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Use of electronic cigarettes (e‐cigarettes) has increased significantly over the past decade due to consumer perception that these products represent a less risky alternative to combustible cigarettes. E‐liquids generally contain a simple mix of vegetable glycerin, propylene glycerol, nicotine, organic acids, and flavourings. Regulators require that harmful and potentially harmful constituents (HPHCs) that might cause harm to the consumer must be monitored in the aerosol generated by e‐cigarettes and in cigarette smoke (CS). To quantify HPHCs in aerosols from commercial flavoured e‐cigarettes in Chinese market, this study has systematically compared levels of HPHCs, including eight carbonyls, five volatile organic compounds, four tobacco‐specific nitrosamines, 16 polycyclic aromatic hydrocarbons, and seven heavy metals, in the aerosols of four market‐leading flavoured e‐cigarettes and mainstream CS, alongside in vitro cytotoxicity and mutagenicity assays. The vast majority of HPHCs were either undetected or significantly lower in the e‐cigarette aerosols than in commercial CS or reference CS (3R4F). Where HPHCs were detected, there were small variations among the different flavoured e‐cigarettes. In the neutral red uptake and Ames assays, aqueous extracts of the e‐cigarette aerosols did not induce obvious cytotoxicity or mutagenicity, whereas CS aqueous extract showed dose‐related cytotoxicity and mutagenicity. Collectively, these results indicate that use of e‐cigarettes might potentially lead to a significant reduction in exposure to harmful substances, with fewer cytotoxic and mutagenic effects, as compared with conventional smoking. Further studies based on human puffing conditions and longer evaluation periods will be needed to substantiate this potential. [ABSTRACT FROM AUTHOR]

2‐isopropyl‐N,2,3‐trimethylbutyramide (WS‐23) is a well‐known artificial synthesis cooling agent widely used in foods, medicines, and tobaccos. As a commonly cooling agent in e‐cigarette liquids, WS‐23 has led to concerns about the inhalation toxicity with the prosperous of e‐cigarettes in recent years. Thus, the aim of this study is to assess the acute and subacute inhalation toxicity of WS‐23 in Sprague–Dawley (SD) rats according to the Organization for Economic Cooperation and Development (OECD) guidelines. In the acute toxicity study, there was no mortality and behavioral signs of toxicity at the limit test dose level (340.0 mg/m3) in the exposure period and the following 14‐day observation period. In the subacute inhalation toxicity study, there was no significant difference observed in the body weights, feed consumption, and relative organ weights. Haematological, serum biochemical, urine, and bronchoalveolar lavage fluid (BALF) analysis revealed the non‐adverse effects after 28‐day repeated WS‐23 inhalation (342.85 mg/m3), accompanied by slight changes in few parameters which returned to normal during the 28‐day recovery period. The histopathologic examination also did not show any differences in vital organs. In conclusion, the maximum tolerated dose for WS‐23 acute inhalation is not less than 340.0 mg/m3, and the No Observed Adverse Effect Level (NOAEL) of WS‐23 subacute inhalation was determined to be over 342.85 mg/m3. The acute and subacute inhalation toxicity of WS‐23 in Sprague‐Dawley (SD) rats have been evaluated in this study. The results suggested that the maximum tolerated dose for WS‐23 acute inhalation is not less than 340 mg/m3, and the No Observed Adverse Effect Concentration (NOAEC) for WS‐23 subacute inhalation is over 342.85 mg/m3. [ABSTRACT FROM AUTHOR]

A novel organic–inorganic nanocomposite material of rare earth ions/ poly(styrene‐alt‐maleic anhydride) ionic salt/ reduced graphene oxide (Re3+/SMA‐Is/rGO) was prepared successfully. Poly(styrene‐alt‐maleic anhydride) ionic salt functionalized reduced graphene oxide (SMA‐Is/rGO) was processed with two methods of π–π conjugation and ionization; rare earth ions (Re3+ = La3+, Ce3+ Pr3+) was doped on the surface of rGO by physical mixing. SMA‐Is reduced surface energy and enlarged the interlayer spacing between rGO nanosheets, ensuring that Re3+/SMA‐Is/rGO could form a uniform dispersed phase in the organic coating. The anti‐corrosion performance of the nanocomposite coating was measured by electrochemical techniques in corrosive medium, revealing that introducing the nanocomposite to epoxy matrix exhibited a significant decline of the increase of corrosion potential and corrosion current density. In all samples, La3+/SMA‐Is/rGO had the highest anti‐corrosion performance, and the protection efficiency on mild steel was up to 98.97%. [ABSTRACT FROM AUTHOR]

Recently, 2D organic–inorganic hybrid lead halide perovskites have attracted intensive attention in solid‐state luminescence fields such as single‐component white‐light emitters, and rational optimization of the photoluminescence (PL) performance through accurate structural‐design strategies is still significant. Herein, by carefully choosing homologous aliphatic amines as templates, isotypical perovskites [DMEDA]PbCl4 (1, DMEDA=N,N‐dimethylethylenediamine) and [DMPDA]PbCl4 (2, DMPDA=N,N‐dimethyl‐1,3‐diaminopropane) having tunable and stable broadband bluish white emission properties were rationally designed. The subtle regulation of organic cations leads to a higher degree of distortion of the 2D [PbCl4]2− layers and enhanced photoluminescence quantum efficiencies (<1 % for 1 and 4.9 % for 2). The broadband light emissions could be ascribed to self‐trapped excitons on the basis of structural characterization, time‐resolved PL, temperature‐dependent PL emission, and theoretical calculations. This work gives a new guidance to rationally optimize the PL properties of low‐dimensional halide perovskites and affords a platform to probe the structure–property relationship. [ABSTRACT FROM AUTHOR]

Objective With an increased use of endoscopic retrograde cholangiopancreatography ( ERCP), post-ERCP complications have attracted much attention. We aimed to identify independent risk factors of post- ERCP pancreatitis ( PEP) and hyperamylasemia, and to develop a simple scoring system of the factors contributing to the clinical prevention against PEP. Methods A retrospective single-center analysis was performed in 4234 ERCP procedures between September 2007 and December 2012. Patient-related and procedure-related risk factors for PEP and post-ERCP hyperamylasemia were identified by univariate and multivariate regression analyses. A scoring system was developed based on the independent risk factors. Results PEP occurred in 226 (5.3%) ERCP procedures and hyperamylasemia in 774 (18.3%) procedures. Female gender (odds ratio [ OR] 1.449), first-time ERCP ( OR 1.745), latent jaundice ( OR 1.917), difficult cannulation ( OR 3.317) and pancreatography ( OR 1.823) were all proven to be significant risk factors for predicting PEP. In addition, difficult cannulation ( OR 1.990) and pancreatography ( OR 2.009), age <60 years ( OR 1.294), prior diabetes ( OR 0.614), biliary duct stent placement ( OR 1.884) and nasobiliary drainage ( OR 1.613) were associated with developing hyperamylasemia. Prophylactic pancreatic duct stent ( PS) might prevent against PEP in significantly high-risk patients (score ≥6). Conclusions Both patient-related and procedure-related risk factors are important for predicting PEP and post-ERCP hyperamylasemia. Technical procedures, for example, PS, are necessary to prevent PEP in patients at the highest risk. [ABSTRACT FROM AUTHOR]