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Growth of Large-Area Single- and Bi-Layer Graphene by Controlled Carbon Precipitation on Polycrystalline Ni Surfaces

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Nano Research 2009年第6期2卷 509-516页

作者： Alfonso Reina stefan thiele Xiaoting Jia Sreekar Bhaviripudi Mildred S.Dresselhaus Juergen A.Schaefer Jing Kong Department of Materials Science and Engineering Massachusetts Institute of TechnologyCambridgeMassachusetts 02139USA Institut für Physik and Institut für Mikro-und Nanotechnologien Technische Universität IlmenauIlmenau 98684Germany Department of Electrical Engineering and Computer Science Massachusetts Institute of TechnologyCambridgeMassachusetts 02139USA Department of Physics Massachusetts Institute of TechnologyCambridgeMassachusetts 02139USA

We report graphene films composed mostly of one or two layers of graphene grown by controlled carbon precipitation on the surface of polycrystalline Ni thin films during atmospheric chemical vapor deposition(CVD).Controlling both the methane concentration during CVD and the substrate cooling rate during graphene growth can signifi cantly improve the thickness *** a result,one-or two-layer graphene regions occupy up to 87%of the fi lm *** layer coverage accounts for 5%11%of the overall fi *** regions expand across multiple grain boundaries of the underlying polycrystalline Ni fi *** number density of sites with multilayer graphene/graphite(>2 layers)is reduced as the cooling rate *** fi lms can also be transferred to other substrates and their sizes are only limited by the sizes of the Ni fi lm and the CVD ***,we demonstrate the formation of fi lms as large as 1 in^(2).These fi ndings represent an important step towards the fabrication of large-scale high-quality graphene samples.

关键词： Graphene chemical vapor deposition nickel catalyst carbon nanomaterials

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How do altitude and soil properties influence the taxonomic and phylogenetic structure and diversity of Brazilian páramo vegetation?

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Journal of Mountain Science 2020年第5期17卷 1045-1057页

作者： Markus GASTAUER Jan thiele stefan POREMBSKI Andreza Viana NERI Instituto Tecnologico Vale R.Boaventura da Silva955CEP 66055-090Bairro NazareBelemPABrazil Universidade Federal do Para Programa de pos-graduacao em EcologiaRuaAugusto Correa01CEP 66075-110GuamaBelemBrazil Thünen Institute Institute of BiodiversityBundesallee 6538116 BraunschweigGermany University of Rostock Institute of BioscienceDepartment of Botany and Botanical GardenWismarsche Str.44/45D-18051 RostockGermany Universidade Federal de Vicosa Department of Plant BiologyLaboratory of Ecology and Evolution of PlantsCampus Universitario s/n36570-900VigosaMinas GeraisBrazil

Altitude and environmental variables such as edaphic properties are considered determinants of species distribution and community composition in mountain ***,we aimed to outline the effects of distinct mountain peaks,altitude and soil properties on community composition,species density,phylogenetic structure and diversity of angiosperm páramo communities from the Serra do Brigadeiro State Park,Minas Gerais,southeastern *** that,we identified all angiosperm species found in 300 plots(1 m×1 m)from three mountain peaks,measured soil depth and analyzed soil fertility and texture in each *** reduce the number of soil variables and species composition,we computed principal coordinates based on soil properties and principal coordinates based on species-plot matrix for each ***,we computed the standard effect sizes of the mean phylogenetic pairwise distance and the mean nearest phylogenetic taxon distance for each plot to investigate differences in the degree of relatedness among coexisting *** compared differences in response variables between peaks and modelled them in function of altitude and principle components of soil properties using mixed effect *** density and phylogenetic diversity differed between peaks,but,contrary to the previous findings,no relationships between species richness or phylogenetic diversity and altitude or soil properties were found,indicating that further investigations are necessary to understand the altitude-biodiversity relationship in Brazilian páramo *** composition differed between peaks and depended on altitude,soil properties and interactions between them,indicating that upward shifting of bioclimatic conditions due to climate changes may alter communities of this *** structure differed between peaks and was influenced by altitude and soil *** phylogenetic clustering increased with altitude,eventual upward movements of species in Brazilian

关键词： Mountainous ecosystems Altitudebiodiversity relationship High altitude grasslands Phylogenetic diversity Community assemblage Conservation

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Co-expression of CDX2 and MUC2 in gastric carcinomas: Correlations with clinico-pathological parameters and prognosis

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World Journal of Gastroenterology 2005年第21期11卷 3182-3188页

作者： Kristina Roessler stefan P.M(o|¨)nig Paul M.Schneider Franz-Georg Hanisch Stephanie Landsberg Juergen thiele Arnulf H.H(o|¨)lscher Hans P.Dienes Stephan E.Baldus Institute of Pathology University of Cologne 50931 Cologne Germany Department of Visceral and Vascular Surgery University of Cologne 50931 Cologne Germany Center of Biochemistry University of Cologne Cologne Germany Institute of Pathology University of Cologne 50931 CologneGermany Department of Visceral and Vascular Surgery University of Cologne 50931 Cologne Germany

AIM: To evaluate the role of CDX2 homeobox protein as a predictor for cancer progression and prognosis as well as its correlation with MUC2 expression. CDX2 represents a transcription factor for various intestinal genes (including MUC2) and thus an important regulator of intestinal differentiation, which could previously be identified in gastric carcinomas and intestinal metaplasia. METHODS: Formalin-fixed and paraffin-embedded tissues from 190 gastric carcinoma patients were stained with monodonal antibodies recognizing CDX2 and MUC2, respectively. Immunoreactivity was evaluated semiquantitatively and statistical analyses including x2 tests, uni- and multi-variate survival analyses were performed. RESULTS: CDX2 was mostly expressed in a nuclear or supranuclear pattern,whereas MUC2 showed an almost exclusive supranuclear *** antigens were present in >80% of areas exhibiting intestinal metaplasia. An immunoreactivity in >5% of the tumor area was observed in 57% (CDX2) or in 21% (MUC2) of the *** presence of both molecules did not correlate with WHO, Lauren and Goseki classification (with the exception of a significantly stronger MUC2 expression in mucinous tumors). CDX2 correlated with a lower pT and pN stage in the subgroups of intestinal and stage I cancers and was associated with MUC2 positivity.A prognostic impact of CDX2 or MUC2 was not observed. CONCLUSION: CDX2 and MUC2 play an important role in the differentiation of normal, inflamed, and neoplastic gastric tissues. According to our results, loss of CDX2 may represent a marker of tumor progression in early gastric cancer and carcinomas with an intestinal phenotype.

关键词： CDX2 MUC2 Monoclonal antibody Gastric carcinoma Prognosis

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