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Numerical Discrete-Domain Integral Formulations for Generalized Burger-Fisher Equation

Applied Mathematics 2020年第3期11卷 137-145页

作者： Okey Oseloka Onyejekwe Beruk Minale Fikru Habtamu tesfaye Amha Getenet Tamiru Bethelhem Mengistu Yohaness Demiss Nahom Alemseged Computational Science and Dynamics Systems Group Computational Science Program Addis Ababa University Arat-Kilo Campus Addis Ababa Ethiopia

In this study we use a boundary integral element-based numerical technique to solve the generalized Burger-Fisher equation. The essential feature of this method is the fundamental integral representation of the solution inside the problem domain by means of both the boundary and domain values. The occurrences of domain integrals within the problem arising from nonlinearity as well as the temporal derivative are not avoided or transferred to the boundary. However, unlike the classical boundary element approach, they are resolved within a finite-element-type discrete domain. The utility and correctness of this formulation are proved by comparing the results obtained herein with closed form solutions.

关键词： Burger-Fisher Equation Domain Integrals Boundary Element Finite-Element-Type Discrete Domain Boundary Integral Numerical Nonlinearity

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Phylogeny drives highly interconnected and nested mutualistic networks of woody plants and arbuscular mycorrhizal fungi in a Chinese subtropical forest

Phylogeny drives highly interconnected and nested mutualisti...

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中国菌物学会2015年学术年会

作者： Liang Chen Yong Zheng Cheng Gao Xiang-Cheng Mi Ke-Ping Ma tesfaye Wubet Liang-Dong Guo State Key Laboratory of Mycology Institute of MicrobiologyChinese Academy of Sciences University of Chinese Academy of Sciences State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of Sciences Department of Soil Ecology UFZ-Helmholtz Centre for Environmental Research The German Centre for Integrative Biodiversity Research(iDiv) University Leipzig

Unveiling the structure of mutualistic interaction networks has important implications for maintaining biodiversity and understanding ecosystem functioning, but the symbiotic interaction network structure of woody plants and arbuscular mycorrhizal fungi（AMF） in forest ecosystems remains poorly understood. We examined AMF communities from 166 root samples of 17 woody plant species from ten quadrats in a Chinese subtropical forest using 454 pyrosequencing of the 18 SrDNA. We tested the structure of the woody plant-AMF interaction network and the effects of phylogenetic constraints and environmental filtering on the network structure. Our results indicate that the woody plant-AMF network was highly connected and nested, but low modular or specialized. The nonrandom patterns in the woody plant-AMF network were affected by phylogenetic constraints of plants and AMF, but not by environmental variables. This study suggests the evolutionary processes among woody plants and AMF to be more important than environmental filtering in shaping mycorrhizal community assemblages in subtropical forest ecosystems.

关键词： 454 pyrosequencing 18S r DNA arbuscular mycorrhizal fungi mutualistic network pattern phylogenetic constraint subtropical forest woody plant

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On the combined effect of soil fertility and topography on tree growth in subtropical forest ecosystems—a study from SE China

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Journal of Plant Ecology 2017年第1期10卷 111-127页

作者： Thomas Scholten Philipp Goebes Peter Kühn Steffen Seitz Thorsten Assmann Jürgen Bauhus Helge Bruelheide Francois Buscot Alexandra Erfmeier Markus Fischer Werner Härdtle Jin-Sheng He Keping Ma Pascal A.Niklaus Michael Scherer-Lorenzen Bernhard Schmid Xuezheng Shi Zhengshan Song Goddert von Oheimb Christian Wirth tesfaye Wubet Karsten Schmidt Department of Geosciences Soil Science and GeomorphologyUniversity of TübingenRümelinstraße 19-2372070 TübingenGermany Institute of Ecology Leuphana University LüneburgScharnhorststr.121335 LüneburgGermany Faculty of Forest and Environmental Sciences SilvicultureUniversity of FreiburgTennenbacherstraße 479085 Freiburg im BreisgauGermany Institute of Biology/Geobotany and Botanical Garden Martin Luther University Halle WittenbergAm Kirchtor 106108 HalleGermany German Centre for Integrative Biodiversity Research(iDiv)Halle-Jena-Leipzig Deutscher Platz 5e04103 LeipzigGermany Helmholtz Centre for Environmental Research UFZ Theodor-Lieser-Straße 406120 HalleGermany Department of Plant Sciences University of BernAltenbergrain 213013 BernSwitzerland Peking University No.5 Yiheyuan RoadHaidian DistrictBeijing 100871China Institute of Botany Chinese Academy of SciencesNo.20 NanxincunXiangshanBeijing 100093China Institute of Evolutionary Biology and Environmental Studies University of ZürichWinterthurerstrasse 1908057 ZürichSwitzerland Faculty of Biology Department of GeobotanyUniversity of FreiburgSchänzlestraße 179104 FreiburgGermany Institute of Soil Science Chinese Academy of SciencesNo.71 East Beijing RoadNanjingChina TU Dresden Biodiversity and Nature ConservationPienner Straße 701737 TharandtGermany Department of Systematic Botany and Functional Biodiversity University of LeipzigJohannisallee 2104103 LeipzigGermany

Aims The aim of our research was to understand small-scale effects of topography and soil fertility on tree growth in a forest biodiversity and ecosystem functioning(BEF)experiment in subtropical SE *** Geomorphometric terrain analyses were carried out at a spatial resolution of 5×5 *** samples of different depth increments and data on tree height were collected from a total of 566 plots(667 m2 each).The soils were analyzed for carbon(soil organic carbon[SOC]),nitrogen,acidity,cation exchange capacity(CEC),exchangeable cations and base saturation as soil fertility *** plots were classified into geomorphological *** of variance and linear regressions were applied to all terrain,soil fertility and tree growth *** Findings In general,young and shallow soils and relatively small differences in stable soil properties suggest that soil erosion has truncated the soils to a large extent over the whole area of the *** explains the concurrently increasing CEC and SOC stocks downslope,in hollows and in ***,colluvial,carbon-rich sediments are missing widely due to the convexity of the footslopes caused by uplift and removal of eroded sediments by adjacent *** results showed that soil fertility is mainly influenced by ***-Carlo flow accumulation(MCCA),curvature,slope and aspect significantly affected soil ***,soil fertility was affected by the different geomorphological positions on the experimental sites with ridge and spur positions showing lower exchangeable base cation contents,especially potassium(K),due to *** geomorphological effect of soil fertility is most pronounced in the topsoil and decreases when considering the subsoil down to 50 cm *** soil fertility attributes affect tree height after 1-2 years of growth,among which C stocks proved to be most important while pH_(KCl)and CEC only played minor ***,soil acidity and a hig

关键词： soil fertility topography soil erosion matter transport biodiversity DSM carbon stocks tree forest BEF-China China

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National Forest Inventories capture the multifunctionality of managed forests in Germany

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Forest Ecosystems 2021年第1期8卷 50-68页

作者： Nadja K.Simons María R.Felipe-Lucia Peter Schall Christian Ammer Jürgen Bauhus Nico Blüthgen Steffen Boch François Buscot Markus Fischer Kezia Goldmann Martin M.Gossner Falk Hänsel Kirsten Jung Peter Manning Thomas Nauss Yvonne Oelmann Rodica Pena Andrea Polle Swen C.Renner Michael Schloter Ingo Schöning Ernst-Detlef Schulze Emily F.Solly Elisabeth Sorkau Barbara Stempfhuber tesfaye Wubet Jörg Müller Sebastian Seibold Wolfgang W.Weisser Terrestrial Ecology Research Group Technische Universität MünchenHans-Carl-von-Carlowitz-Platz 285354 FreisingGermany Present address:Ecological Networks Technische Universität DarmstadtSchnittspahnstraße 364287 DarmstadtGermany Helmholtz Centre for Environmental Research-UFZ Department of Ecosystem ServicesDeutscher Platz 5e04103 LeipzigGermany Present address:German Centre for Integrative Biodiversity Research(iDiv)Halle-Jena-Leipzig Deutscher Platz 5e04103 LeipzigGermany Silviculture and Forest Ecology of the Temperate Zones University of GöttingenBüsgenweg 137077 GöttingenGermany Centre for Biodiversity and Sustainable Land-use University of GöttingenBüsgenweg 137073 GöttingenGermany Chair of Silviculture Faculty of Environment and Natural ResourcesUniversity of FreiburgTennenbacherstr.479106 FreiburgGermany Ecological Networks Technische Universität DarmstadtSchnittspahnstraße 364287 DarmstadtGermany Institute of Plant Sciences University of BernAltenbergrain 213013 BernSwitzerland Biodiversity and Conservation Biology WSL Swiss Federal Research InstituteZürcherstrasse 1118903 BirmensdorfSwitzerland Helmholtz Centre for Environmental Research-UFZ Department of Soil EcologyTheodor-Lieser-Straße 406120 Halle(Saale)Germany German Centre for Integrative Biodiversity Research(iDiv)Halle-Jena-Leipzig Deutscher Platz 5e04103 LeipzigGermany Forest Entomology WSL Swiss Federal Research InstituteZürcherstrasse 1118903 BirmensdorfSwitzerland Department of Environmental Systems Science Institute of Terrestrial EcosystemsETH ZürichUniversitätstr 168092 ZürichSwitzerland Environmental Informatics University of MarburgDeutschhausstraße 1235032 MarburgGermany Evolutionary Ecology and Conservation Genomics Ulm UniversityAlbert-Einstein-Allee 1189069 UlmGermany Senckenberg Biodiversity and Climate Research Centre Senckenberganlage 2560325 Frankfurt am MainGermany Geoecology University of TübingenRümelinstraße 19-2372070 TübingenGermany Present address:Department of Sustaina

Background:Forests perform various important ecosystem functions that contribute to ecosystem *** many parts of the world,forest management has shifted from a focus on timber production to multi-purpose forestry,combining timber production with the supply of other forest ecosystem ***,it is unclear which forest types provide which ecosystem services and to what extent forests primarily managed for timber already supply multiple ecosystem *** on a comprehensive dataset collected across 150 forest plots in three regions differing in management intensity and species composition,we develop models to predict the potential supply of 13 ecosystem *** use those models to assess the level of multifunctionality of managed forests at the national level using national forest inventory ***:Looking at the potential supply of ecosystem services,we found trade-offs(*** both bark beetle control or dung decomposition and both productivity or soil carbon stocks)as well as synergies(*** temperature regulation,carbon storage and culturally interesting plants)across the 53 most dominant forest types in *** single forest type provided all ecosystem services *** ecosystem services showed comparable levels across forest types(*** or richness of saprotrophs),while others varied strongly,depending on forest structural attributes(*** availability or cover of edible plants)or tree species composition(*** nitrification activity).Variability in potential supply of ecosystem services was only to a lesser extent driven by environmental ***,the geographic variation in ecosystem function supply across Germany was closely linked with the distribution of main tree ***:Our results show that forest multifunctionality is limited to subsets of ecosystem *** importance of tree species composition highlights that a lack of multifunctionality at the stand lev

关键词： Ecosystem processes and services Forest management Structural diversity Tree species composition Trade-offs and synergies Forest productivity

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Surveillance of drug resistance tuberculosis based on reference laboratory data in Ethiopia

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Infectious Diseases of Poverty 2019年第3期8卷 107-107页

作者： Getu Diriba Abebaw Kebede Habteyes Hailu Tola Ayinalem Alemu Mengistu Tadesse Epherem tesfaye Zemedu Mehamed Abiyot Meaza Bazezew Yenew Hilina Molalign Biniyam Dagne Waganeh Sinshaw Misikir Amare Shewki Moga Yeshiwork Abebaw Getachew Sied Ethiopian Public Health Institute Addis AbabaEthiopia

Background:Both passive and active surveillance of drug resistance have an important role in tuberculosis(TB)control *** data are important to estimate the magnitude of drug resistance TB,to know the trend of the disease,assess the performance of the program,and to forecast diagnosis and treatment ***,this study aimed to determine the prevalence and the proportion of drug resistant tuberculosis in Ethiopia based on passively collected ***:A cross-sectional study was conducted at the National Tuberculosis Reference Laboratory and seven Regional TB laboratories in Ethiopia on a retrospective data collected from July 2017 to June,*** were collected by standardized checklist from TB culture laboratory registration *** of recovery rate,contamination rate,and prevalence of drug resistance TB were determined by Statistical Package for Social Science(SPSS)version ***:Of 10134 TB suspected individuals included into this analysis,1183(11.7%)were culture *** overall contamination proportion was 53%and nontuberculous mycobacteria proportion was 0.98%.First-line drug susceptibility test was performed for 329 M ycobacterium tuberculosis complex isolates,and the proportion of resistance was 5.7 and 6.3%for isoniazid and rifampicin *** proportion of multidrug-resistant tuberculosis(MDR-TB)was 4.3%in new patients,while 6.7%in previously treated ***,there was no category for 0.6%patients,and the overall proportion of MDR-TB was 11.6%.Conclusions:The result of this study indicated that MDR-TB is a serious public health problem in ***,strengthen prevention and control program is vital to halt the burden of drug resistant TB in the country.

关键词： Tuberculosis Multidrug-resistant tuberculosis Rifampicin resistance Isoniazid resistance

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Community assembly of ectomycorrhizal fungi along a subtropical secondary forest succession

Community assembly of ectomycorrhizal fungi along a subtropi...

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中国菌物学会2015年学术年会

作者： Gao Cheng Zhang Yu Shi Nan-Nan Zheng Yong Chen Liang Wubet tesfaye Bruelheide Helge Both Sabine Buscot Francois Ding Qiong Erfmeier Alexander Kuhn Peter Nadrowski Karin Scholten Thomas Guo Liang-Dong State Key Laboratory of Mycology Institute of MicrobiologyChinese Academy of Sciences College of Life Science and Engineering Qiqihar University University of Chinese Academy of Sciences Department of Soil Ecology UFZ-Helmholtz Centre for Environmental Research Institute of Biology Martin Luther University Institute of Biology Leipzig University Department of Geoscieneces Research Area GeographyUniversity of Tubingen

Environmental selection and dispersal limitation are two of the primary processes structuring biotic communities in ecosystems, but little is known about these processes in shaping soil microbial communities during secondary forest succession. We examined the communities of ectomycorrhizal（EM） fungi in young, intermediate and old forests in a Chinese subtropical ecosystem, using 454 pyrosequencing. The EM fungal community consisted of 393 operational taxonomic units（OTUs）, belonging to 21 EM fungal lineages, in which three EM fungal lineages and 11 EM fungal OTUs showed significantly biased occurrence among the young, intermediate and old forests. The EM fungal community was structured by environmental selection and dispersal limitation in old forest, but only by environmental selection in young, intermediate, and whole forests. Furthermore, the EM fungal community was affected by different factors in the different forest successional stages, and the importance of these factors in structuring EM fungal community dramatically decreased along the secondary forest succession series. This study suggests that different assembly mechanisms operate on the EM fungal community at different stages in secondary subtropical forest succession.

关键词： 454 pyrosequencing dispersal limitation ectomycorrhizal(EM) fungal community ITS2 plant community subtropical secondary forest succession

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先天性鱼鳞癣样红皮病患者SPINK5的突变:分子检测是诊断内瑟顿综合征(伴有结节毛的鱼鳞癣)的有效工具

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世界核心医学期刊文摘（皮肤病学分册） 2005年第2期1卷 34-34页

作者： Sprecher E. tesfaye-Kedjela A. Ratajczak P. 马慧群 Department of Dermatology Laboratory of Molecular Dermatology Rambam Medical Center Haifa Israel

The congenital erythrodermas represent a heterogeneous group of inherited and acquired disorders often accompanied by systemic infections, impaired epidermal barrier function and concomitant life-threatening fluid and electrolyte imbalance. In the present report, we describe a patient who was considered to have congenital ichthyosiform erythroderma for 26 years until molecular testing led to the correct diagnosis of Netherton syndrome.

关键词：鱼鳞癣 SPINK5 红皮病分子检测屏障功能文章报道电解质失衡

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