Sample records for active breathing control

  1. Consciously controlled breathing decreases the high-frequency component of heart rate variability by inhibiting cardiac parasympathetic nerve activity. (United States)

    Sasaki, Konosuke; Maruyama, Ryoko


    Heart rate variability (HRV), the beat-to-beat alterations in heart rate, comprises sympathetic and parasympathetic nerve activities of the heart. HRV analysis is used to quantify cardiac autonomic regulation. Since respiration could be a confounding factor in HRV evaluation, some studies recommend consciously controlled breathing to standardize the method. However, it remains unclear whether controlled breathing affects HRV measurement. We compared the effects of controlled breathing on HRV with those of spontaneous breathing. In 20 healthy volunteers, we measured respiratory frequency (f), tidal volume, and blood pressure (BP) and recorded electrocardiograms during spontaneous breathing (14.8 ± 0.7 breaths/min) and controlled breathing at 15 (0.25 Hz) and 6 (0.10 Hz) breaths/min. Compared to spontaneous breathing, controlled breathing at 0.25 Hz showed a higher heart rate and a lower high-frequency (HF) component, an index of parasympathetic nerve activity, although the f was the same. During controlled breathing at 0.10 Hz, the ratio of the low frequency (LF) to HF components (LF/HF), an index of sympathetic nerve activity, increased greatly and HF decreased, while heart rate and BP remained almost unchanged. Thus, controlled breathing at 0.25 Hz, which requires mental concentration, might inhibit parasympathetic nerve activity. During controlled breathing at 0.10 Hz, LF/HF increases because some HF subcomponents are synchronized with f and probably move into the LF band. This increment leads to misinterpretation of the true autonomic nervous regulation. We recommend that the respiratory pattern of participants should be evaluated before spectral HRV analysis to correctly understand changes in autonomic nervous regulation.

  2. Relationships between hippocampal activity and breathing patterns

    DEFF Research Database (Denmark)

    Harper, R M; Poe, G R; Rector, D M;


    Single cell discharge, EEG activity, and optical changes accompanying alterations in breathing patterns, as well as the knowledge that respiratory musculature is heavily involved in movement and other behavioral acts, implicate hippocampal regions in some aspects of breathing control. The control...

  3. Efficiency of Stereotactic Conformal Radiotherapy in Lung Metastases with Active Breathing Control

    Directory of Open Access Journals (Sweden)

    Olga Yu. Anikeeva, PhD


    Full Text Available Twenty four patients with lung metastases underwent radiosurgery treatment between October 2010 and December 2012. Stereotactic conformal high-dose radiation therapy with Active Breathing Control (ABC was conducted using the volumetric modulated arc therapy (VMAT technique. The median overall follow-up was 18 months (range 6-24 months, overall survival was 75%, and local control rate was 92%. The median time to progression was 4 months (range 1-18 months.There have been no cases of leucopenia, radiation esophagitis, mediastinitis or severe acute radiation pneumonitis. The late radiation effects Grade 2, according to the LENT SOMA scales, was observed in one patient (4%. The results of this study indicate that the usage of the stereotactic high-dose radiation therapy with ABC is safe and effective in the treatment of lung metastases.

  4. Advantage of using deep inspiration breath hold with active breathing control and image-guided radiation therapy for patients treated with lung cancers

    Directory of Open Access Journals (Sweden)

    KR Muralidhar


    Full Text Available Purpose: The aim of this study was to evaluate the irradiated volume and doses to the target, heart, left lung, right lung and spinal cord, the number of segments and treatment time by using moderated deep inspiration breath hold (mDIBH with active breathing control (ABC and image-guided radiotherapy (IGRT for patients treated with lung cancers.Methods: The suitability of this technique for lung patient treated with ABC was investigated and the solutions to achieve better treatments were discussed. Eleven lung cancer patients (3 left-sided and 8 right sided lesions with stages I-III underwent standard free breath (FB and ABC computed tomography (CT scans in the treatment supine position. This can be achieved by applying respiratory manoeuvres, such as mDIBH, during which the threshold volume utilized is defined as 75-80% of the maximum aspiratory capacity. Five to seven, 6-MV photon beams with optimized gantry angles were designed according to the tumor location to conform to the PTV while sparing as much heart, spinal cord, and contra lateral lung as possible. For eleven patients, treatment planning using mDIBH CT data with intensity modulated radiation therapy (IMRT was then reoptimized on the free breathing data set for comparison. The studied parameters of the plans for each patient were evaluated based on the average of the minimum, mean, and maximum difference in dose, the range of difference, and the p-value using two-tailed paired t test assuming equal variance.Results: The average volume of the planning target volume (PTV in 11 patients increased to 1.32% in ABC compared to FB. The average volume of heart in 11 patients decreased to 2.9% in ABC compared to free breathing IMRT. In the case of lungs, the volume increased to 27.5% and 25.85% for left and right lungs, respectively. The range of mean difference in dose to the PTV in 11 patients was -54 cGy to 230 cGy with ABC technique when compared with free breathing. The range of mean

  5. Coordination of breathing with nonrespiratory activities. (United States)

    Bartlett, Donald; Leiter, James C


    Many articles in this section of Comprehensive Physiology are concerned with the development and function of a central pattern generator (CPG) for the control of breathing in vertebrate animals. The action of the respiratory CPG is extensively modified by cortical and other descending influences as well as by feedback from peripheral sensory systems. The central nervous system also incorporates other CPGs, which orchestrate a wide variety of discrete and repetitive, voluntary and involuntary movements. The coordination of breathing with these other activities requires interaction and coordination between the respiratory CPG and those governing the nonrespiratory activities. Most of these interactions are complex and poorly understood. They seem to involve both conventional synaptic crosstalk between groups of neurons and fluid identity of neurons as belonging to one CPG or another: neurons that normally participate in breathing may be temporarily borrowed or hijacked by a competing or interrupting activity. This review explores the control of breathing as it is influenced by many activities that are generally considered to be nonrespiratory. The mechanistic detail varies greatly among topics, reflecting the wide variety of pertinent experiments.

  6. Information dynamics in cardiorespiratory analyses: application to controlled breathing. (United States)

    Widjaja, Devy; Faes, Luca; Montalto, Alessandro; Van Diest, Ilse; Marinazzo, Daniele; Van Huffel, Sabine


    Voluntary adjustment of the breathing pattern is widely used to deal with stress-related conditions. In this study, effects of slow and fast breathing with a low and high inspiratory to expiratory time on heart rate variability (HRV) are evaluated by means of information dynamics. Information transfer is quantified both as the traditional transfer entropy as well as the cross entropy, where the latter does not condition on the past of HRV, thereby taking the highly unidirectional relation between respiration and heart rate into account. The results show that the cross entropy is more suited to quantify cardiorespiratory information transfer as this measure increases during slow breathing, indicating the increased cardiorespiratory coupling and suggesting the shift towards vagal activation during slow breathing. Additionally we found that controlled breathing, either slow or fast, results as well in an increase in cardiorespiratory coupling, compared to spontaneous breathing, which demonstrates the beneficial effects of instructed breathing.

  7. Magnitude of shift of tumor position as a function of moderated deep inspiration breath-hold: An analysis of pooled data of lung patients with active breath control in image-guided radiotherapy

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    Muralidhar K


    Full Text Available The purpose of this study was to evaluate the reproducibility and magnitude of shift of tumor position by using active breathing control and iView-GT for patients with lung cancer with moderate deep-inspiration breath-hold (mDIBH technique. Eight patients with 10 lung tumors were studied. CT scans were performed in the breath-holding phase. Moderate deep-inspiration breath-hold under spirometer-based monitoring system was used. Few important bony anatomic details were delineated by the radiation oncologist. To evaluate the interbreath-hold reproducibility of the tumor position, we compared the digital reconstruction radiographs (DRRs from planning system with the DRRs from the iView-GT in the machine room. We measured the shift in x, y, and z directions. The reproducibility was defined as the difference between the bony landmarks from the DRR of the planning system and those from the DRR of the iView-GT. The maximum shift of the tumor position was 3.2 mm, 3.0 mm, and 2.9 mm in the longitudinal, lateral, and vertical directions. In conclusion, the moderated deep-inspiration breath-hold method using a spirometer is feasible, with relatively good reproducibility of the tumor position for image-guided radiotherapy in lung cancers.

  8. Controlled Frequency Breathing Reduces Inspiratory Muscle Fatigue. (United States)

    Burtch, Alex R; Ogle, Ben T; Sims, Patrick A; Harms, Craig A; Symons, Thorburn B; Folz, Rodney J; Zavorsky, Gerald S


    Controlled frequency breathing (CFB) is a common swim training modality involving holding one's breath for about 7 to 10 strokes before taking another breath. We sought to examine the effects of CFB training on reducing respiratory muscle fatigue. Competitive college swimmers were randomly divided into either the CFB group that breathed every 7 to 10 strokes, or a control group that breathed every 3-4 strokes. Twenty swimmers completed the study. The training intervention included 5-6 weeks (16 sessions) of 12x50-m repetitions with breathing 8-10 breaths per 50m (control group), or 2-3 breaths per 50-m (CFB group). Inspiratory muscle fatigue was defined as the decrease in maximal inspiratory mouth-pressure (MIP) between rest and 46s after a 200 yard free-style swimming race [115s (SD 7)]. Aerobic capacity, pulmonary diffusing capacity, and running economy were also measured pre and post-training. Pooled results demonstrated a 12% decrease in MIP at 46s post-race [-15 (SD 14) cm H2O, Effect size = -0.48, p training, only the CFB group prevented a decline in MIP values pre to 46 s post-race [-2 (13) cm H2O, p > 0.05]. However, swimming performance, aerobic capacity, pulmonary diffusing capacity, and running economy did not improve (p > 0.05) post-training in either group. In conclusion, CFB training appears to prevent inspiratory muscle fatigue yet no difference was found in performance outcomes.

  9. Decreased chewing activity during mouth breathing. (United States)

    Hsu, H-Y; Yamaguchi, K


    This study examined the effect of mouth breathing on the strength and duration of vertical effect on the posterior teeth using related functional parameters during 3 min of gum chewing in 39 nasal breathers. A CO(2) sensor was placed over the mouth to detect expiratory airflow. When no airflow was detected from the mouth throughout the recording period, the subject was considered a nasal breather and enrolled in the study. Electromyographic (EMG) activity was recorded during 3 min of gum chewing. The protocol was repeated with the nostrils occluded. The strength of the vertical effect was obtained as integrated masseter muscle EMG activity, and the duration of vertical effect was also obtained as chewing stroke count, chewing cycle variation and EMG activity duration above baseline. Baseline activity was obtained from the isotonic EMG activity during jaw movement at 1.6 Hz without making tooth contact. The duration represented the percentage of the active period above baseline relative to the 3-min chewing period. Paired t-test and repeated analysis of variance were used to compare variables between nasal and mouth breathing. The integrated EMG activity and the duration of EMG activity above baseline, chewing stroke count and chewing cycle significantly decreased during mouth breathing compared with nasal breathing (Pmouth breathing was significantly greater than nasal breathing (PMouth breathing reduces the vertical effect on the posterior teeth, which can affect the vertical position of posterior teeth negatively, leading to malocclusion.

  10. Breathing pattern, thoracoabdominal motion and muscular activity during three breathing exercises

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    G.M. Tomich


    Full Text Available The objective of the present study was to evaluate breathing pattern, thoracoabdominal motion and muscular activity during three breathing exercises: diaphragmatic breathing (DB, flow-oriented (Triflo II incentive spirometry and volume-oriented (Voldyne incentive spirometry. Seventeen healthy subjects (12 females, 5 males aged 23 ± 5 years (mean ± SD were studied. Calibrated respiratory inductive plethysmography was used to measure the following variables during rest (baseline and breathing exercises: tidal volume (Vt, respiratory frequency (f, rib cage contribution to Vt (RC/Vt, inspiratory duty cycle (Ti/Ttot, and phase angle (PhAng. Sternocleidomastoid muscle activity was assessed by surface electromyography. Statistical analysis was performed by ANOVA and Tukey or Friedman and Wilcoxon tests, with the level of significance set at P < 0.05. Comparisons between baseline and breathing exercise periods showed a significant increase of Vt and PhAng during all exercises, a significant decrease of f during DB and Voldyne, a significant increase of Ti/Ttot during Voldyne, and no significant difference in RC/Vt. Comparisons among exercises revealed higher f and sternocleidomastoid activity during Triflo II (P < 0.05 with respect to DB and Voldyne, without a significant difference in Vt, Ti/Ttot, PhAng, or RC/Vt. Exercises changed the breathing pattern and increased PhAng, a variable of thoracoabdominal asynchrony, compared to baseline. The only difference between DB and Voldyne was a significant increase of Ti/Ttot compared to baseline. Triflo II was associated with higher f values and electromyographic activity of the sternocleidomastoid. In conclusion, DB and Voldyne showed similar results while Triflo II showed disadvantages compared to the other breathing exercises.

  11. Thoracic radiotherapy and breath control: current prospects; Radiotherapie thoracique et controle de la respiration: perspectives actuelles

    Energy Technology Data Exchange (ETDEWEB)

    Reboul, F.; Mineur, L.; Paoli, J.B.; Bodez, V.; Oozeer, R.; Garcia, R. [Institut Sainte-Catherine, 84 - Avignon (France)


    Three-dimensional conformal radiotherapy (3D CRT) is adversely affected by setup error and organ motion. In thoracic 3D CRT, breathing accounts for most of intra-fraction movements, thus impairing treatment quality. Breath control clearly exhibits dosimetric improvement compared to free breathing, leading to various techniques for gated treatments. We review benefits of different breath control methods -i.e. breath-holding or beam gating, with spirometric, isometric or X-ray respiration sensor- and argument the choice of expiration versus inspiration, with consideration to dosimetric concerns. All steps of 3D-CRT can be improved with breath control. Contouring of organs at risk (OAR) and target are easier and more accurate on breath controlled CT-scans. Inter- and intra-fraction target immobilisation allows smaller margins with better coverage. Lung outcome predictors (NTCP, Mean Dose, LV20, LV30) are improved with breath-control. In addition, inspiration breath control facilitates beam arrangement since it widens the distance between OAR and target, and leaves less lung normal tissue within the high dose region. Last, lung density, as of CT scan, is more accurate, improving dosimetry. Our institutions choice is to use spirometry driven, patient controlled high-inspiration breath-hold; this technique gives excellent immobilization results, with high reproducibility, yet it is easy to implement and costs little extra treatment time. Breath control, whatever technique is employed, proves superior to free breathing treatment when using 3D-CRT. Breath control should then be used whenever possible, and is probably mandatory for IMRT. (authors)

  12. Mindfulness-of-breathing exercise modulates EEG alpha activity during cognitive performance. (United States)

    Bing-Canar, Hanaan; Pizzuto, Jacquelyne; Compton, Rebecca J


    The present study investigated whether engaging in a mindful breathing exercise would affect EEG oscillatory activity associated with self-monitoring processes, based on the notion that mindfulness enhances attentional awareness. Participants were assigned to either an audio exercise in mindful breathing or an audio control condition, and then completed a Stroop task while EEG was recorded. The primary EEG measure of interest was error-related alpha suppression (ERAS), an index of self-monitoring in which alpha power is reduced, suggesting mental engagement, following errors compared to correct responses. Participants in the mindful-breathing condition showed increased alpha power during the listening exercise and enhanced ERAS during the subsequent Stroop task. These results indicate enhanced error-monitoring among those in the mindful-breathing group.

  13. Characterising infant inter-breath interval patterns during active and quiet sleep using recurrence plot analysis. (United States)

    Terrill, Philip I; Wilson, Stephen J; Suresh, Sadasivam; Cooper, David M


    Breathing patterns are characteristically different between active and quiet sleep states in infants. It has been previously identified that breathing dynamics are governed by a non-linear controller which implies the need for a nonlinear analytical tool. Further, it has been shown that quantified nonlinear variables are different between adult sleep states. This study aims to determine whether a nonlinear analytical tool known as recurrence plot analysis can characterize breath intervals of active and quiet sleep states in infants. Overnight polysomnograms were obtained from 32 healthy infants. The 6 longest periods each of active and quiet sleep were identified and a software routine extracted inter-breath interval data for recurrence plot analysis. Determinism (DET), laminarity (LAM) and radius (RAD) values were calculated for an embedding dimension of 4, 6, 8 and 16, and fixed recurrence of 0.5, 1, 2, 3.5 and 5%. Recurrence plots exhibited characteristically different patterns for active and quiet sleep. Active sleep periods typically had higher values of RAD, DET and LAM than for quiet sleep, and this trend was invariant to a specific choice of embedding dimension or fixed recurrence. These differences may provide a basis for automated sleep state classification, and the quantitative investigation of pathological breathing patterns.

  14. Efficacy of device-guided breathing for hypertension in blinded, randomized, active-controlled trials : a meta-analysis of individual patient data

    NARCIS (Netherlands)

    Landman, Gijs W. D.; van Hateren, Kornelis J. J.; van Dijk, Peter R.; Logtenberg, Susan J. J.; Houweling, Sebastiaan T.; Groenier, Klaas H.; Bilo, Henk J. G.; Kleefstra, Nanne


    IMPORTANCE: Device-guided breathing (DGB) is recommended by the American Heart Association for its blood pressure-lowering effects. Most previous studies that showed beneficial effects on blood pressure had low methodological quality and only investigated short-term blood pressure effects. OBJECTIVE

  15. SU-E-T-426: Feasibility of Stereotactic Body Radiation Therapy (SBRT) Treatment of Pancreatic Cancer Using Volumetric Modulated Arc Therapy (VMAT) with Active Breathing Control (ABC)

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    Zhang, Y; Jackson, J; Davies, G; Herman, J; Forbang, R Teboh [John Hopkins University, Baltimore, MD (United States)


    Purpose: SBRT shows excellent tumor control and toxicity rates for patients with locally advanced pancreatic cancer (PCA). Herein, we evaluate the feasibility of using VMAT with ABC for PCA SBRT. Methods: Nine PCA patients previously treated via SBRT utilizing 11-beam step-and-shoot IMRT technique in our center were retrospectively identified, among whom eight patients received 3300cGy in 5 fractions while one received 3000cGy in 5 fractions. A VMAT plan was generated on each patient’s planning CT in Pinnacle v9.8 on Elekta Synergy following the same PCA SBRT clinical protocol. Three partial arcs (182°–300°, 300°-60°, and 60°-180°) with 2°/4° control-point spacing were used. The dosimetric difference between the VMAT and the original IMRT plans was analyzed. IMRT QA was performed for the VMAT plans using MapCheck2 in MapPHAN and the total delivery time was recorded. To mimic the treatment situation with ABC, where patients hold their breath for 20–30 seconds, the delivery was intentionally interrupted every 20–30 seconds. For each plan, the QA was performed with and without beam interruption. Gamma analysis (2%/2mm) was used to compare the planned and measured doses. Results: All VMAT plans with 2mm dose grid passed the clinic protocol with similar PTV coverage and OARs sparing, where PTV V-RxDose was 92.7±2.1% (VMAT) vs. 92.1±2.6% (IMRT), and proximal stomach V15Gy was 3.60±2.69 cc (VMAT) vs. 4.80±3.13 cc (IMRT). The mean total MU and delivery time of the VMAT plans were 2453.8±531.1 MU and 282.1±56.0 seconds. The gamma passing rates of absolute dose were 94.9±3.4% and 94.5±4.0% for delivery without and with interruption respectively, suggesting the dosimetry of VMAT delivery with ABC for SBRT won’t be compromised. Conclusion: This study suggests that PCA SBRT using VMAT with ABC is a feasible technique without compromising plan dosimetry. The combination of VMAT with ABC will potentially reduce the SBRT treatment time.

  16. Effect of mouth breathing on masticatory muscle activity during chewing food. (United States)

    Ikenaga, N; Yamaguchi, K; Daimon, S


    The aim of this study was to examine the effect of mouth breathing on masticatory muscle activity during chewing food. Masseter muscle activity during chewing of a rice ball was recorded in 45 adult volunteers (three women), identified as nose breathers. Surface electrodes were placed on the skin according to the orientation of the masseter muscle to record the activity of this muscle while the subjects chewed the food until swallowing. Each activity was recorded twice, once with nose breathing and once with mouth breathing induced by nasal obstruction. The integrated and mean electromyography values for mouth breathing were significantly lower than the values for nose breathing (P mouth breathing compared with nose breathing (P mouth breathing decreases chewing activity and reduces the vertical effect upon the posterior teeth.

  17. Does breathing type influence electromyographic activity of obligatory and accessory respiratory muscles? (United States)

    Gutiérrez, M F; Valenzuela, S; Miralles, R; Portus, C; Santander, H; Fuentes, A D; Celhay, I


    Craniomandibular electromyographic (EMG) studies frequently include several parameters, e.g. resting, chewing and tooth-clenching. EMG activity during these parameters has been recorded in the elevator muscles, but little is known about the respiratory muscles. The aim of this study was to compare EMG activity in obligatory and accessory respiratory muscles between subjects with different breathing types. Forty male subjects were classified according to their breathing type into two groups of 20 each: costo-diaphragmatic breathing type and upper costal breathing type. Bipolar surface electrodes were placed on the sternocleidomastoid, diaphragm, external intercostal and latissimus dorsi muscles. EMG activity was recorded during the following tasks: (i) normal quiet breathing, (ii) maximal voluntary clenching in intercuspal position, (iii) natural rate chewing until swallowing threshold, (iv) short-time chewing. Diaphragm EMG activity was significantly higher in the upper costal breathing type than in the costo-diaphragmatic breathing type in all tasks (P breathing type than in the costo-diaphragmatic breathing type in tasks 3 and 4 (P breathing types in the tasks studied (P > 0·05). The significantly higher EMG activity observed in subjects with upper costal breathing than in the costo-diaphragmatic breathing type suggests that there could be differences in motor unit recruitment strategies depending on the breathing type. This may be an expression of the adaptive capability of muscle chains in subjects who clinically have a different thoraco-abdominal expansion during inspiration at rest.

  18. An emerging role for gasotransmitters in the control of breathing and ionic regulation in fish. (United States)

    Perry, Steve; Kumai, Y; Porteus, C S; Tzaneva, V; Kwong, R W M


    Three gases comprising nitric oxide, carbon monoxide and hydrogen sulphide, collectively are termed gasotransmitters. The gasotransmitters control several physiological functions in fish by acting as intracellular signaling molecules. Hydrogen sulphide, first implicated in vasomotor control in fish, plays a critical role in oxygen chemoreception owing to its production and downstream effects within the oxygen chemosensory cells, the neuroepithelial cells. Indeed, there is emerging evidence that hydrogen sulphide may contribute to oxygen sensing in both fish and mammals by promoting membrane depolarization of the chemosensory cells. Unlike hydrogen sulphide which stimulates breathing in zebrafish, carbon monoxide inhibits ventilation in goldfish and zebrafish whereas nitric oxide stimulates breathing in zebrafish larvae while inhibiting breathing in adults. Gasotransmitters also modulate ionic uptake in zebrafish. Though nothing is known about the role of CO, reduced activities of branchial Na(+)/K(+)-ATPase and H(+)-ATPase activities in the presence of NO donors suggest an inhibitory role of NO in fish osmoregulation. Hydrogen sulphide inhibits Na(+) uptake in zebrafish larvae and contributes to lowering Na(+) uptake capacity in fish acclimated to Na(+)-enriched water whereas it stimulates Ca(2+) uptake in larvae exposed to Ca(2+)-poor water.

  19. Tumor, Lymph node and Lymph Node-to-Tumor Displacements over a Radiotherapy Series: Analysis of Inter- and Intrafraction Variations using Active Breathing Control (ABC) in Lung Cancer (United States)

    Weiss, Elisabeth; Robertson, Scott P.; Mukhopadhyay, Nitai; Hugo, Geoffrey D.


    Purpose To estimate errors in soft tissue-based image guidance due to relative changes between primary tumor (PT) and affected lymph node (LN) position and volume, and to compare the results to bony anatomy-based displacements of PTs and LNs during radiotherapy of lung cancer. Materials and Methods Weekly repeated breath hold CT scans were acquired in 17 lung cancer patients undergoing radiotherapy. PTs and affected LNs were manually contoured on all scans after rigid registration. Inter- and intrafraction displacements in the centers of mass of PTs and LNs relative to bone, and LNs relative to PTs (LN-PT) were calculated. Results The mean volume after 5 weeks was 65% for PTs and 63% for LNs. Systematic/random interfraction displacements were 2.6 – 4.6 mm/2.7 – 2.9 mm for PTs, 2.4 – 3.8 mm/1.4 – 2.7 mm for LNs, and 2.3 – 3.9 mm/1.9 – 2.8 mm for LN-PT. Systematic/random intrafraction displacements were 3 mm were observed in 67% of fractions and require a safety margin of 12 mm in lateral, 11 mm in anteroposterior and 9 mm in superior-inferior direction. LN-PT displacements displayed significant time trends (p<0.0001) and depended on the presence of pathoanatomical conditions of the ipsilateral lung, such as atelectasis. Conclusion Interfraction LN-PT displacements were mostly systematic and comparable to bony anatomy-based displacements of PTs or LNs alone. Time trends, large volume changes and the influence of pathoanatomical conditions underline the importance of soft tissue-based image guidance and the potential of plan adaptation. PMID:22197237

  20. A polynomial model of patient-specific breathing effort during controlled mechanical ventilation. (United States)

    Redmond, Daniel P; Docherty, Paul D; Yeong Shiong Chiew; Chase, J Geoffrey


    Patient breathing efforts occurring during controlled ventilation causes perturbations in pressure data, which cause erroneous parameter estimation in conventional models of respiratory mechanics. A polynomial model of patient effort can be used to capture breath-specific effort and underlying lung condition. An iterative multiple linear regression is used to identify the model in clinical volume controlled data. The polynomial model has lower fitting error and more stable estimates of respiratory elastance and resistance in the presence of patient effort than the conventional single compartment model. However, the polynomial model can converge to poor parameter estimation when patient efforts occur very early in the breath, or for long duration. The model of patient effort can provide clinical benefits by providing accurate respiratory mechanics estimation and monitoring of breath-to-breath patient effort, which can be used by clinicians to guide treatment.

  1. Autonomic control of post-air-breathing tachycardia in Clarias gariepinus (Teleostei: Clariidae). (United States)

    Teixeira, Mariana Teodoro; Armelin, Vinicius Araújo; Abe, Augusto Shinya; Rantin, Francisco Tadeu; Florindo, Luiz Henrique


    The African catfish (Clarias gariepinus) is a teleost with bimodal respiration that utilizes a paired suprabranchial chamber located in the gill cavity as an air-breathing organ. Like all air-breathing fishes studied to date, the African catfish exhibits pronounced changes in heart rate (f H) that are associated with air-breathing events. We acquired f H, gill-breathing frequency (f G) and air-breathing frequency (f AB) in situations that require or do not require air breathing (during normoxia and hypoxia), and we assessed the autonomic control of post-air-breathing tachycardia using an infusion of the β-adrenergic antagonist propranolol and the muscarinic cholinergic antagonist atropine. During normoxia, C. gariepinus presented low f AB (1.85 ± 0.73 AB h(-1)) and a constant f G (43.16 ± 1.74 breaths min(-1)). During non-critical hypoxia (PO2 = 60 mmHg), f AB in the African catfish increased to 5.42 ± 1.19 AB h(-1) and f G decreased to 39.12 ± 1.58 breaths min(-1). During critical hypoxia (PO2 = 20 mmHg), f AB increased to 7.4 ± 1.39 AB h(-1) and f G decreased to 34.97 ± 1.78 breaths min(-1). These results were expected for a facultative air breather. Each air breath (AB) was followed by a brief but significant tachycardia, which in the critical hypoxia trials, reached a maximum of 143 % of the pre-AB f H values of untreated animals. Pharmacological blockade allowed the calculation of cardiac autonomic tones, which showed that post-AB tachycardia is predominantly regulated by the parasympathetic subdivision of the autonomic nervous system.

  2. Breathing difficulties - first aid (United States)

    Difficulty breathing - first aid; Dyspnea - first aid; Shortness of breath - first aid ... Breathing difficulty is almost always a medical emergency. An exception is feeling slightly winded from normal activity, ...

  3. The modification of breathing behavior. Pavlovian and operant control in emotion and cognition. (United States)

    Ley, R


    The purpose of this article is to bring attention to breathing as a behavior that can be modified by means of Pavlovian and operant principles of control. With this aim in mind, this paper (a) reviews a selection of early and recent conditioning studies (Pavlovian and operant paradigms) in respiratory psychophysiology, (b) discusses the bidirectional relationship between breathing and emotion/cognition, and (c) discusses theoretical and applied implications that point to new directions for research in the laboratory and clinic. Emphasis is placed on dyspnea/suffocation fear and the acquisition of anticipatory dyspnea/suffocation fear in panic, anxiety, and stress disorders and their concomitant cognitive deficits. Discussions throughout the article focus on research relevant to theory and application, especially applications in programs of remedial breathing (breathing retraining) designed for the treatment of psychophysiological disorders (e.g., panic, anxiety, and stress) and the accompanying cognitive deficits that result from cerebral hypoxia induced by conditioned hyperventilation.

  4. Detection of response to command using voluntary control of breathing in disorders of consciousness (United States)

    Charland-Verville, Vanessa; Lesenfants, Damien; Sela, Lee; Noirhomme, Quentin; Ziegler, Erik; Chatelle, Camille; Plotkin, Anton; Sobel, Noam; Laureys, Steven


    Background: Detecting signs of consciousness in patients in a vegetative state/unresponsive wakefulness syndrome (UWS/VS) or minimally conscious state (MCS) is known to be very challenging. Plotkin et al. (2010) recently showed the possibility of using a breathing-controlled communication device in patients with locked in syndrome. We here aim to test a breathing-based “sniff controller” that could be used as an alternative diagnostic tool to evaluate response to command in severely brain damaged patients with chronic disorders of consciousness (DOC). Methods: Twenty-five DOC patients were included. Patients’ resting breathing-amplitude was measured during a 5 min resting condition. Next, they were instructed to end the presentation of a music sequence by sniffing vigorously. An automated detection of changes in breathing amplitude (i.e., >1.5 SD of resting) ended the music and hence provided positive feedback to the patient. Results: None of the 11 UWS/VS patients showed a sniff-based response to command. One out of 14 patients with MCS was able to willfully modulate his breathing pattern to answer the command on 16/19 trials (accuracy 84%). Interestingly, this patient failed to show any other motor response to command. Discussion: We here illustrate the possible interest of using breathing-dependent response to command in the detection of residual cognition in patients with DOC after severe brain injury. PMID:25566035

  5. Control of breathing by interacting pontine and pulmonary feedback loops

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    Yaroslav I Molkov


    Full Text Available The medullary respiratory network generates respiratory rhythm via sequential phase switching, which in turn is controlled by multiple feedbacks including those from the pons and nucleus tractus solitarii; the latter mediates pulmonary afferent feedback to the medullary circuits. It is hypothesized that both pontine and pulmonary feedback pathways operate via activation of medullary respiratory neurons that are critically involved in phase switching. Moreover, the pontine and pulmonary control loops interact, so that pulmonary afferents control the gain of pontine influence of the respiratory pattern. We used an established computational model of the respiratory network (Smith et al. J. Neurophysiol. 2007 and extended it by incorporating pontine circuits and pulmonary feedback. In the extended model, the pontine neurons receive phasic excitatory activation from, and provide feedback to, medullary respiratory neurons responsible for the onset and termination of inspiration. The model was used to study the effects of: (1 vagotomy (removal of pulmonary feedback, (2 suppression of pontine activity attenuating pontine feedback, and (3 these perturbations applied together on the respiratory pattern and durations of inspiration (TI and expiration (TE. In our model: (a the simulated vagotomy resulted in increases of both TI and TE, (b the suppression of pontine-medullary interactions led to the prolongation of TI at relatively constant, but variable TE, and (c these perturbations applied together resulted in apneusis, characterized by a significantly prolonged TI. The results of modeling were compared with, and provided a reasonable explanation for, multiple experimental data. The characteristic changes in TI and TE demonstrated with the model may represent characteristic changes in the balance between the pontine and pulmonary feedback control mechanisms that may reflect specific cardio-respiratory disorders and diseases.

  6. Breath alcohol ignition interlock devices: controlling the recidivist. (United States)

    Raub, Richard A; Lucke, Roy E; Wark, Richard I


    This study compares the recidivism rates of two groups of Illinois drivers who had their driver's licenses revoked for alcohol-impaired driving and who received restricted driving permits. Drivers in both groups had more than two driving under the influence (DUI) actions against their record within 5 years or were classed as level III alcohol dependents. Drivers in one group were required to install breath alcohol ignition interlock devices in their vehicles and drivers in the other group were not. The research found that drivers with the interlock were one-fifth as likely to be arrested for DUI during the 1 year the device was installed as the comparison group, which did not have the device. However, once the ignition interlock was removed, drivers in this group rapidly returned to DUI arrest rates similar to those in the comparison group. These findings echo previous literature. Additionally, the study showed that this voluntary program in Illinois reached only 16% of the drivers who met the requirements for installing the interlock device. Finally, this study found that individuals who were removed from the interlock program and returned to revoked status continued to drive. Within 3 years, approximately 50% of this latter group were involved in a crash or were arrested for DUI or with an invalid driver's license. Conclusions drawn from the study suggest that the breath alcohol ignition interlock device is effective in preventing continued driving while impaired. However, the large-scale effectiveness of the device is limited since most of the drivers eligible for the device do not have it installed. To have a significant impact, the interlock device must represent a better alternative to drivers whose licenses were suspended or revoked because of alcohol arrests compared to remaining on revoked status without having the device installed. Finally the research suggests that, given the rapid return to predevice recidivism, the devices should remain installed until

  7. Effects of Piracetam on Pediatric Breath Holding Spells: A Randomized Double Blind Controlled Trial



    How to cite this article:Abbaskhanian A, Ehteshami S, Sajjadi S, Rezai MS. Effects of Piracetam on Pediatric Breath Holding Spells: A Randomized Double Blind Controlled Trial. Iran J Child Neurol Autumn 2012; 6(4): 9-15. Abstarct:Objective Breath holding spells (BHS) are common paroxysmal non-epileptic eventsin the pediatric population which are very stressfull despite their harmlessnature. There has been no specific treatment found for the spells yet. The aimof this study was to evaluate the...

  8. CO[subscript 2] Rebreathing: An Undergraduate Laboratory to Study the Chemical Control of Breathing (United States)

    Domnik, N. J.; Turcotte, S. E.; Yuen, N. Y.; Iscoe, S.; Fisher, J. T.


    The Read CO[subscript]2 rebreathing method (Read DJ. "A clinical method for assessing the ventilatory response to carbon dioxide." "Australas Ann Med" 16: 20-32, 1967) provides a simple and reproducible approach for studying the chemical control of breathing. It has been widely used since the modifications made by Duffin and…

  9. Effects of Piracetam on Pediatric Breath Holding Spells: A Randomized Double Blind Controlled Trial

    Directory of Open Access Journals (Sweden)



    Full Text Available How to cite this article:Abbaskhanian A, Ehteshami S, Sajjadi S, Rezai MS. Effects of Piracetam on Pediatric Breath Holding Spells: A Randomized Double Blind Controlled Trial. Iran J Child Neurol Autumn 2012; 6(4: 9-15. Abstarct:Objective Breath holding spells (BHS are common paroxysmal non-epileptic eventsin the pediatric population which are very stressfull despite their harmlessnature. There has been no specific treatment found for the spells yet. The aimof this study was to evaluate the efficacy of piracetam (2-oxo-l-pyrrolidineon these children.Materials & MethodsIn this randomized double blind clinical trial study, 150 children with severe BHS referred to our pediatric outpatient service were enrolled from August2011 to July 2012. The patients were randomized into two equal groups.One received 40mg/kg/day piracetam and the other group received placebo,twice daily. Patients were followed monthly for three months. The numberof attacks/month before and after treatment were documented.ResultsOf the enrolled patients, 86 were boys. The mean age of the patients was17 months (range, 6 to 24 months. In the piracetam group, 1 month after treatment an 81% response to treatment was found. In the placebo group,none of the patients had complete remission and 7% of the cases had partialremission. Overall, control of breath-holding spells was observed in 91%of the patients in the group taking piracetam as compared with 16% in the group taking placebo at the end of the study. There wasd nosignificant difference detected between the groups regarding the prevalenceof drug side effects.ConclusionA significant difference was detected between piracetam and placebo in prevention and controlling BHS. Piracetam (40mg/kg/day had a good effecton our patients. ReferencesDi Mario FJ Jr. Prospective study of children with cyanotic and pallid breath-holding spells. Pediatrics. 2001 Feb;107(2:265-9.Kotagal P, Costa M, Wyllie E, Wolgamuth B. Paroxysmal non epileptic

  10. Optical Breath Gas Sensor for Extravehicular Activity Application (United States)

    Wood, William R.; Casias, Miguel E.; Vakhtin, Andrei B.; Pilgrim, Jeffrey S.; Chullen, Cinda; Falconi, Eric A.; McMillin, Summer


    The function of the infrared gas transducer used during extravehicular activity in the current space suit is to measure and report the concentration of carbon dioxide (CO2) in the ventilation loop. The next generation portable life support system (PLSS) requires next generation CO2 sensing technology with performance beyond that presently in use on the Space Shuttle/International Space Station extravehicular mobility unit (EMU). Accommodation within space suits demands that optical sensors meet stringent size, weight, and power requirements. A laser diode spectrometer based on wavelength modulation spectroscopy is being developed for this purpose by Vista Photonics, Inc. Two prototype devices were delivered to NASA Johnson Space Center (JSC) in September 2011. The sensors incorporate a laser diode-based CO2 channel that also includes an incidental water vapor (humidity) measurement and a separate oxygen channel using a vertical cavity surface emitting laser. Both prototypes are controlled digitally with a field-programmable gate array/microcontroller architecture. The present development extends and upgrades the earlier hardware to the Advanced PLSS 2.0 test article being constructed and tested at JSC. Various improvements to the electronics and gas sampling are being advanced by this project. The combination of low power electronics with the performance of a long wavelength laser spectrometer enables multi-gas sensors with significantly increased performance over that presently offered in the EMU.

  11. Voluntary control of breathing does not alter vagal modulation of heart rate (United States)

    Patwardhan, A. R.; Evans, J. M.; Bruce, E. N.; Eckberg, D. L.; Knapp, C. F.


    Variations in respiratory pattern influence the heart rate spectrum. It has been suggested, hence, that metronomic respiration should be used to correctly assess vagal modulation of heart rate by using spectral analysis. On the other hand, breathing to a metronome has been reported to increase heart rate spectral power in the high- or respiratory frequency region; this finding has led to the suggestion that metronomic respiration enhances vagal tone or alters vagal modulation of heart rate. To investigate whether metronomic breathing complicates the interpretation of heart rate spectra by altering vagal modulation, we recorded the electrocardiogram and respiration from eight volunteers during three breathing trials of 10 min each: 1) spontaneous breathing (mean rate of 14.4 breaths/min); 2) breathing to a metronome at the rate of 15, 18, and 21 breaths/min for 2, 6, and 2 min, respectively; and 3) breathing to a metronome at the rate of 18 breaths/min for 10 min. Data were also collected from eight volunteers who breathed spontaneously for 20 min and breathed metronomically at each subject's mean spontaneous breathing frequency for 20 min. Results from the three 10-min breathing trials showed that heart rate power in the respiratory frequency region was smaller during metronomic breathing than during spontaneous breathing. This decrease could be explained fully by the higher breathing frequencies used during trials 2 and 3 of metronomic breathing. When the subjects breathed metronomically at each subject's mean breathing frequency, the heart rate powers during metronomic breathing were similar to those during spontaneous breathing. Our results suggest that vagal modulation of heart rate is not altered and vagal tone is not enhanced during metronomic breathing.

  12. Role of atrial receptors in the control of sodium excretion. [pressure breathing and antinatiuretic effects in dogs (United States)

    Meehan, J. R.; Henry, J. P.


    Responses of an innervated and a contralateral chronically denervated kidney to mild positive pressure breathing are compared for saline volume expansions in chloralose anesthetized dogs. It is shown that mild pressure breathing significantly reduces sodium excretion, urine flow, free water clearance, and PAH clearance. After 20 minutes of positive pressure breathing, both kidney responses are identical suggesting the release of natriuretic hormone which reduces renal function in addition to the demonstrated change in renal nerve activity. Increase of the left atrial pressure through balloon obstruction of the mitral orifice increases urine flow, sodium excretion and PAH clearance; inflation of the balloon and positive pressure breathing again depresses renal function. Preliminary evidence indicates that receptors in the right atrium are more severely affected by pressure breathing than those in the left atrium.

  13. Abdominal muscle activity during breathing in different postures in COPD "Stage 0" and healthy subjects. (United States)

    Mesquita Montes, António; Maia, Joana; Crasto, Carlos; de Melo, Cristina Argel; Carvalho, Paulo; Santos, Rita; Pereira, Susana; Vilas-Boas, João Paulo


    This study aims to evaluate the effect of different postures on the abdominal muscle activity during breathing in subjects "at risk" for the development of chronic obstructive pulmonary disease (COPD) and healthy. Twenty-nine volunteers, divided in "At Risk" for COPD (n=16; 47.38±5.08years) and Healthy (n=13; 47.54±6.65years) groups, breathed at the same rhythm in supine, standing, tripod and 4-point-kneeling positions. Surface electromyography was performed to assess the activation intensity of rectus abdominis, external oblique and transversus abdominis/internal oblique (TrA/IO) muscles, during inspiration and expiration. From supine to standing, an increased activation of all abdominal muscles was observed in "At Risk" for COPD group; however, in Healthy group, TrA/IO muscle showed an increased activation. In both groups, the TrA/IO muscle activation in tripod and 4-point kneeling positions was higher than in supine and lower than in standing. Subjects "at risk" for the development of COPD seemed to have a specific recruitment of the superficial layer of ventrolateral abdominal wall for the synchronization of postural function and mechanics of breathing.

  14. Abdominal muscle activity during breathing with and without inspiratory and expiratory loads in healthy subjects. (United States)

    Mesquita Montes, António; Baptista, João; Crasto, Carlos; de Melo, Cristina Argel; Santos, Rita; Vilas-Boas, João Paulo


    Central Nervous System modulates the motor activities of all trunk muscles to concurrently regulate the intra-abdominal and intra-thoracic pressures. The study aims to evaluate the effect of inspiratory and expiratory loads on abdominal muscle activity during breathing in healthy subjects. Twenty-three higher education students (21.09±1.56years; 8males) breathed at a same rhythm (inspiration: two seconds; expiration: four seconds) without load and with 10% of the maximal inspiratory or expiratory pressures, in standing. Surface electromyography was performed to assess the activation intensity of rectus abdominis, external oblique and transversus abdominis/internal oblique muscles, during inspiration and expiration. During inspiration, transversus abdominis/internal oblique activation intensity was significantly lower with inspiratory load when compared to without load (p=0.009) and expiratory load (p=0.002). During expiration, the activation intensity of all abdominal muscles was significantly higher with expiratory load when compared to without load (pmuscle to modulate the intra-abdominal pressure for the breathing mechanics.

  15. Controlled-frequency breath swimming improves swimming performance and running economy. (United States)

    Lavin, K M; Guenette, J A; Smoliga, J M; Zavorsky, G S


    Respiratory muscle fatigue can negatively impact athletic performance, but swimming has beneficial effects on the respiratory system and may reduce susceptibility to fatigue. Limiting breath frequency during swimming further stresses the respiratory system through hypercapnia and mechanical loading and may lead to appreciable improvements in respiratory muscle strength. This study assessed the effects of controlled-frequency breath (CFB) swimming on pulmonary function. Eighteen subjects (10 men), average (standard deviation) age 25 (6) years, body mass index 24.4 (3.7) kg/m(2), underwent baseline testing to assess pulmonary function, running economy, aerobic capacity, and swimming performance. Subjects were then randomized to either CFB or stroke-matched (SM) condition. Subjects completed 12 training sessions, in which CFB subjects took two breaths per length and SM subjects took seven. Post-training, maximum expiratory pressure improved by 11% (15) for all 18 subjects (P inspiratory pressure was unchanged. Running economy improved by 6 (9)% in CFB following training (P swimmers.

  16. Continuous high order sliding mode controller design for a flexible air-breathing hypersonic vehicle. (United States)

    Wang, Jie; Zong, Qun; Su, Rui; Tian, Bailing


    This paper investigates the problem of tracking control with uncertainties for a flexible air-breathing hypersonic vehicle (FAHV). In order to overcome the analytical intractability of this model, an Input-Output linearization model is constructed for the purpose of feedback control design. Then, the continuous finite time convergence high order sliding mode controller is designed for the Input-Output linearization model without uncertainties. In addition, a nonlinear disturbance observer is applied to estimate the uncertainties in order to compensate the controller and disturbance suppression, where disturbance observer and controller synthesis design is obtained. Finally, the synthesis of controller and disturbance observer is used to achieve the tracking for the velocity and altitude of the FAHV and simulations are presented to illustrate the effectiveness of the control strategies.

  17. Blood pressure regulation, autonomic control and sleep disordered breathing in children. (United States)

    Nisbet, Lauren C; Yiallourou, Stephanie R; Walter, Lisa M; Horne, Rosemary S C


    Sleep disordered breathing (SDB) ranges in severity from primary snoring (PS) to obstructive sleep apnoea (OSA). In adults, SDB is associated with adverse cardiovascular consequences which are mediated, in part, by autonomic dysfunction. Although SDB is common in children, fewer paediatric studies have investigated these cardiovascular effects. Initial research focused on those with OSA, indeed children with PS were occasionally utilised as the comparison control group. However, it is essential to understand the ramifications of this disorder in all its severities, as currently the milder forms of SDB are often untreated. Methodologies used to assess autonomic function in children with SDB include blood pressure (BP), BP variability, baroreflex sensitivity, heart rate variability, peripheral arterial tonometry and catecholamine assays. The aim of this review was to summarise the findings of paediatric studies to date and explore the relationship between autonomic dysfunction and SDB in children, paying particular attention to the roles of disease severity and/or age. This review found evidence of autonomic dysfunction in children with SDB during both wakefulness and sleep. BP dysregulation, elevated generalised sympathetic activity and impairment of autonomic reflexes occur in school-aged children and adolescents with SDB. The adverse effects of SDB seem somewhat less in young children, although more studies are needed. There is mounting evidence that the cardiovascular and autonomic consequences of SDB are not limited to those with OSA, but are also evident in children with PS. The severity of disease and age of onset of autonomic consequences may be important guides for the treatment of SDB.

  18. pH in exhaled breath condensate and nasal lavage as a biomarker of air pollution-related inflammation in street traffic-controllers and office-workers

    Directory of Open Access Journals (Sweden)

    Thamires Marques de Lima


    Full Text Available OBJECTIVE: To utilize low-cost and simple methods to assess airway and lung inflammation biomarkers related to air pollution. METHODS: A total of 87 male, non-smoking, healthy subjects working as street traffic-controllers or office-workers were examined to determine carbon monoxide in exhaled breath and to measure the pH in nasal lavage fluid and exhaled breath condensate. Air pollution exposure was measured by particulate matter concentration, and data were obtained from fixed monitoring stations (8-h work intervals per day, during the 5 consecutive days prior to the study. RESULTS: Exhaled carbon monoxide was two-fold greater in traffic-controllers than in office-workers. The mean pH values were 8.12 in exhaled breath condensate and 7.99 in nasal lavage fluid in office-workers; these values were lower in traffic-controllers (7.80 and 7.30, respectively. Both groups presented similar cytokines concentrations in both substrates, however, IL-1β and IL-8 were elevated in nasal lavage fluid compared with exhaled breath condensate. The particulate matter concentration was greater at the workplace of traffic-controllers compared with that of office-workers. CONCLUSION: The pH values of nasal lavage fluid and exhaled breath condensate are important, robust, easy to measure and reproducible biomarkers that can be used to monitor occupational exposure to air pollution. Additionally, traffic-controllers are at an increased risk of airway and lung inflammation during their occupational activities compared with office-workers.

  19. Novel adaptive neural control of flexible air-breathing hypersonic vehicles based on sliding mode differentiator

    Directory of Open Access Journals (Sweden)

    Bu Xiangwei


    Full Text Available A novel adaptive neural control strategy is exploited for the longitudinal dynamics of a generic flexible air-breathing hypersonic vehicle (FAHV. By utilizing functional decomposition method, the dynamics of FAHV is decomposed into the velocity subsystem and the altitude subsystem. For each subsystem, only one neural network is employed for the unknown function approximation. To further reduce the computational burden, minimal-learning parameter (MLP technology is used to estimate the norm of ideal weight vectors rather than their elements. By introducing sliding mode differentiator (SMD to estimate the newly defined variables, there is no need for the strict-feedback form and virtual controller. Hence the developed control law is considerably simpler than the ones derived from back-stepping scheme. Finally, simulation studies are made to illustrate the effectiveness of the proposed control approach in spite of the flexible effects, system uncertainties and varying disturbances.

  20. Robust tracking control design for a flexible air-breathing hypersonic vehicle

    Institute of Scientific and Technical Information of China (English)

    张垚; 鲜斌; 刁琛; 赵勃; 郭建川


    A nonlinear robust controller was presented to improve the tracking control performance of a flexible air-breathing hypersonic vehicle (AHV) which is subjected to system parametric uncertainties and unknown additive time-varying disturbances. The longitudinal dynamic model for the flexible AHV was used for the control development. High-gain observers were designed to compensate for the system uncertainties and additive disturbances. Small gain theorem and Lyapunov based stability analysis were utilized to prove the stability of the closed loop system. Locally uniformly ultimately bounded tracking of the vehicle’s velocity, altitude and attack angle were achieved under aeroelastic effects, system parametric uncertainties and unknown additive disturbances. Matlab/Simulink simulation results were provided to validate the robustness of the proposed control design. The simulation results demonstrate that the tracking errors stay in a small region around zero.

  1. Adaptive Neural Back-Stepping Control with Constrains for a Flexible Air-Breathing Hypersonic Vehicle

    Directory of Open Access Journals (Sweden)

    Pengfei Wang


    Full Text Available The design of an adaptive neural back-stepping control for a flexible air-breathing hypersonic vehicle (AHV in the presence of input constraint and aerodynamic uncertainty is discussed. Based on functional decomposition, the dynamics can be decomposed into the velocity subsystem and the altitude subsystem. To guarantee the exploited controller’s robustness with respect to parametric uncertainties, neural network (NN is applied to approximate the lumped uncertainty of each subsystem of AHV model. The exceptional contribution is that novel auxiliary systems are introduced to compensate both the tracking errors and desired control laws, based on which the explored controller can still provide effective tracking of velocity and altitude commands when the actuators are saturated. Finally, simulation studies are made to illustrate the effectiveness of the proposed control approach in spite of the flexible effects, system uncertainties, and varying disturbances.

  2. Rapid eye movement sleep in breath holders. (United States)

    Kohyama, J; Hasegawa, T; Shimohira, M; Fukumizu, M; Iwakawa, Y


    One-night polysomnography was performed on seven subjects suffering from breath-holding spells, including one whose death was suggested to be a consequence of a breath-holding spell. The fatal case showed no rapid eye movements (REMs) during REM sleep, although he exhibited REMs during wakefulness. The average numbers of both REMs and bursts of REMs in REM sleep in the other six breath holders were significantly lower than those in age-matched controls. The breath holders showed no airway obstruction, desaturation, or sleep fragmentation. Since the rapid ocular activity in REM sleep is generated in the brain stem, we hypothesized that a functional brainstem disturbance is involved in the occurrence of breath-holding spells.

  3. Nocturnal bruxing events in subjects with sleep-disordered breathing and control subjects. (United States)

    Okeson, J P; Phillips, B A; Berry, D T; Cook, Y R; Cabelka, J F


    Nocturnal bruxing events were recorded during a single night of sleep for 12 subjects with sleep-disordered breathing and 12 age- and sex-matched controls. The results suggest that bruxing events are very common in both groups and are closely associated with sleep arousals. There were few differences in the number, duration, or type of bruxing events between these two groups. Bruxing events were common during stage 1, stage 2, and REM sleep, while they rarely occurred during stage 3 and 4 sleep. The average duration of bruxing events ranged from 3.82 to 6.68 seconds. There was a trend toward more bruxing events occurring while sleeping on the back than on the side.

  4. Effects of Piracetam on Pediatric Breath Holding Spells: A Randomized Double Blind Controlled Trial

    Directory of Open Access Journals (Sweden)

    Mohammad Sadegh REZAI


    Full Text Available ObjectiveBreath holding spells (BHS are common paroxysmal non-epileptic events in the pediatric population which are very stressful despite their harmless nature. There has been no specific treatment found for the spells yet. The aim of this study was to evaluate the efficacy of piracetam (2-oxo-l-pyrrolidineon these children.Materials & MethodsIn this randomized double blind clinical trial study, 150 children with severe BHS referred to our pediatric outpatient service were enrolled from August 2011 to July 2012. The patients were randomized into two equal groups.One received 40mg/kg/day piracetam and the other group received placebo,twice daily. Patients were followed monthly for three months. The number of attacks/month before and after treatment were documented.Results Of the enrolled patients, 86 were boys. The mean age of the patients was 17 months (range, 6 to 24 months. In the piracetam group, 1 month after treatment an 81% response to treatment was found. In the placebo group,none of the patients had complete remission and 7% of the cases had partial remission. Overall, control of breath-holding spells was observed in 91%of the patients in the group taking piracetam as compared with 16% in the group taking placebo at the end of the study. There was nosignificant difference detected between the groups regarding the prevalence of drug side effects.ConclusionA significant difference was detected between piracetam and placebo in prevention and controlling BHS. Piracetam (40mg/kg/day had a good effect on our patients.

  5. Neural mechanisms underlying breathing complexity.

    Directory of Open Access Journals (Sweden)

    Agathe Hess

    Full Text Available Breathing is maintained and controlled by a network of automatic neurons in the brainstem that generate respiratory rhythm and receive regulatory inputs. Breathing complexity therefore arises from respiratory central pattern generators modulated by peripheral and supra-spinal inputs. Very little is known on the brainstem neural substrates underlying breathing complexity in humans. We used both experimental and theoretical approaches to decipher these mechanisms in healthy humans and patients with chronic obstructive pulmonary disease (COPD. COPD is the most frequent chronic lung disease in the general population mainly due to tobacco smoke. In patients, airflow obstruction associated with hyperinflation and respiratory muscles weakness are key factors contributing to load-capacity imbalance and hence increased respiratory drive. Unexpectedly, we found that the patients breathed with a higher level of complexity during inspiration and expiration than controls. Using functional magnetic resonance imaging (fMRI, we scanned the brain of the participants to analyze the activity of two small regions involved in respiratory rhythmogenesis, the rostral ventro-lateral (VL medulla (pre-Bötzinger complex and the caudal VL pons (parafacial group. fMRI revealed in controls higher activity of the VL medulla suggesting active inspiration, while in patients higher activity of the VL pons suggesting active expiration. COPD patients reactivate the parafacial to sustain ventilation. These findings may be involved in the onset of respiratory failure when the neural network becomes overwhelmed by respiratory overload We show that central neural activity correlates with airflow complexity in healthy subjects and COPD patients, at rest and during inspiratory loading. We finally used a theoretical approach of respiratory rhythmogenesis that reproduces the kernel activity of neurons involved in the automatic breathing. The model reveals how a chaotic activity in

  6. Diaphragmatic amplitude and accessory inspiratory muscle activity in nasal and mouth-breathing adults: a cross-sectional study. (United States)

    Trevisan, Maria Elaine; Boufleur, Jalusa; Soares, Juliana Corrêa; Haygert, Carlos Jesus Pereira; Ries, Lilian Gerdi Kittel; Corrêa, Eliane Castilhos Rodrigues


    The purpose of this study was to evaluate the electromyographic activity of the accessory inspiratory muscles and the diaphragmatic amplitude (DA) in nasal and mouth-breathing adults. The study evaluated 38 mouth-breathing (MB group) and 38 nasal-breathing (NB group) adults, from 18 to 30years old and both sexes. Surface electromyography (sEMG) was used to evaluate the amplitude and symmetry (POC%) of the sternocleidomastoid (SCM) and upper trapezius (UT) muscles at rest, during nasal slow inspiration at Lung Total Capacity (LTC) and, during rapid and abrupt inspiration: Sniff, Peak Nasal Inspiratory Flow (PNIF) and Maximum Inspiratory Pressure (MIP). M-mode ultrasonography assessed the right diaphragm muscle amplitude in three different nasal inspirations: at tidal volume (TV), Sniff and inspiration at LTC. The SCM activity was significantly lower in the MB group during Sniff, PNIF (pMouth breathing reflected on lower recruitment of the accessory inspiratory muscles during fast inspiration and lower diaphragmatic amplitude, compared to nasal breathing.

  7. Prevalence of sleep-disordered breathing in elderly patients with cardiac pacemaker: a case-control study

    Institute of Scientific and Technical Information of China (English)

    Haiyun WU; Shiwen WANG; Jianping JIA; Wenli ZHANG; Qiang XU


    Objective To investigate the prevalence of sleep-disordered breathing in elderly patients with permanent cardiac pacemaker implantation due to bradyarrhythmias, and the relationship between pacing mode and patients' sleep apnea-hypopnea index.Methods Forty-four elderly patients (>60 years) with cardiac pacemaker and their 44 controls matched for gender, age, body mass index and cardiovascular morbidity were studied using polysomnography or portable sleep monitoring device. Results Prevalence of sleep-disordered breathing (apnea-hypopnea index ≥5/h) was 44.7% and the mean apnea-hypopnea index was 8.2 ±4.1/h in the cardiac pacemaker group, which were significantly higher than those in control subjects (25% and 4.6±2.4/h, respectively, P<0.01 and P<0.05). The mean apnea-hypopnea index of patients with DDD or AAI pacemaker was significantly lower than that of patients with VVI pacemaker. Conclusions Sleep-disordered breathing was more common in patients who had their cardiac pacemaker implanted due to bradyarrhythmias than in their matched controls. Compared with VVI pacing, DDD or AAI pacing may be more beneficial to patients with bradyarrhythmias and sleep-disordered breathing.

  8. Breathing Problems (United States)

    ... getting enough air. Sometimes you can have mild breathing problems because of a stuffy nose or intense ... panic attacks Allergies If you often have trouble breathing, it is important to find out the cause.

  9. Early postoperative erythromycin breath test correlates with hepatic cytochrome P4503A activity in liver transplant recipients

    DEFF Research Database (Denmark)

    Schmidt, L E; Olsen, A K; Stentoft, K;


    milligram of protein, and the activity determined by testosterone 6beta-hydroxylation ranged from 0.030 to 0.627 nmol per minute per milligram of protein. Significant correlation was demonstrated between the erythromycin breath test and both the erythromycin demethylation (Spearman correlation coefficient......: R = 0.76, R (2) = 0.57; P =.0004) and the testosterone 6beta-hydroxylation (Spearman correlation coefficient: R = 0.79, R (2) = 0.63; P =.0001) assays. The erythromycin breath test also correlated with the CYP3A protein level (Spearman correlation coefficient: R = 0.60, R (2) = 0.36; P =.01...

  10. Non-invasive detection of low-intestinal lactase activity in children by use of a combined (CO2)-C-13/H-2 breath test

    NARCIS (Netherlands)

    Koetse, HA; Stellaard, F; Bijleveld, CMA; Elzinga, H; Boverhof, R; van der Meer, R; Vonk, RJ; Sauer, PJJ


    Background: The aim of the study was to diagnose hypolactasia with a higher accuracy than with the traditional H-2 breath test. Methods: We used a combined C-13-lactose (CO2)-C-13/H-2 breath test, which was performed in 33 patients in whom lactase activity was measured. Results: Lactase activity was

  11. Perspective: Crowd-based breath analysis: assessing behavior, activity, exposures, and emotional response of people in groups (United States)

    A new concept for exhaled breath analysis has emerged wherein groups, or even crowds of people are simultaneously sampled in enclosed environments to detect overall trends in their activities and recent exposures. The basic idea is to correlate the temporal profile of known breat...

  12. Control of breathing and the circulation in high-altitude mammals and birds. (United States)

    Ivy, Catherine M; Scott, Graham R


    Hypoxia is an unremitting stressor at high altitudes that places a premium on oxygen transport by the respiratory and cardiovascular systems. Phenotypic plasticity and genotypic adaptation at various steps in the O2 cascade could help offset the effects of hypoxia on cellular O2 supply in high-altitude natives. In this review, we will discuss the unique mechanisms by which ventilation, cardiac output, and blood flow are controlled in high-altitude mammals and birds. Acclimatization to high altitudes leads to some changes in respiratory and cardiovascular control that increase O2 transport in hypoxia (e.g., ventilatory acclimatization to hypoxia). However, acclimatization or development in hypoxia can also modify cardiorespiratory control in ways that are maladaptive for O2 transport. Hypoxia responses that arose as short-term solutions to O2 deprivation (e.g., peripheral vasoconstriction) or regional variation in O2 levels in the lungs (i.e., hypoxic pulmonary vasoconstriction) are detrimental at in chronic high-altitude hypoxia. Evolved changes in cardiorespiratory control have arisen in many high-altitude taxa, including increases in effective ventilation, attenuation of hypoxic pulmonary vasoconstriction, and changes in catecholamine sensitivity of the heart and systemic vasculature. Parallel evolution of some of these changes in independent highland lineages supports their adaptive significance. Much less is known about the genomic bases and potential interactive effects of adaptation, acclimatization, developmental plasticity, and trans-generational epigenetic transfer on cardiorespiratory control. Future work to understand these various influences on breathing and circulation in high-altitude natives will help elucidate how complex physiological systems can be pushed to their limits to maintain cellular function in hypoxia.

  13. Polymeric microtubules that breathe: CO2 -driven polymer controlled-self-assembly and shape transformation. (United States)

    Yan, Qiang; Zhao, Yue


    Tubular breathing motion: Polymer tubules self-assembled from a gas-sensitive triblock copolymer can undergo shape evolution. A sequence from microtubes through submicroscopic vesicles to nanosized spherical micelles is modulated by CO2 stimulation levels.

  14. Comparative analysis of selected exhaled breath biomarkers obtained with two different temperature-controlled devices

    Directory of Open Access Journals (Sweden)

    Brüning Thomas


    Full Text Available Abstract Background The collection of exhaled breath condensate (EBC is a suitable and non-invasive method for evaluation of airway inflammation. Several studies indicate that the composition of the condensate and the recovery of biomarkers are affected by physical characteristics of the condensing device and collecting circumstances. Additionally, there is an apparent influence of the condensing temperature, and often the level of detection of the assay is a limiting factor. The ECoScreen2 device is a new, partly single-use disposable system designed for studying different lung compartments. Methods EBC samples were collected from 16 healthy non-smokers by using the two commercially available devices ECoScreen2 and ECoScreen at a controlled temperature of -20°C. EBC volume, pH, NOx, LTB4, PGE2, 8-isoprostane and cys-LTs were determined. Results EBC collected with ECoScreen2 was less acidic compared to ECoScreen. ECoScreen2 was superior concerning condensate volume and detection of biomarkers, as more samples were above the detection limit (LTB4 and PGE2 or showed higher concentrations (8-isoprostane. However, NOx was detected only in EBC sampled by ECoScreen. Conclusion ECoScreen2 in combination with mediator specific enzyme immunoassays may be suitable for measurement of different biomarkers. Using this equipment, patterns of markers can be assessed that are likely to reflect the complex pathophysiological processes in inflammatory respiratory disease.

  15. Breath-synchronized plume-control inhaler for pulmonary delivery of fluticasone propionate. (United States)

    Shrewsbury, Stephen B; Armer, Thomas A; Newman, Stephen P; Pitcairn, Gary


    A novel breath-synchronized, plume-control inhaler (Tempo inhaler) was developed to overcome limitations of a pressurized metered-dose inhaler. This report compared the Tempo inhaler and a commercial inhaler for fine particle distribution and lung deposition of fluticasone propionate. In vitro fine particle distribution was determined using the Andersen Cascade Impactor at inspiration rates of 28.3 and 45L/min. In vivo lung deposition was assessed in a randomized, two-arm, crossover study of (99m)Tc-radiolabeled fluticasone propionate in 12 healthy adult subjects, analyzed by gamma scintigraphy. In vitro: fine particle fractions at 28.3 and 45L/min were 88.6+/-3.6% and 89.2+/-3.0% (Tempo inhaler) versus 40.4+/-4.7% and 43.1+/-4.4% (commercial inhaler). In vivo: lung deposition was 41.5+/-9.8% (Tempo inhaler) versus 13.8+/-7.4% (commercial inhaler) and oropharyngeal deposition was 18.3+/-7.7% (Tempo inhaler) versus 76.8+/-7.1% (commercial inhaler). Variability of lung deposition was reduced from 55% (commercial inhaler) to 24% (Tempo inhaler) of the delivered dose. The Tempo inhaler produced significantly higher fine particle fraction values, reduced oropharyngeal deposition by 75%, and increased whole, central, intermediate, and peripheral lung delivery by more than 200%. Thus, the Tempo inhaler enhances efficient drug delivery to the lungs.

  16. Control of breathing in African lungfish (Protopterus dolloi): A comparison of aquatic and cocooned (terrestrialized) animals

    DEFF Research Database (Denmark)

    Perry, S.F.; Euverman, R.; Wang, Tobias


    African lungfish, Protopterus dolloi exhibited constant rates of O2 consumption before (0.95 ± 0.07 mmol kg-1 h-1), during (1.21 ± 0.32 mmol kg-1 h-1) and after (1.14 ± 0.14 mmol kg-1 h-1) extended periods (1-2 months) of terrestrialization while cocooned. Although a breathing event...... in terrestrialized fish consisted of multiple bouts of inspiration and expiration in rapid succession, the mean frequency of pulmonary breathing events was unaltered in the terrestrialized fish (16.7 ± 1.4 h-1 versus 20.1 ± 4.9 h-1 in the aquatic and terrestrialized fish, respectively). Hypoxia ( 20 mmHg) increased...... the frequency of breathing events by 16 and 23 h-1 in the aquatic and terrestrialized fish, respectively. Hyperoxia ( 550 mmHg) decreased breathing event frequency by 10 and 15 h-1 in the aquatic and terrestrialized animals. Aquatic hypercapnia ( 37.5 mmHg) increased pulmonary breathing frequency (from 15...

  17. From breathing to respiration. (United States)

    Fitting, Jean-William


    The purpose of breathing remained an enigma for a long time. The Hippocratic school described breathing patterns but did not associate breathing with the lungs. Empedocles and Plato postulated that breathing was linked to the passage of air through pores of the skin. This was refuted by Aristotle who believed that the role of breathing was to cool the heart. In Alexandria, breakthroughs were accomplished in the anatomy and physiology of the respiratory system. Later, Galen proposed an accurate description of the respiratory muscles and the mechanics of breathing. However, his heart-lung model was hampered by the traditional view of two non-communicating vascular systems - veins and arteries. After a period of stagnation in the Middle Ages, knowledge progressed with the discovery of pulmonary circulation. The comprehension of the purpose of breathing progressed by steps thanks to Boyle and Mayow among others, and culminated with the contribution of Priestley and the discovery of oxygen by Lavoisier. Only then was breathing recognized as fulfilling the purpose of respiration, or gas exchange. A century later, a controversy emerged concerning the active or passive transfer of oxygen from alveoli to the blood. August and Marie Krogh settled the dispute, showing that passive diffusion was sufficient to meet the oxygen needs.

  18. Minimizing Shortness of Breath (United States)

    ... is also placed on proper use of the abdominal muscles to better control episodes of shortness of breath, ... Treatment & Programs Health Insights Doctors & Departments Research & Science Education & Training Make a Donation Make an Appointment Contact ...

  19. Breathing of heliospheric structures triggered by the solar-cycle activity

    Directory of Open Access Journals (Sweden)

    K. Scherer

    Full Text Available Solar wind ram pressure variations occuring within the solar activity cycle are communicated to the outer heliosphere as complicated time-variabilities, but repeating its typical form with the activity period of about 11 years. At outer heliospheric regions, the main surviving solar cycle feature is a periodic variation of the solar wind dynamical pressure or momentum flow, as clearly recognized by observations of the VOYAGER-1/2 space probes. This long-periodic variation of the solar wind dynamical pressure is modeled here through application of appropriately time-dependent inner boundary conditions within our multifluid code to describe the solar wind – interstellar medium interaction. As we can show, it takes several solar cycles until the heliospheric structures adapt to an average location about which they carry out a periodic breathing, however, lagged in phase with respect to the solar cycle. The dynamically active heliosphere behaves differently from a static heliosphere and especially shows a historic hysteresis in the sense that the shock structures move out to larger distances than explained by the average ram pressure. Obviously, additional energies are pumped into the heliosheath by means of density and pressure waves which are excited. These waves travel outwards through the interface from the termination shock towards the bow shock. Depending on longitude, the heliospheric sheath region memorizes 2–3 (upwind and up to 6–7 (downwind preceding solar activity cycles, i.e. the cycle-induced waves need corresponding travel times for the passage over the heliosheath. Within our multifluid code we also adequately describe the solar cycle variations in the energy distributions of anomalous and galactic cosmic rays, respectively. According to these results the distribution of these high energetic species cannot be correctly described on the basis of the actually prevailing solar wind conditions.

    Key words. Interplanetary

  20. Influence of forward leaning and incentive spirometry on inspired volumes and inspiratory electromyographic activity during breathing exercises in healthy subjects. (United States)

    Santos, Thalita Vilaboim; Ruas, Gualberto; Sande de Souza, Luciane Aparecida Pascucci; Volpe, Marcia Souza


    Breathing exercises (BE), incentive spirometry and positioning are considered treatment modalities to achieve lung re-expansion. This study evaluated the influence of incentive spirometry and forward leaning on inspired tidal volumes (V(T)) and electromyographic activity of inspiratory muscles during BE. Four modalities of exercises were investigated: deep breathing, spirometry using both flow and volume-oriented devices, and volume-oriented spirometry after modified verbal instruction. Twelve healthy subjects aged 22.7 ± 2.1 years were studied. Surface electromyography activity of diaphragm, external intercostals, sternocleidomastoid and scalenes was recorded. Comparisons among the three types of exercises, without considering spirometry after modified instruction, showed that electromyographic activity and V(T) were lower during volume-oriented spirometry (p = 0.000, p = 0.054, respectively). Forward leaning resulted in a lower V(T) when compared to upright sitting (p = 0.000), but electromyographic activity was not different (p = 0.606). Inspired V(T) and electromyographic activity were higher during volume-oriented spirometry performed after modified instruction when compared with the flow-oriented device (p = 0.027, p = 0.052, respectively). In conclusion BE using volume-oriented spirometry before modified instruction resulted in a lower work of breathing as a result of a lower V(T) and was not a consequence of the device type used. Forward leaning might not be assumed by healthy subjects during situations of augmented respiratory demand.

  1. Study on the feasibility of intensity-modulated treatments with breath control; Estudio sobre la viabilidad de tratamientos de intensidad modulada con control respiratorio

    Energy Technology Data Exchange (ETDEWEB)

    Zucca Aparicio, D.; Perez Moreno, J. M.; Fernandez Leton, P.; Garcia Ruiz-Zorrrilla, J.; Minambres Moro, A.


    The present work is to study the feasibility of IMRT treatments, both static and dynamic, with breath control offered by BrainLAB gating system and to quantify how the shadows of the measured dose profiles in case of respiratory motion are distorted for the case of NO movement.

  2. Control of cardiorespiratory function in response to hypoxia in an air-breathing fish, the African sharptooth catfish, Clarias gariepinus. (United States)

    Belão, T C; Zeraik, V M; Florindo, L H; Kalinin, A L; Leite, C A C; Rantin, F T


    We evaluated the role of the first pair of gill arches in the control of cardiorespiratory responses to normoxia and hypoxia in the air-breathing catfish, Clarias gariepinus. An intact group (IG) and an experimental group (EG, bilateral excision of first gill arch) were submitted to graded hypoxia, with and without access to air. The first pair of gill arches ablations reduced respiratory surface area and removed innervation by cranial nerve IX. In graded hypoxia without access to air, both groups displayed bradycardia and increased ventilatory stroke volume (VT), and the IG showed a significant increase in breathing frequency (fR). The EG exhibited very high fR in normoxia that did not increase further in hypoxia, this was linked to reduced O2 extraction from the ventilatory current (EO2) and a significantly higher critical O2 tension (PcO2) than the IG. In hypoxia with access to air, only the IG showed increased air-breathing, indicating that the first pair of gill arches excision severely attenuated air-breathing responses. Both groups exhibited bradycardia before and tachycardia after air-breaths. The fH and gill ventilation amplitude (VAMP) in the EG were overall higher than the IG. External and internal NaCN injections revealed that O2 chemoreceptors mediating ventilatory hypoxic responses (fR and VT) are internally oriented. The NaCN injections indicated that fR responses were mediated by receptors predominantly in the first pair of gill arches but VT responses by receptors on all gill arches. Receptors eliciting cardiac responses were both internally and externally oriented and distributed on all gill arches or extra-branchially. Air-breathing responses were predominantly mediated by receptors in the first pair of gill arches. In conclusion, the role of the first pair of gill arches is related to: (a) an elevated EO2 providing an adequate O2 uptake to maintain the aerobic metabolism during normoxia; (b) a significant bradycardia and increased fAB elicited

  3. Double-blind, placebo-controlled trial on the effect of piracetam on breath-holding spells. (United States)

    Sawires, Happy; Botrous, Osama


    Breath-holding spells (BHS) are apparently frightening events occurring in otherwise healthy children.The aim of this study was to evaluate the efficacy of piracetam in the treatment of breath-holding spells. Forty patients with BHS (who were classified into two groups)were involved in a double-blinded placebo-controlled prospective study. Piracetam was given to group A while group B received placebo. Patients were followed monthly for a total period of 4 months. The numbers of attacks/month before and monthly after treatment were documented, and the overall number of attacks/month after treatment was calculated in both groups. The median number of attacks/month before treatment in the two groups was 5.5 and 5,respectively, while after the first month of treatment, it was 2 and 5, respectively. The median overall number of attacks/month after treatment in both groups was 1 and 5, respectively.There was a significant decline of number of attacks after piracetam treatment compared to placebo (p valuepiracetam throughout the study period. In conclusion, piracetam is a safe and effective drug for the treatment of breath-holding spells in children.

  4. Habituation to experimentally induced electrical pain during voluntary-breathing controlled electrical stimulation (BreEStim.

    Directory of Open Access Journals (Sweden)

    Shengai Li

    Full Text Available OBJECTIVE: Painful peripheral electrical stimulation to acupuncture points was found to cause sensitization if delivered randomly (EStim, but induced habituation if triggered by voluntary breathing (BreEStim. The objective was to systematically compare the effectiveness of BreEStim and EStim and to investigate the possible mechanisms mediating the habituation effect of BreEStim. METHODS: Eleven pain-free, healthy subjects (6 males, 5 females participated in the study. Each subject received the BreEStim and EStim treatments in a random order at least three days apart. Both treatments consisted of 120 painful but tolerable stimuli to the ulnar nerve at the elbow on the dominant arm. BreEStim was triggered by voluntary breathing while EStim was delivered randomly. Electrical sensation threshold (EST and electrical pain threshold (EPT were measured from the thenar and hypothenar eminences on both hands at pre-intervention and 10-minutes post-intervention. RESULTS: There was no difference in the pre-intervention baseline measurement of EST and EPT between BreEStim and EStim. BreEStim increased EPT in all tested sites on both hands, while EStim increased EPT in the dominant hypothenar eminence distal to the stimulating site and had no effect on EPT in other sites. There was no difference in the intensity of electrical stimulation between EStim and BreEStim. CONCLUSION: Our findings support the important role human voluntary breathing plays in the systemic habituation effect of BreEStim to peripheral painful electrical stimulation.

  5. Swimming in air-breathing fishes. (United States)

    Lefevre, S; Domenici, P; McKenzie, D J


    Fishes with bimodal respiration differ in the extent of their reliance on air breathing to support aerobic metabolism, which is reflected in their lifestyles and ecologies. Many freshwater species undertake seasonal and reproductive migrations that presumably involve sustained aerobic exercise. In the six species studied to date, aerobic exercise in swim flumes stimulated air-breathing behaviour, and there is evidence that surfacing frequency and oxygen uptake from air show an exponential increase with increasing swimming speed. In some species, this was associated with an increase in the proportion of aerobic metabolism met by aerial respiration, while in others the proportion remained relatively constant. The ecological significance of anaerobic swimming activities, such as sprinting and fast-start manoeuvres during predator-prey interactions, has been little studied in air-breathing fishes. Some species practise air breathing during recovery itself, while others prefer to increase aquatic respiration, possibly to promote branchial ion exchange to restore acid-base balance, and to remain quiescent and avoid being visible to predators. Overall, the diversity of air-breathing fishes is reflected in their swimming physiology as well, and further research is needed to increase the understanding of the differences and the mechanisms through which air breathing is controlled and used during exercise.

  6. Evaluation of the Electromagnetic Power Absorption in Humans Exposed to Plane Waves: The Effect of Breathing Activity

    Directory of Open Access Journals (Sweden)

    Marta Cavagnaro


    Full Text Available The safety aspects of the exposure of people to uniform plane waves in the frequency range from 900 MHz to 5 GHz are analyzed. Starting from a human body model available in the literature, representing a man in resting state, two new anatomical models are considered, representing different phases of the respiratory activity: tidal breath and deep breath. These models have been used to evaluate the whole body Specific Absorption Rate (SAR and the 10-g averaged and 1-g averaged SAR. The analysis is performed using a parallel implementation of the finite difference time domain method. A uniform plane wave, with vertical polarization, is used as an incident field since this is the canonical exposure situation used in safety guidelines. Results show that if the incident electromagnetic field is compliant with the reference levels promulgated by the International Commission on Non-Ionizing Radiation Protection and by IEEE, the computed SAR values are lower than the corresponding basic restrictions, as expected. On the other side, when the Federal Communications Commission reference levels are considered, 1-g SAR values exceeding the basic restrictions for exposure at 4 GHz and above are obtained. Furthermore, results show that the whole body SAR values increase passing from the resting state model to the deep breath model, for all the considered frequencies.

  7. Parent misperception of control in childhood/adolescent asthma: the Room to Breathe survey. (United States)

    Carroll, W D; Wildhaber, J; Brand, P L P


    The aim of our study was to determine how often asthma control is achieved in children and adolescents, and how asthma affects parents' and children's daily lives. Interviews, including the childhood asthma control test (C-ACT), were conducted with 1,284 parents of asthmatic children (aged 4-15 yrs), as well as with the children themselves (aged 8-15 yrs; n=943), in Canada, Greece, Hungary, the Netherlands, South Africa and the UK. Parents reported mild asthma attacks at least weekly in 11% of children, and serious attacks (requiring oral corticosteroids or hospitalisation) at least annually in 35%. Although 73% of parents described their child's asthma as mild or intermittent, 40% of children/adolescents had C-ACT scores ≤ 19, indicating inadequate control, and only 14.7% achieved complete Global Initiative for Asthma (GINA)-defined control and just 9.2% achieved Scottish Intercollegiate Guidelines Network (SIGN)/British Thoracic Society (BTS)-defined control. Guideline-defined asthma control was significantly less common than well-controlled asthma using the C-ACT (pAsthma restricted the child's activities in 39% of families and caused lifestyle changes in 70%. Complete asthma control is uncommon in children worldwide. Guideline-defined control measures appear to be more stringent than those defined by C-ACT or families. Overall, parents underestimate their child's asthma severity and overestimate asthma control. This is a major potential barrier to successful asthma treatment in children.

  8. Breathe In, Breathe Out

    Centers for Disease Control (CDC) Podcasts


    This podcast promotes healthy lifestyle messages through original music.  Created: 11/1/2007 by National Diabetes Education Program (NDEP), a joint program of the Centers for Disease Control and Prevention and the National Institutes of Health.   Date Released: 11/30/2007.

  9. 主动呼吸控制结合三维适形放疗非小细胞肺癌的初步研究%Primary application of active breathing control system in conformal radiotherapy for patients with non-small cell lung cancer

    Institute of Scientific and Technical Information of China (English)

    王健; 曾昭冲; 吴铮; 朱姜轶; 章娴; 钱杨; 鞠忠建; 白春学


    目的 探讨医科达公司主动呼吸控制(ABC)系统结合三维适形放疗技术治疗非小细胞肺癌(NSCLC)可行性.方法 29例Ⅱ~Ⅳ期未能手术的NSCLC患者分别在自由呼吸(FB)状态和ABC控制下行CT扫描,并在两个重建图像序列中按同样条件分别设计FB和ABC后的三维适形放疗计划.选择屏气触发方式为吸气后屏气,触发阈值设定为呼吸曲线峰值的80%,每次最长屏气时间为25 s.上叶病灶计划靶体积(PTV)为临床靶体积(CTV)外放0.6 cm;中下叶病灶PTV为CTV外放1.0 cm.采用3~5个野进行共面适形治疗.通过剂量体积直方图评价两个计划的大体肿瘤体积(GTV)、CTV、PTV、双肺体积(V_(lung))、双肺V_(20).和平均肺剂量(MLD).近期疗效按世界卫生组织肿瘤疗后客观效果评分.正常组织急性反应按美国国家癌症研究所CTC3.0标准评价.结果 除1例患者因经济原因中断治疗,其他患者均顺利完成治疗.使用ABe技术后GTV、CTV、PTV均较FB技术有一定缩小[36.35 cm~3:31.40 cm~3(t=9.70,P<0.001)、82.33 cm~3:70.83 cm~3(t=8.19,P<0.001)、230.73 cm~3:197.59 cm~3(t=5.72,P<0.001)],双肺V_(20)、MLD均低于FB技术[21.66%:18.76%(t=11.16,P<0.001)、1329.07 Gy:1143.14 Gy(t=13.24,P<0.001)].总有效率为64%(18例).急性放射性食管炎发生率1、2级分别为68%(19例)、18%(5例);急性放射性肺损伤发生率1、2级分别为82%(23例)、7%(2例);骨髓抑制发生率1、2、3级分别为57%(16例)、25%(7例)、14%(4例);急性心脏损伤1、2级分别为86%(24例)、14%(4例).结论 ABC的临床应用可行,靶区定位更为精确,可减少正常肺组织照射剂量,从而减少放射副反应的发生率.%Objective To evaluate the feasibility of active breathing control (ABC) in conformal radiotherapy (CRT) for patients with non-small cell lung cancer (NSCLC). Methods From Feb 2005 to Mar 2008, 29 patients with inoperable NSCLC (stage Ⅱ-Ⅳ) were evaluated. For each patient, two series of CT

  10. Improved inhaled air quality at reduced ventilation rate by control of airflow interaction at the breathing zone with lobed jets

    DEFF Research Database (Denmark)

    Bolashikov, Zhecho Dimitrov; Melikov, Arsen Krikor; Spilak, Michal


    Inhaled air quality at a reduced supply of clean air was studied by controlling the airflow interaction at the breathing zone of a person using lobed jets as part of personalized ventilation (PV). Experiments were performed in a full-scale test room at 23°C (73.4°F) with a breathing thermal manikin......) equivalent diameter. The nozzles were positioned frontally at the face within the boundary layer and centered to the mouth. The enhancement of inhaled air quality by changing the initial velocity (0.2-0.6 m/s, 0.66-1.97 fps) and the distance from the mouth (0.02-0.06 m, 0.07-0.20 ft) was studied. The control...... over the interaction between the inserted jets and the free convection flow was efficient. Over 80% clean PV air was measured in inhalation. The worst performing nozzle was the four-leafed clover: its best performance yielded 23% clean air inhalation, at the shortest distance and the highest velocity...

  11. Breathing simulator of workers for respirator performance test. (United States)

    Yuasa, Hisashi; Kumita, Mikio; Honda, Takeshi; Kimura, Kazushi; Nozaki, Kosuke; Emi, Hitoshi; Otani, Yoshio


    Breathing machines are widely used to evaluate respirator performance but they are capable of generating only limited air flow patterns, such as, sine, triangular and square waves. In order to evaluate the respirator performance in practical use, it is desirable to test the respirator using the actual breathing patterns of wearers. However, it has been a difficult task for a breathing machine to generate such complicated flow patterns, since the human respiratory volume changes depending on the human activities and workload. In this study, we have developed an electromechanical breathing simulator and a respiration sampling device to record and reproduce worker's respiration. It is capable of generating various flow patterns by inputting breathing pattern signals recorded by a computer, as well as the fixed air flow patterns. The device is equipped with a self-control program to compensate the difference in inhalation and exhalation volume and the measurement errors on the breathing flow rate. The system was successfully applied to record the breathing patterns of workers engaging in welding and reproduced the breathing patterns.

  12. Validation of low activity {sup 14}C-urea breath test in diagnosis of ``Helicobacter pylori``in humans

    Energy Technology Data Exchange (ETDEWEB)

    Bielanski, W.; Konturek, S.J.; Dobrzanka, M.J.; Plonka, M.; Sito, E.; Stachura, J. [Uniwersytet Jagiellonski, Cracow (Poland); Hoffman, S.R.; Marshall, B.J. [Tri-Med Specialtis, Charlottenville, VA (United States)


    Etiologic role for ``Helicobacter pylori`` (HP) seems to be well established in gastric pathology. The high urease activity of HP can be used to detect this bacterium by non-invasive urea breath tests (UBT). We validated the low activity version of the test in which 37 kBq {sup 14}C-urea is given orally in capsule. With the cut off value {>=} 1.66 Bq (100 DPM) as positive, UBT results correlated highly significant with combined results for invasive methods, i.e. CLO-test + Histology score. The reproducibility of the test was 100%. The results obtained for the breath test performed locally were almost identical with that read at remote laboratory. The data found for fasting and fed states of subjects agreed in 87%. When {sup 14}C-urea was confined in the mouth of both HP positive and HP negative patients UBT showed the presence of urease activity in the mouth cavity. (author). 21 refs, 2 figs, 1 tab.

  13. Breathing-controlled electrical stimulation could modify the affective component of neuropathic pain after amputation: a case report

    Directory of Open Access Journals (Sweden)

    Melton DH


    Full Text Available Sheng Li1,2, Danielle H Melton1, Jeffrey C Berliner11Department of Physical Medicine and Rehabilitation, University of Texas Medical School – Houston, Houston, TX; 2UTHealth Motor Recovery Laboratory, Institute for Rehabilitation and Research, Memorial Hermann Hospital, Houston, TX, USAAbstract: In this case, a 31-year-old male suffered phantom neuropathic pain for more than 3 years after an above-the-knee amputation. His shooting phantom pain disappeared after the first session of breathing-controlled electrical stimulation, and reappeared or was triggered 28 days after an experimental error during which he received sustained electrical stimulation. In other words, painful shooting stimuli may not have been “cured” but forgotten and retriggered by a fearful event due to the experimental error. Therefore, this accidental finding provides a unique opportunity to understand sensory and affective components of neuropathic pain, and a novel intervention could modify the affective component of it.Keywords: neuropathic pain, amputation, electrical stimulation, voluntary breathing

  14. Transfer function analysis of the autonomic response to respiratory activity during random interval breathing (United States)

    Chen, M. H.; Berger, R. D.; Saul, J. P.; Stevenson, K.; Cohen, R. J.


    We report a new method for the noninvasive characterization of the frequency response of the autonomic nervous system (ANS) in mediating fluctuations in heart rate (HR). The approach entails computation of the transfer function magnitude and phase between instantaneous lung volume and HR. Broad band fluctuations in lung volume were initiated when subjects breathed on cue to a sequence of beeps spaced randomly in time. We studied 10 subjects in both supine and standing positions. The transfer function, averaged among all the subjects, showed systematic differences between the two postures, reflecting the differing frequency responses of the sympathetic and parasympathetic divisions of the ANS.

  15. Coordination of tongue activity during swallowing in mouth-breathing children. (United States)

    Knösel, Michael; Klein, Sabine; Bleckmann, Annalen; Engelke, Wilfried


    Habitual mouth breathing is often accompanied by habitual anterior tongue thrust, instead of a lip closure, in order to create the anterior seal necessary for the initiation of physiological deglutition. We tested the null hypothesis of no significant influence of oral maneuver and the use of oral screens on tongue coordination and position during deglutition in 29 subjects (age = 6-16; mean = 9.69 years; 13/16 female/male) with habitual open-mouth posture using intraoral polysensography. The target parameters for swallowing were swallowing-associated nasal airflow interruption (NAI) and coordination of tongue-palate contact during NAI. Conventional myofunctional maneuvers could be facilitated and made more efficient, in terms of increasing the numbers of favorable early tongue-palate contacts typical of somatic swallowing, if accompanied by the application of an oral screen. Habitual open-mouth breathing does not necessarily coincide with distinctively pronounced proportions of late tongue-palate contact.

  16. The Breathe Easier through Weight Loss Lifestyle (BE WELL Intervention: A randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Buist A


    Full Text Available Abstract Background Obesity and asthma have reached epidemic proportions in the US. Their concurrent rise over the last 30 years suggests that they may be connected. Numerous observational studies support a temporally-correct, dose-response relationship between body mass index (BMI and incident asthma. Weight loss, either induced by surgery or caloric restriction, has been reported to improve asthma symptoms and lung function. Due to methodological shortcomings of previous studies, however, well-controlled trials are needed to investigate the efficacy of weight loss strategies to improve asthma control in obese individuals. Methods/Design BE WELL is a 2-arm parallel randomized clinical trial (RCT of the efficacy of an evidence-based, comprehensive, behavioral weight loss intervention, focusing on diet, physical activity, and behavioral therapy, as adjunct therapy to usual care in the management of asthma in obese adults. Trial participants (n = 324 are patients aged 18 to 70 years who have suboptimally controlled, persistent asthma, BMI between 30.0 and 44.9 kg/m2, and who do not have serious comorbidities (e.g., diabetes, heart disease, stroke. The 12-month weight loss intervention to be studied is based on the principles of the highly successful Diabetes Prevention Program lifestyle intervention. Intervention participants will attend 13 weekly group sessions over a four-month period, followed by two monthly individual sessions, and will then receive individualized counseling primarily by phone, at least bi-monthly, for the remainder of the intervention. Follow-up assessment will occur at six and 12 months. The primary outcome variable is the overall score on the Juniper Asthma Control Questionnaire measured at 12 months. Secondary outcomes include lung function, asthma-specific and general quality of life, asthma medication use, asthma-related and total health care utilization. Potential mediators (e.g., weight loss and change in physical

  17. Conformation-controlled sorption properties and breathing of the aliphatic Al-MOF [Al(OH)(CDC)]. (United States)

    Niekiel, Felicitas; Lannoeye, Jeroen; Reinsch, Helge; Munn, Alexis S; Heerwig, Andreas; Zizak, Ivo; Kaskel, Stefan; Walton, Richard I; de Vos, Dirk; Llewellyn, Philip; Lieb, Alexandra; Maurin, Guillaume; Stock, Norbert


    The Al-MOF CAU-13 ([Al(OH)(trans-CDC)]; trans-H2CDC = trans-1,4-cyclohexanedicarboxylic acid) is structurally related to the MIL-53 compounds that are well-known for their "breathing" behavior, i.e., the framework flexibility upon external stimuli such as the presence of adsorbate molecules. The adsorption properties of CAU-13 were investigated in detail. The sorption isotherms of N2, H2, CH4, CO, CO2, and water were recorded, and the adsorption enthalpies for the gases were determined by microcalorimetry. The structural changes upon adsorption of CO2 were followed with in situ synchrotron powder X-ray diffraction (PXRD). The patterns were analyzed by parametric unit cell refinement, and the preferential arrangement of the CO2 molecules was modeled by density functional theory calculations. The adsorption and separation of mixtures of o-, m-, and p-xylene from mesitylene showed a preferred adsorption of o-xylene. The structures of o/m/p-xylene-loaded CAU-13 were determined from PXRD data. The adsorption of xylene isomers induces a larger pore opening than that in the thermal activation of CAU-13. In the crystal structure of the activated sample CAU-13(empty pore), half of the linkers adopt the a,a confirmation and the other half the e,e conformation, and the presence of a,a-CDC(2-) ions hampers the structural flexibility of CAU-13. However, after the adsorption of xylene, all linkers are present in the e,e conformation, allowing for a wider pore opening by this new type of "breathing".

  18. The non-invasive 13C-methionine breath test detects hepatic mitochondrial dysfunction as a marker of disease activity in non-alcoholic steatohepatitis

    Directory of Open Access Journals (Sweden)

    Banasch M


    Full Text Available Abstract Introduction Mitochondrial dysfunction plays a central role in the general pathogenesis of non-alcoholic fatty liver disease (NAFLD, increasing the risk of developing steatosis and subsequent hepatocellular inflammation. We aimed to assess hepatic mitochondrial function by a non-invasive 13C-methionine breath test (MeBT in patients with histologically proven NAFLD. Methods 118 NAFLD-patients and 18 healthy controls were examined by MeBT. Liver biopsy specimens were evaluated according to the NASH scoring system. Results Higher grades of NASH activity and fibrosis were independently associated with a significant decrease in cumulative 13C-exhalation (expressed as cPDR(%. cPDR1.5h was markedly declined in patients with NASH and NASH cirrhosis compared to patients with simple steatosis or borderline diagnosis (cPDR1.5h: 3.24 ± 1.12% and 1.32 ± 0.94% vs. 6.36 ± 0.56% and 4.80 ± 0.88% respectively; p 13C-exhalation further declined in the presence of advanced fibrosis which was correlated with NASH activity (r = 0.36. The area under the ROC curve (AUROC for NASH diagnosis was estimated to be 0.87 in the total cohort and 0.83 in patients with no or mild fibrosis (F0-1. Conclusion The 13C-methionine breath test indicates mitochondrial dysfunction in non-alcoholic fatty liver disease and predicts higher stages of disease activity. It may, therefore, be a valuable diagnostic addition for longitudinal monitoring of hepatic (mitochondrial function in non-alcoholic fatty liver disease.

  19. Non-fragile switching tracking control for a flexible air-breathing hypersonic vehicle based on polytopic LPV model

    Institute of Scientific and Technical Information of China (English)

    Huang Yiqing; Sun Changyin; Qian Chengshan; Wang Li


    This article proposes a linear parameter varying (LPV) switching tracking control scheme for a flexible air-breathing hypersonic vehicle (FAHV).First,a polytopic LPV model is constructed to represent the complex nonlinear longitudinal model of the FAHV by using Jacobian linearization and tensor-product (T-P) model transformation approach.Second,for less conservative controller design purpose,the flight envelope is divided into four sub-regions and a non-fragile LPV controller is designed for each parameter sub-region.These non-fragile LPV controllers are then switched in order to guarantee the closed-loop FAHV system to be asymptotically stable and satisfy a specified performance criterion.The desired non-fragile LPV switching controller is found by solving a convex constraint problem which can be efficiently solved using available linear matrix inequality (LMI) techniques,and robust stability analysis of the closed-loop FAHV system is verified based on multiple Lypapunov functions (MLFs).Finally,numerical simulations have demonstrated the effectiveness of the proposed approach.

  20. Acid sensing ion channel 1 in lateral hypothalamus contributes to breathing control.

    Directory of Open Access Journals (Sweden)

    Nana Song

    Full Text Available Acid-sensing ion channels (ASICs are present in neurons and may contribute to chemoreception. Among six subunits of ASICs, ASIC1 is mainly expressed in the central nervous system. Recently, multiple sites in the brain including the lateral hypothalamus (LH have been found to be sensitive to extracellular acidification. Since LH contains orexin neurons and innervates the medulla respiratory center, we hypothesize that ASIC1 is expressed on the orexin neuron and contributes to acid-induced increase in respiratory drive. To test this hypothesis, we used double immunofluorescence to determine whether ASIC1 is expressed on orexin neurons in the LH, and assessed integrated phrenic nerve discharge (iPND in intact rats in response to acidification of the LH. We found that ASIC1 was co-localized with orexinA in the LH. Microinjection of acidified artificial cerebrospinal fluid increased the amplitude of iPND by 70% (pH 7.4 v.s. pH 6.5:1.05±0.12 v.s. 1.70±0.10, n = 6, P<0.001 and increased the respiratory drive (peak amplitude of iPND/inspiratory time, PA/Ti by 40% (1.10±0.23 v.s. 1.50±0.38, P<0.05. This stimulatory effect was abolished by blocking ASIC1 with a nonselective inhibitor (amiloride 10 mM, a selective inhibitor (PcTX1, 10 nM or by damaging orexin neurons in the LH. Current results support our hypothesis that the orexin neuron in the LH can exert an excitation on respiration via ASIC1 during local acidosis. Since central acidification is involved in breathing dysfunction in a variety of pulmonary diseases, understanding its underlying mechanism may improve patient management.

  1. Tracking Control for an Overactuated Hypersonic Air-Breathing Vehicle with Steady State Constraints (PREPRINT) (United States)


    choice of a steady state control is completely independent from the choice of a stabilizing control law. This separation is key for the methods we will...develop for steady state optimization in later sections. Combining the steady state with the stabilizing control , we can express the control law as u...for stabilizing control and optimization methods for steady state control, both unconstrained and constrained, we were able to produce promising results

  2. Comparison of active cycle of breathing and high-frequency oscillation jacket in children with cystic fibrosis. (United States)

    Phillips, Gillian E; Pike, Sarah E; Jaffé, Adam; Bush, Andrew


    High-frequency chest compressions (HFCC) have been suggested as an alternative to conventional chest physiotherapy to aid sputum clearance in patients with cystic fibrosis (CF). We aimed to compare the active cycle of breathing techniques (ACBT) with the Hayek Oscillator Cuirass, performing HFCC on secretion clearance in children with CF during an exacerbation. Ten children (7 males; median age, 14 years; range, 9-16) received either two supervised sessions using HFCC or two self-treatment ACBT sessions in random order on successive days. Baseline pulmonary function was similar prior to treatments. Sputum weight increased significantly with ACBT compared with HFCC during treatment (5.2 g vs. 1.1 g, P HFCC. Compared with ACBT, HFCC by Hayek Cuirass is not an effective airway clearance treatment modality for children with CF during an infective exacerbation.

  3. Comparison of exhaled breath condensate pH using two commercially available devices in healthy controls, asthma and COPD patients

    Directory of Open Access Journals (Sweden)

    Vogelmeier Claus


    Full Text Available Abstract Background Analysis of exhaled breath condensate (EBC is a non-invasive method for studying the acidity (pH of airway secretions in patients with inflammatory lung diseases. Aim To assess the reproducibility of EBC pH for two commercially available devices (portable RTube and non-portable ECoScreen in healthy controls, patients with asthma or COPD, and subjects suffering from an acute cold with lower-airway symptoms. In addition, we assessed the repeatability in healthy controls. Methods EBC was collected from 40 subjects (n = 10 in each of the above groups using RTube and ECoScreen. EBC was collected from controls on two separate occasions within 5 days. pH in EBC was assessed after degasification with argon for 20 min. Results In controls, pH-measurements in EBC collected by RTube or ECoScreen showed no significant difference between devices (p = 0.754 or between days (repeatability coefficient RTube: 0.47; ECoScreen: 0.42 of collection. A comparison between EBC pH collected by the two devices in asthma, COPD and cold patients also showed good reproducibility. No differences in pH values were observed between controls (mean pH 8.27; RTube and patients with COPD (pH 7.97 or asthma (pH 8.20, but lower values were found using both devices in patients with a cold (pH 7.56; RTube, p Conclusion We conclude that pH measurements in EBC collected by RTube and ECoScreen are repeatable and reproducible in healthy controls, and are reproducible and comparable in healthy controls, COPD and asthma patients, and subjects with a common cold.

  4. Comparison of Diaphragmatic Breathing Exercise, Volume and Flow Incentive Spirometry, on Diaphragm Excursion and Pulmonary Function in Patients Undergoing Laparoscopic Surgery: A Randomized Controlled Trial

    Directory of Open Access Journals (Sweden)

    Gopala Krishna Alaparthi


    Full Text Available Objective. To evaluate the effects of diaphragmatic breathing exercises and flow and volume-oriented incentive spirometry on pulmonary function and diaphragm excursion in patients undergoing laparoscopic abdominal surgery. Methodology. We selected 260 patients posted for laparoscopic abdominal surgery and they were block randomization as follows: 65 patients performed diaphragmatic breathing exercises, 65 patients performed flow incentive spirometry, 65 patients performed volume incentive spirometry, and 65 patients participated as a control group. All of them underwent evaluation of pulmonary function with measurement of Forced Vital Capacity (FVC, Forced Expiratory Volume in the first second (FEV1, Peak Expiratory Flow Rate (PEFR, and diaphragm excursion measurement by ultrasonography before the operation and on the first and second postoperative days. With the level of significance set at p<0.05. Results. Pulmonary function and diaphragm excursion showed a significant decrease on the first postoperative day in all four groups (p<0.001 but was evident more in the control group than in the experimental groups. On the second postoperative day pulmonary function (Forced Vital Capacity and diaphragm excursion were found to be better preserved in volume incentive spirometry and diaphragmatic breathing exercise group than in the flow incentive spirometry group and the control group. Pulmonary function (Forced Vital Capacity and diaphragm excursion showed statistically significant differences between volume incentive spirometry and diaphragmatic breathing exercise group (p<0.05 as compared to that flow incentive spirometry group and the control group. Conclusion. Volume incentive spirometry and diaphragmatic breathing exercise can be recommended as an intervention for all patients pre- and postoperatively, over flow-oriented incentive spirometry for the generation and sustenance of pulmonary function and diaphragm excursion in the management of

  5. Air breath control radiotherapy in severe insufficiency respiratory patients with N.S.C.L.: application for deformable registration method in thoracic radiotherapy; Radiotherapie avec blocage respiratoire pour les grands insuffisants respiratoires atteints d'un carcinome pulmonaire non a petites cellules (Protocole RESPI 2000): application a la modelisation des deformations d'organes par recalage deformable

    Energy Technology Data Exchange (ETDEWEB)

    Sarrut, D.; Pommier, P.; Carrie, C. [Centre Leon-Berard, Dept. de Radiotherapie, CREATIS, Unite CNRS 5515, Inserm 630, 69 - Lyon (France); Perol, D. [Centre Leon-Berard, Dept. de Biostatistique, 69 - Lyon (France)


    Purpose. Using deformable registration methods from a phase two clinical study of air breath control during radiotherapy in patients suffering from severe respiratory insufficiency and non-small cell lung carcinoma. Patients and methods, Between April 2002 and November 2005, 22 patients with severe respiratory insufficiency were treated with curative intent by conformal therapy combined with active breathing control. Results. After a mean of follow-up of 22 months, the local control rate is 28% and the method is feasible despite the severe respiratory insufficiency. However the overall survival is still poor due to metastatic widespread. For the second part of the study, the clinical protocol was also used for two studies using deformable registration methods. In the first study, a deformable registration method has been developed in order to register several breath-hold 3D CT of the same patient acquired at several days of interval. It allowed quantifying the inter-fraction breath-hold reproducibility by analysing the resulting displacement field. For 6 patients, the breath-hold was effective, while for 2 patients, motion greater than 10 mm were detected. The second study aimed to simulate 4D images from 3D breath-hold images. Developing an ad-hoc methodology based on the interpolation of 3D dense deformation fields performed it. The approach has been validated with expert selected landmarks, with accuracy lower than 3 mm. Conclusion. ABC is feasible, even in case of severe insufficiency respiratory syndrome but metastatic widespread disease is still a major challenge even with an acceptable local control rate without serious side effects: regarding the deformable registration method. Such artificial 4D images could allow decreasing the dose need to acquire a full 4D image, to simulate irregular breathing pattern and to be used for 4D dosimetry planning. (author)

  6. Active noise control primer

    CERN Document Server

    Snyder, Scott D


    Active noise control - the reduction of noise by generating an acoustic signal that actively interferes with the noise - has become an active area of basic research and engineering applications. The aim of this book is to present all of the basic knowledge one needs for assessing how useful active noise control will be for a given problem and then to provide some guidance for designing, setting up, and tuning an active noise-control system. Written for students who have no prior knowledge of acoustics, signal processing, or noise control but who do have a reasonable grasp of basic physics and mathematics, the book is short and descriptive. It leaves for more advanced texts or research monographs all mathematical details and proofs concerning vibrations, signal processing and the like. The book can thus be used in independent study, in a classroom with laboratories, or in conjunction with a kit for experiment or demonstration. Topics covered include: basic acoustics; human perception and sound; sound intensity...

  7. Modification of electrical pain threshold by voluntary breathing-controlled electrical stimulation (BreEStim in healthy subjects.

    Directory of Open Access Journals (Sweden)

    Shengai Li

    Full Text Available BACKGROUND: Pain has a distinct sensory and affective (i.e., unpleasantness component. BreEStim, during which electrical stimulation is delivered during voluntary breathing, has been shown to selectively reduce the affective component of post-amputation phantom pain. The objective was to examine whether BreEStim increases pain threshold such that subjects could have improved tolerance of sensation of painful stimuli. METHODS: Eleven pain-free healthy subjects (7 males, 4 females participated in the study. All subjects received BreEStim (100 stimuli and conventional electrical stimulation (EStim, 100 stimuli to two acupuncture points (Neiguan and Weiguan of the dominant hand in a random order. The two different treatments were provided at least three days apart. Painful, but tolerable electrical stimuli were delivered randomly during EStim, but were triggered by effortful inhalation during BreEStim. Measurements of tactile sensation threshold, electrical sensation and electrical pain thresholds, thermal (cold sensation, warm sensation, cold pain and heat pain thresholds were recorded from the thenar eminence of both hands. These measurements were taken pre-intervention and 10-min post-intervention. RESULTS: There was no difference in the pre-intervention baseline measurement of all thresholds between BreEStim and EStim. The electrical pain threshold significantly increased after BreEStim (27.5±6.7% for the dominant hand and 28.5±10.8% for the non-dominant hand, respectively. The electrical pain threshold significantly decreased after EStim (9.1±2.8% for the dominant hand and 10.2±4.6% for the non-dominant hand, respectively (F[1, 10] = 30.992, p = .00024. There was no statistically significant change in other thresholds after BreEStim and EStim. The intensity of electrical stimuli was progressively increased, but no difference was found between BreEStim and EStim. CONCLUSION: Voluntary breathing controlled electrical stimulation

  8. Parent misperception of control in childhood/adolescent asthma : the Room to Breathe survey

    NARCIS (Netherlands)

    Carroll, W. D.; Wildhaber, J.; Brand, P. L. P.


    The aim of our study was to determine how often asthma control is achieved in children and adolescents, and how asthma affects parents' and children's daily lives. Interviews, including the childhood asthma control test (C-ACT), were conducted with 1,284 parents of asthmatic children (aged 4-15 yrs)

  9. Breath alcohol test (United States)

    Alcohol test - breath ... There are various brands of breath alcohol tests. Each one uses a different method to test the level of alcohol in the breath. The machine may be electronic or manual. One ...

  10. Rapid shallow breathing (United States)

    Tachypnea; Breathing - rapid and shallow; Fast shallow breathing; Respiratory rate - rapid and shallow ... Shallow, rapid breathing has many possible medical causes, including: Asthma Blood clot in an artery in the lung Choking Chronic obstructive ...

  11. Breath-holding and its breakpoint. (United States)

    Parkes, M J


    This article reviews the basic properties of breath-holding in humans and the possible causes of the breath at breakpoint. The simplest objective measure of breath-holding is its duration, but even this is highly variable. Breath-holding is a voluntary act, but normal subjects appear unable to breath-hold to unconsciousness. A powerful involuntary mechanism normally overrides voluntary breath-holding and causes the breath that defines the breakpoint. The occurrence of the breakpoint breath does not appear to be caused solely by a mechanism involving lung or chest shrinkage, partial pressures of blood gases or the carotid arterial chemoreceptors. This is despite the well-known properties of breath-hold duration being prolonged by large lung inflations, hyperoxia and hypocapnia and being shortened by the converse manoeuvres and by increased metabolic rate. Breath-holding has, however, two much less well-known but important properties. First, the central respiratory rhythm appears to continue throughout breath-holding. Humans cannot therefore stop their central respiratory rhythm voluntarily. Instead, they merely suppress expression of their central respiratory rhythm and voluntarily 'hold' the chest at a chosen volume, possibly assisted by some tonic diaphragm activity. Second, breath-hold duration is prolonged by bilateral paralysis of the phrenic or vagus nerves. Possibly the contribution to the breakpoint from stimulation of diaphragm muscle chemoreceptors is greater than has previously been considered. At present there is no simple explanation for the breakpoint that encompasses all these properties.

  12. Tracking control of a class of non-linear systems with applications to cruise control of air-breathing hypersonic vehicles (United States)

    Sun, Hongfei; Yang, Zhiling; Meng, Bin


    A new tracking-control method for general non-linear systems is proposed. A virtual controller and some command references are introduced to asymptotically stabilise the system of the tracking error dynamics. Then, the actual controller and command references are derived by solving a system of linear algebraic equations. Compared with other tracking-control methods in the literature, the tracking-controller design in this paper is simple because it needs only to solve a system of linear algebraic equations. The boundedness of the tracking controller and command references is guaranteed by the solvability of the terminal value problem (TVP) of an ordinary differential equation. For non-linear systems with minimum-phase properties, the TVP is automatically solvable. A numerical example shows that the tracking-control method is still available for some systems with non-minimum-phase properties. To enhance the robustness of the tracking controller, a non-linear disturbance observer (NDO) is introduced to estimate the disturbance. The combination of the tracking controller and the NDO is applied to the tracking control of an air-breathing hypersonic vehicle.

  13. 42 CFR 84.88 - Breathing bag test. (United States)


    ... 42 Public Health 1 2010-10-01 2010-10-01 false Breathing bag test. 84.88 Section 84.88 Public... RESEARCH AND RELATED ACTIVITIES APPROVAL OF RESPIRATORY PROTECTIVE DEVICES Self-Contained Breathing Apparatus § 84.88 Breathing bag test. (a) Breathing bags will be tested in an air atmosphere saturated...

  14. Air Breathing Propulsion Controls and Diagnostics Research at NASA Glenn Under NASA Aeronautics Research Mission Programs (United States)

    Garg, Sanjay


    The Intelligent Control and Autonomy Branch (ICA) at NASA (National Aeronautics and Space Administration) Glenn Research Center (GRC) in Cleveland, Ohio, is leading and participating in various projects in partnership with other organizations within GRC and across NASA, the U.S. aerospace industry, and academia to develop advanced controls and health management technologies that will help meet the goals of the NASA Aeronautics Research Mission Directorate (ARMD) Programs. These efforts are primarily under the various projects under the Advanced Air Vehicles Program (AAVP), Airspace Operations and Safety Program (AOSP) and Transformative Aeronautics Concepts Program (TAC). The ICA Branch is focused on advancing the state-of-the-art of aero-engine control and diagnostics technologies to help improve aviation safety, increase efficiency, and enable operation with reduced emissions. This paper describes the various ICA research efforts under the NASA Aeronautics Research Mission Programs with a summary of motivation, background, technical approach, and recent accomplishments for each of the research tasks.

  15. Evaluation of some significant issues affecting trajectory and control management for air-breathing hypersonic vehicles (United States)

    Hattis, Philip D.; Malchow, Harvey L.


    Horizontal takeoff airbreathing-propulsion launch vehicles require near-optimal guidance and control which takes into account performance sensitivities to atmospheric characteristics while satisfying physically-derived operational constraints. A generic trajectory/control analysis tool that deepens insight into these considerations has been applied to two versions of a winged-cone vehicle model. Information that is critical to the design and trajectory of these vehicles is derived, and several unusual characteristics of the airbreathing propulsion model are shown to have potentially substantial effects on vehicle dynamics.

  16. Optical Breath Gas Extravehicular Activity Sensor for the Advanced Portable Life Support System (United States)

    Wood, William R.; Casias, Miguel E.; Pilgrim, Jeffrey S.; Chullen, Cinda; Campbell, Colin


    The function of the infrared gas transducer used during extravehicular activity (EVA) in the current space suit is to measure and report the concentration of carbon dioxide (CO2) in the ventilation loop. The next generation portable life support system (PLSS) requires highly accurate CO2 sensing technology with performance beyond that presently in use on the International Space Station extravehicular mobility unit (EMU). Further, that accuracy needs to be provided over the full operating pressure range of the suit (3 to 25 psia). Accommodation within space suits demands that optical sensors meet stringent size, weight, and power requirements. A laser diode (LD) sensor based on infrared absorption spectroscopy is being developed for this purpose by Vista Photonics, Inc. Version 1.0 prototype devices were delivered to NASA Johnson Space Center (JSC) in September 2011. The prototypes were upgraded with more sophisticated communications and faster response times to version 2.0 and delivered to JSC in July 2012. The sensors incorporate a laser diode based CO2 channel that also includes an incidental water vapor (humidity) measurement. The prototypes are controlled digitally with an field-programmable gate array microcontroller architecture. Based on the results of the iterative instrument development, further prototype development and testing of instruments were performed leveraging the lessons learned where feasible. The present development extends and upgrades the earlier hardware for the advanced PLSS 2.5 prototypes for testing at JSC. The prototypes provide significantly enhanced accuracy for water vapor measurement and eliminate wavelength drift affecting the earlier versions. Various improvements to the electronics and gas sampling are currently being advanced including the companion development of engineering development units that will ultimately be capable of radiation tolerance. The combination of low power electronics with the performance of a long wavelength

  17. The clinical efficacy of Colgate Total Plus Whitening Toothpaste containing a special grade of silica and Colgate Total Toothpaste for controlling breath odor twelve hours after toothbrushing: a single-use clinical study. (United States)

    Sharma, Naresh C; Galustians, H Jack; Qaqish, Jimmy; Galustians, Ana; Petrone, Margaret E; Rustogi, Kedar N; Zhang, Yun Po; DeVizio, William; Volpe, Anthony R


    The objective of this double-blind clinical study, conducted in harmony with American Dental Association guidelines, was to compare a new dentifrice formulation variant of Colgate Total Toothpaste containing a special grade of silica (Colgate Total Plus Whitening Toothpaste) to the commercially available, ADA-Accepted and clinically proven Colgate Total Toothpaste for controlling breath odor twelve hours after brushing the teeth. Breath odor was evaluated by a panel of three examiners using a nine-point hedonic scale. Following a baseline evaluation of breath odor, prospective study subjects who scored above the threshold value for unpleasant breath odor were stratified by score and randomized into two treatment groups. Subjects were provided with a soft-bristled toothbrush, and brushed their teeth thoroughly in their regular and customary manner with their assigned dentifrice. Subjects refrained from dental hygiene, breath mints or mounthrinses for the next twelve hours, after which they were again evaluated for breath odor. Eighty-three (83) adult male and female subjects from the Mississauga, Ontario, Canada area participated in the study. At twelve hours after brushing their teeth, subjects in both dentifrice treatment groups presented mean breath odor scores which were statistically significantly lower than the mean scores observed at baseline. Importantly, there was no statistical difference between the two dentifrices of the mean twelve-hour breath odor scores. The mean twelve-hour breath scores for the Colgate Total Plus Whitening Toothpaste group and the Colgate Total Toothpaste group were 4.89 and 4.67, respectively, which are within the range of values corresponding to pleasant breath odor. Thus, the results of this double-blind clinical study, conducted according to a protocol which had been approved by the Council on Scientific Affairs of the American Dental Association, support the conclusion that Colgate Total Plus Whitening Toothpaste and Colgate

  18. Exhaled breath condensate nitric oxide end products and pH in controlled asthma

    Directory of Open Access Journals (Sweden)

    Ahmed Elhefny


    Conclusion: EBC-NOx is significantly higher and EBC-pH is significantly lower in asthmatic patients than in control subjects. Asthmatics receiving ICS have a lower EBC-NOx level than those not. EBC-NOx and EBC-pH were significantly correlated and both of them showed significant correlations with spirometric parameters of airway obstruction.

  19. Breath Figures Formation


    Guadarrama-Cetina, J.; González-Viñas, W


    We present experimental observations of Breath Figures (BF) which are formed by the dew of water when it condenses on a cold surface. The experiments were done in specific conditions and configurations of temperature, surfaces and mixes in controlled concentration of miscibles and immiscibles substances like the salt saturated solution, alcohol and silicon oil (C_6H_18O_2Si). The hydrophobic surfaces used on those observations are thin glasses coated with ITO (Indium Tin Oxide), 3M ECG-1700 w...

  20. Slow breathing and hypoxic challenge: cardiorespiratory consequences and their central neural substrates. (United States)

    Critchley, Hugo D; Nicotra, Alessia; Chiesa, Patrizia A; Nagai, Yoko; Gray, Marcus A; Minati, Ludovico; Bernardi, Luciano


    Controlled slow breathing (at 6/min, a rate frequently adopted during yoga practice) can benefit cardiovascular function, including responses to hypoxia. We tested the neural substrates of cardiorespiratory control in humans during volitional controlled breathing and hypoxic challenge using functional magnetic resonance imaging (fMRI). Twenty healthy volunteers were scanned during paced (slow and normal rate) breathing and during spontaneous breathing of normoxic and hypoxic (13% inspired O2) air. Cardiovascular and respiratory measures were acquired concurrently, including beat-to-beat blood pressure from a subset of participants (N = 7). Slow breathing was associated with increased tidal ventilatory volume. Induced hypoxia raised heart rate and suppressed heart rate variability. Within the brain, slow breathing activated dorsal pons, periaqueductal grey matter, cerebellum, hypothalamus, thalamus and lateral and anterior insular cortices. Blocks of hypoxia activated mid pons, bilateral amygdalae, anterior insular and occipitotemporal cortices. Interaction between slow breathing and hypoxia was expressed in ventral striatal and frontal polar activity. Across conditions, within brainstem, dorsal medullary and pontine activity correlated with tidal volume and inversely with heart rate. Activity in rostroventral medulla correlated with beat-to-beat blood pressure and heart rate variability. Widespread insula and striatal activity tracked decreases in heart rate, while subregions of insular cortex correlated with momentary increases in tidal volume. Our findings define slow breathing effects on central and cardiovascular responses to hypoxic challenge. They highlight the recruitment of discrete brainstem nuclei to cardiorespiratory control, and the engagement of corticostriatal circuitry in support of physiological responses that accompany breathing regulation during hypoxic challenge.



    BELAL S. A. S.; Nazarenko, E.; Radchenko, A.; Kulik, A.; MARTYNENKO A.; Yabluchansky, N.


    On 15 healthy volunteers aged from 18 to 22 years the effect of ivabradine on the quality of biofeedback in the loop of paced breathing under the control of heart rate variability parameters were estimated. It was found that ivabradine contributes to an earlier onset and more significant optimization of regulatory systems in systematic sessions of biofeedback that allows to expand the indications for its clinical use.

  2. Diaphragmatic Breathing Reduces Exercise-Induced Oxidative Stress

    Directory of Open Access Journals (Sweden)

    Daniele Martarelli


    Full Text Available Diaphragmatic breathing is relaxing and therapeutic, reduces stress, and is a fundamental procedure of Pranayama Yoga, Zen, transcendental meditation and other meditation practices. Analysis of oxidative stress levels in people who meditate indicated that meditation correlates with lower oxidative stress levels, lower cortisol levels and higher melatonin levels. It is known that cortisol inhibits enzymes responsible for the antioxidant activity of cells and that melatonin is a strong antioxidant; therefore, in this study, we investigated the effects of diaphragmatic breathing on exercise-induced oxidative stress and the putative role of cortisol and melatonin hormones in this stress pathway. We monitored 16 athletes during an exhaustive training session. After the exercise, athletes were divided in two equivalent groups of eight subjects. Subjects of the studied group spent 1 h relaxing performing diaphragmatic breathing and concentrating on their breath in a quiet place. The other eight subjects, representing the control group, spent the same time sitting in an equivalent quite place. Results demonstrate that relaxation induced by diaphragmatic breathing increases the antioxidant defense status in athletes after exhaustive exercise. These effects correlate with the concomitant decrease in cortisol and the increase in melatonin. The consequence is a lower level of oxidative stress, which suggests that an appropriate diaphragmatic breathing could protect athletes from long-term adverse effects of free radicals.

  3. The efficiency of active cycle of breathing techniques regarding the improvement the quality of life in cystic fibrosis patients

    Directory of Open Access Journals (Sweden)

    Bogdan Almăjan-Guţă


    Full Text Available Background: Physiotherapy is well known as one of the most important part of CF patient’s management. The right choice ofappropriate therapy schema will improve the life’s quality of the patients. The purpose of the study was to prove the efficiencyof Active cycle of breathing techniques at children with cystic fibrosis. The study was performed between September 2006-september 2007 and the lot of study consisted of 20 children (11 girls and 9 boys with an age range between 6 and 18 years(average 14,8 years from the records of the Cystic Fibrosis National Centre Timisoara. The results showed an improvement inall measured values: general well-being, coughing, physical signs, X-ray signs and CT, bacteriological exam, nutritional status,functional respiratory tests. The statistical briefing of data shows the fact that there are significant statistical difference (p<0,05, before and after treatment in all ventilator index. The conclusion of this study was that the chosen technique (ACTBproved to be very efficient, in improving of respiratory symptoms and ventilator parameters

  4. Comparison of exhaled breath condensate pH using two commercially available devices in healthy controls, asthma and COPD patients

    NARCIS (Netherlands)

    Koczulla, R.; Dragonieri, S.; Schot, R.; Bals, R.; Gauw, S.A.; Vogelmeier, C.; Rabe, K.F.; Sterk, P.J.; Hiemstra, P.S.


    ABSTRACT: BACKGROUND: Analysis of exhaled breath condensate (EBC) is a non-invasive method for studying the acidity (pH) of airway secretions in patients with inflammatory lung diseases. Aim: To assess the reproducibility of EBC pH for two commercially available devices (portable RTube and non-porta

  5. Effect of device-guided breathing exercises on blood pressure in patients with hypertension : A randomized controlled trial

    NARCIS (Netherlands)

    Altena, Mariette R.; Kleefstra, Nanne; Logtenberg, Susan J.; Groenier, Klaas H.; Houweling, Sebastiaan T.; Bilo, Henk J.


    Objective. Hypertension is a chronic disorder with a high prevalence worldwide. Despite considerable efforts, it is sometimes hard to reach treatment goals for blood pressure (BP) with classical treatment options. Reducing breathing frequency has been advocated as a method to reduce BP. Methods. A r

  6. Fractionated breath condensate sampling: H2O2 concentrations of the alveolar fraction may be related to asthma control in children

    Directory of Open Access Journals (Sweden)

    Trischler Jordis


    Full Text Available Abstract Background Asthma is a chronic inflammatory disease of the airways but recent studies have shown that alveoli are also subject to pathophysiological changes. This study was undertaken to compare hydrogen peroxide (H2O2 concentrations in different parts of the lung using a new technique of fractioned breath condensate sampling. Methods In 52 children (9-17 years, 32 asthmatic patients, 20 controls measurements of exhaled nitric oxide (FENO, lung function, H2O2 in exhaled breath condensate (EBC and the asthma control test (ACT were performed. Exhaled breath condensate was collected in two different fractions, representing mainly either the airways or the alveoli. H2O2 was analysed in the airway and alveolar fractions and compared to clinical parameters. Results The exhaled H2O2 concentration was significantly higher in the airway fraction than in the alveolar fraction comparing each single pair (p = 0.003, 0.032 and 0.040 for the whole study group, the asthmatic group and the control group, respectively. Asthma control, measured by the asthma control test (ACT, correlated significantly with the H2O2 concentrations in the alveolar fraction (r = 0.606, p = 0.004 but not with those in the airway fraction in the group of children above 12 years. FENO values and lung function parameters did not correlate to the H2O2 concentrations of each fraction. Conclusion The new technique of fractionated H2O2 measurement may differentiate H2O2 concentrations in different parts of the lung in asthmatic and control children. H2O2 concentrations of the alveolar fraction may be related to the asthma control test in children.

  7. Effects of high-frequency yoga breathing called kapalabhati compared with breath awareness on the degree of optical illusion perceived. (United States)

    Telles, Shirley; Maharana, Kanchan; Balrana, Budhi; Balkrishna, Acharya


    Prior research has shown that methods of meditation, breath control, and different kinds of yoga breathing affect attention and visual perception, including decreasing the size of certain optical illusions. Evaluating relationships sheds light on the perceptual and cognitive changes induced by yoga and related methods, and the locus of the effects. In the present study, the degree of optical illusion was assessed using Müller-Lyer stimuli before and immediately after two different kinds of practice, a high frequency yoga breathing called kapalabhati, and breath awareness. A nonyoga, control session tested for practice effects. Thirty participants (with group M age = 26.9 yr., SD = 5.7) practiced the two techniques for 18 min. on two separate days. The control group had 15 nonyoga practitioners assessed before and after 18 min. in which they did not perform any specific activity but were seated and relaxed. After both kapalabhati and breath awareness there was a significant decrease in the degree of optical illusion. The possibility that this was due to a practice or repetition effect was ruled out when 15 nonyoga practitioners showed no change in the degree of illusion when retested after 18 min. The changes were interpreted as due to changes in perception related to the way the stimuli were judged.

  8. Active Flow Control (United States)



    This paper considers the two-dimensional problem of a plane vortex sheet disturbed by an impulsive line source. A previous incorrect treatment of this problem is examined in detail. Instabilities of the vortex sheet are triggered by the source and grow exponentially in space and time. The Green function is constructed for the problem and it is shown that a point source properly positioned and delayed will induce a field that cancels the unstable growing modes. The resulting displacement of the vortex sheet is expressed in simple terms. The instabilities are checked by the anti-source which combines with the field of the primary source into a vortex sheet response which decays with time at large time. This paper is a contribution to the study of active control of shear layer instabilities, the main contribution being to clear up a previous paper with peculiar results that are, in fact, wrong.

  9. Ecological sounds affect breath duration more than artificial sounds. (United States)

    Murgia, Mauro; Santoro, Ilaria; Tamburini, Giorgia; Prpic, Valter; Sors, Fabrizio; Galmonte, Alessandra; Agostini, Tiziano


    Previous research has demonstrated that auditory rhythms affect both movement and physiological functions. We hypothesized that the ecological sounds of human breathing can affect breathing more than artificial sounds of breathing, varying in tones for inspiration and expiration. To address this question, we monitored the breath duration of participants exposed to three conditions: (a) ecological sounds of breathing, (b) artificial sounds of breathing having equal temporal features as the ecological sounds, (c) no sounds (control). We found that participants' breath duration variability was reduced in the ecological sound condition, more than in the artificial sound condition. We suggest that ecological sounds captured the timing of breathing better than artificial sounds, guiding as a consequence participants' breathing. We interpreted our results according to the Theory of Event Coding, providing further support to its validity, and suggesting its possible extension in the domain of physiological functions which are both consciously and unconsciously controlled.

  10. Evaluation of CYP2D6 enzyme activity using a Dextromethorphan Breath Test in Women Receiving Adjuvant Tamoxifen (United States)

    Safgren, Stephanie L.; Suman, Vera J.; Kosel, Matthew L.; Gilbert, Judith A; Buhrow, Sarah A.; Black, John L.; Northfelt, Donald W.; Modak, Anil S.; Rosen, David; Ingle, James N.; Ames, Matthew M.; Reid, Joel M.; Goetz, Matthew P.


    Background In tamoxifen-treated patients, breast cancer recurrence differs according to CYP2D6 genotype and endoxifen steady state concentrations (Endx Css). The 13Cdextromethorphan breath test (DM-BT), labeled with 13C at the O-CH3 moiety, measures CYP2D6 enzyme activity. We sought to examine the ability of the DM-BT to identify known CYP2D6 genotypic poor metabolizers and examine the correlation between DMBT and Endx Css. Methods DM-BT and tamoxifen pharmacokinetics were obtained at baseline (b), 3 month (3m) and 6 months (6m) following tamoxifen initiation. Potent CYP2D6 inhibitors were prohibited. The correlation between bDM-BT with CYP2D6 genotype and Endx Css was determined. The association between bDM-BT (where values ≤0.9 is an indicator of poor in vivo CYP2D6 metabolism) and Endx Css (using values ≤ 11.2 known to be associated with poorer recurrence free survival) was explored. Results 91 patients were enrolled and 77 were eligible. CYP2D6 genotype was positively correlated with b, 3m and 6m DMBT (r ranging from 0.457-0. 60 p 11.2 nM. Conclusions In patients not taking potent CYP2D6 inhibitors, DM-BT was associated with CYP2D6 genotype and 3m and 6 m Endx Css but did not provide better discrimination of Endx Css compared to CYP2D6 genotype alone. Further studies are needed to identify additional factors which alter Endx Css. PMID:25714002

  11. What Causes Bad Breath? (United States)

    ... A Week of Healthy Breakfasts Shyness What Causes Bad Breath? KidsHealth > For Teens > What Causes Bad Breath? A A A en español ¿Qué es lo que provoca el mal aliento? Bad breath, or halitosis , can be a major problem, ...

  12. Application of LaserBreath-001 for breath acetone measurement in subjects with diabetes mellitus (United States)

    Wang, Zhennan; Sun, Meixiu; Chen, Zhuying; Zhao, Xiaomeng; Li, Yingxin; Wang, Chuji


    Breath acetone is a promising biomarker of diabetes mellitus. With an integrated standalone, on-site cavity ringdown breath acetone analyzer, LaserBreath-001, we tested breath samples from 23 type 1 diabetic (T1D) patients, 312 type 2 diabetic (T2D) patients, 52 healthy subjects. In the cross-sectional studies, the obtained breath acetone concentrations were higher in the diabetic subjects compared with those in the control group. No correlation between breath acetone and simultaneous BG was observed in the T1D, T2D, and healthy subjects. A moderate positive correlation between the mean individual breath acetone concentrations and the mean individual BG levels was observed in the 20 T1D patients without ketoacidosis. In a longitudinal study, the breath acetone concentrations in a T1D patient with ketoacidosis decreased significantly and remained stable during the 5-day hospitalization. The results from a relatively large number of subjects tested indicate that an elevated mean breath acetone concentration exists in diabetic patients in general. Although many physiological parameters affect breath acetone concentrations, fast (diabetic screening and management under a specifically controlled condition.

  13. Efficacy of a mandibular advancement appliance on sleep-disordered breathing in children: a study protocol of a crossover randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Ghassan Idris


    Full Text Available Background: Sleep-Disordered Breathing (SDB varies from habitual snoring to partial or complete obstruction of the upper airway and can be found in up to 10% of children. SDB can significantly affect children’s wellbeing, as it can cause growth disorders, educational and behavioral problems, and even life-threatening conditions, such as cardiorespiratory failure. Adenotonsillectomy represents the primary treatment for pediatric SDB where adeno-tonsillar hypertrophy is indicated. For those with craniofacial anomalies, or for whom adenotonsillectomy or other treatment modalities have failed, or surgery is contra-indicated, mandibular advancement splints (MAS may represent a viable treatment option. Whilst the efficacy of these appliances has been consistently demonstrated in adults, there is little information about their effectiveness in children.Aims: To determine the efficacy of mandibular advancement appliances for the management of SDB and related health problems in children. Methods/design: The study will be designed as a single-blind crossover randomized controlled trial with administration of both an ‘Active MAS’ (Twin-block and a ‘Sham MAS’. Eligible participants will be children aged 8 to 12 years whose parents report they snore ≥ 3 nights per week. Sixteen children will enter the full study after confirming other inclusion criteria, particularly Skeletal class I or class II confirmed by lateral cephalometric radiograph. Each child will be randomly assigned to either a treatment sequence starting with the Active or the Sham MAS. Participants will wear the appliances for three weeks separated by a two-week washout period. For each participant, home-based polysomnographic data will be collected four times; once before and once after each treatment period. The Apnea Hypopnea Index (AHI will represent the main outcome variable. Secondary outcomes will include, snoring frequency, masseter muscle activity, sleep symptoms, quality

  14. Active control of convection

    Energy Technology Data Exchange (ETDEWEB)

    Bau, H.H. [Univ. of Pennsylvania, Philadelphia, PA (United States)


    Using stability theory, numerical simulations, and in some instances experiments, it is demonstrated that the critical Rayleigh number for the bifurcation (1) from the no-motion (conduction) state to the motion state and (2) from time-independent convection to time-dependent, oscillatory convection in the thermal convection loop and Rayleigh-Benard problems can be significantly increased or decreased. This is accomplished through the use of a feedback controller effectuating small perturbations in the boundary data. The controller consists of sensors which detect deviations in the fluid`s temperature from the motionless, conductive values and then direct actuators to respond to these deviations in such a way as to suppress the naturally occurring flow instabilities. Actuators which modify the boundary`s temperature/heat flux are considered. The feedback controller can also be used to control flow patterns and generate complex dynamic behavior at relatively low Rayleigh numbers.

  15. Active Combustion Control Valve Project (United States)

    National Aeronautics and Space Administration — Over the past decade, research into active combustion control has yielded impressive results in suppressing thermoacoustic instabilities and widening the...

  16. Active Combustion Control Valve Project (United States)

    National Aeronautics and Space Administration — Over the past decade, research into active combustion control has yielded impressive results in suppressing thermoacoustic instabilities and widening the operational...

  17. An Ultrasonic Contactless Sensor for Breathing Monitoring

    Directory of Open Access Journals (Sweden)

    Philippe Arlotto


    Full Text Available The monitoring of human breathing activity during a long period has multiple fundamental applications in medicine. In breathing sleep disorders such as apnea, the diagnosis is based on events during which the person stops breathing for several periods during sleep. In polysomnography, the standard for sleep disordered breathing analysis, chest movement and airflow are used to monitor the respiratory activity. However, this method has serious drawbacks. Indeed, as the subject should sleep overnight in a laboratory and because of sensors being in direct contact with him, artifacts modifying sleep quality are often observed. This work investigates an analysis of the viability of an ultrasonic device to quantify the breathing activity, without contact and without any perception by the subject. Based on a low power ultrasonic active source and transducer, the device measures the frequency shift produced by the velocity difference between the exhaled air flow and the ambient environment, i.e., the Doppler effect. After acquisition and digitization, a specific signal processing is applied to separate the effects of breath from those due to subject movements from the Doppler signal. The distance between the source and the sensor, about 50 cm, and the use of ultrasound frequency well above audible frequencies, 40 kHz, allow monitoring the breathing activity without any perception by the subject, and therefore without any modification of the sleep quality which is very important for sleep disorders diagnostic applications. This work is patented (patent pending 2013-7-31 number FR.13/57569.

  18. An ultrasonic contactless sensor for breathing monitoring. (United States)

    Arlotto, Philippe; Grimaldi, Michel; Naeck, Roomila; Ginoux, Jean-Marc


    The monitoring of human breathing activity during a long period has multiple fundamental applications in medicine. In breathing sleep disorders such as apnea, the diagnosis is based on events during which the person stops breathing for several periods during sleep. In polysomnography, the standard for sleep disordered breathing analysis, chest movement and airflow are used to monitor the respiratory activity. However, this method has serious drawbacks. Indeed, as the subject should sleep overnight in a laboratory and because of sensors being in direct contact with him, artifacts modifying sleep quality are often observed. This work investigates an analysis of the viability of an ultrasonic device to quantify the breathing activity, without contact and without any perception by the subject. Based on a low power ultrasonic active source and transducer, the device measures the frequency shift produced by the velocity difference between the exhaled air flow and the ambient environment, i.e., the Doppler effect. After acquisition and digitization, a specific signal processing is applied to separate the effects of breath from those due to subject movements from the Doppler signal. The distance between the source and the sensor, about 50 cm, and the use of ultrasound frequency well above audible frequencies, 40 kHz, allow monitoring the breathing activity without any perception by the subject, and therefore without any modification of the sleep quality which is very important for sleep disorders diagnostic applications. This work is patented (patent pending 2013-7-31 number FR.13/57569).

  19. The small breathing amplitude at the upper lobes favours the attraction of polymorphonuclear neutrophils to Mycobacterium tuberculosis lesions and helps to understand the evolution towards active disease in an individual-based model

    Directory of Open Access Journals (Sweden)

    Pere-Joan eCardona


    Full Text Available Infection with Mycobacterium tuberculosis (Mtb can induce two kinds of lesions, namely proliferative and exudative. The former are based on the presence of macrophages with controlled induction of intragranulomatous necrosis, and are even able to stop its physical progression, thus avoiding the induction of active tuberculosis (TB. In contrast, the most significant characteristic of exudative lesions is their massive infiltration with polymorphonuclear neutrophils (PMNs, which favour enlargement of the lesions and extracellular growth of the bacilli. We have built an individual-based model (IBM (known as TBPATCH using the NetLogo interface to better understand the progression from Mtb infection to TB. We have tested four main factors previously identified as being able to favour the infiltration of Mtb-infected lesions with PMNs, namely the tolerability of infected macrophages to the bacillary load; the capacity to modulate the Th17 response; the breathing amplitude (large or small in the lower and upper lobes respectively, which influences bacillary drainage at the alveoli; and the encapsulation of Mtb-infected lesions by the interlobular septae that structure the pulmonary parenchyma into secondary lobes. Overall, although all the factors analysed play some role, the small breathing amplitude is the major factor determining whether Mtb-infected lesions become exudative, and thus induce TB, thereby helping to understand why this usually takes place in the upper lobes. This information will be very useful for the design of future prophylactic and therapeutic approaches against TB.

  20. The cerebral cost of breathing: an FMRI case-study in congenital central hypoventilation syndrome.

    Directory of Open Access Journals (Sweden)

    Mike Sharman

    Full Text Available Certain motor activities--like walking or breathing--present the interesting property of proceeding either automatically or under voluntary control. In the case of breathing, brainstem structures located in the medulla are in charge of the automatic mode, whereas cortico-subcortical brain networks--including various frontal lobe areas--subtend the voluntary mode. We speculated that the involvement of cortical activity during voluntary breathing could impact both on the "resting state" pattern of cortical-subcortical connectivity, and on the recruitment of executive functions mediated by the frontal lobe. In order to test this prediction we explored a patient suffering from central congenital hypoventilation syndrome (CCHS, a very rare developmental condition secondary to brainstem dysfunction. Typically, CCHS patients demonstrate efficient cortically-controlled breathing while awake, but require mechanically-assisted ventilation during sleep to overcome the inability of brainstem structures to mediate automatic breathing. We used simultaneous EEG-fMRI recordings to compare patterns of brain activity between these two types of ventilation during wakefulness. As compared with spontaneous breathing (SB, mechanical ventilation (MV restored the default mode network (DMN associated with self-consciousness, mind-wandering, creativity and introspection in healthy subjects. SB on the other hand resulted in a specific increase of functional connectivity between brainstem and frontal lobe. Behaviorally, the patient was more efficient in cognitive tasks requiring executive control during MV than during SB, in agreement with her subjective reports in everyday life. Taken together our results provide insight into the cognitive and neural costs of spontaneous breathing in one CCHS patient, and suggest that MV during waking periods may free up frontal lobe resources, and make them available for cognitive recruitment. More generally, this study reveals how the

  1. Active Control of Suspension Bridges

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle

    In this paper some recent research on active control of very long suspension bridges, is presented. The presentation is based on research work at Aalborg University, Denmark. The active control system is based on movable flaps attached to the bridge girder. Wind load on bridges with or without...... flaps attached to the girder is briefly presented. A simple active control system is discussed. Results from wind tunnel experiments with a bridge section show that flaps can be used effectively to control bridge girder vibrations. Flutter conditions for suspension bridges with and without flaps...

  2. Loss of Breathing Modulation of Heart Rate Variability in Patients with Recent and Long Standing Diabetes Mellitus Type II (United States)

    Estañol, Bruno; Fossion, Ruben; Toledo-Roy, Juan C.; Callejas-Rojas, José A.; Gien-López, José A.; Delgado-García, Guillermo R.; Frank, Alejandro


    Healthy subjects under rhythmic breathing have heart interbeat intervals with a respiratory band in the frequency domain that can be an index of vagal activity. Diabetes Mellitus Type II (DM) affects the autonomic nervous system of patients, thus it can be expected changes on the vagal activity. Here, the influence of DM on the breathing modulation of the heart rate is evaluated by analyzing in the frequency domain heart interbeat interval (IBI) records obtained from 30 recently diagnosed, 15 long standing DM patients, and 30 control subjects during standardized clinical tests of controlled breathing at 0.1 Hz, supine rest and standing upright. Fourier spectral analysis of IBI records quantifies heart rate variability in different regions: low-frequencies (LF, 0.04–0.15 Hz), high-frequencies (HF, 0.15–0.4 Hz), and a controlled breathing peak (RP, centered around 0.1 Hz). Two new parameters are introduced: the frequency radius rf (square root of the sum of LF and HF squared) and β (power of RP divided by the sum of LF and HF). As diabetes evolves, the controlled breathing peak loses power and shifts to smaller frequencies, indicating that heart rate modulation is slower in diabetic patients than in controls. In contrast to the traditional parameters LF, HF and LF/HF, which do not show significant differences between the three populations in neither of the clinical tests, the new parameters rf and β, distinguish between control and diabetic subjects in the case of controlled breathing. Sympathetic activity that is driven by the baroreceptor reflex associated with the 0.1 Hz breathing modulations is affected in DM patients. Diabetes produces not only a rigid heartbeat with less autonomic induced variability (rf diminishes), but also alters the coupling between breathing and heart rate (reduced β), due to a progressive decline of vagal and sympathetic activity. PMID:27802329

  3. Automaticity or active control

    DEFF Research Database (Denmark)

    Tudoran, Ana Alina; Olsen, Svein Ottar

    aspects of the construct, such as routine, inertia, automaticity, or very little conscious deliberation. The data consist of 2962 consumers participating in a large European survey. The results show that habit strength significantly moderates the association between satisfaction and action loyalty, and......This study addresses the quasi-moderating role of habit strength in explaining action loyalty. A model of loyalty behaviour is proposed that extends the traditional satisfaction–intention–action loyalty network. Habit strength is conceptualised as a cognitive construct to refer to the psychological......, respectively, between intended loyalty and action loyalty. At high levels of habit strength, consumers are more likely to free up cognitive resources and incline the balance from controlled to routine and automatic-like responses....

  4. The relationship between body temperature, heart rate, breathing rate, and rate of oxygen consumption, in the tegu lizard (Tupinambis merianae) at various levels of activity. (United States)

    Piercy, Joanna; Rogers, Kip; Reichert, Michelle; Andrade, Denis V; Abe, Augusto S; Tattersall, Glenn J; Milsom, William K


    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 O2 supply and demand. In a first series of experiments, the rate of oxygen consumption (VO2), breathing frequency (fR), heart rate (fH), 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 fR, tidal volume (VT), the fraction of oxygen extracted from the lung per breath (FIO2-FEO2), fH, and the cardiac O2 pulse were quantified to determine the relative roles of each of these variables in accommodating changes in VO2. The increases in oxygen supply to meet temperature- and activity-induced increases in oxygen demand were produced almost exclusively by increases in fH and fR. Regression analysis showed that the effects of temperature and activity state on the relationships between fH, fR and VO2 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 fR and fH were maximized when the effects of changes in temperature, digestive state and activity were pooled. However, the best r(2) values obtained were 0.63 and 0.74 using fR and fH as predictors of metabolic rate, respectively.

  5. Temperatura do ar exalado, um novo biomarcador no controle da asma: um estudo piloto Exhaled breath temperature, a new biomarker in asthma control: a pilot study

    Directory of Open Access Journals (Sweden)

    Raul Emrich Melo


    Full Text Available OBJETIVO: Avaliar se a temperatura do ar exalado (TAE, medida por um método não invasivo, é efetiva no monitoramento de pacientes com asma não controlada. MÉTODOS: Estudo piloto com nove pacientes (sete mulheres e dois homens; média de idade: 39 anos com diagnóstico de asma por pelo menos um ano e sem uso de tratamento de manutenção por pelo menos três meses antes do início do estudo. Na primeira visita, os pacientes foram submetidos à espirometria e à medida da TAE. Todos os pacientes foram orientados a iniciar tratamento com budesonida/formoterol (200/6 µg inalatório a cada 12 h por seis semanas. Além disso, os pacientes com asma grave (VEF1 OBJECTIVE: To evaluate whether the exhaled breath temperature (EBT, measured by a noninvasive method, is an effective means of monitoring patients with uncontrolled asthma. METHODS: A pilot study comprising nine patients (seven women and two men; mean age: 39 years diagnosed with asthma at least one year prior to the beginning of the study and not having been under maintenance therapy for the last three months. In the first visit, the patients underwent spirometry and measurement of EBT. The patients were then instructed to use inhaled budesonide/formoterol (200/6 µg every 12 h for six weeks. In addition, the patients with severe asthma (FEV1 < 60% of predicted were instructed to use oral prednisolone (40 mg/day for five days. After six weeks, the patients underwent the same tests. RESULTS: All of the patients reported an improvement in the symptoms of asthma, as confirmed by a statistically significant increase in FEV1 from the first to the second visit (mean, 56.1% vs. 88.7% of predicted; p < 0.05. Five patients used oral prednisolone for the first five days of the treatment period. Six patients used additional doses of inhaled budesonide/formoterol (mean duration, 2.5 weeks. The EBT decreased significantly from the first to the second visit (mean EBT: 35.1ºC vs. 34.1ºC; p < 0

  6. Active control: Wind turbine model

    DEFF Research Database (Denmark)

    Bindner, H.


    . The models are all formulated as linear differential equations. The models are validated throughcomparisons with measurements performed on a Vestas WD 34 400 kW wind turbine. It is shown from a control point of view simple linear models can be used to describe the dynamic behavior of a pitch controlled wind......This report is a part of the reporting of the work done in the project 'Active Control of Wind Turbines'. This project aim is to develop a simulation model for design of control systems for turbines with pitch control and to use that model to designcontrollers. This report describes the model...... developed for controller design and analysis. Emphasis has been put on establishment of simple models describing the dynamic behavior of the wind turbine in adequate details for controller design. This hasbeen done with extensive use of measurements as the basis for selection of model complexity and model...

  7. Device-Guided Breathing as Treatment for Hypertension in Type 2 Diabetes Mellitus A Randomized, Double-blind, Sham-Controlled Trial

    NARCIS (Netherlands)

    Landman, Gijs W. D.; Drion, Iefke; van Hateren, J. J.; van Dijk, Peter R.; Logtenberg, Susan J. J.; Lambert, Jan; Groenier, Klaas H.; Bilo, Henk J. G.; Kleefstra, Nanne


    IMPORTANCE Biofeedback with device-guided lowering of breathing frequency could be an alternate nonpharmacologic treatment option for hypertension. Evidence from trials with high methodologic quality is lacking. OBJECTIVE To evaluate the effects of device-guided lowering of breathing frequency on bl

  8. Fast and Accurate Exhaled Breath Ammonia Measurement


    Solga, Steven F; Mudalel, Matthew L; Spacek, Lisa A.; Risby, Terence H.


    This exhaled breath ammonia method uses a fast and highly sensitive spectroscopic method known as quartz enhanced photoacoustic spectroscopy (QEPAS) that uses a quantum cascade based laser. The monitor is coupled to a sampler that measures mouth pressure and carbon dioxide. The system is temperature controlled and specifically designed to address the reactivity of this compound. The sampler provides immediate feedback to the subject and the technician on the quality of the breath effort. Toge...

  9. Demonstration of Active Combustion Control (United States)

    Lovett, Jeffrey A.; Teerlinck, Karen A.; Cohen, Jeffrey M.


    The primary objective of this effort was to demonstrate active control of combustion instabilities in a direct-injection gas turbine combustor that accurately simulates engine operating conditions and reproduces an engine-type instability. This report documents the second phase of a two-phase effort. The first phase involved the analysis of an instability observed in a developmental aeroengine and the design of a single-nozzle test rig to replicate that phenomenon. This was successfully completed in 2001 and is documented in the Phase I report. This second phase was directed toward demonstration of active control strategies to mitigate this instability and thereby demonstrate the viability of active control for aircraft engine combustors. This involved development of high-speed actuator technology, testing and analysis of how the actuation system was integrated with the combustion system, control algorithm development, and demonstration testing in the single-nozzle test rig. A 30 percent reduction in the amplitude of the high-frequency (570 Hz) instability was achieved using actuation systems and control algorithms developed within this effort. Even larger reductions were shown with a low-frequency (270 Hz) instability. This represents a unique achievement in the development and practical demonstration of active combustion control systems for gas turbine applications.

  10. Fractional active disturbance rejection control. (United States)

    Li, Dazi; Ding, Pan; Gao, Zhiqiang


    A fractional active disturbance rejection control (FADRC) scheme is proposed to improve the performance of commensurate linear fractional order systems (FOS) and the robust analysis shows that the controller is also applicable to incommensurate linear FOS control. In FADRC, the traditional extended states observer (ESO) is generalized to a fractional order extended states observer (FESO) by using the fractional calculus, and the tracking differentiator plus nonlinear state error feedback are replaced by a fractional proportional-derivative controller. To simplify controller tuning, the linear bandwidth-parameterization method has been adopted. The impacts of the observer bandwidth ωo and controller bandwidth ωc on system performance are then analyzed. Finally, the FADRC stability and frequency-domain characteristics for linear single-input single-output FOS are analyzed. Simulation results by FADRC and ADRC on typical FOS are compared to demonstrate the superiority and effectiveness of the proposed scheme.

  11. Fast-starting for a breath: Air breathing in Hoplosternum littorale

    DEFF Research Database (Denmark)

    Domenici, Paolo; Norin, Tommy; Bushnell, Peter G.

    by the fall of a prey item on the water surface, and in tapping motions of goldfish, a behaviour that was interpreted to be food-related. Little is known about C-starts being used outside the context of escaping or feeding. Here, we test the hypothesis that air-breathing fish may use C-starts when gulping air...... at the surface. Air breathing is a common behaviour in many fish species when exposed to hypoxia, although certain species perform air-breathing in normoxia to fill their swim bladders for buoyancy control and/or sound transduction. Hoplosternum littorale is an air-breathing freshwater catfish found in South......, with those of mechanically-triggered C-start escape responses. Our results show that these two behaviours overlap considerably in their kinematics (turning rates and distance covered), suggesting that air breathing in this species is performed using escapelike C-start motions. This demonstrates that C...

  12. Extended Active Disturbance Rejection Controller (United States)

    Gao, Zhiqiang (Inventor); Tian, Gang (Inventor)


    Multiple designs, systems, methods and processes for controlling a system or plant using an extended active disturbance rejection control (ADRC) based controller are presented. The extended ADRC controller accepts sensor information from the plant. The sensor information is used in conjunction with an extended state observer in combination with a predictor that estimates and predicts the current state of the plant and a co-joined estimate of the system disturbances and system dynamics. The extended state observer estimates and predictions are used in conjunction with a control law that generates an input to the system based in part on the extended state observer estimates and predictions as well as a desired trajectory for the plant to follow.

  13. An introduction to the psychophysiology of breathing. (United States)

    Ley, R


    Breathing can be viewed as an independent variable which affects emotion, cognition, and behavior as well as a dependent variable which reflects changes in emotion, cognition, and behavior. This bidirectional interaction is basic to an appreciation of the significance of breathing in terms of its relevance in research and application. The underlying premise of the present article is that since breathing is a behavior that is under voluntary as well as reflexive control, it can be modified according to the principles of both instrumental training (operant conditioning) and Pavlovian (classical) conditioning. The implications of this premise are relevant to theory, diagnosis, and treatment of stress and anxiety-related disorders (e.g., panic disorder, phobias, test anxiety, occupational strain, and related psychosomatic disorders), and to basic and applied research in the psychophysiology of breathing.

  14. Breathing exercises for adults with asthma. (United States)


    Asthma is a common long-term condition that remains poorly controlled in many people despite the availability of pharmacological interventions, evidence-based treatment guidelines and care pathways.(1) There is considerable public interest in the use of non-pharmacological approaches for the treatment of asthma.(2) A survey of people with asthma reported that many have used complementary and alternative medicine, often without the knowledge of their clinical team.(3) Such interventions include breathing techniques, herbal products, homeopathy and acupuncture. The role of breathing exercises within the management of asthma has been controversial, partly because early claims of effectiveness were exaggerated.(4) UK national guidance and international guidelines on the management of asthma have included the option of breathing exercise programmes as an adjuvant to pharmacological treatment.(5,6) Here we discuss the types of breathing exercises used and review the evidence for their effectiveness.

  15. Active control: Wind turbine model

    Energy Technology Data Exchange (ETDEWEB)

    Bindner, Henrik


    This report is a part of the reporting of the work done in the project `Active Control of Wind Turbines`. This project aim is to develop a simulation model for design of control systems for turbines with pitch control and to use that model to design controllers. This report describes the model developed for controller design and analysis. Emphasis has been put on establishment of simple models describing the dynamic behavior of the wind turbine in adequate details for controller design. This has been done with extensive use of measurements as the basis for selection of model complexity and model validation as well as parameter estimation. The model includes a simple model of the structure of the turbine including tower and flapwise blade bending, a detailed model of the gear box and induction generator, a linearized aerodynamic model including modelling of induction lag and actuator and sensor models. The models are all formulated as linear differential equations. The models are validated through comparisons with measurements performed on a Vestas WD 34 400 kW wind turbine. It is shown from a control point of view simple linear models can be used to describe the dynamic behavior of a pitch controlled wind turbine. The model and the measurements corresponds well in the relevant frequency range. The developed model is therefore applicable for controller design. (au) EFP-91. 18 ills., 22 refs.

  16. Take a Deep Breath

    Institute of Scientific and Technical Information of China (English)


    Everyone involved in Beijing’s Olympic Games held their breath last week, not because of the city’s famously polluted air , but in anticipation of the results of an experiment that could help to clean it up.

  17. Breathing difficulty - lying down (United States)

    ... short of breath. Considerations This is a common complaint in people with some types of heart or ... ADAM Health Solutions. About MedlinePlus Site Map FAQs Customer Support Get email updates Subscribe to RSS Follow ...

  18. Classifying geometric variability by dominant eigenmodes of deformation in regressing tumours during active breath-hold lung cancer radiotherapy (United States)

    Badawi, Ahmed M.; Weiss, Elisabeth; Sleeman, William C., IV; Hugo, Geoffrey D.


    The purpose of this study is to develop and evaluate a lung tumour interfraction geometric variability classification scheme as a means to guide adaptive radiotherapy and improve measurement of treatment response. Principal component analysis (PCA) was used to generate statistical shape models of the gross tumour volume (GTV) for 12 patients with weekly breath hold CT scans. Each eigenmode of the PCA model was classified as ‘trending’ or ‘non-trending’ depending on whether its contribution to the overall GTV variability included a time trend over the treatment course. Trending eigenmodes were used to reconstruct the original semi-automatically delineated GTVs into a reduced model containing only time trends. Reduced models were compared to the original GTVs by analyzing the reconstruction error in the GTV and position. Both retrospective (all weekly images) and prospective (only the first four weekly images) were evaluated. The average volume difference from the original GTV was 4.3% ± 2.4% for the trending model. The positional variability of the GTV over the treatment course, as measured by the standard deviation of the GTV centroid, was 1.9 ± 1.4 mm for the original GTVs, which was reduced to 1.2 ± 0.6 mm for the trending-only model. In 3/13 cases, the dominant eigenmode changed class between the prospective and retrospective models. The trending-only model preserved GTV and shape relative to the original GTVs, while reducing spurious positional variability. The classification scheme appears feasible for separating types of geometric variability by time trend.

  19. Comparison of two devices and two breathing patterns for exhaled breath condensate sampling.

    Directory of Open Access Journals (Sweden)

    Eva-Maria Hüttmann

    Full Text Available Analysis of exhaled breath condensate (EBC is a noninvasive method to access the epithelial lining fluid of the lungs. Due to standardization problems the method has not entered clinical practice. The aim of the study was to assess the comparability for two commercially available devices in healthy controls. In addition, we assessed different breathing patterns in healthy controls with protein markers to analyze the source of the EBC.EBC was collected from ten subjects using the RTube and ECoScreen Turbo in a randomized crossover design, twice with every device--once in tidal breathing and once in hyperventilation. EBC conductivity, pH, surfactant protein A, Clara cell secretory protein and total protein were assessed. Bland-Altman plots were constructed to display the influence of different devices or breathing patterns and the intra-class correlation coefficient (ICC was calculated. The volatile organic compound profile was measured using the electronic nose Cyranose 320. For the analysis of these data, the linear discriminant analysis, the Mahalanobis distances and the cross-validation values (CVV were calculated.Neither the device nor the breathing pattern significantly altered EBC pH or conductivity. ICCs ranged from 0.61 to 0.92 demonstrating moderate to very good agreement. Protein measurements were greatly influenced by breathing pattern, the device used, and the way in which the results were reported. The electronic nose could distinguish between different breathing patterns and devices, resulting in Mahalanobis distances greater than 2 and CVVs ranging from 64% to 87%.EBC pH and (to a lesser extent EBC conductivity are stable parameters that are not influenced by either the device or the breathing patterns. Protein measurements remain uncertain due to problems of standardization. We conclude that the influence of the breathing maneuver translates into the necessity to keep the volume of ventilated air constant in further studies.

  20. Oxygen pre-breathing decreases dysbaric diseases in UW sheep undergoing hyperbaric exposure. (United States)

    Sobakin, A S; Wilson, M A; Lehner, C E; Dueland, R T; Gendron-Fitzpatrick, A P


    Prolonged exposure of humans and animals to increased pressure as in a disabled submarine (DISSUB) can saturate the body's tissues with dissolved N2 as compressed air is breathed. Decompression-induced bubble formation in the long bone marrow cavity may lead to a bone compartment syndrome resulting in bone ischemia and necrosis. We tested oxygen pre-breathing prior to decompression in sheep to assess the effect upon dysbaric osteonecrosis (DON) induction in a DISSUB simulation experiment. A total of sixteen adult female sheep were used throughout the experiment. Four sheep were used as controls without oxygen pre-breathing. All sheep (99 +/- 14 kg SD) underwent dry chamber air exposure at 60 fsw (2.79 atm abs) (.2827 MPa) for 24 h followed by oxygen (88-92%) pre-breathing (15-min, 1-h, and 2-h and air for control) before "dropout" decompression at 30 fsw/min (0.91 atm/min). 99mTc-methylene diphosphonate (MDP) bone scans of the distal (radii and tibiae) long bones were used to detect "hot spots" of remodeling suggestive of DON lesions. Alizarin complexone fluorochrome was injected to visualize sites of metabolic activity indicating DON repair of both the proximal and distal long bones (radii, tibiae, femora, and humeri). Our findings showed that the amount of alizarin complexone deposition and bone scan uptake was greater in sheep with shorter oxygen pre-breathing times than those undergoing longer pre-breathing dives (p = 0.0056 and p = 0.001, for one and two hour pre-breathes respectively). Proximal limb bones (femur, humerus) displayed less alizarin complexone deposition than the distal radius and tibia (p < 0.0001).

  1. 呼吸运动减痛法在分娩活动中的应用%Application of Breathing Exercises Reduce Pain Method in Delivery Activities

    Institute of Scientific and Technical Information of China (English)

    张文秀; 纪利


    目的:探讨呼吸运动减痛法在分娩活动中的对产程的影响。方法将在本院产科正常待产的可行阴道分娩的200例初产妇随机平均分娩成观察组和对照组,对观察组和对照组的分娩镇痛效果,分娩方式,产程时间,产后出血量进行比较。结果与对照组相比,观察组的孕妇分娩疼痛明显减轻(P<0.01),自然分娩率提高(P<0.01),第一产程、第二产程、总产程缩短(P<0.01),产后出血量明显减少(P<0.01)。结论本研究发现,使用呼吸减痛分娩法的产妇组,增加了疼痛的耐受程度,自然分娩率大大提高,缩短了产程的时间,减少了产后出血量,有利于促进自然分娩,保障母婴健康。%Objective:To investigate the ef ect of breathing exercises reducing pain in childbirth process. Methods:200 primipara were randomly averaged divided into an observation group and a control group.To compare the pain of childbirth,mode of delivery,the birth process,amount of bleeding. Results:Compared with the control group, the children birth pain significantly reduced (P<0.01);the first stage,second stage and the total labor time shorter (P<0.01);the natural birth rate increased (P<0.01);the amount of bleeding was significantly less (P<0.01). Conclusion:Application of breathing exercises reducing pain can relieve pain of childbirth,shorten the birth process, reduce the amount of bleeding,improve the nature birth,and protect the maternal and child health.

  2. Pre-treatment urea breath test results predict the efficacy of Helicobacter pylori eradication therapy in patients with active duodenal ulcers

    Institute of Scientific and Technical Information of China (English)

    Yung-Chih Lai; Jyh-Chin Yang; Shih-Hung Huang


    AIM: To evaluate the association of pre-treatment 13C-urea breath test (UBT) results with H pyloridensity and efficacy of eradication therapy in patients with active duodenal ulcers.METHODS: One hundred and seventeen consecutive outpatients with active duodenal ulcer and H pyloriinfection were recruited. H pylori density was histologically graded according to the Sydney system. Each patient received lansoprazole (30 mg b.i.d.), clarithromycin (500 mg b.i.d.) and amoxicillin (1 g b.i.d.) for 1 week. According to pre-treatment UBT values, patients were allocated into low (<16%o),intermediate (16-35%o), and high (>35%o) UBT groups.RESULTS: A significant correlation was found between pre-treatment UBT results andHpyloridensity (P<0.001).H pylorieradication rates were 94.9%, 94.4% and 81.6%in the low, intermediate and high UBT groups, respectively (per protocol analysis, P=0.11). When patients were assigned into two groups (UBT results ≤35%o and >35%o),the eradication rates were 94.7% and 81.6%, respectively (P=0.04).CONCLUSION: The intragastric bacterial load of H pylori can be evaluated by UBT, and high pre-treatment UBT results can predict an adverse outcome of eradication therapy.

  3. 瑜伽呼吸的运用法则和训练方法%Applying Law and Training Method of Yoga Breathing

    Institute of Scientific and Technical Information of China (English)

    曹红娟; 曹元秀


    Yoga Breathing is not the unconscious and random breathing in people's daily life , it’s consciously and active breathing. Through rational adjustment and breath controlling , the lungs rhythmically contract and promote blood circulation and metabolism. In this paper , we will analyze the differences between the Yoga Breathing and the natural breath from the applying law and basic way of Yoga Breathing , and introduce some important methods of Yoga Breathing training such as the Pranayama , Bandha and Mudra.%瑜伽呼吸不是人们日常生活中那种无意识和随意式的呼吸,而是有意识的主动式呼吸,通过合理调整和控制呼吸,使肺脏发生有节律的收缩,促进体内的血液循环和新陈代谢。从瑜伽呼吸的运用法则和基本方式等方面分析其与自然呼吸的不同之处,介绍调息法、收束法和契合法等瑜伽呼吸调控训练的重要方法。

  4. Active Range of Motion with Individual Protective Equipment: Self-Contained Breathing Apparatus and Levels B and A Configurations (United States)


    CONDITIONS 27 FIGURES 1. AROM for Cervical Rotation during Head S2S Activity for Each IPE Condition 14 2. AROM for Cervical Flexion and Extension...during Head Nod Activity 14 3. AROM for Lateral Cervical Flexion to Left and Right for Head Lat Flex Activity 15 4. Left and Right Shoulder...Head Nod Cervical flexion and extension; full range of flexion and extension Head Lat Flex Left and right cervical lateral flexion ; total lateral

  5. Facilitation of breathing by leptin effects in the central nervous system. (United States)

    Bassi, M; Furuya, W I; Zoccal, D B; Menani, J V; Colombari, D S A; Mulkey, D K; Colombari, E


    With the global epidemic of obesity, breathing disorders associated with excess body weight have markedly increased. Respiratory dysfunctions caused by obesity were originally attributed to mechanical factors; however, recent studies have suggested a pathophysiological component that involves the central nervous system (CNS) and hormones such as leptin produced by adipocytes as well as other cells. Leptin is suggested to stimulate breathing and leptin deficiency causes an impairment of the chemoreflex, which can be reverted by leptin therapy. This facilitation of the chemoreflex may depend on the action of leptin in the hindbrain areas involved in the respiratory control such as the nucleus of the solitary tract (NTS), a site that receives chemosensory afferents, and the ventral surface of the medulla that includes the retrotrapezoid nucleus (RTN), a central chemosensitive area, and the rostral ventrolateral medulla (RVLM). Although the mechanisms and pathways activated by leptin to facilitate breathing are still not completely clear, evidence suggests that the facilitatory effects of leptin on breathing require the brain melanocortin system, including the POMC-MC4R pathway, a mechanism also activated by leptin to modulate blood pressure. The results of all the studies that have investigated the effect of leptin on breathing suggest that disruption of leptin signalling as caused by obesity-induced reduction of central leptin function (leptin resistance) is a relevant mechanism that may contribute to respiratory dysfunctions associated with obesity.

  6. General Anesthesia with Preserved Spontaneous Breathing through an Intubation Tube

    Directory of Open Access Journals (Sweden)

    V. V. Moroz


    Full Text Available Objective: to study whether spontaneous patient breathing may be preserved during elective operations under general anesthesia with tracheal intubation. Subjects and methods. One hundred and twelve patients undergoing elective surgeries under general endotracheal anesthesia were randomized into 2 groups: 1 patients who had forced mechanical ventilation in the volume-controlled mode and 2 those who received assisted ventilation as spontaneous breathing with mechanical support. Conclusion. The study shows that spontaneous breathing with mechanical support may be safely used during some surgical interventions in patients with baseline healthy lungs. Key words: Pressure Support, assisted ventilation, spontaneous breathing, general anesthesia, lung function.

  7. Breathing exercises for dysfunctional breathing/hyperventilation syndrome in adults



    Copyright © 2013 The Cochrane Collaboration. Published by JohnWiley & Sons, Ltd. Background: Dysfunctional breathing/hyperventilation syndrome (DB/HVS) is a respiratory disorder, psychologically or physiologically based, involving breathing too deeply and/or too rapidly (hyperventilation) or erratic breathing interspersed with breath-holding or sighing (DB). DB/HVS can result in significant patient morbidity and an array of symptoms including breathlessness, chest tightness, dizziness, tre...

  8. An assessment of overall "gain" of the O2-feedback control system with and without external dead space breathing. (United States)

    Masuyama, H; Hayashi, F; Honda, Y


    Overall gain of the O2-ventilation feedback control system (GO2) was determined in 9 male and one female healthy subjects. GO2 progressively increased with decreasing end-tidal PO2 (PETO2). This value did not exceed the overall gain of the CO2-ventilation feedback system (GCO2) even at a PETO2 level of 40 mmHg, suggesting that hypoxic stimulation did not become predominant in the present experimental condition. With addition of 250 ml of external dead space, PETO2 decrement (delta PETO2 X actual) was experimentally observed. The delta PETO2 X actual thus obtained was found to be in good agreement with the PETO2 decrement deduced from GO2 (delta PETO2 X expected). This result was similar to that found in the PETCO2 change previously seen in normoxia.


    NARCIS (Netherlands)



    The purpose of this study was to register breathing patterns, in healthy subjects, during breathing with a positive expiratory pressure. Integrated electromyographic (IEMG) activity of the following muscles was assessed: scalene muscle, parasternal muscle and abdominal muscles, using surface electro

  10. Mindful attention to breath regulates emotions via increased amygdala-prefrontal cortex connectivity. (United States)

    Doll, Anselm; Hölzel, Britta K; Mulej Bratec, Satja; Boucard, Christine C; Xie, Xiyao; Wohlschläger, Afra M; Sorg, Christian


    Mindfulness practice is beneficial for emotion regulation; however, the neural mechanisms underlying this effect are poorly understood. The current study focuses on effects of attention-to-breath (ATB) as a basic mindfulness practice on aversive emotions at behavioral and brain levels. A key finding across different emotion regulation strategies is the modulation of amygdala and prefrontal activity. It is unclear how ATB relevant brain areas in the prefrontal cortex integrate with amygdala activation during emotional stimulation. We proposed that, during emotional stimulation, ATB down-regulates activation in the amygdala and increases its integration with prefrontal regions. To address this hypothesis, 26 healthy controls were trained in mindfulness-based attention-to-breath meditation for two weeks and then stimulated with aversive pictures during both attention-to-breath and passive viewing while undergoing fMRI. Data were controlled for breathing frequency. Results indicate that (1) ATB was effective in regulating aversive emotions. (2) Left dorso-medial prefrontal cortex was associated with ATB in general. (3) A fronto-parietal network was additionally recruited during emotional stimulation. (4) ATB down regulated amygdala activation and increased amygdala-prefrontal integration, with such increased integration being associated with mindfulness ability. Results suggest amygdala-dorsal prefrontal cortex integration as a potential neural pathway of emotion regulation by mindfulness practice.

  11. The Air We Breathe (United States)

    Davila, Dina


    Topics discussed include NASA mission to pioneer the future in space exploration, scientific discovery and aeronautics research; the role of Earth's atmosphere, atmospheric gases, layers of the Earth's atmosphere, ozone layer, air pollution, effects of air pollution on people, the Greenhouse Effect, and breathing on the International Space Station.

  12. The Breath of Chemistry

    DEFF Research Database (Denmark)

    Josephsen, Jens

    The present preliminary text is a short thematic presentation in biological inorganic chemistry meant to illustrate general and inorganic (especially coordination) chemistry in biochemistry. The emphasis is on molecular models to explain features of the complicated mechanisms essential to breathing...

  13. Breathing Like a Fish (United States)

    Katsioloudis, Petros J.


    Being able to dive and breathe underwater has been a challenge for thousands of years. In 1980, Fuji Systems of Tokyo developed a series of prototype gills for divers as a way of demonstrating just how good its membranes are. Even though gill technology has not yet reached the point where recipients can efficiently use implants to dive underwater,…

  14. High Frequency Yoga Breathing: A Review of Nervous System Effects and Adjunctive Therapeutic and Premeditation Potential

    Directory of Open Access Journals (Sweden)

    Anna Andaházy


    Full Text Available High frequency yoga breathing (HFYB results in a shifting of the autonomic nervous system balance towards sympathetic nervous system dominance. In an effort to more fully understand the complex effects of this form of yogic breath-work, tests are being conducted on practitioners’ physiological and neurological response processes. Studies on heart rate variability (HRV indicating cardiac autonomic control have shown a resulting reduction of vagal activity following HFYB, leading to passive sympathetic dominance without overt excitation or exhaustion. Comparative cognitive tests taken after the practice have shown that HFYB results in reduced auditory and visual reaction times, and a decrease in optical illusion. The vigilant, wakeful, yet relaxed state induced by HFYB has been associated with improvements in attention, memory, sensorimotor performance, and mood. As breathing bridges conscious and unconscious functions, the potential role of HFYB as an adjunctive therapeutic intervention as well as its possible application in preparation for meditation is considered.

  15. Sudarshan kriya yoga: Breathing for health

    Directory of Open Access Journals (Sweden)

    Sameer A Zope


    Full Text Available Breathing techniques are regularly recommended for relaxation, stress management, control of psychophysiological states, and to improve organ function. Yogic breathing, defined as a manipulation of breath movement, has been shown to positively affect immune function, autonomic nervous system imbalances, and psychological or stress-related disorders. The aim of this study was to assess and provide a comprehensive review of the physiological mechanisms, the mind-body connection, and the benefits of Sudarshan Kriya Yoga (SKY in a wide range of clinical conditions. Various online databases searched were Medline, Psychinfo, EMBASE, and Google Scholar. All the results were carefully screened and articles on SKY were selected. The references from these articles were checked to find any other potentially relevant articles. SKY, a unique yogic breathing practice, involves several types of cyclical breathing patterns, ranging from slow and calming to rapid and stimulating. There is mounting evidence to suggest that SKY can be a beneficial, low-risk, low-cost adjunct to the treatment of stress, anxiety, post-traumatic stress disorder, depression, stress-related medical illnesses, substance abuse, and rehabilitation of criminal offenders.

  16. Pulse Ejection Presentation System Synchronized with Breathing (United States)

    Kadowaki, Ami; Sato, Junta; Ohtsu, Kaori; Bannai, Yuichi; Okada, Kenichi

    Trials on transmission of olfactory information together with audio/visual information are currently being conducted in the field of multimedia. However, continuous emission of scents in high concentration creates problems of human adaptation and remnant odors in air. To overcome such problems we developed an olfactory display in conjunction with Canon Inc. This display has high emission control in the ink-jet so that it can provide stable pulse emission of scents. Humans catch a scent when they breathe in and inhale smell molecules in air. Therefore, it is important that the timing of scent presentation is synchronized with human breathing. We also developed a breath sensor which detects human inspiration. In this study, we combined the olfactory display with the breath sensor to make a pulse ejection presentation system synchronized the breath. The experimental evaluation showed that the system had more than 90 percent of detection rate. Another evaluation was held at KEIO TECHNO-MALL 2007. From questionnaire results of the participants, we found that the system made the user feel continuous sense of smell avoiding adaptation. It is expected that our system enables olfactory information to be synchronized with audio/visual information in arbitrary duration at any time.

  17. A Higher Proportion of Metabolic Syndrome in Chinese Subjects with Sleep-Disordered Breathing: A Case-Control Study Based on Electrocardiogram-Derived Sleep Analysis (United States)

    Tseng, Ping-Huei; Lee, Pei-Lin; Hsu, Wei-Chung; Ma, Yan; Lee, Yi-Chia; Chiu, Han-Mo; Ho, Yi-Lwun; Chen, Ming-Fong; Wu, Ming-Shiang; Peng, Chung-Kang


    Objective The prevalence of metabolic syndrome (MS) has increased rapidly in Taiwan and worldwide. We aim to determine the association between sleep-disordered breathing (SDB) and MS in a Chinese general population. Methods This case-control study recruited subjects who have undergone a prospective electrocardiogram-based cardiopulmonary coupling (CPC) sleep spectrogram as part of the periodic health check-ups at the National Taiwan University Hospital. Comprehensive anthropometrics, blood biochemistry, prevalence of MS and its individual components were compared with Bonferroni correction between 40 subjects with SDB, defined as the CPC-derived apnea–hypopnea index (CPC-AHI) >5 event/hour and 80 age- and sex-matched controls, defined as CPC-AHI <1 event/hour. MS was diagnosed based on the Adult Treatment Panel III, with a modification of waist circumference for Asians. Results Subjects with SDB were more obese with larger waist circumferences (95.1±12.9 vs. 87.3±6.9, P < .001) and borderline higher BMI (27.0±4.9 vs. 24.3±2.5, P = .002). Waist circumference was independently associated with the presence of SDB after adjustment for BMI, systolic blood pressure and fasting blood glucose in multiple regression analyses. Subjects with SDB had a higher prevalence of central obesity (72.5% vs. 42.5%, P = .002), hyperglycemia (45.0% vs. 26.3%, P = .04), MS (45.0% vs. 22.5%, P = .01) and number of MS components (2.4 ± 1.6 vs. 1.7 ± 1.4, P = .01) than the control group. Waist circumference was significantly correlated with both CPC-AHI (r = .492, P = .0013) and PSG-AHI (r = .699, P < .0001) in the SDB group. Conclusions SDB was associated with a higher prevalence of MS and its individual components, notably central obesity, in a Chinese general population. Large-scale screening of high risk population with MS to identify subjects with SDB for appropriate management is warranted. PMID:28081171

  18. Study of the correlations between fractional exhaled nitric oxide in exhaled breath and atopic status, blood eosinophils, FCER2 mutation, and asthma control in Vietnamese children

    Directory of Open Access Journals (Sweden)

    Nguyen-Thi-Bich H


    Full Text Available Hanh Nguyen-Thi-Bich,1 Huong Duong-Thi-Ly,2 Vu Thi Thom,2 Nhung Pham-Thi-Hong,2 Long Doan Dinh,2 Huong Le-Thi-Minh,1 Timothy John Craig,3 Sy Duong-Quy3,4 1Department of Immunology, Allergology, and Rheumatology, National Hospital of Pediatrics, Hanoi, Vietnam; 2School of Medicine and Pharmacy, Vietnam National University Hanoi, Vietnam; 3Department of Medicine, Penn State University, Hershey, PA, USA; 4Department of Respiratory Diseases, Lam Dong Medical College, Dalat, Vietnam Introduction: Fractional exhaled nitric oxide (FENO is a biomarker of airway inflammation in asthma. The measurement of FENO is utilized to assist in the diagnosis and treatment of children with asthma, especially for those treated with inhaled corticosteroids. Objectives: The aims of this study were to evaluate the correlations between FENO and atopic status, blood eosinophil levels, FCER2 mutation, and asthma control in Vietnamese children. Subjects and methods: This was a prospective and descriptive study approved by the local Ethical Board. All children with uncontrolled asthma, seen in the National Hospital of Pediatrics (Hanoi, Vietnam, were included. Exhaled breath FENO, blood eosinophils, skin prick test, total IgE, asthma control test (ACT, and FCER2 gene polymorphism were performed at inclusion. They were followed up at 3 months to evaluate clinical status, FENO levels, and ACT. Results: Forty-two children with uncontrolled asthma with a mean age of 10±3 years (6–16 years were included. The male/female ratio was 2.5/1. The mean FENO levels were 26±25 ppb. FENO was significantly higher in patients with a positive skin prick test for respiratory allergens (P<0.05. FENO was significantly correlated with blood eosinophil levels (r=0.5217; P=0.0004. Five of the 32 subjects (15.6% had a mutation of FCER2 gene (rs28364072 SNP. In this group, the levels of FENO were highest (37±10 ppb; P<0.05. The levels of FENO were significantly decreased after 3 months of

  19. BREATH: Web-Based Self-Management for Psychological Adjustment After Primary Breast Cancer--Results of a Multicenter Randomized Controlled Trial

    NARCIS (Netherlands)

    Berg, S.W. van den; Gielissen, M.F.M.; Custers, J.A.E.; Graaf, W.T.A. van der; Ottevanger, P.B.; Prins, J.B.


    PURPOSE: Early breast cancer survivors (BCSs) report high unmet care needs, and easily accessible care is not routinely available for this growing population. The Breast Cancer E-Health (BREATH) trial is a Web-based self-management intervention to support the psychological adjustment of women after

  20. Effect of device-guided breathing exercises on blood pressure in hypertensive patients with type 2 diabetes mellitus : A randomized controlled trial

    NARCIS (Netherlands)

    Logtenberg, Susan J.; Kleefstra, Nanne; Houweling, Sebastlaan T.; Groenier, Klaas H.; Bilo, Henk J.


    Objective In patients with type 2 diabetes mellitus (DM2), it is hard to reach treatment objectives for blood pressure (BP) with classical treatment options. Recently, reducing breathing frequency has been advocated as a method to reduce BP. We examined if an electronic device such as Resperate, by

  1. 吸气式空天飞行器飞行控制方法探析%General Analysis on Flight Control Method of Air-breathing Aerospace Plane

    Institute of Scientific and Technical Information of China (English)

    姚宗信; 李仁府; 李爱军


    It is our objective to research the nonlinear control dififcult problem of the air-breathing aerospace plane with strong coupling between aerodynamics, propulsion, and structure. First, the analysis was done to understand the reason of resulting in those strong coupling and the dififculty of lfight control. Second, it was analyzed how several advanced control theory methods were applied to the air-breathing aerospace plane. Third, the method of designing two controllers based respectively on high-order sliding mode and robust-adaptive was explored for the air-breathing aerospace plane, and the primary idea of two controllers was embodied. Finally, the potential of two controllers was evaluated.%针对“吸气式空天飞行器(气动/动力/结构)强耦合特性引起的不确定非线性控制”问题,首先,分析了引起吸气式空天飞行器强耦合特性的原因及其对飞行控制的不利影响;然后,剖析了可用于吸气式空天飞行器控制的四种典型理论方法;之后,针对吸气式空天飞行器模型的非线性和不确定性,探索了基于高阶滑模和鲁棒自适应两种理论的飞行控制方法,给出了具体的控制器设计思想;最后,评价了两种控制方法应用于吸气式空天飞行器的优势和局限性。

  2. Learn More Breathe Better

    Centers for Disease Control (CDC) Podcasts


    Chronic obstructive pulmonary disease (COPD) is a serious lung disease that makes breathing very difficult and can affect your quality of life. Learn the causes of COPD and what you can do to prevent it.  Created: 11/16/2011 by National Center for Chronic Disease Prevention and Health Promotion, Division of Adult and Community Health (NCCDPHP, DACH).   Date Released: 11/16/2011.

  3. Relationship between Musical Characteristics and Temporal Breathing Pattern in Piano Performance


    Yutaka Sakaguchi; Eriko Aiba


    Although there is growing evidence that breathing is modulated by various motor and cognitive activities, the nature of breathing in musical performance has been little explored. The present study examined the temporal breath pattern in piano performance, aiming to elucidate how breath timing is related to musical organization/events and performance. In the experiments, the respiration of 15 professional and amateur pianists, playing 10 music excerpts in total (from four-octave C major scale,...

  4. Differential effects of low-intensity motor cortical stimulation on the inspiratory activity in scalene muscles during voluntary and involuntary breathing

    DEFF Research Database (Denmark)

    Petersen, Nicolas Caesar; Taylor, Janet L; Murray, Nicholas P S;


    To assess the cortical contribution to breathing, low-intensity transcranial magnetic stimulation (TMS) was delivered over the motor cortex in 10 subjects during: (i) voluntary static inspiratory efforts, (ii) hypocapnic voluntary ventilation (end-tidal CO(2), 2.7±0.4% mean±SD), and (iii) hyperca...

  5. Influence of condensation temperature on selected exhaled breath parameters

    Directory of Open Access Journals (Sweden)

    Manini Paola


    Full Text Available Abstract Background The effects of changes in cooling temperature on biomarker levels in exhaled breath condensate have been little investigated. The aim of the study was to test the effect of condensation temperature on the parameters of exhaled breath condensate and the levels of selected biomarkers. Methods Exhaled breath condensate was collected from 24 healthy subjects at temperatures of -10, -5, 0 and +5 C degrees. Selected parameters (condensed volume and conductivity and biomarkers (hydrogen peroxide, malondialdehyde were measured. Results There was a progressive increase in hydrogen peroxide and malondialdehyde concentrations, and condensate conductivity as the cooling temperature increased; total condensate volume increased as the cooling temperature decreased. Conclusion The cooling temperature of exhaled breath condensate collection influenced selected biomarkers and potential normalizing factors (particularly conductivity in different ways ex vivo. The temperature of exhaled breath condensate collection should be controlled and reported.

  6. Fast and accurate exhaled breath ammonia measurement. (United States)

    Solga, Steven F; Mudalel, Matthew L; Spacek, Lisa A; Risby, Terence H


    This exhaled breath ammonia method uses a fast and highly sensitive spectroscopic method known as quartz enhanced photoacoustic spectroscopy (QEPAS) that uses a quantum cascade based laser. The monitor is coupled to a sampler that measures mouth pressure and carbon dioxide. The system is temperature controlled and specifically designed to address the reactivity of this compound. The sampler provides immediate feedback to the subject and the technician on the quality of the breath effort. Together with the quick response time of the monitor, this system is capable of accurately measuring exhaled breath ammonia representative of deep lung systemic levels. Because the system is easy to use and produces real time results, it has enabled experiments to identify factors that influence measurements. For example, mouth rinse and oral pH reproducibly and significantly affect results and therefore must be controlled. Temperature and mode of breathing are other examples. As our understanding of these factors evolves, error is reduced, and clinical studies become more meaningful. This system is very reliable and individual measurements are inexpensive. The sampler is relatively inexpensive and quite portable, but the monitor is neither. This limits options for some clinical studies and provides rational for future innovations.

  7. Rationale of the BREAst cancer e-healTH [BREATH] multicentre randomised controlled trial: An Internet-based self-management intervention to foster adjustment after curative breast cancer by decreasing distress and increasing empowerment

    Directory of Open Access Journals (Sweden)

    van den Berg Sanne W


    Full Text Available Abstract Background After completion of curative breast cancer treatment, patients go through a transition from patient to survivor. During this re-entry phase, patients are faced with a broad range of re-entry topics, concerning physical and emotional recovery, returning to work and fear of recurrence. Standard and easy-accessible care to facilitate this transition is lacking. In order to facilitate adjustment for all breast cancer patients after primary treatment, the BREATH intervention is aimed at 1 decreasing psychological distress, and 2 increasing empowerment, defined as patients’ intra- and interpersonal strengths. Methods/design The non-guided Internet-based self-management intervention is based on cognitive behavioural therapy techniques and covers four phases of recovery after breast cancer (Looking back; Emotional processing; Strengthening; Looking ahead. Each phase of the fully automated intervention has a fixed structure that targets consecutively psychoeducation, problems in everyday life, social environment, and empowerment. Working ingredients include Information (25 scripts, Assignment (48 tasks, Assessment (10 tests and Video (39 clips extracted from recorded interviews. A non-blinded, multicentre randomised controlled, parallel-group, superiority trial will be conducted to evaluate the effectiveness of the BREATH intervention. In six hospitals in the Netherlands, a consecutive sample of 170 will be recruited of women who completed primary curative treatment for breast cancer within 4 months. Participants will be randomly allocated to receive either usual care or usual care plus access to the online BREATH intervention (1:1. Changes in self-report questionnaires from baseline to 4 (post-intervention, 6 and 10 months will be measured. Discussion The BREATH intervention provides a psychological self-management approach to the disease management of breast cancer survivors. Innovative is the use of patients’ own strengths

  8. Quantitative Analysis of Periodic Breathing and Very Long Apnea in Preterm Infants (United States)

    Mohr, Mary A.

    Electronic signals from bedside monitors in University of Virginia's Neonatal Intensive Care Unit (NICU) are routinely collected and stored. The overall goal of our research is predictive monitoring: we seek patterns in signals that give early warning of impending pathology. This work focuses on apnea (pauses in regular respiration), and on periodic breathing (regular cycles of breathing and apnea). Our examination of apnea events revealed a disturbing number of cases in which the cessation of breathing lasted at least 60 seconds. These observations were validated, clinical correlations of these events were identified, and a theory was developed that partially explains how they occur. Periodic breathing in neonates is a normal developmental phenomenon. It arises when there is instability in the respiratory control system. A mathematical model of periodic breathing was developed to analyze the stability of the control system in infants. Periodic breathing has long been thought to be benign, however, exaggerated durations of periodic breathing may be an indicator of pathology. Characterization of periodic breathing has previously been limited to short monitoring times in small numbers of infants. An automated system for measurement and characterization of periodic breathing was developed and applied to 5 years of data from the NICU. The amount of periodic breathing that infants had was found to increase with gestational age (up to 32 weeks). Also, times of excessive periodic breathing were recorded and clinical correlations were sought. A significant increase in periodic breathing in the 24 hours before diagnosis of necrotizing enterocolitis was found.

  9. Effect of a single breath of 100% oxygen on respiration in neonates during sleep. (United States)

    Aizad, T; Bodani, J; Cates, D; Horvath, L; Rigatto, H


    To determine the effect of a single breath of 100% O2 on ventilation, 10 full-term [body wt 3,360 +/- 110 (SE) g, gestational age 39 +/- 0.4 wk, postnatal age 3 +/- 0.6 days] and 10 preterm neonates (body wt 2,020 +/- 60 g, gestational age 34 +/- 2 wk, postnatal age 9 +/- 2 days) were studied during active and quiet sleep states. The single-breath method was used to measure peripheral chemoreceptor response. To enhance response and standardize the control period for all infants, fractional inspired O2 concentration was adjusted to 16 +/- 0.6% for a control O2 saturation of 83 +/- 1%. After 1 min of control in each sleep state, each infant was given a single breath of O2 followed by 21% O2. Minute ventilation (VE), tidal volume (VT), breathing frequency (f), alveolar O2 and CO2 tension, O2 saturation (ear oximeter), and transcutaneous O2 tension were measured. VE always decreased with inhalation of O2 (P less than 0.01). In quiet sleep, the decrease in VE was less in full-term (14%) than in preterm (40%) infants (P less than 0.001). Decrease in VE was due primarily to a drop in VT in full-term infants as opposed to a fall in f and VT in preterm infants (P less than 0.05). Apnea, as part of the response, was more prevalent in preterm than in full-term infants. In active sleep the decrease in VE was similar both among full-term (19%) and preterm (21%) infants (P greater than 0.5). These results suggest greater peripheral chemoreceptor response in preterm than in full-term infants, reflected by a more pronounced decrease in VE with O2. The results are compatible with a more powerful peripheral chemoreceptor contribution to breathing in preterm than in full-term infants.

  10. Developing Internal Controls through Activities (United States)

    Barnes, F. Herbert


    Life events can include the Tuesday afternoon cooking class with the group worker or the Saturday afternoon football game, but in the sense that Fritz Redl thought of them, these activities are only threads in a fabric of living that includes all the elements of daily life: playing, working, school-based learning, learning through activities,…

  11. Vibration control of active structures an introduction

    CERN Document Server

    Preumont, Andre


    This text is an introduction to the dynamics of active structures and to the feedback control of lightly damped flexible structures. The emphasis is placed on basic issues and simple control strategies that work.

  12. Evaluation of Fractional Regional Ventilation Using 4D-CT and Effects of Breathing Maneuvers on Ventilation

    Energy Technology Data Exchange (ETDEWEB)

    Mistry, Nilesh N., E-mail: [Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, Maryland (United States); Diwanji, Tejan; Shi, Xiutao [Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, Maryland (United States); Pokharel, Sabin [Morgan State University, Baltimore, Maryland (United States); Feigenberg, Steven [Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, Maryland (United States); Scharf, Steven M. [Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland (United States); D' Souza, Warren D. [Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, Maryland (United States)


    Purpose: Current implementations of methods based on Hounsfield units to evaluate regional lung ventilation do not directly incorporate tissue-based mass changes that occur over the respiratory cycle. To overcome this, we developed a 4-dimensional computed tomography (4D-CT)-based technique to evaluate fractional regional ventilation (FRV) that uses an individualized ratio of tidal volume to end-expiratory lung volume for each voxel. We further evaluated the effect of different breathing maneuvers on regional ventilation. The results from this work will help elucidate the relationship between global and regional lung function. Methods and Materials: Eight patients underwent 3 sets of 4D-CT scans during 1 session using free-breathing, audiovisual guidance, and active breathing control. FRV was estimated using a density-based algorithm with mass correction. Internal validation between global and regional ventilation was performed by use of the imaging data collected during the use of active breathing control. The impact of breathing maneuvers on FRV was evaluated comparing the tidal volume from 3 breathing methods. Results: Internal validation through comparison between the global and regional changes in ventilation revealed a strong linear correlation (slope of 1.01, R{sup 2} of 0.97) between the measured global lung volume and the regional lung volume calculated by use of the “mass corrected” FRV. A linear relationship was established between the tidal volume measured with the automated breathing control system and FRV based on 4D-CT imaging. Consistently larger breathing volumes were observed when coached breathing techniques were used. Conclusions: The technique presented improves density-based evaluation of lung ventilation and establishes a link between global and regional lung ventilation volumes. Furthermore, the results obtained are comparable with those of other techniques of functional evaluation such as spirometry and hyperpolarized-gas magnetic

  13. Aspiration tests in aqueous foam using a breathing simulator

    Energy Technology Data Exchange (ETDEWEB)

    Archuleta, M.M.


    Non-toxic aqueous foams are being developed by Sandia National Laboratories (SNL) for the National Institute of Justice (NIJ) for use in crowd control, cell extractions, and group disturbances in the criminal justice prison systems. The potential for aspiration of aqueous foam during its use and the resulting adverse effects associated with complete immersion in aqueous foam is of major concern to the NIJ when examining the effectiveness and safety of using this technology as a Less-Than-Lethal weapon. This preliminary study was designed to evaluate the maximum quantity of foam that might be aspirated by an individual following total immersion in an SNL-developed aqueous foam. A.T.W. Reed Breathing simulator equipped with a 622 Silverman cam was used to simulate the aspiration of an ammonium laureth sulfate aqueous foam developed by SNL and generated at expansion ratios in the range of 500:1 to 1000:1. Although the natural instinct of an individual immersed in foam is to cover their nose and mouth with a hand or cloth, thus breaking the bubbles and decreasing the potential for aspiration, this study was performed to examine a worst case scenario where mouth breathing only was examined, and no attempt was made to block foam entry into the breathing port. Two breathing rates were examined: one that simulated a sedentary individual with a mean breathing rate of 6.27 breaths/minute, and one that simulated an agitated or heavily breathing individual with a mean breathing rate of 23.7 breaths/minute. The results of this study indicate that, if breathing in aqueous foam without movement, an air pocket forms around the nose and mouth within one minute of immersion.

  14. 42 CFR 84.81 - Compressed breathing gas and liquefied breathing gas containers; minimum requirements. (United States)


    ... 42 Public Health 1 2010-10-01 2010-10-01 false Compressed breathing gas and liquefied breathing... APPROVAL OF RESPIRATORY PROTECTIVE DEVICES Self-Contained Breathing Apparatus § 84.81 Compressed breathing gas and liquefied breathing gas containers; minimum requirements. (a) Compressed breathing gas...

  15. An Improved Production Activity Control Architecture for Shop Floor Control

    Institute of Scientific and Technical Information of China (English)

    SHAHIDIkramullahButt; SUNHou-fang; HAMIDUllahKhanNiazi


    This paper presents a further improved Production Activity Control Architecture to deal with the complexity of information by creating Sub-Producers and Sub-Movers which will not only give a better control at workstation level but also reduce load on the Dispatcher. It also makes an analysis of the basic and improved PAC (Production Activity Control) Architecture in the Control System for Integrated Manufacturing. The PAC Architecture and the improvement will further enhance the flexibility and adaptability of the architecture in the ever changing environment of the Shop Floor Control (SFC) Systems.

  16. Tongue Scrapers Only Slightly Reduce Bad Breath (United States)

    ... your desktop! more... Tongue Scrapers Only Slightly Reduce Bad Breath Article Chapters Tongue Scrapers Only Slightly Reduce ... oral cavity. Reviewed: January 2012 Related Articles: Halitosis (Bad Breath) Do You Have Traveler's Breath? Does a ...

  17. Breath in the technoscientific imaginary. (United States)

    Rose, Arthur


    Breath has a realist function in most artistic media. It serves to remind the reader, the viewer or the spectator of the exigencies of the body. In science fiction (SF) literature and films, breath is often a plot device for human encounters with otherness, either with alien peoples, who may not breathe oxygen, or environments, where there may not be oxygen to breathe. But while there is a technoscientific quality to breath in SF, especially in its attention to physiological systems, concentrating on the technoscientific threatens to occlude other, more affective aspects raised by the literature. In order to supplement the tendency to read SF as a succession of technoscientific accounts of bodily experience, this paper recalls how SF texts draw attention to the affective, non-scientific qualities of breath, both as a metonym for life and as a metaphor for anticipation. Through an engagement with diverse examples from SF literature and films, this article considers the tension between technoscientific and affective responses to breath in order to demonstrate breath's co-determinacy in SF's blending of scientific and artistic discourses.

  18. BREATHE to Understand© (United States)

    Swisa, Maxine


    BREATHE is an acronym for Breathe, Reflect, Empathize, Accept, Thank, Hearten, Engage. The addition of Understand allows for a holistic approach to living a healthy and balanced life both inside and outside the classroom. This paper took form as a result of my personal, spiritual journey, as well as my teaching practice. I noticed that the…

  19. FMWC Radar for Breath Detection

    DEFF Research Database (Denmark)

    Suhr, Lau Frejstrup; Tafur Monroy, Idelfonso; Vegas Olmos, Juan José

    We report on the experimental demonstration of an FMCW radar operating in the 25.7 - 26.6 GHz range with a repetition rate of 500 sweeps per second. The radar is able to track the breathing rate of an adult human from a distance of 1 meter. The experiments have utilized a 50 second recording window...... to accurately track the breathing rate. The radar utilizes a saw tooth modulation format and a low latency receiver. A breath tracking radar is useful both in medical scenarios, diagnosing disorders such as sleep apnea, and for home use where the user can monitor its health. Breathing is a central part of every...... radar chip which, through the use of a simple modulation scheme, is able to measure the breathing rate of an adult human from a distance. A high frequency output makes sure that the radar cannot penetrate solid obstacles which is a wanted feature in private homes where people therefore cannot measure...

  20. A control system for mechanical ventilation of passive and active subjects. (United States)

    Tehrani, Fleur T


    Synchronization of spontaneous breathing with breaths supplied by the ventilator is essential for providing optimal ventilation to patients on mechanical ventilation. Some ventilation techniques such as Adaptive Support Ventilation (ASV), Proportional Assist Ventilation (PAV), and Neurally Adjusted Ventilatory Assist (NAVA) are designed to address this problem. In PAV, the pressure support is proportional to the patient's ongoing effort during inspiration. However, there is no guarantee that the patient receives adequate ventilation. The system described in this article is designed to automatically control the support level in PAV to guarantee delivery of patient's required ventilation. This system can also be used to control the PAV support level based on the patient's work of breathing. This technique further incorporates some of the features of ASV to deliver mandatory breaths for passive subjects. The system has been tested by using computer simulations and the controller has been implemented by using a prototype.

  1. Automobile active suspension system with fuzzy control

    Institute of Scientific and Technical Information of China (English)

    刘少军; 黄中华; 陈毅章


    A quarter-automobile active suspension model was proposed. High speed on/off solenoid valves were used as control valves and fuzzy control was chosen as control method . Based on force analyses of system parts, a mathematical model of the active suspension system was established and simplified by linearization method. Simulation study was conducted with Matlab and three scale coefficients of fuzzy controller (ke, kec, ku) were acquired. And an experimental device was designed and produced. The results indicate that the active suspension system can achieve better vibration isolation performance than passive suspension system, the displacement amplitude of automobile body can be reduced to 55%. Fuzzy control is an effective control method for active suspension system.


    Institute of Scientific and Technical Information of China (English)


    Nonlinear control methods are presented based on theory of sliding mode control (SMC) or variable structure control (VSC) for application to active automobile suspensions. Requirements of reducing manufacturing cost and energy consumption of the active suspension system may be satisfiedby reasonable design of the sliding surface and hydraulic servo system. Emphasis is placed on the study of the discrete sliding mode control method (DSMC) applicable for a new sort of speed on-off solenoid valves of anti-dust capability and low price. Robustness and effectiveness of the feedback linearized controller in typical road conditions are demonstrated by numerical results fora quarter-car suspension model.

  3. Breathing abnormalities in a female mouse model of Rett syndrome. (United States)

    Johnson, Christopher M; Cui, Ningren; Zhong, Weiwei; Oginsky, Max F; Jiang, Chun


    Rett syndrome (RTT) is a female neurodevelopmental disease with breathing abnormalities. To understand whether breathing defects occur in the early lives of a group of female Mecp2(+/-) mice, a mouse model of RTT, and what percentage of mice shows RTT-like breathing abnormality, breathing activity was measured by plethysmography in conscious mice. Breathing frequency variation and central apnea in a group of Mecp2(+/-) females displayed a distribution pattern similar to Mecp2(-/Y) males, while the rest resembled the wild-type mice. Similar results were obtained using the k-mean clustering statistics analysis. With two independent methods, about 20% of female Mecp2(+/-) mice showed RTT-like breathing abnormalities that began as early as 3 weeks of age in the Mecp2(+/-) mice, and were suppressed with 3% CO2. The finding that only a small proportion of Mecp2(+/-) mice develops RTT-like breathing abnormalities suggests incomplete allele inactivation in the RTT-model Mecp2(+/-) mice.

  4. Activities of the control services; Activites des services du controle

    Energy Technology Data Exchange (ETDEWEB)



    This paper summarizes the control activities of the technical service of electric power and big dams: annual examinations, administrative instructions (draining, floods, granting renewal), decennial examinations etc. (J.S.)

  5. Active Control of Fan Noise

    Institute of Scientific and Technical Information of China (English)

    Nobuhiko YAMASAKI; Hirotoshi TAJIMA


    In the wake-rotor interaction fan noise, a number of the interacting modes at the blade passing frequency (BPF)and its harmonics are generated which are prescribed by the number of stator and rotor blades etc. In the present study, the dominant mode is tried to be suppressed by the secondary sound from the loudspeaker actuators. One of the novel features of the present system is the adoption of the control board with the Field Programmable Gate Array (FPGA) hardware and the LabVIEW software to synchronize the circumferentially installed loudspeaker actuators with the relative location of rotational blades under arbitrary fan rotational speeds. The experiments were conducted under the conditions of three rotational speeds of 2004, 3150, and 4002 [rpm]. The reduction in the sound pressure level (SPL) was observed for all three rotational speeds. The sound pressure level at the BPF was reduced approximately 13 [dB] for 2004 [rpm] case, but not so large reduction was attained for other cases probably due to the inefficiency of the loudspeaker actuators at high frequencies

  6. Reduced cardiac autonomic response to deep breathing: A heritable vulnerability trait in patients with schizophrenia and their healthy first-degree relatives. (United States)

    Liu, Yu-Wen; Tzeng, Nian-Sheng; Yeh, Chin-Bin; Kuo, Terry B J; Huang, San-Yuan; Chang, Chuan-Chia; Chang, Hsin-An


    Reduced resting heart rate variability (HRV) has been observed in patients with schizophrenia and their relatives, suggesting genetic predispositions. However, findings have not been consistent. We assessed cardiac autonomic response to deep breathing in first-degree relatives of patients with schizophrenia (n=45; 26 female; aged 39.69±14.82 years). Data were compared to healthy controls (n=45; 26 female; aged 38.27±9.79 years) matched for age, gender, body mass index and physical activity as well as to unmedicated patients with acute schizophrenia (n=45; 25 female; aged 37.31±12.65 years). Electrocardiograms were recorded under supine resting and deep-breathing conditions (10-12breaths/min). We measured HRV components including variance, low-frequency (LF) power, which may reflect baroreflex function, high-frequency (HF) power, which reflects cardiac parasympathetic activity, and LF/HF ratio, which may reflect sympatho-vagal balance. Patients rather than relatives exhibited lower resting-state HRV (variance, LF, and HF) than controls. As expected, deep breathing induced an increase in variance and HF-HRV in controls. However, such a response was significantly reduced in both patients and their relatives. In conclusion, the diminished cardiac autonomic reactivity to deep breathing seen in patients and their unaffected relatives indicates that this pattern of cardiac autonomic dysregulation may be regarded as a genetic trait marker for schizophrenia.

  7. [Rates of breathing values and kinetics of respiration response in critical patterns of muscular activity in middle and long distance running]. (United States)

    Volkov, N I; Kornienko, T G; Tambovtseva, R V


    Parameters of ventilation influx, ventilation debt and ventilation demand of exercise were calculated on the basis of heart rate dynamics and parameters of external breathing during the testing procedure and recovery of elite runners during of the maximum workout. It was established that all of external breathing values closely reproduce changes of basic parameters of oxygen demand during the exercises at high intensity and duration and can be used for quantification and valuation of exercise loads in sport. During the conducted at the research it was experimentally proved that high level of sporting achievements in middle and long distance running is defined by three major factors of an aerobic exchange in an organism: 1. General ratio of increase in level of pulmonary ventilation (VE), consumption of oxygen (VO2) and allocation of carbon dioxide (CO2); 2. During the expiration--rate and of supply speed of oxygen (O2) from lungs to working muscles; 3. Rate of oxygenation (StO2) and total speed of the blood-groove.

  8. Visualizing Breath using Digital Holography (United States)

    Hobson, P. R.; Reid, I. D.; Wilton, J. B.


    Artist Jayne Wilton and physicists Peter Hobson and Ivan Reid of Brunel University are collaborating at Brunel University on a project which aims to use a range of techniques to make visible the normally invisible dynamics of the breath and the verbal and non-verbal communication it facilitates. The breath is a source of a wide range of chemical, auditory and physical exchanges with the direct environment. Digital Holography is being investigated to enable a visually stimulating articulation of the physical trajectory of the breath as it leaves the mouth. Initial findings of this research are presented. Real time digital hologram replay allows the audience to move through holographs of breath-born particles.

  9. Active load control techniques for wind turbines.

    Energy Technology Data Exchange (ETDEWEB)

    van Dam, C.P. (University of California, Davis, CA); Berg, Dale E.; Johnson, Scott J. (University of California, Davis, CA)


    This report provides an overview on the current state of wind turbine control and introduces a number of active techniques that could be potentially used for control of wind turbine blades. The focus is on research regarding active flow control (AFC) as it applies to wind turbine performance and loads. The techniques and concepts described here are often described as 'smart structures' or 'smart rotor control'. This field is rapidly growing and there are numerous concepts currently being investigated around the world; some concepts already are focused on the wind energy industry and others are intended for use in other fields, but have the potential for wind turbine control. An AFC system can be broken into three categories: controls and sensors, actuators and devices, and the flow phenomena. This report focuses on the research involved with the actuators and devices and the generated flow phenomena caused by each device.

  10. Classifying controllers by activities : An exploratory study

    NARCIS (Netherlands)

    Verstegen, B.; De Loo, I.G.M.; Mol, P.; Slagter, K.; Geerkens, H.


    The goal of this paper is to discern variables (triggers) that affect a controller’s role in an organisation. Using survey data, groups of controllers are distinguished based on coherent combinations of activities. We find that controllers either operate as so-called ‘information adapters’ or ‘watch

  11. Active and passive vibration control of structures

    CERN Document Server

    Spelsberg-Korspeter, Gottfried


    Active and Passive Vibration Control of Structures form an issue of very actual interest in many different fields of engineering, for example in the automotive and aerospace industry, in precision engineering (e.g. in large telescopes), and also in civil engineering. The papers in this volume bring together engineers of different background, and it fill gaps between structural mechanics, vibrations and modern control theory.  Also links between the different applications in structural control are shown.

  12. The effects of slow breathing on affective responses to pain stimuli: an experimental study. (United States)

    Zautra, Alex J; Fasman, Robert; Davis, Mary C; Craig, Arthur D Bud


    This study examined whether breathing rate affected self-reported pain and emotion following thermal pain stimuli in women with fibromyalgia syndrome (FM: n=27) or age-matched healthy control women (HC: n=25). FM and HC were exposed to low and moderate thermal pain pulses during paced breathing at their normal rate and one-half their normal rate. Thermal pain pulses were presented in four blocks of four trials. Each block included exposure to both mild and moderate pain trials, and periods of both normal and slow paced breathing. Pain intensity and unpleasantness were recorded immediately following each pain trial, and positive and negative affect were assessed at the end of each block of trials. Compared to normal breathing, slow breathing reduced ratings of pain intensity and unpleasantness, particularly for moderately versus mildly painful thermal stimuli. The effects of slow breathing on pain ratings were less reliable for FM patients than for HCs. Slow versus normal breathing decreased negative affect ratings following thermal pain pulses for both groups, and increased positive affect reports, but only for healthy controls with high trait negative affect. Participants who reported higher levels of trait positive affect prior to the experiment showed greater decreases in negative affect as a result of slow versus normal breathing. These experimental findings provide support for prior reports on the benefits of yogic breathing and mindful Zen meditation for pain and depressed affect. However, chronic pain patients may require more guidance to obtain therapeutic benefit from reduced breathing rates.

  13. Foundations of Active Control - Active Noise Reduction Helmets

    DEFF Research Database (Denmark)

    Elmkjær, Torsten Haaber Leth


    This Ph.D. thesis includes fundamental considerations about topologies, algorithms, implementations, methods etc., that can enter in the next generation of active control (AC) systems. Specifically, a new variant of feedforward control referred to as confined feedforward active control (CFFAC......-output (MIMO) system that facilitates both feedforward and feedback control. The general system is then referred to as hybrid MIMO confined-feedforward feedback (HMIMOCFFFB) active noise reduction (ANR) system. The investigation of a multi-channel ANR system with hybrid feedforward and feedback topologies...... performance. It is common engineering practice to apply an assumption of Gaussian distributed signals. However, many phenomena encountered in daily life fall into a generalization of the normal distribution that is referred to as α-stable distributions. Noise sources encountered in the domain of AC...


    Directory of Open Access Journals (Sweden)

    Felicia Sabou


    Full Text Available The paper focused on importance and benefits of control and evaluation of marketing activities. The control of efficiency review the assessment of the resources for marketing activity, checking also the efficiency of the human resources, advertising, promotion activities and distribution activities. In the analyse of human resources the most important ratio are: the average of costumers visits on a day, the number of custom order received from 100 visits, the number of new customers from a period, the number of lost customers from a period, the marketing human expenditures from all the sales.The strategic control is made to check if the objectives and the company strategy are adapted to the marketing environment.

  15. Active control of robot manipulator compliance (United States)

    Nguyen, C. C.; Pooran, F. J.


    Work performed at Catholic University on the research grant entitled Active Control of Robot Manipulator Compliance, supported by NASA/Goddard space Flight Center during the period of May 15th, 1986 to November 15th, 1986 is described. The modelling of the two-degree-of-freedom robot is first presented. Then the complete system including the robot and the hybrid controller is simulated on an IBM-XT Personal Computer. Simulation results showed that proper adjustments of controller gains enable the robot to perform successful operations. Further research should focus on developing a guideline for the controller gain design to achieve system stability.

  16. Standardization of exhaled breath condensate (EBC) collection using a feedback regulated breathing pattern (United States)

    Collection of exhaled breath condensate (EBC) fluid by cooling of expired breath is a potentially valuable approach for the detection of biomarkers associated with disease or exposure to xenobiotics. EBC is generally collected using unregulated breathing patterns, perceived to el...

  17. Simulation studies for multichannel active vibration control (United States)

    Prakash, Shashikala; Balasubramaniam, R.; Praseetha, K. K.


    Traditional approach to vibration control uses passive techniques, which are relatively large, costly and ineffective at low frequencies. Active Vibration Control (AVC) is used to overcome these problems & in AVC additional sources (secondary) are used to cancel vibration from primary source based on the principle of superposition theorem Since the characteristics of the vibration source and environment are time varying, the AVC system must be adaptive. Adaptive systems have the ability to track time varying disturbances and provide optimal control over a much broader range of conditions than conventional fixed control systems. In multi channel AVC vibration fields in large dimensions are controlled & is more complicated. Therefore to actively control low frequency vibrations on large structures, multi channel AVC requires a control system that uses multiple secondary sources to control the vibration field simultaneously at multiple error sensor locations. The error criterion that can be directly measured is the sum of squares of outputs of number of sensors. The adaptive algorithm is designed to minimize this & the algorithm implemented is the "Multiple error LMS algorithm." The best known applications of multiple channel FXLMS algorithm is in real time AVC and system identification. More wider applications are in the control of propeller induced noise in flight cabin interiors. In the present paper the results of simulation studies carried out in MATLAB as well as on TMS320C32 DSP processor will be brought out for a two-channel case.

  18. Adaptive Piezoelectric Absorber for Active Vibration Control

    Directory of Open Access Journals (Sweden)

    Sven Herold


    Full Text Available Passive vibration control solutions are often limited to working reliably at one design point. Especially applied to lightweight structures, which tend to have unwanted vibration, active vibration control approaches can outperform passive solutions. To generate dynamic forces in a narrow frequency band, passive single-degree-of-freedom oscillators are frequently used as vibration absorbers and neutralizers. In order to respond to changes in system properties and/or the frequency of excitation forces, in this work, adaptive vibration compensation by a tunable piezoelectric vibration absorber is investigated. A special design containing piezoelectric stack actuators is used to cover a large tuning range for the natural frequency of the adaptive vibration absorber, while also the utilization as an active dynamic inertial mass actuator for active control concepts is possible, which can help to implement a broadband vibration control system. An analytical model is set up to derive general design rules for the system. An absorber prototype is set up and validated experimentally for both use cases of an adaptive vibration absorber and inertial mass actuator. Finally, the adaptive vibration control system is installed and tested with a basic truss structure in the laboratory, using both the possibility to adjust the properties of the absorber and active control.

  19. Active control for performance enhancement of electrically controlled rotor

    Institute of Scientific and Technical Information of China (English)

    Lu Yang; Wang Chao


    Electrically controlled rotor (ECR) system has the potential to enhance the rotor perfor-mance by applying higher harmonic flap inputs. In order to explore the feasibility and effectiveness for ECR performance enhancement using closed-loop control method, firstly, an ECR rotor perfor-mance analysis model based on helicopter flight dynamic model is established, which can reflect the performance characteristics of ECR helicopter at high advance ratio. Based on the simulation platform, an active control method named adaptive T-matrix algorithm is adopted to explore the feasibility and effectiveness for ECR performance enhancement. The simulation results verify the effectiveness of this closed-loop control method. For the sample ECR helicopter, about 3%rotor power reduction is obtained with the optimum 2/rev flap inputs at the advance ratio of 0.34. And through analyzing the distributions of attack of angle and drag in rotor disk, the underlying physical essence of ECR power reduction is cleared. Furthermore, the influence of the key control parameters, including convergence factor and weighting matrix, on the effectiveness of closed-loop control for ECR performance enhancement is explored. Some useful results are summarized, which can be used to direct the future active control law design of ECR performance enhancement.

  20. Effects of diaphragm breathing exercise and feedback breathing exercise on pulmonary function in healthy adults


    Yong, Min-Sik; Lee, Hae-Yong; Lee, Yun-Seob


    [Purpose] The present study investigated effects of diaphragm breathing exercise and feedback breathing exercise on respiratory function. [Subjects and Methods] Thirty-one subjects were randomly assigned to two groups; the feedback breathing exercise group and the maneuver-diaphragm exercise group. The feedback breathing exercise group was asked to breathe with feedback breathing device, and the maneuver-diaphragm exercise group was asked to perform diaphragm respiration. Respiratory function...

  1. Outcome of Breathing Exercise (Pranayam on Spirometric Parameters in Type 2 Diabetic Individuals: a Clinical Study

    Directory of Open Access Journals (Sweden)

    Tiwari S.


    Full Text Available Pranayama aims by carrying the involuntary functions of the respiratory mechanism within human control. The term pranayama has comprised by two words: Prana + Ayama. Prana is the vital force and energy which permeates the whole universe. Prana is novel subtle than air and can be defined as the energy essence that is within everything in the universe. In present time emphasis is on the beneficial effects of Pranayam in various diseases i.e. diabetes mellitus, hypertension, obesity and depression by application of specific exercise like walking in a planned way. This was also explained and proved by American college of sport medicine. In Ayurveda various breathing exercise and yogic practices have been mentioned. The respiratory System, central nervous system and cardiovascular system are the important systems which are mostly affected by Pranayam and other physical activities. Breathing exercise is highly effective in endorsement of respiratory system management of diseases related to respiratory system.

  2. Smart actuators for active vibration control (United States)

    Pourboghrat, Farzad; Daneshdoost, Morteza


    In this paper, the design and implementation of smart actuators for active vibration control of mechanical systems are considered. A smart actuator is composed of one or several layers of piezo-electric materials which work both as sensors and actuators. Such a system also includes micro- electronic or power electronic amplifiers, depending on the power requirements and applications, as well as digital signal processing systems for digital control implementation. In addition, PWM type micro/power amplifiers are used for control implementation. Such amplifiers utilize electronic switching components that allow for miniaturization, thermal efficiency, cost reduction, and precision controls that are robust to disturbances and modeling errors. An adaptive control strategy is then developed for vibration damping and motion control of cantilever beams using the proposed smart self-sensing actuators.

  3. Active control of ionized boundary layers

    CERN Document Server

    Mendes, R V


    The challenging problems, in the field of control of chaos or of transition to chaos, lie in the domain of infinite-dimensional systems. Access to all variables being impossible in this case and the controlling action being limited to a few collective variables, it will not in general be possible to drive the whole system to the desired behaviour. A paradigmatic problem of this type is the control of the transition to turbulence in the boundary layer of fluid motion. By analysing a boundary layer flow for an ionized fluid near an airfoil, one concludes that active control of the transition amounts to the resolution of an generalized integro-differential eigenvalue problem. To cope with the required response times and phase accuracy, electromagnetic control, whenever possible, seems more appropriate than mechanical control by microactuators.

  4. The Ins and Outs of Breath Holding: Simple Demonstrations of Complex Respiratory Physiology (United States)

    Skow, Rachel J.; Day, Trevor A.; Fuller, Jonathan E.; Bruce, Christina D.; Steinback, Craig D.


    The physiology of breath holding is complex, and voluntary breath-hold duration is affected by many factors, including practice, psychology, respiratory chemoreflexes, and lung stretch. In this activity, we outline a number of simple laboratory activities or classroom demonstrations that illustrate the complexity of the integrative physiology…

  5. Patients With Respiratory Department of Internal Medicinein Breathing in Sleep Quality Control%呼吸内科患者在睡眠中的呼吸质量控制

    Institute of Scientific and Technical Information of China (English)



    Objective For patients with respiratory problems in the clinical medical treatment of sleep control management, analyze the clinical manifestations of patients with sleep.Methods Adopting Pittsburgh PSQI index measurement analysis in patients with sleep breathing quality change, study of clinical respiratory medicine patients sleep quality. ResultsResults show that the degree of patients' sleep and sleep index problem such as chest pain, cough, dyspnea, has nothing to do with gender, occupation. Conclusion Patients with respiratory medicine in breathing during sleep quality, can realize the clinical intervention in patients with sleep, improve the sleep quality of patients.%目的:临床内科中有呼吸问题的患者进行睡眠治疗控制管理,分析患者睡眠的临床表现。方法采用匹兹堡PSQI睡眠指数测量方法分析患者的呼吸质量变化,研究临床呼吸内科患者的睡眠质量。结果睡眠指数的结果表明患者睡眠的程度与胸痛、咳嗽、呼吸困难等问题有关系,与性别、职业无关。结论呼吸系统内科患者在睡眠中的呼吸质量检测,实现了临床干预患者的睡眠,提高了患者的睡眠质量。

  6. Control of abdominal and expiratory intercostal muscle activity during vomiting - Role of ventral respiratory group expiratory neurons (United States)

    Miller, Alan D.; Tan, L. K.; Suzuki, Ichiro


    The role of ventral respiratory group (VRG) expiratory (E) neurons in the control of abdominal and internal intercostal muscle activity during vomiting was investigated in cats. Two series of experiments were performed: in one, the activity of VRG E neurons was recorded during fictive vomiting in cats that were decerebrated, paralyzed, and artificially ventilated; in the second, the abdominal muscle activity during vomiting was compared before and after sectioning the axons of descending VRG E neurons in decerebrate spontaneously breathing cats. The results show that about two-thirds of VRG E neurons that project at least as far caudally as the lower thoracic cord contribute to internal intercostal muscle activity during vomiting. The remaining VRG E neurons contribute to abdominal muscle activation. As shown by severing the axons of the VRG E neurons, other, as yet unidenified, inputs (either descending from the brain stem or arising from spinal reflexes) can also produce abdominal muscle activation.

  7. Active disturbance rejection controller for chemical reactor

    Energy Technology Data Exchange (ETDEWEB)

    Both, Roxana; Dulf, Eva H.; Muresan, Cristina I., E-mail: [Technical University of Cluj-Napoca, 400114 Cluj-Napoca (Romania)


    In the petrochemical industry, the synthesis of 2 ethyl-hexanol-oxo-alcohols (plasticizers alcohol) is of high importance, being achieved through hydrogenation of 2 ethyl-hexenal inside catalytic trickle bed three-phase reactors. For this type of processes the use of advanced control strategies is suitable due to their nonlinear behavior and extreme sensitivity to load changes and other disturbances. Due to the complexity of the mathematical model an approach was to use a simple linear model of the process in combination with an advanced control algorithm which takes into account the model uncertainties, the disturbances and command signal limitations like robust control. However the resulting controller is complex, involving cost effective hardware. This paper proposes a simple integer-order control scheme using a linear model of the process, based on active disturbance rejection method. By treating the model dynamics as a common disturbance and actively rejecting it, active disturbance rejection control (ADRC) can achieve the desired response. Simulation results are provided to demonstrate the effectiveness of the proposed method.

  8. Active steering control strategy for articulated vehicles

    Institute of Scientific and Technical Information of China (English)

    Kyong-il KIM; Hsin GUAN; Bo WANG; Rui GUO; Fan LIANG


    To improve maneuverability and stability of articulated vehicles, we design an active steering controller, including tractor and trailer controllers, based on linear quadratic regulator (LQR) theory. First, a three-degree-of-freedom (3-DOF) model of the tractor-trailer with steered trailer axles is built. The simulated annealing particle swarm optimization (SAPSO) algorithm is applied to identify the key parameters of the model under specified vehicle speed and steering wheel angle. Thus, the key pa-rameters of the simplified model can be obtained according to the vehicle conditions using an online look-up table and interpola-tion. Simulation results show that vehicle parameter outputs of the simplified model and TruckSim agree well, thus providing the ideal reference yaw rate for the controller. Then the active steering controller of the tractor and trailer based on LQR is designed to follow the desired yaw rate and minimize their side-slip angle of the center of gravity (CG) at the same time. Finally, simulation tests at both low speed and high speed are conducted based on the TruckSim-Simulink program. The results show significant effects on the active steering controller on improving maneuverability at low speed and lateral stability at high speed for the articulated vehicle. The control strategy is applicable for steering not only along gentle curves but also along sharp curves.

  9. Active fault diagnosis by controller modification

    DEFF Research Database (Denmark)

    Stoustrup, Jakob; Niemann, Hans Henrik


    Two active fault diagnosis methods for additive or parametric faults are proposed. Both methods are based on controller reconfiguration rather than on requiring an exogenous excitation signal, as it is otherwise common in active fault diagnosis. For the first method, it is assumed that the system...... in a way that guarantees the continuity of transition and global stability using a recent result on observer parameterization. An illustrative example inspired by a field study of a drag racing vehicle is given. For the second method, an active fault diagnosis method for parametric faults is proposed...

  10. Breathing during REM and non-REM sleep: correlated versus uncorrelated behaviour (United States)

    Kantelhardt, Jan W.; Penzel, Thomas; Rostig, Sven; Becker, Heinrich F.; Havlin, Shlomo; Bunde, Armin


    Healthy sleep can be characterized by several stages: deep sleep, light sleep, and REM sleep. Here we show that these sleep stages lead to different autonomic regulation of breathing. Using the detrended fluctuation analysis up to the fourth order we find that breath-to-breath intervals and breath volumes separated by several breaths are long-range correlated during the REM stages and during wake states. In contrast, in the non-REM stages (deep sleep and light sleep), long-range correlations are absent. This behaviour is very similar to the correlation behaviour of the heart rate during the night and may be related to the phase synchronization between heartbeat and breathing found recently. We speculate that the differences are caused by different cortically influenced control of the autonomic nervous system.

  11. Controller modification applied for active fault detection

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik; Stoustrup, Jakob; Poulsen, Niels Kjølstad


    This paper is focusing on active fault detection (AFD) for parametric faults in closed-loop systems. This auxiliary input applied for the fault detection will also disturb the external output and consequently reduce the performance of the controller. Therefore, only small auxiliary inputs are used...

  12. Active Noise Control for Dishwasher noise (United States)

    Lee, Nokhaeng; Park, Youngjin


    The dishwasher is a useful home appliance and continually used for automatically washing dishes. It's commonly placed in the kitchen with built-in style for practicality and better use of space. In this environment, people are easily exposed to dishwasher noise, so it is an important issue for the consumers, especially for the people living in open and narrow space. Recently, the sound power levels of the noise are about 40 - 50 dBA. It could be achieved by removal of noise sources and passive means of insulating acoustical path. For more reduction, such a quiet mode with the lower speed of cycle has been introduced, but this deteriorates the washing capacity. Under this background, we propose active noise control for dishwasher noise. It is observed that the noise is propagating mainly from the lower part of the front side. Control speakers are placed in the part for the collocation. Observation part of estimating sound field distribution and control part of generating the anti-noise are designed for active noise control. Simulation result shows proposed active noise control scheme could have a potential application for dishwasher noise reduction.

  13. Taking a deep breath

    Directory of Open Access Journals (Sweden)

    Carlos Renato Zacharias


    be paid to language revision and reference citation. Together with its authors and readers, IJHDR contributes to the development of a kind of knowledge close to the borders of science. Therefore, to establish a valid scientific background, the articles must be clearly written, and based on sound assumptions. High-visibility for articles is a fundamental aspect desired by all authors. As an open and free access journal, IJHDR meets that condition, and we are planning to make our influence and visibility even wider. Inclusion in the major databases has paramount importance in the academic milieu, however, it should be considered as a consequence, rather than a goal. In 2013, IJHDR will chair a collaborative project with several research institutions aiming to deliver information everywhere, increasing the visibility of the published articles. Thus, now it is the time to take a deep breath, relax, and prepare you for the forthcoming work! See you in 2013!

  14. System of Optoelectronic Sensors for Breath Analysis

    Directory of Open Access Journals (Sweden)

    Mikołajczyk Janusz


    Full Text Available The paper describes an integrated laser absorption system as a potential tool for breath analysis for clinical diagnostics, online therapy monitoring and metabolic disorder control. The sensors operate basing on cavity enhanced spectroscopy and multi-pass spectroscopy supported by wavelength modulation spectroscopy. The aspects concerning selection of operational spectral range and minimization of interference are also discussed. Tests results of the constructed devices collected with reference samples of biomarkers are also presented. The obtained data provide an opportunity to analyse applicability of optoelectronic sensors in medical screening.

  15. Active control of multiple resistive wall modes (United States)

    Brunsell, P. R.; Yadikin, D.; Gregoratto, D.; Paccagnella, R.; Liu, Y. Q.; Bolzonella, T.; Cecconello, M.; Drake, J. R.; Kuldkepp, M.; Manduchi, G.; Marchiori, G.; Marrelli, L.; Martin, P.; Menmuir, S.; Ortolani, S.; Rachlew, E.; Spizzo, G.; Zanca, P.


    A two-dimensional array of saddle coils at Mc poloidal and Nc toroidal positions is used on the EXTRAP T2R reversed-field pinch (Brunsell P R et al 2001 Plasma Phys. Control. Fusion 43 1457) to study active control of resistive wall modes (RWMs). Spontaneous growth of several RWMs with poloidal mode number m = 1 and different toroidal mode number n is observed experimentally, in agreement with linear MHD modelling. The measured plasma response to a controlled coil field and the plasma response computed using the linear circular cylinder MHD model are in quantitive agreement. Feedback control introduces a linear coupling of modes with toroidal mode numbers n, n' that fulfil the condition |n - n'| = Nc. Pairs of coupled unstable RWMs are present in feedback experiments with an array of Mc × Nc = 4 × 16 coils. Using intelligent shell feedback, the coupled modes are generally not controlled even though the field is suppressed at the active coils. A better suppression of coupled modes may be achieved in the case of rotating modes by using the mode control feedback scheme with individually set complex gains. In feedback with a larger array of Mc × Nc = 4 × 32 coils, the coupling effect largely disappears, and with this array, the main internal RWMs n = -11, -10, +5, +6 are all simultaneously suppressed throughout the discharge (7 8 wall times). With feedback there is a two-fold extension of the pulse length, compared to discharges without feedback.

  16. Control Systems Cyber Security Standards Support Activities

    Energy Technology Data Exchange (ETDEWEB)

    Robert Evans


    The Department of Homeland Security’s Control Systems Security Program (CSSP) is working with industry to secure critical infrastructure sectors from cyber intrusions that could compromise control systems. This document describes CSSP’s current activities with industry organizations in developing cyber security standards for control systems. In addition, it summarizes the standards work being conducted by organizations within the sector and provides a brief listing of sector meetings and conferences that might be of interest for each sector. Control systems cyber security standards are part of a rapidly changing environment. The participation of CSSP in the development effort for these standards has provided consistency in the technical content of the standards while ensuring that information developed by CSSP is included.

  17. Active vibration control of nonlinear benchmark buildings

    Institute of Scientific and Technical Information of China (English)

    ZHOU Xing-de; CHEN Dao-zheng


    The present nonlinear model reduction methods unfit the nonlinear benchmark buildings as their vibration equations belong to a non-affine system. Meanwhile,the controllers designed directly by the nonlinear control strategy have a high order, and they are difficult to be applied actually. Therefore, a new active vibration control way which fits the nonlinear buildings is proposed. The idea of the proposed way is based on the model identification and structural model linearization, and exerting the control force to the built model according to the force action principle. This proposed way has a better practicability as the built model can be reduced by the balance reduction method based on the empirical Grammian matrix. A three-story benchmark structure is presented and the simulation results illustrate that the proposed method is viable for the civil engineering structures.

  18. Dynamic Discontinuous Control for Active Control of Mechanical Vibrations

    Directory of Open Access Journals (Sweden)

    Orestes Llanes Santiago


    Full Text Available This article shows the use of the discontinuous control using dynamic sliding modes for the active isolation of vibrations in mechanical systems. This type of control law constitutes a robust feedback control policy due to its insensitivity to external disturbance inputs, certain immunity to model parameter variations, within known bounds, and to the ever present modelling errors.  The whole theoretical analysis is applied to a lineal model of two degrees of freedom of the vehicle's suspension where the irregularities of the land represent of direct  way the external interferences to the system . To carry out the isolation an electro-hydraulic operator it is used. Simulations are performed which validate the proposed approach.

  19. Active vibration control using DEAP actuators (United States)

    Sarban, Rahimullah; Jones, Richard W.


    Dielectric electro-active polymer (DEAP) is a new type of smart material, which has the potential to be used to provide effective actuation for a wide range of applications. The properties of DEAP material place it somewhere between those of piezoceramics and shape memory alloys. Of the range of DEAP-based actuators that have been developed those having a cylindrical configuration are among the most promising. This contribution introduces the use of a tubular type DEAP actuator for active vibration control purposes. Initially the DEAP-based tubular actuator to be used in this study, produced by Danfoss PolyPower A/S, is introduced along with the static and dynamic characteristics. Secondly an electromechanical model of the tubular actuator is briefly reviewed and its ability to model the actuator's hysteresis characteristics for a range of periodic input signals at different frequencies demonstrated. The model will be used to provide hysteresis compensation in future vibration isolation studies. Experimental active vibration control using the actuator is then examined, specifically active vibration isolation of a 250 g mass subject to shaker generated 'ground vibration'. An adaptive feedforward control strategy is used to achieve this. The ability of the tubular actuator to reject both tonal and broadband random vibratory disturbances is then demonstrated.

  20. Breathing detection with a portable impedance measurement system: first measurements. (United States)

    Cordes, Axel; Foussier, Jerome; Leonhardt, Steffen


    For monitoring the health status of individuals, detection of breathing and heart activity is important. From an electrical point of view, it is known that breathing and heart activity change the electrical impedance distribution in the human body over the time due to ventilation (high impedance) and blood shifts (low impedance). Thus, it is possible to detect both important vital parameters by measuring the impedance of the thorax or the region around lung and heart. For some measurement scenarios it is also essential to detect these parameters contactless. For instance, monitoring bus drivers health could help to limit accidents, but directly connected systems limit the drivers free moving space. One measurement technology for measuring the impedance changes in the chest without cables is the magnetic impedance tomography (MIT). This article describes a portable measurement system we developed for this scenario that allows to measure breathing contactless. Furthermore, first measurements with five volunteers were performed and analyzed.

  1. Active control of combustion instabilities in low NO{sub x} gas turbines

    Energy Technology Data Exchange (ETDEWEB)

    Zinn, B.T.; Neumeier, Y. [Georgia Institute of Technology, Atlanta, GA (United States)


    This 3-year research program was initiated in September, 1995, to investigate active control of detrimental combustion instabilities in low NO{sub x} gas turbines (LNGT), which burn natural gas in a lean premixed mode to reduce NO{sub x} emissions. The program will investigate the mechanisms that drive these instabilities. Furthermore, it will study active control systems (ACS) that can effectively prevent the onset of such instabilities and/or reduce their amplitudes to acceptable levels. An understanding of the driving mechanisms will not only guide the development of effective ACS for LNGT but may also lead to combustor design changes (i.e., passive control) that will fully or partially resolve the problem. Initial attempts to stabilize combustors (i.e., chemical rockets) by ACS were reported more than 40 years ago, but were unsuccessful due to lack of adequate sensors, electronics, and actuators for performing the needed control actions. Progress made in recent years in sensor and actuator technology, electronics, and control theory has rekindled interest in developing ACS for unstable combustors. While initial efforts in this area, which focused on active control of instabilities in air breathing combustors, have demonstrated the considerable potential of active control, they have also indicated that more effective observers, controllers, and actuators are needed for practical applications. Considerable progress has been made in the observer and actuator areas by the principal investigators of this program during the past 2 years under an AFOSR program. The developed observer is based upon wavelets theory, and can identify the amplitudes, frequencies, and phases of the five most dominant combustor modes in (virtually) real time. The developed actuator is a fuel injector that uses a novel magneto-strictive material to modulate the fuel flow rate into the combustor.

  2. Bacterial contamination of anesthesia machines’ internal breathing-circuit-systems (United States)

    Spertini, Verena; Borsoi, Livia; Berger, Jutta; Blacky, Alexander; Dieb-Elschahawi, Magda; Assadian, Ojan


    Background: Bacterial contamination of anesthesia breathing machines and their potential hazard for pulmonary infection and cross-infection among anesthetized patients has been an infection control issue since the 1950s. Disposable equipment and bacterial filters have been introduced to minimize this risk. However, the machines’ internal breathing-circuit-system has been considered to be free of micro-organisms without providing adequate data supporting this view. The aim of the study was to investigate if any micro-organisms can be yielded from used internal machines’ breathing-circuit-system. Based on such results objective reprocessing intervals could be defined. Methods: The internal parts of 40 anesthesia machines’ breathing-circuit-system were investigated. Chi-square test and logistic regression analysis were performed. An on-site process observation of the re-processing sequence was conducted. Results: Bacterial growth was found in 17 of 40 machines (43%). No significant difference was ascertained between the contamination and the processing intervals. The most common contaminants retrieved were coagulase negative Staphylococci, aerobe spore forming bacteria and Micrococcus species. In one breathing-circuit-system, Escherichia coli, and in one further Staphylococcus aureus were yielded. Conclusion: Considering the availability of bacterial filters installed on the outlet of the breathing-circuit-systems, the type of bacteria retrieved and the on-site process observation, we conclude that the contamination found is best explained by a lack of adherence to hygienic measures during and after re-processing of the internal breathing-circuit-system. These results support an extension of the re-processing interval of the anesthesia apparatus longer than the manufacturer’s recommendation of one week. However, the importance of adherence to standard hygienic measures during re-processing needs to be emphasized. PMID:22242095

  3. Submarines, Spacecraft, and Exhaled Breath (United States)

    The International Association of Breath Research (IABR) meetings are an eclectic gathering of researchers in the medical, environmental and instrumentation fields; our focus is on human health as assessed by the measurement and interpretation of trace chemicals in human exhaled b...

  4. Does regular massage from late pregnancy to birth decrease maternal pain perception during labour and birth?--A feasibility study to investigate a programme of massage, controlled breathing and visualization, from 36 weeks of pregnancy until birth. (United States)

    Nabb, Mary T Mc; Kimber, Linda; Haines, Anne; McCourt, Christine


    The present study was undertaken to produce a detailed specification of a programme of massage, controlled breathing and visualization performed regularly by birth partners, from 36 weeks gestation and assisted by a trained professional, following hospital admission during labour and birth. As current research on massage interventions for pain relief in labour is poorly characterized, we began by undertaking a feasibility study on an established massage programme [Goldstone LA. Massage as an orthodox medical treatment past and future. Complementary Therapies in Nursing & Midwifery. 2000;6:169-75]. The intervention was designed in light of experimental findings that repeated massage sessions over 14 days increases pain threshold, by an interaction between oxytocin and opioid neurons [Lund I, Yu L-C, Uvnas-Moberg K, Wang J, Yu C, Kurosawa M, et al. Repeated massage-like stimulation induces long-term effects on nociception: contribution of oxytocinergic mechanisms. European Journal of Neuroscience 2002;16:330-8]. A 4 week time-frame was selected to coincide with a physiological increase in maternal pain threshold [Cogan R, Spinnato JA. Pain and Discomfort Thresholds in Late Pregnancy. Pain 1986;27:63-8, Whipple B, Josimovich JB, Komisaruk BR. Sensory thresholds during the antepartum, intrapartum, and postpartum periods. International Journal of Nursing Studies 1990;27(3):213-21, Gintzler AR, Komisaruk BR. Analgesia is produced by uterocervical mechano-stimulation in rats: roles of afferent nerves and implications for analgesia of pregnancy and parturition. Brain Research 1991;566:299-302, Gintzler AR, Liu N-J. The maternal spinal cord: biochemical and physiological correlates of steroid-activated antinociceptive processes. In: Russell JA, Douglas AJ, Windle RJ, Ingram CD, editors., Progress in Brain Research. Volume 133. The Maternal Brain. Neurobiological and Neuroendocrine adaptation and disorders in pregnancy and postpartum. Amsterdam: Elsevier Science, 2001. p. 83

  5. Robust Active Damping Control of LCL Filtered Grid Connected Converter Based Active Disturbance Rejection Control

    DEFF Research Database (Denmark)

    Abdeldjabar, Benrabah; Xu, Dianguo; Wang, Xiongfei;


    This paper deals with the problem of LCL filter resonance in grid connected inverter control. The system equations are reformulated to allow the application of the active disturbance rejection control (ADRC). The resonance, assumed unknown, is treated as a disturbance, then estimated and mitigated....... By using this new robust control, a high level of performance is achieved with a minimum complexity in the controller design, and without any adaptive algorithm. It is demonstrated that the true quality of the control system is obtained by the proposed solution. Furthermore, it is shown that this control...... is robust against parameter variations and disturbances....

  6. Internal Model Based Active Disturbance Rejection Control


    Pan, Jinwen; Wang, Yong


    The basic active disturbance rejection control (BADRC) algorithm with only one order higher extended state observer (ESO) proves to be robust to both internal and external disturbances. An advantage of BADRC is that in many applications it can achieve high disturbance attenuation level without requiring a detailed model of the plant or disturbance. However, this can be regarded as a disadvantage when the disturbance characteristic is known since the BADRC algorithm cannot exploit such informa...

  7. Breath acetone to monitor life style interventions in field conditions: an exploratory study.

    NARCIS (Netherlands)

    Samudrala, D.; Lammers, G.; Mandon, J.B.; Blanchet, Lionel; Schreuder, T.H.A.; Hopman, M.T.E.; Harren, F.J.M.; Tappy, L.; Cristescu, S.M.


    OBJECTIVE: To assess whether breath acetone concentration can be used to monitor the effects of a prolonged physical activity on whole body lipolysis and hepatic ketogenesis in field conditions. METHODS: Twenty-three non-diabetic, 11 type 1 diabetic, and 17 type 2 diabetic subjects provided breath a

  8. The psychobiology of strained breathing and its cardiovascular implications : A functional system review

    NARCIS (Netherlands)

    Fokkema, DS


    Strained breathing is a natural respiratory pattern, with cardiovascular implications. It is associated with social factors, attention, expectation, and anxiety and with defense behavior in animals. An inhibition of active behavior is characteristic. Strained breathing is based on the functional het

  9. [Historical study on traditional Chinese formulations and crude drugs used for bad breath]. (United States)

    Masuda, Megumi; Murata, Kazuya; Matsuda, Hideaki; Honda, Mami; Honda, Shun-Ichi; Tani, Tadato


    Bad breath is a topic of general interest. In this study, the treatment for bad breath in traditional Chinese medicine was reviewed with a special focus on pathologic diagnosis and crude drug prescriptions. It was shown that bad breath developed based on both systemic and local diseases. Some systemic conditions, including nasal, paranasal, pulmonary and digestive diseases, are considered to cause bad breath. The morbid state of a patient with bad breath has been recognized as being based on "heat syndrome" and "Qi-stagnation syndrome." Bad breath based on "heat syndrome" is manifested as thirst and ulceration of the oral cavity, and has been treated with crude drugs such as Coptis rhizome, Scutellaria root and gypsum. One case study reported that bad breath resulting from a dry mouth was treated with byakkokaninjinto, a Kampo formulation containing gypsum. "Qi" is considered to be the vital energy of all life forms including for the functioning of organs and mental and emotional activity. "Qi-stagnation syndrom," referring to the dysfunction of organs, is manifested as psychosomatic symptoms such as irritability, a flushed face and restlessness. Bad breath based on "Qi-stagnation syndrome" has been treated with crude drugs such as Cnidium rhizome, clove and cinnamon bark. Modern dental and medical treatment both accept the participation of psychogenic agents in the development of bad breath. Bad breath also develops based on periodontal and oral diseases. This type of bad breath has been treated with mouth-wash (collutorium) containing Asiasarum root, Angelica dahurica root and Cnidium rhizome. This historical evidence regarding crude drug prescriptions contributes to the development of mouth care products for preventing and treating bad breath.

  10. Active Control of Shear Thickening in Suspensions

    CERN Document Server

    Lin, Neil Y C; Cates, Michael E; Sun, Jin; Cohen, Itai


    Shear thickening, an increase of viscosity with shear rate, is a ubiquitous phenomena in suspended materials that has implications for broad technological applications. Controlling this thickening behavior remains a major challenge and has led to empirical strategies ranging from altering the particle surfaces and shape to modifying the solvent properties. However, none of these methods allow for active control of flow properties during shear itself. Here, we demonstrate that by strategic imposition of a high-frequency and low-amplitude shear perturbation orthogonal to the primary shearing flow, we can largely eradicate shear thickening. The orthogonal shear effectively becomes a regulator for controlling thickening in the suspension, allowing the viscosity to be reduced by up to two decades on demand. In a separate setup, we show that such effects can be induced by simply agitating the sample transversely to the primary shear direction. Overall, the ability of in situ manipulation of shear thickening paves a...

  11. Control of the Free Convection Flow within the Breathing Zone by Confluent Jets for Improved Performance of Personalized Ventilation: Part 1 – Thermal influence

    DEFF Research Database (Denmark)

    Nagano, H.; Bolashikov, Zhecho Dimitrov; Melikov, Arsen Krikor


    supplied controlled air while the assisting outer jet supplied room air. The mixing between the two jets was minimized by control of the shear stress between the two flows. Thus the air of the inner jet was transported upward to the face. In this paper, manikin-based equivalent temperatures were analyzed...

  12. Caffeine in the neonatal period induces long-lasting changes in sleep and breathing in adult rats. (United States)

    Montandon, Gaspard; Horner, Richard L; Kinkead, Richard; Bairam, Aida


    Caffeine is commonly used clinically to treat apnoeas and unstable breathing associated with premature birth. Caffeine antagonizes adenosine receptors and acts as an efficient respiratory stimulant in neonates. Owing to its persistent effects on adenosine receptor expression in the brain, neonatal caffeine administration also has significant effects on maturation of the respiratory control system. However, since adenosine receptors are critically involved in sleep regulation, and sleep also modulates breathing, we tested the hypothesis that neonatal caffeine treatment disrupts regulation of sleep and breathing in the adult rat. Neonatal caffeine treatment (15 mg kg(-1) day(-1)) was administered from postnatal days 3-12. At adulthood (8-10 weeks old), sleep and breathing were measured with a telemetry system and whole-body plethysmography respectively. In adult rats treated with caffeine during the neonatal period, sleep time was reduced, sleep onset latency was increased, and non-rapid eye movement (non-REM) sleep was fragmented compared to controls. Ventilation at rest was higher in caffeine-treated adult rats compared to controls across sleep/wake states. Hypercapnic ventilatory responses were significantly reduced in caffeine-treated rats compared to control rats across sleep/wake states. Additional experiments in adult anaesthetized rats showed that at similar levels of arterial blood gases, phrenic nerve activity was enhanced in caffeine-treated rats. This study demonstrates that administration of caffeine in the neonatal period alters respiratory control system activity in awake and sleeping rats, as well as in the anaesthetized rats, and also has persistent disrupting effects on sleep that are apparent in adult rats.

  13. Acoustic rhinometry in mouth breathing patients: a systematic review

    Directory of Open Access Journals (Sweden)

    Ana Carolina Cardoso de Melo


    Full Text Available INTRODUCTION: When there is a change in the physiological pattern of nasal breathing, mouth breathing may already be present. The diagnosis of mouth breathing is related to nasal patency. One way to access nasal patency is by acoustic rhinometry.OBJECTIVE: To systematically review the effectiveness of acoustic rhinometry for the diagnosis of patients with mouth breathing.METHODS: Electronic databases LILACS, MEDLINE via PubMed and Bireme, SciELO, Web of Science, Scopus, PsycInfo, CINAHL, and Science Direct, from August to December 2013, were consulted. 11,439 articles were found: 30 from LILACS, 54 from MEDLINE via Bireme, 5558 from MEDLINE via PubMed, 11 from SciELO, 2056 from Web of Science, 1734 from Scopus, 13 from PsycInfo, 1108 from CINAHL, and 875 from Science Direct. Of these, two articles were selected.RESULTS: The heterogeneity in the use of equipment and materials for the assessment of respiratory mode in these studies reveals that there is not yet consensus in the assessment and diagnosis of patients with mouth breathing.CONCLUSION: According to the articles, acoustic rhinometry has been used for almost twenty years, but controlled studies attesting to the efficacy of measuring the geometry of nasal cavities for complementary diagnosis of respiratory mode are warranted.

  14. 13[C]-urea breath test as a novel point-of-care biomarker for tuberculosis treatment and diagnosis.

    Directory of Open Access Journals (Sweden)

    Mandeep S Jassal

    Full Text Available BACKGROUND: Pathogen-specific metabolic pathways may be detected by breath tests based on introduction of stable isotopically-labeled substrates and detection of labeled products in exhaled breath using portable infrared spectrometers. METHODOLOGY/PRINCIPAL FINDINGS: We tested whether mycobacterial urease activity could be utilized in such a breath test format as the basis of a novel biomarker and diagnostic for pulmonary TB. Sensitized New-Zealand White Rabbits underwent bronchoscopic infection with either Mycobacterium bovis or Mycobacterium tuberculosis. Rabbits were treated with 25 mg/kg of isoniazid (INH approximately 2 months after infection when significant cavitary lung pathology was present. [(13C] urea was instilled directly into the lungs of intubated rabbits at selected time points, exhaled air samples analyzed, and the kinetics of delta(13CO(2 formation were determined. Samples obtained prior to inoculation served as control samples for background (13CO(2 conversion in the rabbit model. (13CO(2, from metabolic conversion of [(13C]-urea by mycobacterial urease activity, was readily detectable in the exhaled breath of infected rabbits within 15 minutes of administration. Analyses showed a rapid increase in the rate of (13CO(2 formation both early in disease and prior to treatment with INH. Following INH treatment, all evaluable rabbits showed a decrease in the rate of (13CO(2 formation. CONCLUSIONS/SIGNIFICANCE: Urea breath testing may provide a useful diagnostic and biomarker assay for tuberculosis and for treatment response. Future work will test specificity for M. tuberculosis using lung-targeted dry powder inhalation formulations, combined with co-administering oral urease inhibitors together with a saturating oral dose of unlabeled urea, which would prevent the delta(13CO(2 signal from urease-positive gastrointestinal organisms.

  15. Theme and variations: amphibious air-breathing intertidal fishes. (United States)

    Martin, K L


    Over 70 species of intertidal fishes from 12 families breathe air while emerging from water. Amphibious intertidal fishes generally have no specialized air-breathing organ but rely on vascularized mucosae and cutaneous surfaces in air to exchange both oxygen and carbon dioxide. They differ from air-breathing freshwater fishes in morphology, physiology, ecology and behaviour. Air breathing and terrestrial activity are present to varying degrees in intertidal fish species, correlated with the tidal height of their habitat. The gradient of amphibious lifestyle includes passive remainers that stay in the intertidal zone as tides ebb, active emergers that deliberately leave water in response to poor aquatic conditions and highly mobile amphibious skipper fishes that may spend more time out of water than in it. Normal terrestrial activity is usually aerobic and metabolic rates in air and water are similar. Anaerobic metabolism may be employed during forced exercise or when exposed to aquatic hypoxia. Adaptations for amphibious life include reductions in gill surface area, increased reliance on the skin for respiration and ion exchange, high affinity of haemoglobin for oxygen and adjustments to ventilation and metabolism while in air. Intertidal fishes remain close to water and do not travel far terrestrially, and are unlikely to migrate or colonize new habitats at present, although in the past this may have happened. Many fish species spawn in the intertidal zone, including some that do not breathe air, as eggs and embryos that develop in the intertidal zone benefit from tidal air emergence. With air breathing, amphibious intertidal fishes survive in a variable habitat with minimal adjustments to existing structures. Closely related species in different microhabitats provide unique opportunities for comparative studies.

  16. Airflow Characteristics at the Breathing Zone of a Seated Person

    DEFF Research Database (Denmark)

    Bolashikov, Zhecho Dimitrov; Nagano, Hideaki; Melikov, Arsen Krikor;


    . Passive method for control over the airflow characteristics at the breathing zone to increase the amount of clean air in inhalation consisted of a rectangular board (0.63 m x 0.36 m) placed below the table and pressed against the abdominal. It acted as a barrier reducing the convection flow upcoming from...... the lower body. The resultant velocity field at the breathing zone was measured with Particle Image Velocimetry: a dual cavity laser (λ = 532 nm) and two CCD cameras with 35 and 60 mm lenses. Seeding consisting of glycerol droplets (d = 2-3 μm) was added to the total volume supply. The blocking...

  17. Local flow control for active building facades (United States)

    Kaligotla, Srikar; Chen, Wayne; Glauser, Mark


    Existing building facade designs are for a passive and an impermeable shell to prevent migration of outdoor air into the building and to control heat transfers between the exterior environment and the building interior. An active facade that can respond in real time to changing environmental conditions like wind speed and direction, pollutant load, temperature, humidity and light can lower energy use and maximize occupant comfort. With an increased awareness of cost and environmental effects of energy use, cross or natural ventilation has become an attractive method to lower energy use. Separated flow regions around such buildings are undesirable due to high concentration of pollutants, especially if the vents or dynamic windows for cross ventilation are situated in these regions. Outside pollutant load redistribution through vents can be regulated via flow separation control to minimize transport of pollutants into the building. Flow separation has been substantially reduced with the application of intelligent flow control tools developed at Syracuse University for flow around "silo" (turret) like structures. Similar flow control models can be introduced into buildings with cross ventilation for local external flow separation control. Initial experiments will be performed for turbulent flow over a rectangular block (scaled to be a mid-rise building) that has been configured with dynamic vents and unsteady suction actuators in a wind tunnel at various wind speeds.

  18. Sleep-Disordered Breathing in Chronic SCI: A Randomized Controlled Trial of Treatment Impact on Cognition, Quality of Life, and Cardiovascular Disease (United States)


    Randomized Controlled Trial of Treatment Impact on Cognition, Quality of Life, and Cardiovascular Disease PRINCIPAL INVESTIGATOR: Shirin Shafazand...PAP) will improve cognitive impairment, sleep quality, quality of life, and cardiovascular disease (CVD) surrogate measures in persons with chronic

  19. Decreased physical activity and cardiorespiratory fitness in adults with ankylosing spondylitis: a cross-sectional controlled study. (United States)

    O'Dwyer, Tom; O'Shea, Finbar; Wilson, Fiona


    The health benefits of physical activity (PA) in the general population are numerous; however, few studies have measured PA among adults with ankylosing spondylitis (AS). The aims of this study were to: (1) objectively measure the PA levels and cardiorespiratory fitness of adults with AS and compare these to population controls, and (2) examine the relationships between PA, cardiorespiratory function and condition-specific outcomes. This cross-sectional study included participants (>18 years) meeting the modified New York criteria for AS, and matched population controls. Exclusion criteria were the presence of comorbidities limiting PA, or recent changes in medication usage. Participants completed clinical questionnaires assessing disease activity, physical function and quality of life. Tri-axial accelerometers recorded habitual PA over 1 week. Cardiorespiratory fitness was assessed by submaximal treadmill test with breath-by-breath gas analysis and heart rate monitoring. Thirty-nine adults with AS and 39 controls were recruited. The AS group spent significantly less time performing vigorous-intensity PA than controls [mean difference (95 % CI) 1.8 min/day (1.2-2.7)] and performed significantly fewer bouts of health-enhancing PA [1.7 min/day (1.1-2.5)]. The AS group had significantly lower predicted VO(2MAX) than controls [6.0 mL kg(-1) min(-1) (1.8-10.1)]. PA was associated with aerobic capacity. Sedentary time was associated with disease activity and physical function. Adults with AS participate in less health-enhancing PA than population controls. Fewer than half meet PA recommendations, despite exercise being a key component of AS management. Explorations of PA behaviour and strategies to increase PA participation are needed.

  20. FeNO measured at fixed exhalation flow rate during controlled tidal breathing in children from the age of 2 yr

    DEFF Research Database (Denmark)

    Buchvald, F; Bisgaard, H


    it with NO in mixed exhaled air collected in a bag (FeNO [mixed]). Sixty-seven children were studied: 16 school children and 51 children aged 2-5 yr; 14 of the young children were healthy, 22 had asthma treated with regular inhaled budesonide, and 15 had mild episodic wheeze treated with inhaled terbutaline...... as necessary. FeNO (controlled) showed good agreement with FeNO(SBOL) (factor difference 0.7-1.4), whereas FeNO(mixed) showed poor agreement with FeNO(SBOL) (factor difference 0.51-5.37). FeNO(controlled) (mean [95% confidence interval]) was 6 ppb (4-8 ppb) in young children with asthma, 5 ppb (3-7 ppb......) in young children with mild episodic wheeze, and 3 ppb (2-4 ppb) in healthy control subjects (asthma versus control subjects: p = 0.006; episodic wheeze versus control subjects: p = 0.057). FeNO(controlled) increased from 4 ppb (2-7 ppb) to 13 ppb (10-18 ppb) (p

  1. Adaptive backstepping control for an air-breathing hypersonic vehicle with input constraints%吸气式高超声速飞行器输入受限自适应反演控制

    Institute of Scientific and Technical Information of China (English)

    时建明; 王洁; 叶继坤; 邵雷


    The issues of flight control of an air-breathing hypersonic vehicle with constrained inputs and uncertain aerodynamic coefficients were addressed. Based on backstepping procedure, virtual and actual controllers were designed for linearly parameterized form of the vehicle longitudinal motion model. To deal with uncertain parametric coefficients, on-line adaptive bounding learning scheme was selected. Considering input constraints condition, tracking errors were modified by introducing margin filtering terms of designed controllers and executable inputs. Stability analysis was implemented to prove the effectiveness of the proposed method. Reference trajectory tracking simulation results demonstrate the effectiveness of the control law design under wind disturbance.%针对输入受限和气动与推进参数存在不确定时的吸气式高超声速飞行器飞行控制问题,建立了线性参数化形式的纵向运动模型,通过引入控制量与可执行输入之间的差值滤波环节,修正跟踪误差的定义,设计了使闭环系统稳定的反演鲁棒控制器,给出了气动与推进参数向量的有界自适应估计律.轨迹跟踪仿真结果表明,提出的自适应控制方法能够保证阵风干扰情况下飞行器控制的稳定性.

  2. 考虑推进和气动弹性影响的高超飞行器的建模与控制%Modeling and Robust Coupled Control of Air-Breathing Hypersonic Vehicle Considering Propulsion and Aeroelastic Effects

    Institute of Scientific and Technical Information of China (English)

    曲鑫; 李菁菁; 宋勋; 任章


    针对高超声速飞行器飞行的速度和高度跨度大、变化快,飞行动力学特性复杂;模型具有非线性,强耦合及不确定性的特点,建立了考虑推进及弹性影响的纵向模型,并提出了纵向模型的鲁棒协调控制器设计方法.该方法在典型高超声速飞行器几何结构基础上,针对机体/发动机一体化设计布局,结合高超声速气动力学和气动弹性有关理论,建立非线性纵向模型;通过分析模型的不确定性来源,对刚体-弹性耦合系统设计了基于线性二次型调节器的隐式模型跟随鲁棒协调控制器,从而保证飞行器在不确定干扰情况下的闭环系统稳定性.仿真结果表明,本方法所设计的控制器在给定的不确定性范围内具有良好的鲁棒性.%Considering intricate coupling between engine and flight dynamics and complex interaction between flexible and rigid modes, a longitudinal dynamic model for a flexible air-breathing hypersonic vehicle is developed. Unlike conventional aircraft, air-breathing hypersonic vehicles require the propulsion system to be bighly integrated into the airframe.Furthermore, full-scale hypersonic vehicles tend to have very lightweight and flexible structures with low natural frequencies. Therefore, the bending modes are important and affect the amount of airflow entering into the engine, thus influencing the performance of the propulsion system. The equations of motion for the flexible vehicle are derived by using Lagrange ' s equations and capture effect between the pitch and normal accelerations of the vehicle and the structural dynamics. And then, the uneertainties of the longitudinal model are analyzed and a robust coupled controller based on LQR is designed by using implicit model-following method with respect to variations in the vehicle dynamics resulted from fuel consumption. Finally, the simulation results show that the method introduced in this paper is feasible.

  3. Dysfunctional breathing in children with asthma: a rare but relevant comorbidity. (United States)

    de Groot, Eric P; Duiverman, Eric J; Brand, Paul L P


    Hyperventilation and other clinical manifestations of dysfunctional breathing have been reported in childhood, but the prevalence is unknown. In adults, dysfunctional breathing may be a relevant comorbidity in asthma. We aimed to determine the prevalence of dysfunctional breathing in children with asthma and its impact on asthma control. We performed a cross-sectional survey in 203 asthmatic children (aged 5-18 years), using the Nijmegen Questionnaire and the paediatric Asthma Control Questionnaire. Dysfunctional breathing was found in 11 (5.3%) children; more females (eight (12.9%) out of 62) than males (three (2.1%) out 144, p=0.002). There was a dose-dependent relationship between increasing Nijmegen Questionnaire scores (increased risk of dysfunctional breathing) and poorer asthma control. Poor asthma control was more common in patients with dysfunctional breathing (10 (90.9%) out of 11 children) than in children without (65 (32.3%) out of 192 children; OR 19.3, 95% CI 3.14-430.70; pbreathing was higher (median (range) 2.00 (1.50-3.17)) than in children without (0.50 (0.17-1.17); pbreathing in children and adolescents referred to a hospital-based paediatric asthma clinic for severe or difficult-to-control asthma is 5%. The association between dysfunctional breathing and asthma control suggests that this may be a clinically relevant comorbidity in paediatric asthma.

  4. sLORETA intracortical lagged coherence during breath counting in meditation-naïve participants

    Directory of Open Access Journals (Sweden)

    Patricia eMilz


    Full Text Available We investigated brain functional connectivity comparing no-task resting to breath counting (a meditation exercise but given as task without referring to meditation. Functional connectivity computed as EEG coherence between head-surface data suffers from localization ambiguity, reference dependence, and overestimation due to volume conduction. Lagged coherence between intracortical model sources addresses these criticisms. With this analysis approach, experienced meditators reportedly showed reduced coherence during meditation, meditation-naïve participants have not yet been investigated. 58-channel EEG from 23 healthy, right-handed, meditation-naïve males during resting [3 runs] and breath counting [2 runs] was computed into sLORETA time series of intracortical electrical activity in 19 regions of interest corresponding to the cortex underlying 19 scalp electrode sites, for each of the 8 independent EEG frequency bands covering 1.5-44 Hz. Intracortical lagged coherences and head-surface conventional coherences were computed between the 19 regions/sites. During breath counting compared to resting, paired t-tests corrected for multiple testing revealed 4 significantly lower intracortical lagged coherences, but 4 significantly higher head-surface conventional coherences. Lowered intracortical lagged coherences involved left BA 10 and right BAs 3, 10, 17, 40. In conclusion, intracortical lagged coherence can yield results that are inverted to those of head-surface conventional coherence. The lowered functional connectivity between cognitive control areas and sensory perception areas during meditation-type breath counting compared to resting conceivably reflects the attention to a bodily percept without cognitive reasoning. The reductions in functional connectivity were similar but not as widespread as the reductions reported during meditation in experienced meditators.

  5. Modeling of the expiratory flow pattern of spontaneously breathing cats

    NARCIS (Netherlands)

    Walraven, D; van der Grinten, CPM; Bogaard, JM; van der Ent, CK; Luijendijk, SCM


    A mathematical model was developed describing the entire expiratory flow pattern during spontaneous, tidal breathing in the absence of expiratory muscle activity. It provides estimates for the time constants of the respiratory System (tauRS(model)) and of the decay of continuing inspiratory muscle a

  6. Active Control of Long Bridges Using Flaps

    DEFF Research Database (Denmark)

    Hansen, H. I.; Thoft-Christensen, Palle

    The main problem in designing ultra-long span suspension bridges is flutter. A solution to this problem might be to introduce an active flap control system to increase the flutter wind velocity. The investigated flap control system consists of flaps integrated in the bridge girder so each flap...... is the streamlined part of the edge of the girder. Additional aerodynamic derivatives are shown for the flaps and it is shown how methods already developed can be used to estimate the flutter wind velocity for a bridge section with flaps. As an example, the flutter wind velocity is calculated for different flap...... configurations for a bridge section model by using aerodynamic derivatives for a flat plate. The example shows that different flap configurations can either increase or decrease the flutter wind velocity. for optimal flap configurations flutter will not occur....

  7. Control concepts for active magnetic bearings (United States)

    Siegwart, Roland; Vischer, D.; Larsonneur, R.; Herzog, R.; Traxler, Alfons; Bleuler, H.; Schweitzer, G.


    Active Magnetic Bearings (AMB) are becoming increasingly significant for various industrial applications. Examples are turbo-compressors, centrifuges, high speed milling and grinding spindles, vibration isolation, linear guides, magnetically levitated trains, vacuum and space applications. Thanks to the rapid progress and drastic cost reduction in power- and micro-electronics, the number of AMB applications is growing very rapidly. Industrial uses of AMBs leads to new requirements for AMB-actuators, sensor systems, and rotor dynamics. Especially desirable are new and better control concepts to meet demand such as low cost AMB, high stiffness, high performance, high robustness, high damping up to several kHz, vibration isolation, force-free rotation, and unbalance cancellation. This paper surveys various control concepts for AMBs and discusses their advantages and disadvantages. Theoretical and experimental results are presented.

  8. Coordinated Voltage Control of Active Distribution Network

    Directory of Open Access Journals (Sweden)

    Xie Jiang


    Full Text Available This paper presents a centralized coordinated voltage control method for active distribution network to solve off-limit problem of voltage after incorporation of distributed generation (DG. The proposed method consists of two parts, it coordinated primal-dual interior point method-based voltage regulation schemes of DG reactive powers and capacitors with centralized on-load tap changer (OLTC controlling method which utilizes system’s maximum and minimum voltages, to improve the qualified rate of voltage and reduce the operation numbers of OLTC. The proposed coordination has considered the cost of capacitors. The method is tested using a radial edited IEEE-33 nodes distribution network which is modelled using MATLAB.

  9. [Stahl, Leibniz, Hoffmann and breathing]. (United States)

    Carvallo, Sarah


    At the beginning of the XVIII th century, Wilhelm Gottfried Leibniz and Friedrich Hoffmann criticize Georg Ernst Stahl's medical theory. They differenciate between unsound and true reasonings. Namely, they validate Stahl's definition of breath but extracting it from its animist basis and placing it in an epistemology obeying to the principle of sufficient reason and to the mechanical model. The stahlian discovery consists in understanding breath as a calorific ventilation against the ancient conception; the iatromechanists recognize its accuracy, but they try then to transpose it to a mechanical model of ventilation. Using it in a different epistemological context implies that they analyze the idea of discovery "true" in its contents, but "wrong" in its hypothesis. It impels to examine the epistemology of medical knowledge, as science and therapeutics, and in its links with the other scientific theories. Thus, if Leibniz as philosopher and Hoffmann as doctor consider Stahl's animism so important, it is because its discoveries question the fundamental principles of medicine.

  10. Actively-controlled Beds for Ambulances

    Institute of Scientific and Technical Information of China (English)

    Takahiko Ono; Hikaru Inooka


    During transportation by ambulance,a patient is exposed to inertial acceleration when an ambulance decelerates or turns a corner.Such acceleration often gives a patient physical stress such as blood pressure variation or body sway,which causes strong pain,feeling of discomfort or sometimes critical damage for seriously injured persons.To reduce this undesirable effect of the acceleration,the authors developed the actively-controlled bed (ACB) which controls the posture of a stretcher in real time to reduce foot-to-head and lateral acceleration acting on a supine person.This paper describes development of the ACB,including control system design and performance evaluation.The control system is designed by Zakian's framework,which comprises the principle of matching and the method of inequalities,so that the design specifications on the tracking error and the motor torque are satisfied.From the results of driving experiments and simulation,it is estimated that the ACB can reduce the acceleration acting on a patient by 65% in the foot-to-head direction and by 75% in the lateral direction.

  11. Active Displacement Control of Active Magnetic Bearing System

    Directory of Open Access Journals (Sweden)

    Kertész Milan


    Full Text Available The worldwide energy production nowadays is over 3400 GW while storage systems have a capacity of only 90 GW [1]. There is a good solution for additional storage capacity in flywheel energy storage systems (FES. The main advantage of FES is its relatively high efficiency especially with using the active magnetic bearing system. Therefore there exist good reasons for appropriate simulations and for creating a suitable magneto-structural control system. The magnetic bearing, including actuation, is simulated in the ANSYS parametric design language (APDL. APDL is used to create the loops of transient simulations where boundary conditions (BC are updated based upon a “gap sensor” which controls the nodal position values of the centroid of the shaft and the current density inputs onto the copper windings.

  12. Active Displacement Control of Active Magnetic Bearing System (United States)

    Kertész, Milan; Kozakovič, Radko; Magdolen, Luboš; Masaryk, Michal


    The worldwide energy production nowadays is over 3400 GW while storage systems have a capacity of only 90 GW [1]. There is a good solution for additional storage capacity in flywheel energy storage systems (FES). The main advantage of FES is its relatively high efficiency especially with using the active magnetic bearing system. Therefore there exist good reasons for appropriate simulations and for creating a suitable magneto-structural control system. The magnetic bearing, including actuation, is simulated in the ANSYS parametric design language (APDL). APDL is used to create the loops of transient simulations where boundary conditions (BC) are updated based upon a "gap sensor" which controls the nodal position values of the centroid of the shaft and the current density inputs onto the copper windings.

  13. Active noise control technology. Active soon seigyo gijutsu

    Energy Technology Data Exchange (ETDEWEB)

    Eguchi, M.; Kokubo, F.; Tanaka, S.; Yao, K. (Sharp Corp., Osaka (Japan))


    The signal processing method of the Active Noise Control (ANC) system was studied. The principle of ANC is to output secondary sound waves having opposite phase, identical amplitude from the control point of the sound wave of the primary sound source, and eliminate the noise by interference. As application fields, there are air conditioner ducts and compressors as one dimensional noise source, and automobile and axial fan as three dimensional noise source. In order to improve the stability of coefficient renewal algorithm of Adaptive Digital Filter (ADF), for generation of opposite phase noise, DC-LMS algorithm which can control the rise in gain of specified frequency zone was proposed. Furthermore, with the purpose of reducing the amount of operation, the introduction of lattice type AR filter was tested for the stability of the filter in IIR-ADF (Infinite Impulse Response Adaptive Digital Filter) and its application process. The applicability studies of these improved methods on the noise inside of ducts were actually measured, and the effect was verified. For the multi-channel control of 3 dimensional noise source, reference scanning method to reduce the filter operation was proposed. In the partial space noise eliminating experiment, it was made clear that it possesses equivalent effect to error scanning method. 11 refs., 14 figs., 1 tab.

  14. Effects of diaphragm breathing exercise and feedback breathing exercise on pulmonary function in healthy adults. (United States)

    Yong, Min-Sik; Lee, Hae-Yong; Lee, Yun-Seob


    [Purpose] The present study investigated effects of diaphragm breathing exercise and feedback breathing exercise on respiratory function. [Subjects and Methods] Thirty-one subjects were randomly assigned to two groups; the feedback breathing exercise group and the maneuver-diaphragm exercise group. The feedback breathing exercise group was asked to breathe with feedback breathing device, and the maneuver-diaphragm exercise group was asked to perform diaphragm respiration. Respiratory function was evaluated when a subject sat on a chair comfortably. [Results] There was a significant difference in the functional vital capacity and slow vital capacity before and after all breathing exercises. There was a significant between-group difference in functional vital capacity. However, no between-group difference was found in slow vital capacity. [Conclusion] Diaphragm breathing exercise and feedback breathing exercise can affect respiratory function.

  15. Breathing Modes in Dusty Plasma

    Institute of Scientific and Technical Information of China (English)

    王晓钢; 王爽; 潘秋惠; 刘悦; 贺明峰


    Acoustic breathing modes of dusty plasmas have been investigated in a cylindricalsystem with an axial symmetry. The linear wave solution and a "dispersion" relation were derived.It was found that in an infinite area, the mode is reduced to a "classical" dust acoustic wave inthe region away from the center. If the dusty plasma is confined in a finite region, however, thebreathing (or heart-beating) behavior would be found as observed in many experiments.

  16. Tracking, Analysis and Sonification of Movement and Breathing for Supporting Physical Activity in Chronic Pain Using The Go-with-the-flow Framework

    Directory of Open Access Journals (Sweden)

    Aneesha Singh


    Our studies show that a self-defined SES calibrated to individual psychological needs helps to increase awareness, motivation, performance and relaxation in physical activity and can support people to gain confidence in activity and transfer gains to their everyday lives. This approach could be useful in other chronic conditions where progress in physical activity rehabilitation and self-management is undermined by anxiety about physical vulnerability.

  17. Running and Breathing in Mammals (United States)

    Bramble, Dennis M.; Carrier, David R.


    Mechanical constraints appear to require that locomotion and breathing be synchronized in running mammals. Phase locking of limb and respiratory frequency has now been recorded during treadmill running in jackrabbits and during locomotion on solid ground in dogs, horses, and humans. Quadrupedal species normally synchronize the locomotor and respiratory cycles at a constant ratio of 1:1 (strides per breath) in both the trot and gallop. Human runners differ from quadrupeds in that while running they employ several phase-locked patterns (4:1, 3:1, 2:1, 1:1, 5:2, and 3:2), although a 2:1 coupling ratio appears to be favored. Even though the evolution of bipedal gait has reduced the mechanical constraints on respiration in man, thereby permitting greater flexibility in breathing pattern, it has seemingly not eliminated the need for the synchronization of respiration and body motion during sustained running. Flying birds have independently achieved phase-locked locomotor and respiratory cycles. This hints that strict locomotor-respiratory coupling may be a vital factor in the sustained aerobic exercise of endothermic vertebrates, especially those in which the stresses of locomotion tend to deform the thoracic complex.

  18. Real Time Vibration Control of Active Suspension System with Active Force Control using Iterative Learning Algorithm

    Directory of Open Access Journals (Sweden)



    Full Text Available This paper presents concurrent vibration control of a laboratory scaled vibration isolator platform with Active Force Control (AFC using Iterative Learning Algorithm (ILA. The work investigates the performance of the traditional Proportional Integral Derivative Controller (PIDC with and without AFC using ILA for vibration suppression. The physical single degree of freedom quarter car has been interfaced with a personal computer using a National Instruments data acquisition card NI USB 6008. The controllers are designed and simulated using LabVIEW simulation software. The results infer that the PIDC with AFC using ILA works superior than the PIDC.

  19. SU-F-BRB-03: Quantifying Patient Motion During Deep-Inspiration Breath-Hold Using the ABC System with Simultaneous Surface Photogrammetry

    Energy Technology Data Exchange (ETDEWEB)

    Cheung, Y; Rahimi, A; Sawant, A [UT Southwestern Medical Center, Dallas, TX (United States)


    Purpose: Active breathing control (ABC) has been used to reduce treatment margin due to respiratory organ motion by enforcing temporary breath-holds. However, in practice, even if the ABC device indicates constant lung volume during breath-hold, the patient may still exhibit minor chest motion. Consequently, therapists are given a false sense of security that the patient is immobilized. This study aims at quantifying such motion during ABC breath-holds by monitoring the patient chest motion using a surface photogrammetry system, VisionRT. Methods: A female patient with breast cancer was selected to evaluate chest motion during ABC breath-holds. During the entire course of treatment, the patient’s chest surface was monitored by a surface photogrammetry system, VisionRT. Specifically, a user-defined region-of-interest (ROI) on the chest surface was selected for the system to track at a rate of ∼3Hz. The surface motion was estimated by rigid image registration between the current ROI image captured and a reference image. The translational and rotational displacements computed were saved in a log file. Results: A total of 20 fractions of radiation treatment were monitored by VisionRT. After removing noisy data, we obtained chest motion of 79 breath-hold sessions. Mean chest motion in AP direction during breath-holds is 1.31mm with 0.62mm standard deviation. Of the 79 sessions, the patient exhibited motion ranging from 0–1 mm (30 sessions), 1–2 mm (37 sessions), 2–3 mm (11 sessions) and >3 mm (1 session). Conclusion: Contrary to popular assumptions, the patient is not completely still during ABC breath-hold sessions. In this particular case studied, the patient exhibited chest motion over 2mm in 14 out of 79 breath-holds. Underestimating treatment margin for radiation therapy with ABC could reduce treatment effectiveness due to geometric miss or overdose of critical organs. The senior author receives research funding from NIH, VisionRT, Varian Medical Systems

  20. Satellite cascade attitude control via fuzzy PD controller with active force control under momentum dumping (United States)

    Ismail, Z.; Varatharajoo, R.


    In this paper, fuzzy proportional-derivative (PD) controller with active force control (AFC) scheme is studied and employed in the satellite attitude control system equipped with reaction wheels. The momentum dumping is enabled via proportional integral (PI) controller as the system is impractical without momentum dumping control. The attitude controllers are developed together with their governing equations and evaluated through numerical treatment with respect to a reference satellite mission. From the results, it is evident that the three axis attitudes accuracies can be improved up to ±0.001 degree through the fuzzy PD controller with AFC scheme for the attitude control. In addition, the three-axis wheel angular momentums are well maintained during the attitude control tasks.

  1. 吸气式高超声速飞行器纵向运动反演控制器设计%Design of Backstepping Controller for Longitudinal Motion of an Air-Breathing Hypersonic Vehicle

    Institute of Scientific and Technical Information of China (English)

    时建明; 王洁; 王琨; 邵雷


    针对气动/推进/结构耦合的吸气式高超声速飞行器纵向平面飞行控制问题,提出了基于反演的鲁棒控制器设计方法.利用曲线拟合模型将控制系统表示为反馈形式,采用反演方法设计虚拟和实际控制器,并引入鲁棒微分器估计虚拟控制量的导数,解决了虚拟控制量求导运算复杂的问题.为增强控制器应对不确定项的鲁棒性,设计了超扭曲滑模干扰观测器,实现了对系统模型不确定项的估计和补偿.对吸气式高超声速飞行器一体化原理模型的速度和高度指令跟踪仿真表明,该控制器对拟合误差和外加干扰等系统不确定项具有鲁棒性,系统状态量能够在指令跟踪过程中趋于平衡状态,从而验证了所提方案的有效性.%A robust controller based on backstepping design procedure is proposed for an air-breathing hypersonic vehicle with aerodynamic, propulsion and structural couplings. Expressing the control system as strict feedback form via the curve-fitted model, virtual and actual controllers are constructed for the velocity and altitude subsystems. To omit analytic calculation of the virtual control law derivatives, which is very difficult to evaluate in the traditional backstepping control, robust differentiators are introduced. Super-twisting sliding mode disturbance observers are designed to compensate uncertainties in the system dynamics. Trajectory tracking simulation performed on the first principle model of the vehicle's longitudinal dynamics shows that the designed controllers are robust to model fitting errors and outside disturbances, and the system states reach trimmed condition asymptotically.

  2. Analyses of mouse breath with ion mobility spectrometry: a feasibility study. (United States)

    Vautz, Wolfgang; Nolte, Jürgen; Bufe, Albrecht; Baumbach, Jörg I; Peters, Marcus


    Exhaled breath can provide comprehensive information about the metabolic state of the subject. Breath analysis carried out during animal experiments promises to increase the information obtained from a particular experiment significantly. This feasibility study should demonstrate the potential of ion mobility spectrometry for animal breath analysis, even for mice. In the framework of the feasibility study, an ion mobility spectrometer coupled with a multicapillary column for rapid preseparation was used to analyze the breath of orotracheally intubated spontaneously breathing mice during anesthesia for the very first time. The sampling procedure was validated successfully. Furthermore, the breath of four mice (2 healthy control mice, 2 with allergic airway inflammation) was analyzed. Twelve peaks were identified directly by comparison with a database. Additional mass spectrometric analyses were carried out for validation and for identification of unknown signals. Significantly different patterns of metabolites were detected in healthy mice compared with asthmatic mice, thus demonstrating the feasibility of analyzing mouse breath with ion mobility spectrometry. However, further investigations including a higher animal number for validation and identification of unknown signals are needed. Nevertheless, the results of the study demonstrate that the method is capable of rapid analyses of the breath of mice, thus significantly increasing the information obtained from each particular animal experiment.

  3. Suck, swallow and breathing coordination in infants with infantile colic

    Directory of Open Access Journals (Sweden)

    Hanlie Degenaar


    Full Text Available Background: There appears to be a perception amongst parents and in popular literature that infantile colic is caused by feeding difficulties. Limited support for this perception is found in scientific literature. Whilst there is scientific evidence that suck, swallow and breathing are key components of successful feeding, these components and the coordination thereof in infants with colic have not been extensively researched.Objective: The objective of the study was to explore the suck, swallow and breathing coordination in infants with infantile colic and compare it with infants without the condition.Method: An assessment protocol for suck, swallow and breathing coordination was compiled from literature. This protocol was performed on a research group of 50 infants, independently diagnosed with infantile colic, and a control group of 28 infants without the condition. All participants were from two rural towns in the North–West province, South Africa, selected with a snowball selection method and strict selection criteria. The study followed a static comparison group design. Results: A significant difference in the key components of feeding and the presence of colic in participants of four age categories were found. The correlation between postural control and the presence of infantile colic were sustained in participants from 2–19 weeks old. Conclusion: Suck, swallow and breathing were found to be significantly associated with infantile colic. The findings should be investigated further. It appears that speech-language therapists may play an expanding role in infantile colic.[pdf to follow

  4. Prediction control of active power filters

    Institute of Scientific and Technical Information of China (English)

    王莉娜; 罗安


    A prediction method to obtain harmonic reference for active power filter is presented. It is a new use ofthe adaptive predictive filter based on FIR. The delay inherent in digital controller is successfully compensated by u-sing the proposed method, and the computing load is not very large compared with the conventional method. Moreo-ver, no additional hardware is needed. Its DSP-based realization is also presented, which is characterized by time-va-riant rate sampling, quasi synchronous sampling, and synchronous operation among the line frequency, PWM gener-ating and sampling in A/D unit. Synchronous operation releases the limitation on PWM modulation ratio and guar-antees that the electrical noises resulting from the switching operation of IGBTs do not interfere with the sampledcurrent. The simulation and experimental results verify the satisfactory performance of the proposed method.

  5. Mice lacking brain/kidney phosphate-activated glutaminase have impaired glutamatergic synaptic transmission, altered breathing, disorganized goal-directed behavior and die shortly after birth. (United States)

    Masson, Justine; Darmon, Michèle; Conjard, Agnès; Chuhma, Nao; Ropert, Nicole; Thoby-Brisson, Muriel; Foutz, Arthur S; Parrot, Sandrine; Miller, Gretchen M; Jorisch, Renée; Polan, Jonathan; Hamon, Michel; Hen, René; Rayport, Stephen


    Neurotransmitter glutamate has been thought to derive mainly from glutamine via the action of glutaminase type 1 (GLS1). To address the importance of this pathway in glutamatergic transmission, we knocked out GLS1 in mice. The insertion of a STOP cassette by homologous recombination produced a null allele that blocked transcription, encoded no immunoreactive protein, and abolished GLS1 enzymatic activity. Null mutants were slightly smaller, were deficient in goal-directed behavior, hypoventilated, and died in the first postnatal day. No gross or microscopic defects were detected in peripheral organs or in the CNS. In cultured neurons from the null mutants, miniature EPSC amplitude and duration were normal; however, the amplitude of evoked EPSCs decayed more rapidly with sustained 10 Hz stimulation, consistent with an observed reduction in depolarization-evoked glutamate release. Because of this activity-dependent impairment in glutamatergic transmission, we surmised that respiratory networks, which require temporal summation of synaptic input, would be particularly affected. We found that the amplitude of inspirations was decreased in vivo, chemosensitivity to CO2 was severely altered, and the frequency of pacemaker activity recorded in the respiratory generator in the pre-Bötzinger complex, a glutamatergic brainstem network that can be isolated in vitro, was increased. Our results show that although alternate pathways to GLS1 glutamate synthesis support baseline glutamatergic transmission, the GLS1 pathway is essential for maintaining the function of active synapses, and thus the mutation is associated with impaired respiratory function, abnormal goal-directed behavior, and neonatal demise.

  6. Active controlled studies in antibiotic drug development. (United States)

    Dane, Aaron


    The increasing concern of antibacterial resistance has been well documented, as has the relative lack of antibiotic development. This paradox is in part due to challenges with clinical development of antibiotics. Because of their rapid progression, untreated bacterial infections are associated with significant morbidity and mortality. As a consequence, placebo-controlled studies of new agents are unethical. Rather, pivotal development studies are mostly conducted using non-inferiority designs versus an active comparator. Further, infections because of comparator-resistant isolates must usually be excluded from the trial programme. Unfortunately, the placebo-controlled data classically used in support of non-inferiority designs are largely unavailable for antibiotics. The only available data are from the 1930s and 1940s and their use is associated with significant concerns regarding constancy and assay sensitivity. Extended public debate on this challenge has led to proposed solutions by some in which these concerns are addressed by using very conservative approaches to trial design, endpoints and non-inferiority margins, in some cases leading to potentially impractical studies. To compound this challenge, different Regulatory Authorities seem to be taking different approaches to these key issues. If harmonisation does not occur, antibiotic development will become increasingly challenging, with the risk of further decreases in the amount of antibiotic drug development. However with clarity on Regulatory requirements and an ability to feasibly conduct global development programmes, it should be possible to bring much needed additional antibiotics to patients.

  7. Cardiovascular and Respiratory Effect of Yogic Slow Breathing in the Yoga Beginner: What Is the Best Approach?

    Directory of Open Access Journals (Sweden)

    Heather Mason


    Full Text Available Slow breathing increases cardiac-vagal baroreflex sensitivity (BRS, improves oxygen saturation, lowers blood pressure, and reduces anxiety. Within the yoga tradition slow breathing is often paired with a contraction of the glottis muscles. This resistance breath “ujjayi” is performed at various rates and ratios of inspiration/expiration. To test whether ujjayi had additional positive effects to slow breathing, we compared BRS and ventilatory control under different breathing patterns (equal/unequal inspiration/expiration at 6 breath/min, with/without ujjayi, in 17 yoga-naive young healthy participants. BRS increased with slow breathing techniques with or without expiratory ujjayi ( or higher except with inspiratory + expiratory ujjayi. The maximal increase in BRS and decrease in blood pressure were found in slow breathing with equal inspiration and expiration. This corresponded with a significant improvement in oxygen saturation without increase in heart rate and ventilation. Ujjayi showed similar increase in oxygen saturation but slightly lesser improvement in baroreflex sensitivity with no change in blood pressure. The slow breathing with equal inspiration and expiration seems the best technique for improving baroreflex sensitivity in yoga-naive subjects. The effects of ujjayi seems dependent on increased intrathoracic pressure that requires greater effort than normal slow breathing.

  8. [Breath-analysis tests in gastroenetrological diagnosis]. (United States)

    Caspary, W F


    The introduction of a simple method for analysis of 14CO2 in breath allowed a more widely application of breath-tests in the diagnosis of gastroenterological diseases. During a breath-test a 14C-labelled compound is administered orally and 14CO2 is subsequently measured in breath by discontinuous samplings of 14CO2 by virtue of a trapping solution (hyamine hydroxide). Most helpful tests in gastroenterology are the 14C-glycyl-cholate breath test for detecting increased deconjugation of bile acids due to small intestinal bacterial overgrowth or bile acid malabsorption in ileal resection or Crohn's disease of the ileum, the 14C-lactose breath test in lactase deficiency, whereas the 14C-tripalmitin test seems less helpful in the diagnosis of fat malabsorption. A 14C-aminopyrine breath test may turn out to be a simple and valuable liver function test. Oral loading tests with breath analysis of H2 have shown to be helpful in the diagnosis of carbohydrate malabsorption, determination of intestinal transit time and intestinal gas production. Due to technical reasons (gas-chromatographie analysis) H2-breath analysis is still limited to research centers. Despite low radiation doses after oral administration of 14C-labelled compounds oral loading tests with H2- or 13C-analysis might be preferable in the future.

  9. Active control of aerodynamic noise; Active control ni yoru furyoku soon no seigyo

    Energy Technology Data Exchange (ETDEWEB)

    Nishimura, M. [Mitsubishi Heavy Industries, Ltd., Tokyo (Japan)


    This paper introduces summary and examples of active noise control (ANC) and active flow control (AFC) as the aerodynamic noise control techniques. The ANC is a technique to generate noise of a reverse phase which cancels the original noise. Noise reduced especially effectively by the ANC is noise from fans and ducts used for engine air supply and exhaust. The ANC is effective in low frequencies, and when used with a passive method, a compact exhaust silencer can be realized, which has high noise reducing performance over the whole frequency band and has low pressure loss. Signal processing in active noise reduction system is always so adjusted that noise is discharged from a secondary noise source in which signals detected by a detection microphone is given a digital filter treatment, and output from an error microphone is minimized. The AFC has been incapable of realizing a reverse phase over a wide frequency band when depended on analog treatment. However, the authors have developed an adaptive type feedback control system, and verified that the system can be applied to any frequency variation and control it in a stable manner. 15 refs., 9 figs., 1 tab.

  10. Sleep disordered breathing in pregnancy

    Directory of Open Access Journals (Sweden)

    Bilgay Izci Balserak


    Sleep disordered breathing (SDB is very common during pregnancy, and is most likely explained by hormonal, physiological and physical changes. Maternal obesity, one of the major risk factors for SDB, together with physiological changes in pregnancy may predispose women to develop SDB. SDB has been associated with poor maternal and fetal outcomes. Thus, early identification, diagnosis and treatment of SDB are important in pregnancy. This article reviews the pregnancy-related changes affecting the severity of SDB, the epidemiology and the risk factors of SDB in pregnancy, the association of SDB with adverse pregnancy outcomes, and screening and management options specific for this population.

  11. 42 CFR 84.79 - Breathing gas; minimum requirements. (United States)


    ... 42 Public Health 1 2010-10-01 2010-10-01 false Breathing gas; minimum requirements. 84.79 Section...-Contained Breathing Apparatus § 84.79 Breathing gas; minimum requirements. (a) Breathing gas used to supply... respiratory tract irritating compounds. (c) Compressed, gaseous breathing air shall meet the...

  12. 42 CFR 84.72 - Breathing tubes; minimum requirements. (United States)


    ... 42 Public Health 1 2010-10-01 2010-10-01 false Breathing tubes; minimum requirements. 84.72...-Contained Breathing Apparatus § 84.72 Breathing tubes; minimum requirements. Flexible breathing tubes used in conjunction with breathing apparatus shall be designed and constructed to prevent: (a)...

  13. 42 CFR 84.85 - Breathing bags; minimum requirements. (United States)


    ... 42 Public Health 1 2010-10-01 2010-10-01 false Breathing bags; minimum requirements. 84.85 Section...-Contained Breathing Apparatus § 84.85 Breathing bags; minimum requirements. (a) Breathing bags shall have.... (b) Breathing bags shall be constructed of materials which are flexible and resistant to...

  14. News from the Breath Analysis Summit 2011. (United States)

    Corradi, Massimo; Mutti, Antonio


    This special section highlights some of the important work presented at the Breath Analysis Summit 2011, which was held in Parma (Italy) from 11 to 14 September 2011. The meeting, which was jointly organized by the International Association for Breath Research and the University of Parma, was attended by more than 250 delegates from 33 countries, and offered 34 invited lectures and 64 unsolicited scientific contributions. The summit was organized to provide a forum to scientists, engineers and clinicians to present their latest findings and to meet industry executives and entrepreneurs to discuss key trends, future directions and technologies available for breath analysis. A major focus was on nitric oxide, exhaled breath condensate, electronic nose, mass spectrometry and newer sensor technologies. Medical applications ranged from asthma and other respiratory diseases to gastrointestinal disease, occupational diseases, critical care and cancer. Most people identify breath tests with breathalysers used by police to estimate ethanol concentration in blood. However, breath testing has far more sophisticated applications. Breath analysis is rapidly evolving as a new frontier in medical testing for disease states in the lung and beyond. Every individual has a breath fingerprint-or 'breathprint'-that can provide useful information about his or her state of health. This breathprint comprises the many thousands of molecules that are expelled with each breath we exhale. Breath research in the past few years has uncovered the scientific and molecular basis for such clinical observations. Relying on mass spectrometry, we have been able to identify many such unique substances in exhaled breath, including gases, such as nitric oxide (NO) and carbon monoxide (CO), and a wide array of volatile organic compounds. Exhaled breath also carries aerosolized droplets that can be collected as an exhaled breath condensate that contains endogenously produced non-volatile compounds. Breath

  15. Influência do aumento do tempo inspiratório na ventilação pulmonar de pacientes submetidos à ventilação mecânica na modalidade pressão controlada Influence of the breathing time increase in the pulmonary ventilation of patients submitted to mechanical ventilation in controlled pressure mode

    Directory of Open Access Journals (Sweden)

    Datiene Aparecida Diniz Rodrigues Bernal


    Full Text Available JUSTIFICATIVA E OBJETIVOS: O suporte ventilatório mecânico é uma das principais modalidades de apoio usadas em terapia intensiva. Na modalidade de pressão pré-determinada a pressão máxima é regulada, mas o volume corrente (V T é uma função complexa da pressão aplicada e da sua velocidade em alcançar a pressão-alvo, do tempo inspiratório disponível e da resistência à respiração. O objetivo deste trabalho foi avaliar a influência do incremento do tempo inspiratório na ventilação pulmonar. MÉTODO: O estudo foi realizado na UTI Adulto do Hospital Regional de Mato Grosso do Sul em Campo Grande/MS. Foram incluídos pacientes adultos, de ambos os sexos, com idade entre 16 e 84 anos, submetidos à ventilação mecânica no modo pressão controlada ou assistido-controlada. Foi ajustado o tempo inspiratório em 1 seg, incrementando em 0,2 seg até o valor limite de 1,6 seg. Foram avaliados o volume-corrente (V T e o volume-minuto (V E de 13 pacientes nos tempos inspiratórios de 1,0s; 1,2s; 1,4s e 1,6s. RESULTADOS: Nas médias dos V T e V E observou-se um aumento crescente após o incremento do tempo inspiratório. Não foram encontrados na literatura consultada, dados que correlacionassem o tempo inspiratório com alterações no volume-corrente. CONCLUSÕES: O incremento do tempo inspiratório na ventilação por controle de pressão pode ter influência na determinação do volume-corrente ofertado ao paciente.BACKGROUND AND OBJECTIVES: The mechanical ventilator support is one of the main used modalities of support in intensive therapy. In the modality of predetermined pressure, the maximum pressure is regulated, but the current volume (V T is a complex function of the applied pressure and its speed to reach the pressure-target, of the available breathing time and the resistance to the breath. This paper has as objective to evaluate the influences of the increment of the breathing time in the pulmonary ventilation. METHODS: The

  16. Breathing Maneuvers as a Vasoactive Stimulus for Detecting Inducible Myocardial Ischemia – An Experimental Cardiovascular Magnetic Resonance Study (United States)

    Fischer, Kady; Guensch, Dominik P; Shie, Nancy; Lebel, Julie; Friedrich, Matthias G


    Background Breathing maneuvers can elicit a similar vascular response as vasodilatory agents like adenosine; yet, their potential diagnostic utility in the presence of coronary artery stenosis is unknown. The objective of the study is to investigate if breathing maneuvers can non-invasively detect inducible ischemia in an experimental animal model when the myocardium is imaged with oxygenation-sensitive cardiovascular magnetic resonance (OS-CMR). Methods and Findings In 11 anesthetised swine with experimentally induced significant stenosis (fractional flow reserve coronary artery (LAD) and 9 control animals, OS-CMR at 3T was performed during two different breathing maneuvers, a long breath-hold; and a combined maneuver of 60s of hyperventilation followed by a long breath-hold. The resulting change of myocardial oxygenation was compared to the invasive measurements of coronary blood flow, blood gases, and oxygen extraction. In control animals, all breathing maneuvers could significantly alter coronary blood flow as hyperventilation decreased coronary blood flow by 34±23%. A long breath-hold alone led to an increase of 97±88%, while the increase was 346±327% (pcoronary blood flow response was attenuated after both hyperventilation and the following breath-hold. This was matched by the observed oxygenation response as breath-holds following hyperventilation consistently yielded a significant difference in the signal of the MRI images between the perfusion territory of the stenosis LAD and remote myocardium. There was no difference between the coronary territories during the other breathing maneuvers or in the control group at any point. Conclusion In an experimental animal model, the response to a combined breathing maneuver of hyperventilation with subsequent breath-holding is blunted in myocardium subject to significant coronary artery stenosis. This maneuver may allow for detecting severe coronary artery stenosis and have a significant clinical potential as a

  17. System identification and control of the JPL active structure (United States)

    Fanson, J. L.; Lurie, B. J.; O'Brien, J. F.; Chu, C.-C.; Smith, R. S.


    This paper describes recent advances in structural quieting technology as applied to active truss structures intended for high precision space based optics applications. Collocated active damping control loops are designed in order to impedance match piezoelectric active members to the structure. Noncollocated control loops are also studied in relation to controlling lightly damped structures.

  18. Breath markers of oxidative stress in patients with unstable angina. (United States)

    Phillips, Michael; Cataneo, Renee N; Greenberg, Joel; Grodman, Richard; Salazar, Manuel


    Cardiac chest pain is accompanied by oxidative stress, which generates alkanes and other volatile organic compounds (VOCs). These VOCs are excreted in the breath and could potentially provide a rational diagnostic marker of disease. The breath methylated alkane contour (BMAC), a 3-dimensional surface plot of C4-C20 alkanes and monomethylated alkanes, provides a comprehensive set of markers of oxidative stress. In this pilot study, we compared BMACs in patients with unstable angina pectoris and in healthy volunteers. Breath VOCs were analyzed in 30 patients with unstable angina confirmed by coronary angiography and in 38 age-matched healthy volunteers with no known history of heart disease (mean age +/- SD, 62.7 +/- 12.3 years and 62.5 +/- 10.0, not significant). BMACs in both groups were compared to identify the combination of VOCs that provided the best discrimination between the 2 groups. Forward stepwise entry discriminant analysis selected 8 VOCs to construct a predictive model that correctly classified unstable angina patients with sensitivity of 90% (27 of 30) and specificity of 73.7% (28 of 38). On cross-validation, sensitivity was 83.3% (25 of 30) and specificity was 71.1% (27 of 38). We conclude that the breath test distinguished between patients with unstable angina and healthy control subjects.

  19. Breath acidification in adolescent runners exposed to atmospheric pollution: A prospective, repeated measures observational study

    Directory of Open Access Journals (Sweden)

    Van Sickle David


    Full Text Available Abstract Background Vigorous outdoors exercise during an episode of air pollution might cause airway inflammation. The purpose of this study was to examine the effects of vigorous outdoor exercise during peak smog season on breath pH, a biomarker of airway inflammation, in adolescent athletes. Methods We measured breath pH both pre- and post-exercise on ten days during peak smog season in 16 high school athletes engaged in daily long-distance running in a downwind suburb of Atlanta. The association of post-exercise breath pH with ambient ozone and particulate matter concentrations was tested with linear regression. Results We collected 144 pre-exercise and 146 post-exercise breath samples from 16 runners (mean age 14.9 years, 56% male. Median pre-exercise breath pH was 7.58 (interquartile range: 6.90 to 7.86 and did not change significantly after exercise. We observed no significant association between ambient ozone or particulate matter and post-exercise breath pH. However both pre- and post-exercise breath pH were strikingly low in these athletes when compared to a control sample of 14 relatively sedentary healthy adults and to published values of breath pH in healthy subjects. Conclusion Although we did not observe an acute effect of air pollution exposure during exercise on breath pH, breath pH was surprisingly low in this sample of otherwise healthy long-distance runners. We speculate that repetitive vigorous exercise may induce airway acidification.

  20. SU-E-J-185: A Systematic Review of Breathing Guidance in Radiation Oncology and Radiology

    Energy Technology Data Exchange (ETDEWEB)

    Pollock, S; Keall, P [University of Sydney, Sydney (Australia); Keall, R [Hammond Care Palliative and Supportive Care Service, Sydney, NSW (Australia)


    Purpose: The advent of image-guided radiation therapy (IGRT) has led to dramatic improvements in the accuracy of treatment delivery in radiotherapy. Such advancements have highlighted the deleterious impact tumor motion can have on both image quality and radiation treatment delivery. One approach to reducing tumor motion is the use of breathing guidance systems during imaging and treatment. A review of such research had not yet been performed, it was therefore our aim to perform a systematic review of breathing guidance interventions within the fields of radiation oncology and radiology. Methods: Results of online database searches were filtered in accordance to a set of eligibility criteria. The search, filtration, and analysis of articles were conducted in accordance with the PRISMAStatement reporting standard (Preferred Reporting Items for Systematic reviews and Meta-Analyses) utilizing the PICOS approach (Participants, Intervention, Comparison, Outcome, Study design). Participants: Cancer patients, healthy volunteers. Intervention: Biofeedback breathing guidance systems. Comparison: No breathing guidance of the same breathing type. Outcome: Regularity of breathing signal and anatomic/tumor motion, medical image quality, radiation treatment margins and coverage, medical imaging and radiation treatment times. Study design: Quantitative and controlled prospective or retrospective trials. Results: The systematic search yielded a total of 479 articles, which were filtered down to 27 relevant articles in accordance to the eligibility criteria. The vast majority of investigated outcomes were significantly positively impacted by the use of breathing guidance; however, this was dependent upon the nature of the breathing guidance system and study design. In 25/27 studies significant improvements from the use of breathing guidance were observed. Conclusion: The results found here indicate that further clinical studies are warranted which quantify more comprehensively the

  1. Tai Chi Chuan modulates heart rate variability during abdominal breathing in elderly adults. (United States)

    Wei, Gao-Xia; Li, You-Fa; Yue, Xiao-Lin; Ma, Xiao; Chang, Yu-Kai; Yi, Long-Yan; Li, Jing-Cheng; Zuo, Xi-Nian


    Tai Chi Chuan (TCC) practice is currently intentionally applied in clinical populations, especially those with cardiovascular diseases because of its potential benefits on the autonomic nervous system. The long-term effect of TCC practice on heart rate variability (HRV) remains largely unknown. In this study, we recruited 23 TCC practitioners whose experience averaged approximately 21 years and 19 controls matched by age, sex and education to examine the effect of TCC practice on the autonomic nervous system during a resting state and during an abdominal breathing state. HRV was measured by traditional electrocardiogram (ECG) recording. The results showed that the low frequency, total power frequency, and normalized low frequency components and the low-frequency/high-frequency ratio were significantly higher, whereas the normalized high frequency was significantly lower in the TCC practitioners relative to controls during the abdominal breathing state. However, we did not detect any significant difference in the HRV measures during the resting state between the two groups. Additionally, TCC experience did not correlate with HRV components either in the abdominal state or the resting state in the TCC group. Considering all of these findings, we suggest that TCC improves vagal activity and the balance between sympathetic and parasympathetic activity during the relaxation state. This study also provides direct physiological evidence for the role of TCC practice in relaxation.

  2. Protective supplied breathing air garment (United States)

    Childers, Edward L.; von Hortenau, Erik F.


    A breathing air garment for isolating a wearer from hostile environments containing toxins or irritants includes a suit and a separate head protective enclosure or hood engaging a suit collar in sealing attachment. The hood and suit collar are cylindrically shaped and dimensioned to enable the wearer to withdraw his hands from the suit sleeves to perform manual tasks within the hood interior. Breathing air is supplied from an external air line with an air delivery hose attached to the hood interior. The hose feeds air into an annular halo-like fiber-filled plenum having spaced discharge orifices attached to the hood top wall. A plurality of air exhaust/check valves located at the suit extremities cooperate with the hood air delivery system to provide a cooling flow of circulating air from the hood throughout the suit interior. A suit entry seal provided on the suit rear torso panel permits access into the suit and is sealed with an adhesive sealing flap.

  3. Where is the rhythm generator for emotional breathing? (United States)

    Masaoka, Yuri; Izumizaki, Masahiko; Homma, Ikuo


    As a result of recent progress in brain imaging techniques, a number of studies have been able to identify anatomical correlates of various emotions (Pujol et al., 2013; Tettamanti et al., 2012; van der Zwaag et al., 2012). However, emotions are not solely a phenomenon within the brain-they are also composed of body responses. These include autonomic and behavioral responses, such as changes in heart rate, blood pressure, skin conductance, and respiration. Among these physiological responses, respiration has a unique relationship to emotion. While the primary role of respiration concerns metabolism and homeostasis, emotions such as disgust, anger, and happiness also influence respiratory activities (Boiten et al., 1994). While respiratory change that accompanies emotions can occur unconsciously, respiration can also be voluntarily altered associating with an activation of the motor cortex. There may be no physiological expression for the association between the three areas of the brain that regulate respiration: the brainstem, the limbic system, and the cerebral cortex. The brainstem works to maintain homeostasis, the limbic system is responsible for emotional processing, and the cerebral cortex controls intention. Investigating the interaction between these brain regions may lead to an explanation about why they are so widely dispersed in the brain, despite their common role in the regulation of respiration. In this chapter, we review our findings on breathing behavior and discuss the mechanisms underlying the relationship between emotion and respiration.

  4. Relationship between Musical Characteristics and Temporal Breathing Pattern in Piano Performance (United States)

    Sakaguchi, Yutaka; Aiba, Eriko


    Although there is growing evidence that breathing is modulated by various motor and cognitive activities, the nature of breathing in musical performance has been little explored. The present study examined the temporal breath pattern in piano performance, aiming to elucidate how breath timing is related to musical organization/events and performance. In the experiments, the respiration of 15 professional and amateur pianists, playing 10 music excerpts in total (from four-octave C major scale, Hanon's exercise, J. S. Bach's Invention, Mozart's Sonatas, and Debussy's Clair de lune), was monitored by capnography. The relationship between breathing and musical characteristics was analyzed. Five major results were obtained. (1) Mean breath interval was shortened for excerpts in faster tempi. (2) Fluctuation of breath intervals was reduced for the pieces for finger exercise and those in faster tempi. Pianists showing large within-trial fluctuation also exhibited large inter-excerpt difference. (3) Inter-trial consistency of the breath patterns depended on the excerpts. Consistency was generally reduced for the excerpts that could be performed mechanically (i.e., pieces for finger exercise), but interestingly, one third of the participant showed consistent patterns for the simple scale, correlated with the ascending/descending sequences. (4) Pianists tended to exhale just after the music onsets, inhale at the rests, and inhibit inhale during the slur parts. There was correlation between breathing pattern and two-voice polyphonic structure for several participants. (5) Respiratory patterns were notably different among the pianists. Every pianist showed his or her own characteristic features commonly for various musical works. These findings suggest that breathing in piano performance depends not only on musical parameters and organization written in the score but also some pianist-dependent factors which might be ingrained to individual pianists. PMID:27516736

  5. Relationship between Musical Characteristics and Temporal Breathing Pattern in Piano Performance. (United States)

    Sakaguchi, Yutaka; Aiba, Eriko


    Although there is growing evidence that breathing is modulated by various motor and cognitive activities, the nature of breathing in musical performance has been little explored. The present study examined the temporal breath pattern in piano performance, aiming to elucidate how breath timing is related to musical organization/events and performance. In the experiments, the respiration of 15 professional and amateur pianists, playing 10 music excerpts in total (from four-octave C major scale, Hanon's exercise, J. S. Bach's Invention, Mozart's Sonatas, and Debussy's Clair de lune), was monitored by capnography. The relationship between breathing and musical characteristics was analyzed. Five major results were obtained. (1) Mean breath interval was shortened for excerpts in faster tempi. (2) Fluctuation of breath intervals was reduced for the pieces for finger exercise and those in faster tempi. Pianists showing large within-trial fluctuation also exhibited large inter-excerpt difference. (3) Inter-trial consistency of the breath patterns depended on the excerpts. Consistency was generally reduced for the excerpts that could be performed mechanically (i.e., pieces for finger exercise), but interestingly, one third of the participant showed consistent patterns for the simple scale, correlated with the ascending/descending sequences. (4) Pianists tended to exhale just after the music onsets, inhale at the rests, and inhibit inhale during the slur parts. There was correlation between breathing pattern and two-voice polyphonic structure for several participants. (5) Respiratory patterns were notably different among the pianists. Every pianist showed his or her own characteristic features commonly for various musical works. These findings suggest that breathing in piano performance depends not only on musical parameters and organization written in the score but also some pianist-dependent factors which might be ingrained to individual pianists.

  6. Automotive active noise control (ANC) system. Jidoshayo active noise control (ANC) system

    Energy Technology Data Exchange (ETDEWEB)

    Hasegawa, S. (Nissan Motor Co. Ltd., Tokyo (Japan))


    This paper introduces a successful development of an active noise control (ANC) system that selects and controls noise in an automobile compartment. This is a system that Nissan has developed for practical use for the first time in the world by using an adaptive control theory and a digital signal processor (DSP) that uses ultra-high speed operating elements. The principle for noise silencing in the ANC system utilizes interference of cyclic amplitude of sound with opposite phase. Sounds in an automobile include informative sounds, agreeable sounds, and noise, and combinations of these sounds work complexly on people in a car, of which extent varies depending on individuals. The adaptive control minimizes sounds picked up by a microphone into controlled speaker sound via an multiple error filtered algorithm (MEF-[sub X]LMS) and an adaptive digital filter. Major components of the system include a microphone, a speaker, and a control unit (comprising the adaptive algorithm and the adaptive filter), all having been developed newly. A DSP that operates on ultra-high speed operating elements was used for speedy compliance with complex algorithms, so that the controlled sound combined of engine noise with compartment sound field can be calculated. The noise was reduced by more than 10 dB at maximum. 7 figs.

  7. Piezoresistive Membrane Surface Stress Sensors for Characterization of Breath Samples of Head and Neck Cancer Patients

    Directory of Open Access Journals (Sweden)

    Hans Peter Lang


    Full Text Available For many diseases, where a particular organ is affected, chemical by-products can be found in the patient’s exhaled breath. Breath analysis is often done using gas chromatography and mass spectrometry, but interpretation of results is difficult and time-consuming. We performed characterization of patients’ exhaled breath samples by an electronic nose technique based on an array of nanomechanical membrane sensors. Each membrane is coated with a different thin polymer layer. By pumping the exhaled breath into a measurement chamber, volatile organic compounds present in patients’ breath diffuse into the polymer layers and deform the membranes by changes in surface stress. The bending of the membranes is measured piezoresistively and the signals are converted into voltages. The sensor deflection pattern allows one to characterize the condition of the patient. In a clinical pilot study, we investigated breath samples from head and neck cancer patients and healthy control persons. Evaluation using principal component analysis (PCA allowed a clear distinction between the two groups. As head and neck cancer can be completely removed by surgery, the breath of cured patients was investigated after surgery again and the results were similar to those of the healthy control group, indicating that surgery was successful.

  8. Piezoresistive Membrane Surface Stress Sensors for Characterization of Breath Samples of Head and Neck Cancer Patients. (United States)

    Lang, Hans Peter; Loizeau, Frédéric; Hiou-Feige, Agnès; Rivals, Jean-Paul; Romero, Pedro; Akiyama, Terunobu; Gerber, Christoph; Meyer, Ernst


    For many diseases, where a particular organ is affected, chemical by-products can be found in the patient's exhaled breath. Breath analysis is often done using gas chromatography and mass spectrometry, but interpretation of results is difficult and time-consuming. We performed characterization of patients' exhaled breath samples by an electronic nose technique based on an array of nanomechanical membrane sensors. Each membrane is coated with a different thin polymer layer. By pumping the exhaled breath into a measurement chamber, volatile organic compounds present in patients' breath diffuse into the polymer layers and deform the membranes by changes in surface stress. The bending of the membranes is measured piezoresistively and the signals are converted into voltages. The sensor deflection pattern allows one to characterize the condition of the patient. In a clinical pilot study, we investigated breath samples from head and neck cancer patients and healthy control persons. Evaluation using principal component analysis (PCA) allowed a clear distinction between the two groups. As head and neck cancer can be completely removed by surgery, the breath of cured patients was investigated after surgery again and the results were similar to those of the healthy control group, indicating that surgery was successful.

  9. Submarines, spacecraft and exhaled breath. (United States)

    Pleil, Joachim D; Hansel, Armin


    Foreword The International Association of Breath Research (IABR) meetings are an eclectic gathering of researchers in the medical, environmental and instrumentation fields; our focus is on human health as assessed by the measurement and interpretation of trace chemicals in human exhaled breath. What may have escaped our notice is a complementary field of research that explores the creation and maintenance of artificial atmospheres practised by the submarine air monitoring and air purification (SAMAP) community. SAMAP is comprised of manufacturers, researchers and medical professionals dealing with the engineering and instrumentation to support human life in submarines and spacecraft (including shuttlecraft and manned rockets, high-altitude aircraft, and the International Space Station (ISS)). Here, the immediate concerns are short-term survival and long-term health in fairly confined environments where one cannot simply 'open the window' for fresh air. As such, one of the main concerns is air monitoring and the main sources of contamination are CO(2) and other constituents of human exhaled breath. Since the inaugural meeting in 1994 in Adelaide, Australia, SAMAP meetings have been held every two or three years alternating between the North American and European continents. The meetings are organized by Dr Wally Mazurek (a member of IABR) of the Defense Systems Technology Organization (DSTO) of Australia, and individual meetings are co-hosted by the navies of the countries in which they are held. An overriding focus at SAMAP is life support (oxygen availability and carbon dioxide removal). Certainly, other air constituents are also important; for example, the closed environment of a submarine or the ISS can build up contaminants from consumer products, cooking, refrigeration, accidental fires, propulsion and atmosphere maintenance. However, the most immediate concern is sustaining human metabolism: removing exhaled CO(2) and replacing metabolized O(2). Another

  10. 42 CFR 84.141 - Breathing gas; minimum requirements. (United States)


    ... Respirators § 84.141 Breathing gas; minimum requirements. (a) Breathing gas used to supply supplied-air respirators shall be respirable breathing air and contain no less than 19.5 volume-percent of oxygen....

  11. How Does a Hopping Kangaroo Breathe? (United States)

    Giuliodori, Mauricio J.; Lujan, Heidi L.; Janbaih, Hussein; DiCarlo, Stephen E.


    We developed a model to demonstrate how a hopping kangaroo breathes. Interestingly, a kangaroo uses less energy to breathe while hopping than while standing still. This occurs, in part, because rather than using muscle power to move air into and out of the lungs, air is pulled into (inspiration) and pushed out of (expiration) the lungs as the…

  12. Oral breathing: new early treatment protocol

    Directory of Open Access Journals (Sweden)

    Gloria Denotti


    Full Text Available Oral breathing is a respiratory dysfunction that affects approximately 10-15% of child population. It is responsable of local effects and systemic effects, both immediate and long-term. They affect the growth of the subject and his physical health in many ways: pediatric, psycho-behavioral and cognitive. The etiology is multifactorial. It’s important the establishment of a vicious circle involving more areas and it is essential to stop it as soon as possible. In order to correct this anomaly, the pediatric dentist must be able to make a correct diagnosis to treat early the disfunction and to avoid the onset of cascade mechanisms. Who plays a central role is the pediatrician who first and frequently come into contact with little patients. He can identify the anomalies, and therefore collaborate with other specialists, including the dentist. The key aspect that guides us in the diagnosis, and allows us to identify the oral respirator, is the “adenoid facies”. The purpose of the study is to highlight the importance and benefits of an early and multidisciplinary intervention (pediatric, orthopedic-orthodontic-functional. A sample of 20 patients was selected with the following inclusion criteria: mouth breathing, transverse discrepancy > 4 mm, early mixed dentition, central and lateral permenent incisors, overjet increased, lip and nasal incompetence, snoring and/or sleep apnea episodes. The protocol of intervention includes the use of the following devices and procedures: a maxillary rapid expander (to correct the transverse discrepancy, to increase the amplitude of the upper respiratory airway and to reduce nasal resistances tract in association with myo-functional devices (nasal stimulator and oral obturator. They allow the reconstruction of a physiological balance between the perioral musculature and tongue, the acquisition of nasal and lips competence and the reduction of overjet. This protocol speeds up and stabilizes the results. The

  13. Breathing thermal manikins for indoor environment assessment: important characteristics and requirements

    DEFF Research Database (Denmark)

    Melikov, Arsen Krikor


    Recently breathing thermal manikins have been developed and used for indoor environment measurement, evaluation and optimization as well as validation of Computational Fluid Dynamics (CFD) predictions of airflow around a human body. Advances in the assessment of occupants¿ thermal comfort...... and perceived air quality by means of breathing thermal manikins have been made as well. In order to perform accurate measurements and realistic evaluation and assessment, the design and characteristics of a manikin must comply with certain requirements. The most important of these, such as number, size...... and shape of body segments, control mode, breathing simulation, etc. are discussed and specified in this paper....

  14. Breathing thermal manikin for indoor environment assessment: Important characteristics and requirements

    DEFF Research Database (Denmark)

    Melikov, Arsen Krikor


    Recently breathing thermal manikins have been developed and used for indoor environment measurement, evaluation and optimization as well as validation of Computational Fluid Dynamics (CFD) predictions of airflow around a human body. Advances in the assessment of occupants¿ thermal comfort...... and perceived air quality by means of breathing thermal manikins have been made as well. In order to perform accurate measurements and realistic evaluation and assessment, the design and characteristics of a manikin must comply with certain requirements. The most important of these, such as number, size...... and shape of body segments, control mode, breathing simulation, etc. are discussed and specified in this paper....

  15. EEG paroxysmal gamma waves during Bhramari Pranayama: a yoga breathing technique. (United States)

    Vialatte, François B; Bakardjian, Hovagim; Prasad, Rajkishore; Cichocki, Andrzej


    Here we report that a specific form of yoga can generate controlled high-frequency gamma waves. For the first time, paroxysmal gamma waves (PGW) were observed in eight subjects practicing a yoga technique of breathing control called Bhramari Pranayama (BhPr). To obtain new insights into the nature of the EEG during BhPr, we analyzed EEG signals using time-frequency representations (TFR), independent component analysis (ICA), and EEG tomography (LORETA). We found that the PGW consists of high-frequency biphasic ripples. This unusual activity is discussed in relation to previous reports on yoga and meditation. It is concluded this EEG activity is most probably non-epileptic, and that applying the same methodology to other meditation recordings might yield an improved understanding of the neurocorrelates of meditation.

  16. Physical activity, mindfulness meditation, or heart rate variability biofeedback for stress reduction: a randomized controlled trial. (United States)

    van der Zwan, Judith Esi; de Vente, Wieke; Huizink, Anja C; Bögels, Susan M; de Bruin, Esther I


    In contemporary western societies stress is highly prevalent, therefore the need for stress-reducing methods is great. This randomized controlled trial compared the efficacy of self-help physical activity (PA), mindfulness meditation (MM), and heart rate variability biofeedback (HRV-BF) in reducing stress and its related symptoms. We randomly allocated 126 participants to PA, MM, or HRV-BF upon enrollment, of whom 76 agreed to participate. The interventions consisted of psycho-education and an introduction to the specific intervention techniques and 5 weeks of daily exercises at home. The PA exercises consisted of a vigorous-intensity activity of free choice. The MM exercises consisted of guided mindfulness meditation. The HRV-BF exercises consisted of slow breathing with a heart rate variability biofeedback device. Participants received daily reminders for their exercises and were contacted weekly to monitor their progress. They completed questionnaires prior to, directly after, and 6 weeks after the intervention. Results indicated an overall beneficial effect consisting of reduced stress, anxiety and depressive symptoms, and improved psychological well-being and sleep quality. No significant between-intervention effect was found, suggesting that PA, MM, and HRV-BF are equally effective in reducing stress and its related symptoms. These self-help interventions provide easily accessible help for people with stress complaints.

  17. Pulse pressure variation to predict fluid responsiveness in spontaneously breathing patients: tidal vs. forced inspiratory breathing. (United States)

    Hong, D M; Lee, J M; Seo, J H; Min, J J; Jeon, Y; Bahk, J H


    We evaluated whether pulse pressure variation can predict fluid responsiveness in spontaneously breathing patients. Fifty-nine elective thoracic surgical patients were studied before induction of general anaesthesia. After volume expansion with hydroxyethyl starch 6 , patients were defined as responders by a ≥ 15% increase in the cardiac index. Haemodynamic variables were measured before and after volume expansion and pulse pressure variations were calculated during tidal breathing and during forced inspiratory breathing. Median (IQR [range]) pulse pressure variation during forced inspiratory breathing was significantly higher in responders (n = 29) than in non-responders (n = 30) before volume expansion (18.2 (IQR 14.7-18.2 [9.3-31.3])% vs. 10.1 (IQR 8.3-12.6 [4.8-21.1])%, respectively, p breathing could predict fluid responsiveness (area under the curve 0.910, p breathing can be used to guide fluid management in spontaneously breathing patients.

  18. Discriminating between Nasal and Mouth Breathing

    CERN Document Server

    Curran, Kevin; Coyle, Damian


    The recommendation to change breathing patterns from the mouth to the nose can have a significantly positive impact upon the general well being of the individual. We classify nasal and mouth breathing by using an acoustic sensor and intelligent signal processing techniques. The overall purpose is to investigate the possibility of identifying the differences in patterns between nasal and mouth breathing in order to integrate this information into a decision support system which will form the basis of a patient monitoring and motivational feedback system to recommend the change from mouth to nasal breathing. Our findings show that the breath pattern can be discriminated in certain places of the body both by visual spectrum analysis and with a Back Propagation neural network classifier. The sound file recoded from the sensor placed on the hollow in the neck shows the most promising accuracy which is as high as 90%.

  19. Abortion--the breath of life. (United States)

    Joling, R J


    A scholarly review of medical-legal and biblical authority on the su bject of abortion supports abortion as a woman's right when it is performed before the fetus has had its "breath of life." Based on biblical evidence, a person becomes a living being when the soul, the "breath of life" is breathed into it. Without the "breath of life" no person exists. A fetus less than 28 weeks old is incapable of breathing alone; thus an aborted fetus that age is not truly a living human being capable of surviving independently of its mother's womb. Legal aspects include supreme, local and state court decisions defining abortion. It is ultimately expected that each person will determine what approach to take towards the abortion question. Abortion is still a personal problem regardless of supreme court decisions or ecclesiastical determinants. Religion and moral concepts should be the guiding conscience involved in the question of abortion.

  20. State-reconstruction-based robust backstepping control of air-breathing hypersonic vehicles%基于状态重构的吸气式高超声速飞行器鲁棒反演控制

    Institute of Scientific and Technical Information of China (English)

    卜祥伟; 吴晓燕; 马震; 张蕊


    A robust backstepping controller was designed based on state reconstruction for flexible air⁃breathing hypersonic ve⁃hicles considering that only the velocity,altitude and pitch rate were observable. Firstly,the controlled plant was rewritten as a strict feedback form,and the actual control laws and virtual control laws were designed based on dynamic inversion and backstepping re⁃spectively. Secondly,arctangent tracking differentiator was introduced to estimate the derivatives of virtual control laws and recon⁃struct the states of flight⁃path angle and angle of attack.Finally,in order to guarantee the backstepping controller'robustness,a new nonlinear disturbance observer was designed based on nonlinear⁃linear tracking differentiator to estimate and compensate uncertain⁃ties of the model precisely.Simulation results show that a high precise state construction can be obtained by the proposed strategy and the presented control methodology can provide a stable altitude and velocity tracking,and eliminate the influence of the uncer⁃tainties of the model.%针对吸气式高超声速飞行器参数不确定弹性体模型,仅考虑速度、高度和俯仰角速度可测的情况,提出了一种基于状态重构的鲁棒反演控制器设计方法。首先,将被控对象模型表示为严格反馈形式,分别采用动态逆和反演设计实际控制律和虚拟控制律;其次,引入反正切跟踪微分器来简化虚拟控制律求导运算,并用于对弹道角和攻角进行状态重构;最后,为了保证反演控制器的鲁棒性,基于非线性⁃线性跟踪微分器,设计了一种新型非线性干扰观测器,可实现对模型不确定项的精确估计和补偿。仿真结果表明,所提策略取得了较高的状态重构精度,控制器能够克服模型不确定项的影响,且能保证速度和高度对参考输入的稳定跟踪。

  1. Optimal Control of Active Recoil Mechanisms (United States)


    pressures in different chambers, rod pull are available and can be plotted. A linear state feedback control system is proposed to adapt this...desirable. A linear state feedback control system with variable gains is proposed in the report. A separate control law is designed for each...optimization algorithm to choose a feasible solution. 27 3.3 Results for M-37 Recoil Mechanism The linear state feedback control system and

  2. Low Activity Waste Feed Process Control Strategy

    Energy Technology Data Exchange (ETDEWEB)

    STAEHR, T.W.


    The primary purpose of this document is to describe the overall process control strategy for monitoring and controlling the functions associated with the Phase 1B high-level waste feed delivery. This document provides the basis for process monitoring and control functions and requirements needed throughput the double-shell tank system during Phase 1 high-level waste feed delivery. This document is intended to be used by (1) the developers of the future Process Control Plan and (2) the developers of the monitoring and control system.

  3. Resonant breathing biofeedback training for stress reduction among manufacturing operators. (United States)

    Sutarto, Auditya Purwandini; Wahab, Muhammad Nubli Abdul; Zin, Nora Mat


    The aim of this study was to examine the effect of resonant breathing biofeedback training for reducing stress among manufacturing operators. Resonant breathing biofeedback works by teaching people to recognize their involuntary heart rate variability and to control patterns of this physiological response. Thirty-six female operators from an electronic manufacturing factory were randomly assigned as the experimental group (n = 19) and the control group (n = 17). The participants of the intervention received 5 weekly sessions of biofeedback training. Physiological stress profiles and self-perceived depression, anxiety, and stress scale (DASS) were assessed at pre- and post-intervention. Results indicated that depression, anxiety, and stress significantly decreased after the training in the experimental group; they were supported by a significant increase in physiological measures. Overall, these results support the potential application of resonant biofeedback training to reduce negative emotional symptoms among industrial workers.

  4. Time Breath of Psychological Theories

    DEFF Research Database (Denmark)

    Tateo, Luca; Valsiner, Jaan


    Psychology as a self-aspiring, ambitious, developmental science faces the crucial limit of time—both theoretically and practically. The issue of time in constructing psychology’s theories is a major unresolved metatheoretical task. This raises several questions about generalization of knowledge......: which is the time length of breath of psychological theories? Which is the temporal dimension of psychological processes? In this article we discuss the role of different axiomatic assumptions about time in the construction of psychological theories. How could different theories include a concept...... of time—or fail to do that? How can they generalize with respect to time? The different conceptions of time often remain implicit, while shaping the concepts used in understanding psychological processes. Any preconception about time in human development will foster the generalizability of theory, as well...

  5. 77 FR 37862 - Open-Circuit Self-Contained Breathing Apparatus Remaining Service-Life Indicator Performance... (United States)


    ... respirator's reserve breathing air supply. While modern practice is for firefighters to practice ``air... Service-Life Indicator Performance Requirements AGENCY: Centers for Disease Control and Prevention, HHS... revision to the current requirement for open-circuit self-contained breathing apparatus (OC-...

  6. DSP Control of Line Hybrid Active Filter

    DEFF Research Database (Denmark)

    Dan, Stan George; Benjamin, Doniga Daniel; Magureanu, R.;


    Active Power Filters have been intensively explored in the past decade. Hybrid active filters inherit the efficiency of passive filters and the improved performance of active filters, and thus constitute a viable improved approach for harmonic compensation. In this paper a parallel hybrid filter ...

  7. Development of an Exhaled Breath Monitoring System with Semiconductive Gas Sensors, a Gas Condenser Unit, and Gas Chromatograph Columns

    Directory of Open Access Journals (Sweden)

    Toshio Itoh


    Full Text Available Various volatile organic compounds (VOCs in breath exhaled by patients with lung cancer, healthy controls, and patients with lung cancer who underwent surgery for resection of cancer were analyzed by gas condenser-equipped gas chromatography-mass spectrometry (GC/MS for development of an exhaled breath monitoring prototype system involving metal oxide gas sensors, a gas condenser, and gas chromatography columns. The gas condenser-GC/MS analysis identified concentrations of 56 VOCs in the breath exhaled by the test population of 136 volunteers (107 patients with lung cancer and 29 controls, and selected four target VOCs, nonanal, acetoin, acetic acid, and propanoic acid, for use with the condenser, GC, and sensor-type prototype system. The prototype system analyzed exhaled breath samples from 101 volunteers (74 patients with lung cancer and 27 controls. The prototype system exhibited a level of performance similar to that of the gas condenser-GC/MS system for breath analysis.

  8. Development of an Exhaled Breath Monitoring System with Semiconductive Gas Sensors, a Gas Condenser Unit, and Gas Chromatograph Columns. (United States)

    Itoh, Toshio; Miwa, Toshio; Tsuruta, Akihiro; Akamatsu, Takafumi; Izu, Noriya; Shin, Woosuck; Park, Jangchul; Hida, Toyoaki; Eda, Takeshi; Setoguchi, Yasuhiro


    Various volatile organic compounds (VOCs) in breath exhaled by patients with lung cancer, healthy controls, and patients with lung cancer who underwent surgery for resection of cancer were analyzed by gas condenser-equipped gas chromatography-mass spectrometry (GC/MS) for development of an exhaled breath monitoring prototype system involving metal oxide gas sensors, a gas condenser, and gas chromatography columns. The gas condenser-GC/MS analysis identified concentrations of 56 VOCs in the breath exhaled by the test population of 136 volunteers (107 patients with lung cancer and 29 controls), and selected four target VOCs, nonanal, acetoin, acetic acid, and propanoic acid, for use with the condenser, GC, and sensor-type prototype system. The prototype system analyzed exhaled breath samples from 101 volunteers (74 patients with lung cancer and 27 controls). The prototype system exhibited a level of performance similar to that of the gas condenser-GC/MS system for breath analysis.

  9. Avaliação da responsividade a volume em pacientes sob ventilação espontânea Assessment of fluid responsiveness in patients under spontaneous breathing activity

    Directory of Open Access Journals (Sweden)

    Fernando José da Silva Ramos


    Full Text Available A avaliação da responsividade a volume no paciente em ventilação espontânea representa um desafio para o intensivista. A maior parte dos conhecimentos adquiridos sobre interação coração-pulmão e o cálculo de índices dinâmicos de responsividade a fluidos podem não ser adequados para essa avaliação. Historicamente, as variáveis mais frequentemente utilizadas para guiar a responsividade a volume têm sido as medidas estáticas de pré-carga. Mais recentemente, índices dinâmicos obtidos por dispositivos menos invasivos têm sido mais usados, apesar de sua eficácia para esse fim em pacientes em ventilação espontânea ainda não ter sido adequadamente estabelecida. O objetivo deste estudo foi revisar as principais evidências sobre a avaliação da responsividade a volume nos pacientes em ventilação espontânea. A pesquisa na literatura demonstrou escassez nas evidências para utilização de medidas estáticas da volemia como as pressões de enchimento e o volume diastólico final dos ventrículos. Medidas dinâmicas como variação da pressão de pulso e outros índices também não foram adequadamente testados durante a ventilação espontânea. Resultados favoráveis foram obtidos com a variação dinâmica da pressão venosa central e com parâmetros dinâmicos que utilizam o ecocardiograma transtorácico ou doppler esofágico associado à elevação passiva dos membros inferiores. Conclui-se que embora a variação da pressão venosa central e variáveis obtidas com o ecocardiograma transtorácico ou doppler esofágico possam ser úteis na avaliação da responsividade a volume em pacientes sob ventilação espontânea, definitivamente são necessários mais estudos neste grupo de pacientes.To assess fluid responsiveness in patients under spontaneous breathing activity ventilation remains a challenge for intensive care physicians. Much of the knowledge on heart-lung interactions and dynamic indexes of fluid responsiveness

  10. Breath formate is a marker of airway S-nitrosothiol depletion in severe asthma.

    Directory of Open Access Journals (Sweden)

    Roby Greenwald

    Full Text Available BACKGROUND: Children with severe asthma have poor symptom control and elevated markers of airway oxidative and nitrosative stress. Paradoxically, they have decreased airway levels of S-nitrosothiols (SNOs, a class of endogenous airway smooth muscle relaxants. This deficiency results from increased activity of an enzyme that both reduces SNOs to ammonia and oxidizes formaldehyde to formic acid, a volatile carboxylic acid that is more easily detected in exhaled breath condensate (EBC than SNOs. We therefore hypothesize that depletion of airway SNOs is related to asthma pathology, and breath formate concentration may be a proxy measure of SNO catabolism. METHODS AND FINDINGS: We collected EBC samples from children and adolescents, including 38 with severe asthma, 46 with mild-to-moderate asthma and 16 healthy adolescent controls, and the concentration of ionic constituents was quantified using ion chromatography. The concentrations of EBC components with volatile conjugates were log-normally distributed. Formate was the principal ion that displayed a significant difference between asthma status classifications. The mean EBC formate concentration was 40% higher in samples collected from all asthmatics than from healthy controls (mean = 5.7 microM, mean+/-standard deviation = 3.1-10.3 microM vs. 4.0, 2.8-5.8 microM, p = 0.05. EBC formate was higher in severe asthmatics than in mild-to-moderate asthmatics (6.8, 3.7-12.3 microM vs. 4.9, 2.8-8.7 microM, p = 0.012. In addition, formate concentration was negatively correlated with methacholine PC(20 (r = -0.39, p = 0.002, asthmatics only, and positively correlated with the NO-derived ion nitrite (r = 0.46, p<0.0001 as well as with total serum IgE (r = 0.28, p = 0.016, asthmatics only. Furthermore, formate was not significantly correlated with other volatile organic acids nor with inhaled corticosteroid dose. CONCLUSIONS: We conclude that EBC formate concentration is significantly higher in the breath of

  11. Combustion instability and active control: Alternative fuels, augmentors, and modeling heat release (United States)

    Park, Sammy Ace

    Experimental and analytical studies were conducted to explore thermo-acoustic coupling during the onset of combustion instability in various air-breathing combustor configurations. These include a laboratory-scale 200-kW dump combustor and a 100-kW augmentor featuring a v-gutter flame holder. They were used to simulate main combustion chambers and afterburners in aero engines, respectively. The three primary themes of this work includes: 1) modeling heat release fluctuations for stability analysis, 2) conducting active combustion control with alternative fuels, and 3) demonstrating practical active control for augmentor instability suppression. The phenomenon of combustion instabilities remains an unsolved problem in propulsion engines, mainly because of the difficulty in predicting the fluctuating component of heat release without extensive testing. A hybrid model was developed to describe both the temporal and spatial variations in dynamic heat release, using a separation of variables approach that requires only a limited amount of experimental data. The use of sinusoidal basis functions further reduced the amount of data required. When the mean heat release behavior is known, the only experimental data needed for detailed stability analysis is one instantaneous picture of heat release at the peak pressure phase. This model was successfully tested in the dump combustor experiments, reproducing the correct sign of the overall Rayleigh index as well as the remarkably accurate spatial distribution pattern of fluctuating heat release. Active combustion control was explored for fuel-flexible combustor operation using twelve different jet fuels including bio-synthetic and Fischer-Tropsch types. Analysis done using an actuated spray combustion model revealed that the combustion response times of these fuels were similar. Combined with experimental spray characterizations, this suggested that controller performance should remain effective with various alternative fuels

  12. A MATLAB toolbox for correcting within-individual effects of respiration rate and tidal volume on respiratory sinus arrhythmia during variable breathing. (United States)

    Schulz, Stefan M; Ayala, Erica; Dahme, Bernhard; Ritz, Thomas


    Respiratory sinus arrhythmia (RSA) is a common estimator of vagal outflow to the heart, dependent on parasympathetic activity. During variable breathing, both respiration rate and tidal volume contribute substantially to within-individual RSA variance. A respiratory control method allows for within-individual correction of the time-domain index of RSA. rsaToolbox is a set of MATLAB programs for scoring respiration-corrected RSA using measurements of cardiac interbeat intervals, respiratory-cycle times, and tidal volumes, recorded at different paced-breathing frequencies. The within-individual regression of RSA divided by tidal volume upon total respiratory cycle time is then used to estimate the baseline vagal tone for each breath of a given total respiratory-cycle time. During a subsequent analysis, the difference between the observed RSA (divided by the tidal volume at each breath) and the RSA divided by the tidal volume that was predicted by the baseline equation serves as an estimate of changes in vagal tone. rsaToolbox includes a graphical user interface for intuitive handling. Modular implementation of the algorithm also allows for flexible integration within other analytic strategies or for batch processing.

  13. Fractionated irradiation combined with carbogen breathing and nicotinamide of two human glioblastomas grafted in nude mice


    Sun, Lin-Quan; Buchegger, Franz; Coucke, Philippe; MIRIMANOFF


    This study addressed the potential radiosensitizing effect of nicotinamide and/or carbogen on human glioblastoma xenografts in nude mice. U-87MG and LN-Z308 tumors were irradiated with either 20 fractions over 12 days or 5 fractions over 5 days in air-breathing mice, mice injected with nicotinamide, mice breathing carbogen, or mice receiving nicotinamide plus carbogen. The responses to treatment were assessed using local control and moist desquamation. In U-87MG tumors, the enhancement ratios...

  14. Design and evaluation of an exhaled breath sampler for biological monitoring of organic solvents. (United States)

    Periago, J F; Luna, A; Morente, A; Zambudio, A


    We designed a breath sampler based on a tube which collects the final portion of exhaled air. The passage of successive fractions through a layer of activated charcoal is controlled by a three-way valve. This system was validated in a controlled atmosphere of n-hexane and toluene at four concentrations between 12 and 110 mg m-3 and 12 and 115 mg m-3, respectively. Uptake volumes of 0.1, 0.2 and 0.31 were tested at relative humidities of 46% and 98%. There were no significant differences in the recoveries obtained under any of the conditions tested. We confirmed the reproducibility between successive samples in volunteers and exposed workers, and found no significant differences between the different sampling conditions studied. Our system enriches the sample in an adsorbent cartridge by collecting successive fractions of end-exhaled breath from one or more exhalations until the amount required by the analytical method has been accumulated. It is portable, economical and highly operative in the field.

  15. Diaphragmatic Breathing Reduces Exercise-Induced Oxidative Stress


    Daniele Martarelli; Mario Cocchioni; Stefania Scuri; Pierluigi Pompei


    Diaphragmatic breathing is relaxing and therapeutic, reduces stress, and is a fundamental procedure of Pranayama Yoga, Zen, transcendental meditation and other meditation practices. Analysis of oxidative stress levels in people who meditate indicated that meditation correlates with lower oxidative stress levels, lower cortisol levels and higher melatonin levels. It is known that cortisol inhibits enzymes responsible for the antioxidant activity of cells and that melatonin is a strong antioxid...

  16. Wind Turbine Rotors with Active Vibration Control

    DEFF Research Database (Denmark)

    Svendsen, Martin Nymann

    mode and the combined whirling modes respectively, via a shared set of collocated sensor/actuator pairs. The collective mode controller is decoupled from the whirling mode controller by an exact linear filter, which is identified from the fundamental dynamics of the gyroscopic system. As in the method...

  17. Breathing and sleep at high altitude. (United States)

    Ainslie, Philip N; Lucas, Samuel J E; Burgess, Keith R


    We provide an updated review on the current understanding of breathing and sleep at high altitude in humans. We conclude that: (1) progressive changes in pH initiated by the respiratory alkalosis do not underlie early (48 h), complex cellular and neurochemical re-organization occurs both in the peripheral chemoreceptors as well as within the central nervous system. The latter is likely influenced by central acid-base changes secondary to the extent of the initial respiratory responses to initial exposure to high altitude; (3) sleep at high altitude is disturbed by various factors, but principally by periodic breathing; (4) the extent of periodic breathing during sleep at altitude intensifies with duration and severity of exposure; (5) complex interactions between hypoxic-induced enhancement in peripheral and central chemoreflexes and cerebral blood flow--leading to higher loop gain and breathing instability--underpin this development of periodic breathing during sleep; (6) because periodic breathing may elevate rather than reduce mean SaO2 during sleep, this may represent an adaptive rather than maladaptive response; (7) although oral acetazolamide is an effective means to reduce periodic breathing by 50-80%, recent studies using positive airway pressure devices to increase dead space, hyponotics and theophylline are emerging but appear less practical and effective compared to acetazolamide. Finally, we suggest avenues for future research, and discuss implications for understanding sleep pathology.

  18. Tuning of active vibration controllers for ACTEX by genetic algorithm (United States)

    Kwak, Moon K.; Denoyer, Keith K.


    This paper is concerned with the optimal tuning of digitally programmable analog controllers on the ACTEX-1 smart structures flight experiment. The programmable controllers for each channel include a third order Strain Rate Feedback (SRF) controller, a fifth order SRF controller, a second order Positive Position Feedback (PPF) controller, and a fourth order PPF controller. Optimal manual tuning of several control parameters can be a difficult task even though the closed-loop control characteristics of each controller are well known. Hence, the automatic tuning of individual control parameters using Genetic Algorithms is proposed in this paper. The optimal control parameters of each control law are obtained by imposing a constraint on the closed-loop frequency response functions using the ACTEX mathematical model. The tuned control parameters are then uploaded to the ACTEX electronic control electronics and experiments on the active vibration control are carried out in space. The experimental results on ACTEX will be presented.

  19. Mouth breathing increases the pentylenetetrazole-induced seizure threshold in mice: a role for ATP-sensitive potassium channels. (United States)

    Niaki, Seyed Esfandiar Akhavan; Shafaroodi, Hamed; Ghasemi, Mehdi; Shakiba, Bijan; Fakhimi, Ali; Dehpour, Ahamd Reza


    Nasal obstruction and consequent mouth breathing have been shown to change the acid-base balance, producing respiratory acidosis. Additionally, there exists a large body of evidence maintaining that acidosis affects the activity of ATP-sensitive potassium (K(ATP)) channels, which play a crucial role in the function of the central nervous system (CNS), for example, in modulating seizure threshold. Thus, in the study described here, we examined whether mouth breathing, induced by surgical ligation of nostrils, could affect the seizure threshold induced by pentylenetetrazole in male NMRI mice. Using the selective K(ATP) channel opener (diazoxide) and blocker (glibenclamide), we also evaluated the possible role of K(ATP) channels in this process. Our data revealed that seizure threshold was increased 6 to 72 hours after nasal obstruction, reaching a peak 48 hours afterward, compared with either control or sham-operated mice (Pmouth breathing, which could result in respiratory acidosis, increases seizure threshold in mice and K(ATP) channels may play a role in this effect.

  20. Nitrate control strategies in an activated sludge wastewater treatment process

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Wenhao; Tao, Erpan; Chen, Xiaoquan; Liu, Dawei [South China University of Technology, Guangzhou (China); Liu, Hongbin [Kyung Hee University, Yongin (Korea, Republic of)


    We studied nitrate control strategies in an activated sludge wastewater treatment process (WWTP) based on the activated sludge model. Two control strategies, back propagation for proportional-integral-derivative (BP-PID) and adaptive-network based fuzzy inference systems (ANFIS), are applied in the WWTP. The simulation results show that the simple local constant setpoint control has poor control effects on the nitrate concentration control. However, the ANFIS (4*1) controller, which considers not only the local constant setpoint control of the nitrate concentration, but also three important indices in the effluent--ammonia concentration, total suspended sludge concentration and total nitrogen concentration--demonstrates good control performance. The results also prove that ANFIS (4*1) controller has better control performance than that of the controllers PI, BP-PID and ANFIS (2*1), and that the ANFIS (4*1) controller is effective in improving the effluent quality and maintaining the stability of the effluent quality.

  1. Extrathoracic and intrathoracic removal of O3 in tidal-breathing humans

    Energy Technology Data Exchange (ETDEWEB)

    Gerrity, T.R.; Weaver, R.A.; Berntsen, J.; House, D.E.; O' Neil, J.J.


    We measured the efficiency of O3 removal from inspired air by the extrathoracic and intrathoracic airways in 18 healthy, nonsmoking, young male volunteers. Removal efficiencies were measured as a function of O3 concentration (0.1, 0.2, and 0.4 ppm), mode of breathing (nose only, mouth only, and oronasal), and respiration frequency (12 and 24 breaths/min). Subjects were placed in a controlled environmental chamber into which O3 was introduced. A small polyethylene tube was then inserted into the nose of each subject, with the tip positioned in the posterior pharynx. Samples of air were collected from the posterior pharynx through the tube and into a rapidly responding O3 analyzer yielding inspiratory and expiratory O3 concentrations in the posterior pharynx. The O3 removal efficiency of the extrathoracic airways was computed with the use of the inspiratory concentration and the chamber concentration, and intrathoracic removal efficiency was computed with the use of the inspiratory and expiratory concentrations. The mean extrathoracic removal efficiency for all measurements was 39.6 +/- 0.7% (SE), and the mean intrathoracic removal efficiency was 91.0 +/- 0.5%. Significantly less O3 was removed both extrathoracically and intrathoracically when subjects breathed at 24 breaths/min compared with 12 breaths/min (P less than 0.001). O3 concentration had no effect on extrathoracic removal efficiency, but there was a significantly greater intrathoracic removal efficiency at 0.4 ppm than at 0.1 ppm (P less than 0.05). Mode of breathing significantly affected extrathoracic removal efficiency, with less O3 removed during nasal breathing than during either mouth breathing or oronasal breathing (P less than 0.01).

  2. Active vibration and noise control by hybrid active acoustic panels

    Energy Technology Data Exchange (ETDEWEB)

    Stoebener, U.; Gaul, L. [Stuttgart Univ. (Germany). Inst. A fuer Mechanik


    In the present paper a hybrid passive and active treatment for vibration and noise reduction of plate type structures is proposed. The treatment is manufactured as sandwich structure and is called hybrid active acoustic panel. The passive component is used to reduce the vibration and sound radiation for high frequencies whereas the active part of the system is designed for the low frequency range. By selecting the thickness of the passive damping layer a certain frequency limit is defined, which divides the high and low frequency range. The actuator and sensor layout of the active component is evaluated by using the mode shapes of the low frequency range. According to the evaluated layout a hybrid active acoustic panel is manufactured and experimentally tested. The experimental results validate the proposed concept. (orig.)

  3. Real time transit dosimetry for the breath-hold radiotherapy technique: An initial experience

    Energy Technology Data Exchange (ETDEWEB)

    Piermattei, Angelo; Cilla, Savino; Grimaldi, Luca (Istituto di Fisica, Universitagrave Cattolica S. Cuore, Roma (Italy)) (and others)


    Introduction. The breath-hold is one of the techniques to obtain the dose escalation for lung tumors. However, the change of the patient's breath pattern can influence the stability of the inhaled air volume, IAV, used in this work as a surrogate parameter to assure the tumor position reproducibility during dose delivery. Materials. and method. In this paper, an Elekta active breathing coordinator has been used for lung tumor irradiation. This device is not an absolute spirometer and the feasibility study here presented developed (i) the possibility to select a specific range epsilon of IAV values comfortable for the patient and (ii) the ability of a transit signal rate, obtained by a small ion-chamber positioned on the portal image device, to supply in real time the in vivo isocenter dose reproducibility. Indeed, while the selection of the IAV range depends on the patient's ability to follow instructions for breath-hold, the monitoring can supply to the radiation therapist a surrogate of the tumor irradiation reproducibility. Results. The detection of the (image) in real time during breath-hold was used to determine the interfraction isocenter dose variations due to the reproducibility of the patient's breathing pattern. The agreement between the reconstructed and planned isocenter dose in breath-hold at the interfraction level was well within 1.5%, while in free breathing a disagreement up to 8% was observed. The standard deviation of the [image omitted] in breath-hold observed at the intrafraction level is a bit higher than the one obtained without the patient and this can be justified by the presence of a small residual tumor motion as heartbeat. Conclusion. The technique is simple and can be implemented for routine use in a busy clinic

  4. Breath acetone monitoring by portable Si:WO{sub 3} gas sensors

    Energy Technology Data Exchange (ETDEWEB)

    Righettoni, Marco; Tricoli, Antonio; Gass, Samuel [Particle Technology Laboratory, Department of Mechanical and Process Engineering ETH Zurich, CH-8092 Zurich (Switzerland); Schmid, Alex; Amann, Anton [Univ.-Clinic for Anesthesia, Innsbruck Medical University, A-6020 Innsbruck (Austria); Breath Research Institute of the Austrian Academy of Sciences, A-6850 Dornbirn (Austria); Pratsinis, Sotiris E., E-mail: [Particle Technology Laboratory, Department of Mechanical and Process Engineering ETH Zurich, CH-8092 Zurich (Switzerland)


    Highlights: Black-Right-Pointing-Pointer Portable sensors were developed and tested for monitoring acetone in the human breath. Black-Right-Pointing-Pointer Acetone concentrations down to 20 ppb were measured with short response times (<30 s). Black-Right-Pointing-Pointer The present sensors were highly selective to acetone over ethanol and water. Black-Right-Pointing-Pointer Sensors were applied to human breath: good agreement with highly sensitive PTR-MS. Black-Right-Pointing-Pointer Tests with people at rest and during physical activity showed the sensor robustness. - Abstract: Breath analysis has the potential for early stage detection and monitoring of illnesses to drastically reduce the corresponding medical diagnostic costs and improve the quality of life of patients suffering from chronic illnesses. In particular, the detection of acetone in the human breath is promising for non-invasive diagnosis and painless monitoring of diabetes (no finger pricking). Here, a portable acetone sensor consisting of flame-deposited and in situ annealed, Si-doped epsilon-WO{sub 3} nanostructured films was developed. The chamber volume was miniaturized while reaction-limited and transport-limited gas flow rates were identified and sensing temperatures were optimized resulting in a low detection limit of acetone ({approx}20 ppb) with short response (10-15 s) and recovery times (35-70 s). Furthermore, the sensor signal (response) was robust against variations of the exhaled breath flow rate facilitating application of these sensors at realistic relative humidities (80-90%) as in the human breath. The acetone content in the breath of test persons was monitored continuously and compared to that of state-of-the-art proton transfer reaction mass spectrometry (PTR-MS). Such portable devices can accurately track breath acetone concentration to become an alternative to more elaborate breath analysis techniques.

  5. Short Horizon Control Strategies for an Alternating Activated Sludge Process

    DEFF Research Database (Denmark)

    Isaacs, Steven Howard


    Three control strategies allowing improved operational flexibility of an alternating type activated sludge process are presented in a unified model based framework. The control handles employed are the addition rate of an external carbon source to denitrification, the cycle length...

  6. An adaptive breath sampler for use with human subjects with an impaired respiratory function. (United States)

    Basanta, M; Koimtzis, T; Singh, D; Wilson, I; Thomas, C L P


    An adaptive sampler for collecting 2.5 dm(3) samples of exhaled air from human subjects with an impaired respiratory function is described. Pressure in the upper respiratory tract is continuously monitored and the data used to control an automated system to collect select portions of the expired breathing cycle onto a mixed bed Tenax(trade mark) and Carbotrap(trade mark) adsorbent trap for analysis by GC-MS. The sampling approach is intended for use in metabolomic profiling of volatiles in human breath at concentrations greater than microg m(-3). The importance of experimental reproducibility in metabolomic data is emphasised and consequently a high purity air supply is used to maintain a stable exogenous volatile organic compound profile at concentrations in the range 5 to 30 microg m(-3). The results of a 90 day stability study showed that exogenous VOCs were maintained at significantly lower levels (40 times lower for isopropyl alcohol) and with significantly higher reproducibility (80 times lower standard deviation for isopropyl alcohol) than would have been be the case if ambient air had been used. The sampling system was evaluated with healthy controls alongside subjects with chronic obstructive pulmonary disease. Subjects were able to breathe normally with control subjects observed to breathe at a rate of 9 to 17 breaths per minute, compared to 16 to 30 breaths per minute for subjects with COPD. This study presents, for the first time, observations and estimates of intra-subject breath sample reproducibility from human subjects. These reproducibility studies indicated that VOCs in exhaled breath exhibit a variety of dynamic behaviours, with some species recovered with a RSD <30%, while other species were observed to have significantly more variable concentrations, 30 to 130% RSD. The approach was also demonstrated to reliably differentiate the differences in the VOC profiles between alveolar and dead space air.

  7. Active chatter control in a milling machine

    Energy Technology Data Exchange (ETDEWEB)

    Dohner, J.L.; Hinnerichs, T.D.; Lauffer, J.P. [and others


    The use of active feedback compensation to mitigate cutting instabilities in an advanced milling machine is discussed in this paper. A linear structural model delineating dynamics significant to the onset of cutting instabilities was combined with a nonlinear cutting model to form a dynamic depiction of an existing milling machine. The model was validated with experimental data. Modifications made to an existing machine model were used to predict alterations in dynamics due to the integration of active feedback compensation. From simulations, subcomponent requirements were evaluated and cutting enhancements were predicted. Active compensation was shown to enable more than double the metal removal rate over conventional milling machines. 25 refs., 10 figs., 1 tab.

  8. Digitally Controlled ’Programmable’ Active Filters. (United States)


    Mitra, S. K., Analysis and Synthesis of Linear Active .. Networks, Wiley, New York, 1969. * 6. Sedra , A. S. and Smith , K. C., "A Second-Generation...Current Conveyor and its Applications," IEEE Trans. Circuit Theory, Vol. CT-17, pp. 132-134, 1970. 7. Sedra , A. S., "A New Approach to Active Network...CT-18, pp. 358-361, May 1971. 27. Hamilton, T. A., and Sedra , A. S., "Some New IJ Configurations for Active Filters," IEEE Trans. Circuit Tehory, Vol

  9. Controlling postoperative ileus by vagal activation

    Institute of Scientific and Technical Information of China (English)

    Tim; Lubbers; Wim; Buurman; Misha; Luyer


    Postoperative ileus is a frequently occurring surgical complication, leading to increased morbidity and hospital stay. Abdominal surgical interventions are known to result in a protracted cessation of bowel movement. Activation of inhibitory neural pathways by nociceptive stimuli leads to an inhibition of propulsive activity, which resolves shortly after closure of the abdomen. The subsequent formation of an inflammatory infiltrate in the muscular layers of the intestine results in a more prolonged phase of...

  10. Cheyne-Stokes respiration: hypoxia plus a deep breath that interrupts hypoxic drive, initiating cyclic breathing. (United States)

    Guntheroth, Warren G


    In the 19th Century, Cheyne and Stokes independently reported cycles of respiration in patients with heart failure, beginning with apnea, followed by a few breaths. However Cheyne-Stokes respiration (C-SR) can also occur in healthy individuals with sleep, and was demonstrated in 1908 with voluntary hyperventilation, followed by apnea that Haldane blamed on hypoxia, subsequently called post-hyperventilation apnea. Additional theories explaining C-SR did not appear until 1954, based on control theory, specifically a feed-back regulator controlling CO(2). This certainly describes control of normal respiration, but to produce an unstable state such as C-SR requires either a very long transit time (3½ min) or an increase of the controller gain (13 times), physiologically improbable. There is general agreement that apnea initiates C-SR but that has not been well explained except for post-hyperventilation apnea, and that explanation is not compatible with a study by Nielsen and Smith in 1951. They plotted the effects of diminished oxygen on ventilation (V) in relation to CO(2) (Fig. 1). They found that the slope of V/CO(2) (gain) increased with hypoxia, but it flattened at a moderate CO(2) level and had nointercept with zero (apnea). It is also incompatible with our published findings in 1975 that showed that apnea did not occur until an extreme level of hypoxia occurred (the PO(2) fell below 10 mmHg), followed shortly by gasping. Much milder hypoxia underlies most cases of C-SR, when hypoxic drive replaces the normal CO(2)-based respiratory drive, in a failsafe role. I hypothesize that the cause of apnea is a brief interruption of hypoxic drive caused by a pulse of oxygen from a stronger than average breath, such as a sigh. The rapidity of onset of apnea in response to a pulse of oxygen, reflects the large pressure gradient for oxygen from air to lung with each breath, in contrast to CO(2). With apnea, there is a gradual fall in oxygen, resulting in a resumption of

  11. Power active filter control based on a resonant disturbance observer


    Ramos Fuentes, German A.; Cortés Romero, John Alexander; Zou, Zhixiang; Costa Castelló, Ramon; Zhou, Keliang


    Active filters are power electronics devices used to eliminate harmonics from the distribution network. This article presents an active disturbance rejection control scheme for active filters. The controller is based on a linear disturbance observer combined with a disturbance rejection scheme. The parameter tuning is based on a combined pole placement and an optimal estimation based on Kalman-Bucy filter. Proposed scheme is validated through simulation and experimental work in an active filter.

  12. 46 CFR 197.456 - Breathing supply hoses. (United States)


    ... 46 Shipping 7 2010-10-01 2010-10-01 false Breathing supply hoses. 197.456 Section 197.456 Shipping....456 Breathing supply hoses. (a) The diving supervisor shall insure that— (1) Each breathing supply....5 times its maximum working pressure; (2) Each breathing supply hose assembly, prior to being...

  13. 21 CFR 862.3080 - Breath nitric oxide test system. (United States)


    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Breath nitric oxide test system. 862.3080 Section... Systems § 862.3080 Breath nitric oxide test system. (a) Identification. A breath nitric oxide test system is a device intended to measure fractional nitric oxide in human breath. Measurement of changes...

  14. 42 CFR 84.91 - Breathing resistance test; exhalation. (United States)


    ... 42 Public Health 1 2010-10-01 2010-10-01 false Breathing resistance test; exhalation. 84.91...-Contained Breathing Apparatus § 84.91 Breathing resistance test; exhalation. (a) Resistance to exhalation...-circuit apparatus with a breathing machine as described in § 84.88, and the exhalation resistance...

  15. Experimental investigation of active machine tool vibration control (United States)

    Rojas, J.; Liang, Chen; Geng, Zheng J.


    The successful vibration reduction of machine tools during machining process can improve productivity, increase quality, and reduce tool wear. This paper will present our initial investigation in the application of smart material technologies in machine tool vibration control using magnetostrictive actuators and electrorheological elastomer dampers on an industrial Sheldon horizontal lathe. The dynamics of the machining process are first studied, which reveals the complexity in the machine tool vibration response and the challenge to the active control techniques. The active control experiment shows encouraging results. The use of electrorheological elastomer damping device for active/passive vibration control provides significant vibration reduction in the high frequency range and great improvement in the workpiece surface finishing. The research presented in this paper demonstrates that the combination of active and active/passive vibration control techniques is very promising for successful machine tool vibration control.

  16. Active control of radiated sound using nearfield pressure sensing

    Institute of Scientific and Technical Information of China (English)

    CHEN Ke'an; YIN Xuefei


    Based on nearfield sound pressure sensing to pick up error information, an approach for constructing active acoustic structure to effectively reduce radiated sound power at low frequency is proposed. The idea is that a nearfield pressure after active control is used as error signals and transformed into an objective function in adaptive active control process.Firstly sound power expression using near-field pressure radiated from a flexible structure is derived, and then three kind of nearfield pressure based active control strategies, I.e. Minimization of radiated sound power, minimization of sound power for dominant radiation modes and minimization of sound power for modified dominant radiation modes are respectively presented and applied to active control of radiated single and broadband noise. Finally computer simulations on sound power reduction under three strategies are conducted and it is shown that the proposed active control strategies are invalid and considerable reduction in radiated sound power can be achieved.

  17. Respiratory Sinus Arrhythmia as an Index of Vagal Activity during Stress in Infants: Respiratory Influences and Their Control (United States)

    Ritz, Thomas; Bosquet Enlow, Michelle; Schulz, Stefan M.; Kitts, Robert; Staudenmayer, John; Wright, Rosalind J.


    Respiratory sinus arrhythmia (RSA) is related to cardiac vagal outflow and the respiratory pattern. Prior infant studies have not systematically examined respiration rate and tidal volume influences on infant RSA or the extent to which infants' breathing is too fast to extract a valid RSA. We therefore monitored cardiac activity, respiration, and physical activity in 23 six-month old infants during a standardized laboratory stressor protocol. On average, 12.6% (range 0–58.2%) of analyzed breaths were too short for RSA extraction. Higher respiration rate was associated with lower RSA amplitude in most infants, and lower tidal volume was associated with lower RSA amplitude in some infants. RSA amplitude corrected for respiration rate and tidal volume influences showed theoretically expected strong reductions during stress, whereas performance of uncorrected RSA was less consistent. We conclude that stress-induced changes of peak-valley RSA and effects of variations in breathing patterns on RSA can be determined for a representative percentage of infant breaths. As expected, breathing substantially affects infant RSA and needs to be considered in studies of infant psychophysiology. PMID:23300753

  18. Respiratory sinus arrhythmia as an index of vagal activity during stress in infants: respiratory influences and their control.

    Directory of Open Access Journals (Sweden)

    Thomas Ritz

    Full Text Available Respiratory sinus arrhythmia (RSA is related to cardiac vagal outflow and the respiratory pattern. Prior infant studies have not systematically examined respiration rate and tidal volume influences on infant RSA or the extent to which infants' breathing is too fast to extract a valid RSA. We therefore monitored cardiac activity, respiration, and physical activity in 23 six-month old infants during a standardized laboratory stressor protocol. On average, 12.6% (range 0-58.2% of analyzed breaths were too short for RSA extraction. Higher respiration rate was associated with lower RSA amplitude in most infants, and lower tidal volume was associated with lower RSA amplitude in some infants. RSA amplitude corrected for respiration rate and tidal volume influences showed theoretically expected strong reductions during stress, whereas performance of uncorrected RSA was less consistent. We conclude that stress-induced changes of peak-valley RSA and effects of variations in breathing patterns on RSA can be determined for a representative percentage of infant breaths. As expected, breathing substantially affects infant RSA and needs to be considered in studies of infant psychophysiology.

  19. Can Breath Test Detect Stomach Cancers Earlier? (United States)

    ... news/fullstory_163342.html Can Breath Test Detect Stomach Cancers Earlier? New technology may also spot esophageal cancers ... the only way to diagnose esophageal cancer or stomach cancer is with endoscopy. This method is expensive, invasive ...


    Directory of Open Access Journals (Sweden)

    C. Janardan


    Full Text Available Background: Asian Indians have a higher operative and overall increased mortality following coronary bypass surgery. They also have higher rates of post operative complications and repeat surgeries. Apart from physiological complications like post-operative pain, atelectasis, deep vein thrombosis, the psychological disorders are like anxiety and stress also predominantly play a major role in the morbidity of the post-surgical conditions. The aim of study is to know the influence of music therapy and breathing exercises on post-surgical cardiac diseased individuals. To evaluate the influence of music therapy and breathing exercises on physiological parameters(BP,HR,RR in post surgical cardiac diseased individuals by using electro cardio monitor and state-trait anxiety scale. Methods: Subjects were randomly divided into two groups. Experimental group, where the subjects received music therapy and breathing exercises. Control group, where the subjects received breathing exercises. All the participants were assessed with STAI scale and physiological parameters like blood pressure, heart rate and respiration rate for both groups before and after the treatment. Paired sample t-test was used to compare the STAI scale and physiological parameters within the groups. Result: Results showed a significant improvement in both the groups but, more improvement was seen in experimental group compared to control group. Conclusion: Results suggested that music therapy and breathing exercises influences more effective than breathing exercises alone.

  1. Orthogonal Control of Antibacterial Activity with Light

    NARCIS (Netherlands)

    Velema, Willem A.; van der Berg, Jan Pieter; Szymanski, Wiktor; Driessen, Arnold J. M.; Feringa, Ben L.


    Selection of a single bacterial strain out of a mixture of microorganisms is of crucial importance in healthcare and microbiology research. Novel approaches that can externally control bacterial selection are a valuable addition to the microbiology toolbox. In this proof-of-concept, two complementar

  2. Selective Activation and Disengagement of Moral Control. (United States)

    Bandura, Albert


    Analyzes psychological mechanisms by which moral control is selectively disengaged from inhumane conduct in ordinary and unusual circumstances. Explores the symptoms of moral exclusion as described in the literature. Presents categories that unify theory on moral exclusion and contribute practical classifications for use in empirical studies. (JS)

  3. Broadband Radiation Modes: Estimation and Active Control

    NARCIS (Netherlands)

    Berkhoff, Arthur P.


    In this paper we give a formulation of the most efficiently radiating vibration patterns of a vibrating body, the radiation modes, in the time domain. The radiation modes can be used to arrive at efficient weighting schemes for an array of sensors in order to reduce the controller dimensionality. Be

  4. Limited Investigation of Active Feel Control Stick System (Active Stick) (United States)


    at VCORNER .............. 15 Figure 12: Pitch Rate Response to 1.5 g Commanded Force PTI at VHI ......................... 16 Figure 13: Pitch Angle...Response to 1.5 g Commanded Force PTI at VHI ...................... 17 Figure 14: Flight Control System Stick Attributes at VLO...23 Figure 19: Cooper-Harper Ratings for Head Down Display Task ( VHI ) ......................... 24 Figure 20: Fine

  5. Control System Design of Shunt Active Power Filter Based on Active Disturbance Rejection and Repetitive Control Techniques


    Le Ge; Xiaodong Yuan; Zhong Yang


    To rely on joint active disturbance rejection control (ADRC) and repetitive control (RC), in this paper, a compound control law for active power filter (APF) current control system is proposed. According to the theory of ADRC, the uncertainties in the model and from the circumstance outside are considered as the unknown disturbance to the system. The extended state observer can evaluate the unknown disturbance. Next, RC is introduced into current loop to improve the steady characteristics. Th...

  6. Active control of noise radiation from vibrating structures

    DEFF Research Database (Denmark)

    Mørkholt, Jakob

    The thesis is concerned with the active control of randomly vibrating structures by means of feedback control, with particular emphasis on reducing the sound radiation from such structures. A time domain model of the structural and radiation dynamics of an actively controlled plate has been...... developed, based on the theory of radiation filters for estimating the sound radiation from multimodal vibrations. This model has then been used in simulations of optimal feedback control, with special emphasis of the stability margins of the optimal control scheme. Two different methods of designing...... optimal and robust discrete-time feedback controllers for active vibration control of multimodal structures have been compared. They have been showed to yield controllers with identical frequency response characteristics, even though they employ completely different methods of numerical solutions...

  7. Geometric Variational Methods for Controlled Active Vision (United States)


    Kantorovich mass transfer problem,” Numerische Mathematik 84 (2000), pp. 375-393. [14] A. Blake and M. Isard , Active Contours, Springer-Verlag, New York...flow,” Artificial Intelligence, 23:185– 203, 1981. [59] M. Isard and A. Blake, ”CONDENSATION – conditional density propagation for visual tracking

  8. Genetic control of active neural circuits

    Directory of Open Access Journals (Sweden)

    Leon Reijmers


    Full Text Available The use of molecular tools to study the neurobiology of complex behaviors has been hampered by an inability to target the desired changes to relevant groups of neurons. Specific memories and specific sensory representations are sparsely encoded by a small fraction of neurons embedded in a sea of morphologically and functionally similar cells. In this review we discuss genetics techniques that are being developed to address this difficulty. In several studies the use of promoter elements that are responsive to neural activity have been used to drive long lasting genetic alterations into neural ensembles that are activated by natural environmental stimuli. This approach has been used to examine neural activity patterns during learning and retrieval of a memory, to examine the regulation of receptor trafficking following learning and to functionally manipulate a specific memory trace. We suggest that these techniques will provide a general approach to experimentally investigate the link between patterns of environmentally activated neural firing and cognitive processes such as perception and memory.

  9. Optoacoustic 13C-breath test analyzer (United States)

    Harde, Hermann; Helmrich, Günther; Wolff, Marcus


    The composition and concentration of exhaled volatile gases reflects the physical ability of a patient. Therefore, a breath analysis allows to recognize an infectious disease in an organ or even to identify a tumor. One of the most prominent breath tests is the 13C-urea-breath test, applied to ascertain the presence of the bacterium helicobacter pylori in the stomach wall as an indication of a gastric ulcer. In this contribution we present a new optical analyzer that employs a compact and simple set-up based on photoacoustic spectroscopy. It consists of two identical photoacoustic cells containing two breath samples, one taken before and one after capturing an isotope-marked substrate, where the most common isotope 12C is replaced to a large extent by 13C. The analyzer measures simultaneously the relative CO2 isotopologue concentrations in both samples by exciting the molecules on specially selected absorption lines with a semiconductor laser operating at a wavelength of 2.744 μm. For a reliable diagnosis changes of the 13CO2 concentration of 1% in the exhaled breath have to be detected at a concentration level of this isotope in the breath of about 500 ppm.

  10. Understanding the brain by controlling neural activity


    Krug, Kristine; Salzman, C. Daniel; Waddell, Scott


    Causal methods to interrogate brain function have been employed since the advent of modern neuroscience in the nineteenth century. Initially, randomly placed electrodes and stimulation of parts of the living brain were used to localize specific functions to these areas. Recent technical developments have rejuvenated this approach by providing more precise tools to dissect the neural circuits underlying behaviour, perception and cognition. Carefully controlled behavioural experiments have been...

  11. Clinical Applications of CO2 and H2 Breath Test


    ZHAO Si-qian; Chen, Bao-Jun; LUO Zhi-fu


    Breath test is non-invasive, high sensitivity and high specificity. In this article, CO2 breath test, H2 breath test and their clinical applications were elaborated. The main applications of CO2 breath test include helicobacter pylori test, liver function detection, gastric emptying test, insulin resistance test, pancreatic exocrine secretion test, etc. H2 breath test can be applied in the diagnosis of lactose malabsorption and detecting small intestinal bacterial overgrowth. With further res...

  12. Regular, brief mindfulness meditation practice improves electrophysiological markers of attentional control



    Mindfulness-based meditation practices involve various attentional skills, including the ability to sustain and focus ones attention. During a simple mindful breathing practice, sustained attention is required to maintain focus on the breath while cognitive control is required to detect mind wandering. We thus hypothesized that regular, brief mindfulness training would result in improvements in the self-regulation of attention and foster changes in neuronal activity related to attentional con...

  13. Attractor structure discriminates sleep states: recurrence plot analysis applied to infant breathing patterns. (United States)

    Terrill, Philip Ian; Wilson, Stephen James; Suresh, Sadasivam; Cooper, David M; Dakin, Carolyn


    Breathing patterns are characteristically different between infant active sleep (AS) and quiet sleep (QS), and statistical quantifications of interbreath interval (IBI) data have previously been used to discriminate between infant sleep states. It has also been identified that breathing patterns are governed by a nonlinear controller. This study aims to investigate whether nonlinear quantifications of infant IBI data are characteristically different between AS and QS, and whether they may be used to discriminate between these infant sleep states. Polysomnograms were obtained from 24 healthy infants at six months of age. Periods of AS and QS were identified, and IBI data extracted. Recurrence quantification analysis (RQA) was applied to each period, and recurrence calculated for a fixed radius in the range of 0-8 in steps of 0.02, and embedding dimensions of 4, 6, 8, and 16. When a threshold classifier was trained, the RQA variable recurrence was able to correctly classify 94.3% of periods in a test dataset. It was concluded that RQA of IBI data is able to accurately discriminate between infant sleep states. This is a promising step toward development of a minimal-channel automatic sleep state classification system.

  14. An electronic control for an electrohydraulic active control landing gear for the F-4 aircraft (United States)

    Ross, I.


    A controller for an electrohydraulic active control landing gear was developed for the F-4 aircraft. A controller was modified for this application. Simulation results indicate that during landing and rollout over repaired bomb craters the active gear effects a force reduction, relative to the passive gear, or approximately 70%.

  15. Geometric control of active collective motion

    CERN Document Server

    Theillard, Maxime; Saintillan, David


    Recent experimental studies have shown that confinement can profoundly affect self-organization in semi-dilute active suspensions, leading to striking features such as the formation of steady and spontaneous vortices in circular domains and the emergence of unidirectional pumping motions in periodic racetrack geometries. Motivated by these findings, we analyze the two-dimensional dynamics in confined suspensions of active self-propelled swimmers using a mean-field kinetic theory where conservation equations for the particle configurations are coupled to the forced Navier-Stokes equations for the self-generated fluid flow. In circular domains, a systematic exploration of the parameter space casts light on three distinct states: equilibrium with no flow, stable vortex, and chaotic motion, and the transitions between these are explained and predicted quantitatively using a linearized theory. In periodic racetracks, similar transitions from equilibrium to net pumping to traveling waves to chaos are observed in ag...

  16. How does breathing frequency affect the performance of an N95 filtering facepiece respirator and a surgical mask against surrogates of viral particles? (United States)

    He, Xinjian; Reponen, Tiina; McKay, Roy; Grinshpun, Sergey A


    Breathing frequency (breaths/min) differs among individuals and levels of physical activity. Particles enter respirators through two principle penetration pathways: faceseal leakage and filter penetration. However, it is unknown how breathing frequency affects the overall performance of N95 filtering facepiece respirators (FFRs) and surgical masks (SMs) against viral particles, as well as other health-relevant submicrometer particles. A FFR and SM were tested on a breathing manikin at four mean inspiratory flows (MIFs) (15, 30, 55, and 85 L/min) and five breathing frequencies (10, 15, 20, 25, and 30 breaths/min). Filter penetration (Pfilter) and total inward leakage (TIL) were determined for the tested respiratory protection devices against sodium chloride (NaCl) aerosol particles in the size range of 20 to 500 nm. "Faceseal leakage-to-filter" (FLTF) penetration ratios were calculated. Both MIF and breathing frequency showed significant effects (p breathing frequency increased TIL for the N95 FFR whereas no clear trends were observed for the SM. Increasing MIF increased Pfilter and decreased TIL resulting in decreasing FLTF ratio. Most of FLTF ratios were >1, suggesting that the faceseal leakage was the primary particle penetration pathway at various breathing frequencies. Breathing frequency is another factor (besides MIF) that can significantly affect the performance of N95 FFRs, with higher breathing frequencies increasing TIL. No consistent trend of increase or decrease of TIL with either MIF or breathing frequency was observed for the tested SM. To potentially extend these findings beyond the manikin/breathing system used, future studies are needed to fully understand the mechanism causing the breathing frequency effect on the performance of respiratory protection devices on human subjects.

  17. Controllability and hippocampal activation during pain expectation in fibromyalgia syndrome. (United States)

    González-Roldán, Ana María; Bomba, Isabelle C; Diesch, Eugen; Montoya, Pedro; Flor, Herta; Kamping, Sandra


    To examine the role of perceived control in pain perception, fibromyalgia patients and healthy controls participated in a reaction time experiment under different conditions of pain controllability. No significant differences between groups were found in pain intensity and unpleasantness ratings. However, during the expectation of uncontrollable pain, patients compared to controls showed higher hippocampal activation. In addition, hippocampal activity during the pain expectation period predicted activation of the posterior cingulate cortex (PCC), precuneus and hippocampus during pain stimulation in fibromyalgia patients. The increased activation of the hippocampus during pain expectation and subsequent activation of the PCC/precuneus during the lack of control phase points towards an influence of pain perception through heightening of alertness and anxiety responses to pain in fibromyalgia patients.

  18. Linear Quadratic Integral Control for the Active Suspension of Vehicle

    Institute of Scientific and Technical Information of China (English)


    The quarter model of an active suspension is established in the form of controllable autoregressive moving average (CARMA) model. An accelerometer can be mounted on the wheel hub for measuring road disturbance; this signal is used to identify the CARMA model parameters by recursive forgetting factors least square method. The linear quadratic integral (LQI) control method for the active suspension is presented. The LQI control algorithm is fit for vehicle suspension control, for the control performance index can comprise multi controlled variables. The simulation results show that the vertical acceleration and suspension travel both are decreased with the LQI control in the low frequency band, and the suspension travel is increased with the LQI control in the middle or high frequency band. The suspension travel is very small in the middle or high frequency band, the suspension bottoming stop will not happen, so the vehicle ride quality can be improved apparently by the LQI control.

  19. Active Disturbance Rejection Control of a Heat Integrated Distillation Column

    DEFF Research Database (Denmark)

    Al-Kalbani, Fahad; Zhang, Jie; Bisgaard, Thomas;


    pressure. However, the control of some HiDC processesis generally difficult due to the strong control loop interaction, high purity of the components and undesired disturbances. Active disturbance rejection control (ADRC) is used in this paperto control a simulated HiDC for separating benzene......-toluene mixture. The efficiency of the ADRC technique is demonstrated by comparing with the conventional PI controller in terms of set-point trackingand external disturbance rejection capability. The results show that the ADRC gives much improved control performance than the PID control....

  20. Orthogonal control of antibacterial activity with light. (United States)

    Velema, Willem A; van der Berg, Jan Pieter; Szymanski, Wiktor; Driessen, Arnold J M; Feringa, Ben L


    Selection of a single bacterial strain out of a mixture of microorganisms is of crucial importance in healthcare and microbiology research. Novel approaches that can externally control bacterial selection are a valuable addition to the microbiology toolbox. In this proof-of-concept, two complementary antibiotics are protected with photocleavable groups that can be orthogonally addressed with different wavelengths of light. This allows for the light-triggered selection of a single bacterial strain out of a mixture of multiple strains, by choosing the right wavelength. Further improvement toward additional orthogonally addressable antibiotics might ultimately lead to a novel methodology for bacterial selection in complex populations.

  1. Neuro-fuzzy based Controller for Solving Active Power Filter

    Directory of Open Access Journals (Sweden)

    Homayoun Ebrahimian


    Full Text Available In this paper, two soft computing techniques by fuzzy logic, neural network are used to design alternative control schemes for switching the APF active power filter (APF. The control of a shunt active power filter designed for harmonic and reactive current mitigation. Application of the mentioned model has been combined by an intelligent algorithm for improving the efficiency of proposed controller. Effectiveness of the proposed method has been applied over test case and shows the validity of proposed model.

  2. Analysis of Breath Specimens for Biomarkers of Plasmodium falciparum Infection. (United States)

    Berna, Amalia Z; McCarthy, James S; Wang, Rosalind X; Saliba, Kevin J; Bravo, Florence G; Cassells, Julie; Padovan, Benjamin; Trowell, Stephen C


    Currently, the majority of diagnoses of malaria rely on a combination of the patient's clinical presentation and the visualization of parasites on a stained blood film. Breath offers an attractive alternative to blood as the basis for simple, noninvasive diagnosis of infectious diseases. In this study, breath samples were collected from individuals during controlled malaria to determine whether specific malaria-associated volatiles could be detected in breath. We identified 9 compounds whose concentrations varied significantly over the course of malaria: carbon dioxide, isoprene, acetone, benzene, cyclohexanone, and 4 thioethers. The latter group, consisting of allyl methyl sulfide, 1-methylthio-propane, (Z)-1-methylthio-1-propene, and (E)-1-methylthio-1-propene, had not previously been associated with any disease or condition. Before the availability of antimalarial drug treatment, there was evidence of concurrent 48-hour cyclical changes in the levels of both thioethers and parasitemia. When thioether concentrations were subjected to a phase shift of 24 hours, a direct correlation between the parasitemia and volatile levels was revealed. Volatile levels declined monotonically approximately 6.5 hours after initial drug treatment, correlating with clearance of parasitemia. No thioethers were detected in in vitro cultures of Plasmodium falciparum. The metabolic origin of the thioethers is not known, but results suggest that interplay between host and parasite metabolic pathways is involved in the production of these thioethers.

  3. An active control synchronization for two modified Chua circuits

    Institute of Scientific and Technical Information of China (English)

    Li Guo-Hui


    From modern control theory, an active control method to synchronize two modified Chua circuits with each other, which exhibit chaos, is presented. Some sufficient conditions of linear stability of the chaotic synchronization are obtained from rigorous mathematic justification. On the basis of the state-observer, the controller is analytically deduced using the active control. It is shown that this technique can be applied to achieve synchroniztion of the tow systems with each other, whether they are identical or not. Finally, numerical simulations show the effectiveness of the proposed control scheme.

  4. Experience with ActiveX control for simple channel access

    Energy Technology Data Exchange (ETDEWEB)

    Timossi, C.; Nishimura, H.; McDonald, J.


    Accelerator control system applications at Berkeley Lab's Advanced Light Source (ALS) are typically deployed on operator consoles running Microsoft Windows 2000 and utilize EPICS[2]channel access for data access. In an effort to accommodate the wide variety of Windows based development tools and developers with little experience in network programming, ActiveX controls have been deployed on the operator stations. Use of ActiveX controls for use in the accelerator control environment has been presented previously[1]. Here we report on some of our experiences with the use and development of these controls.

  5. Fault tolerant control based on active fault diagnosis

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik


    An active fault diagnosis (AFD) method will be considered in this paper in connection with a Fault Tolerant Control (FTC) architecture based on the YJBK parameterization of all stabilizing controllers. The architecture consists of a fault diagnosis (FD) part and a controller reconfiguration (CR...


    Institute of Scientific and Technical Information of China (English)

    Wang Qingfeng; Zhao Ju; Yang Botao


    A statistic linearization analysis method of bad nolinear hydraulic active damping suspensiop is provided.Also the optimum control strategy of semi-active suspension and graded control strategy based on it are puted forward.Experimental researches are carried out on a 2 DOF (degree of freedom ) hydraulic active damping suspension test system.The results showed that an excellent control effectiveness could be obtained by using statistic linearization optimum control which unfortunely requests continuously regulationg the damp in an accurate way and costs much in engeering application.On the contrary,the results also showed that graded control is more practicable which has a control effectiveness close to the optimum control and costs less.

  7. Enhancing Sensorimotor Activity by Controlling Virtual Objects with Gaze



    This fMRI work studies brain activity of healthy volunteers who manipulated a virtual object in the context of a digital game by applying two different control methods: using their right hand or using their gaze. The results show extended activations in sensorimotor areas, not only when participants played in the traditional way (using their hand) but also when they used their gaze to control the virtual object. Furthermore, with the exception of the primary motor cortex, regional motor activ...

  8. Clinical and Laboratory Findings of Patients with Breath Holding Spells

    Directory of Open Access Journals (Sweden)

    Özlem Özdemir


    Full Text Available Aim: The aim of this prospective study was to evaluate the clinical characteristics; physical findings, cardiological, hematological and neurological problems; treatment approaches; and the prognosis of children with breath holding spells.Materials and Method: Seventhy patients were included in this study. All patients were evaluated with detailed history and physical examination. Complete blood count, serum iron and iron binding capacity were studied; cardiological (telecardiography, electrocardiography, if necessary echocardiography and event recorder and neurological investigations (electroencephalography were done during the admission. Patients with iron deficiency anemia and iron deficiency were treated with ferrous sulphate orally. In patients with normal hematological values, no medication was used. After a two-month treatment period patients underwent control hematological evaluation. Frequency of the spells, age of disappearance of spells (defined as 6 months without spells, disappearance ratios between the three groups were compared. Results: The percentage of cyanotic, palloric and mixt type of breath holding spells of 70 patients included in the study were 67.1, 14.3 and 18.6, respectively. It was determined that psychogenic factors played a role in 77.1% of our patients. There were iron deficiency anemia in 39 (55.7%, iron deficiency in 12 (17.2% and normal hematological parameters in 19 (27.1% of 70 patients. The QTc values were normal in all of them. EEG’s were normal in 56 (80%, dysrhythmic in 11 (15.7% and pathologic in (4.3%. There was a positive family history of breath holding spells in 44.3% of those with breath holding spells. Conclusion: We determined that there was a correlation between the iron levels and the frequency of spells. The lower the iron levels the higher the frequency of spells. There was a dramatic decrease of 92% in spells with low doses of iron supplementation especially in the anemic group. (Journal of

  9. Active control system for high speed windmills (United States)

    Avery, D.E.


    A pump stroke is matched to the operating speed of a high speed windmill. The windmill drives a hydraulic pump for a control. Changes in speed of a wind driven shaft open supply and exhaust valves to opposite ends of a hydraulic actuator to lengthen and shorten an oscillating arm thereby lengthening and shortening the stroke of an output pump. Diminishing wind to a stall speed causes the valves to operate the hydraulic cylinder to shorten the oscillating arm to zero. A pressure accumulator in the hydraulic system provides the force necessary to supply the hydraulic fluid under pressure to drive the actuator into and out of the zero position in response to the windmill shaft speed approaching and exceeding windmill stall speed. 4 figs.

  10. Distributed Model Predictive Control for Active Power Control of Wind Farm

    DEFF Research Database (Denmark)

    Zhao, Haoran; Wu, Qiuwei; Rasmussen, Claus Nygaard;


    This paper presents the active power control of a wind farm using the Distributed Model Predictive Controller (D- MPC) via dual decomposition. Different from the conventional centralized wind farm control, multiple objectives such as power reference tracking performance and wind turbine load can......-scale wind farm control....

  11. Breathing guidance in radiation oncology and radiology: A systematic review of patient and healthy volunteer studies

    Energy Technology Data Exchange (ETDEWEB)

    Pollock, Sean, E-mail:; Keall, Paul [Radiation Physics Laboratory, University of Sydney, Sydney 2050 (Australia); Keall, Robyn [Central School of Medicine, University of Sydney, Sydney 2050, Australia and Hammond Care, Palliative Care and Supportive Care Service, Greenwich 2065 (Australia)


    Purpose: The advent of image-guided radiation therapy has led to dramatic improvements in the accuracy of treatment delivery in radiotherapy. Such advancements have highlighted the deleterious impact tumor motion can have on both image quality and radiation treatment delivery. One approach to reducing tumor motion irregularities is the use of breathing guidance systems during imaging and treatment. These systems aim to facilitate regular respiratory motion which in turn improves image quality and radiation treatment accuracy. A review of such research has yet to be performed; it was therefore their aim to perform a systematic review of breathing guidance interventions within the fields of radiation oncology and radiology. Methods: From August 1–14, 2014, the following online databases were searched: Medline, Embase, PubMed, and Web of Science. Results of these searches were filtered in accordance to a set of eligibility criteria. The search, filtration, and analysis of articles were conducted in accordance with preferred reporting items for systematic reviews and meta-analyses. Reference lists of included articles, and repeat authors of included articles, were hand-searched. Results: The systematic search yielded a total of 480 articles, which were filtered down to 27 relevant articles in accordance to the eligibility criteria. These 27 articles detailed the intervention of breathing guidance strategies in controlled studies assessing its impact on such outcomes as breathing regularity, image quality, target coverage, and treatment margins, recruiting either healthy adult volunteers or patients with thoracic or abdominal lesions. In 21/27 studies, significant (p < 0.05) improvements from the use of breathing guidance were observed. Conclusions: There is a trend toward the number of breathing guidance studies increasing with time, indicating a growing clinical interest. The results found here indicate that further clinical studies are warranted that quantify the

  12. Time-varying respiratory system elastance: a physiological model for patients who are spontaneously breathing.

    Directory of Open Access Journals (Sweden)

    Yeong Shiong Chiew

    Full Text Available BACKGROUND: Respiratory mechanics models can aid in optimising patient-specific mechanical ventilation (MV, but the applications are limited to fully sedated MV patients who have little or no spontaneously breathing efforts. This research presents a time-varying elastance (E(drs model that can be used in spontaneously breathing patients to determine their respiratory mechanics. METHODS: A time-varying respiratory elastance model is developed with a negative elastic component (E(demand, to describe the driving pressure generated during a patient initiated breathing cycle. Data from 22 patients who are partially mechanically ventilated using Pressure Support (PS and Neurally Adjusted Ventilatory Assist (NAVA are used to investigate the physiology relevance of the time-varying elastance model and its clinical potential. E(drs of every breathing cycle for each patient at different ventilation modes are presented for comparison. RESULTS: At the start of every breathing cycle initiated by patient, E(drs is 25 cmH2Os/l and thus can be used as an acute respiratory distress syndrome (ARDS severity indicator. CONCLUSION: The E(drs model captures unique dynamic respiratory mechanics for spontaneously breathing patients with respiratory failure. The model is fully general and is applicable to both fully controlled and partially assisted MV modes.

  13. Active structural control with stable fuzzy PID techniques

    CERN Document Server

    Yu, Wen


    This book presents a detailed discussion of intelligent techniques to measure the displacement of buildings when they are subjected to vibration. It shows how these techniques are used to control active devices that can reduce vibration 60–80% more effectively than widely used passive anti-seismic systems. After introducing various structural control devices and building-modeling and active structural control methods, the authors propose offset cancellation and high-pass filtering techniques to solve some common problems of building-displacement measurement using accelerometers. The most popular control algorithms in industrial settings, PD/PID controllers, are then analyzed and then combined with fuzzy compensation. The stability of this combination is proven with standard weight-training algorithms. These conditions provide explicit methods for selecting PD/PID controllers. Finally, fuzzy-logic and sliding-mode control are applied to the control of wind-induced vibration. The methods described are support...


    Institute of Scientific and Technical Information of China (English)


    A new control scheme, the hybrid fuzzy control method, for active damping suspension system is presented. The scheme is the result of effective combination of the statistical optimal control method based on the statistical property of suspension system, with the bang-bang control method based on the real-time characteristics of suspension system. Computer simulations are performed to compare the effectiveness of hybrid fuzzy control scheme with that of optimal damping control, bang-bang control, and passive suspension. It takes the effects of time-variant factors into full account. The superiority of the proposed hybrid fuzzy control scheme for active damping suspension to the passive suspension is verified in the experiment study.

  15. sup 14 C-urea breath test for the detection of Helicobacter pylori

    Energy Technology Data Exchange (ETDEWEB)

    Veldhuyzen van Zanten, S.J.; Tytgat, K.M.; Hollingsworth, J.; Jalali, S.; Rshid, F.A.; Bowen, B.M.; Goldie, J.; Goodacre, R.L.; Riddell, R.H.; Hunt, R.H. (McMaster Univ., Hamilton, Ontario (Canada))


    The high urease activity of Helicobacter pylori can be used to detect this bacterium by noninvasive breath tests. We have developed a {sup 14}C-urea breath test which uses 5 microCi {sup 14}C with 50 mg nonradioactive urea. Breath samples are collected at baseline and every 30 min for 2 h. Our study compared the outcome of the breath test to the results of histology and culture of endoscopically obtained gastric biopsies in 84 patients. The breath test discriminated well between the 50 positive patients and the 34 patients negative for Helicobacter pylori: the calculated sensitivity was 100%, specificity 88%, positive predictive value 93%, and negative predictive value 100%. Treatment with bismuth subsalicylate and/or ampicillin resulted in lower counts of exhaled {sup 14}CO{sub 2} which correlated with histological improvement in gastritis. The {sup 14}C-urea breath test is a better gold standard for the detection of Helicobacter pylori than histology and/or culture.

  16. Adaptive Current Control with PI-Fuzzy Compound Controller for Shunt Active Power Filter

    Directory of Open Access Journals (Sweden)

    Juntao Fei


    Full Text Available An adaptive control technology and PI-fuzzy compound control technology are proposed to control an active power filter (APF. AC side current compensation and DC capacitor voltage tracking control strategy are discussed and analyzed. Model reference adaptive controller for the AC side current compensation is derived and established based on Lyapunov stability theory; proportional and integral (PI fuzzy compound controller is designed for the DC side capacitor voltage control. The adaptive current controller based on PI-fuzzy compound system is compared with the conventional PI controller for active power filter. Simulation results demonstrate the feasibility and satisfactory performance of the proposed control strategies. It is shown that the proposed control method has an excellent dynamic performance such as small current tracking error, reduced total harmonic distortion (THD, and strong robustness in the presence of parameters variation and nonlinear load.

  17. Numerical evaluation of the performance of active noise control systems (United States)

    Mollo, C. G.; Bernhard, R. J.


    This paper presents a generalized numerical technique for evaluating the optimal performance of active noise controllers. In this technique, the indirect BEM numerical procedures are used to derive the active noise controllers for optimal control of enclosed harmonic sound fields where the strength of the noise sources or the description of the enclosure boundary may not be known. The performance prediction for a single-input single-output system is presented, together with the analysis of the stability and observability of an active noise-control system employing detectors. The numerical procedures presented can be used for the design of both the physical configuration and the electronic components of the optimal active noise controller.

  18. Various applications of Active Field Control (AFC) (United States)

    Watanabe, Takayuki; Miyazaki, Hideo; Kishinaga, Shinji; Kawakami, Fukushi


    AFC is an electro-acoustic enhancement system, which has been under development at Yamaha Corporation. In this paper, several types of various AFC applications are discussed, while referring to representative projects for each application in Japan. (1) Realization of acoustics in a huge hall to classical music program, e.g., Tokyo International Forum. This venue is a multipurpose hall with approximately 5000 seats. AFC achieves loudness and reverberance equivalent to those of a hall with 2500 seats or fewer. (2) Optimization of acoustics for a variety of programs, e.g., Arkas Sasebo. AFC is used to create the optimum acoustics for each program, such as reverberance for classical concerts, acoustical support for opera singers, uniformity throughout the hall from the stage to under-balcony area, etc. (3) Control of room shape acoustical effect, e.g., Osaka Central Public Hall: In this renovation project, preservation of historically important architecture in the original form is required. AFC is installed to vary only the acoustical environment without architectural changes. (4) Assistance with crowd enthusiasm for sports entertainment, e.g., Tokyo Metropolitan Gymnasium. In this venue, which is designed as a very absorptive space for speech intelligibility, AFC is installed to enhance the atmosphere of live sports entertainment.

  19. The influence of breathing type, expiration and cervical posture on the performance of the cranio-cervical flexion test in healthy subjects. (United States)

    Cagnie, Barbara; Danneels, Lieven; Cools, Ann; Dickx, Nele; Cambier, Dirk


    The cranio-cervical flexion test (CCF-T) is used as a clinical evaluation tool for the deep cervical flexors (DCF). The influence of breathing type, expiration and cervical posture on the performance of the test is evaluated in asymptomatic subjects. Thirty volunteers participated in the study and were classified according to their breathing type: costo-diaphragmatic breathing type and upper costal breathing type. Sternocleidomastoid (SCM) electromyographic (EMG) activity was recorded during five incremental levels of CCF during normal breathing as well as during expiration. The cranio-vertebral angle of each subject was measured to quantify cervical posture. During normal inspiration, higher EMG activity of the SCM muscles was observed in subjects with an upper costal breathing pattern compared to costo-diaphragmatic breathing subjects. This difference was statistically significant (Pangle and the EMG activity of the SCM muscles. Performing the CCF-T during slow expiration diminishes the activity of the SCM muscles in subjects with a predominantly upper costal breathing pattern. Using a costo-diaphragmatic breathing pattern while performing the test will optimize the performance. Studies on neck pain patients are required to further clarify this issue.

  20. CLP activities and control in Ireland

    Directory of Open Access Journals (Sweden)

    Caroline Walsh


    Full Text Available The 10th December 2010 marked a new beginning for Regulation (EC no. 1272/2008 on the classification, labelling and packaging of substances and mixtures (CLP in Ireland with the start of its operational phase. It was on this date that the administrative and enforcement provisions for CLP were encompassed in the new Chemicals Amendment Act, 2010. In this Act, the Health and Safety Authority, known as the "the Authority" is named as Competent Authority (CA for CLP, along with the Minister for Agriculture, Fisheries and Food, in respect of pesticides and plant protection products and the Beaumont Hospital Board with responsibility for receiving information relating to emergency health response. In practice, the Authority has been de facto CA for CLP since its publication on the 31st December 2008, given its role in existing classification and labelling regimes. This article focuses on the work undertaken by the Authority on CLP at a National, European and International level including its implementation, training, helpdesk, guidance, enforcement and awareness raising activities.

  1. CLP activities and control in Ireland. (United States)

    Walsh, Caroline


    The 10(th) December 2010 marked a new beginning for Regulation (EC) no. 1272/2008 on the classification, labelling and packaging of substances and mixtures (CLP) in Ireland with the start of its operational phase. It was on this date that the administrative and enforcement provisions for CLP were encompassed in the new Chemicals Amendment Act, 2010. In this Act, the Health and Safety Authority, known as the "the Authority" is named as Competent Authority (CA) for CLP, along with the Minister for Agriculture, Fisheries and Food, in respect of pesticides and plant protection products and the Beaumont Hospital Board with responsibility for receiving information relating to emergency health response. In practice, the Authority has been de facto CA for CLP since its publication on the 31(st) December 2008, given its role in existing classification and labelling regimes. This article focuses on the work undertaken by the Authority on CLP at a National, European and International level including its implementation, training, helpdesk, guidance, enforcement and awareness raising activities.

  2. Active Noise Feedback Control Using a Neural Network

    Directory of Open Access Journals (Sweden)

    Zhang Qizhi


    Full Text Available The active noise control (ANC is discussed. Many digital ANC systems often based on the filter-x algorithm for finite impulse response (FIR filter use adaptive filtering techniques. But if the primary noise path is nonlinear, the control system based on adaptive filter technology will be invalid. In this paper, an adaptive active nonlinear noise feedback control approach using a neural network is derived. The feedback control system drives a secondary signal to destructively interfere with the original noise to cut down the noise power. An on-line learning algorithm based on the error gradient descent method was proposed, and the local stability of closed loop system is proved using the discrete Lyapunov function. A nonlinear simulation example shows that the adaptive active noise feedback control method based on a neural network is very effective to the nonlinear noise control.

  3. On-line Monitoring and Active Control for Transformer Noise (United States)

    Liang, Jiabi; Zhao, Tong; Tian, Chun; Wang, Xia; He, Zhenhua; Duan, Lunfeng

    This paper introduces the system for on-line monitoring and active noise control towards the transformer noise based on LabVIEW and the hardware equipment including the hardware and software. For the hardware part, it is mainly focused on the composition and the role of hardware devices, as well as the mounting location in the active noise control experiment. And the software part introduces the software flow chats, the measurement and analysis module for the sound pressure level including A, B, C weighting methods, the 1/n octave spectrum and the power spectrum, active noise control module and noise data access module.

  4. Lung cancer biomarkers in exhaled breath. (United States)

    Amann, Anton; Corradi, Massimo; Mazzone, Peter; Mutti, Antonio


    Lung cancer is the leading cause of cancer-related mortality worldwide. Methods for early detection of lung cancer, such as computerized tomography scanning technology, often discover a large number of small lung nodules, posing a new problem to radiologists and chest physicians. The vast majority of these nodules will be benign, but there is currently no easy way to determine which nodules represent very early lung cancer. Adjuvant testing with PET imaging and nonsurgical biopsies has a low yield for these small indeterminate nodules, carries potential morbidity and is costly. Indeed, purely morphological criteria seem to be insufficient for distinguishing lung cancer from benign nodules at early stages with sufficient confidence, therefore false positives undergoing surgical resection frequently occur. A molecular approach to the diagnosis of lung cancer through the analysis of exhaled breath could greatly improve the specificity of imaging procedures. A biomarker-driven approach to signs or symptoms possibly due to lung cancer would represent a complementary tool aimed at ruling out (with known error probability) rather than diagnosing lung cancer. Volatile and nonvolatile components of the breath are being studied as biomarkers of lung cancer. Breath testing is noninvasive and potentially inexpensive. There is promise that an accurate lung cancer breath biomarker, capable of being applied clinically, will be developed in the near future. In this article, we summarize some of the rationale for breath biomarker development, review the published literature in this field and provide thoughts regarding future directions.

  5. Indirect control of a single-phase active power filter

    Directory of Open Access Journals (Sweden)

    Mihai CULEA


    Full Text Available The control of shunt active power filters using PWM inverters consists in generating a reference by separating, using different methods, the harmonics to be eliminated. The methods used are time-consuming and need dedicated control and signal processing equipments. To avoid these setbacks a new method is proposed in the paper. The active power filter is a current PWM rectifier with voltage output and with a capacitor on the DC side. The PWM rectifier is controlled so that the sum of its current and the load’s current is a sinusoid. The control block as well as simulation results are presented.

  6. Development of Active Noise Control System for Quieting Transformer Noise

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Bok Kyu; Song, Seik Young; Choi, Huo Yul [Korea Electric Power Research Institute, Taejon (Korea, Republic of); Yun, Dae Hea; Lee, Hyuk Jae [Korea Electrotechnology Research Institute, Changwon (Korea, Republic of)


    The passive noise control technique made use of sound-absorbing or soundproofing materials, so it required a large area and high cost for installation and had a drawback of poor performance at low frequency. Compared to this, the Active Noise Control attenuates noise sound pressure by using secondary source which has same performance ay low-frequency. Furthermore, it is able to save space and expenses. - research on adaptive algorithms - evaluation of global attenuation of the control - computer simulation - real-time Active Noise Control System Hardware Implementation - ANC system setting in the noisy area.

  7. Experimental active control results from the SPICES smart structure demonstrations (United States)

    Flamm, David S.; Toth, G. K.; Chou, Kenneth C.; Heck, Larry P.; Nowlin, William C.; Titterton, Paul J., Sr.


    The final demonstrations of the ARPA SPICES (Synthesis and Processing of Intelligent Cost Effective Structures) program test the control of two active vibration mounts manufactured from composites with embedded actuators and sensors. Both mount demonstrations address wide band control problems for real disturbances, one at low frequency and the other at high frequency. The control systems for both are two-level hierarchies, with an inner active damping augmentation loop and an outer vibration control loop. We first review the control design requirements for the demonstration and summarize our control design approach. Then we focus on presenting the experimental results of the final demonstrations. For the low frequency demonstration, two alternative control approaches were demonstrated, one involving finite impulse response modeling and the other state space modeling. For the high frequency demonstration only the finite impulse response modeling approach was used because of computational limitations due to the complex system dynamics.

  8. Self-assembled breath figure arrays of conjugated conducting polymers for photovoltaic application (United States)

    Routh, Prahlad Kumar; Venkatesh, T. A.; Cotlet, Mircea


    Ordered microporous polymer structures have potential application in catalysis, surface engineering and optoelectronics. The Breath Figure Technique (BFT) is a simple method of producing such ordered microporous structures. In this study BFT was applied to a series of commercial conjugated polymer polythiophene derivatives with varying side chain length (n =6,8,10,12). An in-depth study of processing parameters has been carried with the aim of controlling the morphology of the honeycomb film over large, PV relevant areas. Structural and spectroscopic characterization of honeycomb films were performed using Scanning Electron Microscopy (SEM), X-ray scattering, Fluorescence Lifetime Imaging (FLIM) and Spectroscopy. Blends of these polymers with a fullerene derivative, PCBM, were also subjected to BFT and characterized with similar methods to assess their potential use as active layers in PV solar cells. Center for Functional Nanomaterials, Brookhaven National Laboratory.

  9. The therapeutic dilemma of vagus nerve stimulator-induced sleep disordered breathing (United States)

    Upadhyay, Hinesh; Bhat, Sushanth; Gupta, Divya; Mulvey, Martha; Ming, Sue


    Intermittent vagus nerve stimulation (VNS) can reduce the frequency of seizures in patients with refractory epilepsy, but can affect respiration in sleep. Untreated obstructive sleep apnea (OSA) can worsen seizure frequency. Unfortunately, OSA and VNS-induced sleep disordered breathing (SDB) may occur in the same patient, leading to a therapeutic dilemma. We report a pediatric patient in whom OSA improved after tonsillectomy, but coexistent VNS-induced SDB persisted. With decrease in VNS output current, patient's SDB improved, but seizure activity exacerbated, which required a return to the original settings. Continuous positive airway pressure titration was attempted, which showed only a partial improvement in apnea–hypopnea index. This case illustrates the need for clinicians to balance seizure control and SDB in patients with VNS. PMID:27168865

  10. Light-Activated Ion Channels for Remote Control of Neural Activity


    Chambers, James J.; Richard H Kramer


    Light-activated ion channels provide a new opportunity to precisely and remotely control neuronal activity for experimental applications in neurobiology. In the past few years, several strategies have arisen that allow light to control ion channels and therefore neuronal function. Light-based triggers for ion channel control include caged compounds, which release active neurotransmitters when photolyzed with light, and natural photoreceptive proteins, which can be expressed exogenously in neu...

  11. Adaptive Current Control Method for Hybrid Active Power Filter (United States)

    Chau, Minh Thuyen


    This paper proposes an adaptive current control method for Hybrid Active Power Filter (HAPF). It consists of a fuzzy-neural controller, identification and prediction model and cost function. The fuzzy-neural controller parameters are adjusted according to the cost function minimum criteria. For this reason, the proposed control method has a capability on-line control clings to variation of the load harmonic currents. Compared to the single fuzzy logic control method, the proposed control method shows the advantages of better dynamic response, compensation error in steady-state is smaller, able to online control is better and harmonics cancelling is more effective. Simulation and experimental results have demonstrated the effectiveness of the proposed control method.

  12. Active Disturbance Rejection Approach for Robust Fault-Tolerant Control via Observer Assisted Sliding Mode Control

    Directory of Open Access Journals (Sweden)

    John Cortés-Romero


    Full Text Available This work proposes an active disturbance rejection approach for the establishment of a sliding mode control strategy in fault-tolerant operations. The core of the proposed active disturbance rejection assistance is a Generalized Proportional Integral (GPI observer which is in charge of the active estimation of lumped nonlinear endogenous and exogenous disturbance inputs related to the creation of local sliding regimes with limited control authority. Possibilities are explored for the GPI observer assisted sliding mode control in fault-tolerant schemes. Convincing improvements are presented with respect to classical sliding mode control strategies. As a collateral advantage, the observer-based control architecture offers the possibility of chattering reduction given that a significant part of the control signal is of the continuous type. The case study considers a classical DC motor control affected by actuator faults, parametric failures, and perturbations. Experimental results and comparisons with other established sliding mode controller design methodologies, which validate the proposed approach, are provided.

  13. Development of hydraulic brake actuator for active brake control; Active brake seigyoyo yuatsu booster no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Konishi, Y.; Hattori, M. Sugisawa, M.; Nishii, M. [Aisin Seiki Co. Ltd., Aichi (Japan)


    Recently, application of active brake control systems of the vehicle are increasing. (Vehicle stability control, Panic brake assist ) We have developed a new hydraulic brake actuator for active brake control systems. New hydraulic brake actuator is composed of the three parts. (Hydraulic booster unit, Power supply unit, Control valve unit) This report describes the construction of the new hydraulic booster unit. 2 refs., 10 figs.

  14. Technologies for Clinical Diagnosis Using Expired Human Breath Analysis

    Directory of Open Access Journals (Sweden)

    Thalakkotur Lazar Mathew


    Full Text Available This review elucidates the technologies in the field of exhaled breath analysis. Exhaled breath gas analysis offers an inexpensive, noninvasive and rapid method for detecting a large number of compounds under various conditions for health and disease states. There are various techniques to analyze some exhaled breath gases, including spectrometry, gas chromatography and spectroscopy. This review places emphasis on some of the critical biomarkers present in exhaled human breath, and its related effects. Additionally, various medical monitoring techniques used for breath analysis have been discussed. It also includes the current scenario of breath analysis with nanotechnology-oriented techniques

  15. Active Vibration Control of a Monopile Offshore Structure

    DEFF Research Database (Denmark)

    Nielsen, Søren R. K.; Kirkegaard, Poul Henning; Thesbjerg, L.


    , it can be necessary to use an active or a passive vibration control system. However, for a monopile with severe space problems it can be difficult to locate a passive control system such as e.g. a tuned mass damper. Therefore, in order to active control wave introduced vibrations of a monopile structure...... platforms have been developed for approximately 35 m water depth and to be remotely operated. However, there has recently been a wish to use the monopile concept on 75 m water depth. Using monopiles in such water depths can imply significantly dynamic problems. Therefore, in order to reduce the vibrations...... an active control technique has been proposed in corporation with the consulting company Rambøll, Esbjerg, Denmark. The proposed control technique is based on the relationship between the position of the separation points of the boundary layer flow and the drag term in the wave force on the cylinder...

  16. Perception Neural Networks for Active Noise Control Systems

    Directory of Open Access Journals (Sweden)

    Wang Xiaoli


    Full Text Available In a response to a growing demand for environments of 70dB or less noise levels, many industrial sectors have focused with some form of noise control system. Active noise control (ANC has proven to be the most effective technology. This paper mainly investigates application of neural network on self-adaptation system in active noise control (ANC. An active silencing control system is made which adopts a motional feedback loudspeaker as not a noise controlling source but a detecting sensor. The working fundamentals and the characteristics of the motional feedback loudspeaker are analyzed in detail. By analyzing each acoustical path, identification based adaptive linear neural network is built. This kind of identifying method can be achieved conveniently. The estimated result of each sound channel matches well with its real sound character, respectively.

  17. Improved Control Strategy for Active Bouncers used in Klystron Modulators

    CERN Document Server

    Aguglia, D; Benedetti, M; Garcia Retegui, R; Maestri, S; Nisbet, D


    This paper introduces a closed-loop control system for klystron modulators. The system is based on the discharge of a capacitor into a step-up voltage transformer and an active bouncer implemented with a multiphase buck converter. In order to obtain a constant Klystron voltage at the at-top, the active bouncer must compensate both the capacitor discharge and the pulse transformer characteristic. The proposed control includes an inner voltage regulation loop that controls the active bouncer output voltage and an outer one that controls the klystron voltage. The primary side current and main capacitor voltage are included in the regulation loops to simplify the controllers. Simulations demonstrate that the strategy adopted allows to obtain a precision better than 0:1% on a 110 kV klystron. Experimental tests have shown that the multiphase converter is able to track a high dynamics reference even under variable output voltage conditions.

  18. Mechanisms of active control for noise inside a vibrating cylinder (United States)

    Lester, Harold C.; Fuller, Chris R.


    The active control of propeller-induced noise fields inside a flexible cylinder is studied with attention given to the noise reduction mechanisms inherent in the present coupled acoustic shell model. The active noise control model consists of an infinitely long aluminum cylinder with a radius of 0.4 m and a thickness of 0.001 m. Pressure maps are shown when the two external sources are driven in-phase at a frequency corresponding to Omega = 0.22.

  19. Controlling neural activity in Caenorhabditis elegans to evoke chemotactic behavior (United States)

    Kocabas, Askin; Shen, Ching-Han; Guo, Zengcai V.; Ramanathan, Sharad


    Animals locate and track chemoattractive gradients in the environment to find food. With its simple nervous system, Caenorhabditis elegans is a good model system in which to understand how the dynamics of neural activity control this search behavior. To understand how the activity in its interneurons coordinate different motor programs to lead the animal to food, here we used optogenetics and new optical tools to manipulate neural activity directly in freely moving animals to evoke chemotactic behavior. By deducing the classes of activity patterns triggered during chemotaxis and exciting individual neurons with these patterns, we identified interneurons that control the essential locomotory programs for this behavior. Notably, we discovered that controlling the dynamics of activity in just one interneuron pair was sufficient to force the animal to locate, turn towards and track virtual light gradients.

  20. Decompression sickness following breath-hold diving. (United States)

    Schipke, J D; Gams, E; Kallweit, Oliver


    Despite convincing evidence of a relationship between breath-hold diving and decompression sickness (DCS), the causal connection is only slowly being accepted. Only the more recent textbooks have acknowledged the risks of repetitive breath-hold diving. We compare four groups of breath-hold divers: (1) Japanese and Korean amas and other divers from the Pacific area, (2) instructors at naval training facilities, (3) spear fishers, and (4) free-dive athletes. While the number of amas is likely decreasing, and Scandinavian Navy training facilities recorded only a few accidents, the number of spear fishers suffering accidents is on the rise, in particular during championships or using scooters. Finally, national and international associations (e.g., International Association of Free Drives [IAFD] or Association Internationale pour Le Developpment De L'Apnee [AIDA]) promote free-diving championships including deep diving categories such as constant weight, variable weight, and no limit. A number of free-diving athletes, training for or participating in competitions, are increasingly accident prone as the world record is presently set at a depth of 171 m. This review presents data found after searching Medline and ISI Web of Science and using appropriate Internet search engines (e.g., Google). We report some 90 cases in which DCS occurred after repetitive breath-hold dives. Even today, the risk of suffering from DCS after repetitive breath-hold diving is often not acknowledged. We strongly suggest that breath-hold divers and their advisors and physicians be made aware of the possibility of DCS and of the appropriate therapeutic measures to be taken when DCS is suspected. Because the risk of suffering from DCS increases depending on depth, bottom time, rate of ascent, and duration of surface intervals, some approaches to assess the risks are presented. Regrettably, none of these approaches is widely accepted. We propose therefore the development of easily manageable

  1. Electrospray ionization of volatiles in breath (United States)

    Martínez-Lozano, P.; de La Mora, J. Fernández


    Recent work by Zenobi and colleagues [H. Chen, A. Wortmann, W. Zhang, R. Zenobi, Angew. Chem. Int. Ed. 46 (2007) 580] reports that human breath charged by contact with an electrospray (ES) cloud yields many mass peaks of species such as urea, glucose, and other ions, some with molecular weights above 1000 Da. All these species are presumed to be involatile, and to originate from breath aerosols by so-called extractive electrospray ionization EESI [H. Chen, A. Venter, R.G. Cooks, Chem. Commun. (2006) 2042]. However, prior work by Fenn and colleagues [C.M. Whitehouse, F. Levin, C.K. Meng, J.B. Fenn, Proceedings of the 34th ASMS Conference on Mass Spectrometry and Allied Topics, Denver, 1986 p. 507; S. Fuerstenau, P. Kiselev, J.B. Fenn, Proceedings of the 47th ASMS Conference on Mass Spectrometry, 1999, Dallas, TX, 1999] and by Hill and colleagues [C. Wu, W.F. Siems, H.H. Hill Jr., Anal. Chem. 72 (2000) 396] have reported the ability of electrospray drops to ionize a variety of low vapor pressure substances directly from the gas phase, without an apparent need for the vapor to be brought into the charging ES in aerosol form. The Ph.D. Thesis of Martínez-Lozano [P. Martínez-Lozano Sinués, Ph.D. Thesis, Department of Thermal and Fluid Engineering, University Carlos III of Madrid; April 5, 2006 (in Spanish);] had also previously argued that the numerous human breath species observed via a similar ES ionization approach were in fact ionized directly from the vapor. Here, we observe that passage of the breath stream through a submicron filter does not eliminate the majority of the breath vapors seen in the absence of the filter. We conclude that direct vapor charging is the leading mechanism in breath ionization by electrospray drops, though aerosol ionization may also play a role.

  2. Active Engine Mounting Control Algorithm Using Neural Network

    Directory of Open Access Journals (Sweden)

    Fadly Jashi Darsivan


    Full Text Available This paper proposes the application of neural network as a controller to isolate engine vibration in an active engine mounting system. It has been shown that the NARMA-L2 neurocontroller has the ability to reject disturbances from a plant. The disturbance is assumed to be both impulse and sinusoidal disturbances that are induced by the engine. The performance of the neural network controller is compared with conventional PD and PID controllers tuned using Ziegler-Nichols. From the result simulated the neural network controller has shown better ability to isolate the engine vibration than the conventional controllers.

  3. Breath testing and personal exposure--SIFT-MS detection of breath acetonitrile for exposure monitoring. (United States)

    Storer, Malina; Curry, Kirsty; Squire, Marie; Kingham, Simon; Epton, Michael


    Breath testing has potential for the rapid assessment of the source and impact of exposure to air pollutants. During the development of a breath test for acetonitrile using selected ion flow tube mass spectrometry (SIFT-MS) raised acetonitrile concentrations in the breath of volunteers were observed that could not be explained by known sources of exposure. Workplace/laboratory exposure to acetonitrile was proposed since this was common to the volunteers with increased breath concentrations. SIFT-MS measurements of acetonitrile in breath and air were used to confirm that an academic chemistry laboratory was the source of exposure to acetonitrile, and quantify the changes that occurred to exhaled acetonitrile after exposure. High concentrations of acetonitrile were detected in the air of the chemistry laboratory. However, concentrations in the offices were not significantly different across the campus. There was a significant difference in the exhaled acetonitrile concentrations of people who worked in the chemistry laboratories (exposed) and those who did not (non-exposed). SIFT-MS testing of air and breath made it possible to determine that occupational exposure to acetonitrile in the chemistry laboratory was the cause of increased exhaled acetonitrile. Additionally, the sensitivity was adequate to measure the changes to exhaled amounts and found that breath concentrations increased quickly with short exposure and remained increased even after periods of non-exposure. There is potential to add acetonitrile to a suite of VOCs to investigate source and impact of poor air quality.

  4. Medication effects on sleep and breathing. (United States)

    Seda, Gilbert; Tsai, Sheila; Lee-Chiong, Teofilo


    Sleep respiration is regulated by circadian, endocrine, mechanical and chemical factors, and characterized by diminished ventilatory drive and changes in Pao2 and Paco2 thresholds. Hypoxemia and hypercapnia are more pronounced during rapid eye movement. Breathing is influenced by sleep stage and airway muscle tone. Patient factors include medical comorbidities and body habitus. Medications partially improve obstructive sleep apnea and stabilize periodic breathing at altitude. Potential adverse consequences of medications include precipitation or worsening of disorders. Risk factors for adverse medication effects include aging, medical disorders, and use of multiple medications that affect respiration.

  5. Modeling and Control of Active Suspensions for MDOF Vehicle

    Institute of Scientific and Technical Information of China (English)

    李克强; 郑四发; 杨殿阁; 连小珉; 永井正夫


    The conventional method for analyzing active suspension control for a vehicle is only to analyze aquarter or half car with a lower order degree-of freedom (DOF) model, but such models do not actually modelpractical applications. Accurate models of a suspension control system require a multi-degree-of-freedom(MDOF) vehicle model with a detailed model of the controller. An MDOF model was developed including theinfluence of factors such as the engine, the seats, and the passengers to describe vehicle motion using areduced order model of the controller designed by using the H∞ control method. The control systemperformance has been investigated by comparing the H∞ controller with a linear quadratic (LQ) controller.

  6. Feedforward control of sound transmission using an active acoustic metamaterial (United States)

    Cheer, Jordan; Daley, Stephen; McCormick, Cameron


    Metamaterials have received significant interest in recent years due to their potential ability to exhibit behaviour not found in naturally occurring materials. This includes the generation of band gaps, which are frequency regions with high levels of wave attenuation. In the context of acoustics, these band gaps can be tuned to occur at low frequencies where the acoustic wavelength is large compared to the material, and where the performance of traditional passive noise control treatments is limited. Therefore, such acoustic metamaterials have been shown to offer a significant performance advantage compared to traditional passive control treatments, however, due to their resonant behaviour, the band gaps tend to occur over a relatively narrow frequency range. A similar long wavelength performance advantage can be achieved using active noise control, but the systems in this case do not rely on resonant behaviour. This paper demonstrates how the performance of an acoustic metamaterial, consisting of an array of Helmholtz resonators, can be significantly enhanced by the integration of an active control mechanism that is facilitated by embedding loudspeakers into the resonators. Crucially, it is then also shown how the active acoustic metamaterial significantly outperforms an equivalent traditional active noise control system. In both cases a broadband feedforward control strategy is employed to minimise the transmitted pressure in a one-dimensional acoustic control problem and a new method of weighting the control effort over a targeted frequency range is described.

  7. Smart Materials and Active Noise and Vibration Control in Vehicles

    NARCIS (Netherlands)

    Doppenberg, E.J.J.; Berkhoff, A.P.; Overbeek, van M.


    The paper presents the results for the reduction of sound radiated from a structure using different control methodologies, and discusses two approaches for active structural acoustic control: the acoustic approach or the vibro-acoustic approach. Integrated actuators in structure material are necessa

  8. Applications of active adaptive noise control to jet engines (United States)

    Shoureshi, Rahmat; Brackney, Larry


    During phase 2 research on the application of active noise control to jet engines, the development of multiple-input/multiple-output (MIMO) active adaptive noise control algorithms and acoustic/controls models for turbofan engines were considered. Specific goals for this research phase included: (1) implementation of a MIMO adaptive minimum variance active noise controller; and (2) turbofan engine model development. A minimum variance control law for adaptive active noise control has been developed, simulated, and implemented for single-input/single-output (SISO) systems. Since acoustic systems tend to be distributed, multiple sensors, and actuators are more appropriate. As such, the SISO minimum variance controller was extended to the MIMO case. Simulation and experimental results are presented. A state-space model of a simplified gas turbine engine is developed using the bond graph technique. The model retains important system behavior, yet is of low enough order to be useful for controller design. Expansion of the model to include multiple stages and spools is also discussed.

  9. Active and passive control of zinc phthalocyanine photodynamics

    NARCIS (Netherlands)

    Sharma, D.; Huijser, J.M.; Savolainen, J.; Steen, G.W.; Herek, J.L.


    In this work we report on the ultrafast photodynamics of the photosensitizer zinc phthalocyanine (ZnPc) and manipulation thereof. Two approaches are followed: active control via pulse shaping and passive control via strategic manipulation in the periphery of the molecular structure. The objective of

  10. Finite element models applied in active structural acoustic control

    NARCIS (Netherlands)

    Oude Nijhuis, Marco H.H.; Boer, de André; Rao, Vittal S.


    This paper discusses the modeling of systems for active structural acoustic control. The finite element method is applied to model structures including the dynamics of piezoelectric sensors and actuators. A model reduction technique is presented to make the finite element model suitable for controll

  11. Combined Active and Reactive Power Control of Wind Farms based on Model Predictive Control

    DEFF Research Database (Denmark)

    Zhao, Haoran; Wu, Qiuwei; Wang, Jianhui;


    This paper proposes a combined wind farm controller based on Model Predictive Control (MPC). Compared with the conventional decoupled active and reactive power control, the proposed control scheme considers the significant impact of active power on voltage variations due to the low X=R ratio...... of wind farm collector systems. The voltage control is improved. Besides, by coordination of active and reactive power, the Var capacity is optimized to prevent potential failures due to Var shortage, especially when the wind farm operates close to its full load. An analytical method is used to calculate...... the sensitivity coefficients to improve the computation efficiency and overcome the convergence problem. Two control modes are designed for both normal and emergency conditions. A wind farm with 20 wind turbines was used to verify the proposed combined control scheme....

  12. O impacto do tratamento fonoaudiológico no controle da asma e da rinite alérgica em crianças e adolescentes respiradores orais The impact of speech therapy on asthma and allergic rhinitis control in mouth breathing children and adolescents

    Directory of Open Access Journals (Sweden)

    Silvia M. A. Campanha


    Full Text Available OBJETIVO: Detectar o impacto do tratamento fonoaudiológico no controle da asma e da rinite alérgica em crianças e adolescentes respiradores orais. MÉTODOS: Trata-se de um estudo quase-experimental; foram randomizados 24 pacientes com asma, rinite alérgica e respiração oral, idade de 6 a 15 anos. Todos os pacientes usavam dipropionato beclometasona inalação oral. No momento em que aceitaram participar da pesquisa, a inalação oral foi substituída pela inalação exclusivamente nasal na inspiração e, após 1 mês, associou-se ao tratamento fonoaudiológico em metade dos pacientes. Esses receberam 16 sessões de tratamento fonoaudiológico em 8 semanas, além do dipropionato de beclometasona inalação exclusivamente nasal (grupo DBF. O grupo de comparação recebeu somente dipropionato beclometasona inalação exclusivamente nasal (grupo DBI. Os dois grupos foram avaliados em cinco tempos. Utilizou-se o escore clínico da rinite alérgica, da asma, o protocolo de avaliação miofuncional orofacial adaptado de Marchesan (2003, a observação dos responsáveis, dados de espirometria, de pico de fluxo inspiratório e de pico de fluxo expiratório. RESULTADOS: Houve melhora significativa do grupo DBF: escores clínicos da asma no tempo 5 (p = 0,046; valores do pico de fluxo inspiratório no tempo 4 (p = 0,030; pico de fluxo expiratório no tempo 3 (p = 0,008; modo respiratório e postura de lábios (p = 0,000 a partir do tempo 3; observação dos responsáveis, no tempo 2, tempo 4 e tempo 5 (p = 0,010; p = 0,027; p = 0,030. CONCLUSÕES: O tratamento fonoaudiológico associado ao dipropionato beclometasona por inalação exclusivamente nasal promoveu um controle clínico e funcional mais precoce e duradouro da asma, da rinite alérgica e da respiração oral entre os grupos estudados.OBJECTIVE: To determine the impact of speech therapy on asthma and allergic rhinitis control in mouth breathing children and adolescents. METHODS: This was a

  13. Breath figures of two immiscible substances on a repellent surface (United States)

    Guadarrama-Cetina, J.; González-Viñas, W.


    The understanding of the competition between different substances while condensing on a cold surface is of high interest in situations in which it is desirable to control their condensation rates and the formed morphologies. We do the experiments for mixtures of water and hexamethyldisiloxane vapors at several concentrations. The dropwise condensation of the vapors forms breath figures on a substrate that is repellant to both substances. We report the average radius of the drops for each specie as a function of time. Also, we pay attention to the evolution of the corresponding morphologies and the appearance of hybrid clusters.

  14. Active Disturbance Rejection Approach for Robust Fault-Tolerant Control via Observer Assisted Sliding Mode Control


    John Cortés-Romero; Harvey Rojas-Cubides; Horacio Coral-Enriquez; Hebertt Sira-Ramírez; Alberto Luviano-Juárez


    This work proposes an active disturbance rejection approach for the establishment of a sliding mode control strategy in fault-tolerant operations. The core of the proposed active disturbance rejection assistance is a Generalized Proportional Integral (GPI) observer which is in charge of the active estimation of lumped nonlinear endogenous and exogenous disturbance inputs related to the creation of local sliding regimes with limited control authority. Possibilities are explored for the GPI obs...

  15. A new approach of active compliance control via fuzzy logic control for multifingered robot hand (United States)

    Jamil, M. F. A.; Jalani, J.; Ahmad, A.


    Safety is a vital issue in Human-Robot Interaction (HRI). In order to guarantee safety in HRI, a model reference impedance control can be a very useful approach introducing a compliant control. In particular, this paper establishes a fuzzy logic compliance control (i.e. active compliance control) to reduce impact and forces during physical interaction between humans/objects and robots. Exploiting a virtual mass-spring-damper system allows us to determine a desired compliant level by understanding the behavior of the model reference impedance control. The performance of fuzzy logic compliant control is tested in simulation for a robotic hand known as the RED Hand. The results show that the fuzzy logic is a feasible control approach, particularly to control position and to provide compliant control. In addition, the fuzzy logic control allows us to simplify the controller design process (i.e. avoid complex computation) when dealing with nonlinearities and uncertainties.

  16. Composition for the controlled release of active compounds

    NARCIS (Netherlands)

    Hovens, I.A.P.; Jongboom, R.O.J.; Stuut, P.I.


    The invention provides a composition for the controlled release of one or more biologically active substances encapsulated in a degradable biopolymer matrix, consisting of a thermoplastic and/or partly crystalline inulin. A plasticiser such as glycerol, and an emulsifier may be present. The active s

  17. Breathing adapted radiotherapy for breast cancer: comparison of free breathing gating with the breath-hold technique

    DEFF Research Database (Denmark)

    Korreman, Stine Sofia; Pedersen, Anders N; Nøttrup, Trine Jakobi;


    -hold (EBH). The Varian Real-time Position Management system (RPM) was used to monitor respiratory movement and to gate the scanner. For each breathing phase, a population based internal margin (IM) was estimated based on average chest wall excursion, and incorporated into an individually optimised three...

  18. Improving active space telescope wavefront control using predictive thermal modeling (United States)

    Gersh-Range, Jessica; Perrin, Marshall D.


    Active control algorithms for space telescopes are less mature than those for large ground telescopes due to differences in the wavefront control problems. Active wavefront control for space telescopes at L2, such as the James Webb Space Telescope (JWST), requires weighing control costs against the benefits of correcting wavefront perturbations that are a predictable byproduct of the observing schedule, which is known and determined in advance. To improve the control algorithms for these telescopes, we have developed a model that calculates the temperature and wavefront evolution during a hypothetical mission, assuming the dominant wavefront perturbations are due to changes in the spacecraft attitude with respect to the sun. Using this model, we show that the wavefront can be controlled passively by introducing scheduling constraints that limit the allowable attitudes for an observation based on the observation duration and the mean telescope temperature. We also describe the implementation of a predictive controller designed to prevent the wavefront error (WFE) from exceeding a desired threshold. This controller outperforms simpler algorithms even with substantial model error, achieving a lower WFE without requiring significantly more corrections. Consequently, predictive wavefront control based on known spacecraft attitude plans is a promising approach for JWST and other future active space observatories.

  19. In vivo proton MRS of normal pancreas metabolites during breath-holding and free-breathing

    Energy Technology Data Exchange (ETDEWEB)

    Su, T.-H. [Department of Radiology, Beijing Friendship Hospital, Capital Medical University, 95 Yong-An Road, Beijing (China); Jin, E.-H., E-mail: [Department of Radiology, Beijing Friendship Hospital, Capital Medical University, 95 Yong-An Road, Beijing (China); Shen, H. [GE China Company Ltd, Healthcare, General Electric Company, Beijing (China); Zhang, Y.; He, W. [Department of Radiology, Beijing Friendship Hospital, Capital Medical University, 95 Yong-An Road, Beijing (China)


    Aim: To characterize normal pancreas metabolites using in vivo proton magnetic resonance spectroscopy ({sup 1}H MRS) at 3 T under conditions of breath-holding and free-breathing. Materials and methods: The pancreases of 32 healthy volunteers were examined using {sup 1}H MRS during breath-holding and free-breathing acquisitions in a single-voxel point-resolved selective spectroscopy sequence (PRESS) technique using a 3 T MRI system. Resonances were compared between paired spectra of the two breathing modes. Furthermore, correlations between lipid (Lip) content and age, body-mass index (BMI), as well as choline (Cho) peak visibility of the normal pancreas were analysed during breath-holding. Results: Twenty-nine pairs of spectra were successfully obtained showing three major resonances, Lip, Cho, cholesterol and the unsaturated parts of the olefinic region of fatty acids (Chol + Unsat). Breath-hold spectra were generally better, with higher signal-to-noise ratios (SNR; Z=-2.646, p = 0.008) and Cho peak visible status (Z=-2.449, p = 0.014). Correlations were significant between spectra acquired by the two breathing modes, especially for Lip height, Lip area, and the area of other peaks at 1.9-4.1 ppm. However, the Lip resonance was significantly different between the spectra of the two breathing modes (p < 0.05). In the breath-holding spectra, there were significant positive correlations between Lip peak height, area, and age (r = 0.491 and 0.521, p = 0.007 and 0.004), but not between Lip peak area and BMI. There was no statistical difference in Cho resonances between males and females. The Lip peak height and area were significantly higher in the Cho peak invisible group than in the Cho peak visible group (t = 2.661 and 2.353, p = 0.030 and 0.043). Conclusion: In vivo{sup 1}H MRS of the normal pancreas at 3 T is technically feasible and can characterize several metabolites. {sup 1}H MRS during breath-holding acquisition is superior to that during free-breathing

  20. Radial Breathing Modes in Cosmochemistry and Meteoritics (United States)

    Wilson, T.L.; Wilson, K.B.


    One area of continuing interest in cosmochemistry and meteoritics (C&M) is the identification of the nature of Q-phase, although some researchers in C&M are not reporting relevant portions of Raman spectral data. Q is the unidentified carrier of noble gases in carbonaceous chondrites (CCs). Being carbonaceous, the focus has been on any number of Q-candidates arising from the sp2 hybridization of carbon (C). These all derive from various forms of graphene, a monolayer of C atoms packed into a two-dimensional (2D) hexagonal honeycomb lattice that is the basic building block for graphitic materials of all other dimensions for sp2 allotropes of C. As a basic lattice, 2D graphene can be curled into fullerenes (0D), wrapped into carbon nanotubes or CNTs (1D), and stacked into graphite (3D). These take such additional forms as scroll-like carbon whiskers, carbon fibers, carbon onions, GPCs (graphite polyhedral crystals) [6], and GICs (graphite intercalation compounds). Although all of these have been observed in meteoritics, the issue is which can explain the Q-abundances. In brief, one or more of the 0D-3D sp2 hybridization forms of C is Q. For some Q-candidates, the radial breathing modes (RBMs) are the most important Raman active vibrational modes that exist, and bear a direct relevance to solving this puzzle. Typically in C&M they are ignored when present. Their importance is addressed here as smoking-gun signatures for certain Q-candidates and are very relevant to the ultimate identification of Q.

  1. Impact of active controls technology on structural integrity (United States)

    Noll, Thomas; Austin, Edward; Donley, Shawn; Graham, George; Harris, Terry


    This paper summarizes the findings of The Technical Cooperation Program to assess the impact of active controls technology on the structural integrity of aeronautical vehicles and to evaluate the present state-of-the-art for predicting the loads caused by a flight-control system modification and the resulting change in the fatigue life of the flight vehicle. The potential for active controls to adversely affect structural integrity is described, and load predictions obtained using two state-of-the-art analytical methods are given.

  2. UML activity diagram swimlanes in logic controller design (United States)

    Grobelny, Michał; Grobelna, Iwona


    Logic controller behavior can be specified using various techniques, including UML activity diagrams and control Petri nets. Each technique has its advantages and disadvantages. Application of both specification types in one project allows to take benefits from both of them. Additional elements of UML models make it possible to divide a specification into some parts, considered from other point of view (logic controller, user or system). The paper introduces an idea to use UML activity diagrams with swimlanes to increase the understandability of design models.

  3. Remote Control of T Cell Activation Using Magnetic Janus Particles. (United States)

    Lee, Kwahun; Yi, Yi; Yu, Yan


    We report a strategy for using magnetic Janus microparticles to control the stimulation of T cell signaling with single-cell precision. To achieve this, we designed Janus particles that are magnetically responsive on one hemisphere and stimulatory to T cells on the other side. By manipulating the rotation and locomotion of Janus particles under an external magnetic field, we could control the orientation of the particle-cell recognition and thereby the initiation of T cell activation. This study demonstrates a step towards employing anisotropic material properties of Janus particles to control single-cell activities without the need of complex magnetic manipulation devices.

  4. Active member bridge feedback control for damping augmentation (United States)

    Chen, Gun-Shing; Lurie, Boris J.


    An active damping augmentation approach using active members in a structural system is described. The problem of maximizing the vibration damping in a lightly damped structural system is considered using the analogy of impedance matching between the load and source impedances in an electrical network. The proposed active damping augmentation approach therefore consists of finding the desired active member impedances that maximize the vibration damping, and designing a feedback control in order to achieve desired active member impedances. This study uses a bridge feedback concept that feeds back a combination of signals from sensors of the axial force and relative velocity across the active member to realize the desired active member impedance. The proposed active damping augmentation approach and bridge feedback concept were demonstrated on a three-longeron softly suspended truss structure.

  5. Robust Vehicle Suspension System by Converting Active & Passive Control of a Vehicle to Semi-Active Control System Analytically

    Directory of Open Access Journals (Sweden)

    Hassan Elahi


    Full Text Available In this research work a simplified translational model of an automotive suspension system is constructed by only considering the translation motion of one wheel of a car. Passive Vehicle Suspension System is converted into Semi Active Vehicle System. Major advantage achieved by this system is that it adjusts the damping of the suspension system without the application of any actuator by using MATLAB® simulations. The semi-active control is found to control the vibration of suspension system very well.

  6. A mind you can count on: validating breath counting as a behavioral measure of mindfulness

    Directory of Open Access Journals (Sweden)

    Daniel B Levinson


    Full Text Available Mindfulness practice of present moment awareness promises many benefits, but has eluded rigorous behavioral measurement. To date, research has relied on self-reported mindfulness or heterogeneous mindfulness trainings to infer skillful mindfulness practice and its effects. In four independent studies with over 400 total participants, we present the first construct validation of a behavioral measure of mindfulness, breath counting. We found it was reliable, correlated with self-reported mindfulness, differentiated long-term meditators from age-matched controls, and was distinct from sustained attention and working memory measures. In addition, we employed breath counting to test the nomological network of mindfulness. As theorized, we found skill in breath counting associated with more meta-awareness, less mind wandering, better mood, and greater nonattachment (i.e. less attentional capture by distractors formerly paired with reward. We also found in a randomized online training study that 4 weeks of breath counting training improved mindfulness and decreased mind wandering relative to working memory training and no training controls. Together, these findings provide the first evidence for breath counting as a behavioral measure of mindfulness.

  7. Systematic review of the effectiveness of breathing retraining in asthma management. (United States)

    Burgess, John; Ekanayake, Buddhini; Lowe, Adrian; Dunt, David; Thien, Francis; Dharmage, Shyamali C


    In asthma management, complementary and alternative medicine is enjoying a growing popularity worldwide. This review synthesizes the literature on complementary and alternative medicine techniques that utilize breathing retraining as their primary component and compares evidence from controlled trials with before-and-after trials. Medline, PubMed, Cumulative Index to Nursing and Allied Health Literature and the Cochrane Library electronic databases were searched. Reference lists of all publications were manually checked to identify studies not found through electronic searching. The selection criteria were met by 41 articles. Most randomized controlled trials (RCTs) of the Buteyko breathing technique demonstrated a significant decrease in β(2)-agonist use while several found improvement in quality of life or decrease in inhaled corticosteroid use. Although few in number, RCTs of respiratory muscle training found a significant reduction in bronchodilator medication use. Where meta-analyses could be done, they provided evidence of benefit from yoga, Buteyko breathing technique and physiotherapist-led breathing training in improving asthma-related quality of life. However, considerable heterogeneity was noted in some RCTs of yoga. It is reasonable for clinicians to offer qualified support to patients with asthma undertaking these breathing retraining techniques.

  8. Neural Network-Based Active Control for Offshore Platforms

    Institute of Scientific and Technical Information of China (English)

    周亚军; 赵德有


    A new active control scheme, based on neural network, for the suppression of oscillation in multiple-degree-of-freedom (MDOF) offshore platforms, is studied in this paper. With the main advantages of neural network, i.e. the inherent robustness, fault tolerance, and generalized capability of its parallel massive interconnection structure, the active structural control of offshore platforms under random waves is accomplished by use of the BP neural network model. The neural network is trained offline with the data generated from numerical analysis, and it simulates the process of Classical Linear Quadratic Regular Control for the platform under random waves. After the learning phase, the trained network has learned about the nonlinear dynamic behavior of the active control system, and is capable of predicting the active control forces of the next time steps. The results obtained show that the active control is feasible and effective, and it finally overcomes time delay owing to the robustness, fault tolerance, and generalized capability of artificial neural network.

  9. Active inference and robot control: a case study. (United States)

    Pio-Lopez, Léo; Nizard, Ange; Friston, Karl; Pezzulo, Giovanni


    Active inference is a general framework for perception and action that is gaining prominence in computational and systems neuroscience but is less known outside these fields. Here, we discuss a proof-of-principle implementation of the active inference scheme for the control or the 7-DoF arm of a (simulated) PR2 robot. By manipulating visual and proprioceptive noise levels, we show under which conditions robot control under the active inference scheme is accurate. Besides accurate control, our analysis of the internal system dynamics (e.g. the dynamics of the hidden states that are inferred during the inference) sheds light on key aspects of the framework such as the quintessentially multimodal nature of control and the differential roles of proprioception and vision. In the discussion, we consider the potential importance of being able to implement active inference in robots. In particular, we briefly review the opportunities for modelling psychophysiological phenomena such as sensory attenuation and related failures of gain control, of the sort seen in Parkinson's disease. We also consider the fundamental difference between active inference and optimal control formulations, showing that in the former the heavy lifting shifts from solving a dynamical inverse problem to creating deep forward or generative models with dynamics, whose attracting sets prescribe desired behaviours.

  10. Active inference and robot control: a case study (United States)

    Nizard, Ange; Friston, Karl; Pezzulo, Giovanni


    Active inference is a general framework for perception and action that is gaining prominence in computational and systems neuroscience but is less known outside these fields. Here, we discuss a proof-of-principle implementation of the active inference scheme for the control or the 7-DoF arm of a (simulated) PR2 robot. By manipulating visual and proprioceptive noise levels, we show under which conditions robot control under the active inference scheme is accurate. Besides accurate control, our analysis of the internal system dynamics (e.g. the dynamics of the hidden states that are inferred during the inference) sheds light on key aspects of the framework such as the quintessentially multimodal nature of control and the differential roles of proprioception and vision. In the discussion, we consider the potential importance of being able to implement active inference in robots. In particular, we briefly review the opportunities for modelling psychophysiological phenomena such as sensory attenuation and related failures of gain control, of the sort seen in Parkinson's disease. We also consider the fundamental difference between active inference and optimal control formulations, showing that in the former the heavy lifting shifts from solving a dynamical inverse problem to creating deep forward or generative models with dynamics, whose attracting sets prescribe desired behaviours. PMID:27683002

  11. Active structural control by fuzzy logic rules: An introduction

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Yu [Argonne National Lab., IL (United States). Reactor Engineering Div.; Wu, Kung C. [Texas Univ., El Paso, TX (United States). Dept. of Mechanical and Industrial Engineering


    A zeroth level introduction to fuzzy logic control applied to the active structural control to reduce the dynamic response of structures subjected to earthquake excitations is presented. It is hoped that this presentation will increase the attractiveness of the methodology to structural engineers in research as well as in practice. The basic concept of the fuzzy logic control are explained by examples and by diagrams with a minimum of mathematics. The effectiveness and simplicity of the fuzzy logic control is demonstrated by a numerical example in which the response of a single- degree-of-freedom system subjected to earthquake excitations is controlled by making use of the fuzzy logic controller. In the example, the fuzzy rules are first learned from the results obtained from linear control theory; then they are fine tuned to improve their performance. It is shown that the performance of fuzzy logic control surpasses that of the linear control theory. The paper shows that linear control theory provides experience for fuzzy logic control, and fuzzy logic control can provide better performance; therefore, two controllers complement each other.

  12. Developing active noise control systems for noise attenuation in ducts (United States)

    Campos, Rosely V.; Ivo, Rodrigo C.; Medeiros, Eduardo B.


    The present work describes some of the research effort on Active Noise Control (ANC) being jointly developed by the Catholic University of Minas Gerais (PUC-MINAS) and the Federal University of Minas Gerais (UFMG). Considerations about the implementation of Digital Signal Processing for noise control in ducts has been presented. The objective is to establish a study on Active Noise Control in ducts combining geometry and acoustic parameters modification together with adaptive digital filtering implementation. Both algorithm and digital signal processing details are also discussed. The main results for a typical application where real attenuation has been obtained are presented and considered according to their use in developing real applications. The authors also believe that the present text should provide an interesting overview for both designers and students concerned about Active Noise Control in ducts. (To be presented in Portuguese.)

  13. Active disturbance rejection control for fractional-order system. (United States)

    Li, Mingda; Li, Donghai; Wang, Jing; Zhao, Chunzhe


    Fractional-order proportional-integral (PI) and proportional-integral-derivative (PID) controllers are the most commonly used controllers in fractional-order systems. However, this paper proposes a simple integer-order control scheme for fractional-order system based on active disturbance rejection method. By treating the fractional-order dynamics as a common disturbance and actively rejecting it, active disturbance rejection control (ADRC) can achieve the desired response. External disturbance, sensor noise, and parameter disturbance are also estimated using extended state observer. The ADRC stability of rational-order model is analyzed. Simulation results on three typical fractional-order systems are provided to demonstrate the effectiveness of the proposed method.

  14. 42 CFR 84.195 - Breathing tubes; minimum requirements. (United States)


    ... Cartridge Respirators § 84.195 Breathing tubes; minimum requirements. Flexible breathing tubes used in conjunction with respirators shall be designed and constructed to prevent: (a) Restriction of free...

  15. 42 CFR 84.132 - Breathing tubes; minimum requirements. (United States)


    ... Respirators § 84.132 Breathing tubes; minimum requirements. Flexible breathing tubes used in conjunction with supplied-air respirators shall be designed and constructed to prevent: (a) Restriction of free...

  16. Apolo Ohno: Breathing Easier | NIH MedlinePlus the Magazine (United States)

    ... please turn Javascript on. Feature: Breathing Easier Apolo Ohno: Breathing Easier Past Issues / Fall 2013 Table of ... skating. What does the future hold for Apolo Ohno? Even though I'm no longer skating competitively, ...

  17. "Active Flux" DTFC-SVM Sensorless Control of IPMSM

    DEFF Research Database (Denmark)

    Boldea, Ion; Codruta Paicu, Mihaela; Gheorghe-Daniel, Andreescu,


    . The concept of "active flux" (or "torque producing flux") turns all the rotor salient-pole ac machines into fully nonsalient-pole ones. A new function for Lq inductance depending on torque is introduced to model the magnetic saturation. Notable simplification in the rotor position and speed estimation...... is obtained, because the active flux position is identical with the rotor position. Extensive experimental results are presented to verify the principles and to demonstrate the effectiveness of the proposed sensorless control system. With the active flux observer, the IPMSM drive system operates from very low......This paper proposes an implementation of a motionsensorless control system in wide speed range based on "active flux" observer, and direct torque and flux control with space vector modulation (DTFC-SVM) for the interior permanent magnet synchronous motor (IPMSM), without signal injection...

  18. Active vibration control using state space LQG and internal model control methods

    DEFF Research Database (Denmark)

    Mørkholt, Jakob; Elliott, S.J.


    Two ways of designing discrete time robust H2-controllers for feedback broadband active vibration control are compared through computer simulations. The methods are based on different models of disturbance and plant transfer functions, but yield controllers with identical properties. Two simple...... ways of introducing robustness into the H2-design are compared, and finally an efficient way of designing a practical IIR-controller is proposed....

  19. Role of cerebral blood flow in extreme breath holding

    Directory of Open Access Journals (Sweden)

    Bain Anthony R.


    Full Text Available The role of cerebral blood flow (CBF on a maximal breath-hold (BH in ultra-elite divers was examined. Divers (n = 7 performed one control BH, and one BH following oral administration of the non-selective cyclooxygenase inhibitor indomethacin (1.2 mg/kg. Arterial blood gases and CBF were measured prior to (baseline, and at BH termination. Compared to control, indomethacin reduced baseline CBF and cerebral delivery of oxygen (CDO2 by about 26% (p < 0.01. Indomethacin reduced maximal BH time from 339 ± 51 to 319 ± 57 seconds (p = 0.04. In both conditions, the CDO2 remained unchanged from baseline to the termination of apnea. At BH termination, arterial oxygen tension was higher following oral administration of indomethacin compared to control (4.05 ± 0.45 vs. 3.44 ± 0.32 kPa. The absolute increase in CBF from baseline to the termination of apnea was lower with indomethacin (p = 0.01. These findings indicate that the impact of CBF on maximal BH time is likely attributable to its influence on cerebral H+ washout, and therefore central chemoreceptive drive to breathe, rather than to CDO2.

  20. Active structural vibration control: Robust to temperature variations (United States)

    Gupta, Vivek; Sharma, Manu; Thakur, Nagesh


    d-form augmented piezoelectric constitutive equations which take into account temperature dependence of piezoelectric strain coefficient (d31) and permittivity (∈33), are converted into e-form. Using e-form constitutive equations, a finite element model of a smart two dimensional plate instrumented with piezoelectric patches is derived. Equations of motion are derived using Hamilton's variational principle. Coupled equations of motion are uncoupled using modal analysis. Modal state vectors are estimated using the Kalman observer. The first mode of smart cantilevered plate is actively controlled using negative first modal velocity feedback at various temperatures. Total control effort required to do so is calculated using the electro-mechanical impedance method. The temperature dependence of sensor voltage, control voltage, control effort and Kalman observer equations is shown analytically. Simulation results are presented using MATLAB. Variations in (i) peak sensor voltage, (ii) actual and estimated first modal velocities, (iii) peak control voltage, (iv) total control effort and (v) settling time with respect to temperature are presented. Active vibration control performance is not maintained at temperature away from reference temperature when the temperature dependence of piezoelectric stress coefficient ‘e31' and permittivity ‘∈33' is not included in piezoelectric constitutive equations. Active control of vibrations becomes robust to temperature variations when the temperature dependence of ‘e31' and ‘∈33' is included in piezoelectric constitutive equations.

  1. Measuring breath acetone for monitoring fat loss: Review


    Anderson, Joseph C.


    Objective Endogenous acetone production is a by‐product of the fat metabolism process. Because of its small size, acetone appears in exhaled breath. Historically, endogenous acetone has been measured in exhaled breath to monitor ketosis in healthy and diabetic subjects. Recently, breath acetone concentration (BrAce) has been shown to correlate with the rate of fat loss in healthy individuals. In this review, the measurement of breath acetone in healthy subjects is evaluated for its utility in...

  2. The application of active noise control technology to reduce noise from air pollution control equipment

    Energy Technology Data Exchange (ETDEWEB)

    Depies, C. R.; Kapsos, D. W.


    The basic concept of active noise control, i. e. to create a noise field in a space in order to destructively interfere with an existing noise, and in the process create a quieter space, was explained. The manner in which noise control technology can be used in air pollution control equipment was described and guidelines for application were provided. A number of case studies were used to illustrate the suitability of active noise control for low frequency noise problems, especially in the area of air pollution control equipment. Impressive reduction of low frequency noise, energy efficiency, ability to retrofit into an existing duct system, and the hardware`s insensitivity to dirty exhaust environments were cited as the principal reasons for the success of active noise control technology over more traditional in-line passive silencers. 1 ref., 8 figs.

  3. The effects of physical activity on functional MRI activation associated with cognitive control in children: a randomized controlled intervention

    Directory of Open Access Journals (Sweden)

    Laura eChaddock-Heyman


    Full Text Available This study used functional magnetic resonance imaging (fMRI to examine the influence of a 9-month physical activity program on task-evoked brain activation during childhood. The results demonstrated that 8- to 9-year-old children who participated in 60+ minutes of physical activity, 5 days per week, for 9 months, showed decreases in fMRI brain activation in the right anterior prefrontal cortex coupled with within-group improvements in performance on a task of attentional and interference control. Children assigned to a wait list control group did not show changes in brain function. Furthermore, at post-test, children in the physical activity group showed similar anterior frontal brain patterns and incongruent accuracy rates to a group of college-aged young adults. Children in the wait list control group still differed from the young adults in terms of anterior prefrontal activation and performance at post-test. There were no significant changes in fMRI activation in the anterior cingulate cortex for either group. These results suggest that physical activity during childhood may enhance specific elements of prefrontal cortex function involved in cognitive control.

  4. Passive, Active and Semi-Active Control Systems in Civil Engineering

    Directory of Open Access Journals (Sweden)

    Septimiu-George Luca


    Full Text Available In the recent years many techniques has been developed to reduce the vibration response in civil structure, such as tall buildings and long bridges. Attention of this paper is focused on the difference among passive, active and semi-active control systems. If passive control systems are used enhancing structural damping, stiffness or strength, the other control techniques employ controllable forces to add or dissipate, or both, energy in a structure due to the specific devices integrated with sensors, controllers and real-time processes to operating. Some applications will be proposed and applied to single degree of freedom systems in vertical working conditions.

  5. Elevated carbon monoxide in the exhaled breath of mice during a systemic bacterial infection.

    Directory of Open Access Journals (Sweden)

    Alan G Barbour

    Full Text Available Blood is the specimen of choice for most laboratory tests for diagnosis and disease monitoring. Sampling exhaled breath is a noninvasive alternative to phlebotomy and has the potential for real-time monitoring at the bedside. Improved instrumentation has advanced breath analysis for several gaseous compounds from humans. However, application to small animal models of diseases and physiology has been limited. To extend breath analysis to mice, we crafted a means for collecting nose-only breath samples from groups and individual animals who were awake. Samples were subjected to gas chromatography and mass spectrometry procedures developed for highly sensitive analysis of trace volatile organic compounds (VOCs in the atmosphere. We evaluated the system with experimental systemic infections of severe combined immunodeficiency Mus musculus with the bacterium Borrelia hermsii. Infected mice developed bacterial densities of ∼10(7 per ml of blood by day 4 or 5 and in comparison to uninfected controls had hepatosplenomegaly and elevations of both inflammatory and anti-inflammatory cytokines. While 12 samples from individual infected mice on days 4 and 5 and 6 samples from uninfected mice did not significantly differ for 72 different VOCs, carbon monoxide (CO was elevated in samples from infected mice, with a mean (95% confidence limits effect size of 4.2 (2.8-5.6, when differences in CO2 in the breath were taken into account. Normalized CO values declined to the uninfected range after one day of treatment with the antibiotic ceftriaxone. Strongly correlated with CO in the breath were levels of heme oxygenase-1 protein in serum and HMOX1 transcripts in whole blood. These results (i provide further evidence of the informativeness of CO concentration in the exhaled breath during systemic infection and inflammation, and (ii encourage evaluation of this noninvasive analytic approach in other various other rodent models of infection and for utility in

  6. Breathing Better with a COPD Diagnosis (United States)

    Now that you kNow it’s CoPD, here’s how to breathe better. You have taken the important step of being aware of your symptoms, and seeing your doctor ... care provider for testing and a diagnosis. While COPD (Chronic Obstructive Pulmonary Disease) is a serious lung ...

  7. Ineffective breathing pattern related to malnutrition. (United States)

    Openbrier, D R; Covey, M


    This article has highlighted the problem of malnutrition in the stable COPD patient and the critically ill, hypercatabolic patient, and has reviewed resultant mechanisms which influence the alteration of breathing pattern. These complex patients present a challenge for the nurse. Table 1 briefly summarizes the manifestations of malnutrition, goals, interventions and expected outcomes of the nursing diagnosis, ineffective breathing pattern related to malnutrition. The goal of the interventions is to modify the cause (malnutrition) of the nursing diagnosis (altered breathing pattern). The success of the interventions will lead to the achievement of expected outcome As expected outcomes are achieved, relief of signs and symptoms related to the nursing diagnosis will occur. The nurse caring for the patient with actual or potential malnutrition must be knowledgeable about the physiology of malnutrition and effect on breathing pattern. It is essential that the nurse assess and provide appropriate nutritional support and evaluate progress toward expected outcomes. In the event that expected outcomes are not achieved, reassessment with modification of interventions is necessary. Nurses play a key role in the total health care delivery to these complex patients. Further study will strengthen the research base of nursing interventions.

  8. Multi-layered breathing architectural envelope

    DEFF Research Database (Denmark)

    Lund Larsen, Andreas; Foged, Isak Worre; Jensen, Rasmus Lund


    A multi layered breathing envelope is developed as a method of natural ventilation. The two main layers consist of mineral wool and air permeable concrete. The mineral wool works as a dynamic insulation and the permeable concrete as a heat recovery system with a high thermal mass for heat storage...

  9. Sleep-disordered breathing in acromegaly

    Directory of Open Access Journals (Sweden)

    L K Dzeranova


    Full Text Available Sleep-disordered breathing is higly prevalent in acromegaly, disturbing patients quality of life and increasing the risk of acute cardiovascular compications. Presented clinical case discusses key considerations for timely diagnosis of sleep apnea syndrome and treatment planning. The case of 41 y.o. woman with newly diagnosed acromegaly and concomitant sleep apnea is typical for this disease.

  10. Excretory nitrogen metabolism and defence against ammonia toxicity in air-breathing fishes. (United States)

    Chew, S F; Ip, Y K


    With the development of air-breathing capabilities, some fishes can emerge from water, make excursions onto land or even burrow into mud during droughts. Air-breathing fishes have modified gill morphology and morphometry and accessory breathing organs, which would tend to reduce branchial ammonia excretion. As ammonia is toxic, air-breathing fishes, especially amphibious ones, are equipped with various strategies to ameliorate ammonia toxicity during emersion or ammonia exposure. These strategies can be categorized into (1) enhancement of ammonia excretion and reduction of ammonia entry, (2) conversion of ammonia to a less toxic product for accumulation and subsequent excretion, (3) reduction of ammonia production and avoidance of ammonia accumulation and (4) tolerance of ammonia at cellular and tissue levels. Active ammonia excretion, operating in conjunction with lowering of ambient pH and reduction in branchial and cutaneous NH₃ permeability, is theoretically the most effective strategy to maintain low internal ammonia concentrations. NH₃ volatilization involves the alkalization of certain epithelial surfaces and requires mechanisms to prevent NH₃ back flux. Urea synthesis is an energy-intensive process and hence uncommon among air-breathing teleosts. Aestivating African lungfishes detoxify ammonia to urea and the accumulated urea is excreted following arousal. Reduction in ammonia production is achieved in some air-breathing fishes through suppression of amino acid catabolism and proteolysis, or through partial amino acid catabolism leading to alanine formation. Others can slow down ammonia accumulation through increased glutamine synthesis in the liver and muscle. Yet, some others develop high tolerance of ammonia at cellular and tissue levels, including tissues in the brain. In summary, the responses of air-breathing fishes to ameliorate ammonia toxicity are many and varied, determined by the behaviour of the species and the nature of the environment in

  11. Oral Breathing Challenge in Participants with Vocal Attrition (United States)

    Sivasankar, Mahalakshmi; Fisher, Kimberly V.


    Vocal folds undergo osmotic challenge by mouth breathing during singing, exercising, and loud speaking. Just 15 min of obligatory oral breathing, to dry the vocal folds, increases phonation threshold pressure (P[subscript th]) and expiratory vocal effort in healthy speakers (M. Sivasankar & K. Fisher, 2002). We questioned whether oral breathing is…

  12. Human respiratory deposition of particles during oronasal breathing (United States)

    Swift, David L.; Proctor, Donald F.

    Deposition of particles in the tracheobronchial and pulmonary airways is computed as a function of particle size, correcting for deposition in the parallel nasal and oral airways with oronasal breathing. Thoracic deposition is lower at all sizes for oronasal breathing than for mouth breathing via tube, and is negligible for aerodynamic equivalent diameters of 10 μm or larger.

  13. 46 CFR 197.340 - Breathing gas supply. (United States)


    ... 46 Shipping 7 2010-10-01 2010-10-01 false Breathing gas supply. 197.340 Section 197.340 Shipping... GENERAL PROVISIONS Commercial Diving Operations Equipment § 197.340 Breathing gas supply. (a) A primary breathing gas supply for surface-supplied diving must be sufficient to support the following for...

  14. 46 CFR 197.312 - Breathing supply hoses. (United States)


    ... 46 Shipping 7 2010-10-01 2010-10-01 false Breathing supply hoses. 197.312 Section 197.312 Shipping... GENERAL PROVISIONS Commercial Diving Operations Equipment § 197.312 Breathing supply hoses. (a) Each breathing supply hose must— (1) Have a maximum working pressure that is equal to or exceeds— (i) The...

  15. 21 CFR 868.5330 - Breathing gas mixer. (United States)


    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Breathing gas mixer. 868.5330 Section 868.5330...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5330 Breathing gas mixer. (a) Identification. A breathing gas mixer is a device intended for use in conjunction with a respiratory...

  16. 42 CFR 84.90 - Breathing resistance test; inhalation. (United States)


    ... 42 Public Health 1 2010-10-01 2010-10-01 false Breathing resistance test; inhalation. 84.90...-Contained Breathing Apparatus § 84.90 Breathing resistance test; inhalation. (a) Resistance to inhalation airflow will be measured in the facepiece or mouthpiece while the apparatus is operated by a...

  17. 42 CFR 84.122 - Breathing resistance test; minimum requirements. (United States)


    ... 42 Public Health 1 2010-10-01 2010-10-01 false Breathing resistance test; minimum requirements. 84... Masks § 84.122 Breathing resistance test; minimum requirements. (a) Resistance to airflow will be measured in the facepiece or mouthpiece of a gas mask mounted on a breathing machine both before and...

  18. 46 CFR 197.450 - Breathing gas tests. (United States)


    ... 46 Shipping 7 2010-10-01 2010-10-01 false Breathing gas tests. 197.450 Section 197.450 Shipping....450 Breathing gas tests. The diving supervisor shall insure that— (a) The output of each air... or modification. (b) Purchased supplies of breathing mixtures supplied to a diver are checked...

  19. 21 CFR 868.5240 - Anesthesia breathing circuit. (United States)


    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Anesthesia breathing circuit. 868.5240 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5240 Anesthesia breathing circuit. (a) Identification. An anesthesia breathing circuit is a device that is intended to administer medical gases to...

  20. 42 CFR 84.115 - Breathing tubes; minimum requirements. (United States)


    ... 42 Public Health 1 2010-10-01 2010-10-01 false Breathing tubes; minimum requirements. 84.115 Section 84.115 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL... § 84.115 Breathing tubes; minimum requirements. Flexible breathing tubes used in conjunction with...

  1. 42 CFR 84.172 - Breathing tubes; minimum requirements. (United States)


    ... 42 Public Health 1 2010-10-01 2010-10-01 false Breathing tubes; minimum requirements. 84.172... Air-Purifying Particulate Respirators § 84.172 Breathing tubes; minimum requirements. Flexible breathing tubes used in conjunction with respirators shall be designed and constructed to prevent:...

  2. Control of active reflector system for radio telescope (United States)

    Zhou, Guo-hua; Li, Guo-ping; Zhang, Yong; Zhang, Zhen-chao


    According to the control requirements of the active reflector surface in the 110 m radio telescope at QiTai(QTT) Xinjiang, a new displacement actuator and a new displacement control system were designed and manufactured and then their characteristics were tested by a dual-frequency laser interferometer in the micro-displacement laboratory. The displacement actuator was designed by a scheme of high precision worm and roller screw structures, and the displacement control system was based on a ARM micro-processor. Finally, the S curve acceleration control methods were used to design the hardware platform and software algorithm for the active reflection surface of the control system. The test experiments were performed based on the laser metrology system on an active reflector close-loop antenna prototype for large radio telescope. Experimental results indicate that it achieves a 30 mm working stroke and 5 μm RMS motion resolution. The accuracy (standard deviation) is 3.67 mm, and the error between the determined and theoretical values is 0.04% when the rated load is 300 kg, the step is 2 mm and the stroke is 30mm. Furthermore, the active reflector integrated system was tested by the laser sensors with the accuracy of 0.25 μm RMS on 4-panel radio telescope prototype, the measurement results show that the integrated precision of the active reflector closed-loop control system is less than 5 μm RMS, and well satisfies the technical requirements of active reflector control system of the QTT radio telescope in 3 mm wavelength.

  3. Active control of nano dimers response using piezoelectric effect (United States)

    Mekkawy, Ahmed A.; Ali, Tamer A.; Badawi, Ashraf H.


    Nano devices can be used as building blocks for Internet of Nano-Things network devices, such as sensors/actuators, transceivers, and routers. Although nano particles response can be engineered to fit in different regimes, for such a nano particle to be used as an active nano device, its properties should be dynamically controlled. This controllability is a challenge, and there are many proposed techniques to tune nanoparticle response on the spot through a sort of control signal, wither that signal is optical (for all-optical systems) or electronic (for opto-electronic systems). This will allow the use of nano particles as nano-switches or as dynamic sensors that can pick different frequencies depending on surrounding conditions or depending on a smart decisions. In this work, we propose a piezoelectric substrate as an active control mediator to control plasmonic gaps in nano dimers. This method allows for integrating nano devices with regular electronics while communicating control signals to nano devices through applying electric signals to a piezoelectric material, in order to control the gaps between nano particles in a nano cluster. We do a full numerical study to the system, analyzing the piezoelectric control resolution (minimum gap change step) and its effect on a nanodimer response as a nanoantenna. This analysis considers the dielectric functions of materials within the visible frequencies range. The effects of different parameters, such as the piezoelectric geometrical structure and materials, on the gap control resolution and the operating frequency are studied.

  4. Smart materials and active noise and vibration control in vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Doppenberg, E.J.J.; Berkhoff, A.P.; Overbeek, M. van [TNO Institute of Applied Physics, Delft (Netherlands)


    Results are presented for the reduction of sound radiated from a structure using different control methodologies. Two approaches for active structural acoustic control are mentioned to reduce sound radiated by the structure: the acoustic approach or the vibro-acoustic approach. In both cases integrated actuators in structure materials are necessary to realise feasible products. Furthermore the development of an efficient shaker for Active Isolation techniques is described. The prototype of TNO TPD can produce a force of 400 N up to 250 Hz at a good performance-volume ratio. To enhance the robustness of the active control applications, the use of the subspace identification based control methods are developed. The robustness property of subspace identification methods forms the basis of an accurate model updating mechanism, using small size data batches. The performed simulations reveal excellent robustness performance under very general noise conditions or during operation of the control system. Furthermore the development of the techniques can be exploited to realise sound comfort requirements to enhance audible communications of vehicle related applications. To anticipate to these developments in the automotive industry, TNO has set up a Sound and Vibrations Research Centre with Twente University and a research program on Smart Panels with the Delft University. To investigate the potential markets and applications for sound comfort in the means of transportation, TNO-TPD and the Institute of Sound and Vibration Research in England (ISVR) have agreed on a cooperative venture to develop and realise 'active control of electroacoustics' (ACE). (orig.)

  5. Exercising self-control increases relative left frontal cortical activation. (United States)

    Schmeichel, Brandon J; Crowell, Adrienne; Harmon-Jones, Eddie


    Self-control refers to the capacity to override or alter a predominant response tendency. The current experiment tested the hypothesis that exercising self-control temporarily increases approach motivation, as revealed by patterns of electrical activity in the prefrontal cortex. Participants completed a writing task that did vs did not require them to exercise self-control. Then they viewed pictures known to evoke positive, negative or neutral affect. We assessed electroencephalographic (EEG) activity while participants viewed the pictures, and participants reported their trait levels of behavioral inhibition system (BIS) and behavioral activation system (BAS) sensitivity at the end of the study. We found that exercising (vs not exercising) self-control increased relative left frontal cortical activity during picture viewing, particularly among individuals with relatively higher BAS than BIS, and particularly during positive picture viewing. A similar but weaker pattern emerged during negative picture viewing. The results suggest that exercising self-control temporarily increases approach motivation, which may help to explain the aftereffects of self-control (i.e. ego depletion).

  6. Accelerometer Quantification of Physical Activity and Activity Patterns in Patients with Ankylosing Spondylitis and Population Controls

    NARCIS (Netherlands)

    van Genderen, Simon; Boonen, Annelies; van der Heijde, Desiree; Heuft, Liesbeth; Luime, Jolanda; Spoorenberg, Anneke; Arends, Suzanne; Landewe, Robert; Plasqui, Guy


    Objective. To compare the total amount of physical activity (TPA) and time spent in various activity intensities of patients with ankylosing spondylitis (AS) and population controls, and to explore factors related to physical activity (PA). Methods. Subjects were asked to wear a triaxial acceleromet

  7. Effect of slow deep breathing (6 breaths/min) on pulmonary function in healthy volunteers


    Shravya Keerthi G, Hari Krishna Bandi, Suresh M, Mallikarjuna Reddy


    We designed this study to test the hypothesis that whether 10 minutes of slow deep breathing have any effect on pulmonary function in healthy volunteers. The main objective was to study the immediate effect of slow deep breathing on Forced vital capacity (FVC), Forced expiratory volume in the first second (FEV1), Forced expiratory volume percent (FEV1/FVC%), Peak expiratory flow rate (PEFR), Forced expiratory flow 25-75%(FEF25-75%), Maximum voluntary ventilation (MVV), Slow vital capacity (SV...

  8. Switching Control of Wind Turbine Sub-Controllers Based on an Active Disturbance Rejection Technique

    Directory of Open Access Journals (Sweden)

    Yancai Xiao


    Full Text Available Wind power generation systems require complex control systems with multiple working conditions and multiple controllers. Under different operating conditions, switching without disturbancebetweenthesub-controllersplaysacriticalroleinensuringthestabilityofpowersystems. The sub-controllers of two typical cases in the permanent magnet direct drive (PMDD wind turbine running process are studied, one is the proportional integral (PI controller in the maximum power points tracking (MPPT stage, the other is the fuzzy pitch angle controller in the constant power stage. The switching strategy of the two sub-controllers is the emphasis in this research. Based on the active disturbance rejection control (ADRC, the switching mode of the sub-controllers is proposed, which can effectively restrain the sudden changes of the rotor current during the switching process, and improve the quality of power generation. The feasibility and effectiveness of the sub-controller switching strategy is verified by Matlab/Simulink simulation for a 2 MW PMDD wind turbine.

  9. Mathematical analysis of [13CO2]-expiration curves from human breath tests using [1-13C]-amino acids as oral substrate

    NARCIS (Netherlands)

    Schreurs, V.V.A.M.; Krawielitzki, K.


    A [13CO2]-breath test examines the expiration of [13CO2] as function of time after oral intake of a [13C]-labelled test substrate (single dose). In clinical settings, breath test studies are often used as a simple and non-invasive tool to diagnose the activity of metabolic functions. From a nutritio

  10. Upper limb kinematic differences between breathing and non-breathing conditions in front crawl sprint swimming. (United States)

    McCabe, Carla B; Sanders, Ross H; Psycharakis, Stelios G


    The purpose of this study was to determine whether the breathing action in front crawl (FC) sprint swimming affects the ipsilateral upper limb kinematics relative to a non-breathing stroke cycle (SC). Ten male competitive swimmers performed two 25m FC sprints: one breathing to their preferred side (Br) and one not breathing (NBr). Both swim trials were performed through a 6.75m(3) calibrated space and recorded by six gen-locked JVC KY32 CCD cameras. A paired t-test was used to assess statistical differences between the trials, with a confidence level of pswim performance is compromised by the inclusion of taking a breath in sprint FC swimming. It was proposed that swimmers aim to orient their ipsilateral shoulder into a stronger position by stretching and rolling the shoulders more in the entry phase whilst preparing to take a breath. Swimmers should focus on lengthening the push phase by extending the elbow more and not accelerating the hand too quickly upwards when preparing to inhale.

  11. Passive and Active Vibration Control of Renewable Energy Structures

    DEFF Research Database (Denmark)

    Zhang, Zili

    The present thesis deals with fundamental researches on passive and active vibration control of renewable energy structures, and provides useful models for practical applications. Effective and robust vibration control methods have been explored for mitigating the lightly damped edgewise blade...... vibration and lateral tower vibration, with the main focus on structural control devices. Rigorous theoretical modeling of different dynamic system has been established, based on which detailed design and analysis of the proposed control devices can be carried out. This thesis also explores technical...... solutions for wave energy point absorbers, in order to maximize the mean absorbed power and to deliver more smooth power to the grid. A novel suboptimal causal control law has been established for controlling the motion of the point absorber, and a new type of point absorber has also been proposed...

  12. Active Noise Control of the Heavy Truck Interior Cab

    Institute of Scientific and Technical Information of China (English)


    In order to control the noise of the heavy truck interior cab effectively, the active noise control methods are employed. First, an interior noise field test for the heavy truck is performed, and frequencies of interior noise of this vehicle are analyzed. According to the spectrum analysis of acquired noise signal, it is found out that the main frequencies of interior noise are less than 800Hz. Then the least squares lattice (LSL) algorithm is used as signal processing algorithm of the controller and a closed-loop control DSP system, based on TMS 320VC5416, is developed. The residual signal at driver's ear is used as feedback signal. Lastly, the developed ANC system is loaded into the heavy truck cab, and controlling the noise at driver's ear for that truck at different driving speeds is attempted. The noise control test results indicate that the cab interior noise is reduced averagely by 0.9 dBA at different driving speeds.

  13. Active Power Controls from Wind Power: Bridging the Gaps

    Energy Technology Data Exchange (ETDEWEB)

    Ela, E.; Gevorgian, V.; Fleming, P.; Zhang, Y. C.; Singh, M.; Muljadi, E.; Scholbrook, A.; Aho, J.; Buckspan, A.; Pao, L.; Singhvi, V.; Tuohy, A.; Pourbeik, P.; Brooks, D.; Bhatt, N.


    This paper details a comprehensive study undertaken by the National Renewable Energy Laboratory, Electric Power Research Institute, and the University of Colorado to understand how the contribution of wind power providing active power control (APC) can benefit the total power system economics, increase revenue streams, improve the reliability and security of the power system, and provide superior and efficient response while reducing any structural and loading impacts that may reduce the life of the wind turbine or its components. The study includes power system simulations, control simulations, and actual field tests using turbines at NREL's National Wind Technology Center (NWTC). The study focuses on synthetic inertial control, primary frequency control, and automatic generation control, and analyzes timeframes ranging from milliseconds to minutes to the lifetime of wind turbines, locational scope ranging from components of turbines to large wind plants to entire synchronous interconnections, and additional topics ranging from economics to power system engineering to control design.

  14. Dual Control with Active Learning using Gaussian Process Regression

    CERN Document Server

    Alpcan, Tansu


    In many real world problems, control decisions have to be made with limited information. The controller may have no a priori (or even posteriori) data on the nonlinear system, except from a limited number of points that are obtained over time. This is either due to high cost of observation or the highly non-stationary nature of the system. The resulting conflict between information collection (identification, exploration) and control (optimization, exploitation) necessitates an active learning approach for iteratively selecting the control actions which concurrently provide the data points for system identification. This paper presents a dual control approach where the information acquired at each control step is quantified using the entropy measure from information theory and serves as the training input to a state-of-the-art Gaussian process regression (Bayesian learning) method. The explicit quantification of the information obtained from each data point allows for iterative optimization of both identifica...

  15. Control System Design of Shunt Active Power Filter Based on Active Disturbance Rejection and Repetitive Control Techniques

    Directory of Open Access Journals (Sweden)

    Le Ge


    Full Text Available To rely on joint active disturbance rejection control (ADRC and repetitive control (RC, in this paper, a compound control law for active power filter (APF current control system is proposed. According to the theory of ADRC, the uncertainties in the model and from the circumstance outside are considered as the unknown disturbance to the system. The extended state observer can evaluate the unknown disturbance. Next, RC is introduced into current loop to improve the steady characteristics. The ADRC is used to get a good dynamic performance, and RC is used to get a good static performance. A good simulation result is got through choosing and changing the parameters, and the feasibility, adaptability, and robustness of the control are testified by this result.

  16. The Control of Transmitted Power in an Active Isolation System

    DEFF Research Database (Denmark)

    Elliott, S.J.; Gardonio, P.; Pinnington, R.J.


    and distributed active mounts, and these models can be connected together to produce an overall theoretical description of a realistic active isolation system. Total transmitted power has been found to be an excellent criterion to quantify the effect of various control strategies in this model in which...... the contributions to the transmitted power in the various degrees of freedom can be clearly understood. It has also been found, however, that an active control system which minimises a practical estimate of transmitted power, calculated from the product of the axial forces and velocities under the mounts, can give...... a very poor performance in terms of reducing the total transmitted power, and can even increase it under some circumstances. Such a control system was also found to be very sensitive to measurement errors and the presence of flanking paths, which give rise to the phenomena of 'power circulation'. A more...

  17. Online identification of active absorbers in automotive vibration control

    Energy Technology Data Exchange (ETDEWEB)

    Buttelmann, M.; Lohmann, B.; Vinogradski, M.; Nedeljkovic, N. [Bremen Univ. (Germany). Inst. fuer Automatisierungstechnik; Marienfeld, P. [ContiTech Vibration Control GmbH, Hannover (Germany); Svaricek, F. [Continental Gummi-Werke AG, Hannover (Germany)


    In the past, engine-related noise and vibration in the vehicle cabin was exclusively reduced by passive absorption. Today, modern actuators and control systems make an active noise reduction possible by introducing counteracting vibration at 180 degrees phase lag. Within a cooperation of the Institute of Automation Systems and Continental AG, an approach using active absorbers at the engine mounts is investigated. As the dynamic behaviour of the active absorbers and other elements in the secondary path are time-variant (depending on temperature, age and other factors), an online identification is carried out. By this, the implemented feedforward control strategy is supported on a precise and frequently updated model of the secondary path. The chosen approaches to online and offline identification are presented together with first results achieved in online identification and with the overall control system. (orig.)

  18. Machine modification for active MHD control in RFX

    Energy Technology Data Exchange (ETDEWEB)

    Sonato, P. E-mail:; Chitarin, G.; Zaccaria, P.; Gnesotto, F.; Ortolani, S.; Buffa, A.; Bagatin, M.; Baker, W.R.; Dal Bello, S.; Fiorentin, P.; Grando, L.; Marchiori, G.; Marcuzzi, D.; Masiello, A.; Peruzzo, S.; Pomaro, N.; Serianni, G


    Recent studies on RFP and Tokamak devices call for an active control of the MHD and resistive wall modes to induce plasma mode rotation and to prevent mode phase locking. The results obtained on RFX, where slow rotation of phase locked modes has been induced, support the possibility of extending active MHD mode control through a substantial modification of the device. A new first wall with an integrated system of electric and magnetic transducers has been realised. A close fitting 3 mm thick Cu shell replaces the 65 mm Al shell. A toroidal support structure (TSS) made of stainless steel replaces the shell in supporting all the forces acting on the torus. A system of 192 saddle coils is provided to actively control the MHD modes. This system completely surrounds the toroidal surface and allows the generation of harmonic fields with m=0 and m=1 poloidal wave number and with a toroidal spectrum up to n=24.

  19. Activities of the control services. First quarter 1997; Activites des services du controle. Premier trimestre 1997

    Energy Technology Data Exchange (ETDEWEB)



    This paper summarizes the control activities of the technical service of electric power and big dams: annual examinations, administrative instructions (draining, floods, granting renewal), decennial examinations etc. (J.S.)

  20. Strain-optic active control for quantum integrated photonics

    CERN Document Server

    Humphreys, Peter C; Spring, Justin B; Moore, Merritt; Salter, Patrick S; Booth, Martin J; Kolthammer, W Steven; Walmsley, Ian A


    We present a practical method for active phase control on a photonic chip that has immediate applications in quantum photonics. Our approach uses strain-optic modification of the refractive index of individual waveguides, effected by a millimeter-scale mechanical actuator. The resulting phase change of propagating optical fields is rapid and polarization-dependent, enabling quantum applications that require active control and polarization encoding. We demonstrate strain-optic control of non-classical states of light in silica, showing the generation of 2-photon polarisation N00N states by manipulating Hong-Ou-Mandel interference. We also demonstrate switching times of a few microseconds, which are sufficient for silica-based feed-forward control of photonic quantum states.

  1. 3rd Active Flow and Combustion Control Conference

    CERN Document Server


    The book reports on the latest theoretical and experimental advances in the  field of active flow and combustion control. It covers new developments in actuator technology and sensing, in robust and optimal open- and closed-loop control, as well as in model reduction for control. It collects contributions presented during the third edition of the Active Flow and Combustion Control conference, held in September 10-12, 2014 at the Technische Universität Berlin (Germany). This conference, as well as the research presented in the book, have been supported by the collaborative research center SFB 1029 -Substantial efficiency increase in gas turbines through direct use of coupled unsteady combustion and flow dynamics, funded by the DFG (German Research Foundation).

  2. Clinical Efficacy of Piracetam on Breath Holding Spells in Children

    Directory of Open Access Journals (Sweden)

    F. Ashrafzadeh


    Full Text Available Breath holding spells (BHS is a type of syncope in children , most commonly encontered in the early years of life. Although these athacks don't damage the brain , if these are frequent or prolonged cause , parents frighten , so physician should intervent. In this study we evaluated clinical efficacy of piracetam on B.H.S of children in Mashhad Ghaem Hospital during 2001-2002.In this double blind placebo control study , piracetam or placebo on a randomized basis was administered to children with 40 mg/kg/day in 2 divided doses for 2 months. From the 41 children that were enrolled , 21 cases received piracetam and 20 cases received placebo. Parents denoted the numbers of spells two months before and two months after taking drug. Control of breath holding spells were observed in 90.5% of patients in the group taking piracetam as compared with 40% in the group taking placebo (P = 0.002. Of the all patients 10 cases had iron deficiency anemia so they had taken elemental Fe too. The side effects were the same in these two groups. The results of this study indicated that piracetam was efficient for the treatment of children with B.H.S without greater incidence adverse effects than placebo.

  3. Active Flow Control of Lifting Surface With Flap-Current Activities and Future Directions (United States)

    Ahmadi, G.; Marzocca, P.; Jha, R.; Alstorm, B.; Obied, S.; Kabir, P.; Shahrabi, A.


    The main objective is to develop effective control strategies for separation control of an airfoil with a single hinge flap. The specific objectives are: Develop an active control architecture for flow control around an airfoil with flap. Design, fabricate, a wind tunnel test of a high lift wing (with flap) with integrated actuators and sensors. Design, development and fabrication of synthetic jet actuators. Develop appropriate control strategy for application to the airfoil. Wind tunnel testing of the high lift wing at various angles of attack and flap positions with closed loop control.

  4. Masticatory Changes in Oral Breath Secondary to Allergic Rhinitis: Integrative Review

    Directory of Open Access Journals (Sweden)

    Bezerra, Luciana Ângelo


    Full Text Available Introduction The III Brazilian Consensus on Rhinitis (2012 defines allergic rhinitis as a nasal mucosa inflammation, mediated by immunoglobulin E, after exposure to allergens. The classic signs and symptoms of allergic rhinitis are nasal obstruction, watery rhinorrhea, sneezing, and nasal itching, often reversible either spontaneously or with treatment, and mouth breathing (breathing predominantly through the mouth, regardless of the cause, due to a nasal breathing impairment in some cases. Objective To evaluate the literature on masticatory changes in children with mouth breathing due to allergic rhinitis. Methods We conducted a search of the past 10 years, at Bireme and MEDLINE databases, for articles that covered masticatory changes in children with mouth breathing secondary to allergic rhinitis. Results We found 1,986 articles, including 15 repeated in databases, but only two articles met the inclusion criteria fully. Discussion We found few studies to answer the question raised in this review, and those studies have some methodological limitations. Most articles claimed no have statistically significant differences in masticatory changes in this population. Conclusion A better controlled study (isolating diseases, exposure time, with a larger sample (sample calculation appropriate, would be necessary to examine such changes.

  5. Enhancing sensorimotor activity by controlling virtual objects with gaze.

    Directory of Open Access Journals (Sweden)

    Cristián Modroño

    Full Text Available This fMRI work studies brain activity of healthy volunteers who manipulated a virtual object in the context of a digital game by applying two different control methods: using their right hand or using their gaze. The results show extended activations in sensorimotor areas, not only when participants played in the traditional way (using their hand but also when they used their gaze to control the virtual object. Furthermore, with the exception of the primary motor cortex, regional motor activity was similar regardless of what the effector was: the arm or the eye. These results have a potential application in the field of the neurorehabilitation as a new approach to generate activation of the sensorimotor system to support the recovery of the motor functions.

  6. Vibration control of flexible beams using an active hinge (United States)

    Cudney, H. H., Jr.; Inman, D. J.; Horner, G. C.


    The use of an active hinge to attenuate the transverse vibrations of a flexible beam is examined. A slender aluminum beam is suspended vertically, cantilevered at the top. An active hinge is placed at the node of the second vibration mode. The active hinge consists of a torque motor, strain gauge, and tachometer. A control law is implemented using both beam-bending strain and the relative angular velocity measured at this hinge, thereby configuring the hinge to act as an active damper. Results from implementing this control law show little improvement in the first mode damping ratio, 130 percent increase in the second mode damping ratio, and 180 percent increase in the third mode damping ratio. The merits of using a motor with a gearbox are discussed.

  7. A Review of Virtual Sensing Algorithms for Active Noise Control

    Directory of Open Access Journals (Sweden)

    Danielle Moreau


    Full Text Available Traditional local active noise control systems minimise the measured acoustic pressure to generate a zone of quiet at the physical error sensor location. The resulting zone of quiet is generally limited in size and this requires the physical error sensor be placed at the desired location of attenuation, which is often inconvenient. To overcome this, a number of virtual sensing algorithms have been developed for active noise control. Using the physical error signal, the control signal and knowledge of the system, these virtual sensing algorithms estimate the error signal at a location that is remote from the physical error sensor, referred to as the virtual location. Instead of minimising the physical error signal, the estimated error signal is minimised with the active noise control system to generate a zone of quiet at the virtual location. This paper will review a number of virtual sensing algorithms developed for active noise control. Additionally, the performance of these virtual sensing algorithms in numerical simulations and in experiments is discussed and compared.

  8. Goal-congruent default network activity facilitates cognitive control. (United States)

    Spreng, R Nathan; DuPre, Elizabeth; Selarka, Dhawal; Garcia, Juliana; Gojkovic, Stefan; Mildner, Judith; Luh, Wen-Ming; Turner, Gary R


    Substantial neuroimaging evidence suggests that spontaneous engagement of the default network impairs performance on tasks requiring executive control. We investigated whether this impairment depends on the congruence between executive control demands and internal mentation. We hypothesized that activation of the default network might enhance performance on an executive control task if control processes engage long-term memory representations that are supported by the default network. Using fMRI, we scanned 36 healthy young adult humans on a novel two-back task requiring working memory for famous and anonymous faces. In this task, participants (1) matched anonymous faces interleaved with anonymous face, (2) matched anonymous faces interleaved with a famous face, or (3) matched a famous faces interleaved with an anonymous face. As predicted, we observed a facilitation effect when matching famous faces, compared with anonymous faces. We also observed greater activation of the default network during these famous face-matching trials. The results suggest that activation of the default network can contribute to task performance during an externally directed executive control task. Our findings provide evidence that successful activation of the default network in a contextually relevant manner facilitates goal-directed cognition.

  9. Active Molecular Plasmonics: Controlling Plasmon Resonances with Molecular Switches

    KAUST Repository

    Zheng, Yue Bing


    A gold nanodisk array, coated with bistable, redox-controllable [2]rotaxane molecules, when exposed to chemical oxidants and reductants, undergoes switching of its plasmonic properties reversibly. By contrast, (i) bare gold nanodisks and (ii) disks coated with a redox-active, but mechanically inert, control compound do not display surface-plasmon-based switching. Along with calculations based on time-dependent density functional theory, these experimental observations suggest that the nanoscale movements within surface-bound “molecular machines” can be used as the active components in plasmonic devices.


    Institute of Scientific and Technical Information of China (English)

    Song Kongjie; Zhang Bing; Sun Lingling; Sun Yuguo


    Passive-active control of a flexible isolation system is investigated from the viewpoint of power flow. Dynamic transfer equations of the system are deduced based on a matrix method which uses mobility or impedance representations of three substructures: the source of vibration, the receiver and the mounting system which connects the source to the receiver. The cancellation of axial input forces to the receiver is considered as the active control strategy and its effects are discussed. The results of the study show that the strategy adopted herein can effectively reduce the power transmitted to the receiver.

  11. Interaction between functional health literacy, patient activation, and glycemic control

    Directory of Open Access Journals (Sweden)

    Woodard LD


    Full Text Available LeChauncy D Woodard, Cassie R Landrum, Amber B Amspoker, David Ramsey, Aanand D Naik Veterans Affairs Health Services Research and Development Center for Innovations in Quality, Effectiveness and Safety, Michael E DeBakey Veterans Affairs Medical Center, and Section of Health Services Research, Department of Medicine, Baylor College of Medicine, Houston, TX, USA Background: Functional health literacy (FHL and patient activation can impact diabetes control through enhanced diabetes self-management. Less is known about the combined effect of these characteristics on diabetes outcomes. Using brief, validated measures, we examined the interaction between FHL and patient activation in predicting glycosylated hemoglobin (HbA1c control among a cohort of multimorbid diabetic patients.Methods: We administered a survey via mail to 387 diabetic patients with coexisting ­hypertension and ischemic heart disease who received outpatient care at one regional VA medical center between November 2010 and December 2010. We identified patients with the study conditions using the International Classification of Diseases-Ninth Revision-Clinical ­Modification (ICD-9-CM diagnoses codes and Current Procedure Terminology (CPT ­procedures codes. Surveys were returned by 195 (50.4% patients. We determined patient activation levels based on participant responses to the 13-item Patient Activation Measure and FHL levels using the single-item screening question, “How confident are you filling out medical forms by yourself?” We reviewed patient medical records to assess glycemic control. We used multiple logistic regression to examine whether activation and FHL were individually or jointly related to HbA1c control.Results: Neither patient activation nor FHL was independently related to glycemic control in the unadjusted main effects model; however, the interaction between the two was significantly associated with glycemic control (odds ratio 1.05 [95% confidence

  12. Control of chaotic oscillators via a class of model free active controller: Suppresion and synchronization

    Energy Technology Data Exchange (ETDEWEB)

    Aguilar-Lopez, Ricardo [Division de Ciencias Basicas e Ingenieria, Universidad Autonoma Metropolitana, Av. San Pablo No. 180, Reynosa-Tamaulipas, 02200, Azcapotzalco, Mexico D.F. (Mexico)], E-mail:; Martinez-Guerra, Rafael [Departamento de Control Automatico, CINVESTAV-IPN, Apartado Postal 14-740, 07360 Mexico D.F. (Mexico)], E-mail:


    The goal of this work is related with the control of chaotic oscillators for chaos suppression and synchronization purposes. The proposed methodology is related with a class of robust active control (RAC) law, where the stabilizing part of the control structure is related with an integral high order sliding-mode and proportional form of the so-called control error. The proposed controller is applied to chaos suppression, synchronization and anti-synchronization tasks for nonlinear oscillators with different order and structure. Numerical experiments illustrate the satisfactory performance of the proposed methodology, when it is applied to Duffing and Chen oscillators.

  13. A Device for Respiratory Monitoring during Nutritive Sucking: Response to Neonatal Breathing Patterns

    Directory of Open Access Journals (Sweden)

    Andrea Rosi


    Full Text Available The quantitative monitoring of breathing, sucking, and swallowing is required to predict newborns’ neurodevelopmental outcomes. In particular, the coordination of breathing timing with respect to sucking cycle is crucial. In this work, we present the characterization of a low-cost flowmeter designed for noninvasive recording of breathing pattern during bottle feeding. The transducer is designed to be integrated on a commercial feeding bottle also instrumented with a system for sucking monitoring. The flowmeter consists of two transistors (hot bodies supplied at constant current, which are placed in a duct used to convey the inspiratory and expiratory flow coming from the newborn’s nostrils. The transducer design, its static calibration, and its response time are discussed. Moreover, a custom-made active lung simulator was used to perform a feasibility assessment of the proposed flowmeter for respiratory monitoring of neonatal respiratory patterns. The flowmeter has a discrimination threshold <0.5 L·min−1 and a response time of 347±12 ms. The breathing period estimated by the proposed transducer was compared with the one measured by a high performance flowmeter, used as reference: the mean absolute error was <11%. Results highlighted the ability of the device to track respiratory patterns at frequencies typical of neonatal breathing.

  14. A Quarter Active Suspension System Based Ground-Hook Controller


    Turnip Arjon


    An alternative design technique for active suspension system of vehicle using a developved ground-hook damping system as a reference is proposed. The controller parameters are determined using Lyapunov method and can be tuned to precisely achieve the type of desired response which given by reference model. The simulation result show that the designed active suspension system based ground-hook reference model is able to significantly improve the ride comfort and the road holding compared with ...

  15. Human ECG signal parameters estimation during controlled physical activity (United States)

    Maciejewski, Marcin; Surtel, Wojciech; Dzida, Grzegorz


    ECG signal parameters are commonly used indicators of human health condition. In most cases the patient should remain stationary during the examination to decrease the influence of muscle artifacts. During physical activity, the noise level increases significantly. The ECG signals were acquired during controlled physical activity on a stationary bicycle and during rest. Afterwards, the signals were processed using a method based on Pan-Tompkins algorithms to estimate their parameters and to test the method.

  16. Active disturbance rejection control for hydraulic width control system for rough mill

    Institute of Scientific and Technical Information of China (English)


    The highly nonlinear behavior of the system limits the performance of classical linear proportional and integral (PI) controllers used for hot rolling. An active disturbance rejection controller is proposed in this paper to deal with the nonlinear problem of hydraulic servo system in order to preserve fast response and small overshoot of control system. The active disturbance rejection (ADR) controller is composed of nonlinear tracking differentiator (TD), extended state observer (ESO) and nonlinear feedback (NF) law. An example of the hydraulic edger system case study is investigated to show the effectiveness and robustness of the proposed nonlinear controller, especially, in the circumstance of foreign disturbance and working condition variation,compared with classic PI controller.

  17. Satellite Dynamic Damping via Active Force Control Augmentation (United States)

    Varatharajoo, Renuganth


    An approach that incorporates the Active Force Control (AFC) technique into a conventional Proportional-Derivative (PD) controller is proposed for a satellite active dynamic damping towards a full attitude control. The AFC method has been established to facilitate a robust motion control of dynamical systems in the presence of disturbances, parametric uncertainties and changes that are commonly prevalent in the real-world environment. The usefulness of the method can be extended by introducing intelligent mechanisms to approximate the mass or inertia matrix of the dynamic system to trigger the compensation effect of the controller. AFC is a technique that relies on the appropriate estimation of the inertial or mass parameters of the dynamic system and the measurements of the acceleration and force signals induced by the system if practical implementation is ever considered. In AFC, it is shown that the system subjected to a number of disturbances remains stable and robust via the compensating action of the control strategy. We demonstrate that it is possible to design a spacecraft attitude feedback controller that will ensure the system dynamics set point remains unchanged even in the presence of the disturbances provided that the actual disturbances can be modeled effectively. In order to further facilitate this analysis, a combined energy and attitude control system (CEACS) is proposed as a model satellite attitude control actuator. All the governing equations are established and the proposed satellite attitude control architecture is made amenable to numerical treatments. The results show that the PD-AFC attitude damping performances are superiorly better than that of the solely PD type. It is also shown that the tunings of the AFC system gains are crucial to ensure a better attitude damping performance and this process is mandatory for AFC systems. Finally, the results demonstrate an important satellite dynamic damping enhancement capability using the AFC

  18. A new robust adaptive controller for vibration control of active engine mount subjected to large uncertainties (United States)

    Fakhari, Vahid; Choi, Seung-Bok; Cho, Chang-Hyun


    This work presents a new robust model reference adaptive control (MRAC) for vibration control caused from vehicle engine using an electromagnetic type of active engine mount. Vibration isolation performances of the active mount associated with the robust controller are evaluated in the presence of large uncertainties. As a first step, an active mount with linear solenoid actuator is prepared and its dynamic model is identified via experimental test. Subsequently, a new robust MRAC based on the gradient method with σ-modification is designed by selecting a proper reference model. In designing the robust adaptive control, structured (parametric) uncertainties in the stiffness of the passive part of the mount and in damping ratio of the active part of the mount are considered to investigate the robustness of the proposed controller. Experimental and simulation results are presented to evaluate performance focusing on the robustness behavior of the controller in the face of large uncertainties. The obtained results show that the proposed controller can sufficiently provide the robust vibration control performance even in the presence of large uncertainties showing an effective vibration isolation.

  19. 谈舞蹈训练中的呼吸%Discussion on Breath in Dance Training

    Institute of Scientific and Technical Information of China (English)



    Breath plays a pivotal role in dance training and per-formance, as it endows dance with artistic vitality. In addition, the performance of dance works not only relies on merely dance movements, but also on breath to help complete body control. This paper specifically explores the importance and utilization techniques of breath in dance training.%呼吸在舞蹈训练及表演中起着非常重要的作用,呼吸给予舞蹈以艺术生命力;同时,舞蹈作品的表现不仅仅只依靠舞蹈动作来完成,其更需要呼吸来完成身体的控制。本文将主要对呼吸在舞蹈训练中的重要性及运用技巧进行具体的探讨。

  20. Quarter Car Active Suspension System Control Using PID Controller tuned by PSO


    Wissam H. Al-Mutar


    The objective of this paper is to design an efficient control scheme for car suspension system. The purpose of suspension system in vehicles is to get more comfortable riding and good handling with road vibrations. A nonlinear hydraulic actuator is connected to passive suspension system in parallel with damper. The Particles Swarm Optimization is used to tune a PID controller for active suspension system. The designed controller is applied for quarter car suspension system and result is compa...