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Background Limited data are available on the relationship between seasonal factors and obstructive sleep apnea-hypopnea syndrome (OSAHS) in China. The aim of this study was to investigate the effects of seasonal factors on the severity of OSAHS in children. Methods Children presenting with snoring and/or mouth breathing, suspected of having OSAHS, and admitted to the Department of Respiratory Medicine of the Children's Hospital of Soochow University from December 2016 to February 2022 were enrolled in this study. The severity of OSAHS was determined by full-night polysomnography (PSG) in the sleep laboratory. The correlation between seasonal factors and PSG monitoring results was analyzed. Results Of the 589 included patients, 301 cases (51.1%) were diagnosed with OSAHS. Among them, 77 cases (25.6%) were detected in spring, 74 cases (24.6%) were detected in summer, 59 cases (19.6%) were detected in autumn, and 91 cases (30.2%) were detected in winter. There were 238 cases (79.1%) of tonsillitis hypertrophy, 276 cases (91.7%) of adenoid hypertrophy, 215 cases (71.4%) of rhinitis/sinusitis, and 36 cases (12.0%) of asthma. The proportion of rhinitis/sinusitis and tonsillar hypertrophy in spring was higher than that in summer (P = 0.015 and 0.036, respectively), and the proportion of adenoid hypertrophy in winter was higher than that in summer (P = 0.024). The diagnostic rate of severe OSAHS in winter was higher than that in summer (χ2 = 7.053, P = 0.008). The respiratory arousal index in winter was higher than that in summer (H = -39.297, P = 0.018), and the spontaneous arousal index in spring was higher than that in autumn (H = 44.059, P = 0.020). It was found that the rapid eye movement (REM)-apnea index (AI) in spring and winter was higher than that in summer (H = 52.292, -52.554; all P H = -35.570, P = 0.008). The REM-AI in winter and spring was higher than that in summer and autumn, respectively (H = -33.929 and − 38.632; H = 30.665 and 35.368, all P

Replacing fossil-based polymers with renewable bio-based polymers is one of the most promising ways to solve the environmental issues and climate change we human beings are facing. The production of new lignocellulose-based polymers involves five steps, including (1) fractionation of lignocellulose into cellulose, hemicellulose, and lignin; (2) depolymerization of the fractionated cellulose, hemicellulose, and lignin into carbohydrates and aromatic compounds; (3) catalytic or thermal conversion of the depolymerized carbohydrates and aromatic compounds to platform chemicals; (4) further conversion of the platform chemicals to the desired bio-based monomers; (5) polymerization of the above monomers to bio-based polymers by suitable polymerization methods. This review article will focus on the progress of bio-based monomers derived from lignocellulose, in particular the preparation of bio-based monomers from 5-hydroxymethylfurfural (5-HMF) and vanillin, and their polymerization methods. The latest research progress and application scenarios of related bio-based polymeric materials will be also discussed, as well as future trends in bio-based polymers.

Ferroelectric poly(vinylidene fluoride)/semiconductive polythiophene (P3CPenT) blend monolayers were developed at varying blend ratios using the Langmuir-Blodgett technique. The multilayered blend nanosheets show much improved surface roughness that is more applicable for electronics applications than spin-cast films. Because of the precisely controllable bottom-up construction, semiconductive P3CPenT were well dispersed into the ferroelectric PVDF matrix. Moreover, the ferroelectric matrix contains almost 100% β crystals: a polar crystal phase responsible for the ferroelectricity of PVDF. Both the good dispersion of semiconductive P3CPenT and the outstanding ferroelectricity of the PVDF matrix in the blend nanosheets guaranteed the success of ferroelectric organic non-volatile memories based on ferroelectricity-manipulated resistive switching with a fresh high ON/OFF ratio and long endurance to 30 days.

A Cellulose nanofiber (CNF) is an amazing nanomaterial produced from ubiquitous sources with outstanding mechanical, chemical, and barrier properties. This report describes facile functionalization of CNF with trichloro(1H,1H,2H,2H-heptadecafluorodecyl)silane (THFS). The paste form CNF was solvent exchanged from initial water to AK-225 (a mixture of 3,3-dichloro-1,1,1,2,2-pentafluoropropane and 1,3-dichloro-1,1,2,2,3-pentafluoropuropane) before surface modification with THFS. The modified CNFs were dispersed uniformly in AK-225. The CNF film, which was prepared using simple drop casting, showed a superhydrophobic surface with a water contact angle of 160° and oleophilicity with a hexane contact angle of less than 35°. The modified CNF assembly is thermally stable, optically transparent and resistant to corrosive environment (acidic, basic and seawater solutions). The separation of oil and water mixtures was demonstrated using steel mesh coated with modified CNF. Separation efficiency greater than 99% was achieved by simple gravitational force for hydrocarbons and organic solvents. The as-prepared mesh can be used repeatedly more than 50 times with the same efficiency as the initial state.

We fabricated poly(vinylidene fluoride-co-trifluoroethylene), P(VDF-TrFE) 75/25 mol% Langmuir–Blodgett (LB) nanofilms by the assistance of amphiphilic poly(N-dodecylacrylamide) (pDDA) nanosheets. The nanosheet is formed based on a well-organized hydrogen bonding network among pDDA amide groups at the air–water interface. By the introduction of the pDDA nanosheet, the film stability of the P(VDF-TrFE) Langmuir film was greatly improved with a twofold increase in the collapse surface pressure to 57 mN m−1 of pure P(VDF-TrFE). Then, the P(VDF-TrFE) Langmuir film was endowed a good transfer ability with a unity transfer ratio irrespective of its non-amphiphilicity. Absorbance of the amide group of pDDA in UV-vis spectra shows a good linear relation with the film thickness. The result indicates that the multilayered film takes a uniform layered structure. The β-crystal content in as-prepared LB nanofilms with no post-treatment is up to 80%, one of the highest values ever reported. The monolayer thickness was determined as 3.5 nm by AFM measurements. The good film properties make the as-prepared P(VDF-TrFE)/pDDA LB ultrathin films (18 nm) available for ferroelectricity measurement using macroscopic methods such as the typical Sawyer–Tower circuit, which is usually challenging for other ultrathin films. The measurements demonstrate improved ferroelectricity, with a high remanent polarization value of 5.0 μC cm−2 at 10 Hz.

Fluorinated polymer nanoparticle films were prepared by dissolving amphiphilic fluorinated polymer, poly (N-1H, 1H-pentadecafluorooctylmethacrylamide) (pC7F15MAA) in two miscible solvents (AK-225 and acetic acid). A superhydrophobic and porous film was obtained by dropcasting the solution on substrates. With higher ratios of AK-225 to acetic acid, pC7F15MAA was densified around acetic acid droplets, leading to the formation of pC7F15MAA nanoparticles. The condition of the nanoparticle film preparation was investigated by varying the mixing ratio or total concentration. A highly sensitive dissolved oxygen sensor system was successfully prepared utilizing a smart surface of superhydrophobic and porous pC7F15MAA nanoparticle film. The sensitivity showed I0/I40 = 126 in the range of dissolved oxygen concentration of 0 ~ 40 mg L-1. The oxygen sensitivity was compared with that of previous reports.