161 research outputs found

    The effect of temperature on the fracture mechanism in 2014A1/15vol.%Al2O3 composite

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    The tensile fracture strain, stress and fracture mode for a discontinuously reinforced aluminum matrix composite, 2014Al/15vol.%Al2O3, were determined and compared with those of the unreinforced matrix material, 2014A1, at various temperatures. Tests were conducted under uniaxial tension at elevated temperatures with a strain rate of 0.1 s-. It was found that the tensile fracture strain as well as fracture stress of the composite were lower than those of the matrix material. The tensile fracture mode changed from transgranular fracture to intergranular fracture between 400 [deg]C and 500 [deg]C for both materials. For the composite, at temperatures below 400 [deg]C the growth and coalescence of voids occurred via a dislocation creep process primarily along the Al---Al2O3 interface. Above 400 [deg]C voids initiated and grew at the Al---Al2O3 interface and grain boundaries via a diffusion creep process. The void growth was found not along the tensile direction but along the Al---Al2O3 interface and grain boundaries, and this resulted in a low fracture strain. A method for determining quantitatively the characteristics of the void initiation and growth is discussed.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/31436/1/0000354.pd

    Hierarchical colour image segmentation by leveraging RGB channels independently

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    In this paper, we introduce a hierarchical colour image segmentation based on cuboid partitioning using simple statistical features of the pixel intensities in the RGB channels. Estimating the difference between any two colours is a challenging task. As most of the colour models are not perceptually uniform, investigation of an alternative strategy is highly demanding. To address this issue, for our proposed technique, we present a new concept for colour distance measure based on the inconsistency of pixel intensities of an image which is more compliant to human perception. Constructing a reliable set of superpixels from an image is fundamental for further merging. As cuboid partitioning is a superior candidate to produce superpixels, we use the agglomerative merging to yield the final segmentation results exploiting the outcome of our proposed cuboid partitioning. The proposed cuboid segmentation based algorithm significantly outperforms not only the quadtree-based segmentation but also existing state-of-the-art segmentation algorithms in terms of quality of segmentation for the benchmark datasets used in image segmentation. © 2019, Springer Nature Switzerland AG

    Extremely stable graphene electrodes doped with macromolecular acid

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    Although conventional p-type doping using small molecules on graphene decreases its sheet resistance (Rsh), it increases after exposure to ambient conditions, and this problem has been considered as the biggest impediment to practical application of graphene electrodes. Here, we report an extremely stable graphene electrode doped with macromolecular acid (perfluorinated polymeric sulfonic acid (PFSA)) as a p-type dopant. The PFSA doping on graphene provides not only ultra-high ambient stability for a very long time (> 64 days) but also high chemical/thermal stability, which have been unattainable by doping with conventional small-molecules. PFSA doping also greatly increases the surface potential (similar to 0.8 eV) of graphene, and reduces its Rsh by similar to 56%, which is very important for practical applications. High-efficiency phosphorescent organic light-emitting diodes are fabricated with the PFSA-doped graphene anode (similar to 98.5 cd A(-1) without out-coupling structures). This work lays a solid platform for practical application of thermally-/chemically-/air-stable graphene electrodes in various optoelectronic devices

    Severe Exercise and Exercise Training Exert Opposite Effects on Human Neutrophil Apoptosis via Altering the Redox Status

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    Neutrophil spontaneous apoptosis, a process crucial for immune regulation, is mainly controlled by alterations in reactive oxygen species (ROS) and mitochondria integrity. Exercise has been proposed to be a physiological way to modulate immunity; while acute severe exercise (ASE) usually impedes immunity, chronic moderate exercise (CME) improves it. This study aimed to investigate whether and how ASE and CME oppositely regulate human neutrophil apoptosis. Thirteen sedentary young males underwent an initial ASE and were subsequently divided into exercise and control groups. The exercise group (n = 8) underwent 2 months of CME followed by 2 months of detraining. Additional ASE paradigms were performed at the end of each month. Neutrophils were isolated from blood specimens drawn at rest and immediately after each ASE for assaying neutrophil spontaneous apoptosis (annexin-V binding on the outer surface) along with redox-related parameters and mitochondria-related parameters. Our results showed that i) the initial ASE immediately increased the oxidative stress (cytosolic ROS and glutathione oxidation), and sequentially accelerated the reduction of mitochondrial membrane potential, the surface binding of annexin-V, and the generation of mitochondrial ROS; ii) CME upregulated glutathione level, retarded spontaneous apoptosis and delayed mitochondria deterioration; iii) most effects of CME were unchanged after detraining; and iv) CME blocked ASE effects and this capability remained intact even after detraining. Furthermore, the ASE effects on neutrophil spontaneous apoptosis were mimicked by adding exogenous H2O2, but not by suppressing mitochondrial membrane potential. In conclusion, while ASE induced an oxidative state and resulted in acceleration of human neutrophil apoptosis, CME delayed neutrophil apoptosis by maintaining a reduced state for long periods of time even after detraining

    Measurement of the mass difference m(D-s(+))-m(D+) at CDF II

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    We present a measurement of the mass difference m(D-s(+))-m(D+), where both the D-s(+) and D+ are reconstructed in the phipi(+) decay channel. This measurement uses 11.6 pb(-1) of data collected by CDF II using the new displaced-track trigger. The mass difference is found to be m(D-s(+))-m(D+)=99.41+/-0.38(stat)+/-0.21(syst) MeV/c(2)

    Virologie / Bakteriologie / Mykologie

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    141 - Effizienz von Kaliumhypochlorit zur Inaktivierung ausgewählter pilzlicher, bakterieller und viraler PflanzenkrankheitserregerEfficancy of Potassium Hypochlorite (KClO) to inactivate selected plant pathogenic fungi, bacteria and virusesMarlon-Hans Rodríguez, Martina Bandte, Gerhard Fischer, Carmen Büttner142 - Eignung von elektrolytisch generiertem Kaliumhypochlorit zur Inaktivierung von Pflanzenviren in rezirkulierender Nährlösungen im Gewächshausanbau von TomatenAbility of electrolysed produced Potassium Hypochlorite (KClO) to inactivate plant viruses in recirculating nutrient solutions in greenhouse production of tomatosJanine Paulke, Martina Bandte, Carmen Büttner143 - Ultrafiltration und Ultrazentrifugation zur Konzentrierung von Pflanzenviren in NährlösungUltrafiltration and ultracentrifugation as tools to concentrate plant viruses in nutrient solutionJanina Vincenz, Martina Bandte, Carmen Büttner144 - Reinigung doppelsträngiger RNA in Verbindung mit Hochdurchsatzsequenzierung als Werkzeug zum Nachweis von RNA Viren in PflanzenThe combination of double-stranded RNA isolation and deep sequencing as an unspecific diagnostic tool to assess the presence of RNA viruses in plantsTill Lesker, Paul Rentz, Edgar Maiss145 - Impact of silica supplementation on virus infected cucumber culturesRolle der Kieselsäureapplikation Virus infizierter GurkenkulturenSabine Holz, Grzegorz Bartoszewski , Michael Kube, Carmen Büttner146 - Untersuchungen zum Auftreten des Arabis mosaic virus in Birken aus Rovaniemi (Finnland) mit Virus-spezifischen SymptomenInvestigations on the occurence of Arabis mosaic virus in birches from Rovaniemi (Finland) with virus-specific symptomsRichard Pauwels, Markus Rott, Susanne von Bargen, Carmen Büttner147 - Cherry leaf roll virus in Betula spp. in Finland: what do we know about its population diversity?Cherry leaf roll virus in Birken-Arten in Finnland: Was wissen wir über die Populationsdiversität?A. Rumbou, S. von Bargen, M. Rott, R. Jalkanen, C. Büttner148 - Viruserkrankungen im WeinbauViroses in viticultureHenriette Gruber, Patricia Bohnert, Christiane Rieger149 - Molecular analysis of Tobacco rattle virus isolates from potatoes in various parts of GermanyKerstin Lindner, Renate Koenig150 - Detektion und Diversität des European mountain ash ringspot-associated virus (EMARaV) in Ebereschen (Sorbus aucuparia L.) in NorwegenDetection and variability of European mountain ash ringspot-associated virus (EMARaV) in Sorbus aucuparia L. in NorwayTheresa Büttner, Jenny Robel, Hans-Peter Mühlbach, Susanne von Bargen, Carmen Büttner151 - Charakterisierung des European mountain ash ringspot-associated virus (EMARaV) in Mehlbeerenarten (Sorbus spp.)Characterization of the European mountain ash ringspot-associated virus (EMARaV) in whitebeam species (Sorbus spp.)Luisa Dieckmann, Jenny Robel, Susanne von Bargen, Carmen Büttner152 - Vollständige Genomsequenz eines Carrot virus S Isolates aus Meerfenchel aus SpanienW. Menzel, P. Menzel, S. Winter153 - Nachweis und vollständige Sequenzierung eines Carla- und eines Potex-virus aus Epiphyullum spec.Detection and complete sequence of a Carla- and Potexvirus in Epiphyllum spec.Edgar Maiss, Paul Rentz, Annette Hohe, Rosa Herbst154 - Analysis of mixed populations of latent viruses of apple and rubbery wood disease of apple using new generation sequencingAnalyse von Mischpopulationen latenter Apfelviren und der Gummiholzkrankheit an Apfel mittels HochdurchsatzsequenzierungVladimir Jakovljevic, Patricia Otten, Jonathon Blake, Wilhelm Jelkmann155 - Experiments on transmission of viroids under glass and longevity of viroid RNA in detached leaves under different storage conditionsThi Thu Vo, Heinz-Wilhelm Dehne, Stephan Winter, Joachim Hamacher156 - Phytoplasmen in Schleswig-HolsteinPhytoplasmas in the state of Schleswig-HolsteinG. Henkel, C. Willmer, M. Wunderlich, B. Golecki157 . Phytoplasmen verändern das Dufststoffbouquet ihres pflanzlichen LebensraumsPlant volatile emission is affected by phytoplasma infectionMargit Rid, Kai Lukat, Svenja Hoferer, Jürgen Gross159 - Ist das Wurzelbild ein Sortierungsmerkmal für durch Candidatus Phytoplasma pyri verursachten Birnenverfall?Is the root file a sorting feature for Pear decline caused by Canditatus Phytoplama pyri?Georg Henkel, Claudia Willmer, Bernd Kaland, Bettina Golecki160 - Die Bedeutung von β-Caryophyllen als Lockstoff für die Apfeltriebsucht übertragende Blattsaugerart Cacopsylla pictaThe impact of β-caryophyllene as attractant for the Apple Proliferation transmitting insect Cacopsylla pictaConstanze Mesca, Svenja Hoferer, Jürgen Gross161 - Echte Mehltauarten an Beet- und BalkonpflanzenSpecies of powdery mildews on bedding plantsUlrike Brielmaier-Liebetanz162 - Echter Mehltau an Petersilie – Untersuchungen zum WirtspflanzenspektrumPowdery Mildew of Parsley – studies on the host rangePeggy Marx, Ute Gärber163 - Falscher Mehltau an Petersilie – Untersuchungen zum Wirtspflanzenspektrum und molekularbiologische CharakterisierungDowny mildew of parsley – studies on the host range and molecular characterizationGabriele Leinhos, Hermann-Josef Krauthausen, Frank Brändle164 - Welkekrankheit an Euonymus japonicaWilt disease on Euonymus japonicaUlrike Brielmaier-Liebetanz, Roswitha Ulrich, Stefan Wagner, Sabine Werres165 - Taxonomische Analyse der mikrobiellen Gemeinschaft von Zuckerrüben unter unterschiedlichen Lagerbedingungen mittels Hochdurchsatz-Amplikonsequenzierung von unterschiedlichen MarkergenenTaxonomic analysis of the microbial community in stored sugar beets using highthroughput sequencing of different marker genesSebastian Liebe, Daniel Wibberg, Anika Winkler, Alfred Pühler, Andreas Schlüter, Mark Varrelmann166 - Molecular characterization of a novel mycovirus found in Rhizoctonia solani AG 2-2IIIBMolekulare Charakterisierung eines neuen Mycovirus aus Rhizoctonia solani AG 2-2 IIIBAnika Bartholomäus, Mark Varrelman

    Search for a Very Light CP-Odd Higgs Boson in Top Quark Decays from p(p)over-bar Collisions at root s=1.96 TeV

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    We present the results of a search for a very light CP-odd Higgs boson a(1)(0) originating from top quark decays t -> H(+/-)b -> W-+/-(*) a(1)(0)b, and subsequently decaying into tau(+)tau(-). Using a data sample corresponding to an integrated luminosity of 2.7 fb(-1) collected by the CDF II detector in p (p) over bar collisions at 1.96 TeV, we perform a search for events containing a lepton, three or more jets, and an additional isolated track with transverse momentum in the range 3 to 20 GeV/c. Observed events are consistent with background sources, and 95% C.L. limits are set on the branching ratio of t -> H(+/-)b for various masses of H-+/- and a(1)(0)
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