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Contribution of diffusion,perfusion and functional MRI to the disconnection hypothesis in subcortical vascular cognitive impairment

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Stroke & Vascular Neurology 2018年第3期3卷 131-139页

作者： qing Ye feng Bai Department of Neurology Affiliated Drum Tower HospitalNanjing University Medical SchoolNanjingJiangsuChina Jiangsu Province Stroke Center for Diagnosis and Therapy NanjingChina Nanjing Neuropsychiatry Clinic Medical Center NanjingChina Jiangsu Key Laboratory for Molecular Medicine Nanjing University Medical SchoolNanjingChina

Vascular cognitive impairment(VCI)describes all forms of cognitive impairment caused by any type of cerebrovascular *** identification of VCI is quite difficult due to the lack of both sensitive and specific *** damage to the white matter tracts,which connect the cortical and subcortical regions,has been shown in subcortical VCI(SVCI),the most common subtype of VCI that is caused by small vessel *** specific MRI sequences,including diffusion tensor imaging(DTI)and functional MRI(fMRI),have emerged as useful tools for identifying subtle white matter changes and the intrinsic connectivity between distinct cortical *** review describes the advantages of these two modalities in SVCI research and the current DTI and fMRI findings on *** DTI technique,a variety of studies found that white matter microstructural damages in the anterior and superior areas are more specific to ***,functional brain abnormalities detected by fMRI have also been mainly shown in anterior brain areas in *** characteristic distribution of brain abnormalities in SVCI interrupts the prefrontal-subcortical loop that results in cognitive impairments in particular domains,which further confirms the‘disconnection syndrome’*** addition,another MRI technique,arterial spin labelling(ASL),has been used to describe the disconnection patterns in a variety of conditions by measuring cerebral blood *** role of the ASL technique in SVCI research is also ***,the review proposes the application of multimodality fusion in the investigation of SVCI pathogenesis.

关键词： impairment subcortical diffusion

Systematics on production of superheavy nuclei Z=119-122 in fusion-evaporation reactions

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Nuclear Science and Techniques 2021年第10期32卷 59-71页

作者： Fei Niu Peng-Hui Chen Zhao-qing feng School of Physics and Optoelectronic Technology South China University of TechnologyGuangzhou 510640China College of Electrical Energy and Power Engineering Yangzhou UniversityYangzhou 225000China

The fusion dynamics of the formation of super-heavy nuclei were investigated thoroughly within the din-uclear system *** Monte Carlo approach was implemented in the nucleon transfer process to include all possible orientations,at which the dinuclear system is assumed to be formed at the touching configuration of dinuclear *** production cross sections of superheavy nuclei Cn,Fl,Lv,Ts,and Og were calculated and compared with the available data from *** evaporation residue excitation functions in the channels of pure neutrons and charged particles were systematically *** combinations of 44 Sc,48;50 Ti,49;51 V,52;54 Cr,58;62 Fe,and 62;64 Ni bombarding the actinide nuclides 238 U,244 Pu,248 Cm,247;249 Bk,249;251 Cf,252 Es,and 243 Am were calculated to produce the superheavy elements with Z¼119?*** obtained that the production cross sections sensitively depend on the neutron richness of the reaction *** structure of the evaporation residue excitation function is related to the neutron separation energy and fission barrier of the compound nucleus.

关键词： Dinuclear system model Fusion-evaporation reactions Superheavy nuclei Cross sections

Effects of Titanium and Silicon on the Swelling Behavior of 15–15Ti Steels by Heavy-Ion Beam Irradiation

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Acta Metallurgica Sinica(English Letters) 2017年第11期30卷 1049-1054页

作者： Ai-Bing Du Wei feng Hai-Liang Ma Tian Liang da-qing Yuan Ping Fan Qiao-Li Zhang Chen Huang China Institute of Atomic Energy Beijing 102413 China Institute of Metal Research Chinese Academy of SciencesShenyang 110016 China

The swelling behavior of 20% cold-worked 15-15Ti steels with （0.23-0.40） wt% titanium and （0.42-0.81） wt% silicon content after heavy-ion beam irradiation has been investigated by transmission electron microscopy. The results show that 15-15Ti steel with higher titanium content displays lower swelling. As silicon content increases, the cavity size and the swelling of the 15-15Ti steels decrease obviously. Titanium and silicon may play important roles in suppressing the cavity nucleation and growth in 15-15Ti steel.

关键词： 15–15Ti Swelling Heavy-ion beam irradiation

High-temperature fracture behavior of MnS inclusions based on GTN model

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Journal of Iron and Steel Research International 2019年第9期26卷 941-952页

作者： Xin-gang Liu Can Wang qing-feng Deng Bao-feng Guo Key Laboratory of Advanced Forging and Stamping Technology and Science (Yanshan University) Ministry of Education of ChinaQinhuangdao 066004HebeiChina

The influence of the MnS plastic inclusion on the accumulation of internal damage was considered, and the Gurson– Tvergaard–Needleman (GTN) model was calibrated based on the finite element inverse method and image analysis method using ABAQUS and GTN models. The modified GTN damage model was used to simulate the initiation and propagation of cracks in an as-cast 304 stainless steel with MnS inclusions at 900 C. The simulation results agreed well with the experimental results, indicating that the model can be effectively applied to examine the high-temperature fracture behavior of MnS inclusions. The simulation and high-temperature tensile test results revealed that MnS inclusions increased the number of holes initiation and the probability of hole polymerization, reduced the crack propagation resistance, accelerated the occurrence of material fracture behavior, and were closely related to the stress state at high temperatures. When the stress triaxiality was low, the plastic strain in the metal matrix was high, and the MnS plastic inclusions accelerated the polymerization of the pores, making metal fracture failure more likely. On the other hand, when the stress triaxiality was high, the stress state in the metal matrix was biased to the tensile state, the plastic strain in the metal matrix was low, and the influence of MnS plastic inclusions on the fracture behavior was not evident.

关键词： MnS inclusion GTN model Tension High-temperature fracture behavior Crack initiation Crack propagation Stress

A Novel Photoproduct of Thymine in Phosphate-buffered Saline under Far UV Irradiation

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Chinese Chemical Letters 2003年第12期14卷 1233-1235页

作者： feng LIN qing Ling MA Department of Chemistry Xi-xi CampusZhejiang UniversityHangzhou 310028

The photolysis of thymine in phosphate-buffered saline (PBS, pH 8.0) under the irradiation of medium pressure mercury lamp (MPML) produces a novel compound C5H7N2O6P. The composition and structure of the compound hav... 详细信息

关键词： UV photolysis thymine phosphate-buffered saline (PBS).

Pion Cloud Effects on △-N Mass Splitting from Quark Models

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Communications in Theoretical Physics 2002年第8期38卷 189-194页

作者： DONG Yu-Bing feng qing-Guo Institute of High Energy Physics the Chinese Academy of Sciences P.O. Box 918-4 Beijing 100039 China Institute of High Energy Physics the Chinese Academy of Sciences P.O. Box 918-4 Beijing 100039 China

Pion cloud effects on △-N mass splitting are studied based on quark models. Pseudo-scalar pion-quarkcoupling is discussed in the relativistic and nonrelativistic frameworks. We separately calculate the pion cloud effects bythe one-pion exchange potential and by another method which is consistent with the baryon chiral perturbation *** able discrepancy in the mass splitting between the two methods is shown.

关键词： quark models, coupling constants, pion cloud, △-N mass splitting

Induction of Apoptosis by L-NMMA,via FKHRL1/ROCK Pathway in Human Gastric Cancer Cells

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Biomedical and Environmental Sciences 2006年第4期19卷 285-291页

作者： YONG-ZHONG WANG ZHEN-qing feng Department of Pathology Nanjing Medical University Nanjing 210029 Jiangsu China

Objective To investigate the apoptosis-inducing effect of endogenous nitric oxide （NO） suppression in gastric cancer cells and its mechanisms. Methods Apoptosis of gastric cancer cells was detected by flow cytometry. Expression of phosphorylated FKHRL1 （thr-32, ser-253） and FKHRL1 in gastric cancer cells was analyzed using Western blotting. Immunofluorescence assay was performed to localize the intracellular phosphorylated FKHRL1 （thr-32, ser-253） and FKHRL 1. Transfection of FKHRL1-HA wild type and mutant FKHRL1-HA T32A constructs was performed by lipofectamine plus reagent. NO generation was determined by Griess reaction. Results Gastric cancer cells were significantly apoptotic after treatment with NG-monomethyl-L-arginine （L-NMMA, a nitric oxide synthase inhibitor）, compared with the control （P〈0.01）. The apoptosis of gastric cancer cells induced by L-NMMA was dose-dependent and time-independent. However, the Z-DEVD-fmk, a caspase-3, 6, 7, 8, l0 inhibitor, did not prevent the apoptosis. The immunofluorescence assays showed that FKHRL1 protein was strongly expressed in the nucleu and p-FKHRL1 thr-32 protein was ：strongly expressed in the cytoplasm of SGC-7901 cells when endogenous nitric oxide generation was blocked by L-NMMA, but no change in FKHRL1 ser-253 phosphorylation. Nevertheless, ROCK protein was strongly expressed in p-FKHRL1 thr-32-positive SGC-7901 cells. The wortmannin, an inhibitor of phosphoinositol-3-OH kinase （PI3K）, did not block the phosphorylated FKHRL1 thr-32 protein induced by L-NMMA. However, Y-27632, a specific inhibitor of the protein kinase ROCK, significantly blocked apoptosis induced by phosphorylated FKHRL1 thr-32 （P〈0.01）, which was mediated by L-NMMA. A significant decrease in NO generation （P〈0.01） and a significant increase in apoptosis （P〈0.01） were observed when FKHRL1-HA wild-type cells were transfected, which caused increased FKHRL1 thr-32 phosphorylation. Conclusions L-NMMA triggers gastric carcinoma cell apoptosis, possibly

关键词： Gastric carcinoma Nitric oxide FKHRL1 Apoptosis Signaling

Hua's Theorem with s Almost Equal Prime Variables

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Acta Mathematica Sinica,English Series 2009年第7期25卷 1145-1156页

作者： qing feng SUN Heng Cai TANG Department of Mathematics Shandong University Ji'nan 250100 P. R. China

It is proved unconditionally that every sufficiently large positive integer satisfying some necessary congruence conditions can be represented as the sum of s almost equal k-th powers of prime numbers for 2 ≤ k ≤ 10... 详细信息

关键词： the additive theory of prime numbers short intervals circle method

Real-time accurate Free-Form Deformation in terms of triangular Bézier surfaces

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Applied Mathematics(A Journal of Chinese Universities) 2014年第4期29卷 455-467页

作者： CUI Yuan-min feng Jie-qing State Key Lab of CAD&CG Zhejiang University

We implemented accurate FFD in terms of triangular Bezier surfaces as matrix multiplications in CUda and rendered them via OpenGL. Experimental results show that the proposed algorithm is more efficient than the previ... 详细信息

关键词： accurate Free-Form Deformation GPU acceleration CUda triangular B@zier surface.