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This article addresses two questions, why certain animals (frogs, breaststroke swimmers, hovering fliers, jellyfish) push rapidly against the surrounding fluid and then reach forward slowly, and whether this rhythm of propulsion is a manifestation of the universal phenomenon of design evolution in nature. Emphasis is on the distribution of time periods of locomotion in which, during the driving phase of cyclic movement (the motive stroke, phases 1 and 2, in alternating sequence with the dissipative stroke, phase 3), the work is generated (phase 1) and dissipated (phase 2). The relative lengths of the characteristic times t1 and t2 of the phases 1 and 2, are predicted. The relative duration of the proposed three phases of a cycle is the 'rhythm'. The analysis is based on a model of how the effective cross-sections of the stroking body parts impact the surrounding medium, water, or air, and the total power required to account for the kinetic energy losses during phases 2 and 3, which are due to drag forces posed by the surrounding medium. The body configuration (limbs' cross-sections) determines the limbs' velocities that maximize mean power, and the times t1 and t2 within the motive stroke. Emphasis is placed on the freedom to change the evolving design. Freedom is represented in two ways: the number of degrees of freedom in changing the dimensions of the model and its deformation in time, and the effect that evolutionary changes have on the access that the body has to its available space. Freedom to change the locomotion design leads to greater power and speed. [ABSTRACT FROM AUTHOR]

Atrial fibrillation (AF) is a prevalent cardiac condition predominantly affecting older adults, characterized by irregular heartbeat rhythm. The condition often leads to significant disability and increased mortality rates. Traditionally, two therapeutic strategies have been employed for its treatment: heart rate control and rhythm control. Recent clinical studies have emphasized the critical role of early restoration of sinus rhythm in improving patient outcomes. The persistence of the irregular rhythm allows for the progression and structural remodeling of the atria, eventually leading to irreversible stages, as observed clinically when AF becomes permanent. Cardioversion to sinus rhythm alters this progression pattern through mechanisms that are still being studied. In this review, we provide an in-depth analysis of the pathophysiological mechanisms responsible for maintaining AF and how they are modified during sinus rhythm restoration using existing therapeutic strategies at different stages of clinical investigation. Moreover, we explore potential future therapeutic approaches, including the promising prospect of gene therapy. [ABSTRACT FROM AUTHOR]

This paper examines the relationship between rhythm, place, and race. It argues that Roland Barthes' concept of idiorhythmy is useful for understanding the politics of rhythm in relation to race. The paper explores how rhythm has been used to think about the interrelatedness of place and mobility – adding dynamism to place. I analyze reactions to the performance of Stravinsky's Le Sacre du Printemps to demonstrate how rhythm has been culturally and politically encoded through discursive and conceptual links to geographical imaginaries of place. The paper also explores how rhythm has been used to locate Black people in White western thought, and how it has been mobilized in Black and anti-racist thought. The concept of idiorhythmy is used to suggest the radical possibility of places of other rhythms, outside of the dominant rhythms of the world. Throughout the paper, it is argued that an understanding of rhythm is useful for delineating the interplay between place, race, and power. [ABSTRACT FROM AUTHOR]

This short article shares the innovative pedagogic practices I explored and developed to nurture temporal reflexivity in the classroom to engage students in the study of the sociology of time in the context of the COVID-19 pandemic and a local strike. It takes the reader through the module as it was structured and delivered in two parts: from calendars to calibration and from memory to procrastination. This is interspersed with details of the learning exercises we undertook in the classroom and the module assignments. [ABSTRACT FROM AUTHOR]

This paper focuses on the musical analysis of Veress’s orchestral composition, Threnos. Written in 1945 and dedicated to the memory of Bartók, it is a one-movement work, divided into three independent internal sections, each of them representing an orchestral gradation. Being a threnody, Veress inserts two folk-like funeral laments, which are the composer’s melodic inventions, in the style of folk music. Veress, the ethnomusicologist and composer presents the bartókian principle of how to capture the ethos of folk music in its structure, melody, harmony, and rhythm, and how to express it in such a modern and innovative way, that a completely new quality is born from it. [ABSTRACT FROM AUTHOR]

Under conditions of prolonged durations of warmth, flies counter potential temperature stress by shifting their locomotor activity from day into night when the conditions are likely to be less harsh. Modulation of a rhythmic behavior such as this in response to the environment would require interaction between at least 2 neuronal systems: (1) a sensory system to receive input from the environment, and (2) the internal clock to correctly time rhythmic activity in response to this thermosensory input. Our previous studies found that a thermosensory mutant of the ion channel Drosophila Transient Receptor Potential-A1 (dTRPA1) failed to shift activity into the dark like control flies do and also identified the role of a specific cluster of the dTRPA1 -expressing neurons, the dTRPA1 sh+neurons necessary for this. In this study, we extended our previous findings and characterized the identity of these dTRPA1 sh+ neurons based on their overlap with circadian neurons. Utilizing various genetic manipulations, we asked whether the overlapping neurons could be potential points of intersection between the 2 circuits that modulate behavior under warm temperature, meaning whether they function as both—sensory and clock neurons. We found that the molecular clock within the dTRPA1 sh+ cluster was not necessary, but the expression of dTRPA1 in a subset of circadian neurons, the small ventrolateral neurons (sLNvs), was necessary in modulating phasing of behavior under warm temperature. Furthermore, attempting to identify the neuronal circuit, we were able to uncover the potential roles of serotonin and acetylcholine in modulating this temperature-dependent behavior. Finally, we also discuss possible parallel neuronal pathways that may exist to give rise to this modulation of behavior under warm temperature, thereby supporting and expanding the knowledge of the field about circuits that control temperature-mediated behavioral outcomes. [ABSTRACT FROM AUTHOR]

Beyond visual perception, light has non-image-forming effects mediated by melanopsin-expressing, intrinsically photosensitive retinal ganglion cells (ipRGCs). The present study first used multielectrode array recordings to show that in a diurnal rodent, Nile grass rats (Arvicanthis niloticus), ipRGCs generate rod/cone-driven and melanopsin-based photoresponses that stably encode irradiance. Subsequently, two ipRGC-mediated non-image-forming effects, namely entrainment of daily rhythms and light-induced arousal, were examined. Animals were first housed under a 12:12 h light/dark cycle (lights-on at 0600 h) with the light phase generated by a low-irradiance fluorescent light (F12), a daylight spectrum (D65) stimulating all photoreceptors, or a narrowband 480 nm spectrum (480) that maximized melanopsin stimulation and minimized S-cone stimulation (λmax 360 nm) compared to D65. Daily rhythms of locomotor activities showed onset and offset closer to lights-on and lights-off, respectively, in D65 and 480 than in F12, and higher day/night activity ratio under D65 versus 480 and F12, suggesting the importance of S-cone stimulation. To assess light-induced arousal, 3-h light exposures using 4 spectra that stimulated melanopsin equally but S-cones differentially were superimposed on F12 background lighting: D65, 480, 480 + 365 (narrowband 365 nm), and D65 − 365. Compared to the F12-only condition, all four pulses increased in-cage activity and promoted wakefulness, with 480 + 365 having the greatest and longest-lasting wakefulness-promoting effects, again indicating the importance of stimulating S-cones as well as melanopsin. These findings provide insights into the temporal dynamics of photoreceptor contributions to non-image-forming photoresponses in a diurnal rodent that may help guide future studies of lighting environments and phototherapy protocols that promote human health and productivity. [ABSTRACT FROM AUTHOR]

Summary: Accelerated idioventricular rhythms (AIVR) are increasingly diagnosed in horses, particularly in those with underlying systemic disease. Recognition of these abnormal rhythms is important but specific treatment is often not necessary unless the rhythms become haemodynamically relevant, with AIVR often resolving as the systemic disease improves. The goals of treatment, when indicated, include improving cardiac output, decreasing systemic and myocardial inflammation (if present) and controlling the ventricular rate and rhythm. Identification of any persistent myocardial damage or arrhythmia burden will be important for the prognosis and risk assessment of these patients in the longer term. [ABSTRACT FROM AUTHOR]

Heartbeat rhythms are related to a complex dynamical system based on electrical activity of the cardiac cells usually measured by the electrocardiogram (ECG). This paper presents a mathematical model to describe the electrical activity of the heart that consists of three nonlinear oscillators coupled by delayed Duffing-type connections. Coupling alterations and external stimuli are responsible for different cardiac rhythms. The proposed model is employed to build synthetic ECGs representing a variety of responses including normal and pathological rhythms: ventricular flutter, torsade de pointes, atrial flutter, atrial fibrillation, ventricular fibrillation, polymorphic ventricular tachycardia and supraventricular extrasystole. Moreover, the sinoatrial rhythm variations are described by time-dependent frequency, representing transient disturbances. This kind of situation can represent transitions between different pathological behaviors or between normal and pathological physiologies. In this regard, a nonlinear dynamics perspective is employed to describe cardiac rhythms, being able to represent either normal or pathological behaviors. [ABSTRACT FROM AUTHOR]

Individuals have unique typing rhythms characterized by specific keystroke dynamics. Changes in state and cardiovascular responding are well documented manifestations of the fight‐flight response to stress. However, as stress also leads to changes in muscle tone and motor control, typing rhythms may also be impacted. We aim to determine which individuals are experiencing stress through their typing rhythms and identify universal keystroke markers of stress. Participants (N = 116) typed 80 repetitions of a 6‐word, 30‐character phrase before and after 15 min of critically evaluated multitasking stress. Cardiovascular, hemodynamic, and state variables were compared across baseline, stress, and recovery periods and measures of typing rhythm were derived for each period and classified using machine‐learning algorithms. Critically evaluated multitasking led to significant changes in all stress measures, demonstrating highly robust stress reactivity. Machine learning algorithms accurately classified stressed typing for each individual based on their typing rhythms; however, no universal keystroke markers of stress were identified. Using typing rhythms. We were able to determine whether an individual was stressed or not, but the markers used for classification differed between individuals. These individual changes may provide opportunities for identifying stressful periods through keystroke monitoring, as well as the potential for early identification of disorders which may impact fine motor control. Typing rhythms could therefore be used to monitor health and well‐being in individuals who use keyboards in various situations. This is the first rigorous assessment of stress and typing rhythms and has led to the development of a feasible and highly reproducible research protocol. Individuals can be identified through their unique typing rhythms. These typing rhythms also change during stressful experiences such that typing produced during stress can be accurately distinguished from typing during neutral periods. Typing rhythms could therefore be used to monitor individuals long‐terms stress‐induced performance and wellbeing. [ABSTRACT FROM AUTHOR]

Aim: The aim of the present study was to assess the Safety and Efficacy of Planned Synchronized Cardioversion of Drug Resistant Cardiac Tachyarrhythmia under Day Care Anesthesia. Methods: This was an Observational Retrospective study to determine the Safety and Efficacy of Planned Synchronized Cardioversion of Drug Resistant Cardiac Tachyarrhythmia under Day Care. Data was collected from CIMS Hospital. For the study pre - ECG findings/outcomes (e.g. Atrial flutter, Atrial fibrillation) and post-ECG findings/outcomes (e.g. restoration of normal sinus rhythm) were observed. 75 patients were included in the study. Results: A total of 75 Patients with mean age of 59.10 (18 to 84 years) were evaluated. SD=12.75 we had a patients with minimum age of 27 years and maximum age of 84, weight with mean of (71.87), SD=13.94 the patients with minimum weight of 49.6 kilograms, and maximum weight of 145 kilograms. Height with mean of (163.29) SD=15.81, minimum height of 143 centimeters and maximum height of 182 centimeters. The factors affecting/finding comorbidities in total of 75 patients, A total of 6 (8%) patients had inserted pacemaker, CRT in total of 2 (2%), CRTD in total of 6 (8%). Comparison in pair 1 shows dbp post-dbp approx. mean value between lower limit and upper limit (-2.283, 4.483) with p-value (0.476) was nonsignificant. In pair 2 HR- post HR approx. mean value between lower limit and upper limit (32.335, 47.585) with p-value (0.0005) was significant. In comparison with pair 3 sbp post-sbp approx. mean value between lower limit and upper limit (-4.060, 6.966) with p-value (0.601) was nonsignificant comparison with pair 4 spO2_post-spO2 approx. mean value between lower limit and upper limit (0.127, 3.265) with p-value (0.034) was significant. Conclusion: The result findings showed that main parameters of the study was significant in comparison between heart rate (p<0.05). A total of 71(95%) subjects had restoration of normal sinus rhythm. Overall, it can be concluded that the cardioversion was one of the best way for restoration of normal sinus rhythm in cardiac tachyarrhythmia disorder. [ABSTRACT FROM AUTHOR]

Attention can be selectively tuned to particular features at different spatial locations or objects. The deployment of attention can be guided by properties, such as color, orientation, and so forth, as guiding features. What might be such guiding features for visual stimuli under dynamic rhythmic conditions? We asked specifically what might be the parameters that attract attention when perceiving a visual rhythm. We used a visual search paradigm, in which a dynamic search display consisted of vertically "bouncing balls" with regular rhythms. The search target was defined by a unique visual rhythm (i.e., with either a shorter or longer period) among rhythmic distractors sharing an identical period. We modulated amplitudes and phases of the distractor balls systematically. The results showed a crucial factor of the phase, not the amplitude. If the phase is violated, the target suddenly "pops out" as an "oddball," showing an efficient parallel search. The findings indicate in general the essential role of the phase in conjunction with amplitude and period for visual rhythm perception. Furthermore, a higher saliency of moving objects with a higher frequency component has also been disclosed. [ABSTRACT FROM AUTHOR]

Measuring glucocorticoids is one of the most reliable and widely used techniques to monitor stress responses, however invasive techniques to collect plasma samples may not be applicable for wild populations. Monitoring excreted glucocorticoids is an effective noninvasive technique that researchers have used increasingly over the past two decades, and it has allowed the investigation of glucocorticoids in a variety of species with a range of activity patterns. Many species exhibit predictable circadian patterns of glucocorticoid secretion in accordance with their daily activity pattern. There remains a gap in our understanding of how excreted glucocorticoid metabolites vary throughout the day and across species, despite the utility of this information when developing sampling protocols and analyzing data. We investigated circadian patterns of glucocorticoid excretion in a cathemeral primate species, Eulemur rubriventer (red‐bellied lemur), in Ranomafana National Park, Madagascar. We collected fecal samples from 10 individuals throughout the day and analyzed fecal glucocorticoid levels across three time points (Early, Midday, and Late), and again across two time points (Morning and Afternoon). We also investigated whether activity pattern, sex (as a control variable), and other traits associated with gut passage rate (diet, body mass) could help predict the presence and timing of circadian patterns of fecal glucocorticoid metabolites across mammal species. We found that fecal glucocorticoid metabolite levels in E. rubriventer fluctuate throughout the day, with lowest levels in the morning and peak levels in the afternoon. None of the variables that we tested predicted whether daily fecal glucocorticoid metabolites changed significantly throughout the day, nor when levels were likely to peak, across species. We stress the importance of controlling for sampling time and reporting these results as standard practice in studies of fecal glucocorticoid metabolites. Research highlights: Fecal glucocorticoids change significantly throughout the day in cathemeral Eulemur rubriventer, with lowest levels in the morning.Across species, activity pattern and traits associated with gut passage rate did not predict whether fecal glucocorticoid metabolites changed significantly with time.Circadian patterns of glucocorticoid excretion need to be investigated on a species‐by‐species basis and used to inform sampling protocols and data analysis. [ABSTRACT FROM AUTHOR]

Milk synthesis exhibits a daily rhythm that is modified by the timing of feed intake. However, it is unknown how specific nutrients entrain this daily rhythm. Amino acids have an important role in milk synthesis, and may have a role in entrainment of mammary circadian rhythms. The objective of this study was to determine the effects of intestinally absorbed protein on daily rhythms of milk and milk component synthesis and key plasma hormones and metabolites. Nine lactating Holstein cows were assigned to 1 of 3 treatment sequences in a 3 × 3 Latin square. Treatments included abomasal infusions of 500 g/d of sodium caseinate either continuously throughout the day (CON), for 8 h/d from 0900 to 1700 h (DAY), or for 8 h/d from 2100 to 0500 h (NGT). Cows were milked every 6 h during the final 8 d of each period. A 24-h rhythm was fit to data using cosine analysis and the amplitude and acrophase were determined. Night infusion of protein decreased the daily milk yield and milk protein yield by 8.2% and 9.2%, respectively. Milk fat yield was increased 5.5% by DAY and milk fat concentration was increased 8.8% by NGT. Milk yield exhibited a daily rhythm in all treatments, with NGT increasing the amplitude of the daily rhythm 33% compared with CON. Milk fat concentration fit a daily rhythm in CON and NGT, but not DAY, whereas milk protein concentration fit a daily rhythm in CON and DAY, but not NGT. Moreover, DAY abolished the daily rhythm of plasma glucose concentration, but induced rhythms of plasma insulin and nonesterified fatty acid concentrations. Results suggest that feeding increased protein levels during the early part of the day may increase milk fat yield and modify energy metabolism through increased daily variation in insulin-stimulated lipid release, but additional research focused on feeding multiple diets across the day is required. [ABSTRACT FROM AUTHOR]

Rhythmic stability (nonrandom temporal structure) is required for many neural and physiological functions, whereas rhythmic irregularities can indicate genetic or developmental deficiencies. Therefore, rhythmic courtship or contest signals are widespread in nature as honest advertisement displays. Examination of bird songs revealed the pervasiveness of categorical rhythmic patterns that can be described as small integer ratios between sequential inter‐call intervals. As similar rhythmic profiles are prevalent in human music, it was suggested that a shared functionality could drive both animal songs and human musical rhythms, facilitating synchrony between signallers and enabling easy identification of performance errors.Here we examined whether the rhythmic structure and the rhythmic stability of vocal displays are related to reproductive success in male rock hyraxes (Procavia capensis), which presents an unusual case of a terrestrial singing mammal.We combined long‐term parentage analysis of 13 male hyraxes (22 male/years) with an analysis of an audio library of 105 hyrax songs. Male annual reproductive success was determined by the number of offspring that survived to the age of 1 year. The frequency of singing events was used to determine the seasonal singing effort for each male. Songs were analysed for rhythmic structure, focusing on the presence of categorical rhythms and the contribution of rhythmic stability to annual reproductive success.We found that male hyraxes that sing more frequently tend to have more surviving offspring and that the rhythmic profile of hyrax songs is predominantly isochronous with sequential vocal element pairs nearly equally spaced. The ratio of isochronous vocal element transitions (on‐integer) to element transitions that deviate from an isochronous pattern (off‐integer) in hyrax songs is positively correlated with male reproductive success.Our findings support the notion that isochronous rhythmic stability can serve as an indication of quality in sexually selected signals and is not necessarily driven by the need for multiple caller synchronization. The relative scarcity of nonisochronous rhythmic categories in individually performed hyrax songs raises the question of whether such rhythmic categories could be a product of collective, coordinated signalling, while being selected against in individual performance. [ABSTRACT FROM AUTHOR]

This article analyses audience responses to two creative works inspired by traumatic loss—the first, a performance presentation, recounting events from the author's adolescence; the second, a short film about a suicide in the filmmaker's family. Both were shown in 2017 as part of a mental health arts festival, attracting audiences with affinity for the lived experiences portrayed. Given the potential for such works to give rise to negative feelings and/or to retrigger trauma, the objective of this research was to understand firstly whether audiences could process the trauma conveyed in a contained and facilitative setting and, secondly, how the specific aesthetic modality of each work supported this processing. The psychosocial methodology adopted consisted of a group-based, image-led associative method—the visual matrix—which invites participants to express their sensory-affective and felt responses to a creativework. In the case of both works, the visual matrix gave rise to a distinctive form of aesthetic enactment, expressed through rhythm and image association. This imagistic and 'rhythmic' mode of engagement appeared to be key to the re-symbolisation of trauma for the audiences. The implication of this study is that the re-visiting of potentially distressing experiences in an aesthetically mediated, containing setting is potentially reparative in its effect. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine whether whole body vibration increases movement variability while performing a half squat with different ballasts and rhythms through entropy. A total of 12 male athletes (age: 21.24 ± 2.35 years, height: 176.83 ± 5.80 cm, body mass: 70.63 ± 8.58 kg) performed a half squat with weighted vest, dumbbells and bar with weights suspended with elastic bands, with and without vibration at the squat rhythm of 40 and 60 bpm. Each ballast corresponded to 15% of the body mass. The movement variability was analysed by calculating the sample entropy of the acceleration signal, recorded at the waist using an accelerometer. With vibration, differences were found between weighted vest and dumbbells (t(121) = -8.81, p < 0.001 at 40 bpm; t(121) = -8.18, p < 0.001 at 60 bpm) and between weighted vest and bar at both rhythms (t(121) = -8.96, p < 0.001 at 40 bpm; t(121) = -8.83, p < 0.001 at 60 bpm). Furthermore, a higher sample entropy was obtained at 40 bpm with all ballasts (t(121) = 5.65, p < 0.001 with weighted vest; t(121) = 6.27, p < 0.001 with dumbbells; t(121) = 5.78, p < 0.001 with bar). No differences were found without vibration. These findings reveal that adding mechanical vibration to a half squat produces a non-proportional increase in movement variability, being larger when the ballast is placed on the upper limbs and when performed at a slow rhythm. [ABSTRACT FROM AUTHOR]

Background: It is not clear whether the data regarding rhythm control during atrial fibrillation (AF) contained in AF registries is prognostically significant. Thus, this study investigated the relationship between rhythm control and cardiovascular outcomes in patients in contemporary AF registries. Methods: This study was conducted using data from 6670 patients with AF receiving oral anticoagulation in the CODE-AF registry. We used propensity overlap weighting to account for differences in baseline characteristics between the rhythm control and rate control groups. The primary outcome was a composite of the rate of death due to cardiovascular causes, stroke, acute coronary syndrome, and heart failure. The secondary outcomes were individual components of the primary outcome. Results: In the CODE-AF registry, 5407 (81.1%) patients were enrolled three months after AF diagnosis. During a median follow-up period of 973 days (interquartile range: 755–1089 days), a primary outcome event occurred in 72 patients in the rhythm control group (1.4 events per 100 person-years) and in 211 patients in the rate control group (1.8 events per 100 person-years). However, after overlap weighting, the incidence rates were 1.4 and 1.5 events per 100 person-years, respectively. No significant difference was found in either the primary outcome (weighted HR: 0.87; 95% CI: 0.66–1.17; p = 0.363) or secondary outcomes between the rhythm control and rate control groups. Conclusion: In a prospective AF registry in which most of the population was enrolled at least three months after AF diagnosis, no difference in the risk of cardiovascular or cerebrovascular outcomes was found between the rhythm control and rate control groups, suggesting the early rhythm control should be considered to improve the outcome of patients. [ABSTRACT FROM AUTHOR]

This article focuses on the need to reconnect with the Earth, not in an abstract sense, but in a real one, to lay the foundations that will allow us to achieve a deep understanding of the position that man occupies in the cosmos and, consequently, bring to light what really defines the human community. Likewise, it seeks to demonstrate, through the interpretation of texts by Hildegard of Bingen, Wendell Berry, and Maximus the Confessor, that it is not possible, without falling into error, to conceive humanity, the community, and the Church as separate realities from the Earth and the rest of Creation. I also maintain that only from a paradigm rooted in the Earth, with an agrarian and nonindustrial mentality, it is possible to rediscover the cosmic character of the Church in the connection between the cosmic and liturgical cycles. [ABSTRACT FROM AUTHOR]

Canards are a type of transient dynamics that occur in singularly perturbed systems, and they are specific types of solutions with varied dynamic behaviours at the boundary region. This paper introduces the emergence and development of canard phenomena in a neuron model. The singular perturbation system of a general neuron model is investigated, and the link between the transient transition from a neuron model to a canard is summarised. First, the relationship between the folded saddle-type canard and the parabolic burster, as well as the firing-threshold manifold, is established. Moreover, the association between the mixed-mode oscillation and the folded node type is unique. Furthermore, the connection between the mixed-mode oscillation and the limit-cycle canard (singular Hopf bifurcation) is stated. In addition, the link between the torus canard and the transition from tonic spiking to bursting is illustrated. Finally, the specific manifestations of these canard phenomena in the neuron model are demonstrated, such as the singular Hopf bifurcation, the folded-node canard, the torus canard, and the "blue sky catastrophe". The summary and outlook of this paper point to the realistic possibility of canards, which have not yet been discovered in the neuron model. [ABSTRACT FROM AUTHOR]

"Barberpole" tempo illusions are a family of auditory illusions based on the synchronization of faded rhythmic streams playing at different rates, often manufacturing experiences of seemingly eternal acceleration or deceleration. The forefather of all such illusions, based on layers whose rates are powers of two apart ("octaves"), was studied by Jean-Claude Risset in the late seventies and is now known as Risset rhythm. This article provides a mathematical framework for barberpole tempo illusions, generalizing Risset rhythms for arbitrary numbers of subdivisions, non-integer proportions, arbitrary rate modulation, and increasingly accelerating tempi. Furthermore, this article describes a new illusion of eternal rallentando/accelerando based on the full harmonic spectrum of rates. This construction shows that Risset rhythms are related to barberpole variable-rate polyrhythms. A notable application of the study of divisional structures that barberpole illusions underpin is the construction of bistable auditory figures (accelerating or decelerating depending on the stream being focused). [ABSTRACT FROM AUTHOR]

Background: Postoperative atrial fibrillation (POAF) is the most common complication after cardiac surgery; it is associated with morbidity and mortality. We undertook this review to compare the effects of rhythm vs. rate control in this population. Methods: We searched MEDLINE, Embase and CENTRAL to March 2023. We included randomized trials and observational studies comparing rhythm to rate control in cardiac surgery patients with POAF. We used a random-effects model to meta-analyze data and rated the quality of evidence using GRADE. Results: From 8,110 citations, we identified 8 randomized trials (990 patients). Drug regimens used for rhythm control included amiodarone in four trials, other class III anti-arrhythmics in one trial, class I anti-arrhythmics in four trials and either a class I or III anti-arrhythmic in one trial. Rhythm control compared to rate control did not result in a significant difference in length of stay (mean difference −0.8 days; 95% CI −3.0 to +1.4, I2 = 97%), AF recurrence within 1 week (130 events; risk ratio [RR] 1.1; 95%CI 0.6–1.9, I2 = 54%), AF recurrence up to 1 month (37 events; RR 0.9; 95%CI 0.5–1.8, I2 = 0%), AF recurrence up to 3 months (10 events; RR 1.0; 95%CI 0.3–3.4, I2 = 0%) or mortality (25 events; RR 1.6; 95%CI 0.7–3.5, I2 = 0%). Effect measures from seven observational studies (1428 patients) did not differ appreciably from those in randomized trials. Conclusions: Although atrial fibrillation is common after cardiac surgery, limited low-quality data guide its management. Limited available evidence suggests no clear advantage to either rhythm or rate control. A large-scale randomized trial is needed to inform this important clinical question. [ABSTRACT FROM AUTHOR]

The aim of our study was to investigate short- and medium-term survival in patients with sudden cardiac death (SCD) after resuscitation. We continued a retrospective study at the University of Pécs from April 2018 to December 2019. 192 patients with SCD were selected. Exclusion criteria were incomplete documentation and unstable rhythm, after which we continued the study with 181 patients. Our data were obtained from documents recorded by the Emergency Department. The study population was divided into two groups, with proven shockable (I) and non-shockable (II) initial rhythm, and their data were compared at hospital discharge, at 1 month, and at 3 months. The main endpoint was the mortality between the two groups. Our results already showed that hospital survival was significantly higher in the shockable rhythm group than in the non-shockable group (62% vs. 38%, P=0.002). We also obtained similar results for 1-month survival (54% vs. 16%, P=0.004). When risk factors were examined, there was a significant difference in the survival of diabetic (P=0.001) and hypertensive patients (P=0.001). Patients with shockable rhythm have significantly better survival rates. [ABSTRACT FROM AUTHOR]

This article examines two books that delve into cultural interactions in the Mediterranean during the Iron Age. While the authors take different approaches in presenting their findings, both books fail to thoroughly explore the concept of identities, despite recognizing their significance. The article suggests that further research is necessary to address this gap in scholarly literature. Additionally, the text emphasizes the importance of understanding small-scale social actions and variability within larger scales when studying connectivity, migration, and mobility in archaeology. It critiques the use of the terms "Phoenicianization" and "Orientalization" in archaeological research, arguing that they perpetuate a core-periphery perspective and essentialist groups, disregarding local perspectives and changes over time. The article also highlights the significance of considering the material dimension of social action and the role of gender in comprehending social change during the Iron Age. It criticizes the oversimplification of complex relationships and identities in the Mediterranean through the use of maps. Ultimately, the text calls for a more nuanced and inclusive approach to studying the Iron Age Mediterranean. [Extracted from the article]

Circadian rhythms of physiology, behavior, and metabolism have an endogenous 24 h period that synchronizes with environmental cycles of light/dark and food availability. Alterations in light cycles are stressful and disrupt such diurnal oscillations. Recently, we witnessed a sudden rise in studies describing the mechanisms behind the interaction between the key characteristics of mitochondrial functions, peripheral clocks, and stress responses. To our knowledge, there is no study in the suprachiasmatic nuclei (SCN) describing the dysregulated mitochondrial bioenergetics under abnormal lighting conditions, which is common in today's modern world. Thus, we aimed to investigate the existence of daily changes in mitochondrial bioenergetics (respiratory control rate, RCR), mitochondrial abundance (mtDNA/nDNA), plasma corticosterone, and to test whether disturbances in the lighting conditions might influence such rhythms. To confirm this, mice were sacrificed, mitochondria were isolated from the suprachiasmatic nuclei in the brain and blood was collected, every 3 h at various time points zeitgeber time/circadian time, (0, 3, 6, 9, 12, 15, 18, 21, and 24 h) under 12:12 h light-dark (LD, 150 lux L: 0 lux D) cycle and chronic artificial dim lighting (LL, 5 lux: 5lux) conditions, of a 24 h period, respectively. Our results demonstrate the existence of robust daily rhythmicity in RCR, mtDNA/nDNA and plasma CORT under a normal LD cycle. However, these rhythms were significantly disrupted and clock genes expressions were dysregulated under chronic dim LL. Furthermore, mitochondrial abundance was significantly reduced during LL compared to their numbers under LD cycle. Our data demonstrate that the circadian clock regulates mitochondrial functions (RCR, number), essential for accomplishing daily energy demands and supply by the SCN neurons. Abnormal light exposure dysregulates mitochondrial functions in the SCN and may alter metabolism, resulting in obesity, diabetes, and other metabolic disorders. Therefore, properly designing lighting conditions in workplaces is essential to mitigate the adverse consequences of light on humans. [ABSTRACT FROM AUTHOR]

Our lives and activities are influenced by specific, regular, and periodic biological cycles. There are theories claiming that health state, energy levels, emotions and cognitive ability can vary depending on these biological cycles. Understanding the rhythms of nature and our own organism can provide an interesting insight into our lives, but it is essential to approach these concepts with a critical spirit and evaluate them in the context of current scientific knowledge. It is important not to feel that we grow old with age (although physiologically, in good intellectual condition, the power to work and to love decreases considerably with aging) but, listening to our inner clock, to try to adapt to its rhythm. [ABSTRACT FROM AUTHOR]

This piece of research focuses on the first theoretical study published by Leoš Janáček and the way in which the composer understands to include contemporary and ancient philosophical and aesthetic principles in his thinking. We see how the author subordinates his theoretical musical thinking regarding rhythm and metre, as well as his concept of accents and nuances to those principles. My study sheds light on some unclear expressions, on other downright daring and novel ones, attempts to explain them and references the great Czech musician's subsequent theoretical contributions. Beyond statements and hypotheses, the conclusion that I have reached constitutes an impulse to continue the research and go thoroughly into the theoretical concepts set forth by one of the greatest thinker-musicians of humanity. [ABSTRACT FROM AUTHOR]

The first decades of the 20th century, particularly the post-war era, brought about numerous philosophical and cultural changes. Exoticism and orientalism were concepts that still governed arts and music, however the philosophical concepts that lay beyond the use of exotic or oriental themes was gradually altered. Exoticism represented more than the possibility for artists to create an idealized elsewhere, inspired by the contact with foreign cultures and their artistic products. It also offered artists the opportunity to express the complex meaning of various symbols associated with exoticism. In this context, Western society gradually turned toward a new aesthetic that could provide artists with an apparent connection to the roots of mankind. Primitivism, associated with folk art and mythology, represented a utopic state, prior to civilization or colonialism, but at the same time, it offered the possibility to explore certain archetypal symbols and express their possible meaning through art. Art nègre, represented by African and African American art and music, was most often associated with this aesthetic of primitivism, and influenced the works of Western artists. French composer Darius Milhaud returns to the theme of origins and creation in the work La création du monde, which combines elements associated with the concept of primitivism, with jazz music and Western compositional techniques. [ABSTRACT FROM AUTHOR]

The first decades of the 20th century, particularly the post-war era, brought about numerous philosophical and cultural changes. Exoticism and orientalism were concepts that still governed arts and music, however the philosophical concepts that lay beyond the use of exotic or oriental themes was gradually altered. Exoticism represented more than the possibility for artists to create an idealized elsewhere, inspired by the contact with foreign cultures and their artistic products. It also offered artists the opportunity to express the complex meaning of various symbols associated with exoticism. In this context, Western society gradually turned toward a new aesthetic that could provide artists with an apparent connection to the roots of mankind. Primitivism, associated with folk art and mythology, represented a utopic state, prior to civilization or colonialism, but at the same time, it offered the possibility to explore certain archetypal symbols and express their possible meaning through art. Art nègre, represented by African and African American art and music, was most often associated with this aesthetic of primitivism, and influenced the works of Western artists. French composer Darius Milhaud returns to the theme of origins and creation in the work La création du monde, which combines elements associated with the concept of primitivism, with jazz music and Western compositional techniques. [ABSTRACT FROM AUTHOR]

This piece of research focuses on the first theoretical study published by Leoš Janáček and the way in which the composer understands to include contemporary and ancient philosophical and aesthetic principles in his thinking. We see how the author subordinates his theoretical musical thinking regarding rhythm and metre, as well as his concept of accents and nuances to those principles. My study sheds light on some unclear expressions, on other downright daring and novel ones, attempts to explain them and references the great Czech musician's subsequent theoretical contributions. Beyond statements and hypotheses, the conclusion that I have reached constitutes an impulse to continue the research and go thoroughly into the theoretical concepts set forth by one of the greatest thinker-musicians of humanity. [ABSTRACT FROM AUTHOR]

This study aims to measure the daily melatonin secretory rhythms of people living in high-, mid-, and low-latitude regions characterised by different day lengths and global solar-radiation conditions. In Poland, a high-latitude region, the amount of melatonin secretion is greater, with secretion occurring earlier (exemplifying phase advance). On the other hand, in Vietnam, a low-latitude region, the level is lower and occurs later (phase delay). Japan, a mid-latitude region, shows behaviour intermediate between these two. Melatonin secretory rhythm in Vietnam is closely related to Day length and Global Solar Radiation, though no such relationship is observed in Poland or Japan, making it necessary for other factors to be considered. The results of this study have important implications considering the impacts of light pollution and lighting-related conditions of modern life. [ABSTRACT FROM AUTHOR]

Respiratory rhythms sustain biological life, governing the homeostatic exchange of oxygen and carbon dioxide. Until recently, however, the influence of breathing on the brain has largely been overlooked. Yet new evidence demonstrates that the act of breathing exerts a substantive, rhythmic influence on perception, emotion, and cognition, largely through the direct modulation of neural oscillations. Here, we synthesize these findings to motivate a new predictive coding model of respiratory brain coupling, in which breathing rhythmically modulates both local and global neural gain, to optimize cognitive and affective processing. Our model further explains how respiratory rhythms interact with the topology of the functional connectome, and we highlight key implications for the computational psychiatry of disordered respiratory and interoceptive inference. [ABSTRACT FROM AUTHOR]

Este trabajo explora en qué medida las características rítmicas de los textos poéticos pueden contribuir al reconocimiento de la autoría. Se demuestra, en primer lugar, que una categorización de las lenguas como silábicas o silábico-acentuales no explica completamente las diferencias. Sin embargo, nuestros análisis muestran que, si la regularidad acentual se formaliza como una continuidad, el reconocimiento de autoría mejora cuando pasamos de las lenguas más regularmente acentuadas a las menos. Los resultados apoyan la hipótesis según la cual la regularidad acentual es un factor inhibidor en el reconocimiento de autoría si se le considera como una característica continua. [ABSTRACT FROM AUTHOR]

A comparative analysis of heart rate variability (HRV) indices after injection of the acetylcholinesterase inhibitor (AChE) physostigmine (3/4 LD50) and the T-type calcium channel blocker (T-VDCC) Ni2+ (ED100) into animals was performed in experiments on 3-day-old newborn rats. Both drugs cause phenomenologically similar pathological heart rhythm with significant bradycardia complexes (PHRBC). Analysis of HRV indices showed that the disturbance of heart rhythm regulation mechanisms in NiCl2 poisoning of rats and in cholinoreactive structure activation caused by AChE inhibition develop according to a similar pattern. In both cases there is a decrease in the total power of the spectrum and the absolute power values of the LF (predominantly sympathetic) and HF (parasympathetic influences) bands. Significant decrease in the level of nerve influences leads to the fact that the dominant role in the regulation of heart rhythm begins to play neurohumoral factors (VLF-band). It was found that under conditions of premedication with N- or M-cholinolytics, when rats do not develop cardiac rhythm disturbances, the initial decrease in the severity of neurohumoral and subsequent increase in sympathetic and, to a lesser extent, parasympathetic influences is common. In this case, vagosympathetic balance is not decisive. In case the influence of neurohumoral factors increases after premedication, then later there is a decrease in the proportion of nerve influences and the occurrence of PHRBC. The obtained data suggest that in newborn rats both direct blockade of T-VDCC and changes in ICaT current mediated through M3-subtype muscarinic cholinoreceptors lead to disruption of pacing and development of PHRBC. [ABSTRACT FROM AUTHOR]

The ground reaction force (GRF) recorded by a platform when a person stands upright lies at the interface between the neural networks controlling stance and the body sway deduced from centre of pressure (CoP) displacement. It can be decomposed into vertical (VGRF) and horizontal (HGRF) vectors. Few studies have addressed the modulation of the GRFs by the sensory conditions and their relationship with body sway. We reconsidered the features of the GRFs oscillations in healthy young subjects (n = 24) standing for 90 s, with the aim of characterising the possible effects of vision, support surface and adaptation to repeated trials, and the correspondence between HGRF and CoP time-series. We compared the frequency spectra of these variables with eyes open or closed on solid support surface (EOS, ECS) and on foam (EOF, ECF). All stance trials were repeated in a sequence of eight. Conditions were randomised across different days. The oscillations of the VGRF, HGRF and CoP differed between each other, as per the dominant frequency of their spectra (around 4 Hz, 0.8 Hz and <0.4 Hz, respectively) featuring a low-pass filter effect from VGRF to HGRF to CoP. GRF frequencies hardly changed as a function of the experimental conditions, including adaptation. CoP frequencies diminished to <0.2 Hz when vision was available on hard support surface. Amplitudes of both GRFs and CoP oscillations decreased in the order ECF > EOF > ECS ≈ EOS. Adaptation had no effect except in ECF condition. Specific rhythms of the GRFs do not transfer to the CoP frequency, whereas the magnitude of the forces acting on the ground ultimately determines body sway. The discrepancies in the time-series of the HGRF and CoP oscillations confirm that the body's oscillation mode cannot be dictated by the inverted pendulum model in any experimental conditions. The findings emphasise the robustness of the VGRF "postural rhythm" and its correspondence with the cortical theta rhythm, shed new insight on current principles of balance control and on understanding of upright stance in healthy and elderly people as well as on injury prevention and rehabilitation. [ABSTRACT FROM AUTHOR]

The purpose of this study was to examine the development and characteristics of invented notation for musical representation. A total of 168 young children aged 3, 4 and 5 years participated in this study. The children listened to rhythm and melody, which represented music, to reveal their use of invented notation. The Korean children used various types of invented notation involving figures, numbers, Hangeul (Korean letters), lines, and mixed forms. The level of invented notation increased with age, similar to other kinds of representation competence. The level of invented notation was clearly and significantly higher when paper and drawing tools were used than when blocks were used. However, there was no significant difference in invented notation according to the type of music played (voice or instrument). This study suggests that providing children with various examples of musical experiences and representations as well as tools allows them to perform free and immediate representation without requiring dual representation. Additionally, the findings confirmed that Hangeul has an advantage in children's musical representation. [ABSTRACT FROM AUTHOR]

The amount of living space we have access to is one manifestation of the unequal distribution of housing resources within societies. The COVID-19 pandemic has required most households to spend more time at home, unmasking inequalities and reigniting longstanding debates about the functionality and experience of smaller homes. Drawing on interviews across three UK cities, this article attends to the changing household routines of individuals living in different types of small home, exploring daily life before and during 'lockdown'. Using the concept of urban rhythms, the data show that the lockdown has intensified existing pressures of living in a smaller home – lack of space for different functions and household members – whilst constraining coping strategies, like spending time outside the home. Lockdown restrictions governing mobility and contact acted as a mechanism of exception, disrupting habitual patterns of life and sociability, and forcing people to spend more time in smaller homes that struggled to accommodate different functions, affecting home atmospheres. For some, the loss of normal strategies was so significant that they sought to challenge the new rules governing daily life to protect their wellbeing. [ABSTRACT FROM AUTHOR]

The article focuses on J. R. R. Tolkien's essay "On Translating Beowulf" and its metrical appendix, which he claims to be a "novel plan" demonstrating rhythms of Old English poetry using examples in Modern English. Topics discussed include Tolkien's claim of precedence despite C. S. Lewis having a similar metrical essay five years earlier, the backstory of Tolkien's essay's development over fifteen years, and the influence of Lewis's 1939 book "Rehabilitations" as a motivating factor.

Even before the sinoatrial node (SAN) was discovered, cardiovascular science was engaged in an active investigation of when and why the heart would beat. After the electrochemical theory of bioelectric membrane potentials was formulated and the first action potentials were measured in contracting muscle cells, the field became divided: some investigators studied electrophysiology and ion channels, others studied muscle contraction. It later became known that changes in intracellular Ca2+ cause contraction. The pacemaking field was reunited by the coupled-clock theory of pacemaker cell function, which integrated intracellular Ca2+ cycling and transmembrane voltage into one rhythmogenic system. In this review, we will discuss recent discoveries that contextualize the coupled-clock system, first described in isolated SAN cells, into the complex world of SAN tissue: heterogeneous local Ca2+ releases, generated within SAN pacemaker cells and regulated by the other cell types within the SAN cytoarchitecture, variably co-localize and synchronize to give rise to relatively rhythmic impulses that emanate from the SAN to excite the heart. We will ultimately conceptualize the SAN as a brain-like structure, composed of intercommunicating meshworks of multiple types of pacemaker cells and interstitial cells, intertwined networks of nerves and glial cells and more. This article is part of the theme issue 'The heartbeat: its molecular basis and physiological mechanisms'. [ABSTRACT FROM AUTHOR]

Although, for many decades, the day–night rhythm in resting heart rate has been attributed to the parasympathetic branch of the autonomic nervous system (high vagal tone during sleep), recently we have shown that there is a circadian clock in the cardiac pacemaker, the sinus node, and the day–night rhythm in heart rate involves an intrinsic rhythmic transcriptional remodelling of pacemaker ion channels, particularly Hcn4. We have now investigated the role of the sympathetic branch of the autonomic nervous system in this and shown it to have a non-canonical role. In mice, sustained long-term block of cardiac β-adrenergic receptors by propranolol administered in the drinking water abolished the day–night rhythm in pacemaking in the isolated sinus node. Concomitant with this, there was a loss of the normal day–night rhythm in many pacemaker ion channel transcripts. However, there was little or no change in the local circadian clock, indicating that the well-known day–night rhythm in sympathetic nerve activity is directly involved in pacemaker ion channel transcription. The day–night rhythm in pacemaking helps explain the occurrence of clinically significant bradyarrhythmias during sleep, and this study improves our understanding of this pathology. This article is part of the theme issue 'The heartbeat: its molecular basis and physiological mechanisms'. [ABSTRACT FROM AUTHOR]

In the last 30 years, the field of cyclic adenosine 3′,5′-monophosphate (cAMP) signalling has witnessed a transformative development with the realization that cAMP is compartmentalized and that spatial regulation of cAMP is critical for faithful signal propagation and hormonal specificity. This recognition has changed our understanding of cAMP signalling from the canonical model, where a linear pathway connects a plasma membrane receptor to intracellular effectors and their targets, to a model where signal transduction occurs within a complex network of alternative branches and where an individual receptor leads to activation of a limited fraction of the network, enabled by local regulation of independent signalling units, resulting in a specific functional outcome. The cardiac myocyte has served as the cell model for many of the original findings leading to this paradigm. In this review, we cover some of the evidence supporting this new perspective and discuss how this model is providing novel mechanistic insight into cardiac myocyte physiology. With a focus on the regulation of cardiac rhythm, we consider how this model can provide an original framework for the identification of disease mechanisms. This article is part of the theme issue 'The heartbeat: its molecular basis and physiological mechanisms'. [ABSTRACT FROM AUTHOR]

Silvio Weidmann laid the basis of cardiac electrophysiology and was the forerunner in the search for mechanisms governing the electrical activity of the heart in his legendary first studies of Purkinje fibres in the 1950s. His work was the cornerstone of research in this field for many generations, and countless cardiologists and electrophysiologists have based their studies on the knowledge generated by Weidmann's pioneering data. This review summarizes his key contributions from the first intracellular recordings of cardiac membrane potentials in 1949 to the publication of his monograph in 1956. That summary is followed by an imagined dialogue between the authors and Silvio Weidmann himself, in the format of a one-act play. Both of us have such good recollections of our real-life conversations with Silvio Weidmann that we decided we could achieve a better feel for the history and issues by using a dialogue format. We hope that, in that way, we may transmit the character of Silvio Weidmann better for those readers who will not have known him personally. Silvio Weidmann was an extraordinarily sensitive and conversational person as well as a great scientist, and we feel it is worth the effort to convey that fact here. This article is part of the theme issue 'The heartbeat: its molecular basis and physiological mechanisms'. [ABSTRACT FROM AUTHOR]

When it comes to aging, some colonial invertebrates present disparate patterns from the customary aging phenomenon in unitary organisms, where a single senescence phenomenon along ontogeny culminates in their inevitable deaths. Here we studied aging processes in 81 colonies of the marine urochordate Botryllus schlosseri each followed from birth to death (over 720 days). The colonies were divided between three life history strategies, each distinct from the others based on the presence/absence of colonial fission: NF (no fission), FA (fission develops after the colony reaches maximal size), and FB (fission develops before the colony reaches maximal size). The study revealed recurring patterns in sexual reproductive statuses (hermaphroditism and male-only settings), colonial vigor, and size. These recurring patterns, collectively referred to as an Orshina, with one or more 'astogenic segments' on the genotype level. The combination of these segments forms the Orshina rhythm. Each Orshina segment lasts about three months (equivalent to 13 blastogenic cycles), and concludes with either the colonial death or rejuvenation, and is manipulated by absence/existing of fission events in NF/FA/FB strategies. These findings indicate that reproduction, life span, death, rejuvenation and fission events are important scheduled biological components in the constructed Orshina rhythm, a novel aging phenomenon. [ABSTRACT FROM AUTHOR]

Patients with hypertrophic cardiomyopathy (HCM) are at increased risk of stroke, but the incidence and factors associated with cardioembolic events in HCM patients without atrial fibrillation (AF) remain unresolved. We determined the incidence of stroke in patients in sinus rhythm (SR) monitored with a cardiac implantable electronic device (CIED). All consecutive patients diagnosed with HCM and referred to CIED implantation with >16 years at diagnosis and ≥ 1 year follow-up post CIED implantation were retrospectively reviewed. Severe LA dilatation was defined as ≥48 mm. Patients were stratified by rhythm as: Pre-existing AF (AF present prior to CIED); De novo AF (AF present after CIED implantation); SR : no episodes of AF. Of 1651 patients, 185 (11.2%) implanted with a CIED were included (57% men, age: 54 ± 17 years). Baseline, pre-existing AF was present in 73 (39%) patients. Ischemic stroke was reported in 19 (10.3%, 1.78%/year) patients and was similar across the three groups (2.3%/year vs 1.1%/year vs 0.6%/year in patients in SR vs pre-existing AF vs de novo AF , respectively, p = 0.235). In SR patients, a LAD≥48 mm posed the greatest risk of stroke (Hazard Ratio: 10.03,95% Confidence-Interval 2.79–16.01). At Cox multivariable analysis, after adjustment for oral anticoagulation, LA was independently associated with stroke while rhythm was not. in HCM patients with CIED long-term monitoring and no prior history of AF, stroke rates were similar in those with de novo AF or stable SR. Severe LA dilatation was a powerful risk factor, irrespective of AF. CIED: Cardiac Implantable Electronic Device, HCM: Hypertrophic Cardiomyopathy, HR: Hazard Ratio, P/LP pathogenic/likely pathogenic variant. [Display omitted] • Incidence of cardioembolic events in HCM patients with atrial fibrillation (AF) and sinus rhythm (SR) remains unresolved. • Whether left atrial (LA) disease could predispose to cardioembolic events in patients with SR is undetermined. • In patients with HCM and long-term monitoring stroke rates were similar in those with AF and SR. LA dilatation was a powerful risk factor. [ABSTRACT FROM AUTHOR]

Both the cerebellum and basal ganglia are involved in rhythm processing, but their specific roles remain unclear. During rhythm perception, these areas may be processing purely sensory information, or they may be involved in motor preparation, as periodic stimuli often induce synchronized movements. Previous studies have shown that neurons in the cerebellar dentate nucleus and the caudate nucleus exhibit periodic activity when the animals prepare to respond to the random omission of regularly repeated visual stimuli. To detect stimulus omission, the animals need to learn the stimulus tempo and predict the timing of the next stimulus. The present study demonstrates that neuronal activity in the cerebellum is modulated by the location of the repeated stimulus and that in the striatum (STR) by the direction of planned movement. However, in both brain regions, neuronal activity during movement and the effect of electrical stimulation immediately before stimulus omission were largely dependent on the direction of movement. These results suggest that, during rhythm processing, the cerebellum is involved in multiple stages from sensory prediction to motor control, while the STR consistently plays a role in motor preparation. Thus, internalized rhythms without movement are maintained as periodic neuronal activity, with the cerebellum and STR preferring sensory and motor representations, respectively. [ABSTRACT FROM AUTHOR]

Background: This study aims to investigate the effect of a course of selected corrective exercises on posture, scapula-humeral rhythm and performance of adolescent volleyball players. Methods: 30 adolescent volleyball players with upper cross syndrome were purposefully selected and assigned into 2 control and training groups. The degree of back curvature was evaluated using a flexible ruler, forward head and forward shoulder size by photographic method, scapula-humeral rhythm by Lateral Scapular Slide Test (LSST), and performance by closed kinetic chain test. The training group performed the exercises for 10 weeks. After the exercises, the post-test was administered. To analyze the data, analysis of co-variance tests and paired t-test at the level of 0.05 were employed. Results: The research results showed that corrective exercises have a significant effect on abnormalities of forward head, forward shoulder, kyphosis, scapula-humeral rhythm and performance. Conclusions: Corrective exercises can be effective in reducing shoulder girdle and spine abnormalities and improving scapula- humeral rhythm and performance of volleyball players. [ABSTRACT FROM AUTHOR]

Neural oscillations are thought to support speech and language processing. They may not only inherit acoustic rhythms, but might also impose endogenous rhythms onto processing. In support of this, we here report that human (both male and female) eye movements during naturalistic reading exhibit rhythmic patterns that show frequency-selective coherence with the EEG, in the absence of any stimulation rhythm. Periodicity was observed in two distinct frequency bands: First, wordlocked saccades at 4-5 Hz display coherence with whole-head theta-band activity. Second, fixation durations fluctuate rhythmically at ~1 Hz, in coherence with occipital delta-band activity. This latter effect was additionally phase-locked to sentence endings, suggesting a relationship with the formation of multi-word chunks. Together, eye movements during reading contain rhythmic patterns that occur in synchrony with oscillatory brain activity. This suggests that linguistic processing imposes preferred processing time scales onto reading, largely independent of actual physical rhythms in the stimulus. [ABSTRACT FROM AUTHOR]

It is well-known that chemotherapy brings about various adverse physical effects such as fatigue, nausea, or vomiting, and that it lowers mental well-being. It is less known that it desynchronizes patients with social environment. This study explores the temporal aspects and challenges of chemotherapy. Three groups equal in size and distinguished according to weekly, biweekly, and triweekly treatment schemes, each independently representative in terms of sex and age of the cancer population (total N = 440) were compared. The study found that chemotherapy sessions, regardless of their frequency, patients' age, and the overall length of treatment, have a very large effect on changing the felt pace of time from flying to dragging (Cohen's d = 1.6655). Most patients pay more attention to the passing of time than before treatment (59.3%), which has to do with the disease (77.4%). They also experience the loss of control over time, which they subsequently attempt to regain. The patients' actual activities before and after chemotherapy, however, are mostly the same. All these aspects create a unique 'chemo-rhythm', in which the significance of the type of cancer and demographic variables is negligible, and the mere rhythmic nature of treatment plays a central role. In conclusion, patients find the 'chemo-rhythm' stressful, unpleasant and difficult to control. It is vital to prepare them for it and help to reduce its adverse effects. [ABSTRACT FROM AUTHOR]

Disruption of circadian rhythms, such as shift work and jet lag, are associated with negative physiological and behavioral outcomes, including changes in affective state, learning and memory, and cognitive function. The prefrontal cortex (PFC) is heavily involved in all of these processes. Many PFC-associated behaviors are time-of-day dependent, and disruption of daily rhythms negatively impacts these behavioral outputs. Yet how disruption of daily rhythms impacts the fundamental function of PFC neurons, and the mechanism(s) by which this occurs, remains unknown. Using a mouse model, we demonstrate that the activity and action potential dynamics of prelimbic PFC neurons are regulated by time-of-day in a sex specific manner. Further, we show that postsynaptic K+ channels play a central role in physiological rhythms, suggesting an intrinsic gating mechanism mediating physiological activity. Finally, we demonstrate that environmental circadian desynchronization alters the intrinsic functioning of these neurons independent of time-of-day. These key discoveries demonstrate that daily rhythms contribute to the mechanisms underlying the essential physiology of PFC circuits and provide potential mechanisms by which circadian disruption may impact the fundamental properties of neurons. [ABSTRACT FROM AUTHOR]