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Acta metallurgica Sinica(English Letters) 2024年第2期37卷 293-307页

作者： Hong-Jiang Wan Xiao-Qi Wu Hong-Liang Ming Jian-Qiu Wang En-Hou Han School of Materials Science and Engineering University of Science and Technology of ChinaShenyang110016China CAS Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of Materials Science and Engineering Northeastern UniversityShenyang110819China institute of Corrosion Science and Technology Guangzhou510530China

The effects of hydrogen charging time and pressure on the hydrogen embrittlement(HE)susceptibility of X52 pipeline steel material are studied by slow strain rate tensile *** fracture morphologies of the specimens are observed by scanning electron *** HE susceptibility of the X52 pipeline steel material increases with an increase in both hydrogen charging time and hydrogen *** a charging time of 96 h,the HE susceptibility index reaches 45.86%,approximately 3.6 times that at a charging time of 0 ***,a charging pressure of 4 MPa results in a HE susceptibility index of 31.61%,approximately 2.5 times higher than that at a charging pressure of 0.3 MPa.

关键词： Hydrogen embrittlement X52 pipeline steel material Tubular specimen Hydrogen charging time Hydrogen charging pressure

Neural stem cells promote neuroplasticity: a promising therapeutic strategy for the treatment of Alzheimer’s disease

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Neural Regeneration research 2024年第3期19卷 619-628页

作者： Jun Chang Yujiao Li Xiaoqian Shan Xi Chen Xuhe Yan Jianwei Liu Lan Zhao First Teaching Hospital of Tianjin University of Traditional chinese Medicine TianjinChina National Clinical research Center for chinese Medicine Acupuncture and Moxibustion TianjinChina Tianjin University of Traditional chinese Medicine TianjinChina

Recent studies have demonstrated that neuroplasticity,such as synaptic plasticity and neurogenesis,exists throughout the normal lifespan but declines with age and is significantly impaired in individuals with Alzheimer’s ***,promoting neuroplasticity may represent an effective strategy with which Alzheimer’s disease can be *** to their significant ability to self-renew,differentiate,and migrate,neural stem cells play an essential role in reversing synaptic and neuronal damage,reducing the pathology of Alzheimer’s disease,including amyloid-β,tau protein,and neuroinflammation,and secreting neurotrophic factors and growth factors that are related to *** events can promote synaptic plasticity and neurogenesis to repair the microenvironment of the mammalian ***,neural stem cells are considered to represent a potential regenerative therapy with which to improve Alzheimer’s disease and other neurodegenerative *** this review,we discuss how neural stem cells regulate neuroplasticity and optimize their effects to enhance their potential for treating Alzheimer’s disease in the clinic.

关键词： Alzheimer’s disease amyloid-β cell therapy extracellular vesicle neural stem cell synaptic plasticity tau

Regulating photocatalytic overall water splitting of ferroelectric heterostructures by size effect

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Nano research 2024年第9期17卷 8000-8006页

作者： Zixing Ye Daifu Yu Ruian Zhang Fei Qin Yiran Sun Jie Huang Zhanqi Zhou He Tian Gaorong Han Zhaohui Ren Gang Liu State Key Laboratory of Silicon and Advanced Semiconductor Materials School of Materials Science and EngineeringZhejiang UniversityHangzhou 310027China Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Center of Electron Microscopy School of Materials Science and EngineeringZhejiang UniversityHangzhou 310027China

In the past decade,ferroelectric materials have been intensively explored as promising *** intriguing ability of ferroelectrics is to directly sperate the photogenerated electrons and holes,which is believed to arise from a spontaneous *** how polarization affects the photocatalytic performance is vital to design high-efficiency *** this work,we report a size effect of ferroelectric polarization on regulating the photocatalytic overall water splitting of SrTiO_(3)/PbTiO_(3)nanoplate heterostructures for the first *** was realized hydrothermally by controlling the thickness and thus spontaneous polarization strength of single-crystal and single-domain PbTiO_(3)nanoplates,which served as the substrate for selective heteroepitaxial growth of SrTiO_(3).An enhancement of 22 times in the photocatalytic overall water splitting performance of the heterostructures has been achieved when the average thickness of the nanoplate increases from 30 to 107 nm.A combined experimental investigation revealed that the incompletely compensated depolarization filed is the dominated driving force for the photogenerated carrier separation within heterostructures,and its increase with the thickness of the nanoplates accounts for the enhancement of photocatalytic ***,the concentration of oxygen vacancies for negative polarization compensation has been found to grow as the thickness of the nanoplates increases,which promotes oxygen evolution reaction and reduces the stoichiometric ratio of H_(2)/O_(2).These findings may provide the opportunity to design and develop high-efficiency ferroelectric photocatalysts.

关键词： single-domain nanoplates size effect ferroelectric polarization screening photocatalytic overall water splitting

Comparative analysis of the rapid intensification of two super cyclonic storms in the Arabian Sea

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TROPICAL CYCLONE research AND REVIEW 2024年第1期13卷 41-54页

作者： Liu, Longsheng Huang, Yiwu Liu, Lian Natl Meteorol Ctr Beijing Peoples R China chinese acad Sci Inst Tibetan Plateau Res Beijing Peoples R China

A comparative analysis of the rapid intensification (RI) of super cyclonic storms Chapala (2015) and Kyarr (2019) in the Arabian Sea is conducted using the North Indian Ocean tropical cyclone data, microwave sounding images, the NOAA OISST data and the ERA5 reanalysis data. Results show that the subtropical westerly jet stream and the Southern Hemisphere anticyclonic circulation led to the formation of an obvious double -channel outflow from the northern and southern sides of the two storm centers, and the substantial inflow appeared at the eastern boundary layer of both storms. These promoted the vertical ascent motion and release of the latent heat of condensation. A warm sea surface is a necessary but not dominant factor for the RI of cyclonic storms in the Arabian Sea. During the RI of Chapala and Kyarr, the deep vertical wind shear was less than 10 m s-1; moreover, the mid -level humidity conditions favored the RI of the two cyclonic storms. Chapala had a single warm core, whereas Kyarr had double warm cores in the vertical direction. The impacts of the latent heat of fusion is more obvious for Chapala, and the potential vorticity in its inner core increases from 4.4 PVU to 8.8 PVU, whereas the potential vorticity and vorticity in the inner core of Kyarr do not change significantly. Microwave detection images show that both Chapala and Kyarr were accompanied by the formation of eyewalls during the RI phase, and the radius of maximum wind decreased and the maximum wind speed increased during the eyewall-thinning process. Both Chapala and Kyarr passed through a positive anomaly region of maximum potential intensity during the RI phase, which increases the possibility to develop to higher intensity after genesis. (c) 2024 The Shanghai Typhoon institute of China Meteorological Administration. Publishing services by Elsevier B.V. on behalf of KeAi Communication Co. Ltd. This is an open access article under the CC BY -NC -ND license (http://***/licens

关键词： Super cyclonic storm Rapid intensification Upper-level outflow Potential vorticity MPI LARGE-SCALE CHARACTERISTICS WESTERN NORTH PACIFIC INTENSIFYING TROPICAL CYCLONES HURRICANE BONNIE 1998 VERTICAL WIND SHEAR STATISTICAL-ANALYSIS PART II ENVIRONMENTAL-CONTROL NUMERICAL-SIMULATION INDIAN-OCEAN

The weakening effect of urbanization on tropical cyclone surface winds : An observational study for Shanghai

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TROPICAL CYCLONE research AND REVIEW 2024年第1期13卷 15-23页

作者： Zhang, Lechuan Yu, Hui Ao, Xiangyu Tang, Shengming chinese acad Meteorol Sci Beijing Peoples R China China Meteorol Adm Shanghai Typhoon Inst Shanghai Peoples R China

The observation -reanalysis difference method (OMR) and wind pro fi le fi tting method were used to analyze the in fl uence urbanization has on the near -surface wind speed in Shanghai during tropical cyclone events. The data used include daily wind speed data from the Shanghai Meteorological Observatory Station collected from 1991 to 2020, hourly wind speed data from 100 m high wind towers from 2017 to 2019, and reanalysis data that covered the same period. The results indicated that during tropical cyclone occurrence, the wind speed of the OMR in the central urban region was signi fi cantly lower than that in the suburban area, and the OMR declined more obviously over the year, down to - 8 m/s in 2020. Urbanization leads to the increase of average wind weakening rate to be higher than the maximum wind weakening rate, causing the maximum weakening rate of the central urban region to the average wind over 80%, while maximum wind speed was less than 80%. The weakening rate of both the average and maximum wind speeds during tropical cyclone impacts is greater than the rate that the annual average wind speed was reduced. A logarithmic variation was visible in the wind pro fi le of the island station during tropical cyclone occurrence, with an average friction velocity U * of 0.9389 m/s and an average rough length Z 0 of 0.4915 m. The wind speed during tropical cyclone events was higher than the three-year average wind speed within each layer. The suburban stations show a linear variation, and every hundred meters of height results in an increase of 5 - 6 m/s in the wind speed change rate. At 100 m of altitude, the wind speed in the suburban region is reduced by approximately 40%. (c) 2024 The Shanghai Typhoon institute of China Meteorological Administration. Publishing services by Elsevier B.V. on behalf of KeAi Communication Co. Ltd. This is an open access article under the CC BY -NC -ND license (http://***/licenses/by-nc-nd/4.0/).

关键词： Urbanization Tropical cyclone Shanghai Wind speed SPEED

Electroacupuncture ameliorates blood-brain barrier disruption after ischemic stroke through histone acetylation regulation at the matrix metalloproteinase 9 and tissue inhibitor of metalloproteinase 2 genes

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Journal of Traditional chinese Medicine 2024年第4期44卷 734-744页

作者： CHEN Yonglin OUYANG Ling MENG Lingling WU Bufan PENG Rou LIU Sitong HOU Dan WANG Yaling JING Xinyue LU Shengfeng FU Shuping Key Laboratory of Acupuncture and Medicine research of Ministry of Education Nanjing University of Chinese MedicineNanjing 210023China

OBJECTIVE:To explore whether the regulation of matrix metalloproteinase 9(MMP-9)/tissue inhibitors of MMPs(TIMPs)gene expression through histone acetylation is a possible mechanism by which electroacupuncture(EA)protects blood-brain barrier(BBB)integrity in a middle cerebral artery occlusion(MCAO)rat ***:Male Sprague-Dawley rats were divided into four groups:the sham group,the MCAO group,the MCAO+EA(MEA)group,and the MCAO+EA+HAT inhibitor(HATi)*** MCAO model was generated by blocking the middle cerebral *** was applied to Baihui(GV20).Samples were collected 1 or 3 d after *** function scores and Evans blue extravasation were employed to evaluate the poststroke *** effect of EA on MMP-9/TIMPs gene expression was assessed by real-time fluorescence quantitative polymerase chain reaction(RT-qPCR)and chromatin immunoprecipitation(ChIP).RESULTS:Our results showed that EA treatment prominently improved neurological function and ameliorated BBB *** RT-qPCR assay showed that EA reduced the expression of MMP-9 and promoted TIMP-2 mRNA expression,but HATi reversed these effects of *** addition,ChIP results revealed that EA decreased the enrichment of H3K9ace/H3K27ace at MMP-9 promoters and notably stimulated the recruitment of H3K9ace/H3K27ace at TIMP-2 ***:EA treatment at Baihui(GV20)regulates the transcription of MMP-9 and TIMP-2 through histone acetylation modification in the acute stage of stroke,which preserves the structural integrity of the BBB in MCAO *** findings suggested that the histone acetylation-mediated transcriptional activity of target genes may be a crucial mechanism of EA treatment in stroke.

关键词： blood-brain barrier matrix metalloproteinase 9 tissue inhibitor of metalloproteinases electroacupuncture histone acetylation

Fast X-ray imaging beamline at SSRF

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Nuclear Science and Techniques 2024年第9期35卷 68-81页

作者： Ke Li Hong-Lan Xie Ya-Nan Fu Fei-Xiang Wang Guo-Hao Du Jian-Feng ji Biao Deng Ti-Qiao Xiao Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China

The fast X-ray imaging beamline(BL16U2)at Shanghai Synchrotron Radiation Facility(SSRF)is a new beamline that provides X-ray micro-imaging capabilities across a wide range of time scales,spanning from 100 ps toμs and *** beamline has been specifically designed to facilitate the investigation of a wide range of rapid phenomena,such as the deformation and failure of materials subjected to intense dynamic *** addition,it enables the study of high-pressure and high-speed fuel spray processes in automotive *** light source of this beamline is a cryogenic permanent magnet undulator(CPMU)that is cooled by liquid *** CPMU can generate X-ray photons within an energy range of 8.7-30 *** beamline offers two modes of operation:monochromatic beam mode with a liquid nitrogen-cooled double-crystal monochromator(DCM)and pink beam mode with the first crystal of the DCM out of the beam *** X-ray imaging methods were implemented in BL16U2:single-pulse ultrafast X-ray imaging,microsecond-resolved X-ray dynamic imaging,millisecond-resolved X-ray dynamic micro-CT,and high-resolution quantitative ***,BL16U2 is equipped with various in situ impact loading systems,such as a split Hopkinson bar system,light gas gun,and fuel spray *** the completion of the final commissioning in 2021 and subsequent trial operations in 2022,the beamline has been officially available to users from 2023.

关键词： Multiple time-scale X ray imaging Single-pulse X ray imaging Dynamic 2D imaging Dynamic micro-CT

Influence of Post-Treatment Process on Microstructure and Properties of Laser Additively Manufactured Nickel-Based Superalloy

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稀有金属材料与工程 2024年第9期53卷 2478-2484页

作者： Chen Shuang Yang Yanhong Guo Zhiqiang Liang Jingjing Li Jinguo Zhou Yizhou School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China institute of metal research Chinese Academy of SciencesShenyang 110016China

Defects such as cracks and micropores exist in nickel-based superalloy during laser powder bed fusion(LPBF),hindering their application in various *** isostatic pressing(HIP)was combined with conventional heat treatment(HT)to obtain LPBF nickel-based superalloy parts with ideal properties and fewer *** results show that HIP process can improve the densification,while the conventional HT can eliminate the micro-defects to improve the mechanical *** HIP treatment,the defect volume fraction of LPBF specimens *** HT,the defect content of HIP+HT specimens increases *** post-treatment,the hardness shows a decreasing trend,and the tensile strength and post-break elongation of HIP+HT specimens increase to 1326 MPa and 21.3%,respectively,at room temperature.

关键词： nickel-based superalloy laser powder bed fusion post-treatment microstructure properties

Transcriptomic analysis reveals the effects of maternal exposure to bisphenol AF on hypothalamic development in male neonatal mice

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Journal of Environmental Sciences 2024年第7期141卷 304-313页

作者： Lin Lv Yuanyuan Li Xuanyue Chen Zhanfen Qin State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of chinese academy of Sciences Beijing 100049China

Fragmented data suggest that bisphenol AF(BPAF),a chemical widely used in a variety of products,might have potential impacts on the ***,we employed male neonatal mice following maternal exposure to explore the effects of low-dose BPAF on hypothalamic development by *** found that maternal exposure to approximately 50μg/(kg·day)BPAF from postanal day(PND)0 to PND 15 altered the hypothalamic transcriptome,primarily involving the pathways and genes associated with extracellular matrix(ECM)and intercellular adhesion,neuroendocrine regulation,and neurological *** RNA analysis confirmed the changes in the expression levels of concerned ***,we further revealed that low-dose BPAF posed a stimulatory impact on pro-opiomelanocortin(POMC)neurons in the arcuate nucleus of the hypothalamus and induced the browning of inguinal white adipose *** findings indicate that developmental exposure to low-dose BPAF could interfere with hypothalamic development and thereby lead to alterations in the ***,5000μg/(kg·day)BPAF caused slighter,non-significant or even inverse alterations than the low dose of 50μg/(kg·day),displaying a dose-independent *** observations suggest that the the dose-independent effects of BPAF might be associated with oxidative stress and inflammatory responses caused by the high ***,our study highlights a risk of low-dose BPAF to human neuroendocrine regulation and metabolism.

关键词： Bisphenol AF Hypothalamus Transcriptomic alteration Pro-opiomelanocortin(POMC)neurons White adipose tissue browning

Developing a novel quantitative parameter for characterizing spatial distribution of fish following exposure to chemicals and wastewater:Behavioral Gini coefficient

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Journal of Environmental Sciences 2024年第7期141卷 129-138页

作者： Xuanyue Chen Yuanyuan Li Zhanfen Qin State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of chinese academy of Sciences Beijing 100049China

While the spatial distribution pattern of fish is increasingly used for toxicological test o chemicals or wastewater,no ideal parameter is available for quantitative assessment of spa tial distribution,especially uneven distribution with multiple ***,to develop a quantitative assessment parameter for spatial distribution,the zebrafish were exposed to ethanol,pentylenetetrazole(PTZ),paraquat dichloride(paraquat)and wastewater,followed by a behavioral test in a narrow *** data was acquired and analyzed by id Tracker and *** comparing the effects of all treatments on behavior parameters we confirmed that the spatial distribution was more easily altered rather than general loco motor parameters,e.g.0.7-70 mg/L PTZ and 5-20 mg/L paraquat being effective for altering spatial distribution but having little effects on general locomotor *** on the heatmap,i.e.,the cumulative proportion of grids and that of frequency in grids,we calcu lated the behavioral Gini coefficient(G_(b))for quantitative assessment of fish spatial distri *** Gini coefficient ranged from zero to 1,with larger values meaning poorer even ness of spatial *** note,G_(b)showed smaller coefficient of variations(CV)with3%-19%between replicate tanks in all treatments than the highest frequency(4%-79%),dis playing well ***,G_(b)addressed the challenge of the complicated heatmap with multiple ***,the behavioral Gini coefficient we established is an idea parameter to quantitatively assess spatial distribution of fish shoal,which is expected to be applied in toxicity testing for chemicals and wastewater and automatic quality monitoring for surface water and aquaculture water.

关键词： Zebrafish Behavioral test Spatial distribution Behavioral Gini coefficient