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SUMMARY: The tea plant (Camellia sinensis) is a perennial green plant, and its tender leaves are rich in secondary metabolites, such as theanine. Ethylamine (EA), a small amine, is an important prerequisite for theanine synthesis. However, beyond its involvement in theanine synthesis, the other physiological functions of EA in tea plants remain unknown. In vitro experiments indicate that EA may function as scavengers of reactive oxygen species (ROS) to protect the plant against damage caused by osmotic stress. Additionally, a significant correlation between EA levels and osmotic tolerance has been observed in different tea varieties. From the results, alanine decarboxylase (CsAlaDC)‐silenced tea leaves and overexpressed CsAlaDC Arabidopsis thaliana lines decreased and increased EA levels, respectively, and mediated ROS homeostasis, thus exhibiting a sensitive and tolerant phenotype. In addition, the transcription factor (TF) CsCBF4 was functionally identified, which can directly bind to the CsAlaDC promoter. CsCBF4‐silenced tea leaves significantly reduced the expression levels of CsAlaDC and in turn EA content, resulting in excess ROS accumulation and an osmotic‐sensitive phenotype. Taken together, these results established a new regulatory module consisting of CBF4‐CsAlaDC responsible for EA accumulation and ROS homeostasis in response to osmotic stress. Significance Statement: In this study, the important role of ethylamine (EA) in osmotic resistance of tea plants (Camellia sinensis) was reported for the first time and proposed a new way of CsCBF4‐CsAlaDC module‐mediated EA enhanced osmotic tolerance. [ABSTRACT FROM AUTHOR]

Y3+ : CaF2 powders were synthesized by chemical coprecipitation method, and transparent ceramics were fabricated by vacuum hot pressing sintering method. Characteristics of the as-synthesized powders were investigated by XRD, SEM and TEM techniques, the relationship between microstructure and transmittance of transparent ceramics were also analyzed. Crystal structures of as-synthesized Y3+ : CaF2 powders belong to single fluorite phase. With the Y3+ doping content increases, the average particles sizes decrease and the lattice constants increase from 5.452 1 Å to 5.465 5 Å. The 5% Y3+ :CaF2 transparent ceramics sintered at 900 °C for 3 h exhibits the highest transmittance, and the transmittance at 500 and 1 500 nm are 73. 1% and 86.4%, respectively. Microstructure of ceramics are modified by the Y3+ doping content and sintering temperatures. For a low growth velocity, it is not easy to eliminate the residual pores, while for a higher growth velocity, residual pores are easily embedded within grains. Both cases will reduce the transmittance of transparent ceramics. This work provides a reference for the preparation of high-quality composite CaF2 transparent ceramics. [ABSTRACT FROM AUTHOR]

[Objective] In order to explore the typical surface wind erosion process of the dry lake basin and the mechanism of the formation of saline-alkali dust storm. [Methods] Taking the Chagannaoer dry salt lake in Abaga Banner of Xilin Gol League as the research object, four different surface types (crust surface, broken surface, activated surface and desertification surface) were selected according to the dynamic evolution process of salt lake surface from the lake center to the lake shore. The characteristics of soil particle size distribution, wind speed profile and sediment transport law near the surface from the lake center to the lake shore were analyzed. [Results] (1) Extending from the center of the lake to the shore of the lake, the grain size of 0—2 cm sediment on the surface showed a trend of gradually thickening, and the clay and silt were the main particles. (2) The wind speed from the center of the dry salt lake to the shore of the lake showed a decreasing trend. Wind speed profiles of different surfaces generally followed the logarithmic distribution of Karman’s velocity, and the fitting effect was good (R2>0.90). (3) The amount of sediment transport on the broken surface was the highest, which was about 50 times that of the crust surface, and the sediment transport rate on the crust surface showed a linear law with the change of height due to limited dust supply (R2=0.80), and the sediment transport rate on the other three surfaces showed an exponential function with the change of height (R2>0.97). (4) Near the surface at a height of 0 to 50 cm, the average particle size of sand particles carried in the wind-sand flow ranges from 2 to 8 μm, which falled under the category of silt, with poor sorting. Skewness was predominantly negative, while kurtosis was mainly medium and sharp. [Conclusion] On the whole, the wind erosion effect on the broken surface was the strongest, and the wind erosion effect on the crust surface was the weakest. The wind erosion effect in this area can be weakened by increasing the critical starting wind speed threshold of sand particles and the coverage of underlying surface.

The effluent from the secondary sedimentation tank of the wastewater treatment plant of a liquor production enterprise in Guizhou was taken as the research object. Zero-valent iron（Fe0） activated persulfate（S2O82-，PS） advanced oxidation method was used to further treat the effluent，and the process conditions were optimized. The effects of initial pH，PS dosage and molar ratio of Fe0 to PS on the treatment effect of liquor wastewater were investigated by single factor experiment，and the process conditions were further optimized by response surface method. The results show that persulfate process can effectively reduce the organic content of liquor wastewater. The optimal process conditions are as follows：initial pH is 4.08，The PS dosage was 1.39 times the theoretical dosage （1 mg/L COD complete oxidation theoretically requires 12 mg/L PS），n（Fe0）∶n（PS）=1.27. Under these conditions，the COD removal rate of liquor wastewater reaches 70.33%.

In this study, three coupled modes of coupling effect of sulfate attack and carbonation of concrete were carried out to investigate the change of mass, mechanical properties and apparent morphology. The phase composition, microstructure and morphological characteristics of erosion products were also studied by using environment scanning electron microscope (ESEM-EDS), Fourier infrared spectrometer (FTIR), and X-ray diffraction (XRD). The results indicated that the coupled mode played an obvious effect on the performance and microstructures of specimen due to effects of coupled mode on the deterioration mechanism and erosion products. The surface feature of specimen became worse with carbonation time, and plenty of surface efflorescence and desquamation of products were observed under the coupled mode of carbonation followed by sulfate attack. The relative compressive strength and dynamic elastic modulus of concrete specimen first increased and then decreased with carbonation time, and there existed relationship of a cubic function of single variable between them. The relative mass of concrete specimen increased with the increase of the erosion age of sulfate attack. The difference of the carbonation time per period test played a significant effect on the relative compressive strength and dynamic elastic modulus of concrete specimen, which was due to the dominant effect of carbonation.

Digital technology, at the center of the fourth technological revolution, is currently transforming all aspects of people’s lives and learning in an unprecedented manner. In light of the ongoing advancements in education technology, this study introduces an enhanced C-ADDIE teaching model, which is competence-oriented and builds on the foundation of the traditional ADDIE model while also catering to the needs of students majoring in digital animation. The enhanced fuzzy clustering algorithm establishes a portrait of the student’s behavior, followed by the introduction of a multi-attention mechanism that builds a digital professional student performance prediction model and a supplementary teaching system. We are developing a teaching model that integrates digital technology with the C-ADDIE model. The testing of the teaching system reveals that the grade prediction accuracy ranges from 88% to 98%, with an average prediction accuracy of 93.02%. The average response time is 1.5ms, the CPU usage remains stable between 5% and 23%, and the overall performance of the teaching system is good. The results of the teaching experiment show that the average grade of the teaching mode of this paper is 5.28 points higher than the average grade of the traditional teaching mode, and at the same time, it also has a significant effect on the improvement of knowledge cultivation, artistic expression and creativity, and artistic aesthetic cultivation of artistic literacy (P

As the wave of industrial intelligence (AI) swept, the demographic dividend era in the Chinese labor market continued to decrease. This study aimed to explore how AI reshaped the labor employment structure of the floating population. Additionally, it clarified the internal mechanism of AI on the employment structure of the floating population based on the existing AI model and the theoretical model of AI technology. At the same time, the workforce was divided into high-, medium-, and low-skilled groups according to education level. Empirical analysis was conducted using relevant data from 31 Chinese provinces spanning from 2012 to 2018. The aim was to test the impact of AI technology on the employment of different types of floating populations. The results indicated that: (1) industrial robots impacted heterogeneous skilled floating population labor by bipolar promotion and central substitution. (2) The application of industrial robots had a promotion effect on unfinished school and primary school groups, a substitution effect on middle school, high school/technical secondary school, and college specialties, and a promotion effect on college undergraduate and graduate students. (3) Distinguish employment status, industrial robot application had a significant negative impact on low-skilled employees and significant positive effects on high-skilled employers. Hence, it was recommended to put forward corresponding policy suggestions to address this issue.

One of the key difficulties confronting universities today is how to use the current technology to raise educational standards and support educational reform. This is due to the ongoing growth of network technology. This study primarily explores the collaborative filtering recommendation algorithm-based recommendation model for college civics teaching materials. Analyzed are both the functional and non-functional demands for collegiate civic and political science teaching materials. For these requirements, the collaborative filtering recommendation algorithm is put out, and it is enhanced so that it may be applied in real-world settings. In order to execute the model, the system architecture and process are established, and the impacts of teaching interventions are used to examine the outcomes of the suggested practical teaching of civic and political science teaching materials in colleges and universities. The findings revealed that the p-values of the significance probabilities were, respectively, 0.056, 0.007, and 0.235 for the entrance exam and the first semester final examination, the entrance examination and the second semester final examination, and the first semester final examination and the second semester final examination. The collaborative filtering recommendation algorithm-based recommendation model for teaching resources recommendation of university thinking and politics proposed in this paper is effective in enhancing students’ learning autonomy and promoting the exchange of ideas. It has a certain effect.

Biomolecular condensates formed by phase separation are involved in many cellular processes. Dysfunctional or abnormal condensates are closely associated with neurodegenerative diseases, cancer and other diseases. Small molecules can effectively regulate protein phase separation by modulating the formation, dissociation, size and material properties of condensates. Discovery of small molecules to regulate protein phase separation provides chemical probes for deciphering the underlying mechanism and potential novel treatments for condensate-related diseases. Here we review the advances of small molecule regulation of phase separation. The discovery, chemical structures of recently found small molecule phase separation regulators and how they modulate biological condensates are summarized and discussed. Possible strategies to accelerate the discovery of more liquid-liquid phase separation (LLPS)-regulating small molecules are proposed.

In order to research influence of gas on surface potential of coal containing gas under cyclic loading, an experimental system about surface potential of coal containing gas under cyclic loading was built. Characteristic laws of surface potential signals were tested and analyzed in coal destruction process by cyclic loading under different gas pressure, and mechanism of loaded destruction of coal containing gas was discussed. The experimental results show that coal containing gas can produce surface potential signal in loaded destruction process, and the surface potential signal has some relevance with stress and gas change. For the same type of coal samples, stress level under the maximum surface potential decreases as gas pressure increases. The surface potential signals obviously increases when stress is larger than the last maximum during cyclic loading.

As research on the full spectrum of ecosystem service (ES) generation and utilization within coupled human and natural systems (CHANS) has expanded, many studies have shown that the spatiotemporal dynamics of ESs are managed and influenced by human activities. However, there is insufficient research on how ESs are affected by bidirectional coupling between societal and ecological factors during spatial flow, particularly in terms of cross-scale impacts. These bidirectional influences between humans and nature are closely related to the utilization and transfer of ESs and affect the perception of spatiotemporal patterns of ESs and the formulation of management strategies. To fill this research gap, this study focuses on the Yellow River Basin (YRB), using network models to track the spatial dynamics of ES flows (ESFs) and the interactions between ecosystems and socio-economic systems within the basin on an annual scale from 2000 to 2020. The results highlight cross-scale impacts and feedback processes between local subbasins and the larger regional basin: As the supply–demand ratios of freshwater ESs, soil conservation ESs, and food ESs increase within individual subbasins of the YRB, more surplus ESs flow among subbasins. This not only alleviates spatial mismatches in ES supply and demand across the entire basin but also enhances the connectivity of the basin's ESF network. Subsequently, the cascading transfer and accumulation of ESs feedback into local socio-ecological interactions, with both socio-economic factors and the capacity for ES output within subbasins becoming increasingly reliant on external ES inflows. These results underscore the crucial role of ESFs within the CHANS of the YRB and imply the importance of cross-regional cooperation and cross-scale management strategies in optimizing ES supply–demand relationships. Furthermore, this study identifies the potential risks and challenges inherent in highly coupled systems. In conclusion, this work deepens the understanding of the spatial flow characteristics of ESs and their socio-ecological interactions; the analytical methods used in this study can also be applied to research on large river basins like the YRB, and even larger regional ecosystems. • Network analysis of dynamics of ecosystem service flows in the Yellow River Basin. • Service reallocation along the flow net reduces gaps and enhances basin connectivity. • Cross-scale effect between socio-ecological interactions and ecosystem service flows. • Flow network changes bring optimization opportunities and potential challenges. • Stress the value of cross-regional service flow and proactive allocation in the basin. [ABSTRACT FROM AUTHOR]

Mixed-valence compounds are of great interest due to their interesting properties and wide applications. Recently, gold (Au) chemistry has experienced an unprecedented development. However, Au with mixed-valence states in Au-O compounds has not been reported thus far. Here, two hitherto unknown AuO 2 and AuS compounds with mixed-valence character were identified with the aid of first-principles swarm structure searching calculations. AuO 2 consists of quasi-square AuO 4 moiety and AuO 6 octahedron in which Au shows the mixed-valence states of III and V, the first example in Au-O binary compounds. AuS contains the linear AuS 2 and quasi-square AuS 4 units exhibiting Au I/III mixed-valence states. The analysis of electronic property demonstrates that AuO 2 and AuS are narrow band gap semiconductors with strong hybridization between Au 5d and O 2p or S 3p. With the increase of pressure, Au-O and Au-S compounds show completely different thermodynamic stabilities, resulting from distinct shifting of pressure-induced atomic orbital energy levels of O and S atoms. Our work provides an opportunity for understanding mixed-valence character in Au-O and Au-S compounds., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)