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2.
BMC Psychiatry ; 24(1): 55, 2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38243210

RESUMEN

BACKGROUND: With the advent of the new media era, the understanding of adolescent internet addiction needs to be enriched. It is also necessary to distinguish the related factors of adolescent internet addiction at different levels to clarify the mechanisms of this phenomenon. METHODS: This study used hierarchical linear model analysis to explore the effects of student-level factors and school-level factors on adolescent internet addiction, along with cross-level moderating effects. A total of 1,912 students between the 4th and 8th grades in China participated in the study. Participants completed the Self-Esteem Scale, Parents Phubbing Scale, Classroom Environment Scale, and the Diagnostic Questionnaire of Internet Addiction. RESULTS: Correlational analyses revealed that internet addiction was found to be negatively correlated with both self-esteem and the teacher-student relationship (p < 0.01), while father phubbing, mother phubbing, and learning burden were shown to positively correlate with internet addiction (p < 0.01). Hierarchical linear model analysis suggested that student-level variables, including self-esteem, and mother phubbing, were significant predictors of internet addiction (ß = -0.077, p < 0.001 and ß = 0.028, p < 0.01, respectively). At the school level, learning burden significantly and negatively predicted internet addiction (ß = 0.073, p < 0.05). Furthermore, the relationship between self-esteem and internet addiction was significantly moderated by learning burden (ß = -0.007, p < 0.05). Meanwhile, the teacher-student relationship also had a significant moderating effect on the association between mother phubbing and internet addiction (ß = -0.005, p < 0.01). CONCLUSIONS: This study revealed the relationships between self-esteem, parental phubbing, and classroom environment with adolescent internet addiction, and these findings could provide insights into reducing adolescent internet addiction from the perspective of individuals, families, and schools.


Asunto(s)
Conducta Adictiva , Trastorno de Adicción a Internet , Femenino , Humanos , Adolescente , Modelos Lineales , Padres , Madres , Internet
3.
Environ Res ; 244: 117898, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38092242

RESUMEN

Sorption by soil is the fundamental basis for environment fate of hydrophobic organic contaminants (HOCs), which varies significantly depending on diverse properties of soils. Therefore, a generalized approach to predict HOC sorption by soils is required. In this study, 488 data points were extracted from references and adopted to develop models for estimating the sorption capacities of phenanthrene in soils using six different machine learning (ML) approaches. The extreme gradient boosting (XGBT) model demonstrated the most favorable performance, achieving a coefficient of determination of 0.91 and root-mean-square errors of 0.24 for the testing dataset. The XGBT model's performance was further demonstrated by comparing with experimental data from batch sorption tests conducted on 20 soil samples collected from 17 provinces of China. The differences between the predicted values and the experimental values were statistically equal to zero (p = 0.14). Leveraging the XBGT model together with soil properties from the Harmonized World Soil Database, the distribution of sorption capacities in Chinese soils was successfully depicted on a national scale. This research is expected to contribute to a deeper understanding of the migration of persistent organic pollutants in terrestrial system. Furthermore, the established model holds implications for more precise and scientific soil environmental management.


Asunto(s)
Fenantrenos , Contaminantes del Suelo , Suelo , Adsorción , Contaminantes del Suelo/análisis , Interacciones Hidrofóbicas e Hidrofílicas , Fenantrenos/química
4.
Polymers (Basel) ; 15(24)2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-38139967

RESUMEN

Herein, ZIF-8 inorganic particles with different sized reinforced poly (vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) solid composite polymer electrolytes (PVDF-HFP/10%ZIF-8) were prepared via a facile blade-coating approach, and free-standing quasi solid-state composite electrolytes (PVDF-HFP/10%ZIF-8(0.6)/Plasticizer, abbreviated as PH/10%ZIF-8(0.6)/P), were further obtained through the introduction of plasticizer. Optimized PH/10%ZIF-8(0.6)/P exhibited a high ionic conductivity of 2.8 × 10-4 S cm-1 at 30 °C, and superior Li+ transfer number of 0.89 with an ultrathin thickness (26 µm). Therefore, PH/10%ZIF-8(0.6)/P could effectively inhibit the growth of lithium dendrites, and the assembled Li/LiFePO4 cell delivered good cycling stability with a capacity retention rate of 89.1% after 100 cycles at 0.5 C.

5.
Polymers (Basel) ; 15(12)2023 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-37376245

RESUMEN

Developing an advanced electrode structure is highly important for obtaining lithium sulfur (Li-S) batteries with long life, low cost, and environmental friendliness. Some bottlenecks, such as large volume deformation and environmental pollution caused by the electrode preparation process, are still hindering the practical application of Li-S batteries. In this work, a new water-soluble, green, and environmentally friendly supramolecular binder (HUG) is successfully synthesized by modifying natural biopolymer (guar gum, GG) with HDI-UPy (cyanate containing pyrimidine groups). HUG can effectively resist electrode bulk deformation through a the unique three-dimensional nanonet-structure formed via covalent bonds and multiple hydrogen bonds. In addition, abundant polar groups of HUG have good adsorption properties for polysulfide and can inhibit the shuttle movement of polysulfide ions. Therefore, Li-S cell with HUG exhibits a high reversible capacity of 640 mAh g-1 after 200 cycles at 1C with a Coulombic efficiency of 99%.

6.
Curr Psychol ; : 1-12, 2023 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-37359702

RESUMEN

The present study aimed to investigate the longitudinal and reciprocal relationships among problematic smartphone use (PSU), depressive symptoms (DS), and suicidal ideation (SI) in Chinese university students. Using a cross-lagged design, the Mobile Phone Addiction Inventory Scale, the Center for Epidemiologic Studies Depression Scale, and the Self-Rating Idea of Suicide Scale as research instruments, 194 university students completed a questionnaire four consecutive times. June of Year 1, December of Year 2, June of Year 2, and December of Year 3 of their college study. We refer to these as the Time 1 (T1), Time 2 (T2), Time 3 (T3), and Time 4 (T4) assessments, respectively. The levels of PSU and DS fluctuated significantly over time. DS at T1 was significantly predicted to influence SI at T2 (ß = 0.17, p < .05); DS at T3 was significantly predicted by PSU and by SI at T2 (respectively, ß = 0.30, p < .05; ß = 0.21, p < .05); DS at T2 significantly predicted PSU at T3 (ß = 0.14, p < .05); and DS at T3 significantly predicted SI at T4 (ß = 0.14, p < .05) in the cross-lagged pathway. DS at T3 fully mediated the relationship between PSU at T2 and SI at T4 (indirect effect: ß = 0.133, 95% CI = [0.063, 0.213]). The results suggest that there is a reciprocal relationship between PSU and DS and, furthermore, that DS plays an important mediating role between PSU and SI. Our results suggest the importance of early identification and treatment of SI. Timely reduction of PSU and improvement of DS among university students may help prevent SI.

7.
Int J Biol Macromol ; 239: 124275, 2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-37011751

RESUMEN

Natural polysaccharide-based hydrogels have drawn much concern in the biomedical fields. Among them, alginate, a natural polyanionic polysaccharide, has become one of the research hotspots, because of its abundant source, biodegradability, biocompatibility, solubility, modification flexibility, and other characteristics or physiological functions. Recently, through adopting various physical or chemical crosslinking strategies, selecting suitable crosslinking or modification reagents, precisely controlling the reaction conditions, or introducing organic or inorganic functional materials, a variety of alginate-based hydrogels with excellent performance have been continuously developed, considerably expanding the breadth and depth of their applications. Here, various crosslinking strategies in the preparation of alginate-based hydrogels are comprehensively introduced. The representative application progress of alginate-based hydrogels in drug carrier, wound dressing and tissue engineering is also summarized. Meanwhile, the application prospects, challenges and development trends of alginate-based hydrogels are discussed. It is expected to provide guidance and reference for the further development of alginate-based hydrogels.


Asunto(s)
Alginatos , Hidrogeles , Polisacáridos , Ingeniería de Tejidos , Portadores de Fármacos
8.
Biosens Bioelectron ; 228: 115187, 2023 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-36893719

RESUMEN

In this study, the N-doped carbon dots were continuously synthesized by a facile microfluidic strategy at 90 °C, and their quantum yields reached 19.2%. The characteristics of the obtained carbon dots could be real-time monitored in order to synthesize carbon dots with specific properties. By incorporating the carbon dots into a well-established enzymatic cascade amplification system, an inner filter effect-based fluorescence immunoassay was set up for ultrasensitive detection of cefquinome residues in milk samples. The developed fluorescence immunoassay provided a low detection limit of 0.78 ng/mL, which satisfied the maximum residue limit set by authorities. The fluorescence immunoassay had an 50% inhibition concentration of 0.19 ng/mL against cefquinome and showed a good linear relationship from 0.013 ng/mL to 1.52 ng/mL. While, the average recovery values ranged from 77.8% to 107.8% in spiked milk samples, with relative standard deviations ranging from 6.8% to 10.9%. Compared with conventional methods, the microfluidic chip was more flexible on carbon dots synthesis and the developed fluorescence immunoassay was more sensitive and eco-friendlier for ultra-trace cefquinome residue analysis.


Asunto(s)
Técnicas Biosensibles , Puntos Cuánticos , Animales , Leche/química , Carbono/química , Microfluídica , Temperatura , Técnicas Biosensibles/métodos , Puntos Cuánticos/química , Límite de Detección
9.
Psychol Rep ; 126(5): 2172-2190, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35412349

RESUMEN

Both smartphone addiction and phubbing are emerging behavioral problems. The present study investigates potential risk and protective factors of smartphone addiction and phubbing behavior, including demographic factors, personal factors, and interpersonal factors among Chinese college students. A total of 866 college students (Mage = 21.01, SD = 1.60) completed self-reported questionnaires in classroom settings. Collected data were analyzed by using Pearson's correlation and hierarchical linear regression analyses. The risk factors for smartphone addiction were phubbing behavior, depression, and social anxiety, while the protective factors were self-control and sense of security. In addition, the risk factors for phubbing behavior included female sex and smartphone addiction, while the protective factors included sense of security and interpersonal adaptability. Our findings help to enhance understanding of the general and specific risks and protective factors for smartphone addiction and phubbing behavior, which can benefit intervention development for related behavior prevention and reduction.


Asunto(s)
Conducta Adictiva , Trastorno de Adicción a Internet , Humanos , Femenino , Adulto Joven , Adulto , Factores Protectores , Estudiantes , Miedo , China , Teléfono Inteligente
10.
Biochem Genet ; 61(2): 725-741, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36104590

RESUMEN

Lung cancer is the most commonly diagnosed cancer and the leading reason for tumor-related mortality, while non-small cell lung cancer (NSCLC) is the most usual type of lung cancer. Circular RNAs (circRNAs) have emerged as vital regulators in the development of human cancers, including NSCLC. We aimed to explore the functions of circRNA leukemia inhibitory factor receptor (circLIFR) in NSCLC progression. Real-time quantitative polymerase chain reaction (RT-qPCR) was used to quantify the expression of circLIFR, microRNA-429 (miR-429), and Elav-like family member 2 (CELF2) in NSCLC tissues and cells. Cell proliferation capability of NSCLC cells was determined by Cell Counting Kit-8 (CCK-8) and colony formation assays. The flow cytometry assay was performed to evaluate cell-cycle distribution and apoptosis of NSCLC cells. The abilities of migration and invasion were measured by transwell assay. In addition, the activities of caspase 3 and caspase 9 were measured by the assay kits. The interaction relationship between miR-429 and circLIFR or CELF2 was analyzed by dual-luciferase reporter, RNA immunoprecipitation (RIP), and RNA pull-down assays. The expression levels of related proteins were examined by Western Blot assay. The xenograft experiment was established to explore the role of circLIFR in vivo. CircLIFR, circular, and stable transcript in NSCLC cells, was decreased more than 2 folds in NSCLC tissues and cells than controls (P < 0.0001). Importantly, overexpression of circLIFR impeded cell proliferation, migration, invasion, and inactivated protein kinase B (AKT)/phosphatase and tensin homolog (PTEN)-signaling pathways while enhanced apoptosis and cell-cycle arrest in NSCLC cells, which was overturned by upregulation of miR-429 or silencing of CELF2. Furthermore, the upregulation of circLIFR inhibited NSCLC tumor growth in vivo. Overexpression of circLIFR could suppress NSCLC progress by acting as a sponge of miR-429 to regulate the expression of CELF2 and PTEN/AKT-signaling pathways in NSCLC.


Asunto(s)
Proteínas CELF , Carcinoma de Pulmón de Células no Pequeñas , Subunidad alfa del Receptor del Factor Inhibidor de Leucemia , Neoplasias Pulmonares , MicroARNs , Humanos , Carcinoma de Pulmón de Células no Pequeñas/genética , Proliferación Celular , Neoplasias Pulmonares/genética , MicroARNs/genética , Proteínas del Tejido Nervioso , Proteínas Proto-Oncogénicas c-akt , Subunidad alfa del Receptor del Factor Inhibidor de Leucemia/genética
11.
BMC Psychiatry ; 22(1): 747, 2022 11 30.
Artículo en Inglés | MEDLINE | ID: mdl-36451113

RESUMEN

BACKGROUND: This study aimed to categorize different subgroups of problematic smartphone use in Chinese college students. Differences in gender and psychosocial characteristics of the categorized groups were also examined. METHODS: A total of 1123 participants completed the Mobile Phone Addiction Index Scale, the Center for Epidemiologic Studies Depression Scale, the Perceived Social Support Scale, and the Perceived Stress Scale. Using latent profile analysis, we identified different subgroups of problematic smartphone use in college students. Multivariate logistic regression analysis was implemented to examine the relationship between latent classes and demographic and psychosocial covariates. RESULTS: The four following latent classes were identified: a low-risk group, a moderate-risk with no evasiveness group, a moderate-risk with evasiveness group, and high-risk group that accounted for 11%, 24.1%, 35.5%, and 29.4% of the total sample, respectively. Further analysis revealed that female participants were more likely to be in the moderate-risk with evasiveness and high-risk groups, and individuals with depressed mood were more likely to be in the moderate-risk and high-risk groups. CONCLUSIONS: Classifying college students according to the features of problematic smartphone use is potentially useful for understanding risk factors and developing targeted prevention and intervention programs.


Asunto(s)
Teléfono Inteligente , Estudiantes , Femenino , Humanos , Pueblo Asiatico , Factores de Riesgo , China/epidemiología
12.
ACS Nano ; 16(11): 19271-19280, 2022 11 22.
Artículo en Inglés | MEDLINE | ID: mdl-36227202

RESUMEN

Tactile recognition is among the basic survival skills of human beings, and advances in tactile sensor technology have been adopted in various fields, bringing benefits such as outstanding performance in manipulating objects and general human-robot interactions. However, promoting enhanced perception of the existing tactile sensors is limited by their sensor array arrangement and wire-connected design. Here we present a wireless flexible magnetic tactile sensor (FMTS) consisting of a multidirection magnetized flexible film (perception module) and a contactless Hall sensor (signal receiving module). The flexible magnetic film is composed of NdFeB microparticles and soft silicone elastomer microparticles, and it transfers the unambiguous transduction of external force position and magnitude into magnetic signals. Benefiting from the specific magnetization arrangement and clustering algorithm, only one Hall sensor is needed in FMTS to perceive the magnitude and position of the contact spot simultaneously with super-resolution (2.1 mm average error) on a large area (3600 mm2), and the effective working distance is also greatly extended (∼30 mm), allowing for the full softness and adaptability to diverse conditions. We anticipate that this design will promote the development of soft tactile sensors and their integration into human-robot interaction and humanoid robot perception.


Asunto(s)
Fenómenos Mecánicos , Tacto , Humanos , Tacto/fisiología , Fenómenos Magnéticos
13.
Front Psychol ; 13: 876116, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35664204

RESUMEN

Purpose: The present study examined whether and how attitudes toward the COVID-19 vaccine (i.e., safety, efficacy, and price), mental health statuses (i.e., perceived stress and depression), and interpersonal factors (i.e., online social support, perceived social support) would predict COVID-19 vaccine hesitancy. Patients and methods: The two-wave longitudinal surveys were conducted in December 2019 and 2020 in Chinese medical college students (N = 194). Well- validated measures were used, including the Perceived Stress Scale, the Center for Epidemiologic Studies Depression Scale, the Online Social Support Questionnaire, and the Perceived Social Support Scale. Perceived safety, efficacy, price of COVID-19 vaccine, vaccine hesitancy, and actual intake were also measured. Results: Only 2.1% of participants had been vaccinated against COVID-19 in the early stages of the pandemic; 13.4% intended to get vaccinated in the next 3 months, and 66% intended to have it in the next 12 months upon follow-up. Multiple regression analyses revealed that perceived stress (ßm = -0.15, p < 0.05) and depression (ßm = -0.15, p < 0.05) were risk factors for positive attitudes toward the COVID-19 vaccine; online social support (ORm = 1.41, p < 0.01) and positive attitudes toward the COVID-19 vaccine (ORm = 1.83, p < 0.01) were protective factors of intention to get vaccinated in future. Conclusion: Findings suggest that intervention efforts should be made to reduce negative attitudes toward the COVID-19 vaccine among people with poor mental health and enhance online social support to promote COVID-19 vaccination.

14.
Addict Behav ; 128: 107233, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35030454

RESUMEN

BACKGROUND AND AIMS: The Common-Sense Model asserts that illness representations of a health threat affect coping and behavioral reactions to it. Internet gaming disorder (IGD) is a newly defined mental disorder and leads to various health consequences. Little is known about illness representations of IGD and help-seeking for IGD among young adults who are at particular risk of IGD. OBJECTIVE: This study investigated the roles of illness representations in intention to seek help from professionals and important others (families and friends) for IGD in college students in China. METHODS: A two-wave longitudinal study was conducted with a convenience sample of college students in China (N = 591, 57.9% females, Meanage = 19.10). Descriptive analyses and logistic regression analyses were conducted. RESULTS: Approximately 10% of participants were classified as having probable IGD. However, over 70% endorsed self-diagnosed IGD. Less than 40% perceived resources of help-seeking, and most perceived shame for help-seeking. Less than 40% intended to seek help from professionals, and 26% from family and friends. Significant predictors of intention to seek professional help included probable IGD, perceived resources of help-seeking for IGD, consequence, timeline, and treatment. Significant predictors of intention to seek help from family and friends included probable IGD, self-diagnosed IGD, perceived resources of help-seeking for IGD, shame for help-seeking for IGD, timeline, treatment control, identity, concern, and emotional response. Females were more likely to seek both types of help. DISCUSSION AND CONCLUSIONS: Perceptions of IGD and help-seeking play significant roles in help-seeking intentions. These modifiable factors can be used to guide the development of health promotion and behavioral change programs to promote help-seeking for IGD.


Asunto(s)
Conducta Adictiva , Juegos de Video , Adulto , Femenino , Humanos , Masculino , Adulto Joven , Conducta Adictiva/terapia , Intención , Internet , Trastorno de Adicción a Internet/terapia , Estudios Longitudinales , Estudiantes/psicología , Juegos de Video/psicología
15.
Nat Prod Res ; 36(14): 3695-3700, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33538208

RESUMEN

One new lactone derivative helicascolide F (1), one new pyrrolidine derivative talaromydine (2), along with six known compounds (3-8) were isolated from the fungus Talaromyces assiutensis JTY2. The structure of the new compounds 1 and 2 was determined by 1D and 2D NMR as well as by HRESIMS. The inhibitory activity of all compounds against six phytopathogenic fungi and three cancer cell lines was evaluated.


Asunto(s)
Talaromyces , Espectroscopía de Resonancia Magnética , Estructura Molecular , Talaromyces/química
16.
J Affect Disord ; 299: 45-51, 2022 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-34813870

RESUMEN

BACKGROUND: Sleep quality is an important indicator of quality of life. It is of importance to investigate the risk factors and potential consequences of poor sleep quality, such as perceived stress and suicidal ideation. We therefore investigated the longitudinal and reciprocal relationships among perceived stress, suicidal ideation, and sleep quality. METHODS: A three-wave longitudinal survey was conducted from June 2019 to June 2020 at six-month intervals in undergraduate students (N = 197, 58.9% female) in China. The participants completed self-report questionnaires in classroom settings. RESULTS: While the levels of perceived stress were stable, levels of suicidal ideation and sleep quality fluctuated significantly over time. There were significant reciprocal relationships between perceived stress and suicidal ideation from T1 to T3. In addition, the reciprocal relationships between suicidal ideation and sleep quality from T1 to T2 were also significant. Suicidal ideation at T2 partially mediated the relationship between perceived stress at T1 and sleep quality at T3 (indirect effect: ß=0.06, 95% CI: 0.04 to 0.10, p<0.001), and suicidal ideation at T2 fully mediated the relationship between sleep quality at T1 and perceived stress at T3 (indirect effect: ß=0.48, 95% CI: 0.30, 0.70, p<0.001). LIMITATIONS: The subjects' educational background is single, and the measurement method is self-report measures. CONCLUSIONS: Suicidal ideation may play a significant role in explaining the longitudinal relationships between perceived stress and sleep quality. And suggest the importance of early identification and treatment of suicidal ideation among Chinese undergraduates.


Asunto(s)
Calidad del Sueño , Ideación Suicida , China , Femenino , Humanos , Masculino , Calidad de Vida , Factores de Riesgo , Estrés Psicológico/epidemiología , Estudiantes
17.
JMIR Serious Games ; 9(4): e28117, 2021 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-34851298

RESUMEN

BACKGROUND: The common-sense model of illness suggests that mental representations of health threats may affect one's behavioral reactions to them and health status. Internet gaming disorder is a newly defined mental disorder. Illness representations of internet gaming disorder may affect one's risk of internet gaming disorder. In turn, symptoms of internet gaming disorder may affect one's perceptions of the disorder. OBJECTIVE: This study aimed to investigate the relationships between illness representations and symptoms of internet gaming disorder in college students. METHODS: A 1-year longitudinal study was conducted with a convenience sample of Chinese college students (n=591; 342/591, 57.9% female). RESULTS: Of the participants, 10.1% (60/591) and 9.1% (54/591) were classified as having probable internet gaming disorder at baseline (T1) and follow-up (T2), respectively. The correlations between some dimensions of illness representations regarding internet gaming disorder (ie, consequence, timeline, personal control, treatment control, and concern) at T1 and symptoms of internet gaming disorder at T2 and between symptoms of internet gaming disorder at T1 and the dimensions of illness representations at T2 (ie, consequence, timeline, personal control, and emotional response) were statistically significant. The cross-lagged model fit the data well ((χ2/df=2.28, comparative fit index=.95, root mean square error of approximation=.06) and showed that internet gaming disorder at T1 was positively associated with unfavorable illness representations at T2. CONCLUSIONS: Individuals with more severe symptoms of internet gaming disorder had more pessimistic perceptions about the disorder. Such cognitive perceptions may affect one's emotional and behavioral reactions towards the disorder (eg, greater levels of depression and low self-control intention) and should be modified by educational programs and psychological interventions.

18.
Front Public Health ; 9: 752210, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34926377

RESUMEN

Background and Aims: This three-wave longitudinal study investigated the effects of stressful life events on problematic smartphone use and the mediating roles of mental health problems (i.e., depressive symptoms, poor sleep quality, and suicidal ideation) in Chinese undergraduate students. Methods: A total of 197 undergraduate students completed the three-wave surveys. Their severity of stressful life events, mental health problems, and problematic smartphone use were assessed. Results: Regression analyses revealed that stressful life events at T1 was significantly associated with problematic smartphone use at T3. Mediation analyses showed that mental health problems (i.e., depressive symptoms, poor sleep quality, and suicidal ideation) at T2 fully mediated the association between stressful life events at T1 and problematic smartphone use at T3 (B = 0.042, 0.034, and 0.022, respectively). Conclusions: The present study revealed that stressful life events and mental health problems (i.e., depressive symptoms, poor sleep quality, and suicidal ideation) are predictors of problematic smartphone use in Chinese college students.


Asunto(s)
Teléfono Inteligente , China/epidemiología , Humanos , Estudios Longitudinales , Salud Mental , Estudiantes/psicología
19.
Psychol Res Behav Manag ; 14: 529-539, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33976576

RESUMEN

PURPOSE: Recent research has identified a relationship between perceived stress and problematic smartphone usage. However, little is known about the underlying mediating and moderating mechanisms. The present study aimed to test the relationship between perceived stress and problematic smartphone usage as well as the mediating role of online social support and the moderating role of perceived social support among Chinese undergraduates. PATIENTS AND METHODS: A sample of 1123 college students participated in the study. The Perceived Stress Scale, Mobile Phone Addiction Index Scale, Online Social Support Questionnaire, and Perceived Social Support Scale were used. RESULTS: Perceived stress was significantly and positively associated with problematic smartphone usage, and online social support partially mediated the relationship between perceived stress and problematic smartphone usage. Moderated mediation analysis suggested that perceived social support moderated the association between perceived stress and online social support. This relationship became stronger for college students with lower levels of perceived social support. CONCLUSION: The results of this study can contribute to a better understanding of how perceived stress increases the risk of problematic smartphone usage. The importance of reducing online social support and enhancing perceived social support in preventing undergraduates' problematic smartphone usage is highlighted. The findings should be taken with caution given the convenience sampling and cross-sectional study design.

20.
Nano Lett ; 19(12): 8749-8757, 2019 12 11.
Artículo en Inglés | MEDLINE | ID: mdl-31671944

RESUMEN

Inspired by the natural motors capable of performing multiple tasks in complex living environments, synthetic nanomotors emerge as a potential vehicle for revolutionizing biomedical processes. Yet current motors suffer from decreased and even completely hindered motion in a complex physiological environment, shadowing the future of this booming field. To address this problem, a unimolecular nanomotor based on molecular bottlebrush (MBB) of sub-100 nm size is reported. This motor is constructed precisely via controlled radical polymerization and click chemistry and propelled with biocompatible catalase. Such a molecular nanomotor possesses tadpole-like asymmetry and is able to overcome Brownian motion, and demonstrates strong directional propulsion (linear and coiled cyclic trajectories) in a viscous tumor microenvironment gel model at an ultralow hydrogen peroxide level of 2 mM (0.006%). In addition, the molecular nanomotor exhibits superior stability in serum containing cell medium and good biocompatibility in blood. Such molecular bottlebrush based nanomotors may represent a unique platform for overcoming the tissue penetration barrier.


Asunto(s)
Modelos Biológicos , Nanoestructuras , Neoplasias/metabolismo , Microambiente Tumoral , Animales , Ratones , Neoplasias/patología
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