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Virologica Sinica 2016年第3期31卷 207-218页

作者： Yanpeng Li ulf Dittmer Yan Wang Jiping Song Binlian Sun Rongge Yang Research Group of HIV Molecular Epidemiology and Virology Center for Emerging Infectious DiseasesState Key Laboratory of VirologyWuhan Institute of VirologyChinese Academy of Sciences Institute for Virology University Hospital EssenUniversity of Duisburg-Essen

A transmission bottleneck occurs during each human immunodeficiency virus(HIV) transmission event, which allows only a few viruses to establish new infection. However, the genetic characteristics of the transmitted viruses that are preferentially selected have not been fully elucidated. Here, we analyzed amino acids changes in the envelope protein during simian immunodeficiency virus(SIV)/HIV deep transmission history and current HIV evolution within the last 15–20 years. Our results confirmed that the V1V2 region of gp120 protein, particularly V1, was preferentially selected. A shorter V1 region was preferred during transmission history, while during epidemic, HIV may evolve to an expanded V1 region gradually and thus escape immune recognition. We then constructed different HIV-1 V1 mutants using different HIV-1 subtypes to elucidate the role of the V1 region in envelope function. We found that the V1 region, although highly variable, was indispensable for virus entry and infection, probably because V1 deletion mutants exhibited impaired processing of gp160 into mature gp120 and gp41. Additionally, the V1 region affected Env incorporation. These results indicated that the V1 region played a critical role in HIV transmission and infection.

关键词： HIV-1 病毒感染传播过程包络函数 SIV 人类免疫缺陷病毒猴免疫缺陷病毒蛋白氨基酸

Triviality of Quantum Electrodynamics Revisited

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Communications in Theoretical Physics 2018年第3期69卷 263-265页

作者： D.Djukanovic J.Gegelia ulf-G.Meiβner Helmholtz Institute Mainz University of MainzD-55099 MainzGermany Institute for Advanced Simulation Institut flit Kernphysik and Julich Center for Hadron PhysicsForschungszentrum JulichD-52425 JfilichGermany Tbilisi State University 0186 TbilisiGeorgia Helmholtz Institut fiir Strahlen-und Kernphysik and Bethe Center for Theoretical Physics Universitat BonnD-53115 BonnGermany

Quantum electrodynamics is often considered to be a trivial *** is based on a number of evidences,both numerical and *** of the strong indications for triviality of QED is the existence of the Landau pole for the running *** show that by treating QED as the leading order approximation of an effective field theory and including the next-to-leading order corrections,the Landau pole is *** also analyze the cutoff dependence of the bare coupling at two-loop order and conclude that the conjecture,that for reasons of self-consistency,QED needs to be trivial is a mere artefact of the leading order approximation to the corresponding effective field theory.

关键词： theory of quantized fields renormalization photons

How the X(5568) Challenges Our Understanding of QCD

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Communications in Theoretical Physics 2016年第5期65卷 593-595页

作者：郭奉困 ulf-G.Mei?ner 邹冰松 Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences Helmholtz-Institut fur Strahlen- und Kernphysik and Bethe Center for Theoretical Physics Universitat Bonn Institute for Advanced Simulation Institut fur Kernphysik and Julich Center for Hadron PhysicsForschungszentrum Julich School of Physical Sciences University of Chinese Academy of Sciences

We discuss the X(5568)particle recently announced by the D0 *** types of models were proposed to explain this structure in the *** pointed out by Burns and Swanson(ar Xiv:1603.04366),none of them provides a satisfactory description of the *** provide additional arguments using general properties of QCD,and conclude that the observation of the X(5568),if confirmed,poses serious challenges to our understanding of nonperturbative QCD.

关键词：非微扰QCD 类模型粒子

The Mesoproterozoic in the Nordic countries

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Episodes 2008年第1期31卷 29-34页

作者： Bernard Bingen Jenny Andersson ulf Soederlund Charlotte Moeller Geological Survey of Norway 7491 Trondheim Norway. Geological Survey of Sweden. Box 670 75128 Uppsala Sweden. Department of Geology GeoBiosphere Science Centre Lund University Soevegatan 12 22362 Lund Sweden. Geological Survey of Sweden Kiliansgatan 10 22350 Lund Sweden.

During the Mesoproterozoic, central Fennoscandia and Laurentia (Greenland) were characterized by a weakly extensional stress regime, as evident from episodic rapakivi granites, dolerite dykes, continental rift intrusives, sandstone basins and continental flood basalts. Along the southwestern active margin of Fennoscandia, the 1.64-1.52 Ga Gothian and 1.52-1.48 Ga Tele-markian accretionary events resulted in oceanwards continental growth. The 1.47-1.42 Ga Hallandian-Danopolonian event included high-grade metamorphism and granite magmatism in southern Fennoscandia. The pre-Sveconorwegian 1.34-1.14 Ga period is characterized by bimodal magmatism associated with sedimentation, possibly reflecting transcurrent tectonics. The Sveconorwegian otogeny involved polyphase imbrication of terranes between 1.14 and 0.97 Ga, as a result of a collision between Baltica and another major plate, followed by relaxation and post-collisional magmatism between 0.96 and 0.90 Ga. Recent geologic data support classical models restoring the Sveconorwegian belt directly to the east of the Grenville belt of Laurentia at 1.0 Ga. Fragments of Paleo- to Mesoproterozoic crust showing late Grenvillian-Sveconorwegian (1.00-0.92 Ga) magmatism and/or metamorphism are exposed in several tectonic levels in the Caledonides of Scandinavia, Svalbard and East Greenland, on both sides of the inferred lapetus suture. Linking these fragments into a coherent late-Grenvillian tectonic model, however, require additional study.

关键词：地球科学中元古代北欧地区格陵兰岛芬诺斯坎底亚

Exploratory study of possible resonances in heavy meson-heavy baryon coupled-channel interactions

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Chinese Physics C 2018年第2期42卷 71-80页

作者：沈超玮 Deborah Rnchen ulf-G.Meiβner 邹冰松 Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences (UCAS) Beijing 100049 China Helmholtz-Institut für Strahlen- und Kernphysik (Theorie) and Bethe Center for Theoretical Physics Universita Bonn D-53115 Bonn Germany

We use a unitary coupled-channel model to study the DAc-D∑c interactions. In our calculation, SU（3）flavor symmetry is applied to determine the coupling constants. Several resonant and bound states with different spin and parity are dynamically generated in the mass range of the recently observed pentaquarks. The approach is also extended to the hidden beauty sector to study the BΛb-B∑b interactions. As the b-quark mass is heavier than the c-quark mass, there are more resonances observed for the BΛb-B∑b interactions and they are more tightly bound.

关键词： coupled-channel interactions heavy meson heavy baryon exotic baryons

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机翼尾迹脱落涡噪声的理论研究(英文)

Chinese Journal of Aeronautics 2001年第2期14卷 65-72页

作者：乔渭阳 ulf Michel Aero-engine Department Northwestern Polytechnical University

The vortex shedding noise has been revealed as an important wing noise source on some modern commercial aircraft based on the fly-over measurements with a planar microphone array by Michel (1998). In this paper, an analytical model is presented for predicting this vortex shedding noise. The downstream wake of a 2-dimensional airfoil is assumed to be dominated by the von Karman vortex street, and the strength and the shedding frequency of the wake vortex are determined from the wake structure model. An aero-acoustic model is developed based on the Howe's unified theory of trailing edge noise and is incorporated with the wake model to predict the sound pressure level and directivity of vortex shedding noise. The predicted vortex shedding frequencies, sound pressure levels and directivities compare favorably with the measured results for 6 modern commercial aircraft.

关键词： Acoustic noise Aircraft models Airfoils Frequencies Microphones Pressure effects Wakes

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第二配位层磺酸根在电催化析氢反应中的作用

Chinese Journal of Catalysis 2023年第2期45卷 88-94页

作者：王妮张学鹏韩金秀雷海涛张清鑫张航张伟 ulf-Peter Apfel 曹睿陕西师范大学化学与化工学院应用表面与胶体化学教育部重点实验室中国陕西西安710119 波鸿鲁尔大学化学与生物化学学院德国弗劳恩霍夫环境、安全与能源技术研究所德国

析氢反应涉及电子和质子转移过程,即PCET过程,需要较大的过电势才可以驱动析氢反应发生.因此,合成过电势低,活性高的催化剂成为研究热点.自然界中,铁铁氢化酶可以将质子高效地还原成氢气.经研究,铁铁氢化酶的结构中有一个氨基基团位于... 详细信息

析氢反应涉及电子和质子转移过程,即PCET过程,需要较大的过电势才可以驱动析氢反应发生.因此,合成过电势低,活性高的催化剂成为研究热点.自然界中,铁铁氢化酶可以将质子高效地还原成氢气.经研究,铁铁氢化酶的结构中有一个氨基基团位于活性金属中心铁的一侧,因此可以精准、有效地将质子传递给金属铁,从而提高催化效率.受自然界启发,很多分子催化剂模拟了自然界中氢化酶的结构,在分子内引入proton-relay基团,促进了析氢过程中PCET的过程.但目前只有关于这类分子催化剂通过促进质子传输进而提高催化效率的文献报道,尚未发现有关其改变氢氢成键方式的研究.前期工作中,本课题组设计合成了卟啉镓并用于电催化质子还原的研究.利用循环伏安法对其析氢活性进行了测试,发现分别以三氟乙酸(TFA)和醋酸(HOAc)作为质子源时,催化析氢的电化学行为不同.在强酸(TFA)体系中,催化剂在经历了两电子还原后,生成的金属氢化物可以直接和质子发生反应,生成氢气.但是在弱酸(HOAc)体系中,生成的金属氢化物需要再经过一电子的还原才可以驱动整个催化反应的进行.在该工作的基础上,通过调研文献得知,在分子内引入酸基团时,可以极大地增加中心金属周围的质子浓度,并且改善质子传输的速率.基于以上想法,在卟啉镓的分子内引入了磺酸基团作为proton-relay的中心,使催化剂能够在弱酸存在的体系中实现强酸的催化析氢路径.本文合成了第二配位层带磺酸基团的卟啉镓化合物(1).在弱酸(HOAc)作为外加质子源时,利用循环伏安法证明了生成的镓氢化合物是真正的活性物种,可以驱动整个催化析氢反应的发生.循环伏安法实验结果表明,化合物1具有很高的催化活性,其TOF值可以达到1.3×10^(5)s^(-1).为了进一步研究催化机理,通过停留光谱实验对该反应进行了原位监测,将化合物1两电子还原后形成的物种(12-)与HOAc的乙腈溶液混合,混合液的紫外光谱可以迅速变回到化合物1原始的光谱,进一步证明了引入磺酸基团可以使生成的镓氢化合物能够直接与弱酸(HOAc)发生反应生成氢气.理论计算结果表明,引入磺酸基团可以显著地降低氢氢成键的能垒.因此,引入磺酸基团,利用限域效应使催化剂周围的质子浓度和强度增强,从而使催化剂能够在弱酸体系中通过强酸的催化路径生成氢气.综上,本文阐明了第二配位层proton-relay基团具有促进质子转移和调控氢氢成键过程的作用,为设计具有优异电催化析氢性能的分子催化剂提供了新的思路.

关键词：分子电催化金属氢化物析氢反应镓氢化合物第二配位层氢氢成键

Isospin-conserving hadronic decay of the D_(s1)(2460) into D_(s)π^(+)π^(-)

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Communications in Theoretical Physics 2023年第5期75卷 119-127页

作者： Meng-Na Tang Yong-Hui Lin Feng-Kun Guo Christoph Hanhart ulf-G.Meißner CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Helmholtz-Institut für Strahlen-und Kernphysik and Bethe Center for Theoretical Physics Universität BonnD-53115 BonnGermany Peng Huanwu Collaborative Center for Research and Education Beihang UniversityBeijing 100191China Institute for Advanced Simulation and Institut für Kernphysik Forschungszentrum JülichD-52425 JülichGermany Tbilisi State University 0186 TbilisiGeorgia

The internal structure of the charm-strange mesons D_(s0)^(*)(2317)and D_(s1)(2460)are the subject of intensive *** widths are small because they decay dominantly through isospinbreaking hadronic channels D_(s0)^(*)(2317)^(+)→D_(s)^(+)π^(0) and D _(s1)(2460)^(+)→D_(s)^(*+)π^(0).The D_(s1)(2460)can also decay into the hadronic final states D_(s)^(+)ππ,conserving *** that case there is,however,a strong suppression from phase *** study the transition D_(s1)(2460)^(+)→D_(s)^(+)π^(+)π^(-)in the scenario that the D_(s1)(2460)is a D^(*)K hadronic *** ππ final state interaction is taken into account through dispersion *** find that the ratio of the partial widths of the Γ(D_(s1)(2460)^(+)→D_(s)^(+)π^(+)π^(-)) / Γ(D_(s1)(2460)^(+)→D_(s)^(*+)π^(0))obtained in the molecular picture is consistent with the existing experimental *** interestingly,we demonstrate that theπ+π−invariant mass distribution shows a double bump structure,which can be used to disentangle the hadronic molecular picture from the compact state picture for the D_(s1)(2460)^(+).Predictions on the B_(s1)^(0)→B_(s)^(0)π^(+)π^(-)are also made.

关键词： hadronic molecule isospin symmetry heavy quark flavor symmetry

The Muruntau gold deposit(Uzbekistan)--A unique ancient hydrothermal system in the southern Tien Shan

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Geoscience Frontiers 2016年第3期7卷 495-528页

作者： ulf Kempe Torsten Graupner Reimar Seltmann Hugo de Boorder Alla Dolgopolova Maarten Zeylmans van Emmichoven Institut fur Mineralogie TU Bergakademie Freiberg Brennhausgasse 14 09596 Freiberg Germany Federal Institute for Geosciences and Natural Resources (BGR) Stilleweg 2 30655 Hannover Germany Centre for Russian and Central EurAsian Mineral Studies (CERCAMS) Department of Earth Sciences Natural History Museum Cromwell Road London SW7 5BD UK Faculty of Geosciences Utrecht University Heidelberglaan 2 3584 CS Utrecht The Netherlands

The Muruntau gold deposit in the Central Kyzylkum,Uzbekistan is one of the largest single gold deposits *** available from the literature are reviewed with the aim to（1） integrate the present knowledge on this unique deposit from Russian and English literature;（2） show the considerable progress made in the understanding of the genesis of the Muruntau deposit during the last decades;and（3） point to problems still open for future *** formation occurred through a multi-stage process involving sedimentation,regional metamorphism including thrusting,magmatism with formation of hornfels aureoles and several stages of hydrothermal *** to recent knowledge,synsedimentary or pure metamorphic formation of gold mineralization seems *** role of granite magmatism occurring roughly within the same time interval as the main hydrothermal gold precipitation remains *** are no signs of interaction of matter between the magma（s） and the hydrothermal system（s）.On the other hand,there was an intense,high-temperature（above 400 ℃）fluid- wall rock interaction resulting in the formation of gold-bearing,cone-like stockworks with veins,veinlets and gold-bearing *** chemical and isotope indicators hint at an involvement of lower-crustal or mantle-related sources as well as of surface waters in ore *** formation through brecciation involving explosion,hydrothermal or tectonic breccias might explain these *** investigations on breccia formation as well as on the exact timing of relevant sedimentary,metamorphic,magmatic and hydrothermal events are recommended.

关键词： Muruntau Gold deposit Fluid inclusions Isotope data Gold composition

A Crowned Killer’s Ré sumeé: Genome, Structure, Receptors, and Origin of SARS-CoV-2

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Virologica Sinica 2020年第6期35卷 673-684页

作者： Shichuan Wang Mirko Trilling Kathrin Sutter ulf Dittmer Mengji Lu Xin Zheng Dongliang Yang Jia Liu Department of Infectious Diseases Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China Institute for Virology University Hospital of EssenUniversity of Duisburg-EssenEssen 45147Germany Joint International Laboratory of Infection and Immunity Huazhong University of Science and TechnologyWuhan 430022China

The recent emergence and rapid global spread of the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2) pose an unprecedented medical and socioeconomic crisis, and the disease caused by it, Coronavirus disease 2019(COVID-19),was declared a pandemic by the World Health Organization(WHO) on March 11, 2020. Chinese scientists and physicians rapidly identified the causative pathogen, which turned out to be a novel betacoronavirus with high sequence similarities to bat and pangolin coronaviruses. The scientific community has ignited tremendous efforts to unravel the biological underpinning of SARS-CoV-2, which constitutes the foundation for therapy and vaccine development strategies. Here, we summarize the current state of knowledge on the genome, structure, receptor, and origin of SARS-CoV-2.

关键词： Coronavirus Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2) Coronavirus disease 2019(COVID-19) Genome Structure Receptor Origin