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Adjustment of Forest Ecosystem Root Respiration as Temperature Warms

Journal of Integrative Plant Biology 2008年第11期50卷 1467-1483页

作者： Andrew J.Burton Jerry M.Melillo serita d.frey Ecosystem Science Center Michigan Technological University School of Forest Resources and Environmental Science Michigan Technological University The Ecosystems Center Marine Biological Laboratory department of Natural Resources University of New Hampshire

Adjustment of ecosystem root respiration to warmer climatic conditions can alter the autotrophic portion of soil respiration and influence the amount of carbon available for biomass production. We examined 44 published values of annual forest root respiration and found an increase in ecosystem root respiration with increasing mean annual temperature （MAT）, but the rate of this cross-ecosystem increase （Q10 = 1.6） is less than published values for short-term responses of root respiration to temperature within ecosystems （Q10 = 2-3）. When specific root respiration rates and root biomass values were examined, there was a clear trend for decreasing root metabolic capacity （respiration rate at a standard temperature） with increasing MAT. There also were tradeoffs between root metabolic capacity and root system biomass, such that there were no instances of high growing season respiration rates and high root biomass occurring together. We also examined specific root respiration rates at three soil warming experiments at Harvard Forest, USA, and found decreases in metabolic capacity for roots from the heated plots. This decline could be due to either physiological acclimation or to the effects of co-occurring drier soils on the measurement date. Regardless of the cause, these findings clearly suggest that modeling efforts that allow root respiration to increase exponentially with temperature, with Q10 values of 2 or more, may over-predict root contributions to ecosystem CO2 efflux for future climates and underestimate the amount of C available for other uses, including net primary productivity.

关键词： acclimation climatic warming root biomass root respiration soil warming.

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Fast jet proper motion discovered in a blazar at z=4.72

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Science Bulletin 2020年第7期65卷 525-530,M0003页

作者： Yingkang Zhang Tao An Sándor frey Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Radio Astronomy Chinese Academy of SciencesNanjing 210008China Konkoly Observatory Research Centre for Astronomy and Earth SciencesKonkoly Thege Miklósút 15-17H-1121 BudapestHungary

High-resolution observations of high-redshift(z > 4) radio quasars offer a unique insight into jet kinematics at early cosmological epochs, as well as constraints on cosmological model *** to the general weakness of extremely distant objects and the apparently slow structural changes caused by cosmological time dilation, only a couple of high-redshift quasars(HRQs) have been studied with parsec-scale resolutions, and with limited number of observing epochs. Here we report on very long baseline interferometry(VLBI) observations of a high-redshift blazar J1430 + 4204(z=4.72) in the 8 GHz frequency band at five different epochs spanning 22 years. The source shows a compact core–jet structure with two jet components being identified within 3 milli-arcsecond(mas) scale. The long time span and multiple-epoch data allow for the kinematic studies of the jet components. That results in a jet proper motion of μ(J1) = 0.017 ± 0.002 mas a^-1 and μ(J2) = 0.156 ± 0.015 mas a^-1, respectively. For the fastest-moving outer jet component J2, the corresponding apparent transverse speed is (19.5 ± 1.9) *** inferred bulk jet Lorentz factor C=14.6 ± 3.8 and viewing angle θ=2.2°± 1.6°indicate highly relativistic beaming. The Lorentz factor and apparent proper motion are the highest measured to date among the z > 4 jetted radio sources, while the jet kinematics is still consistent with the cosmological interpretation of quasar redshifts.

关键词： Nuclei High-redshift Radio continuum Quasars Individual J1430+4204

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Nickela-electrocatalyzed sulfide and phosphine oxygenations with water

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Science China Chemistry 2021年第6期64卷 873-874页

作者： Long Yang Johanna frey Lutz Ackermann Institut für Organische und Biomolekulare Chemie Georg-August-Universität GöttingenTammannstrasse 2Göttingen 37077Germany Wöhler Research Institute for Sustainable Chemistry(WISCh) Georg-August-Universität GöttingenTammannstrasse 2Göttingen 37077Germany

Molecular electrochemistry has emerged as an environmentally-friendly *** major recent momentum was gained in electrocatalyzed bond activations by earth-abundant 3 d transition metals[1],cost-effective nickela-electrocatalysis continuous to be underdevelopment for electrocatalysis[2].Nickel is an essential component of metalloproteins involved in catalytic aerobic oxygenation processes,for which nickel-dioxygen species were proposed as the key catalytic species[3].

关键词： catalyzed nickel Nickel

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An Update on Abscisic Acid Signaling in Plants and More

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Molecular Plant 2008年第2期1卷 198-217页

作者： Aleksandra Wasilewsk.a Florina Vlad Caroline Sirichandra Yulia Redko Fabien Jammes Christiane Valon Nicolas Frei dit frey Jeffrey Leung Institut des Sciences du Vegetal Centre National de la Recherche Scientifique UPR 23551 Avenue de la Terrasse Bat. 23 91190 Gif-sur-Yvette France CNRS UPR9073 Institut de Biologie Physico-Chimique 13 rue Pierre et Marie Curie 75005 Paris France Laboratoire Signalisation et Regulation Coordonnee du Metabolisme Carbone et Azote Institut de Biotechnologie des Plantes (UMR8618) Universite Paris-Sud F-91405 Orsay Cedex France

The mode of abscisic acid （ABA） action, and its relations to drought adaptive responses in particular, has been a captivating area of plant hormone research for much over a decade. The hormone triggers stomatal closure to limit water loss through transpiration, as well as mobilizes a battery of genes that presumably serve to protect the cells from the ensuing oxidative damage in prolonged stress. The signaling network orchestrating these various responses is, however, highly complex. This review summarizes several significant advances made within the last few years. The biosynthetic pathway of the hormone is now almost completely elucidated, with the latest identification of the ABA4 gene encoding a neoxanthin synthase, which seems essential for de novo ABA biosynthesis during water stress. This leads to the interesting question on how ABA is then delivered to perception sites. In this respect, regulated transport has attracted renewed focus by the unexpected finding of a shoot-to-root translocation of ABA during drought response, and at the cellular level, by the identification of a B-galactosidase that releases biologically active ABA from inactive ABA-glucose ester. Surprising candidate ABA receptors were also identified in the form of the Flowering Time Control Protein A （FCA） and the Chloroplastic Magnesium Protoporphyrin-IX Chelatase H subunit （CHLH） in chloroplast-nucleus communication, both of which have been shown to bind ABA in vitro. On the other hand, the protein（s） corresponding to the physiologically detectable cell-surface ABA receptor（s） is （are） still not known with certainty. Genetic and physiological studies based on the guard cell have reinforced the central importance of reversible phosphorylation in modulating rapid ABA responses. Sucrose Non-Fermenting Related Kinases （SnRK）, Calcium-dependent Protein Kinases （CdPK）, Protein Phosphatases （PP） of the 2C and 2A classes figure as prominent regulators in this single-cell model. Identifying their d

关键词： Abscisic Acid Signaling Plants and More

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恶性胶质瘤抗血管生成治疗现状

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中国现代神经疾病杂志 2008年第5期8卷 403-410页

作者： frey d Czabanka M Vajkoczy P 刘辉杨学军德国柏林大学Charité医院神经外科天津医科大学总医院神经外科 300052

血管生成，即从已存在的微血管系统中生成新的血管，在生理状态及肿瘤生长过程中均可发生。在生理状态下，血管生成过程在胚胎发育、胎儿出生后及女性生殖周期中是不可或缺的。而且，血管生成亦是伤口充分愈合的重要因素。过去数年内，... 详细信息

血管生成，即从已存在的微血管系统中生成新的血管，在生理状态及肿瘤生长过程中均可发生。在生理状态下，血管生成过程在胚胎发育、胎儿出生后及女性生殖周期中是不可或缺的。而且，血管生成亦是伤口充分愈合的重要因素。过去数年内，血管生成机制是研究的焦点，业已证实血管生成是由血管生成因子和抗血管生成因子所调控。当肿瘤生长时这些因子的均衡性被打破，这种不平衡是由于肿瘤细胞过多地产生血管生成因子，

关键词：抗血管生成治疗恶性胶质瘤抗血管生成因子女性生殖周期生理状态肿瘤生长微血管系统生长过程

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Formation of tholeiitic basalts by lithosphere-asthenosphere interaction: example from datong, North China

Formation of tholeiitic basalts by lithosphere-asthenosphere...

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2006年全国岩石学与地球动力学研讨会

作者： Frederick A．frey Mark d．Feigenson department of Earth Atmospheric and Planetary Sciences MITCambridge MA 02139 department of Geological Sciences Rutgers University 610 Taylor RoadPiscatawayNJ08854USA

The geochemistry of Quaternary volcanic rocks from datong provides important constraints on the petrogenesis of continental alkali and tholeiitic basalts and lithospheric evolution in the western North China Craton. Alkali basalts in north datong have trace element compositions similar to oceanic island basalts (OIB) . They show nearly homogenous isotopic compositions ( ε Nd=5.4-6.8 and 87Sr/86 Sr=0.7035-0.7037) that resemble the nearby Hannuoba Miocene basalts,

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Introducing the Open Energy Ontology: Enhancing data interpretation and interfacing in energy systems analysis

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能源与人工智能(英文) 2021年第3期5卷 53-66页

作者： Meisam Booshehri Lukas Emele Simon Flügel Hannah Förster Johannes frey Ulrich frey Martin Glauer Janna Hastings Christian Hofmann Carsten Hoyer-Klick Ludwig Hülk Anna Kleinau Kevin Knosala Leander Kotzur Patrick Kuckertz Till Mossakowski Christoph Muschner Fabian Neuhaus Michaja Pehl Martin Robinius Vera Sehn Mirjam Stappel Institute for Applied Ecology BerlinGermany Institute for Applied Informatics(InfAI)/Leipzig University Germany department of Energy Systems Analysis Institute of Networked Energy SystemsGerman Aerospace Center(DLR)StuttgartGermany Faculty of Computer Science Otto-von-Guericke-Universität MagdeburgGermany Reiner Lemoine Institut BerlinGermany Institute of Techno-economic Systems Analysis(IEK-3) Forschungszentrum JülichJülichGermany Institute of Energy Economics and Rational Energy Use University of StuttgartGermany Potsdam Institute for Climate Impact Research PotsdamGermany Fraunhofer Institute for Energy Economics and Energy System Technology KasselGermany

Heterogeneous data,different definitions and incompatible models are a huge problem in many domains,with no exception for the field of energy systems ***,it is hard to re-use results,compare model results or couple models at *** provide a precisely defined vocabulary to build a common and shared conceptu-alisation of the energy ***,we present the Open Energy Ontology(OEO)developed for the domain of energy systems *** the OEO provides several benefits for the ***,it enables consistent annotation of large amounts of data from various research *** example is the Open Energy Platform(OEP).Adding such annotations makes data semantically searchable,exchangeable,re-usable and ***,computational model coupling becomes much *** advantages of using an ontology such as the OEO are demonstrated with three use cases:data representation,data annotation and interface *** also describe how the ontology can be used for linked open data(LOd).

关键词： Collaborative ontology development Linked open data Metadata annotation Energy systems analysis

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The ABA-deficiency Suppressor Locus HAS2 Encodes the PPR Protein LOI1/MEF11 Involved in Mitochondrial RNA Editing

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Molecular Plant 2015年第4期8卷 644-656页

作者： Julien Sechet Camille Roux Anne Plessis delphine Effroy Anne frey Francois Perreau Catherine Biniek Anja Krieger-Liszkay david Macherel Helen M. North Hakim Mireau Annie Marion-Poll INRA Institut Jean-Pierre Bourgin UMR 1318 ERL CNRS 3559 Saclay Plant Sciences RD10 F-78026 Versailles France AgroParisTech Institut Jean-Pierre Bourgin UMR 1318 ERL CNRS 3559 Saclay Plant Sciences RD10 F-78026 Versailles France CEA Saclay IBiTec-S CNRS UMR 8221 Serv Bioenerget Biol Struct & Mecanisme F-91191 Gif Sur Yvette France Universite d'Angers UMR IRHS 1345 INRA Agrocampus Ouest F-49045 Angers France Institut Jean-Pierre Bourgin INRA Bat 2 F-78026 Versailles Cedex France Institut Jean-Pierre Bourgin INRA Bat 7 F-78026 Versailles Cedex France department of Biology New York University 1009 Main Building 100 Washington Square East New York NY 10003-6688 USA

The hotABA-deficiency suppressor2 （has2） mutation increases drought tolerance and the ABA sensitivity of stomata closure and seed germination. Here we report that the HAS2 locus encodes the MITOCHONdRIAL EdITING FACTOR11 （MEF11）, also known as LOVASTATIN INSENSITIVE1. has21mef11 mutants exhibited phenotypes very similar to the ABA-hypersensitive mutant, hail-1 pp2ca-1 hab 1-1 abil-2, which is impaired in four genes encoding type 2C protein phosphatases （PP2C） that act as upstream negative regulators of the ABA signaling cascade. Like pp2c, mef11 plants were more resistant to progressive water stress and seed germination was more sensitive to paclobutrazol （a gibberellin biosynthesis inhibitor） as well as mannitol and NaCI, compared with the wild-type plants. Phenotypic alterations in mef11 were associated with the lack of editing of transcripts for the mitochondrial cytochrome c maturation FN2 （cCmFN2） gene, which encodes a cytochrome c-heme lyase subunit involved in cytochrome c biogenesis. Although the abundance of electron transfer chain complexes was not affected, their dysfunction could be deduced from increased respiration and altered production of hydrogen peroxide and nitric oxide in reef11 seeds. As minor defects in mitochondrial respiration affect ABA signaling, this suggests an essential role for ABA in mitochondrial retrograde regulation.

关键词： abscisic acid mitochondria pentatricopeptide repeat protein RNA editing drought tolerance germination

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减小失真的新技术

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电声技术 1986年第6期 26-32页

作者： d.R.frey 唐治平

目前大多数放大器都以低失真为设计基础。已经提出的前馈和反馈线路能进一步改善电路性能,但它们各有优缺点。本文提出了一种通过调节反馈放大器回路增益改进电路性能的方法。从理论上进行了论述,并给出了验证该理论的试验结果。

关键词：反馈放大器前馈电路正向增益

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THEMIS observations of two substorms on February 26,2008

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Science China(Technological Sciences) 2010年第5期53卷 1328-1337页

作者： CHU XiangNing PU ZuYin CAO Xin WANG Jue V.MISHIN V.ANGELOPOULOS LIU Jiang WEI Yong K.H.GLASSMEIER J.MCFAddEN d.LARSON S.MENdE H.frey C.T.RUSSELL I.MANN d.SIBECK ZONG QiuGang FU SuiYan XIE Lun T.I.SAIFUdINOVA M.V.TOLOCHKO L.A.SAPRONOVA H.REME E.LUCEK School of Earth and Space Sciences Peking UriiversityBeijing 100871China Institute of Solar-Terrestrial Physics Russian Academy of Sciences IGPP UCLA Instiute of Geophysics and Extraterrestrial Physics Technical University of BraunschweigBraunschweig and Max Planck Institute of Solar System Research Space Sciences Laboratory University of California department of Physics University of Alberta Code 674 NASA/GSFC Centre d'Etude Spatiale des Rayonnements Blackett Laboratory Imperial College London

Two substorms occurred at ～04:05 and ～04:55 UT on February 26,2008 are studied with the in-situ observations of THEMIS satellites and ground-based aurora and magnetic field *** et *** made a comprehensive study of the 04:55 UT *** showed detailed features of the two substorms with much attention to the first event and to the rela-tionship between mid-tail magnetic reconnection(MR) and substorm *** was found that in the earlier stage of each substorm,a first auroral intensification occurred 2-3 min soon after the start of mid-tail MR,followed by a slow and very lim-ited *** auroral arcs were weak,short-lived,and localized,characterizing all features of a *** re-garded the first auroral brightening as the initial onset of the substorms.A few minutes later,a second stronger auroral intensification appeared,followed by quick and extensive *** was interesting to note that the second brightening and related poleward expansion happened almost simultaneously(within a couple of minutes) with the onset of earthward flow and dipolarization in the near-Earth tail and other phenomenon of the substorm expansion *** thus regarded the second auroral brightening as the major onset of the ***,it was seen that during the growth phase of the two substorms,the polar cap open flux Ψ kept increasing,while it quickly reduced during the substorm expansion and recovery *** variations of Ψ implied that the evolution of the two substorm expansion phases were closely related to MR of tail lobe open field *** of substorm activities revealed that the two events studied were small substorms;while estimate of MR rate indicated that the MR processes in the two substorms were *** aforementioned observations suggested that mid-tail MR initiated the pseudobreakup first;the earthward flow generated by MR transported magnetic flux and energy to the near-Earth tail to cause the formatio

关键词： substorm auroral intensification/brightening auroral expansion dipolarization magnetic reconnection

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