Longitudinal change in symptoms of depression, anxiety and post-traumatic stress disorder during the COVID-19 pandemic among Mexican college students.

Longitudinal studies suggest the psychological difficulties precipitated by the COVID-19 pandemic have gradually declined, but our understanding of the factors that predict change in mental health is limited. We evaluated the mental health of Mexican college students during the early stage of the pandemic and 4 months later, as well as predictors of change in students' mental health. Participants were 648 students (71% women, Mage = 21.46) from a private University in Northern Mexico who completed online surveys from May 2020 to September 2020. Students' self-reported levels of mental health symptoms (depression, anxiety and post-traumatic stress disorder) significantly decreased from May to September. Poor physical health, more COVID-related worry and higher initial levels of peer social support predicted less change in psychological symptoms. On the other hand, more hours of sleep per night and a pre-existing mental health diagnosis predicted steeper decreases in symptoms. Findings suggest reductions in mental health difficulties that are consistent with theoretical frameworks of resilience among Mexican college students. In addition, results underscore the interplay between physical, psychological and social functioning, and the need for continued monitoring of mental health and intervention efforts that address physical health, sleep and pandemic-related worry in University settings.

COVID-19 related psychosocial problems among university students in Mexico - a longitudinal qualitative examination.

Research on the impact of the COVID-19 pandemic among college students around the world has primarily focused on their mental health symptoms and COVID-specific worry. However, contextually specific understanding of outbreak impacts is key to inform directed public health messaging and programming to improve wellbeing and coping. The current study aimed to identify the main psychosocial problems college students experienced during the first 6 months of the COVID-19 pandemic in Monterrey, Mexico. Participants were 606 college students (71% female) enrolled in a private university. Participants described COVID-related problems in an open-ended prompt as part of a longitudinal online survey: initially in May 2020, and then every 2 weeks for 3 months. Thematic analyses were conducted within a longitudinal inductive qualitative approach to rank responses by frequency across themes. Five major categories emerged. At baseline, over 75% of participants noted the outbreak negatively impacted their daily activities and responsibilities, 73% their mental health, 50% their physical health, 35% their interpersonal relationships, and 22% their economic situation. Concerns remained relatively stable throughout the follow-up period, with interpersonal and economic concerns becoming more prevalent as the pandemic progressed. Problems identified in this study can inform preventative measures for future health crises, including tailoring public health messaging and expanding access to contextually sensitive mental and behavioral health programming.

Spectral characteristics and photosensitization of TiO2 nanoparticles in reverse micelles by perylenes.

We report on the photosensitization of titanium dioxide nanoparticles (TiO2 NPs) synthesized inside AOT (bis(2-ethylhexyl) sulfosuccinate sodium salt) reverse micelles following photoexcitation of perylene derivatives with dicarboxylate anchoring groups. The dyes, 1,7-dibromoperylene-3,4,9,10-tetracarboxy dianhydride (1), 1,7-dipyrrolidinylperylene-3,4,9,10-tetracarboxy dianhydride (2), and 1,7-bis(4-tert-butylphenyloxy)perylene-3,4,9,10-tetracarboxy dianhydride (3), have considerably different driving forces for photoinduced electron injection into the TiO2 conduction band, as estimated by electrochemical measurements and quantum mechanical calculations. Fluorescence anisotropy measurements indicate that dyes 1 and 2 are preferentially solubilized in the micellar structure, creating a relatively large local concentration that favors the attachment of the dye to the TiO2 surface. The binding process was followed by monitoring the hypsochromic shift of the dye absorption spectra over time for 1 and 2. Photoinduced electron transfer from the singlet excited state of 1 and 2 to the TiO2 conduction band (CB) is indicated by emission quenching of the TiO2-bound form of the dyes and confirmed by transient absorption measurements of the radical cation of the dyes and free carriers (injected electrons) in the TiO2 semiconductor. Steady state and transient spectroscopy indicate that dye 3 does not bind to the TiO2 NPs and does not photosensitize the semiconductor. This observation was rationalized as a consequence of the bulky t-butylphenyloxy groups which create a strong steric impediment for deep access of the dye within the micelle structure to reach the semiconductor oxide surface.