Observation of indirect ionization of W7+ in an electron-beam ion-trap plasma

In this work, visible and extreme ultraviolet spectra of W7+ are measured using the high-temperature superconducting electron-beam ion trap (EBIT) at the Shanghai EBIT Laboratory under extremely low-energy conditions (lower than the nominal electron-beam energy of 130 eV). The relevant atomic structure is calculated using the flexible atomic code package based on the relativistic configuration interaction method. The GRASP2K code, in the framework of the multiconfiguration Dirac-Hartree-Fock method, is employed as well for calculating the wavelength of the M1 transition in the ground configuration of W7+. A line from the W7+ ions is observed at a little higher electron-beam energy than the ionization potential for W4+, making this line appear to be from W5+. A hypothesis for the charge-state evolution of W7+ is proposed based on our experimental and theoretical results; that is, the occurrence of W7+ ions results from indirect ionization caused by stepwise excitation between some metastable states of lower-charge-state W ions, at the nominal electron-beam energy of 59 eV

On the energy-delay tradeoff and relay positioning of wireless butterfly networks

This paper considers energy-delay tradeoff (EDT) of data transmission in wireless network coded butterfly networks (WNCBNs) where two sources convey their data to two destinations with the assistance of a relay employing either physical-layer network coding (PNC) or analog network coding (ANC). Hybrid automatic repeat request with incremental redundancy (HARQIR) is applied for a reliable communication. Particularly, we first investigate the EDT of both PNC and ANC schemes in WNCBNs to evaluate their energy efficiency. It is found that there is no advantage of using a relay in a high power regime. However, in a low power regime, the PNC scheme is shown to be more energy efficient than both the ANC and direct transmission (DT) schemes if the relay is located far from the sources, while both the PNC and ANC schemes are less energy efficient than the DT scheme when the relay is located near the sources. Additionally, algorithms that optimise relay positioning are developed based on two criteria - minimising total transmission delays and minimising total energy consumption subject to node location and power allocation constraints. This optimisation can be considered as a benchmark for relay positioning in either a low-latency or a low-energy-consumption WNCBN

Resolving urban mobility networks from individual travel graphs using massive-scale mobile phone tracking data

Human movements and interactions with cities are characterized by urban mobility networks. Many studies that address urban mobility are inspired by complex networks. The models of complex networks require a large amount of empirical data. However, current works relied on traditional survey data and were unable to take full advantage of the capabilities offered by complex networks; thus, the possibility of quantifying urban mobility networks by considering individual travel patterns has not yet been addressed. This study presents a data-driven approach for characterizing urban mobility networks based on massive-scale mobile phone tracking data. Individual travel motifs are first extracted using a graph-based approach. The global urban mobility network (G-UMN) and the motif-dependent urban mobility subnetworks (MD-UMNs) are then constructed. Next, network properties, including statistical measures and scaling relations between the basic measures, are proposed for characterizing mobility networks. We have conducted experiments focusing on Shenzhen, China. The results demonstrated that (1) the individual travel motifs are structurally and spatially heterogeneous, (2) the G-UMN exhibits a evolutionary hierarchical structure, and (3) the MD-UMNs show many behavioral differences in their spatial and topological properties, reflecting the impacts of the heterogeneity of the individual travel motifs. These results bridge the gap between complex network properties and urban mobility patterns and provide crucial implications and policies for data-informed urban planning

Alterations of coronary perfusion pressure and cardiac contraction during lipopolysaccharide challenge

In the present study, we used the Langendorff technique to evaluate the involvement of endothelin-1 (ET-I) and nitric oxide (NO) in coronary vasoconstriction and myocardial depression in hearts isolated from lipopolysaccharide (LPS)-treated rats. Coronary perfusion pressure (CPP) increased markedly in hearts from LPS -treated rats. Pretreatment with BQ-123, an ET-1 type A receptor antagonist, significantly reduced the increase in CPP induced by LPS. LPS induced a marked decrease in left ventricular developed pressure, the product of left ventricular developed pressure and heart rate, as well as the maximal rate of rise/fall of left ventricular pressure. Pretreatment with BQ-123 partially reversed the LPS-induced cardiac depression. Administration of BQ-123 and AMG, an inhibitor of iNOS, prior to LPS challenge significantly blocked the negative inotropic effect. These results suggest that ET-1 augments the NO-mediated cardiac contractile depression induced by LPS and the accompanying increase in coronary resistance.published_or_final_versio

Antiviral treatment alters the frequency of activating and inhibitory receptor-expressing natural killer cells in chronic Hepatitis B virus infected patients

Natural killer (NK) cells play a critical role in innate antiviral immunity, but little is known about the impact of antiviral therapy on the frequency of NK cell subsets. To this aim, we performed this longitudinal study to examine the dynamic changes of the frequency of different subsets of NK cells in CHB patients after initiation of tenofovir or adefovir therapy. We found that NK cell numbers and subset distribution differ between CHB patients and normal subjects; furthermore, the association was found between ALT level and CD158b+ NK cell in HBV patients. In tenofovir group, the frequency of NK cells increased during the treatment accompanied by downregulated expression of NKG2A and KIR2DL3. In adefovir group, NK cell numbers did not differ during the treatment, but also accompanied by downregulated expression of NKG2A and KIR2DL3. Our results demonstrate that treatment with tenofovir leads to viral load reduction, and correlated with NK cell frequencies in peripheral blood of chronic hepatitis B virus infection. In addition, treatments with both tenofovir and adefovir in chronic HBV infected patients induce a decrease of the frequency of inhibitory receptor+ NK cells, which may account for the partial restoration of the function of NK cells in peripheral blood following treatment

Geometric entanglement from matrix product state representations

An efficient scheme to compute the geometric entanglement per lattice site for quantum many-body systems on a periodic finite-size chain is proposed in the context of a tensor network algorithm based on the matrix product state representations. It is systematically tested for three prototypical critical quantum spin chains, which belong to the same Ising universality class. The simulation results lend strong support to the previous claim [Q.-Q. Shi, R. Or\'{u}s, J. O. Fj{\ae}restad, and H.-Q. Zhou, New J. Phys \textbf{12}, 025008 (2010); J.-M. St\'{e}phan, G. Misguich, and F. Alet, Phys. Rev. B \textbf{82}, 180406R (2010)] that the leading finite-size correction to the geometric entanglement per lattice site is universal, with its remarkable connection to the celebrated Affleck-Ludwig boundary entropy corresponding to a conformally invariant boundary condition.Comment: 4+ pages, 3 figure

Vasorelaxant effect of total flavones from Dendranthema morifolium on rat thoracic aorta

To investigate the vasorelaxant effect of total flavones from Dendranthema morifolium (Ramat.) Tzvel. cv. Hangju (FDM), tension was recorded from rat thoracic aortic rings. FDM completely relaxed, in a dose-dependent manner, the contractions induced by either phenylephrine (PE) or a high concentration of KCl (60 mM) in rings with intact endothelium. Mechanical removal of the endothelium did not significantly modify the vasorelaxant effect of FDM. In endothelium-denuded aortic rings depolarized by 60 mM KCl, FDM inhibited Ca/sup 2+/-induced contraction. FDM also reduced the transient contraction elicited by PE in Ca/sup 2+/-free medium, but had no effect on active phorbol ester-induced contraction. Pretreatment of endothelium-denuded aorta with propranolol, a beta-adrenoceptor antagonist, significantly attenuated the relaxant effect of FDM. These results indicate that FDM induces an endothelium-independent relaxation in rat aortic rings. The mechanisms may include the activation of beta-adrenergic receptors, reduction in Ca/sup 2+/ influx through the voltage-dependent and receptor-operated channels, and inhibition of intracellular Ca release in vascular smooth muscle cells.published_or_final_versio

Field performance of Xa21 transgenic indica rice (Oryza sativa L.), IR72

Based on the characterization of the resistance phenotype and molecular analysis, several homozygous lines carrying Xa21 against the bacterial blight (BB) pathogen were obtained from previously transformed indica rice, IR72. The homozygous line, T103-10, with the best phenotype and seed-setting, was repeatedly tested under normal field conditions to evaluate its levels of resistance to the BB pathogen in Wuhan, China, in 1998 and 1999. The isolates of Xanthomonas oryzae pv oryzae (Xoo) used in this experiments were PXO61, PXO79, PXO99 and PXO112 isolated from the Philippines, T2 isolated from Japan, and Zhe173 isolated from China. The results demonstrated that the transgenic homozygous line expressed the same resistance spectrum, but with a shorter lesion length to each inoculated isolates as the lesion length of the Xa21 donor line IRBB21. The non-transformed control IR72 carrying Xa4 was resistant to PXO61, PXO112, Zhe173 and T2, but susceptible to PXO99 and PXO79. The negative control variety IR24 was susceptible to all isolates under field conditions. The results demonstrated clearly that the Xa21 transgene led to an excellent field performance of the introduced bacterial blight resistance trait on the recipient plants. The yield performance of this transgenic homozygous line, T103-10, is comparable with that of the control under field conditions

Optimization of enantioselective production of chiral epichlorohydrin catalyzed by a novel epoxide hydrolase from domestic duck liver by response surface methodology

Enantiopure epichlorohydrin is a valuable epoxide intermediate for preparing optically active pharmaceuticals. In the present study, a novel epoxide hydrolase prepared from domestic duck liver was used as biocatalyst for producing (S)-epichlorohydrin which preparation process was optimized by response surface methodology. Response surface methodology was performed to evaluate the effects of reaction temperature, pH and reaction time on production of (S)-epichlorohydrin by the novel epoxide hydrolase. (S)-epichlorohydrin production was optimized by Box-Behnken. Three reaction parameters were optimized as follows: pH value 7.10, reaction temperature 32.44°C and reaction time11.06 h. The adequately high R2 value 0.9599 and F score 13.29 indicated the statistical significance of the model. The enantioselective excess of (S)-epichlorohydrin after optimization was 86.14% while thepredicted value was 85.55%. In conclusion, enantioselective hydrolysis conditions optimization to enhance optical purity of (S)-epichlorohydrin could be easily and effectively done by response surfacemethodology; the developed production process indicated the novel epoxide hydrolase from domestic duck liver was high efficient biocatalyst for preparing enantiopure epichlorohydrin

Binary Nonlinearization of Lax pairs of Kaup-Newell Soliton Hierarchy

Kaup-Newell soliton hierarchy is derived from a kind of Lax pairs different from the original ones. Binary nonlinearization procedure corresponding to the Bargmann symmetry constraint is carried out for those Lax pairs. The proposed Lax pairs together with adjoint Lax pairs are constrained as a hierarchy of commutative, finite dimensional integrable Hamiltonian systems in the Liouville sense, which also provides us with new examples of finite dimensional integrable Hamiltonian systems. A sort of involutive solutions to the Kaup-Newell hierarchy are exhibited through the obtained finite dimensional integrable systems and the general involutive system engendered by binary nonlinearization is reduced to a specific involutive system generated by mono-nonlinearization.Comment: 15 pages, plain+ams tex, to be published in Il Nuovo Cimento