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Observation of a single protein by ultrafast X-ray diffraction

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Light(Science & Applications) 2024年第1期13卷 80-90页

作者： Tomas Ekeberg Dameli Assalauova Johan Bielecki Rebecca Boll Benedikt J.Daurer Lutz A.Eichacker Linda E.Franken Davide E.Galli Luca Gelisio Lars Gumprecht Laura H.Gunn Janos Hajdu Robert Hartmann Dirk Hasse Alexandr Ignatenko Jayanath Koliyadu Olena Kulyk Ruslan Kurta Markus Kuster Wolfgang Lugmayr Jannik Lübke Adrian P.Mancuso Tommaso Mazza Carl Nettelblad Yevheniy Ovcharenko Daniel E.Rivas Max Rose Amit K.Samanta Philipp Schmidt Egor Sobolev Nicusor Timneanu Sergey Usenko Daniel Westphal Tamme Wollweber Lena Worbs Paul Lourdu Xavier Hazem Yousef Kartik Ayyer Henry N.Chapman Jonas A.Sellberg Carolin Seuring Ivan A.Vartanyants Jochen Küpper Michael Meyer Filipe R.N.C.Maia Laboratory of Molecular Biophysics Department of Cell and Molecular BiologyUppsala UniversityHusargatan 3(Box 596)SE-75124 UppsalaSweden Deutsches Electronen-Synchrotron DESY Notkestrasse 8522607 HamburgGermany European XFEL Holzkoppel 422869 SchenefeldGermany Diamond Light Source Harwell Science&Innovation CampusDidcot OX110DEUK University of Stavanger Centre Organelle ResearchRichard-Johnsensgate 44021 StavangerNorway Leibniz Institute for Experimental Virology(HPI) Centre for Structural Systems BiologyNotkestraße 8522607 HamburgGermany Dipartimento di Fisica“Aldo Pontremoli” Universitàdegli Studi di Milanovia Celoria 1620133 MilanoItaly Center for Free-Electron Laser Science DESY22607 HamburgGermany Plant Biology Section School of Integrative Plant ScienceCornell UniversityIthacaNY 14853USA PNSensor GmbH Otto-Hahn-Ring 6D-81739 MünchenGermany Biomedical and X-Ray Physics Department of Applied PhysicsAlbaNova University CenterKTH Royal Institute of TechnologySE-10691 StockholmSweden ELI Beamlines/IoP Institute of Physics AS CR v.v.i.Na Slovance 218221 Prague 8Czech Republic Multi-User CryoEM Facility Centre for Structural Systems BiologyNotkestr.8522607 HamburgGermany University Medical Center Hamburg-Eppendorf(UKE) Martinistrasse 5220246 HamburgGermany The Hamburg Center for Ultrafast Imaging Universität HamburgLuruper Chaussee 14922761 HamburgGermany Department of Physics Universität HamburgLuruper Chaussee 14922761 HamburgGermany Department of Chemistry and Physics La Trobe Institute for Molecular ScienceLa Trobe UniversityMelbourneVIC 3086Australia Division of Scientific Computing Science for Life LaboratoryDepartment of Information TechnologyUppsala UniversityBox 337SE-75105 UppsalaSweden European Molecular Biology Laboratory c/o DESYNotkestrasse 8522607 HamburgGermany Department of Physics and Astronomy Uppsala UniversityBox 516SE-75120 UppsalaSweden Max Planck Institute for the Structure and Dynamics of Matter Luruper Chaussee 14922761 HamburgGe

The idea of using ultrashort X-ray pulses to obtain images of single proteins frozen in time has fascinated and inspired *** was one of the arguments for building X-ray free-electron *** to theory,the extremely intense pulses provide sufficient signal to dispense with using crystals as an amplifier,and the ultrashort pulse duration permits capturing the diffraction data before the sample inevitably *** was first demonstrated on biological samples a decade ago on the giant *** then,a large collaboration has been pushing the limit of the smallest sample that can be *** ability to capture snapshots on the timescale of atomic vibrations,while keeping the sample at room temperature,may allow probing the entire conformational phase space of *** we show the first observation of an X-ray diffraction pattern from a single protein,that of Escherichia coli GroEL which at 14 nm in diameter is the smallest biological sample ever imaged by X-rays,and demonstrate that the concept of diffraction before destruction extends to single *** the pattern,it is possible to determine the approximate orientation of the *** experiment demonstrates the feasibility of ultrafast imaging of single proteins,opening the way to single-molecule time-resolved studies on the femtosecond timescale.

关键词： smallest intense ultrafast

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具有半子模式欧拉拓扑绝缘体的声学观测

Science Bulletin 2024年第11期69卷 1653-1659页

作者：姜斌 Adrien Bouhon 吴世巧孔泽霖林志康 Robert-Jan Slager 蒋建华 Suzhou Institute for Advanced research University of Science and Technology of ChinaSuzhou 215123China School of Physical Science and Technology&Collaborative Innovation Center of Suzhou Nano Science and Technology Soochow UniversitySuzhou 215006China TCM Group Cavendish LaboratoryUniversity of CambridgeCambridge CB30HEUK NORDITA Stockholm University and KTH Royal Institute of TechnologyStockholm SE-10691Sweden

Topological band theory has conventionally been concerned with the topology of bands around a single gap. Only recently non-Abelian topologies that thrive on involving multiple gaps were studied, unveiling a new horizon in topological physics beyond the conventional paradigm. Here, we report on the first experimental realization of a topological Euler insulator phase with unique meronic characterization in an acoustic metamaterial. We demonstrate that this topological phase has several nontrivial features:First, the system cannot be described by conventional topological band theory, but has a nontrivial Euler class that captures the unconventional geometry of the Bloch bands in the Brillouin ***, we uncover in theory and probe in experiments a meronic configuration of the bulk Bloch states for the first time. Third, using a detailed symmetry analysis, we show that the topological Euler insulator evolves from a non-Abelian topological semimetal phase via. the annihilation of Dirac points in pairs in one of the band gaps. With these nontrivial properties, we establish concretely an unconventional bulk-edge correspondence which is confirmed by directly measuring the edge states via. pump-probe techniques. Our work thus unveils a nontrivial topological Euler insulator phase with a unique meronic pattern and paves the way as a platform for non-Abelian topological phenomena.

关键词： Euler insulators Meronic waves Acoustic metamaterials Topological phases of matter

Characterization of force networks in a dense high-shear system

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Particuology 2018年第3期16卷 215-221页

作者： Mohammad Khalilitehrani Srdjan Sasic Anders Rasmuson Department of Chemistry and Chemical Engineering Chalmers University of Technology SE-412 96 Goteborg Sweden Department of Applied Mechanics Chalmers University of Technology SE-412 96 Gteborg Sweden

We detect strong force networks in a dense high-shear system and study their structure and stability in response to variations in the shearing rate. The presence of strong force networks, which usually have a heterogeneous structure, restricts particle movements and can impose non-local mechanisms of momentum transfer. We identify such networks in a dense high-shear system using a community detec- tion algorithm. Moreover, we explain the association between the mechanisms of momentum transfer and the structure, population, strength, and stability of the force networks by tracking the spatial and temporal evolution of the detected networks. In addition, we show that the assumption of a monodis- perse assembly of particles leads to an unrealistic enlargement of the force networks, underestimating both the rate of energy dissipation and the rate of mixing.

关键词： Force networks Community detection Polydispersity

采用中间态设计控制准二维钙钛矿薄膜晶粒尺寸实现高效束缚激子的产生（英文）

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Science China Materials 2024年

作者：李国辉赵文慧林凯赵柯帆王育景牛澳华温荣郑凯波崔艳霞 College of Electronic Information and Optical Engineering Key Laboratory of Interface Science and Engineering in Advanced Materials Key Lab of Advanced Transducers and Intelligent Control System of Ministry of Education Taiyuan University of Technology Chemical Physics Division and NanoLund Lund University

准二维钙钛矿因其高激子结合能而具有优异的光致发光效率,已成为一种极具前景的新型材料.将激子束缚在更小尺寸的晶粒中可以促进双激子的形成,并提高辐射复合效率.然而,合成具有可控晶粒尺寸的高品质准二维钙钛矿薄膜仍然面临挑战.本研...

准二维钙钛矿因其高激子结合能而具有优异的光致发光效率,已成为一种极具前景的新型材料.将激子束缚在更小尺寸的晶粒中可以促进双激子的形成,并提高辐射复合效率.然而,合成具有可控晶粒尺寸的高品质准二维钙钛矿薄膜仍然面临挑战.本研究通过在薄膜制备过程中进行中间相设计来实现晶粒尺寸从500至900 nm可控的准二维钙钛矿薄膜的制备.结果表明,具有更小晶粒的准二维钙钛矿能更高效地产生束缚激子,并具有低至15.89μJ cm-2的受激辐射阈值.此外,飞秒瞬态吸收光谱显示在相同的泵浦能量密度下,束缚激子的衰减时间在具有更小晶粒的二维钙钛矿中更短,约为230.5 ps.证实了更小的晶粒使二维钙钛矿具有更高效的激子复合过程.本研究结果有望用于开发高效束缚激子激光.

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Taxonomic status of grey-headed Yellow Wagtails breeding in western China

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Avian research 2021年第4期12卷 534-543页

作者： Alexander Hellquist Fredrik Friberg Petter Haldén Peter Schmidt Ming Ma Gou Jun Urban Olsson Per Alström Fatburs kvarngata 17 11864 StockholmSweden Xinjiang Institute of Ecology and Geography Chinese Academy of SciencesNo.818 Beijing RoadUrumqi 830011XinjiangChina Xinjiang Birdwatching Society 311 Nongda East RoadUrumqi 830091XinjiangChina Systematics and Bio-diversity Department of Biology and Environmental SciencesUniversity of GothenburgGöteborgSweden Gothenburg Global Biodiversity Centre GothenburgSweden Animal Ecology Department of Ecology and GeneticsEvolutionary Biology CentreUppsala UniversityNorbyvägen 18D75236 UppsalaSweden Key Laboratory of Zoological Systematics and Evolution Institute of ZoologyChinese Academy of SciencesBeijing 100101China Edeby 9 74191 KnivstaSweden Lenabergsvägen 33 74392 VattholmaSweden Tallmovägen 9 75645 UppsalaSweden

Background:Field studies from 2011 onwards have demonstrated the presence of a breeding population of Yellow Wagtails(Motacilla flava)in the Xinjiang Uygur Autonomous Region,China that is phenotypically distinct from known subspecies occurring in *** we describe the plumages and vocalisations of this population and discuss its taxonomic ***:The analysis of plumage is based on field studies and photos available *** of vocalisations are compared with recordings from other Yellow Wagtail populations,and differences are analysed based on *** DNA from one individual is compared to other Yellow Wagtail ***:Unlike *** subspecies breeding in or near Xinjiang,males in the studied population show a blue-grey head without prominent white supercilium,being most similar to the widely disjunct *** differ from the similarly widely allopatric ***,which might occur as a migrant or vagrant in Xinjiang,by on average cleaner yellow breast and more extensive white on the throat,and from the widely disjunct *** and ***,which might also occur on migration in that area,by softer contact calls and slower pace of *** are similar to female *** in *** mitochondrial ND2 tree shows the single sample from Xinjiang to be nested in the clade of western Yellow Wagtail ***:We discuss whether the Xinjiang breeding population could represent an intergrade between subspecies breeding nearby,or whether it is better regarded as a separate as yet unrecognized *** argue that the localization of its apparent range in relation to other subspecies along with fairly consistent male and female plumages suggest that it is more likely to represent an undescribed taxon,but conclude that more research is needed to firmly establish its status.

关键词： Bioacoustics Mitochondrial DNA Morphology Motacilla flava Systematics Undescribed populations

Efficient Sampling in Event-Driven Algorithms for Reaction-Diffusion Processes

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Communications in Computational Physics 2013年第4期13卷 958-984页

作者： Mohammad Hossein Bani-Hashemian Stefan Hellander Per Lotstedt Division of Scientific Computing Department of Information TechnologyUppsala UniversityP.O.Box 337SE-75105 UppsalaSweden

In event-driven algorithms for simulation of diffusing,colliding,and reacting particles,new positions and events are sampled from the cumulative distribution function(CDF)of a probability *** distribution is sampled frequently and it is important for the efficiency of the algorithm that the sampling is *** CDF is known analytically or computed *** formulas are sometimes rather complicated making them difficult to *** CDF may be stored in a table for interpolation or computed directly when it is *** alternatives are compared for chemically reacting molecules moving by Brownian diffusion in two and three *** best strategy depends on the dimension of the problem,the length of the time interval,the density of the particles,and the number of different reactions.

关键词： Event-driven algorithm chemical reactions diffusion efficient sampling

Effect of structural variation in biomass-derived nonfluorinated ionic liquids electrolytes on the performance of supercapacitors

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Journal of Energy Chemistry 2022年第6期31卷 174-184,I0005页

作者： Inayat Ali Khan Yong-Lei Wang Faiz Ullah Shah Chemistry of Interfaces.Lulea University of Technology.SE-97187 Luled Sweden Department of Materials and Environmental Chemistry.Arrhenius Laboratory.Stockholm University.SE-10691Stockholm.Sweden

There is a growing interest in sustainable and high performance supercapacitors(SCs) operating at elevated temperatures as they are highly demanded in heat-durable electronics. Here, we present a biomass-derived nonfluorinated ionic liquid(IL) [P_(4444)][HFuA] and its structural analogue [P_(4444)][TpA]as electrolytes for supercapacitors comprising multiwall carbon nanotubes and activated charcoal(MWCNTs/AC) mixed carbon composite electrodes. A detailed investigation of the effect of scan rate, temperature, potential window and orientation of ions on the electrodes surfaces is performed. The supercapacitors exhibited relatively lower specific capacitance for both [P_(4444)][HFuA] and [P_(4444)][TpA] ILs at room temperature. However, the specific capacitance has significantly increased with an increase in temperature and potential window. The equivalent serie resistances of the SCs is deceased with increasing temperatures, which is a result of improved ionic conductivities of the IL electrolytes. In CV cycling at60 °C, the capacitor with [P_(4444)][HFuA] IL-based electrolyte retained about 90% of its initial capacitance,while the capacitor with [P_(4444)][TpA] IL-based electrolyte retained about 83% of its initial *** computations revealed that the aromatic [FuA]^(-) and [TpA]^(-) anions displayed perpendicular distribution that can effectively neutralize charges on the carbon surfaces. However, the [HFuA]-anion exhibited somewhat tilted configurations on the carbon electrode surfaces, contributing to their outstanding capacitive performance in electrochemical devices.

关键词： Biomass Ionic liquids Carbon electrodes Supercapacitors Molecular dynamic simulations

Host plant choice in the comma butterfly-larval choosiness may ameliorate effects of indiscriminate oviposition

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Insect Science 2014年第4期21卷 499-506页

作者： Gabriella Gamberale-Stille Lina Soderlind Niklas Janz Soren Nylin Department of Zoology Stockholm University 106 92 Stockholm Sweden

In most phytophagous insects, the larval diet strongly affects future fitness and in species that do not feed on plant parts as adults, larval diet is the main source of nitrogen. In many of these insect-host plant systems, the immature larvae are considered to be fully dependent on the choice of the mothers, who, in turn, possess a highly developed host recognition system. This circumstance allows for a potential mother-offspring conflict, resulting in the female maximizing her fecundity at the expense of larval performance on suboptimal hosts. In two experiments, we aimed to investigate this relationship in the polyphagous comma butterfly, Polygonia c-album, by comparing the relative acceptance of low- and medium-ranked hosts between females and neonate larvae both within individuals between life stages, and between mothers and their offspring. The study shows a variation between females in oviposition acceptance of low-ranked hosts, and that the degree of acceptance in the mothers correlates with the probability of acceptance of the same host in the larvae. We also found a negative relationship between stages within individuals as there was a higher acceptance of lower ranked hosts in females who had abandoned said host as a larva. Notably, however, neonate larvae of the comma butterfly did not unconditionally accept to feed from the least favorable host species even when it was the only food source. Our results suggest the possibility that the disadvantages associated with a generalist oviposition strategy can be decreased by larval participation in host plant choice.

关键词： host plant choice insect-host plant interaction mobility oviposition behav-ior parent-offspring conflict specialization

Inverse single-site Fe_(1)(OH)_(x)/Pt(111)model catalyst for preferential oxidation of CO in H_(2)

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Nano research 2022年第1期15卷 709-715页

作者： Chunlei Wang Heloise Tissot Markus Soldemo Junling Lu Jonas Weissenrieder Materials and Nano Physics School of Engineering SciencesKTH Royal Institute of TechnologyStockholm SE-10044Sweden Department of Engineering and Physics Karlstad UniversityKarlstad SE-65188Sweden Department of Chemical Physics Hefei National Laboratory for Physical Sciences at the MicroscaleKey Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education InstitutesUniversity of Science and Technology of ChinaHefei 230026China

Inverse oxide/metal model systems are frequently used to investigate catalytic structure-function relationships at an atomic *** means of a novel atomic layer deposition process,growth of single-site Fe_(1)O_(x) on a Pt(111)single crystal surface was achieved,as confirmed by scanning tunneling microscopy(STM).The redox properties of the catalyst were characterized by synchrotron radiation based ambient pressure X-ray photoelectron spectroscopy(AP-XPS).After calcination treatment at 373 K in 1 mbar O_(2).the chemical state of the catalyst was determined as Fe^(3+).Reduction in 1 mbar H_(2) at 373 K demonstrates a facile reduction to Fe2+and complete hydroxylation at significantly lower temperatures than what has been reported for iron oxide *** reaction conditions relevant for preferential oxidation of CO in H_(2)(PROX),the catalyst exhibits a Fe3+state(ferric hydroxide)at 298 K while re-oxidation of iron oxide clusters does not occur under the same *** oxidation proceeds on the single-site Fei(OH)3 through a mechanism including the loss of hydroxyl groups in the temperature range of 373 to 473 K,but no reaction is observed on iron oxide *** results highlight the high flexibility of the single iron atom catalyst in switching oxidation states,not observed for iron oxide nanoparticles under similar reaction conditions,which may indicate a higher intrinsic activity of such single interfacial sites than the conventional metal-oxide *** summary,our findings of the redox properties on inverse single-site iron oxide model catalyst may provide new insights into applied Fe-Pt catalysis.

关键词： inverse single-site model catalyst Fe_(1)O_(x)/PPt(111) PROX atomic layer deposition synchrotron radiation AP-XPS STM