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强震区装配式和现浇地铁车站结构地震响应对比研究

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JGG in 2022:challenges,opportunities,and prospects

工程力学 2025年第1期42卷 164-173页

作者：江志伟杨秀仁李霞城市轨道交通绿色与安全建造技术国家工程研究中心北京100037 北京城建设计发展集团股份有限公司北京100037

以往的地下结构抗震研究大多是针对现浇结构开展的，而装配式结构由独立的预制构件拼装而成，从根本上区别于传统整体现浇结构，已有研究得到的认识对其适用性尚不明确，这极大地限制了装配式地下结构在强震区的推广与应用。该文以实际... 详细信息

以往的地下结构抗震研究大多是针对现浇结构开展的，而装配式结构由独立的预制构件拼装而成，从根本上区别于传统整体现浇结构，已有研究得到的认识对其适用性尚不明确，这极大地限制了装配式地下结构在强震区的推广与应用。该文以实际工程为背景，开展了全装配式和同型现浇车站结构的三维非线性有限元时程分析，对比了结构在八度区设防、罕遇和极罕遇地震下的变形、内力和损伤等响应。结果表明：装配式和现浇车站结构整体的地震变形差异不大，但柔性装配式车站结构榫槽节点可产生张开变形。设防和罕遇地震下，节点张开有利于结构减震，装配式车站结构的损伤小于现浇结构;而在极罕遇地震下，节点张开变大，榫槽、榫头和构件边缘的部分区域损伤集中，装配式和现浇结构地震响应产生了较大差异，但因应变幅值有限且损伤范围较小，此时全装配式与现浇车站结构整体的损伤程度基本相当。

关键词：装配式地铁车站结构地下结构抗震预制装配式地下结构装配式车站结构抗震结构地震损伤

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Journal of Genetics and Genomics 2023年第1期50卷 1-2页

作者： Xiaoxuan Guo xiu-fen Song Jianru Zuo Journal of Genetics and Genomics Institute of Genetics and Developmental BiologyChinese Academy of Sciences&the Genetics Society of ChinaBeijing 100101China

During the past 2022,the Journal of Genetics and Genomics(JGG)has seen a variety of challenges as well as *** the difficult time of the COVID-19 pandemic,we have gone through unforeseen difficulties,including the cancellation of academic conferences,drop in submissions,work from home,and *** all these challenges,however,our authors,readers,reviewers,and editorial members have all supported and witnessed the progress of *** 2022,JGG has published a record number of 136 papers reporting cutting-edge studies covering a range of fields in life ***,we briefly highlight important progresses in 2022 in an editorial view.

关键词： academic spite challenges

PI3K expression and PIK3CA mutations are related to colorectal cancer metastases

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World Journal of Gastroenterology 2012年第28期18卷 3745-3751页

作者： Yu-fen Zhu Bao-Hua Yu Da-li li Hong-lin Ke Xian-Zhi Guo xiu-Ying Xiao Department of Oncology Shanghai Xuhui District Center HospitalShanghai 200031 China Department of Pathology Fudan University Shanghai Cancer Center Shanghai 200032 China

AIM: To assess the significance of phosphatidylinositol 3-kinase (PI3K) in colorectal cancer (CRC) and toxicity of LY294002 in CRC cells with different metastatic abilities. METHODS: Sixty formalin-fixed and paraffin-embedded CRC tumor specimens were investigated. Adjacent normal colonic mucosa specimens from 10 of these cases were selected as controls. PI3K protein was detected by immunohistochemistry and PIK3CA mutations were investigated by gene sequencing analysis. A flowcytometry-based apoptosis detection kit was used to determine PI3K inhibitor-induced apoptosis in CRC cell lines SW480 and SW620. Expression of phosphorylated protein kinase B in CRC cell lines was detected by Western blotting. RESULTS: There was a significant difference in the proportion of primary lesions (30%, 18/60) vs metastatic lesions (46.7%, 28/60) that were positive for PI3K (P A resulting in E545A, and C.3140A>G resulting in H1047R; two novel missense mutations C.1624G>A and C.3079G>A; and three synonymous mutations (C.1641G>A, C.1581C>T and C.3027T>A). Exposure of SW480 cells to PI3K inhibitor for 48 h resulted in a significant increase of apoptotic cells in a dose-dependent manner [3.2% apoptotic cells in 0 μmol/L, 4.3% in 5 μmol/L, 6.3% in 10 μmol/L (P line for 48 h [3.3% apoptotic cells in 0 μmol/L, 13.3% in 5 μmol/L (P < 0.01), 19.2% in 10 μmol/L (P < 0.01), and 21.3% in 20 μmol/L (P < 0.01)]. CONCLUSION: High PI3K expression is associated with CRC metastasis. PI3K inhibitor induced apoptosis in CRC cells and displayed strong cytotoxicity for highly metastatic cells. PI3K inhibition may be an effective treatment for CRC.

关键词： Colorectal cancer PI3K PIK3CA Metastasis

Hydrolysis of Dipeptide Heptyl Esters with Newlase F

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Chinese Chemical Letters 2001年第8期12卷 693-696页

作者： Zhong Zhou CHEN Yan Mei li xiu fen KOU Xue li Fu Rong HUANG Hai Yan WANG Ming Ming MA Yu fen ZHAO Key Laboratory for Bioorganic Phosphorus Chemistry of Education Ministry Department of ChemistrySchool of Life Science and EngineeringTsinghua UniversityBeijing 100084 The Institute of Microbiology Chinese Academy of SciencesBeijing 100080

Newlase F is a rude enzyme which contains triacylglycerol lipase and acid protease. Hydrolysis of dipeptide heptyl esters with Newlase F was studied in phosphate buffer-organic solvent by HPLC. When the Newlase F's level reached 5 mg/mL under mild condition (PH 7.0, 30 degreesC), the lipase had the highest activity. The reaction was also affected greatly by organic solvents and their concentrations. It is found that protease in Newlase F does not hydrolyze amide bond under this condition (pH 7.0, r.t.).

关键词： Newlase F dipeptide heptyl esters HPLC

Effect of Vegetation Changes on Soil Erosion on the Loess Plateau

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Pedosphere 2006年第4期16卷 420-427页

作者： ZHENG fen-li State Key Laboratory of Soil Erosion and Dryland Farming in Loess Plateau Northwest A＆F University Yangling 712100 （China）.

Vegetation is one of the key factors affecting soil erosion on the Loess Plateau. The effects of vegetation destruction and vegetation restoration on soil erosion were quantified using data from long-term field runoff plots established on the eastern slope of the Ziwuling secondary forest region, China and a field survey. The results showed that before the secondary vegetation restoration period (before about 1866-1872), soil erosion in the Ziwuling region of the Loess Plateau was similar to the current erosion conditions in neighboring regions, where the soil erosion rate now is 8000 to 10000 t km-2 year-1. After the secondary vegetation restoration, soil erosion was very low; influences of rainfall and slope gradient on soil erosion were small; the vegetation effect on soil erosion was predominant; shallow gully and gully erosion ceased; and sediment deposition occurred in shallow gully and gully channels. In modern times when human activities destroyed secondary forests, soil erosion increased markedly, and erosion rates in the deforested lands reached 10000 to 24000 t km-2 year-1, which was 797 to 1682 times greater than those in the forested land prior to deforestation. Rainfall intensity and landform greatly affected the soil erosion process after deforestation. These results showed that accelerated erosion caused by vegetation destruction played a key role in soil degradation and eco-environmental deterioration in deforested regions.

关键词： deforestation Loess Plateau natural vegetation restoration soil erosion

SCISSORS DIFFERENCE AND ITS IMPACTS ON ECONOMIC VALUE OF CULTIVATED LAND IN CHINA

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Chinese Geographical Science 2005年第3期15卷 193-199页

作者： WANG xiu-fen CHEN Bai-ming BI Ji-ye Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101 P. R. China Graduate School of Chinese Academy of Sciences Beijing 100039 P. R. China China lnstitute of Land and Surveying Ministry of Land and Resources Beijing 100035 P. R. China

The problem of price scissors difference between industrial products and agricultural products is one of the important problems in China. It impacts not only the living standard improvement of farmers but also the economic value of cultivated land, furthermore results in the direct and indirect loss of cultivated land resources. China＇s cultivated land area has decreased dramatically in recent years. An important reason for the decrease is the relatively low cost of cultivated land occupancy, which results from the distortion of economic value of cultivated land due to the existence of scissors difference. This study firstly analyzed the dynamic change of scissors difference and calculated the absolute and relative magnitude of scissors difference from 1997 to 2002, then computed the economic value of cultivated land before and after scissors difference adjustment in 2002, and finally discussed the inverted scissors difference. Results suggest that the scissors difference has a remarkable impact on the economic value of cultivated land, and the adjustment of scissors difference even inverted scissors difference to the economic value of cultivated land is indisoensable.

关键词： cultivated land economic value scissors difference scissors difference adjustment P. R. China

Effects of Accelerated Soil Erosion on Soil Nutrient Loss After Deforestation on the Loess Plateau

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Pedosphere 2005年第6期15卷 707-715页

作者： ZHENG fen-li State Key Laboratory of Soil Erosion and Dryland Farming in Loess Plateau Institute of Soil and Water ConservationChinese Academy of Sciences and Ministry of Water Resources Yangling 712100 （China）

Soil erosion and nutrient losses on newly-deforested lands in the Ziwuling Region on the Loess Plateau of China were monitored to quantitatively evaluate the effects of accelerated soil erosion, caused by deforestation, on organic matter, nitrogen and phosphorus losses. Eight natural runoff plots were established on the loessial hill slopes representing different erosion patterns of dominant erosion processes including sheet, rill and shallow gully (similar to ephemeral gully). Sediment samples were collected after each erosive rainfall event. Results showed that soil nutrients losses increased with an increase of erosion intensity. linear relations between the losses of organic matter, total N, NH4-N, and available P and erosion intensity were found. Nutrient content per unit amount of eroded sediment decreased from the sheet to the shallow gully erosion zones, whereas total nutrient loss increased. Compared with topsoil, nutrients in eroded sediment were enriched, especially available P and NH4-N. The intensity of soil nutrient losses was also closely related to soil erosion intensity and pattern with the most severe soil erosion and nutrient loss occurring in the shallow gully channels on loessial hill slopes. These research findings will help to improve the understanding of the relation between accelerated erosion process after deforestation and soil quality degradation and to design better eco-environmental rehabilitation schemes for the Loess Plateau.

关键词： accelerated soil erosion deforestation erosion intensity Loess Plateau nutrient loss

Effect of CXCR4 pretreated with ultrasound-exposed microbubbles on accelerating homing of bone marrow mesenchymal stem cells to ischemic myocardium in AMI rats

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Asian Pacific Journal of Tropical Medicine 2015年第9期8卷 751-756页

作者： Jun-Yi Gu Hui-fen Shi xiu-li Gao Qing-Qing Ma Bo Zhang Department of Ultrasound in Medicine East Hospital Tongji University School of Medicine

Objective: To investigate the role and potential mechanism of CXCR4 in promoting targeted homing of bone marrow mesenchymal stem cells(BMSCs) with ultrasound-exposed microbubbles(UM) pretreatment. Methods: Third generation BMSCs were divided into four groups control group, ultrasound(US) group, UM group and ultrasound-exposed microbubbles plus catalase group. RT-PCR and western blot were performed to determine the levels of CXCR4 m RNA transcription and protein expression, respectively. Third generation BMSCs were labeled with Fluo-α/AM and divided into three groups: control group, US group and UM group, and flurorescence intensities in the cells were observed immediately, 5 min and 15 min after intervention underflurorescence microscope. The calcium iron levels in the cells were analyzed. BMSCs were divided into i ve group: group A without calcium in the medium, group B, group C, group D and group E containing calcium chloride with concentration of l mol, 2 mol, 4mol, anti-calciurn-sensing receptor antibody, respectively. RT-PCR and western blot were performed to determine the levels of CXCR4 m RNA transcription and proteins expression of the third generation BMSCs of each group, respectively. Results: The levels of CXCR4 m RNA transcription and protein expression between US group and control group had no statistically signii cant dif erence(P>0.05) shown by RT-PCR and western blot; the transcription level in the UM group was signii cantly higher than that in US group and control group(P0.05), which in the cells of UM group was signii cantly higher than that in the cells of both US group and control group(P<0.05). Compared to group A, expressions of CXCR4 of group B to D were signii cantly increased in

关键词： Ultrasound-exposed microbubbles Bone marrow mesenchymal stem cells CXCR4 Calciumion

AN UNSTRUCTURED FINITE-VOLUME ALGORITHM FOR NONliNEAR TWO-DIMENSIOAL SHALLOW WATER EQUATION

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Journal of Hydrodynamics 2005年第3期17卷 306-312页

作者： WANGZhi-li GENGYan-fen JINSheng StateKeyLaboratoryofCoastalandoffshoreEngineering DalianUniversityofTechnologyDalian116024China

An unstructured finite-volume numerical algorithm was presented for solution of the two-dimensional shallow water equations, based on triangular or arbitrary quadrilateral meshes. The Roe type approximate Riemann solver was used to the system. A second-order TVD scheme with the van Leer limiter was used in the space discretization and a two-step Runge-Kutta approach was used in the time discretization. An upwind, as opposed to a pointwise, treatment of the slope source terms was adopted and the semi-implicit treatment was used for the friction source terms. Verification for two-dimension dam-break problems are carried out by comparing the present results with others and very good agreement is shown.

关键词： shallow water equation dam break Riemann solver finite-volume method source terms