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Incidence of Deliberate Self-Harm in Hong Kong Before and During the COVID-19 Pandemic: Population-Wide Retrospective Cohort Study
No full textBackground: COVID-19 ended on May 5, 2023, and since then Hong Kong reported increased mental distress, which was speculated to be from the policies implemented during the pandemic. Despite this, longitudinal surveillance of deliberate self-harm (DSH) incidences throughout the pandemic in Hong Kong remained insufficient.Objective: The objective of this study was to outline the changes in DSH incidences before and during the COVID-19 pandemic in Hong Kong, with respect to sex, age, and co-occurring mental health issues.Methods: A quasi-experiment was conducted using an interrupted time series design to estimate the impact of the pandemic on DSH-related emergency department (ED) visits. This design enabled the estimation of DSH-related ED visits based on prepandemic data from 2016 to 2019, assuming the pandemic had not occurred, and allowed for a comparison with observed DSH-related ED visits during the pandemic. The descriptive results were reported as the observed monthly DSH-related ED visits and observed incidence ratios during the pandemic. Afterwards, a negative binomial model was fitted to the prepandemic data (2016-2019) and adjusted for temporal trends, seasonality, and population variation to estimate the expected monthly DSH-related ED visits and adjusted incidence ratios (aIRs).Results: Between January 2016 and December 2022, a total of 31,893 DSH episodes were identified. Initial descriptive analysis showed a significant difference in demographic characteristics (sex) and clinical characteristics (death within 28 d, diagnoses of co-occurring mental health issues, public assistance pay code, and triage level). Subsequent interrupted time-series analysis demonstrated significantly increasing trends in comparison with the prepandemic period. As reported in the aIRs among young adult males (aIR in 2020=1.34, P=.002; 2021: aIR=1.94, PConclusions: The average annual DSH-related ED visits increased during the pandemic period. Therefore, there is a need to raise awareness for such vulnerable groups in Hong Kong to prepare for postpandemic spillover.</p
Combined cooling and power: Investigating the coupling effect between a microfluidic fuel cell and a heating chip
No full textMicrofluidic fuel cell (MFC) employs microfluidic electrolytes for reactant delivery, which is naturally suitable for combined cooling & power applications such as AI chips. However, this dual function has long been neglected in past literature. This work investigates the coupling effect between a MFC and a heating chip. The integrated system can not only remove the waste heat continuously but also leverage it to enhance electrochemical reactions, thereby improving both cooling efficiency and power output at the same time. To understand the in-depth coupling mechanism, various operation conditions are studied, including different electrolyte flow rates and heating modes. Results indicate that unlike conventional MFCs, the MFC performance under external heating is higher at lower flow rates, which is mainly benefited from the higher electrolyte temperature under this circumstance. For instance, at a constant heating power of 0.15 W/cm2 and a flow rate of 100 µL/min, the MFC achieves a peak power density of 27.3 mW/cm2, while it is only 16.6 at 1000 µL/min. Nevertheless, higher flow rates lead to better cooling effect, which can lower the chip temperature from 79.4°C to 54.0°C at 1000 µL/min, while it is only to 64.2°C at 100 µL/min. To improve the cooling effect of MFC at lower flow rates, both MFC scaling-up and MFC stacking have been investigated, of which the latter strategy exhibits much better performance in both cooling and power. To sum up, this work provides valuable insights into the design and optimization of microfluidic combined cooling & power system, highlighting its potential in addressing thermal & power challenges of next-generation AI chips
Promoting health behavioral intention through short videos: roles of audiovisual cross-modal correspondence in health communication
No full textPurpose: Health short videos are serving as a powerful tool for encouraging individuals to actively adopt healthier behaviors. The sensory cues applied in these videos can be useful for engaging peripheral processing and enhancing attitudes. While previous research has examined the effects of various single cues, this study features a pioneering attempt to explore the roles of audiovisual cross-modal correspondence, encompassing multisensory cues perceived through different modalities, in health communication. Design/methodology/approach: A 2 (color: warm/cool) × 2 (music tempo: fast/slow) between-subjects experiment was conducted to observe 120 participants’ responses to a health short video promoting eye health that was created using four different combinations of background color and background music tempo. Findings: It was found that the congruent color–tempo pairings, that is blue & slow and orange & fast, led to more positive attitudes toward the videos than the incongruent pairings, that is blue & fast and orange & slow. The effect of cross-modal correspondence on attitude was fully mediated by processing fluency, with gender acting as a moderator between the two variables. Furthermore, individuals’ attitudes toward a short video positively influenced their health behavioral intentions. Originality/value: These findings not only lend support to the theoretical framework of “multisensory cues-fluency-attitude-intention” chain for persuasion purposes but also have practical implications for creating effective health short videos
Gamification bolsters self-regulated learning, learning performance and reduces strategy decline in flipped classrooms: A longitudinal quasi-experiment
No full textFlipped classrooms, which foster active learning, are becoming more prevalent in higher education. Yet, many students struggle with self-regulated learning (SRL) skills and prefer traditional learning methods. The use of SRL relies on both students' motivation and skills but it is unclear how these skills evolve over time since many previous studies often overlook the temporal effects of interventions. To address these challenges, we introduced a gamified self-regulated flipped learning (GSRFL) approach. This approach integrates gamification elements and self-regulation supports, such as a learning analytics dashboard, to motivate and aid students' behaviors across three main SRL stages: planning, execution, and self-evaluation. We conducted a longitudinal quasi-experimental study with first-year university students to examine the impact on their SRL behaviors. The longitudinal study offers a considerable methodological advantage by providing detailed information about an intervention's impact over time. The experimental group (N = 76) utilized the GSRFL approach, while the control group (N = 75) employed the same self-regulated flipped learning approach but without gamification. Results showed that gamification significantly improved students' English learning achievement and overall SRL behaviors. Longitudinal observations revealed a positive main intervention effect on metacognitive monitoring behaviors, despite a natural decline in SRL behaviors over time. Gamification effectively moderated the decline of underutilized SRL strategies like goal setting and time management. These results underscore gamification's potential to enhance academic performance and promote SRL skills
Superior tribological performance of electrophoretically deposited multi-layer Ti3C2Tx coatings induced by a dynamically stable lubricating system
No full textDue to the superior tribological performance induced by their ability to form lubricious tribo-layer, multi-layer MXenes are considered promising next-generation solid lubricants. However, the formation mechanism of the tribo-layer and its connection with the frictional evolution have not yet been fully explored and understood. In this study, the tribological performance of electrophoretically deposited Ti3C2Tx coatings was assessed by reciprocating ball-on-disk tribometry. Under a contact pressure of 0.84 GPa, the MXene coating exhibited notable reductions in friction and wear rate by factors of 4.8 and 38, respectively. The detailed investigation of the wear tracks confirmed the formation of two different types of tribo-layers, namely a thin nano-porous and a thick densified tribo-layer, which helped to form a dynamically stable lubricating system thus inducing a superior solid lubrication performance. Their formation mechanisms were investigated through nanoscale microstructural and chemical analysis thus shedding light onto the correlation between the observed frictional behavior and the underlying tribo-layer formation process
Report of the 57th Annual Meeting of the Pacific Association of Pediatric Surgeons
Get PDFThe 57th annual meeting of the Pacific Association of Pediatric Surgeons was held from April 28th to May 2nd, 2024, at the Hong Kong Ocean Park Marriot Hotel in Hong Kong SAR, China. This year marks the first time that the PAPS Meeting was held in conjunction with the 27th Congress of the Asian Association of Pediatric Surgeons (AAPS) Meeting and the regional meeting of the World Federation of Associations of Pediatric Surgeons (WOFAPS). There were over 500 participants from 27 countries attending the meeting including travelers from India, Iran, Kuwait, Russia, and Saudi Arabia. This resulted in a conference defined by diverse opinions, shared learning, and networking.published_or_final_versio
Real-Time fMRI Neurofeedback Modulation of Dopaminergic Midbrain Activity in Young Adults With Elevated Internet Gaming Disorder Risk: Randomized Controlled Trial
No full textThis study provides preliminary evidence for real-time functional magnetic resonance imaging neurofeedback (rt-fMRI NF) as a potential intervention approach for internet gaming disorder (IGD). In a preregistered, randomized, single-blind trial, young individuals with elevated IGD risk were trained to downregulate gaming addiction–related brain activity. We show that, after 2 sessions of neurofeedback training, participants successfully downregulated their brain responses to gaming cues, suggesting the therapeutic potential of rt-fMRI NF for IGD</p
Knowledge-enhanced ontology-to-vector for automated ontology concept enrichment in BIM
No full textBuilding Information Modeling (BIM) relies on standardized ontologies like IfcOWL to address interoperability. However, the increasing complexity and diversity of construction information requirements demand automated enrichment of BIM ontologies, which is hindered by several factors, including complexity in ontology structure, scalability limitations, and domain-specific issues. Manual curation and maintenance of ontologies are labor-intensive and time-consuming, particularly as the scope of BIM projects expands. Despite these challenges, the construction industry lacks an effective automated approach for ontology concept enrichment. Thus, this study proposes a knowledge-enhanced ontology-to-vector (Keno2Vec) approach for automated BIM ontology concept enrichment, which can (1) encode ontology elements into meaningful and semantically rich embeddings by employing the BERT model to integrate both ontological information (names and labels) and external knowledge (definitions from authoritative knowledge bases), effectively addressing the domain expression specificity and complexity of BIM ontologies; and (2) provide a flexible framework that supports various downstream tasks of ontology concept enrichment by utilizing the resulting embeddings, thereby improving the task-specific adaptability and variability. Experimental results on datasets derived from the large-scale ifcOWL and two smaller BIM ontologies demonstrate that Keno2Vec significantly outperforms existing ontology embedding approaches in terms of accuracy and adaptability. For example, Keno2Vec achieves F1 scores on ifcOWL of nearly 87 % for subsumption prediction, 60 % for property identification, 95 % for membership recognition, and 100 % and 90 % for category-based and schema-based concept classification, respectively. Additional analysis highlights the potential of Keno2Vec for improving BIM ontology encoding and benefiting downstream applications.</p
Programmable Metamaterial for In-Plane Electromagnetic Wave Control in the Microwave Range
No full textTunable and programable devices hold a significant interest in electromagnetic (EM) engineering. A notable example is the programmable metasurfaces, which are quite powerful in controlling the phase front and steering beam of free-space waves. Similarly, managing in-plane EM waves on board is crucial for various applications. However, a programmable metamaterial (PMM) suitable for in-plane EM wave control is yet to be developed. Here, a PMM is presented that dynamically controls in-plane waves and is integrated on-boardly. The PMM is designed by incorporating metallic structures and tunable varactors. By biasing the varactors, a bulk module composed of an array of metamaterial unit cells can exhibit varied responses to incoming waves. As proof of concept, a PMM module for microwave control is fabricated and measured. In experiments, the PMM is successfully programmed to perform three distinct functions: wave splitting, Luneburg focusing, and wave differentiation, around the destination frequency (4.5 GHz). Although the PMM is dispersive and its bandwidth is somehow limited, its central frequency can be shifted in a dynamic range from 4 to 5 GHz. The proposed PMM resembles a miniaturized platform for reprogrammable in-plane wave control and manipulation, showing promise for realizing full wave operators, integrable computing, and deep learning devices.</p
Diffusion-based Deep Reinforcement Learning for Resource Management in Connected Construction Equipment Networks: A Hierarchical Framework
No full textWith the extensive adoption of information technology, tunnel construction is experiencing a rapid digital transformation. Integrating powerful direct communication among construction equipment (CE) facilitates real-time data exchange, promoting collaborative operations among CE. Concurrent execution of multiple construction procedures leads to a significant rise in the amount of CE and communication links, resulting in resource competition. However, this competition is aimed at enhancing collaboration. To address this inherently contradictory issue, we propose a hierarchical resource management framework and align communication quality of service (QoS) to construction efficiency using construction procedure coherence degree (CPCD) based on age of information (AoI). By formulating resource management as a stochastic optimization problem, a suitable online two-level deep reinforcement learning algorithm referred to as diffusion based soft actor critic (DSAC)-QMIX is designed to derive the radio resource allocation strategies. DSAC is responsible for orchestrating spectrum inter-fleets at the high-level, and QMIX makes the resource management and power control decision for each CE at the low-level. Simulation results validate the effectiveness of the DSAC-QMIX algorithm with comparable transmission rate, and show superior performance in terms of CPCD satisfaction compared with other benchmarks.</p