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Longitudial observation of dynamic changes in cortical function and white matter fibrous structure of patients with visual pathway lesions by blood oxygenation level dependent-functional magnetic resonance imaging combined with diffusion tensor imaging

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Neural Regeneration Research 2007年第8期2卷 449-454页

作者： Hui Xiao Ziqian Chen Gennian qian ping Ni Youqiang Ye Jinhua Chen Department of MedicalRadiology Fuzhou GeneralHospital of Nanjing MilitaryArea Command of ChinesePLA Fuzhou 350025Fujian Province China

BACKGROUND： Functional magnetic resonance imaging （fMRI） is initially used for visual cortex location. However, the application of fMRI in investigating the development of visual pathway lesions needs to be further observed. OBJECTIVE： This study is to longitudially observe the dynamic changes in cortical function and white matter fibrous structure of patients with visual pathway lesions by blood oxygenation level dependent-functional magnetic resonance imaging （BOLD-fMRI） combined with diffusion tensor imaging （DTI）, and to analyze the characteristics of brain function and structural recombination at convalescent period of lesions. DESIGN： Randomized controlled observation. SETTING： Department of Radiology, the General Hospital of Nanjing Military Area Command of Chinese PLA. PARTICIPANTS： Eight patients with unilateral or bilateral visual disorder caused by visual pathway lesions, who admitted to Department of Radiology, the General Hospital of Nanjing Military Area Command of Chinese PLA from January to September 2006 were involved, and served as experimental subjects. The patients, 6 males and 2 females, were aged 16 - 67 years. They had visual disorder confirmed by clinical examination, i.e. visual pathway lesion, which was further diagnosed by MR or CT. Another 12 subjects generally matching to those patients of experimental group in gender, age and sight, who received health examination in synchronization were involved and served as controls. The subjects had no history of eye diseases. Their binocular visual acuity （or corrected visual acuity） was over 1.0. Both routine examination of ophthalmology and examination of fundus were normal. Informed consents of detected items were obtained from all the subjects. METHODS： Signa Excite HD 1.5T magnetic resonance imaging system with 16 passages （GE Company, USA） and coil with 8 passages were used; brain functional stimulus apparatus （SAV-8800. Meide Company） was used for showing experimental mission. At the early s

关键词： magnetic resonance imaging vision rehabilitation

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船用防污涂料研究进展

中国涂料 2024年第7期39卷 4-14页

作者：张春江刘保磊孟庆超钱程吴远程许驰冉千平江苏苏博特新材料股份有限公司南京211103 高性能土木工程材料国家重点实验室南京211103 辽宁苏博特船牌制漆有限公司沈阳110002 东南大学材料科学与工程学院江苏省土木工程材料重点实验室南京211189

综述了近年来船用防污涂料发展现状,简要讨论了船用防污涂料技术分类与防污机理,并对船用防污涂料常用防污性能测试方法进行了总结分析。最后,对船用防污涂料的发展方向进行了展望。

关键词：船舶涂料防污涂料防污机理研究进展

Upgrade of the magnetic diagnostic system for restart of HT-6M operation

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Chinese Physics B 2022年第12期31卷 347-355页

作者： Li-Xing Chen Biao Shen Da-Long Chen Zheng-ping Luo Zu-Chao Zhang Ying Chen Yong Wang Jin-ping qian Institute of Plasma Physics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230026China University of Science and Technology of China Hefei 230026China

The HT-6M tokamak at the Thailand Institute of Nuclear Technology has been *** order to ensure the smooth breakdown of plasma and obtain plasma discharge parameters,optimization of the poloidal field coils and upgrade of the magnetic diagnostics are described in this article.A perfect null field(stray field in the main chamber<10 G)is obtained using an ohmic heating *** obtain important information about the plasma,an external magnetic diagnostics system is designed and calibrated,including a Rogowski coil(measuring plasma current),a magnetic probe(measuring external field),diamagnetic loops(measuringβ_(p))and so *** order to realize high-frequency signal measurement and transmission,a series of frequency responses with the magnetic probe and transmission line are ***,to verify the null field,a fitting code is developed to reconstruct the stray field in the vacuum chamber based on magnetic probe measurements and flux *** results show that the error is within 1.5%.This indicates the accuracy of the magnetic measurement system and ensures the preparation for the breakdown of plasma.

关键词： HT-6M null field magnetic measurement high frequency calibration

The variation features of the Antarctic sea ice (Ⅱ)

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Acta Oceanologica Sinica 1994年第1期13卷 73-84页

作者： Xie Simei Hao Chunjiang qian ping and Zhang Lin

In this paper, on the basis of the Antarctic sea ice data from 1972 to 1989 issued by the America JointIce Center, the distribution features of the Antarctic sea ice is analyzed, the net sea ice area indexes are calculated,and the long-range variation periods of the sea ice area index are analyzed with the maximum entropy spectrum, finally the distribution pattern of the Antarctic sea ice and its variation features are *** to its spatial distribution feature, the Antarctic Sea ice is divided into three large regions. Region Ⅰ(0°～120°E) is a zonal area which includes the Prydz Bay area, and sea ice area extending from the Weddell Sea,Region Ⅱ (120°E～120°W) mainly includes the Ross Sea area, and Region Ⅲ (120°W～0°) mainly the WeddellSea area. Of all the regions, the ice area in Region Ⅲ is the largest, and that in Region Ⅰ is the *** the Antarctic,the seasonal changes of the sea ice are very obvious, during summer, in February, there isleast sea ice in the Southern Ocean, the net sea ice area (not include the area of open water) is about 3 190 000 km2,during winter, in September, there is most sea ice in the Southern Ocean, the area index is about 16 840 000 km2,nearly 5. 3 times of that in February. The seasonal change of sea ice is one month lag of the changes of the air temperature, but almost synchronous with that of *** all the three regions divided above, there are some points both common and uncommon in their sea icechange cycles, the common features are that there exist one and a half years, one year and ten-months secondaryperiods in all three regions, but their main periods are not the same, they are about 5, 11 and 6 a in Regions Ⅰ,Ⅱ,and Ⅲrespectively. The main periods of the sea ice change in Regions Ⅰand Ⅱ are very close because the ice areaextended eastward from the Weddell Sea ice area of Region Ⅲ is one of the main components of the Region Ⅰ. It isalso worth pointing out that in Region Ⅱ, southward extension of the Pacifi

关键词： The variation features of the Antarctic sea ice

Equilibrium Reinsurance Strategy and Mean Residual Life Function

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 758-777页

作者： Dan-ping LI Lv CHEN Lin-yi qian Wei WANG School of Statistics Key Laboratory of Advanced Theory and Application in Statistics and Data Science-MOEEast China Normal UniversityShanghai 200062China Academy of Statistics and Interdisciplinary Sciences Key Laboratory of Advanced Theory and Application in Statistics and Data Science-MOEEast China Normal UniversityShanghai 200062China School of Mathematics and Statistics Ningbo UniversityNingbo 315211China

In this paper,we analyze the relationship between the equilibrium reinsurance strategy and the tail of the distribution of the *** Mean Residual Life(MRL)has a close relationship with the tail of the distribution,we consider two classes of risk distributions,Decreasing Mean Residual Life(DMRL)and Increasing Mean Residual Life(IMRL)distributions,which can be used to classify light-tailed and heavy-tailed distributions,*** assume that the underlying risk process is modelled by the classical CramérLundberg model *** the mean-variance criterion,by solving the extended Hamilton-Jacobi-Bellman equation,we derive the equilibrium reinsurance strategy for the insurer and the reinsurer under DMRL and IMRL,***,we analyze how to choose the reinsurance premium to make the insurer and the reinsurer agree with the same reinsurance *** find that under the case of DMRL,if the distribution and the risk aversions satisfy certain conditions,the insurer and the reinsurer can adopt a reinsurance premium to agree on a reinsurance strategy,and under the case of IMRL,the insurer and the reinsurer can only agree with each other that the insurer do not purchase the reinsurance.

关键词： mean residual life excess-of-loss reinsurance insurer reinsurer stochastic control

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Treatment of Infertile Women with Unilateral Tubal Occlusion Diagnosed by Hysterosalpingography:The Role of Intrauterine Insemination

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Current Medical Science 2020年第4期40卷 767-772页

作者： Yi-hua LIN Jing-xin YE Ze-xuan WU Yun CHEN Xi XIA Wei-ping qian Department of Reproductive Center Peking University Shenzhen HospitalShenzhen 518036China Department of Ultrasound Peking University Shenzhen HospitalShenzhen 518036China

Summary:The optimal assisted reproductive treatment strategy for infertile women with unilateral tubal obstruction remains *** investigate the role of intrauterine insemination(IUI)in the treatment of infertile women with unilateral tubal occlusion,the data of 148 couples were retrospectively collected and ***-eight infertile women with unilateral occlusion diagnosed by hysterosalpingography(HSG)were categorized as the study group and 70 others with unexplained infertility as the control *** study group was divided into a proximal occlusion subgroup and a mid-distal occlusion subgroup for further *** main outcomes,namely the clinical pregnancy rate(CPR),ongoing pregnancy rate(OPR),and live birth rate(LBR)per cycle,were *** results showed a tendency of lower CPR,OPR,and LBR in the study group than in the control group,without statistical *** investigations revealed that the unilateral proximal occlusion subgroup had similar CPR,OPR,and LBR as the control group,while the unilateral mid-distal occlusion subgroup had significantly lower CPR(5.1%vs.20.0%,P=0.035),OPR(5.1%vs.20.0%,P=0.035),and LBR(5.1%vs.20.0%,P=0.035)than the control *** conclusion,the clinical outcomes of IUI were worse in patients with unilateral tubal occlusion than in those with unexplained *** might be primarily caused by the worse outcome of patients with unilateral mid-distal tubal occlusion instead of proximal occlusion.

关键词： hysterosalpingography intrauterine insemination unilateral tubal factor infertility

MRI and diffusion tensor imaging in assessing correlation of activation of cortical motor function and manifestations of corticospinal tract with muscle strength in patients with ischemic stroke

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Neural Regeneration Research 2006年第1期1卷 56-59页

作者： Ziqian Chen Hui Xiao Biyun Zhang Gennian qian ping Ni Xizhang Yang Department of Medical Imaging Fuzhou General Hospital of Nanjing Military Area Command of Chinese PLA Fuzhou 350025Fujian Province China

BACKGROUND： Ischemic stroke is often followed by the abnormalities of neurons and corticospinal tract, which can lead to corresponding clinical symptoms and signs. Recently, with the continuous perfection of high-field MRI instrument, it becomes possible to assess and investigate the cortical function and structural reconstruction following stroke by using MRI and diffusion tensor imaging （DTI）. OBJECTIVE： To observe the cortical motor function and changes of corticospinal tracts by using MRI and DTI in the patients with ischemic stroke at acute period, compare with the normal subjects, and assess the damage of corticospinal tract and muscle strength.DESIGN ： A case-control observation.SETTING： Department of Medical Imaging, Fuzhou General Hospital of Nanjing Military Area Command of Chinese PLA. PARTICIPANTS ： Nine inpatients （5 males and 4 females） with injury of motor function induced by acute ischemic stroke were selected from Fuzhou General Hospital of Nanjing Military Area Command of Chinese PLA between August and December in 2005, they aged 16-87 years with an average of 51 years old, and those with obvious conscious disturbances and severe cognitive disorders were excluded. At the same time, nine healthy right-handed physical examinees matched by age and gender with the patients were also selected, and they all had no nervous disease, epilepsy, mental diseases, cerebrovascular abnormalities and injury history, etc. All the subjects were informed with the detected items and agreed to participate in. METHODS： All the 9 patients with ischemic stroke at acute period and 9 healthy subjects were examined with MRI and DTI.① A block-based design was used in the MRI, the passive finger-to-finger exercise was used as the stimulative task, and the static condition was taken as the baseline task. The GE 1.5T MRI system was used, all the data were processed after off-line, and analyzed with the SPM2 software, the association between the activated area and local

关键词： cortical tensor assessing cortex rehabilitation handed exercise epilepsy atter interrupted

Theoretical investigation of Ag_n@（ZnS）42（n=6-16） using first principles:Structural, electronic and optical properties

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Progress in Natural Science:Materials International 2019年第5期29卷 525-532页

作者： Qing Liu Hanyue Zhao Xiaoxu Wang Jinrong Huo Lu Li Panpan Gao ping qian Yanjing Su Nanxian Chen Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology Beijing Department of Physics University of Science and Technology Beijing Corrosion and Protection Center Key Laboratory for Environmental Fracture (MOE) University of Science and Technology Beijing Department of Physics Tsinghua University

Ag@ZnS nanoparticles display enhanced photocatalytic efficiency and good photoelectric properties compared to their single-component counterparts in the process of forming a core-shell structure using an Ag cluster as the inner core of a ZnS outer *** this study,first-principles calculations were used to investigate the structural,electronic,and optical properties of Ag_n@（ZnS）42（n=6-16）core-shell *** calculated results show significant even-odd oscillations in the structural stability,that is,Ag@ZnS nanostructures with an even number of Ag_n core atoms are relatively more stable than those with an odd number of core *** secondorder differences in the total energies（Δ2E）and the core-shell interaction energy Ecsindicate that a Ag12@（ZnS）42nanostructure is the most stable configuration.A significant red shift was found in Ag_n@（ZnS）42nanoparticles in the absorption spectrum compared with a（ZnS）48nanostructure,which is likely attributed to the strong electron interactions between the Ag core and the ZnS shell.

关键词： Core-shell structure DFT Optical properties Red shift phenomenon Electronic structure

Influence of composition and size on the thermodynamic stability and structural evolution of CuAlNi nanoclusters

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Progress in Natural Science:Materials International 2020年第4期30卷 477-484页

作者： Qing Liu Ye Su Keke Song Xiaoxu Wang Panpan Gao Chutian Wang Yuqin Xiao Xiaodong Jian ping qian Beijing Advanced Innovation Center for Materials Genome Engineering Beijing Key Laboratory for Magneto-Photoelectrical Composite and Interfere Science School of Mathematics and Physics University of Science and Technology Beijing National Supercomputer Center in Tianjin

The heating process for CuAlNi nanoclusters with cuboctahedral structure was studied by molecular dynamics simulation with the embedded atom method. A diffusionless martensitic transformation from the cuboctahedral(CO) to the icosahedral(ICO) structure before the melting point was found in some CuAlNi nanoclusters. The effects of element composition and cluster size on the thermodynamic stability and structural transformation of trimetallic nanoclusters were investigated. The results show that the CO–ICO transformation temperature was size-dependent and occurred only for small clusters. It was also observed that the CO–ICO transformation temperature firstly dropped and then raised as Al concentration increased, which may be strongly related to the release of excess energy. Furthermore, the surface segregation phenomenon was also observed that the lower surface energy components, such as Al and Cu atoms, segregated to the surface of CuAlNi nanoclusters. The changes in the melting points of Cu Al Ni nanoclusters with different alloy compositions and cluster sizes were also studied. And furthermore, the physical basis of structural transition of CuAlNi nanoclusters was discussed.

关键词： MD simulation Structural transformation Thermodynamic stability Alloy nanocluster Size effect