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The inseparability criterion provides a straightforward and efficient method for identifying and quantifying two-mode Gaussian quantum entanglement, making it a crucial tool in quantum optics experiments. However, it is crucial to recognize that the inseparability criterion serves only as a sufficient condition for entanglement assessment, thereby posing a risk of missed detection during evaluation. This paper investigates the use of the inseparability criterion in assessing two-mode squeezed states, with a particular focus on examining missed entanglement detection due to entanglement asymmetry. The results show that when decoherence symmetrically affects both modes, the inseparability criterion effectively detects entanglement. In contrast, when this symmetry is broken, the criterion may fail to identify entanglement, with the likelihood of missed detection increasing with increasing asymmetry. By comparing these results with the positive partial transpose criterion, which serves as a necessary and sufficient condition, the occurrence of missed detections by the inseparability criterion is confirmed. Our research not only provides valuable insights into the application of the inseparability criterion in quantum information tasks but also deepens the understanding of its operational principles and limitations.

Natural gas hydrate is a new energy source with great potential. Studying the seismic response characteristics of natural gas hydrate in permafrost area is crucial to the exploration and development of natural gas hydrate in China's land area. Based on the Kelvin viscoelastic media model, our work establishes a theoretical geological-geophysical model based on the actual geological and stratigraphic conditions of the Qilian Mountain permafrost, uses the staggered-grid finite difference method to perform forward numerical simulation, and performs wave field characteristic analysis and instantaneous seismic attribute extraction of self-excitation and self-receiving seismic records. The results show that the reflected amplitude energy is weaker when the seismic wave passes through the gas hydrate formation. In the range where the instantaneous frequency attribute profile can distinguish the layer thickness, the instantaneous frequency decreases marginally with the increase of the layer thickness. When seismic waves pass through natural gas-bearing formations, the reflected waves show strong reflection characteristics, and the instantaneous frequency energy increases. The instantaneous seismic attribute has better resolution for the wave-impedance interface, especially the instantaneous phase attribute profile. Therefore, the comprehensive analysis of the instantaneous attribute characteristics can provide a basis for the identification and prediction of terrestrial gas hydrates.

In this study, a method for the active shape control for carbon fiber-reinforced polymer (CFRC) reflectors using piezoelectric lead zirconate titanate (PZT) actuators is proposed. According to this method, a finite element model considering higher transverse shear deformation with independent voltage degrees of freedom is formulated by the Hamilton principle. An optimal shape controller that minimizes the discrete root mean square (RMS) error of a reflecting surface is applied. Then, the optimal arrangements of the PZT actuators are determined by numerical optimization methods, which are developed by modifying the classical Genetic Algorithm, with both single and multi-objective optimizations being studied. In the single optimization formulation, the number of actuators is considered as a constraint, and the RMS error of the reflector is regarded as the optimizing target. A hybrid method that combines the gradient projection method with an adaptive Genetic Algorithm is proposed to solve this problem. In the multi-objective optimization, the residual RMS errors and power consumption of the actuators are considered as the optimization targets. Pareto optimal solutions are obtained by an improved multi-objective Genetic Algorithm. Numerical examples are provided to show the effectiveness of the proposed methods.

Abstract Arctigenin (ACT) is a novel anti‐inflammatory lignan extracted from Arctium lappa L, a herb commonly used in traditional Chinese herbal medicine. In this study, we investigated the molecular mechanism whereby ACT inhibits PCV2 infection‐induced proinflammatory cytokine production in vitro and in vivo. We observed that in PCV2 infection+ACT treated PK‐15 cells, proinflammatory cytokine production was significantly reduced, compared to the PCV2‐infected cells. The transfection and luciferase reporter assay confirmed that ACT suppressed NF‐κB signalling pathway activation following PCV2 infection in PK‐15 cells. Furthermore, western blotting demonstrated that ACT suppressed the NF‐κB signal pathway in PCV2 infection‐stimulated PK‐15 cells by inhibiting the translocation of p65 from the cytoplasm to the nucleus and IκBα phosphorylation. BALB/c mice were used as a model to evaluate the anti‐inflammatory effect of ACT in vivo. We found that the BALB/c mice inoculated with PCV2 infection + ACT treated showed a significant reduction of proinflammatory cytokine production in serum, lung and spleen tissue, compared to the PCV2‐infected mice. Western blotting confirmed that ACT suppressed the NF‐κB signal pathway in PCV2‐infected mice by inhibiting the translocation of p65 from the cytoplasm to the nucleus and IκBα phosphorylation in lung tissue. Our studies first demonstrate that ACT inhibits PCV2 infection‐induced proinflammatory cytokine production by suppressing the phosphorylation and nuclear translocation of NF‐κB in vitro and in vivo. These results will help further develop ACT as a Traditional Chinese herbal medicine remedy in the treatment of porcine circovirus‐associated diseases.

Different from ground-based or airborne early warning radar, space-based radar (SBR) possesses large coverage capability. As a result, several discrete strong scatter points from the antenna side-lobe shares the same feature with the real targets in range-Doppler domain, which leads to false alarms when conducting constant false alarm rate (CFAR) detection process, and the detection performance with regard to SBR deteriorates seriously. In this paper, a discrete side-lobe clutter recognition method based on sliding filter response loss is proposed for space-based radar. Firstly, considering both the echo inhomogeneity and the limited degrees of freedom (DOFs) after dimension-reduced space-time adaptive processing (STAP), the sliding window design strategy is employed to segment range cells for the observation scene. Then, the images related to different range segments are registered after clutter suppression, in this way, the candidate target parameters, including the position information and the amplitude information are counted. On this basis, the reliable recognition scheme between the real target and the discrete side-lobe clutter can be realized by comparing these filter response losses. Compared with recent works, experimental results based on real measured data show that the proposed method significantly improves the fault-tolerant discrimination ability, which possesses high robustness in algorithm performance as well as good prospect in engineering application.

Actinobacillus pleuropneumoniae causes porcine pleuropneumonia. The function of the outer membrane protein W gene (ompW) of A. pleuropneumoniae has not been evaluated. Thus a deletion mutant of ompW, ΔompW, was constructed to explore the effect of ompW gene deletion on bacterial growth, biofilm formation, bacterial morphology, oxidative tolerance, susceptibility to antibiotics, and the expression of ribosome synthesis and ABC transporter related genes. Results showed that the ompW gene deletion did not affect biofilm formation and the growth of A. pleuropneumoniae but did affect bacterial morphology during steady growth, oxidative tolerance, and bacterial susceptibility to polymyxin B, kanamycin, and penicillin. The ompW gene deletion also affected the expression of ribosome synthesis and ABC transporter related genes. These results suggested that ompW may regulate the biological phenotype of A. pleuropneumoniae.

The use of optical sensing for in vivo applications is compelling, since it offers the advantages of non-invasiveness, non-ionizing radiation, and real-time monitoring. However, the signal-to-noise ratio (SNR) of the optical signal deteriorates dramatically as the biological tissue increases. Although increasing laser power can improve the SNR, intense lasers can severely disturb biological processes and viability. Quantum sensing with bright squeezed light can make the measurement sensitivity break through the quantum noise limit under weak laser conditions. A bright squeezed light source is demonstrated to avoid the deterioration of SNR and biological damage, which integrates an external cavity frequency-doubled laser, a semi-monolithic standing cavity with periodically poled titanyl phosphate (PPKTP), and a balanced homodyne detector (BHD) assembled on a dedicated breadboard. With the rational design of the mechanical elements, the optical layout, and the feedback control equipment, a maximum non-classical noise reduction of −10.7 ± 0.2 dB is observed. The average squeeze of −10 ± 0.2 dB in continuous operation for 60 min is demonstrated. Finally, the intracavity loss of degenerate optical parametric amplifier (DOPA) and the initial bright squeezed light can be calculated to be 0.0021 and −15.5 ± 0.2 dB, respectively. Through the above experimental and theoretical analysis, the direction of improving bright squeeze level is pointed out.

Abstract Recent advances in battery energy storage technologies enable increasing number of photovoltaic-battery energy storage systems (PV-BESS) to be deployed and connected with current power grids. The reliable and efficient utilization of BESS imposes an obvious technical challenge which needs to be urgently addressed. In this paper, the optimal operation of PV-BESS based power plant is investigated. The operational scenarios are firstly partitioned using a self-organizing map (SOM) clustering based approach. The revenue optimization model is adopted for the PV-BESS power plants to determine the optimal operational modes under typical conditions for a set of considerations, e.g. power generation revenue, assessing rewards/penalties as well as peak shaving/valley filling revenue. The solution is evaluated through a set of case studies, and the numerical result demonstrates the effectiveness of the suggested solution can optimally operate the BESS with the maximal revenue.

Stimulated by the severe energy crisis and the increasing awareness about the need for environmental protection, the efficient use of renewable energy has become a hot topic. The virtual power plant (VPP) is an effective way of integrating distributed energy systems (DES) by effectively deploying them in power grid dispatching or electricity trading. In this paper, the operating mode of the VPP with penetration of wind power, solar power and energy storage is investigated. Firstly, the grid-connection requirements of VPP according to the current wind and solar photovoltaic (PV) grid-connection requirements, and analyzed its profitability are examined. Secondly, under several typical scenarios grouped by a self-organization map (SOM) clustering algorithm using the VPP’s output data, a profit optimization model is established as a guideline for the VPP’s optimal operation. Based on this model, case studies are performed and the results indicate that this model is both feasible and effective.

In the context of current energy shortage and environmental degradation, the penetration rate of demand-side energy resources (DSER) in the power grid is constantly increasing. To alleviate the problems concerning the energy and environment, it is of tremendous urgency to develop and make effective use of them. Therefore, this paper proposes the evaluation model of DSER in urban power grid based on geographic information, and a variety of demand-side energy resources in a region is evaluated. Firstly, as for five kinds of DSER, revolving wind power generation (WG), photovoltaic power generation (PV), electric vehicle (EV), energy storage (ES), and flexible load, the commonality indexes and individuality indexes of all kinds of resources are selected based on geographic information. The commonality indexes are common indexes of all DSER, and the individuality indexes are unique indexes of all DSER. Then the weight of each subindex under the commonality and individuality indexes are determined by analytic hierarchy process (AHP) and entropy weight method, respectively. Finally, weighted overlay are made according to the weights and quantized values of each index, and a comprehensive score is obtained from the commonality indexes and individuality indexes upon various demand-side energy resources in the region. The result depicts that the proposed evaluation model of demand-side energy resources is of well practicability and effectiveness, which is beneficial to the planning of the city and the power grid. Most of all, such model provides a strong support for the long-term optimization planning and the medium-term optimization aggregation of DSER.

Virtual power plant (VPP) is an effective technology form to aggregate the distributed energy resources (DERs), which include distributed generation (DG), energy storage (ES) and demand response (DR). The establishment of a unified and coordinated control of VPP is an important means to achieve the interconnection of energy internet. Therefore, this paper focuses on the research of VPP construction model. Firstly, a preliminary introduction on all kinds of the DERs is carried out. According to the relevant guidelines, the decision area of the VPP is carefully divided, and the decision variables representing the various resources in the area are determined. Then, in order to get a VPP with low daily average cost, good load characteristics, high degree of DG consumption and high degree of resource aggregation, a multi-objective VPP construction model based on decision area division is established, and various constraints including geographic information are considered. The improved bat algorithm based on priority selection is used to solve this model. Finally, the correctness and effectiveness of the model are verified by an example.

The modular multilevel converter (MMC), as a new type of voltage source converter, is increasingly used because it is a distributed storage system. There are many advantages of using the topological structure of the MMC on a unified power quality controller (UPQC), and voltage sag mitigation is an important use of the MMC energy storage system for the power quality compensation process. In this paper, based on the analysis of the topology of the MMC, the essence of energy conversion in a UPQC of voltage sag compensation is analyzed; then, the energy storage characteristics are calculated and analyzed to determine the performance index of voltage sag compensation; in addition, the simulation method is used to verify the voltage sag compensation characteristics of the UPQC; finally, an industrial prototype of the UPQC based on an MMC for 10 kV of medium voltage distribution network has been developed, and the basic functions of UPQC have been tested.

In active distribution system (ADS), the access of distributed generation (DG) can effectively improve the power supply capacity (PSC). In order to explore the effect of DG on the PSC, the influence of accessed DG on the power supply of ADS has been studied based on generalized sensitivity analysis (SA). On the basis of deriving and obtaining the sensitivity of the evaluation indexes of the PSC to the parameters of connected DG, seeking for the DG access instruction for the purpose of improving the PSC, PSC evaluation model with inserted DG is established based on SA. The change degrees and trends of the PSC and its evaluation indexes caused by the slight increase of DG are calculated rapidly, which provides reference for the planning and operation of ADS. Finally, the feasibility and validity of the proposed theory are validated via IEEE 14-node case study.

To solve the problem of solar abandoning, which is accompanied by the rapid development of photovoltaic (PV) power generation, a demonstration of a photovoltaic-battery energy storage system (PV-BESS) power plant has been constructed in Qinghai province in China. However, it is difficult for the PV-BESS power plant to survive and develop with the current electricity price mechanism and subsidy policy. In this paper, a three-part electricity price mechanism is proposed based on a deep analysis of the construction and operation costs and economic income. The on-grid electricity price is divided into three parts: the capacity price, graded electricity price, and ancillary service price. First, to ensure that the investment of the PV-BESS power plant would achieve the industry benchmark income, the capacity price and benchmark electricity price are calculated using the discounted cash flow method. Then, the graded electricity price is calculated according to the grade of the quality of grid-connected power. Finally, the ancillary service price is calculated based on the graded electricity price and ancillary service compensation. The case studies verify the validity of the three-part electricity price mechanism. The verification shows that the three-part electricity price mechanism can help PV-BESS power plants to obtain good economic returns, which can promote the development of PV-BESS power plants.

A virtual power plant (VPP) is a special virtual unit that integrates various distributed energy resources (DERs) distributed in the generation and consumption sides. The optimal configuration scheme of the VPP needs to break the geographical restrictions to make full use of DERs, considering the uncertainties. First, the components of the DERs and the structure of the VPP are briefly introduced. Next, the cubic exponential smoothing method is adopted to predict the VPP load requirement. Finally, the optimal configuration of the DER capacities inside the VPP is calculated by using portfolio theory and genetic algorithms (GA). The results show that the configuration scheme can optimize the DER capacities considering uncertainties, guaranteeing economic benefits of investors, and fully utilizing the DERs. Therefore, this paper provides a feasible reference for the optimal configuration scheme of the VPP from the perspective of investors.

The differences of leaf characteristics, stomatai structure, photosynthesis, chlorophyll content and antioxidant enzyme activities of four different age old Cinnamomum camphora trees in Hunan were measured, and their physiological and ecological characteristics were studied. The results showed that the leaf characteristics of four different age old Cinnamomum camphora trees were leaf thickness, leaf area, leaf dry weight, leaf volume and leaf tissue density decreased with the increase of tree age; The stomatal structure showed that the stomatal density, stomatal aperture and stomatal size decreased with the increase of tree age; the net photosynthetic rate, transpiration rate and stomatal conductance decreased with the increase of tree age, while the intercellular CO2 concentration increased with the increase of tree age; the activities of SOD and cat decreased with the increase of tree age, while pod increased with the increase of tree age. The research results can provide the basis for judging the aging degree of ancient trees and protecting and rejuvenating, and lay a foundation for the protection and utilization of ancient camphor trees. [ABSTRACT FROM AUTHOR]

[Objectives] This study was conducted to investigate the pharmacokinetic characteristics of arctigenin from water extract of Fructus Arctii in piglets, understand its absorption, distribution, transformation and excretion in piglets, and provide theoretical reference for the development and clinical use of new veterinary drugs. [Methods] Six healthy piglets, weighing (30. 0 ± 5. 0) kg, were selected and administered by gavage with a Fructus Arctii water extract at 1.0 g/kg • bw. Blood was collected from the anterior vena cava at different time points. The concentration of arctigenin in pig plasma was determined by HPLC. The main pharmacokinetic parameters were; absorption half-life (t1/2ka) (0.098 ±0.006) h, distribution half-life (t1/2a) (0.208 ±0.009) h, elimination half-life (t1/2p) (23.816 ±2.151) h, apparent volume of distribution (Vd) (32. 212 ±4. 033) I/kg, apparent volume of distribution (Vd) (32. 212 ±4. 033) I/kg, clearance (CLJ (2.384 ± 1. 589) L/(h • kg), peak time (tmax) (0.251 ±0. 011) h, peak concentration (Cmax) (0.560 ±0.063) [xg/ml, and the area under the curve (AUC) at the time of drug administration (9. 620 ± 0.752) [xg • h/ml. [Results] After oral administration of the water extract powder of Fructus Arctii, arctigenin showed a two-compartment model with absorption in piglets, with the characteristics of fast absorption, wide distribution and slow elimination. Arctigenin might have a hepatoenteral circulation in piglets, and the drug effect could last for a long time. [Conclusions] This study provides a theoretical basis and reference for the development and clinical use of new veterinary drugs. [ABSTRACT FROM AUTHOR]

We presented a low-noise, high-gain photodetector based on the bootstrap structure and the L-C (inductance and capacitance) combination. Electronic characteristics of the photodetector, including electronic noise, gain and frequency response, and dynamic range, were verified through a single-frequency Nd:YVO4 laser at 1064 nm with coherent output. The measured shot noise of 50 µ W laser was 13 dB above the electronic noise at the analysis frequency of 2 MHz, and 10 dB at 3 MHz. And a maximum clearance of 28 dB at 2 MHz was achieved when 1.52 mW laser was illuminated. In addition, the photodetector showed excellent linearities for both DC and AC amplifications in the laser power range between 12.5 µ W and 1.52 mW. [ABSTRACT FROM AUTHOR]