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This paper reports a controllable gradient microstructure sheet fabricated at room temperature conditions by a severe plastic deformation method, called plastic flow machining (PFM). The forming mechanism, microstructure evolution, and mechanical properties of the gradient-structured sheet for different machining parameters were investigated in detail. Results show that the prepared sheet by the PFM process is stratified into three structured surface layers, deformed grains layer (DGL), transition layer (TI), and ultrafine grains layer (UGL) from top to bottom, whereas microstructures present layer-by-layer refinement. The gradient structure can be controlled by adjusting the constraint tool angle and extrusion thickness in PFM. The gradient-structured sheet exhibits the concurrent combination of strength and ductility by comparison with homogeneous counterparts. It confirms that the extraordinary strength-ductility balance comes from the gradient structural effect. The insights in this study show that the continuous sheet production by PFM has superior performance and application perspectives in the structural materials, which can offer an effective and practicable one-step approach for low-cost fabricating the gradient-structured material.

BackgroundCardiovascular disease (CVD) is a global health concern, with a significant impact on morbidity and mortality rates. Using fasting glucose, fasting triglycerides, body mass index (BMI), and high-density lipoprotein cholesterol (HDL-C), the metabolic score of insulin resistance (Mets-IR), a novel index created by Mexican researchers to assess insulin sensitivity, is a more precise way to measure insulin sensitivity. This study aimes to explore the association between Mets-IR and CVD, as well as investigate the potential mediating role of of low-density lipoprotein cholesterol (LDL-C).MethodsThe study’s data came from the 2011 and 2018 China Health and Retirement Longitudinal Studies (CHARLS). We used three logistic regression models to account for the potential effects of ten factors on cardiovascular disease/stroke/heart disease. Moreover, We performed mediation analyses to evaluate the role of LDL-C in the association between Mets-IR and incident CVD.ResultsThis study comprised 4,540 participants, of whom 494 (10.88%) were found to develop disease (CVD). Each interquartile range (IQR) increased in Mets-IR raised the risk of developing CVD by 38% (OR=1.38; 95% CI, 1.21-1.56) and there was a linear dose-response relationship between Mets-IR and the risk of new-onset cardiovascular disease, stroke, and heart disease (Poverall0.05). Approximately 5% (indirect effect/total effect) of the significant association of Mets-IR with stroke was mediated by LDL-C, respectively. With the addition of Mets-IR to the base model, the continuous net reclassification improvement and integrated discrimination improvement for predicting cardiovascular disease increased by 0.175 (P

Background: A large amount of research is available on the relationship between socioeconomic status (SES) and hypertension. However, the relationship between SES and prehypertension remains complex and unclear. Prehypertension is defined as a systolic blood pressure (SBP) between 120 and 139 mmHg or diastolic blood pressure (DBP) 80 and 89 mmHg. This paper focuses on the impact of SES on the prevalence of prehypertension and provides suggestions for the prevention and control measures of prehypertension and health resource allocation. Method: Using multistage random sampling, 11,773 subjects were selected. Subjects aged above 15 years old and subjects who had been living in the eight selected districts for more than 6 months were analyzed using a multivariable logistical model. Results: The prevalence of prehypertension at the present time reaches 55.17%, with it being higher among men than that among women (63.15% vs. 47.19%, p