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BackgroundSchool closures during the COVID-19 pandemic may have exacerbated students’ loneliness, addictive gaming behaviors, and poor mental health. These mental health issues confronting young people are of public concern. ObjectiveThis study aimed to examine the associations between loneliness and gaming addiction behaviors among young people in Hong Kong and to investigate how familial factors, psychological distress, and gender differences moderate these relationships. MethodsThis cross-sectional study was conducted in June 2020 when schools reopened after 6 months of school closures. Participants included 2863 children and adolescents in primary (Grades 4 to 6) and secondary (Grades 7 and 8) schools (female participants: 1502/2863, 52.5%). Chi-square tests, one-way analyses of variance, and independent-samples t tests were performed to compare the differences of distribution in gaming addiction behaviors across gender, age, and other sociodemographic characteristics. Multinomial logistic regression analyses were conducted to identify factors that relate to excessive or pathological gaming behaviors separately, in comparison with leisure gaming. ResultsA total of 83.0% (2377/2863) of the participants played video games during the COVID-19 pandemic. The prevalence of excessive and pathological game addiction behaviors was 20.9% (597/2863) and 5.3% (153/2863), respectively. More male students had gaming addiction symptoms than female students. The multinomial logistic regressions showed that feeling lonely was associated with more problematic gaming behaviors, and the association was stronger for older female students. Low socioeconomic status, less parental support and less supervision, and poor mental health were risk factors for gaming addiction behaviors, especially among primary school students. ConclusionsLoneliness was associated with gaming addiction behaviors; the findings from this study suggested that this association was similar across gender and age groups among young people. Familial support and supervision during school closures can protect young people from developing problematic gaming behaviors. Results of this study have implications for prevention and early intervention on behalf of policy makers and game developers.

The purpose of this study is to examine the efficacy of a three-session free-of-charge counselling model delivered by trained master's-level counsellors. Participants were 105 people whose scores represented mild or moderate levels on the Depression Anxiety Stress Scale and who had not been diagnosed or treated for any psychiatric illness in the past year. Data from the pre-intervention, post-intervention, and three-month follow-up questionnaires were analysed using intent-to-treat analysis. The participants exhibited a reduction in the number of symptoms of depression, anxiety, and stress and an improvement in help-seeking attitudes. These improvements persisted for at least three months. The counselling sessions removed barriers that often deter individuals from seeking professional counselling. The study limitations were its small sample size and the high dropout rates.

Anchoring force loss is critically concerned for the in-service performance of prestressed ground anchors. This time- dependent loss of pretension exerted at the anchor head is caused primarily by stress relaxation, which integrally manifests the rheological properties of the anchor and the geomaterial in which the anchor is embedded. A load-transfer modeling framework was established to derive the time-dependent anchoring force response. The modeling parameters were directly calibrated via element-scale pullout stress relaxation test using a specially developed setup. The applicability and effectiveness of this analytical modeling framework were verified via large-scale laboratory model tests and in situ tests of prestressed anchors. The predictions derived using the presented modeling framework were in good agreement with measurements in both laboratory model tests and in situ tests, particularly for evolutions of anchoring force over time. Sensitivity evaluation of the model parameters was performed to study their respective impact on the anchoring force loss response. This work can provide insights into the understanding of the anchoring force loss behavior of prestressed ground anchors and facilitate their design practice for in-service performance. Key words: prestressed ground anchor, anchoring force loss, relaxation, load transfer La perte de la force d'ancrage est un probleme critique pour la performance en service des ancrages de sol precontraints. Cette perte de la precontrainte exercee a la tete de l'ancrage, qui depend du temps, est causee principalement par la relaxation des contraintes, qui se manifeste integralement par les proprietes rheologiques de l'ancrage et du geomateriau dans lequel il est encastre. Un cadre de modelisation du transfert de charge a ete etabli pour deriver la reponse de la force d'ancrage en fonction du temps. Les parametres de modelisation ont ete directement calibres par un essai de relaxation de la contrainte d'arrachement a l'echelle de l'element a l'aide d'une configuration specialement developpee. L'applicabilite et l'efficacite de ce cadre de modelisation analytique ont ete verifiees par des essais a grande echelle en laboratoire et des essais in situ sur des ancrages precontraints. Les predictions obtenues a l'aide du cadre de modelisation presente etaient en bon accord avec les mesures effectuees lors des essais sur modele en laboratoire et des essais in situ, en particulier pour l'evolution de la force d'ancrage dans le temps. L'evaluation de la sensibilite des parametres du modele a ete realisee pour etudier leur impact respectif sur la reponse de la perte de la force d'ancrage. Ces travaux peuvent permettre de mieux comprendre le comportement de la perte de force d'ancrage des ancrages de sol precontraints et faciliter leur conception pour les performances en service. [Traduit par la Redaction] Mots-cles : ancrage de sol precontraint, perte de force d'ancrage, relaxation, transfert de charge, 1. Introduction Ground anchors have been widely adopted in various anchored geotechnical applications, such as dams, slopes, tunnels, and deep foundation pits, owing to their unique virtues of simple constructability, [...]

The ice crystal icing in aero-engines poses a significant threat to aircraft flight safety, and investigating the correlation between ice crystal size and velocity in icing wind tunnels is essential for correlating ground tests with flight conditions. In this paper, a digital holographic particle tracking velocimetry system is developed and integrated with an icing wind tunnel, and the ice crystal size and velocity are simultaneously measured in experiments at four different wind speeds. The velocity difference between the ice crystal and wind has been experimentally observed, and it increases with both the ice crystal size and wind speed. The normalized velocities of the ice crystals by the wind speeds decrease with size, and the maximum velocity difference in the experiments reaches 28% of the wind speed. Additionally, quantitative correlations between ice crystal size and normalized velocity based on the power function and polynomial model are established. The relationship between the particle Reynolds number of ice crystal and size is also analyzed, resulting in the development of a model based on the power function, and the power index ranges from 1.51 to 1.64. These findings will provide valuable assistance in the calibration and commissioning of the ice crystal simulation system in icing wind tunnels, as well as in exploring the correlation between ground icing tests and flight and in developing corresponding models. [ABSTRACT FROM AUTHOR]

Background: Imagining one's future self is a hallmark of adolescence. But imagining is not enough; adolescents must feel that this future is plausibly likely and take action, which may require pragmatic support from parents. Prior research has examined the effect of parental aspirations and expectations on children's possible self, not the effect of their support. Aims: Therefore, this study assessed the role of parental support on youths' possible selves, strategies, and subjective likelihood of attaining possible selves. Sample: A representative sample of Hong Kong Chinese secondary students aged 12-20 (N = 3,078). Methods: Students responded to an in-class questionnaire. Responses were analysed using generalized linear mixed models and linear mixed models. Results: Content of hoped-for possible selves was mostly about school and career. Content of feared possible selves was more diverse. Girls had more school- and career-focused possible selves and were more likely to have strategies to attain their positive and avoid their negative possible selves. Students reporting more pragmatic support ("If I need to know something about the world, I can ask my parent about it") from parents had more school- and career-focused possible selves and were more likely to believe they could attain their hoped-for and avoid their feared possible selves and to report having at least one strategy to do so. Conclusions: Parental pragmatic support provides students a secure base to engage in their future generally and in their school- and career-focused future in particular.

More and more researchers are studying the heat transfer performance of aeronautical materials at high temperatures. In this paper, we use a quartz lamp to irradiate fused quartz ceramic materials, and the sample surface temperature and heat flux distribution were obtained at a heating power of 45~150 kW. Furthermore, the heat transfer properties of the material were analyzed using a finite element method and the effect of surface heat flow on the internal temperature field was investigated. The results show that the fiber skeleton structure has a significant effect on the thermal insulation performance of fiber-reinforced fused quartz ceramics and the longitudinal heat transfer along the rod fiber skeleton is slower. As time passes, the surface temperature distribution tends to stability and reaches an equilibrium state. The surface temperature of fused quartz ceramic increases with the increase in the radiant heat flux of the quartz lamp array. When the input power is 5 kW, the maximum surface temperature of the sample can reach 1153 °C. However, the non-uniformity of the sample surface temperature also increases, reaching a maximum uncertainty of 12.28%. The research in this paper provides important theoretical guidance for the heat insulation design of ultra-high acoustic velocity aircraft. [ABSTRACT FROM AUTHOR]