Method to quickly estimate T1 value by suppressing spin exchange relaxation and magnetic field gradient relaxation in atomic sensors.

The accuracy of atomic sensor is determined by the transverse nuclear spin relaxation time (T2). As the longitudinal nuclear spin relaxation time (T1) is the upper limit of T2, it becomes an important metric for evaluating the merits of alkali vapor cells. However, the conventional method for measuring T1 of pulse delay takes dozens of minutes, which will increase the effect of random errors during the testing process. In order to solve this problem, a method to quickly estimate the value of T1 is proposed by suppressing the influence of spin exchange relaxation and magnetic field gradient relaxation terms on T2. Experimental results indicate that the accuracy is maintained at above 95%, and the testing time is reduced to less than 5%.

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.

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.

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.

Cell-based fluorescent microsphere incorporated with carbon dots as a sensitive immunosensor for the rapid detection of Escherichia coli O157 in milk.

The rapid and early detection of foodborne pathogens in contaminated food is important for ensuring food safety and quality. In this study, a highly sensitive fluorescent immunosensor was developed to detect Escherichia coli O157:H7 in milk, by using microspheres labeled with carbon dots (CDs). The CDs-microspheres were prepared with Staphylococcus aureus cells as the carrier to incorporate CDs particles. Characterization of the microsphere revealed strong intensity, good stability and high uniformity in fluorescence. With Staphylococcal Protein A (SPA) on the surface of S. aureus cells, the microsphere could be easily coupled with various antibodies (e.g., immunoglobulin G). In combination with the immunomagnetic beads technique, a CDs-microsphere immunosensor was established for the specific detection of E. coli O157:H7 in milk. The limit of detection for E. coli O157:H7 is 2.4 × 102 colony-forming unit (CFU)/mL, comparable to that of real-time PCR methods. Milk samples spiked with E. coli O157:H7 at concentrations from 2.4 × 102 to 2.4 × 107 CFU/mL could be detected within 30 min. The coefficients of variation of the intra-assay tests were less than 10%, indicating a good repeatability. Moreover, the method was able to detect trace amounts of E. coli O157:H7 (<10 CFU) in real milk samples, with a 100% (10/10) accuracy after bacterial enrichment. This CDs-microsphere immunosensor shows considerable potential as a rapid and sensitive tool to detect pathogens in milk and other foods.