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Simple Summary: Patients with breast cancer frequently complaint from insomnia difficulties that can affect quality of life and cancer progression. Such difficulties may result from rest-activity (i.e., 24 h alternation of sleep and wake) rhythm alterations consistently reported in this pathology. Currently proposed approaches to counter insomnia difficulties in patients with breast cancer have positive effects only on sleep complaints and well-being. Moreover, such approaches may be difficult to implement shortly after chemotherapy. Innovatively, vestibular stimulation would be particularly suited to tackling insomnia symptoms in patients with breast cancer. Indeed, recent reports have shown that vestibular stimulation could improve rest-activity rhythm and sleep in healthy volunteers. This perspective paper aims to support the evidence of using vestibular stimulation to improve rest-activity rhythms and reduce insomnia symptoms in patients with BC, with beneficial effects on quality of life and, potentially, survival. Insomnia symptoms are common among patients with breast cancer (BC; 20–70%) and are predictors of cancer progression and quality of life. Studies have highlighted sleep structure modifications, including increased awakenings and reduced sleep efficiency and total sleep time. Such modifications may result from circadian rhythm alterations consistently reported in this pathology and known as carcinogenic factors, including lower melatonin levels, a flattened diurnal cortisol pattern, and lower rest-activity rhythm amplitude and robustness. Cognitive behavioral therapy and physical activity are the most commonly used non-pharmacological interventions to counter insomnia difficulties in patients with BC. However, their effects on sleep structure remain unclear. Moreover, such approaches may be difficult to implement shortly after chemotherapy. Innovatively, vestibular stimulation would be particularly suited to tackling insomnia symptoms. Indeed, recent reports have shown that vestibular stimulation could resynchronize circadian rhythms and improve deep sleep in healthy volunteers. Moreover, vestibular dysfunction has been reported following chemotherapy. This perspective paper aims to support the evidence of using galvanic vestibular stimulation to resynchronize circadian rhythms and reduce insomnia symptoms in patients with BC, with beneficial effects on quality of life and, potentially, survival. [ABSTRACT FROM AUTHOR]

They describe the structure of the MRN Complex and its function in double-strand break (DSB) repair and analyze the different germline alterations of the MRN complex genes in autosomal recessive syndromes, as well as the association between heterozygous germline alterations in these genes and cancer predisposition. In the rapidly evolving landscape of molecular genetics and genomics, this Special Issue brings together a collection of insightful review articles that delve into the forefront of scientific exploration. The authors also propose a possible explanation of the discrepancies in the published results of the effects of the OXTR gene polymorphisms and methylation on different diseases [[2]]. [Extracted from the article]

Circadian rhythms are internal regulatory processes controlled by molecular clocks present in essentially every mammalian organ that temporally regulate major physiological functions. In the cardiovascular system, the circadian clock governs heart rate, blood pressure, cardiac metabolism, contractility, and coagulation. Recent experimental and clinical studies highlight the possible importance of circadian rhythms in the pathophysiology, outcome, or treatment success of cardiovascular disease, including ischaemic heart disease. Disturbances in circadian rhythms are associated with increased cardiovascular risk and worsen outcome. Therefore, it is important to consider circadian rhythms as a key research parameter to better understand cardiac physiology/pathology, and to improve the chances of translation and efficacy of cardiac therapies, including those for ischaemic heart disease. The aim of this Position Paper by the European Society of Cardiology Working Group Cellular Biology of the Heart is to highlight key aspects of circadian rhythms to consider for improvement of preclinical and translational studies related to ischaemic heart disease and cardioprotection. Applying these considerations to future studies may increase the potential for better translation of new treatments into successful clinical outcomes. [ABSTRACT FROM AUTHOR]

Circadian rhythms in social insects are highly plastic and are modulated by multiple factors. In addition, complex behaviors such as sun-compass orientation and time learning are clearly regulated by the circadian system in these organisms. Despite these unique features of social insect clocks, the mechanisms as well as the functional and evolutionary relevance of these traits remain largely unknown. Here we show a modification of the Drosophila activity monitoring (DAM) system that allowed us to measure locomotor rhythms of the honey bee, Apis mellifera (three variants; gAHB, carnica and caucasica), and two paper wasps (Polistes crinitus and Mischocyttarus phthisicus). A side-by-side comparison of the endogenous period under constant darkness (free-running period) led us to the realization that these social insects exhibit significant deviations from the Earth's 24 h rotational period as well as a large degree of inter-individual variation compared with Drosophila. Experiments at different temperatures, using honey bees as a model, revealed that testing the endogenous rhythm at 35°C, which is the hive's core temperature, results in average periods closer to 24 h compared with 25°C (23.8 h at 35°C versus 22.7 h at 25°C). This finding suggests that the degree of tuning of circadian temperature compensation varies among different organisms. We expect that the commercial availability, cost-effectiveness and integrated nature of this monitoring system will facilitate the growth of the circadian field in these social insects and catalyze our understanding of the mechanisms as well as the functional and evolutionary relevance of circadian rhythms. [ABSTRACT FROM AUTHOR]

Individuals’ variation in their preference for the daily timing of sleep and wakefulness is known as chronotype. This study aims to examine the reliability and validity of the Chinese version of the Owl and Lark Questionnaire (OLQ; also known as the Horne and Östberg Morningness-Eveningness Questionnaire), which was developed by Horne and Östberg in 1976 and is still today the most frequently used self-evaluation instrument for chronotype. Two selfadministration methods for the Chinese OLQ were studied. The paper and pencil version was studied in university students aged between 18 and 28 years and showed an internal consistency Cronbach’s alpha value of .7 (N = 213) and a one-month-interval test-retest reliability value of .71 (N = 28). The internet version was administered in general adults aged between 18 and 36 years and showed a Cronbach’s alpha value of .75 (N = 660) and a test-retest reliability value of .61 (n = 24) with varying test-retest intervals of 120 ~ 339 days. The OLQ scores of both the versions were negatively correlated with the mean daily bedtime and getup time, i.e., the higher the score (denoting greater circadian preference as a morning type), the earlier the bedtime and getup time. Compared to the morning type and intermediate type, the evening type had the greatest value for the difference in getup time between weekday and weekend and longest sleep duration during the weekend. Age positively and daytime sleepiness negatively correlated to morningness in the internet group. However, sex differences in OLQ scores were not found. Taken together, the results of this study support that both the paper and internet versions of the Chinese OLQ are of good reliability and validity for assessing the phase preference of individuals. [ABSTRACT FROM AUTHOR]

Among the scientific resources that Colin Pittendrigh passed on to his colleagues after his death in 1996 were two unpublished papers. These manuscripts, developed first in the mid-1960s and continually updated and refined through the late 1970s, centered on the development and experimental exploration of a model of circadian entrainment combining aspects of the well-known parametric (continuous) and nonparametric (discrete) models of entrainment. These texts reveal the experimental work surrounding Pittendrigh’s determination of the limits of entrainment and the explanation of the bistability phenomenon. These manuscripts are being made publicly available in their final format (February 1978) as supplementary material to this introduction. [ABSTRACT FROM AUTHOR]

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

Bibliometric indices are a widely used measure of research impact. The aim of the current study was to identify and characterise the top one hundred most-cited research articles in the topic of chronotype research. A search of the Thomson Reuters Web of Science database returned 974 eligible articles (published between 1990 and 2016). Citations for the 100 most-cited articles ranged between 438 and 29. The most represented journal was Chronobiology International (n = 30). Nearly 50% of articles originated in Germany and the U.S. The bibliometrics reported identify key publications and provide insight into trends within the topic of chronotype research. [ABSTRACT FROM AUTHOR]

Two significant benefits derived from reading and discussing classic scientific papers in undergraduate biology courses are 1) providing students with the realistic perspective that science is an ongoing process (rather than a set of inarguable facts) and 2) deepening the students' understanding of physiological processes. A classic paper that is useful in both of these regards is by I. E. Lawton and N. B. Schwartz (A circadian rhythm of luteinizing hormone secretion in ovariectomized rats. Am J Physiol 214: 213-217, 1968). The primary objective of the study is to determine whether tonic (pulsatile) secretion of luteinizing hormone (LH) from the pituitary gland exhibits a circadian rhythm. While this hypothesis seems relatively straightforward, its in vivo investigation necessitates an awareness of the multitude of factors, in addition to the circadian clock, that can influence plasma LH levels (and a consideration of how to control for these factors in the experimental design). Furthermore, discussion of the historical context in which the study was conducted (i.e., before the pulsatile nature of LH secretion had been discovered) provides students with the realistic perspective that science is not a set of facts but rather a systematic series of attempts by scientists to understand reality (a perspective that is difficult to convey using a traditional textbook alone). A review of the historical context in which the study was conducted, and a series of discovery learning questions are included to facilitate classroom discussions and to help deepen students' understanding of the complex nature of pituitary hormone regulation. [ABSTRACT FROM AUTHOR]

Recently, research on the circadian rhythm of hypertension has gained popularity. However, few bibliometric analyses have been conducted in this field. In this study, CiteSpace 6.1. R6, VOSviewer 1.6.18, R language (version 4.2.3), R package Bibliometrix (4.1.2), and Microsoft Excel 365 were used to conduct the data mining and knowledge visualization analysis. A total of 1,560 papers from 1,825 institutions in 77 countries were included. Research on the role of circadian rhythms in hypertension is increasing annually. Overall, Chronobiology International published the most literature and Hypertension received the most citations. Ramon Hermida from the Universidade de Vigo in Spain published the most papers and had the most citations. The United States of America and Japan have been the most productive countries. The University of Ferrara, Universidade de Vigo, and the University of California system produced the most publications. Amongst authors, Hermida had the most and longest literature bursts. Keywords such as "chronic kidney disease," "oxidative stress," and "gene expression" have been breakout keywords since 2014. This study revealed the dynamic evolution of research on circadian rhythms in hypertension and provides a knowledge base for researchers. [ABSTRACT FROM AUTHOR]

Sleep and circadian rhythms are closely related to physical and psychosocial well-being. However, sleep and circadian rhythm disruptions are often overlooked in children with cancer, as they are frequently considered temporary side effects of therapy that resolve when treatment ends. Yet, evidence from adult oncology suggests a bidirectional relationship wherein cancer and its treatment disrupt sleep and circadian rhythms, which are associated with negative health outcomes such as poor immune functioning and lower survival rates. A growing body of research demonstrates that sleep problems are prevalent among children with cancer and can persist into survivorship. However, medical and psychosocial outcomes of poor sleep and circadian rhythmicity have not been explored in this context. It is essential to increase our understanding because sleep and circadian rhythms are vital components of health and quality of life. In children without cancer, sleep and circadian disturbances respond well to intervention, suggesting that they may also be modifiable in children with cancer. We present this paper as a call to (a) incorporate sleep or circadian rhythm assessment into pediatric cancer clinical trials, (b) address gaps in understanding the bidirectional relationship between sleep or circadian rhythms and health throughout the cancer trajectory, and (c) integrate sleep and circadian science into oncologic treatment. [ABSTRACT FROM AUTHOR]

Preclinical molecular imaging is a rapidly growing field, where new imaging systems, methods, and biological findings are constantly being developed or discovered. Imaging systems and the associated software usually have multiple options for generating data, which is often overlooked but is essential when reporting the methods used to create and analyze data. Similarly, the ways in which animals are housed, handled, and treated to create physiologically based data must be well described in order that the findings be relevant, useful, and reproducible. There are frequently new developments for metabolic imaging methods. Thus, specific reporting requirements are difficult to establish; however, it remains essential to adequately report how the data have been collected, processed, and analyzed. To assist with future manuscript submissions, this article aims to provide guidelines of what details to report for several of the most common imaging modalities. Examples are provided in an attempt to give comprehensive, succinct descriptions of the essential items to report about the experimental process. [ABSTRACT FROM AUTHOR]

Two moments from the clinical narrative under discussion are used to highlight the critical impact of attention to timing not in terms of when and what to say, but rather as a an ongoing source of emotional meaning emerging on implicit dimensions of rhythm and affective tone occurring in the clinical interaction. Meanings having to do with different forms of power including fear of psychic annihilation, agency, and aggression expressed within sado-masochistic dynamics are demonstrated to be scaffolded and coming into formation on these implicit levels. Alternatively, Merleu-Ponty's concept of Urdoxa as a grip on context is introduced to highlight how the analyst's use of timing to violate an expectation for nonresponsiveness or impingement creates an experience of distance between enactment and reflection, allowing space for re-membering as a form of representation. Here the creation of space through timing serves not just a representational function, but also a way for affective self and interactive regulation to emerge in an interaction as scaffolding for experiences of predictability (i.e., continuity and coherence) and vitality in self and other. [ABSTRACT FROM PUBLISHER]

The article offers information on the XXVI INTERNATIONAL CONGRESS OF PSYCHOLOGY as of June 1996. Topics discussed include stereotyping the outgroup: effects of perceived ability on estimated task performance with similar and different others; examination of complex behaviors using genetic strategies; and analysis of circadian behavioral rhythms using genetically altered mice.

The article presents abstracts on psychological topics which include biofeedback, social interaction and electroencephalography.

A time‐varying lighting regime was formulated based on the action spectrum of the circadian and photopic lights. Using LED panels, the regime was implemented, tested and evaluated in classroom environment. The circadian to photopic ratio C/P was identified as one of the key parameters along with standard photometric and spectrometric quantities. The circadian rhythm of the human body as decomposed into time intervals of the day. By the continuous monitoring of the light output from the LED panels, we obtained instantaneous values and variation in the parameters, such as luminous flux, correlated color temperatures, color rendering indices, luminous efficiency and CS value. Based on these measurement data, we derived the variation of color temperature versus that of black body radiation and that of the color coordinates of the sun light. we also calculated the circadian stimulus curve and found it consistent with the one suggested by Mark Rea et al. [ABSTRACT FROM AUTHOR]

Antony N. Dodd is a plant scientist who is interested in chronobiology and circadian rhythms. He was inspired to study plant biology after attending lectures by Howard Griffiths, which showed how biochemical processes in plants could be studied over 24-hour cycles. Dodd pursued a career in research because he was fascinated by the control of daily cycles of Crassulacean acid metabolism in plants. He is motivated by the social element of science and the interactions with his research group and colleagues. Dodd provides advice for scientists, such as investing time to get things right, not only chasing big papers, and being collegial. He also discusses his favorite New Phytologist papers, which explore the use of chemical biology to study circadian rhythms in plants. Dodd mentions two favorite plant species, Agave americana and Aegagropila linnaei, and their significance in his research. [Extracted from the article]

The article features an interview with Emmet Francis, the first author of a paper titled "Computational modeling establishes mechanotransduction as a potent modulator of the mammalian circadian clock" published in the Journal of Cell Science. The paper discusses the integration of a cell's response to mechanical cues with its intrinsic circadian clock using a mathematical model. The simulations show that increased mechanical activation can alter the period and amplitude of circadian oscillations and even eliminate them in certain cases. The findings have implications for diseases associated with changes in cell and tissue mechanical properties and tissues that experience strain. [Extracted from the article]

The long-term effect of mediated minimal behavioral intervention on poor sleepers was examined. Through comparison of the baseline and a 1-year follow-up questionnaire of 36 subjects who participated in a self-help sleep-behavior modification program, total sleep time was increased by 0.49 h ( P < 0.05), sleep efficiency was improved by 6.1% ( P < 0.05), and both sleep latency and time-in-bed after sleep offset tended to decrease. As for sleep-related behaviors, oversleeping in the weekends improved significantly ( P < 0.05), dinner time, relaxation with bath, and regular exercise tended to also improve ( P < 0.1). These results suggest that a simple behavioral approach produced long-term effects in the improvement of sleep quality. [ABSTRACT FROM AUTHOR]

The average bedtime and sleep duration of Japanese students aged 12–18 years was later and shorter, respectively, by 1 h compared with those of Italian students. Japanese students aged 12–15 years were predominantly more evening-typed than Italian students, while there were no significant differences in the morningness-eveningness (M-E) scores between students aged 16–18 years in the two countries. The bedtime of approximately 70% of Italian students was fixed by parents during their childhood, whereas the bedtime of only 40% of Japanese students was fixed by their parents. Current bedtime fixation made the students (both Japanese and Italian) aged 12–15 years more morning-typed, while it had no effects on the M-E scores of students 16–18 years. [ABSTRACT FROM AUTHOR]

Introduction and aim. Sleep is a functional state of the CNS, which appears cyclically in the circadian rhythm. The amount and quality of sleep has a strong impact on mental health, cognitive function (like learning or concentration) and libido. This study aims to show what is the knowledge about the importance of sleep among young people and the impact of sleep deprivation on various aspects of their lives. What's more, we want to show how to improve sleep quality. Material and methods. A literature review was performed by analyzing randomized controlled trials and systematic reviews from PubMed/MEDLINE published in the last five years. For the literature search, following keywords: Sleep quality*, mental health* and libido* were used. Regardless of this, the authors conducted a survey (23 questions) in 555 people (including 404 women and 151 men) aged 15-30. Analysis of literature. Literature review has shown decreased amount of sleep leads to increase susceptibility to irritability, lowered mood, cognitive functions and libido. Also 88% of our respondents noticed an increase in irritability with reduced sleep. Respondents rated their mood higher on days when they slept more, 44% of respondents indicated a decrease in libido with a reduced amount of sleep (34% of people had no opinion). Survey research also shown that 99% of respondents believe that sleep has a significant impact on health. Conclusion. Sleep has a significant impact on various aspects of life. The awareness of young people about the importance of sleep is at a high level, however, this knowledge is not always practical. Therefore, young people should be made aware of the importance of sleep hygiene. [ABSTRACT FROM AUTHOR]

Present Study analysis 201 publications (1972-2008) of Nobel laureate Jeffrey C Hall, an American eminent scientist in geneticist. His publications received 18,896 citations and first paper was reported in Scopus in 1972, subsequently, he published 200 research papers in various journals. The collaboration coefficient of scientist is 0.89 and forty-three (43) are two authored publications, 22 are single authored, scientist has authored highest publication in decade III (1990-1999) with 81(40.30%) publications. The paper entitled "A pdf neuropeptide gene mutation and ablation of PDF neurons each cause severe abnormalities of behavioral circadian rhythms in Drosophila" published in 'Cell' journal in 2000 has been cited highest 632 times with ranked 1 among all his publications. Study reveals out of 201 publications 193 (96.02%) papers are obtained all 18896 citations, and top 20(9.95%) publications are obtained 7566(40.04%) citations, and cited more than 200 times, scientist preferred 50 channel of communications are used to publish his research output, most publications 28(13.93%) were published in 'Genetics' (IF: 4.556) journal. [ABSTRACT FROM AUTHOR]

Light is the major synchronizer of circadian rhythms to local time on earth. Light can also elicit an acute alerting effect on humans. This paper discusses lighting characteristics that affect the circadian system and how self-luminous displays can be used to promote entrainment and alertness. [ABSTRACT FROM AUTHOR]

Three shelf sea models are compared against observed surface temperature and salinity in Liverpool Bay and the Irish Sea: a 7 km NEMO model, and 12 km and 1.8km POLCOMS models. Each model is run with two different surface forcing datasets of different resolutions. Comparisons with a variety of observations from the Liverpool Bay Coastal Observatory show that increasing the surface forcing resolution improves the modelled surface temperature in all the models, in particular reducing the summer warm bias and winter cool bias. The response of surface salinity is more varied with improvements in some areas and deterioration in others. The 7km NEMO model performs as well as the 1.8km POLCOMS model when measured by overall skill scores although the sources of error in the models are different. NEMO is too weakly stratified in Liverpool Bay, whereas POLCOMS is too strongly stratified. The horizontal salinity gradient, which is too strong in POLCOMS, is better reproduced by NEMO which uses a more diffusive horizontal advection scheme. This leads to improved semi-diurnal variability in salinity in NEMO at a mooring site located in the Liverpool Bay ROFI area. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Tissue Engineering Research / Zhongguo Zuzhi Gongcheng Yanjiu is the property of Chinese Journal of Tissue Engineering Research and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Circadian rhythm is ubiquitous in nature. Circadian clock genes such as Bmal1 and Clock form a multi-level transcription-translation feedback network, and regulate a variety of physiological and pathological processes, including bone and cartilage metabolism. Deletion of the core clock gene Bmal1 leads to pathological bone alterations, while the phenotypes are not consistent. Studies have shown that multiple signaling pathways are involved in the process of Bmal1 regulating bone and cartilage metabolism, but the exact regulatory mechanisms remain unclear. This paper reviews the signaling pathways by which Bmal1 regulates bone/cartilage metabolism, the upstream regulatory factors that control Bmal1, and the current Bmal1 knockout mouse models for research. We hope to provide new insights for the prevention and treatment of bone/cartilage diseases related to circadian rhythms. [ABSTRACT FROM AUTHOR]

This literature review examines circadian rhythms, highlighting the crucial role of transcription factors in regulating gene expression, influencing plant and animal behavior, and affecting human disease. It examines the roles of basic transcriptional regulation in circadian rhythms, such as histone modifications, chromatin remodeling, and Pol II pausing control. The review also discusses further progress in the fine regulation of circadian rhythms and the importance of transcriptional regulation in circadian rhythms. This paper underscores the significant link between transcription factors and circadian rhythms, highlighting the latter's contribution to improving human well-being. Almost all organisms, from the simplest bacteria to advanced mammals, have a near 24 h circadian rhythm. Circadian rhythms are highly conserved across different life forms and are regulated by circadian genes as well as by related transcription factors. Transcription factors are fundamental to circadian rhythms, influencing gene expression, behavior in plants and animals, and human diseases. This review examines the foundational research on transcriptional regulation of circadian rhythms, emphasizing histone modifications, chromatin remodeling, and Pol II pausing control. These studies have enhanced our understanding of transcriptional regulation within biological circadian rhythms and the importance of circadian biology in human health. Finally, we summarize the progress and challenges in these three areas of regulation to move the field forward. [ABSTRACT FROM AUTHOR]

Melatonin is vital in human circadian rhythm and infant development. This scoping review summarized the current knowledge about melatonin's presence and effects in human milk to promote better understanding of its secretion pattern and clinical advancement of maternal-infant health. The review followed the Joanna Briggs Institute guideline and answered the question: What is the current knowledge about melatonin hormone in human milk? The databases searched were PubMed, CINAHL, SCOPUS, Web of Science, LILACS, Scielo, EMBASE, Science Direct, Eric, Cochrane, in addition to grey literature and reference lists of included sources. Research papers included English, Spanish, or Portuguese languages, regardless of study type or publication date. The study selection and data extraction involved two independent reviewers. Twenty-nine studies met inclusion criteria. The studies, conducted between 1993 and 2023, employed diverse designs, with cross-sectional studies being the most prevalent. Melatonin concentration exhibited a consistent pattern, being higher at night, and elevated in colostrum. The analysis methods for melatonin concentration evolved, with recent advancements contributing to more accurate measurements. Factors influencing melatonin levels, such as delivery type, maternal age, and health conditions, demonstrated a complex relationship, potentially impacting the health and development of infants. The dynamic nature of melatonin in human milk calls for continued interdisciplinary research, bridging gaps between clinical, biochemical, and epidemiological perspectives. Standardizing melatonin analysis methods are needed. Nurses should assess factors influencing melatonin levels in milk to promote interventions and guidance aimed at enhancing the regulation of the circadian cycle during the perinatal period and its benefits. [ABSTRACT FROM AUTHOR]

Rapid, ultradian biological rhythms are only partly comparable to circadian (24-h) rhythms. Often, the ensuing expectations from this comparison are that 1) ultradian rhythms should be driven by discrete oscillators, 2) they are biochemically buffered, and 3) they must be functionally linked to extrinsic events and cycles. These three expectations are not always met, but perhaps there is an adaptive benefit to ultradian rhythms not meeting these expectations, which sets them functionally apart from circadian rhythms. In view of the extensive descriptions of the manifold types of ultradian rhythms across all biological levels (e.g., see papers in this research topic), it seems important to ask whether we should actively create a new set of definitions and expectations. To make a start, we here lay out some important questions we need to ask about ultradian rhythms. We then illustrate how these questions highlight one key area of exploration: the linked expression of ultradian rhythms in metabolism and behaviour and the role this plays in addressing a negative energy balance. [ABSTRACT FROM AUTHOR]

Terpenoids are valued chemicals in the pharmaceutical, biotechnological, cosmetic, and biomedical industries. Biosynthesis of these chemicals relies on polymerization of Isopentenyl di-phosphate (IPP) and/or dimethylallyl diphosphate (DMAPP) monomers, which plants synthesize using a cytosolic mevalonic acid (MVA) pathway and a plastidic methyleritritol-4-phosphate (MEP) pathway. Circadian regulation affects MVA and MEP pathway activity at three levels: substrate availability, gene expression of pathway enzymes, and utilization of IPP and DMAPP for synthesizing complex terpenoids. There is a gap in understanding the interplay between the circadian rhythm and the dynamics and regulation of the two pathways. In this paper we create a mathematical model of the MVA and MEP pathways in plants that incorporates the effects of circadian rhythms. We then used the model to investigate how annual and latitudinal variations in circadian rhythm affect IPP and DMAPP biosynthesis. We found that, despite significant fluctuations in daylight hours, the amplitude of oscillations in IPP and DMAPP concentrations remains stable, highlighting the robustness of the system. We also examined the impact of removing circadian regulation from different parts of the model on its dynamic behavior. We found that regulation of pathway substrate availability alone results in higher sensitivity to daylight changes, while gene expression regulation alone leads to less robust IPP/DMAPP concentration oscillations. Our results suggest that the combined circadian regulation of substrate availability, gene expression, and product utilization, along with MVA- and MEP-specific regulatory loops, create an optimal operating regime. This regime maintains pathway flux closely coupled to demand and stable across a wide range of daylight hours, balancing the dynamic behavior of the pathways and ensuring robustness in response to cellular demand for IPP/DMAPP. [ABSTRACT FROM AUTHOR]

Copyright of Enfermería Global is the property of Servicio de Publicaciones de la Universidad de Murcia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We have developed a one-dimensional second-order closure numerical model to study the vertical turbulent transport of trace reactive species in the convective (daytime) planetary boundary layer (CBL), which we call the Second-Order Model for Conserved and Reactive Unsteady Scalars (SOMCRUS). The temporal variation of the CBL depth is calculated using a simple mixed-layer model with a constant entrainment coeffcient and zero-order discontinuity at the CBL top. We then calculate time-varying continuous profiles of mean concentrations and vertical turbulent fluxes, variances, and covariances of both conserved and chemically-reactive scalars in a diurnally-varying CBL. The set of reactive species is the O3-NO-NO2 triad. The results for both conserved and reactive species are compared with large-eddy simulations (LES) for the same free-convection case using the same boundary and initial conditions. For the conserved species, we compare three cases with difierent combinations of surface fluxes, and CBL and free-troposphere concentrations. We find good agreement of SOMCRUS with LES for the mean concentrations and fluxes of both conserved and reactive species except near the CBL top, where SOMCRUS predicts a somewhat shallower depth, and has sharp transitions in both the mean and turbulence variables, in contrast to more smeared out variations in the LES due to horizontal averaging. Furthermore, SOMCRUS generally underestimates the variances and species-species covariances. SOMCRUS predicts temperature-species covariances similar to LES near the surface, but much smaller magnitude peak values near the CBL top, and a change in sign of the covariances very near the CBL top, while the LES predicts a change in sign of the covariances in the lower half of the CBL. SOMCRUS is also able to estimate the intensity of segregation (the ratio of the species-species covariance to the product of their means), which can alter the rates of second-order chemical reactions; however, for the case considered here, this efiect is small. The simplicity and extensibility of SOMCRUS means that it can be utilized for a broad range of turbulence mixing scenarios and sets of chemical reactions in the planetary boundary layer; it therefore holds great promise as a tool to incorporate these processes within air quality and climate models. [ABSTRACT FROM AUTHOR]

The main scientific result of this paper is the demonstration of the fact that tidal effects induced by the Moon affect the Schumann resonance amplitudes measured at magnetometers located at different geographical locations of the Global Coherence Monitoring System. Each magnetometer is paired with the closest monitoring station of the global tidal wave measurement network. This paper introduces the Schumann Resonance Complexity Index (SRCI), computed by using the calibrated H-rank algorithm on the local magnetic field data recorded by each magnetometer of the Global Coherence Monitoring System. Tidal wave data recorded at each monitoring station are also used to compute the Tidal Wave Complexity Index (TWCI). Eliminating diel cycles from the SRCI data yields significant statistical correlations between the SRCI and TWCI data, proving the hypothesis of tidal effects on the global network of magnetometers. [ABSTRACT FROM AUTHOR]

Driving is an everyday activity but also brings a substantial risk. Driver state monitoring is a potential method to alleviate such risk by detecting unsafe driver states. Monitoring systems can infer a driver's state based on physiological measurements, subjective report and/or performance. It is well-known that driver psychology, physiology and performance are affected by circadian rhythmicity independently from being affected by the psychological state. However, there is a paucity of research for the circadian effect on the interpretation of the driver state monitoring. This paper seeks to rectify this situation by reviewing the literature on the circadian effect on the physiological functions measured by the methods used in driver state monitoring. Systems tested in the laboratory as potential driver state monitoring and measures that are used to detect states are also considered. The findings suggest different circadian effects on electroencephalography, electrocardiography, electrooculography, electrodermal response, speech, event-related potential, electromyography, subjective report, blood pressure, facial expression, hormonal salivary content, body temperature, respiration, psychomotor performance, and body position. This study creates a theoretical basis for integrating studies about circadian rhythmicity into driver state monitoring. It shows the importance of circadian phase for the safety sciences, driver state monitoring, and systems design. [ABSTRACT FROM AUTHOR]

We reviewed the role of melanopsin-containing intrinsically photosensitive retinal ganglion cells (ipRGCs) in light-dependent functions, including circadian rhythm that is important for health, pupil responses and visual perception. We then discussed the implications for lighting design. Finally we described a five-primary photostimulating method that can independently control melanopsin activation in humans. [ABSTRACT FROM AUTHOR]

Oncidium hybridum is one of the important cut-flowers in the world. However, the lack of aroma in its cut-flower varieties greatly limits the sustainable development of the Oncidium hybridum cut-flowers industry. This paper is an integral investigation of the diel pattern and influencing factors of the aroma release of Oncidium Twinkle 'Red Fantasy'. GC-MS analysis revealed that the release of 3-Carene peaked at 10:00, while Butyl tiglate and Prenyl senecioate did so at 14:00, with a diel rhythm. By analyzing the correlation network between aroma component synthesis and differentially expressed genes, 15 key structural genes were detected and regulated by multiple circadian rhythm-related transcription factors. Cluster-17371.18_TPS, Cluster-65495.1_TPS, Cluster-46699.0_TPS, Cluster-60935.10_DXS, Cluster-47205.4_IDI, and Cluster-65313.7_LOX were key genes in the terpenoid and fatty acid derivative biosynthetic pathway, which were co-expressed with aroma release. Constant light/dark treatments revealed that the diurnal release of 3-Carene may be influenced by light and the circadian clock, and Butyl tiglate and Prenyl senecioate may be mainly determined by endogenous circadian clock. Under constant light treatment, the TPS, DXS, IDI, and LOX genes seem to lose their regulatory role in the release of aroma compounds from Oncidium Twinkle 'Red Fantasy'. Under constant dark treatment, the TPS genes were consistent with the release pattern of 3-Carene, which may be a key factor in regulating the diel rhythm of 3-Carene biosynthesis. These results laid a theoretical foundation for the study of floral transcriptional regulation and genetic engineering technology breeding of Oncidium hybridum. [ABSTRACT FROM AUTHOR]

The human body's physiological and behavioral activities are largely regulated by circadian rhythms. Chronotype predispose individuals to health problems. This paper emphasizes the importance of integrating chronotype assessments into studies on circadian rhythm and health. Precise risk assessments could result from this approach, especially in Asia and northern latitudes. [ABSTRACT FROM AUTHOR]

In today's hectic lifestyle, prioritizing health and wellness can seem daunting. However, the concept of time-restricted eating (TRE) offers a promising solution by leveraging the timing of meals to enhance health outcomes. This paper explores the evolution, mechanisms, and potential benefits of TRE, emphasizing its impact on metabolic health, digestion, and the gut microbiome. The Scopus, PubMed, and Google Scholar databases were searched for articles. Search terms included "time-related diet", "obesity and circadian enzyme rhythm", "chronobiology and obesity" and "microbiota and time-related diet". References from reviews were searched for additional articles and case reports. A manual search was also conducted based on citations in the published literature. Grounded in our evolutionary history, TRE aligns with our natural circadian rhythms, optimizing metabolic processes and hormone regulation. Through modulation of insulin sensitivity and glucose regulation, TRE exhibits promise in weight management and reducing the risk of chronic diseases such as type 2 diabetes and cardiovascular disorders. Additionally, TRE influences metabolism, digestion, and gut microbiota diversity, supporting overall health and potentially enhancing longevity. Strategies for implementing TRE into daily routines, including meal timing adjustments and mindful eating practices, are discussed, emphasizing individualization and sustainability. Furthermore, misconceptions, potential side effects, and considerations for specific populations are addressed, highlighting the importance of informed decision-making and consultation with healthcare professionals. While TRE offers a holistic approach to health optimization, future research is needed to elucidate its long-term effects and optimize its application across diverse populations. By embracing the principles of chrono-nutrition and integrating TRE into lifestyle choices, individuals can take proactive steps towards enhancing their well-being and fostering a healthier future. [ABSTRACT FROM AUTHOR]

The interpretation of laboratory data is a comparative procedure. Physicians typically need reference values to compare patients' laboratory data for clinical decisions. Therefore, establishing reliable reference data is essential for accurate diagnosis and patient monitoring. Human metabolism is a dynamic process. Various types of systematic and random fluctuations in the concentration/activity of biomolecules are observed in response to internal and external factors. In the human body, several biomolecules are under the influence of physiological rhythms and are therefore subject to ultradian, circadian and infradian fluctuations. In addition, most biomolecules are also characterized by random biological variations, which are referred to as biological fluctuations between subjects and within subjects/individuals. In routine practice, reference intervals based on population data are used, which by nature are not designed to capture physiological rhythms and random biological variations. To ensure safe and appropriate interpretation of patient laboratory data, reference intervals should be personalized and estimated using individual data in accordance with systematic and random variations. In this opinion paper, we outline (i) the main variations that contribute to the generation of personalized reference intervals (prRIs), (ii) the theoretical background of prRIs and (iii) propose new methods on how to harmonize prRIs with the systematic and random variations observed in metabolic activity, based on individuals' demography. [ABSTRACT FROM AUTHOR]

Oceans are a net source of molecular hydrogen (H2) to the atmosphere, where nitrogen (N2) fixation is assumed to be the main biological production pathway besides photo-chemical production from organic material. The sources can be distinguished using isotope measurements because of clearly differing isotopic signatures of the produced hydrogen. Here we present the first ship-borne measurements of atmospheric molecular H2 mixing ratio and isotopic composition at the West African coast of Mauritania (16-25° W, 17-24° N). This area is one of the biologically most active regions of the world's oceans with seasonal upwelling events and characterized by strongly differing hydro-graphical/biological properties and phytoplankton community structures. The aim of this study was to identify areas of H2 production and distinguish H2 sources by isotopic signatures of atmospheric H2. Besides this a diurnal cycle of atmospheric H2 was investigated. For this more than 100 air samples were taken during two cruises in February 2007 and 2008, respectively. During both cruises a transect from the Cape Verde Island towards the Mauritanian Coast was sampled. In 2007 additionally four days were sampled with a high resolution of one sample per hour. Our results clearly indicate the influence of local sources and suggest the Banc d'Arguin as a pool for precursors for photochemical H2 production, whereas N2 fixation could not be identified as a H2 source during these two cruises. With our experimental setup we could demonstrate that variability in diurnal cycles is probably influenced and biased by released precursors for photochemical H2 production and the origin of air masses. This means for further investigations that just measuring the mixing ratio of H2 is insufficient to explain the variability of a diurnal cycle and support is needed, e.g. by isotopic measurements. However, measurements of H2 mixing ratios, which are easy to conduct online during ship cruises could be a helpful tool to easily identify production areas of biological precursors such as VOC's for further investigations. [ABSTRACT FROM AUTHOR]