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Based on the engineering background that rock masses of underground reservoirs in mines are frequently disturbed by cyclic loads such as mine earthquake and mining stress, uniaxial compression and cyclic loading tests for sandstones with different water contents were carried out in laboratory. The crack propagation and failure laws of sandstones with different water contents were revealed by digital speckle technique. Based on scanning electron microscopic (SEM) analysis, the micro deterioration mechanism of sandstones with different water contents under cyclic loading was obtained. The test results show that the peak strength of sandstone decreases gradually with the increase of water content under both uniaxial compression and cyclic loading conditions. The peak axial strain variation of dry sandstone experiences four stages of initial deformation, constant velocity deformation, accelerated deformation, and instability failure, and that of the water-bearing sandstone experiences three stages of initial deformation, constant velocity deformation, and instability failure. With the increase of water content, the peak axial strain in the corresponding stage gradually decreases. It is verified by the deformation rate analysis method that water has no effect on the deformation memory characteristics of sandstone. Under uniaxial cyclic loading condition, the failure mode of sandstone gradually transits from tension−splitting failure at dryness to tension−shear mixed failure, and presents a single shear failure at saturation. SEM results show that with the increase of water content, the fracture structure plane gradually transits from smooth structure, round structure, and sheet structure to completely broken structure. With the increase of water content, the absolute damage parameter increases, which reflects the positive correlation of water−rock coupling damage, and the cumulative damage parameter larger at the same cycle accumulates faster.

In recent years, with the rapid development of economy, China’s labor relations are constantly changing, and the demands of workers for interests are increasing. In addition, with the outbreak of COVID-19, enterprises are facing severe challenges under both external and internal pressure. In view of this, relying on AI technology and professional personnel, Wish Magic provides consultation and service of labor laws and regulations for people or enterprises in need of relevant help, mediates labor disputes and strives for legitimate interests through online AI keyword search and offline VIP face-to-face expert consultation.

Exploring labor rights on the cognition of relationship with labor dispute is not only from the direct role of workers and HR, but also from the fight for labor rights of college students. However, many labor disputes in labor process are mainly related to labor rights. Therefore, we explore the relationship between labor rights and labor disputes, use neural network analysis and questionnaire survey method, and execute AI combining with big data analysis tools to collect first-hand data from two aspects of college students, workers in the industry, HR and labor dispatch personnel. Finally, the results show that: (1) there is a negative correlation between social security and labor disputes; (2) there is a negative correlation between labor safety and labor disputes; (3) there is a negative correlation between wages and labor disputes; (4) there is a negative correlation between labor contract signing and labor disputes; (5) there is a positive correlation between rights awareness and labor disputes.

Background and Objectives Materials and Methods Results Conclusion An extra health screening, including glycated haemoglobin (HbA1c), total cholesterol (TC) and low‐density lipoprotein cholesterol (LDL‐C), was initiated for regular donors aged over 40 in Taiwan in November 2015. This study aimed to determine its benefits on donor health management and retention.A stratified random mail survey was conducted among donors who received HbA1c, TC and LDL‐C screening between November 2015 and June 2017 to investigate their awareness of the screening, medical histories and post‐screening behaviours. Their subsequent screening results and donation records from 3 years before and after the initial screening were obtained up to December 2021.In total, 2070 donors participated in the mail survey, with participation rates ranging 15.7%–23.2% across study groups. The screening newly detected hyperglycaemia in 1.6% (95% confidence interval [CI]: 1.2%–2.0%) and hyperlipidaemia in 1.0% (95% CI: 0.7%–1.4%) of participants, with 42.7% (95% CI: 40.3%–45.2%) of participants unaware of the screening. Participants with initially abnormal or borderline TC or LDL‐C results showed significant decreases in the subsequent screening (all p values<0.05). No difference was found in participants' awareness of the screening. However, those who sought medical consultation or made specific lifestyle changes tended to show greater improvements. Awareness of the screening was associated with increased whole blood donations and donated units.The extra health screening has limited benefits for donor health management without additional interventions, but it may motivate donors to donate more frequently. Raising donors' awareness of the screening is also crucial to maximize its benefits. [ABSTRACT FROM AUTHOR]

Herein, we present a unified chemical synthesis of three subgroups of cephalotaxus diterpenoids. Key to the success lies in adopting a synthetic strategy that is inspired by biosynthesis but is opposite in nature. By employing selective one‐carbon introduction and ring expansion operations, we have successfully converted cephalotane‐type C18 dinorditerpenoids (using cephanolide B as a starting material) into troponoid‐type C19 norditerpenoids and intact cephalotane‐type C20 diterpenoids. This synthetic approach has enabled us to synthesize cephinoid H, 13‐oxo‐cephinoid H, 7‐oxo‐cephinoid H, fortalpinoid C, 7‐epi‐fortalpinoid C, cephanolide E, and 13‐epi‐cephanolide E. Furthermore, through the development of an intermolecular asymmetric Michael reaction between β‐oxo esters and β‐substituted enones, we have achieved the enantioselective synthesis of advanced intermediates within our synthetic sequence, thus formally realizing the asymmetric total synthesis of the cephalotaxus diterpenoids family. [ABSTRACT FROM AUTHOR]

Long‐term atmospheric water vapour hydrogen (δ2H), oxygen (δ18O) and deuterium excess (d‐excess) can provide unique insights into the land‐atmosphere coupling processes. The in‐situ measurements of atmospheric water vapour δ2H, δ18O and d‐excess were conducted above a reed wetland of Liaodong Bay (2019–2020). We found significant inter‐annual variations in atmospheric water vapour isotopes between the two growing (May–September) seasons. The δ2H, δ18O and d‐excess of atmospheric water vapour exhibited different seasonal and diurnal cycles concerning the vertical measurement heights, especially in 2019. The isotopic differences of atmospheric water vapour among vertical measurement heights were more evident in the daytime. Rainfall events directly impacted the diurnal patterns of water vapour isotopes, and the influences depended on rainfall intensities. However, only weak correlations existed between water vapour isotopes and local meteorological factors (R2 = 0.01–0.16, p < 0.001), such as water vapour concentration (w), Relative Humidity (RH) and surface air temperature (Ta). Based on the back‐air trajectory analyses, the spatial–temporal dynamics of atmospheric water vapour isotopes are highly synchronized with monsoon activities. Different water vapour sources influence the water vapour isotope in this region and the higher d‐excess value is related to the intense convection brought by the monsoon. High‐resolution measurements of atmospheric water vapour isotopes will improve our understanding of the hydrological cycles in coastal areas. [ABSTRACT FROM AUTHOR]