381 research outputs found

    β-aminobutyric acid induces disease resistance against Botrytis cinerea in grape berries by a cellular priming mechanism

    Get PDF
    The present study was performed to investigate the effect of β-aminobutyric acid (BABA) treatment on defence activation in grape berries and to analyse its cellular mechanism. The results implied that BABA treatment at an effective concentration of 20 mM significantly inhibited gray mould rot caused by Botrytis cinerea in grape berries by inducing resistance. Accordingly, 20 mM BABA triggered a priming defence in grape suspension cells, since only the BABA-treated cells exhibited an accelerated ability for augmenting defence responses upon the pathogen inoculation. The primed cellular reactions were related to an early H2O2 burst, prompt accumulation of stilbene phytoalexins and activation of PR genes. Thus, we assume that 20 mM BABA can induce resistance to B. cinerea infection in intact grape berries perhaps via intercellular priming defence. Moreover, the BABA-induced priming defence is verified, because no negative effects on cell growth, anthocyanin synthesis, and quality impairment in either grape cells or intact berries were observed under low pathogenic pressure

    Mesozoic magmatism and granitic dome in the Wugongshan Massif, Jiangxi province and their genetical relationship to the tectonic events in southeast China

    No full text
    In SE China, a Mesozoic granitic dome coeval to extensional tectonics is exposed in the Wugongshan massif. Its center is occupied by Mesozoic granitoids and granitic gneisses, and the E–W-trending Late-Paleozoic–Mesozoic Pingxiang and Anfu basins are located along its northern and southern sides, respectively. In this paper, the petrological, geochemical (major, incompatible, and rare earth elements) and isotopic characteristics of the granitoids and granitic gneisses of this dome allow us to constrain their geodynamic evolution. The Wugongshan Mesozoic K-feldspar-enriched granitoids consist of six granitic bodies and lie within a Paleozoic metamorphic basement. The Caledonian Shanzhuang granodiorite, containing some dioritic enclaves, occurs in the study area and is a calc-alkaline type granodiorite characterised by lower SiO2 and composed of andesine, biotite, quartz, hornblende, magnetite and sphene. The Mesozoic granitoids, either Indosinian plutons or Yanshanian bodies, show a geochemical affinity of peraluminous S-type granite, having higher SiO2, K2O contents, Al>K+Na+2Ca, enriched in Rb, Th and depleted in Eu. They also exhibit LREE-enriched patterns and marked negative Eu anomalies. The Yanshanian plutons also contain characteristic minerals such as sillimanite, garnet and monazite. The Wugongshan Mesozoic granitoids have higher ISr values (0.70981–0.72885) and lower var epsilonNd(T) (−10.6 to −14.7; an average of −12.6) than those of the early Paleozoic Shanzhuang granodiorite. The Mesozoic granitoids were likely derived from ancient sedimentary rocks by partial melting. The Wugongshan Mesozoic granitoids contain three petrological zones, that is, an Early Cretaceous massive granitic zone in the core (Zone I), a foliated granitic zone (Zone II) and a Triassic granitic gneissic zone in the outer-rim (Zone III). The petrological and geochemical features of massive granitoids (Zone I) are similar to those of foliated granites (Zone II) and of granitic gneisses (Zone III) in this Mesozoic dome. Moreover, geometric and kinematic features within the ductile parts (Units 2 and 3) are also similar to those within the brittle part (Unit 1) of the dome. All these features show that the geologic evolution of the Wugongshan doming is a continuous process lasting from Triassic to Early Cretaceous time. Published 40Ar/39Ar and K–Ar ages in the Wugongshan Mesozoic granitic rocks fall into two major age fields, corresponding to two geodynamic events of intracontinental deformation and magmatic activity. The first tectonothermal event, dated at 226–259 Ma on the granitic gneisses in the outer-rim of dome, can be linked to Indosinian collision between the South China plate and the North China plate during Triassic time. The second event took place during the Early Yanshanian, dated at 180–120 Ma on the granites of the core of dome, and are responsible for final doming of the Wugongshan plutons. This event may be related to a westward subduction of the Paleo-Pacific oceanic plate under the SE-China continent during Late Jurassic–Early Cretaceous time

    Period multiplication and chaotic phenomena in atmospheric dielectric-barrier glow discharges

    Get PDF
    In this letter, evidence of temporal plasma nonlinearity in which atmospheric dielectric-barrier discharges undergo period multiplication and chaos using a one-dimensional fluid model is reported. Under the conditions conducive for chaotic states, several frequency windows are identified in which period multiplication and secondary bifurcations are observed. Such time-domain nonlinearity is important for controlling instabilities in atmospheric glow discharges

    Effective Dynamic Range in Measurements with Flash Analog-to-Digital Convertor

    Full text link
    Flash Analog to Digital Convertor (FADC) is frequently used in nuclear and particle physics experiments, often as the major component in big multi-channel systems. The large data volume makes the optimization of operating parameters necessary. This article reports a study of a method to extend the dynamic range of an 8-bit FADC from the nominal 28\rm{2^8} value. By comparing the integrated pulse area with that of a reference profile, good energy reconstruction and event identification can be achieved on saturated events from CsI(Tl) crystal scintillators. The effective dynamic range can be extended by at least 4 more bits. The algorithm is generic and is expected to be applicable to other detector systems with FADC readout.Comment: 19 pages, 1 table, 10 figure

    Dynamic analysis of QTLs for green leaf area duration and green leaf number of main stem in wheat

    Get PDF
    Senescence in a wheat (Triticum aestivum L.) leaf is a programmed degeneration process leading to death. During this process, green leaf area duration (GLAD) and green leaf number of main stem (GLNMS) are gradually reduced. In this study, the two traits of Hanxuan10/Lumai14 DH population at different development stages after anthesis were evaluated under rainfed and irrigated conditions, and QTLs were detected. GLAD and GLNMS of two parents and DH population under rainfed condition were less than those under irrigated condition, and close correlations (P 22-1B-1, QGlad25-1B-1, QGlad28-1B-2 detected under irrigated condition and QGlad25-1B-3, QGlad28-1B-4 mapped under rainfed condition were located at a 20.7 cM marker interval of Xgwm273-EST122 on 1B chromosome. But QTLs for GLNMS were inducibly and specifically expressed at specific developmental stages after anthesis under both water conditions. The findings provide dynamic genetic information related to wheat senescence

    Nernst Effect and Anomalous Transport in Cuprates: A Preformed-Pair Alternative to the Vortex Scenario

    Full text link
    We address those puzzling experiments in underdoped high TcT_c superconductors which have been associated with normal state "vortices" and show these data can be understood as deriving from preformed pairs with onset temperature T∗>TcT^* > T_c. For uncorrelated bosons in small magnetic fields, and arbitrary T∗/TcT^*/T_c, we present the exact contribution to \textit{all} transport coefficients. In the overdoped regime our results reduce to those of standard fluctuation theories (T∗≈TcT^*\approx T_c). Semi-quantitative agreement with Nernst, ac conductivity and diamagnetic measurements is quite reasonable.Comment: 9 pages, 4 figures; Title, abstract and contents modified, new references added, figures changed, one more figure added; to be published on PR

    Symmetry in the insulator - quantum Hall - insulator transitions observed in a Ge/SiGe quantum well

    Full text link
    We examine the magnetic field driven insulator-quantum Hall-insulator transitions of the two dimensional hole gas in a Ge/SiGe quantum well. We observe direct transitions between low and high magnetic field insulators and the ν=1\nu=1 quantum Hall state. With increasing magnetic field, the transitions from insulating to quantum Hall and quantum Hall to insulating are very similar with respect to their transport properties. We address the temperature dependence around the transitions and show that the characteristic energy scale for the high field transition is larger.Comment: 4 page

    Canonical Coordinates and Meson Spectra for Scalar Deformed N=4 SYM from the AdS/CFT Correspondence

    Full text link
    Five supersymmetric scalar deformations of the AdS_5xS^5 geometry are investigated. By switching on condensates for the scalars in the N=4 multiplet with a form which preserves a subgroup of the original R-symmetry, disk and sphere configurations of D3-branes are formed in the dual supergravity background. The analytic, canonical metric for each geometry is formulated and the singularity structure is studied. Quarks are introduced into two of the corresponding field theories using D7-brane probes and the pseudoscalar meson spectrum is calculated. For one of the condensate configurations, a mass gap is found and shown analytically to be present in the massless limit. It is also found that there is a stepped spectrum with eigenstate degeneracy in the limit of small quark masses. In the case of a second, similar deformation, it is necessary to understand the full D3-D7 brane interaction to study the limit of small quark masses. It is seen that simple solutions to the equations of motion for the other three geometries are unlikely to exist.Comment: 16 pages, 7 figures, references added, typos correcte

    Higher order contributions to Rashba and Dresselhaus effects

    Full text link
    We have developed a method to systematically compute the form of Rashba- and Dresselhaus-like contributions to the spin Hamiltonian of heterostructures to an arbitrary order in the wavevector k. This is achieved by using the double group representations to construct general symmetry-allowed Hamiltonians with full spin-orbit effects within the tight-binding formalism. We have computed full-zone spin Hamiltonians for [001]-, [110]- and [111]-grown zinc blende heterostructures (D_{2d},C_{4v},C_{2v},C_{3v} point group symmetries), which are commonly used in spintronics. After an expansion of the Hamiltonian up to third order in k, we are able to obtain additional terms not found previously. The present method also provides the matrix elements for bulk zinc blendes (T_d) in the anion/cation and effective bond orbital model (EBOM) basis sets with full spin-orbit effects.Comment: v1: 11 pages, 3 figures, 8 table
    • …
    corecore