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Background Cardiovascular disease (CVD) is a major cause of human mortality worldwide, characterized by its insidious onset, intricate and variable course, and poor prognosis. Early identification and active intervention of potentially critically ill patients is essential to improve their prognosis. Objective To conduct a scoping review of the research on early warning assessment tools for cardiovascular disease risk at home and abroad, summarize and analyze their assessment content and application, ultimately providing reference for the selection of appropriate early warning tools for cardiovascular disease patients in China. Methods CNKI, Wanfang Data, VIP, CBM, PubMed, Web of Science, Cochrane Library, Embase, CINAHL, and Scopus were systematically searched from inception to May 2023. Two investigators independently screened literature and extracted data, analyzed in terms of assessment content, study subjects, validation method, reliability and validity, and predictive efficacy. Results A total of 16 papers were included, comprising 7 papers on the development and validation of assessment tools and 9 papers on the localized application of these tools, involving 20 early warning assessment tools for cardiovascular disease risk. The results of the analysis showed that each assessment tool contained 3 to 17 assessment items, with the most frequently mentioned items of age, systolic blood pressure, respiratory rate, oxygen saturation, heart rate, comorbidities, level of consciousness, and gender. The results of the reliability and validity tests for 2 papers indicated robust reliability and validity, while all other studies lacked reliability and validity evaluations. Ten papers reported the area under the curve (AUC), with values ranging from 0.550 to 0.926 9. Conclusion Diverse early warning assessment tools for cardiovascular disease risk are available, however, their overall quality remains to be improved and there is a lack of specific assessment tools. In the future, it is imperative to conduct further validations of the reliability and validity of the existing tools, and develop localized early warning assessment tools specialized for cardiovascular diseases considering the unique characteristics of the disease, which exhibit robust reliability and validity.

Development of high-performance cutting tool materials is one of the critical parameters enhancing the surface finishing of high-speed machined products. Ti(C,N)-based cermets reinforced with and without different contents of silicon nitride were designed and evaluated to satisfy the requirements. In fact, the effect of silicon nitride addition to Ti(C,N)-based cermet remains unclear. The purpose of this study is to investigate the influence of Si3N4 additive on microstructure, mechanical properties, and thermal stability of Ti(C,N)-based cermet cutting tools. In the present work, α -Si3N4 "grade SN-E10" was utilized with various fractions up to 6 wt.% in the designed cermets. A two-step reactive sintering process under vacuum was carried out for the green compact of Ti(C,N)-based cermet samples. The samples with 4 wt.% Si3N4 have an apparent solid density of about 6.75 g/cm3 (relative density of about 98 %); however, the cermet samples with 2 wt.% Si3N4 exhibit a superior fracture toughness of 10.82 MP a.m 1 / 2 and a traverse rupture strength of 1425.8 MPa. With an increase in the contents of Si3N4, the Vickers hardness and fracture toughness of Ti(C,N)-based cermets have an inverse behavior trend. The influence of Si3N4 addition on thermal stability is clarified to better understand the relationship between thermal stability and mechanical properties of Ti(C,N)-based cermets. [ABSTRACT FROM AUTHOR]

Nanoeutectic oxide layers have been obtained by laser surface nanocrystallization on oxide ceramics with eutectic composition. The eutectic layer can effectively improve the surface performance of oxide materials. This paper provides a comprehensive review of this promising technique. It includes the numerical simulation of temperature field in the melt pool associated with laser surface melting, formation mechanisms and growth kinetics of the coupled nanoeutectic structure, and the influence of processing parameters on structure and properties of eutectic oxide layer. In combination with other preparation techniques, such as directional solidification and additive manufacturing methods, the formation mechanism and prevention of bubbles and cracks are clarified. The relationship between microstructure and performance with gradient feature is also indicated. This review attempts to inspire imaginations and insights into material design and process optimization for laser surface nanocrystallization of oxide ceramics with eutectic composition. [ABSTRACT FROM AUTHOR]

[Display omitted] • The mechanism of phase transition from X2-RE 2 SiO 5 to apatite is revealed. • The formation of apatite in corroded Y 2 SiO 5 is inhibited by introducing Yb. • Silica-rich grain boundary is considered to reduce the corrosion degree. Environmental barrier coatings (EBCs) are usually coated on SiC ceramic or ceramic matrix composites (CMCs), in order to prevent the attack from corrosive media like water vapor and molten oxides. Solid-solutionizing strategy containing high-entropy engineering is considered as an effective way to mediate corrosion resistances of rare-earth silicates, which are promising candidates for the topcoats of EBCs. In this work, high-temperature corrosion behaviors of hot-pressed (Y 1− x Yb x) 2 SiO 5 ceramics have been investigated in a 50 %H 2 O–50 %O 2 environment at temperatures of 1573/1673/1773 K for 100 h. The main corrosion product of Y 2 SiO 5 is apatite phase, whose formation can be distinctly inhibited by introducing Yb. Consequently, introducing Yb avoids the tensile stress and cracks effectively, which are induced by the volume reduction due to the phase transition to apatite at elevated temperatures. The inhibition of apatite formation by introducing Yb is attributed to the relatively lower volatilization pressure of Yb 2 O 3 than Y 2 O 3 and the smaller cationic radius of Yb3+ than Y3+. Meanwhile, the composition deviations between grain boundary and grain surface results in the grain surface corrosion and ridge-like corrosion characteristics. [ABSTRACT FROM AUTHOR]