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Stand dynamics of the drought-affected floodplain forests of Araguaia River,Brazilian Amazon

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Forest Ecosystems 2017年第3期4卷 201-210页

作者： Jürgen Homeier Dariusz Kurzatkowski christoph Leuschner Plant Ecology Albrecht von Haller Institute for Plant Sciences University of Goettingen

Background： The floodplain forests of Araguaia River, a clear-water river in the southeastern Amazon（Tocantins State, Brazil）, are characterized by seasonal flooding up to 3.5 m height, low nutrient levels in the water, and seasonal drought periods of 4–5 ***： We studied the forest dynamics（tree diameter growth, tree mortality and recruitment） of this unique forest ecosystem over a 5-year period by repeated censuses in 12 permanent plots established along a flooding ***： The cumulative basal area in the plots increased by 0.84（±0.45） m^2·ha^-1·yr^-1（mean ±SD） in the annual y-flooded（AF） plots in lower terrain and by 0.69（±1.00） m^2·ha^-1·yr^-1 in the higher non-annual y flooded（NAF） plots, corresponding to an aboveground biomass increase of 0.81（±0.57） and 0.69（±1.58） Mg·ha^-1·yr^-1 in the AF and NAF plots, indicating a recent carbon sink in the biomass. Mean diameter growth rate was 1.8（±0.44） mm·yr^-1 in the AF and 2.0（±0.56） mm·yr^-1 in the NAF plots（corresponding to a coarse wood production of 1.53（±1.29） and 2.02（±0.52） Mg·ha^-1·yr^-1）,indicating no flooding effect on radial growth. Mean mortality rates in the 5-year period were 1.9（±0.37）·yr^-1 in the AF plots and 1.8（±0.87）%·yr^-1 in the NAF plots with no differences along the flooding gradient. Highest mortalities were registered in the AF plots for the 10–20 cm dbh class（2.4%·yr^-1）, likely as a consequence of flooding,and in the NAF plots for the 40–50 cm dbh class（3.0%·yr^-1）, probably mainly caused by ENSO-related ***： We conclude that these drought-affected tropical floodplain forests have a lower standing biomass and aboveground productivity than central Amazonian floodplain forests in more humid climates, and the imprint of the flooding gradient on stand dynamics is relatively weak, which may result from the lower flooding height and the interaction of flooding with low nutrient supply and periodic drought.

关键词： Amazon Diameter growth Dry season Flooding regime Mortality rate Productivity Tree recruitment

CityGML goes mobile: application of large 3D CityGML models on smartphones

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International Journal of Digital Earth 2019年第1期12卷 25-42页

作者： christoph Blut Timothy Blut Jörg Blankenbach Department of Computing in Civil Engineering and Geo Information Systems Geodetic InstituteRWTH Aachen UniversityAachenGermany

CityGML,a semantic information model for digital/virtual city models has become quite popular in various *** the data format is still actively under development,it is already supported by different software solutions,especially GIS-based desktop *** systems on the other hand are still neglected,even though the georeferenced objects of CityGML have many application fields,for example,in the currently popular area of location-based Augmented *** this paper we present an independent multi-platform CityGML viewer,its architecture and specific implementation techniques that we use to realize and optimize the process of visualizing CityGML data for use in Augmented *** main focus lies in improving the implementation on mobile devices,such as smartphones,and assessing its usability and performance in comparison to web-based *** to the constrained hardware resources of smartphones,it is a particular challenge to handle complex 3D objects and large virtual worlds as provided by CityGML,not only in terms of memory and storage space,but also with respect to mobile processing units and display sizes.

关键词： CityGML city model android 3D visualization real-time rendering

Time Lag Effect of Supply Chain Management on Firm Performance

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Journal of Systems Science and Systems Engineering 2021年第3期30卷 321-338页

作者： Lu Xiao Quan Zhu Xiaolin Xu christoph Wäger School of Business Nanjing UniversityNanjing210000China Faculty of International Business&Communication Zuyd University of Applied SciencesMaastrichtP.O.Box 634NL-6200 APthe Netherlands University of Göttingen Göttingen37083Germany

The objective of this paper is to identify time lag effect in the relationship between supply chain management and financial *** hypothesize that firms with higher supply chain management capability are associated with higher financial performance and the impact would last *** addition,we introduce two contextual variables,ownership and market orientation,to detect the moderating effect of ownership structure and organizational culture,*** use firm-level empirical data from 1,131 public Chinese manufacturing firms for the 2010–2019 period to investigate the effect and the result shows that there is a two-year time lag effect in the relationship,which means the positive impact of current supply chain management would last for three ***,we find evidence that supply chain management in non-state-owned firms is more efficient and its positive financial impact would last longer than that in state-owned ***,we indicate that market-orientation can’t moderate the relationship between supply chain management and financial performance.

关键词： Supply chain management financial performance time lag effect ownership market orientation

Viscoelasticity and shear resistance at the aggregate scale of structured and organic carbon-free Chernozems

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Pedosphere 2023年第5期33卷 754-764页

作者： christoph HAAS Rainer HORN Philipp SAGGAU Rainer DUTTMANN Institute for Plant Nutrition and Soil Science University of KielKiel 24118Germany Department of Geography Division of Landscape Ecology and Geoinformation SciencesUniversity of KielKiel 24118Germany

Soil rheology characterises the flow behaviour of soils at the particle-particle to aggregate *** sweep tests(ASTs)are often the method of choice for parameterizing soil flow properties,such as the shear strain values at the end of the linear viscoelastic range(i.e.,the deformation is mainly elastic)and at the yield point(i.e.,elastic equals plastic deformation).Samples from seven soil profiles and five soil depths of Chernozems,collected in the Maidanetske study area,close to Uman City of Ukraine,were analysed to evaluate the effect of soil organic carbon(SOC)on the parameters related to soil microstructural stability derived from *** organic carbon was removed with H_(2)O_(2)to determine the soil texture-dependent values of soil rheological properties,which were compared to the values determined for samples with intact water-stable *** shear resistance-related parameters increased for aggregated soil samples compared to SOC-free soil samples,indicating an increase in soil stability due to *** contrast,the values of the overall viscoelasticity and the shear strain were reduced for aggregated soil samples,indicating decreased soil *** functions were applied to predict the shear strain-dependent loss and storage moduli and shear stress values as a function of SOC *** particles(630–2000μm)and volumetric water content improved the *** conclude that increased SOC content,through the gluing and cementing effects of SOC and altered aggregate shapes compared to SOC-free soil materials,contributes to higher microstructural ***,the increased water content in the SOC-containing soil samples reversed soil strengthening *** was due to the fact that a more rapid increase in positive water pressure under shear stress weakened the samples and the spherical aggregates began to rotate more easily,thus loosing energy,when compared to platy particles of the SOC-free soil materials.

关键词： aggregation rheology shear strain shear stress soil organic carbon depletion soil stability

Soil carbon and nutrient stocks under Scots pine plantations in comparison to European beech forests: a paired-plot study across forests with different management history and precipitation regimes

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Forest Ecosystems 2021年第3期8卷 628-643页

作者： Marco Diers Robert Weigel Heike Culmsee christoph Leuschner Plant Ecology Albrecht-von-Haller-Institute for Plant SciencesUniversity of GoettingenUntere Karspuele 237073 GoettingenGermany Centre of Biodiversity and Sustainable Land Use(CBL) University of GoettingenBuesgenweg 137077 GoettingenGermany

Background:Organic carbon stored in forest soils(SOC)represents an important element of the global C *** is thought that the C storage capacity of the stable pool can be enhanced by increasing forest productivity,but empirical evidence in support of this assumption from forests differing in tree species and productivity,while stocking on similar substrate,is ***:We determined the stocks of SOC and macro-nutrients(nitrogen,phosphorus,calcium,potassium and magnesium)in nine paired European beech/Scots pine stands on similar Pleistocene sandy substrates across a precipitation gradient(560–820mm∙yr−1)in northern Germany and explored the influence of tree species,forest history,climate,and soil pH on SOC and nutrient ***:While the organic layer stored on average about 80%more C under pine than beech,the pools of SOC and total N in the total profile(organic layer plus mineral soil measured to 60 cm and extrapolated to 100 cm)were greater under pine by about 40%and 20%,*** contrasts with a higher annual production of foliar litter and a much higher fine root biomass in beech stands,indicating that soil C sequestration is unrelated to the production of leaf litter and fine roots in these stands on Pleistocene sandy *** pools of available P and basic cations tended to be higher under *** precipitation nor temperature influenced the SOC pool,whereas tree species was a key *** extended data set(which included additional pine stands established more recently on former agricultural soil)revealed that,besides tree species identity,forest continuity is an important factor determining the SOC and nutrient pools of these ***:We conclude that tree species identity can exert a considerable influence on the stocks of SOC and macronutrients,which may be unrelated to productivity but closely linked to species-specific forest management histories,thus masking weaker climate and soil chemistry effects on pool sizes

关键词： Basic cations Fagus sylvatica Forest history Nitrogen Paired plots Pinus sylvestris Productivity effect Soil organic carbon Tree species effect

Enhancement of methane yield from cotton stalks by mechanical pre-treatment

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Carbon Resources Conversion 2021年第1期4卷 164-168页

作者： Rafat Al Afif christoph Pfeifer Institute of Chemical and Energy Engineering University of Natural Resources and Life SciencesViennaMuthgasse 107Vienna 1190Austria

Cotton stalks(CS)are lignocellulosic agricultural by-products,a potential source for biogas production,but pretreatment must be considered since hydrolysis is the rate-limiting stage for lignocellulosic biomass *** study investigates the feasibility of mechanical pretreatment of CS to enhance methane *** anaerobic digestion of CS samples with particle sizes ranging from 0.5 to 65 mm was carried out in 1 L eudiometer batch digesters for 48 days at 37◦*** showed that methane yield was inversely proportional to particle size,and the quality of biogas was good(54.0-55.2%CH_(4)).Significant increases in methane yield were observed with 20.3%and 26%for samples with a particle size of 3 mm and 0.5 mm,respectively,compared to untreated *** coefficient of anaerobic energy turnover was relatively low(20.2-25.5%).Reduction of the CS particle size to 3 mm or less is recommended to achieve effective methane conversion and decrease the retention time in an anaerobic digester from 31 to about 25 ***,to offset the high energy demand required for grinding,further research should be conducted in combining size reduction with chemical and physicochemical pretreatment.

关键词： Cotton stalks Anaerobic digestion Methane yield Mechanical pretreatment

Ultrasound findings in autoimmune hepatitis

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World Journal of Gastroenterology 2018年第15期24卷 1583-1590页

作者： Yi Dong Andrej Potthoff christoph Klinger Ana Paula Barreiros Dariusz Pietrawski christoph F Dietrich Department of Ultrasound Zhongshan Hospital Fudan University Department of Gastroenterology Hepatology and Endocrinology Medizinische Hochschule Hannover Department of Internal Medicine 1 Klinikum Ludwigsburg German Organ Transplantation Foundation Region Mitte Department of Internal Medicine 2 Caritas-Krankenhaus Bad Mergentheim

Ultrasound findings in autoimmune hepatitis(AIH) have not been reported systematically so far. The use of reliable and accurate noninvasive methods for determining fibrosis stage is important in evaluation of treatment efficacy and fibrosis regression in AIH. Imaging plays an important role in detection of complications and ruling out other possible causes of chronic liver diseases. Ultrasound elastography cutoff values in AIH patients are not the same as those in patients with chronic viral hepatitis or non-alcoholic fatty liver disease. AIH is characterized by wide fluctuations in inflammatory activity. Here we report on current knowledge of ultrasound findings in AIH.

关键词： Autoimmune hepatitis Fibrosis stage Ultrasound Elastography Chronic liver diseases

DNA methylation profile of a hepatosplenic gamma/delta T-cell lymphoma patient associated with response to interferon-α therapy

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Cellular & Molecular Immunology 2021年第5期18卷 1332-1335页

作者： Jaydeep Bhat Anke KBergmann Silvio Waschina christoph Nerl christoph Kaleta Reiner Siebert Ole Ammerpohl Dieter Kabelitz Institute of Immunology Christian-Albrechts-University Kiel&University Hospital Schleswig-HolsteinCampus KielKielGermany Metabolic Programming School of Life Sciences WeihenstephanTechnical University Munich(TUM)85354FreisingGermany Institute of Human Genetics Christian-Albrechts-University Kiel&University Hospital Schleswig-HolsteinCampus KielKielGermany Institute of Human Genetics Medical School HannoverHannoverGermany Institute of Experimental Medicine Christian-Albrechts-University Kiel&University Hospital Schleswig-HolsteinCampus KielKielGermany Institute of Human Nutrition and Food Science Christian-Albrechts-University KielKielGermany Städtisches Krankenhaus München-Schwabing MunichGermany Institute of Human Genetics Ulm University&Ulm University Medical Center89081UlmGermany

The 2–5%γδT cells in healthy human peripheral blood recognize nonpeptide antigens,in contrast toαβT cells.1 DistinctγδT-cell malignancies have been identified,with hepatosplenic T-cell lymphoma(γδ-HSTL)being a rare but aggressive(median survival 13 months)subset.2γδ-HSTL usually presents with hepatosplenomegaly without lymphadenopathy,anemia,and *** is histologically characterized by the involvement of the hepatic sinusoids,splenic red pulp and bone marrow interstitium,with or without leukemic presentation in peripheral blood.3 A standard treatment regimen is not well established,but therapy mostly includes various chemotherapeutic ***,interferon-α(IFN-α)has been proven to be effective in some patients withγδ-HSTL,but other patients require allogeneic or autologous stem cell transplantation.

关键词： hepato splenic interferon

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)