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Pyraclostrobin is one of the most prevalent strobilurin fungicides from the broad-spectrum control of fungal diseases. The ever-increasing pesticides with the active ingredient of pyraclostrobin have been put into the agroecosystem in recent years. The survival of non-targeted organisms and the by-effects on human health can be induced by pyraclostrobin biomagnification within the food web. This study aims to elaborate on the fate characteristics and risk magnitude of pyraclostrobin after large-scale application that contributed to agroecosystem sustainability and dietary rationality. The registered crops included wheat, peanut, watermelon, and cucumber in the main production areas in China. The tracing of pyraclostrobin was performed on the multiple crop matrices using the self-developed ultra-performance liquid chromatographytandem mass spectrometry (UPLC-MS/MS). Some measurements were used to validate the specificity, linearity, matrix effect (ME), accuracy, precision, limit of detection (LOD), and limit of quantification (LOQ). LOD and LOQ were estimated to be 0.000 1 -0.000 4, and 0.001 mg/kg for the wheat grains, wheat straw, peanut kernels, peanut straw, cucumber, and watermelon matrices, respectively. The average recoveries of the target analyte ranged from 81.2% to 112.2% for all fortification levels. The precision values were associated with the analytical methods. The relative standard deviations (RSD) were 0.7% to 18.1% for the pyraclostrobin in all matrices. The fate characteristics of pyraclostrobin were elucidated using the verified storage stability. Some parameters were selected to represent the occurrence, pharmacokinetics dissipation, and terminal magnitude of pyraclostrobin, including the original depositions, half-lives, and terminal magnitude. The concentrations of pyraclostrobin were attached the maximum of <0.001, ≤0.209, ≤0.048 mg/kg 2 h after the last application in peanut kernels, cucumber and watermelon, respectively, and 0.005-0.043 mg/kg 7 d after last application in the wheat grain. Significant differences were observed in the degradation dynamics of pyraclostrobin among different crops, with T1/2 values of 1.9-4.7 d in watermelon, 2.6- 7.5 d in cucumber, and 5.9-9.9 d in wheat grain. There was no T1/2 value of peanut kernels without detecting the pyraclostrobin in any samples. The terminal level of pyraclostrobin in the wheat and peanut straws (0.187-75.291 mg/kg) was much higher than that in the edible part, including the wheat grain and peanut kernel (≤0.096 mg/kg). The long-term dietary risks of pyraclostrobin were further clarified for the population with the different regions, gender, and age using the supervised trials median residues (STMR) for the investigated crops that were recommended by the large-scale field trials. The risk quotients (RQ) were assessed as 123.959%-406.415% by the deterministic model, indicating out of the acceptable range. The risk quotients were inversely correlated to the age of the population. The children group was subjected to the greatest long-term risks of pyraclostrobin exposure from the dietary pathway. The population subgroup location in rural (RQ, 146.799%- 406.415%) suffered more serious exposures than that in urban (123.959%-374.217%). A probabilistic model was further introduced for a more accurate estimation of dietary exposure. The total chronic risks (RQ) caused by consuming wheat grain and watermelon ranged from 0.025% to 11.309% from the 50 percentile to the 99.9 percentile, far less than 100%, indicating no potential risks for the population. The unacceptable chronic risk magnitude of pyraclostrobin was determined, according to the probabilistic distribution in the residual levels of the above four crops. Anyway, the hazard effects of pyraclostrobin from dietary pathways should be emphasized in daily life, especially for rural children group. [ABSTRACT FROM AUTHOR]

Objective: To explore the relation of fear of missing out to social network site use and self-esteem in the college students. Methods: Totally 732 college students in Shandong Province were selected and tested with the Fear of Missing Out scale ( FoMOs), Social Network Site Intensity Scale ( SNSIS), and Self-Esteem Scale (SES). Results: The scores of FoMOs and SN SIS were higher in the urban college students than in the rural college students ( Ps < 0. 05). Regression analysis showed that after controlling the place of residence and grade, the interaction between social network site use and self-esteem negatively predicted the fear of missing out of college students ({3 = - 0. 02, P <0. 001) . A simple slope analysis showed that high self-esteem individuals ( B = 0. 22) could alleviate social network site use of fear of missing out, while low self-esteem individuals ( B = 0. 38) could improve the fear of missing out level in the use of social network site. Conclusion: It suggests that self-esteem may moderate the relationship between social network site use and fear of missing out in college students. [ABSTRACT FROM AUTHOR]

The excellent mechanical properties of grout sleeve is the key to ensure the integrity of the prefabricated structure. Combined with the bond-slip theory, the influence of the depth of the grout rib on the mechanical properties was studied in the new type grout sleeve by analyzing the parameters of the axial stress of the sleeve rib depth, the Mises stress of each rib, minor principal stress of the grout material and the ultimate stress of the sleeve. The results show that there is obvious correspondence between the depth of sleeve rib and its limit stress, the depth of sleeve rib increases, and the sleeve limit stress gradually increases. There is obvious correspondence between the sleeve convex rib depth and the displacement, the sleeve convex rib depth increases, the displacement change is slow, but the overall displacement difference is generally consistent. and there is obvious correspondence between the depth of the sleeve convex rib and minor principal stress of the grout material, the increase of the internal convex rib depth is beneficial to improve the overall mechanical properties of the grouting sleeve within a certain range of rib depth, however, when the depth of the convex ribs exceeds a certain range, the bearing capacity of the specimen decreases. [ABSTRACT FROM AUTHOR]