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Purpose: Moderate-intensity aerobic exercise is safe and beneficial in atrial fibrillation (AF) and coronary heart disease (CHD). Irregular or rapid heart rates (HR) in AF and other heart conditions create a challenge to using HR to monitor exercise intensity. The purpose of this study was to assess the potential of breathing frequency (BF) to monitor exercise intensity in people with AF and CHD without AF. Methods: This observational study included 30 AF participants (19 Male, 70.7 ± 8.7 yrs) and 67 non-AF CHD participants (38 Male, 56.9 ± 11.4 yrs). All performed an incremental maximal exercise test with pulmonary gas exchange. Results: Peak aerobic power in AF ( V ˙ O2peak; 17.8 ± 5.0 ml.kg−1.min−1) was lower than in CHD (26.7 ml.kg−1.min−1) (p <.001). BF responses in AF and CHD were similar (BF peak: AF 34.6 ± 5.4 and CHD 36.5 ± 5.0 breaths.min−1; p =.106); at the 1st ventilatory threshold (BF@VT-1: AF 23.2 ± 4.6; CHD 22.4 ± 4.6 breaths.min−1; p =.240). % V ˙ O2peak at VT-1 were similar in AF and CHD (AF: 59%; CHD: 57%; p =.656). Conclusion: With the use of wearable technologies on the rise, that now include BF, this first study provides an encouraging potential for BF to be used in AF and CHD. As the supporting data are based on incremental ramp protocol results, further research is required to assess BF validity to manage exercise intensity during longer bouts of exercise. [ABSTRACT FROM AUTHOR]

Aircraft pilots face a high mental workload (MW) under environmental constraints induced by high altitude and sometimes sleep restriction (SR). Our aim was to assess the combined effects of hypoxia and sleep restriction on cognitive and physiological responses to different MW levels using the Multi-Attribute Test Battery (MATB)-II with an additional auditory Oddball-like task. Seventeen healthy subjects were subjected in random order to three 12-min periods of increased MW level (low, medium, and high): sleep restriction (SR, <3 h of total sleep time (TST)) vs. habitual sleep (HS, >6 h TST), hypoxia (HY, 2 h, FIO2 = 13.6%, ~3500 m vs. normoxia, NO, FIO2 = 21%). Following each MW level, participants completed the NASA-TLX subjective MW scale. Increasing MW decreases performance on the MATB-II Tracking task (p = 0.001, MW difficulty main effect) and increases NASA-TLX (p = 0.001). In the combined HY/SR condition, MATB-II performance was lower, and the NASA-TLX score was higher compared with the NO/HS condition, while no effect of hypoxia alone was observed. In the accuracy of the auditory task, there is a significant interaction between hypoxia and MW difficulty (F(2–176) = 3.14, p = 0.04), with lower values at high MW under hypoxic conditions. Breathing rate, pupil size, and amplitude of pupil dilation response (PDR) to auditory stimuli are associated with increased MW. These parameters are the best predictors of increased MW, independently of physiological constraints. Adding ECG, SpO2, or electrodermal conductance does not improve model performance. In conclusion, hypoxia and sleep restriction have an additive effect on MW. Physiological and electrophysiological responses must be taken into account when designing a MW predictive model and cross-validation. [ABSTRACT FROM AUTHOR]

This paper introduces and evaluates an innovative sensor for unobtrusive in-car respiration monitoring, mounted on the backrest of the driver's seat. The sensor seamlessly integrates into the vehicle, measuring breathing rates continuously without requiring active participation from the driver. The paper proves the feasibility of unobtrusive in-car measurements over long periods of time. Operation of the sensor was investigated over 12 participants sitting in the driver seat. A total of 107 min of driving in diverse conditions with overall coverage rate of 84.45% underscores the sensor potential to reliably capture physiological changes in breathing rate for fatigue and stress detection. [ABSTRACT FROM AUTHOR]

Vital sign monitoring is dominated by precise but costly contact-based sensors. Contactless devices such as radars provide a promising alternative. In this article, the effects of lateral radar positions on breathing and heartbeat extraction are evaluated based on a sleep study. A lateral radar position is a radar placement from which multiple human body zones are mapped onto different radar range sections. These body zones can be used to extract breathing and heartbeat motions independently from one another via these different range sections. Radars were positioned above the bed as a conventional approach and on a bedside table as well as at the foot end of the bed as lateral positions. These positions were evaluated based on six nights of sleep collected from healthy volunteers with polysomnography (PSG) as a reference system. For breathing extraction, comparable results were observed for all three radar positions. For heartbeat extraction, a higher level of agreement between the radar foot end position and the PSG was found. An example of the distinction between thoracic and abdominal breathing using a lateral radar position is shown. Lateral radar positions could lead to a more detailed analysis of movements along the body, with the potential for diagnostic applications. [ABSTRACT FROM AUTHOR]

Objectives: Chronic musculoskeletal pain is associated with decreased parasympathetic and increased sympathetic activity in the autonomic nervous system. The objective of this study was to determine the associations between objective measures of heart rate variability (a measure of autonomic nervous system function), actigraphy (a measure of activity and sleep quality), respiration rates, and subjective patient‐reported outcome measures (PROMs) of central sensitization, kinesiophobia, disability, the effect of pain on sleep, and life quality. Methods: Thirty‐eight study subjects were divided into two subgroups, including low symptoms of central sensitization (n = 18) and high symptoms of central sensitization (n = 20), based on patient‐reported scores on the Central Sensitization Inventory (CSI). Heart rate variability (HRV) and actigraphy measurements were carried out simultaneously in 24 h measurement during wakefulness and sleep. Results: A decrease in HRV during the first 2 h of sleep was stronger in the low CSI subgroup compared to the high CSI subgroup. Otherwise, all other HRV and actigraphy parameters and subjective measures of central sensitization, disability, kinesiophobia, the effect of pain on sleep, and quality of life showed only little associations. Discussion: The high CSI subgroup reported significantly more severe symptoms of disability, kinesiophobia, sleep, and quality of life compared to the low CSI subgroup. However, there were only small and nonsignificant trend in increased sympathetic nervous system activity and poorer sleep quality on the high central sensitization subgroup. Moreover, very little differences in respiratory rates were found between the groups. [ABSTRACT FROM AUTHOR]

Sleep regularity and chronotype can affect health, performance, and overall well-being. This observational study examines how sleep regularity and chronotype affect sleep quality and cardiorespiratory metrics. Data was collected from 1 January 2019 through 30 December 2019 from over 330 000 Sleep Number smart bed users across the United States who opted into this at-home study. A pressure signal from the smart bed reflected bed presence, movements, heart rate (HR), and breathing rate (BR). Participants (mean age: 55.69 years [SD: 14.0]; 51.2% female) were categorized by chronotype (16.8% early; 62.2% intermediate, 20.9% late) and regularity of sleep timing. Participants who were regular sleepers (66.1%) experienced higher percent restful sleep and lower mean HR and BR compared to the 4.8% categorized as irregular sleepers. Regular early-chronotype participants displayed better sleep and cardiorespiratory parameters compared to those with regular late-chronotypes. Significant variations were noted in sleep duration (Cohen's d = 1.54 and 0.88, respectively) and restful sleep (Cohen's d = 1.46 and 0.82, respectively) between early and late chronotypes, particularly within regular and irregular sleep patterns. This study highlights how sleep regularity and chronotype influence sleep quality and cardiorespiratory metrics. Irrespective of chronotype, sleep regularity demonstrated a substantial effect. Further research is necessary to confirm these findings. [ABSTRACT FROM AUTHOR]

Abnormalities in cardiorespiratory measurements have repeatedly been found in patients with panic disorder (PD) during laboratory-based assessments. However, recordings performed outside laboratory settings are required to test the ecological validity of these findings. Wearable devices, such as sensor-imbedded garments, biopatches, and smartwatches, are promising tools for this purpose. We systematically reviewed the evidence for wearables-based cardiorespiratory assessments in PD by searching for publications on the PubMed, PsycINFO, and Embase databases, from inception to 30 July 2022. After the screening of two-hundred and twenty records, eight studies were included. The limited number of available studies and critical aspects related to the uncertain reliability of wearables-based assessments, especially concerning respiration, prevented us from drawing conclusions about the cardiorespiratory function of patients with PD in daily life. We also present preliminary data on a pilot study conducted on volunteers at the Villa San Benedetto Menni Hospital for evaluating the accuracy of heart rate (HR) and breathing rate (BR) measurements by the wearable Zephyr BioPatch compared with the Quark-b2 stationary testing system. Our exploratory results suggested possible BR and HR misestimation by the wearable Zephyr BioPatch compared with the Quark-b2 system. Challenges of wearables-based cardiorespiratory assessment and possible solutions to improve their reliability and optimize their significant potential for the study of PD pathophysiology are presented. [ABSTRACT FROM AUTHOR]

Plant secondary metabolites in Tetrapleuratetraptera fruit meal (TTFM) could be exploited as natural safe feed additives alternative to non-nutritive chemical and antibiotics to enhance rumen fermentation and feed utilization efficiency with negative oxidative stress. The study investigated the responses of West African Dwarf (WAD) rams to the diets containing varying levels of supplemental Tetrapleura tetraptera fruit meal on the oxidative status and thermo-physiological parameters. Thirty five (35) WAD rams with an average live weight of 13.20±0.2 kg were used in a completely randomized design for 140 days. Five concentrate diets containing varying levels (0, 0.5, 1.0, 1.5 and 2.0 %) of TTFM were formulated while Panicum maximum was fed as a basal diet. The rectal temperature, pulse rate and respiratory rate were measured at two week intervals while blood was collected through jugular veins at the onset and at the end of feeding trial to determine oxidative status parameters in terms of superoxide dismutase (SOD), glutathione peroxidase, thiobarbituric acid reactive substance (TBARS). Data collected were subjected to one way Analysis of Variance (ANOVA). No significant difference observed (p>0.05) in the rectal temperature while the pulse rate and breathing rate increased significantly (p<0.05) till 12th week of the experiment. Increased glutathione peroxidase, superoxide dismutase and lowered thiobarbituric acid reactive substance were recorded on the rams at the end of the feeding trial. It was therefore concluded that inclusion of Tetrapleura tetraptera up to 2 % level reduced the oxidative stress in the experimental animals coupled with better thermo-physiological responses. [ABSTRACT FROM AUTHOR]

The emotional reactions to social exclusion can be associated with physiological responses that could allow researchers to estimate the valence and intensity of the ongoing affective state. In this work, respiratory activity was analysed to verify whether breathing rate variations can be considered as predictive factors of subsequent positive and negative affect after inclusion and exclusion in young women. A standard Cyberball task was implemented and manipulated information was provided to the participants to create both conditions. The participants were socially excluded by limiting their participation to 6% of the total number of passes among three teammates and providing negative feedback about them. The results suggest that breathing rate can be a good option to infer subjective feelings during social interactions and a promising feature to incorporate into modern emotion monitoring systems as an alternative to other physiological measures. Furthermore, the interaction between metaemotion and physiology was studied by recording breathing rate while completing the Positive and Negative Affect Schedule, evidencing a breathing rate increase during the emotion self-assessment only after exclusion. [ABSTRACT FROM AUTHOR]

Competitive indoor climbing has increased in popularity at the youth, collegiate, and Olympic levels. A critical aspect for improving performance is characterizing the physiologic response to different climbing strategies (e.g., work/rest patterns, pacing) and techniques (e.g., body position and movement) relative to location on climbing wall with spatially varying characteristics (e.g., wall inclinations, position of foot/hand holds). However, this response is not well understood due to the limited capabilities of climbing-specific measurement and assessment tools. In this study, we developed a novel method to examine time-resolved sensor-based measurements of multiple personal biometrics at different microlocations (finely spaced positions; MLs) along a climbing route. For the ML-specific biometric system (MLBS), we integrated continuous data from wearable biometric sensors and smartphone-based video during climbing, with a customized visualization and analysis system to determine three physiologic parameters (heart rate, breathing rate, ventilation rate) and one body movement parameter (hip acceleration), which are automatically time-matched to the corresponding video frame to determine ML-specific biometrics. Key features include: (1) biometric sensors that are seamlessly embedded in the fabric of an athletic compression shirt, and do not interfere with climbing performance, (2) climbing video, and (3) an interactive graphical user interface to rapidly visualize and analyze the time-matched biometrics and climbing video, determine timing sequence between the biometrics at key events, and calculate summary statistics. To demonstrate the capabilities of MLBS, we examined the relationship between changes in ML-specific climbing characteristics and changes in the physiologic parameters. Our study demonstrates the ability of MLBS to determine multiple time-resolved biometrics at different MLs, in support of developing and assessing different climbing strategies and training methods to help improve performance. [ABSTRACT FROM AUTHOR]

Objective: Increased understanding of the role of cortical structures in respiratory control may help the understanding of seizure‐induced respiratory dysfunction that leads to sudden unexpected death in epilepsy (SUDEP). The aim of this study was to characterize respiratory responses to electrical stimulation (ES), including inhibition and enhancement of respiration. Methods: We prospectively recruited 19 consecutive patients with intractable epilepsy undergoing stereotactic electroencephalography (EEG) evaluation from June 2015 to June 2018. Inclusion criteria were patients ≥18 years in whom ES was indicated for clinical mapping of ictal onset or eloquent cortex as part of the presurgical evaluation. ES was carried out at 50 Hz, 0.2 msec, and 1–10 mA current intensity. Common brain regions sampled across all patients were amygdala (AMY), hippocampus (HG), anterior cingulate gyrus (CING), orbitofrontal cortex (OrbF), temporal neocortex (TNC), temporal pole (TP), and entorhinal cortex (ERC). Seven hundred fifty‐five stimulations were conducted. Quantitative analysis of breathing signal, that is, changes in breathing rate (BR), depth (TV), and minute ventilation (MV), was carried out during ES using the BreathMetrics breathing waveform analysis toolbox. Electrocardiography, arterial oxygen saturation, end‐tidal and transcutaneous carbon dioxide, nasal airflow, and abdominal and thoracic plethysmography were monitored continuously during stimulations. Results: Electrical stimulation of TP and CING (at lower current strengths <3 mA) increased TV and MV. At >7‐10 mA, CING decreased TV and MV. On the other hand, decreased TV and MV occurred with stimulation of mesial temporal structures such as AMY and HG. Breathing changes were dependent on stimulation intensity. Lateral temporal, entorhinal, and orbitofrontal cortices did not affect breathing either way. Significance: These findings suggest that breathing responses other than apnea can be induced by ES. Identification of two regions—the temporal pole and anterior cingulate gyrus—for enhancement of breathing may be important in paving the way to future development of strategies for prevention of SUDEP. [ABSTRACT FROM AUTHOR]

Purpose: To determine how repeatable thoracoabdominal compartmental contributions to tidal volume (VT) are across different intensities of exercise, and to examine if the pattern of breathing for a given minute ventilation (V̇E) is reproducible between constant-load and ramp exercise tests. Methods: Ten healthy adults (age: 27 ± 6 yr, peak oxygen uptake: 42 ± 5 mL min−1 kg−1) completed a 25 W·min−1 ramp cycling test to exhaustion and two repetitions of a step cycling test on separate days. VT, breathing rate (BR), and V̇E were assessed using a bi-directional turbine, and thoracic and abdominal contributions to VT were measured using respiratory inductance plethysmography. Repeatability (step vs. step) and reproducibility (step vs. ramp) of responses were assessed using the intra-class correlation coefficient (ICC). Results: The relative compartment contributions to VT during step exercise were highly repeatable for low (ICC = 0.87, p = 0.003), moderate (ICC = 0.89, p = 0.002) and heavy (ICC = 0.93, p = 0.001) exercise. Inter-individual differences in response to higher intensity exercise were observed, as two participants had significant relationships between VT and their percent compartmental contributions to VT, but five others did not. No differences were identified between ramp and step exercise tests for VT (main effect: p = 0.61) or BR (main effect: p = 0.77) at matched V̇E for each intensity, and the pattern of breathing was reproducible for each intensity. Conclusion: These findings suggest the way young healthy adults breathe for a given V̇E is repeatable day-to-day and reproducible between different exercise protocols. [ABSTRACT FROM AUTHOR]

The Sleep Number smart bed uses embedded ballistocardiography, together with network connectivity, signal processing, and machine learning, to detect heart rate (HR), breathing rate (BR), and sleep vs. wake states. This study evaluated the performance of the smart bed relative to polysomnography (PSG) in estimating epoch-by-epoch HR, BR, sleep vs. wake, mean overnight HR and BR, and summary sleep variables. Forty-five participants (aged 22–64 years; 55% women) slept one night on the smart bed with standard PSG. Smart bed data were compared to PSG by Bland–Altman analysis and Pearson correlation for epoch-by-epoch HR and epoch-by-epoch BR. Agreement in sleep vs. wake classification was quantified using Cohen's kappa, ROC analysis, sensitivity, specificity, accuracy, and precision. Epoch-by-epoch HR and BR were highly correlated with PSG (HR: r = 0.81, |bias| = 0.23 beats/min; BR: r = 0.71, |bias| = 0.08 breaths/min), as were estimations of mean overnight HR and BR (HR: r = 0.94, |bias| = 0.15 beats/min; BR: r = 0.96, |bias| = 0.09 breaths/min). Calculated agreement for sleep vs. wake detection included kappa (prevalence and bias-adjusted) = 0.74 ± 0.11, AUC = 0.86, sensitivity = 0.94 ± 0.05, specificity = 0.48 ± 0.18, accuracy = 0.86 ± 0.11, and precision = 0.90 ± 0.06. For all-night summary variables, agreement was moderate to strong. Overall, the findings suggest that the Sleep Number smart bed may provide reliable metrics to unobtrusively characterize human sleep under real life-conditions. [ABSTRACT FROM AUTHOR]

Breathing rate is considered one of the fundamental vital signs and a highly informative indicator of physiological state. Given that the monitoring of heart activity is less complex than the monitoring of breathing, a variety of algorithms have been developed to estimate breathing activity from heart activity. However, estimating breathing rate from heart activity outside of laboratory conditions is still a challenge. The challenge is even greater when new wearable devices with novel sensor placements are being used. In this paper, we present a novel algorithm for breathing rate estimation from photoplethysmography (PPG) data acquired from a head-worn virtual reality mask equipped with a PPG sensor placed on the forehead of a subject. The algorithm is based on advanced signal processing and machine learning techniques and includes a novel quality assessment and motion artifacts removal procedure. The proposed algorithm is evaluated and compared to existing approaches from the related work using two separate datasets that contains data from a total of 37 subjects overall. Numerous experiments show that the proposed algorithm outperforms the compared algorithms, achieving a mean absolute error of 1.38 breaths per minute and a Pearson's correlation coefficient of 0.86. These results indicate that reliable estimation of breathing rate is possible based on PPG data acquired from a head-worn device. [ABSTRACT FROM AUTHOR]

The article focuses on the study to assess different high-frequency (HF) band power calculations based on different frequency bandwidth values, and compare them with the time domain the root mean square of successive RR differences (RMSSD) value in preterm infants. It mentions that the RMSSD was highly and positively correlated with frequency bands that were based on each preterms BR range, or on a constant frequency with band limits of 0.4–2 Hz.

We hypothesize that recent (2017) changes in competition rules significantly affected kinematic (mechanical activity) and physiological (cardiopulmonary indices and lactate concentration) profile of the taekwondo combat, which is currently becoming more demanding in terms of exercise intensity and fatigue. Twenty two male and female elite taekwondo athletes were followed up for over 2 years. In total, 258 real tournament combats were included in the analysis (133 in old rules and 125 in new rules). Kinematic and physiological characteristics were recorded using a biomonitor (BioHarness 3; Zephyr Technologies) worn by athletes during tournaments. Blood samples were drawn after each combat for lactate concentration. Our research showed that recent amendments of competition rules were linked to a noticeable shift toward higher kinematic output and, consequently, increased physiological response. Significant increments in kinematic variables (3-8%), heart rate (HR) (1.5-1.8%), energy expenditure (EE) (3-5%), overall physiological load (2-4%), and lactate concentration (~15% immediately after exercise and ~25% in recovery) suggest that new rules are more demanding, although the statistical effect size is only small or moderate. In conclusion, after competition rule changes, there has been a shift in taekwondo combat profile toward greater body movement dynamics, higher intensity, and greater postexercise fatigue. The values of key indices of exercise response (mechanical activity, HR, EE, and lactate concentration) during tournaments are near or exceeding the maximum attained during progressive exercise until exhaustion. Therefore, more focus is needed on taekwondo-specific high-intensity training and post-combat recovery to adapt athletes to increased competition requirements. [ABSTRACT FROM AUTHOR]

To understand the growing needs of an aging human population, there is demand for scalable and reproducible approaches to study animal models of aging and to test novel therapeutic interventions. We investigated the sensitivity and utility of a continuous monitoring platform and its digital biomarkers (motion, breathing rate, and wheel running) to evaluate behavioral and physiological differences between "young" (12 weeks) and "old" (23 months) male C57BL/6J mice with or without running wheels in the home cage. Compared to young mice, old mice showed marked reductions in motion and breathing rate, as well as altered circadian rhythms. Mice without running wheels possessed lower breathing rates compared to their counterparts with running wheels. Digital biomarkers showed age-dependent changes in response to routine procedures (cage changes and blood sampling) and alterations in subjects that unexpectedly reached endpoint. Continuous collection of digital biomarkers in the home cage can enhance current approaches by providing unbiased longitudinal monitoring for large-scale aging studies. [ABSTRACT FROM AUTHOR]

Sexual conflict over parental investment is widespread among species with biparental care. Studies have indicated that a high degree of behavioural similarity between the two parents can increase offspring survival; however, it remains unclear how sexual conflict over parental care is resolved. In this study, we examined whether similarity of personality traits between the two parents plays an important role in affecting the provisioning behaviour of each sex in a wild population of the chestnut thrush, Turdus rubrocanus. First, as expected, the mating pairs with more similar personality traits had higher provisioning rates than those pairs with dissimilar traits. Moreover, we found that the similarity of personality traits can modulate the sexual conflict over provisioning in this species, as both parents with more similar partners had relatively higher and less divergent provisioning rates. A partner removal experiment revealed how the sole female or male parent responded when the level of conflict over care increased (the removed partner does not provide any care). The majority of males always reduced their provisioning investment, while females' decisions depended on the degree of similarity with their partners. Females compensated by provisioning more frequently in pairs of similar personality traits (i.e. accepting a high level of conflict), but reduced their provisioning investment in extremely dissimilar pairs. Our results promote a better understanding of the resolution of sexual conflict over provisioning and highlight the evolutionary significance of mating with similar partners based on certain personality traits. • We studied personality and sexual conflict over provisioning in chestnut thrushes. • Pairs with more similar activity provisioned chicks at higher rates. • Pairs with more similar activity had less divergent provisioning rates. • Activity similarity affected provisioning rate of parent after partner removed. [ABSTRACT FROM AUTHOR]

In species that are subject to brood parasitism, individuals often vary in their responses to parasitic eggs, with some rejecting the eggs while others do not. While some factors, such as host age (breeding experience), the degree of egg matching and the level of perceived risk of brood parasitism have been shown to influence host decisions, much of the variation remains unexplained. The host personality hypothesis suggests that personality traits of the host influence its response to parasitic eggs, but few studies have tested this. We investigated the relationship between two personality traits (exploration and neophobia) and a physiological trait (breathing rate) of the host, and egg-rejection behaviour in a population of Daurian redstarts Phoenicurus auroreus in northeast China. We first show that exploratory behaviour and the response to a novel object are repeatable for individual females and strongly covary, indicating distinct personality types. We then show that fast-exploring and less neophobic hosts were more likely to reject parasitic eggs than slow-exploring and more neophobic hosts. Variation in breathing rate—a measure of the stress-response—did not affect rejection behaviour. Our results demonstrate that host personality, along the bold-shy continuum, predicts the responses to parasitic eggs in Daurian redstarts, with bold hosts being more likely to reject parasitic eggs. [ABSTRACT FROM AUTHOR]

Study Objectives: Unobtrusive monitoring of sleep and sleep disorders in children presents challenges. We investigated the possibility of using Ultra-Wide band (UWB) radar to measure sleep in children.Methods: Thirty-two children scheduled to undergo a clinical polysomnography participated; their ages ranged from 2 months to 14 years. During the polysomnography, the children's body movements and breathing rate were measured by an UWB-radar. A total of 38 features were calculated from the motion signals and breathing rate obtained from the raw radar signals. Adaptive boosting was used as machine learning classifier to estimate sleep stages, with polysomnography as gold standard method for comparison.Results: Data of all participants combined, this study achieved a Cohen's Kappa coefficient of 0.67 and an overall accuracy of 89.8% for wake and sleep classification, a Kappa of 0.47 and an accuracy of 72.9% for wake, rapid-eye-movement (REM) sleep, and non-REM sleep classification, and a Kappa of 0.43 and an accuracy of 58.0% for wake, REM sleep, light sleep and deep sleep classification.Conclusion: Although the current performance is not sufficient for clinical use yet, UWB radar is a promising method for non-contact sleep analysis in children. [ABSTRACT FROM AUTHOR]

In this study, a thermal imaging instrument was used to obtain facial thermal image information which was then used to calculate the number of breaths taken. However, small movements were inevitable and the first issue addressed was the means by which image calibration and region selection was to be made. To this end, thermal image sequence data calibration was done using technology that resolved small natural deviations in the nostril area. After these problems had been solved, a Hampel filter was used to process the nostril area signals. The independent component method was used to filter the effects of non‐respiratory signals, and the least squares method was employed for smoothing. Savitzky‐Golay filtering was used to adjust the signal baseline and the processed nostril region thermal image signals were compared with standard abdominal breathing band signals. Results showed that the difference in the number of breaths per minute was less than 1.5 times. The usual normal respiratory frequency range lies within a range of 0.1–0.5Hz. In the calculation of 'coherence obtained from MVAR model', the spectral coherence analysis results showed the methods proposed in this study can substantially enhance the relevance between 0.15 and 0.2Hz. [ABSTRACT FROM AUTHOR]

Objective: The objective of this paper is to obtain accurate estimation of breathing rate (BR), using only the electrocardiogram (ECG) or the photoplethysmogram (PPG) signals, to avoid wearing cumbersome and uncomfortable sensors for direct measurements. Methods: Several respiration waveforms are derived from ECG or PPG signals based on amplitude, frequency, and baseline wander modulations. It is, however, difficult to determine their optimal combination for BR estimation due to the noise and patient specificity. We first propose to quantify the quality of modulation waveforms using respiratory quality indices (RQIs). We then present two methods: the first automatically selects the modulation signal with highest RQI for BR estimation, and the second tracks the respiration signal using the Kalman smoother to fuse modulation signals with highest RQI. Results: These two methods are evaluated on two independent datasets, one benchmark database (DB) with immobilized patients recordings and the second with those performing daily activities. Our results outperform existing methods in the literature in both the cases. Conclusion: Experimental results show that the RQIs coupled with a fusion algorithm increases the accuracy for BR estimations in dealing with derived modulation signals. Significance: This work describes a robust Kalman Smoother method applicable in multiple clinical contexts to improve breathing rate estimation from data fusion. [ABSTRACT FROM AUTHOR]

Highlights • POF-embedded smart textile for breath and heart rates monitoring. • Analytical approach for the sensor operation principle. • Technique for detecting heart and breath rates even when the subject is moving. • Signal processing to mitigate the influence of gait frequency in the sensor response. Abstract In this paper, we present the development of a polymer optical fiber (POF) sensor for simultaneous measurement of breath (BR) and heart rates (HR). The sensor is embedded as a smart textile solution that can be used within the user’s clothes. In addition, a signal processing technique is proposed for obtaining the HR and BR without the influence of body movements and in different positions of the user’s chest. Sensor signal processing and analysis are made in the frequency domain and different filters are applied. Results show errors below 4 beats per minute and 2 breaths per minute for the HR and BR, respectively, even when the user is performing periodic body movements such as the ones induced by the gait. Thus, the proposed POF-based smart textile is a low-cost solution with good accuracy that can be readily applied in the remote monitoring of patients at home without disturbing their daily activities. [ABSTRACT FROM AUTHOR]

We develop and evaluate a respiratory rate (RR) estimation algorithm that utilizes data from the pressure-sensitive mat (PSM) technology for continuous patient monitoring in neonatal intensive care units. An analysis of the random effect of drift and systematic effect of creep in the PSM data is presented, showing that these are essentially dependent on the applied load and contact surface. Uncertainty measurements are pivotal when estimating physiologic parameters. The standard uncertainty in the PSM data is here represented by the percent drift. Next, we evaluate the applicability of the PSM technology to estimate RR in neonatal patient simulator trials under five mixed effects including internally and externally induced motion, mattress type, grunting, laying position, and different breathing rates. We analyze the limits of agreement on the mixed effects model to derive the uncertainty in the estimated RR obtained through two estimation techniques. In comparison with the gold standard RR values, we achieved a mean bias of 0.56 breaths per minute (bpm) with an error bounded by a 95% confidence interval of [−2.26, 3.37] bpm. These results meet the clinical accuracy requirements of RR within ±5 bpm. [ABSTRACT FROM AUTHOR]

Stocking density determines the welfare, growth performance, and even survival of aquatic organisms in aquaculture. However, how stocking density affects cephalopods are still unclear. Here we selected Amphioctopus fangsiao , a promising cephalopod for mariculture, to examine the effect of stocking density on survival, growth, physiology and behavior. Juvenile A. fangsiao (≈ two months post-hatch, 2.41 g ± 0.03) were reared for 21 days under different stocking density groups: 30, 45, 60 and 75 individual/m2 (ind./m2) (G1, G2, G3 and G4, respectively). Subsequently, the growth performance, aggressive acts, survival rate, stress response, oxidative stress and glucolipid metabolism were analyzed. This study showed that the high stocking density had a negative impact on growth performance. A. fangsiao reared in G3 and G4 had a significantly lower final body weight, weight gain and specific growth rate than those reared in G1 and G2 (p <.05), and hepatosomatic index in different treatment groups have a similar trend of difference (p <.05). Increased stocking density also caused more fights of A. fangsiao , resulting in a high mortality rate for farmed individuals. The individual numbers of released ink after touch and the recovery time of the breathing rate after air emersion showed that the low stocking density lowered the basal stress level and reduced the recovery time after acute stress of juvenile A. fangsiao. In addition, this study demonstrated that high stocking density has caused oxidative stress and lipid disturbance of A. fangsiao. There were significant differences in reactive oxygen species (ROS), lipid peroxidation's level (MDA content), the activities of superoxide dismutase (SOD) and catalase (CAT), pyruvic acid level (Pyr), total cholesterol level (T-CHO) and triglyceride (TG) between the highest density group (G4) and the lowest density group (G1). Overall, high stocking density (G3 and G4) had a negative effect on reared A. fangsiao. However, there were no significant differences between G1 and G2. Therefore, to improve the welfare of reared A. fangsiao and maximize the economic benefits for producers, juveniles are recommended to rear at a medium density (about 45 ind./m2). [Display omitted] • High stocking density reduced the growth performance and stress response in Amphioctopus fangsiao. • Increased stocking density caused more fights of A. fangsiao , resulting in a high mortality rate for farmed individuals. • High stocking density caused the oxidative stress and lipid disturbance of A. fangsiao. • The optimal stocking density in industrial aquaculture of A. fangsiao is about 45 octopuses/m2. [ABSTRACT FROM AUTHOR]

Animal personality has been linked to individual fitness across many taxa. However, the exact path by which personality translates into fitness is rarely identified. We tested whether nest site choice may serve as a potential pathway linking personality and reproductive success in a natural population of chestnut thrush, Turdus rubrocanus . Using path analysis, we found that human disturbance and choice of nest site with respect to nest density may both mediate the link between personality and reproductive success. Bolder females may choose nest sites with lower nest density, and the low nest density in turn may be responsible for a positive effect on nestling number, and have a negative effect on nestling mass. Bolder females may also prefer nest sites further from human settlements, resulting in a negative effect on nestling mass. Our findings provide rare exact mechanistic pathways by which boldness might be translated into reproductive success. [ABSTRACT FROM AUTHOR]

• Urban and rural animals are different in their behaviors and hormones (termed coping styles), but it is unknown when such differences arise in an animal's life. • We examine the development of coping styles in European starling nestlings (Sturnus vulgaris). • Nestling stress responses develop more rapidly in urban than rural birds after they pass their peak of growth, such that urban fledglings have elevated glucocorticoid stress responses compared to rural birds. • Behavior and hormones were only weakly correlated in rural birds, and uncorrelated in urban birds supporting the two-tiered model of coping styles. Urbanization is increasing globally and altering the stressors that animals face in their everyday lives. Organisms often differ in their coping styles—both behavioral and endocrine—across urban to rural habitats. For example, urban animals are often bolder, more exploratory, and mount stronger glucocorticoid stress responses compared to their rural counterparts. While these coping styles are important in shaping fitness across the urban-to-rural gradient, it remains unclear when these differences arise in the life of organisms. We explore the development of coping styles in European starling nestlings (Sturnus vulgaris), an urban-adapted species. We test whether breathing rate, handling struggle rate, and bag struggle rate differ across sites and find no difference in the behavioral coping styles of nestlings raised in urban versus rural sites. We also explore differences in baseline and stress-induced glucocorticoids, finding that urban nestlings develop a stronger stress response than rural birds before fledging the nest. We find no significant correlations between behavioral and endocrine traits for urban or rural birds, which supports the two-tiered model of coping styles. One possibility is that behavioral and endocrine differences develop at different times over the lives of organisms. Our findings support prior work suggesting that behavioral and endocrine coping mechanisms act independently of one another, and suggests that endocrine coping mechanisms develop in early life and before differences in behavioral coping styles might arise. Future work on the mechanisms leading to early-life differences in coping styles—from genetics to maternal effects to environmental effects—is needed to best predict how urban-adapted organisms cope with environmental change. Studies across a greater number of sites will help disentangle site from urbanization effects. [ABSTRACT FROM AUTHOR]

The present study determined whether EEG and/or EMG recordings could be used to reliably define activity states in the Brazilian black and white tegu lizard ( Tupinambis merianae) and then examined the interactive effects of temperature and activity states on strategies for matching O supply and demand. In a first series of experiments, the rate of oxygen consumption ( $$\dot{V}_{{{\text{O}}_{ 2} }}$$ ), breathing frequency ( f), heart rate ( f), and EEG and EMG (neck muscle) activity were measured in different sleep/wake states (sleeping, awake but quiet, alert, or moving). In general, metabolic and cardio-respiratory changes were better indictors of the transition from sleep to wake than were changes in the EEG and EMG. In a second series of experiments, the interactive effects of temperature (17, 27 and 37 °C) and activity states on f, tidal volume ( V), the fraction of oxygen extracted from the lung per breath (FI-FE), f, and the cardiac O pulse were quantified to determine the relative roles of each of these variables in accommodating changes in $$\dot{V}_{{{\text{O}}_{ 2} }}$$ . The increases in oxygen supply to meet temperature- and activity-induced increases in oxygen demand were produced almost exclusively by increases in f and f. Regression analysis showed that the effects of temperature and activity state on the relationships between f, f and $$\dot{V}_{{{\text{O}}_{ 2} }}$$ was to extend a common relationship along a single curve, rather than separate relationships for each metabolic state. For these lizards, the predictive powers of f and f were maximized when the effects of changes in temperature, digestive state and activity were pooled. However, the best r values obtained were 0.63 and 0.74 using f and f as predictors of met abolic rate, respectively. [ABSTRACT FROM AUTHOR]

We tested the validity of the Hexoskin wearable vest to monitor heart rate (HR), breathing rate (BR), tidal volume ( VT), minute ventilation, and hip motion intensity (HMI) in comparison with laboratory standard devices during lying, sitting, standing, and walking. Twenty healthy young volunteers participated in this study. First, participants walked 6 min on a treadmill at speeds of 1, 3, and 4.5 km/h followed by increasing treadmill grades until 80% of their predicted maximal heart rate. Second, lying, sitting, and standing tasks were performed (5 min each) followed by 6 min of treadmill walking at 80% of their ventilatory threshold. Analysis of each individual's mean values under each resting or exercise condition by the 2 measurement systems revealed low coefficient of variation and high intraclass correlation values for HR, BR, and HMI. The Bland-Altman results from HR, BR, and HMI indicated no deviation of the mean value from zero and relatively small variability about the mean. VT and minute ventilation were provided in arbitrary units by the Hexoskin device; however, relative magnitude of change from Hexoskin closely tracked the laboratory standard method. Hexoskin presented low variability, good agreement, and consistency. The Hexoskin wearable vest was a valid and consistent tool to monitor activities typical of daily living such as different body positions (lying, sitting, and standing) and various walking speeds. [ABSTRACT FROM AUTHOR]

Evidence indicates that activation of the parasympathetic nervous system (PNS) suppresses physiological responses associated with motion sickness. Research also shows paced breathing increases PNS activation; the current study examines the use of paced diaphragmatic breathing (DB) training to quell motion sickness symptoms. Healthy participants (N = 60) were pre-screened for motion sickness susceptibility. Participants were then randomly assigned to either a control condition, focusing on environmental awareness, or to an experimental condition implementing paced DB. Following this, participants were exposed to a virtual reality (VR) motion sickness experience, while heart rate variability, breathing rate (RPM), and motion sickness ratings were collected. Results demonstrated participants in the DB condition had higher PNS activation and reported fewer motion sickness symptoms during the VR experience than the participants in the control condition. Results suggest that the DB protocol can be used to significantly increase PNS tone and decrease the development of motion sickness symptoms. [ABSTRACT FROM AUTHOR]

We propose and demonstrate the feasibility of using a highly sensitive microbend multimode fiber optic sensor for simultaneous measurement of breathing rate (BR) and heart rate (HR). The sensing system consists of a transceiver, microbend multimode fiber, and a computer. The transceiver is comprised of an optical transmitter, an optical receiver, and circuits for data communication with the computer via Bluetooth. Comparative experiments conducted between the sensor and predicate commercial physiologic devices showed an accuracy of ±2 bpm for both BR and HR measurement. Our preliminary study of simultaneous measurement of BR and HR in a clinical trial conducted on 11 healthy subjects during magnetic resonance imaging (MRI) also showed very good agreement with measurements obtained from conventional MR-compatible devices. [ABSTRACT FROM AUTHOR]

Correlations between behavioural traits constrain animals to a limited range of behavioural choices and set a limit to the available variation in behavioural phenotype of a population. These constraints are especially important during stressful situations, potentially limiting the ability to cope with stress appropriately. As yet, very little consideration has been given to a possible role for sexual selection in maintaining differences in behavioural stability within individuals: sex-specific differences in behavioural correlations have been seldom studied, especially in the wild. In this field study, we investigated associations between neophobia (latency to enter nest in the presence of a novel object), nest defence (response to a model predator) and breathing rate in response to handling in breeding pied flycatchers ( Ficedula hypoleuca). We did not find any significant difference in antipredator responses between males and females, which indicates low sexual conflict over parental care in the pied flycatcher. However, females were more neophobic than males, while males and females did not differ in their breathing rates. Further, our study demonstrated a strong positive correlation between nest defence behaviour and neophobia in male, but not in female pied flycatchers. Males that defended their nest more had lower breathing rate and higher latency to resume nestling feeding after encountering a predator decoy than males that mobbed less intensely. We found only weak evidence that nest partners might affect each other's behaviour in these contexts. [ABSTRACT FROM AUTHOR]

Background Extracting cardiorespiratory signals from non-invasive and non-contacting sensor arrangements, i.e. magnetic induction sensors, is a challenging task. The respiratory and cardiac signals are mixed on top of a large and time-varying offset and are likely to be disturbed by measurement noise. Basic filtering techniques fail to extract relevant information for monitoring purposes. Methods We present a real-time filtering system based on an adaptive Kalman filter approach that separates signal offsets, respiratory and heart signals from three different sensor channels. It continuously estimates respiration and heart rates, which are fed back into the system model to enhance performance. Sensor and system noise covariance matrices are automatically adapted to the aimed application, thus improving the signal separation capabilities. We apply the filtering to two different subjects with different heart rates and sensor properties and compare the results to the non-adaptive version of the same Kalman filter. Also, the performance, depending on the initialization of the filters, is analyzed using three different configurations ranging from best to worst case. Results Extracted data are compared with reference heart rates derived from a standard pulsephotoplethysmographic sensor and respiration rates from a flowmeter. In the worst case for one of the subjects the adaptive filter obtains mean errors (standard deviations) of -0.2 min-1 (0.3 min-1) and -0.7 bpm (1.7 bpm) (compared to -0.2 min-1 (0.4 min-1) and 42.0 bpm (6.1 bpm) for the nonadaptive filter) for respiration and heart rate, respectively. In bad conditions the heart rate is only correctly measurable when the Kalman matrices are adapted to the target sensor signals. Also, the reduced mean error between the extracted offset and the raw sensor signal shows that adapting the Kalman filter continuously improves the ability to separate the desired signals from the raw sensor data. The average total computational time needed for the Kalman filters is under 25% of the total signal length rendering it possible to perform the filtering in real-time. Conclusions It is possible to measure in real-time heart and breathing rates using an adaptive Kalman filter approach. Adapting the Kalman filter matrices improves the estimation results and makes the filter universally deployable when measuring cardiorespiratory signals. [ABSTRACT FROM AUTHOR]

Aconitine, well-known for its high cardiotoxicity, causes severe arrhythmias, such as ventricular tachycardia and ventricular fibrillation, by opening membrane sodium channels. Tetrodotoxin, a membrane sodium-channel blocker, is thought to antagonize aconitine activity. Tetrodotoxin is a potent blocker of the skeletal muscle sodium-channel isoform Nav1.4 (IC50 10 nM), but micromolar concentrations of tetrodotoxin are required to inhibit the primary cardiac isoform Nav1.5. This suggests that substantial concentrations of tetrodotoxin are required to alleviate the cardiac toxicity caused by aconitine. To elucidate the interaction between aconitine and tetrodotoxin in the cardiovascular and respiratory systems, mixtures of aconitine and tetrodotoxin were simultaneously administered to mice, and the effects on electrocardiograms, breathing rates, and arterial oxygen saturation were examined. Compared with mice treated with aconitine alone, some mice treated with aconitine-tetrodotoxin mixtures showed lower mortality rates and delayed appearance of arrhythmia. The decreased breathing rates and arterial oxygen saturation observed in mice receiving aconitine alone were alleviated in mice that survived after receiving the aconitine-tetrodotoxin mixture; this result suggests that tetrodotoxin is antagonistic to aconitine. When the tetrodotoxin dose is greater than the dose that can block tetrodotoxin-sensitive sodium channels, which are excessively activated by aconitine, tetrodotoxin toxicity becomes prominent, and the mortality rate increases because of the respiratory effects of tetrodotoxin. In terms of cardiotoxicity, mice receiving the aconitine-tetrodotoxin mixture showed minor and shorter periods of change on electrocardiography. This finding can be explained by the recent discovery of tetrodotoxin-sensitive sodium-channel cardiac isoforms (Nav1.1, 1.2, 1.3, 1.4 and 1.6). [ABSTRACT FROM AUTHOR]

Abstract: Territorial animals breeding in high-density environments are more likely to engage in aggressive competition with conspecifics for resources necessary for reproduction. In many avian species, increased competition among breeding females results in increased testosterone concentrations in egg yolks. Generally, elevated yolk testosterone increases nestling growth, competitive behaviors, and bold behavioral traits. However, few studies provide an environmental context with which to examine the potential adaptive benefits of these phenotypic changes. In this study, tree swallow (Tachycineta bicolor) breeding density was altered to modify levels of social competition and yolk testosterone. We measured nestling growth, competitive ability, and breathing rate in response to a stressor using a partial cross-foster design. Females breeding at high-density experienced more aggressive, competitive interactions and their eggs had higher testosterone concentrations. Nestlings that hatched in high-density environments grew faster and displayed more competitive behaviors and a higher breathing rate response to a stressor regardless of post-hatching density. Our study demonstrates that phenotypic plasticity occurs in response to yolk testosterone variation resulting from different breeding densities. These findings suggest that naturally-induced maternal effects prepare offspring for competitive environments, supporting the idea that maternal effects are adaptive. [Copyright &y& Elsevier]

Coping styles represent alternative response patterns in reaction to a stressor. The coping style model provides a set of predictions about correlations between behavioural and neurophysiological reactions to a stressful situation. According to this model, high levels of activity should be correlated with high levels of aggressiveness at the behavioural level, and to high sympathetic reactivity, low parasympathetic reactivity (higher heart rate levels) and low hypothalamus–pituitary–adrenocortical (HPA) axis reactivity (low production of glucocorticoids in response to a stressor). More recent versions of the model, however, are challenging this view and consider the possibility of independent axes of coping style and stress reactivity. The coping style model has mainly been tested on artificially selected or inbred lines in laboratory settings. Such a situation restricts its generalization to a larger number of species and there is a need for studies testing it in the wild under more natural situations. Here, we test the predictions of the coping style model in a wild alpine marmot, Marmota marmota, population. We show that several behavioural (i.e. exploration in an open field, impulsivity and docility) and neurophysiological traits (i.e. heart rate, breathing rate and cortisol production) assumed to represent individual differences in coping style were significantly repeatable over 2–3 years. Not all the correlations between traits predicted by the coping style model were found in marmots, which supports the more recent two-axes model. Furthermore, most correlations were observed at the between-individual level, and the within-individual correlations (i.e. phenotypic plasticity) were weaker. Overall, our results support the prediction of the coping style model, but highlight the fact that the association between traits found in artificial conditions may be weaker in a more natural setting. [ABSTRACT FROM AUTHOR]

The study examines the acute toxicity (48 h) of Lannate insecticide to three species of fish fingerling with different osmoregulatory capabilities, i.e., Oreochromis sp. (GET-Excel tilapia), Lates calcarifer (seabass), and Siganus fuscescens (rabbitfish). After 2 weeks acclimatization period in the laboratory, static bioassays were conducted to determine the median lethal concentration (LC50). Three acute toxicity trials were conducted to determine mortality and observations were done at 3, 6, 12, 24, and 48 h. After 48 h, the mean LC50 values were 7.73 ppm for GET-Excel Tilapia, 6.1 I ppm for Lates calcarifer, and 1.47 ppm for Siganus fuscescens. Immediate changes in breathing rate were also observed upon introduction of Lannate into the medium, with Siganus fuscescens having the highest average breathing rate (74/min). Mortality increased with Lannate concentrations with Siganus fuscescens determined to be most sensitive to Lannate among the three species.Recent use of Lannate insecticide in killing nearshore fishes and the result of this study should serve as a wake-up call to regulate usage of this insecticide at the barangay level, i.e., the smallest administrative unit in the Philippines. [ABSTRACT FROM AUTHOR]

Abstract: The study compares the physiological and behavioural responses to diurnal heat of South African indigenous Windsnyer (WS) pigs and imported Large White (LW) pigs in the hot-wet season in South Africa. Rectal temperature, skin surface temperature, breathing rates and heart rate were each recorded three times per day every other day (0800 h, 1200 h, 1600 h) for a period of 105 days in 12 six-week old gilts of each breed. A completely randomised design was used. There were no differences (P > 0.05) in breathing rate and rectal temperature between the pig breeds. Skin surface temperatures and heart rate were higher (P < 0.05) for the LW pigs than WS pigs at all times of the day. Time of the day affected (P < 0.05) all physiological parameters which generally increased to a peak during mid-day before decreasing at 1600 h. The frequency and duration of wallowing, sprawling in slurry and lying in prostrate posture were higher in LW than WS pigs. Indigenous WS pigs had higher (P < 0.05) values for hair length, final hair density and fat thickness than the LW pigs. These findings suggest that WS pigs could be better at thermoregulation than LW pigs. [Copyright &y& Elsevier]

We show that a mobile phone can serve as an accurate monitor for several physiological variables, based on its ability to record and analyze the varying color signals of a fingertip placed in contact with its optical sensor. We confirm the accuracy of measurements of breathing rate, cardiac R-R intervals, and blood oxygen saturation, by comparisons to standard methods for making such measurements (respiration belts, ECGs, and pulse-oximeters, respectively). Measurement of respiratory rate uses a previously reported algorithm developed for use with a pulse-oximeter, based on amplitude and frequency modulation sequences within the light signal. We note that this technology can also be used with recently developed algorithms for detection of atrial fibrillation or blood loss. [ABSTRACT FROM PUBLISHER]

Although increasing attention is given to both the causes and consequences of variation in animal personality, the measurement of personality in captive or free-ranging individuals remains an issue. In particular, one important question concerns whether personality should be established from the existence of complex behavioral syndromes (a suite of correlated behavioral traits) or could be more easily deduced from a single variable. In that Context, it has recently been suggested that handling stress, measured through breathing rate during handling, could be a good descriptor of personality, at least in passerine birds. The authors experimentally investigated to what extent handling stress was correlated with personality in female zebra finches (Tueniopygia guttata), as assessed from a suite of repeatable behavioral traits, including activity, exploratory behavior, neophobia, and reaction to startle. Although breathing rate was repeatable across individuals, it was not related to any behavioral trait, suggesting that it cannot be used to quickly predict personality, at least in zebra finches. Breathing rate during handling, in addition, was related to morphology, questioning the fact that breathing rate during handling reflects personality irrespective of individual state. The authors suggest that inference on global personality from a reduced number of traits should be performed with caution. [ABSTRACT FROM AUTHOR]

Abstract: Background: Heart and breathing rates are predictors of disease severity and of a poor outcome. However, few reports have compared their machine measurements with traditional manual methods. Setting: A small rural Irish hospital. Methods: The heart and breathing rates of 377 acutely ill medical patients (mean age 68.3 SD 16.8 years) recorded by nursing staff at the time of admission to hospital was compared with those measured over 5min by a piezoelectric belt and ECG monitor (the BT16 acquisition system). Results: The mean breathing rate measured by the nursing staff (20.9 SD 4.8 breaths per min) and that measured by the BT16 piezoelectric belt (19.9 SD 4.5 breaths per min) were significantly different (p 0.004), as were the nurse and BT16 measured heart rates (85.4 SD 21.3 vs. 81.2 SD 18.7, p 0.004), and the correlation coefficient between the two methods of breathing and heart rate measurement were low. Nurse measured breathing rate measurements were clustered around rates of 18, 20 and 22 breaths per min. Unlike those obtained by nurses, BT16 measured heart and breathing rates were shown by logistic regression to be independent predictors of in-hospital mortality. Conclusion: There is a poor correlation between breathing and heart rates measured by traditional methods and those obtained by the BT16 device. BT16 derived breathing and heart rates, but not those measured manually, were independent predictors of in-hospital mortality. [Copyright &y& Elsevier]

Purpose: To determine the dose dependence and kinetics of pneumopathy after systemic administration of rhenium-188 (188Re)-labeled microspheres in a rat model. Methods and Materials: 188Re-microspheres were injected intravenously into adult Wistar rats (n = 54, age, 8 ± 2 months). The rats were divided into 6 groups according to the intended absorbed dose in the lung (maximum 60 Gy). Gamma camera scans were used to estimate the individual whole lung doses. One control group (n = 5) received nonlabeled microspheres. The breathing rate was measured before and weekly after the treatment using whole body plethysmography until 24 weeks. An increase in the breathing rate by 20% compared with the individual pretreatment control value was defined as the quantal endpoint for dose–effect analyses. Results: A biphasic increase in the breathing rate was observed. The first impairment of lung function occurred in Weeks 3–6. For late changes, the interval to onset was clearly dose dependent and was 17 weeks (10–30 Gy) and 10 weeks (50–60 Gy), respectively. The incidence of the response was highly dependent on the estimated lung dose. The median effective dose for an early and late response was virtually identical (19.9 ± 0.6 Gy and 20.4 ± 3.1 Gy, respectively). A significant correlation was found between the occurrence of an early and a late effect in the same rat, suggesting a strong consequential component. Conclusions: The effects of radiolabeled microspheres can be studied longitudinally in a rat model, using changes in the breathing rate as the functional, clinically relevant response. The isoeffective doses from the present study using radionuclide administration and those from published investigations of homogeneous external beam radiotherapy are almost similar. [ABSTRACT FROM AUTHOR]

Arousal from sleep is associated with transient and abrupt cardiorespiratory changes, and elevated arousals associated with sleep disorders may trigger adverse cardiovascular sequela. In this paper, we provide the first data in children on cardiorespiratory responses to cortical arousal. Heart rate and ventilatory responses to arousal from stage 2 and rapid eye movement (REM) sleep were investigated in 40 normal, healthy Caucasian children (age: 7.7 ± 2.6 years; body mass index z-score: 0.30 ± 0.8). All children underwent overnight polysomnography studies. Cortical arousals were scored according to standard criteria. Heart rate changes were assessed over 30 s, starting 15 s prior to cortical arousal onset. Breathing rates were quantified three breaths before and after arousal onset. Arousals from stage 2 as well as REM sleep resulted in an R–R interval shortening of about 15%, independent of age and gender. The R–R interval shortening initiated at least 3 s before the cortical arousal onset. The breathing interval immediately after cortical arousal onset was significantly shortened ( P < 0.001). In conclusion, cortical arousals in children are associated with an increase in breathing rate and significant heart rate accelerations, which typically precede the cortical arousal onset. [ABSTRACT FROM AUTHOR]

Abstract: Previous studies have observed reduced vagal modulation in patients with acute schizophrenia and their first-degree relatives, thus suggesting a genetic predisposition. To investigate vagal modulation, we analyzed the coupling between heart rate and breathing as a putative measure of central autonomic function in 19 patients, 19 of their relatives and 19 matched control subjects. The interaction of heart rate and breathing was investigated in all groups applying the non-linear parameter cross-ApEn, indicating the asynchrony between both time series. In addition, measures of the time and frequency domain of heart rate variability (HRV) were obtained. The main finding of our study is a significantly increased cross-ApEn value, indicating reduced central vagal modulation both in relatives and patients suffering from schizophrenia. Non-linear measures of HRV proved to more sensitively differentiate relatives from control subjects. Furthermore, we observed a correlation between psychopathology and breathing, indicating that positive symptoms are associated with a higher degree of regularity in the breathing pattern. Our results suggest that autonomic dysfunction previously described for patients suffering from schizophrenia is also present in first-degree relatives. This might relate to changes of brainstem activity in patients and relatives, and a common genetic background in patients and their family members can be assumed. [Copyright &y& Elsevier]

Abstract: Altered amygdala activity in patients with schizophrenia can influence respiratory patterns and consequently cardiovascular parameters. Hence, we examined respiration and heart rate time series complexity as well as coupling of both signals. Electrocardiograms and respiratory signals were obtained from 25 unmedicated patients with schizophrenia and controls. Approximate entropy (ApEn) was calculated for heart and respiratory rates as well as cross-ApEn reflecting coupling of both signals. Coupling was decreased indicating diminished vagal modulation at the brain stem level. Regularity of breathing correlated with disease severity. These data might reflect a lack of inhibitory control over brainstem centers in schizophrenia. [Copyright &y& Elsevier]

This study investigated the effect of psychological pressure on physiological responses during the golf putting stroke. Six young adults (four males and two females) participated in the study. The experiment was comprised of a contest that consisted of four sessions, with a dinner prize awarded to the winner. In each session, the subject was instructed to attempt 20, 9-foot putts. Eye, head, and putter motions, as well as heart rate and breathing rate, were objectively recorded during each trial. For all sessions, each successful putt was awarded a score of +2 points. However, as the four sessions progressed, any missed putt was given progressively greater negative scores: -2, -3, -4, and -5 points, respectively. At the end of the experiment, the subject rated the perceived pressure during each session on a scale of 1 to 5, with 1 corresponding to no pressure and 5 corresponding to extreme pressure. Overall, the results demonstrated that the apparently simple act of putting involves a complex interplay among various physiological and neurological control parameters, hence reflecting a myriad of emotions that are magnified under increased psychological pressure. [ABSTRACT FROM AUTHOR]

The whole lung of rats was irradiated with X-rays, thermal neutrons, or thermal neutrons in the presence of p-boronophenylalanine (BPA). A ⩾20% increase in breathing rate, in the period 40–80 days after irradiation, was indicative of radiation-induced pneumonitis. The ED50 (±SE) for a ⩾20% increase in breathing rate, relative to age-matched controls, was 11.6±0.13 Gy for X-rays and 9.6±0.08 Gy for neutrons only. This indicated a thermal neutron beam RBE of 1.2 and an RBE of 2.2 for the high-LET components of the dose, assuming a dose reduction factor of 1.0 for gamma rays. Preliminary data indicate the compound biological effectiveness factor for BPA in the lung is approximately 1.5. [Copyright &y& Elsevier]

This paper deals with the assumption that young adults with self-reported multiple chemical sensitivity (sMCS) show a heightened sensitivity of autonomic functions during experimental solvent exposure. Male sMCS-subjects were selected (out of n=274) on the base of a German questionnaire on chemical and environmental sensitivity (CGES). Two independent experiments were carried out, each with 12 sMCS-subjects and 12 age-matched control-subjects. In experiment I two concentrations of the solvents ethyl benzene (10 and 98 ppm) and 2-butanone (10 and 189 ppm) were used. Experiment II investigated 2-propanol (35 and 190 ppm) and 1-octanol (0.1 and 6.4 ppm). The low concentrations correspond nearly to the olfactory thresholds while the high concentrations correspond to the German occupational threshold limit values (MAC). The exposure duration under each condition was 4 h. The sequence of the four exposure conditions was random including intervals of at least 2 days without exposure. During the exposure physiological changes of breathing rate and heart rate were recorded. Two 30 min intervals with a sedentary position of the subjects at the beginning and end of exposure were chosen for analyses. Neither in experiment I nor in experiment II significant specific reactions to the type or level of the exposures were found. The autonomic functions in both experiments revealed alterations within the exposure sessions. The heart rate in experiment II and the breathing rate in both experiments decreased significantly during the analyzed 30 min intervals. Furthermore, in both experiments the heart rates decreased significantly from beginning to end of exposure. Only in experiment I the mean breathing rate of sMCS-subjects was generally higher compared to the control-subjects. Regarding the assumption of a heightened sensitivity of sMCS-subjects the two experiments yielded controversial results. Thus, the hypothesis of stronger responses of autonomic functions of sMCS-subjects provoked by various exposure scenarios remains open. [Copyright &y& Elsevier]