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<jats:p>Using density functional theory, we study the alloying of the buckled hexagonal germanene superlattice supported on Al (111)-(3 × 3), the sheet composed of triangular, rhombic, and pentagonal motifs on Al (111)-(3 × 3), and the buckled geometry on Al (111)-(<jats:inline-formula> <jats:tex-math><?CDATA $\sqrt{7}\times \sqrt{7}$?></jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mrow> <mml:msqrt> <mml:mn>7</mml:mn> </mml:msqrt> <mml:mo>×</mml:mo> <mml:msqrt> <mml:mn>7</mml:mn> </mml:msqrt> </mml:mrow> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="cpb_29_10_108103_ieqn1.gif" xlink:type="simple" /> </jats:inline-formula>)(19°), which are denoted, respectively, by BHS, TRP, and SRT7, to facilitate the discussion in this paper. They could be alloyed in the low doping concentration range. The stable configurations BHS, TRP, and SRT7 of the pure and alloyed germanenes supported on both Al (111) and its Al<jats:sub>2</jats:sub>Ge surface alloy, except the SRT7 pure germanene on Al<jats:sub>2</jats:sub>Ge, could re-produce the experimental scanning tunneling microscopy images. The relatively stable Al–Ge alloy species are the Al<jats:sub>3</jats:sub>Ge<jats:sub>5</jats:sub> BHS-2T, Al<jats:sub>3</jats:sub>Ge<jats:sub>5</jats:sub> TRP-2T, and Al<jats:sub>3</jats:sub>Ge<jats:sub>3</jats:sub> SRT7-1T on Al (111) while they are the Al<jats:sub>4</jats:sub>Ge<jats:sub>4</jats:sub> BHS-1T, Al<jats:sub>3</jats:sub>Ge<jats:sub>5</jats:sub> TRP-2T, and Al<jats:sub>27</jats:sub>Ge<jats:sub>27</jats:sub> SRT7-(3 × 3)-9T on Al<jats:sub>2</jats:sub>Ge (the <jats:italic>n</jats:italic> in the <jats:italic>n</jats:italic>T means that there are <jats:italic>n</jats:italic> Ge atoms per unit which sit at the top sites and protrude upward). In addition, the Al<jats:sub>3</jats:sub>Ge<jats:sub>5</jats:sub> BHS-2T and Al<jats:sub>4</jats:sub>Ge<jats:sub>4</jats:sub> BHS-1T are the most stable alloy sheets on Al (111) and Al<jats:sub>2</jats:sub>Ge, respectively. Comparing with the experimental studies, there exists no structural transition among these alloyed configurations, which suggests that the experimental conditions play a crucial role in selectively growing the pure or the alloyed germanene sheets, which may also help grow the one-atomic thick honeycomb structure on idea Al (111).</jats:p>

<jats:p>A new method is presented to generate two-directional (2D) grid multi-scroll chaotic attractors via a specific form of the sine function and sign function series, which are applied to increase saddle points of index 2. The scroll number in the <jats:italic>x</jats:italic>-direction is modified easily through changing the thresholds of the specific form of the sine function, while the scroll number in the <jats:italic>y</jats:italic>-direction is controlled by the sign function series. Some basic dynamical properties, such as equilibrium points, bifurcation diagram, phase portraits, and Lyapunov exponents spectrum are studied. Furthermore, the electronic circuit of the system is designed and its simulation results are given by Multisim 10.</jats:p>

<jats:p>The solar cell based on organic-inorganic hybrid halide perovskite is progressing amazingly fast in last decade owing to the robust experimental and theoretical investigations. First-principles calculation is one of the crucial ways to understand the nature of the materials and is practically helpful to the development and application of perovskite solar cells. Here, we briefly review the progress of theoretical studies we made in the last few years on the modification of electronic structures of perovskites by varying the composition, configuration, and structure, and the new understandings into the defect properties of halide perovskites for solar cell and optoelectronic applications. These understandings are foundations and new starting points for future investigations. We hope the experience and inspiration gained from these studies encourage more theoretical explorations for new functional perovskite-based materials.</jats:p>

<jats:p>A new dual directional silicon-controlled rectifier based electrostatic discharge (ESD) protection device suitable for 12-V applications is proposed in this paper. The proposed device (NPEMDDSCR) is based on the embedded DDSCR (EMDDSCR) structure, in which the P+ electrode and P+ injection are removed from the inner finger. Compared with the conventional modified DDSCR (MDDSCR), its high holding voltage meets the requirements for applications. Compared with the embedded DDSCR (EMDDSCR), it has good conduction uniformity. The MDDSCR, EMDDSCR, and NPEMDDSCR are fabricated with an identical width in a 0.5-μm CDMOS process. In order to verify and predict the characteristics of the proposed ESD protection device, a transmission line pulse (TLP) testing system and a two-dimensional device simulation platform are used in this work. The measurements demonstrate that the NPEMDDSCR provides improved reliability and higher area efficiency for 12 V or similar applications. The measurement results also show that the NPEMDDSCR provides higher robustness and better latch-up immunity capability.</jats:p>

<jats:p>The tunnel field-effect transistor (TFET) is proposed by using the advantages of dopingless and line-tunneling technology. The line tunneling is created due to the fact that the gate electric field is aligned with the tunneling direction, which dramatically enhances tunneling area and tunneling current. Moreover, the effects of the structure parameters such as the length between top gate and source electrode, the length between top gate and drain electrode, the distance between bottom gate and drain electrode, and the metal position on the on-state current, electric field and energy band are investigated and optimized. In addition, analog/radio-frequency performance and linearity characteristics are studied. All results demonstrate that the proposed device not only enhances the on/of current ratio and reduces the subthreshold swing, but also offers eight times improvement in cut-off frequency and gain band product as compared with the conventional point tunneling dopingless TFET, at the same time; it shows better linearity and small distortions. This proposed device greatly enhances the potential of applications in dopingless TFET.</jats:p>

<jats:p>Single event effects (SEEs) in a 28-nm system-on-chip (SoC) were assessed using heavy ion irradiations, and susceptibilities in different processor configurations with data accessing patterns were investigated. The patterns included the sole processor (SP) and asymmetric multiprocessing (AMP) patterns with static and dynamic data accessing. Single event upset (SEU) cross sections in static accessing can be more than twice as high as those of the dynamic accessing, and processor configuration pattern is not a critical factor for the SEU cross sections. Cross section interval of upset events was evaluated and the soft error rates in aerospace environment were predicted for the SoC. The tests also indicated that ultra-high linear energy transfer (LET) particle can cause exception currents in the 28-nm SoC, and some even are lower than the normal case.</jats:p>

<jats:p>Quorum sensing (QS) refers to the cell communication through signaling molecules that regulate many important biological functions of bacteria by monitoring their population density. Although a wide spectrum of studies on the QS system mechanisms have been carried out in experiments, mathematical modeling to explore the QS system has become a powerful approach as well. In this paper, we review the research progress of network modeling in bacterial QS to capture the system’s underlying mechanisms. There are four types of QS system models for bacteria: the Gram-negative QS system model, the Gram-positive QS system model, the model for both Gram-negative and Gram-positive QS system, and the synthetic QS system model. These QS system models are mostly described by the ordinary differential equations (ODE) or partial differential equations (PDE) to study the changes of signaling molecule dynamics in time and space and the cell population density variations. Besides the deterministic simulations, the stochastic modeling approaches have also been introduced to discuss the noise effects on kinetics in QS systems. Taken together, these current modeling efforts advance our understanding of the QS system by providing systematic and quantitative dynamics description, which can hardly be obtained in experiments.</jats:p>

<jats:p>RNAs carry out diverse biological functions, partly because different conformations of the same RNA sequence can play different roles in cellular activities. To fully understand the biological functions of RNAs requires a conceptual framework to investigate the folding kinetics of RNA molecules, instead of native structures alone. Over the past several decades, many experimental and theoretical methods have been developed to address RNA folding. The helix-based RNA folding theory is the one which uses helices as building blocks, to calculate folding kinetics of secondary structures with pseudoknots of long RNA in two different folding scenarios. Here, we will briefly review the helix-based RNA folding theory and its application in exploring regulation mechanisms of several riboswitches and self-cleavage activities of the hepatitis delta virus (HDV) ribozyme.</jats:p>

<jats:p>RNAs play crucial and versatile roles in biological processes. Computational prediction approaches can help to understand RNA structures and their stabilizing factors, thus providing information on their functions, and facilitating the design of new RNAs. Machine learning (ML) techniques have made tremendous progress in many fields in the past few years. Although their usage in protein-related fields has a long history, the use of ML methods in predicting RNA tertiary structures is new and rare. Here, we review the recent advances of using ML methods on RNA structure predictions and discuss the advantages and limitation, the difficulties and potentials of these approaches when applied in the field.</jats:p>