Featured Papers from Australasian Chronobiology Society

A topical collection in Clocks & Sleep (ISSN 2624-5175).

Viewed by 29941

Editors


E-Mail Website
Collection Editor
Sleep and Circadian Rhythms Program, School of Psychological Sciences and Turner Institute for Brain and Mental Health, Monash University, 18 Innovation Walk, Clayton Campus, Clayton, VIC 3800, Australia
Interests: light sensitivity; depression; circadian rhythm sleep disorders; sex differences; learning & memory; nonphotic clock input; metabolism
Special Issues, Collections and Topics in MDPI journals

E-Mail Website
Collection Editor
Sleep and Circadian Rhythms Program, School of Psychological Sciences and Turner Institute for Brain and Mental Health, Monash University, 18 Innovation Walk, Clayton Campus, Clayton, VIC 3800, Australia
Interests: light sensitivity; depression; circadian rhythms; chronobiology; mental health; non-visual light responses; psychiatry
Special Issues, Collections and Topics in MDPI journals

Topical Collection Information

Dear Colleagues,

The Australasian Chronobiology Society was founded in 2004, with yearly meetings since, bringing together both basic and clinical researchers across Australia, New Zealand, and the broader region. This includes researchers in both basic and clinical human work, and in a range of model organisms. We are broadly interested in the influence of the circadian clock, and nonimage forming light responses, on behaviour, cognition, sleep and health.

This year, the society met on the 15th of October in Sydney. Our keynote speaker was Professor Paul Zimmet AO, and our international guest was Professor Ken Wright, on the role of the circadian system in metabolic syndrome, and the microbiome, respectively. The day was full of diverse chronobiology and sleep research ranging from ways to best manage shift work maladaptation and jetlag, to understanding home and office lighting, mathematical modelling of biological clocks, and cellular rhythms in the context of diseases such as cancers and HIV.  

With this Special Issue, we invite speakers from the meeting to submit their presented work for publication in Clocks and Sleep, to share work from our society with the broader sleep and chronobiology community.

Assoc. Prof. Sean Cain
Dr. Elise McGlashan
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the collection website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Clocks & Sleep is an international peer-reviewed open access quarterly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 1600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • Chronobiology
  • Circadian rhythms
  • Health
  • Disease
  • Circadian disruption
  • Circadian rhythm sleep disorders
  • Sleep disorders
  • Shift-work

Published Papers (8 papers)

2022

Jump to: 2020, 2019

13 pages, 2471 KiB  
Article
Mild to Moderate Sleep Restriction Does Not Affect the Cortisol Awakening Response in Healthy Adult Males
by Thomas G. Kontou, Gregory D. Roach and Charli Sargent
Clocks & Sleep 2022, 4(4), 722-734; https://doi.org/10.3390/clockssleep4040054 - 25 Nov 2022
Viewed by 1877
Abstract
The cortisol awakening response (CAR) is a distinct rise in cortisol that occurs upon awakening that is thought to contribute to arousal, energy boosting, and anticipation. There is some evidence to suggest that inadequate sleep may alter the CAR, but the relationship between [...] Read more.
The cortisol awakening response (CAR) is a distinct rise in cortisol that occurs upon awakening that is thought to contribute to arousal, energy boosting, and anticipation. There is some evidence to suggest that inadequate sleep may alter the CAR, but the relationship between sleep duration and CAR has not been systematically examined. Healthy males (n = 111; age: 23.0 ± 3.6 yrs) spent 10 consecutive days/nights in a sleep laboratory. After a baseline night (9 h time in bed), participants spent either 5 h (n = 19), 6 h (n = 23), 7 h (n = 16), 8 h (n = 27), or 9 h (n = 26) in bed for seven nights, followed by a 9 h recovery sleep. The saliva samples for cortisol assay were collected at 08:00 h, 08:30 h and 08:45 h at baseline, on experimental days 2 and 5 and on the recovery day. The primary dependent variables were the cortisol concentration at awakening (08:00 h) and the cortisol area under the curve (AUC). There was no effect of time in bed on either the cortisol concentration at awakening or cortisol AUC. In all the time in bed conditions, the cortisol AUC tended to be higher at baseline and lower on experimental day 5. Five consecutive nights of mild to moderate sleep restriction does not appear to affect the CAR in healthy male adults. Full article
Show Figures

Figure 1

2020

Jump to: 2022, 2019

10 pages, 936 KiB  
Article
Accuracy of the GENEActiv Device for Measuring Light Exposure in Sleep and Circadian Research
by Julia E. Stone, Elise M. McGlashan, Elise R. Facer-Childs, Sean W. Cain and Andrew J. K. Phillips
Clocks & Sleep 2020, 2(2), 143-152; https://doi.org/10.3390/clockssleep2020012 - 12 Apr 2020
Cited by 14 | Viewed by 4272
Abstract
Light is a variable of key interest in circadian rhythms research, commonly measured using wrist-worn sensors. The GENEActiv Original is a cost-effective and practical option for assessing light in ambulatory settings. With increasing research on health and well-being incorporating sleep and circadian factors, [...] Read more.
Light is a variable of key interest in circadian rhythms research, commonly measured using wrist-worn sensors. The GENEActiv Original is a cost-effective and practical option for assessing light in ambulatory settings. With increasing research on health and well-being incorporating sleep and circadian factors, the validity of wearable devices for assessing light environments needs to be evaluated. In this study, we tested the accuracy of the GENEActiv Original devices (n = 10) for recording light under a range of ecologically relevant lighting conditions, including LED, fluorescent, infrared, and outdoor lighting. The GENEActiv output had a strong linear relationship with photopic illuminance. However, the devices consistently under-reported photopic illuminance, especially below 100 lux. Accuracy below 100 lux depended on the light source, with lower accuracy and higher variability under fluorescent lighting. The device’s accuracy was also tested using light sources of varying spectral composition, which indicated that the device tends to under-report photopic illuminance for green light sources and over-report for red light sources. Furthermore, measures of photopic illuminance were impacted by infrared light exposure. We conclude that the GENEActiv Original is suitable for mapping light patterns within an individual context, and can reasonably differentiate indoor vs. outdoor lighting, though the accuracy is variable at low light conditions. Given the human circadian system’s high sensitivity to light levels below 100 lux, if using the GENEActiv Original, we recommend also collecting light source data to better understand the impact on the circadian system, especially where participants spend prolonged periods in dim lighting. Full article
Show Figures

Figure 1

23 pages, 634 KiB  
Article
The Association between Sleep Duration and Quality with Readmissions: An Exploratory Pilot-Study among Cardiology Inpatients
by Clementine Labrosciano, Rosanna Tavella, Amy Reynolds, Tracy Air, John F. Beltrame, Isuru Ranasinghe and Robert J. T. Adams
Clocks & Sleep 2020, 2(2), 120-142; https://doi.org/10.3390/clockssleep2020011 - 2 Apr 2020
Cited by 4 | Viewed by 2767
Abstract
Background: Readmissions within 30 days of discharge are prominent among patients with cardiovascular disease. Post hospital syndrome hypothesizes that sleep disturbance during the index admission contributes to an acquired transient vulnerability, leading to increased risk of readmission. This study evaluated the association of [...] Read more.
Background: Readmissions within 30 days of discharge are prominent among patients with cardiovascular disease. Post hospital syndrome hypothesizes that sleep disturbance during the index admission contributes to an acquired transient vulnerability, leading to increased risk of readmission. This study evaluated the association of in-hospital sleep (a) duration and (b) quality with 30-day all-cause unplanned readmission. Methods: This prospective observational cohort study included patients admitted to the coronary care unit of a South Australian hospital between 2016–2018. Study participants were invited to wear an ActiGraph GT3X+ for the duration of their admission and for two weeks post-discharge. Validated sleep and quality of life questionnaires, including the Pittsburgh Sleep Quality Index (PSQI), were administered. Readmission status and questionnaires were assessed at 30 days post-discharge via patient telephone interview and a review of hospital records. Results: The final cohort consisted of 75 patients (readmitted: n = 15, non-readmitted: n = 60), of which 72% were male with a mean age 66.9 ± 13.1 years. Total sleep time (TST), both in hospital (6.9 ± 1.3 vs. 6.8 ± 2.9 h, p = 0.96) and post-discharge (7.4 ± 1.3 h vs. 8.9 ± 12.6 h, p = 0.76), was similar in all patients. Patient’s perception of sleep, reflected by PSQI scores, was poorer in readmitted patients (9.13 ± 3.6 vs. 6.4 ± 4.1, p = 0.02). Conclusions: Although an association between total sleep time and 30-day readmission was not found, patients who reported poorer sleep quality were more likely to be readmitted within 30 days. This study also highlighted the importance of improving sleep, both in and out of the hospital, to improve the outcomes of cardiology inpatients. Full article
Show Figures

Figure 1

21 pages, 1885 KiB  
Review
Global Research Output on Sleep Research in Athletes from 1966 to 2019: A Bibliometric Analysis
by Michele Lastella, Aamir Raoof Memon and Grace E. Vincent
Clocks & Sleep 2020, 2(2), 99-119; https://doi.org/10.3390/clockssleep2020010 - 30 Mar 2020
Cited by 24 | Viewed by 4991
Abstract
This study examined sleep research in athletes published between 1966 and 2019, through a bibliometric analysis of research output in the Scopus database. Following a robust assessment of titles, the bibliometric indicators of productivity for studies included in the final analysis were: Distribution [...] Read more.
This study examined sleep research in athletes published between 1966 and 2019, through a bibliometric analysis of research output in the Scopus database. Following a robust assessment of titles, the bibliometric indicators of productivity for studies included in the final analysis were: Distribution of publications and citations (excluding self-citations), top ten active journals, countries, institutions and authors, single- and multi-country collaboration, and 25 top-cited papers. Out of the 1015 papers, 313 were included in the final analysis. The majority of the papers were research articles (n = 259; 82.8%) and published in English (n = 295; 94.3%). From 2011, there was a dramatic increase in papers published (n = 257; 82.1%) and citations (n = 3538; 91.0%). The number of collaborations increased after 2001, with papers published through international (n = 81; 25.9%) and national (n = 192; 61.3%) collaboration. Australia was the most prolific country in terms of number of publications (n = 97; 31.0%), and citations (n = 1529; 15.8%). In conclusion, after the beginning of the twenty-first century, the scientific production on sleep research in athletes has seen significant growth in publication and citation output. Future research should focus on interventions to improve sleep in athletes. Full article
Show Figures

Figure 1

13 pages, 277 KiB  
Article
Comparing the Effects of FIFO/DIDO Workers Being Home versus Away on Sleep and Loneliness for Partners of Australian Mining Workers
by Kerrie-ann I. Wilson, Sally A. Ferguson, Amanda Rebar, Kristie-Lee Alfrey and Grace E. Vincent
Clocks & Sleep 2020, 2(1), 86-98; https://doi.org/10.3390/clockssleep2010009 - 6 Mar 2020
Cited by 6 | Viewed by 3848
Abstract
Fly in Fly out/Drive in Drive out (FIFO/DIDO) is a prevalent work arrangement in the Australian mining industry and has been associated with adverse outcomes such as psychological stress, sleep disturbances, fatigue, and work/life interference. FIFO/DIDO work arrangements have the potential to not [...] Read more.
Fly in Fly out/Drive in Drive out (FIFO/DIDO) is a prevalent work arrangement in the Australian mining industry and has been associated with adverse outcomes such as psychological stress, sleep disturbances, fatigue, and work/life interference. FIFO/DIDO work arrangements have the potential to not only impact the FIFO/DIDO worker, but also the partner of the FIFO/DIDO worker. However, there is sparse empirical evidence on the impact of FIFO/DIDO work arrangements on partners’ sleep and subsequent performance. Therefore, the primary aim of this study was to describe and compare partners’ sleep quality, sleep duration, sleepiness, and loneliness when the FIFO/DIDO workers were at home (off-shift) and away (on-shift). A secondary aim of this study was to examine whether differences in partners’ sleep quality and sleep duration as a result of FIFO/DIDO worker’s absence could be partially explained through the presence of dependents in the home, relationship duration, chronotype, duration in a FIFO/DIDO role, and loneliness. Self-reported questionnaires were completed by 195 female and 4 male participants, mostly aged between 18 and 44 years and who had been in a relationship with a FIFO/DIDO mining worker for more than five years. Of note, most participants subjectively reported poor sleep quality, insufficient sleep duration, excessive sleepiness, and moderate to extreme loneliness compared to the general population regardless of whether the FIFO/DIDO workers were at home or away. Compared to when the FIFO/DIDO workers were at home, partners experienced reduced sleep quality and increased loneliness when the FIFO/DIDO workers were away. Secondary analyses revealed that loneliness may partially underpin the negative effect that FIFO/DIDO workers’ absence has on sleep quality. Further research is needed to understand the factors that contribute to poor sleep quality, insufficient sleep duration, excessive sleepiness, and loneliness of FIFO/DIDO partners to inform appropriate strategies to support FIFO/DIDO partners’ health and wellbeing not only in the mining population, but other industries that incorporate similar FIFO/DIDO work arrangements (e.g., emergency services, offshore drilling, and transport). Full article
13 pages, 927 KiB  
Article
Impacts of Australian Firefighters’ On-Call Work Arrangements on the Sleep of Partners
by Grace E. Vincent, Simone Karan, Jessica Paterson, Amy C. Reynolds, Michelle Dominiak and Sally A. Ferguson
Clocks & Sleep 2020, 2(1), 39-51; https://doi.org/10.3390/clockssleep2010005 - 30 Jan 2020
Cited by 7 | Viewed by 3426
Abstract
On-call work arrangements are commonly utilised in the emergency services sector and are consistency associated with inadequate sleep. Despite sleep being a common shared behaviour, studies are yet to assess the impact of on-call work on the sleep of co-sleeping partners. This study [...] Read more.
On-call work arrangements are commonly utilised in the emergency services sector and are consistency associated with inadequate sleep. Despite sleep being a common shared behaviour, studies are yet to assess the impact of on-call work on the sleep of co-sleeping partners. This study aimed to investigate whether frequent 24/7 on-call work impacted the sleep and relationship happiness of firefighters’ partners. Two key research questions were investigated: (1) Does the frequency of calls impact sleep and relationship happiness? and, (2) Does the (a) sleep quantity and (b) sleep quality of partners impact perceived relationship happiness? A cross-sectional study was conducted using an online questionnaire completed by partners of on-call workers (n = 66; 93% female). The questionnaire included items on (i) sleep quantity and quality, (ii) on-call sleep disturbances and, (iii) relationship happiness. Responses were analysed using logistic regression models. Higher overnight call frequency was associated with greater self-reported levels of inadequate sleep (<7 h per night; p = 0.024). Support for continuance of a firefighter’s role was less likely if the partner reported they regularly had trouble falling asleep within 30 min (p < 0.001). There were no other significant relationships between the frequency of calls or other sleep quantity or quality variables and relationship happiness. This study provides important first insights into how firefighters’ on-call work arrangements impact partners’ sleep. Future research is needed across periods of high and low call demand, using objective measures of sleep to further define the impacts of on-call work on partners’ sleep. Full article
Show Figures

Figure 1

2019

Jump to: 2022, 2020

12 pages, 279 KiB  
Article
Sleep Problems in School Aged Children: A Common Process across Internalising and Externalising Behaviours?
by Danielle M. Bayes and Ben Bullock
Clocks & Sleep 2020, 2(1), 7-18; https://doi.org/10.3390/clockssleep2010002 - 20 Dec 2019
Cited by 6 | Viewed by 3792
Abstract
Sleep problems are common in childhood and impact cognitive, psychological and physical wellbeing. The current study investigated the association between sleep problems and internalising and externalising behaviour in 114 school-aged children (5–12 years) from four primary schools in Melbourne, Australia. Data were collected [...] Read more.
Sleep problems are common in childhood and impact cognitive, psychological and physical wellbeing. The current study investigated the association between sleep problems and internalising and externalising behaviour in 114 school-aged children (5–12 years) from four primary schools in Melbourne, Australia. Data were collected using the Sleep Disorder Inventory for Students to measure sleep and the Conners Behavior Rating Scale to assess behaviour, both by parent report. Hierarchical regression analysis, controlling for socioeconomic status and age, identified moderate associations between sleep problems and emotional distress, aggressive behaviour and hyperactivity/impulsivity. Findings suggest screening for sleep problems in children presenting clinically with behavioural issues is a potentially important clinical practice. Additionally, results support the elaboration of transdiagnostic theory, whereby sleep problems are a common process in both internalising and externalising behaviour in children. Full article
12 pages, 1447 KiB  
Review
The Development and Decay of the Circadian Clock in Drosophila melanogaster
by Jia Zhao, Guy Warman and James Cheeseman
Clocks & Sleep 2019, 1(4), 489-500; https://doi.org/10.3390/clockssleep1040037 - 19 Nov 2019
Cited by 2 | Viewed by 3588
Abstract
The way in which the circadian clock mechanism develops and decays throughout life is interesting for a number of reasons and may give us insight into the process of aging itself. The Drosophila model has been proven invaluable for the study of the [...] Read more.
The way in which the circadian clock mechanism develops and decays throughout life is interesting for a number of reasons and may give us insight into the process of aging itself. The Drosophila model has been proven invaluable for the study of the circadian clock and development and aging. Here we review the evidence for how the Drosophila clock develops and changes throughout life, and present a new conceptual model based on the results of our recent work. Firefly luciferase lines faithfully report the output of known clock genes at the central clock level in the brain and peripherally throughout the whole body. Our results show that the clock is functioning in embryogenesis far earlier than previously thought. This central clock in the fly remains robust throughout the life of the animal and only degrades immediately prior to death. However, at the peripheral (non-central oscillator level) the clock shows weakened output as the animal ages, suggesting the possibility of the breakdown in the cohesion of the circadian network. Full article
Show Figures

Figure 1

Back to TopTop