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Objectives: Laryngeal complications have been reported after endotracheal intubation and prone positioning in patients with critical coronavirus disease 2019 (COVID‐19), but their association is unclear. In this study, we investigated the rate of laryngeal complications in patients with COVID‐19 compared to an alternative condition (control group). Methods: We retrospectively analyzed the data of 40 patients who underwent endotracheal intubation for either COVID‐19 or an alternative condition (control group). Data on age, sex, body mass index (BMI), cardiovascular disease (CVD) risk factors, use of prone therapy, duration of endotracheal intubation, and duration from extubation/tracheostomy to laryngeal evaluation were collected from medical records. Results: There were no significant differences in BMI, frequency of CVD risk factors, duration of endotracheal intubation, or duration from extubation/tracheostomy to laryngeal evaluation between the two groups. In the COVID‐19 group, all patients adopted the prone position. In comparison, only one patient in the control group adopted the prone position. Significant differences were observed between the two groups regarding the incidence of vocal fold immobility and laryngeal granuloma. Conclusion: Laryngeal complications were more common in the COVID‐19 group than in the control group. Prone positioning may be a risk factor for these complications. Level of Evidence: 4. [ABSTRACT FROM AUTHOR]

ABSTRACT Thermoelectric (TE) properties of flexible and free-standing poly(3,4-ethylenedioxythiophene) (PEDOT) films synthesized via galvanostatic polymerization of 3,4-ethylenedioxythiophene in propylene carbonate containing sulfated poly(β-hydroxyethers) (S-PHE) as polymer electrolyte were elaborately studied. Both electrical conductivities ( σ) and Seebeck coefficients ( S) of the PEDOT:S-PHE films were increased by decreasing the temperature ( T) or by increasing the current density ( J) during electrosynthesis. Possible reasons for the lack of a trade-off relation commonly observed between σ and S are discussed on the basis of SEM and oxidation-level measurements. Preparation of the PEDOT:S-PHE films was optimized with respect to T and J. In addition, the oxidation level of the PEDOT:S-PHE films was controlled by potential and the change of their TE performances was discussed in conjunction with the change of chemical species involved. The power factor ( PF = σS2) of the PEDOT:S-PHE films reached 7.9 μW m−1 K−2, leading to a dimensionless TE figure-of-merit ( ZT) of 0.013. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017, 55, 524-531 [ABSTRACT FROM AUTHOR]

Specific solvatochromic D-π-A-type pyridinium dyes were designed and developed as photosensitizers for dye-sensitized solar cells (DSSCs). The dyes have N-sulfobutylpyridinium or N-(carboxybutyl)pyridinium bromide as an electron-withdrawing anchoring group. The two dyes show specific solvatochromism, leading to a large bathochromic shift of the absorption band in halogenated solvents. Moreover, a dye-adsorbed TiO2 film immersed into halogenated solvents exhibits specific solvatochromism, as does a dye solution of halogenated solvents. DSSCs based on specific solvatochromic D-π-A-type pyridinium dyes and halogenated solvents as electrolyte solvent were prepared and their photovoltaic performance investigated. It was found that the appropriate combination of solvatochromic dyes with electrolyte solution and the effective interaction between solvatochromic dyes and TiO2 surface can lead to not only an enhancement of light-harvesting efficiency (LHE), but also efficient electron injection from the dye to the conduction band (CB) of TiO2. This work demonstrates that the solvatochromism of organic dyes is a key consideration for high-performance DSSCs based on organic dye sensitizers. [ABSTRACT FROM AUTHOR]

Carbazole-type donor-π-acceptor (D-π-A) fluorescent dyes ( SO1 and SO2), each containing a diphenylamino system as an electron-donating group and a nitro moiety as an electron-accepting group, have been designed and synthesized, and their photophysical properties in solution and in the solid state have been investigated. The absorption and fluorescence properties of SO1 and SO2 in solution are similar, and both dyes exhibited moderate fluorescence quantum yields. In the solid state, however, the dye SO2, with a butyl substituent on the carbazole ring, exhibited red fluorescence at around 620 nm, whereas the dye SO1, with no substituent on the carbazole ring, did not exhibit these solid-state fluorescence properties. Furthermore, the dye SO2 exhibited weak mechanofluorochromic (MFC) properties: grinding of as-recrystallized dyes induces slight bathochromic shifts of the fluorescence excitation and emission maxima. To elucidate the effects of molecular and crystal structures on the solid-state fluorescence properties, we performed semiempirical molecular orbital calculations (PM3 and INDO/S) and single-crystal X-ray structural analysis. The X-ray crystal structures of SO1 and SO2 demonstrated that a continuous intermolecular π-stacking between the fluorophores was observable in the crystal structure of SO1, but not in that of SO2. The MO calculations revealed that SO1 and SO2 have similarly large dipole moments in the ground state ( μg ≈ 8 D). The relationship between the observed solid-state photophysical properties and the molecular and crystal structures of the carbazole-type D-π-A fluorescent dyes are discussed on the basis of experimental results and MO calculations. It is found that the formation of a continuous intermolecular π-stacking between the fluorophores causes a drastic fluorescence quenching in the solid state and that D-π-A fluorescent dyes with very large dipole moments can reduce the MFC properties, due to strong dipole-dipole interactions between the fluorophores in the solid state. [ABSTRACT FROM AUTHOR]

Our recent results on the synthesis and properties of a novel family of polysilsesquioxanes having oligothiophenes were reviewed. The polymers anchored on SiO2 or ITO substrates showed excellent mechanical hardness due to the formation of a threedimensional siloxane network structure and chemical linkage between polymer and the surface of metal-oxide substrates. Optical, electrochemical, and electrical properties of polymers were also investigated. [ABSTRACT FROM AUTHOR]