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A deformed superalloy with γ′ content reaching 73% has been designed by ourselves. In this work, the problems of preparation and deformation caused by the high γ′ phase content were solved by the electron beam smelting layered solidification technique (EBS-LST) and hot extrusion. Initially, the superalloy with low segregation and fine microstructure was prepared by EBS-LST, followed by conducting hot deformation experiments at different temperatures and strain rates. The compression curves are corrected, and the constitutive model, recrystallization models and thermo-mechanical processing maps were established based on the corrected curves, and the recrystallization mechanisms were analyzed by TEM and EBSD. Finally, the suitable hot extrusion parameters were obtained indirectly through the hot processing map, and the designed alloy was hot extruded. The microstructure of the extruded alloy is free of cracks and is characterized by fine equiaxed grains.

Abstract Background A stable public health workforce plays an indispensable role in the realization of the goal of health for all. However, there is an exodus of public health workers from the Centers for Disease Control and Prevention (CDC). Given the limited evidence on the mechanisms shaping turnover intention (TI) among public health workers, the study aims to investigate the triggering mechanisms of high and low turnover intention by combining job demands, job resources, and personal resources through a set theory perspective based on the Job-Demand-Resources (JD-R) model. Methods The cross-sectional study was conducted from September 7 to 18, 2020 at district (county) level CDC in Liaoning Province, China. A total of 584 public health professionals were included. Overcommitment, effort, social respect, occupational identity, job rewards, self-efficacy, and psychological resilience were included in the study as configuration factors. The data were gathered through an online questionnaire and were analyzed using multiple regression and fuzzy-set Qualitative Comparative Analysis (fsQCA). Results Social respect (B = -0.682, P

Abstract Background The shortage of public health personnel and the uneven distribution between urban and rural areas are thorny issues in China. Master of public health (MPH) is an integral part of public health human resources in the future, and it is of far-reaching significance to discuss their work preferences. The present study wants to investigate the job preference of MPH, understand the relative importance of different job attributes, and then put forward targeted incentive measures. Methods Discrete choice experiment (DCE) was used to evaluate the job preference of MPHs in two medical colleges in Liaoning Province. Attributes include employment location, bianzhi, working environment, career development prospects, work value and monthly income. Thirty-six choice sets were developed using a fractional factorial design. Mixed logit models were used to analysis the DCE data. Results The final sample comprised 327 MPHs. All the attributes and levels included in the study are statistically significant. Monthly income is the most important factor for MPHs. For non-economic factors, they value career development prospects most, followed by the employment location. Respondents’ preferences are heterogeneous and influenced by individual characteristics. Subgroup analysis showed that respondents from different family backgrounds have different job preferences. Policy simulation suggested that respondents were most sensitive to a salary increase, and the combination of several non-economic factors can also achieve the same effect. Conclusions Economic factors and non-economic factors significantly affect the job preference of MPHs. To alleviate the shortage and uneven distribution of public health personnel, more effective policy intervention should comprehensively consider the incentive measures of the work itself and pay attention to the individual characteristics and family backgrounds of the target object.

Hypertension is a leading cause of morbidity and mortality worldwide and poses a major risk factor for cardiovascular diseases and chronic kidney disease. Research has shown that nitric oxide (NO) is a vasodilator that regulates vascular tension and the decrease of NO bioactivity is considered one of the potential pathogenesis of essential hypertension. The L-arginine-nitric oxide synthase (NOS) pathway is the main source of endogenous NO production. However, with aging or the onset of diseases, the function of the NOS system becomes impaired, leading to insufficient NO production. The nitrate–nitrite–NO pathway allows for the generation of biologically active NO independent of the NOS system, by utilizing endogenous or dietary inorganic nitrate and nitrite through a series of reduction cycles. The oral cavity serves as an important interface between the body and the environment, and dysbiosis or disruption of the oral microbiota has negative effects on blood pressure regulation. In this review, we explore the role of oral microbiota in maintaining blood pressure homeostasis, particularly the connection between nitrate-reducing bacteria and the bioavailability of NO in the bloodstream and blood pressure changes. This review aims to elucidate the potential mechanisms by which oral nitrate-reducing bacteria contribute to blood pressure homeostasis and to highlight the use of oral nitrate-reducing bacteria as probiotics for oral microbiota intervention to prevent hypertension.

Photodynamic therapy (PDT) is an effective method for treating microbial infections by leveraging the unique photophysical properties of photosensitizing agents, but issues such as fluorescence quenching and the restricted generation of reactive oxygen species (ROS) under hypoxic conditions still remain. In this study, we successfully synthesized and designed a coumarin-based aggregation-induced emission luminogen (AIEgen), called ICM, that shows a remarkable capacity for type I ROS and type II ROS generation. The 1O2 yield of ICM is 0.839. The ROS it produces include hydroxyl radicals (HO•) and superoxide anions (O2•−), with highly effective antibacterial properties specifically targeting Staphylococcus aureus (a Gram-positive bacterium). Furthermore, ICM enables broad-spectrum fluorescence imaging and exhibits excellent biocompatibility. Consequently, ICM, as a potent type I photosensitizer for eliminating pathogenic microorganisms, represents a promising tool in addressing the threat posed by these pathogens.

Droop control is widely used in multi-terminal flexible DC (VSC-MTDC) transmission systems by virtue of the advantage of multi-station cooperative unbalanced power dissipation, however, the essence of the droop control strategy is to change the DC current to realize the unbalanced power dissipation, and the resulting DC voltage deviation will affect the normal operation of the system. Firstly, this paper theoretically analyses the working characteristics of the conventional droop control and proposes a control method to realize the quasi-differential-free regulation of DC voltage by translating the droop curve. Second, according to the power margin of the converter station, the feedforward compensation amount of each converter station is reasonably set to avoid the power impact on the converter station. Finally, for the problem that the actual value of DC voltage still deviates from the rated value, a control strategy containing secondary regulation of DC voltage is proposed to further restore the DC voltage to the initial value on the basis of ensuring the effect of power regulation, which improves the stability of the operation of the VSC-MTDC system. The final simulation results verify the effectiveness of the proposed method.

Extracellular vesicles (EVs) are tiny lipid bilayer-enclosed membrane particles released from a variety of cell types into the surrounding environment. These EVs have massive participated in cell-to-cell communication and interspecies communication. In recent years, plant-derived extracellular vesicles (PDEVs) and “exosome-like” EVs populations found in distinct plants have attracted widespread attention. Especially, research on medicinal plant-derived extracellular vesicles (MPDEVs) are increasing, which are considered a kind of promising natural compound. This review summarizes current knowledge on MPDEVs in terms of bioactive compounds, including small RNA, protein, lipid, and metabolite, have been found on the surface and/or in the lumen of MPDEVs. Moreover, both in vitro and in vivo experiments have shown that MPDEVs exert broad biomedical functions, such as anti-inflammatory, anticancer, antioxidant, modulate microbiota, etc. MPDEVs may be a better substitute than animal-derived extracellular vesicles (ADEVs) because of safety and biocompatibility in the future.

This study examined the mediating effects of cognitive empathy and affective empathy in the relationship between dispositional awe and prosocial behaviour in medical students, and whether perceived stress moderated this association. A total of 631 medical students from two medical tertiary institutions in Liaoning Province, China, participated in this survey. The findings revealed that (1) dispositional awe was positively associated with prosocial behaviour; (2) the positive association between dispositional awe and prosocial behaviour was partially mediated by cognitive empathy and affective empathy; (3) perceived stress significantly attenuated the association between dispositional awe and cognitive empathy, and the association between cognitive empathy and prosocial behaviour. The findings yield practical implications for the improvement strategies of prosocial behaviour among medical students and provide suggestions for future educational interventions.