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We investigate the roles of liquidity and delay in financial markets through our proposed optimal forecasting model. The efficiency and liquidity of the financial market are examined using stochastic models that incorporate information delay. Based on machine learning, we estimate the in-sample and out-of-sample forecasting price performances of the six proposed methods using the likelihood function and Bayesian methods, and the out-of-sample prediction performance is compared with the benchmark model ARIMA-GARCH. We discover that the forecasting price performance of the proposed simplified delay stochastic model is superior to that of the benchmark methods by the test methods of a variety of loss function, superior predictive ability test (SPA), Akaike information criterion (AIC), and Bayesian information criterion (BIC). Using data from the Chinese stock market, the best forecasting model assesses the efficiency and liquidity of the financial market while accounting for information delay and trade probability. The rise in trade probability and delay time affects the stability of the return distribution and raises the risk, according to stochastic simulation. The empirical findings show that empirical and best forecasting approaches are compatible, that company size and liquidity (delay time) have an inverse relationship, and that delay time and liquidity have a nonlinear relationship. The most efficient have optimal liquidity.

In this paper, it is theoretically demonstrated that the electromagnetically induced transparency (EIT) and absorption (EIA) can be achieved in a magnetic metamaterial. Unit cell of metamaterial consists of a split ring resonator and an "I" shaped cut-wire pair, which serves as a bright resonator and a dark resonator, respectively. It is found that the EIT effect in metamaterial results from the magnetic interaction between bright and dark resonators. A classical model is also introduced to describe the EIT behavior in magnetic metamaterial, and its analytical results are in good agreement with numerical results. Significantly, by controlling the space separation between resonators, we can obtain the destructive and constructive interferences, and thus observe the transition between EIT and EIA. These results may achieve potential applications on enhancing the nonlinear interaction. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effects of Intron on the EMT capability of non-small cell lung cancer cell line PC-9. Methods: Firstly, using the psiCHECK-2 plasmid as a basic framework to construct the recombinant plasmid of psiCHECK-2-Intron dual-luciferase reporter gene; secondly, the psiCHECK-2-Intron and psiCHECK-2 were transfected into PC-9 cells respectively. The migration and invasion abilities of PC-9 cells were analyzed by Matrigel assay. The expression changes of EMT related hallmarks, including N-cadherin, ß-catenin and snail, were detected by qRT-PCR and Western Blotting. Results: Compared with the control group, the migration and invasion abilities of PC-9 cells in Intron group significantly decreased(p<0.001). The expression of N-cadherin, ß-catenin and snail also down-regulated (p<0.001). Conclusion: The introns could inhibit the EMT of PC-9 cells. [ABSTRACT FROM AUTHOR]

The article presents a complete analysis of an equivalent circuit that functions like the left-handed coplanar-waveguide transmission line element. The characteristics and the effective permittivity of the elements are also determined.

In this paper, a transmissive periodic metasurface based on double-layer metal wire structure is designed by combining gradient phase theory with Pancharatnam-Berry (P-B) phase theory to control scattering phase of electromagnetic wave. The proposed artificial electromagnetic medium lens can improve the cross-polarized wave conversion efficiency of the phase discontinuous metasurface and ensure the thickness of the lens is ultrathin relative to the working wavelength. [ABSTRACT FROM AUTHOR]

Metamaterial absorber (MA) is a hot spot in the research on electromagnetic absorbers. In this paper, a metamaterial based broadband polarization-insensitive absorber is proposed. The absorber is fabricated with FR-4 dielectric substrate foiled with copper. The top layer of the unit cell of the MA is composed of resistors mounted crosswire and gradient split ring resonator (SRR) with a square metal patch (SMP) in it. The overall structure is symmetrical, which makes the MA polarization-insensitive. The gradient SRRs and SMPs resonate at adjacent frequencies resulting in broadband property. The absorption rates of the MA for TE and TM wave are calculated through the simulated S-parameters. The bandwidth is 9.9 GHz, where the absorption rate maintains 60% up to 98.28% in both cases and the relative bandwidth is 57.13%. Both broadband and polarization-insensitivity properties are achieved, which demonstrate promising application prospect of the proposed MA in shielding and stealth technology. [ABSTRACT FROM AUTHOR]

In this paper, we design and numerically demonstrate an electrically controllable light-matter interaction in a hybrid material/metamaterial system consisting of an artificially constructed cross cut-wire complementary metamaterial and an atomically thin graphene layer to realize terahertz (THz) wave modulator. By applying a bias voltage between the metamaterial and the graphene layer, this modulator can dynamically control the amplitude and phase of the transmitted wave near 1.43 THz. Moreover, the distributions of current density show that this large modulation depth can be attributed to the resonant electric field parallel to the graphene sheet. Therefore, the modulator performance indicates the enormous potential of graphene for developing sophisticated THz communication systems. [ABSTRACT FROM AUTHOR]

A series of novel N-tert-butyl sulfinyl squaramide receptors have been designed and synthesized. Their interactions with a range of inorganic anions were studied in solution by ¹H NMR spectroscopy. This new type of squaramide displayed better anion-binding abilities over conventional diphenyl squaramides. The single crystal analysis and DFT calulations implied the role of the tert-butyl C-H protons in binding Cl-. The energies of C-H···Cl- interactions were estimated to be 1.4-1.6 kcal/mol in solution. [ABSTRACT FROM AUTHOR]

N-tert-Butyl sulfinyl squaramides were used for chiral discrimination of a-hydroxyphosphonates using 31P NMR. A free energy relationship study indicates that both steric and the electronic effects influence the chiral recognition of the donors. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to determine whether neutrophil CD64 (nCD64) combined with procalcitonin (PCT), C-reactive protein (CRP) and white blood cell count (WBC) can increase the sensitivity and accuracy of neonatal sepsis diagnosis. Methods: The serum levels of nCD64, CRP, PCT and WBC were detected in 60 patients with neonatal sepsis and 60 patients with non-sepsis. Sensitivity, specificity, positive and negative predictive values, receiver operating characteristic (ROC) area under the curve (AUC), and logistic regression analysis were performed to evaluate the diagnostic value of these markers on neonatal sepsis. Results: Serum levels of nCD64, PCT, CRP and WBC were higher in the sepsis group than non-sepsis group (p < 0.001). The sensitivities of nCD64, PCT, CRP and WBC at the recommended cut-off level for all infants were 79.5%, 68.2%, 38.6% and 52.3%, respectively. The best combination was nCD64 and PCT, which obtained sensitivity of 90.9%, largest AUC of 0.922, and a negative predictive value of 89.2%. However by using an optimal cut-off value, the sensitivities of all four biomarkers for the diagnosis of neonatal sepsis were increased to 95.5%. Except for WBC, the birth weight and gestational age had no effects on the diagnostic value of these serum biomarkers. Conclusions: nCD64 and PCT are better diagnostic biomarkers for early diagnosis of neonatal sepsis as compared to CRP. With the help of optimal cut-off value based on ROC curve and logistic regression analysis, the combination of these biomarkers could improve the sensitivity for the diagnosis of suspected late-onset neonatal sepsis based on common serum biomarkers. [ABSTRACT FROM AUTHOR]

The dynamics of quantum state transfer through a thermal spin chain with Heisenberg interaction is discussed by numerically calculating the maximal fidelity in a finite transfer time for the chains with several numbers of sites. We find that the maximal fidelity does not decrease monotonously with the increase in the temperature, but depends on the maximal allowed transfer time. Finally, we compare the results of thermal channel with the transfer through ground state channel. [ABSTRACT FROM AUTHOR]

We investigate the properties of quantum discord dynamics of a two-qubit Heisenberg XYZ system which is influenced by the environmental decoherence under an external nonuniform magnetic field. It shows that the influence of the parameters on the system heavily rely on the selection of the initial states. One point shows that the environmental decoherence cannot entirely destroy the quantum correlation, and properly controlling the parameters can inhibit the decoherence. Moreover, it presents that the inhomogeneous magnetic field cannot affect the steady quantum discord (QD), while the uniform magnetic field and the anisotropy coupling constant will change the steady QD. These investigations imply that one can obtain larger steady QD values by reasonably adjusting parameters on quantum correlation in solid state systems. [ABSTRACT FROM AUTHOR]

The alternating current (AC) impedance characteristics of silty soil samples have been studied by measuring their AC impedance parameters within the frequency range of 50-106 Hz. The parameters include the real part Z′, imaginary part Z″, impedance module ∣Z∣, and phase difference θ. The effects of the frequency ƒ and the water content w on these parameters are analyzed. The electrical resistivity ρs of silty soil is also calculated, and the relational expression between ρs and w is fitted. Finally, a predication formula of soil w is developed using ρs and ƒ. The results indicate that Z′, -Z″, and ∣Z∣ decrease with increasing logarithm of frequency, log ƒ, and w. Also, θ increases with increasing log ƒ, and θ does not change with w, except at ƒ = 50 and 102 Hz. Given the strong relation of Z′ with w, Z′ of silty soil is primarily determined by the polarizability of free water. In contrast, Z″ of silty soil mainly represents loss from conduction. ∣Z∣ is affected by the polarizability of free water and conduction loss. θ shows the capacitance of the silty soil. At every ƒ, an exponential function is used to simulate soil w increase with decreasing ρs, which has a very high correlation coefficient. Calculated by the predication formula, w is very close to the true w, indicating the reliability of the formula. [ABSTRACT FROM AUTHOR]

We report possibility of generating entanglement and steady entanglement between two identical atoms in free space with a very natural way when their spatial separation is on the order of wavelength or less. We show a dynamical creation of entanglement and steady entanglement due to the radiative coupling with different separable initial atomic states and study the entanglement properties about this atomic subsystem. Not only the creation of steady state entanglement is decided by the initial atomic states, but also the magnitude of the entanglement and the steady state entanglement are found to be strongly dependent on the initial states. We derive a master equation for the atomic subspace and solve it analytically to show how the spontaneous emission from the two atoms system induces entanglement and steady entanglement, the crossing coupling terms in master equation can enhance the entanglement value. [ABSTRACT FROM AUTHOR]

Based on the constitutive tensor of the perfect regular polygonal cloak, the effects of different kinds of losses on the performance of regular polygonal cloak are investigated. The cloak is modeled and simulated using full wave package COMSOL MULTIPHYSICS. It is found that if the loss tangents are imposed on one or more components of constitutive tensors, especially on the off-diagonal components, the performance of the cloak in the backward region is significantly different from the results of the traditional case, in which losses are the same in all components of magnetic and electric loss tangents. We believe that the results are helpful for the practical situations. [ABSTRACT FROM AUTHOR]

By introducing the nonuniform magnetic field, we investigate the entanglement teleportation via two-qubit Heisenberg chain. We show that for ferromagnetic chain, the opposite direction magnetic field on the two-qubit chain can excite the teleported entanglement C out, while the uniform magnetic field can not do it. The effect of the uniform magnetic field B and the nonuniform magnetic field b on the threshold temperature T c is also plotted. Our study on the average fidelity of this quantum channel system shows that the magnetic field in opposite direction can result in the ideal average fidelity no matter whether the chain is ferromagnetic or antiferromagnetic. [ABSTRACT FROM AUTHOR]

Using the finite-difference time-domain method models ideal Drude of DNG metamaterials. The Z-transform is applied to model the Drude model that materials characterized by frequency dispersive behavior. Thus, we certificate the DNG metamaterials and its unique characteristics such as negative refraction, convergence, back-wave, phase compensation and verify the existence of DNG Metamaterials. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1411–1414, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23371 [ABSTRACT FROM AUTHOR]