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1.
Adv Mater ; : e2401738, 2024 May 21.
Article En | MEDLINE | ID: mdl-38771624

Metasurface holograms represent a common category of metasurface devices that utilize in-plane phase gradients to shape wavefronts, forming holographic images through the application of the generalized Snell's law (GSL). While conventional metasurfaces focus solely on phase gradients, metagratings, which incorporate higher-order wave diffraction, further expand the GSL's generality. Recent advances in certain acoustic metagratings have demonstrated an updated GSL extension capable of reversing anomalous transmission and reflection, whose reversal is characterized by the parity of the number of wave propagation trips through the metagrating. However, the current extension of GSL has remained limited to one-dimensional metagratings, unable to access two-dimensional (2D) holographic images in three-dimensional (3D) spaces. Here, we investigate the GSL extension to 2D metagratings for manipulating waves within 3D spaces. Through our analysis, we experimentally demonstrate a series of acoustic metagrating holograms. These holographic images exhibit the unique ability to switch between transmission and reflection types independently. Our study introduces an additional dimension to modern holography design and metasurface wavefront manipulation. This article is protected by copyright. All rights reserved.

2.
Front Psychol ; 15: 1332351, 2024.
Article En | MEDLINE | ID: mdl-38328375

Background: As a major public health problem globally, negative risk-taking behavior of college students may be related to their ostracism experience, but the reason for this association is unclear. Based on the limited resource theory, combined with the integrative model of athletic performance, we tested a moderated mediation model in which ego depletion mediated the association between ostracism and risk-taking, and physical exercise moderated the mediation process to examine the mechanisms underlying the association between ostracism and negative risk-taking behavior. Methods: One thousand three hundred seven students (43% female) from four universities in China were recruited using cluster random sampling. The experience of being ostracized, ego depletion, physical exercise level, and negative risk-taking behavior were measured through an anonymous online questionnaire in "www.sojump.com." Results: After controlling for gender and grade in college, ostracism was positively related to negative risk-taking behavior; ego depletion mediated this relationship; and physical exercise level attenuated these direct and indirect relationships. Conclusion: The results highlight individual risk and protective factors associated with negative risk-taking behavior, and provide new perspectives on ways to prevent and reduce college students' negative risk-taking behavior.

3.
Chin J Traumatol ; 26(6): 351-356, 2023 Nov.
Article En | MEDLINE | ID: mdl-37838578

PURPOSE: As common clinical screening tests cannot effectively predict a difficult airway, and unanticipated difficult laryngoscopy remains a challenge for physicians. We herein used ultrasound to develop some point-of-care predictors for difficult laryngoscopy. METHODS: This prospective observational study included 502 patients who underwent laryngoscopy and a detailed sonographic assessment. Patients under 18 years old, or with maxillofacial deformities or fractures, limited mouth opening, limited neck movement or history of neck surgery were excluded from the study. Laryngoscopic views of all patients were scored and grouping using the modified Cormack-Lehane (CL) scoring system. The measurements acquired comprised tongue width, the longitudinal cross-sectional area of the tongue, tongue volume, the mandible-hyoid bone distance, the hyoid bone-glottis distance, the mandible-hyoid bone-glottis angle, the skin-thyrohyoid membrane distance, the glottis-superior edge of the thyroid cartilage distance (DGTC), the skin-hyoid bone distance, and the epiglottis midway-skin distance. ANOVA and Chi-square were used to compare differences between groups. Logistic regression was used to identify risk factors for difficult laryngoscopy and it was visualized by receiver operating characteristic curves and nomogram. R version 3.6.3 and SPSS version 26.0 were used for statistical analyses. RESULTS: Difficult laryngoscopy was indicated in 49 patients (CL grade Ⅲ - Ⅳ) and easy laryngoscopy in 453 patients (CL grade Ⅰ - Ⅱ). The ultrasound-measured mandible-hyoid bone-glottis angle and DGTC significantly differed between the 2 groups (p < 0.001). Difficult laryngoscopy was predicted by an area under the curve (AUC) of 0.930 with a threshold mandible-hyoid bone-glottis angle of 125.5° and by an AUC of 0.722 with a threshold DGTC of 1.22 cm. The longitudinal cross-sectional area of the tongue, tongue width, tongue volume, the mandible-hyoid distance, and the hyoid-glottis distance did not significantly differ between the groups. CONCLUSION: Difficult laryngoscopy may be anticipated in patients in whom the mandible-hyoid bone-glottis angle is smaller than 125.5° or DGTC is larger than 1.22 cm.


Laryngoscopy , Tongue , Humans , Adolescent , Prospective Studies , Tongue/diagnostic imaging , Respiratory System , Ultrasonography
4.
J Affect Disord ; 340: 862-870, 2023 11 01.
Article En | MEDLINE | ID: mdl-37604242

BACKGROUND: The issue of college student suicide has emerged as a significant global public health concern. To date, there has been a lack of extensive research on the effects of distinct forms of bullying victimization (traditional bullying victimization and cyberbullying victimization) on suicidal ideation, as well as the differences between them. The present study aimed to investigate the relationship between two forms of bullying victimization and suicidal ideation among female college students, while also considering the potential mediating effects of rumination and insomnia. METHODS: A total of 2106 female college students from Southern China participated in this study. The participants had a mean age of 19.83 years (SD = 1.04 years). Participants completed the MINI-C questionnaire, School Bullying Behavior Questionnaire, Cyberbullying Inventory (CBI), Ruminative Responses Scale (RRS), and Insomnia Severity Index (ISI). The mediation models were conducted using Model 4 and Model 6 of the Process macro program in SPSS. RESULTS: The results showed that (1) the mediating effect of rumination in the relationship between different forms of bullying victimization and suicidal ideation was significant; (2) The mediating effect of insomnia in the relationship between traditional bullying victimization and suicidal ideation was not significant; the mediating effect between cyberbullying victimization and suicidal ideation was significant. (3) The chain mediating effect of rumination and insomnia in the relationship between different forms of bullying victimization and suicidal ideation were both significant. CONCLUSION: This study endeavor represents the first attempt to investigate the relationship between two forms of bullying victimization and suicidal ideation.


Bullying , Cyberbullying , Sleep Initiation and Maintenance Disorders , Female , Humans , Young Adult , Adult , Suicidal Ideation , Sleep Initiation and Maintenance Disorders/epidemiology , East Asian People , Students
5.
Front Public Health ; 11: 1091959, 2023.
Article En | MEDLINE | ID: mdl-36969626

Cybervictimization has been shown in many studies to be a risk factor for adolescent non-suicidal self-injurious behavior (NSSI). In this study we tested the roles of depression and school connectedness in this association. The Integrative Model of NSSI, Emotion Regulation and Interpersonal Relationship Model of NSSI, and Integrative Model of Social Media and Suicide provided the conceptual framework for the study. A sample of 1106 adolescents (M age = 13.17; SD = 0.69; 51.78% girls) completed anonymous questionnaires in their classrooms. The results of structural equation modeling showed that the positive association between cybervictimization and adolescent NSSI was mediated by depression. Moreover, this indirect link was stronger for adolescents with low vs. high school connectedness. The results have implications for intervention programs aimed at reducing NSSI among adolescents.


Cyberbullying , Depression , Self-Injurious Behavior , Adolescent , Female , Humans , Male , Depression/epidemiology , Depression/psychology , East Asian People , Schools , Self-Injurious Behavior/epidemiology , Self-Injurious Behavior/psychology , Suicidal Ideation
6.
Mar Drugs ; 21(1)2023 Jan 01.
Article En | MEDLINE | ID: mdl-36662212

It has been reported that dietary n-3 polyunsaturated fatty acids (n-3 PUFAs) exert therapeutic potential for the preservation of functional ß-cell mass. However, the effect of dietary n-3 PUFA deficiency on pancreatic injury and whether the supplementation of n-3 PUFA could prevent the development of pancreatic injury are still not clear. In the present study, an n-3 PUFA deficiency mouse model was established by feeding them with n-3 PUFA deficiency diets for 30 days. Results showed that n-3 PUFA deficiency aggravated streptozotocin (STZ)-induced pancreas injury by reducing the insulin level by 18.21% and the HOMA ß-cell indices by 31.13% and the area of islet by 52.58% compared with the STZ group. Moreover, pre-intervention with DHA and EPA for 15 days could alleviate STZ-induced pancreas damage by increasing the insulin level by 55.26% and 44.33%, the HOMA ß-cell indices by 118.81% and 157.26% and reversed the area of islet by 196.75% and 205.57% compared to the n-3 Def group, and the effects were significant compared to γ-linolenic acid (GLA) and alpha-linolenic acid (ALA) treatment. The possible underlying mechanisms indicated that EPA and DHA significantly reduced the ration of n-6 PUFA to n-3 PUFA and then inhibited oxidative stress, inflammation and islet ß-cell apoptosis levels in pancreas tissue. The results might provide insights into the prevention and alleviation of pancreas injury by dietary intervention with PUFAs and provide a theoretical basis for their application in functional foods.


Fatty Acids, Omega-3 , Insulins , Mice , Animals , Fatty Acids, Omega-3/pharmacology , Fatty Acids, Omega-3/therapeutic use , Streptozocin/toxicity , Fatty Acids, Unsaturated , Fatty Acids , Inflammation/drug therapy , Pancreas , Dietary Supplements , Apoptosis , Oxidative Stress , Docosahexaenoic Acids/pharmacology , Eicosapentaenoic Acid/pharmacology
7.
Front Public Health ; 11: 1308186, 2023.
Article En | MEDLINE | ID: mdl-38298255

Background: Non-suicidal self-injury (NSSI) poses a growing risk to public health worldwide. While numerous studies have identified major life events as key risk factors for NSSI, the mechanisms by which emotional and cognitive problems mediate or moderate this relationship remain unclear. To enhance the understanding of this field, we will draw upon the cascade theory of self-injury and the benefits and barriers model, to examine the relationship between major life events and NSSI, as well as the effect of rumination and body image. Methods: A sample of 2,717 college students (Mage = 19.81 years; SD = 1.09) participated in this study and anonymously completed the questionnaires. The moderated mediation model were conducted using Model 4 and Model 15 of the Process macro program in SPSS. Results: The results showed that rumination mediated the positive relationship between major life events and NSSI. Furthermore, body image was found to moderate both the relationship between major life events and NSSI, as well as the relationship between rumination and NSSI. Conclusion: The current findings suggest that rumination is an important mediator in the relationship between major life events and NSSI among college students. Teachers, parents, and researchers should recognize the important role of body image self-perceptions of college students and actively promote a healthy and accurate body image.


Body Image , Self-Injurious Behavior , Humans , Young Adult , Adult , Emotions , Self Concept , Self-Injurious Behavior/etiology , Self-Injurious Behavior/psychology , Students/psychology
8.
Front Biosci (Landmark Ed) ; 27(11): 315, 2022 11 25.
Article En | MEDLINE | ID: mdl-36472113

BACKGROUND: The theory of free radical oxidative stress (ROS) is one of the leading theories of ageing, and antioxidants play an important role in antiaging. Dendrobium has always been popular as a natural antioxidant. METHODS: This study investigated the effects of various polarity fractions of ethanol extracts from Dendrobium nobile Lindl. (D. nobile) on D-galactose-induced aging mice. D. nobile stems were extracted by ethanol to form the crude extract (EA), which was sequentially extracted by trichloromethane, ethyl acetate, and n-butanol to yield the secondary extracts, named TCM, EAC, and NBA, respectively. EA, TCM, EAC and NBA were intragastrically administered at a dose of 200 mg/kg b.w. to the aging mice induced by D-galactose for 8 weeks. RESULTS: Compared with the aging control group (AC), D. nobile extracts reduced body weight and lipid accumulation and enhanced endurance and immunity by increasing the index of the spleens and thymus. Meanwhile, D. nobile extracts showed antioxidant properties by lowering Malondialdehyde (MDA) levels and increasing the activities of superoxide dismutase (SOD), catalase (CAT), and Glutathione peroxidase (GSH-Px) in the skin, blood, liver, and brain. Furthermore, D. nobile extracts had a good protective effect on the cell structure and function against lesions of the skin, liver, brain, kidney, and ovary of aging mice. In particular, EA and EAC had better antioxidant and antiaging effects, suggesting that the most effective components were flavonoids and polyphenols that existed in EAC. Both EA and EAC downregulated the expression of aging-related genes such as Il1a, Il1b, Il1rn, Ccl3, Ccl4, Fos and Gck in the brain at the transcriptome level. Both EA and EAC reversed the increase in the Firmicutes/Bacteroidota ratio in aging mice, increased the abundance of probiotic bacteria Lactobacillus and Muribaculum, and decreased the abundance of pathogenic bacteria such as Staphylococcus, Corynebacterium and Brevibacterium. CONCLUSIONS: The EA and EAC extracts of D. nobile have better effects on immunity improvement, antioxidation and antiaging by remodelling the intestinal microecosystem and downregulating the expression of age-promoting genes in the brain. D. nobile, especially EA and EAC extracts, could be used as an antiaging drug or functional food.


Antioxidants , Dendrobium , Female , Animals , Mice , Antioxidants/pharmacology , Galactose/pharmacology , Dendrobium/chemistry , Oxidative Stress , Aging , Ethanol
9.
Zhongguo Dang Dai Er Ke Za Zhi ; 24(7): 806-811, 2022 Jul 15.
Article Zh | MEDLINE | ID: mdl-35894197

OBJECTIVES: To investigate the differences in non-suicidal self-injury (NSSI) behaviors between only-child and non-only-child adolescents with mood disorders. METHODS: A three-stage sampling method was used to perform a cross-sectional survey of 529 adolescents, aged 12-18 years, who had mood disorders and NSSI behaviors. These adolescents were sampled from the outpatient service of 20 mental hospitals in 9 provinces of China from August to November 2020. A self-made questionnaire was used to collect general demographic data. The Functional Assessment of Self-Mutilation, Beck Scale for Suicide Ideation, Kessler Psychological Distress Scale, Stress Mindset Measure-General, Multidimensional Scale of Perceived Social Support, Multidimensional Students' Life Satisfaction Scales, and Rosenberg Self-Esteem Scale were used to collect the information on self-injury behaviors and psychological factors in these adolescents. RESULTS: A total of 529 adolescents with mood disorders and NSSI behaviors were surveyed, among whom 375 were only-child adolescents and 154 were non-only-child adolescents. Compared with the non-only-child group, the only-child group had a significantly higher total score of Functional Assessment of Self-Mutilation (P<0.05) .The type and frequency of self-injury in the only-child group were significantly higher than those in the non-only-child group (P<0.05). Psychological analysis showed that compared with the non-only-child group, the only-child group had a significantly lower score of self-esteem (P<0.05) and significantly higher scores of psychological distress and depressive symptoms (P<0.05). The multiple linear regression analysis showed that the score of suicidal ideation was positively correlated with the frequency of NSSI behaviors in both only-child and non-only-child adolescents with mood disorders (P<0.05); in the only-child adolescents, the level of self-esteem was negatively correlated with the frequency of NSSI behaviors (P<0.05), and the score of stress perception was positively correlated with the frequency of NSSI behaviors (P<0.05); in the non-only-child adolescents, the score of anxious emotion was positively correlated with the frequency of NSSI behaviors (P<0.05). CONCLUSIONS: Among the adolescents with mood disorders and NSSI behaviors, the only-child adolescents tend to have a higher frequency of self-injury and poorer mental health, and therefore, the only-child adolescents with mood disorders and NSSI behaviors need more attention.


Self Mutilation , Self-Injurious Behavior , Adolescent , Cross-Sectional Studies , Humans , Mood Disorders , Risk Factors , Self-Injurious Behavior/psychology , Suicide, Attempted/psychology
10.
Front Psychiatry ; 13: 856627, 2022.
Article En | MEDLINE | ID: mdl-35573361

Background: The government's COVID-19 pandemic response lockdown strategy had a negative psychological and physical impact on individuals, which necessitated special care to pregnant women's mental health. There has been no large-scale research on the underlying relationship between perceived stress and insomnia symptoms in pregnant Chinese women up to this point. During the COVID-19 pandemic, we wanted to see if there was an association between perceived stress and insomnia symptoms, as well as the moderating impact of resilience for Chinese pregnant women. Methods: This cross-sectional study examined 2115 pregnant women from central and western China using multi-stage sampling methodologies. A systematic questionnaire was used to collect information on sleep quality, perceived stress, and resilience using the Insomnia Severity Index, Perceptual Stress Scale, and Connor and Davidson Resilience Scale. To assess the moderating influence of resilience, hierarchical regressions were used. Results: During the COVID-19 pandemic, 18.53% of respondents (N = 2115) reported experiencing sleeplessness. In pregnant women, perceived stress was positively linked with insomnia symptoms (p < 0.001). Furthermore, resilience significantly attenuated the influence of perceived stress on insomnia symptoms in Chinese expectant mother (ßinteraction = -0.0126, p < 0.001). Conclusion: Pregnant women with strong resilience were less influenced by perceived stress than those with poor resilience. The findings of this study might give empirical proof that health care professionals should identify the relevance of reducing perceived stress in pregnant women with poor resilience and provide better treatment and support when necessary.

11.
Article En | MEDLINE | ID: mdl-35329291

Adolescent internet gaming addiction (IGA) has become a serve public health problem, particularly in China. Despite the fact that the school climate has a significant impact on teenage IGA, little research has looked into the underlying mediating processes. This cross-sectional study looked at the impact of adolescents' perceptions of their school climate (including teacher-student support, student-student support, and opportunities for autonomy) on IGA in a sample of 1053 Chinese adolescents (Meanage = 13.52 years; 52.4% females) using convenient sampling methodology, as well as whether deviant peer affiliation mediated this association. Adolescents' school climate, IGA, and deviant peer affiliation were examined using the School Climate Questionnaire, Internet Gaming Addiction Scale, and two validated tools in this study. The results showed that teacher-student support and student-student support were both negatively associated with IGA, and that these correlations were mediated by deviant peer affiliation. The implications of these findings are discussed.


Adolescent Behavior , Adolescent , Cross-Sectional Studies , Female , Humans , Immunoglobulin A , Internet , Internet Addiction Disorder , Male , Peer Group , Schools
12.
Luminescence ; 36(6): 1452-1458, 2021 Sep.
Article En | MEDLINE | ID: mdl-34000083

A series of ZnWO4 :Eu3+ ,Tb3+ phosphors was prepared using a co-precipitation method at room temperature. The structures and luminescence properties of the materials were characterized using X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, and UV-vis light, differential thermal analysis-thermogravimetric analysis, fluorescence spectra and the calculated Commission Internationale de l'Éclairage (CIE) coordinates. The results showed that the material had a monoclinic structure and the P2/c group was determined using XRD. FTIR spectroscopy confirmed the existence of W-O, Zn-O bonds, and Zn-O-W groups in WO6 and ZnO6 octahedra. In the excitation spectrum, there was an overlap of the broad band charge transfer bands belonging to O2- →W6+ and O2- →Eu3+ or O2- →Tb3+ transitions in the range 200-325 nm, and excitation bands between 350 and 500 nm belonged to the characteristic absorption bands for Eu3+ and Tb3+ . Therefore, the phosphor can be used as a single component tunable phosphor in light-emitting diodes.


Europium , Luminescence , Ultraviolet Rays , X-Ray Diffraction
13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(6): 1645-8, 2014 Jun.
Article Zh | MEDLINE | ID: mdl-25358180

The objectives in the present paper were to study the relationship between the polysaccharide content and the spectrum, aimed at finding a non destructive testing method for the measurement of polysaccharide content Materials in this study were from tissue culture seedlings under different treatments and domesticated plants in different growth stages. In the study, 36 samples were used to build estimation models and another 11 as test samples to examine the models. The relationship between the spectrum and polysaccharide content was investigated by partial least squares regression (PLSR) and factor analysis. The results show that (1) there was stronger correlation between derivative reflectance and polysaccharide content, and the sensitive wavebands mainly concentrated in the visible region. (2) The PLSR model has a high precision, while its prediction accuracy is lower. The models of factor analysis have higher prediction accuracy, the RPD of the model based on spectral reflectance is 2.269 and that of derivative reflectance is 2.305.


Dendrobium/chemistry , Polysaccharides/analysis , Spectrum Analysis , Least-Squares Analysis , Models, Theoretical
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