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A simplified column-buckling model is developed to understand the buckling mechanism of thin-walled strips restrained by uniform lateral pressure in the milling process. The strip is simplified as two rigid columns connected by a rotation spring, resting on a smooth surface, restrained by a uniform pressure and loaded by an axial force. Two loading cases are considered, i.e., the dead load and the follower load. Analytical solutions for the post-buckling responses of the two cases are derived based on the energy method. The minimum buckling force, Maxwell force and stability conditions for the two cases are established. It is demonstrated that the application of higher uniform pressure increases the minimum buckling force for the column and thus makes the column less likely to buckle. For the same pressure level, the dead load is found to be more effective than the follower load in suppressing the buckling of the system. The effect of initial geometric imperfection is also investigated, and the imperfection amplitude and critical restraining pressure that prevent buckling are found to be linearly related. The analytical results are validated by finite element simulations. This analytical model reveals the buckling mechanism of strips under lateral pressure restraint, which cannot be explained by the conventional bifurcation buckling theory, and provides a theoretical foundation for buckling-prevention strategies during the milling process of thin-walled strips, plates and shells commonly encountered in aerospace or automotive industries. [ABSTRACT FROM AUTHOR]

This paper examines the relationship between income inequality and consumption, utilizing panel data from rural China over a span of four years to validate the application of relative income theory in the domain of food consumption. Food consumption represents a significant portion of expenditures for the low-income demographic and is of vital importance to China's food security and agricultural development. To ascertain the impact of income inequality on food consumption, this paper employs a bi-directional fixed-effects model, a mediation effect model, and machine learning causal analysis methods. Utilizing four years of rural resident survey data from the China Health and Nutrition Survey database, the study empirically tests the effect of income inequality on various types of food consumption, the channels through which it operates, and the heterogeneity among different income groups and educational backgrounds. The findings indicate that (1) income inequality within rural communities positively influences food consumption, and this conclusion remains robust under endogeneity treatment and robustness checks, positively affecting the transformation of food consumption and healthy intake; (2) income inequality among rural residents promotes food consumption through two mediating channels: the "demonstration effect" and the "ratchet effect;" (3) the impact of income inequality on food consumption exhibits heterogeneity among rural residents of different income levels and educational backgrounds. [ABSTRACT FROM AUTHOR]

Many laboratory studies have shown that particle size distribution (PSD) affects the liquefaction susceptibility of granular materials. However, few studies have focused on the impact of PSD on coral particles. In this study, two different soil families were prepared: one with three levels of mean particle size (D50) with identical uniformity coefficient (Cu)and the other with four levels of Cu with the same D50 for coral gravelly soils. In addition, a series of undrained cyclic triaxial tests were conducted on coral gravelly particles with two groups of PSDs at a relative density of 40% and an adequate confining pressure of 100 kPa. The test results indicated that D50 with identical Cu can affect the undrained cyclic behavior of coral gravelly particles. In contrast, Cu with identical D50 does not impact the undrained cyclic behavior of coral gravelly particles. The developing pore water pressure was uniform when the sample was subjected to the same cyclic loading. For samples with changing D50 values of 2.35, 4.70, and 7.05 mm, increasing D50 improved the cyclic liquefaction resistance. For samples with changing Cu, increasing Cu in the range of 1.06–5.00 first increased and then decreased the liquefaction resistance. [ABSTRACT FROM AUTHOR]

One of the crucial issues in developing lead-free piezoelectric materials for actuator applications lies in how to achieve large strain responses. Herein, a strategy that strengthens the synergistic contribution of reversible phase transition and ferroelectric domain switching via modulating the ferroelectric-to-relaxor transition temperature (TF−R) was proposed to improve the strain level. Following this strategy, an enhanced strain response was attained by introducing Bi(Zn2/3Ta1/3)O3 (BZT) into Bi0.5(Na0.8K0.2)0.5TiO3 (BNKT) matrix. The enhanced bipolar strain (Sbi) of 0.50% and the unipolar strain (Suni) of 0.56% were obtained in BNKT-0.025BZT ceramic, respectively, with corresponding normalized strain d33* values of 833 and 933 pm/V (@60 kV/cm). Besides, BNKT-0.05BZT ceramic exhibited excellent energy storage behavior with a recoverable energy storage density Wrec of 1.05 J/cm3 at 90 kV/cm. These findings demonstrate that BNKT-xBZT ceramics are promising material candidates for actuators and energy storage applications. [ABSTRACT FROM AUTHOR]

One of the inherent disadvantages of Bi0.5Na0.5TiO3‐based (BNT‐based) piezoceramics is that an increment of the depolarization temperature (Td) is generally accompanied by a deterioration of the temperature stability of the real‐time piezoelectric constant (d33), which severely restricts the practical applications of the materials. Herein, we propose a new strategy to mitigate the conflict between the elevation of Td and the temperature stability of the real‐time d33 in BNT‐based ceramics via integrating the pressure‐assisted sintering and quenching process. By this strategy, we not only increased the Td from 109 to 166°C but also improved the temperature stability of the real‐time d33 (the temperature coefficient Ttc = ± 13 pC/N) in 0.94Bi0.5Na0.5TiO3–0.06BaTiO3 ceramic. Both the built‐in field and the increment of the field‐induced R3c phase fraction play the significant role in enhancing the Td and the temperature stability of the real‐time d33. Thus, our work provides a simple and effective approach for designing piezoceramics with high Td and a superior temperature stability of the real‐time d33. [ABSTRACT FROM AUTHOR]

Aim: To express the clinical characteristics of patients with post-neurosurgical meningitis (PNM) and launch a survival analysis to screen mortality predictors., Methods: A cohort analysis containing more than 70000 patients was evaluated, and all of them received neurosurgical procedure. Clinical and microbial epidemiology, therapy and mortality of PNM patients were reviewed. Multi-variable Cox proportional hazard models were applied to achieve survival analysis., Results: About 900 PNM patients from 3244 cases were selected for characteristics and survival analysis, the mean age of them was 41 (27-54) years, 516 (57.3%) were men and 384 (42.7%) were women. The 28-day mortality was 12.4% (112 of 900) in patients with PNM. Hypertension, external ventricular drainage (EVD), and lumbar drainage (LD) are mortality predictors for PNM, with a hazard ratio (HR) of 2.641 (95% C.I. 1.563-4.464, P<0.001), 2.196 (95% C.I. 1.317-3.662, P=0.003), and 1.818 (95% C.I. 1.126-2.936, P=0.014). In treatment, the outcome of patients receiving three or more antibiotic combinations is better than that of patients receiving dual-drug combinations., Conclusion: The mortality of patients with PNM was relatively high, and the risk factors related to 28-days mortality were hypertension, EVD and LD and treatment with three or more antibiotics are much better., Competing Interests: The authors have no conflicts of interest to disclose., (© 2024 Zheng et al.)