检索结果-南通市图书馆

[^(18)F]MAGL-4-11 positron emission tomography molecular imaging of monoacylglycerol lipase changes in preclinical liver fibrosis models

引用

Acta Pharmaceutica Sinica B 2022年第1期12卷 308-315页

作者： Tuo Shao Zhen Chen Jian Rong Vasily Belov Jiahui Chen Andre Jeyarajan Xiaoyun Deng hualong Fu Qingzhen Yu steve h.rwema Wenyu Lin Mikhail Papisov Lee Josephson Raymond T.Chung steven h.Liang Division of Nuclear Medicine and Molecular Imaging Department of RadiologyMassachusetts General Hospital and Harvard Medical SchoolBostonmA 02114USA Liver Center and Gastrointestinal Division Department of MedicineMassachusetts General HospitalHarvard Medical SchoolBostonA 02114USA Shriners hospitals for Children-Boston Boston BostonMA 02114USA

Monoacylglycerol lipase(MAGL) is a pivotal enzyme in the endocannabinoid system, which metabolizes 2-arachidonoylglycerol(2-AG) into the proinflammatory eicosanoid precursor arachidonic acid(AA). MAGL and other endogenous cannabinoid(EC) degrading enzymes are involved in the fibrogenic signaling pathways that induce hepatic stellate cell(hSC) activation and ECM accumulation during chronic liver disease. Our group recently developed an;F-labeled MAGL inhibitor([18F]MAGL-4-11)for PET imaging and demonstrated highly specific binding in vitro and in vivo. In this study, we determined [18F]MAGL-4-11 PET enabled imaging MAGL levels in the bile duct ligation(BDL) and carbon tetrachloride(CCl_(4)) models of liver cirrhosis;we also assessed the hepatic gene expression of the enzymes involved with EC system including MAGL, NAPE-PLD, FAAh and DAGL that as a function of disease severity in these models;[18F]MAGL-4-11 autoradiography was performed to assess tracer binding in frozen liver sections both in animal and human. [18F]MAGL-4-11 demonstrated reduced PET signals in early stages of fibrosis and further significantly decreased with disease progression compared with control mice. We confirmed MAGL and FAAh expression decreases with fibrosisseverity, while its levels in normal liver tissue are high;in contrast, the EC synthetic enzymes NAPE-PLD and DAGL are enhanced in these different fibrosis models. In vitro autoradiography further supported that[18F]MAGL-4-11 bound specifically to MAGL in both animal and human fibrotic liver tissues. Our PET ligand [18F]MAGL-4-11 shows excellent sensitivity and specificity for MAGL visualization in vivo and accurately reflects the histological stages of liver fibrosis in preclinical models and human liver tissues.

关键词： [18F]MAGL-4-11 PET imaging Liver fibrosis MAGL

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Formulation and procedure for in situ stress back-analysis from borehole strain changes measured during nearby underground excavation

引用

Journal of Rock Mechanics and Geotechnical Engineering 2023年第8期15卷 1931-1943页

作者： Cui Lin D.h.steve Zou Mineral Resource Engineering Dalhousie UniversityHalifaxCanada

Estimation of in situ stresses based on back-analysis of measured stress changes and displacements has become an alternative to the direct stress measurement *** order to help users conduct own measurement and analysis,this paper presents in detail a field stress back-analysis approach directly from borehole strain changes measured during nearby underground *** formulations in major steps and the procedure for the entire analysis process are provided to allow users to *** instrument for borehole strain change measurement can be the CSIR or CSIRO stress cells and other borehole strain cells that can measure strains on borehole *** changes corresponding to the stress changes at a borehole location are calculated in borehole *** stress changes due to nearby excavation can be calculated by an analytical model for a single circular opening and simulated by a numerical model for non-circular and multiple *** models are based on isotropic,homogeneous and linear elastic *** analysis of borehole strain changes is accomplished by multiple linear regression based on error minimization and an integrated process provides the best-fit solution directly to the in situ stresses.A statistical technique is adopted for screening outliers in the measurement data,checking measurement compatibility and evaluating the reliability of analysis *** application example is included to demonstrate the practical application and the analysis procedure.

关键词： In situ stress field Back-analysis Borehole strain change Multiple linear regression Underground excavation Data compatibility Result reliability

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Digital neuromorphic technology: current and future prospects

引用

National Science Review 2024年第5期11卷 10-11页

作者： steve Furber Department of Computer Science The University of Manchester

Neuromorphic technology has diversified considerably from its origins in the seminal work by Carver Mead and his group at Caltech in the 1980s [1]. That early work focussed on the analogy between the equations describing the flow of ions in biological neurons and the equations describing the flow of carriers in field-effect transistors operating in the subthreshold region.

关键词： technology current future digital neuromorphic prospects

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Guest editorial: Machine Learning in Wireless Networks

引用

CAAI Transactions on Intelligence Technology 2021年第2期6卷 133-134页

作者： Anil Kumar Budati steve S.h.Ling Department of Electronics and Communication Engineering Gokaraju Rangaraju Institute of Engineering and TechnologyHyderabadIndia School of Biomedical Engineering University of Technology SydneySydneyNew South WalesAustralia

This dedicated Special Section on Machine Learning in Wireless Networks aims to provide improved knowledge for state-of-the-art worldwide R&D communities in wireless networks and machine learning(ML)*** aims to do so by calling for novel formulations,innovative techniques,and optimised solutions to highlight the key issues related to these problems in a forum for shared research and ideas.

关键词： Wireless wireless formulation

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Modern Black Sea oceanography applied to the end-Permian extinction event

引用

Journal of Palaeogeography 2015年第1期4卷 52-62页

作者： steve Kershaw Institute for the Environment Health and Societies Brunel UniversityKingston LaneUxbridge Middlesex UB8 3PH UK

The modern Black Sea has a mixed upper layer in the top 150-200 m of the water column, below which the water is anoxic, separated from the mixed layer by a redox boundary. There is limited vertical movement of water. Pyrite framboids form in the water column of the anoxic zone, then have been traditionally interpreted to sink immediately and accumulate in the sediments of the Black Sea. Thus the occurrence of framboids in sediments in the rock record is widely interpreted to indicate poorly oxygenated to anoxic conditions in ancient environments. however, in the Permian-Triassic boundary （PTB） microbialites of South China, which formed in shallow marine conditions in contact with the atmosphere, the published occurrence of framboids is inconsistent with abundant gastropod and ostracod shells in the microbialite. Furthermore, in the modern Black Sea, （a） framboids may be suspended, attached to organic matter in the water column, thus not settle to the sea floor immediately after formation; and （b） the redox zone is an unstable complex area subject to rapid vertical water movement including occasional upwelling. The model presented here supposes that upwelling through the redox zone can lead to upward transport of suspended pyrite framboids into the mixed layer. Advective circulation could then draw suspended framboids onto the shelf to be deposited in oxygenated sediments. In the Permian-Triassic transition, if framboids were upwelled from below the redox boundary and mixed with oxygenated waters, sediment deposited in these conditions could provide a mixed signal for potentially misleading interpretations of low oxygen conditions. however, stratigraphic sampling resolution of post-extinction microbialites is currently insufficient to demonstrate possible separation of framboid-bearing layers from those where framboids are absent. Profound differences between microbialite constructors and sequences between the western and eastern Tethys demonstrate barriers to migra

关键词： mass extinction Permian-Triassic boundary microbialite ostracods gastro-pods anoxia Black Sea

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Improving reflectance estimation by BRDF-consistent region clustering

引用

Progress in Natural Science:Materials International 2006年第3期16卷 313-320页

作者： LIN steve Beijing 100080 China Visual Computing Group Microsoft Research Asia

Previous studies in reflectance estimation generally require prior segmentation of an image into regions of uniform reflectance. Due to the measurement noise and limited sampling of the BRDF (bi-directional reflectance function) directions, such estimated results of reflectance are not accurate. In this paper, we propose a novel method for reducing uncertainty in reflectance estimates by merging image regions which have consistent reflectance observations. Each image region acts as a reflectance subspace, so merging of the image regions can result in subspace reduction. We propose a Bayesian segmentation framework to decrease the reflectance uncertainty by using novel merging criteria. Finally, a maximum likelihood reflectance estimation is made for each resulting image region. Experimental results verify the feasibility and superiority of this reflectance-oriented region merging method.

关键词： texture shading grouping and segmentation reflectance estimation BRDF uncertainty.

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Quantitative Absolute Continuity of harmonic Measure and the Dirichlet Problem: A Survey of Recent Progress

引用

Acta Mathematica Sinica,English Series 2019年第6期35卷 1011-1026页

作者： steve hOFMANN Department of Mathematics University of Missouri

It is a well-known folklore result that quantitative, scale invariant absolute continuity(more precisely, the weak-A∞ property) of harmonic measure with respect to surface measure, on the boundary of an open set Ω ? R^(n+1) with Ahlfors–David regular boundary, is equivalent to the solvability of the Dirichlet problem in Ω, with data in L^p (?Ω) for some p he famous Wiener criterion, which characterizes the domains in which the classical Dirichlet problem, with continuous boundary data, can be solved, one may seek to characterize the open sets for which L^psolvability holds, thus allowing for singular boundary *** has been known for some time that absolute continuity of harmonic measure is closely tied to rectifiability properties of ?Ω, but also that rectifiability alone is not sufficient to guarantee absolute continuity. In this note, we survey recent progress in this area, culminating in a geometric characterization of the weak-A∞ property, and hence of solvability of the L^p Dirichlet problem for some finite p. This characterization, obtained under rather optimal background hypotheses, follows from a combination of the present author's joint work with Martell, and the work of Azzam, Mourgoglou and Tolsa.

关键词： harmonic measure Poisson kernel uniform rectifiability weak local John condition big pieces of chord-arc domains Carleson measures

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Underground mine stream crossing assessment:A multi-disciplinary approach

引用

International Journal of Mining Science and Technology 2021年第1期31卷 59-65页

作者： Kevin Andrews steve Keim Marshall Miller&Associates BluefieldVA 24605USA

Underground mine designs typically try to avoid extraction beneath streams and rivers of any significant size,especially when the overburden rock thickness between the stream bed and the mine is *** issues with mining beneath streams include excessive groundwater inflow to the mine,weak ground(roof,floor,and pillar)conditions,horizontal stress effects,as well as stream loss and other potential adverse environmental ***,there are times when crossing beneath a stream or river is necessary to move into a new area of mineral reserve without creating additional mine access points from the ground ***,stream crossings are completed without thorough assessment,potentially resulting in increased costs,decreased safety,and,in some cases,failure to advance the *** of the most favorable location(s)to cross the stream must account for numerous factors and the associated assessment often requires a multi-disciplinary *** crossing investigations often require geological,hydrogeological,geotechnical,and geophysical *** of stream crossing investigations include desktop evaluation of maps and aerial photography,stream bed observations,drilling,detailed rock core logging,downhole geophysical surveying,hydraulic conductivity testing(packer testing),geotechnical laboratory testing,assessment,and *** deliverables from a stream crossing assessment typically include geological,geotechnical,and hydrogeological characterization of potential stream crossing locations,classification of favorable and unfavorable crossing locations,recommendations for entry design and pillar sizing,and recommendations for if,and how,to conduct pre-grouting *** of technical aspects of data collection and assessment are provided based on decades of industry experience conducting stream crossing assessments in various underground mining scenarios.

关键词： Underground mining Geotechnical Stream-crossing hydrogeology Characterization

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Green spermatozoa illuminate a 30-year-old model： sperm-egg adhesion involves intra-acrosomal proteins

引用

Asian Journal of Andrology 2011年第5期13卷 665-666页

作者： steve Tardif Reproductive and Developmental Biology Group Centrefor Oncology and Molecular Medicine Division ofMedical Sciences Ninewells Hospital University ofDundee Dundee Scotland DD1 9SY UK

Fertilisation in mammals involves many synchronized steps including spermegg adhesion. Prior to sperm-oolemma fusion, spermatozoa need to undergo the acrosome reaction （AR） or exocytosis. The universal belief, for many years, has been that the AR was initiated upon binding to the zona pellucida （ZP）. As such acrosomal proteins were not thought to be involved in the primary contact with the ZP. These proteins were only suggested to be biologically relevant once the sperm were attached to the ZP and during subsequent events. however,

关键词： Green reexamination

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

A strategy for rock/coal outburst prevention

引用

Journal of Coal Science & Engineering(China) 2007年第3期13卷 225-229页

作者： D.h. steve Zou 程久龙 Mineral Resource Engineering Dalhousie University Halifax B3J1Z1 Key Laboratory of Mine Disaster Prevention and Control Shandong University of Science ＆ Technology Qingdao 266510 China

The current practice of rock/coal outburst monitoring, prevention and control was reviewed. The uncertainty of major factors contributing to the occurrence of such hazards and the complexicity of mining conditions surrounding the occurrence were analyzed. A strategic concept for rock/coal outburst prevention was introduced. The objective is to identify the bursting potential in an area, rather than predicting the bursting, by introducing a multi- dimension index model： potential-of-bursting （POB）, taking into consideration major contributing factors. In application, once the index has passed certain critical level indicating high risk, actions must be taken to reduce the bursting potential and to effectively prevent the hazard from occurring. A conceptual 2D model involving stress and methane pressure was described to demonstrate the methodology for determining the POB. however in practice, a POB model has to be established through experiments, field monitoring and calibration against case studies. To achieve this objective, coordinated research and international collaboration will be needed.

关键词： rock/coal outbursts mine hazards bursting potential

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：