This study analyzes the contents of 115 articles related to the risk of tourism diseases to investigate research development trends from the period after the outbreak of severe acute respiratory syndrome to early 2020. The main findings show that researchers lack attention to the risk posed by tourism-related diseases, and research on these diseases is often synchronized with the occurrence of major international diseases and the development trends in tourism. Additionally, diseases are related to tourism, and they can interact with each other; research on disease risk management lacks a theoretical basis and the research themes are uneven.

Objective: To investigate dopamine transmission in patients with comorbid REM sleep behavior disorder (RBD) and major depressive disorder (MDD). Methods: This is a case-control study including 11 medicated patients with comorbid RBD and MDD (mean age 47.5 ± 8.2), 8 medicated patients with MDD only (mean age 47.9 ± 8.4), and 10 healthy participants (mean age 46.5 ± 10.6 years). They underwent clinical assessment, video-polysomnography, olfactory tests, and neuroimaging studies (¹⁸F-DOPA, ¹¹C-raclopride, and ¹⁸F-FDG PET neuroimaging). Results: Compared with the 2 control groups, patients with comorbid RBD and MDD had significantly lower ¹⁸F-DOPA uptake at 60 minutes in the putamen and caudate after controlling for age and sex effect (p < 0.05). There were no significant differences for the ¹¹C-raclopride and ¹⁸F-FDG-PET. The ¹⁸F-DOPA uptake in putamens had significant inverse correlation with severity of RBD symptoms (p < 0.01) and REM-related tonic muscle activity (p < 0.01). The comorbid RBD and MDD group had more impairment in olfactory function. Conclusion: Patients with comorbid RBD and MDD had presynaptic dopamine dysfunction and impaired olfactory function. There is a distinct possibility that the development of RBD symptoms among patients with MDD may represent an early phase of α-synucleinopathy neurodegeneration instead of a merely antidepressant-induced condition.

With the advent of the fifth-generation mobile communication technology era, mobile technology will further change tourism. However, studies on mobile technology in tourism from the perspective of bibliometrics and visualization are limited. This research aimed to systematically, comprehensively, and objectively analyze the current research status and potential future research directions in this field through a visual bibliometric analysis of mobile technology research in tourism. This study used CiteSpace software to analyze 803 related journal papers from the Web of Science Core Collection and provided insights into the research of mobile technology in tourism from the aspects of research trends, research areas, top journals, author/institution/country or region collaboration networks, research keywords, and research foundations. The study can help related personnel in academia and industry to fully understand the research of mobile technology in tourism and provides valuable references for related research fields on bibliometric and visualized analysis.