The influence of the Beijing Winter Olympic games on the demand for winter sports: An empirical analysis based on the Baidu Index.

Background: The 2022 Beijing Winter Olympics is a representative large-scale sporting event, which not only promotes the development of the national and regional economy, society, and culture but also increases the demand of residents for winter sports, thus helping achieve the grand goal of "encouraging 300 million people to participate in winter sports." This research explores the influence of the Beijing Winter Olympics on residents' demand for winter sports in the Beijing-Tianjin-Hebei and Yangtze River Delta urban agglomerations in China. Methods: Applying big data mining techniques, the Baidu Index of Winter Olympics-related terms are used to measure residents' interest in the Beijing Winter Olympics, and the ratio of the Baidu Index of five winter sports (ice skating, ice hockey, curling, luge, and skiing) to the number of internet searches is used to capture residents' demand for winter sports. Moreover, we explore the spatial-temporal pattern of the interest in the Winter Olympics and the demand for winter sports and construct an econometric model to test the driving effect of the Winter Olympics empirically. Results: The results show that 1) since 2011, interest in Winter Olympics has been on the rise, and the interest of residents in Beijing-Tianjin-Hebei has been higher than that of the Yangtze River Delta; 2) the demand for skating and skiing, which are two popular winter sports, shows a declining geographical concentration, indicating that the popularity of these two sports is on the increase; 3) the demand for winter sports in the peripheral cities in Beijing-Tianjin-Hebei shows a trend of specialization, while Beijing, Tianjin, and some cities in the Yangtze River Delta present a trend of diversification; and 4) the interest in the Beijing Winter Olympics influences the demand for winter sports positively. Conclusion: This study shows that the increase in interest in the Beijing Winter Olympics boosts residents' demand for winter sports, which implies that hosting Winter Olympics successfully drives winter sports participation in China.

Catalytic site flexibility facilitates the substrate and catalytic promiscuity of Vibrio dual lipase/transferase.

Although enzyme catalysis is typified by high specificity, enzymes can catalyze various substrates (substrate promiscuity) and/or different reaction types (catalytic promiscuity) using a single active site. This interesting phenomenon is widely distributed in enzyme catalysis, with both fundamental and applied importance. To date, the mechanistic understanding of enzyme promiscuity is very limited. Herein, we report the structural mechanism underlying the substrate and catalytic promiscuity of Vibrio dual lipase/transferase (VDLT). Crystal structures of the VDLT from Vibrio alginolyticus (ValDLT) and its fatty acid complexes were solved, revealing prominent structural flexibility. In particular, the "Ser-His-Asp" catalytic triad machinery of ValDLT contains an intrinsically flexible oxyanion hole. Analysis of ligand-bound structures and mutagenesis showed that the flexible oxyanion hole and other binding residues can undergo distinct conformational changes to facilitate substrate and catalytic promiscuity. Our study reveals a previously unknown flexible form of the famous catalytic triad machinery and proposes a "catalytic site tuning" mechanism to expand the mechanistic paradigm of enzyme promiscuity.

Subacute dermal toxicity study of bensulfuron-methyl in Sprague-Dawley rats.

Background: Bensulfuron-methyl has recently attracted attention given its widespread use as an herbicide in crops, especially its transdermal safety. However, no dermal toxicity study of this pesticide to mammals has been reported. The present study aims to investigate subacute dermal toxicity of bensulfuron-methyl following repeated doses exposure.Methods: Forty-eight Sprague-Dawley rats were randomly divided into four groups: a normal control group and bensulfuron-methyl groups of different concentrations (250, 500, 1000 mg/kg.bw/day). The rats were topically applied with the substance dermally for 6 h per day for 28 days. At the end of the experiment, all rats were monitored for any changes in their hematological, biochemical parameters, and pathological and histological sections.Results: There were no statistically significant differences (P ≥ 0.05) in the hematological parameters and biochemical parameters. The pathological histological results of rats in the control and the highest concentration group showed no significant abnormalities. The NOAEL of subacute dermal toxicity study was found to be 1000 mg/kg.bw/day in both female and male rats.Conclusion: The result indicated that bensulfuron-methyl is probably safe for humans as a pesticide.

Estimated individual inhaled dose of fine particles and indicators of lung function: A pilot study among Chinese young adults.

Fine particle (PM2.5)-related lung damage has been reported in most studies regarding environmental or personal PM2.5 concentrations. To assess effects of personal PM2.5 exposures on lung function, we recruited 20 postgraduate students and estimated the individual doses of inhaled PM2.5 based on their microenvironmetal PM2.5 concentrations, time-activity patterns and refereed inhalation rates. During the period of seven consecutive days in each of the four seasons, we repeatedly measured the daily lung function parameters and airway inflammation makers such as fractional exhaled nitric oxide (FeNO) as well as systemic inflammation markers including interleukin-1ß on the final day. The high individual dose (median (IQR)) of inhaled PM2.5 was 957 (948) µg/day. We observed a maximum FeNO increase (9.1% (95%CI: 2.2-15.5)) at lag 0 day, a maximum decrease of maximum voluntary ventilation (11.8% (95% CI: 4.6-19.0)) at lag 5 day and a maximum interleukin-1ß increase (103% (95% CI: 47-159)) at lag 2 day for an interquartile range increase in the individual dose of inhaled PM2.5 during the four seasons. Short-term exposure to PM2.5 assessed by the individual dose of inhaled PM2.5 was associated with higher airway and systemic inflammation and reduced lung function. Further studies are needed to understand better underlying mechanisms of lung damage following acute exposure to PM2.5.