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Altered breathing rate is an important sign of disease status. Currently used machine-based monitoring of the breathing rate includes contact with the body, which may result in pain and discomfort. In this paper, a non-contact breathing monitoring technique is proposed by integrating RGB and thermal imaging systems with RGB-thermal image registration. This method provides a linear mapping for automated selection of the region of interest (ROI) followed by tracking to extract the breathing rate. To evaluate the efficacy of the proposed approach and its robustness against motion, talking, varying breathing rate or rhythm, and high ambient temperature, this study was conducted in three phases. Validation of the proposed approach demonstrated a strong agreement with the reference method of breathing rate monitoring using a respiration belt. During normal breathing, the mean absolute error (MAE) reached 0.11 bpm (breaths per minute). While in more challenging conditions, defined by three phases, the MAE reached 1.46, 2.08, and 1.69 bpm, respectively. In short, the proposed method performance is a promising alternative to a contact-based method due to its strong agreement and might be useful in diverse applications such as sport studies, rehabilitation centres, quarantine centres, and in hospital or airport screening during the COVID 19 pandemic. [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]

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]

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]

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]

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]

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]

Impedance pneumography (ImP) is widely used for respiratory rate (RR) monitoring. However, ImP-derived RRs can be imprecise. The aim of this study was to develop a signal quality index (SQI) for the ImP signal, and couple it with a RR algorithm, to improve RR monitoring. An SQI was designed which identifies candidate breaths and assesses signal quality using: the variation in detected breath durations, how well peaks and troughs are defined, and the similarity of breath morphologies. The SQI categorises 32 s signal segments as either high or low quality. Its performance was evaluated using two critical care datasets. RRs were estimated from high-quality segments using a RR algorithm, and compared with reference RRs derived from manual annotations. The SQI had a sensitivity of 77.7 %, and specificity of 82.3 %. RRs estimated from segments classified as high quality were accurate and precise, with mean absolute errors of 0.21 and 0.40 breaths per minute (bpm) on the two datasets. Clinical monitor RRs were significantly less precise. The SQI classified 34.9 % of real-world data as high quality. In conclusion, the proposed SQI accurately identifies high-quality segments, and RRs estimated from those segments are precise enough for clinical decision making. This SQI may improve RR monitoring in critical care. Further work should assess it with wearable sensor data. [ABSTRACT FROM AUTHOR]