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Morphotectonic Analyses of LiDAR-Derived DEMs:Insights into Tectonic Activity of the Xinhua Fault within the Three Gorges Area(Central China)
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作者 Xiaofeng Wang Xiaohan Yin +4 位作者 Tonghui Liu Xuan Li Hongming Wang Yaqi Zhong Gang Rao 《Journal of Earth Science》 2025年第2期823-829,共7页
0 INTRODUCTION.The global availability of digital elevation model(DEM)data,such as 90-m Shuttle Radar Topography Mission(SRTM)DEM and 30-m Advanced Spaceborne Thermal Emission and Reflection Radiometer Global Digital ... 0 INTRODUCTION.The global availability of digital elevation model(DEM)data,such as 90-m Shuttle Radar Topography Mission(SRTM)DEM and 30-m Advanced Spaceborne Thermal Emission and Reflection Radiometer Global Digital Elevation Model(ASTER GDEM),has been extensively utilized in morphotectonic analyses(e.g.,Wang et al.,2024;Cheng et al.,2018;Pérez-Pe?a et al.,2010;El Hamdouni et al.,2008). 展开更多
关键词 xinhua fault morphotectonic analyses egwang three gorges area digital elevation model aster lidar derived dems tectonic activity morphotectonic analyses digital elevation model dem datasuch
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Profiling and bioinformatics analyses of circular RNAs in myocardial ischemia/reperfusion injury model in mice
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作者 Jiao-Ni Wang Ying-Ying Zhou +1 位作者 Yong-Wei Yu Jun Chen 《World Journal of Cardiology》 2025年第1期65-77,共13页
BACKGROUND Myocardial ischemia/reperfusion(I/R)injury,which is associated with high morbidity and mortality,is a main cause of unexpected myocardial injury after acute myocardial infarction.However,the underlying mech... BACKGROUND Myocardial ischemia/reperfusion(I/R)injury,which is associated with high morbidity and mortality,is a main cause of unexpected myocardial injury after acute myocardial infarction.However,the underlying mechanism remains unclear.Circular RNAs(circRNAs),which are formed from protein-coding genes,can sequester microRNAs or proteins,modulate transcription and interfere with splicing.Authoritative studies suggest that circRNAs may play an important role in myocardial I/R injury.AIM To explore the role and mechanism of circRNAs in myocardial I/R injury.METHODS We constructed a myocardial I/R injury model using ligation of the left anterior descending coronary artery,and evaluated the success of the validated model using triphenyltetrazolium chloride and hematoxylin-eosin staining.Then,left ventricular samples from different groups were selected for mRNA-sequence,and differential gene screening was performed on the obtained results.The differentially obtained mRNAs were divided into up-regulated and down-regulated according to their expression levels,and Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)functional enrichment analysis were performed,respectively.Then,the obtained circRNA and microRNA(miRNA)were paired for analysis,and the binding sites of miRNA and mRNA were virtual screened.Finally,the obtained circRNA,miRNA and mRNA were constructed by ceRNA mutual most useful network.RESULTS We used an RNA sequencing array to investigate the expression signatures of circRNAs in myocardial I/R injury using three samples from the I/R group and three samples from the sham group.A total of 142 upregulated and 121 downregulated circRNAs were found to be differentially expressed(fold change≥2,P<0.05).GO and KEGG functional analyses of these circRNAs were performed.GO analysis revealed that these circRNAs were involved mainly in cellular and intracellular processes.KEGG analysis demonstrated that 6 of the top 20 pathways were correlated with cell apoptosis.Furthermore,a circRNA-miRNA coexpression network and ceRNA network based on these genes were constructed,revealing that mmu-circ-0001452,mmu-circ-0001637,and mmu-circ-0000870 might be key regulators of myocardial I/R injury.CONCLUSION This research provides new insights into the mechanism of myocardial I/R,which mmu-circ-0001452,mmu-circ-0001637,and mmu-circ-0000870 are expected to be new therapeutic targets for myocardial I/R injury. 展开更多
关键词 Rna-sequencing Circular RNA MicroRNA CeRNA Myocardial ischemia/reperfusion Bioinformatics analyses
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Association between osteoporosis and rotator cuff tears:evidence from causal inference and colocalization analyses
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作者 Yibin Liu Rong Zhao +7 位作者 Zhiyu Huang Feifei Li Xing Li Kaixin Zhou Kathleen A.Derwin Xiaofei Zheng Hongmin Cai Jinjin Ma 《Bone Research》 2025年第5期1252-1265,共14页
Osteoporosis is a known risk factor for rotator cuff tears(RCTs),but the causal correlation and underlying mechanisms remain unclear.This study aims to evaluate the impact of osteoporosis on RCT risk and investigate t... Osteoporosis is a known risk factor for rotator cuff tears(RCTs),but the causal correlation and underlying mechanisms remain unclear.This study aims to evaluate the impact of osteoporosis on RCT risk and investigate their genetic associations.Using data from the UK Biobank(n=457871),cross-sectional analyses demonstrated that osteoporosis was significantly associated with an increased risk of RCTs(adjusted OR[95%CI]=1.38[1.25–1.52]).A longitudinal analysis of a subset of patients(n=268117)over 11 years revealed that osteoporosis increased the risk of RCTs(adjusted HR[95%CI]=1.56[1.29–1.87]),which is notably varied between sexes in sex-stratified analysis.Causal inference methods,including propensity score matching,inverse probability weighting,causal random forest and survival random forest models further confirmed the causal effect,both from cross-sectional and longitudinal perspectives. 展开更多
关键词 risk factor rotator cuff tears longitudinal analysis causal inference colocalization analyses OSTEOPOROSIS rotator cuff tears rcts genetic associations
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Critical processes controlling the formation of visible gold in the giant Jiaodong gold province:Constraints from microtextural and geochemical analyses by SEM,TOF-SIMS,and LA-(MC)-ICP-MS
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作者 Hong Wang Ting-Guang Lan +6 位作者 Lang-Ye Zhao Hong-Rui Fan Zhan-Ping Li Huan-Long Hu Zi-Qi Xu Hong-Wei Peng Lei Shu 《Acta Geochimica》 2025年第6期1167-1185,共19页
The world-class Jiaodong gold province in the North China Craton hosts over 5000 t of Au resource and is characterized by abundant visible gold mineralization.However,the critical processes controlling the formation o... The world-class Jiaodong gold province in the North China Craton hosts over 5000 t of Au resource and is characterized by abundant visible gold mineralization.However,the critical processes controlling the formation of visible gold in this province remain poorly understood.To solve this problem,integrated microtextural,trace elemental,and sulfur isotopic analyses of pyrite from the high-grade Linglong gold deposit in the Jiaodong gold province were conducted in this study.Two distinct pyrite types were identified within auriferous quartz-sulfide veins:(1)Py1 aggregates in quartz-pyrite veins(hydrothermal stageⅡ),and(2)euhedral to subhedral,coarse-grained Py2 crystals in quartz-polymetallic sulfide veins(hydrothermal stageⅢ).Microtextural and elemental analyses revealed that visible gold predominantly occurs as intergranular particles between primary pyrite crystals within Py1 aggregates.The Py1 exhibits complex microtextures with abundant mineral inclusions of polymetallic sulfides and has low concentrations of Au(median:0.032 ppm)with a narrowδ^(34)S range(4.86‰-6.75‰),indicative of rapid crystallization under unstable,disequilibrium conditions.By contrast,the Py2 is texturally homogeneous and contains higher Au concentrations(median:0.304 ppm)with progressively increasingδ^(34)S values(5.25‰-10.14‰)over time,suggesting slow crystal growth under more stable,near-equilibrium conditions.Based on the microtextural and geochemical information,it is proposed that fluid boiling occurred only during the hydrothermal stage Ⅱ,which resulted in the unstable physicochemical environment and rapid deposition of gold.During the boiling processes,gold colloids likely occurred and promoted the formation of visible gold. 展开更多
关键词 Visible gold deposition PYRITE GEOCHEMISTRY Jiaodong gold province Microtextural analyses
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The nexus between the financial development and CO_(2) emissions:fresh evidence through time–frequency analyses
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作者 Faik Bilgili Erhan Muğaloğlu +3 位作者 Sevda Kuşkaya Javier Cifuentes‑Faura Kamran Khan Mohammed Alnour 《Financial Innovation》 2025年第1期1442-1463,共22页
Climate change and environmental degradation threaten the world and global economic conditions.As one of countries’most important economic components,the financial sector might be an effective tool for reducing and e... Climate change and environmental degradation threaten the world and global economic conditions.As one of countries’most important economic components,the financial sector might be an effective tool for reducing and even reversing environmental degradation.The financial sector can affect sustainability through its lending and investment practices.The sector can play a role in financing sustainable projects and businesses,helping reduce CO_(2) emissions.By aligning its financial objectives with environmental protection,the financial sector can support the transition to a more sustainable future by helping reduce environmental degradation’s negative impacts.This paper examines the domestic financial sector’s impact on CO_(2) emissions in the United States over the 1990:Q1–2022:Q3 period.In this research,the nexus between the domestic financial sector(total debt securities,loans,liabilities,and total financial assets)and Carbon dioxide emissions in the U.S.is investigated by Morlet wavelet analysis.Rest of the world:sector discrepancy transactions,rest of the world:debt securities and loans,gross domestic product,and the square of the gross domestic product,are control variables in the estimated models.Partial wavelet coherency analyses prove that the financial sector reduces CO_(2) emissions at the 5–8-year frequency band during different subsample periods.The financial sector’s instruments can be effective in struggling with climate change. 展开更多
关键词 Financial sector Sustainable development Time-frequency analysis Wavelet analyses The U.S.
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Dynamic Response Analyses and Experimental Research into Deep-Sea Mining Systems Based on Flexible Risers
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作者 Jianyu Xiao Zhuang Kang +3 位作者 Ming Chen Yijun Shen Yanlian Du Jing Leng 《哈尔滨工程大学学报(英文版)》 2025年第4期789-804,共16页
The deep seabed is known for its abundant reserves of various mineral resources.Notably,the Clarion Clipperton(C-C)mining area in the northeast Pacific Ocean,where China holds exploration rights,is particularly rich i... The deep seabed is known for its abundant reserves of various mineral resources.Notably,the Clarion Clipperton(C-C)mining area in the northeast Pacific Ocean,where China holds exploration rights,is particularly rich in deep-sea polymetallic nodules.These nodules,which are nodular and unevenly distributed in seafloor sediments,have significant industrial exploitation value.Over the decades,the deep-sea mining industry has increasingly adopted systems that combine rigid and flexible risers supported by large surface mining vessels.However,current systems face economic and structural stability challenges,hindering the development of deep-sea mining technology.This paper proposes a new structural design for a deep-sea mining system based on flexible risers,validated through numerical simulations and experimental research.The system composition,function and operational characteristics are comprehensively introduced.Detailed calculations determine the production capacity of the deep-sea mining system and the dimensions of the seabed mining subsystem.Finite element numerical simulations analyze the morphological changes of flexible risers and the stress conditions at key connection points under different ocean current incident angles.Experimental research verifies the feasibility of collaborative movement between two tethered underwater devices.The proposed deep-sea mining system,utilizing flexible risers,significantly advances the establishment of a commercial deep-sea mining system.The production calculations and parameter determinations provide essential references for the system’s future detailed design.Furthermore,the finite element simulation model established in this paper provides a research basis,and the method established in this paper offers a foundation for subsequent research under more complex ocean conditions.The control strategy for the collaborative movement between two tethered underwater devices provides an effective solution for deep-sea mining control systems. 展开更多
关键词 Deep-sea mining Flexible riser Underwater mineral resources Dynamic response analyses Collaborative movement
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Dimensional synchronous modeling-based enhanced Kriging algorithm and adaptive Copula method for multi-objective synthetical reliability analyses
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作者 Cheng LU Yunwen FENG +1 位作者 Chengwei FEI Da TENG 《Chinese Journal of Aeronautics》 2025年第9期144-165,共22页
To accomplish the reliability analyses of the correlation of multi-analytical objectives,an innovative framework of Dimensional Synchronous Modeling(DSM)and correlation analysis is developed based on the stepwise mode... To accomplish the reliability analyses of the correlation of multi-analytical objectives,an innovative framework of Dimensional Synchronous Modeling(DSM)and correlation analysis is developed based on the stepwise modeling strategy,cell array operation principle,and Copula theory.Under this framework,we propose a DSM-based Enhanced Kriging(DSMEK)algorithm to synchronously derive the modeling of multi-objective,and explore an adaptive Copula function approach to analyze the correlation among multiple objectives and to assess the synthetical reliability level.In the proposed DSMEK and adaptive Copula methods,the Kriging model is treated as the basis function of DSMEK model,the Multi-Objective Snake Optimizer(MOSO)algorithm is used to search the optimal values of hyperparameters of basis functions,the cell array operation principle is adopted to establish a whole model of multiple objectives,the goodness of fit is utilized to determine the forms of Copula functions,and the determined Copula functions are employed to perform the reliability analyses of the correlation of multi-analytical objectives.Furthermore,three examples,including multi-objective complex function approximation,aeroengine turbine bladeddisc multi-failure mode reliability analyses and aircraft landing gear system brake temperature reliability analyses,are performed to verify the effectiveness of the proposed methods,from the viewpoints of mathematics and engineering.The results show that the DSMEK and adaptive Copula approaches hold obvious advantages in terms of modeling features and simulation performance.The efforts of this work provide a useful way for the modeling of multi-analytical objectives and synthetical reliability analyses of complex structure/system with multi-output responses. 展开更多
关键词 Adaptive Copula method Aeroengine turbine bladeddisc Aircraft landing gear system Correlation of multianalytical objectives Dimensional synchronous modeling-based enhanced Kriging algorithm Reliability analyses
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VALIDATION AND ANALYSES OF THE SIMPLE METHOD FOR DETERMINING rm OF APHIDS AND MITES
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作者 况荣平 R. Fleming 《Zoological Research》 CAS CSCD 1992年第1期37-46,共10页
This paper deals with the validation and theoretical analyses of a simple method for calculating the intrinsic rate of increase, rm, of aphids and mites. This method does not require a detailed fecundity table data. T... This paper deals with the validation and theoretical analyses of a simple method for calculating the intrinsic rate of increase, rm, of aphids and mites. This method does not require a detailed fecundity table data. The value of rm can be estimated by the simple equation: rm=0.74ln (Md)/d, where d is the time from birth to first reproduction; Md is the number of female offspring produced per original female in 2d. This method was developed by Wyatt and White. We reached the following conclusions from our study: When the parameter, Md is less than 1, this equation is not appropriate for estimating rm of populations; When the parameter, Md is larger than 1 and about 70% or more of the reproductive contribution to the rm is achieved in 2d, the equation is appropriate for calculatng the rm of aphids and mites.As Md decreases, the required reproductive contribution to the rm in 2d corresponding to the constant 0.74 will increase. However, whether 70% or more of reproductive contribution to rm is achieved in 2d still is a problem for whole taxa of aphids and mites. Therefore, further siudy on reproductive distribution will be required for practical application of this method. 展开更多
关键词 Intrinsic rate of increase APHIDS MITES Simple calculation VALIDATION analyses
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THREE-DIMENSIONAL STATIC ANALYSES FOR FGM PLATES WITH MEDIUM COMPONENTS AND DIFFERENT NET STRUCTURES
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作者 Hongmei Cheng Zhiyuan Cao 《Acta Mechanica Solida Sinica》 SCIE EI 2010年第2期167-174,共8页
A new microelement method for the analyses of functionally graded structures was proposed. The key of this method is the maneuverable combination of two kinds of elements. Firstly, the macro elements are divided from ... A new microelement method for the analyses of functionally graded structures was proposed. The key of this method is the maneuverable combination of two kinds of elements. Firstly, the macro elements are divided from the functionally graded material structures by the normal finite elements. In order to reflect the functionally graded distributions of materials and the microconstitutions in each macro-element, the microelement method sets up the dense microelements in every macro-element, and translates nodes to the same as the normal finite elements by the degrees of freedom of all microelemental the compatibility conditions. This microelement method can fully reflect the micro constitutions and different components of materials, and its computational elements are the same as the normal finite elements, so it is an effective numerical method for the analyses of the functionally graded material structures. The three-dimensional analyses of functionally graded plates with medium components and different micro net structures are given by using the microelement method in this paper. The differences of the stress contour in the plane of functionally graded plates with different net microstructures are especially given in this paper. 展开更多
关键词 functionally graded materials medium components different net structures three-dimensional analyses microelement method span-scale analyses
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Analyses on Marketing Strategies of Penglai's Tourism
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作者 徐宜华 《海外英语》 2013年第7X期285-288,共4页
Although tourism marketing has made great progress in recent years,researches on it are far from enough.Current re searches on tourism marketing at home and abroad lack pertinence and mostly provide theoretical basis ... Although tourism marketing has made great progress in recent years,researches on it are far from enough.Current re searches on tourism marketing at home and abroad lack pertinence and mostly provide theoretical basis for tourism development within a wide range.The researches on tourism marketing of Penglai are few and far between.Based on previous studies and the status quo of tourism marketing strategy,the below statements tries to find out existing problems of Penglai's tourism,put for ward countermeasures and propose feasible marketing patterns suitable for its tourism development.It subsequently concludes that it can make contribution to the sustainable development of Penglai's tourism and provide other county-level tourism cities with reference for marketing tourism marketing strategies. 展开更多
关键词 Penglai TOURISM MARKETING STRATEGY analyses
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Parametric analyses on dynamic stall control of rotor airfoil via synthetic jet 被引量:11
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作者 Qijun ZHAO Yiyang MA Guoqing ZHAO 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2017年第6期1818-1834,共17页
The effects of synthetic jet control on unsteady dynamic stall over rotor airfoil are investigated numerically. A moving-embedded grid method and an Unsteady Reynolds Averaged Navier-Stokes(URANS) solver coupled wit... The effects of synthetic jet control on unsteady dynamic stall over rotor airfoil are investigated numerically. A moving-embedded grid method and an Unsteady Reynolds Averaged Navier-Stokes(URANS) solver coupled with k-x Shear Stress Transport(SST) turbulence model are established for predicting the complex flowfields of oscillatory airfoil under jet control. Additionally, a velocity boundary condition modeled by sinusoidal function has been developed to fulfill the perturbation effect of periodic jet. The validity of present CFD method is evaluated by comparisons of the calculated results of baseline dynamic stall case for rotor airfoil and jet control case for VR-7 B airfoil with experimental data. Then, parametric analyses are conducted emphatically for an OA212 rotor airfoil to investigate the effects of jet control parameters(jet location, dimensionless frequency, momentum coefficient, jet angle, jet type and dual-jet) on dynamic stall characteristics of rotor airfoil. It is demonstrated by the calculated results that efficiency of jet control could be improved with specific momentum coefficient and jet angle when the jet is located near separation point of rotor airfoil. Furthermore, the dual-jet could improve control efficiency more obviously on dynamic stall of rotor airfoil with respect to the unique jet, and the influence laws of dual-jet's angles and momentum coefficients on control effects are similar to those of the unique jet. Finally,unsteady aerodynamic characteristics of rotor via synthetic jet which is located on the upper surface of rotor blade in forward flight are calculated, and as a result, the aerodynamic characteristics of rotor are improved compared with the baseline. The results indicate that synthetic jet has the capability in improving aerodynamic characteristics of rotor. 展开更多
关键词 AIRFOIL Dynamic stall characteristics:Flow control Moving-embedded gridmethodology Navier-Stokes equations Parametric analyses ROTOR Synthetic jet
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Detailed Inventory Mapping and Spatial Analyses to Landslides Induced by the 2013 Ms 6.6 Minxian Earthquake of China 被引量:11
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作者 Yingying Tian Chong Xu +1 位作者 Xiwei Xu Jian Chen 《Journal of Earth Science》 SCIE CAS CSCD 2016年第6期1016-1026,共11页
On July 22, 2013, an earthquake (Ms 6.6) occurred in Minxian, Gansu Province of China, causing a large number of landslides. Based on high resolution remote sensing images before and after this event, we made the vi... On July 22, 2013, an earthquake (Ms 6.6) occurred in Minxian, Gansu Province of China, causing a large number of landslides. Based on high resolution remote sensing images before and after this event, we made the visual interpretation to these coseismic landslides, and prepared a detailed inventory. The inventory registers totally 6 478 landslides in the study area. Of them, 3 322 landslides are larger than 100 m2. Based on 5 m resolution DEM, these landslides were used to perform spatial analyses using landslide number density (LND) and landslide area percentage (LAP). The results show that the highest LND and LAP values are in the elevation range of 2 300-2 500 m and steeper slopes. Slopes facing E, SE, S and SW directions, slopes with larger absolute curvature values, ridges, scopes of gravel beds of Late Pleistocene (Qp) and the VIII-degree seismic intensity are more prone to sliding with high LND and LAP values. The largest LND and LAP values are in the scopes of 0.08 and 0.24 g, respectively. According to landslide distribution, we infer that F2-2 branch of Lintan-Dangchang fault is the seismogenic fault. With the increasing distances to this branch fault and drainages, LND and LAP values tend to decrease. 展开更多
关键词 Minxian Earthquake landslide inventory spatial analyses landslide number density (LND) landslide area percentage (LAP).
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Study on dynamic response of embedded long span corrugated steel culverts using scaled model shaking table tests and numerical analyses 被引量:12
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作者 车爱兰 IWATATE Takahiro 葛修润 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第3期430-435,共6页
A series of scaled-model shaking table tests and its simulation analyses using dynamic finite element method were performed to clarify the dynamic behaviors and the seismic stability of embedded corrugated steel culve... A series of scaled-model shaking table tests and its simulation analyses using dynamic finite element method were performed to clarify the dynamic behaviors and the seismic stability of embedded corrugated steel culverts due to strong earth-quakes like the 1995 Hyogoken-nanbu earthquake. The dynamic strains of the embedded culvert models and the seismic soil pressure acting on the models due to sinusoidal and random strong motions were investigated. This study verified that the cor-rugated culvert model was subjected to dynamic horizontal forces (lateral seismic soil pressure) from the surrounding ground, which caused the large bending strains on the structure; and that the structures do not exceed the allowable plastic deformation and do not collapse completely during strong earthquake like Hyogoken-nanbu earthquake. The results obtained are useful for design and construction of embedded long span corrugated steel culverts in seismic regions. 展开更多
关键词 Embedded corrugated steel culverts Shaking table tests Hyogoken-nanbu earthquake Dynamic analyses
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Sensitivity analyses of different vegetations responding to climate change in inland river basin of China 被引量:8
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作者 Hou Peng Wang Qiao +3 位作者 Cao Guangzhen Wang Changzuo Zhan Zhiming Yang Bingfeng 《Journal of Geographical Sciences》 SCIE CSCD 2012年第3期387-406,共20页
Terrestrial ecosystem and climate system are closely related to each other. Faced with the unavoidable global climate change, it is important to investigate terrestrial ecosystem responding to climate change. In inlan... Terrestrial ecosystem and climate system are closely related to each other. Faced with the unavoidable global climate change, it is important to investigate terrestrial ecosystem responding to climate change. In inland river basin of arid and semi-arid regions in China, sensitivity difference of vegetation responding to climate change from 1998 to 2007 was analyzed in this paper. (1) Differences in the global spatio-temporal distribution of vegetation and climate are obvious. The vegetation change shows a slight degradation in this whole region. Degradation is more obvious in densely vegetated areas. Temperature shows a general downward trend with a linear trend coefficient of -1.1467. Conversely, precipitation shows an increasing trend with a linear trend coefficient of 0.3896. (2) About the central tendency response, there are similar features in spatial distribution of both NDVI responding to precipitation (NDVI-P) and NDVI responding to AI (NDVI-AI), which are contrary to that of NDVI responding to air temperature (NDVI-T). Typical sensitivity region of NDVI-P and NDVI-AI mainly covers the northern temperate arid steppe and the northern temperate desert steppe. NDVI-T typical sensitivity region mainly covers the northern temperate desert steppe. (3) Regarding the fluctuation amplitude response, NDVI-T is dominated by the lower sensitivity, typical regions of the warm temperate shrubby, selui-shrubby, bare extreme dry desert, and northern temperate meadow steppe in the east and temperate semi-shrubby, dwarf arboreous desert in the north are high response. (4) Fluctuation amplitude responses between NDVI-P and NDVI-AI present a similar spatial distribution. The typical sensitivity region mainly covers the northern temperate desert steppe. There are various linear change trend responses of NDVI-T, NDVI-P and NDVI-AI. As to the NDVI-T and NDVI-AI, which are influenced by the boundary effect of semi-arid and semi-humid climate zones, there is less correlation of their linear change tendency along the border. There is stronger correlation in other regions, especially in the NDVI-T in the northern temperate desert steppe and NDVI-AI in the warm temperate shrubby, selui-shrubby, bare, extreme and dry desert. 展开更多
关键词 VEGETATION CLIMATE satellite images sensitivity analyses inland river basin China
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A Hybrid Neural Network Model for ENSO Prediction in Combination with Principal Oscillation Pattern Analyses 被引量:10
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作者 Lu ZHOU Rong-Hua ZHANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2022年第6期889-902,共14页
El Niño-Southern Oscillation(ENSO)can be currently predicted reasonably well six months and longer,but large biases and uncertainties remain in its real-time prediction.Various approaches have been taken to impro... El Niño-Southern Oscillation(ENSO)can be currently predicted reasonably well six months and longer,but large biases and uncertainties remain in its real-time prediction.Various approaches have been taken to improve understanding of ENSO processes,and different models for ENSO predictions have been developed,including linear statistical models based on principal oscillation pattern(POP)analyses,convolutional neural networks(CNNs),and so on.Here,we develop a novel hybrid model,named as POP-Net,by combining the POP analysis procedure with CNN-long short-term memory(LSTM)algorithm to predict the Niño-3.4 sea surface temperature(SST)index.ENSO predictions are compared with each other from the corresponding three models:POP model,CNN-LSTM model,and POP-Net,respectively.The POP-based pre-processing acts to enhance ENSO-related signals of interest while filtering unrelated noise.Consequently,an improved prediction is achieved in the POP-Net relative to others.The POP-Net shows a high-correlation skill for 17-month lead time prediction(correlation coefficients exceeding 0.5)during the 1994-2020 validation period.The POP-Net also alleviates the spring predictability barrier(SPB).It is concluded that value-added artificial neural networks for improved ENSO predictions are possible by including the process-oriented analyses to enhance signal representations. 展开更多
关键词 ENSO prediction the principal oscillation pattern(POP)analyses neural network a hybrid approach
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Entransy analyses of heat–work conversion systems with inner irreversible thermodynamic cycles 被引量:9
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作者 程雪涛 梁新刚 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第12期259-264,共6页
In this paper, we try to use the entransy theory to analyze the heat–work conversion systems with inner irreversible thermodynamic cycles. First, the inner irreversible thermodynamic cycles are analyzed. The influenc... In this paper, we try to use the entransy theory to analyze the heat–work conversion systems with inner irreversible thermodynamic cycles. First, the inner irreversible thermodynamic cycles are analyzed. The influences of different inner irreversible factors on entransy loss are discussed. We find that the concept of entransy loss can be used to analyze the inner irreversible thermodynamic cycles. Then, we analyze the common heat–work conversion systems with inner irreversible thermodynamic cycles. As an example, the heat–work conversion system in which the working fluid of the thermodynamic cycles is heated and cooled by streams is analyzed. Our analyses show that larger entransy loss leads to larger output work when the total heat flow from the high temperature heat source and the corresponding equivalent temperature are fixed.Some numerical cases are presented, and the results verify the theoretical analyses. On the other hand, it is also found that larger entransy loss does not always lead to larger output work when the preconditions are not satisfied. 展开更多
关键词 entransy loss heat–work conversion inner irreversible thermodynamic cycle analyses
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Mathematical analyses of the GPS receiver interference tolerance and mean time to loss lock 被引量:5
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作者 Ehab M.Shaheen Sherif A.Elgamel 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2019年第3期440-449,共10页
In this paper, novel mathematical expressions are derived for the Global Positioning System (GPS) receiver interference tolerance in the presence of different types of interference signals such as: continuous wave int... In this paper, novel mathematical expressions are derived for the Global Positioning System (GPS) receiver interference tolerance in the presence of different types of interference signals such as: continuous wave interference, narrowband interference, partial band interference, broadband interference, match spectrum interference and pulse interference. Also, in this paper the mean time to loss lock is determined in order to analyse the mentioned interferences effect on the GPS receiver. These derived analytical expressions are validated with the aid of extensive simulation experiments. 展开更多
关键词 MATHEMATICAL analyses GPS RECEIVER INTERFERENCE TOLERANCE
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Provenance Analyses of Lower Cretaceous Strata in the Liupanshan Basin: From Paleocurrents Indicators, Conglomerate Clast Compositions, and Zircon U-Pb Geochronology 被引量:6
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作者 Xiaochen Zhao Chiyang Liu +3 位作者 Jianqiang Wang Wei Luo Fangpeng Du Li Ma 《Journal of Earth Science》 SCIE CAS CSCD 2020年第4期757-771,共15页
The Liupanshan Basin constitutes a major portion of the northern North-South tectonic belt. The Lower Cretaceous strata in the Liupanshan Basin recorded the tectono-sedimentary evolution processes of this area and are... The Liupanshan Basin constitutes a major portion of the northern North-South tectonic belt. The Lower Cretaceous strata in the Liupanshan Basin recorded the tectono-sedimentary evolution processes of this area and are pivotal for understanding the original sedimentary appearance of the Liupanshan Basin. In this work, we present a study of provenance and tectono-sedimentary evolution of the Liupanshan Basin during the Early Cretaceous. Integrated-paleocurrent directions, gravel clast compositions, and detrital zircon U-Pb isotopic analysis of the Lower Cretaceous Sanqiao and Heshangpu formations were applied to determine the provenance. The gravel clast compositions of Sanqiao Formation conglomerates(mainly including magmatic rocks, metamorphic rocks and limestones) display various features in different places, revealing different rock components of source areas. The paleocurrent directions of the Sanqiao and Heshangpu formations suggest that the sediments were transported from the basin margin to the center. Detrital zircons of two samples from the Huoshizhai Section(northwestern Liupanshan Basin) yield a dominant unimodal distribution from 420 to 500 Ma, suggesting a single-sourced provenance. Based on the above analyses, comparing to the magmatic records in the Qilian-Qinling orogenic belt, the detritus of the Sanqiao and Heshangpu formations were mainly from the proximal metamorphic and magmatic rocks of the Qilian-Qinling orogenic belt and the limestones of the archaic uplift. Combined with sedimentary characteristics, we concluded that the Liupanshan Basin experienced multi-stage evolution history:(1) the early rifting extension stage(Sanqiao Period),(2) the middle spanning and depression stage(Heshangpu–Early Naijiahe Period), and(3) the late extinction stage(Late Naijiahe Period). The evolution of Liupanshan Basin is closely related to that of Ordos Basin and it is further associated with tectonic transition of the northern North-South tectonic belt. 展开更多
关键词 provenance analyses tectono-sedimentary evolution Liupanshan Basin Lower Cretaceous North-South tectonic belt
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Increased virulence of the oral microbiome in oral squamous cell carcinoma revealed by metatranscriptome analyses 被引量:10
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作者 Susan Yost Philip Stashenko +6 位作者 Yoonhee Choi Maria Kukuruzinska Caroline A.Genco Andrew Salama Ellen O.Weinberg Carolyn D.Kramer Jorge Frias-Lopez 《International Journal of Oral Science》 SCIE CAS CSCD 2018年第4期263-272,共10页
Oral squamous cell carcinoma(OSCC) is the most prevalent and most commonly studied oral cancer. However, there is a void regarding the role that the oral microbiome may play in OSCC. Although the relationship between ... Oral squamous cell carcinoma(OSCC) is the most prevalent and most commonly studied oral cancer. However, there is a void regarding the role that the oral microbiome may play in OSCC. Although the relationship between microbial community composition and OSCC has been thoroughly investigated, microbial profiles of the human microbiome in cancer are understudied. Here we performed a small pilot study of community-wide metatranscriptome analysis to profile mRNA expression in the entire oral microbiome in OSCC to reveal molecular functions associated with this disease. Fusobacteria showed a statistically significantly higher number of transcripts at tumour sites and tumour-adjacent sites of cancer patients compared to the healthy controls analysed. Regardless of the community composition, specific metabolic signatures were consistently found in disease. Activities such as iron ion transport, tryptophanase activity, peptidase activities and superoxide dismutase were over-represented in tumour and tumour-adjacent samples when compared to the healthy controls. The expression of putative virulence factors in the oral communities associated with OSCC showed that activities related to capsule biosynthesis, flagellum synthesis and assembly, chemotaxis, iron transport, haemolysins and adhesins were upregulated at tumour sites. Moreover, activities associated with protection against reactive nitrogen intermediates, chemotaxis, flagellar and capsule biosynthesis were also upregulated in non-tumour sites of cancer patients. Although they are preliminary, our results further suggest that Fusobacteria may be the leading phylogenetic group responsible for the increase in expression of virulence factors in the oral microbiome of OSCC patients. 展开更多
关键词 profiles analyses
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Phylogenetic relationships of the zokor genus Eospalax(Mammalia,Rodentia,Spalacidae)inferred from whole-genome analyses,with description of a new species endemic to Hengduan Mountains 被引量:4
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作者 Tao Zhang Meng-Long Lei +2 位作者 Hao Zhou Zhong-Zheng Chen Peng Shi 《Zoological Research》 SCIE CAS CSCD 2022年第3期331-342,共12页
Zokors in the genus Eospalax,which are endemic to northern and western China,are subterranean rodents that inhabit various niches,including grasslands,high-altitude meadows,forests,and farmlands.Six species in Eospala... Zokors in the genus Eospalax,which are endemic to northern and western China,are subterranean rodents that inhabit various niches,including grasslands,high-altitude meadows,forests,and farmlands.Six species in Eospalax were described a century ago but their taxonomy and phylogeny remain controversial.In this study,we performed high-depth whole-genome sequencing of 47 zokor samples,comprising all six previously described species.Genomic analyses revealed a reliable and robust phylogeny of Eospalax and supported the validity of the six named species.According to the inferred phylogenetic relationships,Eospalax first divergent into two clades in the early Pliocene(ca.4.68 million years ago(Ma)),one inhabiting the highaltitude Qinghai-Xizang(Tibet)Plateau(QTP)and adjacent regions,and the another inhabiting the lowaltitude Loess Plateau and Qinling-Daba Mountains.The most recent divergences occurred between E.baileyi and E.smithii and between E.rufescens and E.rothschildi in the late Pliocene(ca.2.09 and 2.19 Ma,respectively).We also collected specimens of zokors in the southern Hengduan Mountains(Muli County,Sichuan Province),far from the known distributions of all other zokors.Morphological and molecular analyses strongly suggested that the specimens represent a new species,formally described here as Eospalax muliensis sp.nov.The new species belongs to the high-altitude clade and diverged from closely related species(ca.4.22 Ma)shortly after the first divergence in Eospalax.Interestingly,Eospalax muliensis sp.nov.possesses more supposedly plesiomorphic characters,suggesting a possible origin of the genus in the Hengduan Mountains. 展开更多
关键词 ZOKOR Eospalax Phylogenomic analyses New species Hengduan Mountains
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