Aim: To assess the association between personality traits by the five-factor model and specialty choice preference among medical students and immediate medical graduates in Jordan and to identify if there were any significant differences in personality profiles between those planning to pursue different career pathways. Methods: This is a cross-sectional study including fifth- and sixth-year medical students and post-graduate internship doctors at five universities in Jordan. An online survey was used to collect data from participants, which included their general characteristics, their personality profile using the Big Five Inventory– 2, and questions about their most preferred specialty choice. Results: One thousand and twelve participants were enrolled in this study. Only 4.9% were interested in pursuing a specialty in basic medical sciences, and about 12% wanted to be non-practicing medical doctors. Almost half of all participants wanted to pursue a career in surgery-oriented specialties. Those were more extraverted, more conscientious, and had less negative emotions than students who chose medicine-oriented specialties. Students who decided to pursue clinical specialties and students who wanted to be practicing doctors were more extraverted and more conscientious. Conclusion: Medical students and fresh medical graduates from Jordan who exhibited higher extraversion and conscientiousness and lower negative emotions preferred to be practicing clinicians. They were more inclined to pursue a career in surgery-oriented specialties. These findings might be helpful in understanding the preferences of young doctors and in counseling them about their career paths. Medical educators may wish to incorporate personality trait evaluation in planning post-graduate programs.

Background. Waterpipe nicotine dependence and its association with depressive symptoms and dual usage among adolescents are currently not examined in the literature. Adolescents are a vulnerable population that is susceptible to depression and initiation of tobacco use. We aim, in this novel study, to assess the association between depressive symptoms and waterpipe nicotine dependence among adolescents in Jordan, evaluate the association between waterpipe smoking status (waterpipe smoker vs. dual user) and waterpipe nicotine dependence, and assess the internal validity of the Waterpipe Nicotine Dependence Scale (WNDS). Method. A cross-sectional study among adolescents of grade 9^th to 12^th in Jordan was conducted through multistage cluster random sampling. The self-reported Arabic Youth Tobacco Use Composite Measure Questionnaire (YTUCM) was used to collect the surveys that include demographic information, smoking status, and the WNDS to assess waterpipe nicotine dependence and depressive symptoms. Multiple linear regression and the t-test were used to analyze the data. Findings. One thousand three hundred and three surveys were collected, of which 1082 were included in the study (443 males and 639 females). 64.9 of the sample were nontobacco users, while 20.1 were waterpipe- (WTP-) only smokers, 11.4 were dual users, and 3.7 were cigarettes-only users. After adjusting for weights, 66.6 were nonsmokers, 19.2 were WTP-only smokers, 10.2 were dual users, and 3.9 were cigarettes-only smokers. Using multiple linear regression, depressive symptoms were significantly associated with WTP nicotine dependence (β 0.618), upon adjusting for confounders. Furthermore, dual users were associated with higher WTP nicotine dependence (β 12.034) compared to WTP-only smokers after adjusting for confounders. Cronbachs alpha for the WNDS was 0.955. Conclusions. Our study shows that there is a statistically significant association between depressive symptoms and WTP nicotine dependence and higher dependence among dual users compared to WTP-only smokers. The WNDS can be a useful tool to assess WTP nicotine dependence with high internal consistency. However, a longitudinal study is needed to further understand the association and temporality between the depressive symptoms and WTP nicotine dependence. Additionally, research is needed to shorten the WNDS while maintaining high internal consistency and assess the external validity of the WNDS and the short- and long-term consequences of dual usage.

Lithium imposes several cellular effects allegedly through multiple physiological mechanisms. Membrane depolarization is a potential unifying concept of these mechanisms. Multiple inherent imperfections of classical electrophysiology limit its ability to fully explain the depolarizing effect of lithium ions; these include incapacity to explain the high resting permeability of lithium ions, the degree of depolarization with extracellular lithium concentration, depolarization at low therapeutic concentration, or the differences between the two lithium isotopes Li-6 and Li-7 in terms of depolarization. In this study, we implemented a mathematical model that explains the quantum tunneling of lithium ions through the closed gates of voltage-gated sodium channels as a conclusive approach that decodes the depolarizing action of lithium. Additionally, we compared our model to the classical model available and reported the differences. Our results showed that lithium can achieve high quantum membrane conductance at the resting state, which leads to significant depolarization. The quantum model infers that quantum membrane conductance of lithium ions emerges from quantum tunneling of lithium through the closed gates of sodium channels. It also differentiates between the two lithium isotopes (Li-6 and Li-7) in terms of depolarization compared with the previous classical model. Moreover, our study listed many examples of the cellular effects of lithium and membrane depolarization to show similarity and consistency with model predictions. In conclusion, the study suggests that lithium mediates its multiple cellular effects through membrane depolarization, and this can be comprehensively explained by the quantum tunneling model of lithium ions.