195 results on '"Qijin Cheng"'
Search Results
2. Effects of a Parent-Child Single-Session Growth Mindset Intervention on Adolescent Depression and Anxiety Symptoms: Protocol of a 3-Arm Waitlist Randomized Controlled Trial
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Shimin Zhu, Yuxi Hu, Ruobing Wang, Di Qi, Paul Lee, So Wa Ngai, Qijin Cheng, and Paul Wai Ching Wong
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Medicine ,Computer applications to medicine. Medical informatics ,R858-859.7 - Abstract
BackgroundDepression and anxiety are common mental health problems among adolescents worldwide. Extant research has found that intelligence, emotion, and failure-is-debilitating beliefs (fixed mindsets) are closely related to more depression and anxiety symptoms, hopelessness, and suicidality. Recent research also points to the importance of parental mindset, which can strongly influence children’s affect, behavior, and mental health. However, the effects of parent-child mindset interventions on a child’s internalizing problems have not yet been empirically examined. As recent evidence has shown the promise of single-session interventions in reducing and preventing youth internalizing problems, this study develops and examines a parent and child single-session intervention on mindsets of intelligence, failure, and emotion (PC-SMILE) to tackle depression and anxiety in young people. ObjectiveUsing a 3-arm randomized controlled trial, this study will examine the effectiveness of PC-SMILE in reducing depression and anxiety symptoms among children. We hypothesize that compared to the waitlist control group, the PC-SMILE group and child single-session intervention on mindsets of intelligence, failure, and emotion (C-SMILE) group will significantly improve child depression and anxiety (primary outcome) and significantly improve secondary outcomes, including children’s academic self-efficacy, hopelessness, psychological well-being, and parent-child interactions and relationships, and the PC-SMILE is more effective than the C-SMILE. MethodsA total of 549 parent-child dyads will be recruited from 8 secondary schools and randomly assigned to either the PC-SMILE intervention group, the C-SMILE intervention group, or the no-intervention waitlist control group. The 45-minute interventions include parent-version and child-version. Both parents and students in the PC-SMILE group receive the intervention. Students in C-SMILE group receive intervention and their parents will receive intervention after all follow-up ends. Students in 3 groups will be assessed at 3 time points, baseline before intervention, 2 weeks post intervention, and 3 months post intervention, and parents will be assessed in baseline and 3-month follow-up. The intention-to-treat principle and linear-regression-based maximum likelihood multilevel models will be used for data analysis. ResultsRecruitment started in September 2023. The first cohort of data collection is expected to begin in May 2024 and the second cohort will begin in September 2024. The final wave of data is expected to be collected by the end of the first quarter of 2025. The results are expected to demonstrate improved anxiety and depression among students assigned to the intervention condition, as well as the secondary outcomes compared to those in the control group. The efficacy and effectiveness of the intervention will be discussed. ConclusionsThis study is the first attempt to develop a web-based single-session intervention for students and their parents to enhance their well-being in Hong Kong and beyond, which potentially contributes to providing evidence-based recommendations for the implementation of brief digital parent-child interventions. International Registered Report Identifier (IRRID)PRR1-10.2196/63220
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- 2024
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3. Editorial for Special Issue 'Functional Graphene-Based Nanodevices'
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Qijin Cheng and Jian Zhou
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n/a ,Chemistry ,QD1-999 - Abstract
As a typical ultra-thin two-dimensional nanomaterial, graphene has many excellent properties, including, but not limited to, mechanical, optical, thermal and electrical properties [...]
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- 2024
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4. Examination of Web-Based Single-Session Growth Mindset Interventions for Reducing Adolescent Anxiety: Study Protocol of a 3-Arm Cluster Randomized Controlled Trial
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Shimin Zhu, Samson Tse, Ko Ling Chan, Paul Lee, Qijin Cheng, and Jessica Sun
- Subjects
Medicine ,Computer applications to medicine. Medical informatics ,R858-859.7 - Abstract
BackgroundAnxiety disorders are the most common mental disorders worldwide. In Hong Kong, 7% of adolescents are diagnosed with anxiety disorders, and 1 in every 4 secondary school students reports clinical-level anxiety symptoms. However, 65% of them do not access services. Long waitlists in public services, the high cost of private services, or the fear of being stigmatized can hinder service access. The high prevalence of anxiety and low intervention uptake indicate a pressing need to develop timely, scalable, and potent interventions suitable for adolescents. Single-session interventions (SSIs) have the potential to be scalable interventions for diagnosable or subclinical psychopathology in adolescents. Providing precise and context-adapted intervention is the key to achieving intervention efficacy. ObjectiveThis study aims to compare the effectiveness of three SSIs: single-session intervention of growth mindset on negative emotions (SIGMA), SSI of growth mindset of personality (SSI-GP), and active control, in reducing adolescent anxiety. MethodsAdolescents (N=549, ages 12-16 years) from secondary schools will be randomized to 1 of 3 intervention conditions: the SIGMA, SSI-GP, or active control. The implementation of each intervention is approximately 45 minutes in length. Adolescent participants will report anxiety symptoms (primary outcome), perceived control, hopelessness, attitude toward help-seeking, and psychological well-being at preintervention, the 2-week follow-up, and the 8-week follow-up. A pilot test has confirmed the feasibility and acceptability of SIGMA among adolescents. We hypothesized that SIGMA and SSI-GP will result in a larger reduction in anxiety symptoms than the control intervention during the posttest and 8-week follow-up period. We also predict that SIGMA will have a more significant effect than SSI-GP. We will use the intention-to-treat principle and linear regression-based maximum likelihood multilevel models for data analysis. ResultsThis study will be conducted from December 2022 to December 2023, with results expected to be available in January 2024. ConclusionsThis protocol introduces the implementation content and strategies of growth mindset SSIs (consists of 2 forms: SIGMA and SSI-GP) among school students. The study will provide evidence on the efficacy of different growth mindset SSIs for adolescent anxiety. It will also establish implementation strategies for self-administrative SSIs among school students, which can serve as a pioneer implementation of a scalable and self-accessible brief intervention to improve the well-being of young people. Trial RegistrationClinicalTrials.gov NCT05027880; https://clinicaltrials.gov/ct2/show/NCT05027880 International Registered Report Identifier (IRRID)PRR1-10.2196/41758
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- 2023
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5. Editorial: The Role of Media in Suicide and Self-Harm: Cross-Disciplinary Perspectives
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Qijin Cheng, Yukari Seko, and Thomas Niederkrotenthaler
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suicide ,self-harm ,mass media ,social media ,prevention ,Psychology ,BF1-990 - Published
- 2022
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6. High-Performance Graphene Nanowalls/Si Self-Powered Photodetectors with HfO2 as an Interfacial Layer
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Yuheng Shen, Yulin Li, Wencheng Chen, Sijie Jiang, Cheng Li, and Qijin Cheng
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hafnium oxide ,graphene nanowalls ,plasma-enhanced chemical vapor deposition ,photodetectors ,Chemistry ,QD1-999 - Abstract
Graphene/silicon (Si) heterojunction photodetectors are widely studied in detecting of optical signals from near-infrared to visible light. However, the performance of graphene/Si photodetectors is limited by defects created in the growth process and surface recombination at the interface. Herein, a remote plasma-enhanced chemical vapor deposition is introduced to directly grow graphene nanowalls (GNWs) at a low power of 300 W, which can effectively improve the growth rate and reduce defects. Moreover, hafnium oxide (HfO2) with thicknesses ranging from 1 to 5 nm grown by atomic layer deposition has been employed as an interfacial layer for the GNWs/Si heterojunction photodetector. It is shown that the high-k dielectric layer of HfO2 acts as an electron-blocking and hole transport layer, which minimizes the recombination and reduces the dark current. At an optimized thickness of 3 nm HfO2, a low dark current of 3.85 × 10−10, with a responsivity of 0.19 AW−1, a specific detectivity of 1.38 × 1012 as well as an external quantum efficiency of 47.1% at zero bias, can be obtained for the fabricated GNWs/HfO2/Si photodetector. This work demonstrates a universal strategy to fabricate high-performance graphene/Si photodetectors.
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- 2023
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7. Effectiveness of a Malaysian Media Intervention Workshop: Safe Reporting on Suicide
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Jane Tze Yn Lim, Qijin Cheng, Yin Ping Ng, Kai Shuen Pheh, Ravivarma Rao Panirselvam, Kok Wai Tay, Joanne Bee Yin Lim, Wen Li Chan, Amer Siddiq Amer Nordin, Hazli Zakaria, Sara Bartlett, Jaelea Skehan, Ying-Yeh Chen, Paul Siu Fai Yip, Shamsul Azhar Shah, and Lai Fong Chan
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Malaysian ,media ,workshop ,safe reporting ,suicide ,Psychology ,BF1-990 - Abstract
Background: Suicide remains an important cause of premature deaths and draws much media attention. However, unsafe reporting and portrayal of suicides by the media have been associated with increased risk of suicidal behavior. Current evidence suggests that media capacity-building could potentially prevent suicide. However, there are still knowledge gaps in terms of a lack of data on effective strategies for improving awareness and safe reporting of suicide-related media content. This study aims to investigate the effectiveness of a workshop conducted with members of the media community on the safe reporting of suicide-related content.Methods: An interventional single-arm pre and post pilot study was conducted on a sample of the Malaysian media community recruited through purposive and snowball sampling. The media safe reporting workshop was conducted by a suicide prevention expert with a media industry background. Thirty participants completed a self-reported evaluation questionnaire on their awareness and knowledge of reporting on suicide-related media content; before and after the interventional workshop.Results: There was a significant difference between the total scores before and after the intervention, with a large effect size. Post-intervention scores were significantly improved in 8 items, namely those related to the reporting of: (i) the content of any suicide note; (ii) headlines with methods of suicide; (iii) headlines with the location of suicide; (iv) cases of suspected suicide despite the unconfirmed cause of death; (v) suicide news to cater to readers’ interests; (vi) cause of suicide; (vii) details of the location of suicide; and (viii) the negative impact to media community when reporting suicide stories. In particular, there was an improvement in the majority of items for people from the media community with no lived experience of suicidal behavior.Conclusion: The media safe reporting workshop is a potentially effective intervention for improving awareness and knowledge measures relating to safe reporting on suicide among the media community, with a more pronounced effect in those without lived experience of suicidal behavior. Limitations in the sample size, generalizability, short-term evaluation, and lack of a control group warrant future larger, longer-term controlled, and more representative studies.
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- 2021
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8. Typology and Impact of YouTube Videos Posted in Response to a Student Suicide Crisis: Social Media Metrics and Content Analyses
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Qijin Cheng, Carrie Lui, Flora Wai Lam Ip, and Paul Siu Fai Yip
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Psychology ,BF1-990 - Abstract
BackgroundVideos relating to suicide are available on YouTube, but their characteristics and impacts have seldom been examined. ObjectiveThis study aimed to examine YouTube videos posted in response to a sudden spate of student suicides in Hong Kong during the 2015-2016 school year and evaluate the impacts of those videos. MethodsKeyword search was performed on YouTube, and relevant videos were identified. Video typology was examined through content analysis, specifically grouping the videos by who uploaded the videos, what presentation formats were used in the videos, whether the videos were originally created by the uploaders, and whether the videos disclosed the uploaders’ personal experiences with suicide. Impacts of the videos were assessed in terms of reach (measured by view count), engagement (measured by comment count), and insights (measured as to what extent the comments to each video could reveal personal suicide risk and attitude toward help-seeking). Statistical analysis was conducted to compare the impacts of different types of videos. The 7 most impactful videos that were originally created by the YouTubers were selected for further analysis. They were compared with 7 videos uploaded by the same YouTubers right before the student suicide videos and 7 right after the student suicide videos. The comparison focused on their impacts and the network structure of the comments to those videos. ResultsA total of 162 relevant YouTube videos were identified. They were uploaded by 7 types of stakeholders, and the most common format was one person talking to the camera. A total of 87.0% (141/162) of the videos were originally created by the uploaders and only 8.0% (13/162) of the videos disclosed uploader personal experiences with suicide. The uploader profiles being popular or top YouTubers and the video containing disclosure of the uploader’s personal experiences were found to be significantly correlated with greater impacts (P
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- 2021
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9. Understanding the Better Than Average Effect on Altruism
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Yunyu Xiao, Kelly Wong, Qijin Cheng, and Paul S. F. Yip
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Hong Kong ,altruism ,latent class analysis ,prosocial behavior ,better than average ,altruistic behaviors ,Psychology ,BF1-990 - Abstract
Prior research suggests that most people perceive themselves to be more altruistic than the average population, an observation known as the better-than-average (BTA) effect. Understanding the BTA effect carries significant public health implications, as self-perceived altruism is closely related to altruistic behaviors, which plays a significant role in individual and societal well-being. However, little is known about whether subpopulations with specific sociodemographic profiles are more likely to hold BTA altruistic self-perceptions, making it difficult to design targeted programs based on multiple sociodemographic characteristics to promote altruistic behaviors. This study addresses this gap by identifying the sociodemographic profiles of populations who are more likely to exhibit BTA effects on trait altruism. Data were derived from a representative sample of Hong Kong citizens (n = 1,185) in the 2017 Hong Kong Altruism Survey. A latent class analysis was performed using four domains of sociodemographic characteristics: sex, age, religion, and socioeconomic status. Multivariate multinomial logistic regressions were conducted to examine associations between class membership, BTA effect, and altruistic behaviors. The results yielded four classes of sociodemographic profiles. Middle-aged, Christian/Catholic, highly educated, and high-income individuals (Class 4, 17.8%) were most likely to exhibit BTA effects and behave altruistically; Class 3 (14.0%) were older, male, no/other religious belief, low education, and least likely to exhibit BTA effects and behave altruistically. Findings improve the understanding of the sociodemographic profiles of people showing BTA effects and facilitate targeted policy development to effectively promote altruism.
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- 2021
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10. A 24-hour online youth emotional support: Opportunities and challenges
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Paul YIP, Wai Leung CHAN, Qijin CHENG, Shirley CHOW, Siu Man HSU, Y.W. LAW, Billie LO, Ken NGAI, Kwai Yau WONG, Cynthia XIONG, and Tsz Kong YEUNG
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Public aspects of medicine ,RA1-1270 - Published
- 2020
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11. Single-Crystalline Metal Oxide Nanostructures Synthesized by Plasma-Enhanced Thermal Oxidation
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Bin Guo, Martin Košiček, Junchi Fu, Yazhou Qu, Guanhua Lin, Oleg Baranov, Janez Zavašnik, Qijin Cheng, Kostya (Ken) Ostrikov, and Uroš Cvelbar
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metal oxide nanostructures ,plasma-enhanced thermal oxidation ,growth mechanism ,material characterization ,nanostructure growth modelling ,Chemistry ,QD1-999 - Abstract
To unravel the influence of the temperature and plasma species on the growth of single-crystalline metal oxide nanostructures, zinc, iron, and copper foils were used as substrates for the study of nanostructure synthesis in the glow discharge of the mixture of oxygen and argon gases by a custom-made plasma-enhanced horizontal tube furnace deposition system. The morphology and microstructure of the resulting metal oxide nanomaterials were controlled by changing the reaction temperature from 300 to 600 °C. Experimentally, we confirmed that single-crystalline zinc oxide, copper oxide, and iron oxide nanostructures with tunable morphologies (including nanowires, nanobelts, etc.) can be successfully synthesized via such procedure. A plausible growth mechanism for the synthesis of metal oxide nanostructures under the plasma-based process is proposed and supported by the nanostructure growth modelling. The results of this work are generic, confirmed on three different types of materials, and can be applied for the synthesis of a broader range of metal oxide nanostructures.
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- 2019
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12. Stability of Hybrid Organic-Inorganic Perovskite CH3NH3PbBr3 Nanocrystals under Co-Stresses of UV Light Illumination and Temperature
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Weijie Guo, Nan Chen, Binbin Xu, Yijun Lu, Bin Li, Tingzhu Wu, Qijin Cheng, Yang Li, Jin Chen, Yue Lin, and Zhong Chen
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perovskite nanocrystals ,stability ,combined stresses ,electronic structure ,photophysical properties ,Chemistry ,QD1-999 - Abstract
Hybrid organic−inorganic metal halide perovskite nanocrystals (NCs) are among the candidates for color conversion materials in displays, especially in NC-based micro-light-emitting diode (micro-LED) displays. However, these NCs are still lacking long-term stability, which has hindered their large-scale applications. We mimic the working conditions, which include ultraviolet light illumination at 323 K and three different types of atmosphere (N2, vacuum, and air), respectively, to investigate the stability of CH3NH3PbBr3 NCs embedded in the polyvinylidene fluoride matrix. X-ray diffraction results indicate the generation of NH4Pb2Br5, which is produced from the encapsulated CH3NH3PbBr3 NCs in all three atmospheres, and the decomposition generates a large amount of accompanying interface defects at the surface area of NCs, resulting in the significant decrease of the photoluminescence (PL) intensity. This work highlights the stability-related mechanism of CH3NH3PbBr3 NCs under combined external stresses that mimic operating conditions. In addition, this work also suggests a new method for conducting aging tests and contributes to developing effective routes towards higher stability of perovskite NCs.
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- 2019
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13. Media effects on suicide methods: A case study on Hong Kong 1998-2005.
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Qijin Cheng, Feng Chen, and Paul S F Yip
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Medicine ,Science - Abstract
BACKGROUND:Previous studies have suggested that mass media's reports of new suicide methods will increase suicides using the same method. The same pattern seems not to apply to a conventional suicide method, unless it was used by a celebrity. OBJECTIVE:1) to examine media effects on both new and non-new suicide methods during 1998 and 2005 in Hong Kong (HK), when a new method by burning charcoal (CB suicide) was spreading in the region. 2) to examine how CB competed with non-CB methods in terms of media coverage and "recruiting" suicidal persons in the socio-economic context. METHODS:A self- and mutual- exciting process model was fitted to the data, adjusting for divorce rate, unemployment rate, and property price index. Breaking the whole period into onset, peak, and post-peak stages, the model was fitted again to examine the differences. RESULTS:Comparable copycat effects were found on both CB and non-CB suicide news. The only cross-method media effects were found in the onset stage when non-CB suicide news showed suppressing effect on CB suicides. CB suicides reported a significant self-excitation effect. A higher divorce rate and lower property price index were associated with significantly more suicides incidences and more suicide news. CONCLUSIONS:The emerging of CB suicide method did not substitute media coverage of non-CB suicide in HK. Media effects in this case were not limited to new suicide method or celebrity suicide. The effects were further fueled by adverse socio-economic conditions.
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- 2017
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14. Information Accessibility of the Charcoal Burning Suicide Method in Mainland China.
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Qijin Cheng, Shu-Sen Chang, Yingqi Guo, and Paul S F Yip
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Medicine ,Science - Abstract
There has been a marked rise in suicide by charcoal burning (CB) in some East Asian countries but little is known about its incidence in mainland China. We examined media-reported CB suicides and the availability of online information about the method in mainland China.We extracted and analyzed data for i) the characteristics and trends of fatal and nonfatal CB suicides reported by mainland Chinese newspapers (1998-2014); ii) trends and geographic variations in online searches using keywords relating to CB suicide (2011-2014); and iii) the content of Internet search results.109 CB suicide attempts (89 fatal and 20 nonfatal) were reported by newspapers in 13 out of the 31 provinces or provincial-level-municipalities in mainland China. There were increasing trends in the incidence of reported CB suicides and in online searches using CB-related keywords. The province-level search intensities were correlated with CB suicide rates (Spearman's correlation coefficient = 0.43 [95% confidence interval: 0.08-0.68]). Two-thirds of the web links retrieved using the search engine contained detailed information about the CB suicide method, of which 15% showed pro-suicide attitudes, and the majority (86%) did not encourage people to seek help.The incidence of CB suicide was based on newspaper reports and likely to be underestimated.Mental health and suicide prevention professionals in mainland China should be alert to the increased use of this highly lethal suicide method. Better surveillance and intervention strategies need to be developed and implemented.
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- 2015
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15. The Preparation and Microstructure of Nanocrystal 3C-SiC/ZrO2 Bilayer Films
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Chao Ye, Guang Ran, Wei Zhou, Yazhou Qu, Xin Yan, Qijin Cheng, and Ning Li
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3C-SiC/ZrO2 film ,thin film ,nanomaterials ,PECVD ,Chemistry ,QD1-999 - Abstract
The nanocrystal 3C-SiC/ZrO2 bilayer films that could be used as the protective coatings of zirconium alloy fuel cladding were prepared on a single-crystal Si substrate. The corresponding nanocrystal 3C-SiC film and nanocrystal ZrO2 film were also dividedly synthesized. The microstructure of nanocrystal films was analyzed by grazing incidence X-ray diffraction (GIXRD) and cross-sectional transmission electron microscopy (TEM). The 3C-SiC film with less than 30 nm crystal size was synthesized by Plasma Enhanced Chemical Vapor Deposition (PECVD) and annealing. The corresponding formation mechanism of some impurities in SiC film was analyzed and discussed. An amorphous Zr layer about 600 nm in width was first deposited by magnetron sputtering and then oxidized to form a nanocrystal ZrO2 layer during the annealing process. The interface characteristics of 3C-SiC/ZrO2 bilayer films prepared by two different processes were obviously different. SiZr and SiO2 compounds were formed at the interface of 3C-SiC/ZrO2 bilayer films. A corrosion test of 3C-SiC/ZrO2 bilayer films was conducted to qualitatively analyze the surface corrosion resistance and the binding force of the interface.
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- 2017
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16. Suicide contagion: a systematic review of definitions and research utility.
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Qijin Cheng, Hong Li, Vincent Silenzio, and Eric D Caine
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Medicine ,Science - Abstract
Despite the common use of contagion to analogize the spread of suicide, there is a lack of rigorous assessment of the underlying concept or theory supporting the use of this term. The present study aims to examine the varied definitions and potential utility of the term contagion in suicide-related research.100 initial records and 240 reference records in English were identified as relevant with our research objectives, through systematic literature screening. We then conducted narrative syntheses of various definitions and assessed their potential value for generating new research.20.3% of the 340 records used contagion as equivalent to clustering (contagion-as-cluster); 68.5% used it to refer to various, often related mechanisms underlying the clustering phenomenon (contagion-as-mechanism); and 11.2% without clear definition. Under the category of contagion-as-mechanism, four mechanisms have been proposed to explain how suicide clusters occurred: transmission (contagion-as-transmission), imitation (contagion-as-imitation), contextual influence (contagion-as-context), and affiliation (contagion-as-affiliation). Contagion-as-cluster both confounds and constrains inquiry into suicide clustering by blending proposed mechanism with the phenomenon to be studied. Contagion-as-transmission is, in essence, a double or internally redundant metaphor. Contagion-as-affiliation and contagion-as-context involve mechanisms that are common mechanisms that often occur independently of apparent contagion, or may serve as a facilitating background. When used indiscriminately, these terms may create research blind spots. Contagion-as-imitation combines perspectives from psychology, sociology, and public health research and provides the greatest heuristic utility for examining whether and how suicide and suicidal behaviors may spread among persons at both individual and population levels.Clarifying the concept of "suicide contagion" is an essential step for more thoroughly investigating its mechanisms. Developing a clearer understanding of the apparent spread of suicide-promoting influences can, in turn, offer insights necessary to build the scientific foundation for prevention and intervention strategies that can be applied at both individual and community levels.
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- 2014
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17. Monolayer WS2 Nanosheets Passivated with HfO2 for Enhanced Photodetectors
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Jintao Yuan, Shangtong Zhou, Bohan Xiao, Lingjie Bao, Zikang Ai, Yuheng Shen, Guang Ran, and Qijin Cheng
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General Materials Science - Published
- 2023
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18. High‐Brightness GaN‐Based Blue Light‐Emitting Diodes Using AlON Buffer Layer on 4 In.‐Patterned Sapphire Substrate: Low‐Dislocation‐Defect Epitaxy, Growth Mechanisms, and Higher Device Performance
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Minghang Li, Wencheng Chen, Jiasheng Zhang, Shuming Bai, Jiarong Zeng, Xueliang Zhu, Kelvin H. L. Zhang, Qijin Cheng, and Kostya (Ken) Ostrikov
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General Materials Science ,Condensed Matter Physics - Published
- 2023
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19. A Fast Self‐Powered Solar‐Blind Ultraviolet Photodetector Realized by Ga 2 O 3 /GaN PIN Heterojunction with a Fully Depleted Active Region
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Wencheng Chen, Xiangyu Xu, Minghang Li, Siliang Kuang, Kelvin H. L. Zhang, and Qijin Cheng
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Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials - Published
- 2023
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20. Examination of Web-Based Single-Session Growth Mindset Interventions for Reducing Adolescent Anxiety: Study Protocol of a 3-Arm Cluster Randomized Controlled Trial (Preprint)
- Author
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Shimin Zhu, Samson Tse, Ko Ling Chan, Paul Lee, Qijin Cheng, and Jessica Sun
- Abstract
BACKGROUND Anxiety disorders are the most common mental disorders worldwide. In Hong Kong, 7% of adolescents are diagnosed with anxiety disorders, and 1 in every 4 secondary school students reports clinical-level anxiety symptoms. However, 65% of them do not access services. Long waitlists in public services, the high cost of private services, or the fear of being stigmatized can hinder service access. The high prevalence of anxiety and low intervention uptake indicate a pressing need to develop timely, scalable, and potent interventions suitable for adolescents. Single-session interventions (SSIs) have the potential to be scalable interventions for diagnosable or subclinical psychopathology in adolescents. Providing precise and context-adapted intervention is the key to achieving intervention efficacy. OBJECTIVE This study aims to compare the effectiveness of three SSIs: single-session intervention of growth mindset on negative emotions (SIGMA), SSI of growth mindset of personality (SSI-GP), and active control, in reducing adolescent anxiety. METHODS Adolescents (N=549, ages 12-16 years) from secondary schools will be randomized to 1 of 3 intervention conditions: the SIGMA, SSI-GP, or active control. The implementation of each intervention is approximately 45 minutes in length. Adolescent participants will report anxiety symptoms (primary outcome), perceived control, hopelessness, attitude toward help-seeking, and psychological well-being at preintervention, the 2-week follow-up, and the 8-week follow-up. A pilot test has confirmed the feasibility and acceptability of SIGMA among adolescents. We hypothesized that SIGMA and SSI-GP will result in a larger reduction in anxiety symptoms than the control intervention during the posttest and 8-week follow-up period. We also predict that SIGMA will have a more significant effect than SSI-GP. We will use the intention-to-treat principle and linear regression-based maximum likelihood multilevel models for data analysis. RESULTS This study will be conducted from December 2022 to December 2023, with results expected to be available in January 2024. CONCLUSIONS This protocol introduces the implementation content and strategies of growth mindset SSIs (consists of 2 forms: SIGMA and SSI-GP) among school students. The study will provide evidence on the efficacy of different growth mindset SSIs for adolescent anxiety. It will also establish implementation strategies for self-administrative SSIs among school students, which can serve as a pioneer implementation of a scalable and self-accessible brief intervention to improve the well-being of young people. CLINICALTRIAL ClinicalTrials.gov NCT05027880; https://clinicaltrials.gov/ct2/show/NCT05027880 INTERNATIONAL REGISTERED REPORT PRR1-10.2196/41758
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- 2022
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21. Change in suicidal ideation and associated factors among young adults in Hong Kong from 2018 to 2019: a latent transition analysis
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Qijin Cheng, Ted C. T. Fong, and Paul S. F. Yip
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Adult ,Male ,medicine.medical_specialty ,Health (social science) ,Social Psychology ,Epidemiology ,Psychological distress ,Person-centered approach ,Person-centered therapy ,Suicidal Ideation ,Young Adult ,Risk Factors ,SIDAS ,Prevalence ,medicine ,Humans ,Measurement invariance ,Young adult ,Suicidal ideation ,Original Paper ,Help-seeking behaviors ,Public health ,Suicide ,Psychiatry and Mental health ,Hong Kong ,Latent transition analysis ,Female ,medicine.symptom ,Psychology ,Latent class ,Clinical psychology - Abstract
Purpose Suicide in young adulthood is a vital public health concern. There have been few systematic studies that examined the prevalence and transition of suicidal ideation classes in young adults and the factors associated with the transition. Methods This two-wave survey recruited 1269 young adults (Mean age = 24.0 years, 70.1% males) in Hong Kong. The participants completed the Suicidal Ideation Attributes Scale, Chinese Health Questionnaire, and help-seeking behaviors in 2018 and 2019. Latent profile analysis was used to classify the participants into latent classes of suicidal ideation with substantive checking under the 3-step approach. Latent transition analysis with measurement invariance examined the transition among the latent classes from 2018 to 2019 and the associations with help-seeking behaviors and change in psychological distress. Results Three latent classes of suicidal ideation were identified and over two-thirds of the participants belonged to the Low-risk class with minimal suicidal ideation. The prevalence of the High-risk class dropped from 10.2 to 7.2%, while that of the Moderate-risk class remained stable from 2018 to 2019. Increases in psychological distress predicted higher probabilities to remain at or transit into more risky classes. Engagement in help-seeking behaviors showed differential transitions in suicidal ideation across time. Conclusion The findings suggest three latent classes of suicidal ideation with distinct profiles among the young adults. Deterioration in psychological distress showed a temporal effect on worsening of suicidal ideation over a 1-year period. Future studies should elucidate the comparative effectiveness of help-seeking behaviors via online and offline channels. Supplementary Information The online version contains supplementary material available at 10.1007/s00127-021-02203-9.
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- 2021
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22. Suicide Research in Mainland China, Hong Kong, and Macau Over Three Decades
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Xingzhou Zhang, Paul S. F. Yip, Qijin Cheng, and Carrie S. M. Lui
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Mainland China ,biology ,Rapid expansion ,Research findings ,Suicide prevention ,030227 psychiatry ,Suicide death ,03 medical and health sciences ,Psychiatry and Mental health ,0302 clinical medicine ,Suicide methods ,Political science ,Toll ,biology.protein ,030212 general & internal medicine ,Social science ,China - Abstract
Abstract. Background: China accounts for 15% of the global suicide death toll, yet suicide research efforts in the country are not well known by international colleagues. Aims: We aimed to outline the development of suicide research in China, appraise research findings, and identify key contributors. Method: English and Chinese research publication databases were systematically searched and relevant papers were reviewed. Chinese and English publications were compared. Results: There are almost 10 times more Chinese publications than English ones. The research focuses of and key contributors to the Chinese and English literature exhibit more differences than commonalities. The field experienced rapid expansion in the new millennium with more and higher quality publications and more funding support. Psychosocial-oriented perspectives guided most of the papers. Poisoning by pesticide as a suicide method and youth as a subpopulation group received the most research attention. Limitations: The scoping review does not provide in-depth syntheses on specific topics and does not include more recent publications. Conclusion: Research on suicide in China has been actively carried out during the 30-year period we reviewed, which might have contributed to suicide prevention in China. Research gaps identified by the review should be addressed to sustain the achievements.
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- 2021
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23. Who seeks help online? Comparing online and offline help-seeking preferences amongst youths with suicidal ideation
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Milton Chan, Qijin Cheng, Kelly Wong, Christian S. Chan, Clifford Wong, Cynthia Xiong, and Paul S. F. Yip
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Adult ,Online and offline ,Adolescent ,media_common.quotation_subject ,Applied psychology ,Embarrassment ,Suicidal Ideation ,Young Adult ,03 medical and health sciences ,Social support ,Help-Seeking Behavior ,0302 clinical medicine ,Surveys and Questionnaires ,medicine ,Humans ,Suicidal ideation ,media_common ,Internet ,business.industry ,Social Support ,Mental health ,Help-seeking ,030227 psychiatry ,Suicide ,Psychiatry and Mental health ,Clinical Psychology ,Distress ,Mental Health ,Hong Kong ,The Internet ,medicine.symptom ,business ,Psychology ,030217 neurology & neurosurgery - Abstract
Background : Research consistently report an inverse relationship between suicide risk and help-seeking. The increasingly available internet-based support potentially offers an attractive alternative to traditional forms of assistance. The study compared the characteristics of suicidal youths in Hong Kong and their online and offline help-seeking behaviours. Methods : Participants (N = 1214, age-range = 15–24 years) responded to the anonymous 2018 Hong Kong Online Survey on Youth Mental Health and Internet Usage. Respondents with suicidal thoughts were classified into those who sought help online and offline, or online only (“online-help”); those who sought help offline only (“offline-help”); and those who never sought help (“no-help”). They responded to questions concerning mental health, perception towards online support, internet use, help sources, and demographic information. Results : The online-help group differed significantly from other groups, with greater suicidal ideation, distress, risk behaviours, and spent more time online for non-work-related purposes. Their perceived benefits of online support include anonymity, avoiding embarrassment, and social support. They are more likely to seek help from a combination of informal and formal sources. Limitations : No data on whether participants sought help online or offline first, and their current treatment status is available. Our study adopted conveniences sampling, and few respondents have sought help online exclusively. Conclusion : Online support offers an alternate way of engaging at-risk youths. Future clinical practice should consider online platforms as a complement, rather than a replacement, of offline platforms.
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- 2021
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24. Measuring Online Social Support: Development and Validation of a Short Form for Chinese Adolescents
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Ziyao Zhou and Qijin Cheng
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China ,Adolescent ,Psychometrics ,Surveys and Questionnaires ,Health, Toxicology and Mutagenesis ,Public Health, Environmental and Occupational Health ,Humans ,Reproducibility of Results ,adolescent ,social support ,online social support ,confirmatory factor analysis ,scale validation ,cross-validation ,Factor Analysis, Statistical - Abstract
Supportive interactions on social media have great potential to benefit adolescents’ development. However, there is no instrument to measure online social support (OSS) in China. The study aimed to develop and validate a Chinese short version of the Online Social Support Scale (OSSS). The original scale was translated into Chinese through multiple forward and backward translation protocols. The calibration sample (N = 262) was used to select items and test the reliability, validity, and internal structure of the short form. The cross-validation sample (N = 267) was then used to assess measurement invariance by multigroup confirmatory factor analysis and examine criterion validity based on its relationships with life satisfaction, depression, and time on social media. The 20-item Chinese short version of OSSS (OSSS-CS) includes four factors: esteem/emotional support, social companionship, informational support, and instrumental support. Our results suggest that the OSSS-CS has high internal consistency, construct validity, and criterion validity. Furthermore, evidence of partial cross-validity demonstrated invariance of the variance–covariance matrices, factor structure, factor loadings, and factor variance across independent samples. The results also revealed that the original OSSS could be replicated across cultures. Finally, the short form developed in the study can be used as a reliable and valid measure of online social support among the Chinese adolescent population.
- Published
- 2022
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25. Direct Growth of Graphene Nanowalls on Inverted Pyramid Silicon for Schottky Junction Solar Cells
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Kelvin H. L. Zhang, Qijin Cheng, Junchi Fu, Ling Zhang, Li Shuai, and Feifei Huang
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Materials science ,Silicon ,business.industry ,Graphene ,Schottky barrier ,Energy Engineering and Power Technology ,chemistry.chemical_element ,Inverted pyramid ,law.invention ,chemistry ,law ,Materials Chemistry ,Electrochemistry ,Chemical Engineering (miscellaneous) ,Optoelectronics ,Electrical and Electronic Engineering ,business - Published
- 2021
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26. High-rate growth of gallium oxide films by plasma-enhanced thermal oxidation for solar-blind photodetectors
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Tong Su, Bohan Xiao, Zikang Ai, Lingjie Bao, Wencheng Chen, Yuheng Shen, Qijin Cheng, and Kostya (Ken) Ostrikov
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General Physics and Astronomy ,Surfaces and Interfaces ,General Chemistry ,Condensed Matter Physics ,Surfaces, Coatings and Films - Published
- 2023
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27. Learning from various labeling strategies for suicide-related messages on social media: An experimental study.
- Author
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Tong Liu 0010, Qijin Cheng, Christopher M. Homan, and Vincent M. B. Silenzio
- Published
- 2017
28. Online Peer-Support Group’s Role in Addressing Filipino Domestic Workers’ Social Support Needs: Content and Social Media Metrics Analysis
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Qijin Cheng and Christine Vicera
- Subjects
Self-Help Groups ,Communications Media ,Health, Toxicology and Mutagenesis ,Public Health, Environmental and Occupational Health ,Humans ,Social Support ,migrant domestic worker ,wellbeing ,mental health ,social support ,peer support ,online ,social media ,Facebook ,Social Media ,Peer Group - Abstract
The study aimed to examine what types of social support a prominent online peer support group has provided to Filipino domestic workers (FDWs) in Hong Kong (HK), how impactful each type of support was, and to what extent the support could address group members’ expressed needs. Posts published from 1 September 2021 to 31 December 2021 in one of the largest online peer-support groups for FDWs in HK and their meta-data were extracted from Facebook. Thematic content analysis was performed to extract relevant information from the posts. Descriptive statistical analysis on the social media metrics was conducted to measure post impacts. A total of 599 posts published over the study period can be categorized to provide informational (76.67%), emotional (33.56%), and instrumental support (13.52%). Posts including emotional support were often more impactful. A total of 58 posts responded to requests explicitly expressed by individual FDWs, of which 13 required external resources. The online peer-support group acts as a new channel to raise FDWs’ awareness of important issues related to their well-being, to encourage and facilitate them to seek formal and informal help, and to keep them emotionally attended to. Formal support services should recognize and collaborate with them and support their long-term sustainability.
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- 2022
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29. Growth and application of MoSe2 in solar cells
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Jintao Yuan, Zikang Ai, Meng Yu, Ruiming Huang, and Qijin Cheng
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Statistical and Nonlinear Physics ,Condensed Matter Physics - Abstract
MoSe2 from monolayer to bulk phase can realize the transition from a direct bandgap semiconductor to an indirect bandgap semiconductor. Its bandgap varies between 1.1 and 1.55 eV, which matches the solar spectral range, so Si-based heterojunction solar cells with MoSe2 as an active layer have great significance in the development of low-cost, high-efficiency and high-flexibility photovoltaic devices. In this work, MoSe2 thin films were synthesized by chemical vapor deposition using MoO3 and Se powders as precursor sources. The effects of different process parameters (Se source temperature, Mo source temperature, growth time, carrier gas flow rate and hydrogen ratio) on the synthesis of MoSe2 thin films were systematically investigated. The optimized experimental parameters were determined as follows: the molybdenum source temperature of 800[Formula: see text], the selenium source 20 cm away from molybdenum source, the growth time of 10 min, the carrier gas flow rate of 60 sccm, the hydrogen ratio of 10%. Then MoSe2/Si heterojunction solar cells were constructed via wet chemical transfer. The open-circuit voltage, short-circuit current density, filling factor and photovoltaic conversion efficiency of the fabricated solar cells were 0.19 V, 5.71 mA/cm2, 30.47% and 0.33%, respectively. Main factors affecting the photovoltaic performance of the MoSe2/Si solar cells have also been discussed. This work is very helpful for the development of MoSe2 material and relevant application in the field of solar cells.
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- 2022
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30. Applying text mining methods to suicide research
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Carrie S. M. Lui and Qijin Cheng
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050103 clinical psychology ,Computer science ,Poison control ,computer.software_genre ,Suicide prevention ,Suicidal Ideation ,03 medical and health sciences ,0302 clinical medicine ,Text mining ,Data Mining ,Humans ,0501 psychology and cognitive sciences ,Social media ,Suicide Risk ,Natural Language Processing ,Data source ,Information retrieval ,business.industry ,Document classification ,05 social sciences ,Public Health, Environmental and Occupational Health ,030227 psychiatry ,Suicide ,Psychiatry and Mental health ,Clinical Psychology ,Content analysis ,business ,Social Media ,computer - Abstract
OBJECTIVE To introduce the research methods of computerized text mining and its possible applications in suicide research and to demonstrate the procedures of applying a specific text mining area, document classification, to a suicide-related study. METHOD A systematic search of academic papers that applied text mining methods to suicide research was conducted. Relevant papers were reviewed focusing on their research objectives and sources of data. Furthermore, a case of using natural language processing and document classification methods to analyze a large amount of suicide news was elaborated to showcase the methods. RESULTS Eighty-six papers using text mining methods for suicide research have been published since 2001. The most common research objective (72.1%) was to classify which documents exhibit suicide risk or were written by suicidal people. The most frequently used data source was online social media posts (45.3%), followed by e-healthcare records (25.6%). For the news classification case, the top three classifiers trained for classification tasks achieved 84% or higher accuracy. CONCLUSIONS Computerized text mining methods can help to scale up content analysis capacity and efficiency and uncover new insights and perspectives for suicide research.
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- 2021
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31. Optimizing the Electronic Structure of In2O3 through Mg Doping for NiO/In2O3 p–n Heterojunction Diodes
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Jiaye Zhang, Zhenni Yang, Xiangyu Xu, Irene Azaceta, Qijin Cheng, Leonardo Lari, Yuheng Gong, Kelvin H. L. Zhang, and Vlado K. Lazarov
- Subjects
010302 applied physics ,Free electron model ,Materials science ,business.industry ,Band gap ,Doping ,Non-blocking I/O ,Heterojunction ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,Depletion region ,0103 physical sciences ,Breakdown voltage ,Optoelectronics ,General Materials Science ,0210 nano-technology ,business ,Diode - Abstract
In2O3 is a wide bandgap oxide semiconductor, which has the potential to be used as an active material for transparent flexible electronics and UV photodetectors. However, the high concentration of unintentional background electrons existing in In2O3 makes it hard to be modulated by the electric field or form p-n heterojunctions with a sufficient band-bending width at the interface. In this work, we report the reduction of the background electrons in In2O3 by Mg doping (Mg-In2O3) and thereby improve the device performance of p-n diodes based on the NiO/Mg-In2O3 heterojunction. In particular, Mg doping compensates the free electrons in In2O3 and reduces the electron concentration from 1.7 × 1019 cm-3 without doping to 1.8 × 1017 cm-3 with 5% Mg doping. Transparent p-n heterojunction diodes were fabricated based on p-type NiO and n-type Mg-In2O3. The device performance was considerably enhanced by Mg doping with a high rectification ratio of 3 × 104 and a remarkable high breakdown voltage of >20 V. High-resolution X-ray photoelectron spectroscopy was used to investigate the interfacial electronic structure between NiO and Mg-In2O3, revealing a type II band alignment with a valence band offset of 1.35 eV and a conduction band offset of 2.15 eV. A large built-in potential of 0.98 eV was found for the undoped In2O3 but decreased to 0.51 eV for 5% Mg doping of In2O3. The NiO/Mg-In2O3 diodes with an improved rectification ratio and wider depletion region provide the possibility of achieving photodetectors with rapid photoresponse.
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- 2020
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32. Evaluation of the sp3/sp2 ratio of DLC films by RF-PECVD and its quantitative relationship with optical band gap
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Song He, Hongxun Sheng, Qijin Cheng, Chao Chen, Songsheng Zheng, and Wenwen Xiong
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Materials science ,Band gap ,Analytical chemistry ,Energy Engineering and Power Technology ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,law.invention ,Inorganic Chemistry ,symbols.namesake ,X-ray photoelectron spectroscopy ,Plasma-enhanced chemical vapor deposition ,law ,Solar cell ,Materials Chemistry ,Fourier transform infrared spectroscopy ,Absorption (electromagnetic radiation) ,Renewable Energy, Sustainability and the Environment ,Process Chemistry and Technology ,Organic Chemistry ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,Ceramics and Composites ,symbols ,0210 nano-technology ,Raman spectroscopy ,Visible spectrum - Abstract
DLC has been attractive as semiconductor materials for solar cell due to its biological friendliness, flexible microstructures, and especially its tunable band gap. In order to fabricate high-efficiency multiband gap solar cell, it is important to control the sp3/ sp2 bonds ratio of DLC film corresponding to optical band gap (Eg). There are many references reporting the relations among the fabrication conditions, Eg, sp3/sp2, and ID/IG. However, a more comprehensive database is needed for controllable fabrication. Especially, the quantitative relationship of sp3/sp2 ratio to Eg of DLC film by PECVD is unclear. In this paper, 36 sets of DLC films were fabricated by RF-PECVD. Characterization methods of XPS, Raman spectroscopy, and IR absorption have been used to determine the sp3/sp2 ratio of DLC films. UV/visible light absorption method has applied to evaluate Eg. The Eg obtained is in the range 1.45–3.0 eV. Our results agree well with the references. The XPS spectra gives a linear relationship as Eg = − 0.161 (± 0.136) + 26.095 (± 1.704) · {sp3(XPS)/sp2}, the Raman spectra shows a linear function that Eg = 1.327 (± 0.046) + 0.428 (± 0.036) · (ID/IG), as well as the FTIR analysis demonstrates that Eg = − 0.492 (± 0.093) + 0.464 (± 0.044) · {sp3(FTIR)/sp2}.
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- 2020
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33. Growth of MoS2 and metal back electrode-dependent performance of MoS2/Si heterojunction solar cells
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Zikang Ai, Jintao Yuan, Ruiming Huang, Meng Yu, and Qijin Cheng
- Subjects
General Materials Science - Abstract
In this work, MoS2 thin films were successfully synthesized by chemical vapor deposition (CVD) using MoO3 and sulfur powders as precursor sources. The effect of the MoO3 dosage and heating temperature on the quality of the synthesized MoS2 films are investigated and a detailed reaction mechanism is proposed to interpret the obtained experimental result. Furthermore, we have studied the influence of different metal back electrodes (including Ag and Au) on the photovoltaic performance of the fabricated MoS2/Si heterojunction solar cell. It is shown that, in comparison with the solar cell using Au as a metal back electrode, the solar cell using Ag as a metal back electrode has poor photovoltaic performance with the appearance of the S-type shape in the measured current density-voltage curve. Finally, numerical simulation based on AFORS-HET software has been carried out to investigate the photovoltaic performance of the [Formula: see text]-MoS2/[Formula: see text]-Si heterojunction solar cell under different work functions of the metal back electrode. The result of numerical simulation is consistent with our experiential result in the trend. This work is highly relevant to the development of transition metal dichalcogenides in the application of solar cells.
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- 2022
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34. Editorial: The Role of Media in Suicide and Self-Harm: Cross-Disciplinary Perspectives
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Thomas Niederkrotenthaler, Yukari Seko, and Qijin Cheng
- Subjects
General Psychology - Abstract
[p.1]: Editorial on the Research Topic The Role of Media in Suicide and Self-Harm: Cross-Disciplinary Perspectives Suicide and self-harm are complex, multifaceted, and simultaneously personal and social phenomena. While what motivates a person to engage in these acts cannot be reduced to a single factor, the media's role as a shaper and conduit of meanings has attracted considerable scholarly and practitioner attention. Although the mass media has been, and will doubtlessly continue to play a key role in shaping public attitudes and behaviors toward suicide and self-harm, the user-generated media has dramatically diversified our opportunities to encounter and interact with media content featuring these behaviors.
- Published
- 2022
35. A modified CVD method for the synthesis of monolayer MoS2 and photoelectric improvement by HfO2 passivation
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Zikang Ai, Lingjie Bao, Bohan Xiao, Jintao Yuan, Wenfeng Li, Weiyi Lin, Cheng Li, and Qijin Cheng
- Subjects
Mechanics of Materials ,Mechanical Engineering ,General Materials Science ,Bioengineering ,General Chemistry ,Electrical and Electronic Engineering - Abstract
Molybdenum disulfide (MoS2) is an emerging class of new materials with a wide range of potential practical applications. However, the uncontrollability of monolayer MoS2 synthesized by traditional chemical vapor deposition method and the low responsivity of MoS2 photodetectors limit its further development in the field of photoelectric detection. To achieve controlled growth of monolayer MoS2 and construct MoS2 photodetectors with a high responsivity, we propose a novel single crystal growth strategy of high-quality MoS2 by controlling the Mo to S vapor ratio near the substrate, and deposit a layer of hafnium oxide (HfO2) on the surface of MoS2 to enhance the performance of the pristine metal-semiconductor-metal structure photodetector. At a reverse bias of 8 V, the HfO2 passivated MoS2 photodetector features an extremely high responsivity of 1201 AW − 1 , a response time of around 0.5 s, and a detectivity of 7.7 × 10 11 Jones . Meanwhile, we deeply investigate the effect of the HfO2 layer on the performance of the fabricated MoS2 photodetector and propose a physical mechanism to interpret the obtained experiment results. These results might facilitate a better understanding on the performance modulation of the MoS2 photodetectors and accelerate the development of MoS2-based optoelectronic devices.
- Published
- 2023
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36. Uncovering sample heterogeneity in gaming and social withdrawal behaviors in adolescent and young adult gamers in Hong Kong
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Ted C.T. Fong, Qijin Cheng, C.Y. Pai, Isabelle Kwan, Clifford Wong, Sing-Hang Cheung, and Paul S.F. Yip
- Subjects
Health (social science) ,History and Philosophy of Science - Published
- 2023
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37. Relationship between online social support and adolescents' mental health: A systematic review and meta-analysis
- Author
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Qijin Cheng and Ziyao ZHOU
- Subjects
Adult ,Social Psychology ,Adolescent ,Loneliness ,Social Support ,Friends ,Self Concept ,Psychiatry and Mental health ,Young Adult ,Mental Health ,Pediatrics, Perinatology and Child Health ,Developmental and Educational Psychology ,Humans ,Female ,Child - Abstract
The potential benefits of supportive interactions on social networking sites on adolescents' mental health are promising; however, no systematic evaluation has been conducted on this topic. This review examined empirical research on the relationship between social support derived from social networking sites and adolescents' mental health both theoretically and empirically.Followed PRISMA guidelines, we conducted a systematic literature search on six English and three Chinese databases in February 2020. Four thousand one hundred and seventy-seven articles were screened first by title, then abstract, and lastly, full articles.Fourteen studies (five English and nine Chinese) were identified, with total sample of 11,616 adolescents (age: 10-19 years; females: 42.7%-56.3%). Meta-analysis showed that the correlation of online social support with self-esteem was moderate and significant (r = .29), but with depression was small and insignificant (r = -.09). Sensitivity analysis indicated that social support from acquaintances on the internet may not be as beneficial as from real-life acquaintances. Despite that there isn't enough research on other specific mental health outcomes to run a quantitative synthesis, individual studies suggest that online social support (OSS) may be associated with increased self-identity and life satisfaction, decreased loneliness and social anxiety, it also counteracts the negative effect of stress and cyberbullying on mental health.OSS might be beneficial for adolescents' mental health, especially self-esteem, although the causal relationship requires longitudinal studies to confirm, and the underlying mechanisms need further investigation.
- Published
- 2022
38. The Opportunities and Challenges of the First Three Years of Open Up, an Online Text-Based Counselling Service for Youth and Young Adults
- Author
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Paul Siu Fai Yip, Wai-Leung Chan, Christian S. Chan, Lihong He, Yucan Xu, Evangeline Chan, Yui Chi Chau, Qijin Cheng, Siu-Hung Cheng, Florence Cheung, James Chow, Shirley Chow, Jerry Fung, Siu-Man Hsu, Yik Wa Law, Billie Lo, Sze-Man Miu, Wai Man Ng, Ken Ngai, Christy Tsang, Cynthia Xiong, and Zhongzhi Xu
- Subjects
Counseling ,Text Messaging ,Adolescent ,Health, Toxicology and Mutagenesis ,online emotional support service ,online text-based counselling ,Public Health, Environmental and Occupational Health ,youth suicide prevention ,Article ,Suicidal Ideation ,Young Adult ,Mental Health ,crisis intervention ,Artificial Intelligence ,Hong Kong ,Humans ,Medicine - Abstract
We present the opportunities and challenges of Open Up, a free, 24/7 online text-based counselling service to support youth in Hong Kong. The number of youths served more than doubled within the first three years since its inception in 2018 in response to increasing youth suicidality and mental health needs. Good practice models are being developed in order to sustain and further scale up the service. We discuss the structure of the operation, usage pattern and its effectiveness, the use of AI to improve users experience, and the role of volunteer in the operation. We also present the challenges in further enhancing the operation, calling for more research, especially on the identification of the optimal number of users that can be concurrently served by a counsellor, the effective approach to respond to a small percentage of repeated users who has taken up a disproportional volume of service, and the way to optimize the use of big data analytics and AI technology to enhance the service. These advancements will benefit not only Open Up but also similar services across the globe.
- Published
- 2021
39. Numerical simulation of graphene/GaAs heterojunction solar cells
- Author
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Meng Yu, Qijin Cheng, Yanqiu Li, and Shuai Li
- Subjects
Electrode material ,Materials science ,Computer simulation ,Renewable Energy, Sustainability and the Environment ,Graphene ,business.industry ,020209 energy ,Photovoltaic system ,Heterojunction ,02 engineering and technology ,021001 nanoscience & nanotechnology ,law.invention ,law ,Electrode ,0202 electrical engineering, electronic engineering, information engineering ,Optoelectronics ,General Materials Science ,Work function ,0210 nano-technology ,business ,Layer (electronics) - Abstract
For a thorough understanding of graphene/GaAs heterojunction solar cells, the effect of the graphene work function, absorption loss, density of interface states, as well as the incorporation of an AlxGa1−xAs ( 0 ≤ x ≤ 1 ) buffer layer on the performance of graphene/GaAs heterojunction solar cells was investigated via AFORS-HET simulation software. It is demonstrated that graphene with a work function of approximately 5 eV favors the efficiency improvement. The absorption loss is also an unnegligible factor for the optimization of the graphene work function. The density of interface states can significantly affect the carrier recombination at the heterojunction interface between graphene and GaAs and the corresponding photovoltaic performance. In addition, the work function of a back electrode should also be taken into account for selecting a back electrode material due to its significant influence on the carrier transportation and collection. Furthermore, when an AlxGa1−xAs (x = 0.2) buffer layer was introduced to this heterojunction interface, an enhanced photovoltaic conversion efficiency of 24.78% can be achieved. Finally, a comparison among simulation and experimental data for the graphene/GaAs heterojunction solar cells is presented. This study indicates the great potential of graphene/GaAs heterojunction for the application in high-efficiency solar cells.
- Published
- 2019
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40. Peer Support and Mental Health of Migrant Domestic Workers: A Scoping Review
- Author
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Ken Hok Man Ho, Chen Yang, Alex Kwun Yat Leung, Daniel Bressington, Wai Tong Chien, Qijin Cheng, and Daphne Sze Ki Cheung
- Subjects
Counseling ,Transients and Migrants ,Mental Health ,Health Personnel ,Health, Toxicology and Mutagenesis ,Public Health, Environmental and Occupational Health ,Humans ,Peer Group - Abstract
The effectiveness of peer support in improving mental health and well-being has been well documented for vulnerable populations. However, how peer support is delivered to migrant domestic workers (MDWs) to support their mental health is still unknown. This scoping review aimed to synthesize evidence on existing peer support services for improving mental health among MDWs. We systematically searched eight electronic databases, as well as grey literature. Two reviewers independently performed title/abstract and full-text screening, and data extraction. Twelve articles were finally included. Two types of peer support were identified from the included studies, i.e., mutual aid and para-professional trained peer support. MDWs mainly seek support from peers through mutual aid for emotional comfort. The study’s findings suggest that the para-professional peer support training program was highly feasible and culturally appropriate for MDWs. However, several barriers were identified to affect the successful implementation of peer support, such as concerns about emotion contagion among peers, worries about disclosure of personal information, and lack of support from health professionals. Culture-specific peer support programs should be developed in the future to overcome these barriers to promote more effective mental health practices.
- Published
- 2022
- Full Text
- View/download PDF
41. Synthesis and Application of MoS 2 in Solar Cells
- Author
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Zikang Ai, Jintao Yuan, Ruiming Huang, Meng Yu, and Qijin Cheng
- Subjects
History ,Polymers and Plastics ,Business and International Management ,Industrial and Manufacturing Engineering - Published
- 2021
- Full Text
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42. Suicide Research in Mainland China, Hong Kong, and Macau Over Three Decades
- Author
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Qijin, Cheng, Xingzhou, Zhang, Carrie, Lui, and Paul S F, Yip
- Subjects
China ,Suicide ,Macau ,Adolescent ,Hong Kong ,Humans - Published
- 2020
43. Optimizing the Electronic Structure of In
- Author
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Yuheng, Gong, Zhenni, Yang, Leonardo, Lari, Irene, Azaceta, Vlado K, Lazarov, Jiaye, Zhang, Xiangyu, Xu, Qijin, Cheng, and Kelvin H L, Zhang
- Abstract
In
- Published
- 2020
44. The Relationship Between Images Posted by New Mothers on WeChat Moments and Postpartum Depression: Cohort Study
- Author
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Wenjie Gong, Lu Liu, Qijin Cheng, Dong Xu, Yan Chen, and Weina Zhang
- Subjects
Postpartum depression ,Adult ,social media ,Population ,Mothers ,050109 social psychology ,Health Informatics ,lcsh:Computer applications to medicine. Medical informatics ,Cohort Studies ,Depression, Postpartum ,WeChat ,medicine ,Childbirth ,Humans ,0501 psychology and cognitive sciences ,education ,Depression (differential diagnoses) ,education.field_of_study ,Original Paper ,lcsh:Public aspects of medicine ,05 social sciences ,Postpartum Period ,lcsh:RA1-1270 ,Odds ratio ,medicine.disease ,postpartum depression ,Edinburgh Postnatal Depression Scale ,lcsh:R858-859.7 ,Female ,Psychology ,WeChat Moments ,Postpartum period ,050104 developmental & child psychology ,Clinical psychology ,Cohort study - Abstract
Background As social media posts reflect users’ emotions, WeChat Moments, the most popular social media platform in China, may offer a glimpse into postpartum depression in the population. Objective This study aimed to investigate the features of the images that mothers posted on WeChat Moments after childbirth and to explore the correlation between these features and the mothers' risk of postpartum depression. Methods We collected the data of 419 mothers after delivery, including their demographics, factors associated with postpartum depression, and images posted on WeChat Moments. Postpartum depression was measured using the Edinburgh Postnatal Depression Scale. Descriptive analyses were performed to assess the following: content of the images, presence of people, the people’s facial expressions, and whether or not memes were posted on WeChat Moments. Logistic regression analyses were used to identify the image features associated with postpartum depression. Results Compared with pictures of other people, we found that pictures of their children comprised the majority (3909/6887, 56.8%) of the pictures posted by the mothers on WeChat Moments. Among the posts showing facial expressions or memes, more positive than negative emotions were expressed. Women who posted selfies during the postpartum period were more likely to have postpartum depression (P=.003; odds ratio 2.27, 95% CI 1.33-3.87). Conclusions The vast majority of mothers posted images conveying positive emotions during the postpartum period, but these images may have masked their depression. New mothers who have posted selfies may be at a higher risk of postpartum depression. Trial Registration International Clinical Trials Registry Platform ChiCTR-ROC-16009255; http://www.chictr.org.cn/showproj.aspx?proj=15699
- Published
- 2020
45. A 24-hour online youth emotional support: Opportunities and challenges
- Author
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Kwai Yau Wong, Cynthia Xiong, Siu Man Hsu, Wai Leung Chan, Billie Lo, Yik-wa Law, Tsz Kong Yeung, Paul S. F. Yip, Ken Ngai, Shirley Chow, and Qijin Cheng
- Subjects
Emotional support ,Health Policy ,lcsh:Public aspects of medicine ,Applied psychology ,Public Health, Environmental and Occupational Health ,Obstetrics and Gynecology ,lcsh:RA1-1270 ,Psychiatry and Mental health ,Infectious Diseases ,Pediatrics, Perinatology and Child Health ,Internal Medicine ,Commentary ,Geriatrics and Gerontology ,Psychology - Published
- 2020
46. Guidelines for Regulating or Rating Mental Health Mobile Applications: A Systematic Review (Preprint)
- Author
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Qijin Cheng and Zirui Chen
- Abstract
BACKGROUND Increasing number of mobile applications (apps) have been released to the market to address mental health needs; however, their quality varies. Mental health professionals have been advocating to set up regulating policies or rating guidelines to facilitate users to make informed choice. OBJECTIVE The study aims to map out the landscape and ecosystem of existing regulating policies and rating guidelines concerning mental health apps, streamline core rating criteria, and identify what knowledge and policy gaps exist. METHODS A systematic review was conducted on both English and Chinese literature. Not only academic publication databases but also popular search engines were searched to identify relevant policies or guidelines. Eligible publications were analyzed to identify key stakeholders in the ecosystem of regulating and rating mental health apps, and common approaches and criteria of the regulating or rating. What limitations exist and what improvement should be achieved in order to make good use of mental health apps were then discussed. RESULTS 56 articles were found to meet our inclusion criteria, covering 31 sets of regulating policies, rating protocols, or specific recommendations. Key stakeholders include app developers, governments, app stores, mental health professionals, and individual users. Only very few countries have released specific regulation policies for mental health apps, whereas app stores were almost absent on this matter. Mental health professionals have been advocating to set up rating guidelines but they did not always engage app developers or ordinary users. Regulation approach is to extend existing regulations on medical devices to mental health apps that self-claim for medical use. Quality rating approach is using either a checklist or a scoring scheme to rate mental health apps’ compliance with some criteria. Specific criteria include privacy and data protection, protecting user safety and minimize risks, evidence-based, usability and front-end accessibility, system interoperability, technical stability, cost, and information timeliness. CONCLUSIONS Only very few jurisdictions and professional organizations in the world have released regulating policies or rating guidelines on mental health apps, which can serve as a basis for other policymakers and professional organizations to adapt. The current regulating policies are rather vague with their applicable scope, whereas the current rating guidelines have relatively high requirement with raters’ capability. Future development needs to address the two major limitations. CLINICALTRIAL Nil.
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- 2020
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47. The Relationship Between Images Posted by New Mothers on WeChat Moments and Postpartum Depression: Cohort Study (Preprint)
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Weina Zhang, Lu Liu, Qijin Cheng, Yan Chen, Dong Xu, and Wenjie Gong
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BACKGROUND As social media posts reflect users’ emotions, WeChat Moments, the most popular social media platform in China, may offer a glimpse into postpartum depression in the population. OBJECTIVE This study aimed to investigate the features of the images that mothers posted on WeChat Moments after childbirth and to explore the correlation between these features and the mothers' risk of postpartum depression. METHODS We collected the data of 419 mothers after delivery, including their demographics, factors associated with postpartum depression, and images posted on WeChat Moments. Postpartum depression was measured using the Edinburgh Postnatal Depression Scale. Descriptive analyses were performed to assess the following: content of the images, presence of people, the people’s facial expressions, and whether or not memes were posted on WeChat Moments. Logistic regression analyses were used to identify the image features associated with postpartum depression. RESULTS Compared with pictures of other people, we found that pictures of their children comprised the majority (3909/6887, 56.8%) of the pictures posted by the mothers on WeChat Moments. Among the posts showing facial expressions or memes, more positive than negative emotions were expressed. Women who posted selfies during the postpartum period were more likely to have postpartum depression (P=.003; odds ratio 2.27, 95% CI 1.33-3.87). CONCLUSIONS The vast majority of mothers posted images conveying positive emotions during the postpartum period, but these images may have masked their depression. New mothers who have posted selfies may be at a higher risk of postpartum depression. CLINICALTRIAL International Clinical Trials Registry Platform ChiCTR-ROC-16009255; http://www.chictr.org.cn/showproj.aspx?proj=15699
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- 2020
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48. Vertically-oriented graphene nanowalls: Growth and application in Li-ion batteries
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Feifei Huang, Jieyang Wu, Junchi Fu, Ling Zhang, Qijin Cheng, Li Shuai, and Qinru Yang
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Materials science ,Argon ,Graphene ,Mechanical Engineering ,chemistry.chemical_element ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Electronic, Optical and Magnetic Materials ,Anode ,Nanomaterials ,Volumetric flow rate ,law.invention ,chemistry ,Chemical engineering ,law ,Materials Chemistry ,Deposition (phase transition) ,Tube furnace ,Electrical and Electronic Engineering ,0210 nano-technology ,Carbon - Abstract
Vertically-oriented graphene nanowalls (VGNWs) have been successfully synthesized under different experimental conditions (such as flow rate of argon, growth temperature, plasma power as well as deposition time) on copper foils in the reactive methane and argon environment using a capacitively coupled plasma-enhanced horizontal tube furnace deposition system. It is shown that the morphology and structure of VGNWs can be effectively tailored by experimental conditions. Furthermore, the growth mechanism of VGNWs produced in the plasma-based approach has been investigated. The synthesized VGNWs are used as anode materials in Li-ion batteries and the batteries show outstanding cycle efficiency (~99%). The specific capacity of coin-type cells can be improved by adjusting the experimental parameters and reaches 400 mAh g−1 in the first charge-discharge cycle. This work is particularly important for the development of an advanced process for the synthesis and application of carbon-based nanomaterials.
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- 2019
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49. Association between suicide reporting in the media and suicide: systematic review and meta-analysis
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Martin Voracek, Marlies Braun, Qijin Cheng, Thomas Niederkrotenthaler, Benedikt Till, Ulrich S. Tran, Mark Sinyor, Florian Arendt, Jane Pirkis, Sebastian Scherr, Steven Stack, Matthew J Spittal, and Paul S. F. Yip
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Funnel plot ,Famous Persons ,Population ,Poison control ,Rate ratio ,Suicide prevention ,03 medical and health sciences ,0302 clinical medicine ,Medicine ,Humans ,030212 general & internal medicine ,Mass Media ,education ,education.field_of_study ,business.industry ,Research ,Interrupted Time Series Analysis ,General Medicine ,Publication bias ,030227 psychiatry ,Suicide ,Suicide methods ,Meta-analysis ,ddc:300 ,business ,Publication Bias ,Demography - Abstract
ObjectiveTo examine the association between reporting on suicides, especially deaths of celebrities by suicide, and subsequent suicides in the general population.DesignSystematic review and meta-analysis.Data sourcesPubMed/Medline, PsychInfo, Scopus, Web of Science, Embase, and Google Scholar, searched up to September 2019.Review methodsStudies were included if they compared at least one time point before and one time point after media reports on suicide; follow-up was two months or less; the outcome was death by suicide; and the media reports were about non-fictional suicides. Data from studies adopting an interrupted time series design, or single or multiple arm before and after comparisons, were reviewed.Results31 studies were identified and analysed, and 20 studies at moderate risk of bias were included in the main analyses. The risk of suicide increased by 13% in the period after the media reported a death of a celebrity by suicide (rate ratio 1.13, 95% confidence interval 1.08 to 1.18; 14 studies; median follow-up 28 days, range 7-60 days). When the suicide method used by the celebrity was reported, there was an associated 30% increase in deaths by the same method (rate ratio 1.30, 95% confidence interval 1.18 to 1.44; 11 studies; median follow-up 28 days, range 14-60 days). For general reporting of suicide, the rate ratio was 1.002 (0.997 to 1.008; five studies; median follow-up 1 day, range 1-8 days) for a one article increase in the number of reports on suicide. Heterogeneity was large and partially explained by celebrity and methodological factors. Enhanced funnel plots suggested some publication bias in the literature.ConclusionsReporting of deaths of celebrities by suicide appears to have made a meaningful impact on total suicides in the general population. The effect was larger for increases by the same method as used by the celebrity. General reporting of suicide did not appear to be associated with suicide although associations for certain types of reporting cannot be excluded. The best available intervention at the population level to deal with the harmful effects of media reports is guidelines for responsible reporting. These guidelines should be more widely implemented and promoted, especially when reporting on deaths of celebrities by suicide.Systematic review registrationPROSPERO CRD42019086559.
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- 2020
50. Numerical Simulation of n‐MoSe 2 /p‐Si Solar Cells by AFORS‐HET
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Yuheng Shen, Meng Yu, Ruiming Huang, and Qijin Cheng
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Statistics and Probability ,Numerical Analysis ,Multidisciplinary ,Modeling and Simulation - Published
- 2022
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