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Obtaining accurate lattice thermal conductivity data of LiF under extreme conditions not only provides important reference for performance evaluation, prediction, and control of materials, but also helps to alleviate the significant challenges of precise experimental measurements. The high-temperature phonon properties and lattice thermal conductivity (LTC) of solid LiF were calculated by combining on-the-fly machine learning force fields (MLFFs) with the Green–Kubo method. The introduction of MLFF successfully combines the accuracy of ab initio molecular dynamics with the scalability advantage of classical molecular dynamics. At high temperatures, there is a significant enhancement in the vibrational coupling between the acoustic and optical branches of LiF, as well as resonant effects between Li and F atoms, resulting in strong anharmonicity. Additionally, the main peak of the phonon density of states shows a noticeable redshift compared to the harmonic case. The enhanced coupling of TO and TA modes at high temperature leads to a significant increase in phonon scattering rate. By considering higher-order phonon anharmonicity, the predicted LTC is significantly reduced compared to the results obtained from considering only three-phonon interactions. Along the Hugoniot curve up to 100 GPa (2150 K), the predicted LTC agrees well with the experimental values. These findings demonstrate the crucial role of phonon anharmonicity in promoting phonon scattering. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the mental health of paediatric cochlear implant users and analyse the relationship between six dimensions (movements, cognitive ability, emotion and will, sociality, living habits and language) and hearing and speech rehabilitation. Methods: Eighty-two cochlear implant users were assessed using the Mental Health Survey Questionnaire. Age at implantation, time of implant use and listening modes were investigated. Categories of Auditory Performance and the Speech Intelligibility Rating Scale were used to score hearing and speech abilities. Results: More recipients scored lower in cognitive ability and language. Age at implantation was statistically significant (p < 0.05) for movements, cognitive ability, emotion and will, and language. The time of implant usage and listening mode indicated statistical significance (p < 0.05) in cognitive ability, sociality and language. Conclusion: Timely attention should be paid to the mental health of paediatric cochlear implant users, and corresponding psychological interventions should be implemented to make personalised rehabilitation plans. [ABSTRACT FROM AUTHOR]

In order to solve the problems of high energy consumption of condensation polymerization and small variety of monomers for ring-opening polymerization of cyclic esters in the process of synthesizing polyesters, six polyester products were successfully synthesized using aminophenolic iron-based complexes to catalyze the copolymerization reaction of cyclic anhydride and epoxides. Nuclear magnetic resonance hydrogen spectroscopy (¹H NMR), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), contact angle meter, thermogravimetric analysis (TG), differential scanning calorimetry (DSC), and gel permeation chromatography (GPC) were used to characterize the structures and properties of polyester. The results showed that all the polyesters with hydrophilic properties were amorphous structures. The initial decomposition temperature (T5%) of polyesters was 250~300 °C and the glass transition temperature (Tg) of polyesters was 55~139 °C. Polyesters containing rigid cyclohexane structure showed higher Tg and better thermomechanical stability performance. [ABSTRACT FROM AUTHOR]

Objective: To assess the prevalence of metabolic syndrome (MetS) in Chinese adults living in Ningbo and to examine the association between alcohol consumption and MetS and its medical components.Design: A representative survey in Ningbo was conducted in 2015 covering socio-demography. A FFQ together with additional questionnaires was used to collect information on alcohol consumption, diet, demography, lifestyle and medical information. Multivariable logistic regression and generalised linear models were used to examine the association between alcohol consumption and both MetS and its medical components, respectively.Setting: Ningbo, China.Participants: A total of 2853 adults ≥ 20 years (44 % men) in this final analysis.Results: The prevalence of frequent alcohol drinkers and MetS was 29·9 % and 28·0 %, respectively. Significantly higher prevalence of MetS and mean values of medical components were found in the group of frequent alcohol drinkers with an exception for HDL-cholesterol, compared with less or non-alcohol drinkers. Frequent alcohol consumption was associated with higher odds of developing MetS and positively associated with medical components excepting waist circumference.Conclusions: Frequent alcohol consumption contributed to a higher prevalence of MetS and unfavourable influence on MetS and its medical components among Chinese adults. A public health intervention on alcohol restriction is necessary for the prevention and control of the ongoing epidemic MetS. [ABSTRACT FROM AUTHOR]