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Transition States in Protein Folding

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Communications in Computational Physics 2010年第2期7卷 283-300页

作者： Thomas r.Weikl max Planck Institute of Colloids and Interfaces Department of Theory and Bio-Systems14424 PotsdamGermany

The folding dynamics of small single-domain proteins is a current focus ofsimulations and experiments. Many of these proteins are ‘two-state folders’, i.e. pro-teins that fold rather directly from the denatured state to the native state, without pop-ulating metastable intermediate states. A central question is how to characterize theinstable, partially folded conformations of two-state proteins, in particular the rate-limiting transition-state conformations between the denatured and the native *** partially folded conformations are short-lived and cannot be observed directlyin experiments. However, experimental data from detailed mutational analyses of thefolding dynamics provide indirect access to transition states. The interpretation ofthese data, in particular the reconstruction of transition-state conformations, requiressimulation and modeling. The traditional interpretation of the mutational data aimsto reconstruct the degree of structure formation of individual residues in the transitionstate, while a novel interpretation aims at degrees of structure formation of cooperativesubstructures such as α-helices and β-hairpins. By splitting up mutation-induced freeenergies into secondary and tertiary structural components, the novel interpretationresolves some of the inconsistencies of the traditional interpretation.

关键词： Protein folding transition-state theory molecular dynamics mutational analysis

Tango Controls and data pipeline for petawatt laser experiments

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High Power Laser Science and engineering 2023年第4期 6-12页

作者： Nils Wei?e Leonard Doyle Johannes Gebhard Felix Balling Florian Schweiger Florian Haberstroh Laura D.Geulig Jinpu Lin Faran Irshad Jannik esslinger Sonja Gerlach max Gilljohann Vignesh Vaidyanathan Dennis Siebert Andreas Münzer Gregor Schilling J?rg Schreiber Peter G.Thirolf Stefan Karsch Andreas D?pp Ludwig-maximilians-Universit?t München

The Centre for Advanced Laser Applications in Garching, Germany, is home to the ATLAS-3000 multi-petawatt laser,dedicated to research on laser particle acceleration and its applications. A control system based on Tango Controls is implemented for both the laser and four experimental areas. The device server approach features high modularity,which, in addition to the hardware control, enables a quick extension of the system and allows for automated data acquisition of the laser parameters and experimental data for each laser shot. In this paper we present an overview of our implementation of the control system, as well as our advances in terms of experimental operation, online supervision and data processing. We also give an outlook on advanced experimental supervision and online data evaluation ± where the data can be processed in a pipeline ± which is being developed on the basis of this infrastructure.

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The genetic link between the Siberian Continental Flood basalts and alkaline magmatism of Polar Siberia （Maymecha-Kotuy area）

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The genetic link between the Siberian Continental Flood basa...

Polar Coronal Holes During Solar Cycles 22 and 23

International Conference on Continental Volcanism

作者： Kogarko L.N. Zartman r.e. Vernadsky Institute of Geochemistry Moscow max-Planck-Institute for Chemistry Department of CosmochemistryP.O. Box 306055020 MainzGermany

＜正＞Covering a vast area of the northern Siberian platform are the Siberian flood basalts （SFB）, which make up one of the world’s largest magmatic provinces. Along the northeastern margin of the SFB province lie the Maymecha-Kotuy alkaline-ultramafic complex, consisting of a large volume of alkaline lavas, numerous dikes, and the Guli massif together with numerous other, smaller alkaline plutons. The genetic link between the SFB and the Maymecha-Kotuy complex continues to be a subject of active debate. Although the rocks in both units have essentially the same age close to the Permian-Triassic boundary, questions

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Chinese Journal of Astronomy and Astrophysics 2005年第5期5卷 531-538页

作者： Jun Zhang J. Woch S. Solanki National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 max-Planck-Institut fiir Sonnensystemforschung Katlenburg-Lindau D-37191 Germany

Data from the Solar Wind Ion Composition Spectrometer （SWICS） on Ulysses and synoptic maps from Kitt Peak are used to analyze the polar coronal holes of solar activity cycles 22 and 23 （from 1990 to end of 2003）. In the beginning of the declining phase of solar cycles 22 and 23, the north polar coronal holes （PCHs） appear about one year earlier than the ones in the south polar region. The solar wind velocity and the solar wind ionic charge composition exhibit a characteristic dependence on the solar wind source position within a PCH. From the center toward the boundary of a young PCH, the solar wind velocity decreases, coinciding with a shift of the ionic charge composition toward higher charge states. However, for an old PCH, the ionic charge composition does not show any obvious change, although the latitude evolution of the velocity is similar to that of a young PCH.

关键词： Sun: coronal - Sun: particle emission - Sun: solar wind

P450-mediated dehydrotyrosine formation during WS9326 biosynthesis proceeds via dehydrogenation of a specific acylated dipeptide substrate

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Acta Pharmaceutica Sinica B 2023年第8期13卷 3561-3574页

作者： Songya Zhang Lin Zhang Anja Greule Julien Tailhades edward Marschall Panward Prasongpholchai Daniel J.Leng Jingfan Zhang Jing Zhu Joe A.Kaczmarski ralf B.Schittenhelm Oliver einsle Colin J.Jackson Fabrizio Alberti Andreas Bechthold Youming Zhang Manuela Tosin Tong Si max J.Cryle CAS Key Laboratory of Quantitative engineering Biology Shenzhen Institute of Synthetic BiologyShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China Institut für Biochemie Albert-Ludwigs-Universitat FreiburgFreiburg 79104Germany Department of Biochemistry and Molecular Biology the Monash Biomedicine Discovery InstituteMonash UniversityClayton 3800VICAustralia eMBL Australia Monash UniversityClayton 3800VICAustralia ArC Centre of excellence for Innovations in Peptide and Protein Science Clayton 3800VICAustralia Department of Chemistry University of WarwickGibbet Hill RoadCoventry CV47ALUK School of Life Sciences University of WarwickGibbet Hill CampusCoventry CV47ALUK research School of Chemistry the Australian National UniversityActon 2601ACTAustralia Monash Proteomics and Metabolomics Facility Monash UniversityClayton 3800VICAustralia Institute of Pharmaceutical Sciences Albert-Ludwigs-Universitat Freiburg79104Germany

WS9326A is a peptide antibiotic containing a highly unusual N-methyl-e-2-3-dehydrotyrosine(NMet-Dht)residue that is incorporated during peptide assembly on a non-ribosomal peptide synthetase(NrPS).The cytochrome P450 encoded by sas16(P450Sas)has been shown to be essential for the formation of the alkene moiety in NMet-Dht,but the timing and mechanism of the P450Sas-mediatedα,β-dehydrogenation of Dht remained ***,we show that the substrate of P450Sas is the NrPS-associated peptidyl carrier protein(PCP)-bound dipeptide intermediate(Z)-2-pent-1′-*** demonstrate that P450Sas-mediated incorporation of the double bond follows N-methylation of the Tyr by the N-methyl transferase domain found within the NrPS,and further that P450Sas appears to be specific for substrates containing the(Z)-2-pent-1’-enyl-cinnamoyl group.A crystal structure of P450Sas reveals differences between P450Sas and other P450s involved in the modification of NrPS-associated substrates,including the substitution of the canonical active site alcohol residue with a phenylalanine(F250),which in turn is critical to P450Sas activity and WS9326A ***,our results suggest that P450Sas catalyses the direct dehydrogenation of the NrPS-bound dipeptide substrate,thus expanding the repertoire of P450 enzymes that can be used to produce biologically active peptides.

关键词： Cytochrome P450 Non-ribosomal peptide synthetase Protein crystal structure enzyme mechanism Natural products Peptideantibiotic

Self-Optimizing Flexible Assembly Systems

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Computer Technology and Application 2011年第5期2卷 333-343页

作者： robert Schmitt Peter Loosen Christian Brecher Alberto Pavim max Funck Valentin Morasch Alexander Gatej Nicolas Pyschny Sebastian Haag Laboratory for Machine Tools and Production engineering WZL RWTH Aachen University Aachen 52074 Germany Chair for Technology of Optical Systems TOS RWTH Aachen University Aachen 52074 Germany Fraunhofer-Institute for Laser Technology ILT Aachen 52074 Germany Fraunhofer-Institute for Production Technology IPT Aachen 52074 Germany

Today＇s production systems are demanded to exhibit an increased flexibility and mutability in order to deal with dynamically changing conditions, objectives and an increasing number of product variants within industrial turbulent environments. Flexible automated systems are requested in order to improve dynamic production efficiency, e.g. robot-based hardware and PC-based controllers, but these usually induce a significantly higher production complexity, whereby the efforts for planning and programming, but also setups and reconfiguration, expand. In this paper a definition and some concepts of self-optimizing assembly systems are presented to describe possible ways to reduce the planning efforts in complex production systems. The concept of self-optimization in assembly systems will be derived from a theoretical approach and will be transferred to a specific application scenario---the automated assembly of a miniaturized solid state laser--where the challenges of unpredictable influences from e.g. component tolerances can be overcome by the help of self-optimization.

关键词： Flexible assembly systems self-optimization multi agent systems cognition tolerance matching sensor data fusion.

Tango Controls and data pipeline for petawatt laser experiments

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High Power Laser Science and engineering 2023年第4期11卷 2-8页

作者： Nils Weiße Leonard Doyle Johannes Gebhard Felix Balling Florian Schweiger Florian Haberstroh Laura D.Geulig Jinpu Lin Faran Irshad Jannik esslinger Sonja Gerlach max Gilljohann Vignesh Vaidyanathan Dennis Siebert Andreas Münzer Gregor Schilling Jörg Schreiber Peter G.Thirolf Stefan Karsch Andreas Döpp Ludwig-maximilians-Universität München GarchingGermany

The Centre for Advanced Laser Applications in Garching,Germany,is home to the ATLAS-3000 multi-petawatt laser,dedicated to research on laser particle acceleration and its applications.A control system based on Tango Controls is implemented for both the laser and four experimental *** device server approach features high modularity,which,in addition to the hardware control,enables a quick extension of the system and allows for automated data acquisition of the laser parameters and experimental data for each laser *** this paper we present an overview of our implementation of the control system,as well as our advances in terms of experimental operation,online supervision and data *** also give an outlook on advanced experimental supervision and online data evaluation–where the data can be processed in a pipeline–which is being developed on the basis of this infrastructure.

关键词： data processing high-power laser experiments laser-plasma acceleration online diagnostics

Single and joint stress of acetochlor and Pb on three agricultural crops in northeast China

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Journal of environmental Sciences 2007年第6期19卷 719-724页

作者： CHAO Lei ZHOU Qi-xing CHeN SU CUI Shuang WANG Mei-e Key Laboratory of Terrestrial ecological Process Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China The Graduate School of Chinese Academy of Sciences Beijing 100039 China College of environmental Science and engineering Nankai University lianjin 300071 China

In order to evaluate ecological risk of agrochemicals in agricultural environment, single and joint toxic effects of an important herbicide and a typical heavy metal on root elongation of crops were investigated. Seeds of the three crops including wheat （Triticum aestivum）, Chinese cabbage （Brassica pekimensis） and soybean （Glycine max） as the main crops in northeast China were exposed to acetochior as a herbicide and lead （Pb） as a heavy metal using the pot-culture method, and meadow brown soil as one of the main soils distributed in northeast China was applied in the investigation. The results indicated that the interactive effects of the two pollutants on root elongation of the three crops were very complicated although they had markedly significant （P〈0.01） linear interrelationships based on the regression analyses. When the concentration of added Pb^2＋ reached 200 mg/kg, acetochlor and Pb had an antagonistic effect on the inhibition of root elongation of the three crops. However, acetochlor and Pb had significantly （P〈0.05） synergic effects on the inhibition of root elongation when concentration of added Pb^2＋ was up to 1000 mg/kg. At the low concentration of added Pb, joint toxicity of acetochlor and Pb was more dependent on the concentration of Pb. Among the three crops, wheat was the most sensitive to the toxicity of Pb and Chinese cabbage was the most sensitive to the toxicity of acetochlor.

关键词： acetochlor Pb ecotoxicology joint effect Chinese cabbage (Brassica pekimensis) soybean (Glycine max) wheat (Triticum aestivum)

recent advances in energy efficient PeO processing of aluminium alloys

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Transactions of Nonferrous Metals Society of China 2017年第7期27卷 1439-1454页

作者： e.MATYKINA r.ArrABAL M.MOHeDANO B.MINGO J.GONZALeZ A.PArDO M.C.MerINO Departamento de Ciencia de Materiales Facultad de Ciencias QuímicasUniversidad Complutense28040 MadridSpain Helmholtz.Zentrum Geesthacht Magnesium Innovation CentreInstitute of Materials ResearchMax-Planck-Str.1D-21502 GeesthachtGermany

Plasma electrolytic oxidation(PeO)coatings developed under voltage-controlled mode on various commercial wrought,gravity cast and rheocast aluminium alloys were discussed with respect to enhancement of their tribological and corrosionperformance and minimization of the PeO energy *** is demonstrated that use of conventional porous anodic filmprecursors reduces the PeO energy consumption by up to50%.The wear of6082alloy with PeO coatings with addedα-Al2O3particles is two times lower compared with electrolytic hard *** long-term corrosion resistance of the PeO-coatedA356rheocast alloy is enhanced via use of a precursor and hydrophobic post-treatment.

关键词： aluminium anodizing plasma electrolytic oxidation wear corrosion