Structural Settlement Analysis and Pre-Reinforcement Research by Considering Structure Stiffness

The movement of the ground caused by the excavation of subway tunnels and the sinking of the earth\u27s surface inevitably affect above-ground buildings, with the impact on historical and cultural buildings, which are already in disrepair, being more prominent. In existing research, the impact of the stiffness of a building itself is often neglected when assessing the influence of the displacement of the stratum caused by tunnel excavation on the building. However, as the settlement and deformation of the building are related to the structural characteristics of the building itself, the effect of the building stiffness should not be completely ignored. This study analyzed the case of the national key protected cultural relics (Red House Hotel) located near the tunnel of the Qingdao Metro (Line 3). Based on the factors affecting the stiffness of the building structure, the Peck empirical formula was modified to predict the effect on the building in the stratum. Subsequently, a three-dimensional finite element model was established and force analysis conducted. Considering the results of the finite element analysis, which determined the stress condition of the cultural relic buildings, a reinforcement design was carried out and implemented in the project

Supramolecular Proton Conductors Self-Assembled by Organic Cages

Proton conduction is vital for living systems to execute various physiological activities. The understanding of its mechanism is also essential for the development of state-of-the-art applications, including fuel-cell technology. We herein present a bottom-up strategy, that is, the self-assembly of Cage-1 and -2 with an identical chemical composition but distinct structural features to provide two different supramolecular conductors that are ideal for the mechanistic study. Cage-1 with a larger cavity size and more H-bonding anchors self-assembled into a crystalline phase with more proton hopping pathways formed by H-bonding networks, where the proton conduction proceeded via the Grotthuss mechanism. Small cavity-sized Cage-2 with less H-bonding anchors formed the crystalline phase with loose channels filled with discrete H-bonding clusters, therefore allowing for the translational diffusion of protons, that is, vehicle mechanism. As a result, the former exhibited a proton conductivity of 1.59 × 10–4 S/cm at 303 K under a relative humidity of 48%, approximately 200-fold higher compared to that of the latter. Ab initio molecular dynamics simulations revealed distinct H-bonding dynamics in Cage-1 and -2, which provided further insights into potential proton diffusion mechanisms. This work therefore provides valuable guidelines for the rational design and search of novel proton-conducting materials

Solenoid-free current drive via ECRH in EXL-50 spherical torus plasmas

As a new spherical tokamak (ST) designed to simplify engineering requirements of a possible future fusion power source, the EXL-50 experiment features a low aspect ratio (A) vacuum vessel (VV), encircling a central post assembly containing the toroidal field coil conductors without a central solenoid. Multiple electron cyclotron resonance heating (ECRH) resonances are located within the VV to improve current drive effectiveness. Copious energetic electrons are produced and measured with hard X-ray detectors, carry the bulk of the plasma current ranging from 50kA to 150kA, which is maintained for more than 1s duration. It is observed that over one Ampere current can be maintained per Watt of ECRH power issued from the 28-GHz gyrotrons. The plasma current reaches Ip>80kA for high density (>5e18me-2) discharge with 150kW ECHR heating. An analysis was carried out combining reconstructed multi-fluid equilibrium, guiding-center orbits of energetic electrons, and resonant heating mechanisms. It is verified that in EXL-50 a broadly distributed current of energetic electrons creates smaller closed magnetic-flux surfaces of low aspect ratio that in turn confine the thermal plasma electrons and ions and participate in maintaining the equilibrium force-balance

Identification of an Ionic Mechanism for ERα-Mediated Rapid Excitation in Neurons

The major female ovarian hormone, 17β-estradiol (E2), can alter neuronal excitability within milliseconds to regulate a variety of physiological processes. Estrogen receptor-α (ERα), classically known as a nuclear receptor, exists as a membrane-bound receptor to mediate this rapid action of E2, but the ionic mechanisms remain unclear. Here, we show that a membrane channel protein, chloride intracellular channel protein-1 (Clic1), can physically interact with ERα with a preference to the membrane-bound ERα. Clic1-mediated currents can be enhanced by E2 and reduced by its depletion. In addition, Clic1 currents are required to mediate the E2-induced rapid excitations in multiple brain ERα populations. Further, genetic disruption of Clic1 in hypothalamic ERα neurons blunts the regulations of E2 on female body weight balance. In conclusion, we identified the Clic1 chloride channel as a key mediator for E2-induced rapid neuronal excitation, which may have a broad impact on multiple neurobiological processes regulated by E2

Protocol for a Single-Center Randomized Controlled Trial of Percutaneous Coronary Intervention Via Distal Transradial Access Versus Transradial Access

Background: Although transradial access (TRA) has become the main vascular access for coronary intervention, its high radial artery occlusion rate limits its application in some patients. Studies have shown that compared with TRA, distal transradial access (dTRA) with the snuffbox area or the Hegu acupoint area as the puncture point significantly decreases the incidence of radial artery occlusion. However, no randomized controlled study has confirmed the safety and efficacy of coronary artery intervention via dTRA in China. Methods and analyses: This single-center, prospective, randomized controlled, superiority open-label study will enroll 428 consecutive patients with coronary heart disease undergoing percutaneous coronary intervention as the study population. After preoperative evaluation, the participants will be randomly divided into a study group (dTRA) and control group (TRA) in a 1:1 ratio. The primary endpoint (radial artery occlusion at 24 hours after operation) and secondary endpoint events will be evaluated and recorded. Study registration: This study has been registered in the Chinese Clinical Trial Registry (registration number: ChiCTR2300073902)

Evaluation and Influence of Chinese Enterprises' Financial Efficiency Based on the Malmquist Index

This paper introduces a superefficiency financial efficiency model with undesirable output based on the features that the output of industrial enterprises contains desirable output as well as undesirable output. Furthermore, the Malmquist index model is constructed for financial efficiency dynamic study, and the spatial Durbin model is constructed for evaluation and impact of enterprises. According to the financial data of Chinese enterprises from 2007 to 2019, this paper evaluates the financial efficiency of Chinese interprovincial industrial enterprises dynamically and measures the influence levels of major impacts on the financial efficiency of Chinese interprovincial industrial enterprises quantitatively. As reported by this paper, the conclusions are as follows: (1) In reference to the financial efficiency dynamic study analysis, there is an obvious growth trend in the financial efficiency of Chinese interprovincial industrial enterprises in different years. Based on the horizontal analysis of financial efficiency, there is a relatively large gap in financial efficiency among Chinese interprovincial industrial enterprises. (2) From the separation factors of financial efficiency analysis, the main factor affecting the growth of the financial efficiency of Chinese industrial enterprises is the modification of technology, and the modification of technical efficiency has a minor impact. (3) In accordance with the impacts of enterprise efficiency analysis, several major factors influence the financial efficiency of Chinese industrial enterprises such as major business cost, operating profit, total liabilities, national capital, and the number of R&D personnel

Static Force Analysis of a 3-DOF Robot for Spinal Vertebral Lamina Milling

In order to realize robot-assisted spinal laminectomy surgery and meet the clinical needs of the robot workspace, including accuracy in human–robot collaboration, an asymmetrical 3-DOF spatial translational robot is proposed, which can realize spinal laminectomy in a fixed posture. First, based on the screw theory, the constraint screw system of the robot was established, and the degree of freedom was derived to verify the spatial translational ability of the robot. Then, a kinematic model of the robot was established, and a static force model of the robot was derived based on the kinematic model. The mathematical relationship between the external force and the joint force/torque was obtained, with the quality of all links considered in the model. Finally, we modeled the robot and imported it into ADAMS to obtain the static force simulation results of the 3D model. The force error was approximately 0.001 N and the torque error was approximately 0.0001 N∙m compared with the simulation results of the mathematical model, accounting for 1% of the joint force/torque, which is acceptable. The result also showed the correctness of the mathematical models, and provides a theoretical basis for motion control and human–robot collaboration

Static Force Analysis of a 3-DOF Robot for Spinal Vertebral Lamina Milling

In order to realize robot-assisted spinal laminectomy surgery and meet the clinical needs of the robot workspace, including accuracy in human–robot collaboration, an asymmetrical 3-DOF spatial translational robot is proposed, which can realize spinal laminectomy in a fixed posture. First, based on the screw theory, the constraint screw system of the robot was established, and the degree of freedom was derived to verify the spatial translational ability of the robot. Then, a kinematic model of the robot was established, and a static force model of the robot was derived based on the kinematic model. The mathematical relationship between the external force and the joint force/torque was obtained, with the quality of all links considered in the model. Finally, we modeled the robot and imported it into ADAMS to obtain the static force simulation results of the 3D model. The force error was approximately 0.001 N and the torque error was approximately 0.0001 N∙m compared with the simulation results of the mathematical model, accounting for 1% of the joint force/torque, which is acceptable. The result also showed the correctness of the mathematical models, and provides a theoretical basis for motion control and human–robot collaboration