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<jats:p>Choosing suitable solvent is the key technology for the electrochemical performance of energy storage device. Among them, vinylene carbonate (VC), fluoroethylene carbonate (FEC), and ethylene sulfite (ES) are the potential organic electrolyte solvents for lithium/sodium battery. However, the quantitative relation and the specific mechanism of these solvents are currently unclear. In this work, density functional theory (DFT) method is employed to study the lithium/sodium ion solvation in solvents of VC, ES, and FEC. We first find that 4VC-Li<jats:sup>+</jats:sup>, 4VC-Na<jats:sup>+</jats:sup>, 4ES-Li<jats:sup>+</jats:sup>, 4ES-Na<jats:sup>+</jats:sup>, 4FEC-Li<jats:sup>+</jats:sup>, and 4FEC-Na<jats:sup>+</jats:sup> are the maximum thermodynamic stable solvation complexes. Besides, it is indicated that the innermost solvation shells are consisted of 5VC-Li<jats:sup>+</jats:sup>/Na<jats:sup>+</jats:sup>, 5ES-Li<jats:sup>+</jats:sup>/Na<jats:sup>+</jats:sup>, and 5FEC-Li<jats:sup>+</jats:sup>/Na<jats:sup>+</jats:sup>. It is also indicated that the Li<jats:sup>+</jats:sup> solvation complexes are more stable than Na<jats:sup>+</jats:sup> complexes. Moreover, infrared and Raman spectrum analysis indicates that the stretching vibration of O = C peak evidently shifts to high frequency with the Li<jats:sup>+</jats:sup>/Na<jats:sup>+</jats:sup> concentration reducing in <jats:italic>n</jats:italic>VC-Li<jats:sup>+</jats:sup>/Na<jats:sup>+</jats:sup> and <jats:italic>n</jats:italic>FEC-Li<jats:sup>+</jats:sup>/Na<jats:sup>+</jats:sup> solvation complexes, and the O = C vibration peak frequency in Na<jats:sup>+</jats:sup> solvation complexes is higher than that of Li<jats:sup>+</jats:sup> complexes. The S = O stretching vibration in <jats:italic>n</jats:italic>ES-Li<jats:sup>+</jats:sup>/Na<jats:sup>+</jats:sup> solvation complexes moves to high frequency with the decrease of the Li<jats:sup>+</jats:sup>/Na<jats:sup>+</jats:sup> concentration, the S = O vibration in <jats:italic>n</jats:italic>ES-Na<jats:sup>+</jats:sup> is higher than that in <jats:italic>n</jats:italic>ES-Li<jats:sup>+</jats:sup>. The study is meaningful for the design of new-type Li/Na battery electrolytes.</jats:p>

<jats:p>A novel dual direction silicon-controlled rectifier (DDSCR) with an additional P-type doping and gate (APGDDSCR) is proposed and demonstrated. Compared with the conventional low-voltage trigger DDSCR (LVTDDSCR) that has positive and negative holding voltages of 13.371 V and 14.038 V, respectively, the new DDSCR has high positive and negative holding voltages of 18.781 V and 18.912 V in a single finger device, respectively, and it exhibits suitable enough positive and negative holding voltages of 14.60 V and 14.319 V in a four-finger device for ±12-V application. The failure current of APGDDSCR is almost the same as that of LVT-DDSCR in the single finger device, and the four-finger APGDDSCR can achieve positive and negative human-body model (HBM) protection capabilities of 22.281 kV and 23.45 kV, respectively, under 40-V voltage of core circuit failure, benefitting from the additional structure. The new structure can generate a snapback voltage on gate A to increase the current gain of the parasitic PNP in holding voltage. Thus, a sufficiently high holding voltage increased by the structure can ensure that a multi-finger device can also reach a sufficient holding voltage, it is equivalent to solving the non-uniform triggering problem of multi-finger device. The operating mechanism and the gate voltage are both discussed and verified in two-dimensional (2D) simulation and experiemnt.</jats:p>

<jats:p>Strontium titanate (SrTiO<jats:sub>3</jats:sub>), which is a crucial perovskite oxide with a direct energy band gap of 3.2 eV, holds great promise for ultraviolet (UV) photodetection. However, the response performance of the conventional SrTiO<jats:sub>3</jats:sub>-based photodetectors is limited by the large relative dielectric constant of the material, which reduces the internal electric field for electron-hole pair separation to form a current collected by electrodes. Recently, graphene/semiconductor hybrid photodetectors by van-der-Waals heteroepitaxy method demonstrate ultrahigh sensitivity, which is benefit from the interface junction architecture and then prolonged lifetime of photoexcited carriers. Here, a graphene/SrTiO<jats:sub>3</jats:sub> interface-based photodetector is demonstrated with an ultrahigh responsivity of 1.2 × 10<jats:sup>6</jats:sup> A/W at the wavelength of 325 nm and ∼ 2.4 × 10<jats:sup>4</jats:sup> A/W at 261 nm. The corresponding response time is in the order of ∼ ms. Compared with graphene/GaN interface junction-based hybrid photodetectors, ∼ 2 orders of magnitude improvement of the ultrahigh responsivity originates from a gain mechanism which correlates with the large work function difference induced long photo-carrier lifetime as well as the low background carrier density. The performance of high responsivity and fast response speed facilitates SrTiO<jats:sub>3</jats:sub> material for further efforts seeking practical applications.</jats:p>

<jats:p>Molecular dynamics simulation (MDS) is a powerful technology for investigating evolution dynamics of target proteins, and it is used widely in various fields from materials to biology. This mini-review introduced the principles, main preforming procedures, and advances of MDS, as well as its applications on the studies of conformational and allosteric dynamics of proteins especially on that of the mechanosensitive integrins. Future perspectives were also proposed. This review could provide clues in understanding the potentiality of MD simulations in structure–function relationship investigation of biological proteins.</jats:p>

<jats:p>Excitable media, such as cells, can be polarized and magnetized in the presence of an external electromagnetic field. In fact, distinct geometric deformation can be induced by the external electromagnetic field, and also the capacitance of the membrane of cell can be changed to pump the field energy. Furthermore, the distribution of ion concentration inside and outside the cell can also be greatly adjusted. Based on the theory of bio-electromagnetism, the distribution of field energy and intracellular and extracellular ion concentrations in a single shell cell can be estimated in the case with or without external electric field. Also, the dependence of shape of cell on the applied electronic field is calculated. From the viewpoint of physics, the involvement of external electric field will change the gradient distribution of field energy blocked by the membrane. And the intracellular and extracellular ion concentration show a certain difference in generating time-varying membrane potential in the presence of electric field. When a constant electric field is applied to the cell, distinct geometric deformation is induced, and the cell triggers a transition from prolate to spherical and then to oblate ellipsoid shape. It is found that the critical frequency in the applied electric field for triggering the distinct transition from prolate to oblate ellipsoid shape obtains smaller value when larger dielectric constant of the cell membrane and intracellular medium, and smaller conductivity for the intracellular medium are used. Furthermore, the effect of cell deformation is estimated by analyzing the capacitance per unit area, the density of field energy, and the change of ion concentration on one side of cell membrane. The intensity of external applied electric field is further increased to detect the change of ion concentration. And the biophysical effect in the cell is discussed. So the deformation effect of cells in electric field should be considered when regulating and preventing harm to normal neural activities occurs in a nervous system.</jats:p>

<jats:p>This work explores the function of the noisy direct delayed feedback (NDDF) control strategy in suppressing the pathological oscillations in the basal ganglia (BG) with Parkinson’s disease (PD). Deep brain stimulation (DBS) alleviates the PD state fantastically. However, due to its unclear mechanism and open-loop characteristic, it is challenging to further improve its effects with lower energy expenditure. The noise stimulus performs competitively in alleviating the PD state theoretically, but it cannot adapt to the neural condition timely and automatically due to its open-loop control scheme. The direct delayed feedback (DDF) control strategy is able to disturb excessive synchronous effectively. Therefore, the NDDF control strategy is proposed and researched based on a BG computational model, which can reflect the intrinsic properties of the BG neurons and their connections with thalamic neurons. Simulation results show that the NDDF control strategy with optimal parameters is effective in removing the pathological beta oscillations. By comparison, we find the NDDF control strategy performs more excellent than DDF in alleviating PD state. Additionally, we define the multiple-NDDF control strategy and find that the multiple-NDDF with appropriate parameters performs better than NDDF. The obtained results contribute to the cure for PD symptoms by optimizing the noise-induced improvement of the BG dysfunction.</jats:p>

<jats:p>The establishment of effective null models can provide reference networks to accurately describe statistical properties of real-life signed networks. At present, two classical null models of signed networks (i.e., sign and full-edge randomized models) shuffle both positive and negative topologies at the same time, so it is difficult to distinguish the effect on network topology of positive edges, negative edges, and the correlation between them. In this study, we construct three refined edge-randomized null models by only randomizing link relationships without changing positive and negative degree distributions. The results of nontrivial statistical indicators of signed networks, such as average degree connectivity and clustering coefficient, show that the position of positive edges has a stronger effect on positive-edge topology, while the signs of negative edges have a greater influence on negative-edge topology. For some specific statistics (e.g., embeddedness), the results indicate that the proposed null models can more accurately describe real-life networks compared with the two existing ones, which can be selected to facilitate a better understanding of complex structures, functions, and dynamical behaviors on signed networks.</jats:p>

<jats:p>We investigate the Furi–Martelli–Vignoli spectrum and the Feng spectrum of continuous nonlinear block operator matrices, and mainly describe the relationship between the Furi–Martelli–Vignoli spectrum (compared to the Feng spectrum) of the whole operator matrix and that of its entries. In addition, the connection between the Furi–Martelli–Vignoli spectrum of the whole operator matrix and that of its Schur complement is presented by means of Schur decomposition.</jats:p>

<jats:p>High detection efficiency and low intrinsic dark count rate are two advantages of superconducting nanowire single photon detectors (SNSPDs). However, the stray photons penetrated into the fiber would cause the extrinsic dark count rate, owing to the free running mode of SNSPDs. In order to improve the performance of SNSPDs in realistic scenarios, stray photons should be investigated and suppression methods should be adopted. In this study, we demonstrate the pulse-gated mode, with 500 kHz gating frequency, of a commercial SNSPD system for suppressing the response of stray photons about three orders of magnitude than its free-running counterpart on the extreme test conditions. When we push the gating frequency to 8 MHz, the dark count rate still keeps under 4% of free-running mode. In experiments, the intrinsic dark count rate is also suppressed to 4.56 × 10<jats:sup>−2</jats:sup> counts per second with system detection efficiency of 76.4372%. Furthermore, the time-correlated single-photon counting analysis also approves the validity of our mode in suppressing the responses of stray photons.</jats:p>

<jats:p>We use the full-density matrix numerical renormalization group method to calculate the equilibrium dynamical correlation function <jats:italic>C</jats:italic>(<jats:italic>ω</jats:italic>) of the spin operator <jats:italic>σ<jats:sub>z</jats:sub> </jats:italic> at finite temperature for the sub-ohmic spin-boson model. A peak is observed at the frequency <jats:italic>ω</jats:italic> <jats:sub>T</jats:sub> ∼ <jats:italic>T</jats:italic> in the curve of <jats:italic>C</jats:italic>(<jats:italic>ω</jats:italic>). The curve merges with the zero-temperature <jats:italic>C</jats:italic>(<jats:italic>ω</jats:italic>) in <jats:italic>ω</jats:italic> ≫ <jats:italic>ω</jats:italic> <jats:sub>T</jats:sub> and deviates significantly from the zero-temperature curve in <jats:italic>ω</jats:italic> ≪ <jats:italic>ω</jats:italic> <jats:sub>T</jats:sub>.</jats:p>