Who is the hardest to wake up from sleep? An investigation of self-reported sleep inertia using a latent profile analysis.

Few studies have assessed the overall nature and profiles of subjective sleep inertia (SI) within the general population. This study was designed to identify subjective SI profiles and examine the associations between profiles of subjective SI with sociodemographic and sleep-related characteristics. A total of 11 colleges and universities were surveyed from May 30 to June 17, 2021, by convenience sampling. A total of 1,240 participants provided usable data regarding sociodemographic information, Sleep Inertia Questionnaire, and sleep-related characteristics via an online platform. Latent profile analysis was utilised to identify profiles of SI. Multinomial logistic regression was further performed to examine the predisposing factors of profiles of SI. Four profiles of SI were identified: (1) "Low SI", 20%; (2) "Mild SI", 31%; (3) "Moderate SI", 33%; and (4) "Severe SI", 16%. Compared to a Low SI profile, younger, individuals with an evening chronotype, and individuals who had <6 h sleep/night, experienced poor sleep quality, and moderate-to-severe sleep disturbance were at increased risk of experiencing severe SI. Individuals with more languid types tended to show more severe SI, while individuals reporting greater flexibility experienced less SI. This study is the first effort to examine the profiles of subjective SI using latent profile analysis and identified four profiles of SI in the general population. This effort may contribute to a greater understanding of SI, including the development of a screening tool and interventions to reduce SI.

Resilience buffers the association between sleep disturbance and psychotic-like experiences in adolescents.

BACKGROUND: Sleep disturbance may cause psychotic-like experiences (PLEs). The present study aimed to exam their rate of co-occurrence and investigate whether resilience buffers the association. METHODS: A total of 50,625 junior high school students were assessed using the self-compiled socio-demographics and sleep questionnaires, 8-item Positive Subscale of the Community Assessment of Psychic Experiences, 10-item Connor-Davidson Resilience Scale, Patient Health Questionnaire and Generalized Anxiety Disorder Questionnaire. RESULTS: In this sample, 15.8% participants had frequent PLEs in the past month, where 40.1% exhibited comorbid sleep disturbance. Sleep disturbance positively associated with the onset of frequent PLEs, after adjusting for socio-demographics, depression and anxiety. Moderation analysis showed resilience buffers the association between sleep disturbance and PLEs, with a higher level of resilience, the positive effect of sleep disturbance on PLEs would be diminished to a greater extent. CONCLUSIONS: These findings suggested that early attention should be drawn to adolescents with sleep disturbance. Intervention strategies should be enhancing resilience, increasing sleep duration and improving sleep quality.

Electrophysiological mechanisms underlying hypoxia-induced deficits in visual spatial and non-spatial discrimination.

Impaired visual cognition in residents of hypoxic environment has been widely reported; however, the underlying electrophysiological mechanisms remain unclear. In this study, 23 college students underwent three sessions of a Clock task test before a 30-day high-altitude exposure (Test 1) and 1 week (Test 2) and 3 months (Test 3) after they returned to lowlands. The Clock task consists of a visual spatial angle and a visual non-spatial color discrimination subtask. Simultaneously, electroencephalography (EEG) was recorded during the Clock task. The behavioral results showed that, compared with Test 1, accuracy in Test 2 was significantly decreased in both the Angle and Color tasks, and reaction time (RT) was significantly increased in the Angle task. The event-related potentials results showed that, during both tasks amplitudes of the occipital N1 and P3 components during both tasks were significantly decreased in Test 2, compared with Test 1. Moreover, N1 amplitude was negatively correlated with RT and positively correlated with accuracy. Further time-frequency EEG analysis showed that theta power at occipital sites was significantly decreased in both tasks in Test 2, compared with Test 1, and was negatively correlated with RT in the Angle task. In Test 3, both the behavioral performance and EEG activity recovered to the baseline level in Test 1. These findings suggested that hypoxia impairs both visual spatial and visual non-spatial discriminations, and these impairments can recover after subjects return to lowlands. Inhibition of brain electrophysiological activity in the visual cortex may explain the deficits in visual cognition.

Sleep disturbance predicts suicidal ideation during COVID-19 pandemic: A two-wave longitudinal survey.

BACKGROUND: This study aimed to examine the cross-sectional and longitudinal associations between sleep disturbance and suicidal ideation (SI) in a large cohort of adolescents experiencing the Coronavirus disease 2019 (COVID-19) crisis in China. METHODS: One two-wave longitudinal web-based survey of sleep, SI, and depression was conducted among 67,905 college students (mean age = 20.23 years, SD = 1.63 years; 31.3% male) during the COVID-19 outbreak (Time1, T1: Feb 3rd to 10th, 2020) and initial remission period (Time2, T2: March 24th to April 3rd, 2020). RESULTS: At T1 and T2, 8.5% and 9.7% of students reported sleep disturbance, 7.6% and 10.0% reported SI, respectively. The prevalence rates of SI at T1 and T2 increased significantly with sleep disturbance and short sleep duration. After adjusting for demographics, pandemic related factors, and depression at T1, sleep disturbance and short sleep duration at T1 were significantly associated with increased risk for SI at T2. Furthermore, sleep disturbance and short sleep duration predicted the new onset and persistence of SI. CONCLUSION: These findings suggested that sleep disturbance predicts the development and persistence of SI. Early assessment and treatment of sleep disturbance may be an important strategy for prevention and intervention of SI in individuals after exposure to the special public health emergency of COVID-19.

Is returning to school during the COVID-19 pandemic stressful? A study on immediate mental health status of Chinese college students.

BACKGROUND: As the COVID-19 pandemic has posed substantial impacts on individual's daily routine and psychological state. For the first time at great scale, Chinese college students had their educational activities moved online in spring 2020. Due to this unexpected isolation and unconventional learning method, their mental health following returning to school is worth investigating. METHODS: Between June 1 and June 15, 2020, a total of 8,921 returning college students' mental health status were assessed using instruments designed for psychiatric disorders, namely the 9-Item Patient Heath Questionnaire (PHQ-9), 7-Item Generalized Anxiety Disorder Scale (GAD-7), 6-Item Impact of Event Scale (IES-6), Youth Self Rating Insomnia Scale (YSIS), and self-developed questionnaire. RESULTS: Our results showed that 8.7%, 4.2%, 10.5%, and 6.1% of the participants experienced depression, anxiety, acute stress, and insomnia, respectively, with a total of 19.8% reporting having at least one psychiatric symptom following their return to school. Sophomore and Senior year, and presence of previous psychiatric conditions contribute to the increased occurrence of psychiatric issues. The level of impact by COVID-19 on one's daily functioning is also positively associated with poor mental health. CONCLUSIONS: Our findings suggested no significant increase in the prevalence of psychiatric symptoms, following the first batch of students' return to school. These findings aim to complement the current understanding of the psychiatric impact of COVID-19 on students and assist school principals to plan their return-to-school approaches in a mental-health sensitive way.

Extraction of phenol in wastewater with annular centrifugal contactors.

Solvent extraction is an effective way to treat and recover the phenolic compounds from the high content phenolic wastewater at present. The experimental study on treating the wastewater containing phenol has been carried out with QH-1extractant (the amine mixture) and annular centrifugal contactors. The distribution ratio of phenol was 108.6 for QH-1-phenol system. The mass-transfer process of phenol for the system was mainly controlled by diffusion. When the flow ratio (aqueous/organic) was changed from 1/1 to 4/1, the rotor speed was changed from 2500 to 4000 r/min, and the total flow of two phases was changed from 20 to 70 mL/min, the mass-transfer efficiency E of the single-stage centrifugal contactor was more than 95%. When the flow ratio was changed from 4.4/1 to 4.9/1, the rotor speed was 3000 r/min, and the total flow of two phases was changed from 43.0 to 47.0 mL/min, the extraction rate rho of the three-stage cascade was more than 99%. When 15% NaOH was used for stripping of phenol in QH-1, the stripping efficiency of the three-stage cascade was also more than 99% under the experimental conditions.

Pain relief effect of breast feeding and music therapy during heel lance for healthy-term neonates in China: a randomized controlled trial.

OBJECTIVES: to test the effectiveness of breast feeding (BF), music therapy (MT), and combined breast feeding and music therapy (BF+MT) on pain relief in healthy-term neonates during heel lance. DESIGN: randomised controlled trial. SETTING: in the postpartum unit of one university-affiliated hospital in China from August 2013 to February 2014. PARTICIPANTS: among 288 healthy-term neonates recruited, 250 completed the trial. All neonates were undergoing heel lancing for metabolic screening, were breast fed, and had not been fed for the previous 30 minutes. INTERVENTIONS: all participants were randomly assigned into four groups - BF, MT, BF+MT, and no intervention - with 72 neonates in each group. Neonates in the control group received routine care. Neonates in the other three intervention groups received corresponding interventions five minutes before the heel lancing and throughout the whole procedure. MEASUREMENTS: Neonatal Infant Pain Scale (NIPS), latency to first cry, and duration of first crying. FINDINGS: mean changes in NIPS scores from baseline over time was dependent on the interventions given. Neonates in the BF and combined BF+MT groups had significantly longer latency to first cry, shorter duration of first crying, and lower pain mean score during and one minute after heel lance, compared to the other two groups. No significant difference in pain response was found between BF groups with or without music therapy. The MT group did not achieve a significantly reduced pain response in all outcome measures. CONCLUSIONS: BF could significantly reduce pain response in healthy-term neonates during heel lance. MT did not enhance the effect of pain relief of BF. IMPLICATIONS FOR PRACTICE: healthy-term neonates should be breast fed to alleviate pain during heel lance. There is no need for the additional input of classical music on breast feeding in clinic to relieve procedural pain. Nurses should encourage breast feeding to relieve pain during heel lance.

Predictors of breast feeding self-efficacy among Chinese mothers: a cross-sectional questionnaire survey.

OBJECTIVES: to examine breast feeding self-efficacy and identify its predictors among expectant Chinese mothers in the antenatal period. DESIGN AND SETTING: a cross-sectional descriptive questionnaire survey was conducted in the antenatal clinics of three university hospitals in China between September and December 2011. PARTICIPANTS: expectant mothers planning to breast feed, and who were at least 18 years of age, expecting a single, healthy, full-term baby, and competent in Mandarin (n=201). MEASUREMENTS: a socio-demographic data sheet, the Chinese version of the Breastfeeding Self-Efficacy Scale, and the Perceived Social Support Scale. FINDINGS: the expectant Chinese mothers reported moderate levels of breast feeding self-efficacy. Expectant mothers who had had previous experience in breast feeding, who had watched other mothers breast feed their infants, or who had made the decision to breast feed earlier reported higher breast feeding self-efficacy. Expectant mothers' perceived social support, perceived attitude of significant others, including husband, mothers, and friends, towards breast feeding are correlated with breast feeding self-efficacy. The best-fit regression analysis revealed five variables that explained 34% of the variance in breast feeding self-efficacy in the antenatal period: perceived social support, previous experience of breast feeding, previous experience of watching others breast feed, timing of maternal decision to breast feed, and perceived husband's attitude towards breast feeding. CONCLUSIONS: this study highlighted the importance of improving Chinese mothers' breast feeding self-efficacy by considering the main predictors found in this study. IMPLICATIONS FOR PRACTICE: health care professionals could develop strategies to promote breast feeding self-efficacy, such as providing opportunities for expectant mothers to learn from others' successful experience, adopt a family-centred approach in the provision of breast feeding education, provide breast feeding education at the beginning of pregnancy or even earlier, and rally comprehensive social support for expectant mothers.