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Vascular endothelial function and atherosclerosis are known to be important risk factors for cardiovascular disease. However, it remains unknown whether remnant cholesterol (RC) correlates with vascular endothelial function and atherosclerosis as represented by flow-mediated vasodilation (FMD) and brachial-ankle pulse wave velocity (baPWV). Therefore, in this study, we aimed to investigate this in the general population.In this study, we examined 13,237 subjects who have undergone blood lipid, FMD, and baPWV measurements. Participants were divided into four groups based on RC quartiles. Multivariable linear regression models were used to calculate odds ratios for FMD and baPWV according to the RC levels.A significant negative relationship was found between RC and FMD (β=-0.14, p=0.014), whereas RC was positively associated with baPWV (β=21.42, p＜0.001), especially in the male and without chronic disease medication populations. The population was divided into three groups according to their lipids: dyslipidemia group, nondyslipidemia but RC increased group (RC ＞0.78 mmol/L), and nondyslipidemia and RC normal group (RC ≤ 0.78 mmol/L). The FMD of the three groups was 7.09%±3.36%, 7.39%±3.38%, and 7.57%±3.54%, respectively. The baPWV of the three groups was 1445.26±261.56 cm/s, 1425.04±265.24 cm/s, and 1382.73±267.75 cm/s. Significant differences were noted between the groups.The findings indicated that a higher RC was an independent predictive factor for participants with endothelial function and atherosclerosis. It is important to use RC as a risk management indicator of vascular function, especially for those with normal conventional lipid parameters but increased RC.

Recent earthquakes in New Zealand and Japan showed that pre-shaking histories significantly affected the reliquefaction resistance of soils. In this study, a series of experimental tests was conducted to elucidate the coupled effects of inherent and induced anisotropy on reliquefaction resistance of Toyoura sand, which have not been studied before. Accordingly, loose and dense Toyoura sands were prepared with two different methods: dry deposition and moist tamping. The specimens were sheared cyclically using a hollow cylinder torsional shear apparatus under various cyclic stress ratios up to different residual shear strains (γres) and reconsolidated at different states. The experimental results were assessed from various perspectives, including stress–strain relationships, failure mechanisms, liquefaction/reliquefaction resistance, excess pore water pressure (EPWP) generation and compressibility in conjunction with micromechanical interpretations. It was shown that fabric evolution affects the reliquefaction characteristics of Toyoura sand substantially. Interestingly, a unique correlation exists between EPWP and shear strain accumulation for all tests. An energy-based model was developed to uniquely correlate the dissipated energy with the cyclic resistance based only on residual shear strains; this model shows great promise to develop a unified, energy-based criterion for quantifying the liquefaction/reliquefaction resistance of soils with different fabrics.

Automated vehicles with parallel autonomy show advantages over fully automated vehicles and manual driving. This paper proposes a hierarchical motion planning method that mixes inputs of human drivers and the automated driving systems for automated vehicles in scenarios such as multi-lane roads and multi-intersections with dynamic obstacles. The proposed method comprises a reference path generator in the upper level and a nonlinear model predictive controller with mixed human-vehicle control in the lower level. The path planner considers dynamic obstacles, static obstacles, and human comfort to generate a reference path composed of splines with continuous curvatures in the upper level. In the lower level, the MPC generates a trajectory by tracking the reference path and optimizing the cost function containing inputs of drivers while avoiding both dynamic and static obstacles. The simulation verifies the efficacy and the computational tractability of the proposed method.

Background. Excessive proliferation and activation of B cells, resulting in the production of various autoantibodies, is a crucial link and significant feature of the pathogenesis of systemic lupus erythematosus (SLE), as well as the pathological basis of systemic multiorgan damage. However, whether exosomes derived from human umbilical cord mesenchymal stem cells (hucMSCs-Exo) are involved in the immune regulation of SLE has not been clarified. Objectives. Therefore, our study aimed to investigate the efficacy of hucMSCs-Exo for treating SLE. Methods. hucMSCs-Exo and peripheral blood mononuclear cells (PBMCs) of SLE patients were cocultured in vitro, and B cell apoptosis, activation, proliferation, and inflammation levels were detected by flow cytometry. Subsequently, the expression level of miR-155 in B lymphocytes of SLE patients was detected by qRT-PCR, and the target gene relationship between miR-155 and SHIP-1 was found through bioinformatics and dual luciferase activity experiments, which verified the inhibition of miR-155 in B lymphocytes of SLE patients to regulate immunity. Results. We found that hucMSCs-Exo promoted B cell apoptosis, prevented B cell overactivation, and reduced inflammation. MicroRNA-155 (miR-155) has a powerful regulatory function in B cells. It was demonstrated that hucMSCs-Exo acts synergistically with miR-155 inhibitors to target SHIP-1 to B cells more effectively than exosomes alone. Conclusion. Our results provide insight into how hucMSCs-Exo regulates autoimmunity in patients with lupus and suggest targeting miR-155 for autoimmunity while protecting immunity.

Implicit solvent models that reduce solvent degrees of freedom into effective interaction potentials are widely used in the study of soft materials and biophysical systems. For electrolyte and polyelectrolyte solutions, coarse-graining the solvent degrees of freedom into an effective dielectric constant embeds entropic contributions into the temperature dependence of the dielectric constant. Properly accounting for this electrostatic entropy is essential to discern whether a free energy change is enthalpically or entropically driven. We address the entropic origin of electrostatic interactions in a dipolar solvent and provide a clarified physical picture of the solvent dielectric response. We calculate the potential of mean force (PMF) between two oppositely charged ions in a dipolar solvent using molecular dynamics and dipolar self-consistent field theory. We find with both techniques that the PMF is dominated by the entropy gain from the dipole release, owing to the diminished orientational polarization of the solvent. We also find that the relative contribution of the entropy to the free energy change is nonmonotonic with temperature. We expect that our conclusions are applicable to a broad range of problems involving ionic interactions in polar solvents.

Fine calculation of bridge temperature fields is significant for accurately evaluating thermal actions in bridge structures. Determining thermal loads on bridge surfaces caused by solar radiation is the most challenging part of the numerical thermal analysis because the sunlit and shaded areas on bridge surfaces change continuously with the sun’s rotation. Existing methods have low accuracy in determining thermal loads and cannot be applied to complex bridges. This study presents a new method for calculating temperature fields based on the advantages of building information modeling (BIM) technology in solar radiation analysis (SRA) and information sharing. This method starts with obtaining an accurate hourly insolation distribution on bridge surfaces through SRA implemented in a BIM system. Then, a Python script seamlessly maps the insolation information to finite element surfaces as thermal loads. This paper details the new method’s implementation steps and technical details, and a practical application on a concrete box girder demonstrates its applicability and effectiveness. Compared with previous methods, the proposed method has significant advantages, such as a more accurate calculation for solar radiation, a lower technical threshold, a higher degree of automation, less computational time, and easier finite element modeling.

This paper investigates the elliptic localization for moving object problem from time delay (TD) and Doppler frequency shift (DFS) measurements, where the transmitter position and velocity are unknown. The transmitter is not perfectly time syncronized such that unknown offsets exist in the TD and DFS measurements. We propose to jointly estimate the object and transmitter positions and velocities and the offsets. Using the TD and DFS measurements from both the indirect and direct paths between the transmitter and the receivers, we formulate a non-convex weighted least squares (WLS) problem. Local convergence may occur when solving the non-convex WLS problem, implying that good estimate is not guaranteed. Thus, we relax the non-convex WLS problem into a convex semidefinite program by applying semidefinite relaxation (SDR). Moreover, we theoretically show that the performance can be improved by using multiple transmitters as compared to that using single transmitter, although more unknown parameters are introduced. We then extend the proposed SDR method to handle the multiple transmitters case. Finally, the mean square error analysis is provided to show that the proposed WLS method reaches the Cramer-Rao lower bound accuracy under small Gaussian noise condition. Simulation results validate the theoretical analysis and show the superior performance over the existing methods.

In this paper, a framework that combines an M-estimation and information-theoretic-learning (ITL)-based Kalman filter under impulsive noises is presented. The ITL-based methods make the most of the features of the data itself and can improve robustness by choosing an appropriate kernel bandwidth. However, small kernel bandwidths may lead to divergence. Nonetheless, robust-regression methods can improve the robustness from the statistical perspective and are independent of kernel bandwidth. This motivates us to fuse M-estimation-based weighting methods and the ITL-based Kalman filter. The proposed framework inhibits the divergence trend of ITL-based Kalman filters at low kernel bandwidth and improves the performance at large kernel bandwidth. Additionally, we use the unscented Kalman filtering method to extend the proposed algorithm to the nonlinear case. Monte Carlo simulations demonstrate the robustness and effectiveness of the proposed algorithm.

The existence of multiple waves in seismic data has a substantial impact on earthquake imaging, inversion, and interpretation results. As a result, multiples are often suppressed as noise prior to seismic data preattack processing. Currently, there are two primary methods for suppressing multiple reflections in seismic data. One is a filtering technique based on geometric differences in the seismic waves, while the other is based on wave equation methods. The Radon transform, which suppresses multiple reflections, belongs to the class of geometric seismic diffraction filtering techniques. In the process of seismic data processing, it effectively separates multiple reflections from seismic data by utilizing the characteristic differences between primary and multiple reflections, thereby achieving noise attenuation and improving the signal-to-noise ratio of the data. This article primarily investigates the current state of methods for suppressing multiple reflections based on the Radon transform, both domestically and internationally. By introducing various forms and fundamental principles of the Radon transform, this study analyzes and compares the adaptability and pros and cons of each type of Radon transform. The high-precision Radon transform can effectively address the sawtooth phenomenon and energy dispersion issues that arise in the least-squares Radon transform. It also highlights the challenges associated with suppressing multiple reflections in the Radon transform and provides a glimpse into future developments.