scholarly journals A global quantification of “normal” sleep schedules using smartphone data

2016 ◽  
Vol 2 (5) ◽  
pp. e1501705 ◽  
Author(s):  
Olivia J. Walch ◽  
Amy Cochran ◽  
Daniel B. Forger
Keyword(s):  
Laboratory Experiments ◽  
Population Level ◽  
Light Level ◽  
Sleep Scheduling ◽  
Sleep Habits ◽  
Wake Time ◽  
Sleep Timing ◽  
The World ◽  
Primary Determinant ◽  
Normal Sleep

The influence of the circadian clock on sleep scheduling has been studied extensively in the laboratory; however, the effects of society on sleep remain largely unquantified. We show how a smartphone app that we have developed, ENTRAIN, accurately collects data on sleep habits around the world. Through mathematical modeling and statistics, we find that social pressures weaken and/or conceal biological drives in the evening, leading individuals to delay their bedtime and shorten their sleep. A country’s average bedtime, but not average wake time, predicts sleep duration. We further show that mathematical models based on controlled laboratory experiments predict qualitative trends in sunrise, sunset, and light level; however, these effects are attenuated in the real world around bedtime. Additionally, we find that women schedule more sleep than men and that users reporting that they are typically exposed to outdoor light go to sleep earlier and sleep more than those reporting indoor light. Finally, we find that age is the primary determinant of sleep timing, and that age plays an important role in the variability of population-level sleep habits. This work better defines and personalizes “normal” sleep, produces hypotheses for future testing in the laboratory, and suggests important ways to counteract the global sleep crisis.

scholarly journals Sleep quality, timing, and psychological difficulties in Italian school-age children and their mothers during COVID-19 lockdown

2020 ◽  
Author(s):  
Nicola Cellini ◽  
Elisa Di Giorgio ◽  
Giovanna Mioni ◽  
Daniela Di Riso
Keyword(s):  
Sleep Quality ◽  
Online Survey ◽  
School Age Children ◽  
School Age ◽  
Sleep Habits ◽  
Wake Time ◽  
Sleep Timing ◽  
Psychological Difficulties ◽  
Smart Working ◽  
Temporary Closure

Background. By March 10th, 2020, the Italian Government has ordered a national lockdown to limit viral transmission of COVID-19 infection, which establishes home confinement, movement restriction, home (smart) working, and temporary closure of non-essential businesses and schools of every order and degree. The current study investigated how these restrictive measures impacted sleep quality, timing, and psychological difficulties in school-age children and their mothers during the lockdown.Methods. Using an online survey, 299 mothers reported their sleep habits (timing, quality, quantity), time experience, and psychological difficulties (emotional and behavioral) and of those of their children (6-10 yrs old) during the home confinement and, retrospectively, before the lockdown. Results. During the lockdown, children showed a marked delay in sleep timing, i.e., later bedtime and wake time, and a mild worsening in sleep quality. They were less prone to respect the daily routines and to keep track of the passage of time. We also observe increased emotional, conduct, and hyperactive symptoms, and the increase in these psychological difficulties was predicted by the change in sleep quality, boredom, and mothers’ psychological difficulties. Also, mothers showed a delayed sleep timing and worsening of sleep quality during the lockdown, which degree varied depending on their working conditions. Mothers who kept working regularly outside their home during the lockdown reported a more regular sleep pattern, whereas mothers who stopped working showed more emotional symptoms and relevant changes in their time perception. Conclusions. Overall, given the evidence of the adverse behavioral and psychological impact of home confinement and social restrictions, effective measures are needed to be in place to mitigate their long-term effects on children and their mothers, especially those in the smart working condition.

Ups and Downs

2018 ◽  
Author(s):  
Roy Livermore
Keyword(s):  
Mantle Convection ◽  
Laboratory Experiments ◽  
Inner Core ◽  
Computer Modelling ◽  
Great Depth ◽  
New Horizons ◽  
The Core ◽  
The Earth ◽  
The World ◽  
The 1960S

Despite the dumbing-down of education in recent years, it would be unusual to find a ten-year-old who could not name the major continents on a map of the world. Yet how many adults have the faintest idea of the structures that exist within the Earth? Understandably, knowledge is limited by the fact that the Earth’s interior is less accessible than the surface of Pluto, mapped in 2016 by the NASA New Horizons spacecraft. Indeed, Pluto, 7.5 billion kilometres from Earth, was discovered six years earlier than the similar-sized inner core of our planet. Fortunately, modern seismic techniques enable us to image the mantle right down to the core, while laboratory experiments simulating the pressures and temperatures at great depth, combined with computer modelling of mantle convection, help identify its mineral and chemical composition. The results are providing the most rapid advances in our understanding of how this planet works since the great revolution of the 1960s.

From Silent Spring to The Frog of War

2017 ◽  
Author(s):  
David K. Skelly
Keyword(s):  
Natural History ◽  
Laboratory Experiments ◽  
Wild Populations ◽  
Rachel Carson ◽  
Chemical Agents ◽  
Silent Spring ◽  
The World ◽  
History Information ◽  
Wildlife Populations ◽  
The Impact

This chapter presents two examples to demonstrate that natural history is the necessary basis of any reliable understanding of the world. More than a half century ago, Rachel Carson revolutionized the public’s view of pesticides. The foundation of her success was the careful use of natural history data, collated from across North America. The examples she assembled left little doubt that DDT and other pesticides were causing a widespread decline in birds. More recently, the case for the impact of atrazine on wildlife was based on laboratory experiments, without the advantage of natural history observations. For atrazine, natural history observations now suggest that other chemical agents are more likely to be responsible for feminization of wildlife populations. Developing expectations for scientists to collect natural history information can help to avoid over-extrapolating lab results to wild populations, a tendency often seen when those lab results conform to preconceptions about chemicals in the environment.

scholarly journals The effects of seasons and weather on sleep patterns measured through longitudinal multimodal sensing

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Stephen M. Mattingly ◽  
Ted Grover ◽  
Gonzalo J. Martinez ◽  
Talayeh Aledavood ◽  
Pablo Robles-Granda ◽  
...  
Keyword(s):  
Sleep Duration ◽  
Seasonal Effects ◽  
Sleep Patterns ◽  
Sleep Habits ◽  
Sleep Behavior ◽  
Weather Effects ◽  
Wake Time ◽  
Multimodal Sensing ◽  
Four Seasons ◽  
Local Weather

AbstractPrevious studies of seasonal effects on sleep have yielded unclear results, likely due to methodological differences and limitations in data size and/or quality. We measured the sleep habits of 216 individuals across the U.S. over four seasons for slightly over a year using objective, continuous, and unobtrusive measures of sleep and local weather. In addition, we controlled for demographics and trait-like constructs previously identified to correlate with sleep behavior. We investigated seasonal and weather effects of sleep duration, bedtime, and wake time. We found several small but statistically significant effects of seasonal and weather effects on sleep patterns. We observe the strongest seasonal effects for wake time and sleep duration, especially during the spring season: wake times are earlier, and sleep duration decreases (compared to the reference season winter). Sleep duration also modestly decreases when day lengths get longer (between the winter and summer solstice). Bedtimes and wake times tend to be slightly later as outdoor temperature increases.

scholarly journals Mental health and sleep habits/problems in children aged 3–4 years: a population study

2021 ◽  
Vol 15 (1) ◽  
Author(s):  
Fumie Horiuchi ◽  
Kentaro Kawabe ◽  
Yasunori Oka ◽  
Kiwamu Nakachi ◽  
Rie Hosokawa ◽  
...  
Keyword(s):  
Mental Health ◽  
Health Status ◽  
Healthcare Providers ◽  
Poor Mental Health ◽  
Mental Health Status ◽  
Control Group ◽  
Sleep Habits ◽  
Psychological Burden ◽  
Wake Time ◽  
Health Group

Abstract Background Sleep is essential for mental health at all ages, but few studies have investigated the importance of sleep for mental health in early childhood. Therefore, this study examined the association between mental health and sleep habits/problems in children aged 3–4 years. Methods Children aged 3 to 4 years who were living in the community (n = 415; 211/204 boys/girls) were recruited for this study. Their mental health was assessed using the Strengths and Difficulties Questionnaire (SDQ), and their sleep habits/problems were evaluated using the Child and Adolescent Sleep Checklist. Results Based on the total difficulties score of the SDQ, the children were divided into two groups: a poor mental health group (n = 76) and a control group (n = 339). In terms of sleep habits, which included total sleep time, bedtime, wake time, and nap conditions, there were no differences between the two groups. Regarding sleep-related problems, however, anxiety before going to sleep (p = 0.026), circadian rhythm abnormalities (p = 0.014), and sleepiness during classes outside of naptimes (p = 0.031) were significantly higher in the poor mental health group than in the control group. Multiple regression analysis showed that poor mental health status was significantly associated with sleepiness and snoring (p = 0.017 and p = 0.018, respectively). Conclusions The mental health status of 3–4-year-old children was associated with sleep-related problems, namely sleepiness and snoring. Healthcare providers should pay attention to children’s irregular sleep-wake patterns; moreover, interventions for appropriate sleep hygiene will reduce the psychological burden on both children and their families.

scholarly journals Patterns of variation in the rDNA cistron within and among world populations of a mosquito, Aedes albopictus (Skuse).

Genetics ◽  
1989 ◽  
Vol 121 (3) ◽  
pp. 539-550
Author(s):  
W C Black ◽  
D K McLain ◽  
K S Rai
Keyword(s):  
Aedes Albopictus ◽  
Local Population ◽  
Population Level ◽  
Restriction Map ◽  
Repeat Region ◽  
Molecular Drive ◽  
Nontranscribed Spacer ◽  
Coding Regions ◽  
The World ◽  
Ribosomal Cistron

Abstract A restriction map was constructed of the ribosomal cistron in a mosquito, Aedes albopictus (Skuse). The 18s, 28s and nontranscribed spacer (NTS) regions were subcloned and used to probe for intraspecific variation. Seventeen populations were examined throughout the world range of the species. No variation was detected in the coding regions but extensive and continuous variation existed in the NTS. The NTS consisted of two nonhomologous regions. The first region contained multiple 190-bp AluI repeats nested within larger XhoI repeats of various sizes. There was a large number of length variants in the AluI repeat region of the NTS. No repeats were found in the second region and it gave rise to relatively fewer variants. An analysis of NTS diversity in individual mosquitoes indicated that most of the diversity arose at the population level. Discriminant analysis was performed on spacer types in individual mosquitoes and demonstrated that individuals within a population carried a unique set of spacers. In contrast with studies of the NTS in Drosophila populations, there seems to be little conservation of spacers in a population. The importance of molecular drive relative to drift and selection in the generation of local population differentiation is discussed.

Does Chronotype explain Daily Timing of Music Behaviors?

2021 ◽  
Author(s):  
Shannon Wright ◽  
Caroline Palmer
Keyword(s):  
Social Interaction ◽  
Daily Activity ◽  
Music Performance ◽  
Sleep Onset ◽  
Time Of Day ◽  
Sleep Diary ◽  
Sleep Habits ◽  
Sleep Timing ◽  
Music Making ◽  
Daily Changes

We addressed how circadian rhythms influence daily musical activities of performing musicians, who exhibit fine temporal control. Music performances often occur in the evening and late at night; evidence suggests that composing musicians tend to be later chronotypes than non-composing musicians. However, chronotype and daily music-making in performing musicians have yet to be investigated. The current study examined chronotype in actively practicing and/or performing musicians and non-musicians, and whether it was related to the daily timing of music performance. To test influences of daily changes due to the global COVID-19 pandemic, disruptions to musical, athletic, social, and sleep habits were also measured. Performing musicians, active (practicing but non-performing) musicians, inactive musicians, and non-musicians, residing in Canada, completed a 7-day online daily activity and sleep diary in Summer 2020. There were more evening chronotypes than morning chronotypes in the sample. Active/performing musicians tended to be earlier chronotypes than all other groups. Musicians' chronotype, but not nightly sleep timing, predicted the time of day that musicians made music: Late chronotypes made music later in the day and early chronotypes made music earlier in the day. Music performance and practice amount decreased during the COVID-19 period, but the daily timing of these activities did not change. All participants reported later sleep onset during the COVID-19 period; the amount of social interaction decreased during the COVID-19 period, while exercise increased for some and decreased for others. No changes in the daily timing of exercise, social interaction, or morning wake-up were reported. These findings suggest that performing musicians may be slightly earlier chronotypes than non-performing musicians and non-musicians, despite music performances often occurring in the evening. Chronotype was related to the time of day of music-making independent of nightly sleep timing, suggesting that times of day for making music reflect an individual's circadian rhythm.

The “is-ought fallacy” fallacy

2011 ◽  
Vol 34 (5) ◽  
pp. 262-263 ◽  
Author(s):  
Mike Oaksford ◽  
Nick Chater
Keyword(s):  
Laboratory Experiments ◽  
Rational Analysis ◽  
The World

AbstractMere facts about how the world is cannot determine how we ought to think or behave. Elqayam & Evans (E&E) argue that this “is-ought fallacy” undercuts the use of rational analysis in explaining how people reason, by ourselves and with others. But this presumed application of the “is-ought” fallacy is itself fallacious. Rational analysis seeks to explain how people do reason, for example in laboratory experiments, not how they ought to reason. Thus, no ought is derived from an is; and rational analysis is unchallenged by E&E's arguments.

scholarly journals Correlation of Myopia with Physical Exercise and Sleep Habits among Suburban Adolescents

2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
Yuan Qu ◽  
Jianfeng Yu ◽  
Wei Xia ◽  
Huijuan Cai
Keyword(s):  
Physical Exercise ◽  
Statistical Significance ◽  
Cross Sectional Study ◽  
Future Research ◽  
Sleep Habits ◽  
Chi Square ◽  
Cross Sectional ◽  
Wake Time ◽  
Potential Association ◽  
Chi Square Test

Purpose. To analyse the correlation of myopia with physical exercise and sleep habits to explore the possible risk or protective factors of juvenile myopia. Methods. This study was a retrospective cross-sectional study. A total of 1831 students aged 11–18 years from five schools in Qingpu completed questionnaires from 2018 to 2019; the students were divided into the nonmyopia group and the myopia group, with students in the myopia group having myopia in at least one eye. Based on the chi-square test, the variables with statistical significance were selected for the logistic regression analysis. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were determined. Results. Myopia was positively associated with older age (OR = 2.216, 95% CI: 1.720–2.855), having a parent with myopia (father: OR = 2.463, 95% CI: 1.900–3.193; mother: OR = 2.853, 95% CI: 2.232–3.646), and a late bedtime during holidays (before 10 pm: p = 0.002; 10 pm-11 pm: OR = 1.516, 95% CI: 1.095–2.100; 11 pm-12 am: OR = 1.966, 95% CI: 1.383–2.795), but negatively correlated with male gender (OR = 0.693, 95% CI: 0.549–0.876), a late daily wake time (OR = 0.782, 95% CI: 0.621–0.985), and having more days per week of outdoor activities during the semester (OR = 0.764, 95% CI: 0.597–0.978). After adjustment for demographic characteristics, myopia was positively associated with a late bedtime during holidays (before 10 pm: p = 0.003; 10 pm-11 pm: OR = 1.570, 95% CI: 1.076–2.289; 11 pm-12 am: OR = 2.173, 95% CI: 1.451–3.253; after 12 am: OR = 1.786, 95% CI: 1.093–2.919), but negatively correlated with a late daily wake time during the semester (OR = 0.761, 95% CI: 0.581–0.997). Conclusion. The association of outdoor exercise with myopia among Chinese suburban adolescents does not seem to be as strong as that of sleep habits. Future research could seek to provide consistent evidence for a potential association between myopia and sleep habits.

scholarly journals Fluoride Variations in Rivers on the Slopes of Mount Meru in Tanzania

2018 ◽  
Vol 2018 ◽  
pp. 1-18 ◽  
Author(s):  
Aldo J. Kitalika ◽  
Revocatus L. Machunda ◽  
Hans C. Komakech ◽  
Karoli N. Njau
Keyword(s):  
Drinking Water ◽  
Water Samples ◽  
Laboratory Experiments ◽  
Fluoride Concentration ◽  
Ion Selective Electrode ◽  
World Health ◽  
Wet Season ◽  
Selective Electrode ◽  
Fluoride Ions ◽  
The World

This study reports the variations of fluoride ions in rivers on the slopes of Mount Meru in the northern part of Tanzania. More than 318 water samples were collected from Temi, Nduruma, Tengeru, and Maji ya Chai Rivers in both wet (mid-March and April) and dry (August) seasons. The samples were analyzed for fluoride levels using Ion Selective Electrode (ISE). The minimum and maximum average fluoride levels in the wet season were 0.24±0.03 mg/l and 65.20±0.03 mg/l, respectively, whereas the average lowest and highest levels in the dry season were 1.02±0.02 mg/l and 69.01±0.03 mg/l, respectively. Tengeru River had the lowest fluoride levels in both seasons, whereas Maji ya Chai recorded the highest fluoride levels in both seasons. The headwater of all rivers with the exception of Maji ya Chai met the World Health Organization’s (WHO) maximum acceptable fluoride levels of 1.50 mg/l and the downstream environment qualified for Tanzania Bureau of Standards (TBS) maximum permissible fluoride concentration in drinking water of 4.00 mg/l. Also, the laboratory experiments showed that fluoride containing rocks exposed to pH above 7.6 display high leaching of F− in solution which gradually increased with the increase in pH, indicating that dissolution of fluoride in water is a function of pH.

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