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Congenital left ventricular aneurysms and diverticula： an entity in search of an identity

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Journal of Geriatric Cardiology 2017年第12期14卷 750-762页

作者： marc.Alexander Ohlow Heart Center Department of Cardiology Zentralklinik Bad Berka Germany

Congenital left ventricular aneurysm or diverticulum are rare cardiac malformations described in 809 cases since the first description in 1816, being associated with other cardiac, vascular or thoraco-abdominal abnormalities in about 70%. It appears to be a developmental anomaly, starting in the 4th embryonic week. In an experimental study, targeted knockdown of cardiac troponin T in the chick was performed at day 3, after the heart tube has formed. Morpholino treatment of gene TNNT2 at this stage led to the development of left ventricular diver- ticula （LVD） in the primitive left ventricular wall. Diagnosis of left ventricular aneurysms （LVA）/LVD can be made after exclusion of coro- nary artery disease, local or systemic inflammation or traumatic causes as well as cardiomyopathies. Clinically, most of LVA and LVD are asymptomatic or may cause systemic embolization, congestive heart failure, valvular regurgitation, ventricular wall rupture, ventricular tachycardia or sudden cardiac death. Diagnosis is established by imaging studies （echocardiography, magnetic resonance imaging or left ventricular angiography） visualizing the structural changes and accompanying abnormalities. Mode of treatment has to be individually tai- lored and depends on clinical presentation, accompanying abnormalities and possible complications, options include surgical resection （espe- cially in symptomatic patients）, anticoagulation after systemic embolization, radiofrequency ablation or implantation of an implantable car- dioverter defibrillator （ICD） in case of symptomatic ventricular tachycardias, and occasionally combined with class I- or III-antiarrhythmic drugs. Cardiac death occurs usually in childhood, is significantly more frequent in LVA patients and caused by congestive heart failure in most of the cases, whereas patients diagnosed with LVD died more frequently from rupture of the LVD.

关键词： Aneurysm Congenital Diverticulum Left ventricular Prognosis Therapy

Global significance of oxygen and carbon isotope compositions of pedogenic carbonates since the Cretaceous

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Geoscience Frontiers 2021年第4期12卷 34-45页

作者： marc.Jolivet Philippe Boulvais Géosciences Rennes CNRSUniv RennesUMR 6118F-35000RennesFrance

Few global syntheses of oxygen and carbon isotope composition of pedogenic carbonates have been attempted,unlike marine *** carbonates represent in-situ indicators of the climate conditions prevailing on *** δ^(18)O and δ^(13)C values of pedogenic carbonates are controlled by local and global factors,many of them not affecting the marine carbonates largely used to probe global climate *** compile pedogenic oxygen and carbon isotopic data(N=12,167)fromCretaceous to Quaternary-aged paleosols to identify potential trends through time and tie them to possible controlling *** discrete events such as the Paleocene-Eocene Thermal Maximum are clearly evidenced,our analysis reveals an increasing complexity in the distribution of the δ^(18)O vs δ^(13)C values through the *** could be expected,the rise of C4 plants induces a shift towards higherδ13C values during the Neogene and *** also show that the increase in global hypsometry during the Neogene plays a major role in controlling the δ^(18)O and δ^(13)C values of pedogenic carbonates by increasing aridity downwind of orographic ***,during the Quaternary,an increase of 3‰in δ^(18)O values is recorded both by the pedogenic carbonates and the marine foraminifera suggesting that both indicators may be used to track global climate signal.

关键词： Global isotopic signal Cretaceous–Quaternary Pedogenic carbonates Topography

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布拉茨克工程静力与渗流相关计算

水利水电快报 1993年第19期14卷 2-4页

作者： marc.,AN 车新觉

A FAST FREE MEMORY METHOD FOR AN EFFICIENT COMPUTATION OF CONVOLUTION KERNELS

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Journal of Computational Mathematics 2023年第6期41卷 1093-1116页

作者： Matthieu Aussal marc.Bakry Ecole Polytechnique(CMAP) INRIAInstitut Polytechnique ParisRoute de Saclay 91128PalaiseauFrance

We introduce the Fast Free Memory method(FFM),a new implementation of the Fast Multipole Method(FMM)for the evaluation of convolution *** FFM aims at being easier to implement while maintaining a high level of performance,capable of handling industrially-sized *** FFM avoids the implementation of a recursive tree and is a kernel independent *** give the algorithm and the relevant complexity *** quasi-linear complexity enables the evaluation of convolution products with up to one billion *** illustrate numerically the capacities of the FFM by solving Boundary Integral Equations problems featuring dozen of millions of *** implementation is made freely available under the GPL 3.0 license within the Gypsilab framework.

关键词： Convolution product Fast multipole method Boundary integral equations Open-source

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新井控系统的设计,结构和操作

国外钻井技术 1995年第3期10卷 61-63,47页

作者： marc.,CR 许炳瑞

Leibniz seminorms and best approximation from C*-subalgebras

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Science China Mathematics 2011年第11期54卷 2259-2274页

作者： RIEFFEL marc.A Department of Mathematics University of CaliforniaBerkeleyCA 94720-3840USA

We show that if B is a C*-subalgebra of a C*-algebra A such that B contains a bounded approximate identity for A,and if L is the pull-back to A of the quotient norm on A/B,then L is strongly *** connection with this situation we study certain aspects of best approximation of elements of a unital C*-algebra by elements of a unital C*-subalgebra.

关键词： C^*-subalgebras best approximation distance formula Leibniz inequality strongly-Leibniz minimal elements

Deep inside molecules-digital twins at the nanoscale

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Virtual Reality & Intelligent Hardware 2022年第4期4卷 324-341页

作者： marc.BAADEN CNRS Universitéde ParisUPR 9080Laboratoire de Biochimie Théorique13 rue Pierre et Marie CurieF-75005ParisFrance Institut de Biologie Physico-Chimique-Fondation Edmond de Rothschild ParisFrance

Background Digital twins offer rich potential for exploration in virtual reality(VR).Using interactive molecular simulation approaches,they enable a human operator to access the physical properties of molecular objects and to build,manipulate,and study their *** modeling and drug design are important applications of this *** In this study,head-mounted virtual reality displays connected to mole-cular simulation engines were used to create interactive and immersive digital *** were used to perform tasks relevant to specific use *** Three areas were investigated,including model building,rational design,and tangible ***,we report several membrane-embedded systems of ion channels,viral com-ponents,and artificial water *** were able to improve and create molecular designs based on digital *** The molecular application domain offers great opportunities,and most of the technical and tech-nological aspects have been *** adoption is expected once the onboarding of VR is simplified and the technology gains wider acceptance.

关键词： Digital twins Molecular simulation Virtual reality

A Fast Ambient Occlusion Method for Real-Time Plant Rendering

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Journal of Computer Science & Technology 2007年第6期22卷 859-866页

作者：滕军 marc.Jaeger 胡包钢 LIAMA/NLPR Institute of AutomationChinese Academy of Sciences INRIA-Futurs DigiPlante TeamCIRAD AMAPMontpellierFrance

Global illumination effects are crucial for virtual plant rendering. Whereas real-time global illumination rendering of plants is impractical, ambient occlusion is an efficient alternative approximation. A tree model with millions of triangles is common, and the triangles can be considered as randomly distributed. The existing ambient occlusion methods fail to apply on such a type of object. In this paper, we present a new ambient occlusion method dedicated to real time plant rendering with limited user interaction. This method is a three-step ambient occlusion calculation framework which is suitable for a huge number of geometry objects distributed randomly in space. The complexity of the proposed algorithm is O（n）, compared to the conventional methods with complexities of O（n^2）. Furthermore, parameters in this method can be easily adjusted to achieve flexible ambient occlusion effects. With this ambient occlusion calculation method, we can manipulate plant models with millions of organs, as well as geometry objects with large number of randomly distributed components with affordable time, and with perceptual quality comparable to the previous ambient occlusion methods.

关键词： accessibility value estimation plant visualization real-time rendering

Parametric simulation of electron backscatter diffraction patterns through generative models

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npj Computational Materials 2023年第1期9卷 285-294页

作者： Zihao Ding marc.De Graef Department of Materials Science and Engineering Carnegie Mellon UniversityPittsburghPA 15213USA

Recently,discriminative machine learning models have been widely used to predict various attributes from Electron Backscatter Diffraction(EBSD)***,there has never been any generative model developed for EBSD pattern *** one hand,the training of generative models is much harder than that of discriminative ones;On the other hand,numerous variables affecting EBSD pattern formation make the input space high-dimensional and its relationship with the distribution of backscattered electrons *** this study,we propose a framework(EBSD-CVAE/GAN)with great flexibility and scalability to realize parametric simulation of EBSD *** with the frequently used forward model,EBSD-CVAE/GAN can take variables more than just orientation and generate corresponding EBSD patterns in a single *** accuracy and quality of generated patterns are systematically *** model does not only summarize a distribution of backscattered electrons at a higher level,but also mitigates data scarcity in this field.

关键词： EBSD distribution pattern