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Up to 70 THz bandwidth from an implanted Ge photoconductive antenna excited by a femtosecond Er:fibre laser

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Light(Science & Applications) 2020年第1期9卷 1716-1722页

作者： Abhishek Singh Alexej Pashkin Stephan Winnerl Malte Welsch Cornelius Beckh Philipp Sulzer Alfred Leitenstorfer Manfred Helm harald schneider Institute of Ion Beam Physics and Materials Research Helmholtz-Zentrum Dresden-Rossendorf01328 DresdenGermany Cfaed and Institute of Applied Physics TU Dresden01062 DresdenGermany Department of Physics and Center for Applied Photonics University of Konstanz78457 KonstanzGermany

Phase-stable electromagnetic pulses in the THz frequency range offer several unique capabilities in time-resolved ***,the diversity of their application is limited by the covered spectral *** particular,the upper frequency limit of photoconductive emitters-the most widespread technique in THz spectroscopy-reaches only up to 7 THz in the regular transmission mode due to absorption by infrared-active optical ***,we present ultrabroadband(extending up to 70 THz)THz emission from an Au-implanted Ge emitter that is compatible with mode-locked fibre lasers operating at wavelengths of 1.1 and 1.55μm with pulse repetition rates of 10 and 20 MHz,*** result opens up the possibility for the development of compact THz photonic devices operating up to multi-THz frequencies that are compatible with Si CMOS technology.

关键词： antenna emitter fibre

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江苏铁角蕨的系统位置和多倍体起源

植物分类与资源学报 2014年第1期36卷 7-12页

作者：常艳芬李捷陆树刚 harald schneider 中国科学院西双版纳热带植物园植物系统发育与保护生物学实验室云南昆明650223 中国科学院大学北京100049 云南大学生态学与地植物学研究所云南昆明650091 Botany Department Natural History Museum

运用分子系统发育分析的方法研究了江苏铁角蕨(Asplenium kiangsuense)的系统位置及其与庐山铁角蕨(***)的关系,并探讨了该类群可能的多倍体起源方式。结果显示:江苏铁角蕨与庐山铁角蕨可能为同源四倍体,是组成倒挂铁角蕨复合体(*** com... 详细信息

运用分子系统发育分析的方法研究了江苏铁角蕨(Asplenium kiangsuense)的系统位置及其与庐山铁角蕨(***)的关系,并探讨了该类群可能的多倍体起源方式。结果显示:江苏铁角蕨与庐山铁角蕨可能为同源四倍体,是组成倒挂铁角蕨复合体(*** complex)的成员之一;二者在形态特征与基因序列方面均表现一致,接受英文版中国植物志的处理,即把庐山铁角蕨处理为江苏铁角蕨的异名。

关键词：江苏铁角蕨庐山铁角蕨核基因pgiC 叶绿体基因系统位置多倍体起源

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云南南部地区蕨类植物多样性与地理分布

绿色科技 2021年第17期23卷 120-125页

作者：陈柯 Phyo Kay Khine harald schneider 中国科学院西双版纳热带植物园综合保护中心云南勐腊666303 中国科学院大学北京100049

以云南南部地区的蕨类植物为研究对象,数字化的标本记录为数据来源,对蕨类植物的物种组成情况进行了统计分析,对蕨类植物多样性的空间分布格局进行了可视化展示,并结合环境数据探讨了蕨类植物多样性与环境变量之间的关系。结果表明:云... 详细信息

以云南南部地区的蕨类植物为研究对象,数字化的标本记录为数据来源,对蕨类植物的物种组成情况进行了统计分析,对蕨类植物多样性的空间分布格局进行了可视化展示,并结合环境数据探讨了蕨类植物多样性与环境变量之间的关系。结果表明:云南南部地区蕨类植物的多样性水平较高,物种组成丰富。云南南部地区共有蕨类植物37科116属690种,占云南蕨类植物总种数的52.6%。云南南部地区蕨类植物的物种丰富度与系统发育多样性、物种β多样性与系统发育β多样性均有显著的正相关,空间分布格局相似。云南南部地区蕨类植物的物种丰富度和系统发育多样性与环境变量中的气候变量相关性较强,而与地形变量的相关性较弱。云南南部地区蕨类植物的物种β多样性、系统发育β多样性与地理距离和环境距离都有显著的相关性,表明扩散限制和环境过滤过程对云南南部地区蕨类植物物种β多样性和系统发育β多样性的形成都有重要的作用。

关键词：蕨类植物物种丰富度系统发育多样性 β多样性

APPROXIMATING THE STATIONARY BELLMAN EQUATION BY HIERARCHICAL TENSOR PRODUCTS

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Journal of Computational Mathematics 2024年第3期42卷 638-661页

作者： Mathias Oster Leon Sallandt Reinhold schneider Technische Universität Berlin Strasse des 17.Juni 13510623 BerlinGermany

We treat infinite horizon optimal control problems by solving the associated stationary Bellman equation numerically to compute the value function and an optimal feedback *** dynamical systems under consideration are spatial discretizations of non linear parabolic partial differential equations(PDE),which means that the Bellman equation suffers from the curse of *** non linearity is handled by the Policy Iteration algorithm,where the problem is reduced to a sequence of linear equations,which remain the computational bottleneck due to their high *** reformulate the linearized Bellman equations via the Koopman operator into an operator equation,that is solved using a minimal residual *** the Koopman operator we identify a preconditioner for operator equation,which deems essential in our numerical *** overcome computational infeasability we use low rank hierarchical tensor product approximation/tree-based tensor formats,in particular tensor trains(TT tensors)and multi-polynomials,together with high-dimensional quadrature,*** controlling a destabilized version of viscous Burgers and a diffusion equation with unstable reaction term numerical evidence is given.

关键词： Feedback control Dynamic programming Hamilton-Jacobi-Bellman Tensor product approximation Variational Monte-Carlo

Modeling displacement flow inside a full-length casing string for well cementing

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Petroleum Research 2024年第1期9卷 1-16页

作者： Hu Dai Ali Eslami Jason schneider Gefei Liu Fred Schwering Pegasus Vertex Inc.USA Laval University Canada Sanjel Energy Services Canada Athabasca Oil Corporation Canada

While computer modeling of annular displacement efficiency is widely applied in cementing engineering,modeling the displacement flow inside a casing or drill string for cementing operations has received less *** predicting displacement efficiency inside a full-length pipe is desired by cementing engineers,the attempt of developing a model with both efficiency and accuracy faces *** to computer simulators for this purpose is *** with annular flow,the displacement flow inside pipe,although within a simpler geometry and without eccentricity effect,is not simpler in physics,modelling strategy and predictability,because a variety of flow patterns and flow instabilities can develop to create complicated fluid *** this paper,we present an integrated numerical model developed to simulate displacement flows inside a full-length pipe,which connects an existing annulus model to enable complete displacement simulations of cementing *** model uses three-dimensional grid to solve fluid concentrations with degrees of mixing,and incorporates flow instability detection and flow regime *** in cementing,the model accounts for effects of pumping rate,well inclination,pipe rotation,fluid densities,rheological parameters and *** computationally efficient model does not rely on high-resolution mesh as often required by conventional Computational Fluid Dynamics models,thus it is suitable to be implemented in a cementing software for daily use by well cementing *** methodology of the model is discussed in detail in this *** validate the model,we examine simulation results against experimental results obtained in our laboratory tests and CFD simulations;acceptable agreement is found under different testing *** also presented two case studies of real cementing jobs with cement evaluation logs compared to simulation results,showing that the model can predict consistent displacement efficie

关键词： Inside pipe displacement Displacement efficiency Numerical model Primary cementing Displacement flow

Two-photon emission from a superlattice-based superconducting light-emitting structure

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Light(Science & Applications) 2024年第7期13卷 1331-1340页

作者： Shlomi Bouscher Dmitry Panna Ronen Jacovi Fauzia Jabeen Christian schneider Sven Höfling Alex Hayat Department of Electrical Engineering TechnionHaifa 32000Israel. Technische Physik Universität WürzburgAm HublandD-97074 WürzburgGermany. Institute of Physics Carl von Ossietzky Universität OldenburgD-26111 OldenburgGermany

Superconductor-semiconductor hybrid devices can bridge the gap between solid-state-based and photonics-based quantum systems,enabling new hybrid computing schemes,offering increased scalability and *** example for a hybrid device is the superconducting light-emitting diode(SLED).SLEDs have been theoretically shown to emit polarization-entangled photon pairs by utilizing radiative recombination of Cooper ***,the twophoton nature of the emission has not been shown experimentally *** demonstrate two-photon emission in a GaAs/AlGaAs *** electroluminescence spectra reveal unique two-photon superconducting features below the critical temperature(Tc),while temperature-dependent photon-pair correlation experiments(g(2)(τ,T))demonstrate temperature-dependent time coincidences below Tc between photons emitted from the *** results pave the way for compact and efficient superconducting quantum light sources and open new directions in light-matter interaction studies.

关键词： photon quantum utilizing

Femoral Access with Ultrasound-Guided Puncture and Z-Stitch Hemostasis for Adults with Congenital Heart Diseases Undergoing Electrophysiological Procedures

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Congenital Heart Disease 2024年第1期19卷 85-92页

作者： Fu Guan Matthias Gass Florian Berger Heiko schneider Firat Duru Thomas Wolber Arrhythmia and Electrophysiology Division Department of CardiologyUniversity Heart Center ZurichZurichSwitzerland Children’s Research Center Zurich University Children’s HospitalZurichSwitzerland Center for Integrative Human Physiology University of ZurichZurichSwitzerland

Aims:Although the application of ultrasound-guided vascular puncture and Z-stitch hemostasis to manage femoral access has been widely utilized,there is limited data on this combined application in adult congenital heart disease(ACHD)patients undergoing electrophysiological(EP)*** sought to evaluate the safety and efﬁcacy of ultrasound-guided puncture and postprocedural Z-stitch hemostasis for ACHD patients under-going EP *** and Results:The population of ACHD patients undergoing transfemoral EP pro-cedures at the University of Zurich Heart Center between January 2019 and December 2022 was observed and *** the study period,femoral access(left/right,arterial/venous)was performed under real-time ultrasound *** the end of the procedure,a single Z-stitch was performed at the puncture *** eval-uated the incidence of in-hospital complications associated with femoral access puncture in this *** 101 patients who had a total of 147 previous ipsilateral vascular punctures(mean 1.5 per person),100 patients underwent successful femoral vascular access for EP *** median age of the patients was 47±15 years and 34(34%)were male.Z-stitches were performed after the procedure in 100 patients with 303 femoral vascular accesses(mean 3 punctures per person).No patient developed vascular puncture relevant inguinal hematoma,pseudo aneurysm,arteriovenousﬁstula,venous or arterial ***:In ACHD patients undergoing EP procedures,optimal femoral access management can be achieved with ultra-sound-guided puncture and postprocedural Z-stitch hemostasis.

关键词： Congenital heart disease cardiac electrophysiology cardiac catheterization femoral access hemostasis

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缅甸白垩纪琥珀苔类植物系统分类与多样性

缅甸白垩纪琥珀苔类植物系统分类与多样性

Emerging and multifaceted potential contributions of polyphenols in the management of type 2 diabetes mellitus

中国古生物学会古植物学分会、江苏省古生物学会2021年学术年会

作者：李亚王永栋李丽琴 Kathrin Feldberg 吴鹏程 harald schneider 中国科学院南京地质古生物研究所 University of G?ttingen 中国科学院植物研究所中国科学院西双版纳热带植物园

白垩纪陆地革命(Cretaceous Terrestrial Revolution,125～80 Ma)是一个重要的生物演化事件,在此期间陆地上的生物多样性首次超过海洋中的生物多样性,与此同时被子植物迅速大量出现,并驱动附生苔类、藓类、石松类和水龙骨类的多样性演... 详细信息

白垩纪陆地革命(Cretaceous Terrestrial Revolution,125～80 Ma)是一个重要的生物演化事件,在此期间陆地上的生物多样性首次超过海洋中的生物多样性,与此同时被子植物迅速大量出现,并驱动附生苔类、藓类、石松类和水龙骨类的多样性演化。分子系统学研究显示以光萼苔目(Porellales)为代表的附生苔类在白垩纪陆地革命时期多样化速率突然增加,而以叶苔目(Jungermanniales)为代表的一般习性的苔类多样化速率基本不变。缅甸白垩纪琥珀中的苔类化石距今(98.79±0.62) Ma,时间上刚好处于白垩纪陆地革命时期,为我们认识这一时期的苔类的多样性演化历史打开了一扇重要的时空窗口。缅甸克钦邦琥珀中发现的苔类化石均属于光萼苔目,迄今为止报道有3科4属7种,已显示出一定程度的多样性。德国慕尼黑大学Jochen Heinrichs教授带领的团队近年来在缅甸琥珀中发现和描述了6个新种,包括耳叶苔科(Frullaniaceae)的Frullaniabaerlocheri,***,***,Protofrullaniacornigera,多囊苔科(Lepidolaenaceae)的Gackstroemiacretacea以及扁萼苔科(Radulaceae)的Radula cretacea,并对Hentschel et al.2009年发表的***进行了一次修订。此外,我们2020年在Cretaceous Research上报道了一块保存有解剖构造的耳叶苔科(Frullaniaceae)营养枝琥珀化石,并建立了深裂耳叶苔新种(*** ***.)。缅甸琥珀中的苔类通常为配子体营养枝碎片,很少有繁殖结构,尤其是完整的配子体非常稀少。值得指出的是,***和***分别根据分散保存的苔类配子体的幼嫩雌苞和营养枝而建立,但两者的形态特征暗示它们可能亲缘关系较近或者属于同一种植物的不同部位。我们今年在Cretaceous Research上首次报道了一块完整的耳叶苔科配子体琥珀化石,营养枝与雌苞连生。该化石的雌苞叶显示出背瓣顶端具细尖,腹瓣扁平,小苞片顶部二浅裂等特征,与***的特征一致;而营养枝具有羽状分枝和小叶分支,侧叶腹瓣囊状、距茎远且腹叶全缘等特征,与***的特征一致。据此,我们认为***和***应属于同一种植物。鉴于后者发表较晚,应属于晚出异名。缅甸琥珀中有些类型的苔类比较独特,如耳叶苔科(Frullaniaceae)的***。该种具有带状的腹叶,假根着生在腹叶顶部。而耳叶苔科的其他现生种和化石种的腹叶均非带状,假根着生在腹叶中部或下部。因此该化石很可能是耳叶苔科内的一个干群分子。除了***以外,缅甸琥珀中的苔类均可以归入现代属之中,形态上与现生苔类非常相似。Radula cretacea甚至可以确切地归入到扁萼苔属Odontoradula亚属。这种情形可能表明这些附生苔类具有强烈的形态学停滞性(morphological stasis)。然而茎叶体苔类中的异源同形(morphological homoplasy)和隐形成种(cryptic speciation)也经常存在。因此,白垩纪缅甸琥珀中的苔类化石与现生苔类之间形态相似性也可能是这两种因素产生的。

关键词：白垩纪缅甸琥珀苔类光萼苔目多样性

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World Journal of Diabetes 2024年第2期15卷 154-169页

作者： Ileana González Cristian Lindner Ivan schneider Erik Diaz Miguel Angel Morales Armando Rojas Biomedical Research Laboratories Faculty of MedicineCatholic University of MauleTalca 34600000Chile Department of Radiology Faculty of MedicineUniversity of ConcepciónConcepción 4030000Chile Centre of Primary Attention South Metropolitan Health ServiceSantiago 3830000Chile Faculty of Medicine Catholic University of MauleTalca 3460000Chile Molecular and Clinical Pharmacology Program Institute of Biomedical SciencesUniversity of ChileSantiago 8320000Chile

Type 2 diabetes mellitus(T2DM)is recognized as a serious public health concern with a considerable impact on human life,long-term health expenditures,and substantial health *** this context,the use of dietary polyphenols to prevent and manage T2DM is widely *** dietary compounds exert their beneficial effects through several actions,including the protection of pancreatic islet β-cell,the antioxidant capacities of these molecules,their effects on insulin secretion and actions,the regulation of intestinal microbiota,and their contribution to ameliorate diabetic complications,particularly those of vascular *** the present review,we intend to highlight these multifaceted actions and the molecular mechanisms by which these plant-derived secondary metabolites exert their beneficial effects on type 2 diabetes patients.

关键词： Polyphenols Antioxidants Oxidative stress Type 2 diabetes mellitus Health benefits