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Five new diterpenoid alkaloids, ajacisines A-E (1-5), were isolated from Delphinium ajacis, along with seven known alkaloids (6-12). On the basis of their spectral data (IR, UV, HR-ESI-MS, 1D and 2D NMR) and chemical properties, the structures of compounds 1-12 were identified. All isolated compounds were evaluated for their in vitro antiviral activities against respiratory syncytial virus, and compounds 3-5 and 8 exhibited moderate to weak effects with IC50 values of 75.2 ±1.1, 35.1 ±0.6, 10.1 ±0.3, and 50.2 ±0.5 µM, respectively. [ABSTRACT FROM AUTHOR]

A striking scheme called "counterfactual quantum cryptography" gives a conceptually new approach to accomplish the task of key distribution. It allows two legitimate parties to share a secret even though a particle carrying secret information is not, in fact, transmitted through the quantum channel. Since an eavesdropper cannot directly access the entire quantum system of each signal particle, the protocol seems to provide practical security advantages. However, here we propose an eavesdropping method which works on the scheme in a finite key scenario. We show that, for practical systems only generating a finite number of keys, the eavesdropping can obtain all of the secret information without being detected. We also present a improved protocol as a countermeasure against this attack. [ABSTRACT FROM AUTHOR]

The relationship between lipoxygenase (LOX) pathway-derived volatiles and LOX gene expression was evaluated in kiwifruit [Actinidia deliciosa (A. Chev.) C.F. Liang et A.R. Ferguson var. deliciosa cv. Bruno] during postharvest ripening at 20 °C. The C6 aldehydes n-hexanal and (E)-2-hexenal were abundant in peel compared with flesh tissue and declined as kiwifruit ripened. Esters such as ethyl butanoate and methyl butanoate were lower in the peel than flesh and accumulated when the fruit underwent a climacteric rise in ethylene production. Total LOX activity was higher in the peel than in the flesh and increased as kiwifruit ripened. Expression of AdLox2, AdLox3, AdLox4 and AdLox6 was high in the peel, whereas AdLox1 and AdLox5 showed similar levels in the peel and flesh at the ethylene climacteric. AdLox1 and AdLox5 transcript levels increased and AdLox2, AdLox3, AdLox4 and AdLox6 levels decreased during postharvest fruit ripening. Principal component analysis showed that n-hexanal and (E)-2-hexenal were grouped with LOX genes that were downregulated as kiwifruit ripened. The possible roles of LOX genes in relation to kiwifruit volatile formation during fruit ripening are discussed. [ABSTRACT FROM AUTHOR]

In this paper, we present a theoretical framework of fuzzy reasoning model under quotient space structure. It consists of (1) introducing quotient space structure into fuzzy sets, i.e., constructing fuzzy set representations of different grain-size spaces and their relationships; (2) introducing the concept of fuzzy sets into quotient space theory, i.e., introducing fuzzy equivalence relation and discussing its corresponding reasoning in different grain-size spaces; and (3) discussing the relationship and transformation among different granular computing methodologies. The framework proposed is aimed to combine two powerful abilities in order to enhance the efficiency of fuzzy reasoning: one is the ability of computing with words based on fuzzy set methodology, the other is the ability of hierarchical problem solving based on quotient space approach. [ABSTRACT FROM AUTHOR]

We smear quenched lattice QCD ensembles with lattice volume 32³×8 by using Wilson flow. Six ensembles at temperature near the critical temperature Tc corresponding to the critical inverse coupling βc=6.06173(49) are used to investigate the localization of topological charge density. If the effective smearing radius of Wilson flow is large enough, the density, size and peak of Harrington-Shepard (HS) caloron-like topological lumps of ensembles are stable when β≤6.050, but start to change significantly when β≥6.055. The inverse participation ratio (IPR) of topological charge density shows similar results, it begins to increase when β≥6.055 and is stable when β≤6.050. The pseudoscalar glueball mass is extracted from the topological charge density correlator (TCDC) of ensembles at T=1.19Tc, and 1.36Tc, the masses are 1.915(98) and 1.829(123) GeV respectively, they are consistent with results from conventional methods. [ABSTRACT FROM AUTHOR]

Unmanned aerial vehicles (UAVs) may play an important role in data collection and offloading in vast areas deploying wireless sensor networks, and the UAV's action strategy has a vital influence on achieving applicability and computational complexity. Dynamic programming (DP) has a good application in the path planning of UAV, but there are problems in the applicability of special terrain environment and the complexity of the algorithm. Based on the analysis of DP, this paper proposes a hierarchical directional DP (DDP) algorithm based on direction determination and hierarchical model. We compare our methods with Q-learning and DP algorithm by experiments, and the results show that our method can improve the terrain applicability, meanwhile greatly reduce the computational complexity. [ABSTRACT FROM AUTHOR]

The article offers the author's insights on his study investigating the problems and perception of ancient dwellers of Mesopotamia on the land they dwelt and how landscape change and evolve. The author states that cuneiform lexicography is the most important traditions of ancient Mesopotamian civilization and this serves as elementary carrier for the dwellers to understand such landscape change. He also discusses some of the problems in the reconstruction of the lexical lists.

We study a phenomenological dark energy model which is rooted in the Veneziano ghost of QCD. In this dark energy model, the energy density of dark energy is proportional to Hubble parameter and the proportional coefficient is of the order A3QCD, where AQCQ is the mass scale of QCD. The universe has a de Sitter phase at late time and begins to accelerate at redshift around zacc ∼ 0.6. We lit this model and give the constraints on model parameters, with current observational data including Type la supernovea, baryon acoustic oscillation, cosmic microwave background, big bang nucleosynthesis, and Hubble parameter data. We also study the cosmological evolution of the dark energy with interaction with cold dark matter. [ABSTRACT FROM AUTHOR]

In this note we study the linear dynamics of scalar graviton in a de Sitter background in the infrared limit of the healthy extension of Hořava-Lifshitz gravity with the dynamical critical exponent z = 3. Both our analytical and numerical results show that the nonzero Fourier modes of scalar graviton oscillate with an exponentially damping amplitude on the subhorizon scale, while on the superhorizon scale, the phases are frozen and they approach to some asymptotic values. In addition, as the case of the nonzero modes on superhorizon scale, the zero mode also initially decays exponentially and then approaches to an asymptotic constant value. [ABSTRACT FROM AUTHOR]

In order to solve the problem that previous relation researches in operational task-resource matching are hard to flexible computing for generating a new matching scheme from the existing scheme under the condition of operational tasks or resources adjusted in uncertainty cases, role-based approaches to operational task-resource flexible matching model and algorithm are proposed in the paper for flexible matching operational tasks with resources. Firstly, through introducing the concept of roles, the role-based calculation framework of operational task-resource flexible matching is constructed. Secondly, two aspect indexes about resource utilization ratio (RUR) and time utilization ratio (TUR) are given to reflect operational task-resource matching quality (TRMQ), which can be regarded as the objective function for modeling role-based operational task-resource flexible matching mathematical formulation. On the basis of this, the role-based artificial bee colony (RABC) algorithm, including five specific calculating operators, is put forward for solving the flexible matching problem with double encoding on operational tasks and resources by roles. Finally, via comparing with the previous methods in application cases, it can be validated that role-based model and proposed algorithm are more effective, which can be used to obtain a new incremental scheme from the existing matching scheme for adopting the operational tasks or resources adjustment. Moreover, there are flexible computation advantages of the approaches proposed in this paper to solve the problem about operational task-resource matching in large-scale. [ABSTRACT FROM AUTHOR]

A supramassive, strongly magnetized millisecond neutron star (NS) has been proposed to be the candidate central engine of at least some short gamma-ray bursts (SGRBs), based on the "internal plateau" commonly observed in the early x-ray afterglow. While a previous analysis shows a qualitative consistency between this suggestion and the Swift SGRB data, the distribution of observed break time tb is much narrower than the distribution of the collapse time of supramassive NSs for the several NS equations-of-state (EoSs) investigated. In this paper, we study four recently constructed "unified" NS EoSs (BCPM, BSk20, BSk21, and Shen) as well as three developed strange quark star (QS) EoSs within the new confinement density-dependent mass (CDDM) model, labelled as CIDDM, CDDM1, and CDDM2. All the EoSs chosen here satisfy the recent observational constraints of the two massive pulsars of which the masses are precisely measured. We construct sequences of rigidly rotating NS/QS configurations with increasing spinning frequency f, from nonrotating (f=0) to the Keplerian frequency (f=fK), and provide convenient analytical parametrizations of the results. Assuming that the cosmological NS-NS merger systems have the same mass distribution as the Galactic NS-NS systems, we demonstrate that all except the BCPM NS EoS can reproduce the current 22% supramassive NS/QS fraction constraint as derived from the SGRB data. We simultaneously simulate the observed quantities (the break time tb, the break time luminosity Lb, and the total energy in the electromagnetic channel Etotal) of SGRBs and find that, while equally well reproducing other observational constraints, QS EoSs predict a much narrower tb distribution than that of the NS EoSs, better matching the data. We therefore suggest that the postmerger product of NS-NS mergers might be fast-rotating supramassive QSs rather than NSs. [ABSTRACT FROM AUTHOR]

Ten indole alkaloids (1-10) were obtained from an antifungal extract of Winchia calophylla, of which two (2 and 4) were new. N(4)-Methyl-10-hydroxyl-desacetylakuammilin (2) was an akuammiline-type indole alkaloid. N(1)-Methyl-echitaminic acid (4) was an unusual zwitterion with a basic vincorine-type skeleton. This is the first report of 10 in W. calophylla. The structures of all of the compounds were determined based on spectroscopic data, and their bioactivities were assessed. Compound 1 showed potent activity against the plant pathogenic fungi of Penicillium italicum and Fusarium oxysporum f.sp cubens with IC50 s of 10.4 and 11.5 µM, respectively, and 3 inhibited Rhizoctonia solani with an IC50 of 11.7 µM. Compounds 2 and 4 showed weak cyto-toxicity against the human leukemic cell line HL-60 in vitro with IC50s of 51.4 and 75.3 µM, respectively. Compounds 1 and 2 displayed weak activity against acetylcholinesterase with IC50 s around 61.3 and 52.6 µM, respectively. [ABSTRACT FROM AUTHOR]

In this paper, low-energy scattering of the (D*...*)± meson system is studied within Liischer's finite-size formalism using Nf = 2 twisted-mass gauge field configurations. With three different pion mass values, the 5-wave threshold scattering parameters--namely the scattering length a0 and the effective range r0--are extracted in the JPC = l+- channel. Our results indicate that, in this particular channel, the interaction between the two vector charmed mesons is weakly repulsive in nature and hence it does not support the possibility of a shallow bound state for the two mesons, at least for the pion mass values being studied. However, these results might suffer from undetermined systematic errors due to low-lying states ignored in this exploratory study. Still, it provides some useful information on the nature of the newly discovered resonance-like structure Zc(4025) observed in various experiments. [ABSTRACT FROM AUTHOR]

We present renormalization constants of overlap quark bilinear operators on 2 + 1-flavor domain wall fermion configurations. This setup is being used by the X QCD Collaboration in calculations of physical quantities such as strangeness in the nucleon and the strange and charm quark masses. The scaleindependent renormalization constant for the axial-vector current is computed using the Ward identity. The renormalization constants for scalar, pseudoscalar, and vector currents are calculated in the RI-MOM scheme. Results in the MS scheme are also given. The step scaling function of quark masses in the RI-MOM scheme is computed as well. The analysis uses, in total, six different ensembles of three sea quarks, each on two lattices with sizes 24³ x 64 and 32³ x 64 at spacings a = (1.73 GeV)-1 and (2.28 GeV)-1, respectively. [ABSTRACT FROM AUTHOR]

A high precision high-order curvature-compensated bandgap reference (BGR) compatible with standard BiCMOS process is presented in this paper that is capable of working down to input voltages of 1.6 V with 1.285 V output voltage. High-order curvature correction for this reference is accomplished by a novel piecewise technique, which realizes exponential curvature compensation in temperature range, and a logarithmic compensation term proportional to VT In T in higher temperature range through simple structures. Experimental results of the proposed BGR implemented in 0.5-μm BiCMOS process demonstrate that a temperature coefficient (TC) of 5 ppm/°C is realized at 3.6 V power supply, a power-supply noise attenuation (PSNA) of 70 dB is achieved without filtering capacitors, and the line regulation is better than 0.47 mV/V from 1.6 V to 5 V supply voltage while dissipating a maximum supply current of 25 μA. The active area of the presented BGR is 180 μm × 220 μm. [ABSTRACT FROM PUBLISHER]

We present an exploratory study for charmonium radiative transitions: J/ψ → ηcγ χc0 → J/ψγ, and hc → ηcγ using Nf = 2 twisted-mass lattice QCD gauge configurations. The single-quark vector form factors for ηc and χc0 are also determined. The simulation is performed at a lattice spacing of α = 0.067(2) fm and the lattice size is 32³ x 64 with a pion mass of about 485 MeV. Alter extrapolation of lattice data at nonzero Q² to 0, we compare our results with previous quenched lattice results and the available experimental values. [ABSTRACT FROM AUTHOR]

This paper deals with the global convergence and stability of the Hopfield-type neural networks under the critical condition that M1(F) = L-1DF - (FW+WTF)/(2) is nonnegative for any diagonal matrix F, where W is the weight matrix of the network, L = diag(L1, L2,.. . , LN) with 4 being the Lipschitz constant of gi and G(u) = (g1(u1),g2(u2),. . ,gN(uN))T is the activation mapping of the network. Many stability results have been obtained for the Hopfield-type neural networks in the noncritical case that M1 (F) is positive definite for some positive definite diagonal matrix F. However, very few results are available on the global convergence and stability of the networks in the critical case. In this paper, by exploring two intrinsic features of the activation mapping, two generic global convergence results are established in the critical case for the Hopfield-type neural networks, which extend most of the previously known globally asymptotic stability criteria to the critical case. The results obtained discriminate the critical dynamics of the networks, and can be applied directly to a group of Hopfield-type neural network models. An example has also been presented to demonstrate both theoretical importance and practical significance of the critical results obtained. [ABSTRACT FROM AUTHOR]

The flavor-changing neutral current decay processes of the B and Bc mesons with the final states involving spin-1/2 particles are investigated. By considering the background of the Standard Model, where ν̄ν contributes the missing energy and the experimental upper bounds for the branching fractions, we get the constraints of the coupling constants of the quark-antiquark and the assumed invisible particles χ̄χ. The constraints of the coupling constants are then used to study the similar processes of the Bc meson. At some specific region of mχ, the upper limit of BR(Bc→D(s)χ̄χ) is of the order of 10-6, while for BR(Bc→D∗(s)χ̄χ)), it is 10-5. The possibility of distinguishing χ to be a Majorana or Dirac fermion by the differential branching fractions is also discussed. [ABSTRACT FROM AUTHOR]

This paper describes a general method for the manipulation of nuclear spins in zero magnetic field. In the absence of magnetic fields, the spins lose the individual information on chemical shifts and inequivalent spins can only be distinguished by nuclear gyromagnetic ratios and spin-spin couplings. For spin- 1/2 nuclei with different gyromagnetic ratios (i.e., different species) in zero magnetic field, we describe the scheme to realize a set of universal quantum logic gates, e.g., arbitrary single-qubit gates and a two-qubit controlled-not gate. This method allows for universal quantum control in systems which might provide promising applications in materials science, chemistry, biology, quantum information processing, and fundamental physics. [ABSTRACT FROM AUTHOR]