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A study was conducted to determine the effects of recombinant human immunodeficiency virus (HIV-1) nucleocapsid (NC) protein on the activity and processivity of HIV-1 reverse transcriptase (RT). RT and NC are involved in the complex process by which HIV-1 RNA is converted into viral DNA. The results show that NC affects RT processivity by acting like a single-strand binding accessory protein during HIV-1 DNA synthesis.

Highlights • Coupled axial tension-flexure tests were conducted on RC slender walls. • Axial tensile force levels influence failure modes of RC slender walls. • Axial tensile forces decrease effective flexural stiffness and strength of walls. • Design equations of flexure strength and stiffness of tensile RC walls are estimated. • The proposed refined model accurately estimates axial elongation of RC walls. Abstract Reinforced concrete (RC) walls in high-rise buildings, in particular wall piers that form part of a coupled or core wall system, may experience coupled axial tension-flexure loading when subjected to lateral demands. The seismic behavior of RC walls with various axial tensile forces was investigated by quasi-static tests on four RC slender walls subjected to the combined tension and flexure loading. The failure modes, strength and deformation capacity, effective flexural stiffness, and design equations are presented. The failure modes included flexural-sliding failure and flexural failure. The effective flexural stiffness and lateral strength of the walls significantly decreased as the axial tensile forces were increased. The ACI 318-14 and ASCE/SEI 41-13 code provisions overestimated the effective flexural stiffness of RC walls subjected to axial tension. Although equations proposed by Paulay & Priestley and Adebar et al. consider the influence of axial forces, they were not able to accurately predict the effective flexural stiffness of the RC wall specimens subjected to tensile forces. Both sectional analysis using XTRACT and JGJ 3-2010 (China) code equations provided accurate estimation of the flexural yield strength of walls. Finally, both a refined model and simplified equation were proposed to estimate the axial elongation for RC slender walls subjected to axial tensile force and cyclic lateral loading. [ABSTRACT FROM AUTHOR]

In this paper, secrecy performance of a cognitive two-way denoise-and-forward relaying network consisting of two primary user (PT and PD) nodes, two secondary source (SA and SB) nodes, multiple secondary relay (SRi) nodes and an eavesdropper (E) node is considered, where SA and SB exchange their messages with the help of one of the relays using a two-way relaying scheme. The eavesdropper tries to wiretap the information transmitted between SA and SB. To improve secrecy performance of the network, two relay selection schemes called maximum sum rate and maximum secrecy capacity based relay selection (MSRRS and MSCRS) are proposed and analyzed in terms of intercept probability. It is proved that the MSRRS and MSCRS schemes have the same secrecy performance. Two parameters called average number gain and average cost gain are proposed to show the performance of the proposed relay selection schemes. Numerical results demonstrated that with 10 relay nodes, the proposed relay selection schemes can achieve, respectively, 3.7 dB and 1.9 dB’s improvements in terms of the reduced intercept probability and the enhanced secrecy capacity compared to the traditional round-robin scheme. [ABSTRACT FROM AUTHOR]

• A novel model is proposed to represent a core wall equipped with TVMD outriggers. • The TVMD outrigger system effectively controls drift and acceleration responses. • Control effect of TVMD outrigger system is compared with other types of systems. • Seismic control mechanism is illustrated by energy analysis and modal decomposition. • Multiple TVMD outriggers achieve effective control with reduced demand of parameters. This paper presents research on the seismic response control of core wall structures through the installation of innovative damped outriggers known as tuned viscous mass damper (TVMD) outriggers. In this novel system, the TVMDs are arranged vertically between the outrigger trusses/beams and perimeter columns. A simplified model based on the distributed-parameter system was developed to represent a core wall structure equipped with TVMD outriggers. The dynamic properties and seismic responses of high-rise buildings were calculated through a dynamic analysis of the simplified model in MATLAB. The results indicate that TVMD outriggers designed by using fixed-point theory not only suppress the dynamic responses for the target tuning mode, but also supplement additional damping to lower-order modes. When tuned to the second mode, TVMD outriggers with a mass ratio of 0.1 reduce the maximum inter-story drift and floor acceleration responses by 23.48% and 35.80%, respectively. In addition, the control advantages of TVMD outriggers were demonstrated through energy dissipation analysis and damper force decomposition. The vibration control performance of multiple TVMD outriggers was also investigated and was found to achieve superior seismic control with a significantly reduced demand on the TVMD parameters. [ABSTRACT FROM AUTHOR]

Although graphitic carbon nitride (g-C 3 N 4) is frequently mentioned as an environmentally friendly and low-cost photocatalyst, its photocatalytic efficiency is severely constrained by its greater band gap and easy recombination of photogenerated carriers. Introducing nitrogen defects into the photocatalyst can effectively improve the photocatalytic efficiency of g-C 3 N 4. As the position and concentration of inserted nitrogen defects are important factors affecting the catalytic performance of g-C 3 N 4 , this review summarized the synthesis methods developed in recent years based on the perspective of the regulation of nitrogen defect position and concentration. Additionally, this study provided an overview of the characterization methods for discovering nitrogen defects and accurately identifying their exact positions in g-C 3 N 4. At the same time, the mechanism of nitrogen defects promoting the photocatalytic performance of g-C 3 N 4 was explored from aspects such as enhancing light absorption, promoting the transfer and separation of photogenerated carriers, and increasing the consumption of photogenerated carriers through surface reactions. Finally, the opportunities and challenges of nitrogen defects in identification, synthesis, and mechanism of action were discussed. [Display omitted] • Characterization for identify and location judgment of nitrogen defects in g-C 3 N 4. • Regulation of the location and concentration of nitrogen defects in g-C 3 N 4. • Regulation of energy band structure by different nitrogen defect sites. • Mechanism of charge transfer driven by nitrogen defects in g-C 3 N 4. • Electron aggregation and migration near nitrogen defect increase g-C 3 N 4 reactivity. [ABSTRACT FROM AUTHOR]