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A finite element simulation model of terahertz wave propagation in plasma is developed. The equivalence of treating the plasma as a dielectric and an electrical conductor is studied in comparison. The propagation characteristics of terahertz waves in a unmagnetized plasma obtained from experimental measurements or simulations are simulated by interpolating the distribution of key parameters such as electron density and collision frequency of the external plasma. The validity of this open simulation model is verified by using the simulation data of plasma electron density generated by the independent electrochemical plasma generation model as external data. Using this model as a research tool, the propagation characteristics of terahertz waves in plasma measured by laser Thomson scattering are studied. The simulation results of the terahertz wave propagation characteristics in the plasma with and without considering the collision frequency are compared by this model. The terahertz transmission model in plasma can be used to study the propagation characteristics of terahertz waves in various inhomogeneous plasmas, which would be helpful to solve the communication "blackout" problem. [ABSTRACT FROM AUTHOR]

Objective: Focusing on the relationship between unpaid labor and the occurrence of depressive symptoms, this study aimed to explore the factors influencing the inequality of depressive symptoms and their contribution among Chinese urban and rural employed people. Methods: This study utilized the 2020 China Family Panel Studies' national resampling data. Multivariate logistic regression was used to explore the factors influencing the occurrence of depressive symptoms among employed persons in urban and rural areas in China, respectively. Fairlie decomposition was used to explore the contribution of influencing factors such as unpaid labor to the difference in the occurrence of depressive symptoms between urban and rural areas. Results: About 2,136 (21.70%) participants had depressive symptoms, of which 1,197 (24.75%) rural employed people had depressive symptoms and 939 (18.75%) urban employed people had depressive symptoms. The results of Fairlie decomposition analysis showed that 70.51% of the differences in depressive symptoms between urban and rural Chinese employed people could be explained by the covariates included in this study, including education level (52.44%), age (−11.91%), housework time (10.42%), self-rated health status (10.22%), self-rated income status (2.53%), exercise (2.36%), job satisfaction status (1.99%), chronic disease status (1.90%), and marital status (1.79%). Conclusion: This study found that the proportion of depressive symptoms was lower among urban employed residents than among rural employed residents. This difference was mainly caused by unpaid labor time, socioeconomic status, personal lifestyle, and health status. Housework, which is one of the unpaid labor, contributed to this depressive symptom difference in the third place. [ABSTRACT FROM AUTHOR]

Background: Adolescents often carry their depression well into their adulthood. This creates perpetual difficulties for their family and society. Research on the relationship between positive parenting and adolescent depressive symptoms is rare. The protective effect of positive parenting on adolescent depressive symptoms also remains underexplored. Parents are a vital source of feedback that shapes adolescents' self-view in crucial ways. Aims: This study examines the latent relationships between four factors related to positive parenting and adolescent depressive symptoms. Method: Using data from the Chinese Family Panel Studies (CFPS), Stata MP 17.0 was used for preliminary data processing and descriptive statistics. The structural equation model (SEM) was adopted to test the seven proposed hypotheses. Results: The study participants were 2,816 adolescents (52.34% male). The SEM showed that positive communication and parental praise can directly reduce depressive symptoms in adolescents (path coefficients of −0.24 and −0.13 [ p <.001], respectively). Additionally, both positive communication and positive parent-adolescent interactions can reduce adolescents' depressive symptoms by heightening the intermediate factor of parental praise (path coefficients of 0.30 and 0.44 [ p <.001], respectively). Conversely, positive parent-adolescent interactions did not negatively affect adolescents' depressive symptoms, as we hypothesized. Conclusions: High level of positive parenting negatively predicts the level of depressive symptoms among adolescents. Specifically, positive communication, positive parent-adolescent communication, and parental praise are the main protective factors related to positive parenting for adolescents' depressive symptoms. [ABSTRACT FROM AUTHOR]

High-order spoof surface plasmon (SSP) mode on corrugated metallic surfaces can find many interesting applications, such as in imaging, sensing, transmission and enhanced radiation source, etc. In this paper, an efficient excitation method of the high-order SSP mode by using an injected electron beam on the uniform rectangular metallic grating is proposed and investigated numerically. Based on the matched wave momentum between the SSP mode and the electron beam, both the fundamental and high-order SSP modes can be excited on the structure by using a single injected electron beam. Numerical simulation results indicate that the maximum electric field intensity of the generated high-order SSP mode is about two orders higher than that of the fundamental SSP mode. In addition, the peak power of the excited high-order SSP mode is almost two times that of the fundamental SSP mode power by the same energy electron beam, which demonstrates the obvious advantage of the high-order SSP electronic excitation approach compared to the previous fundamental SSP mode excitation on the structure. The central working frequency of high-order SSP power spectrum is about three times that of the fundamental SSP power spectrum. Moreover, the influences of the injected electron beam energy on the excited SSP power spectrum are analyzed specifically. It is shown that the generated SSP power spectrum demonstrates a blue shift with the decreased working voltage of the electron beam simultaneously, with its peak power increasing. However, the working bandwidth is narrowed with decreased beam voltage, which further reveals its working mechanism of presented electronic excitation of the SSP mode. The presented studies provide a new method to excite a high-order SSP mode on the metallic grating, which can find some potential applications in high-sensitivity sensing, deep sub-wavelength waveguide, and many others in terahertz spectra. [ABSTRACT FROM AUTHOR]