After the epidemic, the tourism industry is experiencing an unprecedented revival, and the problem of information security has gradually become an important factor restricting the development of tourism. Through in-depth analysis of the background of tourism revival, the challenges faced and domestic and foreign laws and regulations and other issues, this paper puts forward a series of targeted solutions, including investment in technical construction, provide infrastructure and other technical means, as well as improve the relevant laws and regulations, establish and improve the enterprise management mechanism and strengthen supervision and other non-technical strategies. These measures help to ensure the data security of the tourism industry in the process of digital transformation, and promote the healthy and sustainable development of the tourism industry.
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Switchable ortho/ipso-cyclization of N-arylpropynamides induced with N-sulfanylsuccinimides as general sulfur reagents is reported. In the presence of MeOH, para-fluoro N-arylpropynamides exclusively undergo the ipso-cyclization to give 3-sulfenyl azaspiro[4,5]trienones. Two kinds of bioactive heterocycles, benzothieno-[3,2-b]quinoline and -[2,3-c]quinolone, have been directly and efficiently prepared from the corresponding sulfenylated products.
Abstract [3+2] Cycloaddition of a series of substituted N ‐tosylaziridines with various nitriles promoted by Bi(OTf) 3 is described for the synthesis of substituted imidazolines under mild reaction conditions. The procedure works well over a range of substrates to give the corresponding products in good to excellent yields (up to 99 %).
With sulfites or sulfonyl hydrazides as the sulfonyl source, sulfonylation mediated by iodine-containing reagents has achieved much progress in recent years.According to different positions of sulfonylation, the progress involved the introduction of sulfonyl group mediated by various iodine-containing reagents is summarized.
The KOH-, K2CO3-, or Et3N-catalyzed ring-opening reaction of N-tosylaziridines using the nitrogen atom of a series of (E)-aldoximes and (E)-ketoximes as a nucleophilic atom instead of an oxygen atom was developed to construct various nitrones under mild reaction conditions. Diverse (E)-aldoximes and (E)-ketoximes were demonstrated to be compatible with this reaction and the products of O-ring-opening reactions were not detected for most examples.
A simple and efficient metal-free sulfenylation/cyclization of aryl alkynoates has been developed, obtaining various 3-sulfenylated coumarins in moderate to excellent yields. In the presence of BF3·Et2O, the stable and readily accessible N-sulfanylsuccinimides were employed as electrophiles to induce the 6-endo-dig electrophilic cyclization of alkynoates. The reaction using substrates bearing a methoxy group on the phenoxy ring proceeded in an exclusively distinct pathway via either ipso sulfenylcyclization or sulfenylation of the phenoxy ring depending on the different locations of the methoxy substituent. The resulting 3-sulfenylated coumarins can be readily transformed to 3-sulfinylated or 3-sulfonylated coumarins under different oxidation conditions.
Abstract Objective To evaluate and explore the efficacy of CO 2 fractional laser in treating post‐burn hypertrophic scars in children through Meta‐analysis. Methods English databases (PubMed, Web of Science and The National Library of Medicine), as well as Chinese databases (China National Knowledge Infrastructure and Wanfang Data) were searched. RevMan 5.3 software was used to data analysis. Results A total of 10 pieces of literature were included, involving 413 children. Meta‐analysis showed that: (1) The average Vancouver Scar Scale after surgery was significantly lower than that before surgery [weight mean difference (WMD) = −3.56, 95% confidence interval (CI):−4.53,−2.58, p < 0.001]; (2) After CO 2 fractional laser, pigmentation [WMD = −0.74, 95% CI:−1.10,−0.38, p < 0.001], pliability [WMD = −0.92, 95% CI:−1.20,−0.65, p < 0.001], vascularity [WMD = −0.77, 95% CI:−1.09,−0.46, p < 0.001], height [WMD = −0.57, 95% CI:−0.95,−0.19, p < 0.001] were improved compared with those before surgery. (3) The average Visual Analogue Scale (VAS) after surgery was significantly lower than that before surgery [WMD = −3.94, 95% CI:−5.69,−2.22, p < 0.001]. (4) Both Patient and Observer Scar Assessment Scale (POSAS)‐Observer [WMD = −3.98, 95% CI:−8.44,0.47, p < 0.001] and POSAS‐Patient [WMD = −4.98, 95% CI:−8.09,−1.87, p < 0.001] were significantly lower than those before surgery. (5) Erythema and vesicles were the most common complications after CO 2 fractional laser therapy, with an incidence of 4.09%. Conclusion CO 2 fractional laser is beneficial to the recovery of hypertrophic scar after burn in children, and can effectively improve the scar symptoms and signs in children, with desirable clinical efficacy.
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