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Surface photometry and radial color gradients of nearby luminous early-type galaxies in SDSS Stripe 82

Research in Astronomy and Astrophysics 2011年第3期11卷 309-326页

作者： fang-zhou jiang Song Huang Qiu-Sheng Gu Department for Intensive Instruction Kuang Yaming Honors School Nanjing University Nanjing 210093 China Department of Astronomy Nanjing University Nanjing 210093 China

We make use of the images from the Sloan Digital Sky Survey Stripe 82（Stripe 82） to present an analysis of r band surface brightness profiles and radial color gradients（g-r,u-r） in our sample of 111 nearby early-type galaxies（ETGs） .Thanks to the Stripe 82 images,each of which is co-added from about 50 single frames,we are able to pay special attention to the low-surface-brightness areas（LSB areas） of the *** LSB areas affect the Sérsic fittings and concentration indices by making both of the indices less than the typical values for *** the Sérsic fits to all the surface brightness profiles,we found some Sérsic indices that range from 1.5 to 2.5,much smaller than those of typical de Vaucouleur profiles and relatively close to those of exponential disks,and some others much larger than four but still with accurate *** galaxies cannot be fitted with a single Sérsic profile,but once we try double Sérsic profiles,the fittings are improved：one with a profile relatively close to the de Vaucouleur law in the inner area and a profile relatively close to an exponential law in the LSB area,the other with a nice fitting in the inner area but still having a failed fitting in the outer *** 60%of the sample has negative color gradients（red-core） within 1.5Re,much more than the approximately 10%positive ones（blue-core） within the same ***,taking into account the LSB areas,we find that the color gradients are not necessarily monotonic：about one third of the red-core（or blue-core） galaxies have positive（or negative） color gradients in the outer areas. So LSB areas not only make ETGs’Sérsic profiles deviate from de Vaucouleur ones and shift to the disk end,but also reveal that quite a number of ETGs have opposite color gradients in inner and outer *** outcomes remind us of the necessity of double-Sérsic *** LSB phenomena may be interpreted by mergers and thus have different metallicity in the outer *** parameters ar

关键词： galaxies:early-type galaxies—galaxies:surface brightness profiles and color gradients—techniques:photometric

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Bis(7)-Tacrine, a Promising Anti-Alzheimer's Agent,Attenuates Glutamate-Induced Cell Injury in Primary Cultured Cerebrocortical Neurons of Rats

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Wuhan University Journal of Natural Sciences 2001年第3期6卷 737-741页

作者： Zhang Bai fang,Peng fang fang,Zhang jiang zhou,Wu Dong cheng  Biochemistry Department, School of Medicine, Wuhan University, Wuhan 430071, China Wuhan University Biochemistry Department School of Medicine Wuhan China (GRID:grid.49470.3e) (ISNI:***)

The effects of bis(7) tacrine, a novel dimeric acetylcholinesterase (AChE) inhibitor, on glutamate induced cell injury were investigated in primary cerebral cortical neurons of rats. Exposure of cultured neurons (12 days after plating) to 0.5 mmol/L glutamate for 30 min resulted in significant cell damage. Pretreatment with bis(7) tacrine (0.03 1.0 μmol/L) reduced the glutamate induced neurotoxicity in a concentration dependent manner and the maximal response was seen at 1 μmol/L with approximately 30% protection. A receptor binding assay showed that bis(7) tacrine can completely displace MK 801 binding to rat cortical membrane with an IC 50 of 0.57 μmol/L. These findings suggest that bis(7) tacrine can directly interact with N methyl D aspartate receptor channel complex, which may contribute to the inhibitor's protective effects against glutamate induced excitotoxicity. Thus, it is possible that anti glutamate/anti AChE synergism is responsible for potentially better Alzheimer's therapy of bis(7) tacrine relative to tacrine.

关键词： bis(7) tacrine tacrine cholinesterase inhibitor glutamate primary neuronal cell culture

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Ultrafast optical investigation of carrier and spin dynamics in low-dimensional perovskites

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Science China(Technological Sciences) 2024年第1期67卷 2-18页

作者： FU JinYue jiang Ying fang HongHua Key Laboratory for Micro-Nano Physics and Technology of Hunan Province School of Physics and ElectronicsHunan UniversityChangsha 410012China State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision InstrumentTsinghua UniversityBeijing 100084China

Low-dimensional perovskite(PVK)materials have attracted significant research interest,because of their quantum-confined effect,tunable band gap structures,and higher stability than that of three-dimensional(3D)*** semiconductor optoelectronic devices,high speed and small size are closely *** development of high-speed devices requires researchers to fully understand the properties of materials,especially the dynamic processes such as carrier recombination,separation,and transport,which often play a crucial role in the performance of *** an indispensable part of dynamic research,spin relaxation is also of great significance in studying the properties of materials and explore possible *** halide PVK materials have strong spin-orbit coupling(SOC),which provides a basis for information storage and processing by using spin degrees of ***,studying the carrier and spin dynamics of low-dimensional PVKs is an effective way to understand the internal properties of low-dimensional PVKs *** paper summarizes the latest research progress on the ultrafast carrier and spin dynamics in low-dimensional PVKs,to comprehensively understand their carrier and spin behaviors and present an outlook for relevant studies in this area.

关键词： low-dimensional perovskites carrier dynamics spin dynamics optoelectronic devices

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Weighted multilinear p-adic Hardy operators and commutators on p-adic Herz-type spaces

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Applied Mathematics(A Journal of Chinese Universities) 2024年第3期39卷 554-570页

作者： MA Teng zhou jiang College of Mathematics and System Sciences Xinjiang UniversityUrumqi 830046China

In this paper,we introduce the weighted multilinear p-adic Hardy operator and weighted multilinear p-adic Ces`aro operator,we also obtain the boundedness of these two operators on the product of p-adic Herz spaces and p-adic Morrey-Herz spaces,the corresponding operator norms are also established in each ***,the boundedness of commutators of these two operators with symbols in central bounded mean oscillation spaces and Lipschitz spaces on p-adic Morrey-Herz spaces are also given.

关键词： Morrey-Herz spaces weighted multilinear p-adic Hardy operator commutators operator norms

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Spatial-temporal patterns and evolution of carbon storage in China's terrestrial ecosystems from 1980 to 2020

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Science China Earth Sciences 2024年第10期67卷 3270-3287页

作者： Shaojian WANG Shijie zhou Chuanglin fang School of Geography and Planning Sun Yat-sen UniversityGuangzhou 510006China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China

Analyzing the changes in carbon storage in terrestrial ecosystems caused by land use changes is a crucial part of exploring the carbon cycle. In addition, enhancing carbon storage in terrestrial ecosystems is an effective and environmentally friendly measure to sequester anthropogenic carbon emissions, which is significant for achieving carbon neutrality and curbing global climate change. This paper uses land use data and carbon density tables with the In VEST model to obtain a carbon storage distribution map of China. It further applies land use response elasticity coefficients, Theil index multi-stage nested decomposition, and spatial autocorrelation analysis to examine the spatial-temporal patterns, causes of changes, and evolution characteristics of carbon storage in terrestrial ecosystems from 1980 to 2020. The results show that the temporal changes in China's carbon storage generally present an inverted S-curve, with an initial rapid decline followed by a slower decrease. Spatially, it features high levels in the northeast, low levels in the northwest, and a uniform distribution in the central and southern *** disturbance of land use type changes on terrestrial ecosystem carbon storage has been effectively mitigated. The significant reduction in grassland area in the Southwest region is the main source of carbon storage loss during the study period, and the encroachment of construction land on arable land in large urban agglomerations is one of the important causes of carbon storage loss. The Theil index multi-stage nested decomposition results indicate that the overall difference in carbon storage in China has decreased, while differences among cities within provinces and among counties within cities have increased. The influence of natural factors on the distribution of carbon storage is weakening, whereas the impact of human activities is becoming more profound, enhancing its influence on the spatial distribution of carbon storage in China. From 198

关键词： Terrestrial ecosystem carbon storage Carbon density Land use change InVEST model Spatiotemporal pattern

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Experimental and numerical study of buckling-restrained braces configured with out-of-plane eccentricity under cyclic loading

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Earthquake Engineering and Engineering Vibration 2024年第4期23卷 957-971页

作者： Cao Yongsheng zhou Yun Takagi Jiro jiang Ke Deng Xuesong fang Xiaojun Earthquake Engineering Research&Test Center Guangzhou UniversityGuangzhou 510006China School of Civil Engineering Guangzhou UniversityGuangzhou 510006China Guangdong Provincial Key Laboratory of Earthquake Engineering and Applied Technology Guangzhou 510006China Key Laboratory of Earthquake Resistance Earthquake Mitigation and Structural SafetyMinistry of EducationGuangzhou 510006China Graduate School of Urban Environmental Sciences Tokyo Metropolitan UniversityTokyo 192-0397Japan Department of Civil and Natural Resources Engineering University of CanterburyChristchurch CT13ANNew Zealand

This study focuses on variations in the hysteretic behavior of buckling-restrained braces(BRBs)configured with or without out-of-plane eccentricity under cyclic ***-static experiments and numerical simulations were carried out on concentrically and eccentrically loaded BRB specimens to investigate the mechanical properties,energy dissipation performance,stress distribution,and high-order deformation *** experimental and numerical results showed that compared to the concentrically loaded BRBs,the stiffness,yield force,cumulated plastic ductility(CPD)coefficient,equivalent viscous damping coefficient and energy dissipation decreased,and the yield displacement and compression strength adjustment factor increased for the eccentrically loaded *** the existence of the out-of-plane eccentricity,the initial yield position changes from the yield segment to the junction between the yield segment and transition segment under a tensile load,while the initial high-order buckling pattern changes from a first-order C-shape to a secondorder S-shape under a compressive load.

关键词： buckling-restrained brace out-of-plane eccentricity experiment numerical simulation mechanical properties

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A disk I/O optimized system for concurrent graph processing jobs

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Frontiers of Computer Science 2024年第3期18卷 13-29页

作者： Xianghao XU fang WANG Hong jiang Yongli CHENG Dan FENG Peng fang School of Computer Science and Engineering Nanjing University of Science and TechnologyNanjing 210094China Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074China Department of Computer Science&Engineering University of Texas at ArlingtonArlingtonTX 76019USA College of Computer and Data Science Fuzhou UniversityFuzhou 350108China Zhejiang Lab Hangzhou 311121China

In order to analyze and process the large graphs with high cost efficiency,researchers have developed a number of out-of-core graph processing systems in recent years based on just one commodity *** the other hand,with the rapidly growing need of analyzing graphs in the real-world,graph processing systems have to efficiently handle massive concurrent graph processing(CGP)***,due to the inherent design for single graph processing job,existing out-of-core graph processing systems usually incur unnecessary data accesses and severe competition of I/O bandwidth when handling the CGP *** this paper,we propose GraphCP,a disk I/O optimized out-of-core graph processing system that efficiently supports the processing of CGP *** proposes a benefit-aware sharing execution model to share the I/O access and processing of graph data among the CGP jobs and adaptively schedule the graph data loading based on the states of vertices,which efficiently overcomes above challenges faced by existing out-of-core graph processing ***,GraphCP adopts a dependency-based future-vertex updating model so as to reduce disk I/Os in the future *** addition,GraphCP organizes the graph data with a Source-Sorted Sub-Block graph representation for better processing capacity and I/O access *** evaluation results show that GraphCP is 20.5×and 8.9×faster than two out-of-core graph processing systems GridGraph and GraphZ,and 3.5×and 1.7×faster than two state-of-art concurrent graph processing systems Seraph and GraphSO.

关键词： graph processing disk I/O concurrent jobs

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A New Method for Deriving High-Vertical-Resolution Wind Vector Data from the L-Band Radar Sounding System in China

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Advances in Atmospheric Sciences 2024年第11期41卷 2192-2202页

作者： fang YUAN Zijiang zhou Jie LIAO National Meteorological Information Center China Meteorological AdministrationBeijing 100081China

High-vertical-resolution radiosonde wind data are highly valuable for describing the dynamics of the meso-and microscale atmosphere. However, the current algorithm used in China's L-band radar sounding system for calculating highvertical-resolution wind vectors excessively smooths the data, resulting in significant underestimation of the calculated kinetic energy of gravity waves compared to similar products from other countries, which greatly limits the effective utilization of the data. To address this issue, this study proposes a novel method to calculate high-vertical-resolution wind vectors that utilizes the elevation angle, azimuth angle, and slant range from L-band radar. In order to obtain wind data with a stable quality, a two-step automatic quality control procedure, including the RMSE-F(root-mean-square error F) test and elemental consistency test are first applied to the slant range data, to eliminate continuous erroneous data caused by unstable signals or radar malfunctions. Then, a wind calculation scheme based on a sliding second-order polynomial fitting is utilized to derive the high-vertical-resolution radiosonde wind vectors. The evaluation results demonstrate that the wind data obtained through the proposed method show a high level of consistency with the high-resolution wind data observed using the Vaisala Global Positioning System and the data observed by the new Beidou Navigation Sounding System. The calculation of the kinetic energy of gravity waves in the recalculated wind data also reaches a level comparable to the Vaisala observations.

关键词： L-band radar sounding system upper air high-vertical-resolution radiosonde wind vectors quality control polynomial fitting

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Winter-spring minimum temperature variations inferred from tree-ring δ^(13)C in southeastern China

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Journal of Forestry Research 2024年第5期35卷 182-190页

作者： Wenli Li Feifei zhou Heng Zhang Keyan fang Key Laboratory of Humid Subtropical Eco-Geographical Process(MOE) College of Geographic SciencesFujian Normal UniversityFuzhou 350007People’s Republic of China

Long-term temperature variations inferred from high-resolution proxies provide an important context to evaluate the intensity of current ***,tem-perature reconstructions in humid southeastern China are scarce and particularly lack long-term data,limiting us to obtain a complete picture of regional temperature *** this study,we present a well-verified reconstruction of winter-spring(January–April)minimum temperatures over southeastern China based on stable carbon isotopic(δ^(13)C)records of tree rings from Taxus wallichiana *** from 1860 to *** reconstruction accounted for 56.4%of the total observed *** periods occurred during the 1860s–1910s and 1960s–*** temperatures have had an upward trend since the 1920s,most of the cold extremes were in recent *** El Niño-Southern Oscillation(ENSO)variance acted as a key modulator of regional winter-spring minimum temperature ***,teleconnections between them were a nonlinear process,i.e.,a reduced or enhanced ENSO variance may result in a weakened or intensified temperature-ENSO relationship.

关键词： Tree rings Carbon isotope Southeastern China Extreme coldness El nino-southern oscillation

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Analysis of the role of dihydromyricetin derived from vine tea(Ampelopsis grossedentata)on multiple myeloma by activating STAT1/RIG-I axis

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Oncology Research 2024年第8期32卷 1359-1368页

作者： WEI jiang MEI zhou Department of Hematology Shaoxing Shangyu People’s HospitalShaoxing312000China Department of Hematology Zhuji People’s HospitalShaoxing311800China

Multiple myeloma(MM)is a plasma cell malignancy and remains incurable as it lacks effective curative approaches;thus,novel therapeutic strategies are desperately *** study aimed to explore the therapeutic role of dihydromyricetin(DHM)in MM and explore its *** MM and normal plasma samples,human MM cell lines,and normal plasma cells were used for in vitro *** counting kit-8(CCK-8),flow cytometry,and trans-well assays were performed for the assessment of cell viability,apoptosis,migration,and invasion,*** real-time polymerase chain reaction(qRT-PCR)was employed to assess the mRNA expression of signal transducer and activator of transcription 1(STAT1)and retinoic acid-inducible gene I(RIG-I).Western blotting was employed to assess E-cadherin,N-cadherin,signal transducer,STAT1,p-STAT1,and RIG-I protein expression.A tumor xenograft model was used for in vivo ***,dihydromyricetin(DHM)dose-dependently restrained viability,apoptosis,migration,and invasion,and facilitated apoptosis of U266 *** DHM treatment,the Ecadherin level was increased and the N-cadherin level was decreased in U266 and RPMI-8226 cells,suggesting the inhibitory effects of DHM on epithelial-mesenchymal transition(EMT)in ***,the levels of p-STAT1/STAT1 and RIG-I were down-regulated in ***,the STAT1 inhibitor fludarabine undid the suppressive effect of DMH on the malignant characteristics of U266 ***,DHM inhibited MM tumor growth and EMT,and activated STAT1/RIG-I pathway in ***,this study first revealed that DHM can restrain EMT and tumor growth in MM by activating STAT1/RIG-I signaling,which provides a novel drug for the treatment of MM.

关键词： Dihydromyricetin Multiple myeloma Epithelial-mesenchymal transition Tumor growth

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