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Ammonia (NH 3) is a vital precursor of secondary aerosols, which play an important role in urban air pollution. The passive observation of NH 3 in the urban atmosphere showed higher concentrations than conventionally believed; however, the NH 3 dynamics remain limited due to the paucity of active measurements with fast response instruments. In this study, intensive online measurements of ambient NH 3 were conducted using cavity ring-down spectroscopy in late spring and early summer 2020 at the megacities of Beijing and Shanghai in northern and southern China. The results show that the average NH 3 concentration in Beijing (23.1 ± 10.3 ppb) was nearly double that in Shanghai (12.0 ± 5.0 ppb). This spatial difference was confirmed by satellite column observations and bottom-up emission patterns. In addition, there was a significant increase in NH 3 concentrations during the morning in our study. This special diurnal profile was a universal feature, with an occurrence frequency exceeding 50% in both cities. These frequent morning increases were mainly caused by motor vehicle emissions, with an additional contribution from the residual layer breakup for one-quarter of the days in the morning increase. On these days, the NH 3 concentration increased by approximately 20% due to the downward mixing of the residual layer rupture. The unique data observed here could be used to validate the chemistry and transport models at a higher time resolution and improve the understanding of the current status of NH 3 pollution in the urban atmosphere. [Display omitted] • 1 Hz NH 3 observations were conducted at megacities of Beijing and Shanghai. • Atmospheric NH 3 concentrations in urban Beijing were double that in Shanghai. • A morning pulse of NH 3 levels was a common feature at Beijing and Shanghai. • Highly frequent morning increases of NH 3 were mainly caused by vehicle emissions. • Boundary layer rupture further enhanced the rapid increase of NH 3 in the morning. [ABSTRACT FROM AUTHOR]

Prior literature finds senior executives can influence auditor decision making. However, few studies have discussed the impact of employee's personal characteristics. Our research aims to fill the above research gaps by examining the impact of employee level education on audit costs. Taking A-share listed companies in Shanghai and Shenzhen from 2006 to 2021 as the research object, this paper examines the impact of employee education on audit fees. It is found that highly educated employees can effectively reduce the audit fees borne by the company, but the implementation of the Labor Protection Law weakens this inhibitory effect. In the case of low marketization level and weak Confucian culture intensity, employee education level has a more significant inhibitory effect on audit fees of listed companies. This study provides a basis for empirical research on the impact of employee attributes on auditor decision making, provides a new research perspective on the impact of labor protection law at the corporate micro level, and enriches the theoretical research on corporate governance rooted in traditional Chinese culture. We contribute to the practice that implications for evaluating the effectiveness of adopting labor protection. [ABSTRACT FROM AUTHOR]

Preoperative iris vessel area density and time interval of sequential cataract surgery can effectively predict perceived pain during second-eye phacoemulsification surgery in patients with bilateral cataracts Purpose: To explore clinical indicators to predict perceived pain during second-eye phacoemulsification surgery in patients with bilateral cataracts. Setting: Shanghai General Hospital, China. Design: A case‒control study and a prospective cohort study. Methods: Patients with age-related cataract who underwent first-eye or second-eye uneventful phacoemulsification surgery were enrolled. Before surgery, ocular examination results, including vessel area density (VAD) and vessel skeleton density (VSD), obtained by optical coherence tomography angiography examination of the iris were performed. Patients completed a visual analog scale pain survey 3 times postoperatively: 1 hour, 3 hours, and 24 hours postoperatively. Results: 70 patients were enrolled in the case‒control study, and the pain scores of the second-eye surgery group under local anesthesia were significantly greater than those of the first-eye surgery group (P =.0005). Preoperative iris VAD in the second-eye group affected perioperative pain scores (P =.0047). The optimal cutoff value of VAD was 0.2167 with a specificity of 76% and a sensitivity of 62%. In the prospective cohort study, 124 patients were included in the second-eye group. Preoperative iris VAD (P =.0361) and the time interval (P =.0221) were independent factors for second-eye surgery pain. Combined with preoperative iris VAD and surgical interval, the negative predictive value and positive predictive value were 0.95 and 0.29 for predicting moderate pain or above, the sensitivity and specificity were 0.97 and 0.23, respectively. Conclusions: The combination of iris VAD and the time interval between both eye surgeries can be an effective method to predict the timing of the second-eye cataract surgery and to avoid intraoperative pain. [ABSTRACT FROM AUTHOR]