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Solid-State NMR Spectroscopic Study of Chromophore-Protein Interactions in the Pr Ground State of Plant Phytochrome A

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Molecular Plant 2012年第3期5卷 698-715页

作者： Chen Song Lars-Oliver Essen Wolfgang Ga＇rtner Jon Hughes J6rg Matysik Leids Instituut voor Chemisch Onderzoek Universiteit Leiden PO Box 9502 2300 RA Leiden The Netherlands Fachbereich Chemie Philipps-Universita＇t Marburg Hans-Meerwein-Stral3e D-35032 Marburg Germany Max-Planck-lnstitut for Bioanorganische Chemie StiftstraBe 34-36 D-45470 MCu＇lheim an der Ruhr Germany Pflanzenphysiologie Justus-Liebig-Universita＇t SenckenbergstraBe 3 D-35390 Giessen Germany

Despite extensive study, the molecular structure of the chromophore-binding pocket of phytochrome A （phyA）, the principal photoreceptor controlling photomorphogenesis in plants, has not yet been successfully resolved. Here, we report a series of two-dimensional （2-D） magic-angle spinning solid-state NMR experiments on the recombi- nant N-terminal, 65-kDa PAS-GAF-PHY light-sensing module of phytochrome A3 from oat （Avena sativa）, assembled with uniformly 13C- and lSN-labeled phycocyanobilin （u-[13C,15N]-***3）. The Pr state of this protein was studied regarding the electronic structure of the chromophore and its interactions with the proximal amino acids. Using 2-D 13C-13C and 1HJSN experiments, a complete set of 13C and 15N assignments for the chromophore were obtained. Also, a large number of 1H-13C distance restraints between the chromophore and its binding pocket were revealed by inter- facial heteronuclear correlation spectroscopy. 13C doublings of the chromophore A-ring region and the C-ring carbox- ylate moiety, together with the observation of two Pr isoforms, Pr-I and Pr-II, demonstrate the local mobility of the chromophore and the plasticity of its protein environment. It appears that the interactions and dynamics in the binding pocket of phyA in the Pr state are remarkably similar to those of cyanobacterial phytochrome （Cphl）. The N-terminus of the region modeled （residues 56-66 of phyA） is highly mobile. Differences in the regulatory processes involved in plant and Cphl phytochromes are discussed.

关键词： solid-state NMR plant phytochrome chromophore-protein interaction signal transduction

Conception of a new 4-quadrant hydrogen compressed air energy storage power plant with an integrated electrolyzer

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Energy Reviews 2024年第3期3卷 92-101页

作者： Hans-Peter Beck Ann-Kathrin Klaas Christoph Klaas Research Center Energy Storage Technologies Clausthal University of TechnologyAm Stollen 19A38640GoslarGermany Institute of Electrical Power Engineering and Energy Systems Clausthal University of TechnologyLeibnizstraße 2838678Clausthal-ZellerfeldGermany

A hydrogen compressed air energy storage power plant with an integrated electrolyzer is ideal for large-scale,long-term energy storage because of the emission-free operation and the possibility to offer multiple ancillary services on the German energy *** paper defines analyzes such a storage concept and conducts an extensive comparison with four additional storage concepts based on various *** results show that the combination of storing compressed air and hydrogen offers a higher efficiency than storing only hydrogen and lower specific investment costs than storing only compressed *** result is confirmed with analysis of the optimal sizing of each power plant component for simultaneous participation on multiple energy markets with a linear optimization dispatch *** hydrogen compressed air energy storage(HCAES)power plant can utilize more revenue possibilities than a hydrogen energy storage because of the higher round-trip efficiency and the combination of the air compressor and the integrated electrolyzer during charging *** integration of the electrolyzer,however,offers a couple of challenges itself because of the highly flexible operation mode.A new concept for the controllable 24-pulse diode-thyristor rectifier of the electrolyzer is presented,that uses mostly common components while offering little to no grid harmonics and a long *** flexible integrated electrolyzer allows for the 4-quadrant operation of the storage power plant.

关键词： Long-term energy storage Hydrogen energy storage Compressed air energy storage Mixed-integer linear programming Electrolyzer 24-Pulse thyristor rectifier

Enhancing the performance of porous silicon biosensors:the interplay of nanostructure design and microfluidic integration

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Microsystems & Nanoengineering 2024年第4期10卷 211-224页

作者： Kayan Awawdeh Marc AButtkewitz Janina Bahnemann Ester Segal Faculty of Biotechnology and Food Engineering Technion—Israel Institute of Technology320003 HaifaIsrael Institute of Technical Chemistry Leibniz Universität Hannover30167 HannoverGermany Institute of Physics University of Augsburg86159 AugsburgGermany Centre for Advanced Analytics and Predictive Sciences(CAAPS) University of Augsburg86159 AugsburgGermany

This work presents the development and design of aptasensor employing porous silicon(PSi)Fabry‒Pérot thin films that are suitable for use as optical transducers for the detection of lactoferrin(LF),which is a protein biomarker secreted at elevated levels during gastrointestinal(GI)inflammatory disorders such as inflammatory bowel disease and chronic *** overcome the primary limitation associated with PSi biosensors—namely,their relatively poor sensitivity due to issues related to complex mass transfer phenomena and reaction kinetics—we employed two strategic approaches:First,we sought to optimize the porous nanostructure with respect to factors including layer thickness,pore diameter,and capture probe ***,we leveraged convection properties by integrating the resulting biosensor into a 3D-printed microfluidic system that also had one of two different micromixer architectures(i.e.,staggered herringbone micromixers or microimpellers)*** demonstrated that tailoring the PSi aptasensor significantly improved its performance,achieving a limit of detection(LOD)of 50 nM—which is>1 order of magnitude lower than that achieved using previously-developed biosensors of this ***,integration into microfluidic systems that incorporated passive and active micromixers further enhanced the aptasensor’s sensitivity,achieving an additional reduction in the LOD by yet another order of *** advancements demonstrate the potential of combining PSi-based optical transducers with microfluidic technology to create sensitive label-free biosensing platforms for the detection of GI inflammatory biomarkers.

关键词： porous integration fluid

Charge Transport in Disordered Graphene-Based Low Dimensional Materials

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Nano Research 2008年第5期1卷 361-394页

作者： Alessandro Cresti Norbert Nemec Blanca Biel Gabriel Niebler François Triozon Gianaurelio Cuniberti Stephan Roche CEA LETIMINATECF38054 GrenobleFrance CEA Institute for Nanoscience and CryogenicsINAC/SPSMS/GT17 rue des Martyrs38054 Grenoble Cedex 9France Theory of Condensed Matter Group Cavendish LaboratoryUniversity of CambridgeTrinity LaneCambridge CB217NUK Institute for Materials Science TU DresdenD-01062 DresdenGermany Department of Condensed Matter Physics Faculty of Mathematics and PhysicsCharles UniversityKe Karlovu 512116 Prague 2Czech Republic

Two-dimensional graphene,carbon nanotubes,and graphene nanoribbons represent a novel class of low dimensional materials that could serve as building blocks for future carbon-based *** these systems share a similar underlying electronic structure,whose exact details depend on confi nement effects,crucial differences emerge when disorder comes into *** this review,we consider the transport properties of these materials,with particular emphasis on the case of graphene *** summarizing the electronic and transport properties of defect-free systems,we focus on the effects of a model disorder potential(Anderson-type),and illustrate how transport properties are sensitive to the underlying *** provide analytical expressions for the elastic mean free path of carbon nanotubes and graphene nanoribbons,and discuss the onset of weak and strong localization regimes,which are genuinely dependent on the transport *** also consider the effects of edge disorder and roughness for graphene nanoribbons in relation to their armchair or zigzag orientation.

关键词： Graphene charge transport carbon nanotubes

Homo-& Heteroclinic Orbits in Conservative Systems with 3-wells Potential

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Northeastern Mathematical Journal 2002年第4期18卷 287-290页

作者：黄明游李松涛张凯李勇 Institute of Mathematics Jilin University Changchun 130012

Consider the following 2×2 nonlinear system:where f(u): R→R is a, smooth function. Setwhere F’(u)= f(u). Then (1) can be rewritten as an equivalent Hamiltonian system:

关键词： conservative systems 3-wells potential homoclinic and heteroclinicorbits

Modeling height–diameter relationship for Populus euphratica in the Tarim riparian forest ecosystem, Northwest China

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Journal of Forestry Research 2016年第4期27卷 889-900页

作者： Tayierjiang Aishan Umüt Halik Florian Betz Philipp Gartner Bernd Cyffka Key Laboratory of Oasis Ecology College of Resources &Environmental Sciences Xijiiang UniversityUrumqi 830046 China Faculty of Mathematics and Geography Catholic University of Eichstaett-Ingolstadt 85072 Eichstaett Germany Geoinformation in Environmental Planning Lab Technical University of Berlin 10623 Berlin Germany

Modeling height–diameter relationships is an important component in estimating and predicting forest development under different forest management scenarios. In this paper, ten widely used candidate height–diameter models were fitted to tree height and diameter at breast height（DBH）data for Populus euphratica Oliv. within a 100 ha permanent plots at Arghan Village in the lower reaches of the Tarim River, Xinjiang Uyghur Autonomous Region of China. Data from 4781 trees were used and split randomly into two sets：75 % of the data were used to estimate model parameters（model calibration）, and the remaining data（25 %） were reserved for model validation. All model performances were evaluated and compared by means of multiple model performance criteria such as asymptotic t-statistics of model parameters, standardized residuals against predicted height,root mean square error（RMSE）, Akaike’s informationcriterion（AIC）, mean prediction error（ME） and mean absolute error（MAE）. The estimated parameter a for model（6） was not statistically significant at a level of a = 0.05. RMSE and AIC test result for all models showed that exponential models（1）,（2）,（3） and（4） performed significantly better than others. All ten models had very small MEs and MAEs. Nearly all models underestimated tree heights except for model（6）. Comparing the MEs and MAEs of models, model（1） produced smaller MEs（0.0059） and MAEs（1.3754） than other models. To assess the predictive performance of models, we also calculated MEs by dividing the model validation data set into 10-cm DBH classes. This suggested that all models were likely to create higher mean prediction errors for tree DBH classes[20 cm. However, no clear trend was found among ***（6） generated significantly smaller mean prediction errors across all tree DBH classes. Considering all the aforementioned criteria, model（1）： TH ？ 1：3 t a= e1 t b？eàc？DBHT and model（6）： TH ？ 1：3 t DBH2= ea t b？DBH t c ？ DBH2T are recommended as suitable models for de

关键词： calibration shortcomings absolute dividing exponential fitting candidate permanent fitted estimating

Extracting the low-energy constant L_(0)^(r)at three flavors from pion-kaon scattering

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Communications in Theoretical Physics 2022年第6期74卷 61-65页

作者： Chaitra Kalmahalli Guruswamy Ulf-G Meißner Chien-Yeah Seng Helmholtz-Institut für Strahlen-und Kernphysik and Bethe Center for Theoretical Physics Universität BonnD-53115 BonnGermany Institute for Advanced Simulation Institut für Kernphysik and Jülich Center for Hadron PhysicsForschungszentrum JülichD-52425 JülichGermany Tbilisi State University 0186 TbilisiGeorgia

based on our analysis of the contributions from the connected and disconnected contraction diagrams to the pion-kaon scattering amplitude,we provide the first determination of the only free low-energy constant at O(p^(4)),known as L_(0)^(r),in SU(4|1)Partially-Quenched Chiral Perturbation theory using the data from the Extended Twisted Mass collaboration,L_(0)^(r)(μ=M_(ρ))=0.77(20)(25)(7)(7)(2)·10^(-3).The theory uncertainties originate from the unphysical scattering length,the physical low-energy constants,the higher-order chiral corrections,the(lattice)meson masses and the pion decay constant,respectively.

关键词： lattice QCD partially quenched chiral perturbation theory pion-kaon scattering

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

A Study on the Correlation Between Poles and Cuts in ππ Scattering

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Communications in Theoretical Physics 2019年第11期71卷 1309-1318页

作者： Ling-Yun Dai Xian-Wei Kang Tao Luo School of Physics and Electronics Hunan University College of Nuclear Science and Technology Beijing Normal University Key Laboratory of Nuclear Physics and Ion-beam Application(MOE) and Institute of Modern Physics Fudan University Helmholtz Institut für Strahlen-und Kernphysik and Bethe Center for Theoretical Physics Universit?t Bonn Institute for Advanced Simulation Institut f¨ur Kernphysik and Jülich Center for Hadron Physics Forschungszentrum Jülich

In this paper we propose a dispersive method to describe two-body scattering with unitarity imposed. This approach is applied to elastic ππ scattering. The amplitudes keep single-channel unitarity and describe the experimental data well, and the low-energy amplitudes are consistent with that of chiral perturbation theory. The pole locations of the σ, f0(980), ρ(770) and f2(1270) and their couplings to ππ are obtained. A virtual state appearing in the isospin-two S-wave is confirmed. The correlations between the left(and right) hand cut and the poles are discussed. Our results show that the poles are more sensitive to the right hand cut rather than the left hand cut. The proposed method could be used to study other two-body scattering processes.

关键词： dispersion relations partial-wave analysis chiral lagrangian meson production