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Coseismic Coulomb stress changes induced by a 2020-2021 M_(W)>7.0 Alaska earthquake sequence in and around the Shumagin gap and its influence on the Alaska-Aleutian subduction interface
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作者 Lei Yang Jianjun Wang Caijun Xu 《Geodesy and Geodynamics》 EI CSCD 2024年第1期1-12,共12页
Three M_(W)>7.0 earthquakes in 2020-2021 occurred in the Shumagin seismic gap and its adjacent area of the Alaska-Aleutian subduction zone,including the Mw7.8 Simeonof thrust earthquake on July 22,2020,the M_(W)7.6... Three M_(W)>7.0 earthquakes in 2020-2021 occurred in the Shumagin seismic gap and its adjacent area of the Alaska-Aleutian subduction zone,including the Mw7.8 Simeonof thrust earthquake on July 22,2020,the M_(W)7.6 Sand Point strike-slip earthquake on October 19,2020,and the M_(W)8.2 Chignik thrust earthquake on July 29,2021.The spatial and temporal proximity of these three earthquakes prompts us to probe stress-triggering effects among them.Here we examine the coseismic Coulomb stress change imparted by the three earthquakes and their influence on the subduction interface.Our results show that:(1)The Simeonof earthquake has strong loading effects on the subsequent Sand Point and Chignik earthquakes,with the Coulomb stress changes of 3.95 bars and 2.89 bars,respectively.The Coulomb stress change caused by the Sand Point earthquake at the hypocenter of the Chignik earthquake is merely around 0.01 bars,suggesting the negligible triggering effect on the latter earthquake;(2)The triggering effects of the Simeonof,Sand Point,and Chignik earthquakes on aftershocks within three months are not well pronounced because of the triggering rates of 38%,14%,and 43%respectively.Other factors may have played an important role in promoting the occurrence of these aftershocks,such as the roughness of the subduction interface,the complicated velocity structure of the lithosphere,and the heterogeneous prestress therein;(3)The three earthquakes caused remarkable coseismic Coulomb stress changes at the subduction interface nearby these mainshocks,with an average Coulomb stress change of 3.2 bars in the shallow region directly inwards the trench. 展开更多
关键词 The 2020-2021 Alaska earthquake SEQUENCE Coseismic Coulomb stress change Mainshock-aftershock triggering The Alaska-Aleutian subduction interface The Shumagin gap
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Ghrelin regulates insulin resistance by targeting insulin-like growth factor-1 receptor via miR-455-5p in hepatic cells
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作者 GUO Zhan-hong JU Yue-jun +4 位作者 SHEN Ting ZHANG Lin-qi SHENG Zhong-qi WU Run-ze KONG Ying-hong 《Journal of Hainan Medical University》 CAS 2024年第1期22-28,共7页
Objective: To explore the mechanism by which ghrelin regulates insulin sensitivity through modulation of miR-455-5p in hepatic cells. Methods: HepG2 cells were treated with or without DAG (1 μM). Glucose consumption,... Objective: To explore the mechanism by which ghrelin regulates insulin sensitivity through modulation of miR-455-5p in hepatic cells. Methods: HepG2 cells were treated with or without DAG (1 μM). Glucose consumption, intracellular glycogen content, phosphorylation of PI3K and Akt stimulated by insulin, expression of miR-455-5p, as well as IGF-1R protein level were analyzed. In addition, bioinformatic analysis, dual luciferase reporter assay, miR- 455-5p mimic or inhibitor treatment was conducted to investigate the molecular mechanisms. Results: High glucose treatment upregulated miR-455-5p expression but reduced glucose consumption and glycogen content. DAG reversed the effect of high glucose on glucose metabolism, increased protein level of IGF-1R and phosphorylation of PI3K/Akt stimulated by insulin, as well as downregulated miR-455-5p expression. Bioinformatic analysis indicated IGF-1R was the target of miR-455-5p. Dual luciferase reporter assay, as well as transfection with miR-455-5p mimic/inhibitor confirmed that DAG activated IGF-1R/PI3K/Akt signaling via inhibiting miR-455-5p. Conclusion: DAG improves insulin resistance via miR-455-5p- mediated activation of IGF-1R/PI3K/Akt system, suggesting that suppression of miR-455-5p or activation of DAG may be potential targets for T2DM therapy. 展开更多
关键词 GHRELIN miR-455-5p IGF-1R Insulin resistance HepG2 cells
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Identification and Evaluation of Insect and Disease Resistance in Transgenic Cry1Ab13-1 and NPR1 Maize
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作者 Yongjing Xi Zhou Yang +4 位作者 Yukun Jin Jing Qu Shuyan Guan Siyan Liu Piwu Wang 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第4期1257-1274,共18页
PCR detection,quantitative real-time PCR(q-RTPCR),outdoor insect resistance,and disease resistance identification were carried out for the detection of genetic stability and disease resistance through generations(T2,T... PCR detection,quantitative real-time PCR(q-RTPCR),outdoor insect resistance,and disease resistance identification were carried out for the detection of genetic stability and disease resistance through generations(T2,T3,and T4)in transgenic maize germplasms(S3002 and 349)containing the bivalent genes(insect resistance gene Cry1Ab13-1 and disease resistance gene NPR1)and their corresponding wild type.Results indicated that the target genes Cry1Ab13-1 and NPR1 were successfully transferred into both germplasms through tested generations;q-PCR confirmed the expression of Cry1Ab13-1 and NPR1 genes in roots,stems,and leaves of tested maize plants.In addition,S3002 and 349 bivalent gene-transformed lines exhibited resistance to large leaf spots and corn borer in the field evaluation compared to the wild type.Our study confirmed that Cry1Ab13-1 and NPR1 bivalent genes enhanced the resistance against maize borer and large leaf spot disease and can stably inherit.These findings could be exploited for improving other cultivated maize varieties. 展开更多
关键词 MAIZE NPR1 gene Cry1Ab13-1 gene disease resistance insect resistance
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Research on geo-electrical resistivity observation system specially used for earthquake monitoring in China 被引量:7
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作者 Jialiu Zhao Lanwei Wang Jiadong Qian 《Earthquake Science》 CSCD 2011年第6期497-511,共15页
This paper deals with the design and development of the observational system of geo-electrical resistivity on the basis of the demands for exploring the temporal variations of electrical properties of Earth media in t... This paper deals with the design and development of the observational system of geo-electrical resistivity on the basis of the demands for exploring the temporal variations of electrical properties of Earth media in the fixed points of the networks, which would be associated with the earthquake preparation. The observation system is characterized by the high accuracy in measurement, long term stability in operation and high level of rejection to the environmental interference. It consists of three main parts, configuration system measurement system, the calibration and inspection system. 展开更多
关键词 geo-electrical resistivity observation system earthquake monitoring configuration system measurement system calibration and inspection system
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Relationship Between Serum microRNA-372-3p and Glucose Transporter 4 Levels and Insulin Resistance in Gestational Diabetes Mellitus
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作者 Jinjin Qin Chenyuan Cao +3 位作者 Yakun Zhao Jing Wang Hongli Wu Bei Wang 《Proceedings of Anticancer Research》 2023年第2期12-17,共6页
Objective:To observe the changes in insulin resistance in patients with gestational diabetes mellitus(GDM)based on the detection of serum microRNA-372-3p and glucose transporter protein 4(GLUT4)levels.Methods:We condu... Objective:To observe the changes in insulin resistance in patients with gestational diabetes mellitus(GDM)based on the detection of serum microRNA-372-3p and glucose transporter protein 4(GLUT4)levels.Methods:We conducted a retrospective cohort study of 42 patients who were diagnosed with GDM and hospitalized in our hospital during the period from January 2017 to December 2021 and another 42 patients who had normal pregnancy during the same period by collecting their clinical data.We analyzed their serum microRNA expression profiles and miR-372-3p levels to study the relationship between GDM and insulin resistance.Results:The relative expression of miR-372-3p in the serum of patients in the GDM group was significantly higher than that of patients in the control group,but the GLUT 4 level of the GDM group was significantly lower than that of the control group(P<0.05).Compared with the control group,the GDM group had significantly higher levels of fasting blood glucose(FBG),fasting insulin(FINS),2-hour postprandial blood glucose(2h-BG),total cholesterol(TC),triglyceride(TG),and homeostatic model assessment for insulin resistance(HOMA-IR)index but significantly lower homeostasis model assessment ofβ-cell function(HOMA-β)index(P<0.05).The relative expression of miR-372-3p in serum was independently and positively correlated with HOMA-IR,while the level of GLUT4 was independently and negatively correlated with HOMA-IR(P<0.05).Conclusion:Glycosylated hemoglobin test in the early stages of pregnancy(12–13 weeks of gestation)is important to ensure the health of pregnant women and fetuses.The screening and intervention for elevated glucose in pregnant women act as a guideline for the treatment of GDM.Patients with insulin resistance and related complications such as hyperinsulinemia and hypoglycemia should be given priority. 展开更多
关键词 Gestational diabetes mellitus microRNA-372-3p Glucose transporter Insulin resistance
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Earthquake-resistant performance investigation for rural buildings in Zhongxiang area, China
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作者 Lei Jingya Wang Lei +2 位作者 Wang Kailing Gong Kaihong Hu Jian 《Geodesy and Geodynamics》 2013年第1期55-60,共6页
We carried out a census of the rural residential buildings of Zhongxiang area' s 17 towns. Next, we conducted a sample survey in four townships: Huji, Shipai, Zhangji, and Jiuli. According to the census and sample s... We carried out a census of the rural residential buildings of Zhongxiang area' s 17 towns. Next, we conducted a sample survey in four townships: Huji, Shipai, Zhangji, and Jiuli. According to the census and sample survey data of the rural residence buildings, we evaluated the quality and earthquake-resistant performance of the rural buildings for the various local rural residential structural types. The results showed that there are four main factors affecting the seismic performance of the local rural residences : ( 1 ) Foundations are not made appropriately ( such as by compaction or some other fill) but are built directly in the farming soil. (2) Seismic measures are not completely implemented. Structure construction measures are not in place at the junction of the vertical and horizontal wall. The vertical wall joints are not the result of the same masonry techniques as the horizontal joints. There are no lintels above the door and window openings, or if there are any, the length of the lintels is less than 240 mm. (3) The brick masonry wall has low strength. The greatest housing wall mortar strength is between M0. 4 - 1.5, much lower than the strength of the brick. (4) The building material and construction quality are poor. The quality of the mortar masonry wall is poor. The cracks between the bricks are uneven, even in the seams. 展开更多
关键词 rural buildings structure type seismic precaution earthquake-resistant performance estimation earthquake disaster reduction
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隋唐·安得广厦千万间--漫步地震五千年(9)
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作者 冯锐 《地震科学进展》 2024年第7期483-496,共14页
隋唐时期的史载地震主要在关中地区,显现了秦岭南侧存在一条北西向的石泉—房县活动断裂带。地震活动和房屋抗震一直是社会关注的大事,以蓟县独乐寺为典型代表,重点介绍了唐代木结构建筑的抗震技术:地基坚固和均匀、木结构的隔震机制、... 隋唐时期的史载地震主要在关中地区,显现了秦岭南侧存在一条北西向的石泉—房县活动断裂带。地震活动和房屋抗震一直是社会关注的大事,以蓟县独乐寺为典型代表,重点介绍了唐代木结构建筑的抗震技术:地基坚固和均匀、木结构的隔震机制、筒体结构的强抗震性能、斗拱构件的阻尼系统,都对后世的技术发展产生了深刻影响。在现代建筑方面,介绍了地震区划的基本原则,分析了农村藏式民居的弱点和改进措施,讨论了城市建筑的3种抗震结构及今后的发展方向。 展开更多
关键词 抗震建筑 唐代木结构建筑 地震区划 农村的藏式民居 城市的3种抗震结构
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Calculation of the parameters of georesistivi-ty anisotropy and case history of earthquake precursors 被引量:4
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作者 钱复业 赵玉林 黄燕妮 《Acta Seismologica Sinica(English Edition)》 CSCD 1996年第4期82-92,共11页
This paper has discussed the effective resistivity ellipse and the paradoxical phenomenon of anisotropy. Two cases have been discussed, namely: there are three measuring lines at arbitrary angles with one another and... This paper has discussed the effective resistivity ellipse and the paradoxical phenomenon of anisotropy. Two cases have been discussed, namely: there are three measuring lines at arbitrary angles with one another and there are two mutually perpendicular measuring lines and an additional measurement of the transversal effective resistivity. For these cases, the paper has given the methods for quantitatively calculating the parameters of georesistivity anisotropy. The formulae given include those for calculating the azimuth (of the principal axis of minimum resistivity ρ 1, the average resistivity ( ρ 1ρ 3) 1/2 , (ρ 2ρ 3) 1/2 , and the anisotropy coefficient λ=(ρ 2/ρ 1 ) 1/2 . As a case history, the data observed by the Datong geoelectricity station have been processed with reference to the results of in situ resistivity measurement in media subjected to shear. The results of analysis have led to the following understandings. Before and after the Datong M S6.1 earthquake on October 19, 1989, the abnormal rise of NE trending georesistivity and abnormal fall of NW trending georesistivity observed at the Datong and Yangyuan stations were caused by the pure shear acting on the medium. The major principal compression was in NE direction, which made an acute angle with the strike of the seismic fault plane, and thus there was a greater shear stress but very small normal stress so that the fault was likely to slide but the earthquake was only of moderate magnitude. The states of stress in medium were the same before and after earthquake and therefore the georesistivity precursor was of the same sign as that of co seismic variations. 展开更多
关键词 effective resistivity ellipse paradox of anisotropy Datong M S6.1 earthquake geoelectric precursor pure shear.
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The variations of the degree of ground resistivity anisotropy during the Tangshan earthquake 被引量:4
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作者 毛桐恩 王铁成 +2 位作者 姚家福 卢军 张洪魁 《Acta Seismologica Sinica(English Edition)》 CSCD 1995年第4期621-627,共7页
Based on the geoelectric observation data of the 1976 Tangshan earthquake of M=7. 8 compiled by the Research Group on the Geoelectricity of the Tangshan Great Earthquake, a dimensionless factor S has been defined as t... Based on the geoelectric observation data of the 1976 Tangshan earthquake of M=7. 8 compiled by the Research Group on the Geoelectricity of the Tangshan Great Earthquake, a dimensionless factor S has been defined as the degree of ground resistivity anisotropy. The S values during the generation process of that earthquake have been calculated and their variations have been analyzed. The result has showed that the variation of the degree of ground resistivity anisotropy existed throughout the process of generation and occurrence of the Tangshan earthquake and the features of its pattern are representative. The S value can therefore be taken as a new precursory factor of earthquakes which can be applied together with other dimensionless factors in the analysis and prediction of earthquakes. A physical explanation of the variation of the S value has also been given. 展开更多
关键词 Tangshan earthquake ground resistivity anisotropy
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Fault plane parameters of Sanhe-Pinggu M8 earthquake in 1679 determined using present-day small earthquakes 被引量:10
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作者 Xiaoshan Wang Xiangdong Feng +4 位作者 Xiwei Xu Guiling Diao Yongge Wan Libin Wang Guangqing Ma 《Earthquake Science》 2014年第6期607-614,共8页
The great Sanhe-Pinggu M8 earthquake occurred in 1679 was the largest surface rupture event recorded in history in the northern part of North China plain. This study determines the fault geometry of this earthquake by... The great Sanhe-Pinggu M8 earthquake occurred in 1679 was the largest surface rupture event recorded in history in the northern part of North China plain. This study determines the fault geometry of this earthquake by inverting seismological data of present-day moderate-small earthquakes in the focal area. We relocated those earthquakes with the double-difference method. Based on the assumption that clustered small earthquakes often occur in the vicinity of fault plane of large earthquake, and referring to the morphology of the long axis of the isoseismal line obtained by the predecessors, we selected a strip-shaped zone from the relocated earthquake catalog in the period from 1980 to 2009 to invert fault plane parameters of this earthquake. The inversion results are as follows: the strike is 38.23°, the dip angle is 82.54°, the slip angle is -156.08°, the fault length is about 80 km, the lower-boundary depth is about 23 km and the buried depth of upper boundary is about 3 kin. This shows that the seismogenic fault is a NNE-trending normal dip-slip fault, southeast wall downward and northwest wall uplift, with the right-lateral strike-slip component. Moreover, the surface rupture zone, intensity distribution of the earth-quake and seismic-wave velocity profile in the focal area all verified our study result. 展开更多
关键词 Sanhe-Pinggu M8 earthquake Present-daymoderate-small earthquakes - Double-differenceearthquake location - Tectonic stress field Fault planeparameter
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The pattern characteristics of the tendency variations of earth resistivity and its relation to earthquakes 被引量:1
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作者 赵和云 《Acta Seismologica Sinica(English Edition)》 CSCD 1994年第3期465-474,共10页
Through systematically summarizing the observational data of earth resistivity during 26 years from nearly a hundred stations in China, the author found that the pattern of the earth resistivity (ρs) tendency variati... Through systematically summarizing the observational data of earth resistivity during 26 years from nearly a hundred stations in China, the author found that the pattern of the earth resistivity (ρs) tendency variations,based on monthly average data, could be divided into five types, three types of which were defined as anomalous variation, which have different qualitative and quantitative characteristics and different relations with earthquakes as well.The first type of tendency variation called “funnel” is related to strong earthquakes, the Second type called “scoop” has good corresponding relation with moderate earthquakes, and the third type called “tilt” has no relation with earthquakes. Preliminary discussions about the relations between the three types of ρs tendency variation patterns and earthquakes are made in this paper, according to the experimental results of pressed rocks. It is concluded that the different patterns of ρs tendency variation actually reflect the different stress conditions of underground soil-rock layers: the “funnel” type reflects high stress status, the “scoop” type shows moderate stress condition and the “tilt” type is related to stress relief. All of such knowledges mentioned above are very useful in making accurate medium-term earthquake prediction. 展开更多
关键词 earth resistivity tendency variation classification of pattern earthquake
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Activity of the Fungicide JS399-19 Against Fusarium Head Blight of Wheat and the Risk of Resistance 被引量:7
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作者 CHEN Yu WANG Wen-xiang +3 位作者 ZHANG Ai-fang GU Chun-yan ZHOU Ming-guo GAO Tong-chun 《Agricultural Sciences in China》 CAS CSCD 2011年第12期1906-1913,共8页
This report reviews the characteristics of JS399-19, a novel cyanoacrylate fungicide. JS399-19 strongly inhibits the mycelial growth of the fungal plant pathogens of the genus Fusarium and exhibits great potential in ... This report reviews the characteristics of JS399-19, a novel cyanoacrylate fungicide. JS399-19 strongly inhibits the mycelial growth of the fungal plant pathogens of the genus Fusarium and exhibits great potential in controlling Fusarium head blight (FHB) on wheat and other cereals. The mode of action of JS399-19 is evidently different from that of benzimidazole (for example, carbendazim) and other sort of fungicides, making it a possible replacement for carbendazim in China to manage carbendazim-resistant subpopulations of Fusarium graminearum and F. asiaticum. JS399-t9 has excellent protective and curative activity against these pathogens. Incorrect use of this fungicide, however, is likely to select for resistance. Among JS399-19-resistant mutants of F. asiaticum induced in the laboratory, the resistant level of mutants was high and the phenotype of resistance against JS399-19 was conferred by a major gene by genetic analysis. The fitness of laboratory-induced JS399-19-resistant mutants of F. asiaticum was nearly equal to that of their parents. JS399-19 lacks cross resistance with other sort fungicides. To control FHB with JS399-19 and to delay the development of the fungicide-resistance, farmers should use tank mixtures containing JS399-19 and carbendazim, metconazole, tebuconazole, or prothioconazole. 展开更多
关键词 fungicide JS399-19 cyanoacrylate fungicide Fusarium head blight ACTIVITY resistance risk
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Identification of candidate genes for aphid resistance in upland cotton by QTL mapping and expression analysis
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作者 Qiushuang An Zhenyuan Pan +4 位作者 Nurimanguli Aini Peng Han Yuanlong Wu Chunyuan You Xinhui Nie 《The Crop Journal》 SCIE CSCD 2023年第5期1600-1604,共5页
Lignin is one of the main components of cell walls and is essential for resistance to insect pests in plants.Cotton plants are damaged by aphid(Aphis gossypii) worldwide but resistant breeding is undeveloped due to sc... Lignin is one of the main components of cell walls and is essential for resistance to insect pests in plants.Cotton plants are damaged by aphid(Aphis gossypii) worldwide but resistant breeding is undeveloped due to scarce knowledge on resistance genes and the mechanism. This study reported a lignin biosynthesisrelated gene identified in the F_(2) population derived from the cross between cotton cultivars Xinluzao 61(resistant to aphid) and Xinluzao 50(susceptible to aphid). A quantitative trait locus was mapped on chromosome D04 with a logarithm of odds(LOD) score of 5.99 and phenotypic effect of 27%. RNA-seq analysis of candidate intervals showed that the expression level of GH_D04G1418 was higher in the resistant cultivar than in the susceptible cultivar. This locus is close to AtLAC4 in the phylogenetic tree and contains a conserved laccase domain. Hence, it was designated GhLAC4-3. Silencing of GhLAC4-3 in Xinluzao 61 via virus-induced gene silencing(VIGS) resulted in decreased lignin content and increased susceptibility to aphids. These results suggest that GhLAC4-3 might enhance aphid resistance by regulating lignin biosynthesis in cotton. 展开更多
关键词 GhLAC4-3 LIGNIN Gossypium hirsutum Aphid resistance
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Internal structures and high-velocity frictional properties of Longmenshan fault zone at Shenxigou activated during the 2008 Wenchuan earthquake 被引量:3
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作者 Yu Wang Shengli Ma +7 位作者 Toshihiko Shimamoto Lu Yao Jianye Chen Xiaosong Yang Honglin He Jiaxiang Dang Linfeng Hou Tetsuhiro Togo 《Earthquake Science》 2014年第5期499-528,共30页
This paper reports internal structures of a wide fault zone at Shenxigou,Dujiangyan,Sichuan province,China,and high-velocity frictional properties of the fault gouge collected near the coseismic slip zone during the 2... This paper reports internal structures of a wide fault zone at Shenxigou,Dujiangyan,Sichuan province,China,and high-velocity frictional properties of the fault gouge collected near the coseismic slip zone during the 2008 Wenchuan earthquake.Vertical offset and horizontal displacement at the trench site were 2.8 m(NW side up)and 4.8 m(right-lateral),respectively.The fault zone formed in Triassic sandstone,siltstone,and shale about 500 m away from the Yingxiu-Beichuan fault,a major fault in the Longmenshan fault system.A trench survey across the coseismic fault,and observations of outcrops and drill cores down to a depth of 57 m revealed that the fault zone consists of fault gouge and fault breccia of about0.5 and 250-300 m in widths,respectively,and that the fault strikes N62°E and dips 68° to NW.Quaternary conglomerates were recovered beneath the fault in the drilling,so that the fault moved at least 55 m along the coseismic slip zone,experiencing about 18 events of similar sizes.The fault core is composed of grayish gouge(GG) and blackish gouge(BG) with very complex slip-zone structures.BG contains low-crystalline graphite of about 30 %.High-velocity friction experiments were conducted at normal stresses of 0.6-2.1 MPa and slip rates of 0.1-2.1 m/s.Both GG and BG exhibit dramatic slip weakening at constant high slip rates that can be described as an exponential decay from peak friction coefficient lpto steadystate friction coefficient lssover a slip-weakening distance Dc.Deformation of GG and BG is characterized by overlapped slip-zone structures and development of sharp slickenside surfaces,respectively.Comparison of our data with those reported for other outcrops indicates that the high-velocity frictional properties of the Longmenshan fault zones are quite uniform and the high-velocity weakening must have promoted dynamic rupture propagation during the Wenchuan earthquake. 展开更多
关键词 Wenchuan earthquake - Longmenshan faultsystem - Shenxigou fault zone Fault zone structures High-velocity friction
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Influence of rare earth elements on corrosion resistance of BFe10-1-1 alloys in flowing marine water 被引量:1
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作者 林高用 杨伟 +3 位作者 万迎春 唐鹏钧 魏笔 张胜华 《Journal of Rare Earths》 SCIE EI CAS CSCD 2009年第2期259-263,共5页
The corrosion behavior of BFe10-1-1 alloy with different rare earth (RE) contents in simulated flowing marine water was investigated by X-ray diffractometer and scanning electron microscope (SEM). It was demonstra... The corrosion behavior of BFe10-1-1 alloy with different rare earth (RE) contents in simulated flowing marine water was investigated by X-ray diffractometer and scanning electron microscope (SEM). It was demonstrated that the corrosion rate of BFel0-1-1 alloy with the same chemical compositions in faster flow velocity of marine water was higher than that in a lower flow velocity of marine water. Fixing the flow velocity, BFe 10-1-1 alloy had the best flushing corrosion resistance when the RE content was 0.04wt.%. The consequence of such good corrosion resistance was attributed to the formation of compact protective film on alloy surface containing RE phase such as CeNis. The RE-contained film combines with other corrosion products firmly, which was difficult to fall off from the alloy surface in the flowing marine water. Additionally, SEM analysis confirmed that pitting mechanism, which would be transformed to spalling mechanism gradually with further increasing RE content, was the prevalent mechanism when the alloy contained 0.04wt.%RE. 展开更多
关键词 rare earths BFe10-1-1 alloy corrosion resistance PITTING
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Characterization and functional analysis of β-1,3-galactosyltransferase involved in Cry1Ac resistance from Helicoverpa armigera(Hübner) 被引量:1
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作者 ZHANG Li-li LIANG Ge-mei +2 位作者 GAO Xi-wu CAO Guang-chun GUO Yu-yuan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第2期337-346,共10页
Carbohydrate chains are the principal antigens by which Bacillus thuringiensis(Bt) identify receptor proteins. The interaction between the antigen and Bt causes a pore in the membrane of midgut epithelial cells of i... Carbohydrate chains are the principal antigens by which Bacillus thuringiensis(Bt) identify receptor proteins. The interaction between the antigen and Bt causes a pore in the membrane of midgut epithelial cells of insects. Receptor proteins, such as aminopeptidase N and alkaline phosphatase, are glycoproteins. Cadherin is another cell surface receptor protein which has potential glycosylation sites. Glycosyltransferase is very important for the synthesis and modification of receptor proteins. It can indirectly influence the function of Bt. The 1 950 bp full-length c DNA encoding β-1,3-galactosyltransferase was cloned from the the midgut of Helicoverpa armigera by degenerative PCR combined with RACE techniques(GAL-Harm, Gen Bank accession no.: GQ904195.1) with two potential N-glycosylation sites(^157NNTI^160 and ^272NKTL^275). Protein sequence alignments revealed that H. armigera β-1,3-galactosyltransferase shared high identity with β-1,3-galactosyltransferase in other insect species. The expression level of the β-1,3-galactosyltransferase gene in Cry1Ac-resistant H. armigera larvae was 9.2-fold higher than that in susceptible strain. The function of β-1,3-galactosyltransferase was investigated using RNAi technique. The result showed Cry1 Ac enhanced the toxicity against the si RNA-treated larvae compared with non-si RNA-treated ones, which indicated β-1,3-galactosyltransferase played an important role for the insecticidal toxicity of Cry1 Ac in H. armigera. 展开更多
关键词 β-1 3-galactosyltransferase CRY1AC resistance Helicoverpa armigera RNAI
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Effect of Fused MgO-ZrO_2 Clinker Addition on Thermal Shock Resistance of MgO-ZrO_2 Unfired Bricks 被引量:1
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作者 LI Jiwei ZHOU Ningsheng BAI Hongyu 《China's Refractories》 CAS 2008年第4期11-15,共5页
MgO -ZrO2 unfired bricks with ZrO2 content up to 8% at the interval of 2% were prepared, using fused magnesia ( MgO : 97% ) and fused MgO - ZrO2 clinker ( ZrO2 : 14. 33% ) as starting materials and phenolic resi... MgO -ZrO2 unfired bricks with ZrO2 content up to 8% at the interval of 2% were prepared, using fused magnesia ( MgO : 97% ) and fused MgO - ZrO2 clinker ( ZrO2 : 14. 33% ) as starting materials and phenolic resin as binder. The effects of ZrO2 content on thermal shock resistance (TSR) and other properties such as cold and hot modulus of rupture have been investigated. Re- sidual cold modulus of rupture ratio after heating at 1 000 ℃ and quenching by air blowing was adopted to characterize TSR. Addition of the MgO -ZrO2 clinker improves TSR, attributing to the microcrack toughening effect by thermal expansion mismatch between different phases. When ZrO2 content goes above 4%. the impro- ving effect tends to be moderate. The introduction of MgO- ZrO2 clinker can also improve the HMOR at 1 500 ℃, while the increased ZrO2 content reduces CMOR of the bricks prefired at 1 600 ℃, due to the thermal expansion mismatch effect. Compromising the overall properties, the optimal ZrO2 content for such magnesia based unfired brick is suggested to be 4%. 展开更多
关键词 Magnesia - zirconia system Unfired brick Thermal shock resistance Magnesia-zirconia clinker
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Structure of Micro-nano WC-10Co4Cr Coating and Cavitation Erosion Resistance in NaCl Solution 被引量:1
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作者 Xiang Ding Xu-Dong Cheng +2 位作者 Cheng-Qing Yuan Jin Shi Zhang-Xiong Ding 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第5期1239-1247,共9页
Cavitation erosion (CE) is the predominant cause for the failure of overflow components in fluid machinery. Advanced coatings have provided an effective solution to cavitation erosion due to the rapid development of... Cavitation erosion (CE) is the predominant cause for the failure of overflow components in fluid machinery. Advanced coatings have provided an effective solution to cavitation erosion due to the rapid development of surface engineering techniques. However, the influence of coating structures on CE resistance has not been sys- tematically studied. To better understand their relationship, micro-nano and conventional WC-10Co4Cr cermet coat- ings are deposited by high velocity oxygen fuel spray- ing(HVOF), and their microstructures are analyzed by OM, SEM and XRD. Meanwhile, characterizations of mechan- ical and electrochemical properties of the coatings are carried out, as well as the coatings' resistance to CE in 3.5 wt % NaC1 solution, and the cavitation mechanisms are explored. Results show that micro-nano WC-10Co4Cr coating possesses dense microstructure, excellent mechanical and electrochemical properties, with very low porosity of 0.26 4-0.07% and extraordinary fracture toughness of 5.58 4-0.51 MPa.m1/2. Moreover, the CE resistance of micro-nano coating is enhanced above 50% than conventional coating at the steady CE period in 3.5 wt % NaC1 solution. The superior CE resistance of micro- nano WC-10Co4Cr coating may originate from the unique micro-nano structure and properties, which can effectively obstruct the formation and propagation of CE crack. Thus,a new method is proposed to enhance the CE resistance of WC-10Co4Cr coating by manipulating the microstructure. 展开更多
关键词 Cavitation erosion resistance Micro-nanostructure - WC- 10Co4Cr coating HVOF
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Antimicrobial Resistance,Virulence Profile,and Molecular Characterization of Listeria monocytogenes Isolated from Ready-to-eat Food in China,2013-2014 被引量:3
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作者 YAN Shao Fei WANG Wei +4 位作者 BAI Li HU Yu Jie DONG Yin Ping XU Jin LI Feng Qin 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2016年第6期448-452,共5页
We aimed to investigate the potential pathogenic profile and antibiotic resistance of Listeria monocytogenes isolated from ready-to-eat food in China.Antimicrobial resistance was determined by broth microdilution foll... We aimed to investigate the potential pathogenic profile and antibiotic resistance of Listeria monocytogenes isolated from ready-to-eat food in China.Antimicrobial resistance was determined by broth microdilution following the Clinical and Laboratory Standards Institute protocol Molecular serotyping,virulence,and resistance genes were identified using PCR.Multi-locus 展开更多
关键词 MLST gene Antimicrobial resistance Virulence Profile and Molecular Characterization of Listeria monocytogenes Isolated from Ready-to-eat Food in China 2013-2014 SMZ CLSI
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Magnetotelluric Constraints on the Occurrence of Lower Crustal Earthquakes in the Intra-plate Setting of Central Indian Tectonic Zone
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作者 K.K.ABDUL AZEEZ 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第3期884-899,共16页
Lower crustal earthquake occurrence in the Central Indian Tectonic Zone (CITZ) of the Indian sub-continent was investigated using magnetotelluric (MT) data. MT models across the CITZ, including the new resistivity... Lower crustal earthquake occurrence in the Central Indian Tectonic Zone (CITZ) of the Indian sub-continent was investigated using magnetotelluric (MT) data. MT models across the CITZ, including the new resistivity model across the 1938 Satpura lower crustal earthquake epicenter, show low resistive (〈80 Ωm) mid-lower crust and infer small volume (〈1 vol%) of aqueous fluids existing in most part of lower crust. This in conjunction with xenoliths and other geophysical data supports a predominant brittle/semi-brittle lower crustal theology. However, the local deep crustal zones with higher fluid content of 2.2%-6.5% which have been mapped imply high pore pressure conditions. The observation above and the significant strain rate in the region provide favorable conditions (strong/ moderate rock strength, moderate temperature, high pore pressure and high strain rate) for brittle failure in the lower crust. It can be inferred that the fluid-rich pockets in the mid-lower crust might have catalyzed earthquake generation by acting as the source of local stress (fluid pressure), which together with the regional stress produced critical seismogenic stress conditions. Alternatively, fluids reduce the shear strength of the rocks to favor tectonic stress concentration that can be transferred to seismogenic faults to trigger earthquakes. 展开更多
关键词 resistivity fluids lower crustal earthquake intra-plate Central Indian Tectonic Zone
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