursive prediction methodology based on Bayes’rule to update the model state when new measurements are ***,we develop a stochastic model tailored specifically to vessel dynamics and introduce an approximation method to tackle computational ***,we present an application example and conduct a comparative experiment to validate the effectiveness and superiority of the proposed method.

关键词： method stochastic letter

Efficacy comparison of fruquintinib,regorafenib monotherapy or plus programmed death-1 inhibitors for microsatellite stable metastatic colorectal cancer

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World Journal of Gastrointestinal Oncology 2024年第6期16卷 2449-2462页

作者： Tian-qi An hui qiu Quan-Bo Zhou Hong Zong Shuang hu Yu-Gui Lian rui-hua Zhao Department of Oncology The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450000Henan ProvinceChina Department of Hepato-Pancreato-Biliary Surgery Peking University Cancer Hospital and InstituteBeijing 100000China Department of Colorectal Surgery The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450000Henan ProvinceChina

BACKGROUND Regorafenib(R)and fruquintinib(F)are the standard third-line regimens for colorectal cancer(CRC)according to the National Comprehensive Cancer Network guidelines,but both have limited *** phase 2 trials have indicated that R or F combined with immune checkpoint inhibitors can reverse immunosuppression and achieve promising efficacy for microsatellite stable or proficient mismatch repair(MSS/pMMR)*** to the lack of studies comparing the efficacy between F,R,F plus programmed death-1(PD-1)inhibitor,and R plus PD-1 inhibitors(RP),it is still unclear whether the combination therapy is more effective than *** To provide critical evidence for selecting the appropriate drugs for MSS/pMMR metastatic CRC(mCRC)patients in clinical *** A total of 2639 CRC patients were enrolled from January 2018 to September 2022 in our hospital,and 313 MSS/pMMR mCRC patients were finally *** A total of 313 eligible patients were divided into F(n=70),R(n=67),F plus PD-1 inhibitor(FP)(n=95)and RP(n=81)*** key clinical characteristics were well balanced among the *** median progression-free survival(PFS)of the F,R,FP,and RP groups was 3.5 months,3.6 months,4.9 months,and 3.0 months,*** median overall survival(OS)was 14.6 months,15.7 months,16.7 months,and 14.1 *** FP regimen had an improved disease control rate(DCR)(P=0.044)and 6-month PFS(P=0.014)and exhibited a better trend in PFS(P=0.057)compared with F,and it was also significantly better in PFS than RP(P=0.030).RP did not confer a significant survival benefit;instead,the R group had a trend toward greater benefit with OS(P=0.080)compared with *** significant differences were observed between the R and F groups in PFS or OS(P>0.05).CONCLUSION FP is superior to F in achieving 6-month PFS and DCR,while RP is not better than *** has an improved PFS and 6-month PFS compared with RP,but F and R had similar clinical ***,FP may be a

关键词： Colorectal cancer Fruquintinib Regorafenib Programmed death-1 inhibitor Real-world

Removal of pathogenic indicator microorganisms during partial nitrification:the role of free nitrous acid

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Frontiers of Environmental Science & Engineering 2024年第3期18卷 93-102页

作者： Jiaojiao Xu Xiaotian Chen rui Tang Jingwei Feng Shoujun Yuan Wei Wang Zhen-hu hu Anhui Engineering Laboratory of Rural Water Environment and Resource School of Civil EngineeringHefei University of TechnologyHefei 230009China Hefei 168 High School Hefei 230025China Shanghai Key Laboratory of Materials Protection and Advanced Materials in Electric Power Shanghai University of Electric PowerShanghai 200090China

Digested wastewater contains pathogenic microorganisms and high ammonia concentrations,which can pose a potential risk to public *** removal of pathogens and nitrogen is crucial for the post-treatment of digested *** nitrification-anammox is an energy-saving nitrogen removal *** nitrous acid(FNA),an intermediate product of partial nitrification,has the potential to inactivate ***,the efficiency and mechanisms of FNA-related inactivation in pathogens during partial nitrification remains *** this study,Enterococcus and Escherichia coli(***)were selected to investigate the efficiency and mechanisms of FNA-related inactivation in partial nitrification *** results revealed that 83%±13%and 59%±27%of *** and Enterococcus were removed,respectively,in partial nitrification process at FNA concentrations of 0.023−0.028 mg/*** the concentration of FNA increased from 0 to 0.5 mg/L,the inactivation efficiencies of *** and Enterococcus increased from 0 to 99.9%and 89.9%,*** exhibited a higher resistance to FNA attack compared to ***.3D-laser scanning microscopy(3D-LSM)and scanning electron microscopy(SEM)revealed that FNA exposure caused the surface collapse of *** and Enterococcus,as well as visible pore formation on the surface of *** cells.4',6-Diamidino-2-phenylindole dihydrochloride n-hydrate(DAPI)/propidium iodide(PI)and biomolecule leakage confirmed that inactivation of *** and Enterococcus occurred due to breakdown of cell walls and cell *** findings indicate that partial nitrification process can be used for the removal of residual pathogenic microorganisms.

关键词： Partial nitrification Free nitrous acid Pathogenic indicator microorganism Inactivation Cell structure