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Preplaced aggregate concrete (PAC) has up to 60 % aggregate volume content, making mesoscale modelling difficult. A novel mesoscale simulation method based on physics engine was proposed in this study to accurately simulate the coarse aggregate skeleton of PAC. Unlike in conventional mesoscale simulations, point-to-point contacts between aggregates were formed due to virtual gravity in the physics engine. To verify this novel method, mechanical property and shrinkage behavior tests of PAC were conducted under different aggregate gradings and with different expansive agents. For the mechanical property test, the simulation results were compared with the test results in terms of the aggregate stacking state, failure mode, stress–strain curve, and mechanical property parameters. Repeatability and aggregate shape analyses were performed using finite element (FE) model. A similar comparison between the simulation and test results was also performed for the shrinkage behavior. A shrinkage coefficient reflecting the relationship between grout and PAC shrinkage was proposed. This novel mesoscale simulation method based on physics engine is particularly suitable for PAC. However, it is not limited to PAC and can be applied to the simulation of conventional concrete, thus solving the problem of traditional simulation methods that struggle to achieve a high aggregate fraction.

Abstract Emerging reconfigurable metasurfaces offer various possibilities for programmatically manipulating electromagnetic waves across spatial, spectral, and temporal domains, showcasing great potential for enhancing terahertz applications. However, they are hindered by limited tunability, particularly evident in relatively small phase tuning over 270°, due to the design constraints with time‐intensive forward design methodologies. Here, a multi‐bit programmable metasurface is demonstrated capable of terahertz beam steering facilitated by a developed physics‐informed inverse design (PIID) approach. Through integrating a modified coupled mode theory (MCMT) into residual neural networks, the PIID algorithm not only significantly increases the design accuracy compared to conventional neural networks but also elucidates the intricate physical relations between the geometry and the modes. Without decreasing the reflection intensity, the method achieves the enhanced phase tuning as large as 300°. Additionally, the inverse‐designed programmable beam steering metasurface is experimentally validated, which is adaptable across 1‐bit, 2‐bit, and tri‐state coding schemes, yielding a deflection angle up to 68° and broadened steering coverage. The demonstration provides a promising pathway for rapidly exploring advanced metasurface devices, with potentially great impact on communication and imaging technologies.

Abstract Background Recent research suggests that periodontitis can increase the risk of chronic obstructive pulmonary disease (COPD). In this study, we performed two-sample Mendelian randomization (MR) and investigated the causal effect of periodontitis (PD) on the genetic prediction of COPD. The study aimed to estimate how exposures affected outcomes. Methods Published data from the Gene-Lifestyle Interaction in the Dental Endpoints (GLIDE) Consortium’s genome-wide association studies (GWAS) for periodontitis (17,353 cases and 28,210 controls) and COPD (16,488 cases and 169,688 controls) from European ancestry were utilized. This study employed a two-sample MR analysis approach and applied several complementary methods, including weighted median, inverse variance weighted (IVW), and MR-Egger regression. Multivariable Mendelian randomization (MVMR) analysis was further conducted to mitigate the influence of smoking on COPD. Results We chose five single-nucleotide polymorphisms (SNPs) as instrumental variables for periodontitis. A strong genetically predicted causal link between periodontitis and COPD, that is, periodontitis as an independent risk factor for COPD was detected. PD (OR = 1.102951, 95% CI: 1.005–1.211, p = 0.039) MR-Egger regression and weighted median analysis results were coincident with those of the IVW method. According to the sensitivity analysis, horizontal pleiotropy’s effect on causal estimations seemed unlikely. However, reverse MR analysis revealed no significant genetic causal association between COPD and periodontitis. IVW (OR = 1.048 > 1, 95%CI: 0.973–1.128, p = 0.2082) MR Egger (OR = 0.826, 95%CI:0.658–1.037, p = 0.1104) and weighted median (OR = 1.043, 95%CI: 0.941–1.156, p = 0.4239). The results of multivariable Mendelian randomization (MVMR) analysis, after adjusting for the confounding effect of smoking, suggest a potential causal relationship between periodontitis and COPD (P = 0.035). Conclusion In this study, periodontitis was found to be independent of COPD and a significant risk factor, providing new insights into periodontitis-mediated mechanisms underlying COPD development.

Abstract Heart injury such as myocardial infarction leads to cardiomyocyte loss, fibrotic tissue deposition, and scar formation. These changes reduce cardiac contractility, resulting in heart failure, which causes a huge public health burden. Military personnel, compared with civilians, is exposed to more stress, a risk factor for heart diseases, making cardiovascular health management and treatment innovation an important topic for military medicine. So far, medical intervention can slow down cardiovascular disease progression, but not yet induce heart regeneration. In the past decades, studies have focused on mechanisms underlying the regenerative capability of the heart and applicable approaches to reverse heart injury. Insights have emerged from studies in animal models and early clinical trials. Clinical interventions show the potential to reduce scar formation and enhance cardiomyocyte proliferation that counteracts the pathogenesis of heart disease. In this review, we discuss the signaling events controlling the regeneration of heart tissue and summarize current therapeutic approaches to promote heart regeneration after injury.

The field synergy principle is widely used in the analyses and optimizations of convective heat transfer, but its original derivations are based on fluids with constant thermal properties. The applicability of the principle for fluids with temperature-dependent properties needs clarification. A theoretical analysis of the problem is conducted. It is found that a synergy principle of mass flux vector and specific enthalpy gradient is more fundamental. Because temperature gradients are parallel to specific enthalpy gradients, the original field synergy principle of velocity and temperature fields is still valid. Heat transfer of supercritical CO2 and molten salt in different finned channels is numerically studied, and different mean synergy angles are compared. It is found that the domain integration mean synergy angles calculated with specific enthalpy gradient or temperature gradient have the same trends. For the volume-weighted mean angles, the absolute value of dot product of velocity and temperature gradient should be used in calculating the local synergy angles. Otherwise, the trend of the volume-weighted mean angles can be contrary to the field synergy principle. Meanwhile, the accuracy of the mesh and the temperature gradient near the heat transfer surfaces is important for the numerical applications of the field synergy principle.

This paper aims to study the low-cycle fatigue property and recovery properties of viscous material. The authors designed a Self-Stabilization Dynamic Sandwich-Type Shear (S-DSTS) test device, which allows the static recovery of semisolid materials that can not be achieved in the traditional rheometer. A series of recovery tests with different static recovery times and low-cycle fatigue tests with different strain amplitudes and loading frequencies were conducted on the polyisobutylene-B12 (PIB–B12) by this device. The test data on low-cycle fatigue and recovery properties of PIB-B12 were evaluated by the storage modulus, loss modulus, loss factor, velocity exponent, parameter decay ratio, and recovery coefficient. The results show that each parameter's degradation rate and degradation degree increase significantly with the rise of strain amplitude. The low-cycle fatigue property of PIB-B12 is less affected by the loading frequency, and the degradation rate and degradation degree of all parameters are similar under different loading frequencies. The PIB-B12 has excellent recoverability and static recovery showing that the mechanical parameters of PIB-B12 could restore to more than 65% and 92% of the original magnitude after short-term and long-term intervals, which ensures a reliable energy absorption property during aftershocks. The velocity exponent of PIB-B12 shows minor variations under different strain amplitudes and loading frequencies.

Abstract Background The relationship between triglyceride-glucose index (TyG index) and the prevalence and prognosis of cardiovascular disease has been confirmed by former studies. However, it remains uncertain whether TyG index has a prognostic impact in patients with type 2 diabetes mellitus (T2DM) and non-ST-segment elevation acute coronary syndrome (NSTE-ACS) undergoing percutaneous coronary intervention (PCI). Methods The study retrospectively enrolled 798 patients (mean age: 60.9 ± 8.3 years; 68.3% men) with T2DM and NSTE-ACS who underwent PCI at Beijing Anzhen Hospital from January to December 2015. TyG index was calculated as previously reported: ln [fasting TGs (mg/dL) * FBG (mg/dL)/2]. The primary endpoint was a composite of adverse events as follows: all-cause death, non-fatal myocardial infarction (MI) and ischemia-driven revascularization. Results TyG index was significantly higher in patients with a primary endpoint event compared with those without. Multivariate Cox proportional hazards analysis showed that 1-unit increase of TyG index was independently associated with higher risk of primary endpoint, independent of other risk factors [hazard ratio (HR) 3.208 per 1-unit increase, 95% confidence interval (CI) 2.400–4.289, P

Abstract Background It is uncertain whether estimated remnant-like particle cholesterol (RLP-C) could predict residual risk in patients with different glycometabolic status. This study aimed to evaluate the relationship between estimated RLP-C and adverse prognosis in patients with non-ST-segment elevation acute coronary syndrome (NSTE-ACS) treated with percutaneous coronary intervention (PCI) and to identify the potential impact of glycometabolism on the predictive value of estimated RLP-C. Methods The study assessed 2419 participants with NSTE-ACS undergoing PCI at Beijing Anzhen Hospital from January to December 2015. Estimated RLP-C was calculated as follows: total cholesterol (TC) minus low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C). The adverse events included all-cause death, non-fatal myocardial infarction (MI), and ischemia-driven revascularization. Results Estimated RLP-C was prominently associated with adverse prognosis in the total population [hazard ratio (HR) 1.291 per 1-SD increase, 95% confidence interval (CI) 1.119–1.490, P

In order to obtain the shockwave load simplified algorithm model for the semiarmored projectile internal explosion in the cabin, this research made use of AUTODYN to provide a numerical modeling method for explosion in the cabin and verified the accuracy of the method via the experiment. Internal explosion simulation calculation was conducted on the operating condition numerical model with different cabin structural dimensions and different explosive loads. The cabin internal explosion space was divided into the noncorner central area, near-wall area, two-sided corner area, and three-sided corner area. Through regression of the abovementioned calculation results, an engineering model to calculate the shockwave load was obtained. It is hoped that the model can offer some references to the antiexplosion design for the ship cabin and for damage assessment of the internal explosion.

Weathering has always been a concerned around the world, as the first and most important step in the global cycle of elements, which leads to the fractionation of isotopes on the scale of geological age. The Middle Ordovician Majiagou Formation in Daniudi area of the Ordos Basin had experienced weathering for >130 Myr. Through thin section observation, major and trace element analysis, carbon, oxygen, and magnesium isotopes composition analysis, the dolomitization modes and weathering of ancient dolomite in Daniudi area were analyzed in detail. The results showed that the Sabkha and brine-reflux dolomitization modes had developed, and the Mg isotopes in different layers of the karst crust were fractionated by various factors. The vertical vadose zone was affected by weathering, the Mg isotope of dolomite (δ26Mgdol) showed a downward decreasing trend; the horizontal underflow zone was controlled by diagenesis and formation fluid, β26Mgdol showed a vertical invariance and negative; the main reason for Mg isotope fractionation in the deep slow-flow zone was the brine-reflux dolomitization mode during early burial period, which showed a vertical downward increase. Finally, the Mg isotope characteristic data of the ancient weathering crust were provided and the process of Mg isotope fractionation in the karst crust was explained. [ABSTRACT FROM AUTHOR]