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Frontiers of Environmental Science & Engineering 2009年第2期3卷 152-170页

作者： lutz AHRENS Merle PLASSMANN Zhiyong XIE Ralf EBINGHAUS Institute for Coastal Research GKSS Research Centre Geesthacht GmbHD-21502 GeesthachtGermany Institute for Ecology and Environmental Chemistry Leuphana University of LüneburgD-21335 LüneburgGermany Department of Applied Environmental Science(ITM) Stockholm UniversitySE-10691 StockholmSweden

The distribution of polyfluoroalkyl compounds(PFCs)in the dissolved and particulate phase and their discharge from the river Elbe into the North Sea were *** PFCs quantified included C_(4)-C_(8) perfluorinated sulfonates(PFSAs),6∶2 fluorotelomer sulfonate(6∶2 FTS),C_(6) and C_(8) perfluorinated sulfinates(PFSiAs),C_(4)-C_(12) perfluorinated carboxylic acids(PFCAs),perfluoro-3,7-dimethyl-octanoic acid(3,7m_(2)-PFOA),perfluorooctane sulfonamide(FOSA),and n-ethyl perfluroctane sulfonamidoethanol(EtFOSE).PFCs were mostly distributed in the dissolved phase,where perfluorooctanoic acid(PFOA)dominated with 2.9–12.5 ng/*** the suspended particulate matter FOSA and perfluorooctane sulfonate(PFOS)showed the highest concentrations(4.0 ng/L and 2.3 ng/L,respectively).The total flux ofΣPFCs from the river Elbe was estimated to be 802 kg/year for the dissolved phase and 152 kg/year for the particulate *** indicates that the river Elbe acts as a source of PFCs into the North ***,the concentrations of perfluorobutane sulfonate(PFBS)and perfluorobutanoic acid(PFBA)in the North Sea were higher than that in the river Elbe,thus an alternative source must exist for these compounds.

关键词： polyfluoroalkyl compounds(PFCs) perfluorooctane sulfonate(PFOS) perfluorooctanoic acid(PFOA) surface water water-particulate partitioning

Cobaltaelectro-Catalyzed C—H Acyloxylation

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Chinese Journal of Chemistry 2019年第6期37卷 552-556页

作者： Cong Tian Uttam Dhawa Julia Struwe lutz Ackermann Institut fur Organische und Biomolekulare Chemie Georg-August-Universitat GottingenTammannstraβe 237077 GottingenGermany

Cobaltaelectrocatalysis set the stage for sustainable C—H acyloxylations in biomass-derived γ-valerolactone as a renewable solvent. The sustainable electrocatalysis regime featured ample scope, along with high level... 详细信息

关键词： C-H activation cobalt electrosynthesis biomass solvent

Dynamics of strong and radiative decays of D_s-mesons in the hadrogenesis conjecture

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Chinese Physics C 2010年第9期34卷 1320-1323页

作者： M.Soyeur M.F.M.lutz Irfu/SPhN CEA/Saclay GSI Planckstrasse 1

The positive parity scalar D ＊ s0 （2317） and axial-vector D ＊ s1 （2460） charmed strange mesons are generated by coupled-channel dynamics through the s-wave scattering of Goldstone bosons off the pseudoscalar and vector D（D s ）-meson ground *** specific masses of these states are obtained as a consequence of the attraction arising from the Weinberg-Tomozawa interaction in the chiral *** corrections to order Q 2 χ are calculated and found to be *** D ＊ s0 （2317） and D ＊ s1 （2460） mesons decay either strongly into the isospin-violating π 0 D s and π 0 D ？ s channels or *** show that the π 0-η and （K^ 0 D ^＋-K^ ＋ D^ 0 ） mixings act constructively to generate strong widths of the order of 140 keV and emphasize the sensitivity of this value to the KD component of the *** one-loop contribution to the radiative decay amplitudes of scalar and axial-vector states is calculated using the electromagnetic Lagrangian to chiral order Q 2 χ .We show the importance of taking into account processes involving light vector mesons explicitly in the dynamics of electromagnetic *** radiative width are sensitive to both η D s and KD components,hence providing information complementary to the strong widths on the positive parity D s-meson structure.

关键词： charmed mesons D*s0 (2317) D*s1 (2460)

Total Restrained Bondage in Graphs

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Acta Mathematica Sinica,English Series 2013年第6期29卷 1033-1042页

作者： Nader JAFARI RAD Roslan HASNI Joanna RACZEK lutz VOLKMANN Department of Mathematics Shahrood University of Technology Department of Mathematics Faculty of Science and Technology University Malaysia Terengganu Department of Mathematics Gdansk University of Technology Lehrstuhl II fr Mathematik RWTH Aachen University

A subset S of vertices of a graph G with no isolated vertex is a total restrained dominating set if every vertex is adjacent to a vertex in S and every vertex in V （G） S is also adjacent to a vertex in V （G） S. The total restrained domination number of G is the minimum cardinality of a total restrained dominating set of G. In this paper we initiate the study of total restrained bondage in graphs. The total restrained bondage number in a graph G with no isolated vertex, is the minimum cardinality of a subset of edges E such that G E has no isolated vertex and the total restrained domination number of G E is greater than the total restrained domination number of G. We obtain several properties, exact values and bounds for the total restrained bondage number of a graph.

关键词： Domination total restrained domination bondage

Library and Information Science Papers Discussed on Twitter: A new Network-based Approach for Measuring Public Attention

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Journal of Data and Information Science 2020年第3期5卷 5-17页

作者： Robin Haunschild Loet Leydesdorff lutz Bommann Max Planck Institute for Solid State Research Heisenbergstr.170569 StuttgartGermany Amsterdam School of Communication Research(ASCoR) University of AmsterdamPB 157931001 NG AmsterdamThe Netherlands Administrative Headquarters of the Max Planck Society Division for Science and Innovation StudiesHofgartenstr.880539 MunichGermany

Purpose: In recent years, one can witness a trend in research evaluation to measure the impact on society or attention to research by society(beyond science). We address the following question: can Twitter be meaningfully used for the mapping of public and scientific discourses?Design/methodology/approach: Recently, Haunschild et al.(2019) introduced a new network-oriented approach for using Twitter data in research evaluation. Such a procedure can be used to measure the public discussion around a specific field or topic. In this study, we used all papers published in the Web of Science(WoS, Clarivate Analytics) subject category Information Science & Library Science to explore the publicly discussed topics from the area of library and information science(LIS) in comparison to the topics used by scholars in their publications in this ***: The results show that LIS papers are represented rather well on Twitter. Similar topics appear in the networks of author keywords of all LIS papers, not tweeted LIS papers, and tweeted LIS papers. The networks of the author keywords of all LIS papers and not tweeted LIS papers are most similar to each *** limitations: Only papers published since 2011 with DOI were *** implications: Although Twitter data do not seem to be useful for quantitative research evaluation, it seems that Twitter data can be used in a more qualitative way for mapping of public and scientific ***/value: This study explores a rather new methodology for comparing public and scientific discourses.

关键词： Altmetrics Twitter News Hashtags Author keywords

Linear global stability of a confined plume

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Theoretical & Applied Mechanics Letters 2015年第3期5卷 126-128页

作者： lutz Lesshafft Laboratoire d'Hydrodynamique CNRS-Ecole polytechnique

A linear stability analysis is performed for a plume flow inside a cylinder of aspect ratio 1. The configu- ration is identical to that used by Lopez and Marques （2013） for their direct numerical simulation study, It is found that the first bifurcation, which leads to a periodic axisymmetric flow state, is accurately pre- dicted by linear analysis： both the critical Rayleigh number and the global frequency are consistent with the reported DNS results. It is further shown that pressure feedback drives the global mode, rather than absolute instability.

关键词： Plume Linear instability Laminar flow stability Buoyancy-driven instability Bifurcation and symmetry breaking

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

Biomechanische Untersuchungsergebnisse ber die verbesserte Verankerung von Pedikelschraubenmit resorbierbarem Zement in menschenlichen Wirbelk rpern

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Journal of Huazhong University of Science and Technology(Medical Sciences) 2001年第1期21卷 48-51页

作者：邵景范罗永湘 Luo Yongxiang lutz Claes Lothar Kinzl Abteilung für Chirurgie Tongji KlinikTongji medizinisches institutHuazhong Universitat für Wissenschaft und Technik Abteilung für Unfallchirurgie Hand-und Wiederherstellungschirurgie der Universitat UlmDeutschland Abteilung für Unfallchirurgische Forschung und Biomechanik der Universitat Ulm Deutschland

Die Prim rstabilit t von Pedikelschrauben im Knochen h ngt in hohem Masse von der Knochendichte ab. Die Augmentation mit Zement ist ein klinisch einsetzbares Verfahren, um die Schrauben Verankerung im osteoporotischen Knochen zu *** dieser Studie wurde eine neuartiges resorbierbares Knochenersatzmaterial (α BSM TM ) für diese Augmentation benutzt. Biomechanische Testungen wurden in vitro bei 16 Lendwirbelk rpern (L3-L5) aus 6 Individuen(75,2±13,7 Jahre) durchgeführt. Vor der biomechanischen Testung wurde bei allen Pr paraten die trabekul re Knochendichte mittels pQCT gemessen und beide Pedikel mit USS Pedikelschrauben (5,0 mm × 45 mm) besetzt, von welchen eine mit α BSM TM augmentiert war. Beim axialen Auszugstest wurden die maximale axiale Auszugskraft (F max) sowie die Energieaufnahme bestimmt. Der Medianwert der F max stieg beim Auszugstest durch die Zementierung mit α BSM TM um 80 % von 370 N (ohne Zement) auf 665 N (mit Zement). Die Energieaufnahme bis zum Erreichen der F max (E F max) und bei Dislokation bis 2,0 mm (E 2 mm) steigerte sich ebenfalls um 83 % und 68 %. Die Unterschiede waren signifikant. (Wilcoxon′s Test, P <0,01) Die Ausreisskrafte F max (ohne oder mit Zement) korrelierten eng mit der Knochendichte ( r =0,9056 und r =0,9585). Unsere Resultate zeigen, da eine Augmentation mit dem α BSM TM die primare Stabilitat von Pedikelschrauben verbessern kann. Der Effekt scheint auf einer Optimierung der Kontaktfl che und einer Aussteifung der schraubennahen Spongiosa zu beruhen. Das Material k nnte geeignet sein, die Verankerung von Pedikelschrauben bei osteoporotischen Patieten zu verbessern.

关键词： Biomechanik Zement Pedikelschraube Stabilit t Wirbelk rper

Versatile multiplexed super-resolution imaging of nanostructures by Quencher-Exchange-PAINT

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Nano Research 2018年第12期11卷 6141-6154页

作者： Tobias lutz Alexander H.Clowsley Ruisheng Lin Stefano Pagliara Lorenzo Di Michele Christian Soeller Living Systems Institute & Biomedical Physics University of ExeterExeter EX44QDUK Cavendish Laboratory University of CambridgeCambridge CB30HEUK

The optical super-resolution technique DNA-PAINT (Point Accumulation Imaging in Nanoscale Topography) provides a flexible way to achieve imaging of nanoscale structures at ∼10-nanometer resolution. In DNA-PAINT, fluorescently labeled DNA “imager” strands bind transiently and with high specificity to complementary target “docking” strands anchored to the structure of interest. The localization of single binding events enables the assembly of a super-resolution image, and this approach effectively circumvents photobleaching. The solution exchange of imager strands is the basis of Exchange-PAINT, which enables multiplexed imaging that avoids chromatic aberrations. Fluid exchange during imaging typically requires specialized chambers or washes, which can disturb the sample. Additionally, diffusional washout of imager strands is slow in thick samples such as biological tissue slices. Here, we introduce Quencher-Exchange-PAINT—a new approach to Exchange-PAINT in regular open-top imaging chambers—which overcomes the comparatively slow imager strand switching via diffusional imager washout. Quencher-Exchange-PAINT uses “quencher” strands, i.e., oligonucleotides that prevent the imager from binding to the targets, to rapidly reduce unwanted single-stranded imager concentrations to negligible levels, decoupled from the absolute imager concentration. The quencher strands contain an effective dye quencher that reduces the fluorescence of quenched imager strands to negligible levels. We characterized Quencher-Exchange-PAINT when applied to synthetic, cellular, and thick tissue samples. Quencher-Exchange-PAINT opens the way for efficient multiplexed imaging of complex nanostructures, e.g., in thick tissues, without the need for washing steps.

关键词： super-resolution microscopy fluorescence imaging DNA nanotechnology DNA-PAINT fluorescence quencher

Integration of Carbon Assimilation Modes with Photosynthetic Light Capture in the Green Alga Chlamydomonas reinhardtii

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Molecular Plant 2014年第10期7卷 1545-1559页

作者： Hanna Bergera Olga Blifernez-Klassen Matteo Ballottari Roberto Bassi lutz Wobbe Olaf Kruse Bielefeld University Faculty of Biology Center for Biotechnology (CeBiTec) Universitatsstrasse 27 33615 Bielefeld Germany Universita degli Studi di Verona Department of Biotechnology strada Le Grazie 15 37134 Verona Italy

The unicellular green alga Chlamydomonas reinhardtii is capable of using organic and inorganic carbon sources simultaneously, which requires the adjustment of photosynthetic activity to the prevailing mode of carbon assimilation. We obtained novel insights into the regulation of light-harvesting at photosystem II （PSII） following altered carbon source avail- ability. In C. reinhardtii, synthesis of PSll-associated light-harvesting proteins （LHCBMs） is controlled by the cytosolic RNA- binding protein NAB1, which represses translation of particular LHCBM isoform transcripts. This mechanism is fine-tuned via regulation of the nuclear NAB1 promoter, which is activated when linear photosynthetic electron flow is restricted by CO2- limitation in a photoheterotrophic context. In the wild-type, accumulation of NAB1 reduces the functional PSII antenna size, thus preventing a harmful overexcited state of PSII, as observed in a NABl-less mutant. We further demonstrate that trans- lation control as a newly identified long-term response to prolonged CO2-1imitation replaces LHCII state transitions as a fast response to PSII over-excitation. Intriguingly, activation of the long-term response is perturbed in state transition mutant stt7, suggesting a regulatory link between the long- and short-term response. We depict a regulatory circuit operating on distinct timescales and in different cellular compartments to fine-tune light-harvesting in photoheterotrophic eukaryotes.

关键词： light-harvesting antenna translation control state transitions NAB1 carbon metabolism Chlamydomonasreinhardtii.