Résumé
The global outbreak of coronavirus disease 2019 (COVID-19) has affected the urban mobility of nations around the world. The pandemic may even have a potentially lasting impact on travel behaviors during the post-pandemic stage. China has basically stopped the spread of COVID-19 and reopened the economy, providing an unprecedented environment for investigating post-pandemic travel behaviors. This study conducts multiple investigations to show the changes in travel behaviors in the post-pandemic stage, on the basis of empirical travel data in a variety of cities in China. Specifically, this study demonstrates the changes in road network travel speed in 57 case cities and the changes in subway ridership in 26 case cities. Comprehensive comparisons can indicate the potential modal share in the post-pandemic stage. Further, this study conducts a case analysis of Beijing, where the city has experienced two waves of COVID-19. The variations in travel speed in the road network of Beijing at different stages of the pandemic help reveal the public's responses towards the varying severity of the pandemic. Finally, a case study of the Yuhang district in Hangzhou is conducted to demonstrate the changes in traffic volume and vehicle travel distance amid the post-pandemic stage based on license plate recognition data. Results indicate a decline in subway trips in the post-pandemic stage among case cities. The vehicular traffic in cities with subways has recovered in peak hours on weekdays and has been even more congested than the pre-pandemic levels;whereas the vehicular traffic in cities without subways has not rebounded to pre-pandemic levels. This situation implies a potential modal shift from public transportation to private vehicular travel modes. Results also indicate that commuting traffic is sensitive to the severity of the pandemic. This may be because countermeasures, e.g., work-from-home and suspension of non-essential businesses, will be implemented if the pandemic restarts. The travel speed in non-peak hours and on non-workdays is higher than pre-pandemic levels, indicating that non-essential travel demand may be reduced and the public's vigilance towards the pandemic may continue to the post-pandemic stage. These findings can help improve policymaking strategies in the post-pandemic new normal. © 2023 American Society of Civil Engineers.
Résumé
Due to the coronavirus pandemic, portable electrical impedance tomography (EIT) systems [1]-[3] have been considered as the only variable wearable medical lung imaging solution for monitoring the treatment of pneumonia patients and their recovery. Generally, the EIT system is classified into passive EIT (P-EIT) [3]-[6] or active electrode EIT (AE-EIT) [2]. The AE-EIT system is preferred as it amplifies and digitalizes the small signals while minimizing the noises incurred by motion artifacts, complex long wire connection, large variation in electrode contact, and stray capacitance problems, which is important for high-performance imaging applications. © 2022 IEEE.
Résumé
This study aimed to describe the clinical characteristics and prognosis of COVID-19 patients who received tracheal intubation and mechanical ventilation. A total of 52 critical COVID-19 patients who received tracheal intubation were retrospectively included. The primary data including clinical features, laboratory results, and the outcomes were collected and analyzed. Among the 52 patients who received tracheal intubation, 14 were successfully extubated within two weeks and 38 failed extubation. The patients in the extubation failure group were significantly older than the patients in the successful extubation group (median age, 67.50 years vs 55.50 years). The median values of SpO2 and the PaO2/FiO2 (P/F) before tracheal intubation were significantly lower in extubation failure group than the those in successful extubation group (SpO2: 78.50% vs 85%, P/F: 71.50 mmHg vs 84.50 mmHg). Compared with the successful extubation group, the extubation failure group was found to have a significantly lower 28-day survival rate (21.05% vs 100%). Patients with extubation failure had more severe multi-organ injuries. Besides, a more severe hypoxia level was found to be associated with the failure of extubation and subsequent poor prognosis. Therefore, tracheal intubation and timely invasive mechanical ventilation should be administered in COVID-19 patients with refractory hypoxemia.