In this study, the free electron laser (FEL) with a planar wiggler and an ion-channel in a rectangular waveguide is studied for TE waves with numerical simulation. The output power of FEL is obtained self-consistently from the equation of motion and Maxwell's equations. Numerical analysis shows that using the ion-channel, in spite of the magnetic field case [Sakamoto et al., J. Appl. Phys. 75, 36 (1994)], can improve output power in addition to guiding the electrons into the center and prevent dissipation of the beam.

Objective: How people use social rank (dominance vs prestige) could explain different attitudes toward five moral foundations. This study aimed to investigate the differential relationships between prestige, dominance, and moral foundations. Methods: This study was conducted on 150 participants who responded to the moral foundation questionnaire and dominance-prestige scale. Results: Multiple regression analysis revealed that prestige was positively associated with four kinds of moral foundations (harm/care, reciprocity/fairness, loyalty/subversion, and purity/sanctity), whereas dominance was negatively associated with harm/care, reciprocity/fairness, and progressivism. Prestige had a stronger association with moral foundations than dominance. Conclusion: It seems that dominance as a social status seeking-strategy is against any moral foundation, but prestige could increase attention to moral foundations in decision making toward every life issue.

The COVID-19 outbreak is a new potentially traumatic event that may have some unknown effects on mental health. The aim of this study was to examine how two theoretical frameworks related to coping with trauma, including shattered assumptions and coping with trauma, could explain mental health and acute stress symptoms among the general population during the COVID-19 outbreak. The participants included 212 Iranian Muslims who filled out the online survey. Women and people with non-fixed jobs reported more mental health deterioration and acute stress symptoms. There were no significant differences between people with or without COVID-19 in terms of mental health symptoms, experiencing acute stress symptoms, and world assumptions. Results showed that world assumption and forward-focused coping could predict mental health symptoms and acute stress symptoms beyond COVID-19 specific stress. Assumptions related to the meaningfulness of the world and trauma-focused coping were associated with a higher score in general mental health symptoms and acute stress, but assumptions related to the benevolence of the world, self-worth, and forward-focused coping were associated with lower mental health and acute stress symptoms. This could suggest that world assumptions could buffer or endanger mental health during crises such as the pandemic. In addition, it seems that forward-focus coping is effective for managing new life challenges during the COVID-19 outbreak. In contrast, the more people address the negative and catastrophic effects of COVID-19 (such as trauma-focused coping), the more they are prone to developing mental health symptoms. This study showed that among Iranian Muslims, some world assumptions (for example, the meaningfulness of world) and some kinds of coping (for example, trauma-focused coping) were not as protective factor as in non-Muslim countries.

By considering the propagation of TM waves in a rectangular waveguide, the radiated power of a free electron laser is calculated during beam–wave interaction in a planar wiggler. A set of self-consistent equations are derived for discerption of this system which includes some electrostatic and electromagnetic fields, equation of motions and evolution equations of amplitude and phase. The evolution equations of amplitude and phase are determined using an averaging method on the wave equation. By writing a 3D simulation code, the variation in power during electron beam propagation is investigated and then the role of various ion channel density on efficiency is examined. Numerical results show that there is a significant increase in the radiation power of TM waves in comparison with the TE waves in the proposed configuration.