Binding by the Polycomb complex component BMI1 and H2A monoubiquitination shape local and long-range interactions in the Arabidopsis genome.

Three-dimensional (3D) chromatin organization is highly dynamic during development and seems to play a crucial role in regulating gene expression. Self-interacting domains, commonly called topologically associating domains (TADs) or compartment domains (CDs), have been proposed as the basic structural units of chromatin organization. Surprisingly, although these units have been found in several plant species, they escaped detection in Arabidopsis (Arabidopsis thaliana). Here, we show that the Arabidopsis genome is partitioned into contiguous CDs with different epigenetic features, which are required to maintain appropriate intra-CD and long-range interactions. Consistent with this notion, the histone-modifying Polycomb group machinery is involved in 3D chromatin organization. Yet, while it is clear that Polycomb repressive complex 2 (PRC2)-mediated trimethylation of histone H3 on lysine 27 (H3K27me3) helps establish local and long-range chromatin interactions in plants, the implications of PRC1-mediated histone H2A monoubiquitination on lysine 121 (H2AK121ub) are unclear. We found that PRC1, together with PRC2, maintains intra-CD interactions, but it also hinders the formation of H3K4me3-enriched local chromatin loops when acting independently of PRC2. Moreover, the loss of PRC1 or PRC2 activity differentially affects long-range chromatin interactions, and these 3D changes differentially affect gene expression. Our results suggest that H2AK121ub helps prevent the formation of transposable element/H3K27me1-rich long loops and serves as a docking point for H3K27me3 incorporation.

Chromatin remodeling complexes regulate genome architecture in Arabidopsis.

In eukaryotes, three-dimensional (3D) chromatin architecture maintains genome stability and is important in regulating gene transcription. However, little is known about the mechanisms by which diverse ATP-dependent chromatin remodeling complexes regulate the 3D chromatin structure in plants. We examined the 3D chromatin structure within the ATPase subunit of the SWI/SNF, ISWI, INO80, and CHD remodeling complexes in wild-type (WT) and mutant Arabidopsis thaliana plants by combining high-throughput sequencing with in situ Hi-C, the enrichment of histone marks, nucleosome density, and gene expression. We found that compartment regions switched and compartmental strength was significantly weakened in all four enzyme mutants. Chromatin remodeling complexes differentially regulated the nucleosome distribution pattern and density within the switching compartments. Alterations of nucleosome distribution pattern and density were associated with a reduction in H3K27me3 levels in the chromatin remodeling enzyme mutants and led to compartment switching. Our data show that chromatin remodeling complexes regulate the linear nucleosome distribution pattern and density to promote H3K27me3 deposition, which in turn regulates 3D chromatin structure.

Relationships between Dark Triad and negative emotions during COVID-19 lockdown: The chain mediating roles of negative coping and state boredom.

Personality is distal vulnerability of negative emotions and vital to mental health. Dark Triad was significantly correlated with negative emotions, whereas the mechanisms beneath the relationships were less clear. Based on life history strategy theory (LHS) and cognitive vulnerability-transactional stress model, the study explored the relationships between Dark Triad and negative emotions and investigated the roles of negative coping style and state boredom in the relationships aforementioned during the strict period of COVID-19 lockdown in China. 464 participants (M age = 36.78 years; SD = 10.53) finished a package of measurements online including Depression Anxiety and Stress Scale (DASS-21), Short Dark Triad (SD3), Multidimensional State Boredom Scale (MSBS), and Simplified Coping Style Questionnaire (SCSQ). The results showed there were positive relationships between Dark Triad and depression, anxiety and stress. Moreover, the relationships between Dark Triad and negative emotions were sequentially mediated by negative coping style and state boredom. The present study offered fascinating perspectives in the relationships between Dark Triad and negative emotions, and revealed how Dark Triad affected depression, anxiety and stress during the initial phase of COVID-19 pandemic and strict lockdown among Chinese population. The present results may provide important implications for the prevention and intervention of depression, anxiety and stress during COVID-19 pandemic and lockdown. Specifically, the intervention strategies that focus on reducing Dark Triad, negative coping and boredom may help offset occurrence of negative emotional states.

Association between Chronotype and Sleep Quality among Chinese College Students: The Role of Bedtime Procrastination and Sleep Hygiene Awareness.

Chronotype and sleep quality have been shown to play significant roles in influencing people's physical and mental health. The current study focuses on examining the relationship between chronotype and sleep quality among Chinese college students and exploring the mediating role of bedtime procrastination and the moderating role of sleep hygiene awareness. A sample of 2822 college students (female = 71.4%) aged between 17 and 29 years (M = 19.77, SD = 1.41) were included and completed the measures of the Pittsburgh Sleep Quality Index (PSQI), Morningness-Eveningness Questionnaire (MEQ), Bedtime Procrastination Scale (BPS) and Sleep Hygiene Awareness Scale (SHAS). The results showed that evening-type students reported the lowest sleep quality and highest levels of bedtime procrastination. In contrast, the highest sleep quality and lowest levels of bedtime procrastination were shown by morning-type, exhibiting the neither-type students' intermediate chronotype. Bedtime procrastination partially mediated the relationship between chronotype and sleep quality. Furthermore, sleep hygiene awareness moderated the direct effect of chronotype on sleep quality and the effect of chronotype in the path from chronotype to bedtime procrastination. Specifically, higher levels of sleep hygiene awareness could buffer the adverse effect of chronotype on self-reported sleep quality but bolstered the negative effect of chronotype on bedtime procrastination. Our results suggest that individuals with an evening preference are inclined to postpone their bedtime and further experience poorer sleep quality at night. Sleep hygiene awareness may serve as a protective factor for poor nocturnal sleep. Overall, the findings highlight the importance of reducing bedtime procrastination and improving sleep hygiene awareness in the interventions designed to help college students to own a better sleep quality, especially for those with evening chronotypes.

Machiavellianism and learning-related subjective well-being among Chinese senior high school students: A moderated mediation model.

Based on the life history theory and broadening construction theory, the study aimed to investigate the influence of Machiavellianism on the learning-related subjective well-being and the underlying mechanism, 582 Chinese senior high school students (16.8 ± 0.9 years old) including 289 girls (48.3%) and 310 boys were recruited to participate in this study, and they anonymously filled out questionnaires regarding Machiavellianism, learning-related subjective well-being, gratitude, and subjective family economic level. The results showed that: (1) a higher level of Machiavellianism was associated with a lower level of learning-related subjective well-being; (2) gratitude partially mediated the relationship between Machiavellianism and learning-related subjective well-being; (3) subjective family economic level moderated the links between Machiavellianism and learning-related subjective well-being, and between gratitude and learning-related subjective well-being. This study explained how and when Machiavellianism affected Chinese senior high school students' learning-related subjective well-being and provided a deeper understanding of the relationship between Machiavellianism and learning-related subjective well-being.

Sex Differences in Traditional School Bullying Perpetration and Victimization among Adolescents: A Chain-Mediating Effect.

The study explored sex differences in traditional school bullying perpetration and victimization among Chinese adolescents and the effects of Machiavellianism and school climate. Data were collected from 727 adolescents (M = 16.8 years, SD = 0.9) who completed the Olweus Bully/Victim Questionnaire, Kiddie Machiavellian Scale, and School Climate Perception Questionnaire. Results showed: (1) boys were more likely to bully others and be bullied; (2) both Machiavellianism and school climate partially mediated sex differences in school bullying perpetration and victimization; (3) the chain-mediating effect of Machiavellianism and school climate on sex differences in bullying perpetration and victimization was significant. These results provide insight into the sex differences in Chinese traditional school bullying perpetration and victimization. The implications are interpreted and discussed.

Negative emotions and quality of life among adolescents: A moderated mediation model.

BACKGROUND/OBJECTIVE: Depression, anxiety and stress are known as negative emotions. Previous studies have shown that negative emotions were associated with quality of life. There are a lot of researches on quality of life. However, previous studies mainly focused on health-related quality of life among patients. This study aims to examine the relationship between negative emotions and quality of life as well as the underlying psychological mechanism among community-based samples. METHOD: We surveyed 6,401 adolescents (age: 9-15 years old). Participants were assessed using the Depression Anxiety Stress Scale, Resilience Scale for Chinese Adolescent, Perceived Social Support Scale and the Pediatric Quality of Life Inventory 4.0 Generic Scale for Negative Emotions, Resilience, Social Support and Quality of Life. RESULTS: Results revealed that negative emotions were negatively associated with quality of life, and resilience mediated the relationship between negative emotions and quality of life. Social support moderated all the paths among negative emotions, resilience and quality of life. CONCLUSIONS: Adolescents' quality of life was indirectly affected by negative emotions via resilience, and less affected by negative emotions and more affected by resilience with the improvement of social support. The theoretical and practical implications of these results are discussed.

ANTECECENTES/OBJETIVO: Estrés, ansiedad y depresión son emociones negativas. Estudios previos mostraron que las emociones negativas se asocian con la calidad de vida. Existen numerosas investigaciones centradas en la calidad de vida, sin embargo, los estudios se centran en la calidad de vida de pacientes en relación con su salud. En este estudio se examina la relación entre emociones negativas y calidad de vida, y los mecanismos psicológicos subyacentes. MÉTODO: Encuestamos a 6.401 adolescentes (9-15 años). Los participantes fueron evaluados con la Depression Anxiety Stress Scale, la Resilience Scale for Chinese Adolescent, la Perceived Social Support Scale y el Pediatric Quality of Life Inventory 4.0 Generic Scale for Negative Emotions, Resilience, Social Support and Quality of Life. RESULTADOS: Las emociones negativas fueron negativamente asociadas con la calidad de vida, y la resiliencia medió la relación entre emociones negativas y calidad de vida. El apoyo social moderó todas las vías entre emociones negativas, resiliencia y calidad de vida. CONCLUSIONES: La calidad de vida de los adolescentes fue indirectamente afectada por las emociones negativas mediante la resiliencia, menos afectada por emociones negativas y más afectada por la resiliencia con la mejora en el apoyo social. Se discuten las implicaciones teóricas y prácticas de estos resultados.

Effects of Afternoon Nap Deprivation on Adult Habitual Nappers' Inhibition Functions.

Multiple studies have established the effects of afternoon naps on cognition. However, relatively few studies have investigated the domain of executive functions. Moreover, the effects of napping on inhibition are far from conclusive. The present study employed adult habitual nappers to investigate the effects of afternoon nap deprivation on response-based inhibition assessed by a Go/No-go task and stimulus-based inhibition assessed by a Flanker task and on alertness assessed by a psychomotor vigilance test (PVT) and the Karolinska Sleepiness Scale (KSS). The results showed that afternoon nap deprivation significantly decreased participants' accuracy and reaction speed for the Go/No-go task but not for the Flanker task. In addition, participants' alertness was significantly impaired after nap deprivation in terms of increased subjective sleepiness and worse PVT performance. Task-specific effects of napping on inhibition were demonstrated. The implications of the results are discussed.

The Acute Effects of Intermittent Light Exposure in the Evening on Alertness and Subsequent Sleep Architecture.

Exposure to bright light is typically intermittent in our daily life. However, the acute effects of intermittent light on alertness and sleep have seldom been explored. To investigate this issue, we employed within-subject design and compared the effects of three light conditions: intermittent bright light (30-min pulse of blue-enriched bright light (~1000 lux, ~6000 K) alternating with 30-min dim normal light (~5 lux, ~3600 K) three times); continuous bright light; and continuous dim light on subjective and objective alertness and subsequent sleep structure. Each light exposure was conducted during the three hours before bedtime. Fifteen healthy volunteers (20 ± 3.4 years; seven males) were scheduled to stay in the sleep laboratory for four separated nights (one for adaptation and the others for the light exposures) with a period of at least one week between nights. The results showed that when compared with dim light, both intermittent light and continuous bright light significantly increased subjective alertness and decreased sleep efficiency (SE) and total sleep time (TST). Intermittent light significantly increased objective alertness than dim light did during the second half of the light-exposure period. Our results suggested that intermittent light was as effective as continuous bright light in their acute effects in enhancing subjective and objective alertness and in negatively impacting subsequent sleep.

Negative emotions and quality of life among adolescents: A moderated mediation model / Emociones negativas y calidad de vida en adolescentes: un modelo de mediación

BACKGROUND/OBJECTIVE: Depression, anxiety and stress are known as negative emotions. Previous studies have shown that negative emotions were associated with quality of life. There are a lot of researches on quality of life. However, previous studies mainly focused on health-related quality of life among patients. This study aims to examine the relationship between negative emotions and quality of life as well as the underlying psychological mechanism among community-based samples. METHOD: We surveyed 6,401 adolescents (age: 9-15 years old). Participants were assessed using the Depression Anxiety Stress Scale, Resilience Scale for Chinese Adolescent, Perceived Social Support Scale and the Pediatric Quality of Life Inventory 4.0 Generic Scale for Negative Emotions, Resilience, Social Support and Quality of Life. RESULTS: Results revealed that negative emotions were negatively associated with quality of life, and resilience mediated the relationship between negative emotions and quality of life. Social support moderated all the paths among negative emotions, resilience and quality of life. CONCLUSIONS: Adolescents' quality of life was indirectly affected by negative emotions via resilience, and less affected by negative emotions and more affected by resilience with the improvement of social support. The theoretical and practical implications of these results are discussed

ANTECECENTES/OBJETIVO: Estrés, ansiedad y depresión son emociones negativas. Estudios previos mostraron que las emociones negativas se asocian con la calidad de vida. Existen numerosas investigaciones centradas en la calidad de vida, sin embargo, los estudios se centran en la calidad de vida de pacientes en relación con su salud. En este estudio se examina la relación entre emociones negativas y calidad de vida, y los mecanismos psicológicos subyacentes. MÉTODO: Encuestamos a 6.401 adolescentes (9-15 años). Los participantes fueron evaluados con la Depression Anxiety Stress Scale, la Resilience Scale for Chinese Adolescent, la Perceived Social Support Scale y el Pediatric Quality of Life Inventory 4.0 Generic Scale for Negative Emotions, Resilience, Social Support and Quality of Life. RESULTADOS: Las emociones negativas fueron negativamente asociadas con la calidad de vida, y la resiliencia medió la relación entre emociones negativas y calidad de vida. El apoyo social moderó todas las vías entre emociones negativas, resiliencia y calidad de vida. CONCLUSIONES: La calidad de vida de los adolescentes fue indirectamente afectada por las emociones negativas mediante la resiliencia, menos afectada por emociones negativas y más afectada por la resiliencia con la mejora en el apoyo social. Se discuten las implicaciones teóricas y prácticas de estos resultados

Health behaviors and psychosocial determinants among primary and middle school students in Henan province / 中国学校卫生

Objective@#To investigate the current status and psychosocial determinants of health behavior among primary and middle school students in Henan province,and to provide a reference for the direction and priority of the health education in primary and middle schools.@*Methods@#Through cluster sampling method, 3 603 primary school students age 9 to 15 and 2 791 secondary school students in Henan Province were investigated with Chinese version of the Adolescent Lifestyle Questionnaire(C-ALQ), General Self-efficacy Scale(GSES), Perceived Social Support Scale(PSSS), Resilience Scale for Chinese Adolescents(RSCA), Self-Esteem Scale(SES) during January to June in 2016.@*Results@#The total score of health behavior among primary and middle school students was (80.30±16.36).There were significant differences in health behaviors among students with different gender(P<0.05), age(P<0.01), family income(P<0.01), body mass index(P<0.01), father’s education level (P<0.01) and mother’s education level(P<0.01). Health behaviors were significantly correlated with self-efficacy(r=0.26-0.42, P<0.01), social support(r=0.23-0.39, P<0.01), mental resilience(r=0.26-0.37, P<0.01), and self-esteem(r=-0.28--0.18, P<0.01). Gender, age, family monthly income, BMI, parents’ education level, self-efficacy, psychological resilience, social support and self-esteem was psychosocial determinants of healthy behaviors(P<0.05).@*Conclusion@#The engagement in health behaviors among primary and middle school students in Henan province is acceptable. Demographic and psychosocial determinants of health behaviors among primary and middle school students should be considered in health education curriculum planning.