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Aims/Introduction: Gastrointestinal disturbances and insomnia affect the quality of life of patients with diabetes. However, the relationship between gastrointestinal symptoms and insomnia in patients with diabetes has rarely been analyzed. Thus, aim of this study was to investigate the association between gastrointestinal symptoms and insomnia in patients with type 2 diabetes mellitus. Materials and Methods: This cross‐sectional study of patients with type 2 diabetes was carried out from January 2014 to April 2022 using the database of the KAMOGAWA‐DM cohort study. Patient data were collected using a self‐administered questionnaire, and the Izumo Scale and the Athens Insomnia Scale were used to assess gastrointestinal symptoms and insomnia, respectively. Multivariate logistic regression analysis was carried out to determine the association between gastrointestinal symptoms and insomnia. Results: A total of 175 patients with type 2 diabetes were included in this study. Patients with insomnia had higher Izumo scores than those without insomnia (P < 0.0001). Izumo scale score was significantly associated with insomnia in patients with type 2 diabetes, even after adjustment for age, body mass index, systolic blood pressure, glycated hemoglobin level, neuropathy, insulin therapy and nocturia (odds ratio 1.10, 95% confidence interval [CI] 1.06–1.16). Each gastrointestinal symptom assessed using the Izumo scale was associated with insomnia. The odds ratios of heartburn, stomach pain, lethargy, constipation and diarrhea for insomnia were 1.32 (95% CI 1.13–1.55), 1.38 (95% CI 1.16–1.63), 1.33 (95% CI 1.13–1.56), 1.21 (95% CI 1.08–1.36) and 1.29 (95% CI 1.12–1.47), respectively. Conclusions: Gastrointestinal symptoms are strongly associated with sleep disturbances in patients with type 2 diabetes. [ABSTRACT FROM AUTHOR]

In the current investigation, we modified the high Go, low No-Go Sustained Attention to Response Task (SART) by replacing the single response on Go trials with a dual response to increase response uncertainty. In three experiments, a total of 80 participants completed either the original SART with no response uncertainty regarding the Go stimuli, or versions of the dual response SART in which response probabilities for the two possible responses to the Go stimuli varied from 0.9–0.1, 0.7–0.3, to 0.5–0.5. This resulted in a scale of increasing response uncertainty based on information theory to the Go stimuli. The probability of No-Go withhold stimuli was kept.11 in all experiments. Using the Signal Detection Theory perspective proposed by Bedi et al. (Psychological Research: 1–10, 2022), we predicted that increasing response uncertainty would result in a conservative response bias shift, noted by decreased errors of commission and slower response times to both Go and No-Go stimuli. These predictions were verified. The errors of commission in the SART may not be a measures of conscious awareness per se, but instead indicative of the level of participant trigger happiness—the willingness to respond quickly. [ABSTRACT FROM AUTHOR]

When human monitors are required to detect infrequent signals among noise, they typically exhibit a decline in correct detections over time. Researchers have attributed this vigilance decrement to three alternative mechanisms: shifts in response bias, losses of sensitivity, and attentional lapses. The current study examined the extent to which changes in these mechanisms contributed to the vigilance decrement in an online monitoring task. Participants in two experiments (N = 102, N = 192) completed an online signal detection task, judging whether the separation between two probes each trial exceeded a criterion value. Separation was varied across trials and data were fit with logistic psychometric curves using Bayesian hierarchical parameter estimation. Parameters representing sensitivity, response bias, attentional lapse rate, and guess rate were compared across the first and last 4 minutes of the vigil. Data gave decisive evidence of conservative bias shifts, an increased attentional lapse rate, and a decreased positive guess rate over time on task, but no strong evidence for or against an effect of sensitivity. Sensitivity decrements appear less robust than criterion shifts or attention lapses as causes of the vigilance loss. [ABSTRACT FROM AUTHOR]

This study aimed to examine the effect of time of day (TOD) on the acquisition of basketball game actions from dynamic and static visualizations in physical education students (novice practitioners). Participants were quasi-randomly assigned to three treatments (static pictures, enriched static-pictures, or video). Morning and late-afternoon sessions were conducted, involving study phases and immediate-recall tests [game comprehension (GC) test and game performance (GP) test]. Oral temperature (OT) and mood states (MS) were also measured. Compared to the morning, the results revealed that afternoon resulted in higher OT, higher negative MS (e.g., anxiety and fatigue), and lower positive MS (i.e., vigor) in all experimental conditions. Moreover, the results showed that: (a) GC and GP decreased throughout the day (regardless of treatments), (b) GC and GP were better with enriched static-pictures (with arrows) than with static pictures, at both TOD, and (c) the video resulted in better GC and GP than the two static presentations, at both TOD. This study (a) highlights the morning's superiority in the acquisition of motor skills from dynamic and static visualizations, due to mood disturbances and lower arousal levels, and (b) encourages basketball teachers to use video modeling by experts, particularly in the morning, for explaining tactical skills. [ABSTRACT FROM AUTHOR]

Oral and rectal temperature, urinary excretion of adrenaline and noradrenaline, and heart rate were measured in 28 watchkeepers working a '4-on/8-off' routine, and in 25 dayworkers, on board ships. Readings of oral temperature were taken over 4-hourly periods of up to two weeks; the rectal temperature, urine, and heart rate data were collected on selected days within these periods. Analysis of watchkeepers' temperatures and unconjugated catecholamine excretions showed slight signs of an interactive adaptation to time of day and hours of work, but it was clear that full phase adjustment of the circadian rhythms to shifted hours of work did not occur. The 'split' pattern of sleep imposed by the watch system may be a major factor in preventing complete adaptation of physiological rhythms to shift work in the shipboard situation; this problem could be overcome by devising a system that allows sleep to be taken in a single uninterrupted block each day. [ABSTRACT FROM AUTHOR]

The main objective of the current study was to investigate the effect of time of day on visual and auditory, short-term memory (STM), and long-term memory (LTM) distortions using a hybrid Deese-Roediger-McDermott procedure. In Experiment 1, we used semantically related words, whereas in Experiment 2 – words were characterized by phonological similarity. The results showed a relationship between modality and types of stimuli. In STM, more semantic errors were found in the evening for items presented visually and more errors following auditory presentation for phonologically similar words. In LTM, the analysis revealed a higher rate of semantic distortions in the evening hours for auditorily presented words. For words with phonological similarity, we observed more errors in the evening without the effect of modality. The results support the hypothesis that more reliance is placed on elaborative processing in the evening and more on maintenance processing in the morning; however, this is not modality invariant. [ABSTRACT FROM AUTHOR]

The sustained attention to response task (SART) is a popular measure in the psychology and neuroscience of attention. The underlying psychological cause for errors, in particular errors of commission, in the SART is actively disputed. Some researchers have suggested task-disengagement due to mind-wandering or mindlessness, and others have proposed strategic choices. In this study we explored an alternative perspective based on Signal Detection Theory, in which the high rate of commission errors in the SART reflects simply a shift in response bias (criterion) due to the high prevalence of Go-stimuli. We randomly assigned 406 participants to one of ten Go-stimuli prevalence rates (50%, 64%, 74%, 78%, 82%, 86%, 90%, 94%, 98% and 100%). As Go-stimuli prevalence increased reaction times to both Go and No–Go stimuli decreased, omission errors decreased and commission errors increased. These all were predicted from a hypothesized bias shift, but the findings were not compatible with some alternative theories of SART performance. These findings may have implications for similar tasks. [ABSTRACT FROM AUTHOR]

Previous work has shown that, in many visual search and detection tasks, observers frequently miss rare but important targets, like weapons in bags or abnormalities in radiological images. These prior studies of the low-prevalence effect (LPE) use static stimuli and typically permitted observers to search at will. In contrast, many real-world tasks, like looking for dangerous behavior on the road, only afford observers a brief glimpse of a complex, changing scene before they must make a decision. Can the LPE be a factor in in dynamic, time-limited moments of real driving? To test this, we developed a novel hazard-detection task that preserves much of the perceptual richness and complexity of hazard detection in the real world, while allowing for experimental control over event prevalence. Observers viewed brief video clips of road scenes recorded from dashboard cameras and reported whether they saw a hazardous event. In separate sessions, the prevalence of these events was either high (50% of videos) or low (4%). Under low prevalence, observers missed hazards at more than twice the rate observed in the high-prevalence condition. Follow-up experiments demonstrate that this elevation of miss rate at low prevalence persists when participants were allowed to correct their responses, increases as hazards become increasingly rare (down to 1% prevalence) and is resistant to simple cognitive intervention (participant prebriefing). Together, our results demonstrate that the LPE generalizes to complex perceptual decisions in dynamic natural scenes, such as driving, where observers must monitor and respond to rare hazards. [ABSTRACT FROM AUTHOR]

The operation of naval vessels involves watchkeeping 24 h per day, which is globally carried out by a variety of different watch systems. In this study, the rotating 4:4 and fixed 4:4/6:6 two-section watch systems were compared in terms of sleepiness, fatigue, and stress responses. The data collection took place on a Finnish Defence Forces' (FDF) Navy missile patrol boat with 15 crew members serving as study participants. The data collection periods lasted two separate weeks (7 days, 6 nights) with the different watch systems. The subjective sleepiness of the participants was assessed before and after every watch using the Karolinska Sleepiness Scale (KSS). Stress responses were assessed daily by the recorded levels of salivary alpha-amylase (sAA), cortisol (sCor), immunoglobulin A (sIgA), and dehydroepiandrosterone (sDHEA). The participants' sustained attention, inhibitory control, and working memory were assessed daily by cognitive tests (SART, N-Back). The heart rate variability (HRV) during an orthostatic test was used as an additional daily marker to assess the amount of psychological stress of the participants. In this study, the difference regarding sleepiness and fatigue between the study weeks was most visible in the subjective KSS, which clearly favored the 4:4/6:6 system. The results of sAA and sIgA also suggested that the subjects were psychologically less stressed during the study week with the 4:4/6:6 watch system. Cognitive test results (SART, N-Back) indicated that there were overall no significant differences in the subjects' sustained attention, inhibitory control, or working memory during the study weeks or between the study weeks. The results of the HRV data during the daily orthostatic tests were inconclusive but there was some indication that the subjects were less stressed during the study week with the 4:4/6:6 watch system. In conclusion, the present study indicates that in navy surface operations: working with the fixed 4:4/6:6 watch system causes less sleepiness, fatigue, and psychological stress than working with the rotating 4:4 watch system. The study result is well in line with previous research regarding watch systems. [ABSTRACT FROM AUTHOR]

The submarine working and living environment is an isolated, confined, and extreme (ICE) environment where a continuous onwatch is required to fulfill the tactical objectives. The current study examined whether a physiological and behavioral adjustment to an operational watch standing scheme occurred in terms of hormonal secretion (i.e., melatonin and cortisol) and sleep during a 67-day undersea mission. The crew followed a strict scheme of watch-on blocks at 0:00-06:00 h and at 12:00-18:00 h (group 1, diurnal sleep group) or watch-on blocks at 06:00-12:00 h and 18:00-24:00 h (group 2, nocturnal sleep group). We sampled saliva during the operational blocks over a 24-h period at day 55 of the mission and collected sleep actigraphy data during the entire mission in 10 participants. Sleep showed a biphasic split pattern with significantly unequal distributions of total sleep time (TST) and sleep efficiency (SE) between the two sleeping blocks, i.e., one long and one short sleep bout. Melatonin secretion showed no adjustment at the end of the mission to the watch standing blocks, following an endogenous circadian rhythm independent from the social zeitgebers with indications of a phase shift. Cortisol secretion however matched the biphasic work-sleep shift routine. Human physiology does not fully obey operational needs and there are differences in adjustment between melatonin and cortisol. A watch standing schedule that provides a balance between physiology and operationality still needs to be established. The potential adaptation effects of bright light therapy and melatonin supplementation should be investigated in future research. NEW & NOTEWORTHY The current study has a unique character due to the field context in which the data were collected. Data on long-term submarine missions are scarce and valuable in terms of operational and ecological validity. Moreover, the results are important both from a scientific and operational point of view, showing that human physiology does not fully obey operational needs and that there are differences in adjustment dependent from the type of circadian hormone. [ABSTRACT FROM AUTHOR]

Purpose: To compare physical, psychological, and physiological adaptations between rotating and morning shift health workers using objective and subjective approaches. Methods: Forty nurses [n = 20 morning shift (MS) group; n = 20 rotating shift (RS) group] were evaluated for anthropometry, body composition, and handgrip strength. Quality of life, depression, fatigue, daytime sleepiness, and sleep quality were assessed with SF-36, Zung Self-Rating Depression Scale (SDS), Fatigue Severity Scale (FSS), Epworth Sleepiness Scale (ESS), and Pittsburgh Sleep Quality Index (PSQI), respectively. Physical activity was assessed by the International Physical Activity Questionnaire (IPAQ) and triaxial accelerometers. Sleep-related data were monitored with sleep actigraphy. Salivary melatonin levels were analyzed before/after sleep, and blood lipid profiles were measured the following morning. Results: The RS group had higher mean BMI and total and abdominal fat and scored lower in the SF-36 (p < 0.01). All nurses showed reduced physical activity levels, which, in the RS group, were negatively correlated with FSS (p = 0.033) and SDS scores (p = 0.025). Poor sleep was revealed in 53% of nurses. The RS group had worse sleep quality by PSQI than the MS group (p = 0.045). PSQI scores were inversely related to SF-36 scores and positively correlated with FSS, BMI, waist circumference, and body fat (p < 0.05). Conclusion: RS nurses showed increased body mass and total and abdominal fat along with decreased quality of life and sleep quality compared to MS counterparts. A strong relationship was found between physical, psychological, and physiological domains. Further studies should consider workplace interventions to prevent obesity, promote physical activity, and manage poor sleeping patterns in nurses. [ABSTRACT FROM AUTHOR]

Background: The present research aimed to propose a positive mental health model in relation to occupational stress and coping styles among train drivers of Indian railways. Methods: Sample (N = 300) in the age group of 21-59 years, with 40 years of mean age, and the job experience ranged from 3 to 40 years with a mean of 15 years was undertaken through purposive sampling technique. The sample also had a proper representation of the sociodemographic background. The survey-based research design with an empirical approach was used in the present study. Results: The structural equation model revealed the positive mental health of train drivers negatively associated with the experience of occupational stress. Their flourishing state has supported the positive effect of problem-focused coping and the negative effect of social support. However, this relationship with work stress was absent. Through moderation effect, problem-focused coping style strengthens the inverse association between occupational stress and positive mental health. This effect was equivalent across all living areas and income groups at the model as well as the path levels. Conclusions: This study revealed that train drivers who engaged in problem-focused coping could better handle organizational role stress and benefit from improved mental well-being. Therefore, many failures in the railway caused by human error emphasize the importance of this preventive strategy. [ABSTRACT FROM AUTHOR]

The safety of a ship depends substantially on its bridge watchkeepers, whose alertness and efficiency must be maintained at all hours of the day and night. Fatigue, circadian rhythms, and sleep disruption occasioned by the unusual working hours of these personnel may all affect their performance. A methodology for assessing the magnitude of this problem is proposed. The application of this methodology in a large-scale shipboard study of merchant mariners on extended voyages is then described, and details given of the techniques used to measure sleep and activity, and temporal variations in a range of physiological and psychological parameters. A summary of the data collected in the study is provided as a reference point for the reports on the different aspects of the results that follow in subsequent articles. [ABSTRACT FROM AUTHOR]

Forty students performed on a perceptual discrimination task both before and after a mid-day lunch interval. Half of the students consumed a three-course lunch during the interval, the remaining half abstained from lunch. It was found that the actual ability to discriminate between events was significantly impaired following the consumption of lunch, but did not alter when no food was ingested. The magnitude of the post-lunch dip in discrimination efficiency was significantly greater in the less 'neurotic' and the more 'extraverted' individuals, according to scores on the Eysenck Personality Inventory, and was also significantly though negatively related to the extent of the drop in sublingual temperature that occurred over the lunch interval. It is concluded that operational efficiency and safety may be at risk following lunch. [ABSTRACT FROM AUTHOR]

Rationale and objective: Variation of visual selective attention through the day has been demonstrated in several arenas of human performance, including radiology. It is uncertain whether this variation translates to an identifiable diurnal pattern of error rates for radiology interpretation. The purpose of this study was to attempt to identify particular days of the week and times of the day when radiologists might be most prone to error. Materials and methods: Abdomen/pelvis CT studies containing at least one major error were collected from a 10-year period from the quality assurance (QA) database at our institution. A major error was defined as a missed finding that had altered management in a way potentially detrimental to the patient. The identified studies were categorized by the day of the week and hour of the day that the study was interpreted. Study volume data over this same period was also obtained by day of the week and time of day, so to normalize the data based on case volume. Standard errors of the volume-adjusted error rates were obtained based on the binomial distribution. The null hypothesis of constant error rates over time was tested using a weighted logistic regression model with linear time as predictor. Results: A total of 252 major errors were identified. More errors were made on Monday than on any other day of the week (n = 58). Major error rates increased through the mid to late morning (9 am to 12 pm), and then decreased progressively through the afternoon until 4 pm, when a rise in the error rate was seen. This pattern persisted when error rates were normalized by study volume within each hour. Overall tests of time-constancy of error rates by day and hour were statistically significant (both p-values < 0.001). Conclusion: Our study shows that error rates in abdominal CT do seem to vary with time of day and day of the week. During the workweek, error rates were highest in the late morning and at the close of the workday, and greater on Mondays than other days. [ABSTRACT FROM AUTHOR]

Biological oscillations often cycle at different harmonics of the 24-h circadian rhythms, a phenomenon we coined "Musica Universalis" in 2017. Like the circadian rhythm, the 12-h oscillation is also evolutionarily conserved, robust, and has recently gained new traction in the field of chronobiology. Originally thought to be regulated by the circadian clock and/or environmental cues, recent new evidences support the notion that the majority of 12-h rhythms are regulated by a distinct and cell-autonomous pacemaker that includes the unfolded protein response (UPR) transcription factor spliced form of XBP1 (XBP1s). 12-h cycle of XBP1s level in turn transcriptionally generates robust 12-h rhythms of gene expression enriched in the central dogma information flow (CEDIF) pathway. Given the regulatory and functional separation of the 12-h and circadian clocks, in this review, we will focus our attention on the mammalian 12-h pacemaker, and discuss our current understanding of its prevalence, evolutionary origin, regulation, and functional roles in both physiological and pathological processes. [ABSTRACT FROM AUTHOR]

A distinct 12-hour clock exists in addition to the 24-hour circadian clock to coordinate metabolic and stress rhythms. Here, we show that liver-specific ablation of X-box binding protein 1 (XBP1) disrupts the hepatic 12-hour clock and promotes spontaneous non-alcoholic fatty liver disease (NAFLD). We show that hepatic XBP1 predominantly regulates the 12-hour rhythmicity of gene transcription in the mouse liver and demonstrate that perturbation of the 12-hour clock, but not the core circadian clock, is associated with the onset and progression of this NAFLD phenotype. Mechanistically, we provide evidence that the spliced form of XBP1 (XBP1s) binds to the hepatic 12-hour cistrome to directly regulate the 12-hour clock, with a periodicity paralleling the harmonic activation of the 12-hour oscillatory transcription of many rate-limiting metabolic genes known to have perturbations in human metabolic disease. Functionally, we show that Xbp1 ablation significantly reduces cellular membrane fluidity and impairs lipid homeostasis via rate-limiting metabolic processes in fatty acid monounsaturated and phospholipid remodeling pathways. These findings reveal that genetic disruption of the hepatic 12-hour clock links to the onset and progression of NAFLD development via transcriptional regulator XBP1, and demonstrate a role for XBP1 and the 12-hour clock in the modulation of phospholipid composition and the maintenance of lipid homeostasis. Hepatocyte 12-hour rhythms have a role in cellular stress and metabolic functions. Here, the authors demonstrate disrupting the 12-hour clock through deletion of XBP1 is associated with the development of NAFLD as well as disruption of phospholipid composition and the maintenance of lipid homeostasis. [ABSTRACT FROM AUTHOR]

This study explored developmental differences in the effects of event rate, temporal expectancy, and sensory modality on continuous performance. Children (ages 7–8 years) and college-aged adults completed visual and auditory continuous performance tasks (CPTs) that were equated at an intermediate (20 events/min) rate using the perceptual sensitivity index (d') and then were compared at faster (40 events/min) and slower (10 events/min) rates to determine the influence of event rate on continuous performance of children and adults. To investigate the effects of temporal expectancy, 20% of the critical signals and neutral events occurred early or late relative to the regular rhythm of the task. The findings (a) suggest that event rate influences continuous performance differently for children and adults, (b) highlight the role of temporal expectancy in continuous performance, and (c) reveal differences in the effects of event rate and temporal expectancy on visual and auditory continuous performance. [ABSTRACT FROM AUTHOR]

It is often assumed the quality of life of dayworkers is better than that of shiftworkers. Our findings from United States Navy (USN) sailors (N = 804, 78.4% males) showed dayworkers slept better, were less sleepy, and reported greater vigor and reduced fatigue (Profile of Mood States) than shiftworkers. Nevertheless, ~25% of dayworkers slept <6.5 h/d, ~62% had split sleep, 31% reported excessive daytime sleepiness (EDS), and ~64% were poor sleepers (Pittsburgh Sleep Quality Index). The two groups had similar sleep-related behaviors, rates of insomnia, comorbid EDS/insomnia, and scores on total mood disturbance, tension/anxiety, depression, anger/hostility, and confusion/bewilderment. The findings of our study indicate shipboard sleep-related issues are prevalent among USN sailors. [ABSTRACT FROM AUTHOR]

In the recent times, it has become critical for the shipping companies to manage the diversity of people and gauge the extent to which they experience job resources and exhibit personal resources. The paper analyses if there exists a difference in the job and personal resources across various demographic factors. The comparison of these resources can aid in capitalizing on the human assets by managing diversity in the shipping companies. Analysis of data collected from 351 marine employees revealed significant differences, thus implying the fact that different people have different experiences of their job resources and exhibit different personal resources, despite being at the same job. The present study illuminates the existing theoretical foundations regarding job and personal resources in the shipping industry and this can help practitioners to take robust recruitment and selection decisions. [ABSTRACT FROM AUTHOR]

Important events in the history of driving under the influence of alcohol (DUI) and/or other drugs (DUID) are reviewed covering a period of approximately 100 years. This coincides with major developments in the pharmaceutical industry and the exponential growth in motor transportation worldwide. DUID constitutes an interaction between the driver, the motor-driven vehicle, and one or more psychoactive (mind-altering) substances. In this connection, it is important to differentiate between drugs intended and used for medical purposes (prescription or licit drugs) and recreational drugs of abuse (illicit drugs). All chemicals with a mechanism of action in the central nervous system (brain and spinal cord) are potentially dangerous to use when skilled tasks, such as driving, are performed. The evidence necessary to charge a person with drug-impaired driving has evolved over many years and initially rested on a driver's own admissions and observations made about the driving by police officers or eyewitnesses. Somewhat later, all suspects were examined by a physician, whose task was to ask questions about any recent ingestion of alcohol and/or other drugs and to administer various clinical tests of impairment. By the 1940s-1950s, the driver was asked to provide samples of blood, breath, or urine for toxicological analysis, although the test results served only to verify the type of drug causing impairment of the driver. The current trend in DUID legislation is toward zero-tolerance or concentration per se statutes, which are much more pragmatic, because behavioral evidence of impairment is no longer a lynchpin in the prosecution case. This legal framework puts considerable emphasis on the results of toxicological analysis; therefore, the methods used must be accurate, precise, and fit for forensic purposes. Many traffic delinquents charged with DUI or DUID suffer from a substance use and/or personality disorder, with high recidivism rates. In addition to conventional penalties and sanctions for drug-related traffic crimes, many offenders would probably benefit from a medical intervention, such as counseling, rehabilitation, and treatment for substance use disorder, which often coexists with a mental health problem. [ABSTRACT FROM AUTHOR]

The aim of this work is to establish rapid, simple, precise and economical methods viz., area under curve were developed and validated for estimation of tramadol hydrochloride in pharmaceutical dosage forms. Further, this study is designed to validate the developed methods as per ICH guidelines. The work was carried out to for estimation of Tramadol in bulk pharmaceutical form by utilizing area under curve (AUC) method using UV-Visible Spectrophotometry. For this purpose the wavelength range 200-400 nm was selected. Distilled water was used as a solvent throughout the work. Linearity was observed in concentration range 5-25 µm/ml (r² =0.9992) for the method. The developed method was found to be simple, linear, precise, accurate and sensitive which can be used for routine quality control analysis for spectrophotometric estimation of Active Pharmaceutical Ingredient. [ABSTRACT FROM AUTHOR]

Imbalance of the circadian rhythm leads to pathologies including obesity, neurodegenerative diseases, and even cancer. Acrylamide (ACR) is a chronic neurotoxin which can lead to carcinogenicity, reproduction toxicity, teratogenicity, and neurotoxicity. The aim of this study was to reveal a potential mechanism of ACR-triggered neurotoxicity related to circadian clock in mice brain. For this purpose, 80 3-month-old C57/BL6J mice were randomly divided into two groups (n = 40/group): the control group was fed a standard diet (AIN-93M) with pure water, and the ACR group was fed a standard diet (AIN-93M) with 0.003% ACR in drinking water for 16 weeks. In the current study, ACR treatment induced circadian disorder and suppressed the circadian-related protein expressions in mice brain. Furthermore, ACR diet aggravated the cognitive dysfunction and spatial memory loss at night phase. Consistent with these results, ACR caused cognitive defects in the night period by down-regulating the ERK/cAMP response element-binding protein (CREB)/brain-derived neurotrophic factor (BDNF) signaling pathways and the expression of synaptosomal-related protein SNAP-25 and PSD-95. Moreover, excessive autophagy phenomenon also occurred in mice hippocampus in the night phase under ACR administration. Of note, ACR stimulated the brain inflammatory reaction via affecting the intestinal barrier integrity and increasing the levels of circulating LPS, IL-1β and TNF-α. Above all, the present research discovered that ACR is a potential circadian-depressing compound that influences cognitive function in mice brain. [ABSTRACT FROM AUTHOR]

This study provides novel evidence that expert economic agents' work-related activities are systematically influenced by the time of day. We use archival data derived from time-stamped quarterly earnings conference calls together with linguistic algorithms to measure and track the moods of executives and analysts at different times of the day. The evidence indicates that the tone of conference call discussions deteriorates markedly over the course of the trading day, with both analysts' and executives' moods becoming more negative as the day wears on. Capital market pricing tests reveal that the time-of-day-induced negative tone leads to temporary stock mispricings. Our findings are relevant because the diurnal variations in behavior documented in the context of quarterly earnings calls are likely to extend across other important corporate communication, decision making, and performance situations, leading to potentially significant economic consequences. This paper was accepted by Shiva Rajgopal, accounting. [ABSTRACT FROM AUTHOR]

Background: Seasickness and travel sickness are classic types of motion illness. Modern simulation systems and virtual reality representations can also induce comparable symptoms. Such manifestations can be alleviated or prevented by various measures. Methods: This review is based on pertinent publications retrieved by a PubMed search, with special attention to clinical trials and review articles. Results: Individuals vary in their susceptibility to autonomic symptoms, ranging from fatigue to massive vomiting, induced by passive movement at relatively low frequencies (0.2 to 0.4 Hz) in situations without any visual reference to the horizontal plane. Younger persons and women are considered more susceptible, and twin studies have revealed a genetic component as well. The various types of motion sickness are adequately explained by the intersensory conflict model, incorporating the vestibular, visual, and proprioceptive systems and extended to include consideration of postural instability and asymmetry of the otolith organs. Scopolamine and H1-antihistamines, such as dimenhydrinate and cinnarizine, can be used as pharmacotherapy. The symptoms can also be alleviated by habituation through long exposure or by the diminution of vestibular stimuli. Conclusion: The various types of motion sickness can be treated with general measures to lessen the intersensory conflict, behavioral changes, and drugs. [ABSTRACT FROM AUTHOR]

Background: This study comprehensively reviewed the literature on the impact of shorter versus longer shifts on critical and important outcomes for Emergency Medical Services (EMS) personnel and related shift worker groups.Methods: Six databases (e.g., PubMed/MEDLINE) were searched, including one website. This search was guided by a research question developed by an expert panela prioriand registered with the PROSPERO database of systematic reviews (2016:CRD42016040099). The critical outcomes of interest were patient safety and personnel safety. The important outcomes of interest were personnel performance, acute fatigue, sleep and sleep quality, retention/turnover, long-term health, burnout/stress, and cost to system. Screeners worked independently and full-text articles were assessed for relevance. Data abstracted from the retained literature were categorized as favorable, unfavorable, mixed/inconclusive, or no impact toward the shorter shift duration. This research characterized the evidence as very low, low, moderate, or high quality according to the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology.Results: The searched yieldedn= 21,674 records. Of the 480 full-text articles reviewed, 100 reported comparisons of outcomes of interest by shift duration. We identified 24 different shift duration comparisons, most commonly 8 hours versus 12 hours. No one study reported findings for all 9 outcomes. Two studies reported findings linked to both critical outcomes of patient and personnel safety, 34 reported findings for one of two critical outcomes, and 64 did not report findings for critical outcomes. Fifteen studies were grouped to compare shifts <24 hours versus shifts ≥24 hours. None of the findings for the critical outcomes of patient and personnel safety were categorized as unfavorable toward shorter duration shifts (<24 hours). Nine studies were favorable toward shifts <24 hours for at least one of the 7 important outcomes, while findings from one study were categorized as unfavorable. Evidence quality was low or very low.Conclusions: The quality of existing evidence on the impact of shift duration on fatigue and fatigue-related risks is low or very low. Despite these limitations, this systematic review suggests that for outcomes considered critical or important to EMS personnel, shifts <24 hours in duration are more favorable than shifts ≥24 hours. [ABSTRACT FROM PUBLISHER]

Introduction: Increasing population, the need for services, and industrialization of societies have led to a growing demand for shift work. Shiftwork causes several disorders, and determining the weight of each disorders is important for their prevention and treatment. Therefore, the purpose of the present study was to use Analytic Network Process (ANP) to prioritize and weigh shift work disorders among the personnel of hospitals of Kerman University of Medical Sciences. Methods: This cross-sectional, descriptive-analytical study was conducted in 2017 among 300 shift work personnel of 10 public hospitals affiliated with Kerman University of Medical Sciences. ANP was used to prioritize and weigh shift work disorders. To this end, the criteria, sub-criteria, and alternatives were initially identified. Then, shift work disorders were categorized into 7 general criteria, 20 sub-criteria, and 3 alternatives. After designing the ANP and determining the effect of each criterion on the sub-criteria, the ANP questionnaire was developed and administered among the shift work personnel, who filled it out based on ANP. Super Decisions was subsequently used to weigh and prioritize shift work disorders. Results: The results indicated that shift work disorders among the nurses included sleep disorders (0.297), psychological disorders (0.275), digestive disorders (0.137), personal life disorders (0.122), etc., in that order of weighing. With respect to the support staff, the major shift work disorders involved sleep disorders (0.252), digestive disorders (0.198), personal life disorders (0.168), and psychological disorders (0.164). Considering security personnel, the top four shift work disorders were sleep disorders (0.201), digestive disorders (0.186), psychological disorders (0.174), and personal life disorders (0.145). Conclusion: According to the findings, sleep disorders had the highest weight in the three studied groups. Moreover, the night shift had the most profound effect on shift work disorders among the personnel in the three groups. It was followed by the evening shift. Morning shift had the lowest influence on shift work disorders. Therefore, the schedules should be taken to prevent these complications in the shift workers. It is suggested that work shift complications be included in the periodic examination program and, in case of discovery of any rhythmic disorder in each shift workers, the person should not remain in the shiftwork group for some time. [ABSTRACT FROM AUTHOR]

The circadian time structure (CTS) and its disruption by rotating and nightshift schedules relative to work performance, accident risk, and health/wellbeing have long been areas of occupational medicine research. Yet, there has been little exploration of the relevance of the CTS to setting short-term, time-weighted, and ceiling threshold limit values (TLVs); conducting employee biological monitoring (BM); and establishing normative reference biological exposure indices (BEIs). Numerous publications during the past six decades document the CTS substantially affects the disposition - absorption, distribution, metabolism, and elimination - and effects of medications. Additionally, laboratory animal and human studies verify the tolerance to chemical, biological (contagious), and physical agents can differ extensively according to the circadian time of exposure. Because of slow and usually incomplete CTS adjustment by rotating and permanent nightshift workers, occupational chemical and other contaminant encounters occur during a different circadian stage than for dayshift workers. Thus, the intended protection of some TLVs when working the nightshift compared to dayshift might be insufficient, especially in high-risk settings. The CTS is germane to employee BM in that large-amplitude predictable-in-time 24h variation can occur in the concentration of urine, blood, and saliva of monitored chemical contaminants and their metabolites plus biomarkers indicative of adverse xenobiotic exposure. The concept of biological time-qualified (for rhythms) reference values, currently of interest to clinical laboratory pathology practice, is seemingly applicable to industrial medicine as circadian time and workshift-specific BEIs to improve surveillance of night workers, in particular. Furthermore, BM as serial assessments performed frequently both during and off work, exemplified by employee self-measurement of lung function using a small portable peak expiratory flow meter, can easily identify intolerance before induction of pathology. [ABSTRACT FROM AUTHOR]

Sustained attention is a fundamental cognitive function underlying many activities in daily life including workplace safety, but its natural variation throughout the day is incompletely characterized. To examine time-of-day variation, we collected a large online data set (N = 6,363) with participation throughout the day and around the world on the gradual-onset continuous performance task, a sensitive measure of sustained attention. This allowed us to examine accuracy, attentional stability, and strategy. Results show that both accuracy and attentional stability peak between 9:00 and 11:00 a.m. and progressively decline throughout the day, whereas strategy is more stable. [ABSTRACT FROM AUTHOR]

Despite decades of research on younger adults, little is known about the way in which vigilant attention is affected by healthy aging, and the small body of work that does exist has yielded mixed findings. Prior examinations of aging and vigilant attention have focused almost exclusively on sensory/perceptual tasks despite the fact that many real-world vigilance tasks are semantic in nature and it has been shown that older adults exhibit memory and attention deficits in semantic tasks in other domains. Here, we present the first empirical investigation of vigilant attention to verbal stimuli in healthy normal aging. In Experiment 1 we find that older adults are just as able as younger adults to identify critical targets defined by category membership (both overall and over time). In Experiment 2, we increase the difficulty of the task by changing the target category from one block to the next, but again find no age-group effects in accuracy. Response time data, however, show that older adults respond more slowly and subjective ratings indicate that older adults experience higher workload and arousal compared to their younger counterparts. The practical as well as theoretical implications of these findings are discussed. [ABSTRACT FROM AUTHOR]

The post-lunch dip in cognition is a well-established phenomenon of decreased alertness, memory and vigilance after lunch consumption. Lunch composition reportedly influences the post-lunch dip. Moreover, dieting is associated with cognitive function impairments. The negative effects of dieting have been reversed with nut-supplemented diets. The aims of this study were to (1) evaluate the acute effect of an almond-enriched high-fat lunch or high-carbohydrate lunch on the post-lunch decline in cognitive function, and (2) evaluate the effects of chronic almond consumption as part of an energy-restricted diet on the memory and attention domains of cognitive function. In total, eighty-six overweight and obese adults were randomised to consume either an almond-enriched diet (AED) or a nut-free control diet (NFD) over a 12-week weight loss intervention. Participants were also randomised to receive either an almond-enriched high-fat lunch (A-HFL) (>55 % energy from fat, almonds contributing 70–75 % energy) or a high-carbohydrate lunch (HCL) (>85 % energy from carbohydrates) at the beginning and end of the weight loss intervention. Memory and attention performance indices decreased after lunch consumption (P<0·001). The A-HFL group ameliorated the decline in memory scores by 57·7 % compared with the HCL group (P=0·004). Both lunch groups had similar declines in attention. Moreover, memory and attention performance indices increased after the 12-week intervention period (P<0·05) with no difference between the AED and NFD groups. In conclusion, almond consumption at a midday meal can reduce the post-lunch dip in memory. However, long-term almond consumption may not further improve cognitive function outcomes in a weight loss intervention. [ABSTRACT FROM AUTHOR]

Aims: Why are some healthy male shift workers (SWers) overweight [body mass index (BMI) >25 and <30] if not obese (BMI >30)? Seven risk factors potentially causing overweight and obesity were evaluated, namely (1) age, (2) physical/sports activity, (3) length of exposure to shift work (SW), (4) speed of shift rotation, (5) tolerance to SW, (6) internal desynchronization of circadian rhythms and (8) night eating (nocturnal nibbling). “New” as well as “old” data, acquired from longitudinal and individual time series of 5–56 days recording span, were reanalyzed. The data were analyzed from a set of field studies of 67 SWers and 53 non-shift workers (non-SWers). To estimate the respective weight of these factors, a multiple regression analysis (MRA) was used among other statistical tools. A similar age-related increase in BMI was validated (withp< 0.001) in both SWers and non-SWers. However, in SWers, desynchronization of rhythms increases the effect of age on BMI. Length of exposure to SW, tolerance to SW and speed of rotation do not seem to play a role as risk factors. Major effects are likely to relate to a sedentary lifestyle (lack of regular physical or sport activities) (MRA withp< 0.01), as well as, presumably, to a nocturnal nibbling of carbohydrates, which mimics the night eating syndrome. [ABSTRACT FROM PUBLISHER]

Objective: The aim of the present research was to examine associations between poor driving behaviour (DB), driving when fatigued (DF), risk taking (RT) and road traffic accidents (RTAs). Design: The study involved a cross-sectional online survey of clients of an insurance company. The survey measured DB (speeding, distraction, lapses of attention and aggression), RT and frequency of driving when fatigued (DF, driving late at night, prolonged driving, driving after a demanding working day and driving with a cold). Demographic, lifestyle, job characteristics and psychosocial factors were also measured and used as covariates. Setting: Cardiff, UK. Sample: 3000 clients of an insurance company agreed to participate in the study, and 2856 completed the survey (68% woman, 32% man; mean age: 34 years, range 18-74 years). Main outcome measures: The outcomes were RTAs (requiring medical attention; not requiring medical attention), where the person was the driver. Results: Factor analyses showed that DB, RT and fatigue loaded on independent factors. Logistic regressions showed that poor DB, frequently DF and taking risks predicted medical and non-medical RTAs. These effects were additive and those who reported poor DB, driving when fatigue and taking risks were twice as likely to have an RTA. These effects remained significant when demographic, lifestyle, medical, driving, work and psychosocial factors were covaried. Conclusions: Poor DB, DF and RT predict RTAs. There are now short measuring instruments that can assess these, and driver education programmes must increase awareness of these risk factors. [ABSTRACT FROM AUTHOR]

The extent to which the diurnal fluctuations of different cognitive processes could be affected by sleep loss may be explored to predict performance decrements observed in the real world. Twenty healthy male subjects voluntarily took part in 8 test sessions at 06:00, 10:00, 14:00, and 18:00 h, following either a night with or without sleep in random order. Measurements included oral temperature, simple reaction time, sign cancelation, Go/NoGo, and the Purdue pegboard test. The results indicate that simple reaction time and motor coordination had morning–afternoon variations closely following the rhythms of temperature and vigilance. Inhibitory attention (Go/NoGo) presented no morning–afternoon variations. Sleep deprivation may affect the profiles of cognitive performance depending on the processes solicited. Sustained and inhibitory attention are particularly affected in the morning (after 24 and 28 waking hours), while a complex task (visuo-motor coordination) would be affected after 32 waking hours only. [ABSTRACT FROM AUTHOR]

An emerging literature suggests that experiences of physical warmth contribute to social warmth—the experience of feeling connected to others. Thus, thermoregulatory systems, which help maintain our relatively warm internal body temperatures, may also support feelings of social connection. However, the association between internal body temperature and feelings of connection has not been examined. Furthermore, the origins of the link between physical and social warmth, via learning during early experiences with a caregiver or via innate, co-evolved mechanisms, remain unclear. The current study examined the relationship between oral temperature and feelings of social connection as well as whether early caregiver experiences moderated this relationship. Extending the existing literature, higher oral temperature readings were associated with greater feelings of social connection. Moreover, early caregiver experiences did not moderate this association, suggesting that the physical-social warmth overlap may not be altered by early social experience. Results provide additional support for the link between experiences of physical warmth and social warmth and add to existing theories that highlight social connection as a basic need on its own. [ABSTRACT FROM AUTHOR]

The objective of this study was to identify circadian rhythms in self-monitoring, a component of executive functions. Participants were 10 undergraduate students, age: 18.5 ± 2.68 years, two male and eight female. They were recorded on a 30-h constant routine protocol; rectal temperature was recorded every minute and performance on a tracking task was assessed every 100 min. Self-monitoring indicators were adjustments of responses to random changes of speed and trajectory of a circle moving on the computer screen. Participants showed better accuracy during the afternoon, with decreases in the morning (06:20 and 08:00 h). These variations showed a phase delay of 2:29 ± 2:19 h with respect to the circadian rhythm of body temperature. In conclusion, there are circadian variations in self-monitoring. The decline in this component of executive functions could cause serious accidents among people working or studying during a morning shift, as well as commuting to and from work or school. [ABSTRACT FROM PUBLISHER]

Background: Theoretical models on shift work fall short of describing relevant health-related pathways associated with the broader concept of nonstandard working schedules. Shift work models neither combine relevant working time characteristics applicable to nonstandard schedules nor include the role of rest periods and recovery in the development of health complaints. Therefore, this paper aimed to develop a comprehensive model on nonstandard working schedules to address these shortcomings.Methods: A literature review was conducted using a systematic search and selection process. Two searches were performed: one associating the working time characteristics time-of-day and working time duration with health and one associating recovery after work with health. Data extracted from the models were used to develop a comprehensive model on nonstandard working schedules and health.Results: For models on the working time characteristics, the search strategy yielded 3044 references, of which 26 met the inclusion criteria that contained 22 distinctive models. For models on recovery after work, the search strategy yielded 896 references, of which seven met the inclusion criteria containing seven distinctive models. Of the models on the working time characteristics, three combined time-of-day with working time duration, 18 were on time-of-day (i.e. shift work), and one was on working time duration. The model developed in the paper has a comprehensive approach to working hours and other work-related risk factors and proposes that they should be balanced by positive non-work factors to maintain health. Physiological processes leading to health complaints are circadian disruption, sleep deprivation, and activation that should be counterbalanced by (re-)entrainment, restorative sleep, and recovery, respectively, to maintain health.Conclusions: A comprehensive model on nonstandard working schedules and health was developed. The model proposes that work and non-work as well as their associated physiological processes need to be balanced to maintain good health. The model gives researchers a useful overview over the various risk factors and pathways associated with health that should be considered when studying any form of nonstandard working schedule. [ABSTRACT FROM AUTHOR]

Objectives The aim of this review was to identify which limited wake shift work schedules (LWSW) best promote sleep, alertness, and performance. LWSW are fixed work/rest cycles where the time-at-work does is =8 hours and there is >1 rest period per day, on average, for =2 consecutive days. These schedules are commonly used in safety-critical industries such as transport and maritime industries. Methods Literature was sourced using PubMed, Embase, PsycInfo, Scopus, and Google Scholar databases. We identified 20 independent studies (plus a further 2 overlapping studies), including 5 laboratory and 17 field-based studies focused on maritime watch keepers, ship bridge officers, and long-haul train drivers. The measurement of outcome measures was varied, incorporating subjective and objective measures of sleep: sleep diaries (N=5), actigraphy (N=4), and polysomnography, (N=3); sleepiness: Karolinska Sleepiness Scale (N=5), visual analog scale (VAS) alertness (N=2) and author-derived measures (N=2); and performance: Psychomotor Vigilance Test (PVT) (N=5), Reaction Time or Vigilance tasks (N=4), Vector and Letter Cancellation Test (N=1), and subjective performance (N=2). Results Of the three primary rosters examined (6 hours-on/6 hours-off, 8 hours-on/8 hours-off and 4 hourson/ 8 hours-off), the 4 hours-on/8 hours-off roster was associated with better sleep and lower levels of sleepiness. Individuals working 4 hours-on/8 hours-off rosters averaged 1 hour more sleep per night than those working 6 hours-on/6 hours-off and 1.3 hours more sleep than those working 8 hours-on/8 hours-off (P<0.01). More broadly, findings indicate that LWSW schedules were associated with better sleep and lower sleepines in the case of (i) shorter time-at-work, (ii) more frequent rest breaks, (iii) shifts that start and end at the same clock time every 24 hours, and (iv) work shifts commencing in the daytime (as opposed to night). The findings for performance remain incomplete due to the small number of studies containing a performance measure and the heterogeneity of performance measures within those that did. Conclusion The literature supports the utility of LWSW in industries where individuals sleep at or near the workplace as they facilitate at least some sleep during the biological night and minimize deficits associated with time-on-shift with shorter shifts. Overall, the 4 hour-on/8 hour-off roster best promoted sleep and minimized sleepiness compared to other LWSW schedules. Nevertheless, and considering the safety-critical nature of industries which employ LWSW, the limited literature needs to be greatly expanded with specific focus on the consequences for performance and comparison to mainstream rosters. [ABSTRACT FROM AUTHOR]

Simon Folkard in 1997 introduced the phraseblack timeto draw attention to the fact that the risk of driving accidents (DA) is greater during the night than day in usually diurnally active persons. The 24  h temporal pattern in DA entails circadian rhythms of fatigue and sleep propensity, cognitive and physical performance, and behavior that are controlled, at least in part, by endogenous clocks. This opinion paper extends the concept ofblack timeto reports of excess nighttime accidents and injuries of workers and nocturnal occurrence of certain man-caused catastrophes. We explore the chronobiology of work-relatedblack timeaccidents and injuries taking into account laboratory and field investigations describing, respectively, circadian rhythms in cognitive performance and errors and mistakes by employees in the conduct of routine occupational tasks. Additionally, we present results of studies pertaining to 24  h patterns of both the number and relative risk (number of events per h/number of workers exposed per h) of work-related accidents (WRA) and injuries (WRI) as well as indices of performance and alertness of a self-selected homogenous survivor cohort of French firefighters (FFs) to explore two possible explanations ofblack time, namely, 24  h variation in sleep propensity/drossiness characterized by a nocturnal peak and circadian rhythms in cognitive performance characterized by a nocturnal trough. We propose the 24  h pattern of WRA and WRI, particularly of FFs and other highly skilled self-selected cohorts, is more strongly linked to circadian rhythms of fatigue and sleepiness than cognitive performance. Other possible explanations –suppressed expression of circadian rhythms and/or unmasking of ultradian periodicities in cognitive performance in specific circumstances, e.g., highly stressful work, competitive, or life-threatening settings, are also discussed. [ABSTRACT FROM PUBLISHER]

Purpose: The study investigates if the circadian rhythm of heart rate is apparent during the working periods of day and night shifts in Swiss and Japanese nurses and if it is influenced by work organization. For a better interpretation of the heart rate, the activity profile over these working periods was monitored. Methods: Heart rate and activity profile of 18 Swiss and 24 Japanese nurses were measured during one day and one night shift. The day and the night shift data of each subject were combined, resulting in an approximately 18-h working period. Results: A significant time effect of the mean hourly value of the heart rate was found in Swiss nurses (change in amplitude 7.1 bpm) as well as in Japanese nurses (11.8 bpm). These effects could be modeled with cosine curves for the Swiss and Japanese subjects. For the activity level significant time effects, similar to the ones in heart rate, were found in Swiss nurses (87 % of SD) but not in Japanese nurses (26 % of SD). Conclusions: We found a significant time effect in heart rate similar to the known circadian rhythm under normal sleep-wake conditions while working in the studied shift work schedules. In the Japanese nurses, studied heart rate followed a circadian rhythm independently of the level of physical activity. Therefore, an activity profile following the circadian rhythm, especially a reduced workload from 2 to 4 a.m., is proposed. The proposed activity profile could be reached with an adapted work organization. [ABSTRACT FROM AUTHOR]

Falls are common among the elderly > 65 years of age and can result in both serious trauma and costly medical care. The epidemiology of falls in the elderly typically focuses on identifying contributory exogenous environmental and endogenous age-related physical, cognitive and other health status factors; however, one potentially important variable seldom considered is time of fall. We sought to determine if falls in hospitalized/institutionalized elderly persons exhibit 24 h and other temporal patterns, since knowledge of such could be useful in their prevention. We conducted a systematic review of the published literature to critically appraise and synthesize the methods and findings of previous reports addressing clock-time, day-of-week and month-of-year fall patterns of institutionalized elderly cohorts. Medline, SCOPUS, Ovid SP and Web of Knowledge were systematic assessed, entering search terms of 'accidental fall', 'circadian rhythm', 'biological clocks', 'circadian clocks', 'activity cycles', 'periodicity', and with databases accepting an age limiter, 'age of 65+ years'. Methodological quality was assessed by STROBE and CONSORT checklists, respectively, in observational and clinical studies. Publications were reviewed if meeting inclusion criteria of: (i) being an empirical study, (ii) adopting circadian and/or other period rhythmicity as a fall risk, and (iii) focusing on hospitalized/institutionalized falls in those ≥ 65 years of age; plus exclusion criteria of: (i) cohort < 65 years of age and (ii) reports as dissertations or editorials. The search retrieved 170 publications; however, only nine met all inclusion/exclusion criteria. Typically, past studies disregarded the temporal aspects of fall incidents; the few that did varied in quality, institutional setting, and patient type, i.e. medical diagnoses. Overall, findings suggest a single or double-peak 24 h pattern of fall incidence, with time of greatest incidence seemingly associated with circadian rhythm-dependent differences in the symptom intensity of dominating medical diagnoses (e.g. heart failure versus Alzheimer syndrome) among sample cohorts plus location (e.g. bathroom versus hallway) of occurrence. Future research is urgently required to define temporal patterns in falls and their etiology, e.g. relative to circadian and other rhythms in both the manifestation and intensity of medical conditions and adverse effects of medications according to scheduling, plus staff personnel number and work schedules as it affects patient oversight, and cyclic environmental conditions (e.g. light intensity exposure) to best design preventive measures. [ABSTRACT FROM AUTHOR]

Objective:Previous studies have already shown the possibility of impairment during a hangover phase, after alcohol ingestion, when the blood alcohol concentration has returned to zero. The prevalence of drivers being in a hangover phase, in the driving population, and the relation to impairment relevant for traffic safety has, however, not been previously studied. The aim of this study was to investigate the prevalence and the concentrations of the 2 ethanol metabolites, ethyl glucuronide (EtG) and ethyl sulfate (EtS), in blood, indicating very recent alcohol intake, among apprehended drivers, in which no psychoactive substances, including alcohol, were detected. The aim was also to study these findings in relation to the impairment observed in these drivers. Methods:Blood samples, drawn from suspected drunk or drugged drivers, were analyzed for a broad repertoire of psychoactive substances, with a clinical test for impairment (CTI) being performed at the same time. One hundred and forty-six cases, in which no psychoactive substances were detected and where a valid CTI was performed, were analyzed for EtG and EtS in blood. The prevalence and concentrations were related to the conclusions of the CTIs. Results:EtS and EtG were detected in a total of 19 of the 146 cases (13%). Among the “impaired” drivers, EtG and EtS were detected in 16 cases (18%), whereas among “not impaired” drivers they were detected in 3 cases (5%). There were significantly more detections of EtS (and EtG) among the impaired group of drivers compared to the nonimpaired drivers (P=.030), and the concentrations of both EtG (P=.027) and EtS (P=.026) were significantly higher in the group of impaired drivers compared to the nonimpaired drivers. There was a statistically significant positive correlation between the concentrations of EtG (Spearman's rho = 0.170,P=.041) and EtS (Spearman's rho = 0.189,P=.022) and the degree of impairment. Conclusions:EtG and EtS were prevalent findings in blood collected from the apprehended drivers, testing negative for all psychoactive substances. The higher rates of detections of EtG and EtS in impaired compared to nonimpaired drivers, and also the positive correlation between concentrations of EtG and EtS and the degree of impairment, indicate that hangover symptoms may be relevant for traffic safety. [ABSTRACT FROM AUTHOR]

The pattern of secretion of many hormones, including prolactin, is dependent on the circadian rhythm. Night shift work involves exposure to artificial light at night and sleep deficiency, which in turn can affect prolactin synthesis. The aim of this study was to evaluate a possible association between night shift work characteristics, sleep quality, lifestyle factors and prolactin concentration, using data from a cross-sectional study of nurses and midwives. A cross-sectional study was conducted among 327 nurses and midwives currently working on rotating night shifts, and 330 nurses and midwives working during the day (aged 40-60 years) (388 premenopausal and 269 postmenopausal). Information about night shift work characteristics, lifestyle, reproductive factors, sleep pattern and other covariates was collected through a face-to-face interview, and from a one-week work and sleep diary completed by the subjects. Weight and height were measured. Prolactin concentration was measured in the morning blood sample using the electrochemiluminesence immunoassay method. Associations were analyzed using linear regression models adjusted for important confounders. Analyses were carried out separately in pre- and postmenopausal women. None of the night shift work or sleep characteristics was significantly associated with prolactin concentration. Prolactin concentration was significantly ( p < 0.05) inversely associated with smoking and time of blood sample collection. These results were consistent among both pre- and postmenopausal women. Nulliparity was significantly positively associated with prolactin among premenopausal women, but inversely among postmenopausal. Age was related to prolactin among postmenopausal women only. Our study indicates that rotating night shift work is not associated with prolactin concentration. Smoking, parity, time of blood collection and age among postmenopausal women were significant determinants of prolactin. [ABSTRACT FROM AUTHOR]

Increasing demands on the flexibility of assembly workers has led to numerous times of high exposure rates within one workday. Inflexible processing times in synchronized assembly lines mismatch the individual, circadian variable work capacities of operators. As a result, frequent performance peaks due to limited possibilities for individualization elevate physiological and psychological workloads. This paper's main objective is an individualization of assembly system performance requirements aimed at providing the opportunity to adapt current processing times to individual work capacities for reactively levelling the operators' workload. On the one hand, the authors focus on defining requirements to enable a company to record valid current processing times within a synchronized assembly line. The authors provide a checklist aimed at generating sets of raw data specifying the necessary requirements. This checklist can be applied by the user of the approach. The authors provide an approach of statistical data processing to eliminate non-valid data-sets which do not allow inference on human performance fluctuations. On the other hand, the paper provides an approach for planning synchronized assembly lines taking into consideration human performance fluctuations. Based on defining performance and time characteristics, the authors methodically deduce one exemplary recommendation for the examined synchronized assembly lines quantifying the expected value for production periods. As a result, this combination leads to the possibility of methodically adapting systems' performance requirements to fluctuating operators' work capacity. Moreover, application of the presented approaches within a field study leads to an analysis and evaluation of significant production periods in a German car manufacturer's engine assembly. [ABSTRACT FROM AUTHOR]

Internationalization and technological developments have changed the work organization in developed and developing industrial economies. Information and communication technologies, such as computers and smartphones, are increasingly used, allowing more temporal and spatial flexibility of work. This may lead to an increase in supplemental work, i.e. constant availability or working in addition to contractually agreed work hours. This in turn extends work hours and leads to work hours in evenings and weekends, causing interferences of work hours with biological and social rhythms for sleep, recovery and social interaction. However, empirical findings on the effects of supplemental work and work hours on occupational health are rather scarce. Therefore, the aim of this study was to investigate the association between (1) work-related contacts outside of regular work hours and (2) working in the free time with self-reported work-related health impairments in the fourth and fifth European Working Conditions Surveys (EWCS 2005, EWCS 2010). Out of these cross-sectional, large-scale surveys, data on n = 22 836 and n = 34 399 employed workers were used for weighted logistic regression analyses. About half of the sample reported at least occasional supplemental work. The results showed an increased risk of reporting at least one health problem for employees who had been contacted by their employer (EWCS 2005), or worked in their free time to meet work demands (EWCS 2010) in the last 12 months, compared to those reporting no supplemental work or work-related contacts during free time. These results were controlled for demographic variables, physical and mental work load, worker autonomy, and several work hours characteristics (e.g. hours per week, unusual and variable hours). The risk of reporting health problems was increased by being contacted both sometimes (Odds Ratio [OR] 1.26, 95% Confidence Interval [CI] 1.14-1.39) and often (OR 1.13, 95% CI 1.02-1.25), whereas the frequency of working in the free time showed a clear dose-response effect (sometimes: OR 1.14, 95% CI 1.04-1.24; often: OR 1.60, 95% CI 1.47-1.75), both compared to the category 'never'. The findings, thus, indicate that even a small amount of supplemental work beyond contractually agreed work hours may increase the risk of work-related health impairments. Working in the free time was associated with a substantial risk increase and might be a better indicator for actual work load than being contacted by the employer outside of contractually agreed work hours. Thus, in order to minimize negative health effects, availability requirements for employees outside their regular work hours should be minimized. While these effects definitely need further study, especially regarding a quantification of actual supplemental work and its temporal location, addressing the company culture and using incentives and policies might be options to reduce the amount of supplemental work and maintain the risks of health impairments in the working population at a lower level. [ABSTRACT FROM AUTHOR]