Early Wake Research Articles

Sleep timing behaviour, sleep duration and adherence to obesogenic dietary patterns from pre-school to school age: results from the Portuguese birth cohort Generation XXI.

In an obesogenic environment, short sleeping may increase opportunistic eating. The timing of sleep might also influence the drive to eat. This study investigated the prospective association of sleep timing and duration with diet in 5286 children from the Portuguese birth cohort Generation XXI, evaluated at 4 and 7 years of age. At 4 years, sleep duration was categorised into ≤10 and >10 h. Four sleep timing categories were generated based on the median split for sleep-onset and -offset times: 'Early Sleep-Early Wake'; 'Early Sleep-Late Wake'; 'Late Sleep-Early Wake'; 'Late Sleep-Late Wake'. At 7 years, diet was obtained by a food frequency questionnaire and three dietary patterns were included: 'Healthier', 'Energy-Dense Foods (EDF)' and 'Snacking'. The Healthy Eating Index was used to evaluate diet quality. Multinomial logistic regression models and generalised linear models were performed. Children who had a late sleep, independently of the time of waking up, had higher odds of following the 'EDF' pattern, compared with the 'Healthier'. Boys who had late sleep and/or late wake had also higher odds of following the 'Snacking' pattern and had poorer diet quality. In both sexes, a late sleep or late wake were associated with a lower diet quality, compared to the group 'Early Sleep-Early Wake', and independently of nap behaviour. In boys, shorter sleep duration was associated with a poorer diet. In conclusion, pre-schoolers with late bedtimes or wake-up times have worse dietary patterns and poorer diet quality at the age of 7 years, which seems to be independent of sleep duration.

Sleep duration and perceptions of sleep quality in British Army recruits during basic training - an observational analysis.

Sleep is critical to the health, wellbeing and performance of military personnel during basic training. This two-part study evaluated sleep-wake patterns and sleep disturbances in junior soldiers (JS) and infantry recruits in Autumn 2021 (study 1), and non-infantry recruits in spring 2022 (study 2). During studies 1 and 2, validated wearable technology combined with a sleep diary was used to quantify sleep-wake indices, sleep disturbances and perceptions of sleep quality. Sleep diary data was analysed descriptively. A series of repeated-measures ANOVAs examined differences in objective sleep-wake indices. Correlation analysis determined associations between time in bed (TIB) and total sleep time (TST). Significant (p < 0.05) differences in most sleep-wake indices were observed between weeks of basic training for all cohorts. Strong positive correlations between TIB and TST were observed for each cohort across basic training (r = 0.681 - 0.970, p < 0.001), with longer TST associated with greater TIB. The mean±SD sleep duration (hours and mins [hm]) for JS (06:22 ± 00:27hm), non-infantry (05:41 ± 00:47hm) and infantry (05:46 ± 00:34hm) recruits across basic training was consistently below national recommendations. The mean±SD bed and wake times for JS (bedtime: 23:01 ± 00:32hm; awake: 05:34 ± 00:10hm), non-infantry (bedtime: 23:38 ± 01:09hm; awake: 04:47 ± 00:58hm), and infantry (bedtime: 23:13 ± 00:29hm; awake: 05:38 ± 00:26hm) recruits varied across weeks of basic training, with over 80% reporting "fairly bad" or "very bad" sleep quality and frequent periods of "dozing off" during daytime activity. The most commonly reported sleep disturbing factors identified during basic training involved: late-night military admin (e.g., ironing, boot cleaning, kit set up etc), early morning wake times, extraneous noise, light and hot room temperatures within the primary sleeping environment, bed/mattress discomfort, muscle soreness and feelings of stress and anxiety. Our findings contribute to the existing evidence that long-term sleep loss is pervasive during initial military training programmes. The average sleep durations indicate chronic and unrecoverable sleep loss which would be expected to significantly impair physical and cognitive military performance, and increase the risk of injury, illness and attrition rates during basic training. Changes in the design and scheduling of basic training programmes to enable, at the least, minimum sleep recommendations to be met, and to improve sleep hygiene in the primary sleeping environment are warranted.

Sleep restriction by sleep timing late night or early wake: The impact on physical activity and dietary intake in adults

PurposeTo date, few studies have assessed whether the timing of sleep restriction impacts physical activity and energy intake patterns. Thus, we aimed to quantify physical activity and energy intake during an early wake (EW) and late sleep (LS) period. MethodsFourteen participants who met the inclusion criteria (sleep 7–9 h/night and a BMI of <40 kg/m2) participated in 3 crossover free-living conditions: normal sleep (NS, 7–9 h), EW (2-h early wake-time), and LS (2-h late to sleep) for 4 nights. Sleep duration (via Actiwatch), energy intake (via food diaries), and physical activity (via hip accelerometry) were recorded for 4 days/4 nights throughout each condition. ResultsSleep duration was reduced in both sleep restriction conditions compared to NS (p < 0.001) with no difference between sleep restriction conditions. Daily energy intake tended to increase in the LS condition (p = 0.056) but was unchanged during EW (p = 0.56). Fat (p = 0.031) and sodium (p = 0.039) intake were increased in the LS condition only compared to NS. During the EW condition, fat (p = 0.24) and sodium (p = 0.18) intake were not altered. No changes in carbohydrate or protein intake occurred between conditions. Daily steps tended to increase in the EW condition compared to NS (p = 0.058), while steps during the LS condition were unchanged (p = 0.28), with no differences between sleep restriction conditions. ConclusionThe timing of sleep curtailment differentially influences physical activity and EI the following day, such that EW results in increased physical activity, while LS leads to poorer dietary choices.

Fall Risk, Sleep Behavior, and Sleep-Related Movement Disorders in Young Urbanites Exposed to Air Pollution.

Quadruple aberrant hyperphosphorylated tau, amyloid-β, α-synuclein, and TDP-43 pathology had been documented in 202/203 forensic autopsies in Metropolitan Mexico City ≤40-year-olds with high exposures to ultrafine particulate matter and engineered nanoparticles. Cognition deficits, gait, equilibrium abnormalities, and MRI frontal, temporal, caudate, and cerebellar atrophy are documented in young adults. This study aimed to identify an association between falls, probable Rapid Eye Movement Sleep Behavior Disorder (pRBD), restless leg syndrome (RLS), and insomnia in 2,466 Mexican, college-educated volunteers (32.5±12.4 years). The anonymous, online study applied the pRBD and RLS Single-Questions and self-reported night-time sleep duration, excessive daytime sleepiness, insomnia, and falls. Fall risk was strongly associated with pRBD and RLS. Subjects who fell at least once in the last year have an OR = 1.8137 [1.5352, 2.1426] of answering yes to pRBD and/or RLS questions, documented in 29% and 24% of volunteers, respectively. Subjects fell mostly outdoors (12:01 pm to 6:00 pm), 43% complained of early wake up hours, and 35% complained of sleep onset insomnia (EOI). EOI individuals have an OR of 2.5971 [2.1408, 3.1506] of answering yes to the RLS question. There is a robust association between falls, pRBD, and RLS, strongly suggesting misfolded proteinopathies involving critical brainstem arousal and motor hubs might play a crucial role. Nanoparticles are likely a significant risk for falls, sleep disorders, insomnia, and neurodegenerative lethal diseases, thus characterizing air particulate pollutants' chemical composition, emission sources, and cumulative exposure concentrations are strongly recommended.

The unsteady wake transition behind a wall-mounted large-depth-ratio prism

The wake of a long rectangular wall-mounted prism is investigated at Reynolds numbers of $Re=250\unicode{x2013}1200$ by directly solving the Navier–Stokes equations. The aim of this study was to examine the unsteady transition mechanism in the wake of a large-depth-ratio (streamwise length to width) prism as well as to characterize the unsteady wake evolution at low Reynolds numbers. The results highlighted that increasing Reynolds number significantly altered the dominance of upwash and downwash flows in the time-averaged flow and changed the characteristics of coherent structures, including their size, dominant frequency and interaction with other structures in the flow. The wake is, therefore, categorized into three regimes within the transition process: steady regime at $Re \leq 625$ , regular unsteady regime at $625 &lt; Re &lt; 750$ and irregular unsteady regime at $Re \geq 750$ . Particularly, the wake started to exhibit unsteady features at $Re=625\unicode{x2013}650$ , which transitioned to an early irregular unsteady wake topology at $Re=750$ . At $Re \geq 675$ , horseshoe vortices transformed to vortex loops. There were hairpin-like structures formed on the upper and side faces of the long prism. The results further indicated that the transition to unsteadiness is attributed to separated leading-edge shear-layer instabilities and interactions of the shear layer with the horseshoe structures. The wake was more complex due to the interactions of multiple coherent structures in the flow, which resulted in a multiple-periodicity wake system. A skeleton model is proposed for a large-depth-ratio prism, to incorporate details of the unsteady flow features and specify various flow coherent structures at low Reynolds numbers.

Circadian rhythm shifts and alcohol access in adolescence synergistically increase alcohol preference and intake in adulthood in male C57BL/6 mice

BackgroundAdolescents have a natural tendency to be night owls, maintaining delayed circadian rhythms, and this rhythm is in direct conflict with the early wake times required during the school year. This leads to ‘social jetlag’, chronic circadian stress or desynchrony (CD) in which the rhythm of the intrinsic body clock is out of sync with behavior. CD increases alcohol intake in adolescents and adults, yet it is unknown whether adolescent CD also increases long-term addiction risk. The goal of this study was to determine whether adolescent alcohol intake in CD would increase adult alcohol preference and intake in male C57BL/6 J mice. Methods: We measured free access alcohol intake, water intake, and wheel-running activity during a normal 12 h (h) baseline photoperiod and then during shifting lighting schedules (Experiment 1) or a shortened circadian day (Experiment 2). Results: In Experiment 1, altered lighting produced a persistent increase in adolescent alcohol intake and in binge-like drinking (drinking at least 5 licks per minute, with no more than a 1 min break in drinking) in adulthood, but only a transient increase in total alcohol intake for the first week after alcohol was reintroduced in adulthood. In Experiment 2, the circadian shift produced a significant increase in alcohol intake in both adolescence and adulthood. Molecular analysis demonstrated changes in plasma corticosterone and neuronal markers of stress and addiction at the conclusion of these experiments in the CD and alcohol-exposed groups. Conclusions: Thus, we conclude that circadian stress during adolescence is sufficient to produce a long-lasting susceptibility to alcohol use.

Supersonic cylinder wake dynamics

The supersonic wake of a circular cylinder in Mach 3 flow was studied through high-speed, focussing schlieren photography. The mean and unsteady behaviour of the separated shear layers, the reattachment process, the recompression wave and the early wake are analysed, and discussed in detail. The fluctuations in the wake are stronger and more coherent than those within the approaching shear layers and the recirculation region. The recompression of the shear layers energises the finer scales in the flow which leads to a departure from a $-$ 1 spectral roll-off observed in the schlieren spectra further upstream. The recompression wave exhibits low-frequency unsteadiness and a ripple-type motion which occurs as it is perturbed by shocklets radiating from the coherent structures in the wake. The wake consists of coherent disturbances with the same characteristic frequency as that for an incompressible flow over a cylinder; however, this instability is suppressed as the wake accelerates, presumably due to increasing compressibility. The primary instability of the wake flow has a characteristic frequency nearly twice that of its incompressible counterpart and it is shown to be driven by the presence of aeroacoustic resonance in the wake. It is also shown that the resonance, which leads to the formation of broadband standing waves in the wake, is the result of an interaction between the wake instabilities and upstream propagating acoustic waves in the wake. The acoustic waves originate upstream of the reattachment region and are believed to be generated by the unsteady separation on the cylinder surface.

Laboratory and numerical experiments on the near wake of a sphere in a stably stratified ambient

The flow around and behind a sphere in a linear density gradient has served as a model problem for both body-generated wakes in atmospheres and oceans, and as a means of generating a patch of turbulence that then decays in a stratified ambient. Here, experiments and numerical simulations are conducted for 20 values of Reynolds number, $Re$ , and internal Froude number, $Fr$ , where each is varied independently. In all cases, the early wake is affected by the background density gradient, notably in the form of the body-generated lee waves. Mean and fluctuating quantities do not reach similar states, and their subsequent evolution would not be collapsible under any universal scaling. There are five distinguishable flow regimes, which mostly overlap with previous literature based on qualitative visualisations and, in this parameter space, they maintain their distinguishing features up to and including buoyancy times of 20. The possible relation of the low $\{Re, Fr\}$ flows to their higher $\{Re, Fr\}$ counterparts is discussed.

Insulin resistance and sleep complains in ten years follow-up

Abstract Background The serious health consequence that comes from disrupted and poor sleep quality is an increased risk for cardiac diseases and diabetes. The goal was to investigate the association of insulin resistance with sleep complains in ten years follow-up. Methods A randomized epidemiological follow up study with 835 subjects: 300 (35.9%) men and 535 (64.1%) women was performed in 2003 and in 2013. The Basic Nordic Sleep Questionnaire was used to assess the frequency of sleep complaints in the first and the follow up survey. Insulin resistance was evaluated by homeostasis model assessment of insulin resistance (HOMA-IR). The contingent was divided into 2 groups: insulin resistance group (HOMA-IR&amp;gt; 2.7) 33% and No- insulin resistance group (HOMA-IR ≤2.7) 67%. Results A statistically significantly increased number of persons with diabetes mellitus and high body mass index was seen in both groups after 10-year period; however, in insulin resistance group an increase was more expressed. A statistically significant change of sleep complains after 10-year period was seen in insulin resistance group; while in no-insulin resistance group there were no significant modifications. Individuals with insulin resistance were more likely to complain of difficulty falling asleep (from 11.2% to 17.8%, p = 0.031) and early wake up in the morning (from 12.6% to 24.5%, p = 0.003) after 10-year period. Daytime sleepiness was also more frequently observed among persons with insulin resistance (from 9.0% to 14.7, p = 0.037). They were more likely to use sleeping pills (from 4.0% to 8.3%, p = 0.034) and, not surprisingly, were more likely to use alcohol to improve sleep (from 1.1% to 4.4%, p = 0.012). Conclusions A statistically significant increase in body mass index and diabetes as well as difficulty to fall asleep, early waking up in the morning, severe drowsiness in the morning and daytime sleepiness was found in ten years follow-up in insulin resistance group. Key messages A statistically significant increase of sleep complains after ten years follow-up was seen in insulin resistance group. Insulin resistance and metabolic syndrome in parallel with disturbed sleep may lead to the development of diabetes in follow-up.

Relationship between work context and sleep problems of high school teachers

Objective: The teaching function is related to work overload and health problems, including sleep problems. However, is there a relationship between sleep problems and aspects of work? In view of this, this study aimed to assess the relationship between the work context, the quality of sleep and the daytime sleepiness of teachers from public schools in Rio Grande do Norte (RN). Methodology: This study was conducted in 9 schools with 61 teachers of both genders who filled the work context assessment scale, the Pittsburgh Sleep Quality Index and the Epworth Sleepiness Scale. Results and Discussion: The majority evaluated Working Conditions and Work Organization as critical/severe, and half of them considered Socio-Professional Relations as critical/severe. Poor sleep quality was observed in 69% of teachers, regardless of gender and excessive daytime sleepiness was observed in 49% of teachers, most often in women (55%) compared to men. Nevertheless, there was no significant relationship between work context and sleep problems. In relation to sleep schedule, it was observed that teachers present late sleep time (23: 26 ± 1: 25h) and early wake up time (6: 06 ± 1: 16h) which may have resulted in short sleep duration (6: 10 ± 1: 07h). Conclusion: These results demonstrate that, in general, public school teachers in RN present complaints related to the work context and sleep problems. However, studies with a more representative sample are needed to assess as the factors related to the work context may be contributing to sleep problems. Furthermore, there is a need to create spaces for discussion with teachers in order to improve the work context and public policies aimed at education.

Efficacy of melatonin for sleep disturbance in middle-aged primary insomnia: a double-blind, randomised clinical trial

BackgroundThe aim of this study was to determine the efficacy of exogenous melatonin supplementation for sleep disturbances in patients with middle-aged primary insomnia. MethodsThis is a randomized double-blind, placebo-controlled parallel study. Participants were recruited from Tianlin community, Xuhui district, Shanghai. Ninety-seven consecutive middle-aged patients with primary insomnia were randomized to receive 3 mg fast-release melatonin (n = 51) or placebo (n = 46) for four-weeks. Objective sleep parameters tested by overnight polysomnography, subjective sleep performance and daytime somnolence obtained from the Pittsburgh Sleep Quality Index (PSQI), Insomnia Severity Index (ISI) and Epworth Sleepiness Scale (ESS) were obtained at baseline and after treatment. Treatment was taken daily 1 h before bedtime. Serious adverse events and side-effects were monitored. ResultsMelatonin supplementation significantly decreased early wake time [−30.63min (95% CI, −53.92 to −7.34); P = 0.001] and percentage of N2 sleep [−7.07% (95% CI, −13.47% to −0.68%); P = 0.031]. However, melatonin had no significant effect on other objective sleep parameters including sleep latency, sleep efficiency, wake during the sleep and percent of N1, N3 and REM sleep. Melatonin had no effect on insomnia symptoms and severity on the PSQI [1.53(95% CI, −0.55 to 3.61); p = 0.504]; ISI [0.81 (95% CI, −2.27 to 3.88); p = 0.165] and ESS [−0.83 (95% CI, −3.53 to 1.88); p = 0.147]. No serious adverse events were reported. ConclusionsMelatonin supplementation over a four-week period is effective and safe in improving some aspects of objective sleep quality such as total sleep time, percentage of rapid eye movement and early morning wake time in middle-aged patients with insomnia. Trial registrationIdentifier: ChiCTR-TRC-13003997; Prospectively registered on 2 December 2013.

When Bitcoin has the flu: on Bitcoin’s performance to hedge equity risk in the early wake of the COVID-19 outbreak

ABSTRACT Using the coronavirus COVID-19 outbreak as a set-up for a quasi-experiment, this study derives novel insights on the dynamic correlation between Bitcoin and US stocks. Given the unprecedented scale of infections and the nature of the virus, the potential impact on the dynamic correlation was unpredictable and therefore uncertain. Using a difference-in-differences setting, the dynamic correlation between Bitcoin and stocks is controlled for the dynamic correlation between gold and stocks. This study finds that Bitcoin performed poorly in hedging this tail risk.

Time to Take Sleeping Pills and Subjective Satisfaction among Cancer Patients

ObjectiveWe investigated the influence of the time to take hypnotics and daytime activity on patient satisfaction with sleeping pills. MethodsNinety-six cancer patients who were currently taking benzodiazepine or z-drug as hypnotics were grouped into satisfied and dissatisfied groups. The subjects’ symptoms, time to take sleeping pills, bedtime, sleep onset time, wake up time, and time in bed within 24 hours (TIB/d) were obtained. ResultsThe satisfied group had significantly late sleeping pill ingestion time (p=0.04); significantly early wake up time (p=0.01); and significantly shorter sleep latency, TIB/d, duration from the administration of pills to sleep onset, and duration from the administration of pills to wake up time (PTW). Logistic regression analysis revealed that the significant predictors of patient satisfaction to hypnotics were less severity of insomnia [odds ratio (OR)=0.91] and the time variables, including late sleeping pill administration time (OR=1.53) and early wake up time (OR=0.57). Among the duration variables, short PTW (OR=0.30) and short TIB/d (OR=0.64) were significantly related with the satisfaction to hypnotics. ConclusionReducing the duration from the administration of hypnotics to wake up time and TIB/d can influence the satisfaction to sleeping pills.

Living Without Temporal Cues: A Case Study.

Isolation from external time cues allows endogenous circadian rhythmicity to be demonstrated. In this study, also filmed as a television documentary, we assessed rhythmic changes in a healthy man time isolated in a bunker for 9 days/nights. During this period the lighting conditions were varied between: (1) self-selected light/dark cycle, (2) constant dim light, and (3) light/dark cycle with early wake up. A range of variables was assessed and related to the sleep-wake cycle, psychomotor and physical performance and clock-time estimation. This case study using modern non-invasive monitoring techniques emphasizes how different physiological circadian rhythms persist in temporal isolation under constant dim light conditions with different waveforms, free-running with a period (τ) between 24 and 25 h. In addition, a significant correlation between time estimation and mid-sleep time, a proxy for circadian phase, was demonstrated.

When Bitcoin Has the Flu: On Bitcoin’s Performance to Hedge Equity Risk in the Early Wake of the COVID-19 Outbreak

Using the coronavirus COVID-19 outbreak as a set-up for a quasi-experiment, this study derives novel insights on the dynamic correlation between Bitcoin and U.S. stocks. Given the unprecedented scale of infections and the nature of the virus, the potential impact on the dynamic correlation was unpredictable and therefore uncertain. Using a difference-in-differences setting, the dynamic correlation between Bitcoin and stocks is controlled for the dynamic correlation between gold and stocks. This study finds that Bitcoin performed poorly in hedging this tail risk.

Sleep duration, timing, variability and measures of adiposity among 8- to 12-year-old children with obesity.

SummaryObjectivesSleep disruption in laboratory studies increases adiposity and decreases glucose tolerance. However, few epidemiological studies have used objective measures of sleep. This study aims to assess associations between sleep duration, timing and regularity with measures of adiposity.MethodsThis is a cross‐sectional study of 188 children with obesity (age: 10.50 ± 1.39 years; body mass index: 29.24 ± 5.04 kg m−2). Nightly sleep duration, bedtime and wake time were measured by multiple‐day actigraphy and parent reports. Per cent overweight (per cent over median body mass index for age and sex) was chosen as the primary measure of obesity status. Objective measures of height, weight, waist circumference, blood pressure, fasting blood lipids, glucose, insulin, glycated haemoglobin and C‐reactive protein were obtained. Television screen time and total caloric intake were assessed via parent questionnaire.ResultsEach hour later in weekday bedtime was associated with an additional 6.17 per cent overweight (95% confidence interval [CI]: 1.42–10.92). Each hour greater in day‐to‐day variability in weekday bedtime and weekday wake time was associated with an additional 10.20 (95% CI: 0.50–19.91) and 10.02 (95% CI: 1.55–18.50) per cent overweight, respectively. Associations were similar after controlling for other obesity‐related behaviours (television screen time, total caloric intake and physical activity.)ConclusionsAmong children with obesity, later bedtime and greater variability in bedtime and wake time are associated with greater adiposity, independent of other obesity‐related behaviours. Early bedtime and wake time and consistent day‐to‐day sleep timing may be strategies to reduce adiposity in high‐risk children.

Parent-child co-sleeping in children with co-morbid conditions and sleep-disordered breathing.

Co-sleeping is common in children with co-morbid conditions. The aim of the study was to analyze the prevalence and determinants of parent-child co-sleeping in children with co-morbid conditions and sleep-disordered breathing and the impact on parental sleep. Parents of consecutive children undergoing a sleep study filled in a questionnaire on co-sleeping. The parents of 166 children (80 boys, median age 5.7years (0.5-21) participated in this study. The most common co-morbid conditions of the children were Down syndrome (17%), achondroplasia (11%), and Chiari malformation (8%). The prevalence of parent-child co-sleeping was 46%. Reasons for co-sleeping were mainly reactive and included child's demand (39%), crying (19%), nightmares (13%), medical reason (34%), parental reassuring or comforting (27%), and/or over-crowding (21%). Sixty-eight percent of parents reported that co-sleeping improved their sleep quality because of reassurance/comforting (67%), reduced nocturnal awakening (23%), and child supervision (44%). Forty percent of parents reported that co-sleeping decreased their sleep quality because of nocturnal awakenings or early wake up, or difficulties initiating sleep (by 77% and 52% of parents, respectively), whereas both positive and negative associations were reported by 29% of the parents. Co-sleeping was more common with children < 2years of age as compared to older children (p < 0.001). Parent-child co-sleeping is common in children with co-morbid conditions and sleep-disordered breathing. Co-sleeping was mainly reactive and had both positive and negative associations with parental sleep quality. Co-sleeping should be discussed on an individual basis with the parents in order to improve the sleep quality of the family.

청소년의 규칙적 아침식사를 위한 수면 관련 요인 분석

PurposeBreakfast is the most important meal to provide energy for the day. Breakfast is especially important to give enough nutritional support to children and adolescents for their physical growth and sexual development. Sleep-related factors like average sleep duration and wake up time would mostly be associated with regular breakfast. This study aimed to investigate the effect of sleep on regular breakfast consumption in Korean adolescents. MethodsThe study used the data from the 12th Korea Youth Risk Behavior Web-based Survey (KYRBS-XII) conducted in 2016 by the Korea Centers for Disease Control and Prevention. The data of 62,820 subjects (middle/high school students) were included in the final analysis. The study examined the factors related to regular breakfast, focusing on weekday average sleep duration and wake up time of middle school students and high school students, respectively. ResultsRegular breakfast consumption was shown to have a statistically significant association with high economic status, nutritional education, weekday average sleep duration, wake up time, and subjective sleep satisfaction in the multivariate logistic regression. Regardless of the school level, regular breakfast consumption was significantly associated with early wake up time. As to the effect of weekday average sleep duration on regular breakfast consumption, it showed some different results depending on the school level. ConclusionRegular breakfast consumption of Korean adolescents was related to weekday average sleep duration and wake up time. Having breakfast regularly was affected by both adequate weekday average sleep duration and early wake up time.

PENANAMAN NILAI-NILAI KARAKTER PESERTA DIDIK DI SMA NEGERI 1 PADANG PANJANG

This study was aimed at describing the strategy on building the students’ character values in high school 1 Padang Panjang. This study was qualitative by using interview, documentation and observation as instruments. The results revealed that the strategy on upgrading students’ character were applied in intracurricular and extracurricular. In intracurricular, there was morning mentoring program. In extracurricular, there were educational building through small group; night mentoring; Islamic orientation; memorizing quran; Friday praying; annual islamic day; Islamic hiking; Islamic Study Tour (IST); and Ramadhan School. To upgrade the students’ independent, the programs applied were 1) cleaning class; 2) cleaning room; 3) early wake up for praying tahajjud and subuh; 4) washing own clothes. Keywords: Strategy, Students’ Character Values, High School, Padang Panjang

A Cryptochrome 2 mutation yields advanced sleep phase in humans.

Familial Advanced Sleep Phase (FASP) is a heritable human sleep phenotype characterized by very early sleep and wake times. We identified a missense mutation in the human Cryptochrome 2 (CRY2) gene that co-segregates with FASP in one family. The mutation leads to replacement of an alanine residue at position 260 with a threonine (A260T). In mice, the CRY2 mutation causes a shortened circadian period and reduced phase-shift to early-night light pulse associated with phase-advanced behavioral rhythms in the light-dark cycle. The A260T mutation is located in the phosphate loop of the flavin adenine dinucleotide (FAD) binding domain of CRY2. The mutation alters the conformation of CRY2, increasing its accessibility and affinity for FBXL3 (an E3 ubiquitin ligase), thus promoting its degradation. These results demonstrate that CRY2 stability controlled by FBXL3 plays a key role in the regulation of human sleep wake behavior.