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Purpose: Transmeridian travel is common for elite athletes participating in competitions and training. However, this travel can lead to circadian misalignment wherein the internal biological clock becomes desynchronized with the light–dark cycle of the new environment, resulting in performance decrement and potential negative health consequences. Existing literature extensively discusses recommendations for managing jet lag, predominantly emphasizing light-based interventions to synchronize the internal clock with the anticipated time at the destination. Nevertheless, visually impaired (VI) athletes may lack photoreceptiveness, diminishing or nullifying the effectiveness of this therapy. Consequently, this invited commentary explores alternative strategies for addressing jet lag in VI athletes. Conclusions: VI athletes with light perception but reduced visual acuity or visual fields may still benefit from light interventions in managing jet lag. However, VI athletes lacking a conscious perception of light should rely on gradual shifts in behavioral factors, such as meal timing and exercise, to facilitate the entrainment of circadian rhythms to the destination time. Furthermore, interventions like melatonin supplementation may prove useful during and after travel. In addition, it is recommended that athlete guides adopt phase-forward or phase-back approaches to synchronize with the athlete, aiding in jet-lag management and optimizing performance. [ABSTRACT FROM AUTHOR]

Notonecta species (Hemiptera: Notonectidae) are generalist true predators with a strong impact on the size, structure, and richness of the aquatic communities, particularly on mosquito populations. Juvenile and adult backswimmers not only prey on mosquito larvae (consumptive effect) but their presence can also deter the oviposition of gravid mosquito females (non‐consumptive effect). In this study, we selected a Western Palearctic backswimmer, Notonecta maculata Fabricius, as a predator and deterrent of the highly invasive and health‐threatening Asian tiger mosquito, Aedes albopictus (Skuse) (Diptera: Culicidae). In central Italy, N. maculata is univoltine and overwinters in the adult stage. Females lay eggs from February to the end of May, and the first new adults will emerge in late June; the complete nymphal development requires 44.5 ± 3.1 days. The number of Ae. albopictus larvae preyed on by N. maculata during its growth increases while developing, going from 0.03 ± 0.02 larvae per day for first instar nymphs to 21.38 ± 2.90 for mature adults. Furthermore, the presence of a single N. maculata adult in a mosquito ovitrap is enough to discourage the Ae. albopictus oviposition for up to 5 days. Limiting mosquito populations and, consequently, the transmission of viruses and parasites should be our main goal. Therefore, the integrated management of Ae. albopictus by the use of insecticides and a predator (such as backswimmer juveniles and adults), even if only in specific situations, may be promising and feasible. A more in‐depth knowledge of the biological cycle of N. maculata could help, consequently, to optimize its mass rearing. [ABSTRACT FROM AUTHOR]

Available data shows associations between chronotype, circadian rhythms, sleep quality and fibromyalgia (FM) presentation. However, no studies have explored links between the chronobiological variables and effectiveness of pharmacotherapy. We aimed to assess the chronotypes, circadian rhythms, sleep-wake cycle and sleep quality in FM and their links to treatment response to serotonin and noradrenalin reuptake inhibitors (SNRI). 60 FM patients: 30 responsive to SNRI (FM T[+]), 30 non-responsive to SNRI (FM T[-]) and 30 healthy controls participated. Subjects were assessed by physician and with questionnaire tools: Composite Scale of Morningness, Biological Rhythms Interview of Assessment in Neuropsychiatry, Sleep-Wake Pattern Assessment Questionnaire, Pittsburgh Sleep Quality Index and Fibromyalgia Impact Questionnaire. ANOVA analysis and simple logistic regressions were used to examine the relationships between chronological variables and response to SNRI. FM T[-] vs. FM T[+] presented lower morning affect (11.50[95%CI 9.96-13.04] vs. 14.00[95%CI 12.42-15.57];p=0.04), anytime wakeability (2.27[95%CI 1.4-3.13] vs. 4.03[95%CI 2.99-5.08];p=0.013) worse overall (11.40[95%CI 9.92-12.88] vs. 7.97[95%CI 6.75-9.19];p=0.002) and subjective (1.70[95%CI 1.30-2.01] vs. 1.17[95%CI 0.94-1.39];p=0.008) sleep quality, higher circadian rhythm disruptions (55.47[95%CI 52.32-58.62] vs. 44.97[95%CI 41.31-48.62];p<0.001), sleep disturbances (1.63[95%CI 1.38-1.68] vs. 1.30[95%CI 1.1-1.5];p=0.04), sleeping-medication use (1.80[95%CI 1.27-2.32] vs. 0.70[95%CI 0.28-1.12];p=0.003). Levels of morningness (AIC=82.91,OR=0.93,p=0.05), morning affect (AIC=81.901,OR=0.86,p=0.03) diurnal dysrhythmia (AIC=69.566,OR=1.14,p<0.001), anytime wakeability (AIC=80.307,OR=0.76,p=0.015), overall sleep quality (AIC=74.665, OR=1.31,p=0.002) subjective sleep quality (AIC=79.353, OR=2.832,p=0.01) and disturbances (AIC=82.669,OR=2.54,p=0.043), sleep medication use (AIC=77.017, OR=1.9,p=0.003) and daytime disfunction (AIC=82.908, OR=1.971,p=0.049) were predictors of non-response to SNRI. Chronobiological variables vary between FM T[+] and FM T[-] and are predictors of non-response to SNRI. [ABSTRACT FROM AUTHOR]

Biological aging is near-ubiquitous in the animal kingdom, but its timing and pace vary between individuals and over lifespans. Prospective, individual-based studies of wild animals—especially non-human primates—help identify the social and environmental drivers of this variation by indicating the conditions and exposure windows that affect aging processes. However, measuring individual biological age in wild primates is challenging because several of the most promising methods require invasive sampling. Here, we leverage observational data on behavior and physiology, collected non-invasively from 319 wild female baboons across 2402 female-years of study, to develop a composite predictor of age: the non-invasive physiology and behavior (NPB) clock. We found that age predictions from the NPB clock explained 51% of the variation in females' known ages. Further, deviations from the clock's age predictions predicted female survival: females predicted to be older than their known ages had higher adult mortality. Finally, females who experienced harsh early-life conditions were predicted to be about 6 months older than those who grew up in more benign conditions. While the relationship between early adversity and NPB age is noisy, this estimate translates to a predicted 2–3 year reduction in mean adult lifespan in our model. A constraint of our clock is that it is tailored to data collection approaches implemented in our study population. However, many of the clock's components have analogs in other populations, suggesting that non-invasive data can provide broadly applicable insight into heterogeneity in biological age in natural populations. [ABSTRACT FROM AUTHOR]

Connectomics research is making rapid advances, although models revealing general principles of connectional architecture are far from complete. Our analysis of 106 published connection reports indicates that the adult rat brain interregional connectome has about 76,940 of a possible 623,310 axonal connections between its 790 gray matter regions mapped in a reference atlas, equating to a network density of 12.3%. We examined the sexually dimorphic network using multiresolution consensus clustering that generated a nested hierarchy of interconnected modules/subsystems with three first-order modules and 157 terminal modules in females. Top-down hierarchy analysis suggests a mirror-image primary module pair in the central nervous system's rostral sector (forebrain-midbrain) associated with behavior control, and a single primary module in the intermediate sector (rhombicbrain) associated with behavior execution; the implications of these results are considered in relation to brain development and evolution. Bottom-up hierarchy analysis reveals known and unfamiliar modules suggesting strong experimentally testable hypotheses. Global network analyses indicate that all hubs are in the rostral module pair, a rich club extends through all three primary modules, and the network exhibits small-world attributes. Simulated lesions of all regions individually enabled ranking their impact on global network organization, and the visual path from the retina was used as a specific example, including the effects of cyclic connection weight changes from the endogenous circadian rhythm generator, suprachiasmatic nucleus. This study elucidates principles of interregional neuronal network architecture for a mammalian brain and suggests a strategy for modeling dynamic structural connectivity. [ABSTRACT FROM AUTHOR]

The biological clock of the suprachiasmatic nucleus (SCN) orchestrates circadian (approximately daily) rhythms of behaviour and physiology that underpin health. SCN cell‐autonomous time‐keeping revolves around a transcriptional/translational feedback loop (TTFL) within which PERIOD (PER1,2) and CRYPTOCHROME (CRY1,2) proteins heterodimerise and suppress trans‐activation of their encoding genes (Per1,2; Cry1,2). To explore its contribution to SCN time‐keeping, we used adeno‐associated virus–mediated translational switching to express PER2 (tsPER2) in organotypic SCN slices carrying bioluminescent TTFL circadian reporters. Translational switching requires provision of the non‐canonical amino acid, alkyne lysine (AlkK), for protein expression. Correspondingly, AlkK, but not vehicle, induced constitutive expression of tsPER2 in SCN neurons and reversibly and dose‐dependently suppressed pPer1‐driven transcription in PER‐deficient (Per1,2‐null) SCN, illustrating the potency of PER2 in negative regulation within the TTFL. Constitutive expression of tsPER2, however, failed to initiate circadian oscillations in arrhythmic PER‐deficient SCN. In rhythmic, PER‐competent SCN, AlkK dose‐dependently reduced the amplitude of PER2‐reported oscillations as inhibition by tsPER2 progressively damped the TTFL. tsPER2 also dose‐dependently lengthened the period of the SCN TTFL and neuronal calcium rhythms. Following wash‐out of AlkK to remove tsPER2, the SCN regained TTFL amplitude and period. Furthermore, SCN retained their pre‐washout phase: the removal of tsPER2 did not phase‐shift the TTFL. Given that constitutive tsCRY1 can regulate TTFL amplitude and period, but also reset TTFL phase and initiate rhythms in CRY‐deficient SCN, these results reveal overlapping and distinct properties of PER2 and CRY1 within the SCN, and emphasise the utility of translational switching to explore the functions of circadian proteins. [ABSTRACT FROM AUTHOR]

Defibrillation remains the optimal therapy for terminating ventricular fibrillation (VF) in out‐of‐hospital cardiac arrest (OHCA) patients, with reported shock success rates of ∼90%. A key persistent challenge, however, is the high rate of VF recurrence (∼50–80%) seen during post‐shock cardiopulmonary resuscitation (CPR). Studies have shown that the incidence and time spent in recurrent VF are negatively associated with neurologically‐intact survival. Recurrent VF also results in the administration of extra shocks at escalating energy levels, which can cause cardiac dysfunction. Unfortunately, the mechanisms underlying recurrent VF remain poorly understood. In particular, the role of chest‐compressions (CC) administered during CPR in mediating recurrent VF remains controversial. In this review, we first summarize the available clinical evidence for refibrillation occurring during CPR in OHCA patients, including the postulated contribution of CC and non‐CC related pathways. Next, we examine experimental studies highlighting how CC can re‐induce VF via direct mechano‐electric feedback. We postulate the ionic mechanisms involved by comparison with similar phenomena seen in commotio cordis. Subsequently, the hypothesized contribution of partial cardiac reperfusion (either as a result of CC or CC independent organized rhythm) in re‐initiating VF in a globally ischaemic heart is examined. An overview of the proposed ionic mechanisms contributing to VF recurrence in OHCA during CPR from a cellular level to the whole heart is outlined. Possible therapeutic implications of the proposed mechanistic theories for VF recurrence in OHCA are briefly discussed. [ABSTRACT FROM AUTHOR]

Background: The natural light environment is far more complex than that experienced by animals under laboratory conditions. As a burrowing species, wild mice are able to self-modulate their light exposure, a concept known as light environment sampling behaviour. By contrast, under laboratory conditions mice have little opportunity to exhibit this behaviour. To address this issue, here we introduce a simple nestbox paradigm to allow mice to self-modulate their light environment. Dark nestboxes fitted with passive infrared sensors were used to monitor locomotor activity, circadian entrainment, decision making and light environment sampling behaviour. Results: Under these conditions, mice significantly reduce their light exposure to an average of just 0.8 h across a 24 h period. In addition, mice show a distinct pattern of light environment sampling behaviour, with peaks at dawn and dusk under a ramped light dark cycle. Furthermore, we show that the timing of light environment sampling behaviour depends upon endogenous circadian rhythms and is abolished in mice lacking a circadian clock, indicating a feedback loop between light, the circadian clock and behaviour. Conclusions: Our results highlight the important role of behaviour in modifying the light signals available for circadian entrainment under natural conditions. [ABSTRACT FROM AUTHOR]

Circadian clock properties vary between individuals and relate to variation in entrained timing in captivity. How this variation translates into behavioural differences in natural settings, however, is poorly understood. Here, we tested in great tits whether variation in the free‐running period length (tau) under constant dim light (LL) was linked to the phase angle of the entrained rhythm (“chronotype”) in captivity and in the wild, as recently indicated in our study species. We also assessed links between tau and the timing of first activity onset and offset under LL relative to the last experienced light–dark (LD) cycle. We kept 66 great tits, caught in two winters, in LL for 14 days and subsequently released them with a radio transmitter back to the wild, where their activity and body temperature rhythms were tracked for 1 to 22 days. For a subset of birds, chronotype was also recorded in the lab before release. Neither wild nor lab chronotypes were related to tau. We also found no correlation between lab and wild chronotypes. However, the first onset in LL had a positive relationship with tau, but only in males. Our results demonstrate that links between tau and phase of entrainment, postulated on theoretical grounds, may not consistently hold under natural conditions, possibly due to strong masking. This calls for more holistic research on how the many components of the circadian system interact with the environment to shape timing in the wild.Wild birds showed chronotypes in the field that were unlinked to their circadian period length tau measured in captivity. In males only, the first onset of activity after exposure to constant dim light did correlate with tau. Our study emphasises the need to investigate clocks in the real world, including a need to better understand masking. [ABSTRACT FROM AUTHOR]

Organisms on Earth are known to evolve by cooperating with their neighbors in external environments. These cooperating organisms are under the influence of circadian rhythms derived from Earth's rotation and have various biological rhythms within them. However, little is known about the effects of these rhythms on the cooperation of organisms. In this study, we investigate the effects of the biological rhythms on the survival of cooperators in evolution using evolutionary game theory. We focused on the rhythm in reproduction among the various biological rhythms that organisms have. Our results are as follows. Rhythmic reproductions play a role in limiting the survival of cooperators; they reduce the survival limits of cooperators compared to when there is no rhythm. Their limiting force is sensitive to the number of interacting neighbors, however. When the number of interacting neighbors is relatively small, the effects of rhythm in reproduction on the survival limits of cooperators are not significant. As the number of interacting neighbors increases, the limiting force of rhythmic reproductions becomes more powerful, gradually decreasing the survival limits of cooperators. Variations of rhythm in reproduction do not alter the survival limits; they only cause fluctuations in the population of cooperators within the survival limits. Our findings suggest that the rhythmic reproductions in evolution determine the survival domain of cooperators, where the number of interacting neighbors is a major factor along with rhythmic reproductions. Organisms under the constant pressure imposed by rhythmic reproductions may need to find the optimal number of interacting neighbors to survive and evolve to a new level through cooperation. [ABSTRACT FROM AUTHOR]

Chronopharmacology is a multidisciplinary field that investigates the impact of biological rhythms on drug effects and responses. It aims to optimize drug therapy by considering the timing and rhythm characteristics of biological events. Chronopharmacology focuses on designing drug dosing schedules that align with the body's natural biological rhythms, enhancing drug efficacy and safety while reducing adverse reactions. This approach holds significant promise in pharmacology and drug therapy, as it can revolutionize medication administration and patient care. Chronotherapeutics involves timing interventions such as surgery, physical agents, and psychotherapy to minimize toxicity and enhance treatment efficacy. It benefits translational medicine by considering underlying circadian rhythms in drug pharmacology, including pharmacokinetics and pharmacodynamics, as well as patients' physiology and disease pathology. Recent research focuses on targeting treatments toward rhythm-generating biologic timing systems to improve outcomes. Chronopharmacology has shown potential advantages in treating disorders such as peptic ulcer disease, cancer, allergic rhinitis, and rheumatoid arthritis. Challenges for chronopharmacology include lack of translation research, variability in therapeutic responses, replication of findings, optimized drug dosing schedules, clinical implementation, clock disruption, and standardization of chronopharmacological guidelines. In terms of pharmacology and medication therapy, chronopharmacology has a lot of promise. This strategy has the potential to change medicine administration and enhance patient care by utilizing biological rhythms and optimizing drug dose schedules. To fully realize the promise of chronopharmacology in clinical practice, additional study and validation of findings are required. [ABSTRACT FROM AUTHOR]

Sleep and biological rhythms are integral to mood regulation across the lifespan, particularly in bipolar disorder (BD), where alterations in sleep phase, structure, and duration occur in all mood states. These disruptions are linked to poorer quality of life, heightened suicide risk, impaired cognitive function, and increased relapse rates. This review highlights the pathophysiology of sleep disturbances in BD and aims to consolidate understanding and clinical applications of these phenomena. It also summarizes the evolution of sleep and biological rhythms assessment methods, including ecological momentary assessment (EMA) and digital phenotyping. It underscores the importance of recognizing circadian rhythm involvement in mood regulation, suggesting potential therapeutic targets. Future research directions include elucidating circadian clock gene mechanisms, understanding environmental impacts on circadian rhythms, and investigating the bidirectional relationship between sleep disturbances and mood regulation in BD. Standardizing assessment methods and addressing privacy concerns related to EMA technology and digital phenotyping are essential for advancing research. Collaborative efforts are crucial for enhancing clinical applicability and understanding the broader implications of biological rhythms in BD diagnosis and treatment. Overall, recognizing the significance of sleep and biological rhythms in BD offers promise for improved outcomes through targeted interventions and a deeper understanding of the disorder's underlying mechanisms. [ABSTRACT FROM AUTHOR]

Phenology and photosynthetic capacity both regulate carbon uptake by vegetation. Previous research investigating the impact of phenology on vegetation productivity has focused predominantly on the start and end of growing seasons (SOS and EOS), leaving the influence of peak phenology metrics—particularly in typical climatic transition zones—relatively unexplored. Using a 24-year (2000–2023) enhanced vegetation index (EVI) dataset from the Moderate Resolution Imaging Spectroradiometer (MODIS), we extracted and examined the spatiotemporal variation for peak of season (POS) and peak growth (defined as EVImax) of forest vegetation in the Funiu Mountain region, China. In addition to quantifying the factors influencing the peak phenology metrics, the relationship between vegetation productivity and peak phenological metrics (POS and EVImax) was investigated. Our findings reveal that POS and EVImax showed advancement and increase, respectively, negatively and positively correlated with vegetation productivity. This suggested that variations in EVImax and peak phenology both increase vegetation productivity. Our analysis also showed that EVImax was heavily impacted by precipitation, whereas SOS had the greatest effect on POS variation. Our findings highlighted the significance of considering climate variables as well as biological rhythms when examining the global carbon cycle and phenological shifts in response to climate change. [ABSTRACT FROM AUTHOR]

The biological clock in eukaryotes controls daily rhythms in physiology and behavior. It displays a complex organization that involves the molecular transcriptional clock and the redox oscillator which may coordinately work to control cellular rhythms. The redox oscillator has emerged very early in evolution in adaptation to the environmental changes in O2 levels and has been shown to regulate daily rhythms in glycerolipid (GL) metabolism in different eukaryotic cells. GLs are key components of lipid droplets (LDs), intracellular storage organelles, present in all living organisms, and essential for energy and lipid homeostasis regulation and survival; however, the cell bioenergetics status is not constant across time and depends on energy demands. Thus, the formation and degradation of LDs may reflect a time-dependent process following energy requirements. This work investigated the presence of metabolic rhythms in LD content along evolution by studying prokaryotic and eukaryotic cells and organisms. We found sustained temporal oscillations in LD content in Pseudomonas aeruginosa bacteria and Caenorhabditis elegans synchronized by temperature cycles, in serum-shock synchronized human embryonic kidney cells (HEK 293 cells) and brain tumor cells (T98G and GL26) after a dexamethasone pulse. Moreover, in synchronized T98G cells, LD oscillations were altered by glycogen synthase kinase-3 (GSK-3) inhibition that affects the cytosolic activity of the metabolic oscillator or by knocking down LIPIN-1, a key GL synthesizing enzyme. Overall, our findings reveal the existence of metabolic oscillations in terms of LD content highly conserved across evolutionary scales notwithstanding variations in complexity, regulation, and cell organization. [ABSTRACT FROM AUTHOR]

Theta-burst stimulation (TBS), a patterned brain stimulation technique that mimics rhythmic bursts of 3–8 Hz endogenous brain rhythms, has emerged as a promising therapeutic approach for treating a wide range of brain disorders, though the neural mechanism of TBS action remains poorly understood. We investigated the neural effects of TBS using intracranial EEG (iEEG) in 10 pre-surgical epilepsy participants undergoing intracranial monitoring. Here we show that individual bursts of direct electrical TBS at 29 frontal and temporal sites evoked strong neural responses spanning broad cortical regions. These responses exhibited dynamic local field potential voltage changes over the course of stimulation presentations, including either increasing or decreasing responses, suggestive of short-term plasticity. Stronger stimulation augmented the mean TBS response amplitude and spread with more recording sites demonstrating short-term plasticity. TBS responses were stimulation site-specific with stronger TBS responses observed in regions with strong baseline stimulation effective (cortico-cortical evoked potentials) and functional (low frequency phase locking) connectivity. Further, we could use these measures to predict stable and varying (e.g. short-term plasticity) TBS response locations. Future work may integrate pre-treatment connectivity alongside other biophysical factors to personalize stimulation parameters, thereby optimizing induction of neuroplasticity within disease-relevant brain networks. Neural mechanisms underpinning theta burst stimulation (TBS) and its implications for neuropsychiatric disorders are not fully understood. Here authors show theta burst stimulation delivered by intracranial electrodes results in measurable responses that change over time, suggestive of neuroplasticity. These responses can be predicted by baseline biophysical parameters such as functional connectivity. [ABSTRACT FROM AUTHOR]

Social jetlag (SJL), resulting from misalignment between biological rhythms and social schedules, has emerged as a prevalent phenomenon in modern society, particularly among young athletes. However, the effect of SJL on performance is poorly studied. Jump and dynamic balance are two key skills in volleyball, as the first allows the player to perform better both during the offense and defense phase, and the second is fundamental in landing and in injury prevention. Therefore, our aim was to investigate the effect of SJL on jump skill performance and balance in female volleyball players. Thirty female volleyball players (mean age: 17.3 ± 0.88 years) participated in the study. SJL was assessed using the Munich ChronoType Questionnaire (MCTQ), integrated with Jankowsky's sleep-corrected formula. Jump skill performance was evaluated using a standardized jump test, the Vertec Jump Test, while balance was assessed with the Y Balance Test. The tests were performed at 09:00 a.m. and at 06:00 p.m. The results revealed that players with greater SJL exhibited decreased jump performance, characterized by lower vertical jump height (p = 0.02). Furthermore, players with lower SJL showed the typical difference between morning and afternoon performance (p = 0.001), demonstrating their synchronization between biological rhythms and social commitments, while no statistically significant difference between the two sessions was shown in players with higher SJL. Regarding balance, no significant association with SJL was found, but the morning session yielded lower results than the afternoon one (p = 0.01). These findings highlight the detrimental impact of SJL on jump skill performance, underscoring the importance of optimizing sleep-wake schedules and circadian alignment to enhance athletic performance. Future research should explore targeted interventions, such as sleep hygiene education, to minimize social jetlag and promote optimal performance in adolescent athletes. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the behavioral responses and circadian rhythms of mice to both rapid and gradual increases in photoperiod, mimicking the transition from winter to summer, which is associated with a heightened prevalence of hospitalizations for mania and suicidal behavior. Behavioral tests were performed in C57BL/6 male mice exposed to a transitional photoperiod, from short to long durations. To determine if circadian rhythms are affected, we measured spontaneous locomotor activity and body temperature. Mice exhibited heightened exploratory and risk‐taking behaviors compared with equatorial and static long (16:8 h of light–dark cycle for several days) groups. These behaviors were prevented by lithium. Spontaneous locomotor activity and body temperature rhythms persisted and were effectively synchronized; however, the relative amplitude of activity and interdaily stability were diminished. Additionally, the animals displayed increased activity during the light phase. Photoperiodic transition modulates behavior and circadian rhythms, mirroring certain features observed in bipolar disorder patients. This study introduces an animal model for investigating mania‐like behavior induced by photoperiodic changes, offering potential insights for suicide prevention strategies and the management of mood disorders. [ABSTRACT FROM AUTHOR]

Using the Duffing equation to model body temperature’s circadian rhythms, we simulated four cases with varying driving force parameters γ (0.32, 0.33, 0.34, and 0.35). We compared these simulations to published experimental data using Fourier and entropy analyses along Poincaré sections. For normal work-sleep conditions (γ = 0.35), the system showed precise resetting at specific times. Under shift work conditions (γ = 0.34), resetting behavior was reduced, causing a phase shift in the rhythm. Long-term constant temperature conditions (γ = 0.33) displayed a reset at the period’s start, similar to normal conditions. With no external driving forces (γ = 0.32), multiple resets occurred within the period, emphasizing the need for frequent resets to maintain stability. The simulation results align partially with experimental data, highlighting the system’s adaptability to external changes. [ABSTRACT FROM AUTHOR]

It has been found that the intraday dynamics of body temperature in small mammal and bird species on the adjacent day are similar. Therefore, by focusing on the body temperature dynamics of the previous day, it is possible to predict with a high degree of accuracy the periods of increase and decrease in body temperature for the current day. This phenomenon was observed when animals were kept under natural illumination and under artificial illumination when the phase of the intrinsic circadian rhythm shifted by 1-2 h every day. When analyzing this phenomenon in birds, it has been shown that the best match for body temperature dynamics occurs when comparing adjacent days based on sidereal days (a period of 23 h and 56 min). Over time, after several days, the daily patterns of body temperature fluctuation take on a completely different form and frequency. These facts suggest a connection between ultradian rhythms and the rotation of the Earth around its axis, and consequently, the position of animals on the surface of the planet relative to space objects. [ABSTRACT FROM AUTHOR]

In cave environments, stable conditions devoid of light-dark cycles and temperature fluctuations sustain circadian clock mechanisms across various species. However, species adapted to these conditions may exhibit disruption of circadian rhythm in locomotor activity. This study examines potential rhythm loss due to convergent evolution in five semi-aquatic troglobitic isopod species (Crustacea: Styloniscidae), focusing on its impact on locomotor activity. The hypothesis posits that these species display aperiodic locomotor activity patterns. Isopods were subjected to three treatments: constant red light (DD), constant light (LL), and light-dark cycles (LD 12:12), totaling 1656 h. Circadian rhythm analysis employed the Sokolove and Bushell periodogram chi-square test, Hurst coefficient calculation, intermediate stability (IS), and activity differences for each species. Predominantly, all species exhibited an infradian rhythm under DD and LL. There was synchronization of the locomotor rhythm in LD, likely as a result of masking. Three species displayed diurnal activity, while two exhibited nocturnal activity. The Hurst coefficient indicated rhythmic persistence, with LD showing higher variability. LD conditions demonstrated higher IS values, suggesting synchronized rhythms across species. Significant individual variations were observed within species across the three conditions. Contrary to the hypothesis, all species exhibited synchronization under light-dark conditions. Analyzing circadian activity provides insights into organism adaptation to non-cyclical environments, emphasizing the importance of exploring underlying mechanisms. [ABSTRACT FROM AUTHOR]

First, significantly higher mate-finding success was found under light condition than under constant darkness condition in Phauda flammans, a typical diurnal moth. We speculate that mate-finding behavior in P. flammans may be influenced by the light-sensitive opsin genes Long wavelength opsin (PfLW), Ultraviolet opsin (PfUV) and Blue opsin (PfBL), which are potentially regulated by both light-cues and endogenous circadian rhythms. Second, the circadian clock genes Period (PfPer), Timeless (PfTim), Cryptochrome1 (PfCry1), Cryptochrome2 (PfCRY2), Cryptochrome3 (PfCry-like), Clock (PfClk), Cycle (PfCyc), Vrille (PfVri), and Slimb (PfSli) were identified in P. flammans. Third, circadian rhythms in the relative expression levels of opsin and circadian clock genes were demonstrated via quantitative real-time PCR analysis, with peak expression coinciding with the mate-finding peak. Notably, the relative expression of PfLW in males P. flammans was significantly higher than that in females P. flammans at the mate-finding peaks Zeitgeber time (ZT) 8 and ZT 10 under light, while the expression of the opsin gene PfBL showed a similar pattern at ZT 10 under light. Additionally, the expression of the clock gene PfCry-like was significantly higher in males than in females at ZT 8 and ZT 10 under light, while PfPer, PfTim, PfClk and PfCyc exhibited similar male-biased expression patterns at ZT 10 under light. Conversely, PfCry1 and PfVri expression was significantly higher in females than in male at ZT 8 under light. In conclusion, sex differences were detected in the expression of opsin and circadian clock genes, which indicated that light-mediated regulation of these genes may contribute to the daytime mate-finding behavior of P. flammans. [ABSTRACT FROM AUTHOR]

Breast milk provides numerous benefits for both the baby and the mother, making it a unique and valuable food. The World Health Organization and the United Nations International Children's Emergency Found (UNICEF) state that exclusive breastfeeding in the first six months of life is an important strategy for reducing mortality and morbidity in infants. The circadian rhythm formation, which starts in the mother's womb, continues after the baby is born. Breast milk plays an active role in regulating the baby's circadian rhythm through the hormones, basic immune factors and bioactive components it contains, as well as meeting almost all nutritional elements for babies. Since the neural control mechanisms in the newborn are not yet fully developed, breast milk undertakes the task of helping the biological rhythms in the regulation of the infant's sleep-wake cycles, thanks to the circadian rhythm of some elements in its composition. There are studies showing that breast milk contains high levels of cortisol and amino acids that promote activity during the day, while night milk has high levels of melatonin and tryptophan, and micronutrients vary throughout the day. A better understanding of the circadian rhythm displayed by the elements in the composition of breast milk is important for improving maternal and infant health. Since there are many factors affecting the composition of breast milk, it is recommended that breast milk studies should be done on a country or regional basis, and breastfeeding policies can be developed as a result of the results to be obtained. [ABSTRACT FROM AUTHOR]

The light/dark cycle is the main external cue to synchronize the human biological clock. Modern lifestyles typically lead to less daylight exposure and blunted 24 h-amplitude. We evaluated the association of outdoor daylight exposure (frequency, duration, regularity and shift) with chronotype estimated by sleep phase, regularity of routines, sleep, well-being (WHO-5), and depressive symptoms (PHQ-9), in a sample of 1,095 participants (81.8% female; 87.9% aged 18–49) surveyed online between July and November 2020. We analyzed direct and indirect associations in daylight-mood relationship with chronotype-estimate, routine regularity, and sleep as mediators. Outdoor daylight exposure was associated with WHO-5/PHQ-9 scores in mediation models, with higher total effects when the exposure was every day (β = 4.13 ± 0.53/ β = −3.81 ± 0.67), for more than 4 hours (β = 3.77 ± 0.91/ β = −3.83 ± 1.31) and during the morning (β = 3.41 ± 0.53/ β = −3.74 ± 0.70) in reference to lack of exposure. Chronotype-estimate, routine regularity score, and sleep problems acted as mediators, while social jetlag and sleep duration did not play an important role in this association. This study advanced the understanding of the complex interplay between light exposure, mental health, and individual characteristics of sleep and other routine regularities, and showed the benefits of optimizing daylight exposure to improve mental health. [ABSTRACT FROM AUTHOR]

The study aimed to assess the regularity, intensity, frequency, and period of activities comprising social rhythm and associate them with the functionality of stroke patients. The sample consisted of 73 patients (41 men and 32 women) with a mean age of 60 years (±10). Social rhythm was assessed by Social Rhythm Metric (SRM) and Activity Level Index (ALI). The functionality was evaluated using the International Classification of Functioning, Disability, and Health (ICF). Data were analyzed using Student's t-test, ANOVA, and Chi-square test. The mean SRM was 5.1 ± 0.9, and ALI was 58.3 ± 14.9. Notably, 40% of the patients exhibited both low regularity and low intensity of activities. Six SRM activities, performed with low frequency (going outside, starting work, exercising, snacking, watching other TV programs, and going home), exhibited a tendency to have periods that deviated from the expected 24-hour daily cycle. ICF domains most associated with SRM were: d2-General tasks and demands, d3-Communication, d4-Mobility, d5-Self care, d8-Major life areas, and d9-Community, social and civic life. The results indicated changes in social rhythm with implications for patient functionality. Screening for disruptions in social rhythm could be part of the functional assessment during the rehabilitation process for post-stroke patients. [ABSTRACT FROM AUTHOR]

Current international optical science research focuses on the non-visual effects of lighting on human cognition, mood, and biological rhythms to enhance overall well-being. Nocturnal roadway lighting, in particular, has a substantial impact on drivers' physiological and psychological states, influencing behavior and safety. This study investigates the non-visual effects of correlated color temperature (CCT: 3000K vs. 4000K vs. 5000K) and illuminance levels (20 lx vs. 30 lx) of urban motor vehicle road lighting on driver alertness during various driving tasks. Conducted between 19:00 and 20:30, the experiments utilized a human-vehicle-light simulation platform. EEG (β waves), reaction time, and subjective evaluations using the Karolinska Sleepiness Scale (KSS) were measured. The results indicated that the interaction between CCT and illuminance, as well as between CCT and task type, significantly influenced driver alertness. However, no significant effect of CCT and illuminance on reaction time was observed. The findings suggest that higher illuminance (30 lx) combined with medium CCT (4000K) effectively reduces reaction time. This investigation enriches related research, provides valuable reference for future studies, and enhances understanding of the mechanisms of lighting's influence on driver alertness. Moreover, the findings have significant implications for optimizing the design of urban road lighting. [ABSTRACT FROM AUTHOR]

Background: This study aims to verify the accuracy of item 10 on the energy level of the Short-Form Health Survey (SF-12) in an item screening according to Mood Disorder Questionnaire (MDQ) results, providing a measure of hyper-energy. Methods: Regression techniques were employed in a dataset comprising 4093 records of respondents to test both linear and nonlinear relationships between predictor and outcome variables (energy level and symptoms considered in the MDQ). We examined the relationship of energy level with cases identified using MDQ with a cut-off of 7. Results: Levels of energy, as rated on item 10 of the SF-12, were related to the MDQ score with sensitivity = 0.72 and specificity = 0.70. In linear regression, the associations were stronger with MDQ items on excessive energy or activity, showing a medium effect size and an explained variance of 10% or higher. A greater association was observed for items on excessive energy and activity, as expected, as well as for items concerning self-confidence, sociability, and talkativeness. Conclusions: This result may have implications for the research on risk factors and the pathogenesis of the dysregulation of mood, energy, and social rhythms syndrome (DYMERS), a syndrome that is hypothesized to occur in stressful conditions like those shown under the COVID-19 pandemic. [ABSTRACT FROM AUTHOR]

In this paper, we aim to enhance genetic algorithms (GAs) by integrating a dynamic model based on biological life cycles. This study addresses the challenge of maintaining diversity and adaptability in GAs by incorporating stages of birth, growth, reproduction, and death into the algorithm's framework. We consider an asynchronous execution of life cycle stages to individuals in the population, ensuring a steady-state evolution that preserves high-quality solutions while maintaining diversity. Experimental results demonstrate that the proposed extension outperforms traditional GAs and is as good or better than other well-known and well established algorithms like PSO and EvoSpace in various benchmark problems, particularly regarding convergence speed and solution qu/ality. The study concludes that incorporating biological life-cycle dynamics into GAs enhances their robustness and efficiency, offering a promising direction for future research in evolutionary computation. [ABSTRACT FROM AUTHOR]

Plants possess the remarkable ability to integrate the circadian clock with various signalling pathways, enabling them to quickly detect and react to both external and internal stress signals. However, the interplay between the circadian clock and biological processes in orchestrating responses to environmental stresses remains poorly understood. TOC1, a core component of the plant circadian clock, plays a vital role in maintaining circadian rhythmicity and participating in plant defences. Here, our study reveals a direct interaction between TOC1 and the promoter region of MYB44, a key gene involved in plant defence. TOC1 rhythmically represses MYB44 expression, thereby ensuring elevated MYB44 expression at dawn to help the plant in coping with lowest temperatures during diurnal cycles. Additionally, both TOC1 and MYB44 can be induced by cold stress in an Abscisic acid (ABA)‐dependent and independent manner. TOC1 demonstrates a rapid induction in response to lower temperatures compared to ABA treatment, suggesting timely flexible regulation of TOC1‐MYB44 regulatory module by the circadian clock in ensuring a proper response to diverse stresses and maintaining a balance between normal physiological processes and energy‐consuming stress responses. Our study elucidates the role of TOC1 in effectively modulating expression of MYB44, providing insights into the regulatory network connecting the circadian clock, ABA signalling, and stress‐responsive genes. Summary statement: We present initial evidence that MYB44, a key player in the ABA signalling pathway, is directly targeted by the circadian clock. Additionally, our findings offer a comprehensive understanding of the TOC1‐MYB44 module, elucidating its crucial role under both ABA‐dependent and ABA‐independent conditions during cold stress. [ABSTRACT FROM AUTHOR]

The time of day that we eat is increasingly recognized as contributing as importantly to overall health as the amount or quality of the food we eat. The endogenous circadian clock has evolved to promote intake at optimal times when an organism is intended to be awake and active, but electric lights and abundant food allow eating around the clock with deleterious health outcomes. In this review, we highlight literature pertaining to the effects of food timing on health, beginning with animal models and then translation into human experiments. We emphasize the pitfalls and opportunities that technological advances bring in bettering understanding of eating behaviors and their association with health and disease. There is great promise for restricting the timing of food intake both in clinical interventions and in public health campaigns for improving health via nonpharmacological therapies. [ABSTRACT FROM AUTHOR]

Recent decades have seen substantive changes in reproductive patterns involving decisions whether, when and how to have children. Although time is at the core of transformations of contemporary childbearing, there are few systematic theoretical reflections and empirical studies on reproductive time. Drawing on sociological, feminist and decolonial approaches to time and 40 life story interviews on the transition to motherhood, this article explores the multiple ontologies of time shaping women's reproductive experiences. The findings show that women understand and live reproductive time as determined by God, nature, the clock and technology and often manage convergent and conflicting ontologies of time in negotiating childbearing. These times outline differential spaces for agency and accountability, thus enabling and constraining women's childbearing experiences in particular ways. These findings advance knowledge on the temporal dimension of childbearing, challenge normative assumptions underlying reproductive time and contribute to better understand contemporary changes in the nature of reproduction. [ABSTRACT FROM AUTHOR]

Summary: The well‐established effects of evening preference on diminished well‐being and poorer mental health are usually explained in terms of common genetic bases of eveningness and negative emotionality and/or the discrepancy between biological and social clocks, experienced far more frequently by the Evening‐types. However, recent studies provide evidence for the negative stereotyping of evening chronotypes which may lead to unexpectedly pronounced social stigma and its consequences. The present article provides a seminal empirical analysis of the role of perceived chronotype‐related discrimination in the association between morningness‐eveningness and both positive affect and negative affect. The study was conducted on a gender‐balanced sample of 768 individuals aged between 18 and 56 years who filled measures of morningness‐eveningness, positive and negative affect, as well as a modified version of the Perceived Devaluation Discrimination scale, tentatively labeled Perceived Chronotype‐Related Discrimination scale (https://osf.io/urs8x/), developed to measure the sense of chronotype‐based discrimination. Conducted analyses provided evidence for a positive association between eveningness and perceived discrimination. Moreover, perceived discrimination partly mediated the associations between morningness‐eveningness and both positive affect and negative affect, explaining 18% and 29% of these effects, respectively. Hence, our results provide initial evidence for yet another mechanism through which chronotype may impact emotional functioning, namely the experience of chronotype‐based stigmatisation. [ABSTRACT FROM AUTHOR]

The suprachiasmatic nucleus of the hypothalamus (SCN) houses the central circadian oscillator of mammals. The main neurotransmitters produced in the SCN are γ‐amino‐butyric acid, arginine‐vasopressin (AVP), vasoactive intestinal peptide (VIP), pituitary‐derived adenylate cyclase‐activating peptide (PACAP), prokineticin 2, neuromedin S, and gastrin‐releasing peptide (GRP). Apart from these, catecholamines and their receptors were detected in the SCN as well. In this study, we confirmed the presence of β‐adrenergic receptors in SCN and a mouse SCN‐derived immortalized cell line by immunohistochemical, immuno‐cytochemical, and pharmacological techniques. We then characterized the effects of β‐adrenergic agonists and antagonists on cAMP‐regulated element (CRE) signaling. Moreover, we investigated the interaction of β‐adrenergic signaling with substances influencing parallel signaling pathways. Our findings have potential implications on the role of stress (elevated adrenaline) on the biological clock and may explain some of the side effects of β‐blockers applied as anti‐hypertensive drugs. [ABSTRACT FROM AUTHOR]

Nitrogen (N) bioavailability affects phytoplankton growth and primary production in the aquatic environment. N bioavailability is partly determined by biological N cycling processes that either transform N species or remove fixed N. Reliable estimates of their kinetic parameters can help understand the distribution of N cycling processes. However, available estimates of kinetic parameters are often derived from microbial isolates and may not be representative of the natural environment. Observations are particularly lacking in estuarine and coastal waters. We conducted isotope tracer addition incubations to evaluate substrate affinities of nitrification, denitrification and anammox in the Chesapeake Bay water column. The half‐saturation constant for ammonia oxidation ranged from 0.38 to 0.75 μM ammonium, substantially higher than observed in the open oceans. Half‐saturation constants for denitrification—0.92–1.86 μM nitrite or 1.15 μM nitrate—were within the lower end or less than those reported for other aquatic environments and for denitrifier isolates. Interestingly, water column denitrification potential was comparable to that of sedimentary denitrification, highlighting the contribution of the water column to N removal during anoxia. Mostly undetectable anammox rates prevented us from deriving the half‐saturation constants, suggesting a low affinity of anammox. Using these substrate kinetics, we were able to predict in situ N cycling rates and explain the vertical distribution of N nutrient concentrations. Our newly derived substrate kinetics parameters can be useful for improving model representation of N nutrient dynamics in estuarine and coastal waters, which is critical for assessing the ecosystem productivity and function. [ABSTRACT FROM AUTHOR]

The Institute of Physiology of the Czech Academy of Sciences (CAS) has been involved in the field of chronobiology, i.e., in research on temporal regulation of physiological processes, since 1970. The review describes the first 35 years of the research mostly on the effect of light and daylength, i.e., photoperiod, on entrainment or resetting of the pineal rhythm in melatonin production and of intrinsic rhythms in the central biological clock. This clock controls pineal and other circadian rhythms and is located in the suprachiasmatic nuclei (SCN) of the hypothalamus. During the early chronobiological research, many original findings have been reported, e.g. on mechanisms of resetting of the pineal rhythm in melatonin production by short light pulses or by long exposures of animals to light at night, on modulation of the nocturnal melatonin production by the photoperiod or on the presence of high affinity melatonin binding sites in the SCN. The first evidence was given that the photoperiod modulates functional properties of the SCN and hence the SCN not only controls the daily programme of the organism but it may serve also as a calendar measuring the time of a year. During all the years, the chronobiological community has started to talk about “the Czech school of chronobiology”. At present, the today´s Laboratory of Biological Rhythms of the Institute of Physiology CAS continues in the chronobiological research and the studies have been extended to the entire circadian timekeeping system in mammals with focus on its ontogenesis, entrainment mechanisms and circadian regulation of physiological functions. [ABSTRACT FROM AUTHOR]

The subject of this article are patients with ankylosing spondylitis and the possibilities of improving the control of morning pain and stiffness characteristic of the disease by applying the principles of chronopharmacology. Chronopharmacology uses knowledge of biological rhythms to develop an optimal pharmacotherapeutic plan. The aim was to study and summarize the modern medical literature on the subject by means of the methods of analysis of the information obtained by keywords in specialized electronic medical databases. In conclusion, it can be said that the results of the study of the available literature show the importance of applying the principles of chronopharmacology to achieve optimal pain control, manage morning stiffness and improve therapeutic results in patients with ankylosing spondylitis. [ABSTRACT FROM AUTHOR]

Abstract Robust circadian rhythms are essential for optimal health. The central circadian clock controls temperature rhythms, which are known to organize the timing of peripheral circadian rhythms in rodents. In humans, however, it is unknown whether temperature rhythms relate to the organization of circadian rhythms throughout the body. We assessed core body temperature amplitude and the rhythmicity of 929 blood plasma metabolites across a 40-h constant routine protocol, controlling for behavioral and environmental factors that mask endogenous temperature rhythms, in 23 healthy individuals (mean [± SD] age = 25.4 ± 5.7 years, 5 women). Valid core body temperature data were available in 17/23 (mean [± SD] age = 25.6 ± 6.3 years, 1 woman). Individuals with higher core body temperature amplitude had a greater number of metabolites exhibiting circadian rhythms (R2 = 0.37, p = .009). Higher core body temperature amplitude was also associated with less variability in the free-fitted periods of metabolite rhythms within an individual (R2 = 0.47, p = .002). These findings indicate that a more robust central circadian clock is associated with greater organization of circadian metabolite rhythms in humans. Metabolite rhythms may therefore provide a window into the strength of the central circadian clock.

The present study has been designed to establish the thermal profile of complete life cycle of the Antheraea assamensis (muga) silkworms starting from the eggs to the moth. The current study also concurrently addresses the applicability of infrared thermography (IRT) to detect muga larvae infected with pebrine. Because of its non-contact advantage, IRT imaging can be successfully manoeuvred to reduce the risk of spreading infections and ultimately lead to increased silk production. The images and data obtained by the non-invasive IRT technology can be implemented, analysed and translated into deep learning algorithm-based machine learning called 'smart data', which can be fine-tuned to develop an artificial intelligence (AI) and decision support system (DSS) for the management and monitoring of silkworms in their entire life progression. Hence, this will boost their productivity, which will further revolutionize their yearly production and convey attractive revenues in the global silk picturesque. [ABSTRACT FROM AUTHOR]

Robust circadian rhythms are essential for optimal health. The central circadian clock controls temperature rhythms, which are known to organize the timing of peripheral circadian rhythms in rodents. In humans, however, it is unknown whether temperature rhythms relate to the organization of circadian rhythms throughout the body. We assessed core body temperature amplitude and the rhythmicity of 929 blood plasma metabolites across a 40-h constant routine protocol, controlling for behavioral and environmental factors that mask endogenous temperature rhythms, in 23 healthy individuals (mean [± SD] age = 25.4 ± 5.7 years, 5 women). Valid core body temperature data were available in 17/23 (mean [± SD] age = 25.6 ± 6.3 years, 1 woman). Individuals with higher core body temperature amplitude had a greater number of metabolites exhibiting circadian rhythms (R2 = 0.37, p =.009). Higher core body temperature amplitude was also associated with less variability in the free-fitted periods of metabolite rhythms within an individual (R2 = 0.47, p =.002). These findings indicate that a more robust central circadian clock is associated with greater organization of circadian metabolite rhythms in humans. Metabolite rhythms may therefore provide a window into the strength of the central circadian clock. [ABSTRACT FROM AUTHOR]

The mammalian circadian timing system has a hierarchical architecture, with a central pacemaker located in the brain's suprachiasmatic nucleus orchestrating rhythms in behaviour and physiology. In cooperation with environmental cycles, it synchronizes the phases of peripheral oscillators operating in most cells of the body. Even cells kept in tissue culture harbour self‐sustained and cell‐autonomous circadian clocks that keep ticking throughout their lifespan. The master pacemaker in the suprachiasmatic nucleus is synchronized primarily by light–dark cycles, whereas peripheral oscillators are phase entrained by a multitude of systemic signalling pathways. These include pathways depending on feeding–fasting cycles, cellular actin polymerization dynamics, endocrine rhythms and, surprisingly, body temperature oscillations. Using tissue culture and murine models, Steve Brown was the first one to demonstrate that shallow rhythms of mammalian body temperature are timing cues (zeitgebers) for peripheral circadian clocks. [ABSTRACT FROM AUTHOR]

Electroencephalography (EEG) wearable devices are particularly suitable for monitoring a subject's engagement while performing daily cognitive tasks. EEG information provided by wearable devices varies with the location of the electrodes, the suitable location of which can be obtained using standard multi-channel EEG recorders. Cognitive engagement can be assessed during working memory (WM) tasks, testing the mental ability to process information over a short period of time. WM could be impaired in patients with epilepsy. This study aims to evaluate the cognitive engagement of nine patients with epilepsy, coming from a public dataset by Boran et al., during a verbal WM task and to identify the most suitable location of the electrodes for this purpose. Cognitive engagement was evaluated by computing 37 engagement indexes based on the ratio of two or more EEG rhythms assessed by their spectral power. Results show that involvement index trends follow changes in cognitive engagement elicited by the WM task, and, overall, most changes appear most pronounced in the frontal regions, as observed in healthy subjects. Therefore, involvement indexes can reflect cognitive status changes, and frontal regions seem to be the ones to focus on when designing a wearable mental involvement monitoring EEG system, both in physiological and epileptic conditions. [ABSTRACT FROM AUTHOR]

Shift work is a recognized work pattern for nurses worldwide. The disruption of shift workers' biological clocks usually leads to sleep disorders and affects their awareness at work. Eveningness and occupational stress might be effective in causing burnout syndrome. Therefore, this study aimed to evaluate the chronotype, job burnout and perceived stress among Chinese tertiary hospital nurses, and understand the predictors of circadian rhythm in this group. Between July and September 2020, 23 hospitals were randomly selected from 113 tertiary hospitals in Hunan Province. Twenty-five percent of the nurses working in each hospital were targeted for selection. 28.1% and 17.6% of nurses reported eveningness type and morningness type, respectively. The scores for emotional exhaustion, depersonalization, and perceived stress of eveningness nurses were higher than those of morningness counterparts. Eveningness nurses also reported a lower sense of personal accomplishment. Risk factors of eveningness included being under 30 years old, never exercising, having the stressors of late-night shifts and career development, higher levels of emotional exhaustion, sleep latency, sleep duration, and hypnotic use. Shifts may be unavoidable for nurses, nevertheless, understanding the predictors and related factors of chronotype for nurses is necessary for nursing educators and managers to develop a reasonable shift system and appropriate measures to assist nurses in adjusting their work. [ABSTRACT FROM AUTHOR]

This study examined the psychometric properties and longitudinal changes of the self-reporting Traditional Chinese version of Biological Rhythms Interview for Assessment in Neuropsychiatry (C-BRIAN-SR) among healthy controls (HC) and patients with major depressive episode (MDE). Eighty patients with a current MDE and 80 HC were recruited. Assessments were repeated after two weeks in HC, and upon the discharge of MDE patients to examine the prospective changes upon remission of depression. The C-BRIAN-SR score was significantly higher in the MDE than HC group. The concurrent validity was supported by a positive correlation between scores of C-BRIAN-SR, Insomnia Severity Index and the Hospital Anxiety Depression Scale. C-BRIAN-SR negatively correlated MEQ in the MDE group (r =.30, p = 0.009), suggesting higher rhythm disturbances were associated with a tendency toward eveningness. A moderate test-retest reliability was found (r =.61, p < 0.001). A cut-off of 38.5 distinguished MDE subjects from HC with 82.9% of sensitivity and 81.0% of specificity. C-BRIAN-SR score normalized in remitted MDE patients but remained higher in the non-remitted. The C-BRIAN-SR is a valid and reliable scale for measuring the biological rhythms and may assist in the screening of patients with MDE. [ABSTRACT FROM AUTHOR]

Most organisms synchronize to an approximately 24-hour (circadian) rhythm. This study introduces a novel deep learning-powered video tracking method to assess the stability, fragmentation, robustness and synchronization of activity rhythms in Xyrichtys novacula. Experimental X. novacula were distributed into three groups and monitored for synchronization to a 14/10 hours of light/dark to assess acclimation to laboratory conditions. Group GP7 acclimated for 1 week and was tested from days 7 to 14, GP14 acclimated for 14 days and was tested from days 14 to 21 and GP21 acclimated for 21 days and was tested from days 21 to 28. Telemetry data from individuals in the wild depicted their natural behavior. Wild fish displayed a robust and minimally fragmented rhythm, entrained to the natural photoperiod. Under laboratory conditions, differences in activity levels were observed between light and dark phases. However, no differences were observed in activity rhythm metrics among laboratory groups related to acclimation period. Notably, longer acclimation (GP14 and GP21) led to a larger proportion of individuals displaying rhythm synchronization with the imposed photoperiod. Our work introduces a novel approach for monitoring biological rhythms in laboratory conditions, employing a specifically engineered video tracking system based on deep learning, adaptable for other species. [ABSTRACT FROM AUTHOR]

David S. Saunders was an outstanding scientist, who devoted his life to his family and to insects. He has made many fundamental contributions to our understanding of how insects reproduce and adapt their reproduction and development to the seasonal changes on our planet. Most importantly, he was a pioneer in demonstrating the role of the circadian clock in insect photoperiodic time measurement, first in the jewel wasp Nasonia vitripennis, and later in varies species of flies. His books on biological rhythms and insect clocks are important undergraduate, graduate and research reference literature. David was also a brilliant teacher and mentor and played a major role in establishing and teaching a series of successful Erasmus-funded Chronobiology Summer Schools in Europe. He leaves behind a legacy, both professionally and personally. [ABSTRACT FROM AUTHOR]

Annual rhythms are observed in living organisms with numerous ecological implications. In the zooplanktonic copepod Calanus finmarchicus, such rhythms are crucial regarding its phenology, body lipid accumulation, and global carbon storage. Climate change drives annual biological rhythms out of phase with the prevailing environmental conditions with yet unknown but potentially catastrophic consequences. However, the molecular dynamics underlying phenology are still poorly described. In a rhythmic analysis of C. finmarchicus annual gene expression, results reveal that more than 90% of the transcriptome shows significant annual rhythms, with abrupt and dramatic upheaval between the active and diapause life cycle states. This work explores the implication of the circadian clock in the annual timing, which may control epigenetic mechanisms to profoundly modulate gene expression in response to calendar time. Results also suggest an increased light sensitivity during diapause that would ensure the photoperiodic entrainment of the endogenous annual clock. [ABSTRACT FROM AUTHOR]

Simple Summary: Bladder cancer, an age-related disorder, primarily affects individuals aged 65 and older. Accelerated biological aging, which is linked to increased cancer susceptibility, raises questions about its association with bladder cancer risk. We evaluated four widely recognized epigenetic clocks—HannumAge, HorvathAge, GrimAge, and PhenoAge—for their relationship with bladder cancer risk in a large case–control study. By leveraging genome-wide-association study (GWAS) data and constructing weighted genetic risk scores (GRS), we found that higher HannumAge and HorvathAge GRS were significantly associated with increased bladder cancer risk (OR = 1.69, 95% CI: 1.44–1.98, p = 1.56 × 10−10 and OR = 1.09, 95% CI: 1.00–1.19, p = 0.04, respectively). Mendelian randomization (MR) analysis using inverse-variance weighting (IVW) confirmed these associations, which was also supported by sensitivity analyses. However, GrimAge and PhenoAge showed no significant association with bladder cancer risks. Our findings highlighted the link between accelerated biological aging and elevated bladder cancer risk. Bladder cancer is an age-related disease, with over three-quarters of cases occurring in individuals aged 65 years and older. Accelerated biological aging has been linked to elevated cancer risks. Epigenetic clocks serve as excellent predictors of biological age, yet it remains unclear whether they are associated with bladder cancer risk. In this large case–control study, we assessed the associations between four well-established epigenetic clocks—HannumAge, HorvathAge, GrimAge, and PhenoAge—and bladder cancer risk. Utilizing single nucleotide polymorphisms (SNPs), which were identified in a genome-wide association study (GWAS), linked to these clocks as instruments, we constructed a weighted genetic risk score (GRS) for each clock. We discovered that higher HannumAge and HorvathAge GRS were significantly associated with increased bladder cancer risk (OR = 1.69 per SD increase, 95% CI, 1.44–1.98, p = 1.56 × 10−10 and OR = 1.09 per SD increase, 95% CI, 1.00–1.19, p = 0.04, respectively). Employing a summary statistics-based Mendelian randomization (MR) method, inverse-variance weighting (IVW), we found consistent risk estimates for bladder cancer with both HannumAge and HorvathAge. Sensitivity analyses using weighted median analysis and MR-Egger regression further supported the validity of the IVW method. However, GrimAge and PhenoAge were not associated with bladder cancer risk. In conclusion, our data provide the first evidence that accelerated biological aging is associated with elevated bladder cancer risk. [ABSTRACT FROM AUTHOR]

The restoration of longitudinal connectivity in rivers allows fish to colonise new habitats. However, there is a lack of information regarding the behaviour of fish when they colonise the newly opened river stretch. We used manual radiotelemetry to tracked individuals belonging to four species (trout, nase, grayling and barbel) after their release upstream of two obstacles in the Amblève River. We observed a diversity of movement behaviours and habitats used among the studied species. All the species used potential spawning habitats with distances travelled upstream reaching 2.4 km for the grayling, 7.0 km for the barbel, 16.9 km for the nase and 18.0 km for the trout, which also use tributaries and sub‐tributaries of the Amblève River. Post‐reproduction downstream behaviours were observed in all species, but this was made difficult by the absence of downstream migration devices at dams that forced fish to seek alternative habitats. Our study suggested that allowing fish to move upstream with fishways is beneficial as the species succeeded in reaching spawning grounds, but a holistic approach combined with the installations of devices or an opening of gates to allow post‐reproduction downstream migrations would allow them to completely accomplish their biological cycle. [ABSTRACT FROM AUTHOR]

The article is a review of a book titled "Studies on Tantra in Bengal and Eastern India" edited by Madhu Khanna. The book explores the Tantric traditions of Eastern India, with a focus on the concept of Śakti in its various aspects. The volume is divided into three parts, covering topics such as syncretism between Śākta and Vaiṣṇava traditions, the Śākta Pīṭhas (pilgrimage sites), and Śākta theology. The articles in the book provide case studies and specific instances of Tantric traditions in the region. The reviewer notes that the book is a valuable contribution to Tantric studies and may be of interest to scholars in various fields. However, they also mention some typos in the volume. [Extracted from the article]

Diurnal rhythms in physiological functions contribute to homeostasis in many organisms. Although relationships between molecular biology and diurnal rhythms have been well studied in model organisms like higher plants, those in harmful algal bloom species are poorly understood. Here we measured several physiological parameters and the expression patterns of photosynthesis-related and antioxidant-enzyme genes in the Chattonella marina complex to understand the biological meaning of diurnal rhythm. Under a light–dark cycle, Fv/Fm and expression of psbA, psbD, and 2-Cys prx showed significant increases in the light and decreases during the dark. These rhythms remained even under continuous dark conditions. DCMU suppressed the induction of psbA, psbD, and 2-Cys prx expression under both light regimes. Oxidative stress levels and H2O2 scavenging activities were relatively stable, and there was no significant correlation between H2O2 scavenging activities and antioxidant-enzyme gene expression. These results indicate that the Chattonella marina complex has developed mechanisms for efficient photosynthetic energy production in the light. Our results showed that this species has a diurnal rhythm and a biological clock. These phenomena are thought to contribute to the efficiency of physiological activities centered on photosynthesis and cell growth related to the diurnal vertical movement of this species. [ABSTRACT FROM AUTHOR]

The advent of artificial lighting, particularly during the evening and night, has significantly altered the predictable daily light and dark cycles in recent times. Altered light environments disrupt the biological clock and negatively impact mood and cognition. Although adolescents commonly experience chronic changes in light/dark cycles, our understanding of how the adolescents’ brain adapts to altered light environments remains limited. Here, we investigated the impact of chronic light cycle disruption (LCD) during adolescence, exposing adolescent mice to 19  h of light and 5  h of darkness for 5  days and 12  L:12D for 2  days per week (LCD group) for 4  weeks. We showed that LCD exposure did not affect circadian locomotor activity but impaired memory and increased avoidance response in adolescent mice. Clock gene expression and neuronal activity rhythms analysis revealed that LCD disrupted local molecular clock and neuronal activity in the dentate gyrus (DG) and in the medial amygdala (MeA) but not in the circadian pacemaker (SCN). In addition, we characterized the photoresponsiveness of the MeA and showed that somatostatin neurons are affected by acute and chronic aberrant light exposure during adolescence. Our research provides new evidence highlighting the potential consequences of altered light environments during pubertal development on neuronal physiology and behaviors. [ABSTRACT FROM AUTHOR]