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Glycolytic Shunts Replenish the calvin-Benson-Bassham cycle as Anaplerotic Reactions in cyanobacteria

Molecular Plant 2020年第3期13卷 471-482页

作者： Alexander Makowka Lars Nichelmann dennis Schulze Katharina Spengler christoph Wittmann Karl Forchhammer Kirstin Gutekunst Department of Biology Botanical InstituteUniversity Kiel24118 KielGermany Institute for Systems Biotechnology Saarland University66123 SaarbruckenGermany Organismic Interactions Department Interfaculty Institute for Microbiology and Infection MedicineUniversity

The recent discovery of the Entner-Doudoroff(ED)pathway as a third glycolytic route beside Embden-Meyerhof-Parnas(EMP)and oxidative pentose phosphate(OPP)pathway in oxygenic photoautotrophs requires a revision of their central carbohydrate *** this study,unexpectedly,we observed that deletion of the ED pathway alone,and even more pronounced in combination with other glycolytic routes,diminished photoautotrophic growth in continuous light in the cyanobacterium Synechocystis *** ***,we found that the ED pathway is required for optimal glycogen catabolism in parallel to an operating calvin-Benson-Bassham(cBB)*** is counter-intuitive that glycolytic routes,which are a reverse to the cBB cycle and do not provide any additional biosynthetic intermediates,are important under photoautotrophic ***,observations on the ability to reactivate an arrested cBB cycle revealed that they form glycolytic shunts that tap the cellular carbohydrate reservoir to replenish the *** together,our results suggest that the classical view of the cBB cycle as an autocatalytic,completely autonomous cycle that exclusively relies on its own enzymes and c02 fixation to regenerate ribulose-1,5-bisphosphate for Rubisco is an *** propose that in common with other known autocatalytic cycles,the cBB cycle likewise relies on anaplerotic reactions to compensate for the depletion of intermediates,particularly in transition states and under fluctuating light conditions that are common in nature.

关键词： central carbohydrate metabolism calvin-Benson-Bassham cycle Entner-Doudoroff pathway oxidative pentose phosphate pathway Embden-Meyerhof-Parnas pathway cyanobacteria

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Magnetic resonance studies of jets in a gas-solid fluidised bed

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Particuology 2012年第2期10卷 161-169页

作者： Meenal Pore Thusara c. chandrasekera Daniel J. Holland Aining Wang Fei Wang Qussai Marashdeh Michael D. Mantle Andrew J. Sederman Liang-Shih Fan Lynn F. Gladden John S. dennis Department of chemical Engineering and Biotechnology University of Cambridge Pembroke Street Cambridge CB2 3RA United Kingdom The William G. Lowrie Department of chemical and Biomolecular Engineering Ohio State University Columbus OH 43210 USA

Magnetic resonance imaging （MRI） has been used to study the behaviour Of jets at the distributor of a 50 mm diameter fluidised bed of 0.5 mm diameter poppy seeds. Two perforated-plate distributors were examined, containing either 10 or 14 holes, each 1 mm diameter. Ultra-fast MR imaging was able to show the transient nature of the upper parts of the jets, where discrete bubbles are formed. Imaging in 3D showed that the central jets were the longest for flow rates below minimum fluidisation. Above minimum fluidisation, the outer jets, nearest the wall of the fluidised bed, arched inward towards the central axis. In this latter case, interpretation of the time-averaged 3D image required the use of ultra-fast MR imaging to identify the approximate height above the distributor at which discrete bubbles were formed. The apparently continuous void extending along the central axis above this height in the time-averaged 3D image was thus identified, using ultra-fast MR imaging, as representing the averaged paths of released bubbles. Time-averaged MR velocity mapping was also used to identify dead zones of stationary particles resting on the distributor between the jets. The dead zones could be observed when the superficial velocity of the gas approached minimum fluidisation, but they were smaller than those observed at lower gas superficial velocity. comparable images of a single jet through 1.2 mm diameter poppy seeds from MRI and electrical capacitance volume tomography （EcVT） are also demonstrated.

关键词： Fluidised bedMRIEcVTJetsDistributor design

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Degradation study on tin- and bismuth-based gas-diffusion electrodes during electrochemical cO_(2) reduction in highly alkaline media

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Journal of Energy chemistry 2021年第11期30卷 367-376,I0008页

作者： Fabian Bienen Armin Lowe Joachim Hildebrand Sebastian Hertle Dana Schonvogel dennis Kopljar Norbert Wagner Elias Klemm Kaspar Andreas Friedrich Institute of Engineering Thermodynamics German Aerospace CenterPfaffenwaldring 38-4070569 StuttgartGermany Institute of Building Energetics Thermal Engineering and Energy StorageUniversity of StuttgartPfaffenwaldring 3170569 StuttgartGermany Institute of Technical chemistry University of StuttgartPfaffenwaldring 5570569 StuttgartGermany Institute of Engineering Thermodynamics German Aerospace CenterCarl-von-Ossietzky-Straße 1526129 OldenburgGermany

This work investigated the degradation of tin – based gas-diffusion electrodes (GDE) and also a promising Bi2O3 GDE in electrochemical cO_(2) reduction in highly alkaline media which has not been studied before. The contributions of the electrode wetting (or flooding, if excessively) and catalyst leaching on the degradation were analyzed. Therefore, electrochemical impedance spectroscopy was used to monitor the wetted surface area of the GDE in combination with post-mortem analysis of the penetration depth by visualizing the electrolyte’s cation in the GDE cross-section. Furthermore, to reveal a possible degradation of the electrocatalyst, its distribution was mapped in the GDEs cross-section after operation while the catholyte was additionally analyzed via IcP-MS. The results clearly demonstrate that the SnO_(2) catalyst dissolves in the reaction zone inside the GDE and might be partially redeposited near the GDEs surface. Since the redeposition process occurs only partially a steady loss of catalyst was observed impeding a clear distinction of the two degradation phenomena. Nevertheless, the deterioration of the electrode performance measured as faraday efficiency (FE) of the parasitic hydrogen evolution reaction (HER) qualitatively correlates with the differential double layer capacitance (cdl). A significant difference of the rate of increase for the hydrogen FE and cdl can be ascribed to the superposition of both above-mentioned degradation mechanisms. The demonstrated instability of SnO_(2) contrasts with the behavior of Bi2O3 GDE which is stabilized during cO_(2) conversion by redeposition of the diluted dissolved species as metallic Bi which is active for the cO_(2) reduction reaction.

关键词： Electrochemical cO_(2)reduction Heterogeneous catalysis Gas-diffusion electrode Electrochemical impedance spectroscopy catalyst leaching

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Histone Acetylation, VERNALIZATION INSENSITIVE 3, FLOWERING LOcUS c, and the Vernalization Response

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Molecular Plant 2009年第4期2卷 724-737页

作者： Donna M. Bond Elizabeth S. dennis Barry J. Pogson E. Jean Finnegan cSIRO Plant Industry Canberra Australia ARc centre of Excellence in Plant Energy Biology School of Biochemistry and Molecular Biology Australian National University Canberra Australia

The quantitative induction of VIN3 by low temperatures is required for PRc2 repression of FLc and promotion of flowering （vernalization） in Arabidopsis. Histone acetylation, a chromatin modification commonly associated with gene transcription, increased on VIN3 chromatin in two spatially and temporally distinct phases in response to low temperatures. During short-term cold exposure, histone H3 acetylation at the transcription start site rapidly increased, implying that it is required for VlN3 induction. Subsequent changes in histone H3 and H4 acetylation occurred following continued VIN3 transcription during prolonged cold exposure. Members of the SAGA-like transcriptional adaptor complex, including the histone acetyltransferase GcNS, which induces expression of the cold acclimation pathway genes, do not regulate VlN3 induction during cold exposure, indicating that the cold acclimation pathway and the cold-induction of VlN3 are regulated by different transcriptional mechanisms. Mutations in the other 11 histone acetyltransferase genes did not affect VlN3 induction. However, nicotinamide, a histone deacetyiase inhibitor, induced VIN3 and altered histone acetylation at the VIN3 locus. VIN3 induction was proportional to the length of nicotinamide treatment, which was associated with an early-flowering phenotype and repression of FLc. However, unlike vernalization, the repression of FLc was independent of VIN3 activity. Nicotinamide treatment did not cause a change in the expression of any genes in the autonomous pathway or members of the PRc2 complex, the well characterized repressors of FLc. Our data suggest that FLc is repressed via a novel pathway involving the SIR2 class of histone deacetylases.

关键词： cold acclimation histone acetyltransferase histone deacetylase SIR2 nicotinamide.

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Bleeding outcomes after non-emergency percutaneous coronary intervention in the very elderly

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Journal of Geriatric cardiology 2017年第10期14卷 624-631页

作者： Vimalraj Bogana Shanmugam dennis T Wong Hashrul Rashid James D cameron Yuvaraj Malaiapan Peter J Psaltis Monash cardiovascular Research centre Clayton Campus of Monash University Victoria Australia South Australian Health and Medical Research Institute Adelaide Australia

Background Octogenarians constitute an increasing proportion of patients presenting for non-emergency percutaneous coronary intervention （PcI）. Methods This study evaluated the in-hospital procedural characteristics and outcomes, including the bleeding events of 293 octogenarians presenting between January 2010 and December 2012 for non-emergency PcI to a single large volume tertiary care Aus- tralian center. comparisons were made with 293 consecutive patients aged less than or equal to 60 years, whose lesions were matched with the octogenarians. Results Non-ST elevation myocardial infarction was the most frequent indication for non-emergency PcI in octoge- narians. compared to the younger cohort, they had a higher prevalence of co-morbidities and more complex coronary disease, comprising more type c and calcified lesions. Peri-procedural use of low molecular weight heparin （LMWH; 1.0% vs. 5.8%; P 〈 0.001） and glycopro- tein IIb/IIIa inhibitors （2.1% vs. 9.6%; P 〈 0.001） was lower, while femoral arterial access was used more commonly than in younger patients （80.9% vs. 67.6%; P 〈 0.001）. Overall, there was a non-significant trend towards higher incidence of all bleeding events in the elderly （9.2% vs. 5.8%; P = 0.12）. There was no significant difference in access site or non-access site bleeding and major or minor bleeding between the two cohorts. Sub-analysis did not reveal any significant influence on bleeding rates by the use of LMWH, glycoprotein IIb/IIIa inhibitors or femoral arterial access. In addition, there were no significant differences in the rates of in-hospital mortality, stroke or acute stent thrombosis between the two groups. conclusions In this single center study, we did not observe significant increases in adverse in-hospital outcomes including the incidence of bleeding in octogenarians undergoing non-emergency PcI.

关键词： Bleeding coronary artery disease Octogenarians Percutaneous coronary intervention

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一个支持战略管理的电子会议系统的评估

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计算机工程与应用 1991年第5期27卷 32-47页

作者： A.R.dennis c.K.Tyran 刘小敬国家教委信息中心

战略管理被定义为制定和实现组织机构的战略目标、政策和计划的全过程。它是一项由一组管理人员完成的重要的组织任务。尽管信息技术早已被用来支持战略管理,但只是在最近才通过提供电子会议系统(EMS)这样的手段支持战略管理的群体过程... 详细信息

战略管理被定义为制定和实现组织机构的战略目标、政策和计划的全过程。它是一项由一组管理人员完成的重要的组织任务。尽管信息技术早已被用来支持战略管理,但只是在最近才通过提供电子会议系统(EMS)这样的手段支持战略管理的群体过程。一个EMS能够通过提供过程支持、过程结构、任务结构和任务支持影响会议的进行。过程支持改善群体成员之间的相互沟通(通过一个电子通讯渠道)。过程结构指导讨论的形式和内容(通过一个议程日程表)任务结构指利用结构化的技术分析任务(一个数学或概念模型)。任务支持是指没有附加结构的(如数据库或计算器)信息的提供使用或计算支持。这篇论文的目的是评估EMS支持决策管理的能力。17个实例的研究结构表明EMS技术的使用,能够加强6种能力,已往的研究已经认为这些能力与促进战略管理的成功有关系。过程支持和过程结构对成功来说比任务结构和任务支持更重要。对不那么成功的会议的分析表明群体的领导和会议的组织者和会议的参加者之间缺少交流沟通和特定的外部环境的减弱是失败的主要原因。

关键词：战略管理电子会议系统

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An Application of Bayesian Inference on the Modeling and Estimation of Operational Risk Using Banking Loss Data

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Applied Mathematics 2014年第6期5卷 862-876页

作者： Kashfia N. Rahman dennis A. Black Gary c. McDonald Oakland University Rochester USA omerica Bank Dallas USA

Bayesian inference method has been presented in this paper for the modeling of operational risk. Bank internal and external data are divided into defined loss cells and then fitted into probability distributions. The distribution parameters and their uncertainties are estimated from posterior distributions derived using the Bayesian inference. Loss frequency is fitted into Poisson distributions. While the Poisson parameters, in a similar way, are defined by a posterior distribution developed using Bayesian inference. Bank operation loss typically has some low frequency but high magnitude loss data. These heavy tail low frequency loss data are divided into several buckets where the bucket frequencies are defined by the experts. A probability distribution, as defined by the internal and external data, is used for these data. A Poisson distribution is used for the bucket frequencies. However instead of using any distribution of the Poisson parameters, point estimations are used. Monte carlo simulation is then carried out to calculate the capital charge of the in- ternal as well as the heavy tail high profile low frequency losses. The output of the Monte carlo simulation defines the capital requirement that has to be allocated to cover potential operational risk losses for the next year.

关键词： Monte carlo Simulation Value-at-Risk Basel II Operational Risk Bayesian

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Submerged flexible vegetation impact on open channel flow velocity distribution: An analytical modelling study on drag and friction

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Water Science and Engineering 2019年第2期12卷 121-128页

作者： Jaan H. Pu Awesar Hussain Ya-kun Guo Nikolaos Vardakastanis Prashanth R. Hanmaiahgari dennis Lam Faculty of Engineering and Informatics University of BradfordBradford BD7 1DPUK Department of civil Engineering Indian Institute of TechnologyKharagpur 721302India

In this paper,an analytical model that represents the streamwise velocity distribution for open channel flow with submerged flexible vegetation is *** the present vegetated flow modelling,the whole flow field has been separated into two layers vertically: a vegetated layer and a non-vegetated free-water *** the vegetated layer,an analysis of the mechanisms affecting water flow through flexible vegetation has been *** the non-vegetated layer,a modified log-law equation that represents the velocity profile varying with vegetation height has been *** on the studied analytical model,a sensitivity analysis has been conducted to assess the influences of the drag (cD) and friction (cf ) coefficients on the flow *** investigated ranges of cD and cf have also been compared to published *** findings suggest that the cD and cf values are non-constant at different depths and vegetation densities,unlike the constant values commonly suggested in *** phenomenon is particularly clear for flows with flexible vegetation,which is characterised by large deflection.

关键词： Analytical model Flexible vegetation Flow velocity Friction Drag Submerged vegetation

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c-Terminus-Mediated Voltage Gating of Arabidopsis Guard cell Anion channel QUAc1

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Molecular Plant 2013年第5期6卷 1550-1563页

作者： Patrick Mumm dennis Imes Enrico Martinoia Khaled A.S. AI-Rasheid Dietmar Geiger Irene Marten Rainer Hedrich Institute for Molecular Plant Physiology and Biophysics University of Wurzburg Julius-von-Sachs Platz 2 D-97082 Wurzburg Germany Institute of Plant Biology University of Zurich Zollikerstrasse 107 Zurich Switzerland King Saud University Zoology Department College of Science PO Box 2455 Riyadh 11451 Saudi Arabia

Anion transporters in plants play a fundamental role in volume regulation and signaling. currently, two plasma membrane-located anion channel familiesmSLAc/SLAH and ALMTmare known. Among the ALMT family, the root-expressed ALuminium-activated Malate Transporter 1 was identified by comparison of aluminum-tolerant and Al3＋-sensitive wheat cultivars and was subsequently shown to mediate voltage-independent malate currents. In con- trast, ALMT12/QUAc1 （QUickly activating Anion channel1） is expressed in guard cells transporting malate in an Al3＋- insensitive and highly voltage-dependent manner. So far, no information is available about the structure and mechanism of voltage-dependent gating with the QUAc1 channel protein. Here, we analyzed gating of QUAcl-type currents in the plasma membrane of guard cells and QUAcl-expressing oocytes revealing similar voltage dependencies and activation- deactivation kinetics. In the heterologous expression system, QUAc1 was electrophysiologically characterized at increas- ing extra- and intracellular malate concentrations. Thereby, malate additively stimulated the voltage-dependent QUAc1 activity. In search of structural determinants of the gating process, we could not identify transmembrane domains com- mon for voltage-sensitive channels. However, site-directed mutations and deletions at the c-terminus of QUAc1 resulted in altered voltage-dependent channel activity. Interestingly, the replacement of a single glutamate residue, which is con- served in ALMT channels from different clades, by an alanine disrupted QUAc1 activity. Together with c- and N-terminal tagging, these results indicate that the cytosolic c-terminus is involved in the voltage-dependent gating mechanism of QUAc1.

关键词： c-terminal deactivation R-type/QUAc-type anion channel single-channel conductance gating modifier.

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Salt Accumulation and Physiology of Naturally Occurring Grasses in Saline Soils in Australia

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Pedosphere 2015年第4期25卷 501-511页

作者： Mohammad S.I.BHUIYAN Anantanarayanan RAMAN dennis S.HODGKINS David MITcHELL Helen I.NIcOL Soil Research Group Charles Sturt University Graham centre for Agricultural Innovation Orange Agricultural Institute NSW Department of Primary Industries

Salinity is a major soil contamination problem in Australia. To explore salinity remediation, we evaluated the concentrations of sodium （Na）, potassium （K）, magnesium （Mg）, and calcium （ca） in roots and shoots and in the supporting soil of the naturally occurring grasses, cynodon dactylon and Thinopyrurn ponticum, at two salt-affected sites, Gumble and cundumbul in central-western New South Wales, Australia. The physiological parameters of the two grass species, including net photosynthetic rate （Pn）, stomatal conductance （gs）, and intercellular cO2 concentration （ci）, were investigated using one mature leaf from c. dactylon and T. ponticum populations. Increasing salinity levels in the topsoil had a significant influence on ci and gs, whereas no significant effect occurred on Pn in c. dactylon and T. ponticum. The Pn values in c. dactylon and T. ponticum were greater at cundumbul than at Gumble. The greater Mg concentration facilitated greater Pn in c. dactylon and T. ponticum populations at cundumbul than Gumble. With increasing salinity levels in the soil, Na accumulation increased in c. dactylon and T. ponticum. The ratio between K and Na was ~ 1 in roots and shoots of both populations irrespective of the sites. Bioaccumulation factor （BF） and translocation factor （TF） results revealed that K and Na translocations were significantly higher in T. ponticum than in c. dactylon, whereas ca and Mg translocations were significantly higher in c. dactylon than in T. ponticum. Accumulation of Na, K, Mg, and ca ions was higher in T. ponticum than in c. dactylon; therefore, we suggest that T. ponticum as a greater salt accumulator than c. dactylon could be used for revegetation and phytoremediation of the salt-affected soils.

关键词： bioaccumulation factor intercellular cO2 concentration net photosynthetic rate phytoremediation revegetation soilcontamination stomatal conductance translocation factor

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