Respiratory Amplitude Research Articles

The Functional Neurometry of Nelson Alves Pereira Júnior: An Advanced Method of Mapping and Biofeedback Training of the Autonomic Nervous System Functions

Introduction: Functional Neurometry makes Biofeedback tools already demonstrated in the literature, such as: galvanic skin response, cardiac coherence and variability, thermoregulatory and respiratory interact with each other. Objective: The aim of this study was to report the historical and methodological aspects of the Functional Neurometry protocols. Method: A review was made in the MEDLINE / PubMed electronic indexing database and in the Web of Science. Results: This method intends to synchronize the frequencies of various organs linked to the autonomic nervous system (ANS) to control anxiety. Assessment and training are organized into categories. The categories of the assessment protocol are: 1st) Anxiety Control; 2nd) Physiological Response; 3rd) Baroreflex Index; 4th) hemodynamics; and 5th) Brain Neurometry and the training protocol categories are: I) Sound Anxiety Control; II) Visual Anxiety Control; III) Emotional Variability; IV) Respiratory Amplitude and Frequency; V) Progressive Muscle Relaxation; VI) Functional Physiological Response; VII) Respiratory Functional Capacity; VIII) Heart Rate Variability and IV) Cardiac Coherence. Conclusion: Functional neurometry mainly allows the balance of the ANS, making it a protective filter of the central nervous system.

Feasibility of Non-contrast-enhanced Coronary Magnetic Resonance Angiography at 3.0T

Objective To evaluate the feasibility of non-contrast-enhanced magnetic resonance angiography (NCE-MRA) on a 3.0T scanner. Methods Totally 36 volunteers and 24 patients with clinically suspected coronary artery disease underwent NCE-MRA. The quality of the NCE-MRA images was graded for each segment on a four-point scale. The subjects were divided into two groups according to image quality. The age,body mass index (BMI),heart rate,end-expiratory diaphragm displacement,and respiratory diaphragm motion amplitude were evaluated and compared. Results The average image quality score of every segment was above 2 points. The proximal and middle segments of left anterior descending artery had significantly higher quality scores than the distal segments (P=0.000) and the proximal segment of left circumflex coronary artery had significantly higher quality scores than the distal segments (P=0.000),the proximal segment of right coronary artery also had a significant higher quality score than its distal segment (P=0.001). The image quality was good in 38 subjects (64.4%). The heart rate [(66.35±9.39) beat/min vs. (75.32±11.67) beat/min] (P=0.002) and the body mass index [(24.72±3.33) kg/m 2 vs. (27.82±3.61) kg/m 2] (P=0.002) were significantly different between the good image quality group and the poor image quality group. The end-expiratory diaphragm displacement in good image quality group was (4.43±2.07)mm,which was significantly lower than that in poor image quality group [(9.26±7.62)mm](P=0.013). The respiratory diaphragm motion amplitude [(21.35±6.02) mm] in good image quality group was significantly lower than that in poor image quality group [(30.68±14.20)mm](P=0.012). Conclusion NCE-MRA on 3.0T is a feasible tool for visualization of the proximal and middle segments of coronary arteries,and the image quality can be optimized by controlling heart rate and respiration in the future.

Autonomic laterality in caloric vestibular stimulation

BACKGROUNDCaloric stimulation of the vestibular system is associated with autonomic response. The lateralization in the nervous system activities also involves the autonomic nervous system.AIMTo compare the effect of the right and left ear caloric test on the cardiac sympathovagal tone in healthy persons.METHODSThis self-control study was conducted on 12 healthy male volunteers. The minimal ice water caloric test was applied for vestibular stimulation. This was done by irrigating 1 milliliter of 4 ± 2 °C ice water into the external ear canal in 1 s. In each experiment, only one ear was stimulated. For each ear, the pessimum position was considered as sham control and the optimum position was set as caloric vestibular stimulation of horizontal semicircular channel. The order of right or left caloric vestibular stimulation and the sequence of optimum or pessimum head position in each set were random. The recovery time between each calorie test was 5 min. The short-term heart rate variability (HRV) was used for cardiac sympathovagal tone metrics. All variables were compared using the analysis of variance.RESULTSAfter caloric vestibular stimulation, the short-term time-domain and frequency-domain HRV indices as well as, the systolic and the diastolic arterial blood pressure, the respiratory rate and the respiratory amplitude, had no significant changes. These negative results were similar in the right and the left sides. Nystagmus duration of left caloric vestibular stimulations in the optimum and the pessimum positions had significant differences (e.g., 72.14 ± 39.06 vs 45.35 ± 35.65, P < 0.01). Nystagmus duration of right caloric vestibular stimulations in the optimum and the pessimum positions had also significant differences (e.g., 86.42 ± 67.20 vs 50.71 ± 29.73, P < 0.01). The time of the start of the nystagmus following caloric vestibular stimulation had no differences in both sides and both positions.CONCLUSIONMinimal ice water caloric stimulation of the right and left vestibular system did not affect the cardiac sympathovagal balance according to HRV indices.

Emotion Recognition Based on Multiple Physiological Signals

Emotion is a series of reactions triggered by a specific object or situation that affects a person's physiological state and can, therefore, be identified by physiological signals. This paper proposes an emotion recognition model. Extracted the features of physiological signals such as photoplethysmography, galvanic skin response, respiration amplitude, and skin temperature. The SVM-RFE-CBR(Recursive Feature Elimination-Correlation Bias Reduction-Support Vector Machine) algorithm was performed to select features and support vector machines for classification. Finally, the model was implemented on the DEAP dataset for an emotion recognition experiment. In the rating scale of valence, arousal, and dominance, the accuracy rates of 73.5%, 81.3%, and 76.1% were obtained respectively. The result shows that emotional recognition can be effectively performed by combining a variety of physiological signals.

Modified FMCW system for non-contact sensing of human respiration

Small displacement detection capability becomes an important key for developing non-contact sensor for human respiration based on radar system. Frequency modulated continuous wave (FMCW) radar has been widely studied and applied for many applications. With respect to the conventional perspective, large bandwidth is needed for detecting the small displacement related to the human respiration. Meanwhile, extracting the respiration pattern from Doppler response has a drawback in identifying the small displacement location. In this paper, the modification on FMCW system was proposed for obtaining the capability in detecting the human respiration and its distance from the radar. Detecting the phase value of the low pass filter (LPF), output from conventional FMCW was investigated and applied as a modification concept. The pattern, rate and amplitude of respiration are extracted from phase detector output. Beat frequency detection is still elaborated for synthesising the reference signal for phase detection. The result shows that the modified FMCW system proposed the capability of detecting the rate and amplitude respiration and location of the target.

Long-Term Physical Exercise and Mindfulness Practice in an Aging Population.

Previous studies have shown that physical exercise and mindfulness meditation can both lead to improvement in physical and mental health. However, it is unclear whether these two forms of training share the same underlying mechanisms. We compared two groups of older adults with 10 years of mindfulness meditation (integrative body-mind training, IBMT) or physical exercise (PE) experience to demonstrate their effects on brain, physiology and behavior. Healthy older adults were randomly selected from a large community health project and the groups were compared on measures of quality of life, autonomic activity (heart rate, heart rate variability, skin conductance response, respiratory amplitude/rate), immune function (secretory Immunoglobulin A, sIgA), stress hormone (cortisol) and brain imaging (resting state functional connectivity, structural differences). In comparison with PE, we found significantly higher ratings for the IBMT group on dimensions of life quality. Parasympathetic activity indexed by skin conductance response and high-frequency heart rate variability also showed more favorable outcomes in the IBMT group. However, the PE group showed lower basal heart rate and greater chest respiratory amplitude. Basal sIgA level was significantly higher and cortisol concentration was lower in the IBMT group. Lastly, the IBMT group had stronger brain connectivity between the dorsal anterior cingulate cortex (dACC) and the striatum at resting state, as well as greater volume of gray matter in the striatum. Our results indicate that mindfulness meditation and physical exercise function in part by different mechanisms, with PE increasing physical fitness and IBMT inducing plasticity in the central nervous systems. These findings suggest combining physical and mental training may achieve better health and quality of life results for an aging population.

Lactate stimulates central respiratory motor output in bullfrogs, Lithobates catesbeianus

Ventilation must constantly change to meet varying metabolic and acid‐base regulation needs of the organism. Although O2 and CO2/pH sensors have received much attention for the chemical control of breathing, metabolites such as lactate and ATP have recently been shown to play important roles in both the hypoxic and hypercapnic ventilatory responses of vertebrates. In mammals and fish, lactate anions increase ventilation through peripheral mechanisms, but the actions of lactate in the central respiratory network of any vertebrate species remain unclear. Anuran amphibians (frogs and toads) accumulate large amounts of lactate in the brain during periods of high respiratory drive, suggesting that lactate may act at central sites to stimulate breathing. For example, hypoxia increases brain lactate which may contribute to elevated ventilation following physiological hypoxia caused by breath‐holding. Furthermore, anurans perform mainly anaerobic exercise, leading to large lactate loads in the blood that may get delivered to the brain through transporters present in the blood‐brain barrier. Thus, we tested the hypothesis that lactate stimulates output from the central respiratory network in amphibians. To test this hypothesis, we measured respiratory‐related cranial nerve X (CNX) and hypoglossal nerve (SNII) activity in isolated brainstem‐spinal cord preparations from the American bullfrog, Lithobates catesbeianus, in response to sodium lactate (lac−; n=8). The brainstem‐spinal cord preparation is advantageous because we can assess the actions of lac− on rhythm generating and motor functions of the respiratory network independent of peripheral feedback. Lac− failed to increase frequency of the respiratory rhythm and amplitude of CNX output. However, we identified a striking dose‐dependent increase in amplitude of respiratory‐related SNII output in each preparation, indicating enhanced motor neuron firing and/or recruitment by lac− (P=0.008; Friedman test; 0.5 mM= 33±11, 2 mM= 56±19, 4 mM= 89±29 % increase above baseline). To control for slight increases in [Na+], osmolality, extracellular pH, and time during exposure to sodium lactate, we superfused a separate group of preparations with 0.5, 2, and 4 mM sodium bicarbonate (HCO3−; n=4). HCO3− did not increase the motor amplitude of either SNII or CNX (P&gt;0.9; Friedman test). Thus, lactate anions lead to increased respiratory motor output of SNII, which may enhance activation of buccal floor musculature during periods of high respiratory demand such as hypoxia and exercise. Overall, this work directly implicates lactate anions in the control of central motor networks that regulate breathing in vertebrates.Support or Funding InformationThis work was funded by start‐up funds provided by UNC‐Greensboro to JS.

Caffeine Abolishes TrkB Receptor‐Dependent Respiratory‐Related Spinal Motor Facilitation in Isolated Neonatal Rat Brainstem‐Spinal Cords In Vitro

Caffeine is the main treatment for apnea of prematurity because it stimulates breathing, reduces duration of respiratory support, and increases infant survival. Caffeine has multiple neuronal effects, but it is a well‐established adenosine A2a receptor (A2aR) antagonist. In adult rats, A2aR blockade increases the magnitude of intermittent hypoxia‐induced, TrkB receptor‐dependent, long‐term facilitation of phrenic motor output. In neonates, it is not known whether caffeine blocks A2aRs and enhances TrkB receptor‐induced facilitation of respiratory motor output. To test this question, neonatal (P0‐P3) rat brainstem‐spinal cords were isolated and respiratory‐related motor output recorded from C4‐C5 ventral spinal roots. Bath‐applied dihydroxyflavone (DHF, TrkB receptor agonist, 5–10 μM, 9‐min, n=22) increased respiratory motor burst amplitude by 13 ± 3% relative to baseline at 75 min following drug application, whereas vehicle dimethylsulfoxide‐treated time controls decreased burst amplitude by 11 ± 4% relative to baseline (n=15; p&lt;0.001). A background caffeine application (50–250 μM; 15 min) that overlapped a DHF application (5–10 μM, 9 min) abolished DHF‐induced spinal motor facilitation (burst amplitude was decreased by 7 ± 4% relative to baseline at 75 min). The lack of DHF‐induced spinal motor facilitation with caffeine pretreatment could be due to decreased endogenous signaling in neonatal rat A2aRs (i.e., little or no crosstalk inhibition), or other caffeine effects, such as phosphodiesterase inhibition. If TrkB‐dependent spinal motor facilitation is beneficial in neonates, then caffeine administration may compromise one compensatory mechanism during apnea of prematurity.Support or Funding InformationSupported by: NS085226 (JJW), HL105511 (TLB)

Cotinine enhances the nicotine‐mediated decrease in respiratory burst amplitude recorded from the hypoglossal nerve in the brainstem spinal cord preparation from nicotine‐exposed neonatal rats

Cotinine, the primary metabolite of nicotine, can be detected in the blood of infants born to mothers who used nicotine products during pregnancy and breast feeding, and is used as a marker of nicotine exposure. Previous research shows that prenatal nicotine exposure alters the regions of the brain that control breathing and results in impaired protective breathing reflexes in exposed human and animal neonates. These abnormalities are proposed as a mechanism to explain Sudden Infant Death Syndrome (SIDS), and maternal smoking is the number one risk factor for SIDS. While it has long been known that nicotine has direct effects on brain function and development, it has only recently been established that cotinine may act on the brain as well. Both nicotine and cotinine bind to nicotinic acetylcholine receptors (nAChRs) which are expressed on neurons throughout the nervous system. Preliminary data using the in vitro brainstem spinal‐cord preparation from nicotine‐exposed neonatal rats shows that activation of nAChRs produces a decrease in the amplitude of respiratory bursts recorded from hypoglossal nerve roots (−30.74±18.2 % baseline, n=4), and that this effect is enhanced by cotinine (−60.34±16.1 % baseline, n=4). This supports the hypothesis that cotinine modulates the function of nAChRs in regions of the brain that control breathing (P&lt;0.0001).Support or Funding Information5R01HD071302‐07

Comparison of clinical outcomes between passive scattering versus pencil-beam scanning proton beam therapy for hepatocellular carcinoma

Background and purposeOur study aimed to compare the oncologic outcomes and toxicities between passive scattering (PS) proton beam therapy (PBT) and pencil-beam scanning (PBS) PBT for primary hepatocellular carcinoma (HCC). Materials and methodsThe multidisciplinary team for liver cancer identified the PBT candidates who were ineligible for resection or radiofrequency ablation. We retrospectively analyzed 172 patients who received PBT for primary HCC from January 2016 to December 2017. The PS with wobbling method was applied with both breath-hold and regular breathing techniques, while the PBS method was utilized only for regular breathing techniques covering the full amplitude of respiration. To maintain the balance of the variables between the PS and PBS groups, we performed propensity score matching. ResultsThe median follow-up duration for the total cohort was 14 months (range, 1–31 months). After propensity score matching, a total of 103 patients (70 in the PS group and 33 in the PBS group) were included in analysis. There were no significant differences in the rates of overall survival (OS), in-field local control (IFLC), out-field intrahepatic control (OFIHC), extrahepatic progression-free survival (EHPFS), and complete response (CR) between the matched groups. In the subgroup analyses, no subgroup showed a significant difference in IFLC between the PS and PBS groups. There was also no significant difference in the toxicity profiles between the groups. ConclusionThere are no differences in oncologic outcomes, including OS, IFLC, OFIHC, EHPFS, and CR rates, or in the toxicity profiles between PS and PBS PBT for primary HCC.

Delta plot analysis of cardiovascular and cardiorespiratory interactions in young women with orthostatic intolerance

ObjectiveTemporal dynamics of cardiovascular and cardiorespiratory interactions during a head-up tilt test (HUTT) were investigated using a new method called delta plot analysis (DPA) that deals with the intrinsic nonstationarity feature of time series. MethodsTwenty-one young female patients (28 ± 7 years) with orthostatic intolerance (OI) and 13 age-matched female controls (26 ± 5 years) were investigated during a 70° HUTT. Analyses were performed on bivariate time series including beat-to-beat intervals (BBI), respiratory amplitude (RESP) at BBI onset as well as systolic (SYS) and diastolic (DIA) blood pressure at simultaneous and shifted beats. DPA was used to characterize cardiovascular interactions as SYS→BBI and BBI→DIA, as well as cardiorespiratory interactions as RESP→BBI and RESP→DIA. ResultsOccurrence of simultaneous BBI increases due to SYS increases (bradycardic baroreflex) was significantly reduced during orthostatic phase in patients (28.54 ± 6.32% versus 36.35 ± 4.77%, p < 0.01). Considering the magnitude of consecutive changes, patients revealed an increased amount of points characterized by low heart rate variability combined with high blood pressure variability for SYS→BBI at tau = 0, BBI→SYS at tau = 2 and BBI→DIA at tau = 1. Interaction analysis for SYS→BBI showed highly significant differences already in supine position (10.08±5.90% versus 4.78±2.42%, p < 0.01), during tilt-up (12.32±5.00% versus 5.51±3.07%, p < 0.0001) and during early orthostatic phase (14.55±6.00% versus 5.71±3.14%, p < 0.001). ConclusionTemporal dynamic analysis by DPA revealed impaired autonomic control in patients compared to healthy subjects during supine position, transition and orthostatic phase. SignificanceDPA is a promising graphical tool to demonstrate impaired autonomic regulation.

Clinical evaluation of stretchable and wearable inkjet-printed strain gauge sensor for respiratory rate monitoring at different measurements locations

The respiration rate (RR) is a vital sign in physiological measurement and clinical diagnosis. RR can be measured using stretchable and wearable strain gauge sensors which detect the respiratory movements in the abdomen or thorax areas caused by volumetric changes. In different body locations, the accuracy of RR detection might differ due to different respiratory movement amplitudes. Few studies have quantitatively investigated the effect of the measurement location on the accuracy of new sensors in RR detection. Using a stretchable and wearable inkjet-printed strain gauge (IPSG) sensor, RR was measured from five body locations (umbilicus, upper abdomen, xiphoid process, upper thorax, and diagonal) on 30 healthy test subjects while sitting on an armless chair. At each location, reference RR was simultaneously detected by the e-Health sensor, and the measurement was repeated twice. Subjects were asked about the comfortableness of locations. Based on Levene's test, ANOVA was performed to investigate if there is a significant difference in RR between sensors, measurement locations, and two repeated measurements. Bland-Altman analysis was applied to the RR measurements at different locations. The effects of measurement site and measurement trials on RR difference between sensors were also investigated. There was no significant difference between IPSG and reference sensors, between any locations, and between the two measurements (all p > 0.05). As to the RR deviation between IPSG and reference sensors, there was no significant difference between any locations, or between two measurements (all p > 0.05). All the 30 subjects agreed that diagonal and upper thorax positions were the most uncomfortable and most comfortable locations for measurement, respectively. The IPSG sensor could accurately detect RR at five different locations with good repeatability. Upper thorax was the most comfortable location.

Noninvasive Monitoring of Vital Signs Based on Highly Sensitive Fiber Optic Mattress

A smart mattress based on optical fiber Mach-Zender interferometer (OF-MZI) is designed for noninvasive and continuous monitoring of human vital signs. Through arranging the sensing fiber between two elastic covering layers with sandwich structure, the mattress was sensitive to the respiration and heartbeat induced micro-pressure. In the processing terminal, the waveforms of vital signs were demodulated by 3 <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">*</sub> 3 coupler based differentiate and cross-multiplying method, and then four characteristic indicators including the heart rate, heartbeat amplitude, respiration rate, and respiration amplitude were respectively extracted through feature extraction algorithm, for evaluating the human health condition. Clinical experimental results of eighteen subjects indicate that the mattress system could not only distinguish the activity states of no body, on bed, body movement and off bed, but also contribute to clinical diagnosis of bradycardia, tachycardia, polypnea and apnoea. By adopting Bland-Altman analysis method, good reproducibility and accuracy were confirmed, where the max errors of heart rate and respiration rate are respectively 2 bpm and 1 bpm. Moreover, the responses at different positions of the mattress are identical and the continuous monitoring results in one day are consistent with daily change of vital signs, which proves that the fiber optic mattress has good reliability and stability. Beneficial from high-sensitivity, multiple parameters, long-term continuous monitoring, high comfortability and low cost, the mattress is promising in the early detection and prevention of cardiac and respiratory diseases as a household medical device.

Respiration Signal Extraction From Pulse Wave Collected by PVDF Sensor

The respiratory signal is a critical index of cardiopulmonary function. In this paper, we implement the polyvinylidene fluoride (PVDF) sensor to collect the data of pulse waves and reference respiration signals. The correlations between the major feature values and breaths are investigated and presented. As a result, several feature values exhibit relatively good correlations with reference respiratory amplitude. The improvements of Kalman Filter for the respiratory signals extracted from feature value variances are also introduced. Moreover, we display the comparisons with low-pass filtering, Wavelet filtering, and ensemble empirical mode decomposition (EEMD) method. Using the method of identifying error breaths, the error rate of the new method is about 4.146%. The new method is feasible for real-time applications at quiet state.

Distress symptoms development after a single episode of ultrasound exposure

Aim. To study the influence of a single 24-hour episode of exposure to ultrasound waves propagating in air on microcirculation and parameters of hemostasis in rats.&#x0D; Methods. The study was performed on 28 Wistar male rats. The experimental group was exposed to ultrasound for 24 hours. Geometric mean frequency was 25 kHz, acoustic pressure was 84.3 dB. Parameters of microcirculation of experimental rats received by laser Doppler flowmetry were compared with those of intact animals. Also comparative analysis of platelet and coagulation hemostasis, anticoagulant and fibrinolytic plasma activity was performed in rats from both groups.&#x0D; Results. In experimental rats in response to 24-hour exposure to ultrasound, significant decrease of the studied active and passive factors of blood flow modulation occurred compared to those of intact animals: parameters of microcirculation, flax, endothelial and vasomotor wave amplitude, respiratory and pulse wave amplitude. When studying the parameters of hemostasis, significant hypercoagulation of extrinsic pathway and at the latest stages of coagulation which worsened with anticoagulant plasma activity inhibition along with decrease of fibrinolytic activity. The character of changes of hemostatic parameters confirmed the development of stress-reaction in rats registered during the study of microcirculation.&#x0D; Conclusion. 24-hour ultrasound exposure causes significant disorders of microcirculation and unfavorable shifts in hemostasis - the signs of distress.

Characterization of continuous bed motion effects on patient breathing and respiratory motion correction in PET/CT imaging.

Continuous bed motion (CBM) was recently introduced as an alternative to step‐and‐shoot (SS) mode for PET/CT data acquisition. In CBM, the patient is continuously advanced into the scanner at a preset speed, whereas in SS, the patient is imaged in overlapping bed positions. Previous investigations have shown that patients preferred CBM over SS for PET data acquisition. In this study, we investigated the effect of CBM versus SS on patient breathing and respiratory motion correction. One hundred patients referred for PET/CT were scanned using a Siemens mCT scanner. Patient respiratory waveforms were recorded using an Anzai system and analyzed using four methods: Methods 1 and 2 measured the coefficient of variation (COV) of the respiratory cycle duration (RCD) and amplitude (RCA). Method 3 measured the respiratory frequency signal prominence (RSP) and method 4 measured the width of the HDChest optimal gate (OG) window when using a 35% duty cycle. Waveform analysis was performed over the abdominothoracic region which exhibited the greatest respiratory motion and the results were compared between CBM and SS. Respiratory motion correction was assessed by comparing the ratios of SUVmax, SUVpeak, and CNR of focal FDG uptake, as well as Radiologists’ visual assessment of corresponding image quality of motion corrected and uncorrected images for both acquisition modes. The respiratory waveforms analysis showed that the RCD and RCA COV were 3.7% and 33.3% lower for CBM compared to SS, respectively, while the RSP and OG were 30.5% and 2.0% higher, respectively. Image analysis on the other hand showed that SUVmax, SUVpeak, and CNR were 8.5%, 4.5%, and 3.4% higher for SS compared to CBM, respectively, while the Radiologists’ visual comparison showed similar image quality between acquisition modes. However, none of the results showed statistically significant differences between SS and CBM, suggesting that motion correction is not impacted by acquisition mode.

Adrenergic reactions during N3 sleep arousals in sleepwalking and sleep terrors: The chicken or the egg?

To understand the mechanisms of N3 sleep interruptions in patients with sleepwalking episodes and/or sleep terrors (SW/ST), we evaluated whether autonomic reactions preceded or accompanied behavioural arousals from NREM sleep stage N3. In 20 adult patients with SW/ST and 20 matched controls without parasomnia, heart rate and pulse wave amplitude were measured beat-to-beat during the 10 beats preceding and during the 15 beats succeeding a motor arousal from N3 sleep. Respiratory rate and amplitude were measured during the same 25 successive beats. In patients with SW/ST, the N3 arousals were associated with a 33% increase in heart rate, a 57% decrease in pulse wave amplitude (indicating a major vasoconstriction), a 24% increase in respiratory rate and a doubling of respiratory amplitude. Notably, tachycardia and vasoconstriction started 4s before motor arousals. A similar profile (tachycardia and vasoconstriction gradually increasing from the 4s preceding arousal and post-arousal increase of respiratory amplitude, but no polypnea) was also observed, with a lower amplitude, during the less frequent 38 quiet N3 arousals in control subjects. Parasomniac arousals were associated with greater tachycardia, vasoconstriction and polypnea than quiet arousals, with the same pre-arousal gradual increases in heart rate and vasoconstriction. Autonomic arousal occurs 4s before motor arousal from N3 sleep in patients with SW/ST (with a higher adrenergic reaction than in controls), suggesting that an alarming event during sleep (possibly a worrying sleep mentation or a local subcortical arousal) causes the motor arousal.

Use Of Tai Chi Elements To Increase Respiratory Amplitude

High performance sport has a major impact on the physiological adaptations of the respiratory system. The importance of the optimal functioning of this system is essential to achieve top results in high performance sport but also in maintaining a long term health status. Science journals present numerous studies that highlight the benefits of practicing Tai Chi on the general population, with effects ranging from improving cardiac function, to influencing the immune system. The purpose of this study is to identify whether by practicing Tai Chi forms a athlete can change their breathing pattern and develop their respiratory amplitude. The subjects of the study were 22 fencing practitioners, accredited at the Iași Municipal Sports Club (C.S.M. Iași), aged between 14 and 18 years, with over 3 years of competitive activity. Materials and method: The study participants were evaluated initially and at the end of 7 months of practice. The frequency was 3 sessions per week, and the duration of each session was 20-30 minutes. The evaluation consisted in measuring the circumference of the thorax at 3 different levels: subaxillary, medial thorax (T6-T7) and lower rib (diaphragmatic) in maximal inspiration and expiration. Conclusions: A constant evolution is observed in most of the exposed cases. In cases where this evolution is not visible, a change in the breathing mode can be noticed, transforming from an upper rib breathing into a thoracic or abdominal breathing. With the exception of one case, all subjects had an improvement of the value in the lower rib level.

Multisensor data fusion of motion monitoring system based on BP neural network

Recently, many researchers have proposed a number of respiratory monitoring methods to monitor the respiratory amplitude and respiratory rate of athletes under different conditions. However, the problem with such methods is that their accuracy is not high. Therefore, this paper proposes a respiratory monitoring method based on a BP neural network combined with multisensor fusion technology. First, we fix multiple sensors on the chest and back of the human body so that we can accurately measure the acceleration and angular velocity changes caused by the contraction and expansion of the chest contour when athletes breathe under different motion conditions. After a coordinate measurement is performed on the data measured by the back measurement unit, the BP network algorithm is used to obtain the acceleration curve under the simple respiratory motion state. Finally, the respiratory frequency and respiratory depth parameters, which are important indicators for evaluating athletes’ physical fitness, can be obtained for the athletes under different motion states. Verification was carried out in an experimental platform, and the experimental results for different postures of the human body were compared with the standard respiratory mask measurement results. The accuracy rate was over 90%, thus realizing the networking, portability, and wearability of the breathing state sensors, which provide real-time accurate measurements.

Dosimetric impact of respiratory motion during boron neutron capture therapy for lung cancer

Lung cancer is one of the cancers with high morbidity and mortality. Boron neutron capture therapy (BNCT) has attracted researchers’ attention in recent years because of its unique advantages in lung cancer treatment. However, changes in dose distribution in BNCT due to respiratory motion have not been studied. In this work, the tumor dose deviation caused by respiration was quantitatively investigated. Four-dimensional Computed Tomography (4D CT) was used to construct the virtual respiratory patient model in this study. Six phases (e.g., 10%, 20%, 50%, 60%, 80%, and 90%) were selected to represent the anatomy of patients at different moments throughout the respiratory cycle. Tumor-related dose volume histograms (DVH) indices at different phases were calculated using Monte Carlo toolkit. The results showed that the dose difference increased with the increasing of respiratory motion amplitude. In the three movement directions of the tumor, the dose changes caused by the movement in the anterior–posterior (AP) direction were remarkable under the treatment planning configurations we studied. The differences of tumor mean dose ranged from −13.8% to 15.8%. Similar conclusions were observed in the cases of three real patients.