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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]

Background: This study aimed at investigating the relationship between the weekend catch-up outdoor duration (WCOD) and prevalence of myopia among students in China. Methods: This cross-sectional study recruited participants in 107 schools (six cities, 30 districts) from China from May to June 2021. Demographic characteristics (age, grade, sex, ethnicity, BMI, resident, and parents' myopia), optically habits (bad writing habits, working/studying time per day, continuous working/studying time per day, and screen time per day) and outdoor duration (weekday and weekend) were obtained from questionnaire. WCOD was defined as outdoor time 1 h longer on weekends than on weekdays. Spherical equivalent (SE) of refractive error were measured with non-cycloplegic refraction. Adjusted multivariate logistic regression analysis was performed to evaluate the relationship between WCOD and prevalence of myopia. Results: Students with myopia had shorter WCOD compared with those without myopia (P < 0.001). Adjusted multivariate logistic regression analyses showed negative associations between WCOD and prevalence of myopia in Chinese students, especially in students with WCOD of 2–3 h (OR = 0.577, P < 0.001) and 3–4 h (OR = 0.571, P = 0.004) when the weekday outdoor duration was 0.5–1 h, as well as students with WCOD of 2–3 h (OR = 0.614, P = 0.003) when the weekday outdoor duration was 1–2 h. Similar results were observed in students with high myopia. Students with high myopia had shorter WCOD compared with those without high myopia (P = 0.001). Negative associations between WCOD and prevalence of high myopia were significant in students with WCOD of 1–2 h when the weekday outdoor duration was < 0.5 h (OR = 0.585, P = 0.007) and 0.5–1 h (OR = 0.537, P = 0.018). Conclusion: Our study, for the first time, reported that a WCOD have a potential to reduce the prevalence of myopia and high myopia in Chinese students. [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]

Existing evidence about associations between change in body mass index (BMI) and waist-to-height ratio (WHtR) change and high blood pressure are relatively limited. We aimed to investigate the associations of general overweight (based on BMI) and abdominal obesity (based on WHtR) change with high blood pressure in Chinese children. A school-based cohort study in Ningbo region (China) was conducted among children with baseline evaluations in October 2016 with follow-up two years later. A total of 1432 children aged 11–13 years participated in this study. Our results showed that a change from normal BMI or WHtR to overweight or abdominal obesity in children was associated with high blood pressure (adjusted odds ratio (AOR), 2.62; p<0.05 or AOR, 2.79; p<0.05, respectively). In addition, an increased risk of high blood pressure was observed in children who maintained overweight or abdominal obesity (AOR, 1.67; p<0.05 or AOR, 1.69; p<0.05, respectively), but not in children who experienced remission to non-excess weight. Interestingly, children who increased BMI or WHtR had greater impact on SBP than on DBP. The 2-year longitudinal study indicated that general overweight or abdominal obesity can predict the risk factor of high blood pressure in children. However, children who remitted to non-excess weight did not exhibit an increased risk of high blood pressure. [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]

Objective: To examine the association between 25-Hydroxyvitamin D (25(OH)D) levels and sleep duration among Chinese adolescents. Subjects and methods: A school-based cross-sectional study was conducted among Chinese adolescents in 2017. Data on a total of 800 adolescents aged 8–14 years was used for this study. Anthropometric measurements such as height and weight were measured by trained research staff. Serum 25(OH)D and lipids were measured in the laboratory. Sleep habits and other health-related behaviors were tested by questionnaire. Results: 25(OH)D levels were significantly positively correlated with sleep duration (r = 0.11, p < 0.05). In multivariate logistic regression analyses, insufficiency/deficiency of vitamin D (25(OH)D ≤ 20 ng/mL) was significantly associated with increased probability of short sleep (AOR = 1.67, 95% CI = 1.14–2.43). Conclusions: Low 25(OH)D levels were independently associated with the risk of insufficient sleep in Chinese adolescents. [ABSTRACT FROM AUTHOR]