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The coronavirus disease 2019 outbreak has the potential to trigger declines in individual mental health, potentially in the form of depressive symptoms. However, few studies have explored factors protective of mental health during the ongoing pandemic. For the sustainable development of individual health, this study was conducted during the pandemic and examines the relationship between gratitude and symptoms of depression, as well as the moderating effect of psychological capital. Latent variable structural equation modeling was used to analyze depressive symptoms and protective factors in 3123 college students. This study measures gratitude, depressive symptoms, and psychological capital, using the Gratitude Scale, Patient Health Questionnaire-9, and the Positive Psychological Capital Questionnaire, respectively. Gratitude was negatively related to depressive symptoms, with psychological capital as a moderator of the relationship. Specifically, psychological capital had a powerful protective effect against depressive symptoms. Students with high psychological capital had lower depressive symptoms than those with low psychological capital, regardless of their level of gratitude. In students with low psychological capital, gratitude had a protective effect against depressive symptoms. These findings suggest that psychological capital is a powerful protective factor against depressive symptoms during a pandemic and improving psychological capital could enhance mental health.

The optical microscope, scanning electron microscope, electron backscattered diffraction and three-dimensional atom probe techniques were employed to investigate the morphology, distributions of alloy elements and orientation of blocky α phase in β forging TC17 titanium alloy. The results show that the blocky α phases are distributed nearby the grain boundary, inside the prior β grains and recrystallized grains, while abnormal microstructure such as long and coarse α lamellar can also be observed inside the grains. There is no significant difference in the distribution of main elements between all kinds of abnormal α and β matrix phase. Therefore, the segregation of alloy composition does not cause the blocky α phase. The acicular α phase is randomly distributed in the grain and is acicular or cotton-blocky under the microscope. In addition, the orientation of α phase is also a main factor determining lamellar morphology. Coarse lamellar and agglomerate blocky α phase can be observed inside the fine recrystallized grains and slightly deformed grains. The fine recrystallized grains represent the undeformed or slightly deformed grains, which grain boundary α and α platelets inside the grain are basically single in orientation. Therefore, the α phase with the same orientation is easy to agglomerate under slow cooling. In addition to the dispersed cotton-blocky α phase, it also appears as blocky α phase which run through the entire grain or agglomerate near the grain boundary.

Klotho is an anti-aging protein and can be divided into three types: full-length transmembrane Klotho, soluble Klotho and secreted Klotho. Many studies have shown that Klotho is closely related to oxidative stress, inflammatory response, myocardial hypertrophy, fibrosis, autophagy, and mitochondrial dysfunction. It is also involved in the occurrence and development of heart failure. It is expected to provide a new target and direction for the treatment of heart failure.

As a key factor influencing the cloud life cycle and radiative properties, liquid‐ice mass partitioning remains a major source of uncertainties in modeling mixed‐phase clouds. One of the unresolved problems is that liquid‐ice mixing is highly inhomogeneous, but it has not been well understood and quantified for parameterization. In this study, the liquid‐ice mixing homogeneity (χ) is quantified using the information‐theoretic entropy based on airborne measurements. It is demonstrated that χ is positively correlated with the condensed water content (CWC). Cloud regions with low χ are consist of liquid and ice clusters. With the increase in χ, the size and frequency of continuous mixed‐phase clusters increase. For a given CWC, χ is lower at relatively warm temperatures as sedimentation of large ice crystals can enhance the inhomogeneity. The strong positive relationship between CWC and χ indicates CWC should be considered when parameterizing the liquid‐ice mixing in models. Plain Language Summary: Mixed‐phase clouds consist of water vapor, supercooled droplets, and ice particles. The complex liquid‐ice interactions have a substantial influence on the macrophysical and microphysical characteristics of the clouds, which ultimately affect the global water cycle and radiative balance. Observations and model experiments have shown that liquid and ice are not uniformly mixed, and the liquid‐ice mixing homogeneity also strongly affects the cloud glaciation processes. However, the liquid‐ice mixing homogeneity is still not well understood and is poorly represented in numerical models. In this study, based on airborne measurements, the liquid‐ice mixing homogeneity is quantified. It is found that there is a positive correlation between mixing homogeneity and the condensed water content, while the latter is a predictable value in models. These results provide a new idea to constrain the liquid‐ice mixing in models and are potentially helpful to improve the model simulation of mixed‐phase clouds. Key Points: Liquid‐ice mixing homogeneity is quantified using information‐theoretic entropy and airborne measurementsCondensed water content is positively related to liquid‐ice mixing homogeneity in mixed‐phase cloudsCondensed water content and temperature should be considered in parameterization of liquid‐ice mixing homogeneity [ABSTRACT FROM AUTHOR]

The microstructural stability and property evolution of high-temperature titanium alloys under long-term high-temperature conditions has been a critical scientific issue in the field of advanced titanium alloys. In this work, we systematically investigated the precipitation behavior of silicides and ordered α2 phase, which are closely related to the microstructural stability of Ti65 high-temperature alloy, during thermal exposure at 650 °C for different periods of time. Furthermore, the effects of thermal exposure on mechanical properties were evaluated using room temperature and high temperature tensile tests, and subsequently, the correlation between the microstructural thermal stability and the mechanical characteristics was discussed. The results reveal that (Ti, Zr)6Si3 silicides initially precipitate within the residual β film and then start to precipitate in the α platelet. A large number of fine spherical α2 precipitates were formed inside the α platelet after a short thermal exposure. The number density of ordered α2 decreased significantly after 1000 h due to Ostwald ripening. The precipitation of silicides and ordered α2 phases during thermal exposure improves the tensile strength but deteriorates the ductility, and the room-temperature ductility is slightly restored due to α2 ripening after long-time thermal exposure. Ti65 high-temperature titanium alloy consistently maintains favorable room-temperature tensile properties throughout long-term thermal exposure. [ABSTRACT FROM AUTHOR]

Geopolymer cementitious materials and recycled aggregate are typical representatives of material innovation research in the engineering field. In this study, we experimentally investigated a method to improve the performance of geopolymer-recycled aggregate concrete (GRAC). The recycled concrete aggregates and steel fiber (SF), fly ash (FA), metakaolin (MK), and sodium silicate solution were used as the main raw materials to prepare fiber-reinforced geopolymer-recycled aggregate concrete (FRGRAC). First, the orthogonal test was carried out to study the GRAC, and the optimal mix proportion was found. Second, building on the optimal mix proportion, the effects of the SF content on the slump, 7 and 28 days compressive strength, tensile strength, and flexural strength of FRGRAC were further studied. Finally, the microscopic mechanism of FRGRAC was studied by scanning electron microscopy (SEM). The study results indicate that the slump continues to decrease as the fiber content increases, but the compressive strength, tensile strength, and flexural strength increase to a certain extent. Through SEM analysis, it is found that SF restrains the development of cracks and improves the strength of concrete.

Based on panel data for 30 provinces in China from 2000 to 2020, this paper uses entropy method to construct the integrated development indicators of energy Internet, and explores the impact of the development of the energy Internet on reducing carbon emissions in China and its internal transmission mechanism. The research results show that the development of energy Internet can significantly reduce regional carbon dioxide emissions, and increasing the use of renewable energy is an important mechanism for the comprehensive development of energy Internet to curb carbon emissions. Heterogeneity analysis shows that the emission reduction effect brought by the development of energy Internet is more remarkable in the regions with lower carbon emissions and western China. Furthermore, this paper finds that in the setting of the development of energy Internet, the development of renewable energy can promote natural gas consumption and advance energy conversion efficiency. The government's emphasis on regional technology development has an external strengthening effect on carbon emission reduction. The research in this paper expands and diversifies carbon reduction pathways and provides reference for more developing countries to utilize the development of energy internet to achieve carbon reduction. [ABSTRACT FROM AUTHOR]

In mixed‐phase cumulus clouds, droplets and ice crystals are inhomogeneously distributed, such spatial inhomogeneity can be enhanced by inhomogeneous entrainment as it can strengthen the particle clustering, which may further influence the phase partitioning and interactions among hydrometeors. However, the scale of particle clustering induced by inhomogeneous entrainment is not well known. Utilizing high‐resolution in‐situ aircraft measurements in mixed‐phase cumulus clouds, this study shows due to inhomogeneous entrainment‐mixing, the cluster scales of droplets and ice crystals decrease by approximately 10 m from the cloud center to the edge. Changes in the clustering are correlated with the intensity of entrainment‐mixing. Clouds that are significantly affected by entrainment exhibit stronger enhancement of particle clustering and a more noticeable reduction in cluster scale. The findings from this study improve our understanding of the scale of particle clustering induced by entrainment‐mixing, and are potentially helpful in evaluating models. Plain Language Summary: Entrainment‐mixing is one of the key processes controlling cloud life cycle and the spatial distribution of hydrometeor. It is known that inhomogeneous entrainment mixing would enhance the clustering of particle distribution in cumulus clouds, but the scales of droplet and ice clusters induced by inhomogeneous entrainment have not been quantified. Utilizing high‐resolution aircraft data sampled in mixed‐phase cumulus clouds, we showed that extreme inhomogeneous entrainment‐mixing fosters pronounced clustering of both droplet and ice particles. Opposite gradients in cluster index and cluster scale from the cloud center to the edge under varying temperature conditions are discovered. On average, the droplet and ice cluster scales decrease by 10 m due to the entrainment. In clouds that undergo intense entrainment, the amplified particle clustering is more discernible and the decrease of cluster scale is markedly greater from the cloud center to the edge. The results enhance the comprehension by quantification of extreme inhomogeneous entrainment‐mixing and are potentially helpful for assessing the performance of model simulations. Key Points: The scales of droplet and ice crystal clustering in mixed‐phase cumulus clouds are quantified using airborne in‐situ measurementsThe inhomogeneous entrainment‐mixing enhances particle clustering near cloud edge, with cluster scales decreasing by 10 m on averageClustering variation is related to the intensity of entrainment, stronger mixing leads to a more substantial decrease in cluster scales [ABSTRACT FROM AUTHOR]