Predictors of interindividual differences in vulnerability to neurobehavioral consequences of chronic partial sleep restriction

Abstract Interindividual differences in the neurobehavioral response to sleep loss are largely unexplained and phenotypic in nature. Numerous factors have been examined as predictors of differential response to sleep loss, but none have yielded a comprehensive view of the phenomenon. The present study examines the impact of baseline factors, habitual sleep–wake patterns, and homeostatic response to sleep loss on accrued deficits in psychomotor vigilance during chronic partial sleep restriction (SR), in a total of 306 healthy adults that participated in one of three independent laboratory studies. Findings indicate no significant impact of personality, academic intelligence, subjective reports of chronotype, sleepiness and fatigue, performance on working memory, and demographic factors such as sex, ethnicity, and body mass index, on neurobehavioral vulnerability to the negative effects of sleep loss. Only superior baseline performance on the psychomotor vigilance test and ability to sustain wakefulness on the maintenance of wakefulness test were associated with relative resilience to decrements in vigilant attention during SR. Interindividual differences in vulnerability to the effects of sleep loss were not accounted for by prior sleep history, habitual sleep patterns outside of the laboratory, baseline sleep architecture, or homeostatic sleep response during chronic partial SR. A recent theoretical model proposed that sleep–wake modulation may be influenced by competing internal and external demands which may promote wakefulness despite homeostatic and circadian signals for sleep under the right circumstances. Further research is warranted to examine the possibility of interindividual differences in the ability to prioritize external demands for wakefulness in the face of mounting pressure to sleep.

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The impact of digitization on economy in the context of the Coronavirus pandemic

SHS Web of Conferences ◽

10.1051/shsconf/20219201018 ◽

2021 ◽

Vol 92 ◽

pp. 01018

Author(s):

Crina Ionescu ◽

Mihaela Iordache ◽

Emilia Țițan

Keyword(s):

Quantitative Research ◽

National Level ◽

Value Added ◽

The Novel ◽

Negative Effects ◽

Global Pandemic ◽

The Face ◽

Novel Coronavirus ◽

The Right ◽

The Impact

Research background: As COVID-19 is posing unprecedented challenges, the governments as well as the individuals have to adapt to the shift towards a new lifestyle. The preventing measures against the spread of the novel coronavirus has important consequences on economy sectors both at global and national level. In this regard, it is the right time to accelerate the development of the digital tools and technologies that can help neutralize or at least mitigate the negative effects of the COVID-19. Purpose of the article: Therefore, the aim of this paper is to evaluate the current situation of digitization, focusing on the main transformations in recent months. Methods: Throughout the paper, there can be distinguished both qualitative and quantitative approach. The methods used include a secondary research from official information and primary quantitative research obtained from a conducted survey that explains the importance and the impact of digitization on economy in the face of a global pandemic. Findings & Value added: The article highlights the impact of digitization on the economy by comparing the findings from Romanian economy with other EU countries. It is noted that in areas where the digitization was more developed or where the adaptation to the new conditions imposed by the crisis generated by COVID-19 has been faster, the impact was significantly lower as well.

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Concordance of multiple methods to define resiliency and vulnerability to sleep loss depends on Psychomotor Vigilance Test metric

SLEEP ◽

10.1093/sleep/zsab249 ◽

2021 ◽

Author(s):

Erika M Yamazaki ◽

Courtney E Casale ◽

Tess E Brieva ◽

Caroline A Antler ◽

Namni Goel

Keyword(s):

Group Performance ◽

Sleep Loss ◽

Vulnerable Groups ◽

Sleep Restriction ◽

Psychomotor Vigilance Test ◽

Performance Change ◽

Vigilance Test ◽

Selection For ◽

Psychomotor Vigilance ◽

Metric Selection

Abstract Study Objectives Sleep restriction (SR) and total sleep deprivation (TSD) reveal well-established individual differences in Psychomotor Vigilance Test (PVT) performance. While prior studies have used different methods to categorize such resiliency/vulnerability, none have systematically investigated whether these methods categorize individuals similarly. Methods 41 adults participated in a 13-day laboratory study consisting of 2 baseline, 5 SR, 4 recovery, and one 36h TSD night. The PVT was administered every 2h during wakefulness. Three approaches (Raw Score [average SR performance], Change from Baseline [average SR minus average baseline performance], and Variance [intraindividual variance of SR performance]), and within each approach, six thresholds (±1 standard deviation and the best/worst performing 12.5%, 20%, 25%, 33%, and 50%) classified Resilient/Vulnerable groups. Kendall’s tau-b correlations examined the concordance of group categorizations of approaches within and between PVT lapses and 1/reaction time (RT). Bias-corrected and accelerated bootstrapped t-tests compared group performance. Results Correlations comparing the approaches ranged from moderate to perfect for lapses and zero to moderate for 1/RT. Defined by all approaches, the Resilient groups had significantly fewer lapses on nearly all study days. Defined by the Raw Score approach only, the Resilient groups had significantly faster 1/RT on all study days. Between-measures comparisons revealed significant correlations between the Raw Score approach for 1/RT and all approaches for lapses. Conclusion The three approaches defining vigilant attention resiliency/vulnerability to sleep loss resulted in groups comprised of similar individuals for PVT lapses but not for 1/RT. Thus, both method and metric selection for defining vigilant attention resiliency/vulnerability to sleep loss is critical.

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122 Different Duration Psychomotor Vigilance Tests Show Robust Stable Relationships Across Sleep Loss That Deteriorate in Recovery

SLEEP ◽

10.1093/sleep/zsab072.121 ◽

2021 ◽

Vol 44 (Supplement_2) ◽

pp. A50-A50

Author(s):

Caroline Antler ◽

Erika Yamazaki ◽

Courtney Casale ◽

Tess Brieva ◽

Namni Goel

Keyword(s):

Sleep Deprivation ◽

Repeated Measures ◽

Response Speed ◽

Sleep Loss ◽

Sleep Restriction ◽

Psychomotor Vigilance Test ◽

Time In Bed ◽

Psychomotor Vigilance ◽

The Relationship ◽

Time Point

Abstract Introduction The Psychomotor Vigilance Test (PVT), a behavioral attention measure widely used to capture sleep loss deficits, is available in 10-minute (PVT10) and 3-minute (PVT3) versions. The PVT3 is a briefer and presumably comparable assessment to the more commonly used PVT10 yet the relationship between the measures from the two versions across specific time points and in recovery after sleep loss has not been investigated. Repeated measures correlation (rmcorr) evaluated within-individual associations between measures on the PVT10 and PVT3 throughout a highly controlled sleep deprivation study. Methods Forty-one healthy adults (ages 21-49; mean±SD, 33.9±8.9y; 18 females) participated in a 13-night experiment consisting of 2 baseline nights (10h-12h time in bed, TIB) followed by 5 sleep restriction (SR1-5) nights (4h TIB), 4 recovery nights (R1-R4; 12h TIB), and 36h total sleep deprivation (TSD). A neurobehavioral test battery, including the PVT10 and PVT3 was completed every 2h during wakefulness. Rmcorr compared PVT10 and PVT3 lapses (reaction time [RT] >355ms [PVT3] or >500ms [PVT10]) and response speed (1/RT) by examining correlations by day (e.g., baseline day 2) and by time point (e.g., 1000h-2000h). Rmcorr ranges were as follows: 0.1-0.3, small; 0.3-0.5, moderate; 0.5-0.7, large; 0.7-0.9, very large. Results All time point correlations (1000h-2000h) were significant (moderate to large for lapses; large to very large for 1/RT). Lapses demonstrated large correlations during R1, moderate correlations during SR1-SR5 and TSD, and small correlations during R2 and R4, and showed no significant correlations during baseline or R3. 1/RT correlations were large for SR1-SR4 and TSD, moderate for SR5 and R1-R4, and small for baseline. Conclusion The various PVT relationships were consistently strong at specific times of day throughout the study. In addition, higher correlations observed for 1/RT relative to lapses and during SR and TSD relative to baseline and recovery suggest that the PVT10 and PVT3 are most similar and best follow performance when most individuals are experiencing behavioral attention deficits during sleep loss. Both measures track SR and TSD performance well, with 1/RT presenting as more comparable between the PVT10 and PVT3. Support (if any) ONR Award N00014-11-1-0361; NIH UL1TR000003; NASA NNX14AN49G and 80NSSC20K0243; NIHR01DK117488

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Residual, differential neurobehavioral deficits linger after multiple recovery nights following chronic sleep restriction or acute total sleep deprivation

SLEEP ◽

10.1093/sleep/zsaa224 ◽

2020 ◽

Author(s):

Erika M Yamazaki ◽

Caroline A Antler ◽

Charlotte R Lasek ◽

Namni Goel

Keyword(s):

Sleep Deprivation ◽

Response Speed ◽

Sleep Loss ◽

Sleep Restriction ◽

Total Sleep Deprivation ◽

Psychomotor Vigilance Test ◽

Recovery Sleep ◽

Time In Bed ◽

Neurobehavioral Deficits ◽

Chronic Sleep

Abstract Study Objectives The amount of recovery sleep needed to fully restore well-established neurobehavioral deficits from sleep loss remains unknown, as does whether the recovery pattern differs across measures after total sleep deprivation (TSD) and chronic sleep restriction (SR). Methods In total, 83 adults received two baseline nights (10–12-hour time in bed [TIB]) followed by five 4-hour TIB SR nights or 36-hour TSD and four recovery nights (R1–R4; 12-hour TIB). Neurobehavioral tests were completed every 2 hours during wakefulness and a Maintenance of Wakefulness Test measured physiological sleepiness. Polysomnography was collected on B2, R1, and R4 nights. Results TSD and SR produced significant deficits in cognitive performance, increases in self-reported sleepiness and fatigue, decreases in vigor, and increases in physiological sleepiness. Neurobehavioral recovery from SR occurred after R1 and was maintained for all measures except Psychomotor Vigilance Test (PVT) lapses and response speed, which failed to completely recover. Neurobehavioral recovery from TSD occurred after R1 and was maintained for all cognitive and self-reported measures, except for vigor. After TSD and SR, R1 recovery sleep was longer and of higher efficiency and better quality than R4 recovery sleep. Conclusions PVT impairments from SR failed to reverse completely; by contrast, vigor did not recover after TSD; all other deficits were reversed after sleep loss. These results suggest that TSD and SR induce sustained, differential biological, physiological, and/or neural changes, which remarkably are not reversed with chronic, long-duration recovery sleep. Our findings have critical implications for the population at large and for military and health professionals.

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Beyond the Pandemic: COVID-19 Pandemic Changed the Face of Life

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18115645 ◽

2021 ◽

Vol 18 (11) ◽

pp. 5645

Author(s):

Shaden A. M. Khalifa ◽

Mahmoud M. Swilam ◽

Aida A. Abd El-Wahed ◽

Ming Du ◽

Haged H. R. El-Seedi ◽

...

Keyword(s):

Human Activities ◽

Social Life ◽

Positive Impact ◽

Mental Wellbeing ◽

Negative Effects ◽

Population Movements ◽

Social Distancing ◽

The Face ◽

The Impact ◽

Positive Impacts

The COVID-19 pandemic is a serious challenge for societies around the globe as entire populations have fallen victim to the infectious spread and have taken up social distancing. In many countries, people have had to self-isolate and to be confined to their homes for several weeks to months to prevent the spread of the virus. Social distancing measures have had both negative and positive impacts on various aspects of economies, lifestyles, education, transportation, food supply, health, social life, and mental wellbeing. On other hands, due to reduced population movements and the decline in human activities, gas emissions decreased and the ozone layer improved; this had a positive impact on Earth’s weather and environment. Overall, the COVID-19 pandemic has negative effects on human activities and positive impacts on nature. This study discusses the impact of the COVID-19 pandemic on different life aspects including the economy, social life, health, education, and the environment.

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116 Behavioral Attention Raw Scores Best Differentiate Cognitive Resilience and Vulnerability to Sleep Loss

SLEEP ◽

10.1093/sleep/zsab072.115 ◽

2021 ◽

Vol 44 (Supplement_2) ◽

pp. A47-A48

Author(s):

Erika Yamazaki ◽

Tess Brieva ◽

Courtney Casale ◽

Caroline Antler ◽

Namni Goel

Keyword(s):

Correlation Coefficients ◽

Response Speed ◽

Sleep Loss ◽

Vulnerable Groups ◽

Average Performance ◽

Psychomotor Vigilance Test ◽

Time In Bed ◽

Attention Performance ◽

Optimal Approach ◽

Psychomotor Vigilance

Abstract Introduction There are substantial, stable individual differences in cognitive performance resulting from sleep restriction (SR) and total sleep deprivation (TSD). The best method for defining cognitive resilience and vulnerability to sleep loss remains an unanswered, yet important question. To investigate this, we compared multiple approaches and cutoff thresholds to define resilience and vulnerability using the 10-minute Psychomotor Vigilance Test (PVT). Methods Forty-one healthy adults (ages 21-49; mean±SD, 33.9±8.9y; 18 females) participated in a 13-night experiment [2 baseline nights (10h-12h time-in-bed, TIB), 5 SR nights (4h TIB), 4 recovery nights (12h TIB), and 36h TSD]. The PVT was administered every 2h during wakefulness. PVT lapses (reaction time [RT]>500 ms) and 1/RT (response speed) were measured. Resilient and vulnerable groups were defined by three approaches: average performance during SR1-5, average performance change from baseline to SR1-5, and variance in performance during SR1-5. Within each approach, resilient/vulnerable groups were defined by +/- 1 standard deviation and by the top and bottom 12.5%, 20%, 25%, 33%, 50%. Bias-corrected and accelerated bootstrapped t-tests compared PVT performance between the resilient and vulnerable groups during baseline and SR1-5. Kendall’s tau correlations compared the ranking of individuals in each group. Results T-tests revealed that the resilient and vulnerable PVT lapses groups, defined by all three approaches, had significantly different mean PVT lapses at all cutoffs. Resilient and vulnerable PVT 1/RT groups, defined by raw scores and by change from baseline, had significantly different mean PVT 1/RT at all cutoffs. However, resilient/vulnerable PVT 1/RT groups defined by variance only differed at the 33% and 50% cutoffs. Notably, raw scores at baseline significantly differed between resilient/vulnerable groups for both PVT measures. Variance vs. raw scores and variance vs. change from baseline had the lowest correlation coefficients for both PVT measures. Conclusion Defining resilient and vulnerable groups by raw scores during SR1-5 produced the clearest differentiation between resilient and vulnerable groups at every cutoff threshold for PVT lapses and response speed. As such, we propose that using PVT raw score is the optimal approach to define resilient and vulnerable groups for behavioral attention performance during sleep loss. Support (if any) ONR Award No.N00014-11-1-0361;NIH UL1TR000003;NASA NNX14AN49G and 80NSSC20K0243;NIH R01DK117488

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The impact of environmental acidification on the microstructure and mechanical integrity of marine invertebrate skeletons

Conservation Physiology ◽

10.1093/conphys/coz062 ◽

2019 ◽

Vol 7 (1) ◽

Cited By ~ 13

Author(s):

Maria Byrne ◽

Susan Fitzer

Keyword(s):

Acid Soil ◽

Negative Effects ◽

Crystal Deposition ◽

Saturation State ◽

Mechanical Integrity ◽

Changing Climate ◽

Run Off ◽

The Face ◽

Coastal Acidification ◽

The Impact

Abstract Ocean acidification (OA), from seawater uptake of anthropogenic CO2, has a suite of negative effects on the ability of marine invertebrates to produce and maintain their skeletons. Increased organism pCO2 causes hypercapnia, an energetically costly physiological stress. OA alters seawater carbonate chemistry, limiting the carbonate available to form the calcium carbonate (CaCO3) minerals used to build skeletons. The reduced saturation state of CaCO3 also causes corrosion of CaCO3 structures. Global change is also accelerating coastal acidification driven by land-run off (e.g. acid soil leachates, tannic acid). Building and maintaining marine biomaterials in the face of changing climate will depend on the balance between calcification and dissolution. Overall, in response to environmental acidification, many calcifiers produce less biomineral and so have smaller body size. Studies of skeleton development in echinoderms and molluscs across life stages show the stunting effect of OA. For corals, linear extension may be maintained, but at the expense of less dense biomineral. Conventional metrics used to quantify growth and calcification need to be augmented by characterisation of the changes to biomineral structure and mechanical integrity caused by environmental acidification. Scanning electron microscopy and microcomputed tomography of corals, tube worms and sea urchins exposed to experimental (laboratory) and natural (vents, coastal run off) acidification show a less dense biomineral with greater porosity and a larger void space. For bivalves, CaCO3 crystal deposition is more chaotic in response to both ocean and coastal acidification. Biomechanics tests reveal that these changes result in weaker, more fragile skeletons, compromising their vital protective roles. Vulnerabilities differ among taxa and depend on acidification level. Climate warming has the potential to ameliorate some of the negative effects of acidification but may also make matters worse. The integrative morphology-ecomechanics approach is key to understanding how marine biominerals will perform in the face of changing climate.

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Continuous action right knife unit with ground interaction analysis

The Russian Automobile and Highway Industry Journal ◽

10.26518/2071-7296-2020-17-4-452-463 ◽

2020 ◽

Vol 17 (4) ◽

pp. 452-463

Author(s):

V. A. Nikolayev ◽

D. I. Troshin

Keyword(s):

Total Energy ◽

Soil Layer ◽

Practical Interest ◽

Longitudinal Force ◽

Energy Costs ◽

Continuous Action ◽

Action Unit ◽

The Face ◽

The Right ◽

The Impact

Introduction. To solve the problem of accelerating the construction of roads, improving their quality, it is advisable to use a continuous action unit to form a underlying layer. The main working bodies of this unit are buckets, which cut off the soil layer from below and on the side. At the same time, the bottom knife cuts off the ground layer from below, the right knife on the side, and the console knife partially cuts the top layer of soil from below for the next bucket. In particular, the analysis of interaction with the soil of the right knife of the continuous action unit is of theoretical and practical interest. To do this, the right knife is divided into elements and analyzed the interaction of these elements with the ground. The consistent impact on the soil of many right knives, within the width of the grip of the unit, is replaced by the impact on the ground of one conventional right knife at a distance necessary for the development of one cubic meter of soil. The forces of interaction of the conventional right knife with the ground are called conditional forces.The method of research. The method for calculating the energy costs during punching the right knife into the ground is shown: on separating the formation of the ground from its body, on overcoming the ground friction on the edge of the blade, on overcoming the ground pressure on the edge of the blade, on accelerating the ground of the blade by means of the axle, on overcoming the ground friction on the shelf, to overcome the ground friction against the outside surface.The total energy costs of interacting with a soil of one cubic meter are derived from the addition of private energy costs. The method of calculating the horizontal longitudinal force needed to move the right knife is given.Results. On the basis of the methodology developed, energy costs are calculated when introducing the right knife into the ground: on separating the soil from its body, on overcoming the friction of the ground on the edge of the blade, on overcoming the pressure of the ground on the face of the blade, on the acceleration of the ground with a fascia blade, on overcoming the ground friction on the face. The total energy costs of the right knife interact with the soil of one cubic meter. The horizontal long-lived force needed to move the right knife has been determined.Conclusion. As a result of the calculations: the energy needed to cut the ground with the right knives, more than 71 J/cube. The horizontal longitudinal force needed to move the right knife is 730 N. To determine the total energy spent on cutting the ground by buckets of the unit to remove the top layer of soil from the underlying layer of the road, it is necessary to analyze the interaction with the soil of other elements of the bucket.

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Right to Health and the Social Determinants of Health in the Face of COVID-19. Tthe Spanish Experience after Austerity Policies

The Age of Human Rights Journal ◽

10.17561/tahrj.v16.6326 ◽

2021 ◽

pp. 220-241

Author(s):

Carlos Lema Añón

Keyword(s):

Health Care ◽

Social Determinants Of Health ◽

Social Determinants ◽

Health Care Systems ◽

Right To Health ◽

Determinants Of Health ◽

The Face ◽

Care Systems ◽

The Right ◽

The Impact

The COVID-19 pandemic has particularly affected Spain in 2020. Although the specific causes and Spain’s response—as well as the aspects to be improved—are yet to be evaluated, many experts agree that this crisis has magnified some of the problems of the Spanish health system, highlighting the problems derived from the cuts in the capacities of the health and public health systems. We assess the current situation from the perspective of the right to health in its twofold dimension: health care and social determinants. For this purpose, we look into the configuration of the right to health in Spain and how the economic crisis and austerity policies affected it. In particular, we consider the impact both on institutional health care systems and in terms of social determinants of health. Finally, we make several proposals for strengthening the right to health.

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0300 The Circadian Timing of Sleep Affects the Rate of Accumulation of Neurobehavioral Impairment Across Days of Sleep Restriction

SLEEP ◽

10.1093/sleep/zsaa056.297 ◽

2020 ◽

Vol 43 (Supplement_1) ◽

pp. A113-A114

Author(s):

M E McCauley ◽

H Van Dongen ◽

S Banks ◽

D F Dinges

Keyword(s):

Young Adults ◽

Dose Response ◽

Sleep Restriction ◽

Circadian Timing ◽

Performance Deficits ◽

Response Effect ◽

Psychomotor Vigilance Test ◽

Dose Response Effect ◽

Psychomotor Vigilance ◽

Nighttime Sleep

Abstract Introduction Chronic restriction of nighttime sleep to less than ~8h/day leads to build-up of neurobehavioral impairment across days. Although it is known that sleep loss effects depend on the circadian timing of sleep, it is not known how the timing of restricted sleep influences the accumulation of neurobehavioral impairment over days. Here we studied the accumulation of impairment across days of restricted sleep placed in the morning or afternoon. Methods N=71 healthy young adults (39% female; ages 21-45y, mean±SD: 27.9±6.6y) completed a 14-day laboratory study. After two baseline days with nighttime sleep (8h TIB: 23:30-07:30), subjects were randomized to 10 consecutive days of A) morning sleep at 4h, 6h, or 8h TIB ending at 11:30 each day (n=18, 8, 8, respectively), or B) afternoon sleep at 4h, 6h, or 8h TIB ending at 19:30 each day (n=13, 17, 7, respectively). Subjects were tested on the 10min psychomotor vigilance test (PVT) every ~2 hours during scheduled wakefulness. Daily averages for PVT lapses (RTs>500ms) observed between 2h and 14h after awakening were analyzed with non-linear mixed-effects regression to investigate differences in the neurobehavioral impairment build-up rate between sleep restriction conditions. Results Afternoon sleep conditions showed a significant sleep dose-response effect (p<0.001), with the fastest accrual of PVT performance deficits across days in the 4h condition, and slow-to-negligible accumulation (p=0.36) of PVT performance deficits in the 8h condition. However, morning sleep resulted in no significant sleep dose-response effect (p=0.96). All 3 morning sleep doses displayed negligible (p≥0.12) accumulation of impairment across days. Conclusion In this sample of young adults, sleep dosages ending in the morning (at 11:30) appear to provide considerable protection against cumulative performance deficits from sleep restricted to 4h-6h/day over 10 days, suggesting that the afternoon circadian promotion of wakefulness can sustain behavioral alertness even over multiple days of repeated sleep restriction. Support NIH grants R01-NR04281 and M01-RR00040

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