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Parental psychological control is strongly associated with adolescents' drinking. We used self-determination theory as a conceptual framework for testing the mediating effect of academic efficacy in the association between parental psychological control and adolescent drinking behavior, and the moderating effects of teacher-student relationship and sensation seeking in this indirect process. Moreover, we tested the above model in boys and girls separately to test gender differences. A total of 1,007 junior middle school students (Mean age = 13.16 years, SD = 0.67 years, 48.2% male) in south China completed questionnaires in their classrooms. We conducted a path analysis in Mplus 8.0 to test our moderated mediation model. The results showed that: (1) the influence of parental psychological control on drinking behavior was only significant among girls; (2) academic self-efficacy significantly mediated the relationship between parental psychological control and girls' drinking behavior; (3) the first and second parts of the mediating pathways were moderated by teacher-student relationship and sensation seeking, respectively. The current findings highlight the need to address individual, family, and school factors in prevention and intervention programs for girls' drinking in adolescence., Author(s): Zhenhai Wang [sup.1] , Chengfu Yu [sup.2] , Zhiyuan Tao [sup.1] , Yanrong Chen [sup.1] , Yanhan Chen [sup.1] , Wei Zhang [sup.1] Author Affiliations: (1) https://ror.org/01kq0pv72, grid.263785.d, 0000 [...]

In recent years, adolescent sleep problems have received increasing attention. Stressful life events have been found to be a risk factor for sleep problems, but little is known about the components that may explain or influence this association. To investigate this, the present study tested whether depressive symptoms mediated the association between stressful life events and Chinese freshmen' sleep problems, as well as whether emotional regulation skills moderated this process. A sample of 513 Chinese freshmen (32.2% males, mean age = 19.04 years, SD = 1.21) completed anonymous questionnaires regarding stressful life events, depressive symptoms, emotional regulation and sleep problems (examined using Adolescent Self-Rating Life Events Checklist, Epidemiologic Studies Depression Scale for Children, Pittsburgh Sleep Quality Index and Response to Stress Questionnaire). The study included covariates such as gender, age, and socioeconomic level. Depressive symptoms were shown to partially mediated the association between stressful life events and sleep problems in structural equation models. Emotional regulation moderated the relationship betweenn stressful life events and depressive symptoms. The results show that promoting emotional regulation could be beneficial in preventing and intervening sleep problems related to stressful life events.

The heat-aging process, a practical aging technology that not only improves the comprehensive performance of Al alloys but also reflects the requirements of short processes, has an extremely practical significance. The effects of the heating rate and termination temperature on the "heat-aging" behavior of a spray-deposited AlZnMgCu alloy hot-extruded plate were investigated using hardness, electrical conductivity, room-temperature tensile strength, exfoliation corrosion experiments, and transmission electron microscopy microstructure (TEM) observation. The results show that as the termination temperature increases, the hardness of the spray-deposited AlZnMgCu alloy first increases to a peak and then rapidly decreases, while the electrical conductivity continues to increase. The increase in the heating rate improves the peak hardness corresponding to the termination temperature. The heat treatment process of heating at a speed of 20 °C/h to 200 °C after the spray deposition has similar mechanical and corrosion resistance properties to the RRA process and can effectively reduce the heating time from 40 h to 8 h, thus establishing a heat treatment process for spray-deposited AlZnMgCu alloy extruded plate with high aging efficiency. [ABSTRACT FROM AUTHOR]

In recent years, adolescent sleep problems have received increasing attention. Stressful life events have been found to be a risk factor for sleep problems, but little is known about the components that may explain or influence this association. To investigate this, the present study tested whether depressive symptoms mediated the association between stressful life events and Chinese freshmen' sleep problems, as well as whether emotional regulation skills moderated this process. A sample of 513 Chinese freshmen (32.2% males, mean age = 19.04 years, SD = 1.21) completed anonymous questionnaires regarding stressful life events, depressive symptoms, emotional regulation and sleep problems (examined using Adolescent Self‐Rating Life Events Checklist, Epidemiologic Studies Depression Scale for Children, Pittsburgh Sleep Quality Index and Response to Stress Questionnaire). The study included covariates such as gender, age, and socioeconomic level. Depressive symptoms were shown to partially mediated the association between stressful life events and sleep problems in structural equation models. Emotional regulation moderated the relationship betweenn stressful life events and depressive symptoms. The results show that promoting emotional regulation could be beneficial in preventing and intervening sleep problems related to stressful life events. Practitioner points: Stressful life events were positively associated with sleep problems among Chinese college freshmen.Depressive symptoms mediated the relationship between stressful life events and sleep problems among Chinese college freshmen.Emotional regulation moderated the relationship between stressful life events and depressive symptoms. [ABSTRACT FROM AUTHOR]

This paper presents a real‐time OFDM‐based visible light communication (VLC) system utilizing a single InGaN/GaN multiquantum‐wells (MQWs) light emitting diode (LED). An MQWs LED with 3 dB electrical bandwidth of 23.8 MHz is developed as the transmitting device. Orthogonal frequency division multiplexing (OFDM) is employed to ensure the LED bandwidth is fully used, and the system is designed and implemented on a field‐programmable gate array platform to realize real‐time communication. The real‐time OFDM‐VLC system achieves a rate of 96 Mbit/s at the distance of 2 m, and the bit error ratio (BER) is 2.25 × 10−3, which is below the forward error correction (FEC) limit. [ABSTRACT FROM AUTHOR]

Condensation and esterification are important catalytic routes in the conversion of polyols and oxygenates derived from biomass to fuels and chemical intermediates. Previous experimental studies show that alkanal, alkanol and hydrogen mixtures equilibrate over Cu/SiO2 and form surface alkoxides and alkanals that subsequently promote condensation and esterification reactions. First-principle density functional theory (DFT) calculations were carried out herein to elucidate the elementary paths and the corresponding energetics for the interconversion of propanal + H2 to propanol and the subsequent C–C and C–O bond formation paths involved in aldol condensation and esterification of these mixtures over model Cu surfaces. Propanal and hydrogen readily equilibrate with propanol via C–H and O–H addition steps to form surface propoxide intermediates and equilibrated propanal/propanol mixtures. Surface propoxides readily form via low energy paths involving a hydrogen addition to the electrophilic carbon center of the carbonyl of propanal or via a proton transfer from an adsorbed propanol to a vicinal propanal. The resulting propoxide withdraws electron density from the surface and behaves as a base catalyzing the activation of propanal and subsequent esterification and condensation reactions. These basic propoxides can readily abstract the acidic Cα–H of propanal to produce the CH3CH(−)CH2O* enolate, thus initiating aldol condensation. The enolate can subsequently react with a second adsorbed propanal to form a C–C bond and a β-alkoxide alkanal intermediate. The β-alkoxide alkanal can subsequently undergo facile hydride transfer to form the 2-formyl-3-pentanone intermediate that decarbonylates to give the 3-pentanone product. Cu is unique in that it rapidly catalyzes the decarbonylation of the C2n intermediates to form C2n−1 3-pentanone as the major product with very small yields of C2n products. This is likely due to the absence of Brønsted acid sites, present on metal oxide catalysts, that rapidly catalyze dehydration of the hemiacetal or hemiacetalate over decarbonylation. The basic surface propoxide that forms on Cu can also attack the carbonyl of a surface propanal to form propyl propionate. Theoretical results indicate that the rates for both aldol condensation and esterification are controlled by reactions between surface propoxide and propanal intermediates. In the condensation reaction, the alkoxide abstracts the weakly acidic hydrogen of the Cα–H of the adsorbed alkanal to form the surface enolate whereas in the esterification reaction the alkoxide nucleophilically attacks the carbonyl group of a vicinal bound alkanal. As both condensation and esterification involve reactions between the same two species in the rate-limiting step, they result in the same rate expression which is consistent with experimental results. The theoretical results indicate that the barriers between condensation and esterification are within 3 kJ mol−1 of one another with esterification being slightly more favored. Experimental results also report small differences in the activation barriers but suggest that condensation is slightly preferred. [ABSTRACT FROM AUTHOR]