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Utilization of Hot Spotting to Identify Community Needs and Coordinate Care for High-Cost Patients in Memphis, TN
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作者 Teresa Cutts Edward Rafalski +1 位作者 Cori Grant Razvan Marinescu 《Journal of Geographic Information System》 2014年第1期23-29,共7页
In 2006, Methodist Le Bonheur Healthcare (MLH) created the Congregational Health Network (CHN, TM pending) which works closely with clergy in the most under-served zip codes of the city to improve access to care and o... In 2006, Methodist Le Bonheur Healthcare (MLH) created the Congregational Health Network (CHN, TM pending) which works closely with clergy in the most under-served zip codes of the city to improve access to care and overall health status of the population. To best coordinate CHN resources around high-utilization and address the largest health needs in the community, MLH applied hot spotting and geographic information system (GIS) spatial analysis techniques. These techniques were coupled with the community health needs assessment process at MLH and qualitative, participatory research findings captured in collaboration with church and other community partners. The methodology, which we call “participatory hot spotting,” is based upon the Camden Model, which leverages hot spotting to assess and prioritize community need in the provision of charity care, but adds a participatory, qualitative layer. In this study, spatial analysis was employed to evaluate hospital-based inpatient and outpatient utilization and define costs of charity care for the health system by area of residence. Ten zip codes accounted for 56% of total system charity care costs. Among these, the largest zip code, as defined by a percentage of total charity costs, contributed 18% of the inpatient utilization and 17% of the cost. Further, this zip code (38109) contributed 69% of the inpatient and 76% of the outpatient charity care volume and accounted for 75% of inpatient and 76% of outpatient charity care costs for the system. These findings were combined with grassroots intelligence that enabled a partnership with clergy and community members and Cigna Healthcare to better coordinate care in a place-based population health management strategy. Presentations of the analytics have subsequently been made to HHS and the CDC, referred to by some as the “Memphis Model”. 展开更多
关键词 Hot Spotting CHNA (Community HEALTH Needs Assessment) Congregational HEALTH Network (CHN) MEMPHIS Model HEALTH DISPARITIES
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Cortical hem signaling center: functions, development, and potential implications for evolution and brain disorders
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作者 Victor V.Chizhikov Igor Y.Iskusnykh 《Neural Regeneration Research》 SCIE CAS 2025年第4期1079-1080,共2页
Development of the telencephalon relies upon several signaling centers-localized cellular populations that supply secreted factors to pattern the cortical neuroepithelium.One such signaling center is the cortical hem,... Development of the telencephalon relies upon several signaling centers-localized cellular populations that supply secreted factors to pattern the cortical neuroepithelium.One such signaling center is the cortical hem,which arises during embryonic development at the telencephalic dorsal midline,adjacent to the choroid plexus and hippocampal primordium(Figure 1A).While the cortical hem has also been described in reptiles and birds,most of our knowledge about the developmental roles of the cortical hem is derived from the analysis in mice.The cortical hem produces several types of secreted molecules,including wingless-related integration site(Wnt)and bone morphogenetic(Bmp)proteins.The cortical hem is particularly important for the development of the hippocampus,which is involved in learning and memory,and the neocortex,which is the most complex brain region that mediates multiple types of behavior and higher cognitive functions(Mangale et al.,2008;Dal-Valle-Anton and Borrell,2022). 展开更多
关键词 EPITHELIUM FIGURE CENTER
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New insights into the therapeutic approaches for the treatment of tauopathies 被引量:2
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作者 Himanshi Singh Asmita Das +1 位作者 Mohammad Moshahid Khan Tayebeh Pourmotabbed 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第5期1020-1026,共7页
Tauopathies are a group of neurological disorders,including Alzheimer’s disease and frontotemporal dementia,which involve progressive neurodegeneration,cognitive deficits,and aberrant tau protein accumulation.The dev... Tauopathies are a group of neurological disorders,including Alzheimer’s disease and frontotemporal dementia,which involve progressive neurodegeneration,cognitive deficits,and aberrant tau protein accumulation.The development of tauopathies cannot currently be stopped or slowed down by treatment measures.Given the significant contribution of tau burden in primary tauopathies and the strong association between pathogenic tau accumulation and cognitive deficits,there has been a lot of interest in creating therapies that can alleviate tau pathology and render neuroprotective effects.Recently,small molecules,immunotherapies,and gene therapy have been used to reduce the pathological tau burden and prevent neurodegeneration in animal models of tauopathies.However,the major pitfall of the current therapeutic approach is the difficulty of drugs and gene-targeting modalities to cross the blood-brain barrier and their unintended side effects.In this review,the current therapeutic strategies used for tauopathies including the use of oligonucleotide-based gene therapy approaches that have shown a promising result for the treatment of tauopathies and Alzheimer’s disease in preclinical animal models,have been discussed. 展开更多
关键词 DEMENTIA gene therapies IMMUNOTHERAPY NEURODEGENERATION OLIGONUCLEOTIDES tau TAUOPATHIES THERAPIES
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Modulation of p75 neurotrophin receptor mitigates brain damage following ischemic stroke in mice 被引量:1
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作者 Golnoush Mirzahosseini Tauheed Ishrat 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第10期2093-2094,共2页
Stroke is a significant leading cause of death and disability in the United States(Tsao et al.,2022).Approximately 87% of strokes fall into the ischemic category,mainly caused by arterial blockage(Jayaraj et al.,2019)... Stroke is a significant leading cause of death and disability in the United States(Tsao et al.,2022).Approximately 87% of strokes fall into the ischemic category,mainly caused by arterial blockage(Jayaraj et al.,2019).Although the only FDA-approved effective medication is tissue plasminogen activator(tPA),it should be administrated within 4.5 hours of ischemic stroke.Furthermore,tPA has been an integral part of managing acute ischemic stro ke. 展开更多
关键词 damage ARTERIAL DEATH P75
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Anti-tumor efficacy of Calculus bovis: Suppressing liver cancer by targeting tumor-associated macrophages
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作者 Ishita Kathuria Bhupesh Singla 《World Journal of Gastroenterology》 SCIE CAS 2024年第38期4249-4253,共5页
Despite significant advances in our understanding of the molecular pathogenesis of liver cancer and the availability of novel pharmacotherapies,liver cancer remains the fourth leading cause of cancer-related mortality... Despite significant advances in our understanding of the molecular pathogenesis of liver cancer and the availability of novel pharmacotherapies,liver cancer remains the fourth leading cause of cancer-related mortality worldwide.Tumor relapse,resistance to current anti-cancer drugs,metastasis,and organ toxicity are the major challenges that prevent considerable improvements in patient survival and quality of life.Calculus bovis(CB),an ancient Chinese medicinal drug,has been used to treat various pathologies,including stroke,convulsion,epilepsy,pain,and cancer.In this editorial,we discuss the research findings recently published by Huang et al on the therapeutic effects of CB in inhibiting the development of liver cancer.Utilizing the comprehensive transcriptomic analyses,in vitro experiments,and in vivo studies,the authors demonstrated that CB treatment inhibits the tumor-promoting M2 phenotype of tumor-associated macrophages via downregulating Wnt pathway.While multiple studies have been performed to explore the molecular mechanisms regulated by CB,this study uniquely shows its role in modulating the M2 phenotype of macrophages present within the tumor microenvironment.This study opens new avenues of future investigations aimed at investigating this drug’s efficacy in various mouse models including the effects of combination therapy,and against drug-resistant tumors. 展开更多
关键词 Calculus bovis Liver cancer M2-like tumor associated macrophages Wnt/β-catenin pathway Tumor environment
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Assessment of scale interactions associated with wake meandering using bispectral analysis methodologies
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作者 Dinesh Kumar Kinjangi Daniel Foti 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2024年第2期65-75,共11页
Large atmospheric boundary layer fluctuations and smaller turbine-scale vorticity dynamics are separately hypothesized to initiate the wind turbine wake meandering phenomenon,a coherent,dynamic,turbine-scale oscillati... Large atmospheric boundary layer fluctuations and smaller turbine-scale vorticity dynamics are separately hypothesized to initiate the wind turbine wake meandering phenomenon,a coherent,dynamic,turbine-scale oscillation of the far wake.Triadic interactions,the mechanism of energy transfers between scales,manifest as triples of wavenumbers or frequencies and can be characterized through bispectral analyses.The bispectrum,which correlates the two frequencies to their sum,is calculated by two recently developed multi-dimensional modal decomposition methods:scale-specific energy transfer method and bispectral mode decomposition.Large-eddy simulation of a utility-scale wind turbine in an atmospheric boundary layer with a broad range of large length-scales is used to acquire instantaneous velocity snapshots.The bispectrum from both methods identifies prominent upwind and wake meandering interactions that create a broad range of energy scales including the wake meandering scale.The coherent kinetic energy associated with the interactions shows strong correlation between upwind scales and wake meandering. 展开更多
关键词 Wind turbine wake Mode decomposition Bispectral analysis
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ON A UNIVERSAL INEQUALITY FOR APPROXIMATE PHASE ISOMETRIES
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作者 戴端旭 阙海新 +1 位作者 孙龙发 郑本拓 《Acta Mathematica Scientia》 SCIE CSCD 2024年第3期823-838,共16页
Let X and Y be two normed spaces.Let U be a non-principal ultrafilter on N.Let g:X→Y be a standard ε-phase isometry for someε≥ 0,i.e.,g(0)=0,and for all u.v ∈ X,||‖g(u)+g(v)‖±‖g(u)-g(v)‖|-|‖u+v‖±... Let X and Y be two normed spaces.Let U be a non-principal ultrafilter on N.Let g:X→Y be a standard ε-phase isometry for someε≥ 0,i.e.,g(0)=0,and for all u.v ∈ X,||‖g(u)+g(v)‖±‖g(u)-g(v)‖|-|‖u+v‖±‖u-v‖| |≤ε.The mapping g is said to be a phase isometry provided that ε=0.In this paper,we show the following universal inequality of g:for each u^(*) ∈ w^(*)-exp ‖u^(*)‖B_(x^(*)),there exist a phase function σ_(u^(*)):X→{-1,1} and φ ∈ Y^(*) with ‖φ‖=‖u^(*)‖≡α satisfying that|(u^(*),u)-σ_(u^(*))(u)<φ,g(u)>)|≤5/2εα,for all u ∈ X.In particular,let X be a smooth Banach space.Then we show the following:(1) the universal inequality holds for all u^(*) ∈ X^(*);(2) the constant 5/2 can be reduced to 3/2 provided that Y~*is strictly convex;(3) the existence of such a g implies the existence of a phase isometryΘ:X→Y such that■ provided that Y^(**) has the w^(*)-Kadec-Klee property(for example,Y is both reflexive and locally uniformly convex). 展开更多
关键词 ε-phase isometry phase isometry Banach space
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A 63-Year-Old Male with D-Transposition of the Great Arteries Who Had an Early Form of the Arterial Switch Operation
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作者 Michael A.Rebolledo Jane S.Yao +2 位作者 Jason N.Johnson Umar S.Boston Benjamin R.Waller III 《Congenital Heart Disease》 SCIE 2024年第1期65-68,共4页
We describe a 63-year-old male who appears to have undergone an early form of the arterial switch operation for D-transposition of the great arteries performed in the mid-1960s.We review the clinical and imaging data ... We describe a 63-year-old male who appears to have undergone an early form of the arterial switch operation for D-transposition of the great arteries performed in the mid-1960s.We review the clinical and imaging data that support our conclusion.He had a diagnostic cardiac catheterization which demonstrated severe pulmonary hypertension responsive to epoprostenol and oxygen.Our case may represent one example of the experimental surgical work done prior to Dr.Adibe Jatene’s description of thefirst successful arterial switch performed in 1975. 展开更多
关键词 Adult congenital heart disease arterial switch operation great vessel anomaly imaging(all modalities)
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Role of intravascular ultrasound and optical coherence tomography in intracoronary imaging for coronary artery disease:a systematic review
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作者 Maruf Sarwar Stephen Adedokun Mahesh Anantha Narayanan 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2024年第1期104-129,共26页
Coronary angiography has long been the standard for coronary imaging,but it has limitations in assessing vessel wall anatomy and guiding percutaneous coronary intervention(PCI).Intracoronary imaging techniques like in... Coronary angiography has long been the standard for coronary imaging,but it has limitations in assessing vessel wall anatomy and guiding percutaneous coronary intervention(PCI).Intracoronary imaging techniques like intravascular ultrasound(IVUS)and optical coherence tomography(OCT)can overcome these limitations.IVUS uses ultrasound and OCT uses near-infrared light to visualize coronary pathology in unique ways due to differences in temporal and spatial resolution.These techniques have evolved to offer clinical utility in plaque characterization and vessel assessment during PCI.Meta-analyses and adjusted observational studies suggest that both IVUS and OCT-guided PCI correlate with reduced cardiovascular risks compared to angiographic guidance alone.While IVUS demonstrates consistent clinical outcome benefits,OCT evidence is less robust.IVUS has progressed from early motion detection to high-resolution systems,with smaller compatible catheters.OCT utilizes near infrared light to achieve unparalleled resolutions,but requires temporary blood clearance for optimal imaging.Enhanced visualization and guidance make IVUS and OCT well-suited for higher risk PCI in patients with diabetes and chronic kidney disease by allowing detailed visualization of complex lesions and ensuring optimal stent deployment and positioning in PCI for patients with type 2 diabetes and chronic kidney disease,improving outcomes.IVUS and recent advancements in zero-and low-contrast OCT techniques can reduce nephrotoxic contrast exposure,thus helping to minimize PCI complications in these high-risk patient groups.IVUS and OCT provide valuable insights into coronary pathophysiology and guide interventions precisely compared to angiography alone.Both have comparable clinical outcomes,emphasizing the need for tailored imaging choices based on clinical scenarios.Continued refinement and integration of intravascular imaging will likely play a pivotal role in optimizing coronary interventions and outcomes.This systematic review aims to delve into the nuances of IVUS and OCT,highlighting their strengths and limitations as PCI adjuncts. 展开更多
关键词 CORONARY ANATOMY LIMITATIONS
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Seismic anisotropy and upper mantle dynamics in Alaska:A review of shear wave splitting analyses
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作者 Zhaofeng Jin Yuchen Yang +7 位作者 Muhammad Ishaidir Siregar Zihao Mu S.M.Ariful Islam Qichao Zhao Dan Wang Fan Zhang Xugang Yang Liwei Song 《Earthquake Research Advances》 CSCD 2024年第2期72-81,共10页
Shear wave splitting(SWS)is regarded as the most effective geophysical method to delineate mantle flow fields by detecting seismic azimuthal anisotropy in the earth's upper mantle,especially in tectonically active... Shear wave splitting(SWS)is regarded as the most effective geophysical method to delineate mantle flow fields by detecting seismic azimuthal anisotropy in the earth's upper mantle,especially in tectonically active regions such as subduction zones.The Aleutian-Alaska subduction zone has a convergence rate of approximately 50 mm/yr,with a trench length reaching nearly 2800 km.Such a long subduction zone has led to intensive continental deformation and numerous strong earthquakes in southern and central Alaska,while northern Alaska is relatively inactive.The sharp contrast makes Alaska a favorable locale to investigate the impact of subduction on mantle dynamics.Moreover,the uniqueness of this subduction zone,including the unusual subducting type,varying slab geometry,and atypical magmatic activity and composition,has intrigued the curiosity of many geoscientists.To identify different sources of seismic anisotropy beneath the Alaska region and probe the influence of a geometrically varying subducting slab on mantle dynamics,extensive SWS analyses have been conducted in the past decades.However,the insufficient station and azimuthal coverage,especially in early studies,not only led to some conflicting results but also strongly limited the in-depth investigation of layered anisotropy and the estimation of anisotropy depth.With the completion of the Transportable Array project in Alaska,recent studies have revealed more detailed mantle structures and characteristics based on the dense station coverage and newly collected massive seismic data.In this study,we review significant regional-and continental-scale SWS studies in the Alaska region and conclude the mantle flow fields therein,to understand how a geometrically varying subducting slab alters the regional mantle dynamics.The summarized mantle flow mechanisms are believed to be conducive to the understanding of seismic anisotropy patterns in other subduction zones with a complicated tectonic setting. 展开更多
关键词 Seismic anisotropy Shear wave splitting Mantle flow Alaska subduction zone SLAB
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Muscle strength deficits are associated with low bone mineral density in young pediatric cancer survivors:The iBoneFIT project
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作者 Andres Marmol-Perez Jose J.Gil-Cosano +6 位作者 Esther Ubago-Guisado Francisco J.Llorente-Cantarero Juan Francisco Pascual-Gázquez Kirsten K.Ness Vicente Martinez-Vizcaino Jonatan R.Ruiz Luis Gracia-Marco 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第3期419-427,共9页
Background Pediatric cancer survivors are at increased risk of muscle weakness and low areal bone mineral density(aBMD).However,the prevalence of muscle strength deficits is not well documented,and the associations of... Background Pediatric cancer survivors are at increased risk of muscle weakness and low areal bone mineral density(aBMD).However,the prevalence of muscle strength deficits is not well documented,and the associations of muscle strength with aBMD are unknown in this population.Therefore,this study aimed to investigate the prevalence of upper-and lower-body muscle strength deficits and to examine the associations of upper-and lower-body muscle strength with age-,sex,and race-specific aBMD Z-scores at the total body,total hip,femoral neck,and lumbar spine.Methods This cross-sectional study included 116 pediatric cancer survivors(12.1±3.3 years old,mean±SD;42.2%female).Upper-and lower-body muscle strength were assessed by handgrip and standing long jump test,respectively.Dual‑energy X‑ray absorptiometry was used to measure aBMD(g/cm2).Associations between muscle strength and aBMD were evaluated in multivariable linear regression models.Logistic regression was used to evaluate the contribution of muscle strength(1-decile lower)to the odds of having low aBMD(Z-score≤1.0).All analyses were adjusted for time from treatment completion,radiotherapy exposure,and body mass index.Results More than one-half of survivors were within the 2 lowest deciles for upper-(56.9%)and lower-body muscle strength(60.0%)in comparison to age-and sex-specific reference values.Muscle strength deficits were associated with lower aBMD Z-scores at all sites(B=0.133–0.258,p=0.001–0.032).Each 1-decile lower in upper-body muscle strength was associated with 30%–95%higher odds of having low aBMD Z-scores at all sites.Each 1-decile lower in lower-body muscle strength was associated with 35%–70%higher odds of having low aBMD Z-scores at total body,total hip,and femoral neck.Conclusion Muscle strength deficits are prevalent in young pediatric cancer survivors,and such deficits are associated with lower aBMD Z-scores at all sites.These results suggest that interventions designed to improve muscle strength in this vulnerable population may have the added benefit of improving aBMD. 展开更多
关键词 Bone health Childhood cancer DXA Lean mass Resistance training
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Analyzing the Impact of Scene Transitions on Indoor Camera Localization through Scene Change Detection in Real-Time
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作者 Muhammad S.Alam Farhan B.Mohamed +2 位作者 Ali Selamat Faruk Ahmed AKM B.Hossain 《Intelligent Automation & Soft Computing》 2024年第3期417-436,共20页
Real-time indoor camera localization is a significant problem in indoor robot navigation and surveillance systems.The scene can change during the image sequence and plays a vital role in the localization performance o... Real-time indoor camera localization is a significant problem in indoor robot navigation and surveillance systems.The scene can change during the image sequence and plays a vital role in the localization performance of robotic applications in terms of accuracy and speed.This research proposed a real-time indoor camera localization system based on a recurrent neural network that detects scene change during the image sequence.An annotated image dataset trains the proposed system and predicts the camera pose in real-time.The system mainly improved the localization performance of indoor cameras by more accurately predicting the camera pose.It also recognizes the scene changes during the sequence and evaluates the effects of these changes.This system achieved high accuracy and real-time performance.The scene change detection process was performed using visual rhythm and the proposed recurrent deep architecture,which performed camera pose prediction and scene change impact evaluation.Overall,this study proposed a novel real-time localization system for indoor cameras that detects scene changes and shows how they affect localization performance. 展开更多
关键词 Camera pose estimation indoor camera localization real-time localization scene change detection simultaneous localization and mapping(SLAM)
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Gut microbial metabolite targets HDAC3-FOXK1-interferon axis in fibroblast-like synoviocytes to ameliorate rheumatoid arthritis
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作者 Hongzhen Chen Xuekun Fu +15 位作者 Xiaohao Wu Junyi Zhao Fang Qiu Zhenghong Wang Zhuqian Wang Xinxin Chen Duoli Xie Jie Huang Junyu Fan Xu Yang Yi Song Jie Li Dongyi He Guozhi Xiao Aiping Lu Chao Liang 《Bone Research》 SCIE CAS CSCD 2024年第2期421-437,共17页
Rheumatoid arthritis(RA)is an autoimmune disease.Early studies hold an opinion that gut microbiota is environmentally acquired and associated with RA susceptibility.However,accumulating evidence demonstrates that gene... Rheumatoid arthritis(RA)is an autoimmune disease.Early studies hold an opinion that gut microbiota is environmentally acquired and associated with RA susceptibility.However,accumulating evidence demonstrates that genetics also shape the gut microbiota.It is known that some strains of inbred laboratory mice are highly susceptible to collagen-induced arthritis(CIA),while the others are resistant to CIA.Here,we show that transplantation of fecal microbiota of CIA-resistant C57BL/6J mice to CIA-susceptible DBA/1J mice confer CIA resistance in DBA/1J mice.C57BL/6J mice and healthy human individuals have enriched B.fragilis than DBA/1J mice and RA patients.Transplantation of B.fragilis prevents CIA in DBA/1J mice.We identify that B.fragilis mainly produces propionate and C57BL/6J mice and healthy human individuals have higher level of propionate.Fibroblast-like synoviocytes(FLSs)in RA are activated to undergo tumor-like transformation.Propionate disrupts HDAC3-FOXK1 interaction to increase acetylation of FOXK1,resulting in reduced FOXK1 stability,blocked interferon signaling and deactivation of RA-FLSs.We treat CIA mice with propionate and show that propionate attenuates CIA.Moreover,a combination of propionate with anti-TNF etanercept synergistically relieves CIA.These results suggest that B.fragilis or propionate could be an alternative or complementary approach to the current therapies. 展开更多
关键词 HDAC3 cytes INTERFERON
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映秀-北川断裂的地表破裂与变形特征 被引量:58
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作者 李勇 周荣军 +9 位作者 Alexander L.DENSMORE 闫亮 Nicholas RICHARDSON 董顺利 Michael A.ELLIS 张毅 何玉林 陈浩 乔宝成 马博琳 《地质学报》 EI CAS CSCD 北大核心 2008年第12期1688-1706,共19页
2008年5月12日在龙门山映秀-北川断裂带发生的8.0级特大地震,属于逆冲—走滑型地震。本文以地表破裂为切入点,在映秀-北川断裂的关键部位开展了详细的野外地貌测量,标定了映秀-北川断裂带的垂向断距和水平断距,结果表明映秀-北川断裂的... 2008年5月12日在龙门山映秀-北川断裂带发生的8.0级特大地震,属于逆冲—走滑型地震。本文以地表破裂为切入点,在映秀-北川断裂的关键部位开展了详细的野外地貌测量,标定了映秀-北川断裂带的垂向断距和水平断距,结果表明映秀-北川断裂的地表破裂带从映秀向北东延伸达180~190km,走向介于NE30°~50°之间,倾向北西,地表平均垂向断距为2.9m,平均水平断距为3.1m;地表最大错动量的地点位于北川县擂鼓镇,垂直断错为6.2±0.1m,水平断错为6.8±0.2m,逆冲分量与右行走滑分量的比值为3∶1~1∶1,表明该断裂以逆冲—右行走滑为特点,逆冲运动分量略大于或等于右行走滑运动分量。根据近南北向的分段断裂可将映秀-北川断层的地表破裂带划分为两个高值区和两个低值区,其中两个高值区分别位于南段的映秀—虹口一带和中北段的擂鼓—北川县城—邓家坝一带。基于保存于破裂面上的擦痕,我们将该地震破裂过程划分为两个阶段,早期为逆冲作用,晚期为斜向走滑作用。 展开更多
关键词 汶川地震 地表破裂 映秀-北川断裂 走滑-逆冲作用 龙门山
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龙门山地震带的地质背景与汶川地震的地表破裂 被引量:111
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作者 李勇 黄润秋 +10 位作者 周荣军 Alexander L.DENSMORE Michael A.ELLIS 闫亮 董顺利 Nicholas RICHARDSON 张毅 何玉林 陈浩 乔宝成 马博琳 《工程地质学报》 CSCD 北大核心 2009年第1期3-18,共16页
龙门山位于青藏高原与扬子地台之间,系由一系列大致平行的叠瓦状冲断带构成,自西向东发育汶川—茂汶断裂、映秀—北川断裂和彭县—灌县断裂,并将龙门山划分为3个构造地层带,分别为变形变质构造地层带(主要由志留系—泥盆系浅变质岩和前... 龙门山位于青藏高原与扬子地台之间,系由一系列大致平行的叠瓦状冲断带构成,自西向东发育汶川—茂汶断裂、映秀—北川断裂和彭县—灌县断裂,并将龙门山划分为3个构造地层带,分别为变形变质构造地层带(主要由志留系—泥盆系浅变质岩和前寒武系杂岩构成)、变形变位构造地层带(主要由上古生界—三叠系沉积岩构成)、变形构造地层带(主要由侏罗系至第三系红层和第四纪松散堆积构成)。龙门山断裂带属地震危险区,3条主干断裂皆具备发生7级左右地震的能力,其中映秀—北川断裂是引发地震的最主要断层,据对彭县—灌县断裂青石坪探槽场地的研究结果表明,在该断裂带上最晚的一次强震发生在930±40a.B.P.左右,据此,可以初步判定,这3条主干断裂的单条断裂上的强震复发间隔至少应在1000a左右,表明龙门山构造带及其内部断裂属于地震活动频度低但具有发生超强地震的潜在危险的特殊断裂,以逆冲-右行走滑为其主要运动方式。汶川地震属于逆冲—走滑型的地震,地表破裂分布于映秀—北川断裂带和彭县—灌县断裂带上。根据近南北向的断裂(小鱼洞断层、擂鼓断层和邓家坝断层)和地表断距可将映秀—北川断层的地表破裂带划分为两个高值区和两个低值区,两个高值区分别位于南段的映秀-虹口一带和位于中北段的擂鼓—北川县城—邓家坝一带;两个低值区分别位于中南段的白水河—茶坪一带和北段的北川黄家坝至平武石坎子一带,两个高值区分别与小鱼洞断层和擂鼓断层相关。根据保存于破裂面上的擦痕,可将该地震破裂过程划分为两个阶段,早期为逆冲作用,晚期为斜向走滑作用,其与地壳增厚构造模式和侧向挤出摸式在青藏高原东缘的推论具有不吻合性。鉴于龙门山的表层运动速率与深部构造运动速率具有不一致性,初步探讨了龙门山地区的地表过程与下地壳流之间的地质动力模型,认为下地壳物质在龙门山近垂向挤出和垂向运动,从而造成导致龙门山向东的逆冲运动、龙门山构造带抬升和汶川特大地震。在此基础上,根据汶川地震所引发的地质灾害,对地震灾后重建提出了的几点建议。 展开更多
关键词 汶川地震 地表破裂 历史地震 活动构造 走滑—逆冲作用 龙门山地震带 青藏高原
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青藏高原东缘活动构造 被引量:144
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作者 周荣军 李勇 +4 位作者 Alexander L Densmore Michael A Ellis 何玉林 王凤林 黎小刚 《矿物岩石》 CAS CSCD 北大核心 2006年第2期40-51,共12页
青藏高原东缘由岷山断块和龙门山构造带构成。以活动构造地貌学为主线,在解析该地区主干断裂晚第四纪以来活动的地质地貌表现的基础上,对一批断裂运动学和史前强震活动的定量数据进行分析研究,结果表明:在岷山断块中,虎牙断裂的平均左... 青藏高原东缘由岷山断块和龙门山构造带构成。以活动构造地貌学为主线,在解析该地区主干断裂晚第四纪以来活动的地质地貌表现的基础上,对一批断裂运动学和史前强震活动的定量数据进行分析研究,结果表明:在岷山断块中,虎牙断裂的平均左旋滑动速率为1.4 mm/a,垂直滑动速率为0.3 mm/a。岷江断裂的平均垂直滑动速率介于0.37 mm/a^0.53 mm/a之间,左旋位错量与垂直位错量大致相当;在龙门山构造带中,茂汶-汶川断裂、北川-映秀断裂和彭县-灌县断裂的平均垂直滑动速率均在1 mm/a左右,且几条主干断裂的右旋位错量与垂直位错量相当。结合震源机制解结果和GPS测量资料,建立晚新生代以来青藏高原东缘向南东方向逸出的构造变形模式。 展开更多
关键词 构造地貌 滑动速率 强震复发 青藏高原东缘
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龙门山小鱼洞断裂在汶川地震中的地表破裂及地质意义 被引量:34
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作者 李勇 黄润秋 +10 位作者 A.L.Densmore 周荣军 闫亮 张毅 N.Richardson 董顺利 乔宝成 M.A.Ellis 何玉林 陈浩 马博琳 《第四纪研究》 CAS CSCD 北大核心 2009年第3期502-512,共11页
在龙门山中段小鱼洞地区映秀-北川断裂和彭县-灌县断裂发生了同震位移,同时在该地区新出现了一条北西向的同震破裂带——小鱼洞断裂的破裂带,并分割了两条近于平行的北东向逆冲-走滑型的主断裂。汶川特大地震发生后重点对小鱼洞断裂的... 在龙门山中段小鱼洞地区映秀-北川断裂和彭县-灌县断裂发生了同震位移,同时在该地区新出现了一条北西向的同震破裂带——小鱼洞断裂的破裂带,并分割了两条近于平行的北东向逆冲-走滑型的主断裂。汶川特大地震发生后重点对小鱼洞断裂的地表破裂开展了详细的野外地质填图,利用全站仪和GPS对地表破裂进行了精确的测量。初步调查的结果表明,小鱼洞断裂位于映秀-北川断裂与彭县-灌县断裂之间,走向近于北西向,延伸约15km,以脆性破裂为特征,穿过小鱼洞大桥,并切割了多种类型的地貌单元,使道路发生拱曲、破坏和桥梁垮塌或移位。单个破裂长度在几米到300m不等,其南西盘为上升盘,北东盘为下降盘,平均垂直位错为1.0m,平均水平位错为2.3m,垂直与水平位错量之比1:1~1:2,显示为逆冲分量小于或等于左旋走滑分量,并以左旋走滑作用为主。同时,研究表明小鱼洞断裂属于映秀-北川断裂与彭县-灌县断裂之间的捩断层,其主要特征包括:1)是在汶川地震中由于龙门山逆冲体之间的差异逆冲运动过程中而形成的断裂;2)其走向近于北西向,垂直于龙门山北东向的主干断裂,而平行于逆冲体的逆冲运动方向;3)具有高角度断面的断层,以左旋走滑作用为主。 展开更多
关键词 汶川地震 地表破裂 小鱼洞捩断裂 组合样式 小鱼洞地区 龙门山
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鲜水河断裂带断层间相互作用的触震与缓震效应 被引量:24
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作者 张秋文 张培震 +2 位作者 王乘 汪一鹏 MichaelA.Ellis 《地震学报》 CSCD 北大核心 2003年第2期143-153,228,共11页
探讨了断层间相互作用产生的同震库仑应力改变及对地震的触发与延缓效应,并以鲜水河断裂带不同断裂段时间上连续发生的4次M_s6.0以上地震为例,计算和分析了每次地震发生后,在周围其它断裂上产生的同震库仑应力改变及其对后续地震的触发... 探讨了断层间相互作用产生的同震库仑应力改变及对地震的触发与延缓效应,并以鲜水河断裂带不同断裂段时间上连续发生的4次M_s6.0以上地震为例,计算和分析了每次地震发生后,在周围其它断裂上产生的同震库仑应力改变及其对后续地震的触发,以及1973年炉霍M_s7.6地震和1981年道孚M_s6.9地震发生后,在其周围最易破坏失稳的微破裂上产生的同震库仑应力改变及对余震活动的影响。在其它条件保持不变的情况下,将这4次地震的累积触震与缓震效应加以定量考虑,对鲜水河断裂带各断裂段的地震潜势进行了重新计算,并与已有预测结果进行对比分析,检验和评估了鲜水河断裂带断层间相互作用触震与缓震效应的重要性。结果表明:鲜水河断裂带每次地震都发生于受其先前发生的地震影响而产生同震库仑应力增加的断裂段上,不同断层间相互作用的触震和缓震效应导致地震复发概率的改变可高达30.5%以上,主震后的余震大多发生于同震库仑应力增加较高的微破裂上。 展开更多
关键词 断层 相互作用 触震 缓震效应 地震潜势 鲜水河断裂带
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童年中期同伴关系与孤独感的中介变量检验 被引量:59
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作者 周宗奎 孙晓军 +1 位作者 赵冬梅 Hsueh Yeh 《心理学报》 CSSCI CSCD 北大核心 2005年第6期776-783,共8页
以571名小学三、四、五、六年级的儿童为被试,考察了儿童社会喜好、友谊质量、社交自我知觉与孤独感的关系,检验了社交自我知觉在同伴关系变量与孤独感间的中介作用。结果表明,社会喜好、友谊质量、社交自我知觉和孤独感间相关显著,并... 以571名小学三、四、五、六年级的儿童为被试,考察了儿童社会喜好、友谊质量、社交自我知觉与孤独感的关系,检验了社交自我知觉在同伴关系变量与孤独感间的中介作用。结果表明,社会喜好、友谊质量、社交自我知觉和孤独感间相关显著,并且存在显著的性别差异;社交自我知觉在同伴关系变量与孤独感间存在中介的作用;独立的中介效应检验中,社会喜好、友谊质量均通过社交自我知觉的中介作用与孤独感发生联系,同时,也存在直接的联系;综合模型中,社会喜好只通过社交自我知觉的中介作用与孤独感产生联系,不存在直接效应,而友谊质量与孤独感既存在中介的联系,同时也存在直接联系。 展开更多
关键词 社会喜好 友谊质量 社交自我知觉 孤独感 中介作用
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青藏高原东缘数字高程剖面及其对晚新生代河流下切深度和下切速率的约束 被引量:48
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作者 李勇 A.L.Densmore +3 位作者 周荣军 M.A.Ellis 张毅 黎兵 《第四纪研究》 CAS CSCD 北大核心 2006年第2期236-243,共8页
文章利用数字高程剖面将青藏高原东缘分为4个大尺度地貌单元,即青藏高原地貌区、龙门山高山地貌区、山前冲积平原区(成都盆地)和四川盆地东部隆起区。根据数字高程剖面中的最高海拔高程点剖面与最低海拔高程点剖面之间的高差,定量计算... 文章利用数字高程剖面将青藏高原东缘分为4个大尺度地貌单元,即青藏高原地貌区、龙门山高山地貌区、山前冲积平原区(成都盆地)和四川盆地东部隆起区。根据数字高程剖面中的最高海拔高程点剖面与最低海拔高程点剖面之间的高差,定量计算了该地区河流下切深度;结合成都盆地岷江最古老冲积扇沉积物提供的青藏高原东缘河流形成的时间(3.6M aB.P.),定量计算了河流下切速率为1.29mm/a;在约束局部侵蚀基准面和气候变化对河流下切速率控制作用的基础上,建立了青藏高原东缘河流下切速率与表面隆升速率之间的定量关系,结果表明河流下切速率约为表面隆升速率的4倍。基于龙门山在表面隆升速率和下切速率等方面均大于青藏高原内部,认为青藏高原东缘的边缘山脉是剥蚀隆升和构造隆升两者叠加的产物。 展开更多
关键词 青藏高原东缘 数字高程剖面 河流下切深度 河流下切速率 表面隆升速率
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