There are limited studies on the relation between short-term exposure to air pollutants and the risk of deep venous thrombosis (DVT). The aim of this study was to determine the relation between the concentration of these pollutants and the risk of hospital admissions due to DVT in Ahvaz, which is one of the world's highly polluted cities. Daily data on pollutants including O 3 , NO, NO 2 , SO 2 , CO, PM 10 , and PM 2.5 and DVT hospital admissions were collected from2008until 2018. Quasi-Poisson regression combined with linear distributed lag models; adjusted for trend, seasonality, temperature, relative humidity, weekdays, and holidays were used to assess the relation between the daily average of air pollutants and hospital admission for DVT. The results showed that there was a significant increase in hospital admissions due to DVT in the total, men, women, and elderly populations in relation to NO and NO 2. There was also a significant increase in DVT hospital admissions in the male and 60 years populations related to PM 10 ; and among the female and 60 years old populations, related to PM 2.5. Finally, the results showed that there were significant positive associations between SO2 and CO exposure and the incidence of DVT hospital admissions among men and women, respectively. The results of this study show the possible effect of short-term exposure to air pollution on the risk of DVT. Further studies are required to investigate whether direct interventions through industry and government policy may alter the impact of specific pollutants in order to alter the incidence of DVT and other identified health complications.

Medical grand rounds as a key teaching exercise originating from the bedside rounds conducted by prominent clinicians. Traditional (face-to-face) Ground Rounds have been robust in medical education that can update students 'information and help students' clinical decisions in treating their patients. Due to the Coronavirus Disease of 2019 (COVID-19) pandemic and its effects on different aspects of life, including education, most medical universities have begun to use online education as a new way to provide medical education, and online classes have become one of the common teaching methods. Virtual Grand Round sessions were implemented to facilitate continuity of care. Implementing virtual grand rounds during the pandemic period and considering the results and effectiveness from the perspective of students as direct benefactors can provide a good understanding of the potential of this method of e-learning. This article provides an overview of which medical disciplines have used the virtual Grand Round program for education during the COVID-19 pandemic and what are the benefits and results.