摘要:
The HIV-1 transactivator protein Tat interacts with the transactivation response element (TAR) at the three-nucleotide UCU bulge to facilitate the recruitment of transcription elongation factor-b (P-TEFb) and induce the transcription of the integrated proviral genome. Therefore, the Tat-TAR interaction, unique to the virus, is a promising target for developing antiviral therapeutics. Currently, there are no FDA-approved drugs against HIV-1 transcription, suggesting the need to develop novel inhibitors that specifically target HIV-1 transcription. We have identified potential candidates that effectively inhibit viral transcription in myeloid and T cells without apparent toxicity. Among these candidates, two molecules showed inhibition of viral protein expression. A molecular docking and simulation approach was used to determine the binding dynamics of these small molecules on TAR RNA in the presence of the P-TEFb complex, which was further validated by a biotinylated RNA pulldown assay. Furthermore, we examined the effect of these molecules on transcription factors, including the SWI/SNF complex (BAF or PBAF), which plays an important role in chromatin remodeling near the transcription start site and hence regulates virus transcription. The top candidates showed significant viral transcription inhibition in primary cells infected with HIV-1 (98.6). Collectively, our study identified potential transcription inhibitors that can potentially complement existing cART drugs to address the current therapeutic gap in current regimens. Additionally, shifting of the TAR RNA loop towards Cyclin T1 upon molecule binding during molecular simulation studies suggested that targeting the TAR loop and Tat-binding UCU bulge together should be an essential feature of TAR-binding molecules/inhibitors to achieve complete viral transcription inhibition.
作者机构:
[Chang, CH; Ho, Chia-An; Chang, Chun-Hao; Yeh, Hung-Chih; Chen, Chao-Yuan; Ho, Chin-Shan] Natl Taiwan Sport Univ, Grad Inst Sports Sci, Taoyuan City, Taiwan.;[Li, Fang] Cent China Normal Univ, Sch Phys Educ, Wuhan, Hubei, Peoples R China.;[Chen, Chao-Yuan] Natl Taipei Univ Business, Sport Off, Taipei City, Taiwan.
通讯机构:
[Chang, CH ] N;Natl Taiwan Sport Univ, Grad Inst Sports Sci, Taoyuan City, Taiwan.
关键词:
Mechanical property;Myometer;Rowing;Symmetry index
摘要:
BACKGROUND: The mechanical properties of muscles, such as changes in muscle tone and stiffness, are related to sports performance and injuries. Rowers are at increased risk of muscle fatigue and injury during high-repetition and heavy-load cyclic muscle actions. In view of this, the aim of the present study was to investigate the acute effect on muscle tone and stiffness, as well as bilateral muscle asymmetry, in high school rowers after a 2000-meter rowing ergometer test. METHODS: Twelve young male rowers (age = 17.1 ± 0.9 years, body weight = 73.5 ± 9.7 kg) were included in the study. The data of muscle tone (frequency) and stiffness of the posterior deltoids (PD), latissimus dorsi (LD), and rectus femoris (RF) (dominant and non-dominant side) before and after a 2000-m rowing ergometer test were collected using a handheld MyotonPRO device. RESULTS: After the rowing ergometer test, the muscle tone of dominant side PD, LD, and RF were significantly increased (p < 0.05). On the other hand, the muscle stiffness of the non-dominant side LD and RF, as well as the dominant side PD, LD, and RF were significantly increased after the rowing ergometer test (p < 0.05). The muscle tone and stiffness results showed that the dominant side PD, LD, and RF were all significantly higher than the non-dominant side after the rowing ergometer test (p < 0.05), where bilateral PD and RF exhibits moderate asymmetry (5% < symmetry index < 10%). CONCLUSIONS: After a high-intensity and high-load 2000-m rowing ergometer test, PD, LD, and RF showed increases in muscle tone and stiffness, as well as changes in the symmetry of bilateral muscle mechanical properties.
作者机构:
[Yang, Xi-Yan] Yangtze Univ, Sch Phys & Optoelect Engn, Jingzhou 434023, Peoples R China.;[Lai, Xiao-Yu; Tan, Wei-Wei; Yang, Xi-Yan] Hubei Univ Educ, Res Ctr Astron, Wuhan 430205, Peoples R China.;[Tan, Wei-Wei] Cent China Normal Univ, Key Lab Quark & Lepton Phys, Minist Educ, Wuhan 430079, Peoples R China.;[Xu, Ren-Xin] Peking Univ, Sch Phys, Beijing 100871, Peoples R China.;[Xu, Ren-Xin] Peking Univ, Kavli Inst Astron & Astrophys, Beijing 100871, Peoples R China.
通讯机构:
[Lai, XY ] H;Hubei Univ Educ, Res Ctr Astron, Wuhan 430205, Peoples R China.
关键词:
dense matter;(stars:) pulsars: general;(stars:) gamma-ray burst: general
摘要:
Strangeon stars, which are proposed to describe the nature of pulsar-like compact stars, have passed various observational tests. The maximum mass of a non-rotating strangeon star could be high, which implies that the remnants of binary strangeon star mergers could even be long-lived massive strangeon stars. We study rigidly rotating strangeon stars in the slowly rotating approximation, using the Lennard-Jones model for the equation of state. Rotation can significantly increase the maximum mass of strangeon stars with unchanged baryon numbers, enlarging the mass-range of long-lived strangeon stars. During spin-down after merger, the decrease of radius of the remnant will lead to the release of gravitational energy. Taking into account the efficiency of converting the gravitational energy luminosity to the observed X-ray luminosity, we find that the gravitational energy could provide an alternative energy source for the plateau emission of X-ray afterglow. The fitting results of X-ray plateau emission of some short gamma-ray bursts suggest that the magnetic dipole field strength of the remnants can be much smaller than that of expected when the plateau emission is powered only by spin-down luminosity of magnetars.
作者机构:
[Yi, Cong; Yi, C; Pu, Shi] Univ Sci & Technol China, Dept Modern Phys, Hefei 230026, Anhui, Peoples R China.;[Wu, Xiang -Yu; Qin, Guang-You] Cent China Normal Univ, Inst Particle Phys, Wuhan 430079, Hubei, Peoples R China.;[Wu, Xiang -Yu; Qin, Guang-You] Cent China Normal Univ, Key Lab Quark & Lepton Phys MOE, Wuhan 430079, Hubei, Peoples R China.;[Yang, Di-Lun] Acad Sinica, Inst Phys, Taipei 11529, Taiwan.;[Gao, Jian-Hua] Shandong Univ, Inst Space Sci, Shandong Prov Key Lab Opt Astron & Solar Terr Envi, Weihai 264209, Shandong, Peoples R China.
通讯机构:
[Yi, C ] U;Univ Sci & Technol China, Dept Modern Phys, Hefei 230026, Anhui, Peoples R China.
摘要:
We investigate the azimuthal angle dependent local hydrodynamic helicity polarization of Λ hyperons, defined as the projection of the spin polarization vector along the directions of particle momenta, at BNL Relativistic Heavy Ion Collider beam energy scan energies by utilizing the relativistic ( 3+1 )D CLVisc hydrodynamics framework with SMASH initial conditions. As opposed to local spin polarization at high energy collisions, our hydrodynamic simulations demonstrate that the azimuthal angle dependent helicity polarization induced by the kinetic vorticity dominates over other contributions at intermediate and low collision energies. Our findings provide an opportunity to probe the fine structure of local kinetic vorticity as a function of azimuthal angle at intermediate and low collision energies by mapping our predictions to the future measurements in experiments.
作者机构:
[Wu, Yanwen; Cao, Shuangshuang; Ma, Yanmei; Ge, Di] Cent China Normal Univ, Sch Phys Sci & Technol, Wuhan 430079, Peoples R China.;[Cheng, Yuhang] Shaanxi GSXZ Technol Co Ltd, Xian 710018, Peoples R China.;[Wu, Yanwen] Cent China Normal Univ, Natl Digital Learning Engn Technol Res Ctr, Wuhan 430079, Peoples R China.
通讯机构:
[Wu, YW ] C;Cent China Normal Univ, Sch Phys Sci & Technol, Wuhan 430079, Peoples R China.;Cent China Normal Univ, Natl Digital Learning Engn Technol Res Ctr, Wuhan 430079, Peoples R China.
关键词:
Anomaly detection;Multivariate time-series;Spatiotemporal;Abnormal information expression;Graph contrastive learning
摘要:
The detection of anomalies in high-dimensional time-series has always played a crucial role in the domain of system security. Recently, with rapid advancements in transformer model and graph neural network (GNN) technologies, spatiotemporal modeling approaches for anomaly detection tasks have been greatly improved. However, most methods focus on optimizing upstream time-series prediction tasks by leveraging joint spatiotemporal features. Through experiments, we found that this modeling approach not only risks the loss of some original anomaly information during data preprocessing, but also focuses on optimizing the performance of the upstream prediction task and does not directly enhance the performance of the downstream detection task. We propose a spatiotemporal anomaly detection model that incorporates an improved attention mechanism in the process of temporal modeling. We adopt a heterogeneous graph contrastive learning approach in spatio modeling to compensate for the representation of anomalous behavioral information, thereby guiding the model through thorough training. Through validation on two widely used real-world datasets, we demonstrate that our model outperforms baseline methods. We also explore the impact of multivariate time-series prediction tasks on the detection task, and visualize the reasons behind the benefits gained by our model.
通讯机构:
[Xue, Q ] C;[Xie, GH ] X;Xiamen Univ, Inst Flexible Elect Future Technol, Xiamen 361005, Peoples R China.;Wuhan Univ, Sauvage Ctr Mol Sci, Dept Chem, Hubei Key Lab Organ & Polymer Optoelect Mat, Wuhan 430072, Peoples R China.;Cent China Normal Univ, Dept Phys Sci & Technol, Wuhan 430079, Peoples R China.
摘要:
Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) is a widely used conductive polymer in organic light-emitting devices. However, its strong acidity and fluorescence quenching effect seriously affect the overall device performance. We report a cost-effective method to address the above concerns by diluting PEDOT:PSS with deionized water, which effectively reduced the film thickness and the acidity. Therefore, the fluorescence quenching occurring at the interface was alleviated. Using the modified PEDOT:PSS as the hole injection layer, the external quantum efficiency of the device could be effectively improved by a factor of 81%, reaching a considerably higher value of 23.5%, compared with the device consisting of the original PEDOT:PSS solution used as received. A cost-effective method to address the issues of strong acidity and exciton quenching of PEDOT:PSS was developed by diluting it with deionized water. The solution-processed organic LEDs achieved almost doubled efficiencies with the modified PEDOT:PSS.
通讯机构:
[Tang, YW ] C;Cent China Normal Univ, Inst Nanosci & Technol, Coll Phys Sci & Technol, Wuhan 430079, Peoples R China.
关键词:
Metal organic framework;Core-shell;Ostwald ripening;Aqueous zinc -ion batteries
摘要:
The nanostructure designing strategy is one of the most effective methods to carry out the optimization of cathode materials for aqueous zinc ion batteries (ARZIBs). The design and synthesis of materials with stable nanostructure and short ion/electron transport paths are expected to alleviate the dilemma faced by vanadiumbased materials, such as poor electrical conductivity and structural changes. Ostwald ripening is a promising option in the design and fabrication of special nanostructures such as hollow and core shells. Selecting vanadiumbased metal-organic frameworks (V-MOF) as reactants, we successfully obtained vanadium oxide precursors with self-growing core-shell structures in one-step. As the reaction time increases, the vanadium oxide precursors undergo the process of microspheres -> core-shell -> yolk shell, which is thought to be the result of Ostwald ripening. After annealing, the vanadium oxide precursor becomes a "core-shell" structure vanadium pentoxide (core-shell V2O5). The ARZIBs assembled with core-shell V2O5 cathodes showed superior capacity (309.4 mAh/g at 0.1 A/g) and cycling stability (91.4 % capacity retention after 4000 cycles at 3A/g). Hence, we successfully realized the self-growth of vanadium oxide with core-shell structure in one step but also revealed the crystallization process based on Ostwald ripening and its zinc storage mechanism, which provides new possibilities for the facile synthesis of special nanostructured ARZIB cathode materials.
关键词:
Energy splitting of STAR-RIS;time switching of STAR-RIS;UAV-enabled outdoor-to-indoor WPCN;indoor NFZ
摘要:
This letter investigates a Simultaneously Transmitting and Reflecting Reconfigurable Intelligent Surface (STAR-RIS)-assisted unmanned aerial vehicle (UAV)-enabled outdoor-to-indoor (O2I) wireless powered communication network (WPCN), in which the UAV avoids flying over the indoor no-fly zone (NFZ). In the downlink energy transfer (DET) stage, the energy-constrained STAR-RIS and the O2I Internet of Things (IoT) devices harvest energy from the radio frequency (RF) signals of the UAV to self-sustain its operation. In the uplink information transmission (UIT) stage, the IoT devices transmit information to the UAV using the harvested energy, assisted by the STAR-RIS. We introduce the STAR-RIS energy splitting (ES) and time switching (TS) operating protocols in the DET and UIT stages, respectively, to maximize the harvested downlink energy and the achievable uplink sum-rate. Further, an alternating optimization (AO) algorithm based on the penalty method and successive convex approximation (SCA) technology is proposed to solve the resulting highly-coupled non-convex optimization problems, in which the UAV trajectory based on the UAV power consumption model, resource allocation of the O2I IoT devices, and beamforming vectors of the STAR-RIS are jointly optimized. Finally, numerical results demonstrate that our proposed scheme can achieve significant system sum-rate gains that are better than other baseline schemes.
摘要:
The observational data (e.g., the timing data and magnetic tilt angles chi) of young pulsars can be used to probe some critical issues about the internal physics of neutron stars (NSs), for instance, the number of precession cycles xi and the internal magnetic field configuration (IMFC) of NSs. Evolution of the dipole magnetic field B-d of NSs may play an important role in determining the final results. In this work, a power-law form is adopted to describe the decay of B-d. In such a scenario, the IMFC and xi of young pulsars with an ordinary B-d similar to 1012-1013 G and a steady braking index n are investigated. Since the tilt angle change rates chi(center dot) of pulsars with n < 3 can be theoretically predicted, a test on the power-law decay model can thus be made by comparing the theoretical values to that obtained from observations. However, such a comparison can only be made on the Crab pulsar currently, and the results show that the power-law decay model is inconsistent with the Crab's observations. We suggest that rather than decay, the Crab's B-d should increase with time at a rate similar to 12-14 G/s. A definite conclusion on the validity of the power-law decay model for pulsars with ordinary B-d may be given if chi(center dot) of other pulsars could be measured.
摘要:
The main goal of this paper is to investigate the predefined-time sliding mode control and synchronization of uncertain hyperchaotic systems and its application in secure communication. Firstly, a novel predefined-time sliding surface is designed. Then a predefined-time sliding mode controller is proposed for uncertain hyperchaotic systems, which can guarantee synchronization of the master-slave system within a predefined time in the presence of parameter uncertain and external disturbance. Specially, the settling time, as a part of control parameters, can be predefined as needed independent of initial conditions. Furthermore, the validity of the proposed approach is proved by Lyapunov stability theory. Finally, comparative tests and image encryption application are given to show advantages of the proposed method.
通讯机构:
[Hu, P ; Yang, Z] H;Hubei Univ Technol, Sch Sci, Wuhan 430068, Peoples R China.
关键词:
aqueous NH4+-ion batteries;one pot synthesis;prussian blue analogues;reversible electrochemical reaction
摘要:
Ammonium‐ion batteries: NH4+‐rich nickel hexacyanoferrate was successfully synthesized through a facile one‐pot method. It exhibits excellent electrochemical performances as cathode material for ammonium‐ion batteries which can be attributed to reversible redox reaction and durable structure. Abstract Rechargeable aqueous batteries based on ammonium‐ion (NH4+) redox reactions shows great potential for large‐scale energy‐storage due to its plentiful supplies, environmental friendliness, intrinsic security, and sustainability. Prussian blue analogues (PBAs) are regarded to be one of the most promising electrode materials owning to high energy storage density, ease of synthesis, and excellent electrochemical performances. However, the synthesis of ammonium rich Prussian blue analogues is too complicated. Herein, a one pot synthesis of NH4+‐rich nickel hexacyanoferrate (NNiHCF) is developed and the NH4+ storage chemistry is investigated. NNiHCF cathode is coupled with an activated carbon (AC) anode and (NH4)2SO4 aqueous electrolyte to assemble ammonium‐ion batteries. The aqueous full cell demonstrates good electrochemical performance, such as 50.2 mAh g−1 at the current rate of 2 C, and 60 % capacity retention in 5000 cycles. Furthermore, the fundamental characteristics of the reversible redox reaction and the durable structure of NNiHCF are revealed by X‐ray diffraction (XRD) and electrochemical measurements. This work proposes a facile method for the synthesis of ammonium‐rich Prussian.
作者机构:
[Chang, Wen-Bin] Cent China Normal Univ, Inst Particle Phys, Wuhan 430079, Peoples R China.;Cent China Normal Univ, Key Lab Quark & Lepton Phys MOS, Wuhan, Peoples R China.
通讯机构:
[Chang, WB ] C;Cent China Normal Univ, Inst Particle Phys, Wuhan 430079, Peoples R China.
摘要:
In this study, we utilize the complexity-action duality to study the evolution of complexity in a holographic QCD model at finite temperature and chemical potential. By inserting a fundamental string as a probe, we investigated the properties of complexity growth in this Einstein-Maxwell-scalar gravity system, which is affected by the string velocity, chemical potential, and temperature. Our results show that the complexity growth is maximized when the probe string is stationary, and it decreases as the velocity of the string increases. When the string approaches relativistic velocities, the complexity growth always increases monotonically with respect to the chemical potential. Furthermore, we find that the complexity growth can be used to identify phase transitions and crossovers in the model.
摘要:
In this paper, we construct a bounce inflation cosmological scenario in the framework of the modified symmetric teleparallel gravity, namely f(Q) theory, and investigate the tensor perturbations therein. As is well-known, the tensor perturbations generated in the very early Universe (inflation and pre-inflation regions) can account for the primordial gravitational waves (PGWs) that are to be detected by the next generation of GW experiments. We discuss the stability condition of the tensor perturbations in the bounce inflation process and investigate in detail the evolution of the perturbation variable. The general form of the tensor power spectrum is obtained both for large as well as small scale modes. As a result, we show both kinds of modes (short or long wavelength modes), and the tensor spectrum may get a positive tilt in the parametric range where the tensor perturbation proves to be stable-this interestingly hints an enhancement of gravitational waves' amplitude in the background of the f(Q) bounce-inflation scenario. Moreover, we study the LQC-like scenario as a specific case of our model, in which, the primordial tensor power spectrum turns out to be nearly scale-invariant on both small and large scales.
作者:
Aaij, R.;Abdelmotteleb, A. S. W.;Beteta, C. Abellan;Abudinen, F.;Ackernley, T.;...
期刊:
Journal of High Energy Physics,2024年(2) ISSN:1029-8479
通讯作者:
Aaij, R
作者机构:
[Ketel, T.; Tuning, N.; Usachov, A.; de Boer, J.; Lukashenko, V.; Galati, M. D.; Heijhoff, K.; Akiba, K.; Aaij, R.; Aaij, R; Snoch, A.; Biolchini, A.; Jans, E.; Greeven, L. M.; Geertsema, R. E.; Pellegrino, A.; Gabriel, E.; Merk, M.; van Veghel, M.; Butter, J. S.; Koppenburg, P.; Soares, M. Senghi; Klaver, S.; Gras, C. Sanchez; Raven, G.; Sole, S. Ferreres; Kostiuk, I.; Schubiger, M.; Hulsbergen, W.] Nikhef Natl Inst Subat Phys, Amsterdam, Netherlands.;[Baptista de Souza Leite, J.; De Freitas Carneiro Da Graca, U.; Massafferri, A.; Cruz Torres, M.; De Miranda, J. M.; Falcao, L. N.; Bediaga, I. B.; Gomes, A.; Torres Machado, D.; dos Reis, A. C.; Santoro, L.] Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil.;[Lopes, J. H.; Polycarpo, E.; Souza De Paula, B.; Souza De Almeida, F. L.; Gandelman, M.; Rangel, M. S.; Ferreira Rodrigues, F.; Hicheur, A.; Otalora Goicochea, J. M.; Gomes, A.; De Paula, L.; Nasteva, I.; Amato, S.; Meyer Garcia, L.] Univ Fed Rio de Janeiro, Rio De Janeiro, Brazil.;[Wang, Z.; Qu, S.; Qin, N.; Ren, Z.; Tou, D. Y.; Wang, J.; Li, A.; Hu, X.; Song, Y.; Tan, Y.; Gong, G.; Lian, Z.; Kang, Y.; Qi, H. R.; Zhu, X.; Luo, Y.; Yang, D.; Mu, H.; Zeng, M.; Dong, C.; Zhang, L.] Tsinghua Univ, Ctr High Energy Phys, Beijing, Peoples R China.;[Lu, Y.; Li, Y.; Yuan, X.; Sheng, S.; Li, T.; Wang, J.; Chen, S.; Xu, Z.; Tobin, M.; Miao, D.; Jiang, X.; Batsukh, B.; Zou, Q.; Feng, M.; Liu, S.; Xiang, Z.] Inst High Energy Phys IHEP, Beijing, Peoples R China.
摘要:
The first measurement of the Z boson production cross-section at centre-of-mass energy v s = 5.02TeV in the forward region is reported, using pp collision data collected by the LHCb experiment in year 2017, corresponding to an integrated luminosity of 100 +/- 2 pb-1. The production cross-section is measured for final-state muons in the pseudorapidity range 2.0 <. < 4.5 with transverse momentum pT > 20 GeV/c. The integrated cross-section is determined to be sZ.mu+mu- = 39.6 +/- 0.7(stat) +/- 0.6(syst) +/- 0.8(lumi) pb for the di-muon invariant mass in the range 60 < M mu mu < 120 GeV/c2. This result and the differential cross-section results are in good agreement with theoretical predictions at next-to-next-to-leading order in the strong coupling constant. Based on a previous LHCb measurement of the Z boson production cross-section in pPb collisions at v sNN = 5.02TeV, the nuclear modification factor RpPb is measured for the first time at this energy. The measured values are 1.2+0.5 -0.3(stat) +/- 0.1(syst) in the forward region (1.53 < y* mu < 4.03) and 3.6+1.6 -0.9(stat)+/- 0.2(syst) in the backward region (-4.97 < y* mu < -2.47), where y* mu represents the muon rapidity in the centre-of-mass frame.
摘要:
Due to its controllable maneuverability, wide coverage, and low cost, unmanned aerial vehicle (UAV) has great potential in post-disaster rescue, cargo transport and emergency communication. Considering its limited onboard energy, energy -efficient UAV communication is a challenge. This research examines the security of simultaneous wireless information and power transfer (SWIPT) systems assisted by intelligent reflecting surfaces (IRS) and UAVs while considering the flight energy of rotary-wing UAVs. Specifically, an IRS is mounted on a UAV to enhance the quality of legitimate transmission, and artificial noise (AN) is introduced into the base station (BS) to reduce eavesdropping quality. The power splitting (PS) technology is adopted at ground devices (GDs) to simultaneously decode information and harvest energy. First, we jointly design the BS transmit beamforming, UAV-IRS phase shifts and trajectory/velocity as well as GDs PS ratio with the aim of maximizing the sum secrecy rate of all GDs. Then, an iterative algorithm is developed to address the formulated problem. In particular, additional variables are introduced to handle this complicated objective function, and the original problem is decoupled into multiple sub-problems, which can be solved alternately by invoking the successive convex approximation (SCA) and semidefinite relaxation (SDR) techniques. Finally, numerical results demonstrate that the proposed scheme exhibits a substantial performance in the security rate of SWIPT systems assisted by UAV-IRS, and its performance is improved by at least 12% compared to benchmark schemes at the flight energy budget e(thr) = 5KJ and the number of reflecting elements N-r = 25.
期刊:
Microwave and Optical Technology Letters,2024年66(1):e33954- ISSN:0895-2477
通讯作者:
Jin, J
作者机构:
[Ma, Li; Liu, Wei] Tianjin Univ, Sch Microelect, Tianjin, Peoples R China.;[Zhang, Qi-Jun] Carleton Univ, Dept Elect, Ottawa, ON, Canada.;[Jin, Jing] Cent China Normal Univ, Coll Phys Sci & Technol, Wuhan, Peoples R China.;[Zhang, Jianan] Southeast Univ, State Key Lab Millimeter Waves, Nanjing, Peoples R China.
通讯机构:
[Jin, J ] C;Cent China Normal Univ, Coll Phys Sci & Technol, Wuhan, Peoples R China.
关键词:
electromagnetic;finite element method;Padé via Arnoldi;single-size simplification
摘要:
Abstract This paper proposes a new Padé via Arnoldi algorithm with single‐size matrix simplification for electromagnetic (EM) fast frequency sweep. New equations are derived to reduce the double‐size system matrix to single‐size system matrix. We also propose a systematic algorithm to calculate S‐parameters using the simplified single‐size system matrix. Using the proposed algorithm, the EM responses can be obtained with the same accuracy while consuming much less time compared with that using the existing double‐size matrix Padé via Lanczos. The proposed algorithm is demonstrated by two microwave examples.
摘要:
This paper proposes a bifunctional linear-to linear polarization converter with a sandwich structure that enables transmissive and reflective polarization conversions in different operating bands, simultaneously. The unit cell of the converter metasurface comprises an S-shaped wire, a dielectric slab, and an S-shaped slot, where the S-shaped wire and slot have complementary structures and a 30 degrees difference in orientation. When an x-polarized electromagnetic wave is incident on the proposed metasurface, most of the transmitted wave is y-polarized in the frequency range of 7.07 GHz to 7.46 GHz, while most of the reflected wave is y-polarized in the frequency range of 16.59 GHz to 16.91 GHz. The physical mechanism underlying these two types of polarization conversions was analyzed based on the surface current, and electric field distributions. Notably, the transmissive polarization conversion was primarily attributed to magnetic resonance, while its reflective counterpart was ascribed to electric resonance. In addition, the Jones vector and Stokes parameters were analyzed thereby elucidating the polarization characteristics of the proposed metasurface. Furthermore, simulation data demonstrated excellent agreement with the measured results of polarization conversion. The designed metasurface will promote subsequent research on bifunctional polarization converters.
摘要:
Stochastic resonance and energy consumption are significant for information processing and transmission in the neural system. In this paper, we constructed an excitatory–inhibitory cortical neuronal network to investigate the response of the system to weak signals and the corresponding energy consumption. The findings indicate that the excitability of neurons modulates the performance of signal response. Furthermore, the performance of signal response exhibits a bell-shaped dependence on ion channel noise, which is a typical manifestation of the stochastic resonance phenomenon. Stochastic resonance also exists in the network with increasing noise at different excitatory coupling strengths and inhibitory coupling strengths. Furthermore, it is found that the neuronal system obtains optimal transmission of the weak signal at a lower energy consumption. It illustrates that there is a certain economy and efficiency in the signal transmission. At weak inhibitory coupling strength, an optimal excitatory coupling strength exists to allow the neuronal network to make the optimal transmission of the weak signal. However, the phenomenon of double resonant peaks occurs at strong inhibitory coupling strength, which is due to the balance of excitatory and inhibitory synaptic currents. Finally, we demonstrated the robustness of the results to network topology and initial conditions. The results of this paper may contribute to the understanding of signal transmission and its energy consumption in cortical networks.
期刊:
Journal of Materials Chemistry C,2024年 ISSN:2050-7526
通讯作者:
Tang, YW;Shi, Y
作者机构:
[Chen, Mingyue; Tang, Yiwen; Ran, Hongbing; Wu, Tong; Tang, YW] Cent China Normal Univ, Coll Phys Sci & Technol, Wuhan 430079, Peoples R China.;[Chen, Junfeng; Shi, Y; Shi, Yun; Zheng, Jiaqian; Li, Xiang] Chinese Acad Sci, Shanghai Inst Ceram, Shanghai 201899, Peoples R China.;[Chen, Junfeng; Shi, Y; Shi, Yun] Univ Chinese Acad Sci, Ctr Mat Sci & Optoelect Engn, Beijing 100049, Peoples R China.;[Wu, Haodi] Huazhong Univ Sci & Technol, WNLO, Wuhan 430074, Peoples R China.;[Wu, Haodi] Huazhong Univ Sci & Technol, Sch Opt & Elect Informat, Wuhan 430074, Peoples R China.
通讯机构:
[Shi, Y ; Tang, YW ] C;Cent China Normal Univ, Coll Phys Sci & Technol, Wuhan 430079, Peoples R China.;Chinese Acad Sci, Shanghai Inst Ceram, Shanghai 201899, Peoples R China.;Univ Chinese Acad Sci, Ctr Mat Sci & Optoelect Engn, Beijing 100049, Peoples R China.
摘要:
Ternary copper halides, such as Cs3Cu2I5, as an emerging class of nontoxic alternatives to lead halide perovskites, have drawn extensive attention in the X-ray detection field due to their efficient self-trapped exciton emissions. However, the light yield far below the theoretical limit seriously hinders the high-resolution X-ray detection application of copper halide scintillators. Herein, Cs3Cu2I5:K+ scintillation films and single crystals with enhanced photoluminescence (PL) and radiation luminescence (RL) were first obtained by adjusting the doping concentration of K+ ions in the 0-8 at% range. The substitution of Cs+ by doping K+ compacted the adjacent [Cu2I5](3-) dimer groups, resulting in a stronger exciton-photon coupling strength. Therefore, Cs3Cu2I5:K+ single crystals exhibited a stronger RL emission under X-ray excitation, and their light output was about 49.6% higher than that of the pure Cs3Cu2I5, with an accelerated scintillation decay time (330 to 241 ns). Benefiting from these advantages, X-ray detectors based on hydrophobic polymethyl methacrylate (PMMA)-coated Cs3Cu2I5:K+ flexible films could deliver a higher X-ray imaging resolution of 11.7 lp mm(-1)@MTF = 0.2 in comparison with the commercial gadolinium oxysulfide (GOS)-based detectors (6.2 lp mm(-1)@MTF = 0.2). This work provides insights for the design of metal halides for use in low-cost and high-resolution flexible X-ray imaging systems.
期刊:
Physica A-Statistical Mechanics and its Applications,2024年637:129533 ISSN:0378-4371
通讯作者:
Liu, FY
作者机构:
[Yang, Chunbin; Liu, Feiyi; Deng, Weibing; Li, Wei; Chen, Xiangna; Liu, FY] Cent China Normal Univ, Key Lab Quark & Lepton Phys MOE, Wuhan 430079, Peoples R China.;[Liu, Feiyi; Deng, Weibing; Li, Wei; Liu, FY] Cent China Normal Univ, Inst Particle Phys, Wuhan 430079, Peoples R China.;[Liu, Feiyi; Papp, Gabor; Liu, FY] Eotv Lorand Univ, Inst Phys, 1-A Pazmany P Setany, H-1117 Budapest, Hungary.;[Chen, Shiyang] Baoshan Univ, Sch Engn & Technol, Baoshan 678000, Peoples R China.;[Shen, Jianmin] Max Planck Inst Math Sci, D-04103 Leipzig, Germany.
通讯机构:
[Liu, FY ] C;Cent China Normal Univ, Key Lab Quark & Lepton Phys MOE, Wuhan 430079, Peoples R China.;Cent China Normal Univ, Inst Particle Phys, Wuhan 430079, Peoples R China.;Eotv Lorand Univ, Inst Phys, 1-A Pazmany P Setany, H-1117 Budapest, Hungary.
摘要:
Machine learning techniques exhibit significant performance in discriminating different phases of matter and provide a new avenue for studying phase transitions. We investigate the phase transitions of three dimensional q -state Potts model on cubic lattice by using a transfer learning approach, Domain Adversarial Neural Network (DANN). With the unique neural network architecture, it could evaluate the high -temperature (disordered) and low -temperature (ordered) phases, and identify the first and second order phase transitions. Meanwhile, by training the DANN with a few labeled configurations, the critical points for q = 2, 3, 4 and 5 can be predicted with high accuracy, which are consistent with those of the Monte Carlo simulations. These findings would promote us to learn and explore the properties of phase transitions in high -dimensional systems.