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Genetic diversity and differentiation follow secondary succession in a multi-species study on woody plants from subtropical China

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Journal of Plant Ecology 2017年第1期10卷 213-221页

作者： christoph z.hahn Stefan G.Michalski Markus Fischer Walter Durka Department of Community Ecology(BzF) Helmholtz Centre for Environmental Research—UFZTheodor-Lieser-Straße 4D-06120 HalleGermany Institute of Plant Sciences University of BernAltenbergrain 21CH-3013 BernSwitzerland German Centre for Integrative Biodiversity Research(iDiv)Halle-Jena-Leipzig Deutscher Pl.5E04103 LeipzigGermany

Aims Species diversity and genetic diversity may be affected in parallel by similar environmental ***,genetic diversity may also be affected independently by habitat *** aim at disentangling relationships between genetic diversity,species diversity and habitat characteristics of woody species in subtropical *** We studied 11 dominant tree and shrub species in 27 plots in Gutianshan,China,and assessed their genetic diversity(A_(r))and population differentiation(F′_(ST))with microsatellite *** tested if Ar and population specific F′_(ST) were correlated to local species diversity and plot ***-model inference and model averaging were used to determine the relative importance of each ***,we tested for isolation-by-distance(IBD)and isolation-by-elevation by regressing pairwise F′_(ST) against pairwise spatial and elevational *** Findings Genetic diversity was not related to species diversity for any of the study ***,our results do not support joint effects of habitat characteristics on these two levels of ***,genetic diversity in two understory shrubs,Rhododendron simsii and Vaccinium carlesii,was affected by plot age with decreasing genetic diversity in successionally older *** differentiation increased with plot age in *** and Lithocarpus *** shows that succession can reduce genetic diversity within,and increase genetic diversity between ***,we found four cases of IBD and two cases of *** former indicates inefficient pollen and seed dispersal by animals whereas the latter might be due to phenological *** patterns indicate that succession can affect genetic diversity without parallel effects on species diversity and that gene flow in a continuous subtropical forest can be restricted even at a local scale.

关键词： Allelic richness population differentiation habitat characteristics gene flow species-genetic diversity correlation SGDC

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Opposing intraspecific *** diversity effects on herbivory and growth in subtropical experimental tree assemblages

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Journal of Plant Ecology 2017年第1期10卷 242-251页

作者： christoph z.hahn Pascal A.Niklaus Helge Bruelheide Stefan G.Michalski Miaomiao Shi Xuefei Yang Xueqin zeng Markus Fischer Walter Durka Helmholtz Centre for Environmental Research—UFz Department of Community Ecology(BZF)Theodor-Lieser-Straße 4D-06120 HalleGermany Department of Evolutionary Biology and Environmental Studies University of ZürichWinterthurerstrasse 190CH-8057 ZürichSwitzerland Institute of Biology Martin Luther University Halle-WittenbergAm Kirchtor 106108 HalleGermany German Centre for Integrative Biodiversity Research(iDiv)Halle-Jena-Leipzig Deutscher Platz 5e04103 LeipzigGermany South China Botanical Garden 723 Xingke RoadGuangzhou 510650China Key Laboratory of Biodiversity and Biogeography Kunming Institute of BotanyChinese Academy of Sciences132 Lanhei RoadKunming 650204China Kadoorie Farm and Botanic Garden Lam Kam RoadTai PoNew TerritoriesHong Kong Institute of Plant Sciences University of BernAltenbergrain 21CH-3013 BernSwitzerland

Aims Positive plant diversity-ecosystem function relations are ultimately driven by variation in functional traits among individuals that form a *** date,research has largely focused on the role of species diversity for ecosystem ***,substantial intraspecific trait variation is common and a significant part of this variation caused by genetic differences among ***,we studied the relative importance of species diversity and seed family(SF)diversity within species for growth and herbivory in experimental subtropical tree *** In 2010,we set up a field experiment in subtropical China,using four species from the local species *** were raised from seeds,with seeds from the same mother tree forming an *** established 23 plots containing one or four species(species diversity treatment)and one or four SFs per species(SF diversity treatment).Tree growth(stem diameter,plant height and crown expansion)and herbivory(percentage leaf loss due to leaf chewers)were monitored annually from 2011 to *** findings Tree species richness promoted growth but had no effect on *** contrast,SF diversity reduced growth and increased herbivory but only so in species *** of the observed effects were time dependent,with the largest effect found in *** results suggest that biodiversity can affect plant performance directly via tree species-species interactions,or context dependent,via potential effects on inter-trophic *** important conclusions should be drawn from our ***,in future studies regarding biodiversity and ecosystem functioning(BEF)relationships,intraspecific genetic diversity should be given similar weight as species diversity as it has often been neglected and its effects are not well ***,we demonstrate opposite effects of biodiversity among and within species,stressing the importance to consider the effects of multiple levels of biodiversity simul

关键词： BEF-China species diversity genetic diversity growth herbivory

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Optical probing of ultrafast laser-induced solid-to-overdense-plasma transitions

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Light(Science & Applications) 2024年第5期13卷 973-984页

作者： Yasmina Azamoum Georg Alexander Becker Sebastian Keppler Guillaume Duchateau Stefan Skupin Mickael Grech Fabrice Catoire Sebastian Hell Issa Tamer Marco Hornung Marco Hellwing Alexander Kessler Franck Schorcht Malte christoph Kaluza GSI Helmholtzzentrum für Schwerionenforschung Planckstr.164291 DarmstadtGermany. Helmholtz Institute Jena Fröbelstieg 307743 JenaGermany. Institute of Optics and Quantum Electronics Friedrich-SchillerUniversität JenaMax-Wien-Platz 107743 JenaGermany. CEA-CESTA 15 Avenue des SablièresCS6000133116 Le BarpCedexFrance Institut Lumière Matière UMR 5306-CNRSUniversitéde Lyon 169622 VilleurbanneFrance. LULI CNRSCEASorbonne UniversitéInstitut Polytechnique de ParisPalaiseauFrance. Universitéde Bordeaux-CNRS-CEA CELIAUMR 5107 TalenceFrance

Understanding the solid target dynamics resulting from the interaction with an ultrashort laser pulse is a challenging fundamental multi-physics problem involving atomic and solid-state physics,plasma physics,and laser *** of the initial interplay of the underlying processes is essential to many applications ranging from lowpower laser regimes like laser-induced ablation to high-power laser regimes like laser-driven ion *** the properties of the so-called pre-plasma formed as the laser pulse’s rising edge ionizes the target is complicated from the theoretical and experimental point of view,and many aspects of this laser-induced transition from solid to overdense plasma over picosecond timescales are still open *** the one hand,laser-driven ion acceleration requires precise control of the pre-plasma because the efficiency of the acceleration process crucially depends on the target properties at the arrival of the relativistic intensity peak of the *** the other hand,efficient laser ablation requires,for example,preventing the so-called“plasma shielding”.By capturing the dynamics of the initial stage of the interaction,we report on a detailed visualization of the pre-plasma formation and ***-thin diamond-like carbon foils are shown to transition from solid to plasma during the laser rising edge with intensitieszation,collisions,and expansion.

关键词： laser acceleration solid

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Improvement of quantitative testing of liver function in patients with chronic hepatitis C after installment of antiviral therapy

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World Journal of Gastroenterology 2005年第35期11卷 5521-5524页

作者： Matthias Ocker Marion Ganslmayer Steffen zopf Susanne Gahr christopher Janson Eckhart G. hahn christoph Herold Department of Medicine I University Erlangen-Nuernberg Ulmenweg 18 Erlangen 91054 Germany

MM： To investigate if and to what extent antiviral therapy influenced a broad panel of quantitative testing of liver function （QTLF）. METHODS： Fifty patients with chronic hepatitis C were either treated with interferon （n = 8）, interferon/ribavirin （n = 19） or peg-interferon/ribavirin （n = 23）. Quantitative testing of liver function, including aminopyrine breath test （ABT）, galactose elimination capacity （GEC）, sorbitol clearance （SCI） and indocyanine green clearance （ICG） was performed before and 3 mo after initiation of antiviral therapy. RESULTS： After 3 mo of antiviral treatment, 36 patients showed normal transaminases and were negative for HCVRNA, 14 patients did not respond to therapy. ABT and GEC as parameters of microsomal and cytosolic liver function were reduced in all patients before therapy initiation and returned to normal values in the 36 therapy responders after 3 too. Parameters of liver perfusion （SCl and ICG） were not affected by antiviral therapy. In the 14 non-responders, no changes in QTLF values were observed during the treatment period. CONCLUSION： ICG and SCI remained unaffected in patients with chronic hepatitis C, while ABT and GEC were significantly compromised. ABT and GEC normalized in responders to antiviral therapy. Early determination of ABT and GEC may differentiate responders from non-responders to antiviral treatment in hepatitis C.

关键词： Aminopyrine breath test Galactose eliminationcapacity Indocyanine green clearance Sorbitol clearance Hepatitis C Interferon Ribavirin

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Sclerosing cholangitis following severe trauma: Description of a remarkable disease entity with emphasis on possible pathophysiologic mechanisms

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World Journal of Gastroenterology 2005年第27期11卷 4199-4205页

作者： Johannes Benninger Rainer Grobholz Yurdaguel Oeztuerk christoph H.Antoni Eckhart G.hahn Manfred V.Singer Richard Strauss Department of Medicine Ⅰ Department of Pathology Department of Medicine II Department of Medicine Ⅱ

MM： Persistent cholestasis is a rare complication of severe trauma or infections. Little is known about the possible pathomechanisms and the clinical ***： Secondary sclerosing cholangitis was diagnosed in five patients with persistent jaundice after severe trauma （one burn injury, three accidents, one power current injury）. Medical charts were retrospectively reviewed with regard to possible trigger mechanisms for cholestasis, and the clinical course was ***： Diagnosis of secondary sclerosing cholangitis was based in all patients on the primary sclerosing cholangitis （PSC）-Iike destruction of the intrahepatic bile ducts at cholangiography after exclusion of PSC. In four patients, arterial hypotension with subsequent ischemia may have caused the bile duct damage, whereas in the case of power current injury direct thermal damage was assumed to be the trigger mechanism. The course of secondary liver fibrosis was rapidly progressive and proceeded to liver cirrhosis in all four patients with a follow-up 〉2 years. Therapeutic possibilities were ***： Posttraumatic sderosing cholangitis is a rare but rapidly progressive disease, probably caused by ischemia of the intrahepatic bile ducts via the peribiliary capillary plexus due to arterial *** should be aware of this disease in patients with persistent cholestasis after severe trauma.

关键词： Life-threatening trauma Arterial hypotension Cholestasis Ischemia of intrahepatic bile ducts Secondary sclerosing cholangitis Posttraumatic sclerosing cholangitis

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The evolutionary ecology of symbiont-conferred resistance to parasitoids in aphids

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Insect Science 2014年第3期21卷 251-264页

作者： christoph Vorburger Institute of Integrative Biology ETH Zǖrich Universitātstrasse 16 8092 Zǖdch EAWAG Swiss Federal Institute of Aquatic Science and Technology Uberlandstrasse 133 8600 Dǖbendoàf Switzerland

Aphids may harbor a wide variety of facultative bacterial endosymbionts. These symbionts are transmitted maternally with high fidelity and they show horizontal trans-mission as well, albeit at rates too low to enable infectious spread. Such symbionts need to provide a net fitness benefit to their hosts to persist and spread. Several symbionts haveachieved this by evolving the ability to protect their hosts against parasitoids. Reviewing empirical work and some models, I explore the evolutionary ecology of symbiont-conferredresistance to parasitoids in order to understand how defensive symbiont frequencies are maintained at the intermediate levels observed in aphid populations. I further show thatdefensive symbionts alter the reciprocal selection between aphids and parasitoids by augmenting the heritable variation for resistance, by increasing the genetic specificity of thehost-parasitoid interaction, and by inducing environment-dependent trade-offs. These effects are conducive to very dynamic, symbiont-mediated coevolution that is driven by frequency-dependent selection. Finally I argue that defensive symbionts represent a problem for biological control of pest aphids, and I propose to mitigate this problem byexploiting the parasitoids＇ demonstrated ability to rapidly evolve counteradaptations to symbiont-conferred resistance.

关键词： aphids biological control coevolution genotype × genotype interaction Hamiltonella defensa parasitoid resistance symbiosis

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Assessment of metastatic liver disease in patients with primary extrahepatic tumors by contrast-enhanced sonography versus CT and MRI

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World Journal of Gastroenterology 2006年第11期12卷 1699-1705页

作者： christoph F Dietrich Wolfgang Kratzer Deike Strobel Etienne Danse Robert Fessl Alfred Bunk Udo Vossas Karlheinz Hauenstein Wilhelm Koch Wolfgang Blank Matthijs Oudkerk Dietbert hahn Christian Greis Department of Internal Medicine Ⅱ Johann Wolfgang Goethe University Hospital 60590 FrankfurtGermany Department of Internal Medicine Ⅰ University Hospital Ulm 89070Germany Medical Clinic Ⅰ University Hospital Erlangen 91054Germany Department of Radiology University Hospital St.Luc Brussels 1200Belgium Department of Radiology Central Hospital Augsburg 86156Germany Department for Visceral Thoracic and Vascular Surgery University HospitalDresden 01307Germany Department of Radiology Marien Hospital DUsseldorf 40479Germany Department of Radiology University Hospital Rostock 18055Germany Medical Clinic Ⅱ Leopoldina Hospital Schweinfurt 97422Germany Department of Internal Medicine Hospital am Steinenberg Reutlingen 72764Germany Department of Radiology University Hospital Groningen 9700Netherlands Department of Radiology University Hospital Würzburg 97080Germany Clinical Research Bracco Altana Pharma Konstanz 78467Germany

AIM： To evaluate contrast-enhanced ultrasonography （CEUS） using SonoVue in the detection of liver metastases in patients with known extrahepatic primary tumors versus the combined gold standard comprising CT, MRI and clinical/histological data. METHODS： It is an international multicenter study, and there were 12 centres and 125 patients （64 males, 61 females, aged 59 ± 11 years） involved, with 102 patients per protocol. Primary tumors were colorectal in 35%, breast in 27%, pancreatic in 17% and others in 21%. CEUS using SonoVue was employed with a Iow-mechanical-index technique and contrast-specific software using Siemens Elegra, Philips HDI 5000 and Acuson Sequoia; continuous scanning for at least five minutes. RESULTS： CEUS with SonoVue increased significantly the number of focal liver lesions detected versus unenhanced sonography. In 31.4% of the patients, more lesions were found after contrast enhancement. The total numbers of lesions detected were comparable with CEUS （55）, triple-phase spiral CT （61） and HRI with a liverspecific contrast agent （53）. Accuracy of detection of metastatic disease （i.e. at least one metastatic lesion） was significantly higher for CEUS （91.2%） than for unenhanced sonography （81.4%） and was similar to that of triple-phase spiral CT （89.2 %）. In 53 patients whose CEUS examination was negative, a follow-up examination 3-6 months later confirmed the absence of metastatic lesions in 50 patients （94.4%）. CONCLUSION： CEUS is proved to be reliable in the detection of liver metastases in patients with known extrahepatic primary tumors and suspected liver lesions.

关键词： CT MRI Metastasis Detection SonoVue

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ANALYSIS OF MULTI-INDEX MONTE CARLO ESTIMATORS FOR A zAKAI SPDE

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Journal of Computational Mathematics 2018年第2期36卷 202-236页

作者： christoph Reisinger zhenru Wang Mathematical Institute University of Oxford Woodstock Road Oxford OX2 6GG UK

In this article, we propose a space-time Multi-Index Monte Carlo （MIMC） estimator for a one-dimensional parabolic stochastic partial differential equation （SPDE） of zakai type. We compare the complexity with the Multilevel Monte Carlo （MLMC） method of Giles and Reisinger （2012）, and find, by means of Fourier analysis, that the MIMC method：（i） has suboptimal complexity of 0（ε^-21 ｜ogε｜） for a root mean square error （RMSE） z if the same spatial discretisation as in the MLMC method is used; （ii） has a better complexity of 0（ε^-21 ｜ogε｜） if a carefully adapted discretisation is used; （iii） has to be adapted for non-smooth functionals. Numerical tests confirm these findings empirically.

关键词： Parabolic stochastic partial differential equations Multilevel Monte Carlo,Multi-index Monte Carlo Stochastic finite differences zakai equation.

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SolarGAN:Synthetic annual solar irradiance time series on urban building facades via Deep Generative

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能源与人工智能(英文) 2023年第2期12卷 1-21页

作者： Yufei zhang Arno Schlueter christoph Waibel Chair of Architecture and Building Systems(A/S) ETH ZurichStefano-Franscini-Platz 18093 ZurichSwitzerland

Building Integrated Photovoltaics (BIPV) is a promising technology to decarbonize urban energy systems viaharnessing solar energy available on building envelopes. While methods to assess solar irradiation, especiallyon rooftops, are well established, the assessment on building facades usually involves a higher effort due tomore complex urban features and obstructions. The drawback of existing physics-based simulation programsare that they require significant manual modeling effort and computing time for generating time resolveddeterministic results. Yet, solar irradiation is highly intermittent and representing its inherent uncertainty maybe required for designing robust BIPV energy systems. Targeting on these drawbacks, this paper proposes adata-driven model based on Deep Generative Networks (DGN) to efficiently generate stochastic ensembles ofannual hourly solar irradiance time series on building facades with uncompromised spatiotemporal resolutionat the urban scale. The only input required are easily obtainable fisheye images as categorical shading maskscaptured from 3D models. In principle, even actual photographs of urban contexts can be utilized, given they are semantically segmented. The potential of our approach is that it may be applied as a surrogate for timeconsuming simulations, when facing lacking information (e.g., no 3D model exists), and to use the generatedstochastic time-series ensembles in robust energy systems planning. Our validations exemplify a good fidelityof the generated time series when compared to the physics-based simulator. Due to the nature of the usedDGNs, it remains an open challenge to precisely reconstruct the ground truth one-to-one for each hour of theyear. However, we consider the benefits of the approach to outweigh the shortcomings. To demonstrate themodel’s relevance for urban energy planning, we showcase its potential for generative design by parametricallyaltering characteristic features of the urban environment and produc

关键词： Urban solar potential Data-driven Deep Generative Networks(DGN) Building-integrated photovoltaic(BIPV) Generative Adversarial Network(GAN) Variational Autoencoder(VAE)

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Photoinduced E to z isomerization of tetraphenylethylene derivatives within organometallic supramolecular assemblies

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Science China Chemistry 2021年第10期64卷 1709-1715页

作者： Xiao-Xu Liu Yang Li Xin Li F.Ekkehardt hahn Ying-Feng Han College of Chemistry and Materials Science Northwest UniversityXi'an 710127China Institut fiir Anorganicshe und Analytische Chemie Westfalische Wilhelms-Universitat Munster Corrensstrasse 30 48149 MunsterGermany

Isolation of E-1,2-bis(4-bromophenyl)-1,2-diphenyl-ethylene from the E/z isomer mixture obtained by a Mc Murry coupling reaction and reaction of this isomer with imidazole followed by N-alkylation with n Bu Br and anion exchange yielded the bisimidazolium tetraphenylethylene(TPE)derivative H_(2)-E-1(PF_(6))_(2).The reaction of H_(2)-E-1(PF_(6))_(2) with Ag_(2)O yielded the dinuclear metallarectangle[Ag_(2)(E-1)2](PF_(6))_(2) where the two bis-NHC donors E-1 bridge two silver *** of[Ag_(2)(E-1)2](PF_(6))_(2) leads to E/z isomerization of the di-NHC ligand and formation of z-1 in the mononuclear complex[Ag(z-1)]PF_(6).Demetallation of the di-NHC ligand with NH_(4)Cl/NH_(4)PF_(6) yielded bisimidazolium salt H_(2)-z-1(PF_(6))_(2).The unique isomerization of the E-TPE derivative into its z-isomer via metal complex formation/irradiation/demetallation cannot be achieved by irradiation of the individual imidazolium *** emissive properties of the TPE complexes[Ag_(2)(E-1)2](PF_(6))_(2) and[Ag(z-1)]PF_(6) have been investigated.

关键词： N-heterocyclic carbene tetraphenylethylene photochemical isomerization fluorescence EzI process

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