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Rollback reconstruction for TDC enhanced perfusion imaging

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Nuclear Science and Techniques 2021年第8期32卷 23-33页

作者： Jia-Shun Liu yi-kun zhang Hui Tang Li-Bo zhang Ben-Qiang Yang ying Yan Li-Min Luo Yang Chen Laboratory of Image Science and Technology Southeast UniversityNanjing 210096China Department of Radiology General Hospital of the Northern Theater of the Chinese People’s Liberation ArmyShenyang 110016China Department of Radiotherapy General Hospital of the Northern Theater of the Chinese People’s Liberation ArmyShenyang 110016China Centre de Recherche en Information Biomedicale SinoFrancais(LIA CRIBs) 35000 RennesFrance

Tomographic perfusion imaging is a significant imaging modality for stroke ***,the low rotational speed of the C-arm(6–8 s per circle)is a challenge for applying perfusion imaging in C-arm cone beam computed tomography(CBCT).Traditional reconstruction methods cannot remove the artifacts caused by the slow rotational speed or acquire enough sample points to restore the time density curve(TDC).This paper presents a dynamic rollback reconstruction method for *** proposed method can improve the temporal resolution by increasing the sample points used for calculating the *** with existing techniques,the algorithm allows slow-rotating scanners to be used for perfusion imaging *** the experiments,the proposed method was compared with other dynamic reconstruction algorithms based on standard reconstruction and the temporal interpolation *** presented algorithm could improve the temporal resolution without increasing the X-ray exposure time or contrast agent.

关键词： Rollback reconstruction CBCT Time resolution Time density curve

Flux phases in the extended Hubbard model on the triangular lattice

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Science China(Physics,Mechanics & Astronomy) 2024年第9期67卷 148-153页

作者： Yuge Chen kun Jiang yi zhang Jiangping Hu Beijing National Laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100190China Department of Physics and Institute for Quantum Science and Technology Shanghai UniversityShanghai 200444China Shanghai Key Laboratory of High Temperature Superconductors and International Center of Quantum and Molecular Structures Shanghai UniversityShanghai 200444China Kavli Institute of Theoretical Sciences University of Chinese Academy of SciencesBeijing 100190China New Cornerstone Science Laboratory Beijing 100190China

Using the unrestricted Hartree-Fock variational method,we study the extended Hubbard model in the triangular lattice at 3/4 *** to the nesting instability of the Fermi surface,various density wave states compatible with the 2×2 supercell are found as the ground state by tuning the onsite and nearest neighbor repulsions U and ***,the flux phases with complex bond order parameters are realized in a wide range of the U-V phase *** also acquire nontrivial topological properties due to the spontaneous breaking of the time-reversal *** study suggests that the flux phases can be stabilized by the interplay between short-range repulsive interactions in correlated electron systems.

关键词： flux state triangular lattice Hubbard model

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Effect of Ti_(p) Content on the Work Hardening and Softening Behavior of Mg-Zn-Ca Alloy

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Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 551-560页

作者： Jin-Kai zhang Cui-Ju Wang yi-Dan Fan Chao Xu Kai-Bo Nie kun-kun Deng Shanxi Key Laboratory of Advanced Magnesium-Based Materials College of Materials Science and EngineeringTaiyuan University of TechnologyTaiyuan 030024China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China

The Ti_(p)/ZX60 composites with different Ti_(p) contents were prepared by semi-solid stirring *** extrusion,the microstructure,work hardening and softening behavior of the Ti_(p)/ZX60 composites were analyzed compared with the ZX60(Mg-6Zn-0.2Ca)*** results showed that the addition of Ti_(p) could not only promote the nucleation of dynamic recrystallized(DRXed)grains,but also be propitious to the refinement of DRXed *** increasing Ti_(p) content,the size of DRXed grains decreased accompanied with increasing volume fraction of DRXed *** the Ti_(p) content increased to 15 vol.%,the average size and volume fraction of DRXed grains reached to~0.32μm and 93.2%,***,both the strength and elongation were improved by the addition of Ti_(p).With increasing content of Ti_(p),a substantial increase in the strength was achieved with little change in the ***,the elongation decreased sharply when the Ti_(p) content further increased to 15 vol.%.The addition of Ti_(p) led to an increase in the work hardening rate,which gradually increased with increasing Ti_(p) ***,the softening rate did not demonstrate the same tendency with increasing Ti_(p) *** the conventional ceramic particles,the Ti_(p) can be deformed in coordination with the matrix alloy,which imparted a higher softening rate to the matrix *** though the softening rate improved as the Ti_(p) content increased from 5 to 10 vol.%,it dropped deeply as the Ti_(p) content increased to 15 vol.%owing to the fracture of Ti_(p) during extrusion.

关键词： Titanium particle content Particle reinforced magnesium matrix composites Work hardening Softening behavior Mechanical properties

Combination of Nitrogen-Rich Skeleton and Coordination Group:Synthesis of a High-Energy Primary Explosive Based on 1H-Tetrazole-5-Carbohydrazide

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Defence Technology（防务技术） 2024年第1期31卷 271-277页

作者： Tingwei Wang Zujia Lu Shu Bu Baolong Kuang Lu zhang Zhenxin yi kun Wang Shunguan Zhu Jianguo zhang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China School of Chemical Engineering Nanjing University of Science and Technology200 Xiaolingwei StreetXuanwuNanjing 210094China Department of Chemistry Laboratory of Structure and Functional Regulation of Hybrid MaterialsAnhui UniversityMinistry of EducationHefei 230601China

The high energy coordination compounds Cu(TZCA)_(2)(ClO_(4))_(2)(ECCs-1) was prepared by 1H-tetrazole-5-carbohydrazide(TZCA) with a high energy skeleton and a strong coordination ability *** the same time,the reaction activity of the ligand was explored,and the single crystal structure of it and intermediate were *** structures of all substances were characterized by IR and *** the structure and composition of ECCs-1 are confirmed by ESP,AC,SEM and *** and chemical properties tests show that ECCs-1 has an acceptable thermal stability(T_(d)=177℃) and extremely sensitive mechanical stimulation(IS=1 J,FS=5 N).The comprehensive performance test results show that ECCs-1 has excellent initiation *** addition,the decomposition mechanism of ECCs-1 is explored from two aspects of experiment and theoretical calculation.

关键词： 1H-tetrazole-5-carbohydrazide Primary explosive Decomposition mechanism Coordination polymers Laser

Understand the Temperature Sensing Behavior of Solid-state Polymerized PEDOT Hybrid Based on X-ray Scattering Studies

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Chinese Journal of Polymer Science 2024年第1期42卷 105-112,I0010页

作者： Zhen-Hang He Guang-Feng Liu Ze-kun Zhou Zhen Liu yi-Shu Zeng Peng zhang School of Materials Science and Engineering Key Laboratory for Polymeric Composite and Functional Materials of Ministry of EducationSun Yat-sen UniversityGuangzhou 510275China Shanghai Advanced Research Institute(zhangjiang Laboratory) Chinese Academy of SciencesShanghai 201204China

Poly(3,4-ethylenedioxythiophene)(PEDOT) is one of the most successful conductive polymers that recently has been used in wearable sensors for human health monitoring. In this work, we prepared a series of PEDOT hybrids consisting of PEDOT, sodium poly(styrene sulfonate)(PSSNa) and polyethylene oxide(PEO), and their preparation could be scaled-up via an adapted solid-state polymerization process. The resistance of the as-prepared PEDOT:PSS/PEO hybrid shows clear temperature response, i.e., it decreases almost linearly with the temperature increase. To understand this phenomenon, the in situ synchrotron radiation wide-and small-angle X-ray scattering(WAXS/SAXS) characterizations were undertaken to study the temperature-dependent microstructure change of the PEDOT:PSS/PEO hybrid. It demonstrated that PEDOT formed conductive paths in the hybrids, which were not destroyed by the PEO crystallization. As temperature increased, the PEO crystals' melting and the accompanying reorganization of PEDOT chains endowed the hybrid sample temperature responsiveness. Based on these fundamental knowledges, the hybrid materials were used to fabricate flexible wearable sensor that showing temperature sensing performance with an accuracy of 1 ℃. These findings shed lights on the scalable manufacturing of wearable sensors for body temperature monitoring.

关键词： Solid-state polymerization PEDOT hybrid Structure-property correlation X-ray scattering

Could the EU carbon border adjustment mechanism promote climate mitigation?An economy-wide analysis

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Advances in Climate Change Research 2024年第3期15卷 557-571页

作者： kun zhang Yun-Fei YAO Xiang-Yan QIAN Yu-Fei zhang Qiao-Mei LIANG yi-Ming WEI College of Economics and Management Beijing University of TechnologyBeijing 100124China Center for Energy and Environmental Policy Research Beijing Institute of TechnologyBeijing 100081China School of Management and Economics Beijing Institute of TechnologyBeijing 100081China Beijing Key Laboratory of Energy Economics and Environmental Management Beijing 100081China Sinopec Research Institute of Petroleum Engineering SinopecBeijing 100101China College of Economics and Management Nanjing Agricultural UniversityNanjing 210095China

Due to concerns about carbon leakage and sectoral competitiveness,the European Union(EU)proposed implementing the carbon border adjustment mechanism(CBAM).The effectiveness and potential negative consequences of CBAM have aroused extensive *** the perspective of the economy-wide analysis,this study uses a global computable general equilibrium model to explore the rationality of CBAM from the aspects of socioeconomic impact and the effects of promoting climate ***,the potential alternative mechanism of CBAM is *** results show that CBAM can reduce the EU's gross domestic product(GDP)loss;however,the GDP loss in all other regions ***,CBAM raises household welfare losses in most regions,including the ***,although CBAM can reduce the marginal abatement cost in eight regions,it comes at the cost of greater economic ***,the economic and household welfare cost of raising emissions reduction targets in regions like the USA and Japan is substantially higher than the impact of passively accepting the CBAM;therefore,CBAM's ability to drive ambitious emission reduction initiatives may be ***,for the potential alternative mechanism,from the perspective of reducing economic cost and household welfare losses,the EU could implement domestic tax cuts in the short-term and promote global unified carbon pricing in the long-term.

关键词： Border adjustment mechanism Computable general equilibrium model Carbon price Climate policy Global carbon pricing

Three-dimensional morphological characteristics measurement of ankle joint based on computed tomography image post-processing

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Chinese Medical Journal 2011年第23期124卷 3912-3918页

作者： CHEN Yan-xi LU Xiao-ling BI Gang YU Xiao HAO yi-li zhang kun ZOU Li-ling MEI Jiong YU Guang-rong Department of Orthopaedics Tongji Hospital of Tongji University Shanghai 200065 China

As precise positioning of ankle radiography is not possible, quantitative measurement of all syndesmotic parameters on repeated ankle X-ray films may be of little value. The purpose of this study was to provide a set of scientific and objective evaluation criteria for assessing the quality of ankle fracture reduction accurately and reliably by an intelligent combining three-dimensional （3-D） computed tomography （CT） measurement model. Methods From June 2008 to March 2011, all the thin-slice CT images of 100 cases （50 males and 50 females） with normal ankle joint scanned by 16-slice spiral CT were collected. Two-dimensional （2-D） and 3-D images of ankle joints were generated by using multiple planar reconstruction （MPR） and surface shaded display （SSD） respectively. The relevant parameters about bone structures and their relationship were measured and analyzed based on 3-D topological narrow division technique and 3-D measurement techniques combining essential elements of point, line and surface. Results In this study, the mean distance from lateral malleolus tip to talocrural articular surface, the tip of medial malleolus anterior colliculus to talocrural articular surface and lateral malleolus tip to the tip of medial malleolus anterior colliculus were （22.83±1.12） mm, （12.84±1.09） mm, and （61.18±2.03） mm respectively in male group, and （20.16±1.00） mm, （10.30±1.05） mm and （53.00±1.40） mm respectively in female group. The above three parameters were correlated with gender, height and weight （P 〈0.05）. However, the mean perpendicular distance from lateral malleolus tip to the plane through the tip of medial malleolus anterior colliculus, the talocrural angle, later clear space, medial clear space, and the superior clear space were （9.93±0.29） mm, （10.01±0.38）°, （1.94±0.16） mm, （2.78±0.19） mm, and （3.14±0.15） mm respectively in 100 cases, were not significance correlated with gender, height and weight （P 〉0.05）. Conclusions This study could provide a certain amount o

关键词： ankle, computed tomography three-dimensional reconstruction morphological characteristics

Comprehensive evaluation of rare case:From diagnosis to treatment of a sigmoid Schwannoma:A case report

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World Journal of Gastrointestinal Oncology 2024年第1期16卷 244-250页

作者： Jing-yi Li Xi-Zhuang Gao Jian zhang Xiang-Zheng Meng yi-Xian Cao kun Zhao Clinical Medical College of Jining Medical University Jining Medical UniversityJining 272000Shandong ProvinceChina Department of Gastroenterology The First People's Hospital of JiningJining 272000Shandong ProvinceChina

BACKGROUND Schwannomas are uncommon tumors originating from Schwann cells,forming the neural *** account for approximately 2%-6%of all mesenchymal tumors and are most commonly identified in peripheral nerve trunks,with rarity in the gastrointestinal *** gastrointestinal locations,the stomach harbors the majority of nerve sheath tumors,while such occurrences in the sigmoid colon are exceptionally *** SUMMARY This study presented a clinical case involving a 60-year-old female patient who,during colonoscopy,was diagnosed with a submucosal lesion that was later identified as a nerve sheath *** patient underwent surgical resection,and the diagnosis was confirmed through *** study highlighted an exceptionally uncommon occurrence of a nerve sheath tumor in the sigmoid colon,which was effectively managed within our ***,a comprehensive review of relevant studies was *** The preoperative diagnosis of nerve sheath tumors poses challenges,as the definitive diagnosis still relies on pathology and *** categorized as benign,these tumors have the potential to demonstrate malignant ***,the optimal treatment approach entails the complete surgical excision of the tumor,ensuring the absence of residual lesions at the margins.

关键词： Schwannoma Gastrointestinal stromal tumors Treatment Sigmoid colon Case report

A Fair and Trusted Trading Scheme for Medical Data Based on Smart Contracts

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Computers, Materials & Continua 2024年第2期78卷 1843-1859页

作者： Xiaohui Yang kun zhang School of Cyber Security and Computer Hebei UniversityBaoding071000China

Data is regarded as a valuable asset,and sharing data is a prerequisite for fully exploiting the value of ***,the current medical data sharing scheme lacks a fair incentive mechanism,and the authenticity of data cannot be guaranteed,resulting in low enthusiasm of participants.A fair and trusted medical data trading scheme based on smart contracts is proposed,which aims to encourage participants to be honest and improve their enthusiasm for *** scheme uses zero-knowledge range proof for trusted verification,verifies the authenticity of the patient’s data and the specific attributes of the data before the transaction,and realizes privacy *** the same time,the game pricing strategy selects the best revenue strategy for all parties involved and realizes the fairness and incentive of the transaction *** smart contract is used to complete the verification and game bargaining process,and the blockchain is used as a distributed ledger to record the medical data transaction process to prevent data tampering and transaction ***,by deploying smart contracts on the Ethereum test network and conducting experiments and theoretical calculations,it is proved that the transaction scheme achieves trusted verification and fair bargaining while ensuring privacy protection in a decentralized *** experimental results show that the model improves the credibility and fairness of medical data transactions,maximizes social benefits,encourages more patients and medical institutions to participate in the circulation of medical data,and more fully taps the potential value of medical data.

关键词： Blockchain data transactions zero-knowledge proof game pricing