Consecutive Nights Research Articles

Habitual Sleep Duration and Sleep Effciency Do Not Mediate the Relationship Between Race and Nocturnal Blood Pressure Dipping in Young Black and White Women

Blunted nocturnal blood pressure (BP) dipping, defined as less than 10% reduction in BP during sleep as compared to wake, independently predicts cardiovascular disease. Short and disturbed sleep associate with less nocturnal BP dipping in young adults, and Black women (BLW) demonstrate less nocturnal BP dipping and poorer sleep health compared to White women (WHW) as early as young adulthood. However, not known is if habitual, objectively estimated sleep metrics mediate the relationship between race and BP dipping in young women. Thus, this study sought to evaluate the mediating effect of objectively estimated habitual sleep duration and sleep effciency on the relationship between race and nocturnal BP dipping in apparently healthy, young BLW and WHW. We hypothesized that BLW would have lower nocturnal systolic and diastolic BP dipping than WHW, but that the relationship between race and nocturnal BP dipping would be at least partly mediated by sleep duration and sleep effciency. Participants were 18-29 years, female, normotensive, nonobese, without evidence of clinical sleep disorders, and self-identified their race as Black or White. Systolic and diastolic BP dipping were each derived from 24-hour ambulatory BP monitoring by subtracting mean asleep BP from mean awake BP, divided by mean awake BP, *100. Sleep duration (total sleep time between sleep onset and offset) and sleep effciency (total sleep time divided by total time in bed dedicated to sleep, *100) were measured via wrist actigraphy for 14 consecutive nights, and means were generated. Race differences in BP dipping and habitual sleep metrics were assessed via independent-samples t-tests. The standard mediation model as proposed by Baron and Kenney (1986) was used to assess the mediating effect of habitual sleep duration and sleep effciency on the relationship between race and systolic and diastolic BP dipping. Participants included 20 BLW (22±3 years) and 17 WHW (25±3 years). Systolic BP dipping (BLW: 9.5±5.9%, WHW: 13.9±5.1%, p=0.02) and diastolic BP dipping (BLW: 16.3±7.3%, WHW: 21.9±5.5%, p=0.01) were lower among BLW. Sleep duration was not different between races (BLW: 6.7±0.5 hrs, WHW: 7.0±0.7 hrs, p=0.14), though sleep effciency was lower among BLW (BLW: 81.6±4.4%, WHW: 86.0±3.1%, p<0.01). In contrast to our hypothesis, neither habitual sleep duration nor sleep effciency significantly mediated the relationship between race and BP dipping (all indirect effects p>0.38). Habitual sleep metrics did not explain race differences in nocturnal BP dipping between young BLW and WHW; thus, future work should consider other physiological, social, or environmental determinants of BP dipping in young BLW. University of Delaware Research Foundation — Strategic Initiative Grant (MAW/FP) and AHA Award #831488 (EH). This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Polysomnographic parameters associated with cognitive function in patients with major depression and insomnia.

To examine whether objective sleep parameters are associated with cognitive function (CF) in patients with major depressive disorder (MDD) with chronic insomnia (CI) and whether the severity of these disorders is related to CF. Thirty patients with MDD with CI attending a tertiary care institution underwent two consecutive nights of polysomnographic (PSG) recording and a battery of neuropsychological tests, which included episodic memory, sustained attention, working memory, and executive function. The severity of MDD and CI was assessed by clinical scales. We examined the relationship between PSG parameters and CF, as well as whether the severity of the disorders is related to CF. Linear regression analysis revealed that total sleep time (TST) was positively associated with higher learning and recall of episodic memory, as well as better attention. Slow-wave sleep (SWS) showed a positive association with better working memory. Furthermore, wake after sleep onset (WASO) was negatively associated with episodic memory and lower attention. No significant relationships were found between the severity of MDD or CI with CF. Both sleep duration and depth are positively associated with several aspects of CF in patients with MDD with CI. Conversely, a lack of sleep maintenance is negatively related to CF in these patients. These findings could help identify modifiable therapeutic targets to reduce CF impairment.

COMPARISON OF ABUNDANCE OF RODENTS IN IMMATURE AND MATURE OIL PALM PLANTATIONS IN LAHAD DATU, SABAH

Regardless of palm age, rodents have been the main concern for oil palm planters. The present study examined the abundance of rodents in immature (1-3-year-old) and mature (18-20-year-old) oil palm plantations (FGVAS Sahabat 17) in Lahad Datu, Sabah. Over a period of 30 months, 150 cage traps were set in a 300-palm area for four consecutive nights each month for immature and mature palms, respectively. During the study, four rodent species, Callosciurus notatus, Rattus exulans, Rattus rattus diardii, and Maxomys whiteheadi were captured. In immature oil palm, R. exulans (53.59%) was the highest number recorded, and R. r. diardii (88.56%) was the highest number in mature oil palm. The total number of rats varied between immature and mature oil palms [t (54) = 7.392, p = 0.0001]. The ratio of the number of rodents captured in immature and mature oil palms was 4:1. There was a significant difference in the abundance of rats in immature and mature oil palms between the wet (U = 25.50, p = < 0.0003) and dry seasons (U = 12.50, p = < 0.001). This study identified the abundance of rodent species in immature and mature oil palm plantations as a baseline for rodent pest management. Keywords: Oil palm, rodent species, wet season, dry season, Lahad Datu.

Effect of dynamic binaural beats on sleep quality: a proof-of-concept study with questionnaire and biosignals.

Binaural beat (BB) has been investigated as a potential modality to enhance sleep quality. In this study, we introduce a new form of BB, referred to as dynamic BB (DBB), which incorporates dynamically changing carrier frequency differences between the left and right ears. Specifically, the carrier frequency of the right ear varied between 100 and 103 Hz over a period, while the left ear remained fixed at 100 Hz, yielding a frequency difference range of 0 to 3 Hz. The objective of this study was to examine the effect of DBB on sleep quality. Ten healthy participants were included in a cross-over design, where they experienced both DBB and a SHAM (absence of sound) condition across two consecutive nights, with polysomnography evaluation. DBB was administrated during pre-sleep initiation, sleep onset, and transition from rapid eye movement (REM) to non-REM stage. DBB significantly reduced sleep latency compared to the SHAM condition. Electrocardiogram analysis revealed that exposure to DBB led to diminished heart rate variability during the pre-sleep initiation and sleep onset periods, accompanied by a decrease in low-frequency power of heart rate during the sleep onset period. DBB might be effective in improving sleep quality, suggesting its possible application in insomnia treatments.

An Alternative In-Home Protocol to Diagnose and Treat Obstructive Sleep Apnea

Abstract Objective Obstructive sleep apnea (OSA) is a major public health problem of pandemic proportions. In-laboratory OSA diagnosis and continuous positive airway pressure (CPAP) titration are insufficient, considering the number of patients affected. Finding alternative ways to diagnose and treat OSA is mandatory, especially in this era of the coronavirus disease 2019 (COVID-19) pandemic. The present study aims to describe an alternative in-home protocol to diagnose and treat OSA. Materials and Methods We enrolled consecutive patients aged ≥ 18 years with moderate/severe OSA, who underwent in-home type-III polysomnography and home-based titration with automatic CPAP, coupled with an oximetry sensor for 3 consecutive nights. Patients were remotely monitored for 90 days to evaluate CPAP compliance and the use of an engagement tool was encouraged. Results We included 86 participants. The median time until the diagnosis was of one day. The mean time from the baseline visit until the acquisition and initiation of the CPAP therapy was of 33 (range: 17 to 52) days. Telemonitoring ensured good compliance in the first 30 (79.2%), 60 (76.3%) and 90 (74.3%) days, with an average daily use of 6.2 ± 1.4 h, 6.0 ± 1.4 h, and 6.0 ± 1.3 h respectively. About 1/3 of the patients used the engagement tool, and CPAP compliance was significantly higher among these patients compared with those who did not used the tool: 89.9% versus 73.5% (p < 0.002), 87.9% versus 70% (p < 0.003), and 86.6% versus 67.6% (p < 0.001) at 30, 60, and 90 days respectively. Conclusion We demonstrated that an alternative in-home protocol to diagnose and treat OSA is effective, ensuring good CPAP compliance after 90 days. Telemonitoring and engagement tools could be strategies to improve CPAP compliance.

Soft-state optical spectroscopy of the black hole MAXI J1305-704

The X-ray dipper MAXI J1305-704 is a dynamically confirmed black hole (BH) X-ray binary discovered a decade ago. While its only outburst has been studied in detail in X-rays, follow-up at other wavelengths has been scarce. We report here the results from an optical spectroscopy campaign across the outburst of MAXI J1305-704. We analysed two epochs of data obtained by the Magellan Clay Telescope during two consecutive nights, when the source was in a soft X-ray spectral state. We identified typical emission lines from outbursting low-mass X-ray binaries, such as the hydrogen Balmer series, He II 4686 Å and the Bowen blend. We focused our analysis on the prominent Hα line, which exhibits asymmetric emission and variable absorption components. We applied both traditional analytical methods and machine-learning techniques in order to explore the association of the absorption features with outflowing phenomena, and we conclude that they are best explained by broad absorption. This result is consistent with reports from other outbursting BHs, where optical outflows have predominantly been observed in the hard state. Further observations at different X-ray states are key to properly test whether this behaviour is universal and to determine the implications for the disc wind physics.

Male mating season range expansion results from an increase in scale of daily movements for a polygynous-promiscuous bird.

Males of species with promiscuous mating systems are commonly observed to use larger ranges during the mating season relative to non-mating seasons, which is often attributed to a change in movements related to reproductive activities. However, few studies link seasonal range sizes to variation in daily space use patterns to provide insight into the behavioral mechanisms underlying mating season range expansion. We studied 20 GPS-tagged male wild turkeys (Meleagris gallopavo), a large upland gamebird, during the mating and summer non-mating seasons to test the hypothesis that larger mating season ranges resulted from male wild turkeys expanding the scale of daily movement activities to locate and court females. We delineated mating and non-mating seasons based on intensity of gobbling, a vocalization tied to courtship behavior, recorded by autonomous recording units distributed across the study area. Mating season ranges were significantly larger than non-mating season ranges. Daily ranges were larger in the mating season, as were distances between roost sites used on consecutive nights. Variance in daily range size was greater in the mating season, but low temporal autocorrelation suggested considerable daily variability in both seasons. We found no evidence that male wild turkeys changed how they distributed daily movements within seasonal ranges, or differences in habitat use, suggesting larger mating season ranges result from male wild turkeys increasing the scale of their daily movements, rather than a systematic shift to a nomadic movement strategy. Likely, the distribution of females is more dynamic and ephemeral compared to other resources, prompting males to traverse larger daily ranges during the mating season to locate and court females. Our work illustrates the utility of using daily movement to understand the behavioral process underlying larger space use patterns.

Wavelet Entropy Analysis of Electroencephalogram Signals During Wake and Different Sleep Stages in Patients with Insomnia Disorder.

To investigate the changes in the wavelet entropy during wake and different sleep stages in patients with insomnia disorder. Sixteen patients with insomnia disorder and sixteen normal controls were enrolled. They underwent scale assessment and two consecutive nights of polysomnography (PSG). Wavelet entropy analysis of electroencephalogram (EEG) signals recorded from all participants in the two groups was performed. The changes in the integral wavelet entropy (En) and individual-scale wavelet entropy (En(a)) during wake and different sleep stages in the two groups were observed, and the differences between the two groups were compared. The insomnia disorder group exhibited lower En during the wake stage, and higher En during the N3 stage compared with the normal control group (all P < 0.001). In terms of En(a), patients with insomnia disorder exhibited lower En(a) in the β and α frequency bands during the wake stage compared with normal controls (β band, P < 0.01; α band, P < 0.001), whereas they showed higher En(a) in the β and α frequency bands during the N3 stage than normal controls (β band, P < 0.001; α band, P < 0.001). Wavelet entropy can reflect the changes in the complexity of EEG signals during wake and different sleep stages in patients with insomnia disorder, which provides a new method and insights about understanding of pathophysiological mechanisms of insomnia disorder. Wavelet entropy provides an objective indicator for assessing sleep quality.

Sleep Patterns During Pre-Competition Training Phase: A Comparison Between Male and Female Collegiate Swimmers.

While there is a rising focus on sleep issues among athletes, a notable gap exists in the comparative analysis of sleep patterns between male and female athletes. This study aims to evaluate the sleep patterns of collegiate swimmers during a specific period (pre-competition training phase) based on the National Sleep Foundation's recommendations and compares sleep differences between males and females. 15 swimmers (6 males and 9 females) completed the Athlete Sleep Screening Questionnaire (ASSQ) and wore actigraphy devices for 8 consecutive nights to record objective sleep patterns including bedtime, wake time, sleep onset latency, total sleep time, wake after sleep onset, and sleep efficiency. The total sleep time of collegiate male (5.0±0.4 h, 4.6 to 5.4h) and female (6.0±0.7 h, 5.5 to 6.5h) swimmers was less than 7 hours per night, and male swimmers' sleep efficiency (76.7±8.9%, 67.4 to 86.0%) was lower than the 85% standard. Male swimmers had less objectively measured sleep duration (p=0.006, d=1.66, large effect), lower sleep efficiency (p=0.013, d=1.51, large effect), and longer wake after sleep onset (p=0.096, d=0.94, moderate effect). Female swimmers had higher sleep difficulty scores (p=0.06, d=1.08, moderate effect), and there was a significant difference in the distribution of sleep difficulty scores between male and female swimmers (p=0.033, V=0.045, small effect). Collegiate swimmers exhibited poor sleep patterns during pre-competition preparation, and the sleep fragmentation of male swimmers was more pronounced. There were sex differences in both subjective and objective measured sleep patterns, with male swimmers having less sleep and low efficiency, while female swimmers experienced more significant sleep disturbances.

Characterization of circulating leptin-receptor levels following acute sleep restriction: A pilot study on healthy adult females

BackgroundInsufficient sleep adversely affects energy homeostasis by decreasing leptin levels. The underlying physiological mechanisms; however, remain unclear. Circulating leptin is well described to be regulated by its soluble receptor (sOB-R). Intriguingly, the impact of short sleep duration on sOB-R levels has never been characterized. AimIn this study, we investigated, for the first time, the variation of sOB-R levels and its temporal relationship with circulating leptin upon acute sleep restriction. MethodsFive adult females were maintained on an 8-hour sleep schedule (bedtime at 00:00) for 1 week before restricting their sleep to 4.5 h (bedtime at 03:30) on 2 consecutive nights. Balanced meals were scheduled to specific hours and sleep was objectively measured. Four-hour blood samples were regularly collected during waking hours between 08:00 and 00:00. ResultsSleep restriction resulted in lower leptin (20.9 ± 1.7 vs 25.7 ± 1.7 ng/ml) and higher sOB-R concentrations (24.4 ± 1.2 vs 19.8 ± 1.6 ng/ml). Neither the discordant temporal relationship nor the pattern of leptin and sOB-R were altered in response to sleep restriction. ConclusionOur results suggest that sleep restriction may modulate circulating leptin levels and possibly metabolism via upregulating its soluble receptor. This observation may have valuable therapeutic implications when considering sOB-R as a potential target during the management of metabolic disturbances.

How turtles keep their cool: Seasonal and diel basking patterns in a tropical turtle

Behavioural thermoregulation by ectotherms is an important mechanism for maintaining body temperatures to optimise physiological performance. Experimental studies suggest that nocturnal basking by Krefft's river turtles (Emydura macquarii krefftii) in the tropics may allow them to avoid high water temperatures, however, this hypothesis has yet to be tested in the field. In this study, we examined the influence of environmental temperature on seasonal and diel patterns of basking in E. m. krefftii in tropical north Queensland, Australia. Wildlife cameras were used to document turtle basking events for seven consecutive days and nights for each month over a year (April 2020–March 2021). Air and water temperatures were recorded simultaneously using temperature loggers. We used a negative binomial mixed effects model to compare mean basking durations (min) occurring among four environmental temperature categories based on population thermal preference (26 °C): 1) air temperature above and water temperature below preferred temperature; 2) air temperature below and water temperature above preferred temperature; 3) air and water temperatures both above preferred temperature; and 4) air and water temperatures both below preferred temperature. Basking behaviour was influenced significantly by the relationship between air and water temperature. During the day, turtles spent significantly less time basking when both air and water temperatures were above their preferred temperatures. Conversely, at night, turtles spent significantly more time basking when water temperatures were warm and air temperatures were cool relative to their preferred temperature. This study adds to the growing body of work indicating pronounced heat avoidance as a thermoregulatory strategy among tropical reptile populations.

When night becomes day: Artificial light at night alters insect behavior under semi-natural conditions

Light is the most important Zeitgeber for temporal synchronization in nature. Artificial light at night (ALAN) disrupts the natural light-dark rhythmicity and thus negatively affects animal behavior. However, to date, ALAN research has been mostly conducted under laboratory conditions in this context. Here, we used the field cricket, Gryllus bimaculatus, to investigate the effect of ALAN on insect behavior under semi-natural conditions, i.e., under shaded natural lighting conditions, natural temperature and soundscape. Male crickets were placed individually in outdoor enclosures and exposed to ALAN conditions ranging from <0.01 to 1500 lx intensity. The crickets' stridulation behavior was recorded for 14 consecutive days and nights and their daily activity patterns were analysed. ALAN impaired the crickets' stridulation rhythm, evoking a change in the crickets' naturally synchronized daily activity period. This was manifested by a light-intensity-dependent increase in the proportion of insects demonstrating an intrinsic circadian rhythm (free-run behavior). This also resulted in a change in the population's median activity cycle period. These ALAN-induced effects occurred despite the crickets' exposure to almost natural conditions. Our findings provide further validity to our previous studies on ALAN conducted under lab conditions and establish the deleterious impacts of ALAN on animal behavioral patterns. TeaserArtificial light at night alters cricket behavior and desynchronizes their stridulation even under near-natural conditions.

Inter-night variability of in-home, overnight pulse oximetry screening in an asymptomatic older adult population.

Obstructive sleep apnoea (OSA) is common, yet often undiagnosed. Self-administered, overnight pulse oximetry (OPO) could screen for OSA in asymptomatic, older populations. However, the inter-night variability of OPO in an asymptomatic, older population is unknown. We determined the inter-night variability of home OPO parameters in an older population and correlated with sleep questionnaires. Participants > 50 years without a diagnosis of OSA undertook home OPO for three consecutive nights and completed two sleep questionnaires (STOP-BANG (SBQ) and Epworth Sleepiness Score (ESS)). Analysis was performed with linear mixed models and Spearman's correlation coefficient. There was no difference in oxygen desaturation index (ODI), MeanSpO2, MinimumSpO2, and time spent with SpO2 < 90% (T90) across two or three nights (P ≥ 0.282). However, the variability of all parameters across nights increased with the magnitude of departure from normal values (P ≤ 0.002). All OPO parameters were associated with age (P ≤ 0.034) and body mass index (P ≤ 0.049). There was a weak correlation between three OPO parameters and SBQ (absolute ρ = 0.22 to 0.32; P ≤ 0.021), but not ESS (P ≥ 0.254). Inter-night variability of home OPO was minimal when values were near-normal in an older population. However, as values depart from normal, the inter-night variability increases, indicating the need for multiple night recordings. Low correlation to sleep questionnaires suggest the need for more robust OSA questionnaires in an asymptomatic population.

Associations of light exposure patterns with sleep among Dutch children: The ABCD cohort study.

Light exposure affects the circadian system and consequently can affect sleep quality. Only few studies examined this relationship in children. We evaluated associations between light exposure patterns and sleep metrics in children. We measured the sleep parameters of 247 Dutch children, aged between 11 and 13 years and recruited from the ABCD cohort, using actigraphy and sleep records for 7 consecutive nights. Personal light exposures were measured with a light meter during the whole day and night. We applied generalized mixed-effects regression models, adjusted for possible confounders, to evaluate the associations of light exposure patterns on sleep duration, sleep efficiency and sleep-onset delay. In the models mutually adjusted for potential confounders, we found the amount of hours between the first time of bright light in the morning and going to sleep and the duration of bright light to be significantly associated with decreased sleep duration (in min; β: -2.02 [95% confidence interval: -3.84, -0.25], β: -8.39 [95% confidence interval: -16.70, -0.07], respectively) and with shorter sleep-onset delay (odds ratio: 0.88 [95% confidence interval: 0.80, 0.97], odds ratio: 0.40 [95% confidence interval: 0.19, 0.87], respectively). Increased light intensities at night were associated with decreased sleep duration (T2 β: -8.54 [95% confidence interval: -16.88, -0.20], T3 β: -14.83 [95% confidence interval: -28.04, -1.62]), while increased light intensities before going to bed were associated with prolonged sleep onset (odds ratio: 4.02 [95% confidence interval: 2.09, 7.73]). These findings further suggest that children may be able to influence their sleep quality by influencing the light exposure patterns during day and night.

Associations Among Cardiometabolic Risk Factors, Sleep Duration, and Obstructive Sleep Apnea in a Southeastern US Rural Community: Cross-Sectional Analysis From the SLUMBRx-PONS Study.

Short sleep and obstructive sleep apnea are underrecognized strains on the public health infrastructure. In the United States, over 35% of adults report short sleep and more than 80% of individuals with obstructive sleep apnea remain undiagnosed. The associations between inadequate sleep and cardiometabolic disease risk factors have garnered increased attention. However, challenges persist in modeling sleep-associated cardiometabolic disease risk factors. This study aimed to report early findings from the Short Sleep Undermines Cardiometabolic Health-Public Health Observational study (SLUMBRx-PONS). Data for the SLUMBRx-PONS study were collected cross-sectionally and longitudinally from a nonclinical, rural community sample (n=47) in the southeast United States. Measures included 7 consecutive nights of wrist-based actigraphy (eg, mean of 7 consecutive nights of total sleep time [TST7N]), 1 night of sleep apnea home testing (eg, apnea-hypopnea index [AHI]), and a cross-sectional clinical sample of anthropometric (eg, BMI), cardiovascular (eg, blood pressure), and blood-based biomarkers (eg, triglycerides and glucose). Correlational analyses and regression models assessed the relationships between the cardiometabolic disease risk factors and the sleep indices (eg, TST7N and AHI). Linear regression models were constructed to examine associations between significant cardiometabolic indices of TST7N (model 1) and AHI (model 2). Correlational assessment in model 1 identified significant associations between TST7N and AHI (r=-0.45, P=.004), BMI (r=-0.38, P=.02), systolic blood pressure (r=0.40, P=.01), and diastolic blood pressure (r=0.32, P=.049). Pertaining to model 1, composite measures of AHI, BMI, systolic blood pressure, and diastolic blood pressure accounted for 25.1% of the variance in TST7N (R2adjusted=0.25; F2,38=7.37; P=.002). Correlational analyses in model 2 revealed significant relationships between AHI and TST7N (r=-0.45, P<.001), BMI (r=0.71, P<.001), triglycerides (r=0.36, P=.03), and glucose (r=0.34, P=.04). Results from model 2 found that TST7N, triglycerides, and glucose accounted for 37.6% of the variance in the composite measure of AHI and BMI (R2adjusted=0.38; F3,38=8.63; P<.001). Results from the SLUMBRx-PONS study highlight the complex interplay between sleep-associated risk factors for cardiometabolic disease. Early findings underscore the need for further investigations incorporating the collection of clinical, epidemiological, and ambulatory measures to inform public health, health promotion, and health education interventions addressing the cardiometabolic consequences of inadequate sleep. RR2-10.2196/27139.

Characterization of sperm quality in captive-bred barramundi (Lates calcarifer): Effect on spawning performance and paternal contribution in mass-spawning events

Barramundi (Asian sea bass, Lates calcarifer) is a species with a mass-spawning reproductive strategy whereby adults synchronously release their gametes into the water column. In captivity, this reproductive strategy usually results in uneven paternal contributions to each cohort of progeny, creating skews in family size that hinder the effectiveness of selective breeding programs. As sperm quality influences fertilization success and early larval development, we investigated the relationship between sperm quality and spawning performance. Accordingly, we assessed three established breeding cohorts. Sperm samples (n = 22) were collected by cannulation. Sperm motility was assessed using CASA, and sperm viability and DNA integrity were evaluated using dual-fluorescence stains by flow cytometry. Broodstock were induced to spawn across two consecutive nights, and offspring were collected at 2.5 h and 12 h post-fertilization (hpf) and 24 h and 48 h post-hatching (hph). Offspring were assessed for morphological abnormalities, and key morphological parameters were recorded. Offspring collected at 2.5 hpf and 24 hph were genotyped to determine their parentage and examine the relationship between sperm quality of individual males and offspring survival. Results highlighted that male condition factor (K) and sperm quality were highly variable within each breeding cohort. Males with a lower condition factor showed lower sperm motility and velocity. In contrast, males with a higher condition factor showed higher sperm motility and velocity but also higher levels of sperm DNA damage. While all males were capable of fertilization, males with a lower condition factor had greater paternal contribution. In this study, a reduction in skewed paternity was also found on Night 2 of spawning compared to Night 1. Moreover, males from Tank B, which had the lowest level of sperm DNA damage, had the most even paternal contribution. Conversely, highly skewed maternal contributions were reported across all spawning events. The results of this study suggest that additional complex dynamics and further unmeasured variables, such as spawning behavior, social hierarchy, and the spawning induction procedure, may also skew family sizes. Therefore, further development of artificial reproductive technology is recommended to gain greater control over individual contribution and overcome current breeding bottlenecks.

Sperm traits and seminal plasma proteome of locally adapted hairy rams subjected to intermittent scrotal insulation

The present study evaluated the effects of heat stress on reproductive parameters of hairy rams. Six animals were subjected to scrotal insulation during four consecutive nights (6 PM – 6 AM). Day (D) 0 was the first day of insulation. Scrotal circumference increased from 30.5 ± 0.3 cm (at pre-insulation) to 31.8 ± 0.4 cm on D4, decreased 3.9 cm on D28, returning to 30.6 ± 0.6 cm on D57. Sperm concentration decreased from 3.7 ± 0.12 ×109 sperm/mL before insulation to 2.6 ± 0.1 ×109 on D23, returning to normal on D57. Sperm motility averaged 75 ± 2.9% before insulation, was undetectable on D23, and became normal on D77. Sperm with normal morphology reached 5.9 ± 2.6% on D35 but recovered (86.8 ± 2.1%) on D91. Sperm DNA integrity decreased from 86.5 ± 4.7% before insulation to 11.1 ± 3.7% on D63, returning to pre-insulation values on D120. Sperm BSP immunostaining was reduced after scrotal insulation. Variations in seminal protein abundances coincided with changes in sperm parameters. Seminal plasma superoxide dismutase, carboxypeptidase Q-precursor and NPC intracellular cholesterol transporter 2 decreased on D18, returning to normal after D28. Albumin, inhibitor of carbonic anhydrase precursor, EGF-like repeat and discoid I-like domain-containing protein 3 and polymeric immunoglobulin receptor increased after insulation. In summary, intermittent scrotal insulation drastically altered ram sperm attributes and seminal proteins, especially those associated with oxidative stress. Knowledge of animal´s response to thermal stress is vital in the scenario of climate changes.

Comparison of actigraphy with a sleep protocol maintained by professional caregivers and questionnaire-based parental judgment in children and adolescents with life-limiting conditions

BackgroundActigraphy offers a promising way to objectively assess pediatric sleep. Aim of the study was investigating the extent to which actigraphy used in children and adolescents with life-limiting conditions is consistent with two other measures of sleep diagnostics.MethodsIn this monocentric prospective study N = 26 children and adolescents with life-limiting conditions treated on a pediatric palliative care unit were assessed. For three consecutive nights they wore an actigraph; the 24-hours sleep protocol documented by nurses and the Sleep Screening for Children and Adolescents with Complex Chronic Conditions (SCAC) answered by parents were analyzed. Patient characteristics and the parameters sleep onset, sleep offset, wake after sleep onset (WASO), number of wake phases, total sleep time (TST) and sleep efficiency (SE) were descriptively examined. Percentage bend correlations evaluated the three measures’ concordance.ResultsDescriptively, and except for the number of waking episodes, the different measures’ estimations were comparable. Significant correlations existed between actigraphy and the sleep protocol for sleep onset (r = 0.83, p = < 0.001) and sleep offset (r = 0.89, p = < 0.001), between actigraphy and SCAC for SE (r = 0.59, p = 0.02).ConclusionAgreement of actigraphy with the focused sleep measures seems to be basically given but to varying degrees depending on the considered parameters.

Dream incorporation of three different bodily stimuli

Introduction Lucid dreaming opens the possibility to rehearse sport skills within a dream while sleeping (Peters et al. 2023; Stumbrys et al. 2016). But so far, no induction techniques have been developed to induce reliable lucid dreams. One potential technique is to apply external stimulation while a person is sleeping in order to send a hint into the dream which might enhance lucidity in the ongoing dream. Several studies have tested dream incorporation rates (DIR) with different stimuli and different results (Schredl, 2018), but none with a larger sample size and a within-design. Furthermore, in this study we wanted to explore body related stimulations to evoke in future studies lucid dreams. Methods 10-Channel polysomnography and three different bodily stimulation methods were combined during three consecutive test nights with each night using one stimulation method (plus adaptation night). The three stimulation methods consisted of electrical forearm muscle stimulation (EMS), galvanic vestibular stimulation (GVS), and haptic vibration stimulation (HS). During REM sleep, one of the three stimuli was presented or a sham condition was applied in a counterbalanced order. The stimuli were followed by REM awakenings, resulting in corresponding verbal dream reports. With the help of those reports, the translation from a physical arm movement, vestibular sensation and vibration into the dream environment was investigated using dream content analysis. Movement of the dream arm, balance related activity and tactile or somatosensory sensations targeted the dream incorporations of EMS, GVS and HS respectively. Results Movement of the arm was present in 23.2%, 8.1% and 23.5% of EMS, GVS and HS dreams respectively. Balance-related activity was present in 6.1%, 7.9% and 5.8% of EMS, GVS and HS dreams respectively. Finally, tactile and somatosensory sensations were present in 13.6%, 0% and 6.3% of the EMS, GVS and HS dreams respectively. After correcting for sham condition, tactile and somatosensory sensations on the EMS dreams seem to be the strongest incorporation effect upon stimulation. Discussion/Conclusion We tested dream incorporation of three different stimulation methods using a within-design on a larger sample size, a method that has never been attempted before. GVS appears unsuccessful in altering dream content, but this might be confounded due to challenges in methodology. EMS evokes the most dream incorporation in the scale of tactile and somatosensory dream content followed by HS. The investigation of the incorporation of external kinesthetic stimulation into dream content represents a fundamental contribution to various scientific fields and could foster future research on lucid dream induction, enabling the further exploration of sport practice in a sleep state.

Latency to N3 interruption in arousal disorders.

To help expert witnesses in criminal cases using the "sleepwalking defense," we studied the time of first and last interruptions from stage N3 in patients with arousal disorders, including sexsomnia, as well as their determinants. The epochs of lights off, sleep onset, first N3 interruption (with and without behaviors), and last N3 interruption were determined by videopolysomnography on two consecutive nights in 163 adults with disorders of arousal, including 46 with and 117 without sexsomnia. The first N3 interruption (independently of concomitant behavior) occurred as early as 8 minutes after sleep onset and within 100 minutes of falling asleep in 95% of cases. The first motor arousal from N3 occurred as early as 25 minutes after lights off time, a timing more variable between participants (between 30 and 60 minutes after lights off time in 25% of participants and within 60 minutes of falling asleep in 50%). These latencies did not differ between the groups with and without sexsomnia. No correlation was found between these latencies and the young age, sex, or clinical severity. The latency of motor arousals was shorter when they were associated with a fast-wave EEG profile and were not preceded by another type of N3 arousal. The first motor arousal may occur early in the night in patients with arousal disorders, with or without sexsomnia, suggesting that abnormal behaviors occurring as early as 25 minutes after lights off time in clinical and criminal cases can be a parasomnia manifestation.