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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

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

Androgen receptor expression in clinically localized prostate cancer： immunohistochemistry study and literature review

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Asian Journal of Andrology 2008年第6期10卷 855-863页

作者： Yi-Qing Qiu Ivo leuschner Peter Martin Braun Department of Urology the Second Affliated Hospital of Zhejiang University Hangzhou 310009 China Department of Urology and Pediatric Urology Department of Pathology Universitgitsklinikum Schleswig-Holstein Campus Kiel Kiel 24105 Germany

Aim： To evaluate androgen receptor （AR） expression in clinically localized prostate cancer （PCa）. Methods： Specimens were studied from 232 patients who underwent radical prostatectomy for clinically localized prostatic adenocarcinoma without neoadjuvant hormonal therapy or chemotherapy at our institution between November 2001 and June 2005. Immunohistochemical study was performed using an anti-human AR monoclonal antibody AR441. The mean AR density in the hot spots of different histological areas within the same sections were compared and the correlation of malignant epithelial AR density with clinicopathological parameters such as Gleason score, tumor, nodes and metastases （TNM） stage and pre-treatment prostate-specific antigen （PSA） value was assessed. Results： AR immunoreactivity was almost exclusively nuclear and was observed in tumor cells, non-neoplastic glandular epithelial cells and a proportion of peritumoral and interglandular stromal cells. Mean percentage of AR-positive epithelial cells was significantly higher in cancer tissues than that in normal prostate tissues （mean e SD, 90.0% ± 9.3% vs. 85.3% ±9.7%, P 〈 0.001）. The histological score yielded similar results. The percentage ofAR immunoreactive prostatic cancer nuclei and histological score were not correlated with existing parameters such as Gleason score, tumor, nodes and metastases stage and pre-treatment PSA value in this surgically treated cohort. Conclusion： The results of the present study suggest that there may be limited clinical use for determining AR expression （if evaluated in hot spots） in men with localized PCa.

关键词： androgen receptor prostate cancer immunohistochemistry

Regeneration of Nothofagus dombeyi(Mirb.)?*** little to moderately disturbed southern beech forests in the Andes of Patagonia(Argentina)

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Forest Ecosystems 2023年第4期10卷 472-482页

作者： Stefan Zerbe Stefanie T.Storz Georg Leitinger Natalia Zoe Joelson José Bava Steffi Heinrichs Christoph leuschner Gabriel Loguercio Alois Simon María F.Urretavizcaya Helge Walentowski Faculty of Agricultural Environmental and Food SciencesFree University of Bozen-Bolzano Department of Ecology University of Innsbruck Faculty of Resource Management HAWK University of Applied Sciences and Arts Department of Plant Ecology and Ecosystem Research Albrecht-von-Haller-Institute for Plant SciencesUniversity of G?ttingen Centro de Investigación y Extensión Forestal Andino Patagónico(CIEFAP) Department of Forest Planning Tyrol Forest Administration Office of the Tyrolean Government

Natural forests and stands subj ected to little to moderate human impact are continuously declining worldwide and with these,their biodiversity and ecosystem *** Nothofagus forests in the south of the South American continent are in a pristine state or only moderately impacted by *** grazing by livestock,in the past and still today often practiced in a non-sustainable way is,however,increasingly under discussion to meet current environmental and socio-economic ***,we investigate the regeneration of Nothofagus dombeyi,a keystone species of the Patagonian Andes,in secondary forests in Argentinian northern Patagonia,particularly addressing the role of disturbance through grazing by livestock at various *** test the hypothesis that the regeneration of this tree species is favored by grazing impact and,thus,disturbance of the herb layer and soil *** support of our hypothesis,Nothofagus dombeyi regeneration was significantly higher in terms of individuals and height classes in moderately grazed *** analysis shows significant positive effects of moderate grazing pressure,herb layer cover,and the occurrence of bare soil on the regeneration of Nothofagus *** results show that an integration of livestock grazing and forest regeneration is possible and that agroforestry systems can be an adequate management option for stakeholders in the region.A grazing management can also be part of a forest fire prevention ***,the regeneration success and grazing pressure should be continuously monitored.

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经导管主动脉瓣植入术研究进展

临床心血管病杂志 2016年第10期32卷 967-968页

作者：刘坤李裕舒 Emmanuel Chorianopoulos Florian leuschner 华中科技大学附属协和医院心内科华中科技大学同济医学院心血管病研究所武汉430022 Innere MedizinⅢ:kardiologie Angiologie und PneumologieMedizinische KlinikUniversitats Klinikum Heidelberg

随着人口结构的老龄化,主动脉瓣狭窄等心脏瓣膜病的发病率呈上升趋势。近年来,一种新的心血管介入治疗技术——经导管主动脉瓣植入术(TAVR)被临床试验证实其疗效,已被指南推荐治疗不能耐受外科手术或手术高危的严重主动脉瓣狭窄患者。... 详细信息

随着人口结构的老龄化,主动脉瓣狭窄等心脏瓣膜病的发病率呈上升趋势。近年来,一种新的心血管介入治疗技术——经导管主动脉瓣植入术(TAVR)被临床试验证实其疗效,已被指南推荐治疗不能耐受外科手术或手术高危的严重主动脉瓣狭窄患者。随着新一代经导管植入心脏瓣膜系统的开发和TAVR术临床实践的深入,TAVR手术并发症将得到有效的控制,其适应证不断拓宽,给心脏瓣膜病的治疗带来新的突破。

关键词：主动脉瓣狭窄导管植入

银基触头材料电弧侵蚀特性及裂纹形成机理分析(英文)

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中国电机工程学报 2004年第9期24卷 209-217页

作者：郭凤仪王国强董讷 leuschner F.W. 辽宁工程技术大学电气工程系辽宁阜新123000 比勒陀利亚大学电气电子与计算机工程系

利用数字显示时间继电器、交流接触器、断路器以及电阻性负载设计了一个简易的触头材料实验电路。用该实验电路对五种银基触头材料AgCdO(12),Ag(Sn,In)O,AgZnO(10),AgNi(10),AgC(5)根据不同的开断电流、开断次数、闭合压力和配对方式进... 详细信息

利用数字显示时间继电器、交流接触器、断路器以及电阻性负载设计了一个简易的触头材料实验电路。用该实验电路对五种银基触头材料AgCdO(12),Ag(Sn,In)O,AgZnO(10),AgNi(10),AgC(5)根据不同的开断电流、开断次数、闭合压力和配对方式进行了电弧侵蚀实验。根据实验结果得到了一些有实际意义的电弧侵蚀特性曲线。然后根据不同的开断电流及闭合压力对裂纹形貌进行了分析研究。最后,基于数学分析给出了用于判定出现滑移裂纹和热应力裂纹的理论判据。

关键词：电弧侵蚀特性裂纹形成机理银基触头材料

Na^+-k^+-ATPase activity of hepatocyte plasma membranes,reversible and irreversible alterations due to bile acids

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Chinese Medical Journal 1998年第1期111卷 93-93页

作者： T. You, S. Guldutuna, S. Bhatti and U. leuschner Gastroenterology Center of Internal Medical University Hospital D-60590 Frankfurt-Main Germany

Background Chenodeoxycholic acid (CDC) is an apolar bile salt and damages hepatocytes, whereas ursodeoxycholic acid (UDC) is a more polar bile salt and protects liver cell against toxic bile salts. We therefore investigated the activity of membrane associated Na + k + ATPase, a coenzyme of the sodium dependent bile salt carrier. Methods Liver plasma membranes (LPM) were isolated from rat livers according to the method of Song et al (J Cell Biol 1969; 41:124). The LPM were incubated with bile salts (TUDC, UDC, TCDC, CDC) in concentrations of 0.1 2 mmol/L for 0 30 minutes at room temperature. To study reversibility of the effect of CDC, LPM were diluted with buffer 50 times of volume after incubation. The activity of membrane associated Na + k+ ATPase was determined enzymatically at 37℃ and the phospholipid (PL) release into the supernatant was measured. Results CDC and TCDC both showed a dose dependent inhibition of the enzyme activity (Pkfurt Main, Germany (You T, Guldutuna S, Bhatti S and leuschner U)Initially TCDC induced an increase in enzyme activity at concentrations of 0.1 1 mmol/L, however, after 3 minutes activity repidly decreased to less than 30% of controls. Up to a concentration of 1 mmol/L CDC the inhibition of enzyme activity could be reversed by diluting the bile salt in the incubation medium. At a concentration of 2 mmol/L CDC activity was only partially restored and at this concentration a marked PL release into the supernatant was observed, indicating solubilization of the membranes. UDC did not decrease the enzyme activity at concentrations of 0.1 2 mmol/L. At a concentration of 2 mmol/L TUDC inhibited the Na + k + ATPase by about 20%. Solubilization of membrane PL was not observed. Conclusion CDC and TCDC inhibited Na + k + ATPase. Dilution of the bile salt with buffer reversed the inhibitory effect up to conc

关键词： ATPase activity of hepatocyte plasma membranes,reversible and irreversible alterations due to bile acids Na

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森林资源经营管理概论

森林资源经营管理概论

ASYMPTOTIC APPROXIMATION BY BERNSTEIN-DURRMEYER OPERATORS AND THEIR DERIVATIVES

1987年

作者：（美）鲁斯克纳（leuschner W.A.）蒋敏元译

书名原文:Introduction to forest resource management:本书包括三个主要部分。第一篇,论述了选择方案的评价以及计算决策指标的方法。第二篇集中讨论了森林采伐。第三篇,探讨了比较高级的经营管理方法。

关键词：森林经营学科:概论

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Analysis in Theory and Applications 2000年第2期16卷 1-12页

作者： Abel, Ulrich(Fachhochschule Giessen-FriedbergUniversity of Applied Sciences GermanyFachbereich MNDWilhelm - leuschner-Strasse 13D-61169 FriedbergE-mail:Ulrich.Abel@mnd.fh-friedberg.de) Fachhochschule Giessen-Friedberg University of Applied Sciences Germany

The concern of this paper is to study local approximation properties of the Bernstein-Durrmeyer operators Mn. We derive the complete asymptotic expansion of the operators Mn and their derivatives as n tends to infinity. It turns out that the appropriate representation is a series of reciprocal factorials. All coefficients are calculated explicitly in a very concise form. Our main theorem contains several earlier partial results as special cases. Finally, we obtain a Voronovskaja-type formula for simultaneous approximation by linear combinations of Mn,

关键词： oscillatory integral operator multiplier singularity