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Tree water potentials supporting an explanation for the occurrence of Vachellia erioloba in the Namib Desert (Namibia)

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Forest Ecosystems 2017年第4期4卷 303-312页

作者： joachim h. A. Krug Institute for Silviculture and Forest Ecology Georg-August-University of Gottingen Bosgenweg 1 37077 Gottingen Germany

Background： Site-vegetation relations of Vachellia erioloba, Faidherbia albido, Euclea pseudebenus and Tamarix usneoides in two contrasting locations in the Namib Desert （Namibia） were evaluated with the goal to relate soil water availability to the occurrence of trees under hyper-arid conditions, Methods： Plant water potentials were measured using a pressure chamber in the field. Pre-dawn water potentials were assessed to reflect the soil water potential of the rhizosphere. Midday water potentials were measured to assess the strongest negative water potential applied by the sample trees. Results： Pre-dawn water potentials and midday water potentials indicated access to soil water in the rhizosphere and by this, provide an explanation for an occurrence of V. erioloba within the extreme environmental conditions of sand dunes in the Namib Desert. Diurnal ranges seem to reflect more and less suitable stands, in terms of soil water availability, within the sampling sites. While the impact of the ephemeral Kuiseb river on soil water availability was assessed through the four species＇ plant-internal water relations, comparable pre-dawn water potentials of V. erioioba at both sites indicate soil water availability also in the dunes of Namibrand. The extreme midday water potentials of the dune plants possibly show the upper limit of tolerance for V. eriolobo. Conclusions： The preliminary data provide an explanation of the occurrence and distribution of the investigated species in beds of ephemeral rivers and on dunes under the hyper-arid climatic conditions of the Namib Desert and qualify suitability within the assessed sites. Understanding the plant-physiological processes and assessing the plant-internal water potential provides a valuable tool to evaluate soil water availability within the rhizosphere and to describe an adaptation potential of investigated species. The comparability of pre-dawn water potentials at both sites indicates unexpected soil water availability w

关键词： Water potential Arid land Soil water availability Namibia V. erioloba

In Memory of joachim Messing,a Pioneer in Molecular Genetics and Genomics

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Molecular Plant 2019年第11期12卷 1419-1421页

作者： Students and Postdocs of joachim Messing 机构不祥

We grieve the passing of our beloved and respected mentor,colleague,and friend,***(Jo)Messing,a Distinguished University Professor and director of the Waksman Institute of *** made pioneering contributions that underpin the modern fields of molecular genetics and *** invented the,lshotgunn DNA sequencing method along with a set of toolkits for molecular cloning,which he sent out worldwide for free,advancing the genomic era of *** endeavors guided the directions of both fundamental and applications-based research in agriculture,biofuel,and medicine.

关键词： Pioneer passing directions

Impact of renewable energies on the operation and economicsituation of coal fired power stations： Actual situation of coalfired power stations in Germany

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Frontiers in Energy 2017年第2期11卷 119-125页

作者： hans-joachim KRAUTZ Alexander LISK joachim POSSELT Christian KATZER Department for Power Plant Technology Brandenburg University of Technology Cottbus-Senftenberg 03046 Cottbus Gemany

Due to the fluctuating character of the renewable energy sources the demand of conventional power plants for flexibility is increasing. In the recent years, in Germany there has been a fast rise of production capacity of renewable energies, especially from wind turbines, photovoltaic installations, and biomass plants. The installed nominal power of wind turbines is actually (December 2016) 42 GW and of photovoltaic installations 40?GW. The renewable electric energy production in Germany is about 190?TWh/a, which represents a share of 33% of the yearly demand. The increased need for flexibility affects both the power gradients as well as the minimum load of conventional power plants. Due to this flexibility behaviour, conventional power plants are faced with problems concerning the durability of power plant components, corrosion, more maintenance effort and consequently the overall life expectancy. Another consequence of the increasing share of renewable energies is the decreasing full load operating hours, especially of coal fired and gas power plants. Along with decreasing revenues from the energy exchange market, coal fired power plants are faced with new economically challenges.

关键词： flexible load operation minimal load power gradients power plant maintenance corrosion life expectancy

Combinatorial Dyson-Schwinger equations and inductive data types

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Frontiers of physics 2016年第3期11卷 179-193页

作者： joachim Kock Departament de matemhtiques Universitat Autdnoma de Barcelona Spain

The goal of this contribution is to explain the analogy between combinatorial Dyson-Schwinger equations and inductive data types to a readership of mathematical physicists. The connection relies on an interpretation of combinatorial Dyson-Schwinger equations as fixpoint equations for polynomial functors （established elsewhere by the author, and summarised here）, combined with the now-classical fact that polynomial functors provide semantics for inductive types. The paper is expository, and comprises also a brief introduction to type theory.

关键词： Dyson-Schwinger equations type theory inductive types bialgebras polynomialfunctors

Liver Fat Scores for Noninvasive Diagnosis and Monitoring of Nonalcoholic Fatty Liver Disease in Epidemiological and Clinical Studies

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Journal of Clinical and Translational hepatology 2023年第5期11卷 1212-1227页

作者： Mona Reinshagen Stefan Kabisch Andreas F.h.Pfeiffer joachim Spranger Department of Endocrinology and Metabolism Campus Benjamin FranklinCharitéUniversity MedicineBerlinGermany Deutsches Zentrum für Diabetesforschung e.V. Geschäftsstelle am Helmholtz-Zentrum MünchenNeuherbergGermany

Nonalcoholic fatty liver disease(NAFLD)is strongly associated with the metabolic syndrome and type 2 diabetes and independently contributes to long-term *** often asymptomatic but reversible,it would require population-wide screening,but direct diagnostics are either too invasive(liver biopsy),costly(MRI)or depending on the examiner’s expertise(ultrasonography).hepatosteatosis is usually accommodated by features of the metabolic syndrome(***,disturbances in triglyceride and glucose metabolism),and signs of hepatocellular damage,all of which are reflected by biomarkers,which poorly predict NAFLD as single item,but provide a cheap diagnostic alternative when integrated into composite liver fat *** liver index,NAFLD LFS,and hepatic steatosis index are common and accurate indices for NAFLD prediction,but show limited accuracy for liver fat *** indices are rarely *** fibrosis scores are commonly used in clinical practice,but their mandatory reflection of fibrotic reorganization,hepatic injury or systemic sequelae reduces sensitivity for the diagnosis of simple ***-induced liver fat changes are poorly reflected by liver fat indices,depending on the intervention and its specific impact of weight loss on *** limited validity in longitudinal settings stimulates research for new ***,hepatokines,markers of cellular integrity,genetic variants but also simple and inexpensive routine parameters might be potential ***,liver fat indices lack precision for NAFLD prediction or monitoring in individual patients,but in large cohorts they may substitute nonexistent imaging data and serve as a compound biomarker of metabolic syndrome and its cardiometabolic sequelae.

关键词： NAFLD Liver fat indices Fatty liver index Prediction Dietary intervention

Paraesophageal hernia and iron deficiency anemia:Mechanisms,diagnostics and therapy

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World Journal of Gastrointestinal Surgery 2021年第3期13卷 222-230页

作者： Christoph G Dietrich Dolores hübner joachim W heise Department of Internal Medicine Bethlehem Center of HealthStolberg D-52222Germany Department of Radiology Bethlehem Center of HealthStolberg D-52222Germany Department of General and Abdominal Surgery Bethlehem Health CenterStolberg D-52222Germany

There is ample clinical evidence suggesting that the presence of large axial or paraesophageal hernias may lead to iron deficiency ***-called Cameron lesions,as well as other small mucosa erosions,in the sliding area of these diaphragmatic hernias lead to invisible chronic blood loss and consequently to iron *** the spectrum of symptoms in these patients is large,anemia is often not the only indication and typically not the primary indication for surgical correction of diaphragmatic *** treatment with proton pump inhibitors and iron substitution can alleviate anemia,but this is not always *** exclude other possible bleeding sources in the gastrointestinal tract,a comprehensive diagnostic program is necessary and reviewed in this ***,we discuss controversies in the surgical management of paraesophageal hernias.

关键词： Iron deficiency anemia Paraesophageal hernia Upside-down stomach Cameron lesions

A Fresh Look at Dickinsonia:Removing It from Vendobionta

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Acta Geologica Sinica(English Edition) 2006年第5期80卷 636-642页

作者： joachim REITNER Geowissenschaftliches Zentrum Abteilung Geobiologie Universitt Gttingen 37077 Gttingen Germany

The Ediacaran Dickinsonia is well-known for being the only fossil to be assigned to many phyla,ranging from lichens,Cnidaria,Platyhelminthes,Annelida,and a phylum of its own to a nonmetazoan kingdom.A new specimen from the Ediacaran fine-grained sandstone on the Winter Coast of the White Sea in northern Russia,which has an age of ~555 million years ago,preserved convincing internal anatomies of definite animals,comparable with meridional canals of extant ctenophores(comb jellies).Additionally,we reconsidered Dickinsonia as a biradially symmetrical animal rather than a bilateral one as previously *** animal nature of Dickinsonia is,thus,well established and its affinities are most probably allied to *** research is not only removing Dickinsonia from Vendobionta,but also bringing the fossil record of ctenophores forward to 20 million years before the Cambrian “explosion”.

关键词： Dickinsonia Ctenophora Vendobionta metazoan Ediacara biota Ediacaran

The changing himalayan landscape:pine-oak forest dynamics and the supply of ecosystem services

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Journal of Forestry Research 2017年第3期28卷 431-443页

作者： Niyati Naudiyal joachim Schmerbeck Department of Natural Resources TERI UniversityVasantKunjNew Delhi 110070India Chair of Silviculture Institute of Forest SciencesFaculty of Environment and Natural ResourcesUniversity of FreiburgTennenbacher Str.479085 FreiburgGermany

This review summarizes the current state of knowledge on pine and oak forest dynamics in the midmontane central himalayan forest and the ecosystem services associated with these vegetation types. Forest ecosystems play a crucial role in the livelihood of the central himalayas as well as the adjacent plains, providing a number of tangible and intangible ecosystem services, at each stage of succession. The successional sequence starts from warm temperate grasslands, followed by early successional pine forests, mid-successional pine-oak mixed forests and eventually culminating in a late successional oak community. This successional sequence is considerably influenced by disturbances like fire, grazing, and lopping, which maintain the vegetation types in their current form and can act as potential drivers of change. Fire and grazing in grasslands and pine forests inhibit the successional process by hindering the establishment of pioneer and late successional species, respectively. Potential land-cover changes with forest succession can lead to changes in ecosystem services supply. We found that the number of ecosystem services associated with these vegetation types increase from early to late successional community. Current management approaches fail to include the dynamic nature of vegetation, which is essential for maintenance of ecosystem service supply. In conclusion, the trade-offs between ES of global （biodiversity and carbon） and local importance （fuel wood and fodder） have to be examined carefully in order to have effective conservation and management plans for the region.

关键词： Disturbance Ecosystem services himalaya Oak Pine

Forming Process of Strong Anisotropic Material Based on the hydrodynamic Deep Drawing with Radial Pressure

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Journal of Materials Science & Technology 2005年第5期21卷 733-737页

作者： joachim DANCKERT Karl Brian NIELSEN Department of Production Aalborg University Fibigerstraede 16 DK-9220Aalborg DenmarkDepartment of ProductionAalborg University Fibigerstraede 16 DK-9220Aalborg Denmark

The hydrodynamic deep drawing process enables net shape or near net shape forming of complicated sheet metal parts made from difficultly forming materials, such as aluminium or high strength steels. Based on the conventional hydrodynamic deep drawing process, a new process, hydrodynamic deep drawing process, in which radial pressure is applied to the rim of the blank, is proposed. This new process has been analysed using FEM simulations and the obtained results have been compared with the experimental results. The material used in the experiments was Al-Mg-Si alloy, and in the FEM-simulations the elastic-plastic behaviour of Al-Mg-Si alloy was modelled using Barlat＇s 89 yield criteria.

关键词： hydroforming hydrodynamic deep draw Simulation Aluminum alloy