1,534 research outputs found

    Abscisic Acid Uridine Diphosphate Glucosyltransferases Play a Crucial Role in Abscisic Acid Homeostasis in Arabidopsis

    Get PDF
    The phytohormone abscisic acid (ABA) is crucial for plant growth and adaptive responses to various stress conditions. Plants continuously adjust the ABA level to meet physiological needs, but how ABA homeostasis occurs is not fully understood. This study provides evidence that UGT71B6, an ABA uridine diphosphate glucosyltransferase (UGT), and its two closely related homologs, UGT71B7 and UGT71B8, play crucial roles in ABA homeostasis and in adaptation to dehydration, osmotic stress, and high-salinity stresses in Arabidopsis (Arabidopsis thaliana). UGT RNA interference plants that had low levels of these three UGT transcripts displayed hypersensitivity to exogenous ABA and high-salt conditions during germination and exhibited a defect in plant growth. However, the ectopic expression of UGT71B6 in the atbg1 (for beta-glucosidase) mutant background aggravated the ABA-deficient phenotype of atbg1 mutant plants. In addition, modulation of the expression of the three UGTs affects the expression of CYP707A1 to CYP707A4, which encode ABA 8 '-hydroxylases; four CYP707As were expressed at higher levels in the UGT RNA interference plants but at lower levels in the UGT71B6:GFP-overexpressing plants. Based on these data, this study proposes that UGT71B6 and its two homologs play a critical role in ABA homeostasis by converting active ABA to an inactive form (abscisic acid-glucose ester) depending on intrinsic cellular and environmental conditions in plants.X113026Ysciescopu

    Toward Enhanced State of Charge Estimation of Lithium-ion Batteries Using Optimized Machine Learning Techniques.

    Full text link
    State of charge (SOC) is a crucial index used in the assessment of electric vehicle (EV) battery storage systems. Thus, SOC estimation of lithium-ion batteries has been widely investigated because of their fast charging, long-life cycle, and high energy density characteristics. However, precise SOC assessment of lithium-ion batteries remains challenging because of their varying characteristics under different working environments. Machine learning techniques have been widely used to design an advanced SOC estimation method without the information of battery chemical reactions, battery models, internal properties, and additional filters. Here, the capacity of optimized machine learning techniques are presented toward enhanced SOC estimation in terms of learning capability, accuracy, generalization performance, and convergence speed. We validate the proposed method through lithium-ion battery experiments, EV drive cycles, temperature, noise, and aging effects. We show that the proposed method outperforms several state-of-the-art approaches in terms of accuracy, adaptability, and robustness under diverse operating conditions

    Role of optimization algorithms based fuzzy controller in achieving induction motor performance enhancement.

    Get PDF
    Three-phase induction motors (TIMs) are widely used for machines in industrial operations. As an accurate and robust controller, fuzzy logic controller (FLC) is crucial in designing TIMs control systems. The performance of FLC highly depends on the membership function (MF) variables, which are evaluated by heuristic approaches, leading to a high processing time. To address these issues, optimisation algorithms for TIMs have received increasing interest among researchers and industrialists. Here, we present an advanced and efficient quantum-inspired lightning search algorithm (QLSA) to avoid exhaustive conventional heuristic procedures when obtaining MFs. The accuracy of the QLSA based FLC (QLSAF) speed control is superior to other controllers in terms of transient response, damping capability and minimisation of statistical errors under diverse speeds and loads. The performance of the proposed QLSAF speed controller is validated through experiments. Test results under different conditions show consistent speed responses and stator currents with the simulation results

    Noiseless Linear Amplification and Distillation of Entanglement

    Full text link
    The idea of signal amplification is ubiquitous in the control of physical systems, and the ultimate performance limit of amplifiers is set by quantum physics. Increasing the amplitude of an unknown quantum optical field, or more generally any harmonic oscillator state, must introduce noise. This linear amplification noise prevents the perfect copying of the quantum state, enforces quantum limits on communications and metrology, and is the physical mechanism that prevents the increase of entanglement via local operations. It is known that non-deterministic versions of ideal cloning and local entanglement increase (distillation) are allowed, suggesting the possibility of non-deterministic noiseless linear amplification. Here we introduce, and experimentally demonstrate, such a noiseless linear amplifier for continuous-variables states of the optical field, and use it to demonstrate entanglement distillation of field-mode entanglement. This simple but powerful circuit can form the basis of practical devices for enhancing quantum technologies. The idea of noiseless amplification unifies approaches to cloning and distillation, and will find applications in quantum metrology and communications.Comment: Submitted 10 June 200

    New ruthenium complexes of fullerene C-60&C-70

    Get PDF
    The new complexes [Ru(NO)(PPh3)](2)(eta(2)-C-m)(m=60 1 or 70 2) have been prepared by heating a solution of C-60(or C-70) with [Ru(NO)(2)(PPh3)(2)] in toluene. They have been characterized by elemental analysis, IR, UV/VIS, XPS, C-13 and P-31 NMR spectroscopy. The photovaltaic effect for the new compounds has been studied

    Resonances in J/ψϕπ+πJ/\psi \to \phi \pi ^+\pi ^- and ϕK+K\phi K^+K^-

    Full text link
    A partial wave analysis is presented of J/ψϕπ+πJ/\psi \to \phi \pi ^+\pi ^- and ϕK+K\phi K^+K^- from a sample of 58M J/ψJ/\psi events in the BES II detector. The f0(980)f_0(980) is observed clearly in both sets of data, and parameters of the Flatt\' e formula are determined accurately: M=965±8M = 965 \pm 8 (stat) ±6\pm 6 (syst) MeV/c2^2, g1=165±10±15g_1 = 165 \pm 10 \pm 15 MeV/c2^2, g2/g1=4.21±0.25±0.21g_2/g_1 = 4.21 \pm 0.25 \pm 0.21. The ϕππ\phi \pi \pi data also exhibit a strong ππ\pi \pi peak centred at M=1335M = 1335 MeV/c2^2. It may be fitted with f2(1270)f_2(1270) and a dominant 0+0^+ signal made from f0(1370)f_0(1370) interfering with a smaller f0(1500)f_0(1500) component. There is evidence that the f0(1370)f_0(1370) signal is resonant, from interference with f2(1270)f_2(1270). There is also a state in ππ\pi \pi with M=179030+40M = 1790 ^{+40}_{-30} MeV/c2^2 and Γ=27030+60\Gamma = 270 ^{+60}_{-30} MeV/c2^2; spin 0 is preferred over spin 2. This state, f0(1790)f_0(1790), is distinct from f0(1710)f_0(1710). The ϕKKˉ\phi K\bar K data contain a strong peak due to f2(1525)f_2'(1525). A shoulder on its upper side may be fitted by interference between f0(1500)f_0(1500) and f0(1710)f_0(1710).Comment: 17 pages, 6 figures, 1 table. Submitted to Phys. Lett.

    First Measurements of eta_c Decaying into K^+K^-2(pi^+pi^-) and 3(pi^+pi^-)

    Full text link
    The decays of eta_c to K^+K^-2(pi^+pi^-) and 3(pi^+pi^-) are observed for the first time using a sample of 5.8X10^7 J/\psi events collected by the BESII detector. The product branching fractions are determined to be B(J/\psi-->gamma eta_c)*B(eta_c-->K^+K^-pi^+pi^-pi^+pi^-)=(1.21+-0.32+- 0.23)X10^{-4},B(J/ψ>gammaetac)B(etac>K0Kˉ0pi+pi)=(1.29+0.43+0.32)X104,B(J/\psi-->gamma eta_c)*B(eta_c-->K^{*0}\bar{K}^{*0}pi^+pi^-)= (1.29+-0.43+-0.32)X10^{-4}, and (J/\psi-->gamma eta_c)* B(eta_c-->pi^+pi^-pi^+pi^-pi^+pi^-)= (2.59+-0.32+-0.48)X10^{-4}. The upper limit for eta_c-->phi pi^+pi^-pi^+pi^- is also obtained as B(J/\psi-->gamma eta_c)*B(eta_c--> phi pi^+pi^-pi^+pi^-)< 6.03 X10^{-5} at the 90% confidence level.Comment: 11 pages, 4 figure

    Evidence for solar cycles in a late Holocene speleothem record from Dongge Cave, China

    Get PDF
    The association between solar activity and Asian monsoon (AM) remains unclear. Here we evaluate the possible connection between them based on a precisely-dated, high-resolution speleothem oxygen isotope record from Dongge Cave, southwest China during the past 4.2 thousand years (ka). Without being adjusted chronologically to the solar signal, our record shows a distinct peak-to-peak correlation with cosmogenic nuclide 14C, total solar irradiance (TSI) and sunspot number (SN) at multi-decadal to centennial timescales. Further cross-wavelet analyses between our calcite δ18O and atmospheric 14C show statistically strong coherence at three typical periodicities of ~80, 200 and 340 years, suggesting important roles of solar activities in modulating AM changes at those timescales. Our result has further indicated a better correlation between our calcite δ18O record and atmospheric 14C than between our record and TSI. This better correlation may imply that the Sun–monsoon connection is dominated most likely by cosmic rays and oceanic circulation (both associated to atmospheric 14C), instead of the direct solar heating (TSI)

    Measurement of the Branching Fraction of J/psi --> pi+ pi- pi0

    Full text link
    Using 58 million J/psi and 14 million psi' decays obtained by the BESII experiment, the branching fraction of J/psi --> pi+ pi- pi0 is determined. The result is (2.10+/-0.12)X10^{-2}, which is significantly higher than previous measurements.Comment: 9 pages, 8 figures, RevTex
    corecore